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Commit | Line | Data |
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ac27a0ec | 1 | /* |
617ba13b | 2 | * linux/fs/ext4/inode.c |
ac27a0ec DK |
3 | * |
4 | * Copyright (C) 1992, 1993, 1994, 1995 | |
5 | * Remy Card (card@masi.ibp.fr) | |
6 | * Laboratoire MASI - Institut Blaise Pascal | |
7 | * Universite Pierre et Marie Curie (Paris VI) | |
8 | * | |
9 | * from | |
10 | * | |
11 | * linux/fs/minix/inode.c | |
12 | * | |
13 | * Copyright (C) 1991, 1992 Linus Torvalds | |
14 | * | |
15 | * Goal-directed block allocation by Stephen Tweedie | |
16 | * (sct@redhat.com), 1993, 1998 | |
17 | * Big-endian to little-endian byte-swapping/bitmaps by | |
18 | * David S. Miller (davem@caip.rutgers.edu), 1995 | |
19 | * 64-bit file support on 64-bit platforms by Jakub Jelinek | |
20 | * (jj@sunsite.ms.mff.cuni.cz) | |
21 | * | |
617ba13b | 22 | * Assorted race fixes, rewrite of ext4_get_block() by Al Viro, 2000 |
ac27a0ec DK |
23 | */ |
24 | ||
25 | #include <linux/module.h> | |
26 | #include <linux/fs.h> | |
27 | #include <linux/time.h> | |
dab291af | 28 | #include <linux/jbd2.h> |
ac27a0ec DK |
29 | #include <linux/highuid.h> |
30 | #include <linux/pagemap.h> | |
31 | #include <linux/quotaops.h> | |
32 | #include <linux/string.h> | |
33 | #include <linux/buffer_head.h> | |
34 | #include <linux/writeback.h> | |
64769240 | 35 | #include <linux/pagevec.h> |
ac27a0ec | 36 | #include <linux/mpage.h> |
e83c1397 | 37 | #include <linux/namei.h> |
ac27a0ec DK |
38 | #include <linux/uio.h> |
39 | #include <linux/bio.h> | |
4c0425ff | 40 | #include <linux/workqueue.h> |
9bffad1e | 41 | |
3dcf5451 | 42 | #include "ext4_jbd2.h" |
ac27a0ec DK |
43 | #include "xattr.h" |
44 | #include "acl.h" | |
d2a17637 | 45 | #include "ext4_extents.h" |
ac27a0ec | 46 | |
9bffad1e TT |
47 | #include <trace/events/ext4.h> |
48 | ||
a1d6cc56 AK |
49 | #define MPAGE_DA_EXTENT_TAIL 0x01 |
50 | ||
678aaf48 JK |
51 | static inline int ext4_begin_ordered_truncate(struct inode *inode, |
52 | loff_t new_size) | |
53 | { | |
7f5aa215 JK |
54 | return jbd2_journal_begin_ordered_truncate( |
55 | EXT4_SB(inode->i_sb)->s_journal, | |
56 | &EXT4_I(inode)->jinode, | |
57 | new_size); | |
678aaf48 JK |
58 | } |
59 | ||
64769240 AT |
60 | static void ext4_invalidatepage(struct page *page, unsigned long offset); |
61 | ||
ac27a0ec DK |
62 | /* |
63 | * Test whether an inode is a fast symlink. | |
64 | */ | |
617ba13b | 65 | static int ext4_inode_is_fast_symlink(struct inode *inode) |
ac27a0ec | 66 | { |
617ba13b | 67 | int ea_blocks = EXT4_I(inode)->i_file_acl ? |
ac27a0ec DK |
68 | (inode->i_sb->s_blocksize >> 9) : 0; |
69 | ||
70 | return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0); | |
71 | } | |
72 | ||
ac27a0ec DK |
73 | /* |
74 | * Work out how many blocks we need to proceed with the next chunk of a | |
75 | * truncate transaction. | |
76 | */ | |
77 | static unsigned long blocks_for_truncate(struct inode *inode) | |
78 | { | |
725d26d3 | 79 | ext4_lblk_t needed; |
ac27a0ec DK |
80 | |
81 | needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9); | |
82 | ||
83 | /* Give ourselves just enough room to cope with inodes in which | |
84 | * i_blocks is corrupt: we've seen disk corruptions in the past | |
85 | * which resulted in random data in an inode which looked enough | |
617ba13b | 86 | * like a regular file for ext4 to try to delete it. Things |
ac27a0ec DK |
87 | * will go a bit crazy if that happens, but at least we should |
88 | * try not to panic the whole kernel. */ | |
89 | if (needed < 2) | |
90 | needed = 2; | |
91 | ||
92 | /* But we need to bound the transaction so we don't overflow the | |
93 | * journal. */ | |
617ba13b MC |
94 | if (needed > EXT4_MAX_TRANS_DATA) |
95 | needed = EXT4_MAX_TRANS_DATA; | |
ac27a0ec | 96 | |
617ba13b | 97 | return EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + needed; |
ac27a0ec DK |
98 | } |
99 | ||
100 | /* | |
101 | * Truncate transactions can be complex and absolutely huge. So we need to | |
102 | * be able to restart the transaction at a conventient checkpoint to make | |
103 | * sure we don't overflow the journal. | |
104 | * | |
105 | * start_transaction gets us a new handle for a truncate transaction, | |
106 | * and extend_transaction tries to extend the existing one a bit. If | |
107 | * extend fails, we need to propagate the failure up and restart the | |
108 | * transaction in the top-level truncate loop. --sct | |
109 | */ | |
110 | static handle_t *start_transaction(struct inode *inode) | |
111 | { | |
112 | handle_t *result; | |
113 | ||
617ba13b | 114 | result = ext4_journal_start(inode, blocks_for_truncate(inode)); |
ac27a0ec DK |
115 | if (!IS_ERR(result)) |
116 | return result; | |
117 | ||
617ba13b | 118 | ext4_std_error(inode->i_sb, PTR_ERR(result)); |
ac27a0ec DK |
119 | return result; |
120 | } | |
121 | ||
122 | /* | |
123 | * Try to extend this transaction for the purposes of truncation. | |
124 | * | |
125 | * Returns 0 if we managed to create more room. If we can't create more | |
126 | * room, and the transaction must be restarted we return 1. | |
127 | */ | |
128 | static int try_to_extend_transaction(handle_t *handle, struct inode *inode) | |
129 | { | |
0390131b FM |
130 | if (!ext4_handle_valid(handle)) |
131 | return 0; | |
132 | if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1)) | |
ac27a0ec | 133 | return 0; |
617ba13b | 134 | if (!ext4_journal_extend(handle, blocks_for_truncate(inode))) |
ac27a0ec DK |
135 | return 0; |
136 | return 1; | |
137 | } | |
138 | ||
139 | /* | |
140 | * Restart the transaction associated with *handle. This does a commit, | |
141 | * so before we call here everything must be consistently dirtied against | |
142 | * this transaction. | |
143 | */ | |
fa5d1113 | 144 | int ext4_truncate_restart_trans(handle_t *handle, struct inode *inode, |
487caeef | 145 | int nblocks) |
ac27a0ec | 146 | { |
487caeef JK |
147 | int ret; |
148 | ||
149 | /* | |
150 | * Drop i_data_sem to avoid deadlock with ext4_get_blocks At this | |
151 | * moment, get_block can be called only for blocks inside i_size since | |
152 | * page cache has been already dropped and writes are blocked by | |
153 | * i_mutex. So we can safely drop the i_data_sem here. | |
154 | */ | |
0390131b | 155 | BUG_ON(EXT4_JOURNAL(inode) == NULL); |
ac27a0ec | 156 | jbd_debug(2, "restarting handle %p\n", handle); |
487caeef JK |
157 | up_write(&EXT4_I(inode)->i_data_sem); |
158 | ret = ext4_journal_restart(handle, blocks_for_truncate(inode)); | |
159 | down_write(&EXT4_I(inode)->i_data_sem); | |
fa5d1113 | 160 | ext4_discard_preallocations(inode); |
487caeef JK |
161 | |
162 | return ret; | |
ac27a0ec DK |
163 | } |
164 | ||
165 | /* | |
166 | * Called at the last iput() if i_nlink is zero. | |
167 | */ | |
af5bc92d | 168 | void ext4_delete_inode(struct inode *inode) |
ac27a0ec DK |
169 | { |
170 | handle_t *handle; | |
bc965ab3 | 171 | int err; |
ac27a0ec | 172 | |
678aaf48 JK |
173 | if (ext4_should_order_data(inode)) |
174 | ext4_begin_ordered_truncate(inode, 0); | |
ac27a0ec DK |
175 | truncate_inode_pages(&inode->i_data, 0); |
176 | ||
177 | if (is_bad_inode(inode)) | |
178 | goto no_delete; | |
179 | ||
bc965ab3 | 180 | handle = ext4_journal_start(inode, blocks_for_truncate(inode)+3); |
ac27a0ec | 181 | if (IS_ERR(handle)) { |
bc965ab3 | 182 | ext4_std_error(inode->i_sb, PTR_ERR(handle)); |
ac27a0ec DK |
183 | /* |
184 | * If we're going to skip the normal cleanup, we still need to | |
185 | * make sure that the in-core orphan linked list is properly | |
186 | * cleaned up. | |
187 | */ | |
617ba13b | 188 | ext4_orphan_del(NULL, inode); |
ac27a0ec DK |
189 | goto no_delete; |
190 | } | |
191 | ||
192 | if (IS_SYNC(inode)) | |
0390131b | 193 | ext4_handle_sync(handle); |
ac27a0ec | 194 | inode->i_size = 0; |
bc965ab3 TT |
195 | err = ext4_mark_inode_dirty(handle, inode); |
196 | if (err) { | |
197 | ext4_warning(inode->i_sb, __func__, | |
198 | "couldn't mark inode dirty (err %d)", err); | |
199 | goto stop_handle; | |
200 | } | |
ac27a0ec | 201 | if (inode->i_blocks) |
617ba13b | 202 | ext4_truncate(inode); |
bc965ab3 TT |
203 | |
204 | /* | |
205 | * ext4_ext_truncate() doesn't reserve any slop when it | |
206 | * restarts journal transactions; therefore there may not be | |
207 | * enough credits left in the handle to remove the inode from | |
208 | * the orphan list and set the dtime field. | |
209 | */ | |
0390131b | 210 | if (!ext4_handle_has_enough_credits(handle, 3)) { |
bc965ab3 TT |
211 | err = ext4_journal_extend(handle, 3); |
212 | if (err > 0) | |
213 | err = ext4_journal_restart(handle, 3); | |
214 | if (err != 0) { | |
215 | ext4_warning(inode->i_sb, __func__, | |
216 | "couldn't extend journal (err %d)", err); | |
217 | stop_handle: | |
218 | ext4_journal_stop(handle); | |
219 | goto no_delete; | |
220 | } | |
221 | } | |
222 | ||
ac27a0ec | 223 | /* |
617ba13b | 224 | * Kill off the orphan record which ext4_truncate created. |
ac27a0ec | 225 | * AKPM: I think this can be inside the above `if'. |
617ba13b | 226 | * Note that ext4_orphan_del() has to be able to cope with the |
ac27a0ec | 227 | * deletion of a non-existent orphan - this is because we don't |
617ba13b | 228 | * know if ext4_truncate() actually created an orphan record. |
ac27a0ec DK |
229 | * (Well, we could do this if we need to, but heck - it works) |
230 | */ | |
617ba13b MC |
231 | ext4_orphan_del(handle, inode); |
232 | EXT4_I(inode)->i_dtime = get_seconds(); | |
ac27a0ec DK |
233 | |
234 | /* | |
235 | * One subtle ordering requirement: if anything has gone wrong | |
236 | * (transaction abort, IO errors, whatever), then we can still | |
237 | * do these next steps (the fs will already have been marked as | |
238 | * having errors), but we can't free the inode if the mark_dirty | |
239 | * fails. | |
240 | */ | |
617ba13b | 241 | if (ext4_mark_inode_dirty(handle, inode)) |
ac27a0ec DK |
242 | /* If that failed, just do the required in-core inode clear. */ |
243 | clear_inode(inode); | |
244 | else | |
617ba13b MC |
245 | ext4_free_inode(handle, inode); |
246 | ext4_journal_stop(handle); | |
ac27a0ec DK |
247 | return; |
248 | no_delete: | |
249 | clear_inode(inode); /* We must guarantee clearing of inode... */ | |
250 | } | |
251 | ||
252 | typedef struct { | |
253 | __le32 *p; | |
254 | __le32 key; | |
255 | struct buffer_head *bh; | |
256 | } Indirect; | |
257 | ||
258 | static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v) | |
259 | { | |
260 | p->key = *(p->p = v); | |
261 | p->bh = bh; | |
262 | } | |
263 | ||
ac27a0ec | 264 | /** |
617ba13b | 265 | * ext4_block_to_path - parse the block number into array of offsets |
ac27a0ec DK |
266 | * @inode: inode in question (we are only interested in its superblock) |
267 | * @i_block: block number to be parsed | |
268 | * @offsets: array to store the offsets in | |
8c55e204 DK |
269 | * @boundary: set this non-zero if the referred-to block is likely to be |
270 | * followed (on disk) by an indirect block. | |
ac27a0ec | 271 | * |
617ba13b | 272 | * To store the locations of file's data ext4 uses a data structure common |
ac27a0ec DK |
273 | * for UNIX filesystems - tree of pointers anchored in the inode, with |
274 | * data blocks at leaves and indirect blocks in intermediate nodes. | |
275 | * This function translates the block number into path in that tree - | |
276 | * return value is the path length and @offsets[n] is the offset of | |
277 | * pointer to (n+1)th node in the nth one. If @block is out of range | |
278 | * (negative or too large) warning is printed and zero returned. | |
279 | * | |
280 | * Note: function doesn't find node addresses, so no IO is needed. All | |
281 | * we need to know is the capacity of indirect blocks (taken from the | |
282 | * inode->i_sb). | |
283 | */ | |
284 | ||
285 | /* | |
286 | * Portability note: the last comparison (check that we fit into triple | |
287 | * indirect block) is spelled differently, because otherwise on an | |
288 | * architecture with 32-bit longs and 8Kb pages we might get into trouble | |
289 | * if our filesystem had 8Kb blocks. We might use long long, but that would | |
290 | * kill us on x86. Oh, well, at least the sign propagation does not matter - | |
291 | * i_block would have to be negative in the very beginning, so we would not | |
292 | * get there at all. | |
293 | */ | |
294 | ||
617ba13b | 295 | static int ext4_block_to_path(struct inode *inode, |
de9a55b8 TT |
296 | ext4_lblk_t i_block, |
297 | ext4_lblk_t offsets[4], int *boundary) | |
ac27a0ec | 298 | { |
617ba13b MC |
299 | int ptrs = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
300 | int ptrs_bits = EXT4_ADDR_PER_BLOCK_BITS(inode->i_sb); | |
301 | const long direct_blocks = EXT4_NDIR_BLOCKS, | |
ac27a0ec DK |
302 | indirect_blocks = ptrs, |
303 | double_blocks = (1 << (ptrs_bits * 2)); | |
304 | int n = 0; | |
305 | int final = 0; | |
306 | ||
c333e073 | 307 | if (i_block < direct_blocks) { |
ac27a0ec DK |
308 | offsets[n++] = i_block; |
309 | final = direct_blocks; | |
af5bc92d | 310 | } else if ((i_block -= direct_blocks) < indirect_blocks) { |
617ba13b | 311 | offsets[n++] = EXT4_IND_BLOCK; |
ac27a0ec DK |
312 | offsets[n++] = i_block; |
313 | final = ptrs; | |
314 | } else if ((i_block -= indirect_blocks) < double_blocks) { | |
617ba13b | 315 | offsets[n++] = EXT4_DIND_BLOCK; |
ac27a0ec DK |
316 | offsets[n++] = i_block >> ptrs_bits; |
317 | offsets[n++] = i_block & (ptrs - 1); | |
318 | final = ptrs; | |
319 | } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) { | |
617ba13b | 320 | offsets[n++] = EXT4_TIND_BLOCK; |
ac27a0ec DK |
321 | offsets[n++] = i_block >> (ptrs_bits * 2); |
322 | offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1); | |
323 | offsets[n++] = i_block & (ptrs - 1); | |
324 | final = ptrs; | |
325 | } else { | |
e2b46574 | 326 | ext4_warning(inode->i_sb, "ext4_block_to_path", |
de9a55b8 TT |
327 | "block %lu > max in inode %lu", |
328 | i_block + direct_blocks + | |
329 | indirect_blocks + double_blocks, inode->i_ino); | |
ac27a0ec DK |
330 | } |
331 | if (boundary) | |
332 | *boundary = final - 1 - (i_block & (ptrs - 1)); | |
333 | return n; | |
334 | } | |
335 | ||
fe2c8191 | 336 | static int __ext4_check_blockref(const char *function, struct inode *inode, |
6fd058f7 TT |
337 | __le32 *p, unsigned int max) |
338 | { | |
f73953c0 | 339 | __le32 *bref = p; |
6fd058f7 TT |
340 | unsigned int blk; |
341 | ||
fe2c8191 | 342 | while (bref < p+max) { |
6fd058f7 | 343 | blk = le32_to_cpu(*bref++); |
de9a55b8 TT |
344 | if (blk && |
345 | unlikely(!ext4_data_block_valid(EXT4_SB(inode->i_sb), | |
6fd058f7 | 346 | blk, 1))) { |
fe2c8191 | 347 | ext4_error(inode->i_sb, function, |
6fd058f7 TT |
348 | "invalid block reference %u " |
349 | "in inode #%lu", blk, inode->i_ino); | |
de9a55b8 TT |
350 | return -EIO; |
351 | } | |
352 | } | |
353 | return 0; | |
fe2c8191 TN |
354 | } |
355 | ||
356 | ||
357 | #define ext4_check_indirect_blockref(inode, bh) \ | |
de9a55b8 | 358 | __ext4_check_blockref(__func__, inode, (__le32 *)(bh)->b_data, \ |
fe2c8191 TN |
359 | EXT4_ADDR_PER_BLOCK((inode)->i_sb)) |
360 | ||
361 | #define ext4_check_inode_blockref(inode) \ | |
de9a55b8 | 362 | __ext4_check_blockref(__func__, inode, EXT4_I(inode)->i_data, \ |
fe2c8191 TN |
363 | EXT4_NDIR_BLOCKS) |
364 | ||
ac27a0ec | 365 | /** |
617ba13b | 366 | * ext4_get_branch - read the chain of indirect blocks leading to data |
ac27a0ec DK |
367 | * @inode: inode in question |
368 | * @depth: depth of the chain (1 - direct pointer, etc.) | |
369 | * @offsets: offsets of pointers in inode/indirect blocks | |
370 | * @chain: place to store the result | |
371 | * @err: here we store the error value | |
372 | * | |
373 | * Function fills the array of triples <key, p, bh> and returns %NULL | |
374 | * if everything went OK or the pointer to the last filled triple | |
375 | * (incomplete one) otherwise. Upon the return chain[i].key contains | |
376 | * the number of (i+1)-th block in the chain (as it is stored in memory, | |
377 | * i.e. little-endian 32-bit), chain[i].p contains the address of that | |
378 | * number (it points into struct inode for i==0 and into the bh->b_data | |
379 | * for i>0) and chain[i].bh points to the buffer_head of i-th indirect | |
380 | * block for i>0 and NULL for i==0. In other words, it holds the block | |
381 | * numbers of the chain, addresses they were taken from (and where we can | |
382 | * verify that chain did not change) and buffer_heads hosting these | |
383 | * numbers. | |
384 | * | |
385 | * Function stops when it stumbles upon zero pointer (absent block) | |
386 | * (pointer to last triple returned, *@err == 0) | |
387 | * or when it gets an IO error reading an indirect block | |
388 | * (ditto, *@err == -EIO) | |
ac27a0ec DK |
389 | * or when it reads all @depth-1 indirect blocks successfully and finds |
390 | * the whole chain, all way to the data (returns %NULL, *err == 0). | |
c278bfec AK |
391 | * |
392 | * Need to be called with | |
0e855ac8 | 393 | * down_read(&EXT4_I(inode)->i_data_sem) |
ac27a0ec | 394 | */ |
725d26d3 AK |
395 | static Indirect *ext4_get_branch(struct inode *inode, int depth, |
396 | ext4_lblk_t *offsets, | |
ac27a0ec DK |
397 | Indirect chain[4], int *err) |
398 | { | |
399 | struct super_block *sb = inode->i_sb; | |
400 | Indirect *p = chain; | |
401 | struct buffer_head *bh; | |
402 | ||
403 | *err = 0; | |
404 | /* i_data is not going away, no lock needed */ | |
af5bc92d | 405 | add_chain(chain, NULL, EXT4_I(inode)->i_data + *offsets); |
ac27a0ec DK |
406 | if (!p->key) |
407 | goto no_block; | |
408 | while (--depth) { | |
fe2c8191 TN |
409 | bh = sb_getblk(sb, le32_to_cpu(p->key)); |
410 | if (unlikely(!bh)) | |
ac27a0ec | 411 | goto failure; |
de9a55b8 | 412 | |
fe2c8191 TN |
413 | if (!bh_uptodate_or_lock(bh)) { |
414 | if (bh_submit_read(bh) < 0) { | |
415 | put_bh(bh); | |
416 | goto failure; | |
417 | } | |
418 | /* validate block references */ | |
419 | if (ext4_check_indirect_blockref(inode, bh)) { | |
420 | put_bh(bh); | |
421 | goto failure; | |
422 | } | |
423 | } | |
de9a55b8 | 424 | |
af5bc92d | 425 | add_chain(++p, bh, (__le32 *)bh->b_data + *++offsets); |
ac27a0ec DK |
426 | /* Reader: end */ |
427 | if (!p->key) | |
428 | goto no_block; | |
429 | } | |
430 | return NULL; | |
431 | ||
ac27a0ec DK |
432 | failure: |
433 | *err = -EIO; | |
434 | no_block: | |
435 | return p; | |
436 | } | |
437 | ||
438 | /** | |
617ba13b | 439 | * ext4_find_near - find a place for allocation with sufficient locality |
ac27a0ec DK |
440 | * @inode: owner |
441 | * @ind: descriptor of indirect block. | |
442 | * | |
1cc8dcf5 | 443 | * This function returns the preferred place for block allocation. |
ac27a0ec DK |
444 | * It is used when heuristic for sequential allocation fails. |
445 | * Rules are: | |
446 | * + if there is a block to the left of our position - allocate near it. | |
447 | * + if pointer will live in indirect block - allocate near that block. | |
448 | * + if pointer will live in inode - allocate in the same | |
449 | * cylinder group. | |
450 | * | |
451 | * In the latter case we colour the starting block by the callers PID to | |
452 | * prevent it from clashing with concurrent allocations for a different inode | |
453 | * in the same block group. The PID is used here so that functionally related | |
454 | * files will be close-by on-disk. | |
455 | * | |
456 | * Caller must make sure that @ind is valid and will stay that way. | |
457 | */ | |
617ba13b | 458 | static ext4_fsblk_t ext4_find_near(struct inode *inode, Indirect *ind) |
ac27a0ec | 459 | { |
617ba13b | 460 | struct ext4_inode_info *ei = EXT4_I(inode); |
af5bc92d | 461 | __le32 *start = ind->bh ? (__le32 *) ind->bh->b_data : ei->i_data; |
ac27a0ec | 462 | __le32 *p; |
617ba13b | 463 | ext4_fsblk_t bg_start; |
74d3487f | 464 | ext4_fsblk_t last_block; |
617ba13b | 465 | ext4_grpblk_t colour; |
a4912123 TT |
466 | ext4_group_t block_group; |
467 | int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb)); | |
ac27a0ec DK |
468 | |
469 | /* Try to find previous block */ | |
470 | for (p = ind->p - 1; p >= start; p--) { | |
471 | if (*p) | |
472 | return le32_to_cpu(*p); | |
473 | } | |
474 | ||
475 | /* No such thing, so let's try location of indirect block */ | |
476 | if (ind->bh) | |
477 | return ind->bh->b_blocknr; | |
478 | ||
479 | /* | |
480 | * It is going to be referred to from the inode itself? OK, just put it | |
481 | * into the same cylinder group then. | |
482 | */ | |
a4912123 TT |
483 | block_group = ei->i_block_group; |
484 | if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) { | |
485 | block_group &= ~(flex_size-1); | |
486 | if (S_ISREG(inode->i_mode)) | |
487 | block_group++; | |
488 | } | |
489 | bg_start = ext4_group_first_block_no(inode->i_sb, block_group); | |
74d3487f VC |
490 | last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1; |
491 | ||
a4912123 TT |
492 | /* |
493 | * If we are doing delayed allocation, we don't need take | |
494 | * colour into account. | |
495 | */ | |
496 | if (test_opt(inode->i_sb, DELALLOC)) | |
497 | return bg_start; | |
498 | ||
74d3487f VC |
499 | if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block) |
500 | colour = (current->pid % 16) * | |
617ba13b | 501 | (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16); |
74d3487f VC |
502 | else |
503 | colour = (current->pid % 16) * ((last_block - bg_start) / 16); | |
ac27a0ec DK |
504 | return bg_start + colour; |
505 | } | |
506 | ||
507 | /** | |
1cc8dcf5 | 508 | * ext4_find_goal - find a preferred place for allocation. |
ac27a0ec DK |
509 | * @inode: owner |
510 | * @block: block we want | |
ac27a0ec | 511 | * @partial: pointer to the last triple within a chain |
ac27a0ec | 512 | * |
1cc8dcf5 | 513 | * Normally this function find the preferred place for block allocation, |
fb01bfda | 514 | * returns it. |
fb0a387d ES |
515 | * Because this is only used for non-extent files, we limit the block nr |
516 | * to 32 bits. | |
ac27a0ec | 517 | */ |
725d26d3 | 518 | static ext4_fsblk_t ext4_find_goal(struct inode *inode, ext4_lblk_t block, |
de9a55b8 | 519 | Indirect *partial) |
ac27a0ec | 520 | { |
fb0a387d ES |
521 | ext4_fsblk_t goal; |
522 | ||
ac27a0ec | 523 | /* |
c2ea3fde | 524 | * XXX need to get goal block from mballoc's data structures |
ac27a0ec | 525 | */ |
ac27a0ec | 526 | |
fb0a387d ES |
527 | goal = ext4_find_near(inode, partial); |
528 | goal = goal & EXT4_MAX_BLOCK_FILE_PHYS; | |
529 | return goal; | |
ac27a0ec DK |
530 | } |
531 | ||
532 | /** | |
617ba13b | 533 | * ext4_blks_to_allocate: Look up the block map and count the number |
ac27a0ec DK |
534 | * of direct blocks need to be allocated for the given branch. |
535 | * | |
536 | * @branch: chain of indirect blocks | |
537 | * @k: number of blocks need for indirect blocks | |
538 | * @blks: number of data blocks to be mapped. | |
539 | * @blocks_to_boundary: the offset in the indirect block | |
540 | * | |
541 | * return the total number of blocks to be allocate, including the | |
542 | * direct and indirect blocks. | |
543 | */ | |
498e5f24 | 544 | static int ext4_blks_to_allocate(Indirect *branch, int k, unsigned int blks, |
de9a55b8 | 545 | int blocks_to_boundary) |
ac27a0ec | 546 | { |
498e5f24 | 547 | unsigned int count = 0; |
ac27a0ec DK |
548 | |
549 | /* | |
550 | * Simple case, [t,d]Indirect block(s) has not allocated yet | |
551 | * then it's clear blocks on that path have not allocated | |
552 | */ | |
553 | if (k > 0) { | |
554 | /* right now we don't handle cross boundary allocation */ | |
555 | if (blks < blocks_to_boundary + 1) | |
556 | count += blks; | |
557 | else | |
558 | count += blocks_to_boundary + 1; | |
559 | return count; | |
560 | } | |
561 | ||
562 | count++; | |
563 | while (count < blks && count <= blocks_to_boundary && | |
564 | le32_to_cpu(*(branch[0].p + count)) == 0) { | |
565 | count++; | |
566 | } | |
567 | return count; | |
568 | } | |
569 | ||
570 | /** | |
617ba13b | 571 | * ext4_alloc_blocks: multiple allocate blocks needed for a branch |
ac27a0ec DK |
572 | * @indirect_blks: the number of blocks need to allocate for indirect |
573 | * blocks | |
574 | * | |
575 | * @new_blocks: on return it will store the new block numbers for | |
576 | * the indirect blocks(if needed) and the first direct block, | |
577 | * @blks: on return it will store the total number of allocated | |
578 | * direct blocks | |
579 | */ | |
617ba13b | 580 | static int ext4_alloc_blocks(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
581 | ext4_lblk_t iblock, ext4_fsblk_t goal, |
582 | int indirect_blks, int blks, | |
583 | ext4_fsblk_t new_blocks[4], int *err) | |
ac27a0ec | 584 | { |
815a1130 | 585 | struct ext4_allocation_request ar; |
ac27a0ec | 586 | int target, i; |
7061eba7 | 587 | unsigned long count = 0, blk_allocated = 0; |
ac27a0ec | 588 | int index = 0; |
617ba13b | 589 | ext4_fsblk_t current_block = 0; |
ac27a0ec DK |
590 | int ret = 0; |
591 | ||
592 | /* | |
593 | * Here we try to allocate the requested multiple blocks at once, | |
594 | * on a best-effort basis. | |
595 | * To build a branch, we should allocate blocks for | |
596 | * the indirect blocks(if not allocated yet), and at least | |
597 | * the first direct block of this branch. That's the | |
598 | * minimum number of blocks need to allocate(required) | |
599 | */ | |
7061eba7 AK |
600 | /* first we try to allocate the indirect blocks */ |
601 | target = indirect_blks; | |
602 | while (target > 0) { | |
ac27a0ec DK |
603 | count = target; |
604 | /* allocating blocks for indirect blocks and direct blocks */ | |
7061eba7 AK |
605 | current_block = ext4_new_meta_blocks(handle, inode, |
606 | goal, &count, err); | |
ac27a0ec DK |
607 | if (*err) |
608 | goto failed_out; | |
609 | ||
fb0a387d ES |
610 | BUG_ON(current_block + count > EXT4_MAX_BLOCK_FILE_PHYS); |
611 | ||
ac27a0ec DK |
612 | target -= count; |
613 | /* allocate blocks for indirect blocks */ | |
614 | while (index < indirect_blks && count) { | |
615 | new_blocks[index++] = current_block++; | |
616 | count--; | |
617 | } | |
7061eba7 AK |
618 | if (count > 0) { |
619 | /* | |
620 | * save the new block number | |
621 | * for the first direct block | |
622 | */ | |
623 | new_blocks[index] = current_block; | |
624 | printk(KERN_INFO "%s returned more blocks than " | |
625 | "requested\n", __func__); | |
626 | WARN_ON(1); | |
ac27a0ec | 627 | break; |
7061eba7 | 628 | } |
ac27a0ec DK |
629 | } |
630 | ||
7061eba7 AK |
631 | target = blks - count ; |
632 | blk_allocated = count; | |
633 | if (!target) | |
634 | goto allocated; | |
635 | /* Now allocate data blocks */ | |
815a1130 TT |
636 | memset(&ar, 0, sizeof(ar)); |
637 | ar.inode = inode; | |
638 | ar.goal = goal; | |
639 | ar.len = target; | |
640 | ar.logical = iblock; | |
641 | if (S_ISREG(inode->i_mode)) | |
642 | /* enable in-core preallocation only for regular files */ | |
643 | ar.flags = EXT4_MB_HINT_DATA; | |
644 | ||
645 | current_block = ext4_mb_new_blocks(handle, &ar, err); | |
fb0a387d | 646 | BUG_ON(current_block + ar.len > EXT4_MAX_BLOCK_FILE_PHYS); |
815a1130 | 647 | |
7061eba7 AK |
648 | if (*err && (target == blks)) { |
649 | /* | |
650 | * if the allocation failed and we didn't allocate | |
651 | * any blocks before | |
652 | */ | |
653 | goto failed_out; | |
654 | } | |
655 | if (!*err) { | |
656 | if (target == blks) { | |
de9a55b8 TT |
657 | /* |
658 | * save the new block number | |
659 | * for the first direct block | |
660 | */ | |
7061eba7 AK |
661 | new_blocks[index] = current_block; |
662 | } | |
815a1130 | 663 | blk_allocated += ar.len; |
7061eba7 AK |
664 | } |
665 | allocated: | |
ac27a0ec | 666 | /* total number of blocks allocated for direct blocks */ |
7061eba7 | 667 | ret = blk_allocated; |
ac27a0ec DK |
668 | *err = 0; |
669 | return ret; | |
670 | failed_out: | |
af5bc92d | 671 | for (i = 0; i < index; i++) |
e6362609 | 672 | ext4_free_blocks(handle, inode, 0, new_blocks[i], 1, 0); |
ac27a0ec DK |
673 | return ret; |
674 | } | |
675 | ||
676 | /** | |
617ba13b | 677 | * ext4_alloc_branch - allocate and set up a chain of blocks. |
ac27a0ec DK |
678 | * @inode: owner |
679 | * @indirect_blks: number of allocated indirect blocks | |
680 | * @blks: number of allocated direct blocks | |
681 | * @offsets: offsets (in the blocks) to store the pointers to next. | |
682 | * @branch: place to store the chain in. | |
683 | * | |
684 | * This function allocates blocks, zeroes out all but the last one, | |
685 | * links them into chain and (if we are synchronous) writes them to disk. | |
686 | * In other words, it prepares a branch that can be spliced onto the | |
687 | * inode. It stores the information about that chain in the branch[], in | |
617ba13b | 688 | * the same format as ext4_get_branch() would do. We are calling it after |
ac27a0ec DK |
689 | * we had read the existing part of chain and partial points to the last |
690 | * triple of that (one with zero ->key). Upon the exit we have the same | |
617ba13b | 691 | * picture as after the successful ext4_get_block(), except that in one |
ac27a0ec DK |
692 | * place chain is disconnected - *branch->p is still zero (we did not |
693 | * set the last link), but branch->key contains the number that should | |
694 | * be placed into *branch->p to fill that gap. | |
695 | * | |
696 | * If allocation fails we free all blocks we've allocated (and forget | |
697 | * their buffer_heads) and return the error value the from failed | |
617ba13b | 698 | * ext4_alloc_block() (normally -ENOSPC). Otherwise we set the chain |
ac27a0ec DK |
699 | * as described above and return 0. |
700 | */ | |
617ba13b | 701 | static int ext4_alloc_branch(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
702 | ext4_lblk_t iblock, int indirect_blks, |
703 | int *blks, ext4_fsblk_t goal, | |
704 | ext4_lblk_t *offsets, Indirect *branch) | |
ac27a0ec DK |
705 | { |
