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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> | |
3dcf5451 | 40 | #include "ext4_jbd2.h" |
ac27a0ec DK |
41 | #include "xattr.h" |
42 | #include "acl.h" | |
d2a17637 | 43 | #include "ext4_extents.h" |
ac27a0ec | 44 | |
a1d6cc56 AK |
45 | #define MPAGE_DA_EXTENT_TAIL 0x01 |
46 | ||
678aaf48 JK |
47 | static inline int ext4_begin_ordered_truncate(struct inode *inode, |
48 | loff_t new_size) | |
49 | { | |
7f5aa215 JK |
50 | return jbd2_journal_begin_ordered_truncate( |
51 | EXT4_SB(inode->i_sb)->s_journal, | |
52 | &EXT4_I(inode)->jinode, | |
53 | new_size); | |
678aaf48 JK |
54 | } |
55 | ||
64769240 AT |
56 | static void ext4_invalidatepage(struct page *page, unsigned long offset); |
57 | ||
ac27a0ec DK |
58 | /* |
59 | * Test whether an inode is a fast symlink. | |
60 | */ | |
617ba13b | 61 | static int ext4_inode_is_fast_symlink(struct inode *inode) |
ac27a0ec | 62 | { |
617ba13b | 63 | int ea_blocks = EXT4_I(inode)->i_file_acl ? |
ac27a0ec DK |
64 | (inode->i_sb->s_blocksize >> 9) : 0; |
65 | ||
66 | return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0); | |
67 | } | |
68 | ||
69 | /* | |
617ba13b | 70 | * The ext4 forget function must perform a revoke if we are freeing data |
ac27a0ec DK |
71 | * which has been journaled. Metadata (eg. indirect blocks) must be |
72 | * revoked in all cases. | |
73 | * | |
74 | * "bh" may be NULL: a metadata block may have been freed from memory | |
75 | * but there may still be a record of it in the journal, and that record | |
76 | * still needs to be revoked. | |
0390131b FM |
77 | * |
78 | * If the handle isn't valid we're not journaling so there's nothing to do. | |
ac27a0ec | 79 | */ |
617ba13b MC |
80 | int ext4_forget(handle_t *handle, int is_metadata, struct inode *inode, |
81 | struct buffer_head *bh, ext4_fsblk_t blocknr) | |
ac27a0ec DK |
82 | { |
83 | int err; | |
84 | ||
0390131b FM |
85 | if (!ext4_handle_valid(handle)) |
86 | return 0; | |
87 | ||
ac27a0ec DK |
88 | might_sleep(); |
89 | ||
90 | BUFFER_TRACE(bh, "enter"); | |
91 | ||
92 | jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, " | |
93 | "data mode %lx\n", | |
94 | bh, is_metadata, inode->i_mode, | |
95 | test_opt(inode->i_sb, DATA_FLAGS)); | |
96 | ||
97 | /* Never use the revoke function if we are doing full data | |
98 | * journaling: there is no need to, and a V1 superblock won't | |
99 | * support it. Otherwise, only skip the revoke on un-journaled | |
100 | * data blocks. */ | |
101 | ||
617ba13b MC |
102 | if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA || |
103 | (!is_metadata && !ext4_should_journal_data(inode))) { | |
ac27a0ec | 104 | if (bh) { |
dab291af | 105 | BUFFER_TRACE(bh, "call jbd2_journal_forget"); |
617ba13b | 106 | return ext4_journal_forget(handle, bh); |
ac27a0ec DK |
107 | } |
108 | return 0; | |
109 | } | |
110 | ||
111 | /* | |
112 | * data!=journal && (is_metadata || should_journal_data(inode)) | |
113 | */ | |
617ba13b MC |
114 | BUFFER_TRACE(bh, "call ext4_journal_revoke"); |
115 | err = ext4_journal_revoke(handle, blocknr, bh); | |
ac27a0ec | 116 | if (err) |
46e665e9 | 117 | ext4_abort(inode->i_sb, __func__, |
ac27a0ec DK |
118 | "error %d when attempting revoke", err); |
119 | BUFFER_TRACE(bh, "exit"); | |
120 | return err; | |
121 | } | |
122 | ||
123 | /* | |
124 | * Work out how many blocks we need to proceed with the next chunk of a | |
125 | * truncate transaction. | |
126 | */ | |
127 | static unsigned long blocks_for_truncate(struct inode *inode) | |
128 | { | |
725d26d3 | 129 | ext4_lblk_t needed; |
ac27a0ec DK |
130 | |
131 | needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9); | |
132 | ||
133 | /* Give ourselves just enough room to cope with inodes in which | |
134 | * i_blocks is corrupt: we've seen disk corruptions in the past | |
135 | * which resulted in random data in an inode which looked enough | |
617ba13b | 136 | * like a regular file for ext4 to try to delete it. Things |
ac27a0ec DK |
137 | * will go a bit crazy if that happens, but at least we should |
138 | * try not to panic the whole kernel. */ | |
139 | if (needed < 2) | |
140 | needed = 2; | |
141 | ||
142 | /* But we need to bound the transaction so we don't overflow the | |
143 | * journal. */ | |
617ba13b MC |
144 | if (needed > EXT4_MAX_TRANS_DATA) |
145 | needed = EXT4_MAX_TRANS_DATA; | |
ac27a0ec | 146 | |
617ba13b | 147 | return EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + needed; |
ac27a0ec DK |
148 | } |
149 | ||
150 | /* | |
151 | * Truncate transactions can be complex and absolutely huge. So we need to | |
152 | * be able to restart the transaction at a conventient checkpoint to make | |
153 | * sure we don't overflow the journal. | |
154 | * | |
155 | * start_transaction gets us a new handle for a truncate transaction, | |
156 | * and extend_transaction tries to extend the existing one a bit. If | |
157 | * extend fails, we need to propagate the failure up and restart the | |
158 | * transaction in the top-level truncate loop. --sct | |
159 | */ | |
160 | static handle_t *start_transaction(struct inode *inode) | |
161 | { | |
162 | handle_t *result; | |
163 | ||
617ba13b | 164 | result = ext4_journal_start(inode, blocks_for_truncate(inode)); |
ac27a0ec DK |
165 | if (!IS_ERR(result)) |
166 | return result; | |
167 | ||
617ba13b | 168 | ext4_std_error(inode->i_sb, PTR_ERR(result)); |
ac27a0ec DK |
169 | return result; |
170 | } | |
171 | ||
172 | /* | |
173 | * Try to extend this transaction for the purposes of truncation. | |
174 | * | |
175 | * Returns 0 if we managed to create more room. If we can't create more | |
176 | * room, and the transaction must be restarted we return 1. | |
177 | */ | |
178 | static int try_to_extend_transaction(handle_t *handle, struct inode *inode) | |
179 | { | |
0390131b FM |
180 | if (!ext4_handle_valid(handle)) |
181 | return 0; | |
182 | if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1)) | |
ac27a0ec | 183 | return 0; |
617ba13b | 184 | if (!ext4_journal_extend(handle, blocks_for_truncate(inode))) |
ac27a0ec DK |
185 | return 0; |
186 | return 1; | |
187 | } | |
188 | ||
189 | /* | |
190 | * Restart the transaction associated with *handle. This does a commit, | |
191 | * so before we call here everything must be consistently dirtied against | |
192 | * this transaction. | |
193 | */ | |
617ba13b | 194 | static int ext4_journal_test_restart(handle_t *handle, struct inode *inode) |
ac27a0ec | 195 | { |
0390131b | 196 | BUG_ON(EXT4_JOURNAL(inode) == NULL); |
ac27a0ec | 197 | jbd_debug(2, "restarting handle %p\n", handle); |
617ba13b | 198 | return ext4_journal_restart(handle, blocks_for_truncate(inode)); |
ac27a0ec DK |
199 | } |
200 | ||
201 | /* | |
202 | * Called at the last iput() if i_nlink is zero. | |
203 | */ | |
af5bc92d | 204 | void ext4_delete_inode(struct inode *inode) |
ac27a0ec DK |
205 | { |
206 | handle_t *handle; | |
bc965ab3 | 207 | int err; |
ac27a0ec | 208 | |
678aaf48 JK |
209 | if (ext4_should_order_data(inode)) |
210 | ext4_begin_ordered_truncate(inode, 0); | |
ac27a0ec DK |
211 | truncate_inode_pages(&inode->i_data, 0); |
212 | ||
213 | if (is_bad_inode(inode)) | |
214 | goto no_delete; | |
215 | ||
bc965ab3 | 216 | handle = ext4_journal_start(inode, blocks_for_truncate(inode)+3); |
ac27a0ec | 217 | if (IS_ERR(handle)) { |
bc965ab3 | 218 | ext4_std_error(inode->i_sb, PTR_ERR(handle)); |
ac27a0ec DK |
219 | /* |
220 | * If we're going to skip the normal cleanup, we still need to | |
221 | * make sure that the in-core orphan linked list is properly | |
222 | * cleaned up. | |
223 | */ | |
617ba13b | 224 | ext4_orphan_del(NULL, inode); |
ac27a0ec DK |
225 | goto no_delete; |
226 | } | |
227 | ||
228 | if (IS_SYNC(inode)) | |
0390131b | 229 | ext4_handle_sync(handle); |
ac27a0ec | 230 | inode->i_size = 0; |
bc965ab3 TT |
231 | err = ext4_mark_inode_dirty(handle, inode); |
232 | if (err) { | |
233 | ext4_warning(inode->i_sb, __func__, | |
234 | "couldn't mark inode dirty (err %d)", err); | |
235 | goto stop_handle; | |
236 | } | |
ac27a0ec | 237 | if (inode->i_blocks) |
617ba13b | 238 | ext4_truncate(inode); |
bc965ab3 TT |
239 | |
240 | /* | |
241 | * ext4_ext_truncate() doesn't reserve any slop when it | |
242 | * restarts journal transactions; therefore there may not be | |
243 | * enough credits left in the handle to remove the inode from | |
244 | * the orphan list and set the dtime field. | |
245 | */ | |
0390131b | 246 | if (!ext4_handle_has_enough_credits(handle, 3)) { |
bc965ab3 TT |
247 | err = ext4_journal_extend(handle, 3); |
248 | if (err > 0) | |
249 | err = ext4_journal_restart(handle, 3); | |
250 | if (err != 0) { | |
251 | ext4_warning(inode->i_sb, __func__, | |
252 | "couldn't extend journal (err %d)", err); | |
253 | stop_handle: | |
254 | ext4_journal_stop(handle); | |
255 | goto no_delete; | |
256 | } | |
257 | } | |
258 | ||
ac27a0ec | 259 | /* |
617ba13b | 260 | * Kill off the orphan record which ext4_truncate created. |
ac27a0ec | 261 | * AKPM: I think this can be inside the above `if'. |
617ba13b | 262 | * Note that ext4_orphan_del() has to be able to cope with the |
ac27a0ec | 263 | * deletion of a non-existent orphan - this is because we don't |
617ba13b | 264 | * know if ext4_truncate() actually created an orphan record. |
ac27a0ec DK |
265 | * (Well, we could do this if we need to, but heck - it works) |
266 | */ | |
617ba13b MC |
267 | ext4_orphan_del(handle, inode); |
268 | EXT4_I(inode)->i_dtime = get_seconds(); | |
ac27a0ec DK |
269 | |
270 | /* | |
271 | * One subtle ordering requirement: if anything has gone wrong | |
272 | * (transaction abort, IO errors, whatever), then we can still | |
273 | * do these next steps (the fs will already have been marked as | |
274 | * having errors), but we can't free the inode if the mark_dirty | |
275 | * fails. | |
276 | */ | |
617ba13b | 277 | if (ext4_mark_inode_dirty(handle, inode)) |
ac27a0ec DK |
278 | /* If that failed, just do the required in-core inode clear. */ |
279 | clear_inode(inode); | |
280 | else | |
617ba13b MC |
281 | ext4_free_inode(handle, inode); |
282 | ext4_journal_stop(handle); | |
ac27a0ec DK |
283 | return; |
284 | no_delete: | |
285 | clear_inode(inode); /* We must guarantee clearing of inode... */ | |
286 | } | |
287 | ||
288 | typedef struct { | |
289 | __le32 *p; | |
290 | __le32 key; | |
291 | struct buffer_head *bh; | |
292 | } Indirect; | |
293 | ||
294 | static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v) | |
295 | { | |
296 | p->key = *(p->p = v); | |
297 | p->bh = bh; | |
298 | } | |
299 | ||
ac27a0ec | 300 | /** |
617ba13b | 301 | * ext4_block_to_path - parse the block number into array of offsets |
ac27a0ec DK |
302 | * @inode: inode in question (we are only interested in its superblock) |
303 | * @i_block: block number to be parsed | |
304 | * @offsets: array to store the offsets in | |
8c55e204 DK |
305 | * @boundary: set this non-zero if the referred-to block is likely to be |
306 | * followed (on disk) by an indirect block. | |
ac27a0ec | 307 | * |
617ba13b | 308 | * To store the locations of file's data ext4 uses a data structure common |
ac27a0ec DK |
309 | * for UNIX filesystems - tree of pointers anchored in the inode, with |
310 | * data blocks at leaves and indirect blocks in intermediate nodes. | |
311 | * This function translates the block number into path in that tree - | |
312 | * return value is the path length and @offsets[n] is the offset of | |
313 | * pointer to (n+1)th node in the nth one. If @block is out of range | |
314 | * (negative or too large) warning is printed and zero returned. | |
315 | * | |
316 | * Note: function doesn't find node addresses, so no IO is needed. All | |
317 | * we need to know is the capacity of indirect blocks (taken from the | |
318 | * inode->i_sb). | |
319 | */ | |
320 | ||
321 | /* | |
322 | * Portability note: the last comparison (check that we fit into triple | |
323 | * indirect block) is spelled differently, because otherwise on an | |
324 | * architecture with 32-bit longs and 8Kb pages we might get into trouble | |
325 | * if our filesystem had 8Kb blocks. We might use long long, but that would | |
326 | * kill us on x86. Oh, well, at least the sign propagation does not matter - | |
327 | * i_block would have to be negative in the very beginning, so we would not | |
328 | * get there at all. | |
329 | */ | |
330 | ||
617ba13b | 331 | static int ext4_block_to_path(struct inode *inode, |
725d26d3 AK |
332 | ext4_lblk_t i_block, |
333 | ext4_lblk_t offsets[4], int *boundary) | |
ac27a0ec | 334 | { |
617ba13b MC |
335 | int ptrs = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
336 | int ptrs_bits = EXT4_ADDR_PER_BLOCK_BITS(inode->i_sb); | |
337 | const long direct_blocks = EXT4_NDIR_BLOCKS, | |
ac27a0ec DK |
338 | indirect_blocks = ptrs, |
339 | double_blocks = (1 << (ptrs_bits * 2)); | |
340 | int n = 0; | |
341 | int final = 0; | |
342 | ||
343 | if (i_block < 0) { | |
af5bc92d | 344 | ext4_warning(inode->i_sb, "ext4_block_to_path", "block < 0"); |
ac27a0ec DK |
345 | } else if (i_block < direct_blocks) { |
346 | offsets[n++] = i_block; | |
347 | final = direct_blocks; | |
af5bc92d | 348 | } else if ((i_block -= direct_blocks) < indirect_blocks) { |
617ba13b | 349 | offsets[n++] = EXT4_IND_BLOCK; |
ac27a0ec DK |
350 | offsets[n++] = i_block; |
351 | final = ptrs; | |
352 | } else if ((i_block -= indirect_blocks) < double_blocks) { | |
617ba13b | 353 | offsets[n++] = EXT4_DIND_BLOCK; |
ac27a0ec DK |
354 | offsets[n++] = i_block >> ptrs_bits; |
355 | offsets[n++] = i_block & (ptrs - 1); | |
356 | final = ptrs; | |
357 | } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) { | |
617ba13b | 358 | offsets[n++] = EXT4_TIND_BLOCK; |
ac27a0ec DK |
359 | offsets[n++] = i_block >> (ptrs_bits * 2); |
360 | offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1); | |
361 | offsets[n++] = i_block & (ptrs - 1); | |
362 | final = ptrs; | |
363 | } else { | |
e2b46574 | 364 | ext4_warning(inode->i_sb, "ext4_block_to_path", |
06a279d6 | 365 | "block %lu > max in inode %lu", |
e2b46574 | 366 | i_block + direct_blocks + |
06a279d6 | 367 | indirect_blocks + double_blocks, inode->i_ino); |
ac27a0ec DK |
368 | } |
369 | if (boundary) | |
370 | *boundary = final - 1 - (i_block & (ptrs - 1)); | |
371 | return n; | |
372 | } | |
373 | ||
fe2c8191 | 374 | static int __ext4_check_blockref(const char *function, struct inode *inode, |
6fd058f7 TT |
375 | __le32 *p, unsigned int max) |
376 | { | |
f73953c0 | 377 | __le32 *bref = p; |
6fd058f7 TT |
378 | unsigned int blk; |
379 | ||
fe2c8191 | 380 | while (bref < p+max) { |
6fd058f7 TT |
381 | blk = le32_to_cpu(*bref++); |
382 | if (blk && | |
383 | unlikely(!ext4_data_block_valid(EXT4_SB(inode->i_sb), | |
384 | blk, 1))) { | |
fe2c8191 | 385 | ext4_error(inode->i_sb, function, |
6fd058f7 TT |
386 | "invalid block reference %u " |
387 | "in inode #%lu", blk, inode->i_ino); | |
fe2c8191 TN |
388 | return -EIO; |
389 | } | |
fe2c8191 TN |
390 | } |
391 | return 0; | |
392 | } | |
393 | ||
394 | ||
395 | #define ext4_check_indirect_blockref(inode, bh) \ | |
396 | __ext4_check_blockref(__func__, inode, (__le32 *)(bh)->b_data, \ | |
397 | EXT4_ADDR_PER_BLOCK((inode)->i_sb)) | |
398 | ||
399 | #define ext4_check_inode_blockref(inode) \ | |
400 | __ext4_check_blockref(__func__, inode, EXT4_I(inode)->i_data, \ | |
401 | EXT4_NDIR_BLOCKS) | |
402 | ||
ac27a0ec | 403 | /** |
617ba13b | 404 | * ext4_get_branch - read the chain of indirect blocks leading to data |
ac27a0ec DK |
405 | * @inode: inode in question |
406 | * @depth: depth of the chain (1 - direct pointer, etc.) | |
407 | * @offsets: offsets of pointers in inode/indirect blocks | |
408 | * @chain: place to store the result | |
409 | * @err: here we store the error value | |
410 | * | |
411 | * Function fills the array of triples <key, p, bh> and returns %NULL | |
412 | * if everything went OK or the pointer to the last filled triple | |
413 | * (incomplete one) otherwise. Upon the return chain[i].key contains | |
414 | * the number of (i+1)-th block in the chain (as it is stored in memory, | |
415 | * i.e. little-endian 32-bit), chain[i].p contains the address of that | |
416 | * number (it points into struct inode for i==0 and into the bh->b_data | |
417 | * for i>0) and chain[i].bh points to the buffer_head of i-th indirect | |
418 | * block for i>0 and NULL for i==0. In other words, it holds the block | |
419 | * numbers of the chain, addresses they were taken from (and where we can | |
420 | * verify that chain did not change) and buffer_heads hosting these | |
421 | * numbers. | |
422 | * | |
423 | * Function stops when it stumbles upon zero pointer (absent block) | |
424 | * (pointer to last triple returned, *@err == 0) | |
425 | * or when it gets an IO error reading an indirect block | |
426 | * (ditto, *@err == -EIO) | |
ac27a0ec DK |
427 | * or when it reads all @depth-1 indirect blocks successfully and finds |
428 | * the whole chain, all way to the data (returns %NULL, *err == 0). | |
c278bfec AK |
429 | * |
430 | * Need to be called with | |
0e855ac8 | 431 | * down_read(&EXT4_I(inode)->i_data_sem) |
ac27a0ec | 432 | */ |
725d26d3 AK |
433 | static Indirect *ext4_get_branch(struct inode *inode, int depth, |
434 | ext4_lblk_t *offsets, | |
ac27a0ec DK |
435 | Indirect chain[4], int *err) |
436 | { | |
437 | struct super_block *sb = inode->i_sb; | |
438 | Indirect *p = chain; | |
439 | struct buffer_head *bh; | |
440 | ||
441 | *err = 0; | |
442 | /* i_data is not going away, no lock needed */ | |
af5bc92d | 443 | add_chain(chain, NULL, EXT4_I(inode)->i_data + *offsets); |
ac27a0ec DK |
444 | if (!p->key) |
445 | goto no_block; | |
446 | while (--depth) { | |
fe2c8191 TN |
447 | bh = sb_getblk(sb, le32_to_cpu(p->key)); |
448 | if (unlikely(!bh)) | |
ac27a0ec | 449 | goto failure; |
fe2c8191 TN |
450 | |
451 | if (!bh_uptodate_or_lock(bh)) { | |
452 | if (bh_submit_read(bh) < 0) { | |
453 | put_bh(bh); | |
454 | goto failure; | |
455 | } | |
456 | /* validate block references */ | |
457 | if (ext4_check_indirect_blockref(inode, bh)) { | |
458 | put_bh(bh); | |
459 | goto failure; | |
460 | } | |
461 | } | |
462 | ||
af5bc92d | 463 | add_chain(++p, bh, (__le32 *)bh->b_data + *++offsets); |
ac27a0ec DK |
464 | /* Reader: end */ |
465 | if (!p->key) | |
466 | goto no_block; | |
467 | } | |
468 | return NULL; | |
469 | ||
ac27a0ec DK |
470 | failure: |
471 | *err = -EIO; | |
472 | no_block: | |
473 | return p; | |
474 | } | |
475 | ||
476 | /** | |
617ba13b | 477 | * ext4_find_near - find a place for allocation with sufficient locality |
ac27a0ec DK |
478 | * @inode: owner |
479 | * @ind: descriptor of indirect block. | |
480 | * | |
1cc8dcf5 | 481 | * This function returns the preferred place for block allocation. |
ac27a0ec DK |
482 | * It is used when heuristic for sequential allocation fails. |
483 | * Rules are: | |
484 | * + if there is a block to the left of our position - allocate near it. | |
485 | * + if pointer will live in indirect block - allocate near that block. | |
486 | * + if pointer will live in inode - allocate in the same | |
487 | * cylinder group. | |
488 | * | |
489 | * In the latter case we colour the starting block by the callers PID to | |
490 | * prevent it from clashing with concurrent allocations for a different inode | |
491 | * in the same block group. The PID is used here so that functionally related | |
492 | * files will be close-by on-disk. | |
493 | * | |
494 | * Caller must make sure that @ind is valid and will stay that way. | |
495 | */ | |
617ba13b | 496 | static ext4_fsblk_t ext4_find_near(struct inode *inode, Indirect *ind) |
ac27a0ec | 497 | { |
617ba13b | 498 | struct ext4_inode_info *ei = EXT4_I(inode); |
af5bc92d | 499 | __le32 *start = ind->bh ? (__le32 *) ind->bh->b_data : ei->i_data; |
ac27a0ec | 500 | __le32 *p; |
617ba13b | 501 | ext4_fsblk_t bg_start; |
74d3487f | 502 | ext4_fsblk_t last_block; |
617ba13b | 503 | ext4_grpblk_t colour; |
a4912123 TT |
504 | ext4_group_t block_group; |
505 | int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb)); | |
ac27a0ec DK |
506 | |
507 | /* Try to find previous block */ | |
508 | for (p = ind->p - 1; p >= start; p--) { | |
509 | if (*p) | |
510 | return le32_to_cpu(*p); | |
511 | } | |
512 | ||
513 | /* No such thing, so let's try location of indirect block */ | |
514 | if (ind->bh) | |
515 | return ind->bh->b_blocknr; | |
516 | ||
517 | /* | |
518 | * It is going to be referred to from the inode itself? OK, just put it | |
519 | * into the same cylinder group then. | |
520 | */ | |
a4912123 TT |
521 | block_group = ei->i_block_group; |
522 | if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) { | |
523 | block_group &= ~(flex_size-1); | |
524 | if (S_ISREG(inode->i_mode)) | |
525 | block_group++; | |
526 | } | |
527 | bg_start = ext4_group_first_block_no(inode->i_sb, block_group); | |
74d3487f VC |
528 | last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1; |
529 | ||
a4912123 TT |
530 | /* |
531 | * If we are doing delayed allocation, we don't need take | |
532 | * colour into account. | |
533 | */ | |
534 | if (test_opt(inode->i_sb, DELALLOC)) | |
535 | return bg_start; | |
536 | ||
74d3487f VC |
537 | if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block) |
538 | colour = (current->pid % 16) * | |
617ba13b | 539 | (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16); |
74d3487f VC |
540 | else |
541 | colour = (current->pid % 16) * ((last_block - bg_start) / 16); | |
ac27a0ec DK |
542 | return bg_start + colour; |
543 | } | |
544 | ||
545 | /** | |
1cc8dcf5 | 546 | * ext4_find_goal - find a preferred place for allocation. |
ac27a0ec DK |
547 | * @inode: owner |
548 | * @block: block we want | |
ac27a0ec | 549 | * @partial: pointer to the last triple within a chain |
ac27a0ec | 550 | * |
1cc8dcf5 | 551 | * Normally this function find the preferred place for block allocation, |
fb01bfda | 552 | * returns it. |
ac27a0ec | 553 | */ |
725d26d3 | 554 | static ext4_fsblk_t ext4_find_goal(struct inode *inode, ext4_lblk_t block, |
fb01bfda | 555 | Indirect *partial) |
ac27a0ec | 556 | { |
ac27a0ec | 557 | /* |
c2ea3fde | 558 | * XXX need to get goal block from mballoc's data structures |
ac27a0ec | 559 | */ |
ac27a0ec | 560 | |
617ba13b | 561 | return ext4_find_near(inode, partial); |
ac27a0ec DK |
562 | } |
563 | ||
564 | /** | |
617ba13b | 565 | * ext4_blks_to_allocate: Look up the block map and count the number |
ac27a0ec DK |
566 | * of direct blocks need to be allocated for the given branch. |
567 | * | |
568 | * @branch: chain of indirect blocks | |
569 | * @k: number of blocks need for indirect blocks | |
570 | * @blks: number of data blocks to be mapped. | |
571 | * @blocks_to_boundary: the offset in the indirect block | |
572 | * | |
573 | * return the total number of blocks to be allocate, including the | |
574 | * direct and indirect blocks. | |
575 | */ | |
498e5f24 | 576 | static int ext4_blks_to_allocate(Indirect *branch, int k, unsigned int blks, |
ac27a0ec DK |
577 | int blocks_to_boundary) |
578 | { | |
498e5f24 | 579 | unsigned int count = 0; |
ac27a0ec DK |
580 | |
581 | /* | |
582 | * Simple case, [t,d]Indirect block(s) has not allocated yet | |
583 | * then it's clear blocks on that path have not allocated | |
584 | */ | |
585 | if (k > 0) { | |
586 | /* right now we don't handle cross boundary allocation */ | |
587 | if (blks < blocks_to_boundary + 1) | |
588 | count += blks; | |
589 | else | |
590 | count += blocks_to_boundary + 1; | |
591 | return count; | |
592 | } | |
593 | ||
594 | count++; | |
595 | while (count < blks && count <= blocks_to_boundary && | |
596 | le32_to_cpu(*(branch[0].p + count)) == 0) { | |
597 | count++; | |
598 | } | |
599 | return count; | |
600 | } | |
601 | ||
602 | /** | |
617ba13b | 603 | * ext4_alloc_blocks: multiple allocate blocks needed for a branch |
ac27a0ec DK |
604 | * @indirect_blks: the number of blocks need to allocate for indirect |
605 | * blocks | |
606 | * | |
607 | * @new_blocks: on return it will store the new block numbers for | |
608 | * the indirect blocks(if needed) and the first direct block, | |
609 | * @blks: on return it will store the total number of allocated | |
610 | * direct blocks | |
611 | */ | |
617ba13b | 612 | static int ext4_alloc_blocks(handle_t *handle, struct inode *inode, |
7061eba7 AK |
613 | ext4_lblk_t iblock, ext4_fsblk_t goal, |
614 | int indirect_blks, int blks, | |
615 | ext4_fsblk_t new_blocks[4], int *err) | |
ac27a0ec | 616 | { |
815a1130 | 617 | struct ext4_allocation_request ar; |
ac27a0ec | 618 | int target, i; |
7061eba7 | 619 | unsigned long count = 0, blk_allocated = 0; |
ac27a0ec | 620 | int index = 0; |
617ba13b | 621 | ext4_fsblk_t current_block = 0; |
ac27a0ec DK |
622 | int ret = 0; |
623 | ||
624 | /* | |
625 | * Here we try to allocate the requested multiple blocks at once, | |
626 | * on a best-effort basis. | |
627 | * To build a branch, we should allocate blocks for | |
628 | * the indirect blocks(if not allocated yet), and at least | |