706 | int blocksize = inode->i_sb->s_blocksize; | |
707 | int i, n = 0; | |
708 | int err = 0; | |
709 | struct buffer_head *bh; | |
710 | int num; | |
617ba13b MC |
711 | ext4_fsblk_t new_blocks[4]; |
712 | ext4_fsblk_t current_block; | |
ac27a0ec | 713 | |
7061eba7 | 714 | num = ext4_alloc_blocks(handle, inode, iblock, goal, indirect_blks, |
ac27a0ec DK |
715 | *blks, new_blocks, &err); |
716 | if (err) | |
717 | return err; | |
718 | ||
719 | branch[0].key = cpu_to_le32(new_blocks[0]); | |
720 | /* | |
721 | * metadata blocks and data blocks are allocated. | |
722 | */ | |
723 | for (n = 1; n <= indirect_blks; n++) { | |
724 | /* | |
725 | * Get buffer_head for parent block, zero it out | |
726 | * and set the pointer to new one, then send | |
727 | * parent to disk. | |
728 | */ | |
729 | bh = sb_getblk(inode->i_sb, new_blocks[n-1]); | |
730 | branch[n].bh = bh; | |
731 | lock_buffer(bh); | |
732 | BUFFER_TRACE(bh, "call get_create_access"); | |
617ba13b | 733 | err = ext4_journal_get_create_access(handle, bh); |
ac27a0ec | 734 | if (err) { |
6487a9d3 CW |
735 | /* Don't brelse(bh) here; it's done in |
736 | * ext4_journal_forget() below */ | |
ac27a0ec | 737 | unlock_buffer(bh); |
ac27a0ec DK |
738 | goto failed; |
739 | } | |
740 | ||
741 | memset(bh->b_data, 0, blocksize); | |
742 | branch[n].p = (__le32 *) bh->b_data + offsets[n]; | |
743 | branch[n].key = cpu_to_le32(new_blocks[n]); | |
744 | *branch[n].p = branch[n].key; | |
af5bc92d | 745 | if (n == indirect_blks) { |
ac27a0ec DK |
746 | current_block = new_blocks[n]; |
747 | /* | |
748 | * End of chain, update the last new metablock of | |
749 | * the chain to point to the new allocated | |
750 | * data blocks numbers | |
751 | */ | |
de9a55b8 | 752 | for (i = 1; i < num; i++) |
ac27a0ec DK |
753 | *(branch[n].p + i) = cpu_to_le32(++current_block); |
754 | } | |
755 | BUFFER_TRACE(bh, "marking uptodate"); | |
756 | set_buffer_uptodate(bh); | |
757 | unlock_buffer(bh); | |
758 | ||
0390131b FM |
759 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
760 | err = ext4_handle_dirty_metadata(handle, inode, bh); | |
ac27a0ec DK |
761 | if (err) |
762 | goto failed; | |
763 | } | |
764 | *blks = num; | |
765 | return err; | |
766 | failed: | |
767 | /* Allocation failed, free what we already allocated */ | |
e6362609 | 768 | ext4_free_blocks(handle, inode, 0, new_blocks[0], 1, 0); |
ac27a0ec | 769 | for (i = 1; i <= n ; i++) { |
b7e57e7c | 770 | /* |
e6362609 TT |
771 | * branch[i].bh is newly allocated, so there is no |
772 | * need to revoke the block, which is why we don't | |
773 | * need to set EXT4_FREE_BLOCKS_METADATA. | |
b7e57e7c | 774 | */ |
e6362609 TT |
775 | ext4_free_blocks(handle, inode, 0, new_blocks[i], 1, |
776 | EXT4_FREE_BLOCKS_FORGET); | |
ac27a0ec | 777 | } |
e6362609 TT |
778 | for (i = n+1; i < indirect_blks; i++) |
779 | ext4_free_blocks(handle, inode, 0, new_blocks[i], 1, 0); | |
ac27a0ec | 780 | |
e6362609 | 781 | ext4_free_blocks(handle, inode, 0, new_blocks[i], num, 0); |
ac27a0ec DK |
782 | |
783 | return err; | |
784 | } | |
785 | ||
786 | /** | |
617ba13b | 787 | * ext4_splice_branch - splice the allocated branch onto inode. |
ac27a0ec DK |
788 | * @inode: owner |
789 | * @block: (logical) number of block we are adding | |
790 | * @chain: chain of indirect blocks (with a missing link - see | |
617ba13b | 791 | * ext4_alloc_branch) |
ac27a0ec DK |
792 | * @where: location of missing link |
793 | * @num: number of indirect blocks we are adding | |
794 | * @blks: number of direct blocks we are adding | |
795 | * | |
796 | * This function fills the missing link and does all housekeeping needed in | |
797 | * inode (->i_blocks, etc.). In case of success we end up with the full | |
798 | * chain to new block and return 0. | |
799 | */ | |
617ba13b | 800 | static int ext4_splice_branch(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
801 | ext4_lblk_t block, Indirect *where, int num, |
802 | int blks) | |
ac27a0ec DK |
803 | { |
804 | int i; | |
805 | int err = 0; | |
617ba13b | 806 | ext4_fsblk_t current_block; |
ac27a0ec | 807 | |
ac27a0ec DK |
808 | /* |
809 | * If we're splicing into a [td]indirect block (as opposed to the | |
810 | * inode) then we need to get write access to the [td]indirect block | |
811 | * before the splice. | |
812 | */ | |
813 | if (where->bh) { | |
814 | BUFFER_TRACE(where->bh, "get_write_access"); | |
617ba13b | 815 | err = ext4_journal_get_write_access(handle, where->bh); |
ac27a0ec DK |
816 | if (err) |
817 | goto err_out; | |
818 | } | |
819 | /* That's it */ | |
820 | ||
821 | *where->p = where->key; | |
822 | ||
823 | /* | |
824 | * Update the host buffer_head or inode to point to more just allocated | |
825 | * direct blocks blocks | |
826 | */ | |
827 | if (num == 0 && blks > 1) { | |
828 | current_block = le32_to_cpu(where->key) + 1; | |
829 | for (i = 1; i < blks; i++) | |
af5bc92d | 830 | *(where->p + i) = cpu_to_le32(current_block++); |
ac27a0ec DK |
831 | } |
832 | ||
ac27a0ec | 833 | /* We are done with atomic stuff, now do the rest of housekeeping */ |
ac27a0ec DK |
834 | /* had we spliced it onto indirect block? */ |
835 | if (where->bh) { | |
836 | /* | |
837 | * If we spliced it onto an indirect block, we haven't | |
838 | * altered the inode. Note however that if it is being spliced | |
839 | * onto an indirect block at the very end of the file (the | |
840 | * file is growing) then we *will* alter the inode to reflect | |
841 | * the new i_size. But that is not done here - it is done in | |
617ba13b | 842 | * generic_commit_write->__mark_inode_dirty->ext4_dirty_inode. |
ac27a0ec DK |
843 | */ |
844 | jbd_debug(5, "splicing indirect only\n"); | |
0390131b FM |
845 | BUFFER_TRACE(where->bh, "call ext4_handle_dirty_metadata"); |
846 | err = ext4_handle_dirty_metadata(handle, inode, where->bh); | |
ac27a0ec DK |
847 | if (err) |
848 | goto err_out; | |
849 | } else { | |
850 | /* | |
851 | * OK, we spliced it into the inode itself on a direct block. | |
ac27a0ec | 852 | */ |
41591750 | 853 | ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
854 | jbd_debug(5, "splicing direct\n"); |
855 | } | |
856 | return err; | |
857 | ||
858 | err_out: | |
859 | for (i = 1; i <= num; i++) { | |
b7e57e7c | 860 | /* |
e6362609 TT |
861 | * branch[i].bh is newly allocated, so there is no |
862 | * need to revoke the block, which is why we don't | |
863 | * need to set EXT4_FREE_BLOCKS_METADATA. | |
b7e57e7c | 864 | */ |
e6362609 TT |
865 | ext4_free_blocks(handle, inode, where[i].bh, 0, 1, |
866 | EXT4_FREE_BLOCKS_FORGET); | |
ac27a0ec | 867 | } |
e6362609 TT |
868 | ext4_free_blocks(handle, inode, 0, le32_to_cpu(where[num].key), |
869 | blks, 0); | |
ac27a0ec DK |
870 | |
871 | return err; | |
872 | } | |
873 | ||
874 | /* | |
b920c755 TT |
875 | * The ext4_ind_get_blocks() function handles non-extents inodes |
876 | * (i.e., using the traditional indirect/double-indirect i_blocks | |
877 | * scheme) for ext4_get_blocks(). | |
878 | * | |
ac27a0ec DK |
879 | * Allocation strategy is simple: if we have to allocate something, we will |
880 | * have to go the whole way to leaf. So let's do it before attaching anything | |
881 | * to tree, set linkage between the newborn blocks, write them if sync is | |
882 | * required, recheck the path, free and repeat if check fails, otherwise | |
883 | * set the last missing link (that will protect us from any truncate-generated | |
884 | * removals - all blocks on the path are immune now) and possibly force the | |
885 | * write on the parent block. | |
886 | * That has a nice additional property: no special recovery from the failed | |
887 | * allocations is needed - we simply release blocks and do not touch anything | |
888 | * reachable from inode. | |
889 | * | |
890 | * `handle' can be NULL if create == 0. | |
891 | * | |
ac27a0ec DK |
892 | * return > 0, # of blocks mapped or allocated. |
893 | * return = 0, if plain lookup failed. | |
894 | * return < 0, error case. | |
c278bfec | 895 | * |
b920c755 TT |
896 | * The ext4_ind_get_blocks() function should be called with |
897 | * down_write(&EXT4_I(inode)->i_data_sem) if allocating filesystem | |
898 | * blocks (i.e., flags has EXT4_GET_BLOCKS_CREATE set) or | |
899 | * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system | |
900 | * blocks. | |
ac27a0ec | 901 | */ |
e4d996ca | 902 | static int ext4_ind_get_blocks(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
903 | ext4_lblk_t iblock, unsigned int maxblocks, |
904 | struct buffer_head *bh_result, | |
905 | int flags) | |
ac27a0ec DK |
906 | { |
907 | int err = -EIO; | |
725d26d3 | 908 | ext4_lblk_t offsets[4]; |
ac27a0ec DK |
909 | Indirect chain[4]; |
910 | Indirect *partial; | |
617ba13b | 911 | ext4_fsblk_t goal; |
ac27a0ec DK |
912 | int indirect_blks; |
913 | int blocks_to_boundary = 0; | |
914 | int depth; | |
ac27a0ec | 915 | int count = 0; |
617ba13b | 916 | ext4_fsblk_t first_block = 0; |
ac27a0ec | 917 | |
a86c6181 | 918 | J_ASSERT(!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)); |
c2177057 | 919 | J_ASSERT(handle != NULL || (flags & EXT4_GET_BLOCKS_CREATE) == 0); |
725d26d3 | 920 | depth = ext4_block_to_path(inode, iblock, offsets, |
de9a55b8 | 921 | &blocks_to_boundary); |
ac27a0ec DK |
922 | |
923 | if (depth == 0) | |
924 | goto out; | |
925 | ||
617ba13b | 926 | partial = ext4_get_branch(inode, depth, offsets, chain, &err); |
ac27a0ec DK |
927 | |
928 | /* Simplest case - block found, no allocation needed */ | |
929 | if (!partial) { | |
930 | first_block = le32_to_cpu(chain[depth - 1].key); | |
931 | clear_buffer_new(bh_result); | |
932 | count++; | |
933 | /*map more blocks*/ | |
934 | while (count < maxblocks && count <= blocks_to_boundary) { | |
617ba13b | 935 | ext4_fsblk_t blk; |
ac27a0ec | 936 | |
ac27a0ec DK |
937 | blk = le32_to_cpu(*(chain[depth-1].p + count)); |
938 | ||
939 | if (blk == first_block + count) | |
940 | count++; | |
941 | else | |
942 | break; | |
943 | } | |
c278bfec | 944 | goto got_it; |
ac27a0ec DK |
945 | } |
946 | ||
947 | /* Next simple case - plain lookup or failed read of indirect block */ | |
c2177057 | 948 | if ((flags & EXT4_GET_BLOCKS_CREATE) == 0 || err == -EIO) |
ac27a0ec DK |
949 | goto cleanup; |
950 | ||
ac27a0ec | 951 | /* |
c2ea3fde | 952 | * Okay, we need to do block allocation. |
ac27a0ec | 953 | */ |
fb01bfda | 954 | goal = ext4_find_goal(inode, iblock, partial); |
ac27a0ec DK |
955 | |
956 | /* the number of blocks need to allocate for [d,t]indirect blocks */ | |
957 | indirect_blks = (chain + depth) - partial - 1; | |
958 | ||
959 | /* | |
960 | * Next look up the indirect map to count the totoal number of | |
961 | * direct blocks to allocate for this branch. | |
962 | */ | |
617ba13b | 963 | count = ext4_blks_to_allocate(partial, indirect_blks, |
ac27a0ec DK |
964 | maxblocks, blocks_to_boundary); |
965 | /* | |
617ba13b | 966 | * Block out ext4_truncate while we alter the tree |
ac27a0ec | 967 | */ |
7061eba7 | 968 | err = ext4_alloc_branch(handle, inode, iblock, indirect_blks, |
de9a55b8 TT |
969 | &count, goal, |
970 | offsets + (partial - chain), partial); | |
ac27a0ec DK |
971 | |
972 | /* | |
617ba13b | 973 | * The ext4_splice_branch call will free and forget any buffers |
ac27a0ec DK |
974 | * on the new chain if there is a failure, but that risks using |
975 | * up transaction credits, especially for bitmaps where the | |
976 | * credits cannot be returned. Can we handle this somehow? We | |
977 | * may need to return -EAGAIN upwards in the worst case. --sct | |
978 | */ | |
979 | if (!err) | |
617ba13b | 980 | err = ext4_splice_branch(handle, inode, iblock, |
de9a55b8 | 981 | partial, indirect_blks, count); |
2bba702d | 982 | if (err) |
ac27a0ec DK |
983 | goto cleanup; |
984 | ||
985 | set_buffer_new(bh_result); | |
986 | got_it: | |
987 | map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key)); | |
988 | if (count > blocks_to_boundary) | |
989 | set_buffer_boundary(bh_result); | |
990 | err = count; | |
991 | /* Clean up and exit */ | |
992 | partial = chain + depth - 1; /* the whole chain */ | |
993 | cleanup: | |
994 | while (partial > chain) { | |
995 | BUFFER_TRACE(partial->bh, "call brelse"); | |
996 | brelse(partial->bh); | |
997 | partial--; | |
998 | } | |
999 | BUFFER_TRACE(bh_result, "returned"); | |
1000 | out: | |
1001 | return err; | |
1002 | } | |
1003 | ||
60e58e0f MC |
1004 | qsize_t ext4_get_reserved_space(struct inode *inode) |
1005 | { | |
1006 | unsigned long long total; | |
1007 | ||
1008 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); | |
1009 | total = EXT4_I(inode)->i_reserved_data_blocks + | |
1010 | EXT4_I(inode)->i_reserved_meta_blocks; | |
1011 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
1012 | ||
8aa6790f | 1013 | return (total << inode->i_blkbits); |
60e58e0f | 1014 | } |
12219aea AK |
1015 | /* |
1016 | * Calculate the number of metadata blocks need to reserve | |
1017 | * to allocate @blocks for non extent file based file | |
1018 | */ | |
1019 | static int ext4_indirect_calc_metadata_amount(struct inode *inode, int blocks) | |
1020 | { | |
1021 | int icap = EXT4_ADDR_PER_BLOCK(inode->i_sb); | |
1022 | int ind_blks, dind_blks, tind_blks; | |
1023 | ||
1024 | /* number of new indirect blocks needed */ | |
1025 | ind_blks = (blocks + icap - 1) / icap; | |
1026 | ||
1027 | dind_blks = (ind_blks + icap - 1) / icap; | |
1028 | ||
1029 | tind_blks = 1; | |
1030 | ||
1031 | return ind_blks + dind_blks + tind_blks; | |
1032 | } | |
1033 | ||
1034 | /* | |
1035 | * Calculate the number of metadata blocks need to reserve | |
1036 | * to allocate given number of blocks | |
1037 | */ | |
1038 | static int ext4_calc_metadata_amount(struct inode *inode, int blocks) | |
1039 | { | |
cd213226 MC |
1040 | if (!blocks) |
1041 | return 0; | |
1042 | ||
12219aea AK |
1043 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) |
1044 | return ext4_ext_calc_metadata_amount(inode, blocks); | |
1045 | ||
1046 | return ext4_indirect_calc_metadata_amount(inode, blocks); | |
1047 | } | |
1048 | ||
1049 | static void ext4_da_update_reserve_space(struct inode *inode, int used) | |
1050 | { | |
1051 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
1052 | int total, mdb, mdb_free; | |
1053 | ||
1054 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); | |
1055 | /* recalculate the number of metablocks still need to be reserved */ | |
1056 | total = EXT4_I(inode)->i_reserved_data_blocks - used; | |
1057 | mdb = ext4_calc_metadata_amount(inode, total); | |
1058 | ||
1059 | /* figure out how many metablocks to release */ | |
1060 | BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks); | |
1061 | mdb_free = EXT4_I(inode)->i_reserved_meta_blocks - mdb; | |
1062 | ||
6bc6e63f AK |
1063 | if (mdb_free) { |
1064 | /* Account for allocated meta_blocks */ | |
1065 | mdb_free -= EXT4_I(inode)->i_allocated_meta_blocks; | |
1066 | ||
1067 | /* update fs dirty blocks counter */ | |
1068 | percpu_counter_sub(&sbi->s_dirtyblocks_counter, mdb_free); | |
1069 | EXT4_I(inode)->i_allocated_meta_blocks = 0; | |
1070 | EXT4_I(inode)->i_reserved_meta_blocks = mdb; | |
1071 | } | |
12219aea AK |
1072 | |
1073 | /* update per-inode reservations */ | |
1074 | BUG_ON(used > EXT4_I(inode)->i_reserved_data_blocks); | |
1075 | EXT4_I(inode)->i_reserved_data_blocks -= used; | |
12219aea | 1076 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
60e58e0f MC |
1077 | |
1078 | /* | |
1079 | * free those over-booking quota for metadata blocks | |
1080 | */ | |
60e58e0f MC |
1081 | if (mdb_free) |
1082 | vfs_dq_release_reservation_block(inode, mdb_free); | |
d6014301 AK |
1083 | |
1084 | /* | |
1085 | * If we have done all the pending block allocations and if | |
1086 | * there aren't any writers on the inode, we can discard the | |
1087 | * inode's preallocations. | |
1088 | */ | |
1089 | if (!total && (atomic_read(&inode->i_writecount) == 0)) | |
1090 | ext4_discard_preallocations(inode); | |
12219aea AK |
1091 | } |
1092 | ||
80e42468 TT |
1093 | static int check_block_validity(struct inode *inode, const char *msg, |
1094 | sector_t logical, sector_t phys, int len) | |
6fd058f7 TT |
1095 | { |
1096 | if (!ext4_data_block_valid(EXT4_SB(inode->i_sb), phys, len)) { | |
80e42468 | 1097 | ext4_error(inode->i_sb, msg, |
6fd058f7 TT |
1098 | "inode #%lu logical block %llu mapped to %llu " |
1099 | "(size %d)", inode->i_ino, | |
1100 | (unsigned long long) logical, | |
1101 | (unsigned long long) phys, len); | |
6fd058f7 TT |
1102 | return -EIO; |
1103 | } | |
1104 | return 0; | |
1105 | } | |
1106 | ||
55138e0b | 1107 | /* |
1f94533d TT |
1108 | * Return the number of contiguous dirty pages in a given inode |
1109 | * starting at page frame idx. | |
55138e0b TT |
1110 | */ |
1111 | static pgoff_t ext4_num_dirty_pages(struct inode *inode, pgoff_t idx, | |
1112 | unsigned int max_pages) | |
1113 | { | |
1114 | struct address_space *mapping = inode->i_mapping; | |
1115 | pgoff_t index; | |
1116 | struct pagevec pvec; | |
1117 | pgoff_t num = 0; | |
1118 | int i, nr_pages, done = 0; | |
1119 | ||
1120 | if (max_pages == 0) | |
1121 | return 0; | |
1122 | pagevec_init(&pvec, 0); | |
1123 | while (!done) { | |
1124 | index = idx; | |
1125 | nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, | |
1126 | PAGECACHE_TAG_DIRTY, | |
1127 | (pgoff_t)PAGEVEC_SIZE); | |
1128 | if (nr_pages == 0) | |
1129 | break; | |
1130 | for (i = 0; i < nr_pages; i++) { | |
1131 | struct page *page = pvec.pages[i]; | |
1132 | struct buffer_head *bh, *head; | |
1133 | ||
1134 | lock_page(page); | |
1135 | if (unlikely(page->mapping != mapping) || | |
1136 | !PageDirty(page) || | |
1137 | PageWriteback(page) || | |
1138 | page->index != idx) { | |
1139 | done = 1; | |
1140 | unlock_page(page); | |
1141 | break; | |
1142 | } | |
1f94533d TT |
1143 | if (page_has_buffers(page)) { |
1144 | bh = head = page_buffers(page); | |
1145 | do { | |
1146 | if (!buffer_delay(bh) && | |
1147 | !buffer_unwritten(bh)) | |
1148 | done = 1; | |
1149 | bh = bh->b_this_page; | |
1150 | } while (!done && (bh != head)); | |
1151 | } | |
55138e0b TT |
1152 | unlock_page(page); |
1153 | if (done) | |
1154 | break; | |
1155 | idx++; | |
1156 | num++; | |
1157 | if (num >= max_pages) | |
1158 | break; | |
1159 | } | |
1160 | pagevec_release(&pvec); | |
1161 | } | |
1162 | return num; | |
1163 | } | |
1164 | ||
f5ab0d1f | 1165 | /* |
12b7ac17 | 1166 | * The ext4_get_blocks() function tries to look up the requested blocks, |
2b2d6d01 | 1167 | * and returns if the blocks are already mapped. |
f5ab0d1f | 1168 | * |
f5ab0d1f MC |
1169 | * Otherwise it takes the write lock of the i_data_sem and allocate blocks |
1170 | * and store the allocated blocks in the result buffer head and mark it | |
1171 | * mapped. | |
1172 | * | |
1173 | * If file type is extents based, it will call ext4_ext_get_blocks(), | |
e4d996ca | 1174 | * Otherwise, call with ext4_ind_get_blocks() to handle indirect mapping |
f5ab0d1f MC |
1175 | * based files |
1176 | * | |
1177 | * On success, it returns the number of blocks being mapped or allocate. | |
1178 | * if create==0 and the blocks are pre-allocated and uninitialized block, | |
1179 | * the result buffer head is unmapped. If the create ==1, it will make sure | |
1180 | * the buffer head is mapped. | |
1181 | * | |
1182 | * It returns 0 if plain look up failed (blocks have not been allocated), in | |
1183 | * that casem, buffer head is unmapped | |
1184 | * | |
1185 | * It returns the error in case of allocation failure. | |
1186 | */ | |
12b7ac17 TT |
1187 | int ext4_get_blocks(handle_t *handle, struct inode *inode, sector_t block, |
1188 | unsigned int max_blocks, struct buffer_head *bh, | |
c2177057 | 1189 | int flags) |
0e855ac8 AK |
1190 | { |
1191 | int retval; | |
f5ab0d1f MC |
1192 | |
1193 | clear_buffer_mapped(bh); | |
2a8964d6 | 1194 | clear_buffer_unwritten(bh); |
f5ab0d1f | 1195 | |
0031462b MC |
1196 | ext_debug("ext4_get_blocks(): inode %lu, flag %d, max_blocks %u," |
1197 | "logical block %lu\n", inode->i_ino, flags, max_blocks, | |
1198 | (unsigned long)block); | |
4df3d265 | 1199 | /* |
b920c755 TT |
1200 | * Try to see if we can get the block without requesting a new |
1201 | * file system block. | |
4df3d265 AK |
1202 | */ |
1203 | down_read((&EXT4_I(inode)->i_data_sem)); | |
1204 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { | |
1205 | retval = ext4_ext_get_blocks(handle, inode, block, max_blocks, | |
c2177057 | 1206 | bh, 0); |
0e855ac8 | 1207 | } else { |
e4d996ca | 1208 | retval = ext4_ind_get_blocks(handle, inode, block, max_blocks, |
c2177057 | 1209 | bh, 0); |
0e855ac8 | 1210 | } |
4df3d265 | 1211 | up_read((&EXT4_I(inode)->i_data_sem)); |
f5ab0d1f | 1212 | |
6fd058f7 | 1213 | if (retval > 0 && buffer_mapped(bh)) { |
80e42468 TT |
1214 | int ret = check_block_validity(inode, "file system corruption", |
1215 | block, bh->b_blocknr, retval); | |
6fd058f7 TT |
1216 | if (ret != 0) |
1217 | return ret; | |
1218 | } | |
1219 | ||
f5ab0d1f | 1220 | /* If it is only a block(s) look up */ |
c2177057 | 1221 | if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) |
f5ab0d1f MC |
1222 | return retval; |
1223 | ||
1224 | /* | |
1225 | * Returns if the blocks have already allocated | |
1226 | * | |
1227 | * Note that if blocks have been preallocated | |
1228 | * ext4_ext_get_block() returns th create = 0 | |
1229 | * with buffer head unmapped. | |
1230 | */ | |
1231 | if (retval > 0 && buffer_mapped(bh)) | |
4df3d265 AK |
1232 | return retval; |
1233 | ||
2a8964d6 AK |
1234 | /* |
1235 | * When we call get_blocks without the create flag, the | |
1236 | * BH_Unwritten flag could have gotten set if the blocks | |
1237 | * requested were part of a uninitialized extent. We need to | |
1238 | * clear this flag now that we are committed to convert all or | |
1239 | * part of the uninitialized extent to be an initialized | |
1240 | * extent. This is because we need to avoid the combination | |
1241 | * of BH_Unwritten and BH_Mapped flags being simultaneously | |
1242 | * set on the buffer_head. | |
1243 | */ | |
1244 | clear_buffer_unwritten(bh); | |
1245 | ||
4df3d265 | 1246 | /* |
f5ab0d1f MC |
1247 | * New blocks allocate and/or writing to uninitialized extent |
1248 | * will possibly result in updating i_data, so we take | |
1249 | * the write lock of i_data_sem, and call get_blocks() | |
1250 | * with create == 1 flag. | |
4df3d265 AK |
1251 | */ |
1252 | down_write((&EXT4_I(inode)->i_data_sem)); | |
d2a17637 MC |
1253 | |
1254 | /* | |
1255 | * if the caller is from delayed allocation writeout path | |
1256 | * we have already reserved fs blocks for allocation | |
1257 | * let the underlying get_block() function know to | |
1258 | * avoid double accounting | |
1259 | */ | |
c2177057 | 1260 | if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) |
d2a17637 | 1261 | EXT4_I(inode)->i_delalloc_reserved_flag = 1; |
4df3d265 AK |
1262 | /* |
1263 | * We need to check for EXT4 here because migrate | |
1264 | * could have changed the inode type in between | |
1265 | */ | |
0e855ac8 AK |
1266 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { |
1267 | retval = ext4_ext_get_blocks(handle, inode, block, max_blocks, | |
c2177057 | 1268 | bh, flags); |
0e855ac8 | 1269 | } else { |
e4d996ca | 1270 | retval = ext4_ind_get_blocks(handle, inode, block, |
c2177057 | 1271 | max_blocks, bh, flags); |
267e4db9 AK |
1272 | |
1273 | if (retval > 0 && buffer_new(bh)) { | |
1274 | /* | |
1275 | * We allocated new blocks which will result in | |
1276 | * i_data's format changing. Force the migrate | |
1277 | * to fail by clearing migrate flags | |
1278 | */ | |
1b9c12f4 | 1279 | EXT4_I(inode)->i_state &= ~EXT4_STATE_EXT_MIGRATE; |
267e4db9 | 1280 | } |
0e855ac8 | 1281 | } |
d2a17637 | 1282 | |
2ac3b6e0 | 1283 | if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) |
d2a17637 | 1284 | EXT4_I(inode)->i_delalloc_reserved_flag = 0; |
2ac3b6e0 TT |
1285 | |
1286 | /* | |
1287 | * Update reserved blocks/metadata blocks after successful | |
1288 | * block allocation which had been deferred till now. | |
1289 | */ | |
1290 | if ((retval > 0) && (flags & EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE)) | |
1291 | ext4_da_update_reserve_space(inode, retval); | |
d2a17637 | 1292 | |
4df3d265 | 1293 | up_write((&EXT4_I(inode)->i_data_sem)); |
6fd058f7 | 1294 | if (retval > 0 && buffer_mapped(bh)) { |
80e42468 TT |
1295 | int ret = check_block_validity(inode, "file system " |
1296 | "corruption after allocation", | |
1297 | block, bh->b_blocknr, retval); | |
6fd058f7 TT |
1298 | if (ret != 0) |
1299 | return ret; | |
1300 | } | |
0e855ac8 AK |
1301 | return retval; |
1302 | } | |
1303 | ||
f3bd1f3f MC |
1304 | /* Maximum number of blocks we map for direct IO at once. */ |
1305 | #define DIO_MAX_BLOCKS 4096 | |
1306 | ||
6873fa0d ES |
1307 | int ext4_get_block(struct inode *inode, sector_t iblock, |
1308 | struct buffer_head *bh_result, int create) | |
ac27a0ec | 1309 | { |
3e4fdaf8 | 1310 | handle_t *handle = ext4_journal_current_handle(); |
7fb5409d | 1311 | int ret = 0, started = 0; |
ac27a0ec | 1312 | unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; |
f3bd1f3f | 1313 | int dio_credits; |
ac27a0ec | 1314 | |
7fb5409d JK |
1315 | if (create && !handle) { |
1316 | /* Direct IO write... */ | |
1317 | if (max_blocks > DIO_MAX_BLOCKS) | |
1318 | max_blocks = DIO_MAX_BLOCKS; | |
f3bd1f3f MC |
1319 | dio_credits = ext4_chunk_trans_blocks(inode, max_blocks); |
1320 | handle = ext4_journal_start(inode, dio_credits); | |
7fb5409d | 1321 | if (IS_ERR(handle)) { |
ac27a0ec | 1322 | ret = PTR_ERR(handle); |
7fb5409d | 1323 | goto out; |
ac27a0ec | 1324 | } |
7fb5409d | 1325 | started = 1; |
ac27a0ec DK |
1326 | } |
1327 | ||
12b7ac17 | 1328 | ret = ext4_get_blocks(handle, inode, iblock, max_blocks, bh_result, |
c2177057 | 1329 | create ? EXT4_GET_BLOCKS_CREATE : 0); |
7fb5409d JK |
1330 | if (ret > 0) { |
1331 | bh_result->b_size = (ret << inode->i_blkbits); | |
1332 | ret = 0; | |
ac27a0ec | 1333 | } |
7fb5409d JK |
1334 | if (started) |
1335 | ext4_journal_stop(handle); | |
1336 | out: | |
ac27a0ec DK |
1337 | return ret; |
1338 | } | |
1339 | ||
1340 | /* | |
1341 | * `handle' can be NULL if create is zero | |
1342 | */ | |
617ba13b | 1343 | struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode, |
725d26d3 | 1344 | ext4_lblk_t block, int create, int *errp) |
ac27a0ec DK |
1345 | { |
1346 | struct buffer_head dummy; | |
1347 | int fatal = 0, err; | |
03f5d8bc | 1348 | int flags = 0; |
ac27a0ec DK |
1349 | |
1350 | J_ASSERT(handle != NULL || create == 0); | |
1351 | ||
1352 | dummy.b_state = 0; | |
1353 | dummy.b_blocknr = -1000; | |
1354 | buffer_trace_init(&dummy.b_history); | |
c2177057 TT |
1355 | if (create) |
1356 | flags |= EXT4_GET_BLOCKS_CREATE; | |
1357 | err = ext4_get_blocks(handle, inode, block, 1, &dummy, flags); | |
ac27a0ec | 1358 | /* |
c2177057 TT |
1359 | * ext4_get_blocks() returns number of blocks mapped. 0 in |
1360 | * case of a HOLE. | |
ac27a0ec DK |
1361 | */ |
1362 | if (err > 0) { | |
1363 | if (err > 1) | |
1364 | WARN_ON(1); | |
1365 | err = 0; | |
1366 | } | |
1367 | *errp = err; | |
1368 | if (!err && buffer_mapped(&dummy)) { | |
1369 | struct buffer_head *bh; | |
1370 | bh = sb_getblk(inode->i_sb, dummy.b_blocknr); | |
1371 | if (!bh) { | |
1372 | *errp = -EIO; | |
1373 | goto err; | |
1374 | } | |
1375 | if (buffer_new(&dummy)) { | |
1376 | J_ASSERT(create != 0); | |
ac39849d | 1377 | J_ASSERT(handle != NULL); |
ac27a0ec DK |
1378 | |
1379 | /* | |
1380 | * Now that we do not always journal data, we should | |
1381 | * keep in mind whether this should always journal the | |
1382 | * new buffer as metadata. For now, regular file | |
617ba13b | 1383 | * writes use ext4_get_block instead, so it's not a |
ac27a0ec DK |
1384 | * problem. |
1385 | */ | |
1386 | lock_buffer(bh); | |
1387 | BUFFER_TRACE(bh, "call get_create_access"); | |
617ba13b | 1388 | fatal = ext4_journal_get_create_access(handle, bh); |
ac27a0ec | 1389 | if (!fatal && !buffer_uptodate(bh)) { |
af5bc92d | 1390 | memset(bh->b_data, 0, inode->i_sb->s_blocksize); |
ac27a0ec DK |
1391 | set_buffer_uptodate(bh); |
1392 | } | |
1393 | unlock_buffer(bh); | |
0390131b FM |
1394 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
1395 | err = ext4_handle_dirty_metadata(handle, inode, bh); | |
ac27a0ec DK |
1396 | if (!fatal) |
1397 | fatal = err; | |
1398 | } else { | |
1399 | BUFFER_TRACE(bh, "not a new buffer"); | |
1400 | } | |
1401 | if (fatal) { | |
1402 | *errp = fatal; | |
1403 | brelse(bh); | |
1404 | bh = NULL; | |
1405 | } | |
1406 | return bh; | |
1407 | } | |
1408 | err: | |
1409 | return NULL; | |
1410 | } | |
1411 | ||
617ba13b | 1412 | struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode, |
725d26d3 | 1413 | ext4_lblk_t block, int create, int *err) |
ac27a0ec | 1414 | { |
af5bc92d | 1415 | struct buffer_head *bh; |
ac27a0ec | 1416 | |
617ba13b | 1417 | bh = ext4_getblk(handle, inode, block, create, err); |
ac27a0ec DK |
1418 | if (!bh) |
1419 | return bh; | |
1420 | if (buffer_uptodate(bh)) | |
1421 | return bh; | |
1422 | ll_rw_block(READ_META, 1, &bh); | |
1423 | wait_on_buffer(bh); | |
1424 | if (buffer_uptodate(bh)) | |
1425 | return bh; | |
1426 | put_bh(bh); | |
1427 | *err = -EIO; | |
1428 | return NULL; | |
1429 | } | |
1430 | ||
af5bc92d TT |
1431 | static int walk_page_buffers(handle_t *handle, |
1432 | struct buffer_head *head, | |
1433 | unsigned from, | |
1434 | unsigned to, | |
1435 | int *partial, | |
1436 | int (*fn)(handle_t *handle, | |
1437 | struct buffer_head *bh)) | |
ac27a0ec DK |
1438 | { |
1439 | struct buffer_head *bh; | |
1440 | unsigned block_start, block_end; | |
1441 | unsigned blocksize = head->b_size; | |
1442 | int err, ret = 0; | |
1443 | struct buffer_head *next; | |
1444 | ||
af5bc92d TT |
1445 | for (bh = head, block_start = 0; |
1446 | ret == 0 && (bh != head || !block_start); | |
de9a55b8 | 1447 | block_start = block_end, bh = next) { |
ac27a0ec DK |