629 | * the first direct block of this branch. That's the | |
630 | * minimum number of blocks need to allocate(required) | |
631 | */ | |
7061eba7 AK |
632 | /* first we try to allocate the indirect blocks */ |
633 | target = indirect_blks; | |
634 | while (target > 0) { | |
ac27a0ec DK |
635 | count = target; |
636 | /* allocating blocks for indirect blocks and direct blocks */ | |
7061eba7 AK |
637 | current_block = ext4_new_meta_blocks(handle, inode, |
638 | goal, &count, err); | |
ac27a0ec DK |
639 | if (*err) |
640 | goto failed_out; | |
641 | ||
642 | target -= count; | |
643 | /* allocate blocks for indirect blocks */ | |
644 | while (index < indirect_blks && count) { | |
645 | new_blocks[index++] = current_block++; | |
646 | count--; | |
647 | } | |
7061eba7 AK |
648 | if (count > 0) { |
649 | /* | |
650 | * save the new block number | |
651 | * for the first direct block | |
652 | */ | |
653 | new_blocks[index] = current_block; | |
654 | printk(KERN_INFO "%s returned more blocks than " | |
655 | "requested\n", __func__); | |
656 | WARN_ON(1); | |
ac27a0ec | 657 | break; |
7061eba7 | 658 | } |
ac27a0ec DK |
659 | } |
660 | ||
7061eba7 AK |
661 | target = blks - count ; |
662 | blk_allocated = count; | |
663 | if (!target) | |
664 | goto allocated; | |
665 | /* Now allocate data blocks */ | |
815a1130 TT |
666 | memset(&ar, 0, sizeof(ar)); |
667 | ar.inode = inode; | |
668 | ar.goal = goal; | |
669 | ar.len = target; | |
670 | ar.logical = iblock; | |
671 | if (S_ISREG(inode->i_mode)) | |
672 | /* enable in-core preallocation only for regular files */ | |
673 | ar.flags = EXT4_MB_HINT_DATA; | |
674 | ||
675 | current_block = ext4_mb_new_blocks(handle, &ar, err); | |
676 | ||
7061eba7 AK |
677 | if (*err && (target == blks)) { |
678 | /* | |
679 | * if the allocation failed and we didn't allocate | |
680 | * any blocks before | |
681 | */ | |
682 | goto failed_out; | |
683 | } | |
684 | if (!*err) { | |
685 | if (target == blks) { | |
686 | /* | |
687 | * save the new block number | |
688 | * for the first direct block | |
689 | */ | |
690 | new_blocks[index] = current_block; | |
691 | } | |
815a1130 | 692 | blk_allocated += ar.len; |
7061eba7 AK |
693 | } |
694 | allocated: | |
ac27a0ec | 695 | /* total number of blocks allocated for direct blocks */ |
7061eba7 | 696 | ret = blk_allocated; |
ac27a0ec DK |
697 | *err = 0; |
698 | return ret; | |
699 | failed_out: | |
af5bc92d | 700 | for (i = 0; i < index; i++) |
c9de560d | 701 | ext4_free_blocks(handle, inode, new_blocks[i], 1, 0); |
ac27a0ec DK |
702 | return ret; |
703 | } | |
704 | ||
705 | /** | |
617ba13b | 706 | * ext4_alloc_branch - allocate and set up a chain of blocks. |
ac27a0ec DK |
707 | * @inode: owner |
708 | * @indirect_blks: number of allocated indirect blocks | |
709 | * @blks: number of allocated direct blocks | |
710 | * @offsets: offsets (in the blocks) to store the pointers to next. | |
711 | * @branch: place to store the chain in. | |
712 | * | |
713 | * This function allocates blocks, zeroes out all but the last one, | |
714 | * links them into chain and (if we are synchronous) writes them to disk. | |
715 | * In other words, it prepares a branch that can be spliced onto the | |
716 | * inode. It stores the information about that chain in the branch[], in | |
617ba13b | 717 | * the same format as ext4_get_branch() would do. We are calling it after |
ac27a0ec DK |
718 | * we had read the existing part of chain and partial points to the last |
719 | * triple of that (one with zero ->key). Upon the exit we have the same | |
617ba13b | 720 | * picture as after the successful ext4_get_block(), except that in one |
ac27a0ec DK |
721 | * place chain is disconnected - *branch->p is still zero (we did not |
722 | * set the last link), but branch->key contains the number that should | |
723 | * be placed into *branch->p to fill that gap. | |
724 | * | |
725 | * If allocation fails we free all blocks we've allocated (and forget | |
726 | * their buffer_heads) and return the error value the from failed | |
617ba13b | 727 | * ext4_alloc_block() (normally -ENOSPC). Otherwise we set the chain |
ac27a0ec DK |
728 | * as described above and return 0. |
729 | */ | |
617ba13b | 730 | static int ext4_alloc_branch(handle_t *handle, struct inode *inode, |
7061eba7 AK |
731 | ext4_lblk_t iblock, int indirect_blks, |
732 | int *blks, ext4_fsblk_t goal, | |
733 | ext4_lblk_t *offsets, Indirect *branch) | |
ac27a0ec DK |
734 | { |
735 | int blocksize = inode->i_sb->s_blocksize; | |
736 | int i, n = 0; | |
737 | int err = 0; | |
738 | struct buffer_head *bh; | |
739 | int num; | |
617ba13b MC |
740 | ext4_fsblk_t new_blocks[4]; |
741 | ext4_fsblk_t current_block; | |
ac27a0ec | 742 | |
7061eba7 | 743 | num = ext4_alloc_blocks(handle, inode, iblock, goal, indirect_blks, |
ac27a0ec DK |
744 | *blks, new_blocks, &err); |
745 | if (err) | |
746 | return err; | |
747 | ||
748 | branch[0].key = cpu_to_le32(new_blocks[0]); | |
749 | /* | |
750 | * metadata blocks and data blocks are allocated. | |
751 | */ | |
752 | for (n = 1; n <= indirect_blks; n++) { | |
753 | /* | |
754 | * Get buffer_head for parent block, zero it out | |
755 | * and set the pointer to new one, then send | |
756 | * parent to disk. | |
757 | */ | |
758 | bh = sb_getblk(inode->i_sb, new_blocks[n-1]); | |
759 | branch[n].bh = bh; | |
760 | lock_buffer(bh); | |
761 | BUFFER_TRACE(bh, "call get_create_access"); | |
617ba13b | 762 | err = ext4_journal_get_create_access(handle, bh); |
ac27a0ec DK |
763 | if (err) { |
764 | unlock_buffer(bh); | |
765 | brelse(bh); | |
766 | goto failed; | |
767 | } | |
768 | ||
769 | memset(bh->b_data, 0, blocksize); | |
770 | branch[n].p = (__le32 *) bh->b_data + offsets[n]; | |
771 | branch[n].key = cpu_to_le32(new_blocks[n]); | |
772 | *branch[n].p = branch[n].key; | |
af5bc92d | 773 | if (n == indirect_blks) { |
ac27a0ec DK |
774 | current_block = new_blocks[n]; |
775 | /* | |
776 | * End of chain, update the last new metablock of | |
777 | * the chain to point to the new allocated | |
778 | * data blocks numbers | |
779 | */ | |
780 | for (i=1; i < num; i++) | |
781 | *(branch[n].p + i) = cpu_to_le32(++current_block); | |
782 | } | |
783 | BUFFER_TRACE(bh, "marking uptodate"); | |
784 | set_buffer_uptodate(bh); | |
785 | unlock_buffer(bh); | |
786 | ||
0390131b FM |
787 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
788 | err = ext4_handle_dirty_metadata(handle, inode, bh); | |
ac27a0ec DK |
789 | if (err) |
790 | goto failed; | |
791 | } | |
792 | *blks = num; | |
793 | return err; | |
794 | failed: | |
795 | /* Allocation failed, free what we already allocated */ | |
796 | for (i = 1; i <= n ; i++) { | |
dab291af | 797 | BUFFER_TRACE(branch[i].bh, "call jbd2_journal_forget"); |
617ba13b | 798 | ext4_journal_forget(handle, branch[i].bh); |
ac27a0ec | 799 | } |
af5bc92d | 800 | for (i = 0; i < indirect_blks; i++) |
c9de560d | 801 | ext4_free_blocks(handle, inode, new_blocks[i], 1, 0); |
ac27a0ec | 802 | |
c9de560d | 803 | ext4_free_blocks(handle, inode, new_blocks[i], num, 0); |
ac27a0ec DK |
804 | |
805 | return err; | |
806 | } | |
807 | ||
808 | /** | |
617ba13b | 809 | * ext4_splice_branch - splice the allocated branch onto inode. |
ac27a0ec DK |
810 | * @inode: owner |
811 | * @block: (logical) number of block we are adding | |
812 | * @chain: chain of indirect blocks (with a missing link - see | |
617ba13b | 813 | * ext4_alloc_branch) |
ac27a0ec DK |
814 | * @where: location of missing link |
815 | * @num: number of indirect blocks we are adding | |
816 | * @blks: number of direct blocks we are adding | |
817 | * | |
818 | * This function fills the missing link and does all housekeeping needed in | |
819 | * inode (->i_blocks, etc.). In case of success we end up with the full | |
820 | * chain to new block and return 0. | |
821 | */ | |
617ba13b | 822 | static int ext4_splice_branch(handle_t *handle, struct inode *inode, |
725d26d3 | 823 | ext4_lblk_t block, Indirect *where, int num, int blks) |
ac27a0ec DK |
824 | { |
825 | int i; | |
826 | int err = 0; | |
617ba13b | 827 | ext4_fsblk_t current_block; |
ac27a0ec | 828 | |
ac27a0ec DK |
829 | /* |
830 | * If we're splicing into a [td]indirect block (as opposed to the | |
831 | * inode) then we need to get write access to the [td]indirect block | |
832 | * before the splice. | |
833 | */ | |
834 | if (where->bh) { | |
835 | BUFFER_TRACE(where->bh, "get_write_access"); | |
617ba13b | 836 | err = ext4_journal_get_write_access(handle, where->bh); |
ac27a0ec DK |
837 | if (err) |
838 | goto err_out; | |
839 | } | |
840 | /* That's it */ | |
841 | ||
842 | *where->p = where->key; | |
843 | ||
844 | /* | |
845 | * Update the host buffer_head or inode to point to more just allocated | |
846 | * direct blocks blocks | |
847 | */ | |
848 | if (num == 0 && blks > 1) { | |
849 | current_block = le32_to_cpu(where->key) + 1; | |
850 | for (i = 1; i < blks; i++) | |
af5bc92d | 851 | *(where->p + i) = cpu_to_le32(current_block++); |
ac27a0ec DK |
852 | } |
853 | ||
ac27a0ec DK |
854 | /* We are done with atomic stuff, now do the rest of housekeeping */ |
855 | ||
ef7f3835 | 856 | inode->i_ctime = ext4_current_time(inode); |
617ba13b | 857 | ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
858 | |
859 | /* had we spliced it onto indirect block? */ | |
860 | if (where->bh) { | |
861 | /* | |
862 | * If we spliced it onto an indirect block, we haven't | |
863 | * altered the inode. Note however that if it is being spliced | |
864 | * onto an indirect block at the very end of the file (the | |
865 | * file is growing) then we *will* alter the inode to reflect | |
866 | * the new i_size. But that is not done here - it is done in | |
617ba13b | 867 | * generic_commit_write->__mark_inode_dirty->ext4_dirty_inode. |
ac27a0ec DK |
868 | */ |
869 | jbd_debug(5, "splicing indirect only\n"); | |
0390131b FM |
870 | BUFFER_TRACE(where->bh, "call ext4_handle_dirty_metadata"); |
871 | err = ext4_handle_dirty_metadata(handle, inode, where->bh); | |
ac27a0ec DK |
872 | if (err) |
873 | goto err_out; | |
874 | } else { | |
875 | /* | |
876 | * OK, we spliced it into the inode itself on a direct block. | |
877 | * Inode was dirtied above. | |
878 | */ | |
879 | jbd_debug(5, "splicing direct\n"); | |
880 | } | |
881 | return err; | |
882 | ||
883 | err_out: | |
884 | for (i = 1; i <= num; i++) { | |
dab291af | 885 | BUFFER_TRACE(where[i].bh, "call jbd2_journal_forget"); |
617ba13b | 886 | ext4_journal_forget(handle, where[i].bh); |
c9de560d AT |
887 | ext4_free_blocks(handle, inode, |
888 | le32_to_cpu(where[i-1].key), 1, 0); | |
ac27a0ec | 889 | } |
c9de560d | 890 | ext4_free_blocks(handle, inode, le32_to_cpu(where[num].key), blks, 0); |
ac27a0ec DK |
891 | |
892 | return err; | |
893 | } | |
894 | ||
895 | /* | |
b920c755 TT |
896 | * The ext4_ind_get_blocks() function handles non-extents inodes |
897 | * (i.e., using the traditional indirect/double-indirect i_blocks | |
898 | * scheme) for ext4_get_blocks(). | |
899 | * | |
ac27a0ec DK |
900 | * Allocation strategy is simple: if we have to allocate something, we will |
901 | * have to go the whole way to leaf. So let's do it before attaching anything | |
902 | * to tree, set linkage between the newborn blocks, write them if sync is | |
903 | * required, recheck the path, free and repeat if check fails, otherwise | |
904 | * set the last missing link (that will protect us from any truncate-generated | |
905 | * removals - all blocks on the path are immune now) and possibly force the | |
906 | * write on the parent block. | |
907 | * That has a nice additional property: no special recovery from the failed | |
908 | * allocations is needed - we simply release blocks and do not touch anything | |
909 | * reachable from inode. | |
910 | * | |
911 | * `handle' can be NULL if create == 0. | |
912 | * | |
ac27a0ec DK |
913 | * return > 0, # of blocks mapped or allocated. |
914 | * return = 0, if plain lookup failed. | |
915 | * return < 0, error case. | |
c278bfec | 916 | * |
b920c755 TT |
917 | * The ext4_ind_get_blocks() function should be called with |
918 | * down_write(&EXT4_I(inode)->i_data_sem) if allocating filesystem | |
919 | * blocks (i.e., flags has EXT4_GET_BLOCKS_CREATE set) or | |
920 | * down_read(&EXT4_I(inode)->i_data_sem) if not allocating file system | |
921 | * blocks. | |
ac27a0ec | 922 | */ |
e4d996ca | 923 | static int ext4_ind_get_blocks(handle_t *handle, struct inode *inode, |
498e5f24 TT |
924 | ext4_lblk_t iblock, unsigned int maxblocks, |
925 | struct buffer_head *bh_result, | |
c2177057 | 926 | int flags) |
ac27a0ec DK |
927 | { |
928 | int err = -EIO; | |
725d26d3 | 929 | ext4_lblk_t offsets[4]; |
ac27a0ec DK |
930 | Indirect chain[4]; |
931 | Indirect *partial; | |
617ba13b | 932 | ext4_fsblk_t goal; |
ac27a0ec DK |
933 | int indirect_blks; |
934 | int blocks_to_boundary = 0; | |
935 | int depth; | |
ac27a0ec | 936 | int count = 0; |
617ba13b | 937 | ext4_fsblk_t first_block = 0; |
ac27a0ec | 938 | |
a86c6181 | 939 | J_ASSERT(!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)); |
c2177057 | 940 | J_ASSERT(handle != NULL || (flags & EXT4_GET_BLOCKS_CREATE) == 0); |
725d26d3 AK |
941 | depth = ext4_block_to_path(inode, iblock, offsets, |
942 | &blocks_to_boundary); | |
ac27a0ec DK |
943 | |
944 | if (depth == 0) | |
945 | goto out; | |
946 | ||
617ba13b | 947 | partial = ext4_get_branch(inode, depth, offsets, chain, &err); |
ac27a0ec DK |
948 | |
949 | /* Simplest case - block found, no allocation needed */ | |
950 | if (!partial) { | |
951 | first_block = le32_to_cpu(chain[depth - 1].key); | |
952 | clear_buffer_new(bh_result); | |
953 | count++; | |
954 | /*map more blocks*/ | |
955 | while (count < maxblocks && count <= blocks_to_boundary) { | |
617ba13b | 956 | ext4_fsblk_t blk; |
ac27a0ec | 957 | |
ac27a0ec DK |
958 | blk = le32_to_cpu(*(chain[depth-1].p + count)); |
959 | ||
960 | if (blk == first_block + count) | |
961 | count++; | |
962 | else | |
963 | break; | |
964 | } | |
c278bfec | 965 | goto got_it; |
ac27a0ec DK |
966 | } |
967 | ||
968 | /* Next simple case - plain lookup or failed read of indirect block */ | |
c2177057 | 969 | if ((flags & EXT4_GET_BLOCKS_CREATE) == 0 || err == -EIO) |
ac27a0ec DK |
970 | goto cleanup; |
971 | ||
ac27a0ec | 972 | /* |
c2ea3fde | 973 | * Okay, we need to do block allocation. |
ac27a0ec | 974 | */ |
fb01bfda | 975 | goal = ext4_find_goal(inode, iblock, partial); |
ac27a0ec DK |
976 | |
977 | /* the number of blocks need to allocate for [d,t]indirect blocks */ | |
978 | indirect_blks = (chain + depth) - partial - 1; | |
979 | ||
980 | /* | |
981 | * Next look up the indirect map to count the totoal number of | |
982 | * direct blocks to allocate for this branch. | |
983 | */ | |
617ba13b | 984 | count = ext4_blks_to_allocate(partial, indirect_blks, |
ac27a0ec DK |
985 | maxblocks, blocks_to_boundary); |
986 | /* | |
617ba13b | 987 | * Block out ext4_truncate while we alter the tree |
ac27a0ec | 988 | */ |
7061eba7 AK |
989 | err = ext4_alloc_branch(handle, inode, iblock, indirect_blks, |
990 | &count, goal, | |
991 | offsets + (partial - chain), partial); | |
ac27a0ec DK |
992 | |
993 | /* | |
617ba13b | 994 | * The ext4_splice_branch call will free and forget any buffers |
ac27a0ec DK |
995 | * on the new chain if there is a failure, but that risks using |
996 | * up transaction credits, especially for bitmaps where the | |
997 | * credits cannot be returned. Can we handle this somehow? We | |
998 | * may need to return -EAGAIN upwards in the worst case. --sct | |
999 | */ | |
1000 | if (!err) | |
617ba13b | 1001 | err = ext4_splice_branch(handle, inode, iblock, |
ac27a0ec | 1002 | partial, indirect_blks, count); |
03f5d8bc | 1003 | else |
ac27a0ec DK |
1004 | goto cleanup; |
1005 | ||
1006 | set_buffer_new(bh_result); | |
1007 | got_it: | |
1008 | map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key)); | |
1009 | if (count > blocks_to_boundary) | |
1010 | set_buffer_boundary(bh_result); | |
1011 | err = count; | |
1012 | /* Clean up and exit */ | |
1013 | partial = chain + depth - 1; /* the whole chain */ | |
1014 | cleanup: | |
1015 | while (partial > chain) { | |
1016 | BUFFER_TRACE(partial->bh, "call brelse"); | |
1017 | brelse(partial->bh); | |
1018 | partial--; | |
1019 | } | |
1020 | BUFFER_TRACE(bh_result, "returned"); | |
1021 | out: | |
1022 | return err; | |
1023 | } | |
1024 | ||
60e58e0f MC |
1025 | qsize_t ext4_get_reserved_space(struct inode *inode) |
1026 | { | |
1027 | unsigned long long total; | |
1028 | ||
1029 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); | |
1030 | total = EXT4_I(inode)->i_reserved_data_blocks + | |
1031 | EXT4_I(inode)->i_reserved_meta_blocks; | |
1032 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
1033 | ||
1034 | return total; | |
1035 | } | |
12219aea AK |
1036 | /* |
1037 | * Calculate the number of metadata blocks need to reserve | |
1038 | * to allocate @blocks for non extent file based file | |
1039 | */ | |
1040 | static int ext4_indirect_calc_metadata_amount(struct inode *inode, int blocks) | |
1041 | { | |
1042 | int icap = EXT4_ADDR_PER_BLOCK(inode->i_sb); | |
1043 | int ind_blks, dind_blks, tind_blks; | |
1044 | ||
1045 | /* number of new indirect blocks needed */ | |
1046 | ind_blks = (blocks + icap - 1) / icap; | |
1047 | ||
1048 | dind_blks = (ind_blks + icap - 1) / icap; | |
1049 | ||
1050 | tind_blks = 1; | |
1051 | ||
1052 | return ind_blks + dind_blks + tind_blks; | |
1053 | } | |
1054 | ||
1055 | /* | |
1056 | * Calculate the number of metadata blocks need to reserve | |
1057 | * to allocate given number of blocks | |
1058 | */ | |
1059 | static int ext4_calc_metadata_amount(struct inode *inode, int blocks) | |
1060 | { | |
cd213226 MC |
1061 | if (!blocks) |
1062 | return 0; | |
1063 | ||
12219aea AK |
1064 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) |
1065 | return ext4_ext_calc_metadata_amount(inode, blocks); | |
1066 | ||
1067 | return ext4_indirect_calc_metadata_amount(inode, blocks); | |
1068 | } | |
1069 | ||
1070 | static void ext4_da_update_reserve_space(struct inode *inode, int used) | |
1071 | { | |
1072 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
1073 | int total, mdb, mdb_free; | |
1074 | ||
1075 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); | |
1076 | /* recalculate the number of metablocks still need to be reserved */ | |
1077 | total = EXT4_I(inode)->i_reserved_data_blocks - used; | |
1078 | mdb = ext4_calc_metadata_amount(inode, total); | |
1079 | ||
1080 | /* figure out how many metablocks to release */ | |
1081 | BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks); | |
1082 | mdb_free = EXT4_I(inode)->i_reserved_meta_blocks - mdb; | |
1083 | ||
6bc6e63f AK |
1084 | if (mdb_free) { |
1085 | /* Account for allocated meta_blocks */ | |
1086 | mdb_free -= EXT4_I(inode)->i_allocated_meta_blocks; | |
1087 | ||
1088 | /* update fs dirty blocks counter */ | |
1089 | percpu_counter_sub(&sbi->s_dirtyblocks_counter, mdb_free); | |
1090 | EXT4_I(inode)->i_allocated_meta_blocks = 0; | |
1091 | EXT4_I(inode)->i_reserved_meta_blocks = mdb; | |
1092 | } | |
12219aea AK |
1093 | |
1094 | /* update per-inode reservations */ | |
1095 | BUG_ON(used > EXT4_I(inode)->i_reserved_data_blocks); | |
1096 | EXT4_I(inode)->i_reserved_data_blocks -= used; | |
12219aea | 1097 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
60e58e0f MC |
1098 | |
1099 | /* | |
1100 | * free those over-booking quota for metadata blocks | |
1101 | */ | |
60e58e0f MC |
1102 | if (mdb_free) |
1103 | vfs_dq_release_reservation_block(inode, mdb_free); | |
d6014301 AK |
1104 | |
1105 | /* | |
1106 | * If we have done all the pending block allocations and if | |
1107 | * there aren't any writers on the inode, we can discard the | |
1108 | * inode's preallocations. | |
1109 | */ | |
1110 | if (!total && (atomic_read(&inode->i_writecount) == 0)) | |
1111 | ext4_discard_preallocations(inode); | |
12219aea AK |
1112 | } |
1113 | ||
6fd058f7 TT |
1114 | static int check_block_validity(struct inode *inode, sector_t logical, |
1115 | sector_t phys, int len) | |
1116 | { | |
1117 | if (!ext4_data_block_valid(EXT4_SB(inode->i_sb), phys, len)) { | |
1118 | ext4_error(inode->i_sb, "check_block_validity", | |
1119 | "inode #%lu logical block %llu mapped to %llu " | |
1120 | "(size %d)", inode->i_ino, | |
1121 | (unsigned long long) logical, | |
1122 | (unsigned long long) phys, len); | |
1123 | WARN_ON(1); | |
1124 | return -EIO; | |
1125 | } | |
1126 | return 0; | |
1127 | } | |
1128 | ||
f5ab0d1f | 1129 | /* |
12b7ac17 | 1130 | * The ext4_get_blocks() function tries to look up the requested blocks, |
2b2d6d01 | 1131 | * and returns if the blocks are already mapped. |
f5ab0d1f | 1132 | * |
f5ab0d1f MC |
1133 | * Otherwise it takes the write lock of the i_data_sem and allocate blocks |
1134 | * and store the allocated blocks in the result buffer head and mark it | |
1135 | * mapped. | |
1136 | * | |
1137 | * If file type is extents based, it will call ext4_ext_get_blocks(), | |
e4d996ca | 1138 | * Otherwise, call with ext4_ind_get_blocks() to handle indirect mapping |
f5ab0d1f MC |
1139 | * based files |
1140 | * | |
1141 | * On success, it returns the number of blocks being mapped or allocate. | |
1142 | * if create==0 and the blocks are pre-allocated and uninitialized block, | |
1143 | * the result buffer head is unmapped. If the create ==1, it will make sure | |
1144 | * the buffer head is mapped. | |
1145 | * | |
1146 | * It returns 0 if plain look up failed (blocks have not been allocated), in | |
1147 | * that casem, buffer head is unmapped | |
1148 | * | |
1149 | * It returns the error in case of allocation failure. | |
1150 | */ | |
12b7ac17 TT |
1151 | int ext4_get_blocks(handle_t *handle, struct inode *inode, sector_t block, |
1152 | unsigned int max_blocks, struct buffer_head *bh, | |
c2177057 | 1153 | int flags) |
0e855ac8 AK |
1154 | { |
1155 | int retval; | |
f5ab0d1f MC |
1156 | |
1157 | clear_buffer_mapped(bh); | |
2a8964d6 | 1158 | clear_buffer_unwritten(bh); |
f5ab0d1f | 1159 | |
4df3d265 | 1160 | /* |
b920c755 TT |
1161 | * Try to see if we can get the block without requesting a new |
1162 | * file system block. | |
4df3d265 AK |
1163 | */ |
1164 | down_read((&EXT4_I(inode)->i_data_sem)); | |
1165 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { | |
1166 | retval = ext4_ext_get_blocks(handle, inode, block, max_blocks, | |
c2177057 | 1167 | bh, 0); |
0e855ac8 | 1168 | } else { |
e4d996ca | 1169 | retval = ext4_ind_get_blocks(handle, inode, block, max_blocks, |
c2177057 | 1170 | bh, 0); |
0e855ac8 | 1171 | } |
4df3d265 | 1172 | up_read((&EXT4_I(inode)->i_data_sem)); |
f5ab0d1f | 1173 | |
6fd058f7 TT |
1174 | if (retval > 0 && buffer_mapped(bh)) { |
1175 | int ret = check_block_validity(inode, block, | |
1176 | bh->b_blocknr, retval); | |
1177 | if (ret != 0) | |
1178 | return ret; | |
1179 | } | |
1180 | ||
f5ab0d1f | 1181 | /* If it is only a block(s) look up */ |
c2177057 | 1182 | if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) |
f5ab0d1f MC |
1183 | return retval; |
1184 | ||
1185 | /* | |
1186 | * Returns if the blocks have already allocated | |
1187 | * | |
1188 | * Note that if blocks have been preallocated | |
1189 | * ext4_ext_get_block() returns th create = 0 | |
1190 | * with buffer head unmapped. | |
1191 | */ | |
1192 | if (retval > 0 && buffer_mapped(bh)) | |
4df3d265 AK |
1193 | return retval; |
1194 | ||
2a8964d6 AK |
1195 | /* |
1196 | * When we call get_blocks without the create flag, the | |
1197 | * BH_Unwritten flag could have gotten set if the blocks | |
1198 | * requested were part of a uninitialized extent. We need to | |
1199 | * clear this flag now that we are committed to convert all or | |
1200 | * part of the uninitialized extent to be an initialized | |
1201 | * extent. This is because we need to avoid the combination | |
1202 | * of BH_Unwritten and BH_Mapped flags being simultaneously | |
1203 | * set on the buffer_head. | |
1204 | */ | |
1205 | clear_buffer_unwritten(bh); | |
1206 | ||
4df3d265 | 1207 | /* |
f5ab0d1f MC |
1208 | * New blocks allocate and/or writing to uninitialized extent |
1209 | * will possibly result in updating i_data, so we take | |
1210 | * the write lock of i_data_sem, and call get_blocks() | |
1211 | * with create == 1 flag. | |
4df3d265 AK |
1212 | */ |
1213 | down_write((&EXT4_I(inode)->i_data_sem)); | |
d2a17637 MC |
1214 | |
1215 | /* | |
1216 | * if the caller is from delayed allocation writeout path | |
1217 | * we have already reserved fs blocks for allocation | |
1218 | * let the underlying get_block() function know to | |
1219 | * avoid double accounting | |
1220 | */ | |
c2177057 | 1221 | if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) |
d2a17637 | 1222 | EXT4_I(inode)->i_delalloc_reserved_flag = 1; |
4df3d265 AK |
1223 | /* |
1224 | * We need to check for EXT4 here because migrate | |
1225 | * could have changed the inode type in between | |
1226 | */ | |
0e855ac8 AK |
1227 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { |
1228 | retval = ext4_ext_get_blocks(handle, inode, block, max_blocks, | |