1448 | next = bh->b_this_page; |
1449 | block_end = block_start + blocksize; | |
1450 | if (block_end <= from || block_start >= to) { | |
1451 | if (partial && !buffer_uptodate(bh)) | |
1452 | *partial = 1; | |
1453 | continue; | |
1454 | } | |
1455 | err = (*fn)(handle, bh); | |
1456 | if (!ret) | |
1457 | ret = err; | |
1458 | } | |
1459 | return ret; | |
1460 | } | |
1461 | ||
1462 | /* | |
1463 | * To preserve ordering, it is essential that the hole instantiation and | |
1464 | * the data write be encapsulated in a single transaction. We cannot | |
617ba13b | 1465 | * close off a transaction and start a new one between the ext4_get_block() |
dab291af | 1466 | * and the commit_write(). So doing the jbd2_journal_start at the start of |
ac27a0ec DK |
1467 | * prepare_write() is the right place. |
1468 | * | |
617ba13b MC |
1469 | * Also, this function can nest inside ext4_writepage() -> |
1470 | * block_write_full_page(). In that case, we *know* that ext4_writepage() | |
ac27a0ec DK |
1471 | * has generated enough buffer credits to do the whole page. So we won't |
1472 | * block on the journal in that case, which is good, because the caller may | |
1473 | * be PF_MEMALLOC. | |
1474 | * | |
617ba13b | 1475 | * By accident, ext4 can be reentered when a transaction is open via |
ac27a0ec DK |
1476 | * quota file writes. If we were to commit the transaction while thus |
1477 | * reentered, there can be a deadlock - we would be holding a quota | |
1478 | * lock, and the commit would never complete if another thread had a | |
1479 | * transaction open and was blocking on the quota lock - a ranking | |
1480 | * violation. | |
1481 | * | |
dab291af | 1482 | * So what we do is to rely on the fact that jbd2_journal_stop/journal_start |
ac27a0ec DK |
1483 | * will _not_ run commit under these circumstances because handle->h_ref |
1484 | * is elevated. We'll still have enough credits for the tiny quotafile | |
1485 | * write. | |
1486 | */ | |
1487 | static int do_journal_get_write_access(handle_t *handle, | |
de9a55b8 | 1488 | struct buffer_head *bh) |
ac27a0ec DK |
1489 | { |
1490 | if (!buffer_mapped(bh) || buffer_freed(bh)) | |
1491 | return 0; | |
617ba13b | 1492 | return ext4_journal_get_write_access(handle, bh); |
ac27a0ec DK |
1493 | } |
1494 | ||
b9a4207d JK |
1495 | /* |
1496 | * Truncate blocks that were not used by write. We have to truncate the | |
1497 | * pagecache as well so that corresponding buffers get properly unmapped. | |
1498 | */ | |
1499 | static void ext4_truncate_failed_write(struct inode *inode) | |
1500 | { | |
1501 | truncate_inode_pages(inode->i_mapping, inode->i_size); | |
1502 | ext4_truncate(inode); | |
1503 | } | |
1504 | ||
bfc1af65 | 1505 | static int ext4_write_begin(struct file *file, struct address_space *mapping, |
de9a55b8 TT |
1506 | loff_t pos, unsigned len, unsigned flags, |
1507 | struct page **pagep, void **fsdata) | |
ac27a0ec | 1508 | { |
af5bc92d | 1509 | struct inode *inode = mapping->host; |
1938a150 | 1510 | int ret, needed_blocks; |
ac27a0ec DK |
1511 | handle_t *handle; |
1512 | int retries = 0; | |
af5bc92d | 1513 | struct page *page; |
de9a55b8 | 1514 | pgoff_t index; |
af5bc92d | 1515 | unsigned from, to; |
bfc1af65 | 1516 | |
9bffad1e | 1517 | trace_ext4_write_begin(inode, pos, len, flags); |
1938a150 AK |
1518 | /* |
1519 | * Reserve one block more for addition to orphan list in case | |
1520 | * we allocate blocks but write fails for some reason | |
1521 | */ | |
1522 | needed_blocks = ext4_writepage_trans_blocks(inode) + 1; | |
de9a55b8 | 1523 | index = pos >> PAGE_CACHE_SHIFT; |
af5bc92d TT |
1524 | from = pos & (PAGE_CACHE_SIZE - 1); |
1525 | to = from + len; | |
ac27a0ec DK |
1526 | |
1527 | retry: | |
af5bc92d TT |
1528 | handle = ext4_journal_start(inode, needed_blocks); |
1529 | if (IS_ERR(handle)) { | |
1530 | ret = PTR_ERR(handle); | |
1531 | goto out; | |
7479d2b9 | 1532 | } |
ac27a0ec | 1533 | |
ebd3610b JK |
1534 | /* We cannot recurse into the filesystem as the transaction is already |
1535 | * started */ | |
1536 | flags |= AOP_FLAG_NOFS; | |
1537 | ||
54566b2c | 1538 | page = grab_cache_page_write_begin(mapping, index, flags); |
cf108bca JK |
1539 | if (!page) { |
1540 | ext4_journal_stop(handle); | |
1541 | ret = -ENOMEM; | |
1542 | goto out; | |
1543 | } | |
1544 | *pagep = page; | |
1545 | ||
bfc1af65 | 1546 | ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, |
ebd3610b | 1547 | ext4_get_block); |
bfc1af65 NP |
1548 | |
1549 | if (!ret && ext4_should_journal_data(inode)) { | |
ac27a0ec DK |
1550 | ret = walk_page_buffers(handle, page_buffers(page), |
1551 | from, to, NULL, do_journal_get_write_access); | |
1552 | } | |
bfc1af65 NP |
1553 | |
1554 | if (ret) { | |
af5bc92d | 1555 | unlock_page(page); |
af5bc92d | 1556 | page_cache_release(page); |
ae4d5372 AK |
1557 | /* |
1558 | * block_write_begin may have instantiated a few blocks | |
1559 | * outside i_size. Trim these off again. Don't need | |
1560 | * i_size_read because we hold i_mutex. | |
1938a150 AK |
1561 | * |
1562 | * Add inode to orphan list in case we crash before | |
1563 | * truncate finishes | |
ae4d5372 | 1564 | */ |
ffacfa7a | 1565 | if (pos + len > inode->i_size && ext4_can_truncate(inode)) |
1938a150 AK |
1566 | ext4_orphan_add(handle, inode); |
1567 | ||
1568 | ext4_journal_stop(handle); | |
1569 | if (pos + len > inode->i_size) { | |
b9a4207d | 1570 | ext4_truncate_failed_write(inode); |
de9a55b8 | 1571 | /* |
ffacfa7a | 1572 | * If truncate failed early the inode might |
1938a150 AK |
1573 | * still be on the orphan list; we need to |
1574 | * make sure the inode is removed from the | |
1575 | * orphan list in that case. | |
1576 | */ | |
1577 | if (inode->i_nlink) | |
1578 | ext4_orphan_del(NULL, inode); | |
1579 | } | |
bfc1af65 NP |
1580 | } |
1581 | ||
617ba13b | 1582 | if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) |
ac27a0ec | 1583 | goto retry; |
7479d2b9 | 1584 | out: |
ac27a0ec DK |
1585 | return ret; |
1586 | } | |
1587 | ||
bfc1af65 NP |
1588 | /* For write_end() in data=journal mode */ |
1589 | static int write_end_fn(handle_t *handle, struct buffer_head *bh) | |
ac27a0ec DK |
1590 | { |
1591 | if (!buffer_mapped(bh) || buffer_freed(bh)) | |
1592 | return 0; | |
1593 | set_buffer_uptodate(bh); | |
0390131b | 1594 | return ext4_handle_dirty_metadata(handle, NULL, bh); |
ac27a0ec DK |
1595 | } |
1596 | ||
f8514083 | 1597 | static int ext4_generic_write_end(struct file *file, |
de9a55b8 TT |
1598 | struct address_space *mapping, |
1599 | loff_t pos, unsigned len, unsigned copied, | |
1600 | struct page *page, void *fsdata) | |
f8514083 AK |
1601 | { |
1602 | int i_size_changed = 0; | |
1603 | struct inode *inode = mapping->host; | |
1604 | handle_t *handle = ext4_journal_current_handle(); | |
1605 | ||
1606 | copied = block_write_end(file, mapping, pos, len, copied, page, fsdata); | |
1607 | ||
1608 | /* | |
1609 | * No need to use i_size_read() here, the i_size | |
1610 | * cannot change under us because we hold i_mutex. | |
1611 | * | |
1612 | * But it's important to update i_size while still holding page lock: | |
1613 | * page writeout could otherwise come in and zero beyond i_size. | |
1614 | */ | |
1615 | if (pos + copied > inode->i_size) { | |
1616 | i_size_write(inode, pos + copied); | |
1617 | i_size_changed = 1; | |
1618 | } | |
1619 | ||
1620 | if (pos + copied > EXT4_I(inode)->i_disksize) { | |
1621 | /* We need to mark inode dirty even if | |
1622 | * new_i_size is less that inode->i_size | |
1623 | * bu greater than i_disksize.(hint delalloc) | |
1624 | */ | |
1625 | ext4_update_i_disksize(inode, (pos + copied)); | |
1626 | i_size_changed = 1; | |
1627 | } | |
1628 | unlock_page(page); | |
1629 | page_cache_release(page); | |
1630 | ||
1631 | /* | |
1632 | * Don't mark the inode dirty under page lock. First, it unnecessarily | |
1633 | * makes the holding time of page lock longer. Second, it forces lock | |
1634 | * ordering of page lock and transaction start for journaling | |
1635 | * filesystems. | |
1636 | */ | |
1637 | if (i_size_changed) | |
1638 | ext4_mark_inode_dirty(handle, inode); | |
1639 | ||
1640 | return copied; | |
1641 | } | |
1642 | ||
ac27a0ec DK |
1643 | /* |
1644 | * We need to pick up the new inode size which generic_commit_write gave us | |
1645 | * `file' can be NULL - eg, when called from page_symlink(). | |
1646 | * | |
617ba13b | 1647 | * ext4 never places buffers on inode->i_mapping->private_list. metadata |
ac27a0ec DK |
1648 | * buffers are managed internally. |
1649 | */ | |
bfc1af65 | 1650 | static int ext4_ordered_write_end(struct file *file, |
de9a55b8 TT |
1651 | struct address_space *mapping, |
1652 | loff_t pos, unsigned len, unsigned copied, | |
1653 | struct page *page, void *fsdata) | |
ac27a0ec | 1654 | { |
617ba13b | 1655 | handle_t *handle = ext4_journal_current_handle(); |
cf108bca | 1656 | struct inode *inode = mapping->host; |
ac27a0ec DK |
1657 | int ret = 0, ret2; |
1658 | ||
9bffad1e | 1659 | trace_ext4_ordered_write_end(inode, pos, len, copied); |
678aaf48 | 1660 | ret = ext4_jbd2_file_inode(handle, inode); |
ac27a0ec DK |
1661 | |
1662 | if (ret == 0) { | |
f8514083 | 1663 | ret2 = ext4_generic_write_end(file, mapping, pos, len, copied, |
bfc1af65 | 1664 | page, fsdata); |
f8a87d89 | 1665 | copied = ret2; |
ffacfa7a | 1666 | if (pos + len > inode->i_size && ext4_can_truncate(inode)) |
f8514083 AK |
1667 | /* if we have allocated more blocks and copied |
1668 | * less. We will have blocks allocated outside | |
1669 | * inode->i_size. So truncate them | |
1670 | */ | |
1671 | ext4_orphan_add(handle, inode); | |
f8a87d89 RK |
1672 | if (ret2 < 0) |
1673 | ret = ret2; | |
ac27a0ec | 1674 | } |
617ba13b | 1675 | ret2 = ext4_journal_stop(handle); |
ac27a0ec DK |
1676 | if (!ret) |
1677 | ret = ret2; | |
bfc1af65 | 1678 | |
f8514083 | 1679 | if (pos + len > inode->i_size) { |
b9a4207d | 1680 | ext4_truncate_failed_write(inode); |
de9a55b8 | 1681 | /* |
ffacfa7a | 1682 | * If truncate failed early the inode might still be |
f8514083 AK |
1683 | * on the orphan list; we need to make sure the inode |
1684 | * is removed from the orphan list in that case. | |
1685 | */ | |
1686 | if (inode->i_nlink) | |
1687 | ext4_orphan_del(NULL, inode); | |
1688 | } | |
1689 | ||
1690 | ||
bfc1af65 | 1691 | return ret ? ret : copied; |
ac27a0ec DK |
1692 | } |
1693 | ||
bfc1af65 | 1694 | static int ext4_writeback_write_end(struct file *file, |
de9a55b8 TT |
1695 | struct address_space *mapping, |
1696 | loff_t pos, unsigned len, unsigned copied, | |
1697 | struct page *page, void *fsdata) | |
ac27a0ec | 1698 | { |
617ba13b | 1699 | handle_t *handle = ext4_journal_current_handle(); |
cf108bca | 1700 | struct inode *inode = mapping->host; |
ac27a0ec | 1701 | int ret = 0, ret2; |
ac27a0ec | 1702 | |
9bffad1e | 1703 | trace_ext4_writeback_write_end(inode, pos, len, copied); |
f8514083 | 1704 | ret2 = ext4_generic_write_end(file, mapping, pos, len, copied, |
bfc1af65 | 1705 | page, fsdata); |
f8a87d89 | 1706 | copied = ret2; |
ffacfa7a | 1707 | if (pos + len > inode->i_size && ext4_can_truncate(inode)) |
f8514083 AK |
1708 | /* if we have allocated more blocks and copied |
1709 | * less. We will have blocks allocated outside | |
1710 | * inode->i_size. So truncate them | |
1711 | */ | |
1712 | ext4_orphan_add(handle, inode); | |
1713 | ||
f8a87d89 RK |
1714 | if (ret2 < 0) |
1715 | ret = ret2; | |
ac27a0ec | 1716 | |
617ba13b | 1717 | ret2 = ext4_journal_stop(handle); |
ac27a0ec DK |
1718 | if (!ret) |
1719 | ret = ret2; | |
bfc1af65 | 1720 | |
f8514083 | 1721 | if (pos + len > inode->i_size) { |
b9a4207d | 1722 | ext4_truncate_failed_write(inode); |
de9a55b8 | 1723 | /* |
ffacfa7a | 1724 | * If truncate failed early the inode might still be |
f8514083 AK |
1725 | * on the orphan list; we need to make sure the inode |
1726 | * is removed from the orphan list in that case. | |
1727 | */ | |
1728 | if (inode->i_nlink) | |
1729 | ext4_orphan_del(NULL, inode); | |
1730 | } | |
1731 | ||
bfc1af65 | 1732 | return ret ? ret : copied; |
ac27a0ec DK |
1733 | } |
1734 | ||
bfc1af65 | 1735 | static int ext4_journalled_write_end(struct file *file, |
de9a55b8 TT |
1736 | struct address_space *mapping, |
1737 | loff_t pos, unsigned len, unsigned copied, | |
1738 | struct page *page, void *fsdata) | |
ac27a0ec | 1739 | { |
617ba13b | 1740 | handle_t *handle = ext4_journal_current_handle(); |
bfc1af65 | 1741 | struct inode *inode = mapping->host; |
ac27a0ec DK |
1742 | int ret = 0, ret2; |
1743 | int partial = 0; | |
bfc1af65 | 1744 | unsigned from, to; |
cf17fea6 | 1745 | loff_t new_i_size; |
ac27a0ec | 1746 | |
9bffad1e | 1747 | trace_ext4_journalled_write_end(inode, pos, len, copied); |
bfc1af65 NP |
1748 | from = pos & (PAGE_CACHE_SIZE - 1); |
1749 | to = from + len; | |
1750 | ||
1751 | if (copied < len) { | |
1752 | if (!PageUptodate(page)) | |
1753 | copied = 0; | |
1754 | page_zero_new_buffers(page, from+copied, to); | |
1755 | } | |
ac27a0ec DK |
1756 | |
1757 | ret = walk_page_buffers(handle, page_buffers(page), from, | |
bfc1af65 | 1758 | to, &partial, write_end_fn); |
ac27a0ec DK |
1759 | if (!partial) |
1760 | SetPageUptodate(page); | |
cf17fea6 AK |
1761 | new_i_size = pos + copied; |
1762 | if (new_i_size > inode->i_size) | |
bfc1af65 | 1763 | i_size_write(inode, pos+copied); |
617ba13b | 1764 | EXT4_I(inode)->i_state |= EXT4_STATE_JDATA; |
cf17fea6 AK |
1765 | if (new_i_size > EXT4_I(inode)->i_disksize) { |
1766 | ext4_update_i_disksize(inode, new_i_size); | |
617ba13b | 1767 | ret2 = ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
1768 | if (!ret) |
1769 | ret = ret2; | |
1770 | } | |
bfc1af65 | 1771 | |
cf108bca | 1772 | unlock_page(page); |
f8514083 | 1773 | page_cache_release(page); |
ffacfa7a | 1774 | if (pos + len > inode->i_size && ext4_can_truncate(inode)) |
f8514083 AK |
1775 | /* if we have allocated more blocks and copied |
1776 | * less. We will have blocks allocated outside | |
1777 | * inode->i_size. So truncate them | |
1778 | */ | |
1779 | ext4_orphan_add(handle, inode); | |
1780 | ||
617ba13b | 1781 | ret2 = ext4_journal_stop(handle); |
ac27a0ec DK |
1782 | if (!ret) |
1783 | ret = ret2; | |
f8514083 | 1784 | if (pos + len > inode->i_size) { |
b9a4207d | 1785 | ext4_truncate_failed_write(inode); |
de9a55b8 | 1786 | /* |
ffacfa7a | 1787 | * If truncate failed early the inode might still be |
f8514083 AK |
1788 | * on the orphan list; we need to make sure the inode |
1789 | * is removed from the orphan list in that case. | |
1790 | */ | |
1791 | if (inode->i_nlink) | |
1792 | ext4_orphan_del(NULL, inode); | |
1793 | } | |
bfc1af65 NP |
1794 | |
1795 | return ret ? ret : copied; | |
ac27a0ec | 1796 | } |
d2a17637 MC |
1797 | |
1798 | static int ext4_da_reserve_space(struct inode *inode, int nrblocks) | |
1799 | { | |
030ba6bc | 1800 | int retries = 0; |
60e58e0f MC |
1801 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
1802 | unsigned long md_needed, mdblocks, total = 0; | |
d2a17637 MC |
1803 | |
1804 | /* | |
1805 | * recalculate the amount of metadata blocks to reserve | |
1806 | * in order to allocate nrblocks | |
1807 | * worse case is one extent per block | |
1808 | */ | |
030ba6bc | 1809 | repeat: |
d2a17637 MC |
1810 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); |
1811 | total = EXT4_I(inode)->i_reserved_data_blocks + nrblocks; | |
1812 | mdblocks = ext4_calc_metadata_amount(inode, total); | |
1813 | BUG_ON(mdblocks < EXT4_I(inode)->i_reserved_meta_blocks); | |
1814 | ||
1815 | md_needed = mdblocks - EXT4_I(inode)->i_reserved_meta_blocks; | |
1816 | total = md_needed + nrblocks; | |
1817 | ||
60e58e0f MC |
1818 | /* |
1819 | * Make quota reservation here to prevent quota overflow | |
1820 | * later. Real quota accounting is done at pages writeout | |
1821 | * time. | |
1822 | */ | |
1823 | if (vfs_dq_reserve_block(inode, total)) { | |
1824 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
1825 | return -EDQUOT; | |
1826 | } | |
1827 | ||
a30d542a | 1828 | if (ext4_claim_free_blocks(sbi, total)) { |
d2a17637 | 1829 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
9f0ccfd8 | 1830 | vfs_dq_release_reservation_block(inode, total); |
030ba6bc AK |
1831 | if (ext4_should_retry_alloc(inode->i_sb, &retries)) { |
1832 | yield(); | |
1833 | goto repeat; | |
1834 | } | |
d2a17637 MC |
1835 | return -ENOSPC; |
1836 | } | |
d2a17637 MC |
1837 | EXT4_I(inode)->i_reserved_data_blocks += nrblocks; |
1838 | EXT4_I(inode)->i_reserved_meta_blocks = mdblocks; | |
1839 | ||
1840 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
1841 | return 0; /* success */ | |
1842 | } | |
1843 | ||
12219aea | 1844 | static void ext4_da_release_space(struct inode *inode, int to_free) |
d2a17637 MC |
1845 | { |
1846 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
1847 | int total, mdb, mdb_free, release; | |
1848 | ||
cd213226 MC |
1849 | if (!to_free) |
1850 | return; /* Nothing to release, exit */ | |
1851 | ||
d2a17637 | 1852 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); |
cd213226 MC |
1853 | |
1854 | if (!EXT4_I(inode)->i_reserved_data_blocks) { | |
1855 | /* | |
1856 | * if there is no reserved blocks, but we try to free some | |
1857 | * then the counter is messed up somewhere. | |
1858 | * but since this function is called from invalidate | |
1859 | * page, it's harmless to return without any action | |
1860 | */ | |
1861 | printk(KERN_INFO "ext4 delalloc try to release %d reserved " | |
1862 | "blocks for inode %lu, but there is no reserved " | |
1863 | "data blocks\n", to_free, inode->i_ino); | |
1864 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
1865 | return; | |
1866 | } | |
1867 | ||
d2a17637 | 1868 | /* recalculate the number of metablocks still need to be reserved */ |
12219aea | 1869 | total = EXT4_I(inode)->i_reserved_data_blocks - to_free; |
d2a17637 MC |
1870 | mdb = ext4_calc_metadata_amount(inode, total); |
1871 | ||
1872 | /* figure out how many metablocks to release */ | |
1873 | BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks); | |
1874 | mdb_free = EXT4_I(inode)->i_reserved_meta_blocks - mdb; | |
1875 | ||
d2a17637 MC |
1876 | release = to_free + mdb_free; |
1877 | ||
6bc6e63f AK |
1878 | /* update fs dirty blocks counter for truncate case */ |
1879 | percpu_counter_sub(&sbi->s_dirtyblocks_counter, release); | |
d2a17637 MC |
1880 | |
1881 | /* update per-inode reservations */ | |
12219aea AK |
1882 | BUG_ON(to_free > EXT4_I(inode)->i_reserved_data_blocks); |
1883 | EXT4_I(inode)->i_reserved_data_blocks -= to_free; | |
d2a17637 MC |
1884 | |
1885 | BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks); | |
1886 | EXT4_I(inode)->i_reserved_meta_blocks = mdb; | |
d2a17637 | 1887 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
60e58e0f MC |
1888 | |
1889 | vfs_dq_release_reservation_block(inode, release); | |
d2a17637 MC |
1890 | } |
1891 | ||
1892 | static void ext4_da_page_release_reservation(struct page *page, | |
de9a55b8 | 1893 | unsigned long offset) |
d2a17637 MC |
1894 | { |
1895 | int to_release = 0; | |
1896 | struct buffer_head *head, *bh; | |
1897 | unsigned int curr_off = 0; | |
1898 | ||
1899 | head = page_buffers(page); | |
1900 | bh = head; | |
1901 | do { | |
1902 | unsigned int next_off = curr_off + bh->b_size; | |
1903 | ||
1904 | if ((offset <= curr_off) && (buffer_delay(bh))) { | |
1905 | to_release++; | |
1906 | clear_buffer_delay(bh); | |
1907 | } | |
1908 | curr_off = next_off; | |
1909 | } while ((bh = bh->b_this_page) != head); | |
12219aea | 1910 | ext4_da_release_space(page->mapping->host, to_release); |
d2a17637 | 1911 | } |
ac27a0ec | 1912 | |
64769240 AT |
1913 | /* |
1914 | * Delayed allocation stuff | |
1915 | */ | |
1916 | ||
64769240 AT |
1917 | /* |
1918 | * mpage_da_submit_io - walks through extent of pages and try to write | |
a1d6cc56 | 1919 | * them with writepage() call back |
64769240 AT |
1920 | * |
1921 | * @mpd->inode: inode | |
1922 | * @mpd->first_page: first page of the extent | |
1923 | * @mpd->next_page: page after the last page of the extent | |
64769240 AT |
1924 | * |
1925 | * By the time mpage_da_submit_io() is called we expect all blocks | |
1926 | * to be allocated. this may be wrong if allocation failed. | |
1927 | * | |
1928 | * As pages are already locked by write_cache_pages(), we can't use it | |
1929 | */ | |
1930 | static int mpage_da_submit_io(struct mpage_da_data *mpd) | |
1931 | { | |
22208ded | 1932 | long pages_skipped; |
791b7f08 AK |
1933 | struct pagevec pvec; |
1934 | unsigned long index, end; | |
1935 | int ret = 0, err, nr_pages, i; | |
1936 | struct inode *inode = mpd->inode; | |
1937 | struct address_space *mapping = inode->i_mapping; | |
64769240 AT |
1938 | |
1939 | BUG_ON(mpd->next_page <= mpd->first_page); | |
791b7f08 AK |
1940 | /* |
1941 | * We need to start from the first_page to the next_page - 1 | |
1942 | * to make sure we also write the mapped dirty buffer_heads. | |
8dc207c0 | 1943 | * If we look at mpd->b_blocknr we would only be looking |
791b7f08 AK |
1944 | * at the currently mapped buffer_heads. |
1945 | */ | |
64769240 AT |
1946 | index = mpd->first_page; |
1947 | end = mpd->next_page - 1; | |
1948 | ||
791b7f08 | 1949 | pagevec_init(&pvec, 0); |
64769240 | 1950 | while (index <= end) { |
791b7f08 | 1951 | nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE); |
64769240 AT |
1952 | if (nr_pages == 0) |
1953 | break; | |
1954 | for (i = 0; i < nr_pages; i++) { | |
1955 | struct page *page = pvec.pages[i]; | |
1956 | ||
791b7f08 AK |
1957 | index = page->index; |
1958 | if (index > end) | |
1959 | break; | |
1960 | index++; | |
1961 | ||
1962 | BUG_ON(!PageLocked(page)); | |
1963 | BUG_ON(PageWriteback(page)); | |
1964 | ||
22208ded | 1965 | pages_skipped = mpd->wbc->pages_skipped; |
a1d6cc56 | 1966 | err = mapping->a_ops->writepage(page, mpd->wbc); |
22208ded AK |
1967 | if (!err && (pages_skipped == mpd->wbc->pages_skipped)) |
1968 | /* | |
1969 | * have successfully written the page | |
1970 | * without skipping the same | |
1971 | */ | |
a1d6cc56 | 1972 | mpd->pages_written++; |
64769240 AT |
1973 | /* |
1974 | * In error case, we have to continue because | |
1975 | * remaining pages are still locked | |
1976 | * XXX: unlock and re-dirty them? | |
1977 | */ | |
1978 | if (ret == 0) | |
1979 | ret = err; | |
1980 | } | |
1981 | pagevec_release(&pvec); | |
1982 | } | |
64769240 AT |
1983 | return ret; |
1984 | } | |
1985 | ||
1986 | /* | |
1987 | * mpage_put_bnr_to_bhs - walk blocks and assign them actual numbers | |
1988 | * | |
1989 | * @mpd->inode - inode to walk through | |
1990 | * @exbh->b_blocknr - first block on a disk | |
1991 | * @exbh->b_size - amount of space in bytes | |
1992 | * @logical - first logical block to start assignment with | |
1993 | * | |
1994 | * the function goes through all passed space and put actual disk | |
29fa89d0 | 1995 | * block numbers into buffer heads, dropping BH_Delay and BH_Unwritten |
64769240 AT |
1996 | */ |
1997 | static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd, sector_t logical, | |
1998 | struct buffer_head *exbh) | |
1999 | { | |
2000 | struct inode *inode = mpd->inode; | |
2001 | struct address_space *mapping = inode->i_mapping; | |
2002 | int blocks = exbh->b_size >> inode->i_blkbits; | |
2003 | sector_t pblock = exbh->b_blocknr, cur_logical; | |
2004 | struct buffer_head *head, *bh; | |
a1d6cc56 | 2005 | pgoff_t index, end; |
64769240 AT |
2006 | struct pagevec pvec; |
2007 | int nr_pages, i; | |
2008 | ||
2009 | index = logical >> (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2010 | end = (logical + blocks - 1) >> (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2011 | cur_logical = index << (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2012 | ||
2013 | pagevec_init(&pvec, 0); | |
2014 | ||
2015 | while (index <= end) { | |
2016 | /* XXX: optimize tail */ | |
2017 | nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE); | |
2018 | if (nr_pages == 0) | |
2019 | break; | |
2020 | for (i = 0; i < nr_pages; i++) { | |
2021 | struct page *page = pvec.pages[i]; | |
2022 | ||
2023 | index = page->index; | |
2024 | if (index > end) | |
2025 | break; | |
2026 | index++; | |
2027 | ||
2028 | BUG_ON(!PageLocked(page)); | |
2029 | BUG_ON(PageWriteback(page)); | |
2030 | BUG_ON(!page_has_buffers(page)); | |
2031 | ||
2032 | bh = page_buffers(page); | |
2033 | head = bh; | |
2034 | ||
2035 | /* skip blocks out of the range */ | |
2036 | do { | |
2037 | if (cur_logical >= logical) | |
2038 | break; | |
2039 | cur_logical++; | |
2040 | } while ((bh = bh->b_this_page) != head); | |
2041 | ||
2042 | do { | |
2043 | if (cur_logical >= logical + blocks) | |
2044 | break; | |
29fa89d0 AK |
2045 | |
2046 | if (buffer_delay(bh) || | |
2047 | buffer_unwritten(bh)) { | |
2048 | ||
2049 | BUG_ON(bh->b_bdev != inode->i_sb->s_bdev); | |
2050 | ||
2051 | if (buffer_delay(bh)) { | |
2052 | clear_buffer_delay(bh); | |
2053 | bh->b_blocknr = pblock; | |
2054 | } else { | |
2055 | /* | |
2056 | * unwritten already should have | |
2057 | * blocknr assigned. Verify that | |
2058 | */ | |
2059 | clear_buffer_unwritten(bh); | |
2060 | BUG_ON(bh->b_blocknr != pblock); | |
2061 | } | |
2062 | ||
61628a3f | 2063 | } else if (buffer_mapped(bh)) |
64769240 | 2064 | BUG_ON(bh->b_blocknr != pblock); |
64769240 AT |
2065 | |
2066 | cur_logical++; | |
2067 | pblock++; | |
2068 | } while ((bh = bh->b_this_page) != head); | |
2069 | } | |
2070 | pagevec_release(&pvec); | |
2071 | } | |
2072 | } | |
2073 | ||
2074 | ||
2075 | /* | |
2076 | * __unmap_underlying_blocks - just a helper function to unmap | |
2077 | * set of blocks described by @bh | |
2078 | */ | |
2079 | static inline void __unmap_underlying_blocks(struct inode *inode, | |
2080 | struct buffer_head *bh) | |
2081 | { | |
2082 | struct block_device *bdev = inode->i_sb->s_bdev; | |
2083 | int blocks, i; | |
2084 | ||
2085 | blocks = bh->b_size >> inode->i_blkbits; | |
2086 | for (i = 0; i < blocks; i++) | |
2087 | unmap_underlying_metadata(bdev, bh->b_blocknr + i); | |
2088 | } | |
2089 | ||
c4a0c46e AK |
2090 | static void ext4_da_block_invalidatepages(struct mpage_da_data *mpd, |
2091 | sector_t logical, long blk_cnt) | |
2092 | { | |
2093 | int nr_pages, i; | |
2094 | pgoff_t index, end; | |
2095 | struct pagevec pvec; | |
2096 | struct inode *inode = mpd->inode; | |
2097 | struct address_space *mapping = inode->i_mapping; | |
2098 | ||
2099 | index = logical >> (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2100 | end = (logical + blk_cnt - 1) >> | |
2101 | (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2102 | while (index <= end) { | |
2103 | nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE); | |
2104 | if (nr_pages == 0) | |
2105 | break; | |
2106 | for (i = 0; i < nr_pages; i++) { | |
2107 | struct page *page = pvec.pages[i]; | |
2108 | index = page->index; | |
2109 | if (index > end) | |
2110 | break; | |
2111 | index++; | |
2112 | ||
2113 | BUG_ON(!PageLocked(page)); | |
2114 | BUG_ON(PageWriteback(page)); | |
2115 | block_invalidatepage(page, 0); | |
2116 | ClearPageUptodate(page); | |
2117 | unlock_page(page); | |
2118 | } | |
2119 | } | |
2120 | return; | |
2121 | } | |
2122 | ||
df22291f AK |
2123 | static void ext4_print_free_blocks(struct inode *inode) |
2124 | { | |
2125 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
1693918e TT |
2126 | printk(KERN_CRIT "Total free blocks count %lld\n", |
2127 | ext4_count_free_blocks(inode->i_sb)); | |
2128 | printk(KERN_CRIT "Free/Dirty block details\n"); | |
2129 | printk(KERN_CRIT "free_blocks=%lld\n", | |
2130 | (long long) percpu_counter_sum(&sbi->s_freeblocks_counter)); | |
2131 | printk(KERN_CRIT "dirty_blocks=%lld\n", | |
2132 | (long long) percpu_counter_sum(&sbi->s_dirtyblocks_counter)); | |
2133 | printk(KERN_CRIT "Block reservation details\n"); | |
2134 | printk(KERN_CRIT "i_reserved_data_blocks=%u\n", | |
2135 | EXT4_I(inode)->i_reserved_data_blocks); | |
2136 | printk(KERN_CRIT "i_reserved_meta_blocks=%u\n", | |
2137 | EXT4_I(inode)->i_reserved_meta_blocks); | |
df22291f AK |
2138 | return; |
2139 | } | |
2140 | ||
64769240 AT |
2141 | /* |
2142 | * mpage_da_map_blocks - go through given space | |
2143 | * | |
8dc207c0 | 2144 | * @mpd - bh describing space |
64769240 AT |
2145 | * |
2146 | * The function skips space we know is already mapped to disk blocks. | |
2147 | * | |
64769240 | 2148 | */ |
ed5bde0b | 2149 | static int mpage_da_map_blocks(struct mpage_da_data *mpd) |
64769240 | 2150 | { |
2ac3b6e0 | 2151 | int err, blks, get_blocks_flags; |
030ba6bc | 2152 | struct buffer_head new; |
2fa3cdfb TT |
2153 | sector_t next = mpd->b_blocknr; |
2154 | unsigned max_blocks = mpd->b_size >> mpd->inode->i_blkbits; | |
2155 | loff_t disksize = EXT4_I(mpd->inode)->i_disksize; | |
2156 | handle_t *handle = NULL; | |
64769240 AT |
2157 | |
2158 | /* | |
2159 | * We consider only non-mapped and non-allocated blocks | |
2160 | */ | |
8dc207c0 | 2161 | if ((mpd->b_state & (1 << BH_Mapped)) && |
29fa89d0 AK |
2162 | !(mpd->b_state & (1 << BH_Delay)) && |
2163 | !(mpd->b_state & (1 << BH_Unwritten))) | |
c4a0c46e | 2164 | return 0; |
2fa3cdfb TT |
2165 | |
2166 | /* | |
2167 | * If we didn't accumulate anything to write simply return | |
2168 | */ | |
2169 | if (!mpd->b_size) | |
2170 | return 0; | |
2171 | ||
2172 | handle = ext4_journal_current_handle(); | |
2173 | BUG_ON(!handle); | |
2174 | ||
79ffab34 | 2175 | /* |
2ac3b6e0 TT |
2176 | * Call ext4_get_blocks() to allocate any delayed allocation |
2177 | * blocks, or to convert an uninitialized extent to be | |
2178 | * initialized (in the case where we have written into | |
2179 | * one or more preallocated blocks). | |
2180 | * | |
2181 | * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE to | |
2182 | * indicate that we are on the delayed allocation path. This | |
2183 | * affects functions in many different parts of the allocation | |
2184 | * call path. This flag exists primarily because we don't | |