c2177057 | 1229 | bh, flags); |
0e855ac8 | 1230 | } else { |
e4d996ca | 1231 | retval = ext4_ind_get_blocks(handle, inode, block, |
c2177057 | 1232 | max_blocks, bh, flags); |
267e4db9 AK |
1233 | |
1234 | if (retval > 0 && buffer_new(bh)) { | |
1235 | /* | |
1236 | * We allocated new blocks which will result in | |
1237 | * i_data's format changing. Force the migrate | |
1238 | * to fail by clearing migrate flags | |
1239 | */ | |
1240 | EXT4_I(inode)->i_flags = EXT4_I(inode)->i_flags & | |
1241 | ~EXT4_EXT_MIGRATE; | |
1242 | } | |
0e855ac8 | 1243 | } |
d2a17637 | 1244 | |
2ac3b6e0 | 1245 | if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) |
d2a17637 | 1246 | EXT4_I(inode)->i_delalloc_reserved_flag = 0; |
2ac3b6e0 TT |
1247 | |
1248 | /* | |
1249 | * Update reserved blocks/metadata blocks after successful | |
1250 | * block allocation which had been deferred till now. | |
1251 | */ | |
1252 | if ((retval > 0) && (flags & EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE)) | |
1253 | ext4_da_update_reserve_space(inode, retval); | |
d2a17637 | 1254 | |
4df3d265 | 1255 | up_write((&EXT4_I(inode)->i_data_sem)); |
6fd058f7 TT |
1256 | if (retval > 0 && buffer_mapped(bh)) { |
1257 | int ret = check_block_validity(inode, block, | |
1258 | bh->b_blocknr, retval); | |
1259 | if (ret != 0) | |
1260 | return ret; | |
1261 | } | |
0e855ac8 AK |
1262 | return retval; |
1263 | } | |
1264 | ||
f3bd1f3f MC |
1265 | /* Maximum number of blocks we map for direct IO at once. */ |
1266 | #define DIO_MAX_BLOCKS 4096 | |
1267 | ||
6873fa0d ES |
1268 | int ext4_get_block(struct inode *inode, sector_t iblock, |
1269 | struct buffer_head *bh_result, int create) | |
ac27a0ec | 1270 | { |
3e4fdaf8 | 1271 | handle_t *handle = ext4_journal_current_handle(); |
7fb5409d | 1272 | int ret = 0, started = 0; |
ac27a0ec | 1273 | unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; |
f3bd1f3f | 1274 | int dio_credits; |
ac27a0ec | 1275 | |
7fb5409d JK |
1276 | if (create && !handle) { |
1277 | /* Direct IO write... */ | |
1278 | if (max_blocks > DIO_MAX_BLOCKS) | |
1279 | max_blocks = DIO_MAX_BLOCKS; | |
f3bd1f3f MC |
1280 | dio_credits = ext4_chunk_trans_blocks(inode, max_blocks); |
1281 | handle = ext4_journal_start(inode, dio_credits); | |
7fb5409d | 1282 | if (IS_ERR(handle)) { |
ac27a0ec | 1283 | ret = PTR_ERR(handle); |
7fb5409d | 1284 | goto out; |
ac27a0ec | 1285 | } |
7fb5409d | 1286 | started = 1; |
ac27a0ec DK |
1287 | } |
1288 | ||
12b7ac17 | 1289 | ret = ext4_get_blocks(handle, inode, iblock, max_blocks, bh_result, |
c2177057 | 1290 | create ? EXT4_GET_BLOCKS_CREATE : 0); |
7fb5409d JK |
1291 | if (ret > 0) { |
1292 | bh_result->b_size = (ret << inode->i_blkbits); | |
1293 | ret = 0; | |
ac27a0ec | 1294 | } |
7fb5409d JK |
1295 | if (started) |
1296 | ext4_journal_stop(handle); | |
1297 | out: | |
ac27a0ec DK |
1298 | return ret; |
1299 | } | |
1300 | ||
1301 | /* | |
1302 | * `handle' can be NULL if create is zero | |
1303 | */ | |
617ba13b | 1304 | struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode, |
725d26d3 | 1305 | ext4_lblk_t block, int create, int *errp) |
ac27a0ec DK |
1306 | { |
1307 | struct buffer_head dummy; | |
1308 | int fatal = 0, err; | |
03f5d8bc | 1309 | int flags = 0; |
ac27a0ec DK |
1310 | |
1311 | J_ASSERT(handle != NULL || create == 0); | |
1312 | ||
1313 | dummy.b_state = 0; | |
1314 | dummy.b_blocknr = -1000; | |
1315 | buffer_trace_init(&dummy.b_history); | |
c2177057 TT |
1316 | if (create) |
1317 | flags |= EXT4_GET_BLOCKS_CREATE; | |
1318 | err = ext4_get_blocks(handle, inode, block, 1, &dummy, flags); | |
ac27a0ec | 1319 | /* |
c2177057 TT |
1320 | * ext4_get_blocks() returns number of blocks mapped. 0 in |
1321 | * case of a HOLE. | |
ac27a0ec DK |
1322 | */ |
1323 | if (err > 0) { | |
1324 | if (err > 1) | |
1325 | WARN_ON(1); | |
1326 | err = 0; | |
1327 | } | |
1328 | *errp = err; | |
1329 | if (!err && buffer_mapped(&dummy)) { | |
1330 | struct buffer_head *bh; | |
1331 | bh = sb_getblk(inode->i_sb, dummy.b_blocknr); | |
1332 | if (!bh) { | |
1333 | *errp = -EIO; | |
1334 | goto err; | |
1335 | } | |
1336 | if (buffer_new(&dummy)) { | |
1337 | J_ASSERT(create != 0); | |
ac39849d | 1338 | J_ASSERT(handle != NULL); |
ac27a0ec DK |
1339 | |
1340 | /* | |
1341 | * Now that we do not always journal data, we should | |
1342 | * keep in mind whether this should always journal the | |
1343 | * new buffer as metadata. For now, regular file | |
617ba13b | 1344 | * writes use ext4_get_block instead, so it's not a |
ac27a0ec DK |
1345 | * problem. |
1346 | */ | |
1347 | lock_buffer(bh); | |
1348 | BUFFER_TRACE(bh, "call get_create_access"); | |
617ba13b | 1349 | fatal = ext4_journal_get_create_access(handle, bh); |
ac27a0ec | 1350 | if (!fatal && !buffer_uptodate(bh)) { |
af5bc92d | 1351 | memset(bh->b_data, 0, inode->i_sb->s_blocksize); |
ac27a0ec DK |
1352 | set_buffer_uptodate(bh); |
1353 | } | |
1354 | unlock_buffer(bh); | |
0390131b FM |
1355 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
1356 | err = ext4_handle_dirty_metadata(handle, inode, bh); | |
ac27a0ec DK |
1357 | if (!fatal) |
1358 | fatal = err; | |
1359 | } else { | |
1360 | BUFFER_TRACE(bh, "not a new buffer"); | |
1361 | } | |
1362 | if (fatal) { | |
1363 | *errp = fatal; | |
1364 | brelse(bh); | |
1365 | bh = NULL; | |
1366 | } | |
1367 | return bh; | |
1368 | } | |
1369 | err: | |
1370 | return NULL; | |
1371 | } | |
1372 | ||
617ba13b | 1373 | struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode, |
725d26d3 | 1374 | ext4_lblk_t block, int create, int *err) |
ac27a0ec | 1375 | { |
af5bc92d | 1376 | struct buffer_head *bh; |
ac27a0ec | 1377 | |
617ba13b | 1378 | bh = ext4_getblk(handle, inode, block, create, err); |
ac27a0ec DK |
1379 | if (!bh) |
1380 | return bh; | |
1381 | if (buffer_uptodate(bh)) | |
1382 | return bh; | |
1383 | ll_rw_block(READ_META, 1, &bh); | |
1384 | wait_on_buffer(bh); | |
1385 | if (buffer_uptodate(bh)) | |
1386 | return bh; | |
1387 | put_bh(bh); | |
1388 | *err = -EIO; | |
1389 | return NULL; | |
1390 | } | |
1391 | ||
af5bc92d TT |
1392 | static int walk_page_buffers(handle_t *handle, |
1393 | struct buffer_head *head, | |
1394 | unsigned from, | |
1395 | unsigned to, | |
1396 | int *partial, | |
1397 | int (*fn)(handle_t *handle, | |
1398 | struct buffer_head *bh)) | |
ac27a0ec DK |
1399 | { |
1400 | struct buffer_head *bh; | |
1401 | unsigned block_start, block_end; | |
1402 | unsigned blocksize = head->b_size; | |
1403 | int err, ret = 0; | |
1404 | struct buffer_head *next; | |
1405 | ||
af5bc92d TT |
1406 | for (bh = head, block_start = 0; |
1407 | ret == 0 && (bh != head || !block_start); | |
1408 | block_start = block_end, bh = next) | |
ac27a0ec DK |
1409 | { |
1410 | next = bh->b_this_page; | |
1411 | block_end = block_start + blocksize; | |
1412 | if (block_end <= from || block_start >= to) { | |
1413 | if (partial && !buffer_uptodate(bh)) | |
1414 | *partial = 1; | |
1415 | continue; | |
1416 | } | |
1417 | err = (*fn)(handle, bh); | |
1418 | if (!ret) | |
1419 | ret = err; | |
1420 | } | |
1421 | return ret; | |
1422 | } | |
1423 | ||
1424 | /* | |
1425 | * To preserve ordering, it is essential that the hole instantiation and | |
1426 | * the data write be encapsulated in a single transaction. We cannot | |
617ba13b | 1427 | * close off a transaction and start a new one between the ext4_get_block() |
dab291af | 1428 | * and the commit_write(). So doing the jbd2_journal_start at the start of |
ac27a0ec DK |
1429 | * prepare_write() is the right place. |
1430 | * | |
617ba13b MC |
1431 | * Also, this function can nest inside ext4_writepage() -> |
1432 | * block_write_full_page(). In that case, we *know* that ext4_writepage() | |
ac27a0ec DK |
1433 | * has generated enough buffer credits to do the whole page. So we won't |
1434 | * block on the journal in that case, which is good, because the caller may | |
1435 | * be PF_MEMALLOC. | |
1436 | * | |
617ba13b | 1437 | * By accident, ext4 can be reentered when a transaction is open via |
ac27a0ec DK |
1438 | * quota file writes. If we were to commit the transaction while thus |
1439 | * reentered, there can be a deadlock - we would be holding a quota | |
1440 | * lock, and the commit would never complete if another thread had a | |
1441 | * transaction open and was blocking on the quota lock - a ranking | |
1442 | * violation. | |
1443 | * | |
dab291af | 1444 | * So what we do is to rely on the fact that jbd2_journal_stop/journal_start |
ac27a0ec DK |
1445 | * will _not_ run commit under these circumstances because handle->h_ref |
1446 | * is elevated. We'll still have enough credits for the tiny quotafile | |
1447 | * write. | |
1448 | */ | |
1449 | static int do_journal_get_write_access(handle_t *handle, | |
1450 | struct buffer_head *bh) | |
1451 | { | |
1452 | if (!buffer_mapped(bh) || buffer_freed(bh)) | |
1453 | return 0; | |
617ba13b | 1454 | return ext4_journal_get_write_access(handle, bh); |
ac27a0ec DK |
1455 | } |
1456 | ||
bfc1af65 NP |
1457 | static int ext4_write_begin(struct file *file, struct address_space *mapping, |
1458 | loff_t pos, unsigned len, unsigned flags, | |
1459 | struct page **pagep, void **fsdata) | |
ac27a0ec | 1460 | { |
af5bc92d | 1461 | struct inode *inode = mapping->host; |
1938a150 | 1462 | int ret, needed_blocks; |
ac27a0ec DK |
1463 | handle_t *handle; |
1464 | int retries = 0; | |
af5bc92d | 1465 | struct page *page; |
bfc1af65 | 1466 | pgoff_t index; |
af5bc92d | 1467 | unsigned from, to; |
bfc1af65 | 1468 | |
ba80b101 TT |
1469 | trace_mark(ext4_write_begin, |
1470 | "dev %s ino %lu pos %llu len %u flags %u", | |
1471 | inode->i_sb->s_id, inode->i_ino, | |
1472 | (unsigned long long) pos, len, flags); | |
1938a150 AK |
1473 | /* |
1474 | * Reserve one block more for addition to orphan list in case | |
1475 | * we allocate blocks but write fails for some reason | |
1476 | */ | |
1477 | needed_blocks = ext4_writepage_trans_blocks(inode) + 1; | |
bfc1af65 | 1478 | index = pos >> PAGE_CACHE_SHIFT; |
af5bc92d TT |
1479 | from = pos & (PAGE_CACHE_SIZE - 1); |
1480 | to = from + len; | |
ac27a0ec DK |
1481 | |
1482 | retry: | |
af5bc92d TT |
1483 | handle = ext4_journal_start(inode, needed_blocks); |
1484 | if (IS_ERR(handle)) { | |
1485 | ret = PTR_ERR(handle); | |
1486 | goto out; | |
7479d2b9 | 1487 | } |
ac27a0ec | 1488 | |
ebd3610b JK |
1489 | /* We cannot recurse into the filesystem as the transaction is already |
1490 | * started */ | |
1491 | flags |= AOP_FLAG_NOFS; | |
1492 | ||
54566b2c | 1493 | page = grab_cache_page_write_begin(mapping, index, flags); |
cf108bca JK |
1494 | if (!page) { |
1495 | ext4_journal_stop(handle); | |
1496 | ret = -ENOMEM; | |
1497 | goto out; | |
1498 | } | |
1499 | *pagep = page; | |
1500 | ||
bfc1af65 | 1501 | ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, |
ebd3610b | 1502 | ext4_get_block); |
bfc1af65 NP |
1503 | |
1504 | if (!ret && ext4_should_journal_data(inode)) { | |
ac27a0ec DK |
1505 | ret = walk_page_buffers(handle, page_buffers(page), |
1506 | from, to, NULL, do_journal_get_write_access); | |
1507 | } | |
bfc1af65 NP |
1508 | |
1509 | if (ret) { | |
af5bc92d | 1510 | unlock_page(page); |
af5bc92d | 1511 | page_cache_release(page); |
ae4d5372 AK |
1512 | /* |
1513 | * block_write_begin may have instantiated a few blocks | |
1514 | * outside i_size. Trim these off again. Don't need | |
1515 | * i_size_read because we hold i_mutex. | |
1938a150 AK |
1516 | * |
1517 | * Add inode to orphan list in case we crash before | |
1518 | * truncate finishes | |
ae4d5372 AK |
1519 | */ |
1520 | if (pos + len > inode->i_size) | |
1938a150 AK |
1521 | ext4_orphan_add(handle, inode); |
1522 | ||
1523 | ext4_journal_stop(handle); | |
1524 | if (pos + len > inode->i_size) { | |
ae4d5372 | 1525 | vmtruncate(inode, inode->i_size); |
1938a150 AK |
1526 | /* |
1527 | * If vmtruncate failed early the inode might | |
1528 | * still be on the orphan list; we need to | |
1529 | * make sure the inode is removed from the | |
1530 | * orphan list in that case. | |
1531 | */ | |
1532 | if (inode->i_nlink) | |
1533 | ext4_orphan_del(NULL, inode); | |
1534 | } | |
bfc1af65 NP |
1535 | } |
1536 | ||
617ba13b | 1537 | if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) |
ac27a0ec | 1538 | goto retry; |
7479d2b9 | 1539 | out: |
ac27a0ec DK |
1540 | return ret; |
1541 | } | |
1542 | ||
bfc1af65 NP |
1543 | /* For write_end() in data=journal mode */ |
1544 | static int write_end_fn(handle_t *handle, struct buffer_head *bh) | |
ac27a0ec DK |
1545 | { |
1546 | if (!buffer_mapped(bh) || buffer_freed(bh)) | |
1547 | return 0; | |
1548 | set_buffer_uptodate(bh); | |
0390131b | 1549 | return ext4_handle_dirty_metadata(handle, NULL, bh); |
ac27a0ec DK |
1550 | } |
1551 | ||
f8514083 AK |
1552 | static int ext4_generic_write_end(struct file *file, |
1553 | struct address_space *mapping, | |
1554 | loff_t pos, unsigned len, unsigned copied, | |
1555 | struct page *page, void *fsdata) | |
1556 | { | |
1557 | int i_size_changed = 0; | |
1558 | struct inode *inode = mapping->host; | |
1559 | handle_t *handle = ext4_journal_current_handle(); | |
1560 | ||
1561 | copied = block_write_end(file, mapping, pos, len, copied, page, fsdata); | |
1562 | ||
1563 | /* | |
1564 | * No need to use i_size_read() here, the i_size | |
1565 | * cannot change under us because we hold i_mutex. | |
1566 | * | |
1567 | * But it's important to update i_size while still holding page lock: | |
1568 | * page writeout could otherwise come in and zero beyond i_size. | |
1569 | */ | |
1570 | if (pos + copied > inode->i_size) { | |
1571 | i_size_write(inode, pos + copied); | |
1572 | i_size_changed = 1; | |
1573 | } | |
1574 | ||
1575 | if (pos + copied > EXT4_I(inode)->i_disksize) { | |
1576 | /* We need to mark inode dirty even if | |
1577 | * new_i_size is less that inode->i_size | |
1578 | * bu greater than i_disksize.(hint delalloc) | |
1579 | */ | |
1580 | ext4_update_i_disksize(inode, (pos + copied)); | |
1581 | i_size_changed = 1; | |
1582 | } | |
1583 | unlock_page(page); | |
1584 | page_cache_release(page); | |
1585 | ||
1586 | /* | |
1587 | * Don't mark the inode dirty under page lock. First, it unnecessarily | |
1588 | * makes the holding time of page lock longer. Second, it forces lock | |
1589 | * ordering of page lock and transaction start for journaling | |
1590 | * filesystems. | |
1591 | */ | |
1592 | if (i_size_changed) | |
1593 | ext4_mark_inode_dirty(handle, inode); | |
1594 | ||
1595 | return copied; | |
1596 | } | |
1597 | ||
ac27a0ec DK |
1598 | /* |
1599 | * We need to pick up the new inode size which generic_commit_write gave us | |
1600 | * `file' can be NULL - eg, when called from page_symlink(). | |
1601 | * | |
617ba13b | 1602 | * ext4 never places buffers on inode->i_mapping->private_list. metadata |
ac27a0ec DK |
1603 | * buffers are managed internally. |
1604 | */ | |
bfc1af65 NP |
1605 | static int ext4_ordered_write_end(struct file *file, |
1606 | struct address_space *mapping, | |
1607 | loff_t pos, unsigned len, unsigned copied, | |
1608 | struct page *page, void *fsdata) | |
ac27a0ec | 1609 | { |
617ba13b | 1610 | handle_t *handle = ext4_journal_current_handle(); |
cf108bca | 1611 | struct inode *inode = mapping->host; |
ac27a0ec DK |
1612 | int ret = 0, ret2; |
1613 | ||
ba80b101 TT |
1614 | trace_mark(ext4_ordered_write_end, |
1615 | "dev %s ino %lu pos %llu len %u copied %u", | |
1616 | inode->i_sb->s_id, inode->i_ino, | |
1617 | (unsigned long long) pos, len, copied); | |
678aaf48 | 1618 | ret = ext4_jbd2_file_inode(handle, inode); |
ac27a0ec DK |
1619 | |
1620 | if (ret == 0) { | |
f8514083 | 1621 | ret2 = ext4_generic_write_end(file, mapping, pos, len, copied, |
bfc1af65 | 1622 | page, fsdata); |
f8a87d89 | 1623 | copied = ret2; |
f8514083 AK |
1624 | if (pos + len > inode->i_size) |
1625 | /* if we have allocated more blocks and copied | |
1626 | * less. We will have blocks allocated outside | |
1627 | * inode->i_size. So truncate them | |
1628 | */ | |
1629 | ext4_orphan_add(handle, inode); | |
f8a87d89 RK |
1630 | if (ret2 < 0) |
1631 | ret = ret2; | |
ac27a0ec | 1632 | } |
617ba13b | 1633 | ret2 = ext4_journal_stop(handle); |
ac27a0ec DK |
1634 | if (!ret) |
1635 | ret = ret2; | |
bfc1af65 | 1636 | |
f8514083 AK |
1637 | if (pos + len > inode->i_size) { |
1638 | vmtruncate(inode, inode->i_size); | |
1639 | /* | |
1640 | * If vmtruncate failed early the inode might still be | |
1641 | * on the orphan list; we need to make sure the inode | |
1642 | * is removed from the orphan list in that case. | |
1643 | */ | |
1644 | if (inode->i_nlink) | |
1645 | ext4_orphan_del(NULL, inode); | |
1646 | } | |
1647 | ||
1648 | ||
bfc1af65 | 1649 | return ret ? ret : copied; |
ac27a0ec DK |
1650 | } |
1651 | ||
bfc1af65 NP |
1652 | static int ext4_writeback_write_end(struct file *file, |
1653 | struct address_space *mapping, | |
1654 | loff_t pos, unsigned len, unsigned copied, | |
1655 | struct page *page, void *fsdata) | |
ac27a0ec | 1656 | { |
617ba13b | 1657 | handle_t *handle = ext4_journal_current_handle(); |
cf108bca | 1658 | struct inode *inode = mapping->host; |
ac27a0ec | 1659 | int ret = 0, ret2; |
ac27a0ec | 1660 | |
ba80b101 TT |
1661 | trace_mark(ext4_writeback_write_end, |
1662 | "dev %s ino %lu pos %llu len %u copied %u", | |
1663 | inode->i_sb->s_id, inode->i_ino, | |
1664 | (unsigned long long) pos, len, copied); | |
f8514083 | 1665 | ret2 = ext4_generic_write_end(file, mapping, pos, len, copied, |
bfc1af65 | 1666 | page, fsdata); |
f8a87d89 | 1667 | copied = ret2; |
f8514083 AK |
1668 | if (pos + len > inode->i_size) |
1669 | /* if we have allocated more blocks and copied | |
1670 | * less. We will have blocks allocated outside | |
1671 | * inode->i_size. So truncate them | |
1672 | */ | |
1673 | ext4_orphan_add(handle, inode); | |
1674 | ||
f8a87d89 RK |
1675 | if (ret2 < 0) |
1676 | ret = ret2; | |
ac27a0ec | 1677 | |
617ba13b | 1678 | ret2 = ext4_journal_stop(handle); |
ac27a0ec DK |
1679 | if (!ret) |
1680 | ret = ret2; | |
bfc1af65 | 1681 | |
f8514083 AK |
1682 | if (pos + len > inode->i_size) { |
1683 | vmtruncate(inode, inode->i_size); | |
1684 | /* | |
1685 | * If vmtruncate failed early the inode might still be | |
1686 | * on the orphan list; we need to make sure the inode | |
1687 | * is removed from the orphan list in that case. | |
1688 | */ | |
1689 | if (inode->i_nlink) | |
1690 | ext4_orphan_del(NULL, inode); | |
1691 | } | |
1692 | ||
bfc1af65 | 1693 | return ret ? ret : copied; |
ac27a0ec DK |
1694 | } |
1695 | ||
bfc1af65 NP |
1696 | static int ext4_journalled_write_end(struct file *file, |
1697 | struct address_space *mapping, | |
1698 | loff_t pos, unsigned len, unsigned copied, | |
1699 | struct page *page, void *fsdata) | |
ac27a0ec | 1700 | { |
617ba13b | 1701 | handle_t *handle = ext4_journal_current_handle(); |
bfc1af65 | 1702 | struct inode *inode = mapping->host; |
ac27a0ec DK |
1703 | int ret = 0, ret2; |
1704 | int partial = 0; | |
bfc1af65 | 1705 | unsigned from, to; |
cf17fea6 | 1706 | loff_t new_i_size; |
ac27a0ec | 1707 | |
ba80b101 TT |
1708 | trace_mark(ext4_journalled_write_end, |
1709 | "dev %s ino %lu pos %llu len %u copied %u", | |
1710 | inode->i_sb->s_id, inode->i_ino, | |
1711 | (unsigned long long) pos, len, copied); | |
bfc1af65 NP |
1712 | from = pos & (PAGE_CACHE_SIZE - 1); |
1713 | to = from + len; | |
1714 | ||
1715 | if (copied < len) { | |
1716 | if (!PageUptodate(page)) | |
1717 | copied = 0; | |
1718 | page_zero_new_buffers(page, from+copied, to); | |
1719 | } | |
ac27a0ec DK |
1720 | |
1721 | ret = walk_page_buffers(handle, page_buffers(page), from, | |
bfc1af65 | 1722 | to, &partial, write_end_fn); |
ac27a0ec DK |
1723 | if (!partial) |
1724 | SetPageUptodate(page); | |
cf17fea6 AK |
1725 | new_i_size = pos + copied; |
1726 | if (new_i_size > inode->i_size) | |
bfc1af65 | 1727 | i_size_write(inode, pos+copied); |
617ba13b | 1728 | EXT4_I(inode)->i_state |= EXT4_STATE_JDATA; |
cf17fea6 AK |
1729 | if (new_i_size > EXT4_I(inode)->i_disksize) { |
1730 | ext4_update_i_disksize(inode, new_i_size); | |
617ba13b | 1731 | ret2 = ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
1732 | if (!ret) |
1733 | ret = ret2; | |
1734 | } | |
bfc1af65 | 1735 | |
cf108bca | 1736 | unlock_page(page); |
f8514083 AK |
1737 | page_cache_release(page); |
1738 | if (pos + len > inode->i_size) | |
1739 | /* if we have allocated more blocks and copied | |
1740 | * less. We will have blocks allocated outside | |
1741 | * inode->i_size. So truncate them | |
1742 | */ | |
1743 | ext4_orphan_add(handle, inode); | |
1744 | ||
617ba13b | 1745 | ret2 = ext4_journal_stop(handle); |
ac27a0ec DK |
1746 | if (!ret) |
1747 | ret = ret2; | |
f8514083 AK |
1748 | if (pos + len > inode->i_size) { |
1749 | vmtruncate(inode, inode->i_size); | |
1750 | /* | |
1751 | * If vmtruncate failed early the inode might still be | |
1752 | * on the orphan list; we need to make sure the inode | |
1753 | * is removed from the orphan list in that case. | |
1754 | */ | |
1755 | if (inode->i_nlink) | |
1756 | ext4_orphan_del(NULL, inode); | |
1757 | } | |
bfc1af65 NP |
1758 | |
1759 | return ret ? ret : copied; | |
ac27a0ec | 1760 | } |
d2a17637 MC |
1761 | |
1762 | static int ext4_da_reserve_space(struct inode *inode, int nrblocks) | |
1763 | { | |
030ba6bc | 1764 | int retries = 0; |
60e58e0f MC |
1765 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
1766 | unsigned long md_needed, mdblocks, total = 0; | |
d2a17637 MC |
1767 | |
1768 | /* | |
1769 | * recalculate the amount of metadata blocks to reserve | |
1770 | * in order to allocate nrblocks | |
1771 | * worse case is one extent per block | |
1772 | */ | |
030ba6bc | 1773 | repeat: |
d2a17637 MC |
1774 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); |
1775 | total = EXT4_I(inode)->i_reserved_data_blocks + nrblocks; | |
1776 | mdblocks = ext4_calc_metadata_amount(inode, total); | |
1777 | BUG_ON(mdblocks < EXT4_I(inode)->i_reserved_meta_blocks); | |
1778 | ||
1779 | md_needed = mdblocks - EXT4_I(inode)->i_reserved_meta_blocks; | |
1780 | total = md_needed + nrblocks; | |
1781 | ||
60e58e0f MC |
1782 | /* |
1783 | * Make quota reservation here to prevent quota overflow | |
1784 | * later. Real quota accounting is done at pages writeout | |
1785 | * time. | |
1786 | */ | |
1787 | if (vfs_dq_reserve_block(inode, total)) { | |
1788 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
1789 | return -EDQUOT; | |
1790 | } | |
1791 | ||
a30d542a | 1792 | if (ext4_claim_free_blocks(sbi, total)) { |
d2a17637 | 1793 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
030ba6bc AK |
1794 | if (ext4_should_retry_alloc(inode->i_sb, &retries)) { |
1795 | yield(); | |
1796 | goto repeat; | |
1797 | } | |
60e58e0f | 1798 | vfs_dq_release_reservation_block(inode, total); |
d2a17637 MC |
1799 | return -ENOSPC; |
1800 | } | |
d2a17637 MC |
1801 | EXT4_I(inode)->i_reserved_data_blocks += nrblocks; |
1802 | EXT4_I(inode)->i_reserved_meta_blocks = mdblocks; | |
1803 | ||
1804 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
1805 | return 0; /* success */ | |
1806 | } | |
1807 | ||
12219aea | 1808 | static void ext4_da_release_space(struct inode *inode, int to_free) |
d2a17637 MC |
1809 | { |
1810 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
1811 | int total, mdb, mdb_free, release; | |
1812 | ||
cd213226 MC |
1813 | if (!to_free) |
1814 | return; /* Nothing to release, exit */ | |
1815 | ||
d2a17637 | 1816 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); |
cd213226 MC |
1817 | |
1818 | if (!EXT4_I(inode)->i_reserved_data_blocks) { | |
1819 | /* | |
1820 | * if there is no reserved blocks, but we try to free some | |
1821 | * then the counter is messed up somewhere. | |
1822 | * but since this function is called from invalidate | |
1823 | * page, it's harmless to return without any action | |
1824 | */ | |
1825 | printk(KERN_INFO "ext4 delalloc try to release %d reserved " | |
1826 | "blocks for inode %lu, but there is no reserved " | |
1827 | "data blocks\n", to_free, inode->i_ino); | |
1828 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
1829 | return; | |
1830 | } | |
1831 | ||
d2a17637 | 1832 | /* recalculate the number of metablocks still need to be reserved */ |
12219aea | 1833 | total = EXT4_I(inode)->i_reserved_data_blocks - to_free; |
d2a17637 MC |
1834 | mdb = ext4_calc_metadata_amount(inode, total); |
1835 | ||
1836 | /* figure out how many metablocks to release */ | |
1837 | BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks); | |
1838 | mdb_free = EXT4_I(inode)->i_reserved_meta_blocks - mdb; | |
1839 | ||
d2a17637 MC |
1840 | release = to_free + mdb_free; |
1841 | ||
6bc6e63f AK |
1842 | /* update fs dirty blocks counter for truncate case */ |
1843 | percpu_counter_sub(&sbi->s_dirtyblocks_counter, release); | |
d2a17637 MC |
1844 | |
1845 | /* update per-inode reservations */ | |
12219aea AK |
1846 | BUG_ON(to_free > EXT4_I(inode)->i_reserved_data_blocks); |
1847 | EXT4_I(inode)->i_reserved_data_blocks -= to_free; | |
d2a17637 MC |
1848 | |
1849 | BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks); | |
1850 | EXT4_I(inode)->i_reserved_meta_blocks = mdb; | |
d2a17637 | 1851 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); |
60e58e0f MC |
1852 | |
1853 | vfs_dq_release_reservation_block(inode, release); | |
d2a17637 MC |
1854 | } |
1855 | ||
1856 | static void ext4_da_page_release_reservation(struct page *page, | |
1857 | unsigned long offset) | |
1858 | { | |
1859 | int to_release = 0; | |
1860 | struct buffer_head *head, *bh; | |
1861 | unsigned int curr_off = 0; | |
1862 | ||
1863 | head = page_buffers(page); | |
1864 | bh = head; | |
1865 | do { | |
1866 | unsigned int next_off = curr_off + bh->b_size; | |
1867 | ||
1868 | if ((offset <= curr_off) && (buffer_delay(bh))) { | |
1869 | to_release++; | |
1870 | clear_buffer_delay(bh); | |
1871 | } | |
1872 | curr_off = next_off; | |
1873 | } while ((bh = bh->b_this_page) != head); | |
12219aea | 1874 | ext4_da_release_space(page->mapping->host, to_release); |
d2a17637 | 1875 | } |
ac27a0ec | 1876 | |
64769240 AT |
1877 | /* |
1878 | * Delayed allocation stuff | |
1879 | */ | |
1880 | ||
1881 | struct mpage_da_data { | |
1882 | struct inode *inode; | |
8dc207c0 TT |
1883 | sector_t b_blocknr; /* start block number of extent */ |
1884 | size_t b_size; /* size of extent */ | |
1885 | unsigned long b_state; /* state of the extent */ | |
64769240 | 1886 | unsigned long first_page, next_page; /* extent of pages */ |
64769240 | 1887 | struct writeback_control *wbc; |
a1d6cc56 | 1888 | int io_done; |
498e5f24 | 1889 | int pages_written; |
df22291f | 1890 | int retval; |
64769240 AT |
1891 | }; |
1892 | ||
1893 | /* | |
1894 | * mpage_da_submit_io - walks through extent of pages and try to write | |
a1d6cc56 | 1895 | * them with writepage() call back |
64769240 AT |
1896 | * |
1897 | * @mpd->inode: inode | |
1898 | * @mpd->first_page: first page of the extent | |
1899 | * @mpd->next_page: page after the last page of the extent | |
64769240 AT |
1900 | * |
1901 | * By the time mpage_da_submit_io() is called we expect all blocks | |
1902 | * to be allocated. this may be wrong if allocation failed. | |
1903 | * | |
1904 | * As pages are already locked by write_cache_pages(), we can't use it | |
1905 | */ | |
1906 | static int mpage_da_submit_io(struct mpage_da_data *mpd) | |
1907 | { | |
22208ded | 1908 | long pages_skipped; |
791b7f08 AK |
1909 | struct pagevec pvec; |
1910 | unsigned long index, end; | |
1911 | int ret = 0, err, nr_pages, i; | |
1912 | struct inode *inode = mpd->inode; | |
1913 | struct address_space *mapping = inode->i_mapping; | |
64769240 AT |
1914 | |
1915 | BUG_ON(mpd->next_page <= mpd->first_page); | |
791b7f08 AK |
1916 | /* |
1917 | * We need to start from the first_page to the next_page - 1 | |
1918 | * to make sure we also write the mapped dirty buffer_heads. | |
8dc207c0 | 1919 | * If we look at mpd->b_blocknr we would only be looking |
791b7f08 AK |
1920 | * at the currently mapped buffer_heads. |
1921 | */ | |
64769240 AT |
1922 | index = mpd->first_page; |
1923 | end = mpd->next_page - 1; | |
1924 | ||
791b7f08 | 1925 | pagevec_init(&pvec, 0); |
64769240 | 1926 | while (index <= end) { |
791b7f08 | 1927 | nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE); |
64769240 AT |
1928 | if (nr_pages == 0) |
1929 | break; | |
1930 | for (i = 0; i < nr_pages; i++) { | |
1931 | struct page *page = pvec.pages[i]; | |
1932 | ||
791b7f08 AK |
1933 | index = page->index; |
1934 | if (index > end) | |
1935 | break; | |
1936 | index++; | |
1937 | ||
1938 | BUG_ON(!PageLocked(page)); | |
1939 | BUG_ON(PageWriteback(page)); | |
1940 | ||
22208ded | 1941 | pages_skipped = mpd->wbc->pages_skipped; |
a1d6cc56 | 1942 | err = mapping->a_ops->writepage(page, mpd->wbc); |
22208ded AK |
1943 | if (!err && (pages_skipped == mpd->wbc->pages_skipped)) |
1944 | /* | |
1945 | * have successfully written the page | |
1946 | * without skipping the same | |
1947 | */ | |
a1d6cc56 | 1948 | mpd->pages_written++; |
64769240 AT |
1949 | /* |
1950 | * In error case, we have to continue because | |
1951 | * remaining pages are still locked | |
1952 | * XXX: unlock and re-dirty them? | |
1953 | */ | |
1954 | if (ret == 0) | |
1955 | ret = err; | |
1956 | } | |
1957 | pagevec_release(&pvec); | |
1958 | } | |
64769240 AT |
1959 | return ret; |
1960 | } | |
1961 | ||
1962 | /* | |
1963 | * mpage_put_bnr_to_bhs - walk blocks and assign them actual numbers | |
1964 | * | |
1965 | * @mpd->inode - inode to walk through | |
1966 | * @exbh->b_blocknr - first block on a disk | |
1967 | * @exbh->b_size - amount of space in bytes | |
1968 | * @logical - first logical block to start assignment with | |
1969 | * | |
1970 | * the function goes through all passed space and put actual disk | |
29fa89d0 | 1971 | * block numbers into buffer heads, dropping BH_Delay and BH_Unwritten |
64769240 AT |
1972 | */ |
1973 | static void mpage_put_bnr_to_bhs(struct mpage_da_data *mpd, sector_t logical, | |
1974 | struct buffer_head *exbh) | |
1975 | { | |
1976 | struct inode *inode = mpd->inode; | |
1977 | struct address_space *mapping = inode->i_mapping; | |
1978 | int blocks = exbh->b_size >> inode->i_blkbits; | |
1979 | sector_t pblock = exbh->b_blocknr, cur_logical; | |
1980 | struct buffer_head *head, *bh; | |
a1d6cc56 | 1981 | pgoff_t index, end; |
64769240 AT |
1982 | struct pagevec pvec; |
1983 | int nr_pages, i; | |
1984 | ||
1985 | index = logical >> (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
1986 | end = (logical + blocks - 1) >> (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
1987 | cur_logical = index << (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
1988 | ||
1989 | pagevec_init(&pvec, 0); | |
1990 | ||
1991 | while (index <= end) { | |
1992 | /* XXX: optimize tail */ | |
1993 | nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE); | |
1994 | if (nr_pages == 0) | |
1995 | break; | |
1996 | for (i = 0; i < nr_pages; i++) { | |
1997 | struct page *page = pvec.pages[i]; | |
1998 | ||
1999 | index = page->index; | |
2000 | if (index > end) | |
2001 | break; | |
2002 | index++; | |
2003 | ||
2004 | BUG_ON(!PageLocked(page)); | |
2005 | BUG_ON(PageWriteback(page)); | |
2006 | BUG_ON(!page_has_buffers(page)); | |
2007 | ||
2008 | bh = page_buffers(page); | |
2009 | head = bh; | |
2010 | ||
2011 | /* skip blocks out of the range */ | |
2012 | do { | |
2013 | if (cur_logical >= logical) | |
2014 | break; | |
2015 | cur_logical++; | |
2016 | } while ((bh = bh->b_this_page) != head); | |
2017 | ||
2018 | do { | |
2019 | if (cur_logical >= logical + blocks) | |
2020 | break; | |
29fa89d0 AK |
2021 | |
2022 | if (buffer_delay(bh) || | |
2023 | buffer_unwritten(bh)) { | |
2024 | ||
2025 | BUG_ON(bh->b_bdev != inode->i_sb->s_bdev); | |
2026 | ||
2027 | if (buffer_delay(bh)) { | |
2028 | clear_buffer_delay(bh); | |
2029 | bh->b_blocknr = pblock; | |
2030 | } else { | |
2031 | /* | |
2032 | * unwritten already should have | |
2033 | * blocknr assigned. Verify that | |
2034 | */ | |
2035 | clear_buffer_unwritten(bh); | |
2036 | BUG_ON(bh->b_blocknr != pblock); | |
2037 | } | |
2038 | ||
61628a3f | 2039 | } else if (buffer_mapped(bh)) |
64769240 | 2040 | BUG_ON(bh->b_blocknr != pblock); |
64769240 AT |
2041 | |
2042 | cur_logical++; | |
2043 | pblock++; | |
2044 | } while ((bh = bh->b_this_page) != head); | |
2045 | } | |
2046 | pagevec_release(&pvec); | |
2047 | } | |
2048 | } | |
2049 | ||
2050 | ||
2051 | /* | |
2052 | * __unmap_underlying_blocks - just a helper function to unmap | |
2053 | * set of blocks described by @bh | |
2054 | */ | |
2055 | static inline void __unmap_underlying_blocks(struct inode *inode, | |
2056 | struct buffer_head *bh) | |
2057 | { | |
2058 | struct block_device *bdev = inode->i_sb->s_bdev; | |
2059 | int blocks, i; | |
2060 | ||
2061 | blocks = bh->b_size >> inode->i_blkbits; | |
2062 | for (i = 0; i < blocks; i++) | |
2063 | unmap_underlying_metadata(bdev, bh->b_blocknr + i); | |
2064 | } | |
2065 | ||
c4a0c46e AK |
2066 | static void ext4_da_block_invalidatepages(struct mpage_da_data *mpd, |
2067 | sector_t logical, long blk_cnt) | |
2068 | { | |
2069 | int nr_pages, i; | |
2070 | pgoff_t index, end; | |
2071 | struct pagevec pvec; | |
2072 | struct inode *inode = mpd->inode; | |
2073 | struct address_space *mapping = inode->i_mapping; | |
2074 | ||
2075 | index = logical >> (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2076 | end = (logical + blk_cnt - 1) >> | |
2077 | (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2078 | while (index <= end) { | |
2079 | nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE); | |
2080 | if (nr_pages == 0) | |
2081 | break; | |
2082 | for (i = 0; i < nr_pages; i++) { | |
2083 | struct page *page = pvec.pages[i]; | |
2084 | index = page->index; | |
2085 | if (index > end) | |
2086 | break; | |
2087 | index++; | |
2088 | ||
2089 | BUG_ON(!PageLocked(page)); | |
2090 | BUG_ON(PageWriteback(page)); | |
2091 | block_invalidatepage(page, 0); | |
2092 | ClearPageUptodate(page); | |
2093 | unlock_page(page); | |
2094 | } | |
2095 | } | |
2096 | return; | |
2097 | } | |
2098 | ||
df22291f AK |
2099 | static void ext4_print_free_blocks(struct inode *inode) |
2100 | { | |
2101 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
2102 | printk(KERN_EMERG "Total free blocks count %lld\n", | |
2103 | ext4_count_free_blocks(inode->i_sb)); | |
2104 | printk(KERN_EMERG "Free/Dirty block details\n"); | |
2105 | printk(KERN_EMERG "free_blocks=%lld\n", | |
8f72fbdf | 2106 | (long long)percpu_counter_sum(&sbi->s_freeblocks_counter)); |
df22291f | 2107 | printk(KERN_EMERG "dirty_blocks=%lld\n", |
8f72fbdf | 2108 | (long long)percpu_counter_sum(&sbi->s_dirtyblocks_counter)); |
df22291f | 2109 | printk(KERN_EMERG "Block reservation details\n"); |
498e5f24 | 2110 | printk(KERN_EMERG "i_reserved_data_blocks=%u\n", |
df22291f | 2111 | EXT4_I(inode)->i_reserved_data_blocks); |
498e5f24 | 2112 | printk(KERN_EMERG "i_reserved_meta_blocks=%u\n", |
df22291f AK |
2113 | EXT4_I(inode)->i_reserved_meta_blocks); |
2114 | return; | |
2115 | } | |
2116 | ||
64769240 AT |
2117 | /* |
2118 | * mpage_da_map_blocks - go through given space | |
2119 | * | |
8dc207c0 | 2120 | * @mpd - bh describing space |
64769240 AT |
2121 | * |
2122 | * The function skips space we know is already mapped to disk blocks. | |
2123 | * | |
64769240 | 2124 | */ |
ed5bde0b | 2125 | static int mpage_da_map_blocks(struct mpage_da_data *mpd) |
64769240 | 2126 | { |
2ac3b6e0 | 2127 | int err, blks, get_blocks_flags; |
030ba6bc | 2128 | struct buffer_head new; |
2fa3cdfb TT |
2129 | sector_t next = mpd->b_blocknr; |
2130 | unsigned max_blocks = mpd->b_size >> mpd->inode->i_blkbits; | |
2131 | loff_t disksize = EXT4_I(mpd->inode)->i_disksize; | |
2132 | handle_t *handle = NULL; | |
64769240 AT |
2133 | |
2134 | /* | |
2135 | * We consider only non-mapped and non-allocated blocks | |
2136 | */ | |
8dc207c0 | 2137 | if ((mpd->b_state & (1 << BH_Mapped)) && |
29fa89d0 AK |
2138 | !(mpd->b_state & (1 << BH_Delay)) && |
2139 | !(mpd->b_state & (1 << BH_Unwritten))) | |
c4a0c46e | 2140 | return 0; |
2fa3cdfb TT |
2141 | |
2142 | /* | |
2143 | * If we didn't accumulate anything to write simply return | |
2144 | */ | |
2145 | if (!mpd->b_size) | |
2146 | return 0; | |
2147 | ||
2148 | handle = ext4_journal_current_handle(); | |
2149 | BUG_ON(!handle); | |
2150 | ||
79ffab34 | 2151 | /* |
2ac3b6e0 TT |
2152 | * Call ext4_get_blocks() to allocate any delayed allocation |
2153 | * blocks, or to convert an uninitialized extent to be | |
2154 | * initialized (in the case where we have written into | |
2155 | * one or more preallocated blocks). | |
2156 | * | |
2157 | * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE to | |
2158 | * indicate that we are on the delayed allocation path. This | |
2159 | * affects functions in many different parts of the allocation | |
2160 | * call path. This flag exists primarily because we don't | |
2161 | * want to change *many* call functions, so ext4_get_blocks() | |
2162 | * will set the magic i_delalloc_reserved_flag once the | |
2163 | * inode's allocation semaphore is taken. | |
2164 | * | |
2165 | * If the blocks in questions were delalloc blocks, set | |
2166 | * EXT4_GET_BLOCKS_DELALLOC_RESERVE so the delalloc accounting | |
2167 | * variables are updated after the blocks have been allocated. | |
79ffab34 | 2168 | */ |
2ac3b6e0 TT |
2169 | new.b_state = 0; |
2170 | get_blocks_flags = (EXT4_GET_BLOCKS_CREATE | | |
2171 | EXT4_GET_BLOCKS_DELALLOC_RESERVE); | |
2172 | if (mpd->b_state & (1 << BH_Delay)) | |
2173 | get_blocks_flags |= EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE; | |
2fa3cdfb | 2174 | blks = ext4_get_blocks(handle, mpd->inode, next, max_blocks, |
2ac3b6e0 | 2175 | &new, get_blocks_flags); |
2fa3cdfb TT |
2176 | if (blks < 0) { |
2177 | err = blks; | |
ed5bde0b TT |
2178 | /* |
2179 | * If get block returns with error we simply | |
2180 | * return. Later writepage will redirty the page and | |
2181 | * writepages will find the dirty page again | |
c4a0c46e AK |
2182 | */ |
2183 | if (err == -EAGAIN) | |
2184 | return 0; | |
df22291f AK |
2185 | |
2186 | if (err == -ENOSPC && | |
ed5bde0b | 2187 | ext4_count_free_blocks(mpd->inode->i_sb)) { |
df22291f AK |
2188 | mpd->retval = err; |
2189 | return 0; | |
2190 | } | |
2191 | ||
c4a0c46e | 2192 | /* |
ed5bde0b TT |
2193 | * get block failure will cause us to loop in |
2194 | * writepages, because a_ops->writepage won't be able | |
2195 | * to make progress. The page will be redirtied by | |
2196 | * writepage and writepages will again try to write | |
2197 | * the same. | |
c4a0c46e AK |
2198 | */ |
2199 | printk(KERN_EMERG "%s block allocation failed for inode %lu " | |
2200 | "at logical offset %llu with max blocks " | |
2201 | "%zd with error %d\n", | |
2202 | __func__, mpd->inode->i_ino, | |
2203 | (unsigned long long)next, | |
8dc207c0 | 2204 | mpd->b_size >> mpd->inode->i_blkbits, err); |
c4a0c46e AK |
2205 | printk(KERN_EMERG "This should not happen.!! " |
2206 | "Data will be lost\n"); | |
030ba6bc | 2207 | if (err == -ENOSPC) { |
df22291f | 2208 | ext4_print_free_blocks(mpd->inode); |
030ba6bc | 2209 | } |
2fa3cdfb | 2210 | /* invalidate all the pages */ |
c4a0c46e | 2211 | ext4_da_block_invalidatepages(mpd, next, |
8dc207c0 | 2212 | mpd->b_size >> mpd->inode->i_blkbits); |
c4a0c46e AK |
2213 | return err; |
2214 | } | |
2fa3cdfb TT |
2215 | BUG_ON(blks == 0); |
2216 | ||
2217 | new.b_size = (blks << mpd->inode->i_blkbits); | |
64769240 | 2218 | |
a1d6cc56 AK |
2219 | if (buffer_new(&new)) |
2220 | __unmap_underlying_blocks(mpd->inode, &new); | |
64769240 | 2221 | |
a1d6cc56 AK |
2222 | /* |
2223 | * If blocks are delayed marked, we need to | |
2224 | * put actual blocknr and drop delayed bit | |
2225 | */ | |
8dc207c0 TT |
2226 | if ((mpd->b_state & (1 << BH_Delay)) || |
2227 | (mpd->b_state & (1 << BH_Unwritten))) | |
a1d6cc56 | 2228 | mpage_put_bnr_to_bhs(mpd, next, &new); |
64769240 | 2229 | |
2fa3cdfb TT |
2230 | if (ext4_should_order_data(mpd->inode)) { |
2231 | err = ext4_jbd2_file_inode(handle, mpd->inode); | |
2232 | if (err) | |
2233 | return err; | |
2234 | } | |
2235 | ||
2236 | /* | |
03f5d8bc | 2237 | * Update on-disk size along with block allocation. |
2fa3cdfb TT |
2238 | */ |
2239 | disksize = ((loff_t) next + blks) << mpd->inode->i_blkbits; | |
2240 | if (disksize > i_size_read(mpd->inode)) | |
2241 | disksize = i_size_read(mpd->inode); | |
2242 | if (disksize > EXT4_I(mpd->inode)->i_disksize) { | |
2243 | ext4_update_i_disksize(mpd->inode, disksize); | |
2244 | return ext4_mark_inode_dirty(handle, mpd->inode); | |
2245 | } | |
2246 | ||
c4a0c46e | 2247 | return 0; |
64769240 AT |
2248 | } |
2249 | ||
bf068ee2 AK |
2250 | #define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | \ |
2251 | (1 << BH_Delay) | (1 << BH_Unwritten)) | |
64769240 AT |
2252 | |
2253 | /* | |
2254 | * mpage_add_bh_to_extent - try to add one more block to extent of blocks | |
2255 | * | |
2256 | * @mpd->lbh - extent of blocks | |
2257 | * @logical - logical number of the block in the file | |
2258 | * @bh - bh of the block (used to access block's state) | |
2259 | * | |
2260 | * the function is used to collect contig. blocks in same state | |
2261 | */ | |
2262 | static void mpage_add_bh_to_extent(struct mpage_da_data *mpd, | |
8dc207c0 TT |
2263 | sector_t logical, size_t b_size, |
2264 | unsigned long b_state) | |
64769240 | 2265 | { |
64769240 | 2266 | sector_t next; |
8dc207c0 | 2267 | int nrblocks = mpd->b_size >> mpd->inode->i_blkbits; |
64769240 | 2268 | |
525f4ed8 MC |
2269 | /* check if thereserved journal credits might overflow */ |
2270 | if (!(EXT4_I(mpd->inode)->i_flags & EXT4_EXTENTS_FL)) { | |
2271 | if (nrblocks >= EXT4_MAX_TRANS_DATA) { | |
2272 | /* | |
2273 | * With non-extent format we are limited by the journal | |
2274 | * credit available. Total credit needed to insert | |
2275 | * nrblocks contiguous blocks is dependent on the | |
2276 | * nrblocks. So limit nrblocks. | |
2277 | */ | |
2278 | goto flush_it; | |
2279 | } else if ((nrblocks + (b_size >> mpd->inode->i_blkbits)) > | |
2280 | EXT4_MAX_TRANS_DATA) { | |
2281 | /* | |
2282 | * Adding the new buffer_head would make it cross the | |
2283 | * allowed limit for which we have journal credit | |
2284 | * reserved. So limit the new bh->b_size | |
2285 | */ | |
2286 | b_size = (EXT4_MAX_TRANS_DATA - nrblocks) << | |
2287 | mpd->inode->i_blkbits; | |
2288 | /* we will do mpage_da_submit_io in the next loop */ | |
2289 | } | |
2290 | } | |
64769240 AT |
2291 | /* |
2292 | * First block in the extent | |
2293 | */ | |
8dc207c0 TT |
2294 | if (mpd->b_size == 0) { |
2295 | mpd->b_blocknr = logical; | |
2296 | mpd->b_size = b_size; | |
2297 | mpd->b_state = b_state & BH_FLAGS; | |
64769240 AT |
2298 | return; |
2299 | } | |
2300 | ||
8dc207c0 | 2301 | next = mpd->b_blocknr + nrblocks; |
64769240 AT |
2302 | /* |
2303 | * Can we merge the block to our big extent? | |
2304 | */ | |
8dc207c0 TT |
2305 | if (logical == next && (b_state & BH_FLAGS) == mpd->b_state) { |
2306 | mpd->b_size += b_size; | |
64769240 AT |
2307 | return; |
2308 | } | |
2309 | ||
525f4ed8 | 2310 | flush_it: |
64769240 AT |
2311 | /* |
2312 | * We couldn't merge the block to our extent, so we | |
2313 | * need to flush current extent and start new one | |
2314 | */ | |
c4a0c46e AK |
2315 | if (mpage_da_map_blocks(mpd) == 0) |
2316 | mpage_da_submit_io(mpd); | |
a1d6cc56 AK |
2317 | mpd->io_done = 1; |
2318 | return; | |
64769240 AT |
2319 | } |
2320 | ||
29fa89d0 AK |
2321 | static int ext4_bh_unmapped_or_delay(handle_t *handle, struct buffer_head *bh) |
2322 | { | |
2323 | /* | |
2324 | * unmapped buffer is possible for holes. | |
2325 | * delay buffer is possible with delayed allocation. | |
2326 | * We also need to consider unwritten buffer as unmapped. | |
2327 | */ | |
2328 | return (!buffer_mapped(bh) || buffer_delay(bh) || | |
2329 | buffer_unwritten(bh)) && buffer_dirty(bh); | |
2330 | } | |
2331 | ||
64769240 AT |
2332 | /* |
2333 | * __mpage_da_writepage - finds extent of pages and blocks | |
2334 | * | |
2335 | * @page: page to consider | |
2336 | * @wbc: not used, we just follow rules | |
2337 | * @data: context | |
2338 | * | |
2339 | * The function finds extents of pages and scan them for all blocks. | |
2340 | */ | |
2341 | static int __mpage_da_writepage(struct page *page, | |
2342 | struct writeback_control *wbc, void *data) | |
2343 | { | |
2344 | struct mpage_da_data *mpd = data; | |
2345 | struct inode *inode = mpd->inode; | |
8dc207c0 | 2346 | struct buffer_head *bh, *head; |
64769240 AT |
2347 | sector_t logical; |
2348 | ||
a1d6cc56 AK |
2349 | if (mpd->io_done) { |
2350 | /* | |
2351 | * Rest of the page in the page_vec | |
2352 | * redirty then and skip then. We will | |
2353 | * try to to write them again after | |
2354 | * starting a new transaction | |
2355 | */ | |
2356 | redirty_page_for_writepage(wbc, page); | |
2357 | unlock_page(page); | |
2358 | return MPAGE_DA_EXTENT_TAIL; | |
2359 | } | |
64769240 AT |
2360 | /* |
2361 | * Can we merge this page to current extent? | |
2362 | */ | |
2363 | if (mpd->next_page != page->index) { | |
2364 | /* | |
2365 | * Nope, we can't. So, we map non-allocated blocks | |
a1d6cc56 | 2366 | * and start IO on them using writepage() |
64769240 AT |
2367 | */ |
2368 | if (mpd->next_page != mpd->first_page) { | |
c4a0c46e AK |
2369 | if (mpage_da_map_blocks(mpd) == 0) |
2370 | mpage_da_submit_io(mpd); | |
a1d6cc56 AK |
2371 | /* |
2372 | * skip rest of the page in the page_vec | |
2373 | */ | |
2374 | mpd->io_done = 1; | |
2375 | redirty_page_for_writepage(wbc, page); | |
2376 | unlock_page(page); | |
2377 | return MPAGE_DA_EXTENT_TAIL; | |
64769240 AT |
2378 | } |
2379 | ||
2380 | /* | |
2381 | * Start next extent of pages ... | |
2382 | */ | |
2383 | mpd->first_page = page->index; | |
2384 | ||
2385 | /* | |
2386 | * ... and blocks | |
2387 | */ | |
8dc207c0 TT |
2388 | mpd->b_size = 0; |
2389 | mpd->b_state = 0; | |
2390 | mpd->b_blocknr = 0; | |
64769240 AT |
2391 | } |
2392 | ||
2393 | mpd->next_page = page->index + 1; | |
2394 | logical = (sector_t) page->index << | |
2395 | (PAGE_CACHE_SHIFT - inode->i_blkbits); | |
2396 | ||
2397 | if (!page_has_buffers(page)) { | |
8dc207c0 TT |
2398 | mpage_add_bh_to_extent(mpd, logical, PAGE_CACHE_SIZE, |
2399 | (1 << BH_Dirty) | (1 << BH_Uptodate)); | |
a1d6cc56 AK |
2400 | if (mpd->io_done) |
2401 | return MPAGE_DA_EXTENT_TAIL; | |
64769240 AT |
2402 | } else { |
2403 | /* | |
2404 | * Page with regular buffer heads, just add all dirty ones | |
2405 | */ | |
2406 | head = page_buffers(page); | |
2407 | bh = head; | |
2408 | do { | |
2409 | BUG_ON(buffer_locked(bh)); | |
791b7f08 AK |
2410 | /* |
2411 | * We need to try to allocate | |
2412 | * unmapped blocks in the same page. | |
2413 | * Otherwise we won't make progress | |
2414 | * with the page in ext4_da_writepage | |
2415 | */ | |
29fa89d0 | 2416 | if (ext4_bh_unmapped_or_delay(NULL, bh)) { |
8dc207c0 TT |
2417 | mpage_add_bh_to_extent(mpd, logical, |
2418 | bh->b_size, | |
2419 | bh->b_state); | |
a1d6cc56 AK |
2420 | if (mpd->io_done) |
2421 | return MPAGE_DA_EXTENT_TAIL; | |
791b7f08 AK |
2422 | } else if (buffer_dirty(bh) && (buffer_mapped(bh))) { |
2423 | /* | |
2424 | * mapped dirty buffer. We need to update | |
2425 | * the b_state because we look at | |
2426 | * b_state in mpage_da_map_blocks. We don't | |
2427 | * update b_size because if we find an | |
2428 | * unmapped buffer_head later we need to | |
2429 | * use the b_state flag of that buffer_head. | |
2430 | */ | |
8dc207c0 TT |
2431 | if (mpd->b_size == 0) |
2432 | mpd->b_state = bh->b_state & BH_FLAGS; | |
a1d6cc56 | 2433 | } |
64769240 AT |
2434 | logical++; |
2435 | } while ((bh = bh->b_this_page) != head); | |
2436 | } | |
2437 | ||
2438 | return 0; | |
2439 | } | |
2440 | ||
64769240 | 2441 | /* |
b920c755 TT |
2442 | * This is a special get_blocks_t callback which is used by |
2443 | * ext4_da_write_begin(). It will either return mapped block or | |
2444 | * reserve space for a single block. | |
29fa89d0 AK |
2445 | * |
2446 | * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set. | |
2447 | * We also have b_blocknr = -1 and b_bdev initialized properly | |
2448 | * | |
2449 | * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set. | |
2450 | * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev | |
2451 | * initialized properly. | |
64769240 AT |
2452 | */ |
2453 | static int ext4_da_get_block_prep(struct inode *inode, sector_t iblock, | |
2454 | struct buffer_head *bh_result, int create) | |
2455 | { | |
2456 | int ret = 0; | |
33b9817e AK |
2457 | sector_t invalid_block = ~((sector_t) 0xffff); |
2458 | ||
2459 | if (invalid_block < ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es)) | |
2460 | invalid_block = ~0; | |
64769240 AT |
2461 | |
2462 | BUG_ON(create == 0); | |
2463 | BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize); | |
2464 | ||
2465 | /* | |
2466 | * first, we need to know whether the block is allocated already | |
2467 | * preallocated blocks are unmapped but should treated | |
2468 | * the same as allocated blocks. | |
2469 | */ | |
c2177057 | 2470 | ret = ext4_get_blocks(NULL, inode, iblock, 1, bh_result, 0); |
d2a17637 MC |
2471 | if ((ret == 0) && !buffer_delay(bh_result)) { |
2472 | /* the block isn't (pre)allocated yet, let's reserve space */ | |
64769240 AT |
2473 | /* |
2474 | * XXX: __block_prepare_write() unmaps passed block, | |
2475 | * is it OK? | |
2476 | */ | |
d2a17637 MC |
2477 | ret = ext4_da_reserve_space(inode, 1); |
2478 | if (ret) | |
2479 | /* not enough space to reserve */ | |
2480 | return ret; | |
2481 | ||
33b9817e | 2482 | map_bh(bh_result, inode->i_sb, invalid_block); |
64769240 AT |
2483 | set_buffer_new(bh_result); |
2484 | set_buffer_delay(bh_result); | |
2485 | } else if (ret > 0) { | |
2486 | bh_result->b_size = (ret << inode->i_blkbits); | |
29fa89d0 AK |
2487 | if (buffer_unwritten(bh_result)) { |
2488 | /* A delayed write to unwritten bh should | |
2489 | * be marked new and mapped. Mapped ensures | |