2185 | * want to change *many* call functions, so ext4_get_blocks() | |
2186 | * will set the magic i_delalloc_reserved_flag once the | |
2187 | * inode's allocation semaphore is taken. | |
2188 | * | |
2189 | * If the blocks in questions were delalloc blocks, set | |
2190 | * EXT4_GET_BLOCKS_DELALLOC_RESERVE so the delalloc accounting | |
2191 | * variables are updated after the blocks have been allocated. | |
79ffab34 | 2192 | */ |
2ac3b6e0 TT |
2193 | new.b_state = 0; |
2194 | get_blocks_flags = (EXT4_GET_BLOCKS_CREATE | | |
2195 | EXT4_GET_BLOCKS_DELALLOC_RESERVE); | |
2196 | if (mpd->b_state & (1 << BH_Delay)) | |
2197 | get_blocks_flags |= EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE; | |
2fa3cdfb | 2198 | blks = ext4_get_blocks(handle, mpd->inode, next, max_blocks, |
2ac3b6e0 | 2199 | &new, get_blocks_flags); |
2fa3cdfb TT |
2200 | if (blks < 0) { |
2201 | err = blks; | |
ed5bde0b TT |
2202 | /* |
2203 | * If get block returns with error we simply | |
2204 | * return. Later writepage will redirty the page and | |
2205 | * writepages will find the dirty page again | |
c4a0c46e AK |
2206 | */ |
2207 | if (err == -EAGAIN) | |
2208 | return 0; | |
df22291f AK |
2209 | |
2210 | if (err == -ENOSPC && | |
ed5bde0b | 2211 | ext4_count_free_blocks(mpd->inode->i_sb)) { |
df22291f AK |
2212 | mpd->retval = err; |
2213 | return 0; | |
2214 | } | |
2215 | ||
c4a0c46e | 2216 | /* |
ed5bde0b TT |
2217 | * get block failure will cause us to loop in |
2218 | * writepages, because a_ops->writepage won't be able | |
2219 | * to make progress. The page will be redirtied by | |
2220 | * writepage and writepages will again try to write | |
2221 | * the same. | |
c4a0c46e | 2222 | */ |
1693918e TT |
2223 | ext4_msg(mpd->inode->i_sb, KERN_CRIT, |
2224 | "delayed block allocation failed for inode %lu at " | |
2225 | "logical offset %llu with max blocks %zd with " | |
2226 | "error %d\n", mpd->inode->i_ino, | |
2227 | (unsigned long long) next, | |
2228 | mpd->b_size >> mpd->inode->i_blkbits, err); | |
2229 | printk(KERN_CRIT "This should not happen!! " | |
2230 | "Data will be lost\n"); | |
030ba6bc | 2231 | if (err == -ENOSPC) { |
df22291f | 2232 | ext4_print_free_blocks(mpd->inode); |
030ba6bc | 2233 | } |
2fa3cdfb | 2234 | /* invalidate all the pages */ |
c4a0c46e | 2235 | ext4_da_block_invalidatepages(mpd, next, |
8dc207c0 | 2236 | mpd->b_size >> mpd->inode->i_blkbits); |
c4a0c46e AK |
2237 | return err; |
2238 | } | |
2fa3cdfb TT |
2239 | BUG_ON(blks == 0); |
2240 | ||
2241 | new.b_size = (blks << mpd->inode->i_blkbits); | |
64769240 | 2242 | |
a1d6cc56 AK |
2243 | if (buffer_new(&new)) |
2244 | __unmap_underlying_blocks(mpd->inode, &new); | |
64769240 | 2245 | |
a1d6cc56 AK |
2246 | /* |
2247 | * If blocks are delayed marked, we need to | |
2248 | * put actual blocknr and drop delayed bit | |
2249 | */ | |
8dc207c0 TT |
2250 | if ((mpd->b_state & (1 << BH_Delay)) || |
2251 | (mpd->b_state & (1 << BH_Unwritten))) | |
a1d6cc56 | 2252 | mpage_put_bnr_to_bhs(mpd, next, &new); |
64769240 | 2253 | |
2fa3cdfb TT |
2254 | if (ext4_should_order_data(mpd->inode)) { |
2255 | err = ext4_jbd2_file_inode(handle, mpd->inode); | |
2256 | if (err) | |
2257 | return err; | |
2258 | } | |
2259 | ||
2260 | /* | |
03f5d8bc | 2261 | * Update on-disk size along with block allocation. |
2fa3cdfb TT |
2262 | */ |
2263 | disksize = ((loff_t) next + blks) << mpd->inode->i_blkbits; | |
2264 | if (disksize > i_size_read(mpd->inode)) | |
2265 | disksize = i_size_read(mpd->inode); | |
2266 | if (disksize > EXT4_I(mpd->inode)->i_disksize) { | |
2267 | ext4_update_i_disksize(mpd->inode, disksize); | |
2268 | return ext4_mark_inode_dirty(handle, mpd->inode); | |
2269 | } | |
2270 | ||
c4a0c46e | 2271 | return 0; |
64769240 AT |
2272 | } |
2273 | ||
bf068ee2 AK |
2274 | #define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | \ |
2275 | (1 << BH_Delay) | (1 << BH_Unwritten)) | |
64769240 AT |
2276 | |
2277 | /* | |
2278 | * mpage_add_bh_to_extent - try to add one more block to extent of blocks | |
2279 | * | |
2280 | * @mpd->lbh - extent of blocks | |
2281 | * @logical - logical number of the block in the file | |
2282 | * @bh - bh of the block (used to access block's state) | |
2283 | * | |
2284 | * the function is used to collect contig. blocks in same state | |
2285 | */ | |
2286 | static void mpage_add_bh_to_extent(struct mpage_da_data *mpd, | |
8dc207c0 TT |
2287 | sector_t logical, size_t b_size, |
2288 | unsigned long b_state) | |
64769240 | 2289 | { |
64769240 | 2290 | sector_t next; |
8dc207c0 | 2291 | int nrblocks = mpd->b_size >> mpd->inode->i_blkbits; |
64769240 | 2292 | |
525f4ed8 MC |
2293 | /* check if thereserved journal credits might overflow */ |
2294 | if (!(EXT4_I(mpd->inode)->i_flags & EXT4_EXTENTS_FL)) { | |
2295 | if (nrblocks >= EXT4_MAX_TRANS_DATA) { | |
2296 | /* | |
2297 | * With non-extent format we are limited by the journal | |
2298 | * credit available. Total credit needed to insert | |
2299 | * nrblocks contiguous blocks is dependent on the | |
2300 | * nrblocks. So limit nrblocks. | |
2301 | */ | |
2302 | goto flush_it; | |
2303 | } else if ((nrblocks + (b_size >> mpd->inode->i_blkbits)) > | |
2304 | EXT4_MAX_TRANS_DATA) { | |
2305 | /* | |
2306 | * Adding the new buffer_head would make it cross the | |
2307 | * allowed limit for which we have journal credit | |
2308 | * reserved. So limit the new bh->b_size | |
2309 | */ | |
2310 | b_size = (EXT4_MAX_TRANS_DATA - nrblocks) << | |
2311 | mpd->inode->i_blkbits; | |
2312 | /* we will do mpage_da_submit_io in the next loop */ | |
2313 | } | |
2314 | } | |
64769240 AT |
2315 | /* |
2316 | * First block in the extent | |
2317 | */ | |
8dc207c0 TT |
2318 | if (mpd->b_size == 0) { |
2319 | mpd->b_blocknr = logical; | |
2320 | mpd->b_size = b_size; | |
2321 | mpd->b_state = b_state & BH_FLAGS; | |
64769240 AT |
2322 | return; |
2323 | } | |
2324 | ||
8dc207c0 | 2325 | next = mpd->b_blocknr + nrblocks; |
64769240 AT |
2326 | /* |
2327 | * Can we merge the block to our big extent? | |
2328 | */ | |
8dc207c0 TT |
2329 | if (logical == next && (b_state & BH_FLAGS) == mpd->b_state) { |
2330 | mpd->b_size += b_size; | |
64769240 AT |
2331 | return; |
2332 | } | |
2333 | ||
525f4ed8 | 2334 | flush_it: |
64769240 AT |
2335 | /* |
2336 | * We couldn't merge the block to our extent, so we | |
2337 | * need to flush current extent and start new one | |
2338 | */ | |
c4a0c46e AK |
2339 | if (mpage_da_map_blocks(mpd) == 0) |
2340 | mpage_da_submit_io(mpd); | |
a1d6cc56 AK |
2341 | mpd->io_done = 1; |
2342 | return; | |
64769240 AT |
2343 | } |
2344 | ||
c364b22c | 2345 | static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh) |
29fa89d0 | 2346 | { |
c364b22c | 2347 | return (buffer_delay(bh) || buffer_unwritten(bh)) && buffer_dirty(bh); |
29fa89d0 AK |
2348 | } |
2349 | ||
64769240 AT |
2350 | /* |
2351 | * __mpage_da_writepage - finds extent of pages and blocks | |
2352 | * | |
2353 | * @page: page to consider | |
2354 | * @wbc: not used, we just follow rules | |
2355 | * @data: context | |
2356 | * | |
2357 | * The function finds extents of pages and scan them for all blocks. | |
2358 | */ | |
2359 | static int __mpage_da_writepage(struct page *page, | |
2360 | struct writeback_control *wbc, void *data) | |
2361 | { | |
2362 | struct mpage_da_data *mpd = data; | |
2363 | struct inode *inode = mpd->inode; | |
8dc207c0 | 2364 | struct buffer_head *bh, *head; |
64769240 AT |
2365 | sector_t logical; |
2366 | ||
a1d6cc56 AK |
2367 | if (mpd->io_done) { |
2368 | /* | |
2369 | * Rest of the page in the page_vec | |
2370 | * redirty then and skip then. We will | |
fd589a8f | 2371 | * try to write them again after |
a1d6cc56 AK |
2372 | * starting a new transaction |
2373 | */ | |
2374 | redirty_page_for_writepage(wbc, page); | |
2375 | unlock_page(page); | |
2376 | return MPAGE_DA_EXTENT_TAIL; | |
2377 | } | |
64769240 AT |
2378 | /* |
2379 | * Can we merge this page to current extent? | |
2380 | */ | |
2381 | if (mpd->next_page != page->index) { | |
2382 | /* | |
2383 | * Nope, we can't. So, we map non-allocated blocks | |
a1d6cc56 | 2384 | * and start IO on them using writepage() |
64769240 AT |
2385 | */ |
2386 | if (mpd->next_page != mpd->first_page) { | |
c4a0c46e AK |
2387 | if (mpage_da_map_blocks(mpd) == 0) |
2388 | mpage_da_submit_io(mpd); | |
a1d6cc56 AK |
2389 | /* |
2390 | * skip rest of the page in the page_vec | |
2391 | */ | |
2392 | mpd->io_done = 1; | |
2393 | redirty_page_for_writepage(wbc, page); | |
2394 | unlock_page(page); | |
2395 | return MPAGE_DA_EXTENT_TAIL; | |
64769240 AT |
2396 | } |
2397 | ||
2398 | /* | |
2399 | * Start next extent of pages ... | |
2400 | */ | |
2401 | mpd->first_page = page->index; | |
2402 | ||
2403 | /* | |
2404 | * ... and blocks | |
2405 | */ | |
8dc207c0 TT |
2406 | mpd->b_size = 0; |
2407 | mpd->b_state = 0; | |
2408 | mpd->b_blocknr = 0; | |
64769240 AT |
2409 | } |
2410 | ||
2411 | mpd->next_page = page->index + 1; | |
2412 | logical = (sector_t) page->index << | |
2413 | (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2414 | ||
2415 | if (!page_has_buffers(page)) { | |
8dc207c0 TT |
2416 | mpage_add_bh_to_extent(mpd, logical, PAGE_CACHE_SIZE, |
2417 | (1 << BH_Dirty) | (1 << BH_Uptodate)); | |
a1d6cc56 AK |
2418 | if (mpd->io_done) |
2419 | return MPAGE_DA_EXTENT_TAIL; | |
64769240 AT |
2420 | } else { |
2421 | /* | |
2422 | * Page with regular buffer heads, just add all dirty ones | |
2423 | */ | |
2424 | head = page_buffers(page); | |
2425 | bh = head; | |
2426 | do { | |
2427 | BUG_ON(buffer_locked(bh)); | |
791b7f08 AK |
2428 | /* |
2429 | * We need to try to allocate | |
2430 | * unmapped blocks in the same page. | |
2431 | * Otherwise we won't make progress | |
43ce1d23 | 2432 | * with the page in ext4_writepage |
791b7f08 | 2433 | */ |
c364b22c | 2434 | if (ext4_bh_delay_or_unwritten(NULL, bh)) { |
8dc207c0 TT |
2435 | mpage_add_bh_to_extent(mpd, logical, |
2436 | bh->b_size, | |
2437 | bh->b_state); | |
a1d6cc56 AK |
2438 | if (mpd->io_done) |
2439 | return MPAGE_DA_EXTENT_TAIL; | |
791b7f08 AK |
2440 | } else if (buffer_dirty(bh) && (buffer_mapped(bh))) { |
2441 | /* | |
2442 | * mapped dirty buffer. We need to update | |
2443 | * the b_state because we look at | |
2444 | * b_state in mpage_da_map_blocks. We don't | |
2445 | * update b_size because if we find an | |
2446 | * unmapped buffer_head later we need to | |
2447 | * use the b_state flag of that buffer_head. | |
2448 | */ | |
8dc207c0 TT |
2449 | if (mpd->b_size == 0) |
2450 | mpd->b_state = bh->b_state & BH_FLAGS; | |
a1d6cc56 | 2451 | } |
64769240 AT |
2452 | logical++; |
2453 | } while ((bh = bh->b_this_page) != head); | |
2454 | } | |
2455 | ||
2456 | return 0; | |
2457 | } | |
2458 | ||
64769240 | 2459 | /* |
b920c755 TT |
2460 | * This is a special get_blocks_t callback which is used by |
2461 | * ext4_da_write_begin(). It will either return mapped block or | |
2462 | * reserve space for a single block. | |
29fa89d0 AK |
2463 | * |
2464 | * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set. | |
2465 | * We also have b_blocknr = -1 and b_bdev initialized properly | |
2466 | * | |
2467 | * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set. | |
2468 | * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev | |
2469 | * initialized properly. | |
64769240 AT |
2470 | */ |
2471 | static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock, | |
2472 | struct buffer_head *bh_result, int create) | |
2473 | { | |
2474 | int ret = 0; | |
33b9817e AK |
2475 | sector_t invalid_block = ~((sector_t) 0xffff); |
2476 | ||
2477 | if (invalid_block < ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es)) | |
2478 | invalid_block = ~0; | |
64769240 AT |
2479 | |
2480 | BUG_ON(create == 0); | |
2481 | BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize); | |
2482 | ||
2483 | /* | |
2484 | * first, we need to know whether the block is allocated already | |
2485 | * preallocated blocks are unmapped but should treated | |
2486 | * the same as allocated blocks. | |
2487 | */ | |
c2177057 | 2488 | ret = ext4_get_blocks(NULL, inode, iblock, 1, bh_result, 0); |
d2a17637 MC |
2489 | if ((ret == 0) && !buffer_delay(bh_result)) { |
2490 | /* the block isn't (pre)allocated yet, let's reserve space */ | |
64769240 AT |
2491 | /* |
2492 | * XXX: __block_prepare_write() unmaps passed block, | |
2493 | * is it OK? | |
2494 | */ | |
d2a17637 MC |
2495 | ret = ext4_da_reserve_space(inode, 1); |
2496 | if (ret) | |
2497 | /* not enough space to reserve */ | |
2498 | return ret; | |
2499 | ||
33b9817e | 2500 | map_bh(bh_result, inode->i_sb, invalid_block); |
64769240 AT |
2501 | set_buffer_new(bh_result); |
2502 | set_buffer_delay(bh_result); | |
2503 | } else if (ret > 0) { | |
2504 | bh_result->b_size = (ret << inode->i_blkbits); | |
29fa89d0 AK |
2505 | if (buffer_unwritten(bh_result)) { |
2506 | /* A delayed write to unwritten bh should | |
2507 | * be marked new and mapped. Mapped ensures | |
2508 | * that we don't do get_block multiple times | |
2509 | * when we write to the same offset and new | |
2510 | * ensures that we do proper zero out for | |
2511 | * partial write. | |
2512 | */ | |
9c1ee184 | 2513 | set_buffer_new(bh_result); |
29fa89d0 AK |
2514 | set_buffer_mapped(bh_result); |
2515 | } | |
64769240 AT |
2516 | ret = 0; |
2517 | } | |
2518 | ||
2519 | return ret; | |
2520 | } | |
61628a3f | 2521 | |
b920c755 TT |
2522 | /* |
2523 | * This function is used as a standard get_block_t calback function | |
2524 | * when there is no desire to allocate any blocks. It is used as a | |
2525 | * callback function for block_prepare_write(), nobh_writepage(), and | |
2526 | * block_write_full_page(). These functions should only try to map a | |
2527 | * single block at a time. | |
2528 | * | |
2529 | * Since this function doesn't do block allocations even if the caller | |
2530 | * requests it by passing in create=1, it is critically important that | |
2531 | * any caller checks to make sure that any buffer heads are returned | |
2532 | * by this function are either all already mapped or marked for | |
2533 | * delayed allocation before calling nobh_writepage() or | |
2534 | * block_write_full_page(). Otherwise, b_blocknr could be left | |
2535 | * unitialized, and the page write functions will be taken by | |
2536 | * surprise. | |
2537 | */ | |
2538 | static int noalloc_get_block_write(struct inode *inode, sector_t iblock, | |
f0e6c985 AK |
2539 | struct buffer_head *bh_result, int create) |
2540 | { | |
2541 | int ret = 0; | |
2542 | unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; | |
2543 | ||
a2dc52b5 TT |
2544 | BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize); |
2545 | ||
f0e6c985 AK |
2546 | /* |
2547 | * we don't want to do block allocation in writepage | |
2548 | * so call get_block_wrap with create = 0 | |
2549 | */ | |
c2177057 | 2550 | ret = ext4_get_blocks(NULL, inode, iblock, max_blocks, bh_result, 0); |
f0e6c985 AK |
2551 | if (ret > 0) { |
2552 | bh_result->b_size = (ret << inode->i_blkbits); | |
2553 | ret = 0; | |
2554 | } | |
2555 | return ret; | |
61628a3f MC |
2556 | } |
2557 | ||
62e086be AK |
2558 | static int bget_one(handle_t *handle, struct buffer_head *bh) |
2559 | { | |
2560 | get_bh(bh); | |
2561 | return 0; | |
2562 | } | |
2563 | ||
2564 | static int bput_one(handle_t *handle, struct buffer_head *bh) | |
2565 | { | |
2566 | put_bh(bh); | |
2567 | return 0; | |
2568 | } | |
2569 | ||
2570 | static int __ext4_journalled_writepage(struct page *page, | |
62e086be AK |
2571 | unsigned int len) |
2572 | { | |
2573 | struct address_space *mapping = page->mapping; | |
2574 | struct inode *inode = mapping->host; | |
2575 | struct buffer_head *page_bufs; | |
2576 | handle_t *handle = NULL; | |
2577 | int ret = 0; | |
2578 | int err; | |
2579 | ||
2580 | page_bufs = page_buffers(page); | |
2581 | BUG_ON(!page_bufs); | |
2582 | walk_page_buffers(handle, page_bufs, 0, len, NULL, bget_one); | |
2583 | /* As soon as we unlock the page, it can go away, but we have | |
2584 | * references to buffers so we are safe */ | |
2585 | unlock_page(page); | |
2586 | ||
2587 | handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode)); | |
2588 | if (IS_ERR(handle)) { | |
2589 | ret = PTR_ERR(handle); | |
2590 | goto out; | |
2591 | } | |
2592 | ||
2593 | ret = walk_page_buffers(handle, page_bufs, 0, len, NULL, | |
2594 | do_journal_get_write_access); | |
2595 | ||
2596 | err = walk_page_buffers(handle, page_bufs, 0, len, NULL, | |
2597 | write_end_fn); | |
2598 | if (ret == 0) | |
2599 | ret = err; | |
2600 | err = ext4_journal_stop(handle); | |
2601 | if (!ret) | |
2602 | ret = err; | |
2603 | ||
2604 | walk_page_buffers(handle, page_bufs, 0, len, NULL, bput_one); | |
2605 | EXT4_I(inode)->i_state |= EXT4_STATE_JDATA; | |
2606 | out: | |
2607 | return ret; | |
2608 | } | |
2609 | ||
61628a3f | 2610 | /* |
43ce1d23 AK |
2611 | * Note that we don't need to start a transaction unless we're journaling data |
2612 | * because we should have holes filled from ext4_page_mkwrite(). We even don't | |
2613 | * need to file the inode to the transaction's list in ordered mode because if | |
2614 | * we are writing back data added by write(), the inode is already there and if | |
2615 | * we are writing back data modified via mmap(), noone guarantees in which | |
2616 | * transaction the data will hit the disk. In case we are journaling data, we | |
2617 | * cannot start transaction directly because transaction start ranks above page | |
2618 | * lock so we have to do some magic. | |
2619 | * | |
b920c755 TT |
2620 | * This function can get called via... |
2621 | * - ext4_da_writepages after taking page lock (have journal handle) | |
2622 | * - journal_submit_inode_data_buffers (no journal handle) | |
2623 | * - shrink_page_list via pdflush (no journal handle) | |
2624 | * - grab_page_cache when doing write_begin (have journal handle) | |
43ce1d23 AK |
2625 | * |
2626 | * We don't do any block allocation in this function. If we have page with | |
2627 | * multiple blocks we need to write those buffer_heads that are mapped. This | |
2628 | * is important for mmaped based write. So if we do with blocksize 1K | |
2629 | * truncate(f, 1024); | |
2630 | * a = mmap(f, 0, 4096); | |
2631 | * a[0] = 'a'; | |
2632 | * truncate(f, 4096); | |
2633 | * we have in the page first buffer_head mapped via page_mkwrite call back | |
2634 | * but other bufer_heads would be unmapped but dirty(dirty done via the | |
2635 | * do_wp_page). So writepage should write the first block. If we modify | |
2636 | * the mmap area beyond 1024 we will again get a page_fault and the | |
2637 | * page_mkwrite callback will do the block allocation and mark the | |
2638 | * buffer_heads mapped. | |
2639 | * | |
2640 | * We redirty the page if we have any buffer_heads that is either delay or | |
2641 | * unwritten in the page. | |
2642 | * | |
2643 | * We can get recursively called as show below. | |
2644 | * | |
2645 | * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() -> | |
2646 | * ext4_writepage() | |
2647 | * | |
2648 | * But since we don't do any block allocation we should not deadlock. | |
2649 | * Page also have the dirty flag cleared so we don't get recurive page_lock. | |
61628a3f | 2650 | */ |
43ce1d23 | 2651 | static int ext4_writepage(struct page *page, |
62e086be | 2652 | struct writeback_control *wbc) |
64769240 | 2653 | { |
64769240 | 2654 | int ret = 0; |
61628a3f | 2655 | loff_t size; |
498e5f24 | 2656 | unsigned int len; |
61628a3f MC |
2657 | struct buffer_head *page_bufs; |
2658 | struct inode *inode = page->mapping->host; | |
2659 | ||
43ce1d23 | 2660 | trace_ext4_writepage(inode, page); |
f0e6c985 AK |
2661 | size = i_size_read(inode); |
2662 | if (page->index == size >> PAGE_CACHE_SHIFT) | |
2663 | len = size & ~PAGE_CACHE_MASK; | |
2664 | else | |
2665 | len = PAGE_CACHE_SIZE; | |
64769240 | 2666 | |
f0e6c985 | 2667 | if (page_has_buffers(page)) { |
61628a3f | 2668 | page_bufs = page_buffers(page); |
f0e6c985 | 2669 | if (walk_page_buffers(NULL, page_bufs, 0, len, NULL, |
c364b22c | 2670 | ext4_bh_delay_or_unwritten)) { |
61628a3f | 2671 | /* |
f0e6c985 AK |
2672 | * We don't want to do block allocation |
2673 | * So redirty the page and return | |
cd1aac32 AK |
2674 | * We may reach here when we do a journal commit |
2675 | * via journal_submit_inode_data_buffers. | |
2676 | * If we don't have mapping block we just ignore | |
f0e6c985 AK |
2677 | * them. We can also reach here via shrink_page_list |
2678 | */ | |
2679 | redirty_page_for_writepage(wbc, page); | |
2680 | unlock_page(page); | |
2681 | return 0; | |
2682 | } | |
2683 | } else { | |
2684 | /* | |
2685 | * The test for page_has_buffers() is subtle: | |
2686 | * We know the page is dirty but it lost buffers. That means | |
2687 | * that at some moment in time after write_begin()/write_end() | |
2688 | * has been called all buffers have been clean and thus they | |
2689 | * must have been written at least once. So they are all | |
2690 | * mapped and we can happily proceed with mapping them | |
2691 | * and writing the page. | |
2692 | * | |
2693 | * Try to initialize the buffer_heads and check whether | |
2694 | * all are mapped and non delay. We don't want to | |
2695 | * do block allocation here. | |
2696 | */ | |
b767e78a | 2697 | ret = block_prepare_write(page, 0, len, |
b920c755 | 2698 | noalloc_get_block_write); |
f0e6c985 AK |
2699 | if (!ret) { |
2700 | page_bufs = page_buffers(page); | |
2701 | /* check whether all are mapped and non delay */ | |
2702 | if (walk_page_buffers(NULL, page_bufs, 0, len, NULL, | |
c364b22c | 2703 | ext4_bh_delay_or_unwritten)) { |
f0e6c985 AK |
2704 | redirty_page_for_writepage(wbc, page); |
2705 | unlock_page(page); | |
2706 | return 0; | |
2707 | } | |
2708 | } else { | |
2709 | /* | |
2710 | * We can't do block allocation here | |
2711 | * so just redity the page and unlock | |
2712 | * and return | |
61628a3f | 2713 | */ |
61628a3f MC |
2714 | redirty_page_for_writepage(wbc, page); |
2715 | unlock_page(page); | |
2716 | return 0; | |
2717 | } | |
ed9b3e33 | 2718 | /* now mark the buffer_heads as dirty and uptodate */ |
b767e78a | 2719 | block_commit_write(page, 0, len); |
64769240 AT |
2720 | } |
2721 | ||
43ce1d23 AK |
2722 | if (PageChecked(page) && ext4_should_journal_data(inode)) { |
2723 | /* | |
2724 | * It's mmapped pagecache. Add buffers and journal it. There | |
2725 | * doesn't seem much point in redirtying the page here. | |
2726 | */ | |
2727 | ClearPageChecked(page); | |
3f0ca309 | 2728 | return __ext4_journalled_writepage(page, len); |
43ce1d23 AK |
2729 | } |
2730 | ||
64769240 | 2731 | if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode)) |
b920c755 | 2732 | ret = nobh_writepage(page, noalloc_get_block_write, wbc); |
64769240 | 2733 | else |
b920c755 TT |
2734 | ret = block_write_full_page(page, noalloc_get_block_write, |
2735 | wbc); | |
64769240 | 2736 | |
64769240 AT |
2737 | return ret; |
2738 | } | |
2739 | ||
61628a3f | 2740 | /* |
525f4ed8 MC |
2741 | * This is called via ext4_da_writepages() to |
2742 | * calulate the total number of credits to reserve to fit | |
2743 | * a single extent allocation into a single transaction, | |
2744 | * ext4_da_writpeages() will loop calling this before | |
2745 | * the block allocation. | |
61628a3f | 2746 | */ |
525f4ed8 MC |
2747 | |
2748 | static int ext4_da_writepages_trans_blocks(struct inode *inode) | |
2749 | { | |
2750 | int max_blocks = EXT4_I(inode)->i_reserved_data_blocks; | |
2751 | ||
2752 | /* | |
2753 | * With non-extent format the journal credit needed to | |
2754 | * insert nrblocks contiguous block is dependent on | |
2755 | * number of contiguous block. So we will limit | |
2756 | * number of contiguous block to a sane value | |
2757 | */ | |
30c6e07a | 2758 | if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) && |
525f4ed8 MC |
2759 | (max_blocks > EXT4_MAX_TRANS_DATA)) |
2760 | max_blocks = EXT4_MAX_TRANS_DATA; | |
2761 | ||
2762 | return ext4_chunk_trans_blocks(inode, max_blocks); | |
2763 | } | |
61628a3f | 2764 | |
64769240 | 2765 | static int ext4_da_writepages(struct address_space *mapping, |
a1d6cc56 | 2766 | struct writeback_control *wbc) |
64769240 | 2767 | { |
22208ded AK |
2768 | pgoff_t index; |
2769 | int range_whole = 0; | |
61628a3f | 2770 | handle_t *handle = NULL; |
df22291f | 2771 | struct mpage_da_data mpd; |
5e745b04 | 2772 | struct inode *inode = mapping->host; |
22208ded | 2773 | int no_nrwrite_index_update; |
498e5f24 TT |
2774 | int pages_written = 0; |
2775 | long pages_skipped; | |
55138e0b | 2776 | unsigned int max_pages; |
2acf2c26 | 2777 | int range_cyclic, cycled = 1, io_done = 0; |
55138e0b TT |
2778 | int needed_blocks, ret = 0; |
2779 | long desired_nr_to_write, nr_to_writebump = 0; | |
de89de6e | 2780 | loff_t range_start = wbc->range_start; |
5e745b04 | 2781 | struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb); |
61628a3f | 2782 | |
9bffad1e | 2783 | trace_ext4_da_writepages(inode, wbc); |
ba80b101 | 2784 | |
61628a3f MC |
2785 | /* |
2786 | * No pages to write? This is mainly a kludge to avoid starting | |
2787 | * a transaction for special inodes like journal inode on last iput() | |
2788 | * because that could violate lock ordering on umount | |
2789 | */ | |
a1d6cc56 | 2790 | if (!mapping->nrpages || !mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) |
61628a3f | 2791 | return 0; |
2a21e37e TT |
2792 | |
2793 | /* | |
2794 | * If the filesystem has aborted, it is read-only, so return | |
2795 | * right away instead of dumping stack traces later on that | |
2796 | * will obscure the real source of the problem. We test | |
4ab2f15b | 2797 | * EXT4_MF_FS_ABORTED instead of sb->s_flag's MS_RDONLY because |
2a21e37e TT |
2798 | * the latter could be true if the filesystem is mounted |
2799 | * read-only, and in that case, ext4_da_writepages should | |
2800 | * *never* be called, so if that ever happens, we would want | |
2801 | * the stack trace. | |
2802 | */ | |
4ab2f15b | 2803 | if (unlikely(sbi->s_mount_flags & EXT4_MF_FS_ABORTED)) |
2a21e37e TT |
2804 | return -EROFS; |
2805 | ||
22208ded AK |
2806 | if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) |
2807 | range_whole = 1; | |
61628a3f | 2808 | |
2acf2c26 AK |
2809 | range_cyclic = wbc->range_cyclic; |
2810 | if (wbc->range_cyclic) { | |
22208ded | 2811 | index = mapping->writeback_index; |
2acf2c26 AK |
2812 | if (index) |
2813 | cycled = 0; | |
2814 | wbc->range_start = index << PAGE_CACHE_SHIFT; | |
2815 | wbc->range_end = LLONG_MAX; | |
2816 | wbc->range_cyclic = 0; | |
2817 | } else | |
22208ded | 2818 | index = wbc->range_start >> PAGE_CACHE_SHIFT; |
a1d6cc56 | 2819 | |
55138e0b TT |
2820 | /* |
2821 | * This works around two forms of stupidity. The first is in | |
2822 | * the writeback code, which caps the maximum number of pages | |
2823 | * written to be 1024 pages. This is wrong on multiple | |
2824 | * levels; different architectues have a different page size, | |
2825 | * which changes the maximum amount of data which gets | |
2826 | * written. Secondly, 4 megabytes is way too small. XFS | |
2827 | * forces this value to be 16 megabytes by multiplying | |
2828 | * nr_to_write parameter by four, and then relies on its | |
2829 | * allocator to allocate larger extents to make them | |
2830 | * contiguous. Unfortunately this brings us to the second | |
2831 | * stupidity, which is that ext4's mballoc code only allocates | |
2832 | * at most 2048 blocks. So we force contiguous writes up to | |
2833 | * the number of dirty blocks in the inode, or | |
2834 | * sbi->max_writeback_mb_bump whichever is smaller. | |
2835 | */ | |
2836 | max_pages = sbi->s_max_writeback_mb_bump << (20 - PAGE_CACHE_SHIFT); | |
2837 | if (!range_cyclic && range_whole) | |
2838 | desired_nr_to_write = wbc->nr_to_write * 8; | |
2839 | else | |
2840 | desired_nr_to_write = ext4_num_dirty_pages(inode, index, | |
2841 | max_pages); | |
2842 | if (desired_nr_to_write > max_pages) | |
2843 | desired_nr_to_write = max_pages; | |
2844 | ||
2845 | if (wbc->nr_to_write < desired_nr_to_write) { | |
2846 | nr_to_writebump = desired_nr_to_write - wbc->nr_to_write; | |
2847 | wbc->nr_to_write = desired_nr_to_write; | |
2848 | } | |
2849 | ||
df22291f AK |
2850 | mpd.wbc = wbc; |
2851 | mpd.inode = mapping->host; | |
2852 | ||
22208ded AK |
2853 | /* |
2854 | * we don't want write_cache_pages to update | |
2855 | * nr_to_write and writeback_index | |
2856 | */ | |
2857 | no_nrwrite_index_update = wbc->no_nrwrite_index_update; | |
2858 | wbc->no_nrwrite_index_update = 1; | |
2859 | pages_skipped = wbc->pages_skipped; | |
2860 | ||
2acf2c26 | 2861 | retry: |
22208ded | 2862 | while (!ret && wbc->nr_to_write > 0) { |
a1d6cc56 AK |
2863 | |
2864 | /* | |
2865 | * we insert one extent at a time. So we need | |
2866 | * credit needed for single extent allocation. | |
2867 | * journalled mode is currently not supported | |
2868 | * by delalloc | |
2869 | */ | |
2870 | BUG_ON(ext4_should_journal_data(inode)); | |
525f4ed8 | 2871 | needed_blocks = ext4_da_writepages_trans_blocks(inode); |
a1d6cc56 | 2872 | |
61628a3f MC |
2873 | /* start a new transaction*/ |
2874 | handle = ext4_journal_start(inode, needed_blocks); | |
2875 | if (IS_ERR(handle)) { | |
2876 | ret = PTR_ERR(handle); | |
1693918e | 2877 | ext4_msg(inode->i_sb, KERN_CRIT, "%s: jbd2_start: " |
a1d6cc56 AK |
2878 | "%ld pages, ino %lu; err %d\n", __func__, |
2879 | wbc->nr_to_write, inode->i_ino, ret); | |
61628a3f MC |
2880 | goto out_writepages; |
2881 | } | |
f63e6005 TT |
2882 | |
2883 | /* | |
2884 | * Now call __mpage_da_writepage to find the next | |
2885 | * contiguous region of logical blocks that need | |
2886 | * blocks to be allocated by ext4. We don't actually | |
2887 | * submit the blocks for I/O here, even though | |
2888 | * write_cache_pages thinks it will, and will set the | |
2889 | * pages as clean for write before calling | |
2890 | * __mpage_da_writepage(). | |
2891 | */ | |
2892 | mpd.b_size = 0; | |
2893 | mpd.b_state = 0; | |
2894 | mpd.b_blocknr = 0; | |
2895 | mpd.first_page = 0; | |
2896 | mpd.next_page = 0; | |
2897 | mpd.io_done = 0; | |
2898 | mpd.pages_written = 0; | |
2899 | mpd.retval = 0; | |
2900 | ret = write_cache_pages(mapping, wbc, __mpage_da_writepage, | |
2901 | &mpd); | |
2902 | /* | |
2903 | * If we have a contigous extent of pages and we | |
2904 | * haven't done the I/O yet, map the blocks and submit | |
2905 | * them for I/O. | |
2906 | */ | |
2907 | if (!mpd.io_done && mpd.next_page != mpd.first_page) { | |
2908 | if (mpage_da_map_blocks(&mpd) == 0) | |
2909 | mpage_da_submit_io(&mpd); | |
2910 | mpd.io_done = 1; | |
2911 | ret = MPAGE_DA_EXTENT_TAIL; | |
2912 | } | |
b3a3ca8c | 2913 | trace_ext4_da_write_pages(inode, &mpd); |
f63e6005 | 2914 | wbc->nr_to_write -= mpd.pages_written; |
df22291f | 2915 | |
61628a3f | 2916 | ext4_journal_stop(handle); |
df22291f | 2917 | |
8f64b32e | 2918 | if ((mpd.retval == -ENOSPC) && sbi->s_journal) { |
22208ded AK |
2919 | /* commit the transaction which would |
2920 | * free blocks released in the transaction | |
2921 | * and try again | |
2922 | */ | |
df22291f | 2923 | jbd2_journal_force_commit_nested(sbi->s_journal); |
22208ded AK |
2924 | wbc->pages_skipped = pages_skipped; |
2925 | ret = 0; | |
2926 | } else if (ret == MPAGE_DA_EXTENT_TAIL) { | |
a1d6cc56 AK |
2927 | /* |
2928 | * got one extent now try with | |
2929 | * rest of the pages | |
2930 | */ | |
22208ded AK |
2931 | pages_written += mpd.pages_written; |
2932 | wbc->pages_skipped = pages_skipped; | |
a1d6cc56 | 2933 | ret = 0; |
2acf2c26 | 2934 | io_done = 1; |
22208ded | 2935 | } else if (wbc->nr_to_write) |
61628a3f MC |
2936 | /* |
2937 | * There is no more writeout needed | |
2938 | * or we requested for a noblocking writeout | |
2939 | * and we found the device congested | |
2940 | */ | |
61628a3f | 2941 | break; |
a1d6cc56 | 2942 | } |
2acf2c26 AK |
2943 | if (!io_done && !cycled) { |
2944 | cycled = 1; | |
2945 | index = 0; | |
2946 | wbc->range_start = index << PAGE_CACHE_SHIFT; | |
2947 | wbc->range_end = mapping->writeback_index - 1; | |
2948 | goto retry; | |
2949 | } | |
22208ded | 2950 | if (pages_skipped != wbc->pages_skipped) |
1693918e TT |
2951 | ext4_msg(inode->i_sb, KERN_CRIT, |
2952 | "This should not happen leaving %s " | |
2953 | "with nr_to_write = %ld ret = %d\n", | |
2954 | __func__, wbc->nr_to_write, ret); | |
22208ded AK |
2955 | |
2956 | /* Update index */ | |
2957 | index += pages_written; | |
2acf2c26 | 2958 | wbc->range_cyclic = range_cyclic; |
22208ded AK |
2959 | if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) |
2960 | /* | |
2961 | * set the writeback_index so that range_cyclic | |
2962 | * mode will write it back later | |
2963 | */ | |
2964 | mapping->writeback_index = index; | |
a1d6cc56 | 2965 | |
61628a3f | 2966 | out_writepages: |
22208ded AK |
2967 | if (!no_nrwrite_index_update) |
2968 | wbc->no_nrwrite_index_update = 0; | |
55138e0b TT |
2969 | if (wbc->nr_to_write > nr_to_writebump) |
2970 | wbc->nr_to_write -= nr_to_writebump; | |
de89de6e | 2971 | wbc->range_start = range_start; |
9bffad1e | 2972 | trace_ext4_da_writepages_result(inode, wbc, ret, pages_written); |
61628a3f | 2973 | return ret; |
64769240 AT |
2974 | } |
2975 | ||
79f0be8d AK |
2976 | #define FALL_BACK_TO_NONDELALLOC 1 |
2977 | static int ext4_nonda_switch(struct super_block *sb) | |
2978 | { | |
2979 | s64 free_blocks, dirty_blocks; | |
2980 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2981 | ||
2982 | /* | |
2983 | * switch to non delalloc mode if we are running low | |
2984 | * on free block. The free block accounting via percpu | |
179f7ebf | 2985 | * counters can get slightly wrong with percpu_counter_batch getting |
79f0be8d AK |
2986 | * accumulated on each CPU without updating global counters |
2987 | * Delalloc need an accurate free block accounting. So switch | |
2988 | * to non delalloc when we are near to error range. | |
2989 | */ | |
2990 | free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter); | |
2991 | dirty_blocks = percpu_counter_read_positive(&sbi->s_dirtyblocks_counter); | |
2992 | if (2 * free_blocks < 3 * dirty_blocks || | |
2993 | free_blocks < (dirty_blocks + EXT4_FREEBLOCKS_WATERMARK)) { | |
2994 | /* | |
2995 | * free block count is less that 150% of dirty blocks | |
2996 | * or free blocks is less that watermark | |
2997 | */ | |
2998 | return 1; | |
2999 | } | |
3000 | return 0; | |
3001 | } | |
3002 | ||
64769240 | 3003 | static int ext4_da_write_begin(struct file *file, struct address_space *mapping, |
de9a55b8 TT |
3004 | loff_t pos, unsigned len, unsigned flags, |
3005 | struct page **pagep, void **fsdata) | |
64769240 | 3006 | { |
d2a17637 | 3007 | int ret, retries = 0; |
64769240 AT |
3008 | struct page *page; |
3009 | pgoff_t index; | |
3010 | unsigned from, to; | |
3011 | struct inode *inode = mapping->host; | |
3012 | handle_t *handle; | |
3013 | ||
3014 | index = pos >> PAGE_CACHE_SHIFT; | |
3015 | from = pos & (PAGE_CACHE_SIZE - 1); | |
3016 | to = from + len; | |
79f0be8d AK |
3017 | |
3018 | if (ext4_nonda_switch(inode->i_sb)) { | |
3019 | *fsdata = (void *)FALL_BACK_TO_NONDELALLOC; | |
3020 | return ext4_write_begin(file, mapping, pos, | |
3021 | len, flags, pagep, fsdata); | |
3022 | } | |
3023 | *fsdata = (void *)0; | |
9bffad1e | 3024 | trace_ext4_da_write_begin(inode, pos, len, flags); |
d2a17637 | 3025 | retry: |
64769240 AT |
3026 | /* |
3027 | * With delayed allocation, we don't log the i_disksize update | |
3028 | * if there is delayed block allocation. But we still need | |
3029 | * to journalling the i_disksize update if writes to the end | |
3030 | * of file which has an already mapped buffer. | |
3031 | */ | |
3032 | handle = ext4_journal_start(inode, 1); | |
3033 | if (IS_ERR(handle)) { | |
3034 | ret = PTR_ERR(handle); | |
3035 | goto out; | |
3036 | } | |
ebd3610b JK |
3037 | /* We cannot recurse into the filesystem as the transaction is already |
3038 | * started */ | |
3039 | flags |= AOP_FLAG_NOFS; | |
64769240 | 3040 | |
54566b2c | 3041 | page = grab_cache_page_write_begin(mapping, index, flags); |
d5a0d4f7 ES |
3042 | if (!page) { |
3043 | ext4_journal_stop(handle); | |
3044 | ret = -ENOMEM; | |
3045 | goto out; | |
3046 | } | |
64769240 AT |
3047 | *pagep = page; |
3048 | ||
3049 | ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, | |
b920c755 | 3050 | ext4_da_get_block_prep); |
64769240 AT |
3051 | if (ret < 0) { |
3052 | unlock_page(page); | |
3053 | ext4_journal_stop(handle); | |
3054 | page_cache_release(page); | |
ae4d5372 AK |
3055 | /* |
3056 | * block_write_begin may have instantiated a few blocks | |
3057 | * outside i_size. Trim these off again. Don't need | |
3058 | * i_size_read because we hold i_mutex. | |
3059 | */ | |
3060 | if (pos + len > inode->i_size) | |
b9a4207d | 3061 | ext4_truncate_failed_write(inode); |
64769240 AT |
3062 | } |
3063 | ||
d2a17637 MC |
3064 | if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) |
3065 | goto retry; | |
64769240 AT |
3066 | out: |
3067 | return ret; | |
3068 | } | |
3069 | ||
632eaeab MC |
3070 | /* |
3071 | * Check if we should update i_disksize | |
3072 | * when write to the end of file but not require block allocation | |
3073 | */ | |
3074 | static int ext4_da_should_update_i_disksize(struct page *page, | |
de9a55b8 | 3075 | unsigned long offset) |
632eaeab MC |
3076 | { |
3077 | struct buffer_head *bh; | |
3078 | struct inode *inode = page->mapping->host; | |
3079 | unsigned int idx; | |
3080 | int i; | |
3081 | ||
3082 | bh = page_buffers(page); | |
3083 | idx = offset >> inode->i_blkbits; | |
3084 | ||
af5bc92d | 3085 | for (i = 0; i < idx; i++) |
632eaeab MC |
3086 | bh = bh->b_this_page; |
3087 | ||
29fa89d0 | 3088 | if (!buffer_mapped(bh) || (buffer_delay(bh)) || buffer_unwritten(bh)) |
632eaeab MC |
3089 | return 0; |
3090 | return 1; | |
3091 | } | |
3092 | ||
64769240 | 3093 | static int ext4_da_write_end(struct file *file, |
de9a55b8 TT |
3094 | struct address_space *mapping, |
3095 | loff_t pos, unsigned len, unsigned copied, | |
3096 | struct page *page, void *fsdata) | |
64769240 AT |
3097 | { |
3098 | struct inode *inode = mapping->host; | |
3099 | int ret = 0, ret2; | |
3100 | handle_t *handle = ext4_journal_current_handle(); | |
3101 | loff_t new_i_size; | |
632eaeab | 3102 | unsigned long start, end; |
79f0be8d AK |
3103 | int write_mode = (int)(unsigned long)fsdata; |
3104 | ||
3105 | if (write_mode == FALL_BACK_TO_NONDELALLOC) { | |
3106 | if (ext4_should_order_data(inode)) { | |
3107 | return ext4_ordered_write_end(file, mapping, pos, | |
3108 | len, copied, page, fsdata); | |
3109 | } else if (ext4_should_writeback_data(inode)) { | |
3110 | return ext4_writeback_write_end(file, mapping, pos, | |
3111 | len, copied, page, fsdata); | |
3112 | } else { | |
3113 | BUG(); | |
3114 | } | |
3115 | } | |
632eaeab | 3116 | |
9bffad1e | 3117 | trace_ext4_da_write_end(inode, pos, len, copied); |
632eaeab | 3118 | start = pos & (PAGE_CACHE_SIZE - 1); |
af5bc92d | 3119 | end = start + copied - 1; |
64769240 AT |
3120 | |
3121 | /* | |
3122 | * generic_write_end() will run mark_inode_dirty() if i_size | |
3123 | * changes. So let's piggyback the i_disksize mark_inode_dirty | |
3124 | * into that. | |
3125 | */ | |
3126 | ||
3127 | new_i_size = pos + copied; | |
632eaeab MC |
3128 | if (new_i_size > EXT4_I(inode)->i_disksize) { |
3129 | if (ext4_da_should_update_i_disksize(page, end)) { | |
3130 | down_write(&EXT4_I(inode)->i_data_sem); | |
3131 | if (new_i_size > EXT4_I(inode)->i_disksize) { | |
3132 | /* | |
3133 | * Updating i_disksize when extending file | |
3134 | * without needing block allocation | |
3135 | */ | |
3136 | if (ext4_should_order_data(inode)) | |
3137 | ret = ext4_jbd2_file_inode(handle, | |
3138 | inode); | |
64769240 | 3139 | |
632eaeab MC |
3140 | EXT4_I(inode)->i_disksize = new_i_size; |
3141 | } | |
3142 | up_write(&EXT4_I(inode)->i_data_sem); | |
cf17fea6 AK |
3143 | /* We need to mark inode dirty even if |
3144 | * new_i_size is less that inode->i_size | |
3145 | * bu greater than i_disksize.(hint delalloc) | |
3146 | */ | |
3147 | ext4_mark_inode_dirty(handle, inode); | |
64769240 | 3148 | } |
632eaeab | 3149 | } |
64769240 AT |
3150 | ret2 = generic_write_end(file, mapping, pos, len, copied, |
3151 | page, fsdata); | |
3152 | copied = ret2; | |
3153 | if (ret2 < 0) | |
3154 | ret = ret2; | |
3155 | ret2 = ext4_journal_stop(handle); | |
3156 | if (!ret) | |
3157 | ret = ret2; | |
3158 | ||
3159 | return ret ? ret : copied; | |
3160 | } | |
3161 | ||
3162 | static void ext4_da_invalidatepage(struct page *page, unsigned long offset) | |
3163 | { | |
64769240 AT |
3164 | /* |
3165 | * Drop reserved blocks | |
3166 | */ | |
3167 | BUG_ON(!PageLocked(page)); | |
3168 | if (!page_has_buffers(page)) | |
3169 | goto out; | |
3170 | ||
d2a17637 | 3171 | ext4_da_page_release_reservation(page, offset); |
64769240 AT |
3172 | |
3173 | out: | |
3174 | ext4_invalidatepage(page, offset); | |
3175 | ||
3176 | return; | |
3177 | } | |
3178 | ||
ccd2506b TT |
3179 | /* |
3180 | * Force all delayed allocation blocks to be allocated for a given inode. | |
3181 | */ | |
3182 | int ext4_alloc_da_blocks(struct inode *inode) | |
3183 | { | |
fb40ba0d TT |
3184 | trace_ext4_alloc_da_blocks(inode); |
3185 | ||
ccd2506b TT |
3186 | if (!EXT4_I(inode)->i_reserved_data_blocks && |
3187 | !EXT4_I(inode)->i_reserved_meta_blocks) | |
3188 | return 0; | |
3189 | ||
3190 | /* | |
3191 | * We do something simple for now. The filemap_flush() will | |
3192 | * also start triggering a write of the data blocks, which is | |
3193 | * not strictly speaking necessary (and for users of | |
3194 | * laptop_mode, not even desirable). However, to do otherwise | |
3195 | * would require replicating code paths in: | |
de9a55b8 | 3196 | * |
ccd2506b TT |
3197 | * ext4_da_writepages() -> |
3198 | * write_cache_pages() ---> (via passed in callback function) | |
3199 | * __mpage_da_writepage() --> | |
3200 | * mpage_add_bh_to_extent() | |
3201 | * mpage_da_map_blocks() | |
3202 | * | |
3203 | * The problem is that write_cache_pages(), located in | |
3204 | * mm/page-writeback.c, marks pages clean in preparation for | |
3205 | * doing I/O, which is not desirable if we're not planning on | |
3206 | * doing I/O at all. | |
3207 | * | |
3208 | * We could call write_cache_pages(), and then redirty all of | |
3209 | * the pages by calling redirty_page_for_writeback() but that | |
3210 | * would be ugly in the extreme. So instead we would need to | |
3211 | * replicate parts of the code in the above functions, | |
3212 | * simplifying them becuase we wouldn't actually intend to | |
3213 | * write out the pages, but rather only collect contiguous | |
3214 | * logical block extents, call the multi-block allocator, and | |
3215 | * then update the buffer heads with the block allocations. | |
de9a55b8 | 3216 | * |
ccd2506b TT |
3217 | * For now, though, we'll cheat by calling filemap_flush(), |
3218 | * which will map the blocks, and start the I/O, but not | |
3219 | * actually wait for the I/O to complete. | |
3220 | */ | |
3221 | return filemap_flush(inode->i_mapping); | |
3222 | } | |
64769240 | 3223 | |
ac27a0ec DK |
3224 | /* |
3225 | * bmap() is special. It gets used by applications such as lilo and by | |
3226 | * the swapper to find the on-disk block of a specific piece of data. | |
3227 | * | |
3228 | * Naturally, this is dangerous if the block concerned is still in the | |
617ba13b | 3229 | * journal. If somebody makes a swapfile on an ext4 data-journaling |
ac27a0ec DK |
3230 | * filesystem and enables swap, then they may get a nasty shock when the |
3231 | * data getting swapped to that swapfile suddenly gets overwritten by | |
3232 | * the original zero's written out previously to the journal and | |
3233 | * awaiting writeback in the kernel's buffer cache. | |
3234 | * | |
3235 | * So, if we see any bmap calls here on a modified, data-journaled file, | |
3236 | * take extra steps to flush any blocks which might be in the cache. | |
3237 | */ | |
617ba13b | 3238 | static sector_t ext4_bmap(struct address_space *mapping, sector_t block) |
ac27a0ec DK |
3239 | { |
3240 | struct inode *inode = mapping->host; | |
3241 | journal_t *journal; | |
3242 | int err; | |
3243 | ||
64769240 AT |
3244 | if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) && |
3245 | test_opt(inode->i_sb, DELALLOC)) { | |
3246 | /* | |
3247 | * With delalloc we want to sync the file | |
3248 | * so that we can make sure we allocate | |
3249 | * blocks for file | |
3250 | */ | |
3251 | filemap_write_and_wait(mapping); | |
3252 | } | |
3253 | ||
0390131b | 3254 | if (EXT4_JOURNAL(inode) && EXT4_I(inode)->i_state & EXT4_STATE_JDATA) { |
ac27a0ec DK |
3255 | /* |
3256 | * This is a REALLY heavyweight approach, but the use of | |
3257 | * bmap on dirty files is expected to be extremely rare: | |
3258 | * only if we run lilo or swapon on a freshly made file | |
3259 | * do we expect this to happen. | |
3260 | * | |
3261 | * (bmap requires CAP_SYS_RAWIO so this does not | |
3262 | * represent an unprivileged user DOS attack --- we'd be | |
3263 | * in trouble if mortal users could trigger this path at | |
3264 | * will.) | |
3265 | * | |
617ba13b | 3266 | * NB. EXT4_STATE_JDATA is not set on files other than |
ac27a0ec DK |
3267 | * regular files. If somebody wants to bmap a directory |
3268 | * or symlink and gets confused because the buffer | |
3269 | * hasn't yet been flushed to disk, they deserve | |
3270 | * everything they get. | |
3271 | */ | |
3272 | ||
617ba13b MC |
3273 | EXT4_I(inode)->i_state &= ~EXT4_STATE_JDATA; |
3274 | journal = EXT4_JOURNAL(inode); | |
dab291af MC |
3275 | jbd2_journal_lock_updates(journal); |
3276 | err = jbd2_journal_flush(journal); | |
3277 | jbd2_journal_unlock_updates(journal); | |
ac27a0ec DK |
3278 | |
3279 | if (err) | |
3280 | return 0; | |
3281 | } | |
3282 | ||
af5bc92d | 3283 | return generic_block_bmap(mapping, block, ext4_get_block); |
ac27a0ec DK |
3284 | } |
3285 | ||
617ba13b | 3286 | static int ext4_readpage(struct file *file, struct page *page) |
ac27a0ec | 3287 | { |
617ba13b | 3288 | return mpage_readpage(page, ext4_get_block); |
ac27a0ec DK |
3289 | } |
3290 | ||
3291 | static int | |
617ba13b | 3292 | ext4_readpages(struct file *file, struct address_space *mapping, |
ac27a0ec DK |
3293 | struct list_head *pages, unsigned nr_pages) |
3294 | { | |
617ba13b | 3295 | return mpage_readpages(mapping, pages, nr_pages, ext4_get_block); |
ac27a0ec DK |
3296 | } |
3297 | ||
617ba13b | 3298 | static void ext4_invalidatepage(struct page *page, unsigned long offset) |
ac27a0ec | 3299 | { |
617ba13b | 3300 | journal_t *journal = EXT4_JOURNAL(page->mapping->host); |
ac27a0ec DK |
3301 | |
3302 | /* | |
3303 | * If it's a full truncate we just forget about the pending dirtying | |
3304 | */ | |
3305 | if (offset == 0) | |
3306 | ClearPageChecked(page); | |
3307 | ||
0390131b FM |
3308 | if (journal) |
3309 | jbd2_journal_invalidatepage(journal, page, offset); | |
3310 | else | |
3311 | block_invalidatepage(page, offset); | |
ac27a0ec DK |
3312 | } |
3313 | ||
617ba13b | 3314 | static int ext4_releasepage(struct page *page, gfp_t wait) |
ac27a0ec | 3315 | { |
617ba13b | 3316 | journal_t *journal = EXT4_JOURNAL(page->mapping->host); |
ac27a0ec DK |
3317 | |
3318 | WARN_ON(PageChecked(page)); | |
3319 | if (!page_has_buffers(page)) | |
3320 | return 0; | |
0390131b FM |
3321 | if (journal) |
3322 | return jbd2_journal_try_to_free_buffers(journal, page, wait); | |
3323 | else | |
3324 | return try_to_free_buffers(page); | |
ac27a0ec DK |
3325 | } |
3326 | ||
3327 | /* | |
4c0425ff MC |
3328 | * O_DIRECT for ext3 (or indirect map) based files |
3329 | * | |
ac27a0ec DK |
3330 | * If the O_DIRECT write will extend the file then add this inode to the |
3331 | * orphan list. So recovery will truncate it back to the original size | |
3332 | * if the machine crashes during the write. | |
3333 | * | |
3334 | * If the O_DIRECT write is intantiating holes inside i_size and the machine | |
7fb5409d JK |
3335 | * crashes then stale disk data _may_ be exposed inside the file. But current |
3336 | * VFS code falls back into buffered path in that case so we are safe. | |
ac27a0ec | 3337 | */ |
4c0425ff | 3338 | static ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb, |
de9a55b8 TT |
3339 | const struct iovec *iov, loff_t offset, |
3340 | unsigned long nr_segs) | |
ac27a0ec DK |
3341 | { |
3342 | struct file *file = iocb->ki_filp; | |
3343 | struct inode *inode = file->f_mapping->host; | |
617ba13b | 3344 | struct ext4_inode_info *ei = EXT4_I(inode); |
7fb5409d | 3345 | handle_t *handle; |
ac27a0ec DK |
3346 | ssize_t ret; |
3347 | int orphan = 0; | |
3348 | size_t count = iov_length(iov, nr_segs); | |
fbbf6945 | 3349 | int retries = 0; |
ac27a0ec DK |
3350 | |
3351 | if (rw == WRITE) { | |
3352 | loff_t final_size = offset + count; | |
3353 | ||
ac27a0ec | 3354 | if (final_size > inode->i_size) { |
7fb5409d JK |
3355 | /* Credits for sb + inode write */ |
3356 | handle = ext4_journal_start(inode, 2); | |
3357 | if (IS_ERR(handle)) { | |
3358 | ret = PTR_ERR(handle); | |
3359 | goto out; | |
3360 | } | |
617ba13b | 3361 | ret = ext4_orphan_add(handle, inode); |
7fb5409d JK |
3362 | if (ret) { |
3363 | ext4_journal_stop(handle); | |
3364 | goto out; | |
3365 | } | |
ac27a0ec DK |
3366 | orphan = 1; |
3367 | ei->i_disksize = inode->i_size; | |
7fb5409d | 3368 | ext4_journal_stop(handle); |
ac27a0ec DK |
3369 | } |
3370 | } | |
3371 | ||
fbbf6945 | 3372 | retry: |
ac27a0ec DK |
3373 | ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov, |
3374 | offset, nr_segs, | |
617ba13b | 3375 | ext4_get_block, NULL); |
fbbf6945 ES |
3376 | if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) |
3377 | goto retry; | |
ac27a0ec | 3378 | |
7fb5409d | 3379 | if (orphan) { |
ac27a0ec DK |
3380 | int err; |
3381 | ||
7fb5409d JK |
3382 | /* Credits for sb + inode write */ |
3383 | handle = ext4_journal_start(inode, 2); | |
3384 | if (IS_ERR(handle)) { | |
3385 | /* This is really bad luck. We've written the data | |
3386 | * but cannot extend i_size. Bail out and pretend | |
3387 | * the write failed... */ | |
3388 | ret = PTR_ERR(handle); | |
3389 | goto out; | |
3390 | } | |
3391 | if (inode->i_nlink) | |
617ba13b | 3392 | ext4_orphan_del(handle, inode); |
7fb5409d | 3393 | if (ret > 0) { |
ac27a0ec DK |
3394 | loff_t end = offset + ret; |
3395 | if (end > inode->i_size) { | |
3396 | ei->i_disksize = end; | |
3397 | i_size_write(inode, end); | |
3398 | /* | |
3399 | * We're going to return a positive `ret' | |
3400 | * here due to non-zero-length I/O, so there's | |
3401 | * no way of reporting error returns from | |
617ba13b | 3402 | * ext4_mark_inode_dirty() to userspace. So |
ac27a0ec DK |
3403 | * ignore it. |
3404 | */ | |
617ba13b | 3405 | ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
3406 | } |
3407 | } | |
617ba13b | 3408 | err = ext4_journal_stop(handle); |
ac27a0ec DK |
3409 | if (ret == 0) |
3410 | ret = err; | |
3411 | } | |
3412 | out: | |
3413 | return ret; | |
3414 | } | |
3415 | ||
4c0425ff MC |
3416 | static int ext4_get_block_dio_write(struct inode *inode, sector_t iblock, |
3417 | struct buffer_head *bh_result, int create) | |
3418 | { | |
3419 | handle_t *handle = NULL; | |
3420 | int ret = 0; | |
3421 | unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; | |
3422 | int dio_credits; | |
3423 | ||
8d5d02e6 MC |
3424 | ext4_debug("ext4_get_block_dio_write: inode %lu, create flag %d\n", |
3425 | inode->i_ino, create); | |
4c0425ff MC |
3426 | /* |
3427 | * DIO VFS code passes create = 0 flag for write to | |
3428 | * the middle of file. It does this to avoid block | |
3429 | * allocation for holes, to prevent expose stale data | |
3430 | * out when there is parallel buffered read (which does | |
3431 | * not hold the i_mutex lock) while direct IO write has | |
3432 | * not completed. DIO request on holes finally falls back | |
3433 | * to buffered IO for this reason. | |
3434 | * | |
3435 | * For ext4 extent based file, since we support fallocate, | |
3436 | * new allocated extent as uninitialized, for holes, we | |
3437 | * could fallocate blocks for holes, thus parallel | |
3438 | * buffered IO read will zero out the page when read on | |
3439 | * a hole while parallel DIO write to the hole has not completed. | |
3440 | * | |
3441 | * when we come here, we know it's a direct IO write to | |
3442 | * to the middle of file (<i_size) | |
3443 | * so it's safe to override the create flag from VFS. | |
3444 | */ | |
3445 | create = EXT4_GET_BLOCKS_DIO_CREATE_EXT; | |
3446 | ||
3447 | if (max_blocks > DIO_MAX_BLOCKS) | |
3448 | max_blocks = DIO_MAX_BLOCKS; | |
3449 | dio_credits = ext4_chunk_trans_blocks(inode, max_blocks); | |
3450 | handle = ext4_journal_start(inode, dio_credits); | |
3451 | if (IS_ERR(handle)) { | |
3452 | ret = PTR_ERR(handle); | |
3453 | goto out; | |
3454 | } | |
3455 | ret = ext4_get_blocks(handle, inode, iblock, max_blocks, bh_result, | |
3456 | create); | |
3457 | if (ret > 0) { | |
3458 | bh_result->b_size = (ret << inode->i_blkbits); | |
3459 | ret = 0; | |
3460 | } | |
3461 | ext4_journal_stop(handle); | |
3462 | out: | |
3463 | return ret; | |
3464 | } | |
3465 | ||
4c0425ff MC |
3466 | static void ext4_free_io_end(ext4_io_end_t *io) |
3467 | { | |
8d5d02e6 MC |
3468 | BUG_ON(!io); |
3469 | iput(io->inode); | |
4c0425ff MC |
3470 | kfree(io); |
3471 | } | |
8d5d02e6 MC |
3472 | static void dump_aio_dio_list(struct inode * inode) |
3473 | { | |
3474 | #ifdef EXT4_DEBUG | |
3475 | struct list_head *cur, *before, *after; | |
3476 | ext4_io_end_t *io, *io0, *io1; | |
3477 | ||
3478 | if (list_empty(&EXT4_I(inode)->i_aio_dio_complete_list)){ | |
3479 | ext4_debug("inode %lu aio dio list is empty\n", inode->i_ino); | |
3480 | return; | |
3481 | } | |
3482 | ||
3483 | ext4_debug("Dump inode %lu aio_dio_completed_IO list \n", inode->i_ino); | |
3484 | list_for_each_entry(io, &EXT4_I(inode)->i_aio_dio_complete_list, list){ | |
3485 | cur = &io->list; | |
3486 | before = cur->prev; | |
3487 | io0 = container_of(before, ext4_io_end_t, list); | |
3488 | after = cur->next; | |
3489 | io1 = container_of(after, ext4_io_end_t, list); | |
3490 | ||
3491 | ext4_debug("io 0x%p from inode %lu,prev 0x%p,next 0x%p\n", | |
3492 | io, inode->i_ino, io0, io1); | |
3493 | } | |
3494 | #endif | |
3495 | } | |
4c0425ff MC |
3496 | |
3497 | /* | |
4c0425ff MC |
3498 | * check a range of space and convert unwritten extents to written. |
3499 | */ | |
8d5d02e6 | 3500 | static int ext4_end_aio_dio_nolock(ext4_io_end_t *io) |
4c0425ff | 3501 | { |
4c0425ff MC |
3502 | struct inode *inode = io->inode; |
3503 | loff_t offset = io->offset; | |
3504 | size_t size = io->size; | |
3505 | int ret = 0; | |
4c0425ff | 3506 | |
8d5d02e6 MC |
3507 | ext4_debug("end_aio_dio_onlock: io 0x%p from inode %lu,list->next 0x%p," |
3508 | "list->prev 0x%p\n", | |
3509 | io, inode->i_ino, io->list.next, io->list.prev); | |
3510 | ||
3511 | if (list_empty(&io->list)) | |
3512 | return ret; | |
3513 | ||
3514 | if (io->flag != DIO_AIO_UNWRITTEN) | |
3515 | return ret; | |
3516 | ||
4c0425ff MC |
3517 | if (offset + size <= i_size_read(inode)) |
3518 | ret = ext4_convert_unwritten_extents(inode, offset, size); | |
3519 | ||
8d5d02e6 | 3520 | if (ret < 0) { |
4c0425ff | 3521 | printk(KERN_EMERG "%s: failed to convert unwritten" |
8d5d02e6 MC |
3522 | "extents to written extents, error is %d" |
3523 | " io is still on inode %lu aio dio list\n", | |
3524 | __func__, ret, inode->i_ino); | |
3525 | return ret; | |
3526 | } | |
4c0425ff | 3527 | |
8d5d02e6 MC |
3528 | /* clear the DIO AIO unwritten flag */ |
3529 | io->flag = 0; | |
3530 | return ret; | |
4c0425ff | 3531 | } |
8d5d02e6 MC |
3532 | /* |
3533 | * work on completed aio dio IO, to convert unwritten extents to extents | |
3534 | */ | |
3535 | static void ext4_end_aio_dio_work(struct work_struct *work) | |
3536 | { | |
3537 | ext4_io_end_t *io = container_of(work, ext4_io_end_t, work); | |
3538 | struct inode *inode = io->inode; | |
3539 | int ret = 0; | |
4c0425ff | 3540 | |
8d5d02e6 MC |
3541 | mutex_lock(&inode->i_mutex); |
3542 | ret = ext4_end_aio_dio_nolock(io); | |
3543 | if (ret >= 0) { | |
3544 | if (!list_empty(&io->list)) | |
3545 | list_del_init(&io->list); | |
3546 | ext4_free_io_end(io); | |
3547 | } | |
3548 | mutex_unlock(&inode->i_mutex); | |
3549 | } | |
3550 | /* | |
3551 | * This function is called from ext4_sync_file(). | |
3552 | * | |
3553 | * When AIO DIO IO is completed, the work to convert unwritten | |
3554 | * extents to written is queued on workqueue but may not get immediately | |
3555 | * scheduled. When fsync is called, we need to ensure the | |
3556 | * conversion is complete before fsync returns. | |
3557 | * The inode keeps track of a list of completed AIO from DIO path | |
3558 | * that might needs to do the conversion. This function walks through | |
3559 | * the list and convert the related unwritten extents to written. | |
3560 | */ | |
3561 | int flush_aio_dio_completed_IO(struct inode *inode) | |
3562 | { | |
3563 | ext4_io_end_t *io; | |
3564 | int ret = 0; | |
3565 | int ret2 = 0; | |
3566 | ||
3567 | if (list_empty(&EXT4_I(inode)->i_aio_dio_complete_list)) | |
3568 | return ret; | |
3569 | ||
3570 | dump_aio_dio_list(inode); | |
3571 | while (!list_empty(&EXT4_I(inode)->i_aio_dio_complete_list)){ | |
3572 | io = list_entry(EXT4_I(inode)->i_aio_dio_complete_list.next, | |
3573 | ext4_io_end_t, list); | |
3574 | /* | |
3575 | * Calling ext4_end_aio_dio_nolock() to convert completed | |
3576 | * IO to written. | |
3577 | * | |
3578 | * When ext4_sync_file() is called, run_queue() may already | |
3579 | * about to flush the work corresponding to this io structure. | |
3580 | * It will be upset if it founds the io structure related | |
3581 | * to the work-to-be schedule is freed. | |
3582 | * | |
3583 | * Thus we need to keep the io structure still valid here after | |
3584 | * convertion finished. The io structure has a flag to | |
3585 | * avoid double converting from both fsync and background work | |
3586 | * queue work. | |
3587 | */ | |
3588 | ret = ext4_end_aio_dio_nolock(io); | |
3589 | if (ret < 0) | |
3590 | ret2 = ret; | |
3591 | else | |
3592 | list_del_init(&io->list); | |
3593 | } | |
3594 | return (ret2 < 0) ? ret2 : 0; | |
3595 | } | |
3596 | ||
3597 | static ext4_io_end_t *ext4_init_io_end (struct inode *inode) | |
4c0425ff MC |
3598 | { |
3599 | ext4_io_end_t *io = NULL; | |
3600 | ||
3601 | io = kmalloc(sizeof(*io), GFP_NOFS); | |
3602 | ||
3603 | if (io) { | |
8d5d02e6 | 3604 | igrab(inode); |
4c0425ff | 3605 | io->inode = inode; |
8d5d02e6 | 3606 | io->flag = 0; |
4c0425ff MC |
3607 | io->offset = 0; |
3608 | io->size = 0; | |
3609 | io->error = 0; | |
8d5d02e6 MC |
3610 | INIT_WORK(&io->work, ext4_end_aio_dio_work); |
3611 | INIT_LIST_HEAD(&io->list); | |
4c0425ff MC |
3612 | } |
3613 | ||
3614 | return io; | |
3615 | } | |
3616 | ||
3617 | static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset, | |
3618 | ssize_t size, void *private) | |
3619 | { | |
3620 | ext4_io_end_t *io_end = iocb->private; | |
3621 | struct workqueue_struct *wq; | |
3622 | ||
4b70df18 M |
3623 | /* if not async direct IO or dio with 0 bytes write, just return */ |
3624 | if (!io_end || !size) | |
3625 | return; | |
3626 | ||
8d5d02e6 MC |
3627 | ext_debug("ext4_end_io_dio(): io_end 0x%p" |
3628 | "for inode %lu, iocb 0x%p, offset %llu, size %llu\n", | |
3629 | iocb->private, io_end->inode->i_ino, iocb, offset, | |
3630 | size); | |
8d5d02e6 MC |
3631 | |
3632 | /* if not aio dio with unwritten extents, just free io and return */ | |
3633 | if (io_end->flag != DIO_AIO_UNWRITTEN){ | |
3634 | ext4_free_io_end(io_end); | |
3635 | iocb->private = NULL; | |
4c0425ff | 3636 | return; |
8d5d02e6 MC |
3637 | } |