2490 | * that we don't do get_block multiple times | |
2491 | * when we write to the same offset and new | |
2492 | * ensures that we do proper zero out for | |
2493 | * partial write. | |
2494 | */ | |
9c1ee184 | 2495 | set_buffer_new(bh_result); |
29fa89d0 AK |
2496 | set_buffer_mapped(bh_result); |
2497 | } | |
64769240 AT |
2498 | ret = 0; |
2499 | } | |
2500 | ||
2501 | return ret; | |
2502 | } | |
61628a3f | 2503 | |
b920c755 TT |
2504 | /* |
2505 | * This function is used as a standard get_block_t calback function | |
2506 | * when there is no desire to allocate any blocks. It is used as a | |
2507 | * callback function for block_prepare_write(), nobh_writepage(), and | |
2508 | * block_write_full_page(). These functions should only try to map a | |
2509 | * single block at a time. | |
2510 | * | |
2511 | * Since this function doesn't do block allocations even if the caller | |
2512 | * requests it by passing in create=1, it is critically important that | |
2513 | * any caller checks to make sure that any buffer heads are returned | |
2514 | * by this function are either all already mapped or marked for | |
2515 | * delayed allocation before calling nobh_writepage() or | |
2516 | * block_write_full_page(). Otherwise, b_blocknr could be left | |
2517 | * unitialized, and the page write functions will be taken by | |
2518 | * surprise. | |
2519 | */ | |
2520 | static int noalloc_get_block_write(struct inode *inode, sector_t iblock, | |
f0e6c985 AK |
2521 | struct buffer_head *bh_result, int create) |
2522 | { | |
2523 | int ret = 0; | |
2524 | unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; | |
2525 | ||
a2dc52b5 TT |
2526 | BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize); |
2527 | ||
f0e6c985 AK |
2528 | /* |
2529 | * we don't want to do block allocation in writepage | |
2530 | * so call get_block_wrap with create = 0 | |
2531 | */ | |
c2177057 | 2532 | ret = ext4_get_blocks(NULL, inode, iblock, max_blocks, bh_result, 0); |
a2dc52b5 | 2533 | BUG_ON(create && ret == 0); |
f0e6c985 AK |
2534 | if (ret > 0) { |
2535 | bh_result->b_size = (ret << inode->i_blkbits); | |
2536 | ret = 0; | |
2537 | } | |
2538 | return ret; | |
61628a3f MC |
2539 | } |
2540 | ||
61628a3f | 2541 | /* |
b920c755 TT |
2542 | * This function can get called via... |
2543 | * - ext4_da_writepages after taking page lock (have journal handle) | |
2544 | * - journal_submit_inode_data_buffers (no journal handle) | |
2545 | * - shrink_page_list via pdflush (no journal handle) | |
2546 | * - grab_page_cache when doing write_begin (have journal handle) | |
61628a3f | 2547 | */ |
64769240 AT |
2548 | static int ext4_da_writepage(struct page *page, |
2549 | struct writeback_control *wbc) | |
2550 | { | |
64769240 | 2551 | int ret = 0; |
61628a3f | 2552 | loff_t size; |
498e5f24 | 2553 | unsigned int len; |
61628a3f MC |
2554 | struct buffer_head *page_bufs; |
2555 | struct inode *inode = page->mapping->host; | |
2556 | ||
ba80b101 TT |
2557 | trace_mark(ext4_da_writepage, |
2558 | "dev %s ino %lu page_index %lu", | |
2559 | inode->i_sb->s_id, inode->i_ino, page->index); | |
f0e6c985 AK |
2560 | size = i_size_read(inode); |
2561 | if (page->index == size >> PAGE_CACHE_SHIFT) | |
2562 | len = size & ~PAGE_CACHE_MASK; | |
2563 | else | |
2564 | len = PAGE_CACHE_SIZE; | |
64769240 | 2565 | |
f0e6c985 | 2566 | if (page_has_buffers(page)) { |
61628a3f | 2567 | page_bufs = page_buffers(page); |
f0e6c985 AK |
2568 | if (walk_page_buffers(NULL, page_bufs, 0, len, NULL, |
2569 | ext4_bh_unmapped_or_delay)) { | |
61628a3f | 2570 | /* |
f0e6c985 AK |
2571 | * We don't want to do block allocation |
2572 | * So redirty the page and return | |
cd1aac32 AK |
2573 | * We may reach here when we do a journal commit |
2574 | * via journal_submit_inode_data_buffers. | |
2575 | * If we don't have mapping block we just ignore | |
f0e6c985 AK |
2576 | * them. We can also reach here via shrink_page_list |
2577 | */ | |
2578 | redirty_page_for_writepage(wbc, page); | |
2579 | unlock_page(page); | |
2580 | return 0; | |
2581 | } | |
2582 | } else { | |
2583 | /* | |
2584 | * The test for page_has_buffers() is subtle: | |
2585 | * We know the page is dirty but it lost buffers. That means | |
2586 | * that at some moment in time after write_begin()/write_end() | |
2587 | * has been called all buffers have been clean and thus they | |
2588 | * must have been written at least once. So they are all | |
2589 | * mapped and we can happily proceed with mapping them | |
2590 | * and writing the page. | |
2591 | * | |
2592 | * Try to initialize the buffer_heads and check whether | |
2593 | * all are mapped and non delay. We don't want to | |
2594 | * do block allocation here. | |
2595 | */ | |
2596 | ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE, | |
b920c755 | 2597 | noalloc_get_block_write); |
f0e6c985 AK |
2598 | if (!ret) { |
2599 | page_bufs = page_buffers(page); | |
2600 | /* check whether all are mapped and non delay */ | |
2601 | if (walk_page_buffers(NULL, page_bufs, 0, len, NULL, | |
2602 | ext4_bh_unmapped_or_delay)) { | |
2603 | redirty_page_for_writepage(wbc, page); | |
2604 | unlock_page(page); | |
2605 | return 0; | |
2606 | } | |
2607 | } else { | |
2608 | /* | |
2609 | * We can't do block allocation here | |
2610 | * so just redity the page and unlock | |
2611 | * and return | |
61628a3f | 2612 | */ |
61628a3f MC |
2613 | redirty_page_for_writepage(wbc, page); |
2614 | unlock_page(page); | |
2615 | return 0; | |
2616 | } | |
ed9b3e33 AK |
2617 | /* now mark the buffer_heads as dirty and uptodate */ |
2618 | block_commit_write(page, 0, PAGE_CACHE_SIZE); | |
64769240 AT |
2619 | } |
2620 | ||
2621 | if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode)) | |
b920c755 | 2622 | ret = nobh_writepage(page, noalloc_get_block_write, wbc); |
64769240 | 2623 | else |
b920c755 TT |
2624 | ret = block_write_full_page(page, noalloc_get_block_write, |
2625 | wbc); | |
64769240 | 2626 | |
64769240 AT |
2627 | return ret; |
2628 | } | |
2629 | ||
61628a3f | 2630 | /* |
525f4ed8 MC |
2631 | * This is called via ext4_da_writepages() to |
2632 | * calulate the total number of credits to reserve to fit | |
2633 | * a single extent allocation into a single transaction, | |
2634 | * ext4_da_writpeages() will loop calling this before | |
2635 | * the block allocation. | |
61628a3f | 2636 | */ |
525f4ed8 MC |
2637 | |
2638 | static int ext4_da_writepages_trans_blocks(struct inode *inode) | |
2639 | { | |
2640 | int max_blocks = EXT4_I(inode)->i_reserved_data_blocks; | |
2641 | ||
2642 | /* | |
2643 | * With non-extent format the journal credit needed to | |
2644 | * insert nrblocks contiguous block is dependent on | |
2645 | * number of contiguous block. So we will limit | |
2646 | * number of contiguous block to a sane value | |
2647 | */ | |
2648 | if (!(inode->i_flags & EXT4_EXTENTS_FL) && | |
2649 | (max_blocks > EXT4_MAX_TRANS_DATA)) | |
2650 | max_blocks = EXT4_MAX_TRANS_DATA; | |
2651 | ||
2652 | return ext4_chunk_trans_blocks(inode, max_blocks); | |
2653 | } | |
61628a3f | 2654 | |
64769240 | 2655 | static int ext4_da_writepages(struct address_space *mapping, |
a1d6cc56 | 2656 | struct writeback_control *wbc) |
64769240 | 2657 | { |
22208ded AK |
2658 | pgoff_t index; |
2659 | int range_whole = 0; | |
61628a3f | 2660 | handle_t *handle = NULL; |
df22291f | 2661 | struct mpage_da_data mpd; |
5e745b04 | 2662 | struct inode *inode = mapping->host; |
22208ded | 2663 | int no_nrwrite_index_update; |
498e5f24 TT |
2664 | int pages_written = 0; |
2665 | long pages_skipped; | |
2acf2c26 | 2666 | int range_cyclic, cycled = 1, io_done = 0; |
5e745b04 | 2667 | int needed_blocks, ret = 0, nr_to_writebump = 0; |
5e745b04 | 2668 | struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb); |
61628a3f | 2669 | |
ba80b101 TT |
2670 | trace_mark(ext4_da_writepages, |
2671 | "dev %s ino %lu nr_t_write %ld " | |
2672 | "pages_skipped %ld range_start %llu " | |
2673 | "range_end %llu nonblocking %d " | |
2674 | "for_kupdate %d for_reclaim %d " | |
2675 | "for_writepages %d range_cyclic %d", | |
2676 | inode->i_sb->s_id, inode->i_ino, | |
2677 | wbc->nr_to_write, wbc->pages_skipped, | |
2678 | (unsigned long long) wbc->range_start, | |
2679 | (unsigned long long) wbc->range_end, | |
2680 | wbc->nonblocking, wbc->for_kupdate, | |
2681 | wbc->for_reclaim, wbc->for_writepages, | |
2682 | wbc->range_cyclic); | |
2683 | ||
61628a3f MC |
2684 | /* |
2685 | * No pages to write? This is mainly a kludge to avoid starting | |
2686 | * a transaction for special inodes like journal inode on last iput() | |
2687 | * because that could violate lock ordering on umount | |
2688 | */ | |
a1d6cc56 | 2689 | if (!mapping->nrpages || !mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) |
61628a3f | 2690 | return 0; |
2a21e37e TT |
2691 | |
2692 | /* | |
2693 | * If the filesystem has aborted, it is read-only, so return | |
2694 | * right away instead of dumping stack traces later on that | |
2695 | * will obscure the real source of the problem. We test | |
2696 | * EXT4_MOUNT_ABORT instead of sb->s_flag's MS_RDONLY because | |
2697 | * the latter could be true if the filesystem is mounted | |
2698 | * read-only, and in that case, ext4_da_writepages should | |
2699 | * *never* be called, so if that ever happens, we would want | |
2700 | * the stack trace. | |
2701 | */ | |
2702 | if (unlikely(sbi->s_mount_opt & EXT4_MOUNT_ABORT)) | |
2703 | return -EROFS; | |
2704 | ||
5e745b04 AK |
2705 | /* |
2706 | * Make sure nr_to_write is >= sbi->s_mb_stream_request | |
2707 | * This make sure small files blocks are allocated in | |
2708 | * single attempt. This ensure that small files | |
2709 | * get less fragmented. | |
2710 | */ | |
2711 | if (wbc->nr_to_write < sbi->s_mb_stream_request) { | |
2712 | nr_to_writebump = sbi->s_mb_stream_request - wbc->nr_to_write; | |
2713 | wbc->nr_to_write = sbi->s_mb_stream_request; | |
2714 | } | |
22208ded AK |
2715 | if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) |
2716 | range_whole = 1; | |
61628a3f | 2717 | |
2acf2c26 AK |
2718 | range_cyclic = wbc->range_cyclic; |
2719 | if (wbc->range_cyclic) { | |
22208ded | 2720 | index = mapping->writeback_index; |
2acf2c26 AK |
2721 | if (index) |
2722 | cycled = 0; | |
2723 | wbc->range_start = index << PAGE_CACHE_SHIFT; | |
2724 | wbc->range_end = LLONG_MAX; | |
2725 | wbc->range_cyclic = 0; | |
2726 | } else | |
22208ded | 2727 | index = wbc->range_start >> PAGE_CACHE_SHIFT; |
a1d6cc56 | 2728 | |
df22291f AK |
2729 | mpd.wbc = wbc; |
2730 | mpd.inode = mapping->host; | |
2731 | ||
22208ded AK |
2732 | /* |
2733 | * we don't want write_cache_pages to update | |
2734 | * nr_to_write and writeback_index | |
2735 | */ | |
2736 | no_nrwrite_index_update = wbc->no_nrwrite_index_update; | |
2737 | wbc->no_nrwrite_index_update = 1; | |
2738 | pages_skipped = wbc->pages_skipped; | |
2739 | ||
2acf2c26 | 2740 | retry: |
22208ded | 2741 | while (!ret && wbc->nr_to_write > 0) { |
a1d6cc56 AK |
2742 | |
2743 | /* | |
2744 | * we insert one extent at a time. So we need | |
2745 | * credit needed for single extent allocation. | |
2746 | * journalled mode is currently not supported | |
2747 | * by delalloc | |
2748 | */ | |
2749 | BUG_ON(ext4_should_journal_data(inode)); | |
525f4ed8 | 2750 | needed_blocks = ext4_da_writepages_trans_blocks(inode); |
a1d6cc56 | 2751 | |
61628a3f MC |
2752 | /* start a new transaction*/ |
2753 | handle = ext4_journal_start(inode, needed_blocks); | |
2754 | if (IS_ERR(handle)) { | |
2755 | ret = PTR_ERR(handle); | |
2a21e37e | 2756 | printk(KERN_CRIT "%s: jbd2_start: " |
a1d6cc56 AK |
2757 | "%ld pages, ino %lu; err %d\n", __func__, |
2758 | wbc->nr_to_write, inode->i_ino, ret); | |
2759 | dump_stack(); | |
61628a3f MC |
2760 | goto out_writepages; |
2761 | } | |
f63e6005 TT |
2762 | |
2763 | /* | |
2764 | * Now call __mpage_da_writepage to find the next | |
2765 | * contiguous region of logical blocks that need | |
2766 | * blocks to be allocated by ext4. We don't actually | |
2767 | * submit the blocks for I/O here, even though | |
2768 | * write_cache_pages thinks it will, and will set the | |
2769 | * pages as clean for write before calling | |
2770 | * __mpage_da_writepage(). | |
2771 | */ | |
2772 | mpd.b_size = 0; | |
2773 | mpd.b_state = 0; | |
2774 | mpd.b_blocknr = 0; | |
2775 | mpd.first_page = 0; | |
2776 | mpd.next_page = 0; | |
2777 | mpd.io_done = 0; | |
2778 | mpd.pages_written = 0; | |
2779 | mpd.retval = 0; | |
2780 | ret = write_cache_pages(mapping, wbc, __mpage_da_writepage, | |
2781 | &mpd); | |
2782 | /* | |
2783 | * If we have a contigous extent of pages and we | |
2784 | * haven't done the I/O yet, map the blocks and submit | |
2785 | * them for I/O. | |
2786 | */ | |
2787 | if (!mpd.io_done && mpd.next_page != mpd.first_page) { | |
2788 | if (mpage_da_map_blocks(&mpd) == 0) | |
2789 | mpage_da_submit_io(&mpd); | |
2790 | mpd.io_done = 1; | |
2791 | ret = MPAGE_DA_EXTENT_TAIL; | |
2792 | } | |
2793 | wbc->nr_to_write -= mpd.pages_written; | |
df22291f | 2794 | |
61628a3f | 2795 | ext4_journal_stop(handle); |
df22291f | 2796 | |
8f64b32e | 2797 | if ((mpd.retval == -ENOSPC) && sbi->s_journal) { |
22208ded AK |
2798 | /* commit the transaction which would |
2799 | * free blocks released in the transaction | |
2800 | * and try again | |
2801 | */ | |
df22291f | 2802 | jbd2_journal_force_commit_nested(sbi->s_journal); |
22208ded AK |
2803 | wbc->pages_skipped = pages_skipped; |
2804 | ret = 0; | |
2805 | } else if (ret == MPAGE_DA_EXTENT_TAIL) { | |
a1d6cc56 AK |
2806 | /* |
2807 | * got one extent now try with | |
2808 | * rest of the pages | |
2809 | */ | |
22208ded AK |
2810 | pages_written += mpd.pages_written; |
2811 | wbc->pages_skipped = pages_skipped; | |
a1d6cc56 | 2812 | ret = 0; |
2acf2c26 | 2813 | io_done = 1; |
22208ded | 2814 | } else if (wbc->nr_to_write) |
61628a3f MC |
2815 | /* |
2816 | * There is no more writeout needed | |
2817 | * or we requested for a noblocking writeout | |
2818 | * and we found the device congested | |
2819 | */ | |
61628a3f | 2820 | break; |
a1d6cc56 | 2821 | } |
2acf2c26 AK |
2822 | if (!io_done && !cycled) { |
2823 | cycled = 1; | |
2824 | index = 0; | |
2825 | wbc->range_start = index << PAGE_CACHE_SHIFT; | |
2826 | wbc->range_end = mapping->writeback_index - 1; | |
2827 | goto retry; | |
2828 | } | |
22208ded AK |
2829 | if (pages_skipped != wbc->pages_skipped) |
2830 | printk(KERN_EMERG "This should not happen leaving %s " | |
2831 | "with nr_to_write = %ld ret = %d\n", | |
2832 | __func__, wbc->nr_to_write, ret); | |
2833 | ||
2834 | /* Update index */ | |
2835 | index += pages_written; | |
2acf2c26 | 2836 | wbc->range_cyclic = range_cyclic; |
22208ded AK |
2837 | if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) |
2838 | /* | |
2839 | * set the writeback_index so that range_cyclic | |
2840 | * mode will write it back later | |
2841 | */ | |
2842 | mapping->writeback_index = index; | |
a1d6cc56 | 2843 | |
61628a3f | 2844 | out_writepages: |
22208ded AK |
2845 | if (!no_nrwrite_index_update) |
2846 | wbc->no_nrwrite_index_update = 0; | |
2847 | wbc->nr_to_write -= nr_to_writebump; | |
ba80b101 TT |
2848 | trace_mark(ext4_da_writepage_result, |
2849 | "dev %s ino %lu ret %d pages_written %d " | |
2850 | "pages_skipped %ld congestion %d " | |
2851 | "more_io %d no_nrwrite_index_update %d", | |
2852 | inode->i_sb->s_id, inode->i_ino, ret, | |
2853 | pages_written, wbc->pages_skipped, | |
2854 | wbc->encountered_congestion, wbc->more_io, | |
2855 | wbc->no_nrwrite_index_update); | |
61628a3f | 2856 | return ret; |
64769240 AT |
2857 | } |
2858 | ||
79f0be8d AK |
2859 | #define FALL_BACK_TO_NONDELALLOC 1 |
2860 | static int ext4_nonda_switch(struct super_block *sb) | |
2861 | { | |
2862 | s64 free_blocks, dirty_blocks; | |
2863 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2864 | ||
2865 | /* | |
2866 | * switch to non delalloc mode if we are running low | |
2867 | * on free block. The free block accounting via percpu | |
179f7ebf | 2868 | * counters can get slightly wrong with percpu_counter_batch getting |
79f0be8d AK |
2869 | * accumulated on each CPU without updating global counters |
2870 | * Delalloc need an accurate free block accounting. So switch | |
2871 | * to non delalloc when we are near to error range. | |
2872 | */ | |
2873 | free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter); | |
2874 | dirty_blocks = percpu_counter_read_positive(&sbi->s_dirtyblocks_counter); | |
2875 | if (2 * free_blocks < 3 * dirty_blocks || | |
2876 | free_blocks < (dirty_blocks + EXT4_FREEBLOCKS_WATERMARK)) { | |
2877 | /* | |
2878 | * free block count is less that 150% of dirty blocks | |
2879 | * or free blocks is less that watermark | |
2880 | */ | |
2881 | return 1; | |
2882 | } | |
2883 | return 0; | |
2884 | } | |
2885 | ||
64769240 AT |
2886 | static int ext4_da_write_begin(struct file *file, struct address_space *mapping, |
2887 | loff_t pos, unsigned len, unsigned flags, | |
2888 | struct page **pagep, void **fsdata) | |
2889 | { | |
d2a17637 | 2890 | int ret, retries = 0; |
64769240 AT |
2891 | struct page *page; |
2892 | pgoff_t index; | |
2893 | unsigned from, to; | |
2894 | struct inode *inode = mapping->host; | |
2895 | handle_t *handle; | |
2896 | ||
2897 | index = pos >> PAGE_CACHE_SHIFT; | |
2898 | from = pos & (PAGE_CACHE_SIZE - 1); | |
2899 | to = from + len; | |
79f0be8d AK |
2900 | |
2901 | if (ext4_nonda_switch(inode->i_sb)) { | |
2902 | *fsdata = (void *)FALL_BACK_TO_NONDELALLOC; | |
2903 | return ext4_write_begin(file, mapping, pos, | |
2904 | len, flags, pagep, fsdata); | |
2905 | } | |
2906 | *fsdata = (void *)0; | |
ba80b101 TT |
2907 | |
2908 | trace_mark(ext4_da_write_begin, | |
2909 | "dev %s ino %lu pos %llu len %u flags %u", | |
2910 | inode->i_sb->s_id, inode->i_ino, | |
2911 | (unsigned long long) pos, len, flags); | |
d2a17637 | 2912 | retry: |
64769240 AT |
2913 | /* |
2914 | * With delayed allocation, we don't log the i_disksize update | |
2915 | * if there is delayed block allocation. But we still need | |
2916 | * to journalling the i_disksize update if writes to the end | |
2917 | * of file which has an already mapped buffer. | |
2918 | */ | |
2919 | handle = ext4_journal_start(inode, 1); | |
2920 | if (IS_ERR(handle)) { | |
2921 | ret = PTR_ERR(handle); | |
2922 | goto out; | |
2923 | } | |
ebd3610b JK |
2924 | /* We cannot recurse into the filesystem as the transaction is already |
2925 | * started */ | |
2926 | flags |= AOP_FLAG_NOFS; | |
64769240 | 2927 | |
54566b2c | 2928 | page = grab_cache_page_write_begin(mapping, index, flags); |
d5a0d4f7 ES |
2929 | if (!page) { |
2930 | ext4_journal_stop(handle); | |
2931 | ret = -ENOMEM; | |
2932 | goto out; | |
2933 | } | |
64769240 AT |
2934 | *pagep = page; |
2935 | ||
2936 | ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, | |
b920c755 | 2937 | ext4_da_get_block_prep); |
64769240 AT |
2938 | if (ret < 0) { |
2939 | unlock_page(page); | |
2940 | ext4_journal_stop(handle); | |
2941 | page_cache_release(page); | |
ae4d5372 AK |
2942 | /* |
2943 | * block_write_begin may have instantiated a few blocks | |
2944 | * outside i_size. Trim these off again. Don't need | |
2945 | * i_size_read because we hold i_mutex. | |
2946 | */ | |
2947 | if (pos + len > inode->i_size) | |
2948 | vmtruncate(inode, inode->i_size); | |
64769240 AT |
2949 | } |
2950 | ||
d2a17637 MC |
2951 | if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) |
2952 | goto retry; | |
64769240 AT |
2953 | out: |
2954 | return ret; | |
2955 | } | |
2956 | ||
632eaeab MC |
2957 | /* |
2958 | * Check if we should update i_disksize | |
2959 | * when write to the end of file but not require block allocation | |
2960 | */ | |
2961 | static int ext4_da_should_update_i_disksize(struct page *page, | |
2962 | unsigned long offset) | |
2963 | { | |
2964 | struct buffer_head *bh; | |
2965 | struct inode *inode = page->mapping->host; | |
2966 | unsigned int idx; | |
2967 | int i; | |
2968 | ||
2969 | bh = page_buffers(page); | |
2970 | idx = offset >> inode->i_blkbits; | |
2971 | ||
af5bc92d | 2972 | for (i = 0; i < idx; i++) |
632eaeab MC |
2973 | bh = bh->b_this_page; |
2974 | ||
29fa89d0 | 2975 | if (!buffer_mapped(bh) || (buffer_delay(bh)) || buffer_unwritten(bh)) |
632eaeab MC |
2976 | return 0; |
2977 | return 1; | |
2978 | } | |
2979 | ||
64769240 AT |
2980 | static int ext4_da_write_end(struct file *file, |
2981 | struct address_space *mapping, | |
2982 | loff_t pos, unsigned len, unsigned copied, | |
2983 | struct page *page, void *fsdata) | |
2984 | { | |
2985 | struct inode *inode = mapping->host; | |
2986 | int ret = 0, ret2; | |
2987 | handle_t *handle = ext4_journal_current_handle(); | |
2988 | loff_t new_i_size; | |
632eaeab | 2989 | unsigned long start, end; |
79f0be8d AK |
2990 | int write_mode = (int)(unsigned long)fsdata; |
2991 | ||
2992 | if (write_mode == FALL_BACK_TO_NONDELALLOC) { | |
2993 | if (ext4_should_order_data(inode)) { | |
2994 | return ext4_ordered_write_end(file, mapping, pos, | |
2995 | len, copied, page, fsdata); | |
2996 | } else if (ext4_should_writeback_data(inode)) { | |
2997 | return ext4_writeback_write_end(file, mapping, pos, | |
2998 | len, copied, page, fsdata); | |
2999 | } else { | |
3000 | BUG(); | |
3001 | } | |
3002 | } | |
632eaeab | 3003 | |
ba80b101 TT |
3004 | trace_mark(ext4_da_write_end, |
3005 | "dev %s ino %lu pos %llu len %u copied %u", | |
3006 | inode->i_sb->s_id, inode->i_ino, | |
3007 | (unsigned long long) pos, len, copied); | |
632eaeab | 3008 | start = pos & (PAGE_CACHE_SIZE - 1); |
af5bc92d | 3009 | end = start + copied - 1; |
64769240 AT |
3010 | |
3011 | /* | |
3012 | * generic_write_end() will run mark_inode_dirty() if i_size | |
3013 | * changes. So let's piggyback the i_disksize mark_inode_dirty | |
3014 | * into that. | |
3015 | */ | |
3016 | ||
3017 | new_i_size = pos + copied; | |
632eaeab MC |
3018 | if (new_i_size > EXT4_I(inode)->i_disksize) { |
3019 | if (ext4_da_should_update_i_disksize(page, end)) { | |
3020 | down_write(&EXT4_I(inode)->i_data_sem); | |
3021 | if (new_i_size > EXT4_I(inode)->i_disksize) { | |
3022 | /* | |
3023 | * Updating i_disksize when extending file | |
3024 | * without needing block allocation | |
3025 | */ | |
3026 | if (ext4_should_order_data(inode)) | |
3027 | ret = ext4_jbd2_file_inode(handle, | |
3028 | inode); | |
64769240 | 3029 | |
632eaeab MC |
3030 | EXT4_I(inode)->i_disksize = new_i_size; |
3031 | } | |
3032 | up_write(&EXT4_I(inode)->i_data_sem); | |
cf17fea6 AK |
3033 | /* We need to mark inode dirty even if |
3034 | * new_i_size is less that inode->i_size | |
3035 | * bu greater than i_disksize.(hint delalloc) | |
3036 | */ | |
3037 | ext4_mark_inode_dirty(handle, inode); | |
64769240 | 3038 | } |
632eaeab | 3039 | } |
64769240 AT |
3040 | ret2 = generic_write_end(file, mapping, pos, len, copied, |
3041 | page, fsdata); | |
3042 | copied = ret2; | |
3043 | if (ret2 < 0) | |
3044 | ret = ret2; | |
3045 | ret2 = ext4_journal_stop(handle); | |
3046 | if (!ret) | |
3047 | ret = ret2; | |
3048 | ||
3049 | return ret ? ret : copied; | |
3050 | } | |
3051 | ||
3052 | static void ext4_da_invalidatepage(struct page *page, unsigned long offset) | |
3053 | { | |
64769240 AT |
3054 | /* |
3055 | * Drop reserved blocks | |
3056 | */ | |
3057 | BUG_ON(!PageLocked(page)); | |
3058 | if (!page_has_buffers(page)) | |
3059 | goto out; | |
3060 | ||
d2a17637 | 3061 | ext4_da_page_release_reservation(page, offset); |
64769240 AT |
3062 | |
3063 | out: | |
3064 | ext4_invalidatepage(page, offset); | |
3065 | ||
3066 | return; | |
3067 | } | |
3068 | ||
ccd2506b TT |
3069 | /* |
3070 | * Force all delayed allocation blocks to be allocated for a given inode. | |
3071 | */ | |
3072 | int ext4_alloc_da_blocks(struct inode *inode) | |
3073 | { | |
3074 | if (!EXT4_I(inode)->i_reserved_data_blocks && | |
3075 | !EXT4_I(inode)->i_reserved_meta_blocks) | |
3076 | return 0; | |
3077 | ||
3078 | /* | |
3079 | * We do something simple for now. The filemap_flush() will | |
3080 | * also start triggering a write of the data blocks, which is | |
3081 | * not strictly speaking necessary (and for users of | |
3082 | * laptop_mode, not even desirable). However, to do otherwise | |
3083 | * would require replicating code paths in: | |
3084 | * | |
3085 | * ext4_da_writepages() -> | |
3086 | * write_cache_pages() ---> (via passed in callback function) | |
3087 | * __mpage_da_writepage() --> | |
3088 | * mpage_add_bh_to_extent() | |
3089 | * mpage_da_map_blocks() | |
3090 | * | |
3091 | * The problem is that write_cache_pages(), located in | |
3092 | * mm/page-writeback.c, marks pages clean in preparation for | |
3093 | * doing I/O, which is not desirable if we're not planning on | |
3094 | * doing I/O at all. | |
3095 | * | |
3096 | * We could call write_cache_pages(), and then redirty all of | |
3097 | * the pages by calling redirty_page_for_writeback() but that | |
3098 | * would be ugly in the extreme. So instead we would need to | |
3099 | * replicate parts of the code in the above functions, | |