3638 | ||
4c0425ff MC |
3639 | io_end->offset = offset; |
3640 | io_end->size = size; | |
3641 | wq = EXT4_SB(io_end->inode->i_sb)->dio_unwritten_wq; | |
3642 | ||
8d5d02e6 | 3643 | /* queue the work to convert unwritten extents to written */ |
4c0425ff MC |
3644 | queue_work(wq, &io_end->work); |
3645 | ||
8d5d02e6 MC |
3646 | /* Add the io_end to per-inode completed aio dio list*/ |
3647 | list_add_tail(&io_end->list, | |
3648 | &EXT4_I(io_end->inode)->i_aio_dio_complete_list); | |
4c0425ff MC |
3649 | iocb->private = NULL; |
3650 | } | |
3651 | /* | |
3652 | * For ext4 extent files, ext4 will do direct-io write to holes, | |
3653 | * preallocated extents, and those write extend the file, no need to | |
3654 | * fall back to buffered IO. | |
3655 | * | |
3656 | * For holes, we fallocate those blocks, mark them as unintialized | |
3657 | * If those blocks were preallocated, we mark sure they are splited, but | |
3658 | * still keep the range to write as unintialized. | |
3659 | * | |
8d5d02e6 MC |
3660 | * The unwrritten extents will be converted to written when DIO is completed. |
3661 | * For async direct IO, since the IO may still pending when return, we | |
3662 | * set up an end_io call back function, which will do the convertion | |
3663 | * when async direct IO completed. | |
4c0425ff MC |
3664 | * |
3665 | * If the O_DIRECT write will extend the file then add this inode to the | |
3666 | * orphan list. So recovery will truncate it back to the original size | |
3667 | * if the machine crashes during the write. | |
3668 | * | |
3669 | */ | |
3670 | static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb, | |
3671 | const struct iovec *iov, loff_t offset, | |
3672 | unsigned long nr_segs) | |
3673 | { | |
3674 | struct file *file = iocb->ki_filp; | |
3675 | struct inode *inode = file->f_mapping->host; | |
3676 | ssize_t ret; | |
3677 | size_t count = iov_length(iov, nr_segs); | |
3678 | ||
3679 | loff_t final_size = offset + count; | |
3680 | if (rw == WRITE && final_size <= inode->i_size) { | |
3681 | /* | |
8d5d02e6 MC |
3682 | * We could direct write to holes and fallocate. |
3683 | * | |
3684 | * Allocated blocks to fill the hole are marked as uninitialized | |
4c0425ff MC |
3685 | * to prevent paralel buffered read to expose the stale data |
3686 | * before DIO complete the data IO. | |
8d5d02e6 MC |
3687 | * |
3688 | * As to previously fallocated extents, ext4 get_block | |
4c0425ff MC |
3689 | * will just simply mark the buffer mapped but still |
3690 | * keep the extents uninitialized. | |
3691 | * | |
8d5d02e6 MC |
3692 | * for non AIO case, we will convert those unwritten extents |
3693 | * to written after return back from blockdev_direct_IO. | |
3694 | * | |
3695 | * for async DIO, the conversion needs to be defered when | |
3696 | * the IO is completed. The ext4 end_io callback function | |
3697 | * will be called to take care of the conversion work. | |
3698 | * Here for async case, we allocate an io_end structure to | |
3699 | * hook to the iocb. | |
4c0425ff | 3700 | */ |
8d5d02e6 MC |
3701 | iocb->private = NULL; |
3702 | EXT4_I(inode)->cur_aio_dio = NULL; | |
3703 | if (!is_sync_kiocb(iocb)) { | |
3704 | iocb->private = ext4_init_io_end(inode); | |
3705 | if (!iocb->private) | |
3706 | return -ENOMEM; | |
3707 | /* | |
3708 | * we save the io structure for current async | |
3709 | * direct IO, so that later ext4_get_blocks() | |
3710 | * could flag the io structure whether there | |
3711 | * is a unwritten extents needs to be converted | |
3712 | * when IO is completed. | |
3713 | */ | |
3714 | EXT4_I(inode)->cur_aio_dio = iocb->private; | |
3715 | } | |
3716 | ||
4c0425ff MC |
3717 | ret = blockdev_direct_IO(rw, iocb, inode, |
3718 | inode->i_sb->s_bdev, iov, | |
3719 | offset, nr_segs, | |
3720 | ext4_get_block_dio_write, | |
3721 | ext4_end_io_dio); | |
8d5d02e6 MC |
3722 | if (iocb->private) |
3723 | EXT4_I(inode)->cur_aio_dio = NULL; | |
3724 | /* | |
3725 | * The io_end structure takes a reference to the inode, | |
3726 | * that structure needs to be destroyed and the | |
3727 | * reference to the inode need to be dropped, when IO is | |
3728 | * complete, even with 0 byte write, or failed. | |
3729 | * | |
3730 | * In the successful AIO DIO case, the io_end structure will be | |
3731 | * desctroyed and the reference to the inode will be dropped | |
3732 | * after the end_io call back function is called. | |
3733 | * | |
3734 | * In the case there is 0 byte write, or error case, since | |
3735 | * VFS direct IO won't invoke the end_io call back function, | |
3736 | * we need to free the end_io structure here. | |
3737 | */ | |
3738 | if (ret != -EIOCBQUEUED && ret <= 0 && iocb->private) { | |
3739 | ext4_free_io_end(iocb->private); | |
3740 | iocb->private = NULL; | |
5f524950 M |
3741 | } else if (ret > 0 && (EXT4_I(inode)->i_state & |
3742 | EXT4_STATE_DIO_UNWRITTEN)) { | |
109f5565 | 3743 | int err; |
8d5d02e6 MC |
3744 | /* |
3745 | * for non AIO case, since the IO is already | |
3746 | * completed, we could do the convertion right here | |
3747 | */ | |
109f5565 M |
3748 | err = ext4_convert_unwritten_extents(inode, |
3749 | offset, ret); | |
3750 | if (err < 0) | |
3751 | ret = err; | |
5f524950 | 3752 | EXT4_I(inode)->i_state &= ~EXT4_STATE_DIO_UNWRITTEN; |
109f5565 | 3753 | } |
4c0425ff MC |
3754 | return ret; |
3755 | } | |
8d5d02e6 MC |
3756 | |
3757 | /* for write the the end of file case, we fall back to old way */ | |
4c0425ff MC |
3758 | return ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs); |
3759 | } | |
3760 | ||
3761 | static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb, | |
3762 | const struct iovec *iov, loff_t offset, | |
3763 | unsigned long nr_segs) | |
3764 | { | |
3765 | struct file *file = iocb->ki_filp; | |
3766 | struct inode *inode = file->f_mapping->host; | |
3767 | ||
3768 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) | |
3769 | return ext4_ext_direct_IO(rw, iocb, iov, offset, nr_segs); | |
3770 | ||
3771 | return ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs); | |
3772 | } | |
3773 | ||
ac27a0ec | 3774 | /* |
617ba13b | 3775 | * Pages can be marked dirty completely asynchronously from ext4's journalling |
ac27a0ec DK |
3776 | * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do |
3777 | * much here because ->set_page_dirty is called under VFS locks. The page is | |
3778 | * not necessarily locked. | |
3779 | * | |
3780 | * We cannot just dirty the page and leave attached buffers clean, because the | |
3781 | * buffers' dirty state is "definitive". We cannot just set the buffers dirty | |
3782 | * or jbddirty because all the journalling code will explode. | |
3783 | * | |
3784 | * So what we do is to mark the page "pending dirty" and next time writepage | |
3785 | * is called, propagate that into the buffers appropriately. | |
3786 | */ | |
617ba13b | 3787 | static int ext4_journalled_set_page_dirty(struct page *page) |
ac27a0ec DK |
3788 | { |
3789 | SetPageChecked(page); | |
3790 | return __set_page_dirty_nobuffers(page); | |
3791 | } | |
3792 | ||
617ba13b | 3793 | static const struct address_space_operations ext4_ordered_aops = { |
8ab22b9a HH |
3794 | .readpage = ext4_readpage, |
3795 | .readpages = ext4_readpages, | |
43ce1d23 | 3796 | .writepage = ext4_writepage, |
8ab22b9a HH |
3797 | .sync_page = block_sync_page, |
3798 | .write_begin = ext4_write_begin, | |
3799 | .write_end = ext4_ordered_write_end, | |
3800 | .bmap = ext4_bmap, | |
3801 | .invalidatepage = ext4_invalidatepage, | |
3802 | .releasepage = ext4_releasepage, | |
3803 | .direct_IO = ext4_direct_IO, | |
3804 | .migratepage = buffer_migrate_page, | |
3805 | .is_partially_uptodate = block_is_partially_uptodate, | |
aa261f54 | 3806 | .error_remove_page = generic_error_remove_page, |
ac27a0ec DK |
3807 | }; |
3808 | ||
617ba13b | 3809 | static const struct address_space_operations ext4_writeback_aops = { |
8ab22b9a HH |
3810 | .readpage = ext4_readpage, |
3811 | .readpages = ext4_readpages, | |
43ce1d23 | 3812 | .writepage = ext4_writepage, |
8ab22b9a HH |
3813 | .sync_page = block_sync_page, |
3814 | .write_begin = ext4_write_begin, | |
3815 | .write_end = ext4_writeback_write_end, | |
3816 | .bmap = ext4_bmap, | |
3817 | .invalidatepage = ext4_invalidatepage, | |
3818 | .releasepage = ext4_releasepage, | |
3819 | .direct_IO = ext4_direct_IO, | |
3820 | .migratepage = buffer_migrate_page, | |
3821 | .is_partially_uptodate = block_is_partially_uptodate, | |
aa261f54 | 3822 | .error_remove_page = generic_error_remove_page, |
ac27a0ec DK |
3823 | }; |
3824 | ||
617ba13b | 3825 | static const struct address_space_operations ext4_journalled_aops = { |
8ab22b9a HH |
3826 | .readpage = ext4_readpage, |
3827 | .readpages = ext4_readpages, | |
43ce1d23 | 3828 | .writepage = ext4_writepage, |
8ab22b9a HH |
3829 | .sync_page = block_sync_page, |
3830 | .write_begin = ext4_write_begin, | |
3831 | .write_end = ext4_journalled_write_end, | |
3832 | .set_page_dirty = ext4_journalled_set_page_dirty, | |
3833 | .bmap = ext4_bmap, | |
3834 | .invalidatepage = ext4_invalidatepage, | |
3835 | .releasepage = ext4_releasepage, | |
3836 | .is_partially_uptodate = block_is_partially_uptodate, | |
aa261f54 | 3837 | .error_remove_page = generic_error_remove_page, |
ac27a0ec DK |
3838 | }; |
3839 | ||
64769240 | 3840 | static const struct address_space_operations ext4_da_aops = { |
8ab22b9a HH |
3841 | .readpage = ext4_readpage, |
3842 | .readpages = ext4_readpages, | |
43ce1d23 | 3843 | .writepage = ext4_writepage, |
8ab22b9a HH |
3844 | .writepages = ext4_da_writepages, |
3845 | .sync_page = block_sync_page, | |
3846 | .write_begin = ext4_da_write_begin, | |
3847 | .write_end = ext4_da_write_end, | |
3848 | .bmap = ext4_bmap, | |
3849 | .invalidatepage = ext4_da_invalidatepage, | |
3850 | .releasepage = ext4_releasepage, | |
3851 | .direct_IO = ext4_direct_IO, | |
3852 | .migratepage = buffer_migrate_page, | |
3853 | .is_partially_uptodate = block_is_partially_uptodate, | |
aa261f54 | 3854 | .error_remove_page = generic_error_remove_page, |
64769240 AT |
3855 | }; |
3856 | ||
617ba13b | 3857 | void ext4_set_aops(struct inode *inode) |
ac27a0ec | 3858 | { |
cd1aac32 AK |
3859 | if (ext4_should_order_data(inode) && |
3860 | test_opt(inode->i_sb, DELALLOC)) | |
3861 | inode->i_mapping->a_ops = &ext4_da_aops; | |
3862 | else if (ext4_should_order_data(inode)) | |
617ba13b | 3863 | inode->i_mapping->a_ops = &ext4_ordered_aops; |
64769240 AT |
3864 | else if (ext4_should_writeback_data(inode) && |
3865 | test_opt(inode->i_sb, DELALLOC)) | |
3866 | inode->i_mapping->a_ops = &ext4_da_aops; | |
617ba13b MC |
3867 | else if (ext4_should_writeback_data(inode)) |
3868 | inode->i_mapping->a_ops = &ext4_writeback_aops; | |
ac27a0ec | 3869 | else |
617ba13b | 3870 | inode->i_mapping->a_ops = &ext4_journalled_aops; |
ac27a0ec DK |
3871 | } |
3872 | ||
3873 | /* | |
617ba13b | 3874 | * ext4_block_truncate_page() zeroes out a mapping from file offset `from' |
ac27a0ec DK |
3875 | * up to the end of the block which corresponds to `from'. |
3876 | * This required during truncate. We need to physically zero the tail end | |
3877 | * of that block so it doesn't yield old data if the file is later grown. | |
3878 | */ | |
cf108bca | 3879 | int ext4_block_truncate_page(handle_t *handle, |
ac27a0ec DK |
3880 | struct address_space *mapping, loff_t from) |
3881 | { | |
617ba13b | 3882 | ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT; |
ac27a0ec | 3883 | unsigned offset = from & (PAGE_CACHE_SIZE-1); |
725d26d3 AK |
3884 | unsigned blocksize, length, pos; |
3885 | ext4_lblk_t iblock; | |
ac27a0ec DK |
3886 | struct inode *inode = mapping->host; |
3887 | struct buffer_head *bh; | |
cf108bca | 3888 | struct page *page; |
ac27a0ec | 3889 | int err = 0; |
ac27a0ec | 3890 | |
f4a01017 TT |
3891 | page = find_or_create_page(mapping, from >> PAGE_CACHE_SHIFT, |
3892 | mapping_gfp_mask(mapping) & ~__GFP_FS); | |
cf108bca JK |
3893 | if (!page) |
3894 | return -EINVAL; | |
3895 | ||
ac27a0ec DK |
3896 | blocksize = inode->i_sb->s_blocksize; |
3897 | length = blocksize - (offset & (blocksize - 1)); | |
3898 | iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); | |
3899 | ||
3900 | /* | |
3901 | * For "nobh" option, we can only work if we don't need to | |
3902 | * read-in the page - otherwise we create buffers to do the IO. | |
3903 | */ | |
3904 | if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) && | |
617ba13b | 3905 | ext4_should_writeback_data(inode) && PageUptodate(page)) { |
eebd2aa3 | 3906 | zero_user(page, offset, length); |
ac27a0ec DK |
3907 | set_page_dirty(page); |
3908 | goto unlock; | |
3909 | } | |
3910 | ||
3911 | if (!page_has_buffers(page)) | |
3912 | create_empty_buffers(page, blocksize, 0); | |
3913 | ||
3914 | /* Find the buffer that contains "offset" */ | |
3915 | bh = page_buffers(page); | |
3916 | pos = blocksize; | |
3917 | while (offset >= pos) { | |
3918 | bh = bh->b_this_page; | |
3919 | iblock++; | |
3920 | pos += blocksize; | |
3921 | } | |
3922 | ||
3923 | err = 0; | |
3924 | if (buffer_freed(bh)) { | |
3925 | BUFFER_TRACE(bh, "freed: skip"); | |
3926 | goto unlock; | |
3927 | } | |
3928 | ||
3929 | if (!buffer_mapped(bh)) { | |
3930 | BUFFER_TRACE(bh, "unmapped"); | |
617ba13b | 3931 | ext4_get_block(inode, iblock, bh, 0); |
ac27a0ec DK |
3932 | /* unmapped? It's a hole - nothing to do */ |
3933 | if (!buffer_mapped(bh)) { | |
3934 | BUFFER_TRACE(bh, "still unmapped"); | |
3935 | goto unlock; | |
3936 | } | |
3937 | } | |
3938 | ||
3939 | /* Ok, it's mapped. Make sure it's up-to-date */ | |
3940 | if (PageUptodate(page)) | |
3941 | set_buffer_uptodate(bh); | |
3942 | ||
3943 | if (!buffer_uptodate(bh)) { | |
3944 | err = -EIO; | |
3945 | ll_rw_block(READ, 1, &bh); | |
3946 | wait_on_buffer(bh); | |
3947 | /* Uhhuh. Read error. Complain and punt. */ | |
3948 | if (!buffer_uptodate(bh)) | |
3949 | goto unlock; | |
3950 | } | |
3951 | ||
617ba13b | 3952 | if (ext4_should_journal_data(inode)) { |
ac27a0ec | 3953 | BUFFER_TRACE(bh, "get write access"); |
617ba13b | 3954 | err = ext4_journal_get_write_access(handle, bh); |
ac27a0ec DK |
3955 | if (err) |
3956 | goto unlock; | |
3957 | } | |
3958 | ||
eebd2aa3 | 3959 | zero_user(page, offset, length); |
ac27a0ec DK |
3960 | |
3961 | BUFFER_TRACE(bh, "zeroed end of block"); | |
3962 | ||
3963 | err = 0; | |
617ba13b | 3964 | if (ext4_should_journal_data(inode)) { |
0390131b | 3965 | err = ext4_handle_dirty_metadata(handle, inode, bh); |
ac27a0ec | 3966 | } else { |
617ba13b | 3967 | if (ext4_should_order_data(inode)) |
678aaf48 | 3968 | err = ext4_jbd2_file_inode(handle, inode); |
ac27a0ec DK |
3969 | mark_buffer_dirty(bh); |
3970 | } | |
3971 | ||
3972 | unlock: | |
3973 | unlock_page(page); | |
3974 | page_cache_release(page); | |
3975 | return err; | |
3976 | } | |
3977 | ||
3978 | /* | |
3979 | * Probably it should be a library function... search for first non-zero word | |
3980 | * or memcmp with zero_page, whatever is better for particular architecture. | |
3981 | * Linus? | |
3982 | */ | |
3983 | static inline int all_zeroes(__le32 *p, __le32 *q) | |
3984 | { | |
3985 | while (p < q) | |
3986 | if (*p++) | |
3987 | return 0; | |
3988 | return 1; | |
3989 | } | |
3990 | ||
3991 | /** | |
617ba13b | 3992 | * ext4_find_shared - find the indirect blocks for partial truncation. |
ac27a0ec DK |
3993 | * @inode: inode in question |
3994 | * @depth: depth of the affected branch | |
617ba13b | 3995 | * @offsets: offsets of pointers in that branch (see ext4_block_to_path) |
ac27a0ec DK |
3996 | * @chain: place to store the pointers to partial indirect blocks |
3997 | * @top: place to the (detached) top of branch | |
3998 | * | |
617ba13b | 3999 | * This is a helper function used by ext4_truncate(). |
ac27a0ec DK |
4000 | * |
4001 | * When we do truncate() we may have to clean the ends of several | |
4002 | * indirect blocks but leave the blocks themselves alive. Block is | |
4003 | * partially truncated if some data below the new i_size is refered | |
4004 | * from it (and it is on the path to the first completely truncated | |
4005 | * data block, indeed). We have to free the top of that path along | |
4006 | * with everything to the right of the path. Since no allocation | |
617ba13b | 4007 | * past the truncation point is possible until ext4_truncate() |
ac27a0ec DK |
4008 | * finishes, we may safely do the latter, but top of branch may |
4009 | * require special attention - pageout below the truncation point | |
4010 | * might try to populate it. | |
4011 | * | |
4012 | * We atomically detach the top of branch from the tree, store the | |
4013 | * block number of its root in *@top, pointers to buffer_heads of | |
4014 | * partially truncated blocks - in @chain[].bh and pointers to | |
4015 | * their last elements that should not be removed - in | |
4016 | * @chain[].p. Return value is the pointer to last filled element | |
4017 | * of @chain. | |
4018 | * | |
4019 | * The work left to caller to do the actual freeing of subtrees: | |
4020 | * a) free the subtree starting from *@top | |
4021 | * b) free the subtrees whose roots are stored in | |
4022 | * (@chain[i].p+1 .. end of @chain[i].bh->b_data) | |
4023 | * c) free the subtrees growing from the inode past the @chain[0]. | |
4024 | * (no partially truncated stuff there). */ | |
4025 | ||
617ba13b | 4026 | static Indirect *ext4_find_shared(struct inode *inode, int depth, |
de9a55b8 TT |
4027 | ext4_lblk_t offsets[4], Indirect chain[4], |
4028 | __le32 *top) | |
ac27a0ec DK |
4029 | { |
4030 | Indirect *partial, *p; | |
4031 | int k, err; | |
4032 | ||
4033 | *top = 0; | |
4034 | /* Make k index the deepest non-null offest + 1 */ | |
4035 | for (k = depth; k > 1 && !offsets[k-1]; k--) | |
4036 | ; | |
617ba13b | 4037 | partial = ext4_get_branch(inode, k, offsets, chain, &err); |
ac27a0ec DK |
4038 | /* Writer: pointers */ |
4039 | if (!partial) | |
4040 | partial = chain + k-1; | |
4041 | /* | |
4042 | * If the branch acquired continuation since we've looked at it - | |
4043 | * fine, it should all survive and (new) top doesn't belong to us. | |
4044 | */ | |
4045 | if (!partial->key && *partial->p) | |
4046 | /* Writer: end */ | |
4047 | goto no_top; | |
af5bc92d | 4048 | for (p = partial; (p > chain) && all_zeroes((__le32 *) p->bh->b_data, p->p); p--) |
ac27a0ec DK |
4049 | ; |
4050 | /* | |
4051 | * OK, we've found the last block that must survive. The rest of our | |
4052 | * branch should be detached before unlocking. However, if that rest | |
4053 | * of branch is all ours and does not grow immediately from the inode | |
4054 | * it's easier to cheat and just decrement partial->p. | |
4055 | */ | |
4056 | if (p == chain + k - 1 && p > chain) { | |
4057 | p->p--; | |
4058 | } else { | |
4059 | *top = *p->p; | |
617ba13b | 4060 | /* Nope, don't do this in ext4. Must leave the tree intact */ |
ac27a0ec DK |
4061 | #if 0 |
4062 | *p->p = 0; | |
4063 | #endif | |
4064 | } | |
4065 | /* Writer: end */ | |
4066 | ||
af5bc92d | 4067 | while (partial > p) { |
ac27a0ec DK |
4068 | brelse(partial->bh); |
4069 | partial--; | |
4070 | } | |
4071 | no_top: | |
4072 | return partial; | |
4073 | } | |
4074 | ||
4075 | /* | |
4076 | * Zero a number of block pointers in either an inode or an indirect block. | |
4077 | * If we restart the transaction we must again get write access to the | |
4078 | * indirect block for further modification. | |
4079 | * | |
4080 | * We release `count' blocks on disk, but (last - first) may be greater | |
4081 | * than `count' because there can be holes in there. | |
4082 | */ | |
617ba13b | 4083 | static void ext4_clear_blocks(handle_t *handle, struct inode *inode, |
de9a55b8 TT |
4084 | struct buffer_head *bh, |
4085 | ext4_fsblk_t block_to_free, | |
4086 | unsigned long count, __le32 *first, | |
4087 | __le32 *last) | |
ac27a0ec DK |
4088 | { |
4089 | __le32 *p; | |
e6362609 TT |
4090 | int flags = EXT4_FREE_BLOCKS_FORGET; |
4091 | ||
4092 | if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) | |
4093 | flags |= EXT4_FREE_BLOCKS_METADATA; | |
50689696 | 4094 | |
ac27a0ec DK |
4095 | if (try_to_extend_transaction(handle, inode)) { |
4096 | if (bh) { | |
0390131b FM |
4097 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
4098 | ext4_handle_dirty_metadata(handle, inode, bh); | |
ac27a0ec | 4099 | } |
617ba13b | 4100 | ext4_mark_inode_dirty(handle, inode); |
487caeef JK |
4101 | ext4_truncate_restart_trans(handle, inode, |
4102 | blocks_for_truncate(inode)); | |
ac27a0ec DK |
4103 | if (bh) { |
4104 | BUFFER_TRACE(bh, "retaking write access"); | |
617ba13b | 4105 | ext4_journal_get_write_access(handle, bh); |
ac27a0ec DK |
4106 | } |
4107 | } | |
4108 | ||
e6362609 TT |
4109 | for (p = first; p < last; p++) |
4110 | *p = 0; | |
ac27a0ec | 4111 | |
e6362609 | 4112 | ext4_free_blocks(handle, inode, 0, block_to_free, count, flags); |
ac27a0ec DK |
4113 | } |
4114 | ||
4115 | /** | |
617ba13b | 4116 | * ext4_free_data - free a list of data blocks |
ac27a0ec DK |
4117 | * @handle: handle for this transaction |
4118 | * @inode: inode we are dealing with | |
4119 | * @this_bh: indirect buffer_head which contains *@first and *@last | |
4120 | * @first: array of block numbers | |
4121 | * @last: points immediately past the end of array | |
4122 | * | |
4123 | * We are freeing all blocks refered from that array (numbers are stored as | |
4124 | * little-endian 32-bit) and updating @inode->i_blocks appropriately. | |
4125 | * | |
4126 | * We accumulate contiguous runs of blocks to free. Conveniently, if these | |
4127 | * blocks are contiguous then releasing them at one time will only affect one | |
4128 | * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't | |
4129 | * actually use a lot of journal space. | |
4130 | * | |
4131 | * @this_bh will be %NULL if @first and @last point into the inode's direct | |
4132 | * block pointers. | |
4133 | */ | |
617ba13b | 4134 | static void ext4_free_data(handle_t *handle, struct inode *inode, |
ac27a0ec DK |
4135 | struct buffer_head *this_bh, |
4136 | __le32 *first, __le32 *last) | |
4137 | { | |
617ba13b | 4138 | ext4_fsblk_t block_to_free = 0; /* Starting block # of a run */ |
ac27a0ec DK |
4139 | unsigned long count = 0; /* Number of blocks in the run */ |
4140 | __le32 *block_to_free_p = NULL; /* Pointer into inode/ind | |
4141 | corresponding to | |
4142 | block_to_free */ | |
617ba13b | 4143 | ext4_fsblk_t nr; /* Current block # */ |
ac27a0ec DK |
4144 | __le32 *p; /* Pointer into inode/ind |
4145 | for current block */ | |
4146 | int err; | |
4147 | ||
4148 | if (this_bh) { /* For indirect block */ | |
4149 | BUFFER_TRACE(this_bh, "get_write_access"); | |
617ba13b | 4150 | err = ext4_journal_get_write_access(handle, this_bh); |
ac27a0ec DK |
4151 | /* Important: if we can't update the indirect pointers |
4152 | * to the blocks, we can't free them. */ | |
4153 | if (err) | |
4154 | return; | |
4155 | } | |
4156 | ||
4157 | for (p = first; p < last; p++) { | |
4158 | nr = le32_to_cpu(*p); | |
4159 | if (nr) { | |
4160 | /* accumulate blocks to free if they're contiguous */ | |
4161 | if (count == 0) { | |
4162 | block_to_free = nr; | |
4163 | block_to_free_p = p; | |
4164 | count = 1; | |
4165 | } else if (nr == block_to_free + count) { | |
4166 | count++; | |
4167 | } else { | |
617ba13b | 4168 | ext4_clear_blocks(handle, inode, this_bh, |
ac27a0ec DK |
4169 | block_to_free, |
4170 | count, block_to_free_p, p); | |
4171 | block_to_free = nr; | |
4172 | block_to_free_p = p; | |
4173 | count = 1; | |
4174 | } | |
4175 | } | |
4176 | } | |
4177 | ||
4178 | if (count > 0) | |
617ba13b | 4179 | ext4_clear_blocks(handle, inode, this_bh, block_to_free, |
ac27a0ec DK |
4180 | count, block_to_free_p, p); |
4181 | ||
4182 | if (this_bh) { | |
0390131b | 4183 | BUFFER_TRACE(this_bh, "call ext4_handle_dirty_metadata"); |
71dc8fbc DG |
4184 | |
4185 | /* | |
4186 | * The buffer head should have an attached journal head at this | |
4187 | * point. However, if the data is corrupted and an indirect | |
4188 | * block pointed to itself, it would have been detached when | |
4189 | * the block was cleared. Check for this instead of OOPSing. | |
4190 | */ | |
e7f07968 | 4191 | if ((EXT4_JOURNAL(inode) == NULL) || bh2jh(this_bh)) |
0390131b | 4192 | ext4_handle_dirty_metadata(handle, inode, this_bh); |
71dc8fbc DG |
4193 | else |
4194 | ext4_error(inode->i_sb, __func__, | |
4195 | "circular indirect block detected, " | |
4196 | "inode=%lu, block=%llu", | |
4197 | inode->i_ino, | |
4198 | (unsigned long long) this_bh->b_blocknr); | |
ac27a0ec DK |
4199 | } |
4200 | } | |
4201 | ||
4202 | /** | |
617ba13b | 4203 | * ext4_free_branches - free an array of branches |
ac27a0ec DK |
4204 | * @handle: JBD handle for this transaction |
4205 | * @inode: inode we are dealing with | |
4206 | * @parent_bh: the buffer_head which contains *@first and *@last | |
4207 | * @first: array of block numbers | |
4208 | * @last: pointer immediately past the end of array | |
4209 | * @depth: depth of the branches to free | |
4210 | * | |
4211 | * We are freeing all blocks refered from these branches (numbers are | |
4212 | * stored as little-endian 32-bit) and updating @inode->i_blocks | |
4213 | * appropriately. | |
4214 | */ | |
617ba13b | 4215 | static void ext4_free_branches(handle_t *handle, struct inode *inode, |
ac27a0ec DK |
4216 | struct buffer_head *parent_bh, |
4217 | __le32 *first, __le32 *last, int depth) | |
4218 | { | |
617ba13b | 4219 | ext4_fsblk_t nr; |
ac27a0ec DK |
4220 | __le32 *p; |
4221 | ||
0390131b | 4222 | if (ext4_handle_is_aborted(handle)) |
ac27a0ec DK |
4223 | return; |
4224 | ||
4225 | if (depth--) { | |
4226 | struct buffer_head *bh; | |
617ba13b | 4227 | int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
ac27a0ec DK |
4228 | p = last; |
4229 | while (--p >= first) { | |
4230 | nr = le32_to_cpu(*p); | |
4231 | if (!nr) | |
4232 | continue; /* A hole */ | |
4233 | ||
4234 | /* Go read the buffer for the next level down */ | |
4235 | bh = sb_bread(inode->i_sb, nr); | |
4236 | ||
4237 | /* | |
4238 | * A read failure? Report error and clear slot | |
4239 | * (should be rare). | |
4240 | */ | |
4241 | if (!bh) { | |
617ba13b | 4242 | ext4_error(inode->i_sb, "ext4_free_branches", |
2ae02107 | 4243 | "Read failure, inode=%lu, block=%llu", |
ac27a0ec DK |
4244 | inode->i_ino, nr); |
4245 | continue; | |
4246 | } | |
4247 | ||
4248 | /* This zaps the entire block. Bottom up. */ | |
4249 | BUFFER_TRACE(bh, "free child branches"); | |
617ba13b | 4250 | ext4_free_branches(handle, inode, bh, |
af5bc92d TT |
4251 | (__le32 *) bh->b_data, |
4252 | (__le32 *) bh->b_data + addr_per_block, | |
4253 | depth); | |
ac27a0ec DK |
4254 | |
4255 | /* | |
4256 | * We've probably journalled the indirect block several | |
4257 | * times during the truncate. But it's no longer | |
4258 | * needed and we now drop it from the transaction via | |
dab291af | 4259 | * jbd2_journal_revoke(). |
ac27a0ec DK |
4260 | * |
4261 | * That's easy if it's exclusively part of this | |
4262 | * transaction. But if it's part of the committing | |
dab291af | 4263 | * transaction then jbd2_journal_forget() will simply |
ac27a0ec | 4264 | * brelse() it. That means that if the underlying |
617ba13b | 4265 | * block is reallocated in ext4_get_block(), |
ac27a0ec DK |
4266 | * unmap_underlying_metadata() will find this block |
4267 | * and will try to get rid of it. damn, damn. | |
4268 | * | |
4269 | * If this block has already been committed to the | |
4270 | * journal, a revoke record will be written. And | |
4271 | * revoke records must be emitted *before* clearing | |
4272 | * this block's bit in the bitmaps. | |
4273 | */ | |
617ba13b | 4274 | ext4_forget(handle, 1, inode, bh, bh->b_blocknr); |
ac27a0ec DK |
4275 | |
4276 | /* | |
4277 | * Everything below this this pointer has been | |
4278 | * released. Now let this top-of-subtree go. | |
4279 | * | |
4280 | * We want the freeing of this indirect block to be | |
4281 | * atomic in the journal with the updating of the | |
4282 | * bitmap block which owns it. So make some room in | |
4283 | * the journal. | |
4284 | * | |
4285 | * We zero the parent pointer *after* freeing its | |
4286 | * pointee in the bitmaps, so if extend_transaction() | |
4287 | * for some reason fails to put the bitmap changes and | |
4288 | * the release into the same transaction, recovery | |
4289 | * will merely complain about releasing a free block, | |
4290 | * rather than leaking blocks. | |
4291 | */ | |
0390131b | 4292 | if (ext4_handle_is_aborted(handle)) |
ac27a0ec DK |
4293 | return; |
4294 | if (try_to_extend_transaction(handle, inode)) { | |
617ba13b | 4295 | ext4_mark_inode_dirty(handle, inode); |
487caeef JK |
4296 | ext4_truncate_restart_trans(handle, inode, |
4297 | blocks_for_truncate(inode)); | |
ac27a0ec DK |
4298 | } |
4299 | ||
e6362609 TT |
4300 | ext4_free_blocks(handle, inode, 0, nr, 1, |
4301 | EXT4_FREE_BLOCKS_METADATA); | |
ac27a0ec DK |
4302 | |
4303 | if (parent_bh) { | |
4304 | /* | |
4305 | * The block which we have just freed is | |
4306 | * pointed to by an indirect block: journal it | |
4307 | */ | |
4308 | BUFFER_TRACE(parent_bh, "get_write_access"); | |
617ba13b | 4309 | if (!ext4_journal_get_write_access(handle, |
ac27a0ec DK |
4310 | parent_bh)){ |
4311 | *p = 0; | |
4312 | BUFFER_TRACE(parent_bh, | |
0390131b FM |
4313 | "call ext4_handle_dirty_metadata"); |
4314 | ext4_handle_dirty_metadata(handle, | |
4315 | inode, | |
4316 | parent_bh); | |
ac27a0ec DK |
4317 | } |
4318 | } | |
4319 | } | |
4320 | } else { | |
4321 | /* We have reached the bottom of the tree. */ | |
4322 | BUFFER_TRACE(parent_bh, "free data blocks"); | |
617ba13b | 4323 | ext4_free_data(handle, inode, parent_bh, first, last); |
ac27a0ec DK |
4324 | } |
4325 | } | |
4326 | ||
91ef4caf DG |
4327 | int ext4_can_truncate(struct inode *inode) |
4328 | { | |
4329 | if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) | |
4330 | return 0; | |
4331 | if (S_ISREG(inode->i_mode)) | |
4332 | return 1; | |
4333 | if (S_ISDIR(inode->i_mode)) | |
4334 | return 1; | |
4335 | if (S_ISLNK(inode->i_mode)) | |
4336 | return !ext4_inode_is_fast_symlink(inode); | |
4337 | return 0; | |
4338 | } | |
4339 | ||
ac27a0ec | 4340 | /* |
617ba13b | 4341 | * ext4_truncate() |
ac27a0ec | 4342 | * |
617ba13b MC |
4343 | * We block out ext4_get_block() block instantiations across the entire |
4344 | * transaction, and VFS/VM ensures that ext4_truncate() cannot run | |
ac27a0ec DK |
4345 | * simultaneously on behalf of the same inode. |
4346 | * | |
4347 | * As we work through the truncate and commmit bits of it to the journal there | |
4348 | * is one core, guiding principle: the file's tree must always be consistent on | |
4349 | * disk. We must be able to restart the truncate after a crash. | |
4350 | * | |
4351 | * The file's tree may be transiently inconsistent in memory (although it | |
4352 | * probably isn't), but whenever we close off and commit a journal transaction, | |
4353 | * the contents of (the filesystem + the journal) must be consistent and | |
4354 | * restartable. It's pretty simple, really: bottom up, right to left (although | |
4355 | * left-to-right works OK too). | |
4356 | * | |
4357 | * Note that at recovery time, journal replay occurs *before* the restart of | |
4358 | * truncate against the orphan inode list. | |
4359 | * | |
4360 | * The committed inode has the new, desired i_size (which is the same as | |
617ba13b | 4361 | * i_disksize in this case). After a crash, ext4_orphan_cleanup() will see |
ac27a0ec | 4362 | * that this inode's truncate did not complete and it will again call |
617ba13b MC |
4363 | * ext4_truncate() to have another go. So there will be instantiated blocks |
4364 | * to the right of the truncation point in a crashed ext4 filesystem. But | |
ac27a0ec | 4365 | * that's fine - as long as they are linked from the inode, the post-crash |
617ba13b | 4366 | * ext4_truncate() run will find them and release them. |
ac27a0ec | 4367 | */ |
617ba13b | 4368 | void ext4_truncate(struct inode *inode) |
ac27a0ec DK |
4369 | { |
4370 | handle_t *handle; | |
617ba13b | 4371 | struct ext4_inode_info *ei = EXT4_I(inode); |
ac27a0ec | 4372 | __le32 *i_data = ei->i_data; |
617ba13b | 4373 | int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
ac27a0ec | 4374 | struct address_space *mapping = inode->i_mapping; |
725d26d3 | 4375 | ext4_lblk_t offsets[4]; |
ac27a0ec DK |
4376 | Indirect chain[4]; |
4377 | Indirect *partial; | |
4378 | __le32 nr = 0; | |
4379 | int n; | |
725d26d3 | 4380 | ext4_lblk_t last_block; |
ac27a0ec | 4381 | unsigned blocksize = inode->i_sb->s_blocksize; |
ac27a0ec | 4382 | |
91ef4caf | 4383 | if (!ext4_can_truncate(inode)) |
ac27a0ec DK |
4384 | return; |
4385 | ||
5534fb5b | 4386 | if (inode->i_size == 0 && !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC)) |
7d8f9f7d TT |
4387 | ei->i_state |= EXT4_STATE_DA_ALLOC_CLOSE; |
4388 | ||
1d03ec98 | 4389 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { |
cf108bca | 4390 | ext4_ext_truncate(inode); |
1d03ec98 AK |
4391 | return; |
4392 | } | |
a86c6181 | 4393 | |
ac27a0ec | 4394 | handle = start_transaction(inode); |
cf108bca | 4395 | if (IS_ERR(handle)) |
ac27a0ec | 4396 | return; /* AKPM: return what? */ |
ac27a0ec DK |
4397 | |
4398 | last_block = (inode->i_size + blocksize-1) | |
617ba13b | 4399 | >> EXT4_BLOCK_SIZE_BITS(inode->i_sb); |
ac27a0ec | 4400 | |
cf108bca JK |
4401 | if (inode->i_size & (blocksize - 1)) |
4402 | if (ext4_block_truncate_page(handle, mapping, inode->i_size)) | |
4403 | goto out_stop; | |
ac27a0ec | 4404 | |
617ba13b | 4405 | n = ext4_block_to_path(inode, last_block, offsets, NULL); |
ac27a0ec DK |
4406 | if (n == 0) |
4407 | goto out_stop; /* error */ | |
4408 | ||
4409 | /* | |
4410 | * OK. This truncate is going to happen. We add the inode to the | |
4411 | * orphan list, so that if this truncate spans multiple transactions, | |
4412 | * and we crash, we will resume the truncate when the filesystem | |
4413 | * recovers. It also marks the inode dirty, to catch the new size. | |
4414 | * | |
4415 | * Implication: the file must always be in a sane, consistent | |
4416 | * truncatable state while each transaction commits. | |
4417 | */ | |
617ba13b | 4418 | if (ext4_orphan_add(handle, inode)) |
ac27a0ec DK |
4419 | goto out_stop; |
4420 | ||
632eaeab MC |
4421 | /* |
4422 | * From here we block out all ext4_get_block() callers who want to | |
4423 | * modify the block allocation tree. | |
4424 | */ | |
4425 | down_write(&ei->i_data_sem); | |
b4df2030 | 4426 | |
c2ea3fde | 4427 | ext4_discard_preallocations(inode); |
b4df2030 | 4428 | |
ac27a0ec DK |
4429 | /* |
4430 | * The orphan list entry will now protect us from any crash which | |
4431 | * occurs before the truncate completes, so it is now safe to propagate | |
4432 | * the new, shorter inode size (held for now in i_size) into the | |
4433 | * on-disk inode. We do this via i_disksize, which is the value which | |
617ba13b | 4434 | * ext4 *really* writes onto the disk inode. |
ac27a0ec DK |
4435 | */ |
4436 | ei->i_disksize = inode->i_size; | |
4437 | ||
ac27a0ec | 4438 | if (n == 1) { /* direct blocks */ |
617ba13b MC |
4439 | ext4_free_data(handle, inode, NULL, i_data+offsets[0], |
4440 | i_data + EXT4_NDIR_BLOCKS); | |
ac27a0ec DK |
4441 | goto do_indirects; |
4442 | } | |
4443 | ||
617ba13b | 4444 | partial = ext4_find_shared(inode, n, offsets, chain, &nr); |
ac27a0ec DK |
4445 | /* Kill the top of shared branch (not detached) */ |
4446 | if (nr) { | |
4447 | if (partial == chain) { | |
4448 | /* Shared branch grows from the inode */ | |
617ba13b | 4449 | ext4_free_branches(handle, inode, NULL, |
ac27a0ec DK |
4450 | &nr, &nr+1, (chain+n-1) - partial); |
4451 | *partial->p = 0; | |
4452 | /* | |
4453 | * We mark the inode dirty prior to restart, | |
4454 | * and prior to stop. No need for it here. | |
4455 | */ | |
4456 | } else { | |
4457 | /* Shared branch grows from an indirect block */ | |
4458 | BUFFER_TRACE(partial->bh, "get_write_access"); | |
617ba13b | 4459 | ext4_free_branches(handle, inode, partial->bh, |
ac27a0ec DK |
4460 | partial->p, |
4461 | partial->p+1, (chain+n-1) - partial); | |
4462 | } | |
4463 | } | |
4464 | /* Clear the ends of indirect blocks on the shared branch */ | |
4465 | while (partial > chain) { | |
617ba13b | 4466 | ext4_free_branches(handle, inode, partial->bh, partial->p + 1, |
ac27a0ec DK |
4467 | (__le32*)partial->bh->b_data+addr_per_block, |
4468 | (chain+n-1) - partial); | |
4469 | BUFFER_TRACE(partial->bh, "call brelse"); | |
de9a55b8 | 4470 | brelse(partial->bh); |
ac27a0ec DK |
4471 | partial--; |
4472 | } | |
4473 | do_indirects: | |
4474 | /* Kill the remaining (whole) subtrees */ | |
4475 | switch (offsets[0]) { | |
4476 | default: | |
617ba13b | 4477 | nr = i_data[EXT4_IND_BLOCK]; |
ac27a0ec | 4478 | if (nr) { |
617ba13b MC |
4479 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 1); |
4480 | i_data[EXT4_IND_BLOCK] = 0; | |
ac27a0ec | 4481 | } |
617ba13b MC |
4482 | case EXT4_IND_BLOCK: |
4483 | nr = i_data[EXT4_DIND_BLOCK]; | |
ac27a0ec | 4484 | if (nr) { |
617ba13b MC |
4485 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 2); |
4486 | i_data[EXT4_DIND_BLOCK] = 0; | |
ac27a0ec | 4487 | } |
617ba13b MC |
4488 | case EXT4_DIND_BLOCK: |
4489 | nr = i_data[EXT4_TIND_BLOCK]; | |
ac27a0ec | 4490 | if (nr) { |
617ba13b MC |
4491 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 3); |
4492 | i_data[EXT4_TIND_BLOCK] = 0; | |
ac27a0ec | 4493 | } |
617ba13b | 4494 | case EXT4_TIND_BLOCK: |
ac27a0ec DK |
4495 | ; |
4496 | } | |
4497 | ||
0e855ac8 | 4498 | up_write(&ei->i_data_sem); |
ef7f3835 | 4499 | inode->i_mtime = inode->i_ctime = ext4_current_time(inode); |
617ba13b | 4500 | ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
4501 | |
4502 | /* | |
4503 | * In a multi-transaction truncate, we only make the final transaction | |
4504 | * synchronous | |
4505 | */ | |
4506 | if (IS_SYNC(inode)) | |
0390131b | 4507 | ext4_handle_sync(handle); |
ac27a0ec DK |
4508 | out_stop: |
4509 | /* | |
4510 | * If this was a simple ftruncate(), and the file will remain alive | |
4511 | * then we need to clear up the orphan record which we created above. | |
4512 | * However, if this was a real unlink then we were called by | |
617ba13b | 4513 | * ext4_delete_inode(), and we allow that function to clean up the |
ac27a0ec DK |
4514 | * orphan info for us. |
4515 | */ | |
4516 | if (inode->i_nlink) | |
617ba13b | 4517 | ext4_orphan_del(handle, inode); |
ac27a0ec | 4518 | |
617ba13b | 4519 | ext4_journal_stop(handle); |
ac27a0ec DK |
4520 | } |
4521 | ||
ac27a0ec | 4522 | /* |
617ba13b | 4523 | * ext4_get_inode_loc returns with an extra refcount against the inode's |
ac27a0ec DK |
4524 | * underlying buffer_head on success. If 'in_mem' is true, we have all |
4525 | * data in memory that is needed to recreate the on-disk version of this | |
4526 | * inode. | |
4527 | */ | |
617ba13b MC |
4528 | static int __ext4_get_inode_loc(struct inode *inode, |
4529 | struct ext4_iloc *iloc, int in_mem) | |
ac27a0ec | 4530 | { |
240799cd TT |
4531 | struct ext4_group_desc *gdp; |
4532 | struct buffer_head *bh; | |
4533 | struct super_block *sb = inode->i_sb; | |
4534 | ext4_fsblk_t block; | |
4535 | int inodes_per_block, inode_offset; | |
4536 | ||
3a06d778 | 4537 | iloc->bh = NULL; |
240799cd TT |
4538 | if (!ext4_valid_inum(sb, inode->i_ino)) |
4539 | return -EIO; | |
ac27a0ec | 4540 | |
240799cd TT |
4541 | iloc->block_group = (inode->i_ino - 1) / EXT4_INODES_PER_GROUP(sb); |
4542 | gdp = ext4_get_group_desc(sb, iloc->block_group, NULL); | |
4543 | if (!gdp) | |
ac27a0ec DK |
4544 | return -EIO; |
4545 | ||
240799cd TT |
4546 | /* |
4547 | * Figure out the offset within the block group inode table | |
4548 | */ | |
4549 | inodes_per_block = (EXT4_BLOCK_SIZE(sb) / EXT4_INODE_SIZE(sb)); | |
4550 | inode_offset = ((inode->i_ino - 1) % | |
4551 | EXT4_INODES_PER_GROUP(sb)); | |
4552 | block = ext4_inode_table(sb, gdp) + (inode_offset / inodes_per_block); | |
4553 | iloc->offset = (inode_offset % inodes_per_block) * EXT4_INODE_SIZE(sb); | |
4554 | ||
4555 | bh = sb_getblk(sb, block); | |
ac27a0ec | 4556 | if (!bh) { |
240799cd TT |
4557 | ext4_error(sb, "ext4_get_inode_loc", "unable to read " |
4558 | "inode block - inode=%lu, block=%llu", | |
4559 | inode->i_ino, block); | |
ac27a0ec DK |
4560 | return -EIO; |
4561 | } | |
4562 | if (!buffer_uptodate(bh)) { | |
4563 | lock_buffer(bh); | |
9c83a923 HK |
4564 | |
4565 | /* | |
4566 | * If the buffer has the write error flag, we have failed | |
4567 | * to write out another inode in the same block. In this | |
4568 | * case, we don't have to read the block because we may | |
4569 | * read the old inode data successfully. | |
4570 | */ | |
4571 | if (buffer_write_io_error(bh) && !buffer_uptodate(bh)) | |
4572 | set_buffer_uptodate(bh); | |
4573 | ||
ac27a0ec DK |
4574 | if (buffer_uptodate(bh)) { |
4575 | /* someone brought it uptodate while we waited */ | |
4576 | unlock_buffer(bh); | |
4577 | goto has_buffer; | |
4578 | } | |
4579 | ||
4580 | /* | |
4581 | * If we have all information of the inode in memory and this | |
4582 | * is the only valid inode in the block, we need not read the | |
4583 | * block. | |
4584 | */ | |
4585 | if (in_mem) { | |
4586 | struct buffer_head *bitmap_bh; | |
240799cd | 4587 | int i, start; |
ac27a0ec | 4588 | |
240799cd | 4589 | start = inode_offset & ~(inodes_per_block - 1); |
ac27a0ec | 4590 | |
240799cd TT |
4591 | /* Is the inode bitmap in cache? */ |
4592 | bitmap_bh = sb_getblk(sb, ext4_inode_bitmap(sb, gdp)); | |
ac27a0ec DK |
4593 | if (!bitmap_bh) |
4594 | goto make_io; | |
4595 | ||
4596 | /* | |
4597 | * If the inode bitmap isn't in cache then the | |
4598 | * optimisation may end up performing two reads instead | |
4599 | * of one, so skip it. | |
4600 | */ | |
4601 | if (!buffer_uptodate(bitmap_bh)) { | |
4602 | brelse(bitmap_bh); | |
4603 | goto make_io; | |
4604 | } | |
240799cd | 4605 | for (i = start; i < start + inodes_per_block; i++) { |
ac27a0ec DK |
4606 | if (i == inode_offset) |
4607 | continue; | |
617ba13b | 4608 | if (ext4_test_bit(i, bitmap_bh->b_data)) |
ac27a0ec DK |
4609 | break; |
4610 | } | |
4611 | brelse(bitmap_bh); | |
240799cd | 4612 | if (i == start + inodes_per_block) { |
ac27a0ec DK |
4613 | /* all other inodes are free, so skip I/O */ |
4614 | memset(bh->b_data, 0, bh->b_size); | |
4615 | set_buffer_uptodate(bh); | |
4616 | unlock_buffer(bh); | |
4617 | goto has_buffer; | |
4618 | } | |
4619 | } | |
4620 | ||
4621 | make_io: | |
240799cd TT |
4622 | /* |
4623 | * If we need to do any I/O, try to pre-readahead extra | |
4624 | * blocks from the inode table. | |
4625 | */ | |
4626 | if (EXT4_SB(sb)->s_inode_readahead_blks) { | |
4627 | ext4_fsblk_t b, end, table; | |
4628 | unsigned num; | |
4629 | ||
4630 | table = ext4_inode_table(sb, gdp); | |
b713a5ec | 4631 | /* s_inode_readahead_blks is always a power of 2 */ |
240799cd TT |
4632 | b = block & ~(EXT4_SB(sb)->s_inode_readahead_blks-1); |
4633 | if (table > b) | |
4634 | b = table; | |
4635 | end = b + EXT4_SB(sb)->s_inode_readahead_blks; | |
4636 | num = EXT4_INODES_PER_GROUP(sb); | |
4637 | if (EXT4_HAS_RO_COMPAT_FEATURE(sb, | |
4638 | EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) | |
560671a0 | 4639 | num -= ext4_itable_unused_count(sb, gdp); |
240799cd TT |
4640 | table += num / inodes_per_block; |
4641 | if (end > table) | |
4642 | end = table; | |
4643 | while (b <= end) | |
4644 | sb_breadahead(sb, b++); | |
4645 | } | |
4646 | ||
ac27a0ec DK |
4647 | /* |
4648 | * There are other valid inodes in the buffer, this inode | |
4649 | * has in-inode xattrs, or we don't have this inode in memory. | |
4650 | * Read the block from disk. | |
4651 | */ | |
4652 | get_bh(bh); | |
4653 | bh->b_end_io = end_buffer_read_sync; | |
4654 | submit_bh(READ_META, bh); | |
4655 | wait_on_buffer(bh); | |
4656 | if (!buffer_uptodate(bh)) { | |
240799cd TT |
4657 | ext4_error(sb, __func__, |
4658 | "unable to read inode block - inode=%lu, " | |
4659 | "block=%llu", inode->i_ino, block); | |
ac27a0ec DK |
4660 | brelse(bh); |
4661 | return -EIO; | |
4662 | } | |
4663 | } | |
4664 | has_buffer: | |
4665 | iloc->bh = bh; | |
4666 | return 0; | |
4667 | } | |
4668 | ||
617ba13b | 4669 | int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc) |
ac27a0ec DK |
4670 | { |
4671 | /* We have all inode data except xattrs in memory here. */ | |
617ba13b MC |
4672 | return __ext4_get_inode_loc(inode, iloc, |
4673 | !(EXT4_I(inode)->i_state & EXT4_STATE_XATTR)); | |
ac27a0ec DK |
4674 | } |
4675 | ||
617ba13b | 4676 | void ext4_set_inode_flags(struct inode *inode) |
ac27a0ec | 4677 | { |
617ba13b | 4678 | unsigned int flags = EXT4_I(inode)->i_flags; |
ac27a0ec DK |
4679 | |
4680 | inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); | |
617ba13b | 4681 | if (flags & EXT4_SYNC_FL) |
ac27a0ec | 4682 | inode->i_flags |= S_SYNC; |
617ba13b | 4683 | if (flags & EXT4_APPEND_FL) |
ac27a0ec | 4684 | inode->i_flags |= S_APPEND; |
617ba13b | 4685 | if (flags & EXT4_IMMUTABLE_FL) |
ac27a0ec | 4686 | inode->i_flags |= S_IMMUTABLE; |
617ba13b | 4687 | if (flags & EXT4_NOATIME_FL) |
ac27a0ec | 4688 | inode->i_flags |= S_NOATIME; |
617ba13b | 4689 | if (flags & EXT4_DIRSYNC_FL) |
ac27a0ec DK |
4690 | inode->i_flags |= S_DIRSYNC; |
4691 | } | |
4692 | ||
ff9ddf7e JK |
4693 | /* Propagate flags from i_flags to EXT4_I(inode)->i_flags */ |
4694 | void ext4_get_inode_flags(struct ext4_inode_info *ei) | |
4695 | { | |
4696 | unsigned int flags = ei->vfs_inode.i_flags; | |
4697 | ||
4698 | ei->i_flags &= ~(EXT4_SYNC_FL|EXT4_APPEND_FL| | |
4699 | EXT4_IMMUTABLE_FL|EXT4_NOATIME_FL|EXT4_DIRSYNC_FL); | |
4700 | if (flags & S_SYNC) | |
4701 | ei->i_flags |= EXT4_SYNC_FL; | |
4702 | if (flags & S_APPEND) | |
4703 | ei->i_flags |= EXT4_APPEND_FL; | |
4704 | if (flags & S_IMMUTABLE) | |
4705 | ei->i_flags |= EXT4_IMMUTABLE_FL; | |
4706 | if (flags & S_NOATIME) | |
4707 | ei->i_flags |= EXT4_NOATIME_FL; | |
4708 | if (flags & S_DIRSYNC) | |
4709 | ei->i_flags |= EXT4_DIRSYNC_FL; | |
4710 | } | |
de9a55b8 | 4711 | |
0fc1b451 | 4712 | static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode, |
de9a55b8 | 4713 | struct ext4_inode_info *ei) |
0fc1b451 AK |
4714 | { |
4715 | blkcnt_t i_blocks ; | |
8180a562 AK |
4716 | struct inode *inode = &(ei->vfs_inode); |
4717 | struct super_block *sb = inode->i_sb; | |
0fc1b451 AK |
4718 | |
4719 | if (EXT4_HAS_RO_COMPAT_FEATURE(sb, | |
4720 | EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) { | |
4721 | /* we are using combined 48 bit field */ | |
4722 | i_blocks = ((u64)le16_to_cpu(raw_inode->i_blocks_high)) << 32 | | |
4723 | le32_to_cpu(raw_inode->i_blocks_lo); | |
8180a562 AK |
4724 | if (ei->i_flags & EXT4_HUGE_FILE_FL) { |
4725 | /* i_blocks represent file system block size */ | |
4726 | return i_blocks << (inode->i_blkbits - 9); | |
4727 | } else { | |
4728 | return i_blocks; | |
4729 | } | |
0fc1b451 AK |
4730 | } else { |
4731 | return le32_to_cpu(raw_inode->i_blocks_lo); | |
4732 | } | |
4733 | } | |
ff9ddf7e | 4734 | |
1d1fe1ee | 4735 | struct inode *ext4_iget(struct super_block *sb, unsigned long ino) |
ac27a0ec | 4736 | { |
617ba13b MC |
4737 | struct ext4_iloc iloc; |
4738 | struct ext4_inode *raw_inode; | |
1d1fe1ee | 4739 | struct ext4_inode_info *ei; |
1d1fe1ee DH |
4740 | struct inode *inode; |
4741 | long ret; | |
ac27a0ec DK |
4742 | int block; |
4743 | ||
1d1fe1ee DH |
4744 | inode = iget_locked(sb, ino); |
4745 | if (!inode) | |
4746 | return ERR_PTR(-ENOMEM); | |
4747 | if (!(inode->i_state & I_NEW)) | |
4748 | return inode; | |
4749 | ||
4750 | ei = EXT4_I(inode); | |
567f3e9a | 4751 | iloc.bh = 0; |
ac27a0ec | 4752 | |
1d1fe1ee DH |
4753 | ret = __ext4_get_inode_loc(inode, &iloc, 0); |
4754 | if (ret < 0) | |
ac27a0ec | 4755 | goto bad_inode; |
617ba13b | 4756 | raw_inode = ext4_raw_inode(&iloc); |
ac27a0ec DK |
4757 | inode->i_mode = le16_to_cpu(raw_inode->i_mode); |
4758 | inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low); | |
4759 | inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low); | |
af5bc92d | 4760 | if (!(test_opt(inode->i_sb, NO_UID32))) { |
ac27a0ec DK |
4761 | inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16; |
4762 | inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16; | |
4763 | } | |
4764 | inode->i_nlink = le16_to_cpu(raw_inode->i_links_count); | |
ac27a0ec DK |
4765 | |
4766 | ei->i_state = 0; | |
4767 | ei->i_dir_start_lookup = 0; | |
4768 | ei->i_dtime = le32_to_cpu(raw_inode->i_dtime); | |
4769 | /* We now have enough fields to check if the inode was active or not. | |
4770 | * This is needed because nfsd might try to access dead inodes | |
4771 | * the test is that same one that e2fsck uses | |
4772 | * NeilBrown 1999oct15 | |
4773 | */ | |
4774 | if (inode->i_nlink == 0) { | |
4775 | if (inode->i_mode == 0 || | |
617ba13b | 4776 | !(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) { |
ac27a0ec | 4777 | /* this inode is deleted */ |
1d1fe1ee | 4778 | ret = -ESTALE; |
ac27a0ec DK |
4779 | goto bad_inode; |
4780 | } | |
4781 | /* The only unlinked inodes we let through here have | |
4782 | * valid i_mode and are being read by the orphan | |
4783 | * recovery code: that's fine, we're about to complete | |
4784 | * the process of deleting those. */ | |
4785 | } | |
ac27a0ec | 4786 | ei->i_flags = le32_to_cpu(raw_inode->i_flags); |
0fc1b451 | 4787 | inode->i_blocks = ext4_inode_blocks(raw_inode, ei); |
7973c0c1 | 4788 | ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl_lo); |
a9e81742 | 4789 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) |
a1ddeb7e BP |
4790 | ei->i_file_acl |= |
4791 | ((__u64)le16_to_cpu(raw_inode->i_file_acl_high)) << 32; | |
a48380f7 | 4792 | inode->i_size = ext4_isize(raw_inode); |
ac27a0ec DK |
4793 | ei->i_disksize = inode->i_size; |
4794 | inode->i_generation = le32_to_cpu(raw_inode->i_generation); | |
4795 | ei->i_block_group = iloc.block_group; | |
a4912123 | 4796 | ei->i_last_alloc_group = ~0; |
ac27a0ec DK |
4797 | /* |
4798 | * NOTE! The in-memory inode i_data array is in little-endian order | |
4799 | * even on big-endian machines: we do NOT byteswap the block numbers! | |
4800 | */ | |
617ba13b | 4801 | for (block = 0; block < EXT4_N_BLOCKS; block++) |
ac27a0ec DK |
4802 | ei->i_data[block] = raw_inode->i_block[block]; |
4803 | INIT_LIST_HEAD(&ei->i_orphan); | |
4804 | ||
0040d987 | 4805 | if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) { |
ac27a0ec | 4806 | ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize); |
617ba13b | 4807 | if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize > |
e5d2861f | 4808 | EXT4_INODE_SIZE(inode->i_sb)) { |
1d1fe1ee | 4809 | ret = -EIO; |
ac27a0ec | 4810 | goto bad_inode; |
e5d2861f | 4811 | } |
ac27a0ec DK |
4812 | if (ei->i_extra_isize == 0) { |
4813 | /* The extra space is currently unused. Use it. */ | |
617ba13b MC |
4814 | ei->i_extra_isize = sizeof(struct ext4_inode) - |
4815 | EXT4_GOOD_OLD_INODE_SIZE; | |
ac27a0ec DK |
4816 | } else { |
4817 | __le32 *magic = (void *)raw_inode + | |
617ba13b | 4818 | EXT4_GOOD_OLD_INODE_SIZE + |
ac27a0ec | 4819 | ei->i_extra_isize; |
617ba13b | 4820 | if (*magic == cpu_to_le32(EXT4_XATTR_MAGIC)) |
de9a55b8 | 4821 | ei->i_state |= EXT4_STATE_XATTR; |
ac27a0ec DK |
4822 | } |
4823 | } else | |
4824 | ei->i_extra_isize = 0; | |
4825 | ||
ef7f3835 KS |
4826 | EXT4_INODE_GET_XTIME(i_ctime, inode, raw_inode); |
4827 | EXT4_INODE_GET_XTIME(i_mtime, inode, raw_inode); | |
4828 | EXT4_INODE_GET_XTIME(i_atime, inode, raw_inode); | |
4829 | EXT4_EINODE_GET_XTIME(i_crtime, ei, raw_inode); | |
4830 | ||
25ec56b5 JNC |
4831 | inode->i_version = le32_to_cpu(raw_inode->i_disk_version); |
4832 | if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) { | |
4833 | if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi)) | |
4834 | inode->i_version |= | |
4835 | (__u64)(le32_to_cpu(raw_inode->i_version_hi)) << 32; | |
4836 | } | |
4837 | ||
c4b5a614 | 4838 | ret = 0; |
485c26ec | 4839 | if (ei->i_file_acl && |
1032988c | 4840 | !ext4_data_block_valid(EXT4_SB(sb), ei->i_file_acl, 1)) { |
485c26ec TT |
4841 | ext4_error(sb, __func__, |
4842 | "bad extended attribute block %llu in inode #%lu", | |
4843 | ei->i_file_acl, inode->i_ino); | |
4844 | ret = -EIO; | |
4845 | goto bad_inode; | |
4846 | } else if (ei->i_flags & EXT4_EXTENTS_FL) { | |
c4b5a614 TT |
4847 | if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || |
4848 | (S_ISLNK(inode->i_mode) && | |
4849 | !ext4_inode_is_fast_symlink(inode))) | |
4850 | /* Validate extent which is part of inode */ | |
4851 | ret = ext4_ext_check_inode(inode); | |
de9a55b8 | 4852 | } else if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || |
fe2c8191 TN |
4853 | (S_ISLNK(inode->i_mode) && |
4854 | !ext4_inode_is_fast_symlink(inode))) { | |
de9a55b8 | 4855 | /* Validate block references which are part of inode */ |
fe2c8191 TN |
4856 | ret = ext4_check_inode_blockref(inode); |
4857 | } | |
567f3e9a | 4858 | if (ret) |
de9a55b8 | 4859 | goto bad_inode; |
7a262f7c | 4860 | |
ac27a0ec | 4861 | if (S_ISREG(inode->i_mode)) { |
617ba13b MC |
4862 | inode->i_op = &ext4_file_inode_operations; |
4863 | inode->i_fop = &ext4_file_operations; | |
4864 | ext4_set_aops(inode); | |
ac27a0ec | 4865 | } else if (S_ISDIR(inode->i_mode)) { |
617ba13b MC |
4866 | inode->i_op = &ext4_dir_inode_operations; |
4867 | inode->i_fop = &ext4_dir_operations; | |
ac27a0ec | 4868 | } else if (S_ISLNK(inode->i_mode)) { |
e83c1397 | 4869 | if (ext4_inode_is_fast_symlink(inode)) { |
617ba13b | 4870 | inode->i_op = &ext4_fast_symlink_inode_operations; |
e83c1397 DG |
4871 | nd_terminate_link(ei->i_data, inode->i_size, |
4872 | sizeof(ei->i_data) - 1); | |
4873 | } else { | |
617ba13b MC |
4874 | inode->i_op = &ext4_symlink_inode_operations; |
4875 | ext4_set_aops(inode); | |
ac27a0ec | 4876 | } |
563bdd61 TT |
4877 | } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || |
4878 | S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { | |
617ba13b | 4879 | inode->i_op = &ext4_special_inode_operations; |
ac27a0ec DK |
4880 | if (raw_inode->i_block[0]) |
4881 | init_special_inode(inode, inode->i_mode, | |
4882 | old_decode_dev(le32_to_cpu(raw_inode->i_block[0]))); | |
4883 | else | |
4884 | init_special_inode(inode, inode->i_mode, | |
4885 | new_decode_dev(le32_to_cpu(raw_inode->i_block[1]))); | |
563bdd61 | 4886 | } else { |
563bdd61 | 4887 | ret = -EIO; |
de9a55b8 | 4888 | ext4_error(inode->i_sb, __func__, |
563bdd61 TT |
4889 | "bogus i_mode (%o) for inode=%lu", |
4890 | inode->i_mode, inode->i_ino); | |
4891 | goto bad_inode; | |
ac27a0ec | 4892 | } |
af5bc92d | 4893 | brelse(iloc.bh); |
617ba13b | 4894 | ext4_set_inode_flags(inode); |
1d1fe1ee DH |
4895 | unlock_new_inode(inode); |
4896 | return inode; | |
ac27a0ec DK |
4897 | |
4898 | bad_inode: | |
567f3e9a | 4899 | brelse(iloc.bh); |
1d1fe1ee DH |
4900 | iget_failed(inode); |
4901 | return ERR_PTR(ret); | |
ac27a0ec DK |
4902 | } |
4903 | ||
0fc1b451 AK |
4904 | static int ext4_inode_blocks_set(handle_t *handle, |
4905 | struct ext4_inode *raw_inode, | |
4906 | struct ext4_inode_info *ei) | |
4907 | { | |
4908 | struct inode *inode = &(ei->vfs_inode); | |
4909 | u64 i_blocks = inode->i_blocks; | |
4910 | struct super_block *sb = inode->i_sb; | |
0fc1b451 AK |
4911 | |
4912 | if (i_blocks <= ~0U) { | |
4913 | /* | |
4914 | * i_blocks can be represnted in a 32 bit variable | |
4915 | * as multiple of 512 bytes | |
4916 | */ | |
8180a562 | 4917 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); |
0fc1b451 | 4918 | raw_inode->i_blocks_high = 0; |
8180a562 | 4919 | ei->i_flags &= ~EXT4_HUGE_FILE_FL; |
f287a1a5 TT |
4920 | return 0; |
4921 | } | |
4922 | if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) | |
4923 | return -EFBIG; | |
4924 | ||
4925 | if (i_blocks <= 0xffffffffffffULL) { | |
0fc1b451 AK |
4926 | /* |
4927 | * i_blocks can be represented in a 48 bit variable | |
4928 | * as multiple of 512 bytes | |
4929 | */ | |
8180a562 | 4930 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); |
0fc1b451 | 4931 | raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32); |
8180a562 | 4932 | ei->i_flags &= ~EXT4_HUGE_FILE_FL; |
0fc1b451 | 4933 | } else { |
8180a562 AK |
4934 | ei->i_flags |= EXT4_HUGE_FILE_FL; |
4935 | /* i_block is stored in file system block size */ | |
4936 | i_blocks = i_blocks >> (inode->i_blkbits - 9); | |
4937 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); | |
4938 | raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32); | |
0fc1b451 | 4939 | } |
f287a1a5 | 4940 | return 0; |
0fc1b451 AK |
4941 | } |
4942 | ||
ac27a0ec DK |
4943 | /* |
4944 | * Post the struct inode info into an on-disk inode location in the | |
4945 | * buffer-cache. This gobbles the caller's reference to the | |
4946 | * buffer_head in the inode location struct. | |
4947 | * | |
4948 | * The caller must have write access to iloc->bh. | |
4949 | */ | |
617ba13b | 4950 | static int ext4_do_update_inode(handle_t *handle, |
ac27a0ec | 4951 | struct inode *inode, |
830156c7 | 4952 | struct ext4_iloc *iloc) |
ac27a0ec | 4953 | { |
617ba13b MC |
4954 | struct ext4_inode *raw_inode = ext4_raw_inode(iloc); |
4955 | struct ext4_inode_info *ei = EXT4_I(inode); | |
ac27a0ec DK |
4956 | struct buffer_head *bh = iloc->bh; |
4957 | int err = 0, rc, block; | |
4958 | ||
4959 | /* For fields not not tracking in the in-memory inode, | |
4960 | * initialise them to zero for new inodes. */ | |
617ba13b MC |
4961 | if (ei->i_state & EXT4_STATE_NEW) |
4962 | memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); | |
ac27a0ec | 4963 | |
ff9ddf7e | 4964 | ext4_get_inode_flags(ei); |
ac27a0ec | 4965 | raw_inode->i_mode = cpu_to_le16(inode->i_mode); |
af5bc92d | 4966 | if (!(test_opt(inode->i_sb, NO_UID32))) { |
ac27a0ec DK |
4967 | raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid)); |
4968 | raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid)); | |
4969 | /* | |
4970 | * Fix up interoperability with old kernels. Otherwise, old inodes get | |
4971 | * re-used with the upper 16 bits of the uid/gid intact | |
4972 | */ | |
af5bc92d | 4973 | if (!ei->i_dtime) { |
ac27a0ec DK |
4974 | raw_inode->i_uid_high = |
4975 | cpu_to_le16(high_16_bits(inode->i_uid)); | |
4976 | raw_inode->i_gid_high = | |
4977 | cpu_to_le16(high_16_bits(inode->i_gid)); | |
4978 | } else { | |
4979 | raw_inode->i_uid_high = 0; | |
4980 | raw_inode->i_gid_high = 0; | |
4981 | } | |
4982 | } else { | |
4983 | raw_inode->i_uid_low = | |
4984 | cpu_to_le16(fs_high2lowuid(inode->i_uid)); | |
4985 | raw_inode->i_gid_low = | |
4986 | cpu_to_le16(fs_high2lowgid(inode->i_gid)); | |
4987 | raw_inode->i_uid_high = 0; | |
4988 | raw_inode->i_gid_high = 0; | |
4989 | } | |
4990 | raw_inode->i_links_count = cpu_to_le16(inode->i_nlink); | |
ef7f3835 KS |
4991 | |
4992 | EXT4_INODE_SET_XTIME(i_ctime, inode, raw_inode); | |
4993 | EXT4_INODE_SET_XTIME(i_mtime, inode, raw_inode); | |
4994 | EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode); | |
4995 | EXT4_EINODE_SET_XTIME(i_crtime, ei, raw_inode); | |
4996 | ||
0fc1b451 AK |
4997 | if (ext4_inode_blocks_set(handle, raw_inode, ei)) |
4998 | goto out_brelse; | |
ac27a0ec | 4999 | raw_inode->i_dtime = cpu_to_le32(ei->i_dtime); |
1b9c12f4 | 5000 | raw_inode->i_flags = cpu_to_le32(ei->i_flags); |
9b8f1f01 MC |
5001 | if (EXT4_SB(inode->i_sb)->s_es->s_creator_os != |
5002 | cpu_to_le32(EXT4_OS_HURD)) | |
a1ddeb7e BP |
5003 | raw_inode->i_file_acl_high = |
5004 | cpu_to_le16(ei->i_file_acl >> 32); | |
7973c0c1 | 5005 | raw_inode->i_file_acl_lo = cpu_to_le32(ei->i_file_acl); |
a48380f7 AK |
5006 | ext4_isize_set(raw_inode, ei->i_disksize); |
5007 | if (ei->i_disksize > 0x7fffffffULL) { | |
5008 | struct super_block *sb = inode->i_sb; | |
5009 | if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, | |