3100 | * simplifying them becuase we wouldn't actually intend to | |
3101 | * write out the pages, but rather only collect contiguous | |
3102 | * logical block extents, call the multi-block allocator, and | |
3103 | * then update the buffer heads with the block allocations. | |
3104 | * | |
3105 | * For now, though, we'll cheat by calling filemap_flush(), | |
3106 | * which will map the blocks, and start the I/O, but not | |
3107 | * actually wait for the I/O to complete. | |
3108 | */ | |
3109 | return filemap_flush(inode->i_mapping); | |
3110 | } | |
64769240 | 3111 | |
ac27a0ec DK |
3112 | /* |
3113 | * bmap() is special. It gets used by applications such as lilo and by | |
3114 | * the swapper to find the on-disk block of a specific piece of data. | |
3115 | * | |
3116 | * Naturally, this is dangerous if the block concerned is still in the | |
617ba13b | 3117 | * journal. If somebody makes a swapfile on an ext4 data-journaling |
ac27a0ec DK |
3118 | * filesystem and enables swap, then they may get a nasty shock when the |
3119 | * data getting swapped to that swapfile suddenly gets overwritten by | |
3120 | * the original zero's written out previously to the journal and | |
3121 | * awaiting writeback in the kernel's buffer cache. | |
3122 | * | |
3123 | * So, if we see any bmap calls here on a modified, data-journaled file, | |
3124 | * take extra steps to flush any blocks which might be in the cache. | |
3125 | */ | |
617ba13b | 3126 | static sector_t ext4_bmap(struct address_space *mapping, sector_t block) |
ac27a0ec DK |
3127 | { |
3128 | struct inode *inode = mapping->host; | |
3129 | journal_t *journal; | |
3130 | int err; | |
3131 | ||
64769240 AT |
3132 | if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) && |
3133 | test_opt(inode->i_sb, DELALLOC)) { | |
3134 | /* | |
3135 | * With delalloc we want to sync the file | |
3136 | * so that we can make sure we allocate | |
3137 | * blocks for file | |
3138 | */ | |
3139 | filemap_write_and_wait(mapping); | |
3140 | } | |
3141 | ||
0390131b | 3142 | if (EXT4_JOURNAL(inode) && EXT4_I(inode)->i_state & EXT4_STATE_JDATA) { |
ac27a0ec DK |
3143 | /* |
3144 | * This is a REALLY heavyweight approach, but the use of | |
3145 | * bmap on dirty files is expected to be extremely rare: | |
3146 | * only if we run lilo or swapon on a freshly made file | |
3147 | * do we expect this to happen. | |
3148 | * | |
3149 | * (bmap requires CAP_SYS_RAWIO so this does not | |
3150 | * represent an unprivileged user DOS attack --- we'd be | |
3151 | * in trouble if mortal users could trigger this path at | |
3152 | * will.) | |
3153 | * | |
617ba13b | 3154 | * NB. EXT4_STATE_JDATA is not set on files other than |
ac27a0ec DK |
3155 | * regular files. If somebody wants to bmap a directory |
3156 | * or symlink and gets confused because the buffer | |
3157 | * hasn't yet been flushed to disk, they deserve | |
3158 | * everything they get. | |
3159 | */ | |
3160 | ||
617ba13b MC |
3161 | EXT4_I(inode)->i_state &= ~EXT4_STATE_JDATA; |
3162 | journal = EXT4_JOURNAL(inode); | |
dab291af MC |
3163 | jbd2_journal_lock_updates(journal); |
3164 | err = jbd2_journal_flush(journal); | |
3165 | jbd2_journal_unlock_updates(journal); | |
ac27a0ec DK |
3166 | |
3167 | if (err) | |
3168 | return 0; | |
3169 | } | |
3170 | ||
af5bc92d | 3171 | return generic_block_bmap(mapping, block, ext4_get_block); |
ac27a0ec DK |
3172 | } |
3173 | ||
3174 | static int bget_one(handle_t *handle, struct buffer_head *bh) | |
3175 | { | |
3176 | get_bh(bh); | |
3177 | return 0; | |
3178 | } | |
3179 | ||
3180 | static int bput_one(handle_t *handle, struct buffer_head *bh) | |
3181 | { | |
3182 | put_bh(bh); | |
3183 | return 0; | |
3184 | } | |
3185 | ||
ac27a0ec | 3186 | /* |
678aaf48 JK |
3187 | * Note that we don't need to start a transaction unless we're journaling data |
3188 | * because we should have holes filled from ext4_page_mkwrite(). We even don't | |
3189 | * need to file the inode to the transaction's list in ordered mode because if | |
3190 | * we are writing back data added by write(), the inode is already there and if | |
3191 | * we are writing back data modified via mmap(), noone guarantees in which | |
3192 | * transaction the data will hit the disk. In case we are journaling data, we | |
3193 | * cannot start transaction directly because transaction start ranks above page | |
3194 | * lock so we have to do some magic. | |
ac27a0ec | 3195 | * |
678aaf48 | 3196 | * In all journaling modes block_write_full_page() will start the I/O. |
ac27a0ec DK |
3197 | * |
3198 | * Problem: | |
3199 | * | |
617ba13b MC |
3200 | * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() -> |
3201 | * ext4_writepage() | |
ac27a0ec DK |
3202 | * |
3203 | * Similar for: | |
3204 | * | |
617ba13b | 3205 | * ext4_file_write() -> generic_file_write() -> __alloc_pages() -> ... |
ac27a0ec | 3206 | * |
617ba13b | 3207 | * Same applies to ext4_get_block(). We will deadlock on various things like |
0e855ac8 | 3208 | * lock_journal and i_data_sem |
ac27a0ec DK |
3209 | * |
3210 | * Setting PF_MEMALLOC here doesn't work - too many internal memory | |
3211 | * allocations fail. | |
3212 | * | |
3213 | * 16May01: If we're reentered then journal_current_handle() will be | |
3214 | * non-zero. We simply *return*. | |
3215 | * | |
3216 | * 1 July 2001: @@@ FIXME: | |
3217 | * In journalled data mode, a data buffer may be metadata against the | |
3218 | * current transaction. But the same file is part of a shared mapping | |
3219 | * and someone does a writepage() on it. | |
3220 | * | |
3221 | * We will move the buffer onto the async_data list, but *after* it has | |
3222 | * been dirtied. So there's a small window where we have dirty data on | |
3223 | * BJ_Metadata. | |
3224 | * | |
3225 | * Note that this only applies to the last partial page in the file. The | |
3226 | * bit which block_write_full_page() uses prepare/commit for. (That's | |
3227 | * broken code anyway: it's wrong for msync()). | |
3228 | * | |
3229 | * It's a rare case: affects the final partial page, for journalled data | |
3230 | * where the file is subject to bith write() and writepage() in the same | |
3231 | * transction. To fix it we'll need a custom block_write_full_page(). | |
3232 | * We'll probably need that anyway for journalling writepage() output. | |
3233 | * | |
3234 | * We don't honour synchronous mounts for writepage(). That would be | |
3235 | * disastrous. Any write() or metadata operation will sync the fs for | |
3236 | * us. | |
3237 | * | |
ac27a0ec | 3238 | */ |
678aaf48 | 3239 | static int __ext4_normal_writepage(struct page *page, |
cf108bca JK |
3240 | struct writeback_control *wbc) |
3241 | { | |
3242 | struct inode *inode = page->mapping->host; | |
3243 | ||
3244 | if (test_opt(inode->i_sb, NOBH)) | |
b920c755 | 3245 | return nobh_writepage(page, noalloc_get_block_write, wbc); |
cf108bca | 3246 | else |
b920c755 TT |
3247 | return block_write_full_page(page, noalloc_get_block_write, |
3248 | wbc); | |
cf108bca JK |
3249 | } |
3250 | ||
678aaf48 | 3251 | static int ext4_normal_writepage(struct page *page, |
ac27a0ec DK |
3252 | struct writeback_control *wbc) |
3253 | { | |
3254 | struct inode *inode = page->mapping->host; | |
cf108bca JK |
3255 | loff_t size = i_size_read(inode); |
3256 | loff_t len; | |
3257 | ||
ba80b101 TT |
3258 | trace_mark(ext4_normal_writepage, |
3259 | "dev %s ino %lu page_index %lu", | |
3260 | inode->i_sb->s_id, inode->i_ino, page->index); | |
cf108bca | 3261 | J_ASSERT(PageLocked(page)); |
cf108bca JK |
3262 | if (page->index == size >> PAGE_CACHE_SHIFT) |
3263 | len = size & ~PAGE_CACHE_MASK; | |
3264 | else | |
3265 | len = PAGE_CACHE_SIZE; | |
f0e6c985 AK |
3266 | |
3267 | if (page_has_buffers(page)) { | |
3268 | /* if page has buffers it should all be mapped | |
3269 | * and allocated. If there are not buffers attached | |
3270 | * to the page we know the page is dirty but it lost | |
3271 | * buffers. That means that at some moment in time | |
3272 | * after write_begin() / write_end() has been called | |
3273 | * all buffers have been clean and thus they must have been | |
3274 | * written at least once. So they are all mapped and we can | |
3275 | * happily proceed with mapping them and writing the page. | |
3276 | */ | |
3277 | BUG_ON(walk_page_buffers(NULL, page_buffers(page), 0, len, NULL, | |
3278 | ext4_bh_unmapped_or_delay)); | |
3279 | } | |
cf108bca JK |
3280 | |
3281 | if (!ext4_journal_current_handle()) | |
678aaf48 | 3282 | return __ext4_normal_writepage(page, wbc); |
cf108bca JK |
3283 | |
3284 | redirty_page_for_writepage(wbc, page); | |
3285 | unlock_page(page); | |
3286 | return 0; | |
3287 | } | |
3288 | ||
3289 | static int __ext4_journalled_writepage(struct page *page, | |
3290 | struct writeback_control *wbc) | |
3291 | { | |
3292 | struct address_space *mapping = page->mapping; | |
3293 | struct inode *inode = mapping->host; | |
3294 | struct buffer_head *page_bufs; | |
ac27a0ec DK |
3295 | handle_t *handle = NULL; |
3296 | int ret = 0; | |
3297 | int err; | |
3298 | ||
f0e6c985 | 3299 | ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE, |
b920c755 | 3300 | noalloc_get_block_write); |
cf108bca JK |
3301 | if (ret != 0) |
3302 | goto out_unlock; | |
3303 | ||
3304 | page_bufs = page_buffers(page); | |
3305 | walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE, NULL, | |
3306 | bget_one); | |
3307 | /* As soon as we unlock the page, it can go away, but we have | |
3308 | * references to buffers so we are safe */ | |
3309 | unlock_page(page); | |
ac27a0ec | 3310 | |
617ba13b | 3311 | handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode)); |
ac27a0ec DK |
3312 | if (IS_ERR(handle)) { |
3313 | ret = PTR_ERR(handle); | |
cf108bca | 3314 | goto out; |
ac27a0ec DK |
3315 | } |
3316 | ||
cf108bca JK |
3317 | ret = walk_page_buffers(handle, page_bufs, 0, |
3318 | PAGE_CACHE_SIZE, NULL, do_journal_get_write_access); | |
ac27a0ec | 3319 | |
cf108bca JK |
3320 | err = walk_page_buffers(handle, page_bufs, 0, |
3321 | PAGE_CACHE_SIZE, NULL, write_end_fn); | |
3322 | if (ret == 0) | |
3323 | ret = err; | |
617ba13b | 3324 | err = ext4_journal_stop(handle); |
ac27a0ec DK |
3325 | if (!ret) |
3326 | ret = err; | |
ac27a0ec | 3327 | |
cf108bca JK |
3328 | walk_page_buffers(handle, page_bufs, 0, |
3329 | PAGE_CACHE_SIZE, NULL, bput_one); | |
3330 | EXT4_I(inode)->i_state |= EXT4_STATE_JDATA; | |
3331 | goto out; | |
3332 | ||
3333 | out_unlock: | |
ac27a0ec | 3334 | unlock_page(page); |
cf108bca | 3335 | out: |
ac27a0ec DK |
3336 | return ret; |
3337 | } | |
3338 | ||
617ba13b | 3339 | static int ext4_journalled_writepage(struct page *page, |
ac27a0ec DK |
3340 | struct writeback_control *wbc) |
3341 | { | |
3342 | struct inode *inode = page->mapping->host; | |
cf108bca JK |
3343 | loff_t size = i_size_read(inode); |
3344 | loff_t len; | |
ac27a0ec | 3345 | |
ba80b101 TT |
3346 | trace_mark(ext4_journalled_writepage, |
3347 | "dev %s ino %lu page_index %lu", | |
3348 | inode->i_sb->s_id, inode->i_ino, page->index); | |
cf108bca | 3349 | J_ASSERT(PageLocked(page)); |
cf108bca JK |
3350 | if (page->index == size >> PAGE_CACHE_SHIFT) |
3351 | len = size & ~PAGE_CACHE_MASK; | |
3352 | else | |
3353 | len = PAGE_CACHE_SIZE; | |
f0e6c985 AK |
3354 | |
3355 | if (page_has_buffers(page)) { | |
3356 | /* if page has buffers it should all be mapped | |
3357 | * and allocated. If there are not buffers attached | |
3358 | * to the page we know the page is dirty but it lost | |
3359 | * buffers. That means that at some moment in time | |
3360 | * after write_begin() / write_end() has been called | |
3361 | * all buffers have been clean and thus they must have been | |
3362 | * written at least once. So they are all mapped and we can | |
3363 | * happily proceed with mapping them and writing the page. | |
3364 | */ | |
3365 | BUG_ON(walk_page_buffers(NULL, page_buffers(page), 0, len, NULL, | |
3366 | ext4_bh_unmapped_or_delay)); | |
3367 | } | |
ac27a0ec | 3368 | |
cf108bca | 3369 | if (ext4_journal_current_handle()) |
ac27a0ec | 3370 | goto no_write; |
ac27a0ec | 3371 | |
cf108bca | 3372 | if (PageChecked(page)) { |
ac27a0ec DK |
3373 | /* |
3374 | * It's mmapped pagecache. Add buffers and journal it. There | |
3375 | * doesn't seem much point in redirtying the page here. | |
3376 | */ | |
3377 | ClearPageChecked(page); | |
cf108bca | 3378 | return __ext4_journalled_writepage(page, wbc); |
ac27a0ec DK |
3379 | } else { |
3380 | /* | |
3381 | * It may be a page full of checkpoint-mode buffers. We don't | |
3382 | * really know unless we go poke around in the buffer_heads. | |
3383 | * But block_write_full_page will do the right thing. | |
3384 | */ | |
b920c755 TT |
3385 | return block_write_full_page(page, noalloc_get_block_write, |
3386 | wbc); | |
ac27a0ec | 3387 | } |
ac27a0ec DK |
3388 | no_write: |
3389 | redirty_page_for_writepage(wbc, page); | |
ac27a0ec | 3390 | unlock_page(page); |
cf108bca | 3391 | return 0; |
ac27a0ec DK |
3392 | } |
3393 | ||
617ba13b | 3394 | static int ext4_readpage(struct file *file, struct page *page) |
ac27a0ec | 3395 | { |
617ba13b | 3396 | return mpage_readpage(page, ext4_get_block); |
ac27a0ec DK |
3397 | } |
3398 | ||
3399 | static int | |
617ba13b | 3400 | ext4_readpages(struct file *file, struct address_space *mapping, |
ac27a0ec DK |
3401 | struct list_head *pages, unsigned nr_pages) |
3402 | { | |
617ba13b | 3403 | return mpage_readpages(mapping, pages, nr_pages, ext4_get_block); |
ac27a0ec DK |
3404 | } |
3405 | ||
617ba13b | 3406 | static void ext4_invalidatepage(struct page *page, unsigned long offset) |
ac27a0ec | 3407 | { |
617ba13b | 3408 | journal_t *journal = EXT4_JOURNAL(page->mapping->host); |
ac27a0ec DK |
3409 | |
3410 | /* | |
3411 | * If it's a full truncate we just forget about the pending dirtying | |
3412 | */ | |
3413 | if (offset == 0) | |
3414 | ClearPageChecked(page); | |
3415 | ||
0390131b FM |
3416 | if (journal) |
3417 | jbd2_journal_invalidatepage(journal, page, offset); | |
3418 | else | |
3419 | block_invalidatepage(page, offset); | |
ac27a0ec DK |
3420 | } |
3421 | ||
617ba13b | 3422 | static int ext4_releasepage(struct page *page, gfp_t wait) |
ac27a0ec | 3423 | { |
617ba13b | 3424 | journal_t *journal = EXT4_JOURNAL(page->mapping->host); |
ac27a0ec DK |
3425 | |
3426 | WARN_ON(PageChecked(page)); | |
3427 | if (!page_has_buffers(page)) | |
3428 | return 0; | |
0390131b FM |
3429 | if (journal) |
3430 | return jbd2_journal_try_to_free_buffers(journal, page, wait); | |
3431 | else | |
3432 | return try_to_free_buffers(page); | |
ac27a0ec DK |
3433 | } |
3434 | ||
3435 | /* | |
3436 | * If the O_DIRECT write will extend the file then add this inode to the | |
3437 | * orphan list. So recovery will truncate it back to the original size | |
3438 | * if the machine crashes during the write. | |
3439 | * | |
3440 | * If the O_DIRECT write is intantiating holes inside i_size and the machine | |
7fb5409d JK |
3441 | * crashes then stale disk data _may_ be exposed inside the file. But current |
3442 | * VFS code falls back into buffered path in that case so we are safe. | |
ac27a0ec | 3443 | */ |
617ba13b | 3444 | static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb, |
ac27a0ec DK |
3445 | const struct iovec *iov, loff_t offset, |
3446 | unsigned long nr_segs) | |
3447 | { | |
3448 | struct file *file = iocb->ki_filp; | |
3449 | struct inode *inode = file->f_mapping->host; | |
617ba13b | 3450 | struct ext4_inode_info *ei = EXT4_I(inode); |
7fb5409d | 3451 | handle_t *handle; |
ac27a0ec DK |
3452 | ssize_t ret; |
3453 | int orphan = 0; | |
3454 | size_t count = iov_length(iov, nr_segs); | |
3455 | ||
3456 | if (rw == WRITE) { | |
3457 | loff_t final_size = offset + count; | |
3458 | ||
ac27a0ec | 3459 | if (final_size > inode->i_size) { |
7fb5409d JK |
3460 | /* Credits for sb + inode write */ |
3461 | handle = ext4_journal_start(inode, 2); | |
3462 | if (IS_ERR(handle)) { | |
3463 | ret = PTR_ERR(handle); | |
3464 | goto out; | |
3465 | } | |
617ba13b | 3466 | ret = ext4_orphan_add(handle, inode); |
7fb5409d JK |
3467 | if (ret) { |
3468 | ext4_journal_stop(handle); | |
3469 | goto out; | |
3470 | } | |
ac27a0ec DK |
3471 | orphan = 1; |
3472 | ei->i_disksize = inode->i_size; | |
7fb5409d | 3473 | ext4_journal_stop(handle); |
ac27a0ec DK |
3474 | } |
3475 | } | |
3476 | ||
3477 | ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov, | |
3478 | offset, nr_segs, | |
617ba13b | 3479 | ext4_get_block, NULL); |
ac27a0ec | 3480 | |
7fb5409d | 3481 | if (orphan) { |
ac27a0ec DK |
3482 | int err; |
3483 | ||
7fb5409d JK |
3484 | /* Credits for sb + inode write */ |
3485 | handle = ext4_journal_start(inode, 2); | |
3486 | if (IS_ERR(handle)) { | |
3487 | /* This is really bad luck. We've written the data | |
3488 | * but cannot extend i_size. Bail out and pretend | |
3489 | * the write failed... */ | |
3490 | ret = PTR_ERR(handle); | |
3491 | goto out; | |
3492 | } | |
3493 | if (inode->i_nlink) | |
617ba13b | 3494 | ext4_orphan_del(handle, inode); |
7fb5409d | 3495 | if (ret > 0) { |
ac27a0ec DK |
3496 | loff_t end = offset + ret; |
3497 | if (end > inode->i_size) { | |
3498 | ei->i_disksize = end; | |
3499 | i_size_write(inode, end); | |
3500 | /* | |
3501 | * We're going to return a positive `ret' | |
3502 | * here due to non-zero-length I/O, so there's | |
3503 | * no way of reporting error returns from | |
617ba13b | 3504 | * ext4_mark_inode_dirty() to userspace. So |
ac27a0ec DK |
3505 | * ignore it. |
3506 | */ | |
617ba13b | 3507 | ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
3508 | } |
3509 | } | |
617ba13b | 3510 | err = ext4_journal_stop(handle); |
ac27a0ec DK |
3511 | if (ret == 0) |
3512 | ret = err; | |
3513 | } | |
3514 | out: | |
3515 | return ret; | |
3516 | } | |
3517 | ||
3518 | /* | |
617ba13b | 3519 | * Pages can be marked dirty completely asynchronously from ext4's journalling |
ac27a0ec DK |
3520 | * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do |
3521 | * much here because ->set_page_dirty is called under VFS locks. The page is | |
3522 | * not necessarily locked. | |
3523 | * | |
3524 | * We cannot just dirty the page and leave attached buffers clean, because the | |
3525 | * buffers' dirty state is "definitive". We cannot just set the buffers dirty | |
3526 | * or jbddirty because all the journalling code will explode. | |
3527 | * | |
3528 | * So what we do is to mark the page "pending dirty" and next time writepage | |
3529 | * is called, propagate that into the buffers appropriately. | |
3530 | */ | |
617ba13b | 3531 | static int ext4_journalled_set_page_dirty(struct page *page) |
ac27a0ec DK |
3532 | { |
3533 | SetPageChecked(page); | |
3534 | return __set_page_dirty_nobuffers(page); | |
3535 | } | |
3536 | ||
617ba13b | 3537 | static const struct address_space_operations ext4_ordered_aops = { |
8ab22b9a HH |
3538 | .readpage = ext4_readpage, |
3539 | .readpages = ext4_readpages, | |
3540 | .writepage = ext4_normal_writepage, | |
3541 | .sync_page = block_sync_page, | |
3542 | .write_begin = ext4_write_begin, | |
3543 | .write_end = ext4_ordered_write_end, | |
3544 | .bmap = ext4_bmap, | |
3545 | .invalidatepage = ext4_invalidatepage, | |
3546 | .releasepage = ext4_releasepage, | |
3547 | .direct_IO = ext4_direct_IO, | |
3548 | .migratepage = buffer_migrate_page, | |
3549 | .is_partially_uptodate = block_is_partially_uptodate, | |
ac27a0ec DK |
3550 | }; |
3551 | ||
617ba13b | 3552 | static const struct address_space_operations ext4_writeback_aops = { |
8ab22b9a HH |
3553 | .readpage = ext4_readpage, |
3554 | .readpages = ext4_readpages, | |
3555 | .writepage = ext4_normal_writepage, | |
3556 | .sync_page = block_sync_page, | |
3557 | .write_begin = ext4_write_begin, | |
3558 | .write_end = ext4_writeback_write_end, | |
3559 | .bmap = ext4_bmap, | |
3560 | .invalidatepage = ext4_invalidatepage, | |
3561 | .releasepage = ext4_releasepage, | |
3562 | .direct_IO = ext4_direct_IO, | |
3563 | .migratepage = buffer_migrate_page, | |
3564 | .is_partially_uptodate = block_is_partially_uptodate, | |
ac27a0ec DK |
3565 | }; |
3566 | ||
617ba13b | 3567 | static const struct address_space_operations ext4_journalled_aops = { |
8ab22b9a HH |
3568 | .readpage = ext4_readpage, |
3569 | .readpages = ext4_readpages, | |
3570 | .writepage = ext4_journalled_writepage, | |
3571 | .sync_page = block_sync_page, | |
3572 | .write_begin = ext4_write_begin, | |
3573 | .write_end = ext4_journalled_write_end, | |
3574 | .set_page_dirty = ext4_journalled_set_page_dirty, | |
3575 | .bmap = ext4_bmap, | |
3576 | .invalidatepage = ext4_invalidatepage, | |
3577 | .releasepage = ext4_releasepage, | |
3578 | .is_partially_uptodate = block_is_partially_uptodate, | |
ac27a0ec DK |
3579 | }; |
3580 | ||
64769240 | 3581 | static const struct address_space_operations ext4_da_aops = { |
8ab22b9a HH |
3582 | .readpage = ext4_readpage, |
3583 | .readpages = ext4_readpages, | |
3584 | .writepage = ext4_da_writepage, | |
3585 | .writepages = ext4_da_writepages, | |
3586 | .sync_page = block_sync_page, | |
3587 | .write_begin = ext4_da_write_begin, | |
3588 | .write_end = ext4_da_write_end, | |
3589 | .bmap = ext4_bmap, | |
3590 | .invalidatepage = ext4_da_invalidatepage, | |
3591 | .releasepage = ext4_releasepage, | |
3592 | .direct_IO = ext4_direct_IO, | |
3593 | .migratepage = buffer_migrate_page, | |
3594 | .is_partially_uptodate = block_is_partially_uptodate, | |
64769240 AT |
3595 | }; |
3596 | ||
617ba13b | 3597 | void ext4_set_aops(struct inode *inode) |
ac27a0ec | 3598 | { |
cd1aac32 AK |
3599 | if (ext4_should_order_data(inode) && |
3600 | test_opt(inode->i_sb, DELALLOC)) | |
3601 | inode->i_mapping->a_ops = &ext4_da_aops; | |
3602 | else if (ext4_should_order_data(inode)) | |
617ba13b | 3603 | inode->i_mapping->a_ops = &ext4_ordered_aops; |
64769240 AT |
3604 | else if (ext4_should_writeback_data(inode) && |
3605 | test_opt(inode->i_sb, DELALLOC)) | |
3606 | inode->i_mapping->a_ops = &ext4_da_aops; | |
617ba13b MC |
3607 | else if (ext4_should_writeback_data(inode)) |
3608 | inode->i_mapping->a_ops = &ext4_writeback_aops; | |
ac27a0ec | 3609 | else |
617ba13b | 3610 | inode->i_mapping->a_ops = &ext4_journalled_aops; |
ac27a0ec DK |
3611 | } |
3612 | ||
3613 | /* | |
617ba13b | 3614 | * ext4_block_truncate_page() zeroes out a mapping from file offset `from' |
ac27a0ec DK |
3615 | * up to the end of the block which corresponds to `from'. |
3616 | * This required during truncate. We need to physically zero the tail end | |
3617 | * of that block so it doesn't yield old data if the file is later grown. | |
3618 | */ | |
cf108bca | 3619 | int ext4_block_truncate_page(handle_t *handle, |
ac27a0ec DK |
3620 | struct address_space *mapping, loff_t from) |
3621 | { | |
617ba13b | 3622 | ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT; |
ac27a0ec | 3623 | unsigned offset = from & (PAGE_CACHE_SIZE-1); |
725d26d3 AK |
3624 | unsigned blocksize, length, pos; |
3625 | ext4_lblk_t iblock; | |
ac27a0ec DK |
3626 | struct inode *inode = mapping->host; |
3627 | struct buffer_head *bh; | |
cf108bca | 3628 | struct page *page; |
ac27a0ec | 3629 | int err = 0; |
ac27a0ec | 3630 | |
cf108bca JK |
3631 | page = grab_cache_page(mapping, from >> PAGE_CACHE_SHIFT); |
3632 | if (!page) | |
3633 | return -EINVAL; | |
3634 | ||
ac27a0ec DK |
3635 | blocksize = inode->i_sb->s_blocksize; |
3636 | length = blocksize - (offset & (blocksize - 1)); | |
3637 | iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); | |
3638 | ||
3639 | /* | |
3640 | * For "nobh" option, we can only work if we don't need to | |
3641 | * read-in the page - otherwise we create buffers to do the IO. | |
3642 | */ | |
3643 | if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) && | |
617ba13b | 3644 | ext4_should_writeback_data(inode) && PageUptodate(page)) { |
eebd2aa3 | 3645 | zero_user(page, offset, length); |
ac27a0ec DK |
3646 | set_page_dirty(page); |
3647 | goto unlock; | |
3648 | } | |
3649 | ||
3650 | if (!page_has_buffers(page)) | |
3651 | create_empty_buffers(page, blocksize, 0); | |
3652 | ||
3653 | /* Find the buffer that contains "offset" */ | |
3654 | bh = page_buffers(page); | |
3655 | pos = blocksize; | |
3656 | while (offset >= pos) { | |
3657 | bh = bh->b_this_page; | |
3658 | iblock++; | |
3659 | pos += blocksize; | |
3660 | } | |
3661 | ||
3662 | err = 0; | |
3663 | if (buffer_freed(bh)) { | |
3664 | BUFFER_TRACE(bh, "freed: skip"); | |
3665 | goto unlock; | |
3666 | } | |
3667 | ||
3668 | if (!buffer_mapped(bh)) { | |
3669 | BUFFER_TRACE(bh, "unmapped"); | |
617ba13b | 3670 | ext4_get_block(inode, iblock, bh, 0); |
ac27a0ec DK |
3671 | /* unmapped? It's a hole - nothing to do */ |
3672 | if (!buffer_mapped(bh)) { | |
3673 | BUFFER_TRACE(bh, "still unmapped"); | |
3674 | goto unlock; | |
3675 | } | |
3676 | } | |
3677 | ||
3678 | /* Ok, it's mapped. Make sure it's up-to-date */ | |
3679 | if (PageUptodate(page)) | |
3680 | set_buffer_uptodate(bh); | |
3681 | ||
3682 | if (!buffer_uptodate(bh)) { | |
3683 | err = -EIO; | |
3684 | ll_rw_block(READ, 1, &bh); | |