5010 | EXT4_FEATURE_RO_COMPAT_LARGE_FILE) || | |
5011 | EXT4_SB(sb)->s_es->s_rev_level == | |
5012 | cpu_to_le32(EXT4_GOOD_OLD_REV)) { | |
5013 | /* If this is the first large file | |
5014 | * created, add a flag to the superblock. | |
5015 | */ | |
5016 | err = ext4_journal_get_write_access(handle, | |
5017 | EXT4_SB(sb)->s_sbh); | |
5018 | if (err) | |
5019 | goto out_brelse; | |
5020 | ext4_update_dynamic_rev(sb); | |
5021 | EXT4_SET_RO_COMPAT_FEATURE(sb, | |
617ba13b | 5022 | EXT4_FEATURE_RO_COMPAT_LARGE_FILE); |
a48380f7 | 5023 | sb->s_dirt = 1; |
0390131b FM |
5024 | ext4_handle_sync(handle); |
5025 | err = ext4_handle_dirty_metadata(handle, inode, | |
a48380f7 | 5026 | EXT4_SB(sb)->s_sbh); |
ac27a0ec DK |
5027 | } |
5028 | } | |
5029 | raw_inode->i_generation = cpu_to_le32(inode->i_generation); | |
5030 | if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { | |
5031 | if (old_valid_dev(inode->i_rdev)) { | |
5032 | raw_inode->i_block[0] = | |
5033 | cpu_to_le32(old_encode_dev(inode->i_rdev)); | |
5034 | raw_inode->i_block[1] = 0; | |
5035 | } else { | |
5036 | raw_inode->i_block[0] = 0; | |
5037 | raw_inode->i_block[1] = | |
5038 | cpu_to_le32(new_encode_dev(inode->i_rdev)); | |
5039 | raw_inode->i_block[2] = 0; | |
5040 | } | |
de9a55b8 TT |
5041 | } else |
5042 | for (block = 0; block < EXT4_N_BLOCKS; block++) | |
5043 | raw_inode->i_block[block] = ei->i_data[block]; | |
ac27a0ec | 5044 | |
25ec56b5 JNC |
5045 | raw_inode->i_disk_version = cpu_to_le32(inode->i_version); |
5046 | if (ei->i_extra_isize) { | |
5047 | if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi)) | |
5048 | raw_inode->i_version_hi = | |
5049 | cpu_to_le32(inode->i_version >> 32); | |
ac27a0ec | 5050 | raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize); |
25ec56b5 JNC |
5051 | } |
5052 | ||
830156c7 FM |
5053 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
5054 | rc = ext4_handle_dirty_metadata(handle, inode, bh); | |
5055 | if (!err) | |
5056 | err = rc; | |
617ba13b | 5057 | ei->i_state &= ~EXT4_STATE_NEW; |
ac27a0ec DK |
5058 | |
5059 | out_brelse: | |
af5bc92d | 5060 | brelse(bh); |
617ba13b | 5061 | ext4_std_error(inode->i_sb, err); |
ac27a0ec DK |
5062 | return err; |
5063 | } | |
5064 | ||
5065 | /* | |
617ba13b | 5066 | * ext4_write_inode() |
ac27a0ec DK |
5067 | * |
5068 | * We are called from a few places: | |
5069 | * | |
5070 | * - Within generic_file_write() for O_SYNC files. | |
5071 | * Here, there will be no transaction running. We wait for any running | |
5072 | * trasnaction to commit. | |
5073 | * | |
5074 | * - Within sys_sync(), kupdate and such. | |
5075 | * We wait on commit, if tol to. | |
5076 | * | |
5077 | * - Within prune_icache() (PF_MEMALLOC == true) | |
5078 | * Here we simply return. We can't afford to block kswapd on the | |
5079 | * journal commit. | |
5080 | * | |
5081 | * In all cases it is actually safe for us to return without doing anything, | |
5082 | * because the inode has been copied into a raw inode buffer in | |
617ba13b | 5083 | * ext4_mark_inode_dirty(). This is a correctness thing for O_SYNC and for |
ac27a0ec DK |
5084 | * knfsd. |
5085 | * | |
5086 | * Note that we are absolutely dependent upon all inode dirtiers doing the | |
5087 | * right thing: they *must* call mark_inode_dirty() after dirtying info in | |
5088 | * which we are interested. | |
5089 | * | |
5090 | * It would be a bug for them to not do this. The code: | |
5091 | * | |
5092 | * mark_inode_dirty(inode) | |
5093 | * stuff(); | |
5094 | * inode->i_size = expr; | |
5095 | * | |
5096 | * is in error because a kswapd-driven write_inode() could occur while | |
5097 | * `stuff()' is running, and the new i_size will be lost. Plus the inode | |
5098 | * will no longer be on the superblock's dirty inode list. | |
5099 | */ | |
617ba13b | 5100 | int ext4_write_inode(struct inode *inode, int wait) |
ac27a0ec | 5101 | { |
91ac6f43 FM |
5102 | int err; |
5103 | ||
ac27a0ec DK |
5104 | if (current->flags & PF_MEMALLOC) |
5105 | return 0; | |
5106 | ||
91ac6f43 FM |
5107 | if (EXT4_SB(inode->i_sb)->s_journal) { |
5108 | if (ext4_journal_current_handle()) { | |
5109 | jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n"); | |
5110 | dump_stack(); | |
5111 | return -EIO; | |
5112 | } | |
ac27a0ec | 5113 | |
91ac6f43 FM |
5114 | if (!wait) |
5115 | return 0; | |
5116 | ||
5117 | err = ext4_force_commit(inode->i_sb); | |
5118 | } else { | |
5119 | struct ext4_iloc iloc; | |
ac27a0ec | 5120 | |
91ac6f43 FM |
5121 | err = ext4_get_inode_loc(inode, &iloc); |
5122 | if (err) | |
5123 | return err; | |
830156c7 FM |
5124 | if (wait) |
5125 | sync_dirty_buffer(iloc.bh); | |
5126 | if (buffer_req(iloc.bh) && !buffer_uptodate(iloc.bh)) { | |
5127 | ext4_error(inode->i_sb, __func__, | |
5128 | "IO error syncing inode, " | |
5129 | "inode=%lu, block=%llu", | |
5130 | inode->i_ino, | |
5131 | (unsigned long long)iloc.bh->b_blocknr); | |
5132 | err = -EIO; | |
5133 | } | |
91ac6f43 FM |
5134 | } |
5135 | return err; | |
ac27a0ec DK |
5136 | } |
5137 | ||
5138 | /* | |
617ba13b | 5139 | * ext4_setattr() |
ac27a0ec DK |
5140 | * |
5141 | * Called from notify_change. | |
5142 | * | |
5143 | * We want to trap VFS attempts to truncate the file as soon as | |
5144 | * possible. In particular, we want to make sure that when the VFS | |
5145 | * shrinks i_size, we put the inode on the orphan list and modify | |
5146 | * i_disksize immediately, so that during the subsequent flushing of | |
5147 | * dirty pages and freeing of disk blocks, we can guarantee that any | |
5148 | * commit will leave the blocks being flushed in an unused state on | |
5149 | * disk. (On recovery, the inode will get truncated and the blocks will | |
5150 | * be freed, so we have a strong guarantee that no future commit will | |
5151 | * leave these blocks visible to the user.) | |
5152 | * | |
678aaf48 JK |
5153 | * Another thing we have to assure is that if we are in ordered mode |
5154 | * and inode is still attached to the committing transaction, we must | |
5155 | * we start writeout of all the dirty pages which are being truncated. | |
5156 | * This way we are sure that all the data written in the previous | |
5157 | * transaction are already on disk (truncate waits for pages under | |
5158 | * writeback). | |
5159 | * | |
5160 | * Called with inode->i_mutex down. | |
ac27a0ec | 5161 | */ |
617ba13b | 5162 | int ext4_setattr(struct dentry *dentry, struct iattr *attr) |
ac27a0ec DK |
5163 | { |
5164 | struct inode *inode = dentry->d_inode; | |
5165 | int error, rc = 0; | |
5166 | const unsigned int ia_valid = attr->ia_valid; | |
5167 | ||
5168 | error = inode_change_ok(inode, attr); | |
5169 | if (error) | |
5170 | return error; | |
5171 | ||
5172 | if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) || | |
5173 | (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) { | |
5174 | handle_t *handle; | |
5175 | ||
5176 | /* (user+group)*(old+new) structure, inode write (sb, | |
5177 | * inode block, ? - but truncate inode update has it) */ | |
5aca07eb | 5178 | handle = ext4_journal_start(inode, (EXT4_MAXQUOTAS_INIT_BLOCKS(inode->i_sb)+ |
617ba13b | 5179 | EXT4_QUOTA_DEL_BLOCKS(inode->i_sb))+3); |
ac27a0ec DK |
5180 | if (IS_ERR(handle)) { |
5181 | error = PTR_ERR(handle); | |
5182 | goto err_out; | |
5183 | } | |
a269eb18 | 5184 | error = vfs_dq_transfer(inode, attr) ? -EDQUOT : 0; |
ac27a0ec | 5185 | if (error) { |
617ba13b | 5186 | ext4_journal_stop(handle); |
ac27a0ec DK |
5187 | return error; |
5188 | } | |
5189 | /* Update corresponding info in inode so that everything is in | |
5190 | * one transaction */ | |
5191 | if (attr->ia_valid & ATTR_UID) | |
5192 | inode->i_uid = attr->ia_uid; | |
5193 | if (attr->ia_valid & ATTR_GID) | |
5194 | inode->i_gid = attr->ia_gid; | |
617ba13b MC |
5195 | error = ext4_mark_inode_dirty(handle, inode); |
5196 | ext4_journal_stop(handle); | |
ac27a0ec DK |
5197 | } |
5198 | ||
e2b46574 ES |
5199 | if (attr->ia_valid & ATTR_SIZE) { |
5200 | if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) { | |
5201 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
5202 | ||
5203 | if (attr->ia_size > sbi->s_bitmap_maxbytes) { | |
5204 | error = -EFBIG; | |
5205 | goto err_out; | |
5206 | } | |
5207 | } | |
5208 | } | |
5209 | ||
ac27a0ec DK |
5210 | if (S_ISREG(inode->i_mode) && |
5211 | attr->ia_valid & ATTR_SIZE && attr->ia_size < inode->i_size) { | |
5212 | handle_t *handle; | |
5213 | ||
617ba13b | 5214 | handle = ext4_journal_start(inode, 3); |
ac27a0ec DK |
5215 | if (IS_ERR(handle)) { |
5216 | error = PTR_ERR(handle); | |
5217 | goto err_out; | |
5218 | } | |
5219 | ||
617ba13b MC |
5220 | error = ext4_orphan_add(handle, inode); |
5221 | EXT4_I(inode)->i_disksize = attr->ia_size; | |
5222 | rc = ext4_mark_inode_dirty(handle, inode); | |
ac27a0ec DK |
5223 | if (!error) |
5224 | error = rc; | |
617ba13b | 5225 | ext4_journal_stop(handle); |
678aaf48 JK |
5226 | |
5227 | if (ext4_should_order_data(inode)) { | |
5228 | error = ext4_begin_ordered_truncate(inode, | |
5229 | attr->ia_size); | |
5230 | if (error) { | |
5231 | /* Do as much error cleanup as possible */ | |
5232 | handle = ext4_journal_start(inode, 3); | |
5233 | if (IS_ERR(handle)) { | |
5234 | ext4_orphan_del(NULL, inode); | |
5235 | goto err_out; | |
5236 | } | |
5237 | ext4_orphan_del(handle, inode); | |
5238 | ext4_journal_stop(handle); | |
5239 | goto err_out; | |
5240 | } | |
5241 | } | |
ac27a0ec DK |
5242 | } |
5243 | ||
5244 | rc = inode_setattr(inode, attr); | |
5245 | ||
617ba13b | 5246 | /* If inode_setattr's call to ext4_truncate failed to get a |
ac27a0ec DK |
5247 | * transaction handle at all, we need to clean up the in-core |
5248 | * orphan list manually. */ | |
5249 | if (inode->i_nlink) | |
617ba13b | 5250 | ext4_orphan_del(NULL, inode); |
ac27a0ec DK |
5251 | |
5252 | if (!rc && (ia_valid & ATTR_MODE)) | |
617ba13b | 5253 | rc = ext4_acl_chmod(inode); |
ac27a0ec DK |
5254 | |
5255 | err_out: | |
617ba13b | 5256 | ext4_std_error(inode->i_sb, error); |
ac27a0ec DK |
5257 | if (!error) |
5258 | error = rc; | |
5259 | return error; | |
5260 | } | |
5261 | ||
3e3398a0 MC |
5262 | int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry, |
5263 | struct kstat *stat) | |
5264 | { | |
5265 | struct inode *inode; | |
5266 | unsigned long delalloc_blocks; | |
5267 | ||
5268 | inode = dentry->d_inode; | |
5269 | generic_fillattr(inode, stat); | |
5270 | ||
5271 | /* | |
5272 | * We can't update i_blocks if the block allocation is delayed | |
5273 | * otherwise in the case of system crash before the real block | |
5274 | * allocation is done, we will have i_blocks inconsistent with | |
5275 | * on-disk file blocks. | |
5276 | * We always keep i_blocks updated together with real | |
5277 | * allocation. But to not confuse with user, stat | |
5278 | * will return the blocks that include the delayed allocation | |
5279 | * blocks for this file. | |
5280 | */ | |
5281 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); | |
5282 | delalloc_blocks = EXT4_I(inode)->i_reserved_data_blocks; | |
5283 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
5284 | ||
5285 | stat->blocks += (delalloc_blocks << inode->i_sb->s_blocksize_bits)>>9; | |
5286 | return 0; | |
5287 | } | |
ac27a0ec | 5288 | |
a02908f1 MC |
5289 | static int ext4_indirect_trans_blocks(struct inode *inode, int nrblocks, |
5290 | int chunk) | |
5291 | { | |
5292 | int indirects; | |
5293 | ||
5294 | /* if nrblocks are contiguous */ | |
5295 | if (chunk) { | |
5296 | /* | |
5297 | * With N contiguous data blocks, it need at most | |
5298 | * N/EXT4_ADDR_PER_BLOCK(inode->i_sb) indirect blocks | |
5299 | * 2 dindirect blocks | |
5300 | * 1 tindirect block | |
5301 | */ | |
5302 | indirects = nrblocks / EXT4_ADDR_PER_BLOCK(inode->i_sb); | |
5303 | return indirects + 3; | |
5304 | } | |
5305 | /* | |
5306 | * if nrblocks are not contiguous, worse case, each block touch | |
5307 | * a indirect block, and each indirect block touch a double indirect | |
5308 | * block, plus a triple indirect block | |
5309 | */ | |
5310 | indirects = nrblocks * 2 + 1; | |
5311 | return indirects; | |
5312 | } | |
5313 | ||
5314 | static int ext4_index_trans_blocks(struct inode *inode, int nrblocks, int chunk) | |
5315 | { | |
5316 | if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) | |
ac51d837 TT |
5317 | return ext4_indirect_trans_blocks(inode, nrblocks, chunk); |
5318 | return ext4_ext_index_trans_blocks(inode, nrblocks, chunk); | |
a02908f1 | 5319 | } |
ac51d837 | 5320 | |
ac27a0ec | 5321 | /* |
a02908f1 MC |
5322 | * Account for index blocks, block groups bitmaps and block group |
5323 | * descriptor blocks if modify datablocks and index blocks | |
5324 | * worse case, the indexs blocks spread over different block groups | |
ac27a0ec | 5325 | * |
a02908f1 MC |
5326 | * If datablocks are discontiguous, they are possible to spread over |
5327 | * different block groups too. If they are contiugous, with flexbg, | |
5328 | * they could still across block group boundary. | |
ac27a0ec | 5329 | * |
a02908f1 MC |
5330 | * Also account for superblock, inode, quota and xattr blocks |
5331 | */ | |
5332 | int ext4_meta_trans_blocks(struct inode *inode, int nrblocks, int chunk) | |
5333 | { | |
8df9675f TT |
5334 | ext4_group_t groups, ngroups = ext4_get_groups_count(inode->i_sb); |
5335 | int gdpblocks; | |
a02908f1 MC |
5336 | int idxblocks; |
5337 | int ret = 0; | |
5338 | ||
5339 | /* | |
5340 | * How many index blocks need to touch to modify nrblocks? | |
5341 | * The "Chunk" flag indicating whether the nrblocks is | |
5342 | * physically contiguous on disk | |
5343 | * | |
5344 | * For Direct IO and fallocate, they calls get_block to allocate | |
5345 | * one single extent at a time, so they could set the "Chunk" flag | |
5346 | */ | |
5347 | idxblocks = ext4_index_trans_blocks(inode, nrblocks, chunk); | |
5348 | ||
5349 | ret = idxblocks; | |
5350 | ||
5351 | /* | |
5352 | * Now let's see how many group bitmaps and group descriptors need | |
5353 | * to account | |
5354 | */ | |
5355 | groups = idxblocks; | |
5356 | if (chunk) | |
5357 | groups += 1; | |
5358 | else | |
5359 | groups += nrblocks; | |
5360 | ||
5361 | gdpblocks = groups; | |
8df9675f TT |
5362 | if (groups > ngroups) |
5363 | groups = ngroups; | |
a02908f1 MC |
5364 | if (groups > EXT4_SB(inode->i_sb)->s_gdb_count) |
5365 | gdpblocks = EXT4_SB(inode->i_sb)->s_gdb_count; | |
5366 | ||
5367 | /* bitmaps and block group descriptor blocks */ | |
5368 | ret += groups + gdpblocks; | |
5369 | ||
5370 | /* Blocks for super block, inode, quota and xattr blocks */ | |
5371 | ret += EXT4_META_TRANS_BLOCKS(inode->i_sb); | |
5372 | ||
5373 | return ret; | |
5374 | } | |
5375 | ||
5376 | /* | |
5377 | * Calulate the total number of credits to reserve to fit | |
f3bd1f3f MC |
5378 | * the modification of a single pages into a single transaction, |
5379 | * which may include multiple chunks of block allocations. | |
ac27a0ec | 5380 | * |
525f4ed8 | 5381 | * This could be called via ext4_write_begin() |
ac27a0ec | 5382 | * |
525f4ed8 | 5383 | * We need to consider the worse case, when |
a02908f1 | 5384 | * one new block per extent. |
ac27a0ec | 5385 | */ |
a86c6181 | 5386 | int ext4_writepage_trans_blocks(struct inode *inode) |
ac27a0ec | 5387 | { |
617ba13b | 5388 | int bpp = ext4_journal_blocks_per_page(inode); |
ac27a0ec DK |
5389 | int ret; |
5390 | ||
a02908f1 | 5391 | ret = ext4_meta_trans_blocks(inode, bpp, 0); |
a86c6181 | 5392 | |
a02908f1 | 5393 | /* Account for data blocks for journalled mode */ |
617ba13b | 5394 | if (ext4_should_journal_data(inode)) |
a02908f1 | 5395 | ret += bpp; |
ac27a0ec DK |
5396 | return ret; |
5397 | } | |
f3bd1f3f MC |
5398 | |
5399 | /* | |
5400 | * Calculate the journal credits for a chunk of data modification. | |
5401 | * | |
5402 | * This is called from DIO, fallocate or whoever calling | |
12b7ac17 | 5403 | * ext4_get_blocks() to map/allocate a chunk of contigous disk blocks. |
f3bd1f3f MC |
5404 | * |
5405 | * journal buffers for data blocks are not included here, as DIO | |
5406 | * and fallocate do no need to journal data buffers. | |
5407 | */ | |
5408 | int ext4_chunk_trans_blocks(struct inode *inode, int nrblocks) | |
5409 | { | |
5410 | return ext4_meta_trans_blocks(inode, nrblocks, 1); | |
5411 | } | |
5412 | ||
ac27a0ec | 5413 | /* |
617ba13b | 5414 | * The caller must have previously called ext4_reserve_inode_write(). |
ac27a0ec DK |
5415 | * Give this, we know that the caller already has write access to iloc->bh. |
5416 | */ | |
617ba13b | 5417 | int ext4_mark_iloc_dirty(handle_t *handle, |
de9a55b8 | 5418 | struct inode *inode, struct ext4_iloc *iloc) |
ac27a0ec DK |
5419 | { |
5420 | int err = 0; | |
5421 | ||
25ec56b5 JNC |
5422 | if (test_opt(inode->i_sb, I_VERSION)) |
5423 | inode_inc_iversion(inode); | |
5424 | ||
ac27a0ec DK |
5425 | /* the do_update_inode consumes one bh->b_count */ |
5426 | get_bh(iloc->bh); | |
5427 | ||
dab291af | 5428 | /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */ |
830156c7 | 5429 | err = ext4_do_update_inode(handle, inode, iloc); |
ac27a0ec DK |
5430 | put_bh(iloc->bh); |
5431 | return err; | |
5432 | } | |
5433 | ||
5434 | /* | |
5435 | * On success, We end up with an outstanding reference count against | |
5436 | * iloc->bh. This _must_ be cleaned up later. | |
5437 | */ | |
5438 | ||
5439 | int | |
617ba13b MC |
5440 | ext4_reserve_inode_write(handle_t *handle, struct inode *inode, |
5441 | struct ext4_iloc *iloc) | |
ac27a0ec | 5442 | { |
0390131b FM |
5443 | int err; |
5444 | ||
5445 | err = ext4_get_inode_loc(inode, iloc); | |
5446 | if (!err) { | |
5447 | BUFFER_TRACE(iloc->bh, "get_write_access"); | |
5448 | err = ext4_journal_get_write_access(handle, iloc->bh); | |
5449 | if (err) { | |
5450 | brelse(iloc->bh); | |
5451 | iloc->bh = NULL; | |
ac27a0ec DK |
5452 | } |
5453 | } | |
617ba13b | 5454 | ext4_std_error(inode->i_sb, err); |
ac27a0ec DK |
5455 | return err; |
5456 | } | |
5457 | ||
6dd4ee7c KS |
5458 | /* |
5459 | * Expand an inode by new_extra_isize bytes. | |
5460 | * Returns 0 on success or negative error number on failure. | |
5461 | */ | |
1d03ec98 AK |
5462 | static int ext4_expand_extra_isize(struct inode *inode, |
5463 | unsigned int new_extra_isize, | |
5464 | struct ext4_iloc iloc, | |
5465 | handle_t *handle) | |
6dd4ee7c KS |
5466 | { |
5467 | struct ext4_inode *raw_inode; | |
5468 | struct ext4_xattr_ibody_header *header; | |
5469 | struct ext4_xattr_entry *entry; | |
5470 | ||
5471 | if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) | |
5472 | return 0; | |
5473 | ||
5474 | raw_inode = ext4_raw_inode(&iloc); | |
5475 | ||
5476 | header = IHDR(inode, raw_inode); | |
5477 | entry = IFIRST(header); | |
5478 | ||
5479 | /* No extended attributes present */ | |
5480 | if (!(EXT4_I(inode)->i_state & EXT4_STATE_XATTR) || | |
5481 | header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)) { | |
5482 | memset((void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE, 0, | |
5483 | new_extra_isize); | |
5484 | EXT4_I(inode)->i_extra_isize = new_extra_isize; | |
5485 | return 0; | |
5486 | } | |
5487 | ||
5488 | /* try to expand with EAs present */ | |
5489 | return ext4_expand_extra_isize_ea(inode, new_extra_isize, | |
5490 | raw_inode, handle); | |
5491 | } | |
5492 | ||
ac27a0ec DK |
5493 | /* |
5494 | * What we do here is to mark the in-core inode as clean with respect to inode | |
5495 | * dirtiness (it may still be data-dirty). | |
5496 | * This means that the in-core inode may be reaped by prune_icache | |
5497 | * without having to perform any I/O. This is a very good thing, | |
5498 | * because *any* task may call prune_icache - even ones which | |
5499 | * have a transaction open against a different journal. | |
5500 | * | |
5501 | * Is this cheating? Not really. Sure, we haven't written the | |
5502 | * inode out, but prune_icache isn't a user-visible syncing function. | |
5503 | * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync) | |
5504 | * we start and wait on commits. | |
5505 | * | |
5506 | * Is this efficient/effective? Well, we're being nice to the system | |
5507 | * by cleaning up our inodes proactively so they can be reaped | |
5508 | * without I/O. But we are potentially leaving up to five seconds' | |
5509 | * worth of inodes floating about which prune_icache wants us to | |
5510 | * write out. One way to fix that would be to get prune_icache() | |
5511 | * to do a write_super() to free up some memory. It has the desired | |
5512 | * effect. | |
5513 | */ | |
617ba13b | 5514 | int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode) |
ac27a0ec | 5515 | { |
617ba13b | 5516 | struct ext4_iloc iloc; |
6dd4ee7c KS |
5517 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
5518 | static unsigned int mnt_count; | |
5519 | int err, ret; | |
ac27a0ec DK |
5520 | |
5521 | might_sleep(); | |
617ba13b | 5522 | err = ext4_reserve_inode_write(handle, inode, &iloc); |
0390131b FM |
5523 | if (ext4_handle_valid(handle) && |
5524 | EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize && | |
6dd4ee7c KS |
5525 | !(EXT4_I(inode)->i_state & EXT4_STATE_NO_EXPAND)) { |
5526 | /* | |
5527 | * We need extra buffer credits since we may write into EA block | |
5528 | * with this same handle. If journal_extend fails, then it will | |
5529 | * only result in a minor loss of functionality for that inode. | |
5530 | * If this is felt to be critical, then e2fsck should be run to | |
5531 | * force a large enough s_min_extra_isize. | |
5532 | */ | |
5533 | if ((jbd2_journal_extend(handle, | |
5534 | EXT4_DATA_TRANS_BLOCKS(inode->i_sb))) == 0) { | |
5535 | ret = ext4_expand_extra_isize(inode, | |
5536 | sbi->s_want_extra_isize, | |
5537 | iloc, handle); | |
5538 | if (ret) { | |
5539 | EXT4_I(inode)->i_state |= EXT4_STATE_NO_EXPAND; | |
c1bddad9 AK |
5540 | if (mnt_count != |
5541 | le16_to_cpu(sbi->s_es->s_mnt_count)) { | |
46e665e9 | 5542 | ext4_warning(inode->i_sb, __func__, |
6dd4ee7c KS |
5543 | "Unable to expand inode %lu. Delete" |
5544 | " some EAs or run e2fsck.", | |
5545 | inode->i_ino); | |
c1bddad9 AK |
5546 | mnt_count = |
5547 | le16_to_cpu(sbi->s_es->s_mnt_count); | |
6dd4ee7c KS |
5548 | } |
5549 | } | |
5550 | } | |
5551 | } | |
ac27a0ec | 5552 | if (!err) |
617ba13b | 5553 | err = ext4_mark_iloc_dirty(handle, inode, &iloc); |
ac27a0ec DK |
5554 | return err; |
5555 | } | |
5556 | ||
5557 | /* | |
617ba13b | 5558 | * ext4_dirty_inode() is called from __mark_inode_dirty() |
ac27a0ec DK |
5559 | * |
5560 | * We're really interested in the case where a file is being extended. | |
5561 | * i_size has been changed by generic_commit_write() and we thus need | |
5562 | * to include the updated inode in the current transaction. | |
5563 | * | |
a269eb18 | 5564 | * Also, vfs_dq_alloc_block() will always dirty the inode when blocks |
ac27a0ec DK |
5565 | * are allocated to the file. |
5566 | * | |
5567 | * If the inode is marked synchronous, we don't honour that here - doing | |
5568 | * so would cause a commit on atime updates, which we don't bother doing. | |
5569 | * We handle synchronous inodes at the highest possible level. | |
5570 | */ | |
617ba13b | 5571 | void ext4_dirty_inode(struct inode *inode) |
ac27a0ec | 5572 | { |
ac27a0ec DK |
5573 | handle_t *handle; |
5574 | ||
617ba13b | 5575 | handle = ext4_journal_start(inode, 2); |
ac27a0ec DK |
5576 | if (IS_ERR(handle)) |
5577 | goto out; | |
f3dc272f | 5578 | |
f3dc272f CW |
5579 | ext4_mark_inode_dirty(handle, inode); |
5580 | ||
617ba13b | 5581 | ext4_journal_stop(handle); |
ac27a0ec DK |
5582 | out: |
5583 | return; | |
5584 | } | |
5585 | ||
5586 | #if 0 | |
5587 | /* | |
5588 | * Bind an inode's backing buffer_head into this transaction, to prevent | |
5589 | * it from being flushed to disk early. Unlike | |
617ba13b | 5590 | * ext4_reserve_inode_write, this leaves behind no bh reference and |
ac27a0ec DK |
5591 | * returns no iloc structure, so the caller needs to repeat the iloc |
5592 | * lookup to mark the inode dirty later. | |
5593 | */ | |
617ba13b | 5594 | static int ext4_pin_inode(handle_t *handle, struct inode *inode) |
ac27a0ec | 5595 | { |
617ba13b | 5596 | struct ext4_iloc iloc; |
ac27a0ec DK |
5597 | |
5598 | int err = 0; | |
5599 | if (handle) { | |
617ba13b | 5600 | err = ext4_get_inode_loc(inode, &iloc); |
ac27a0ec DK |
5601 | if (!err) { |
5602 | BUFFER_TRACE(iloc.bh, "get_write_access"); | |
dab291af | 5603 | err = jbd2_journal_get_write_access(handle, iloc.bh); |
ac27a0ec | 5604 | if (!err) |
0390131b FM |
5605 | err = ext4_handle_dirty_metadata(handle, |
5606 | inode, | |
5607 | iloc.bh); | |
ac27a0ec DK |
5608 | brelse(iloc.bh); |
5609 | } | |
5610 | } | |
617ba13b | 5611 | ext4_std_error(inode->i_sb, err); |
ac27a0ec DK |
5612 | return err; |
5613 | } | |
5614 | #endif | |
5615 | ||
617ba13b | 5616 | int ext4_change_inode_journal_flag(struct inode *inode, int val) |
ac27a0ec DK |
5617 | { |
5618 | journal_t *journal; | |
5619 | handle_t *handle; | |
5620 | int err; | |
5621 | ||
5622 | /* | |
5623 | * We have to be very careful here: changing a data block's | |
5624 | * journaling status dynamically is dangerous. If we write a | |
5625 | * data block to the journal, change the status and then delete | |
5626 | * that block, we risk forgetting to revoke the old log record | |
5627 | * from the journal and so a subsequent replay can corrupt data. | |
5628 | * So, first we make sure that the journal is empty and that | |
5629 | * nobody is changing anything. | |
5630 | */ | |
5631 | ||
617ba13b | 5632 | journal = EXT4_JOURNAL(inode); |
0390131b FM |
5633 | if (!journal) |
5634 | return 0; | |
d699594d | 5635 | if (is_journal_aborted(journal)) |
ac27a0ec DK |
5636 | return -EROFS; |
5637 | ||
dab291af MC |
5638 | jbd2_journal_lock_updates(journal); |
5639 | jbd2_journal_flush(journal); | |
ac27a0ec DK |
5640 | |
5641 | /* | |
5642 | * OK, there are no updates running now, and all cached data is | |
5643 | * synced to disk. We are now in a completely consistent state | |
5644 | * which doesn't have anything in the journal, and we know that | |
5645 | * no filesystem updates are running, so it is safe to modify | |
5646 | * the inode's in-core data-journaling state flag now. | |
5647 | */ | |
5648 | ||
5649 | if (val) | |
617ba13b | 5650 | EXT4_I(inode)->i_flags |= EXT4_JOURNAL_DATA_FL; |
ac27a0ec | 5651 | else |
617ba13b MC |
5652 | EXT4_I(inode)->i_flags &= ~EXT4_JOURNAL_DATA_FL; |
5653 | ext4_set_aops(inode); | |
ac27a0ec | 5654 | |
dab291af | 5655 | jbd2_journal_unlock_updates(journal); |
ac27a0ec DK |
5656 | |
5657 | /* Finally we can mark the inode as dirty. */ | |
5658 | ||
617ba13b | 5659 | handle = ext4_journal_start(inode, 1); |
ac27a0ec DK |
5660 | if (IS_ERR(handle)) |
5661 | return PTR_ERR(handle); | |
5662 | ||
617ba13b | 5663 | err = ext4_mark_inode_dirty(handle, inode); |
0390131b | 5664 | ext4_handle_sync(handle); |
617ba13b MC |
5665 | ext4_journal_stop(handle); |
5666 | ext4_std_error(inode->i_sb, err); | |
ac27a0ec DK |
5667 | |
5668 | return err; | |
5669 | } | |
2e9ee850 AK |
5670 | |
5671 | static int ext4_bh_unmapped(handle_t *handle, struct buffer_head *bh) | |
5672 | { | |
5673 | return !buffer_mapped(bh); | |
5674 | } | |
5675 | ||
c2ec175c | 5676 | int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
2e9ee850 | 5677 | { |
c2ec175c | 5678 | struct page *page = vmf->page; |
2e9ee850 AK |
5679 | loff_t size; |
5680 | unsigned long len; | |
5681 | int ret = -EINVAL; | |
79f0be8d | 5682 | void *fsdata; |
2e9ee850 AK |
5683 | struct file *file = vma->vm_file; |
5684 | struct inode *inode = file->f_path.dentry->d_inode; | |
5685 | struct address_space *mapping = inode->i_mapping; | |
5686 | ||
5687 | /* | |
5688 | * Get i_alloc_sem to stop truncates messing with the inode. We cannot | |
5689 | * get i_mutex because we are already holding mmap_sem. | |
5690 | */ | |
5691 | down_read(&inode->i_alloc_sem); | |
5692 | size = i_size_read(inode); | |
5693 | if (page->mapping != mapping || size <= page_offset(page) | |
5694 | || !PageUptodate(page)) { | |
5695 | /* page got truncated from under us? */ | |
5696 | goto out_unlock; | |
5697 | } | |
5698 | ret = 0; | |
5699 | if (PageMappedToDisk(page)) | |
5700 | goto out_unlock; | |
5701 | ||
5702 | if (page->index == size >> PAGE_CACHE_SHIFT) | |
5703 | len = size & ~PAGE_CACHE_MASK; | |
5704 | else | |
5705 | len = PAGE_CACHE_SIZE; | |
5706 | ||
a827eaff AK |
5707 | lock_page(page); |
5708 | /* | |
5709 | * return if we have all the buffers mapped. This avoid | |
5710 | * the need to call write_begin/write_end which does a | |
5711 | * journal_start/journal_stop which can block and take | |
5712 | * long time | |
5713 | */ | |
2e9ee850 | 5714 | if (page_has_buffers(page)) { |
2e9ee850 | 5715 | if (!walk_page_buffers(NULL, page_buffers(page), 0, len, NULL, |
a827eaff AK |
5716 | ext4_bh_unmapped)) { |
5717 | unlock_page(page); | |
2e9ee850 | 5718 | goto out_unlock; |
a827eaff | 5719 | } |
2e9ee850 | 5720 | } |
a827eaff | 5721 | unlock_page(page); |
2e9ee850 AK |
5722 | /* |
5723 | * OK, we need to fill the hole... Do write_begin write_end | |
5724 | * to do block allocation/reservation.We are not holding | |
5725 | * inode.i__mutex here. That allow * parallel write_begin, | |
5726 | * write_end call. lock_page prevent this from happening | |
5727 | * on the same page though | |
5728 | */ | |
5729 | ret = mapping->a_ops->write_begin(file, mapping, page_offset(page), | |
79f0be8d | 5730 | len, AOP_FLAG_UNINTERRUPTIBLE, &page, &fsdata); |
2e9ee850 AK |
5731 | if (ret < 0) |
5732 | goto out_unlock; | |
5733 | ret = mapping->a_ops->write_end(file, mapping, page_offset(page), | |
79f0be8d | 5734 | len, len, page, fsdata); |
2e9ee850 AK |
5735 | if (ret < 0) |
5736 | goto out_unlock; | |
5737 | ret = 0; | |
5738 | out_unlock: | |
c2ec175c NP |
5739 | if (ret) |
5740 | ret = VM_FAULT_SIGBUS; | |
2e9ee850 AK |
5741 | up_read(&inode->i_alloc_sem); |
5742 | return ret; | |
5743 | } |