3685 | wait_on_buffer(bh); | |
3686 | /* Uhhuh. Read error. Complain and punt. */ | |
3687 | if (!buffer_uptodate(bh)) | |
3688 | goto unlock; | |
3689 | } | |
3690 | ||
617ba13b | 3691 | if (ext4_should_journal_data(inode)) { |
ac27a0ec | 3692 | BUFFER_TRACE(bh, "get write access"); |
617ba13b | 3693 | err = ext4_journal_get_write_access(handle, bh); |
ac27a0ec DK |
3694 | if (err) |
3695 | goto unlock; | |
3696 | } | |
3697 | ||
eebd2aa3 | 3698 | zero_user(page, offset, length); |
ac27a0ec DK |
3699 | |
3700 | BUFFER_TRACE(bh, "zeroed end of block"); | |
3701 | ||
3702 | err = 0; | |
617ba13b | 3703 | if (ext4_should_journal_data(inode)) { |
0390131b | 3704 | err = ext4_handle_dirty_metadata(handle, inode, bh); |
ac27a0ec | 3705 | } else { |
617ba13b | 3706 | if (ext4_should_order_data(inode)) |
678aaf48 | 3707 | err = ext4_jbd2_file_inode(handle, inode); |
ac27a0ec DK |
3708 | mark_buffer_dirty(bh); |
3709 | } | |
3710 | ||
3711 | unlock: | |
3712 | unlock_page(page); | |
3713 | page_cache_release(page); | |
3714 | return err; | |
3715 | } | |
3716 | ||
3717 | /* | |
3718 | * Probably it should be a library function... search for first non-zero word | |
3719 | * or memcmp with zero_page, whatever is better for particular architecture. | |
3720 | * Linus? | |
3721 | */ | |
3722 | static inline int all_zeroes(__le32 *p, __le32 *q) | |
3723 | { | |
3724 | while (p < q) | |
3725 | if (*p++) | |
3726 | return 0; | |
3727 | return 1; | |
3728 | } | |
3729 | ||
3730 | /** | |
617ba13b | 3731 | * ext4_find_shared - find the indirect blocks for partial truncation. |
ac27a0ec DK |
3732 | * @inode: inode in question |
3733 | * @depth: depth of the affected branch | |
617ba13b | 3734 | * @offsets: offsets of pointers in that branch (see ext4_block_to_path) |
ac27a0ec DK |
3735 | * @chain: place to store the pointers to partial indirect blocks |
3736 | * @top: place to the (detached) top of branch | |
3737 | * | |
617ba13b | 3738 | * This is a helper function used by ext4_truncate(). |
ac27a0ec DK |
3739 | * |
3740 | * When we do truncate() we may have to clean the ends of several | |
3741 | * indirect blocks but leave the blocks themselves alive. Block is | |
3742 | * partially truncated if some data below the new i_size is refered | |
3743 | * from it (and it is on the path to the first completely truncated | |
3744 | * data block, indeed). We have to free the top of that path along | |
3745 | * with everything to the right of the path. Since no allocation | |
617ba13b | 3746 | * past the truncation point is possible until ext4_truncate() |
ac27a0ec DK |
3747 | * finishes, we may safely do the latter, but top of branch may |
3748 | * require special attention - pageout below the truncation point | |
3749 | * might try to populate it. | |
3750 | * | |
3751 | * We atomically detach the top of branch from the tree, store the | |
3752 | * block number of its root in *@top, pointers to buffer_heads of | |
3753 | * partially truncated blocks - in @chain[].bh and pointers to | |
3754 | * their last elements that should not be removed - in | |
3755 | * @chain[].p. Return value is the pointer to last filled element | |
3756 | * of @chain. | |
3757 | * | |
3758 | * The work left to caller to do the actual freeing of subtrees: | |
3759 | * a) free the subtree starting from *@top | |
3760 | * b) free the subtrees whose roots are stored in | |
3761 | * (@chain[i].p+1 .. end of @chain[i].bh->b_data) | |
3762 | * c) free the subtrees growing from the inode past the @chain[0]. | |
3763 | * (no partially truncated stuff there). */ | |
3764 | ||
617ba13b | 3765 | static Indirect *ext4_find_shared(struct inode *inode, int depth, |
725d26d3 | 3766 | ext4_lblk_t offsets[4], Indirect chain[4], __le32 *top) |
ac27a0ec DK |
3767 | { |
3768 | Indirect *partial, *p; | |
3769 | int k, err; | |
3770 | ||
3771 | *top = 0; | |
3772 | /* Make k index the deepest non-null offest + 1 */ | |
3773 | for (k = depth; k > 1 && !offsets[k-1]; k--) | |
3774 | ; | |
617ba13b | 3775 | partial = ext4_get_branch(inode, k, offsets, chain, &err); |
ac27a0ec DK |
3776 | /* Writer: pointers */ |
3777 | if (!partial) | |
3778 | partial = chain + k-1; | |
3779 | /* | |
3780 | * If the branch acquired continuation since we've looked at it - | |
3781 | * fine, it should all survive and (new) top doesn't belong to us. | |
3782 | */ | |
3783 | if (!partial->key && *partial->p) | |
3784 | /* Writer: end */ | |
3785 | goto no_top; | |
af5bc92d | 3786 | for (p = partial; (p > chain) && all_zeroes((__le32 *) p->bh->b_data, p->p); p--) |
ac27a0ec DK |
3787 | ; |
3788 | /* | |
3789 | * OK, we've found the last block that must survive. The rest of our | |
3790 | * branch should be detached before unlocking. However, if that rest | |
3791 | * of branch is all ours and does not grow immediately from the inode | |
3792 | * it's easier to cheat and just decrement partial->p. | |
3793 | */ | |
3794 | if (p == chain + k - 1 && p > chain) { | |
3795 | p->p--; | |
3796 | } else { | |
3797 | *top = *p->p; | |
617ba13b | 3798 | /* Nope, don't do this in ext4. Must leave the tree intact */ |
ac27a0ec DK |
3799 | #if 0 |
3800 | *p->p = 0; | |
3801 | #endif | |
3802 | } | |
3803 | /* Writer: end */ | |
3804 | ||
af5bc92d | 3805 | while (partial > p) { |
ac27a0ec DK |
3806 | brelse(partial->bh); |
3807 | partial--; | |
3808 | } | |
3809 | no_top: | |
3810 | return partial; | |
3811 | } | |
3812 | ||
3813 | /* | |
3814 | * Zero a number of block pointers in either an inode or an indirect block. | |
3815 | * If we restart the transaction we must again get write access to the | |
3816 | * indirect block for further modification. | |
3817 | * | |
3818 | * We release `count' blocks on disk, but (last - first) may be greater | |
3819 | * than `count' because there can be holes in there. | |
3820 | */ | |
617ba13b MC |
3821 | static void ext4_clear_blocks(handle_t *handle, struct inode *inode, |
3822 | struct buffer_head *bh, ext4_fsblk_t block_to_free, | |
ac27a0ec DK |
3823 | unsigned long count, __le32 *first, __le32 *last) |
3824 | { | |
3825 | __le32 *p; | |
3826 | if (try_to_extend_transaction(handle, inode)) { | |
3827 | if (bh) { | |
0390131b FM |
3828 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
3829 | ext4_handle_dirty_metadata(handle, inode, bh); | |
ac27a0ec | 3830 | } |
617ba13b MC |
3831 | ext4_mark_inode_dirty(handle, inode); |
3832 | ext4_journal_test_restart(handle, inode); | |
ac27a0ec DK |
3833 | if (bh) { |
3834 | BUFFER_TRACE(bh, "retaking write access"); | |
617ba13b | 3835 | ext4_journal_get_write_access(handle, bh); |
ac27a0ec DK |
3836 | } |
3837 | } | |
3838 | ||
3839 | /* | |
3840 | * Any buffers which are on the journal will be in memory. We find | |
dab291af | 3841 | * them on the hash table so jbd2_journal_revoke() will run jbd2_journal_forget() |
ac27a0ec | 3842 | * on them. We've already detached each block from the file, so |
dab291af | 3843 | * bforget() in jbd2_journal_forget() should be safe. |
ac27a0ec | 3844 | * |
dab291af | 3845 | * AKPM: turn on bforget in jbd2_journal_forget()!!! |
ac27a0ec DK |
3846 | */ |
3847 | for (p = first; p < last; p++) { | |
3848 | u32 nr = le32_to_cpu(*p); | |
3849 | if (nr) { | |
1d03ec98 | 3850 | struct buffer_head *tbh; |
ac27a0ec DK |
3851 | |
3852 | *p = 0; | |
1d03ec98 AK |
3853 | tbh = sb_find_get_block(inode->i_sb, nr); |
3854 | ext4_forget(handle, 0, inode, tbh, nr); | |
ac27a0ec DK |
3855 | } |
3856 | } | |
3857 | ||
c9de560d | 3858 | ext4_free_blocks(handle, inode, block_to_free, count, 0); |
ac27a0ec DK |
3859 | } |
3860 | ||
3861 | /** | |
617ba13b | 3862 | * ext4_free_data - free a list of data blocks |
ac27a0ec DK |
3863 | * @handle: handle for this transaction |
3864 | * @inode: inode we are dealing with | |
3865 | * @this_bh: indirect buffer_head which contains *@first and *@last | |
3866 | * @first: array of block numbers | |
3867 | * @last: points immediately past the end of array | |
3868 | * | |
3869 | * We are freeing all blocks refered from that array (numbers are stored as | |
3870 | * little-endian 32-bit) and updating @inode->i_blocks appropriately. | |
3871 | * | |
3872 | * We accumulate contiguous runs of blocks to free. Conveniently, if these | |
3873 | * blocks are contiguous then releasing them at one time will only affect one | |
3874 | * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't | |
3875 | * actually use a lot of journal space. | |
3876 | * | |
3877 | * @this_bh will be %NULL if @first and @last point into the inode's direct | |
3878 | * block pointers. | |
3879 | */ | |
617ba13b | 3880 | static void ext4_free_data(handle_t *handle, struct inode *inode, |
ac27a0ec DK |
3881 | struct buffer_head *this_bh, |
3882 | __le32 *first, __le32 *last) | |
3883 | { | |
617ba13b | 3884 | ext4_fsblk_t block_to_free = 0; /* Starting block # of a run */ |
ac27a0ec DK |
3885 | unsigned long count = 0; /* Number of blocks in the run */ |
3886 | __le32 *block_to_free_p = NULL; /* Pointer into inode/ind | |
3887 | corresponding to | |
3888 | block_to_free */ | |
617ba13b | 3889 | ext4_fsblk_t nr; /* Current block # */ |
ac27a0ec DK |
3890 | __le32 *p; /* Pointer into inode/ind |
3891 | for current block */ | |
3892 | int err; | |
3893 | ||
3894 | if (this_bh) { /* For indirect block */ | |
3895 | BUFFER_TRACE(this_bh, "get_write_access"); | |
617ba13b | 3896 | err = ext4_journal_get_write_access(handle, this_bh); |
ac27a0ec DK |
3897 | /* Important: if we can't update the indirect pointers |
3898 | * to the blocks, we can't free them. */ | |
3899 | if (err) | |
3900 | return; | |
3901 | } | |
3902 | ||
3903 | for (p = first; p < last; p++) { | |
3904 | nr = le32_to_cpu(*p); | |
3905 | if (nr) { | |
3906 | /* accumulate blocks to free if they're contiguous */ | |
3907 | if (count == 0) { | |
3908 | block_to_free = nr; | |
3909 | block_to_free_p = p; | |
3910 | count = 1; | |
3911 | } else if (nr == block_to_free + count) { | |
3912 | count++; | |
3913 | } else { | |
617ba13b | 3914 | ext4_clear_blocks(handle, inode, this_bh, |
ac27a0ec DK |
3915 | block_to_free, |
3916 | count, block_to_free_p, p); | |
3917 | block_to_free = nr; | |
3918 | block_to_free_p = p; | |
3919 | count = 1; | |
3920 | } | |
3921 | } | |
3922 | } | |
3923 | ||
3924 | if (count > 0) | |
617ba13b | 3925 | ext4_clear_blocks(handle, inode, this_bh, block_to_free, |
ac27a0ec DK |
3926 | count, block_to_free_p, p); |
3927 | ||
3928 | if (this_bh) { | |
0390131b | 3929 | BUFFER_TRACE(this_bh, "call ext4_handle_dirty_metadata"); |
71dc8fbc DG |
3930 | |
3931 | /* | |
3932 | * The buffer head should have an attached journal head at this | |
3933 | * point. However, if the data is corrupted and an indirect | |
3934 | * block pointed to itself, it would have been detached when | |
3935 | * the block was cleared. Check for this instead of OOPSing. | |
3936 | */ | |
e7f07968 | 3937 | if ((EXT4_JOURNAL(inode) == NULL) || bh2jh(this_bh)) |
0390131b | 3938 | ext4_handle_dirty_metadata(handle, inode, this_bh); |
71dc8fbc DG |
3939 | else |
3940 | ext4_error(inode->i_sb, __func__, | |
3941 | "circular indirect block detected, " | |
3942 | "inode=%lu, block=%llu", | |
3943 | inode->i_ino, | |
3944 | (unsigned long long) this_bh->b_blocknr); | |
ac27a0ec DK |
3945 | } |
3946 | } | |
3947 | ||
3948 | /** | |
617ba13b | 3949 | * ext4_free_branches - free an array of branches |
ac27a0ec DK |
3950 | * @handle: JBD handle for this transaction |
3951 | * @inode: inode we are dealing with | |
3952 | * @parent_bh: the buffer_head which contains *@first and *@last | |
3953 | * @first: array of block numbers | |
3954 | * @last: pointer immediately past the end of array | |
3955 | * @depth: depth of the branches to free | |
3956 | * | |
3957 | * We are freeing all blocks refered from these branches (numbers are | |
3958 | * stored as little-endian 32-bit) and updating @inode->i_blocks | |
3959 | * appropriately. | |
3960 | */ | |
617ba13b | 3961 | static void ext4_free_branches(handle_t *handle, struct inode *inode, |
ac27a0ec DK |
3962 | struct buffer_head *parent_bh, |
3963 | __le32 *first, __le32 *last, int depth) | |
3964 | { | |
617ba13b | 3965 | ext4_fsblk_t nr; |
ac27a0ec DK |
3966 | __le32 *p; |
3967 | ||
0390131b | 3968 | if (ext4_handle_is_aborted(handle)) |
ac27a0ec DK |
3969 | return; |
3970 | ||
3971 | if (depth--) { | |
3972 | struct buffer_head *bh; | |
617ba13b | 3973 | int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
ac27a0ec DK |
3974 | p = last; |
3975 | while (--p >= first) { | |
3976 | nr = le32_to_cpu(*p); | |
3977 | if (!nr) | |
3978 | continue; /* A hole */ | |
3979 | ||
3980 | /* Go read the buffer for the next level down */ | |
3981 | bh = sb_bread(inode->i_sb, nr); | |
3982 | ||
3983 | /* | |
3984 | * A read failure? Report error and clear slot | |
3985 | * (should be rare). | |
3986 | */ | |
3987 | if (!bh) { | |
617ba13b | 3988 | ext4_error(inode->i_sb, "ext4_free_branches", |
2ae02107 | 3989 | "Read failure, inode=%lu, block=%llu", |
ac27a0ec DK |
3990 | inode->i_ino, nr); |
3991 | continue; | |
3992 | } | |
3993 | ||
3994 | /* This zaps the entire block. Bottom up. */ | |
3995 | BUFFER_TRACE(bh, "free child branches"); | |
617ba13b | 3996 | ext4_free_branches(handle, inode, bh, |
af5bc92d TT |
3997 | (__le32 *) bh->b_data, |
3998 | (__le32 *) bh->b_data + addr_per_block, | |
3999 | depth); | |
ac27a0ec DK |
4000 | |
4001 | /* | |
4002 | * We've probably journalled the indirect block several | |
4003 | * times during the truncate. But it's no longer | |
4004 | * needed and we now drop it from the transaction via | |
dab291af | 4005 | * jbd2_journal_revoke(). |
ac27a0ec DK |
4006 | * |
4007 | * That's easy if it's exclusively part of this | |
4008 | * transaction. But if it's part of the committing | |
dab291af | 4009 | * transaction then jbd2_journal_forget() will simply |
ac27a0ec | 4010 | * brelse() it. That means that if the underlying |
617ba13b | 4011 | * block is reallocated in ext4_get_block(), |
ac27a0ec DK |
4012 | * unmap_underlying_metadata() will find this block |
4013 | * and will try to get rid of it. damn, damn. | |
4014 | * | |
4015 | * If this block has already been committed to the | |
4016 | * journal, a revoke record will be written. And | |
4017 | * revoke records must be emitted *before* clearing | |
4018 | * this block's bit in the bitmaps. | |
4019 | */ | |
617ba13b | 4020 | ext4_forget(handle, 1, inode, bh, bh->b_blocknr); |
ac27a0ec DK |
4021 | |
4022 | /* | |
4023 | * Everything below this this pointer has been | |
4024 | * released. Now let this top-of-subtree go. | |
4025 | * | |
4026 | * We want the freeing of this indirect block to be | |
4027 | * atomic in the journal with the updating of the | |
4028 | * bitmap block which owns it. So make some room in | |
4029 | * the journal. | |
4030 | * | |
4031 | * We zero the parent pointer *after* freeing its | |
4032 | * pointee in the bitmaps, so if extend_transaction() | |
4033 | * for some reason fails to put the bitmap changes and | |
4034 | * the release into the same transaction, recovery | |
4035 | * will merely complain about releasing a free block, | |
4036 | * rather than leaking blocks. | |
4037 | */ | |
0390131b | 4038 | if (ext4_handle_is_aborted(handle)) |
ac27a0ec DK |
4039 | return; |
4040 | if (try_to_extend_transaction(handle, inode)) { | |
617ba13b MC |
4041 | ext4_mark_inode_dirty(handle, inode); |
4042 | ext4_journal_test_restart(handle, inode); | |
ac27a0ec DK |
4043 | } |
4044 | ||
c9de560d | 4045 | ext4_free_blocks(handle, inode, nr, 1, 1); |
ac27a0ec DK |
4046 | |
4047 | if (parent_bh) { | |
4048 | /* | |
4049 | * The block which we have just freed is | |
4050 | * pointed to by an indirect block: journal it | |
4051 | */ | |
4052 | BUFFER_TRACE(parent_bh, "get_write_access"); | |
617ba13b | 4053 | if (!ext4_journal_get_write_access(handle, |
ac27a0ec DK |
4054 | parent_bh)){ |
4055 | *p = 0; | |
4056 | BUFFER_TRACE(parent_bh, | |
0390131b FM |
4057 | "call ext4_handle_dirty_metadata"); |
4058 | ext4_handle_dirty_metadata(handle, | |
4059 | inode, | |
4060 | parent_bh); | |
ac27a0ec DK |
4061 | } |
4062 | } | |
4063 | } | |
4064 | } else { | |
4065 | /* We have reached the bottom of the tree. */ | |
4066 | BUFFER_TRACE(parent_bh, "free data blocks"); | |
617ba13b | 4067 | ext4_free_data(handle, inode, parent_bh, first, last); |
ac27a0ec DK |
4068 | } |
4069 | } | |
4070 | ||
91ef4caf DG |
4071 | int ext4_can_truncate(struct inode *inode) |
4072 | { | |
4073 | if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) | |
4074 | return 0; | |
4075 | if (S_ISREG(inode->i_mode)) | |
4076 | return 1; | |
4077 | if (S_ISDIR(inode->i_mode)) | |
4078 | return 1; | |
4079 | if (S_ISLNK(inode->i_mode)) | |
4080 | return !ext4_inode_is_fast_symlink(inode); | |
4081 | return 0; | |
4082 | } | |
4083 | ||
ac27a0ec | 4084 | /* |
617ba13b | 4085 | * ext4_truncate() |
ac27a0ec | 4086 | * |
617ba13b MC |
4087 | * We block out ext4_get_block() block instantiations across the entire |
4088 | * transaction, and VFS/VM ensures that ext4_truncate() cannot run | |
ac27a0ec DK |
4089 | * simultaneously on behalf of the same inode. |
4090 | * | |
4091 | * As we work through the truncate and commmit bits of it to the journal there | |
4092 | * is one core, guiding principle: the file's tree must always be consistent on | |
4093 | * disk. We must be able to restart the truncate after a crash. | |
4094 | * | |
4095 | * The file's tree may be transiently inconsistent in memory (although it | |
4096 | * probably isn't), but whenever we close off and commit a journal transaction, | |
4097 | * the contents of (the filesystem + the journal) must be consistent and | |
4098 | * restartable. It's pretty simple, really: bottom up, right to left (although | |
4099 | * left-to-right works OK too). | |
4100 | * | |
4101 | * Note that at recovery time, journal replay occurs *before* the restart of | |
4102 | * truncate against the orphan inode list. | |
4103 | * | |
4104 | * The committed inode has the new, desired i_size (which is the same as | |
617ba13b | 4105 | * i_disksize in this case). After a crash, ext4_orphan_cleanup() will see |
ac27a0ec | 4106 | * that this inode's truncate did not complete and it will again call |
617ba13b MC |
4107 | * ext4_truncate() to have another go. So there will be instantiated blocks |
4108 | * to the right of the truncation point in a crashed ext4 filesystem. But | |
ac27a0ec | 4109 | * that's fine - as long as they are linked from the inode, the post-crash |
617ba13b | 4110 | * ext4_truncate() run will find them and release them. |
ac27a0ec | 4111 | */ |
617ba13b | 4112 | void ext4_truncate(struct inode *inode) |
ac27a0ec DK |
4113 | { |
4114 | handle_t *handle; | |
617ba13b | 4115 | struct ext4_inode_info *ei = EXT4_I(inode); |
ac27a0ec | 4116 | __le32 *i_data = ei->i_data; |
617ba13b | 4117 | int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb); |
ac27a0ec | 4118 | struct address_space *mapping = inode->i_mapping; |
725d26d3 | 4119 | ext4_lblk_t offsets[4]; |
ac27a0ec DK |
4120 | Indirect chain[4]; |
4121 | Indirect *partial; | |
4122 | __le32 nr = 0; | |
4123 | int n; | |
725d26d3 | 4124 | ext4_lblk_t last_block; |
ac27a0ec | 4125 | unsigned blocksize = inode->i_sb->s_blocksize; |
ac27a0ec | 4126 | |
91ef4caf | 4127 | if (!ext4_can_truncate(inode)) |
ac27a0ec DK |
4128 | return; |
4129 | ||
0eab9282 TT |
4130 | if (ei->i_disksize && inode->i_size == 0 && |
4131 | !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC)) | |
7d8f9f7d TT |
4132 | ei->i_state |= EXT4_STATE_DA_ALLOC_CLOSE; |
4133 | ||
1d03ec98 | 4134 | if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) { |
cf108bca | 4135 | ext4_ext_truncate(inode); |
1d03ec98 AK |
4136 | return; |
4137 | } | |
a86c6181 | 4138 | |
ac27a0ec | 4139 | handle = start_transaction(inode); |
cf108bca | 4140 | if (IS_ERR(handle)) |
ac27a0ec | 4141 | return; /* AKPM: return what? */ |
ac27a0ec DK |
4142 | |
4143 | last_block = (inode->i_size + blocksize-1) | |
617ba13b | 4144 | >> EXT4_BLOCK_SIZE_BITS(inode->i_sb); |
ac27a0ec | 4145 | |
cf108bca JK |
4146 | if (inode->i_size & (blocksize - 1)) |
4147 | if (ext4_block_truncate_page(handle, mapping, inode->i_size)) | |
4148 | goto out_stop; | |
ac27a0ec | 4149 | |
617ba13b | 4150 | n = ext4_block_to_path(inode, last_block, offsets, NULL); |
ac27a0ec DK |
4151 | if (n == 0) |
4152 | goto out_stop; /* error */ | |
4153 | ||
4154 | /* | |
4155 | * OK. This truncate is going to happen. We add the inode to the | |
4156 | * orphan list, so that if this truncate spans multiple transactions, | |
4157 | * and we crash, we will resume the truncate when the filesystem | |
4158 | * recovers. It also marks the inode dirty, to catch the new size. | |
4159 | * | |
4160 | * Implication: the file must always be in a sane, consistent | |
4161 | * truncatable state while each transaction commits. | |
4162 | */ | |
617ba13b | 4163 | if (ext4_orphan_add(handle, inode)) |
ac27a0ec DK |
4164 | goto out_stop; |
4165 | ||
632eaeab MC |
4166 | /* |
4167 | * From here we block out all ext4_get_block() callers who want to | |
4168 | * modify the block allocation tree. | |
4169 | */ | |
4170 | down_write(&ei->i_data_sem); | |
b4df2030 | 4171 | |
c2ea3fde | 4172 | ext4_discard_preallocations(inode); |
b4df2030 | 4173 | |
ac27a0ec DK |
4174 | /* |
4175 | * The orphan list entry will now protect us from any crash which | |
4176 | * occurs before the truncate completes, so it is now safe to propagate | |
4177 | * the new, shorter inode size (held for now in i_size) into the | |
4178 | * on-disk inode. We do this via i_disksize, which is the value which | |
617ba13b | 4179 | * ext4 *really* writes onto the disk inode. |
ac27a0ec DK |
4180 | */ |
4181 | ei->i_disksize = inode->i_size; | |
4182 | ||
ac27a0ec | 4183 | if (n == 1) { /* direct blocks */ |
617ba13b MC |
4184 | ext4_free_data(handle, inode, NULL, i_data+offsets[0], |
4185 | i_data + EXT4_NDIR_BLOCKS); | |
ac27a0ec DK |
4186 | goto do_indirects; |
4187 | } | |
4188 | ||
617ba13b | 4189 | partial = ext4_find_shared(inode, n, offsets, chain, &nr); |
ac27a0ec DK |
4190 | /* Kill the top of shared branch (not detached) */ |
4191 | if (nr) { | |
4192 | if (partial == chain) { | |
4193 | /* Shared branch grows from the inode */ | |
617ba13b | 4194 | ext4_free_branches(handle, inode, NULL, |
ac27a0ec DK |
4195 | &nr, &nr+1, (chain+n-1) - partial); |
4196 | *partial->p = 0; | |
4197 | /* | |
4198 | * We mark the inode dirty prior to restart, | |
4199 | * and prior to stop. No need for it here. | |
4200 | */ | |
4201 | } else { | |
4202 | /* Shared branch grows from an indirect block */ | |
4203 | BUFFER_TRACE(partial->bh, "get_write_access"); | |
617ba13b | 4204 | ext4_free_branches(handle, inode, partial->bh, |
ac27a0ec DK |
4205 | partial->p, |
4206 | partial->p+1, (chain+n-1) - partial); | |
4207 | } | |
4208 | } | |
4209 | /* Clear the ends of indirect blocks on the shared branch */ | |
4210 | while (partial > chain) { | |
617ba13b | 4211 | ext4_free_branches(handle, inode, partial->bh, partial->p + 1, |
ac27a0ec DK |
4212 | (__le32*)partial->bh->b_data+addr_per_block, |
4213 | (chain+n-1) - partial); | |
4214 | BUFFER_TRACE(partial->bh, "call brelse"); | |
4215 | brelse (partial->bh); | |
4216 | partial--; | |
4217 | } | |
4218 | do_indirects: | |
4219 | /* Kill the remaining (whole) subtrees */ | |
4220 | switch (offsets[0]) { | |
4221 | default: | |
617ba13b | 4222 | nr = i_data[EXT4_IND_BLOCK]; |
ac27a0ec | 4223 | if (nr) { |
617ba13b MC |
4224 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 1); |
4225 | i_data[EXT4_IND_BLOCK] = 0; | |
ac27a0ec | 4226 | } |
617ba13b MC |
4227 | case EXT4_IND_BLOCK: |
4228 | nr = i_data[EXT4_DIND_BLOCK]; | |
ac27a0ec | 4229 | if (nr) { |
617ba13b MC |
4230 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 2); |
4231 | i_data[EXT4_DIND_BLOCK] = 0; | |
ac27a0ec | 4232 | } |
617ba13b MC |
4233 | case EXT4_DIND_BLOCK: |
4234 | nr = i_data[EXT4_TIND_BLOCK]; | |
ac27a0ec | 4235 | if (nr) { |
617ba13b MC |
4236 | ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 3); |
4237 | i_data[EXT4_TIND_BLOCK] = 0; | |
ac27a0ec | 4238 | } |
617ba13b | 4239 | case EXT4_TIND_BLOCK: |
ac27a0ec DK |
4240 | ; |
4241 | } | |
4242 | ||
0e855ac8 | 4243 | up_write(&ei->i_data_sem); |
ef7f3835 | 4244 | inode->i_mtime = inode->i_ctime = ext4_current_time(inode); |
617ba13b | 4245 | ext4_mark_inode_dirty(handle, inode); |
ac27a0ec DK |
4246 | |
4247 | /* | |
4248 | * In a multi-transaction truncate, we only make the final transaction | |
4249 | * synchronous | |
4250 | */ | |
4251 | if (IS_SYNC(inode)) | |
0390131b | 4252 | ext4_handle_sync(handle); |
ac27a0ec DK |
4253 | out_stop: |
4254 | /* | |
4255 | * If this was a simple ftruncate(), and the file will remain alive | |
4256 | * then we need to clear up the orphan record which we created above. | |
4257 | * However, if this was a real unlink then we were called by | |
617ba13b | 4258 | * ext4_delete_inode(), and we allow that function to clean up the |
ac27a0ec DK |
4259 | * orphan info for us. |
4260 | */ | |
4261 | if (inode->i_nlink) | |
617ba13b | 4262 | ext4_orphan_del(handle, inode); |
ac27a0ec | 4263 | |
617ba13b | 4264 | ext4_journal_stop(handle); |
ac27a0ec DK |
4265 | } |
4266 | ||
ac27a0ec | 4267 | /* |
617ba13b | 4268 | * ext4_get_inode_loc returns with an extra refcount against the inode's |
ac27a0ec DK |
4269 | * underlying buffer_head on success. If 'in_mem' is true, we have all |
4270 | * data in memory that is needed to recreate the on-disk version of this | |
4271 | * inode. | |
4272 | */ | |
617ba13b MC |
4273 | static int __ext4_get_inode_loc(struct inode *inode, |
4274 | struct ext4_iloc *iloc, int in_mem) | |
ac27a0ec | 4275 | { |
240799cd TT |
4276 | struct ext4_group_desc *gdp; |
4277 | struct buffer_head *bh; | |
4278 | struct super_block *sb = inode->i_sb; | |
4279 | ext4_fsblk_t block; | |
4280 | int inodes_per_block, inode_offset; | |
4281 | ||
3a06d778 | 4282 | iloc->bh = NULL; |
240799cd TT |
4283 | if (!ext4_valid_inum(sb, inode->i_ino)) |
4284 | return -EIO; | |
ac27a0ec | 4285 | |
240799cd TT |
4286 | iloc->block_group = (inode->i_ino - 1) / EXT4_INODES_PER_GROUP(sb); |
4287 | gdp = ext4_get_group_desc(sb, iloc->block_group, NULL); | |
4288 | if (!gdp) | |
ac27a0ec DK |
4289 | return -EIO; |
4290 | ||
240799cd TT |
4291 | /* |
4292 | * Figure out the offset within the block group inode table | |
4293 | */ | |
4294 | inodes_per_block = (EXT4_BLOCK_SIZE(sb) / EXT4_INODE_SIZE(sb)); | |
4295 | inode_offset = ((inode->i_ino - 1) % | |
4296 | EXT4_INODES_PER_GROUP(sb)); | |
4297 | block = ext4_inode_table(sb, gdp) + (inode_offset / inodes_per_block); | |
4298 | iloc->offset = (inode_offset % inodes_per_block) * EXT4_INODE_SIZE(sb); | |
4299 | ||
4300 | bh = sb_getblk(sb, block); | |
ac27a0ec | 4301 | if (!bh) { |
240799cd TT |
4302 | ext4_error(sb, "ext4_get_inode_loc", "unable to read " |
4303 | "inode block - inode=%lu, block=%llu", | |
4304 | inode->i_ino, block); | |
ac27a0ec DK |
4305 | return -EIO; |
4306 | } | |
4307 | if (!buffer_uptodate(bh)) { | |
4308 | lock_buffer(bh); | |
9c83a923 HK |
4309 | |
4310 | /* | |
4311 | * If the buffer has the write error flag, we have failed | |
4312 | * to write out another inode in the same block. In this | |
4313 | * case, we don't have to read the block because we may | |
4314 | * read the old inode data successfully. | |
4315 | */ | |
4316 | if (buffer_write_io_error(bh) && !buffer_uptodate(bh)) | |
4317 | set_buffer_uptodate(bh); | |
4318 | ||
ac27a0ec DK |
4319 | if (buffer_uptodate(bh)) { |
4320 | /* someone brought it uptodate while we waited */ | |
4321 | unlock_buffer(bh); | |
4322 | goto has_buffer; | |
4323 | } | |
4324 | ||
4325 | /* | |
4326 | * If we have all information of the inode in memory and this | |
4327 | * is the only valid inode in the block, we need not read the | |
4328 | * block. | |
4329 | */ | |
4330 | if (in_mem) { | |
4331 | struct buffer_head *bitmap_bh; | |
240799cd | 4332 | int i, start; |
ac27a0ec | 4333 | |
240799cd | 4334 | start = inode_offset & ~(inodes_per_block - 1); |
ac27a0ec | 4335 | |
240799cd TT |
4336 | /* Is the inode bitmap in cache? */ |
4337 | bitmap_bh = sb_getblk(sb, ext4_inode_bitmap(sb, gdp)); | |
ac27a0ec DK |
4338 | if (!bitmap_bh) |
4339 | goto make_io; | |
4340 | ||
4341 | /* | |
4342 | * If the inode bitmap isn't in cache then the | |
4343 | * optimisation may end up performing two reads instead | |
4344 | * of one, so skip it. | |
4345 | */ | |
4346 | if (!buffer_uptodate(bitmap_bh)) { | |
4347 | brelse(bitmap_bh); | |
4348 | goto make_io; | |
4349 | } | |
240799cd | 4350 | for (i = start; i < start + inodes_per_block; i++) { |
ac27a0ec DK |
4351 | if (i == inode_offset) |
4352 | continue; | |
617ba13b | 4353 | if (ext4_test_bit(i, bitmap_bh->b_data)) |
ac27a0ec DK |
4354 | break; |
4355 | } | |
4356 | brelse(bitmap_bh); | |
240799cd | 4357 | if (i == start + inodes_per_block) { |
ac27a0ec DK |
4358 | /* all other inodes are free, so skip I/O */ |
4359 | memset(bh->b_data, 0, bh->b_size); | |
4360 | set_buffer_uptodate(bh); | |
4361 | unlock_buffer(bh); | |
4362 | goto has_buffer; | |
4363 | } | |
4364 | } | |
4365 | ||
4366 | make_io: | |
240799cd TT |
4367 | /* |
4368 | * If we need to do any I/O, try to pre-readahead extra | |
4369 | * blocks from the inode table. | |
4370 | */ | |
4371 | if (EXT4_SB(sb)->s_inode_readahead_blks) { | |
4372 | ext4_fsblk_t b, end, table; | |
4373 | unsigned num; | |
4374 | ||
4375 | table = ext4_inode_table(sb, gdp); | |
b713a5ec | 4376 | /* s_inode_readahead_blks is always a power of 2 */ |
240799cd TT |
4377 | b = block & ~(EXT4_SB(sb)->s_inode_readahead_blks-1); |
4378 | if (table > b) | |
4379 | b = table; | |
4380 | end = b + EXT4_SB(sb)->s_inode_readahead_blks; | |
4381 | num = EXT4_INODES_PER_GROUP(sb); | |
4382 | if (EXT4_HAS_RO_COMPAT_FEATURE(sb, | |
4383 | EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) | |
560671a0 | 4384 | num -= ext4_itable_unused_count(sb, gdp); |
240799cd TT |
4385 | table += num / inodes_per_block; |
4386 | if (end > table) | |
4387 | end = table; | |
4388 | while (b <= end) | |
4389 | sb_breadahead(sb, b++); | |
4390 | } | |
4391 | ||
ac27a0ec DK |
4392 | /* |
4393 | * There are other valid inodes in the buffer, this inode | |
4394 | * has in-inode xattrs, or we don't have this inode in memory. | |
4395 | * Read the block from disk. | |
4396 | */ | |
4397 | get_bh(bh); | |
4398 | bh->b_end_io = end_buffer_read_sync; | |
4399 | submit_bh(READ_META, bh); | |
4400 | wait_on_buffer(bh); | |
4401 | if (!buffer_uptodate(bh)) { | |
240799cd TT |
4402 | ext4_error(sb, __func__, |
4403 | "unable to read inode block - inode=%lu, " | |
4404 | "block=%llu", inode->i_ino, block); | |
ac27a0ec DK |
4405 | brelse(bh); |
4406 | return -EIO; | |
4407 | } | |
4408 | } | |
4409 | has_buffer: | |
4410 | iloc->bh = bh; | |
4411 | return 0; | |
4412 | } | |
4413 | ||
617ba13b | 4414 | int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc) |
ac27a0ec DK |
4415 | { |
4416 | /* We have all inode data except xattrs in memory here. */ | |
617ba13b MC |
4417 | return __ext4_get_inode_loc(inode, iloc, |
4418 | !(EXT4_I(inode)->i_state & EXT4_STATE_XATTR)); | |
ac27a0ec DK |
4419 | } |
4420 | ||
617ba13b | 4421 | void ext4_set_inode_flags(struct inode *inode) |
ac27a0ec | 4422 | { |
617ba13b | 4423 | unsigned int flags = EXT4_I(inode)->i_flags; |
ac27a0ec DK |
4424 | |
4425 | inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); | |
617ba13b | 4426 | if (flags & EXT4_SYNC_FL) |
ac27a0ec | 4427 | inode->i_flags |= S_SYNC; |
617ba13b | 4428 | if (flags & EXT4_APPEND_FL) |
ac27a0ec | 4429 | inode->i_flags |= S_APPEND; |
617ba13b | 4430 | if (flags & EXT4_IMMUTABLE_FL) |
ac27a0ec | 4431 | inode->i_flags |= S_IMMUTABLE; |
617ba13b | 4432 | if (flags & EXT4_NOATIME_FL) |
ac27a0ec | 4433 | inode->i_flags |= S_NOATIME; |
617ba13b | 4434 | if (flags & EXT4_DIRSYNC_FL) |
ac27a0ec DK |
4435 | inode->i_flags |= S_DIRSYNC; |
4436 | } | |
4437 | ||
ff9ddf7e JK |
4438 | /* Propagate flags from i_flags to EXT4_I(inode)->i_flags */ |
4439 | void ext4_get_inode_flags(struct ext4_inode_info *ei) | |
4440 | { | |
4441 | unsigned int flags = ei->vfs_inode.i_flags; | |
4442 | ||
4443 | ei->i_flags &= ~(EXT4_SYNC_FL|EXT4_APPEND_FL| | |
4444 | EXT4_IMMUTABLE_FL|EXT4_NOATIME_FL|EXT4_DIRSYNC_FL); | |
4445 | if (flags & S_SYNC) | |
4446 | ei->i_flags |= EXT4_SYNC_FL; | |
4447 | if (flags & S_APPEND) | |
4448 | ei->i_flags |= EXT4_APPEND_FL; | |
4449 | if (flags & S_IMMUTABLE) | |
4450 | ei->i_flags |= EXT4_IMMUTABLE_FL; | |
4451 | if (flags & S_NOATIME) | |
4452 | ei->i_flags |= EXT4_NOATIME_FL; | |
4453 | if (flags & S_DIRSYNC) | |
4454 | ei->i_flags |= EXT4_DIRSYNC_FL; | |
4455 | } | |
0fc1b451 AK |
4456 | static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode, |
4457 | struct ext4_inode_info *ei) | |
4458 | { | |
4459 | blkcnt_t i_blocks ; | |
8180a562 AK |
4460 | struct inode *inode = &(ei->vfs_inode); |
4461 | struct super_block *sb = inode->i_sb; | |
0fc1b451 AK |
4462 | |
4463 | if (EXT4_HAS_RO_COMPAT_FEATURE(sb, | |
4464 | EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) { | |
4465 | /* we are using combined 48 bit field */ | |
4466 | i_blocks = ((u64)le16_to_cpu(raw_inode->i_blocks_high)) << 32 | | |
4467 | le32_to_cpu(raw_inode->i_blocks_lo); | |
8180a562 AK |
4468 | if (ei->i_flags & EXT4_HUGE_FILE_FL) { |
4469 | /* i_blocks represent file system block size */ | |
4470 | return i_blocks << (inode->i_blkbits - 9); | |
4471 | } else { | |
4472 | return i_blocks; | |
4473 | } | |
0fc1b451 AK |
4474 | } else { |
4475 | return le32_to_cpu(raw_inode->i_blocks_lo); | |
4476 | } | |
4477 | } | |
ff9ddf7e | 4478 | |
1d1fe1ee | 4479 | struct inode *ext4_iget(struct super_block *sb, unsigned long ino) |
ac27a0ec | 4480 | { |
617ba13b MC |
4481 | struct ext4_iloc iloc; |
4482 | struct ext4_inode *raw_inode; | |
1d1fe1ee | 4483 | struct ext4_inode_info *ei; |
ac27a0ec | 4484 | struct buffer_head *bh; |
1d1fe1ee DH |
4485 | struct inode *inode; |
4486 | long ret; | |
ac27a0ec DK |
4487 | int block; |
4488 | ||
1d1fe1ee DH |
4489 | inode = iget_locked(sb, ino); |
4490 | if (!inode) | |
4491 | return ERR_PTR(-ENOMEM); | |
4492 | if (!(inode->i_state & I_NEW)) | |
4493 | return inode; | |
4494 | ||
4495 | ei = EXT4_I(inode); | |
03010a33 | 4496 | #ifdef CONFIG_EXT4_FS_POSIX_ACL |
617ba13b MC |
4497 | ei->i_acl = EXT4_ACL_NOT_CACHED; |
4498 | ei->i_default_acl = EXT4_ACL_NOT_CACHED; | |
ac27a0ec | 4499 | #endif |
ac27a0ec | 4500 | |
1d1fe1ee DH |
4501 | ret = __ext4_get_inode_loc(inode, &iloc, 0); |
4502 | if (ret < 0) | |
ac27a0ec DK |
4503 | goto bad_inode; |
4504 | bh = iloc.bh; | |
617ba13b | 4505 | raw_inode = ext4_raw_inode(&iloc); |
ac27a0ec DK |
4506 | inode->i_mode = le16_to_cpu(raw_inode->i_mode); |
4507 | inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low); | |
4508 | inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low); | |
af5bc92d | 4509 | if (!(test_opt(inode->i_sb, NO_UID32))) { |
ac27a0ec DK |
4510 | inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16; |
4511 | inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16; | |
4512 | } | |
4513 | inode->i_nlink = le16_to_cpu(raw_inode->i_links_count); | |
ac27a0ec DK |
4514 | |
4515 | ei->i_state = 0; | |
4516 | ei->i_dir_start_lookup = 0; | |
4517 | ei->i_dtime = le32_to_cpu(raw_inode->i_dtime); | |
4518 | /* We now have enough fields to check if the inode was active or not. | |
4519 | * This is needed because nfsd might try to access dead inodes | |
4520 | * the test is that same one that e2fsck uses | |
4521 | * NeilBrown 1999oct15 | |
4522 | */ | |
4523 | if (inode->i_nlink == 0) { | |
4524 | if (inode->i_mode == 0 || | |
617ba13b | 4525 | !(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) { |
ac27a0ec | 4526 | /* this inode is deleted */ |
af5bc92d | 4527 | brelse(bh); |
1d1fe1ee | 4528 | ret = -ESTALE; |
ac27a0ec DK |
4529 | goto bad_inode; |
4530 | } | |
4531 | /* The only unlinked inodes we let through here have | |
4532 | * valid i_mode and are being read by the orphan | |
4533 | * recovery code: that's fine, we're about to complete | |
4534 | * the process of deleting those. */ | |
4535 | } | |
ac27a0ec | 4536 | ei->i_flags = le32_to_cpu(raw_inode->i_flags); |
0fc1b451 | 4537 | inode->i_blocks = ext4_inode_blocks(raw_inode, ei); |
7973c0c1 | 4538 | ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl_lo); |
a9e81742 | 4539 | if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) |
a1ddeb7e BP |
4540 | ei->i_file_acl |= |
4541 | ((__u64)le16_to_cpu(raw_inode->i_file_acl_high)) << 32; | |
a48380f7 | 4542 | inode->i_size = ext4_isize(raw_inode); |
ac27a0ec DK |
4543 | ei->i_disksize = inode->i_size; |
4544 | inode->i_generation = le32_to_cpu(raw_inode->i_generation); | |
4545 | ei->i_block_group = iloc.block_group; | |
a4912123 | 4546 | ei->i_last_alloc_group = ~0; |
ac27a0ec DK |
4547 | /* |
4548 | * NOTE! The in-memory inode i_data array is in little-endian order | |
4549 | * even on big-endian machines: we do NOT byteswap the block numbers! | |
4550 | */ | |
617ba13b | 4551 | for (block = 0; block < EXT4_N_BLOCKS; block++) |
ac27a0ec DK |
4552 | ei->i_data[block] = raw_inode->i_block[block]; |
4553 | INIT_LIST_HEAD(&ei->i_orphan); | |
4554 | ||
0040d987 | 4555 | if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) { |
ac27a0ec | 4556 | ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize); |
617ba13b | 4557 | if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize > |
e5d2861f | 4558 | EXT4_INODE_SIZE(inode->i_sb)) { |
af5bc92d | 4559 | brelse(bh); |
1d1fe1ee | 4560 | ret = -EIO; |
ac27a0ec | 4561 | goto bad_inode; |
e5d2861f | 4562 | } |
ac27a0ec DK |
4563 | if (ei->i_extra_isize == 0) { |
4564 | /* The extra space is currently unused. Use it. */ | |
617ba13b MC |
4565 | ei->i_extra_isize = sizeof(struct ext4_inode) - |
4566 | EXT4_GOOD_OLD_INODE_SIZE; | |
ac27a0ec DK |
4567 | } else { |
4568 | __le32 *magic = (void *)raw_inode + | |
617ba13b | 4569 | EXT4_GOOD_OLD_INODE_SIZE + |
ac27a0ec | 4570 | ei->i_extra_isize; |
617ba13b MC |
4571 | if (*magic == cpu_to_le32(EXT4_XATTR_MAGIC)) |
4572 | ei->i_state |= EXT4_STATE_XATTR; | |
ac27a0ec DK |
4573 | } |
4574 | } else | |
4575 | ei->i_extra_isize = 0; | |
4576 | ||
ef7f3835 KS |
4577 | EXT4_INODE_GET_XTIME(i_ctime, inode, raw_inode); |
4578 | EXT4_INODE_GET_XTIME(i_mtime, inode, raw_inode); | |
4579 | EXT4_INODE_GET_XTIME(i_atime, inode, raw_inode); | |
4580 | EXT4_EINODE_GET_XTIME(i_crtime, ei, raw_inode); | |
4581 | ||
25ec56b5 JNC |
4582 | inode->i_version = le32_to_cpu(raw_inode->i_disk_version); |
4583 | if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) { | |
4584 | if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi)) | |
4585 | inode->i_version |= | |
4586 | (__u64)(le32_to_cpu(raw_inode->i_version_hi)) << 32; | |
4587 | } | |
4588 | ||
c4b5a614 | 4589 | ret = 0; |
485c26ec TT |
4590 | if (ei->i_file_acl && |
4591 | ((ei->i_file_acl < | |
4592 | (le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block) + | |
4593 | EXT4_SB(sb)->s_gdb_count)) || | |
4594 | (ei->i_file_acl >= ext4_blocks_count(EXT4_SB(sb)->s_es)))) { | |
4595 | ext4_error(sb, __func__, | |
4596 | "bad extended attribute block %llu in inode #%lu", | |
4597 | ei->i_file_acl, inode->i_ino); | |
4598 | ret = -EIO; | |
4599 | goto bad_inode; | |
4600 | } else if (ei->i_flags & EXT4_EXTENTS_FL) { | |
c4b5a614 TT |
4601 | if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || |
4602 | (S_ISLNK(inode->i_mode) && | |
4603 | !ext4_inode_is_fast_symlink(inode))) | |
4604 | /* Validate extent which is part of inode */ | |
4605 | ret = ext4_ext_check_inode(inode); | |
fe2c8191 TN |
4606 | } else if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || |
4607 | (S_ISLNK(inode->i_mode) && | |
4608 | !ext4_inode_is_fast_symlink(inode))) { | |
4609 | /* Validate block references which are part of inode */ | |
4610 | ret = ext4_check_inode_blockref(inode); | |
4611 | } | |
4612 | if (ret) { | |
4613 | brelse(bh); | |
4614 | goto bad_inode; | |
7a262f7c AK |
4615 | } |
4616 | ||
ac27a0ec | 4617 | if (S_ISREG(inode->i_mode)) { |
617ba13b MC |
4618 | inode->i_op = &ext4_file_inode_operations; |
4619 | inode->i_fop = &ext4_file_operations; | |
4620 | ext4_set_aops(inode); | |
ac27a0ec | 4621 | } else if (S_ISDIR(inode->i_mode)) { |
617ba13b MC |
4622 | inode->i_op = &ext4_dir_inode_operations; |
4623 | inode->i_fop = &ext4_dir_operations; | |
ac27a0ec | 4624 | } else if (S_ISLNK(inode->i_mode)) { |
e83c1397 | 4625 | if (ext4_inode_is_fast_symlink(inode)) { |
617ba13b | 4626 | inode->i_op = &ext4_fast_symlink_inode_operations; |
e83c1397 DG |
4627 | nd_terminate_link(ei->i_data, inode->i_size, |
4628 | sizeof(ei->i_data) - 1); | |
4629 | } else { | |
617ba13b MC |
4630 | inode->i_op = &ext4_symlink_inode_operations; |
4631 | ext4_set_aops(inode); | |
ac27a0ec | 4632 | } |
563bdd61 TT |
4633 | } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || |
4634 | S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { | |
617ba13b | 4635 | inode->i_op = &ext4_special_inode_operations; |
ac27a0ec DK |
4636 | if (raw_inode->i_block[0]) |
4637 | init_special_inode(inode, inode->i_mode, | |
4638 | old_decode_dev(le32_to_cpu(raw_inode->i_block[0]))); | |
4639 | else | |
4640 | init_special_inode(inode, inode->i_mode, | |
4641 | new_decode_dev(le32_to_cpu(raw_inode->i_block[1]))); | |
563bdd61 TT |
4642 | } else { |
4643 | brelse(bh); | |
4644 | ret = -EIO; | |
4645 | ext4_error(inode->i_sb, __func__, | |
4646 | "bogus i_mode (%o) for inode=%lu", | |
4647 | inode->i_mode, inode->i_ino); | |
4648 | goto bad_inode; | |
ac27a0ec | 4649 | } |
af5bc92d | 4650 | brelse(iloc.bh); |
617ba13b | 4651 | ext4_set_inode_flags(inode); |
1d1fe1ee DH |
4652 | unlock_new_inode(inode); |
4653 | return inode; | |
ac27a0ec DK |
4654 | |
4655 | bad_inode: | |
1d1fe1ee DH |
4656 | iget_failed(inode); |
4657 | return ERR_PTR(ret); | |
ac27a0ec DK |
4658 | } |
4659 | ||
0fc1b451 AK |
4660 | static int ext4_inode_blocks_set(handle_t *handle, |
4661 | struct ext4_inode *raw_inode, | |
4662 | struct ext4_inode_info *ei) | |
4663 | { | |
4664 | struct inode *inode = &(ei->vfs_inode); | |
4665 | u64 i_blocks = inode->i_blocks; | |
4666 | struct super_block *sb = inode->i_sb; | |
0fc1b451 AK |
4667 | |
4668 | if (i_blocks <= ~0U) { | |
4669 | /* | |
4670 | * i_blocks can be represnted in a 32 bit variable | |
4671 | * as multiple of 512 bytes | |
4672 | */ | |
8180a562 | 4673 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); |
0fc1b451 | 4674 | raw_inode->i_blocks_high = 0; |
8180a562 | 4675 | ei->i_flags &= ~EXT4_HUGE_FILE_FL; |
f287a1a5 TT |
4676 | return 0; |
4677 | } | |
4678 | if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) | |
4679 | return -EFBIG; | |
4680 | ||
4681 | if (i_blocks <= 0xffffffffffffULL) { | |
0fc1b451 AK |
4682 | /* |
4683 | * i_blocks can be represented in a 48 bit variable | |
4684 | * as multiple of 512 bytes | |
4685 | */ | |
8180a562 | 4686 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); |
0fc1b451 | 4687 | raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32); |
8180a562 | 4688 | ei->i_flags &= ~EXT4_HUGE_FILE_FL; |
0fc1b451 | 4689 | } else { |
8180a562 AK |
4690 | ei->i_flags |= EXT4_HUGE_FILE_FL; |
4691 | /* i_block is stored in file system block size */ | |
4692 | i_blocks = i_blocks >> (inode->i_blkbits - 9); | |
4693 | raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); | |
4694 | raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32); | |
0fc1b451 | 4695 | } |
f287a1a5 | 4696 | return 0; |
0fc1b451 AK |
4697 | } |
4698 | ||
ac27a0ec DK |
4699 | /* |
4700 | * Post the struct inode info into an on-disk inode location in the | |
4701 | * buffer-cache. This gobbles the caller's reference to the | |
4702 | * buffer_head in the inode location struct. | |
4703 | * | |
4704 | * The caller must have write access to iloc->bh. | |
4705 | */ | |
617ba13b | 4706 | static int ext4_do_update_inode(handle_t *handle, |
ac27a0ec | 4707 | struct inode *inode, |
617ba13b | 4708 | struct ext4_iloc *iloc) |
ac27a0ec | 4709 | { |
617ba13b MC |
4710 | struct ext4_inode *raw_inode = ext4_raw_inode(iloc); |
4711 | struct ext4_inode_info *ei = EXT4_I(inode); | |
ac27a0ec DK |
4712 | struct buffer_head *bh = iloc->bh; |
4713 | int err = 0, rc, block; | |
4714 | ||
4715 | /* For fields not not tracking in the in-memory inode, | |
4716 | * initialise them to zero for new inodes. */ | |
617ba13b MC |
4717 | if (ei->i_state & EXT4_STATE_NEW) |
4718 | memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); | |
ac27a0ec | 4719 | |
ff9ddf7e | 4720 | ext4_get_inode_flags(ei); |
ac27a0ec | 4721 | raw_inode->i_mode = cpu_to_le16(inode->i_mode); |
af5bc92d | 4722 | if (!(test_opt(inode->i_sb, NO_UID32))) { |
ac27a0ec DK |
4723 | raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid)); |
4724 | raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid)); | |
4725 | /* | |
4726 | * Fix up interoperability with old kernels. Otherwise, old inodes get | |
4727 | * re-used with the upper 16 bits of the uid/gid intact | |
4728 | */ | |
af5bc92d | 4729 | if (!ei->i_dtime) { |
ac27a0ec DK |
4730 | raw_inode->i_uid_high = |
4731 | cpu_to_le16(high_16_bits(inode->i_uid)); | |
4732 | raw_inode->i_gid_high = | |
4733 | cpu_to_le16(high_16_bits(inode->i_gid)); | |
4734 | } else { | |
4735 | raw_inode->i_uid_high = 0; | |
4736 | raw_inode->i_gid_high = 0; | |
4737 | } | |
4738 | } else { | |
4739 | raw_inode->i_uid_low = | |
4740 | cpu_to_le16(fs_high2lowuid(inode->i_uid)); | |
4741 | raw_inode->i_gid_low = | |
4742 | cpu_to_le16(fs_high2lowgid(inode->i_gid)); | |
4743 | raw_inode->i_uid_high = 0; | |
4744 | raw_inode->i_gid_high = 0; | |
4745 | } | |
4746 | raw_inode->i_links_count = cpu_to_le16(inode->i_nlink); | |
ef7f3835 KS |
4747 | |
4748 | EXT4_INODE_SET_XTIME(i_ctime, inode, raw_inode); | |
4749 | EXT4_INODE_SET_XTIME(i_mtime, inode, raw_inode); | |
4750 | EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode); | |
4751 | EXT4_EINODE_SET_XTIME(i_crtime, ei, raw_inode); | |
4752 | ||
0fc1b451 AK |
4753 | if (ext4_inode_blocks_set(handle, raw_inode, ei)) |
4754 | goto out_brelse; | |
ac27a0ec | 4755 | raw_inode->i_dtime = cpu_to_le32(ei->i_dtime); |
267e4db9 AK |
4756 | /* clear the migrate flag in the raw_inode */ |
4757 | raw_inode->i_flags = cpu_to_le32(ei->i_flags & ~EXT4_EXT_MIGRATE); | |
9b8f1f01 MC |
4758 | if (EXT4_SB(inode->i_sb)->s_es->s_creator_os != |
4759 | cpu_to_le32(EXT4_OS_HURD)) | |
a1ddeb7e BP |
4760 | raw_inode->i_file_acl_high = |
4761 | cpu_to_le16(ei->i_file_acl >> 32); | |
7973c0c1 | 4762 | raw_inode->i_file_acl_lo = cpu_to_le32(ei->i_file_acl); |
a48380f7 AK |
4763 | ext4_isize_set(raw_inode, ei->i_disksize); |
4764 | if (ei->i_disksize > 0x7fffffffULL) { | |
4765 | struct super_block *sb = inode->i_sb; | |
4766 | if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, | |
4767 | EXT4_FEATURE_RO_COMPAT_LARGE_FILE) || | |
4768 | EXT4_SB(sb)->s_es->s_rev_level == | |
4769 | cpu_to_le32(EXT4_GOOD_OLD_REV)) { | |
4770 | /* If this is the first large file | |
4771 | * created, add a flag to the superblock. | |
4772 | */ | |
4773 | err = ext4_journal_get_write_access(handle, | |
4774 | EXT4_SB(sb)->s_sbh); | |
4775 | if (err) | |
4776 | goto out_brelse; | |
4777 | ext4_update_dynamic_rev(sb); | |
4778 | EXT4_SET_RO_COMPAT_FEATURE(sb, | |
617ba13b | 4779 | EXT4_FEATURE_RO_COMPAT_LARGE_FILE); |
a48380f7 | 4780 | sb->s_dirt = 1; |
0390131b FM |
4781 | ext4_handle_sync(handle); |
4782 | err = ext4_handle_dirty_metadata(handle, inode, | |
a48380f7 | 4783 | EXT4_SB(sb)->s_sbh); |
ac27a0ec DK |
4784 | } |
4785 | } | |
4786 | raw_inode->i_generation = cpu_to_le32(inode->i_generation); | |
4787 | if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { | |
4788 | if (old_valid_dev(inode->i_rdev)) { | |
4789 | raw_inode->i_block[0] = | |
4790 | cpu_to_le32(old_encode_dev(inode->i_rdev)); | |
4791 | raw_inode->i_block[1] = 0; | |
4792 | } else { | |
4793 | raw_inode->i_block[0] = 0; | |
4794 | raw_inode->i_block[1] = | |
4795 | cpu_to_le32(new_encode_dev(inode->i_rdev)); | |
4796 | raw_inode->i_block[2] = 0; | |
4797 | } | |
617ba13b | 4798 | } else for (block = 0; block < EXT4_N_BLOCKS; block++) |
ac27a0ec DK |
4799 | raw_inode->i_block[block] = ei->i_data[block]; |
4800 | ||
25ec56b5 JNC |
4801 | raw_inode->i_disk_version = cpu_to_le32(inode->i_version); |
4802 | if (ei->i_extra_isize) { | |
4803 | if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi)) | |
4804 | raw_inode->i_version_hi = | |
4805 | cpu_to_le32(inode->i_version >> 32); | |
ac27a0ec | 4806 | raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize); |
25ec56b5 JNC |
4807 | } |
4808 | ||
0390131b FM |
4809 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
4810 | rc = ext4_handle_dirty_metadata(handle, inode, bh); | |
ac27a0ec DK |
4811 | if (!err) |
4812 | err = rc; | |
617ba13b | 4813 | ei->i_state &= ~EXT4_STATE_NEW; |
ac27a0ec DK |
4814 | |
4815 | out_brelse: | |
af5bc92d | 4816 | brelse(bh); |
617ba13b | 4817 | ext4_std_error(inode->i_sb, err); |
ac27a0ec DK |
4818 | return err; |
4819 | } | |
4820 | ||
4821 | /* | |
617ba13b | 4822 | * ext4_write_inode() |
ac27a0ec DK |
4823 | * |
4824 | * We are called from a few places: | |
4825 | * | |
4826 | * - Within generic_file_write() for O_SYNC files. | |
4827 | * Here, there will be no transaction running. We wait for any running | |
4828 | * trasnaction to commit. | |
4829 | * | |
4830 | * - Within sys_sync(), kupdate and such. | |
4831 | * We wait on commit, if tol to. | |
4832 | * | |
4833 | * - Within prune_icache() (PF_MEMALLOC == true) | |
4834 | * Here we simply return. We can't afford to block kswapd on the | |
4835 | * journal commit. | |
4836 | * | |
4837 | * In all cases it is actually safe for us to return without doing anything, | |
4838 | * because the inode has been copied into a raw inode buffer in | |
617ba13b | 4839 | * ext4_mark_inode_dirty(). This is a correctness thing for O_SYNC and for |
ac27a0ec DK |
4840 | * knfsd. |
4841 | * | |
4842 | * Note that we are absolutely dependent upon all inode dirtiers doing the | |
4843 | * right thing: they *must* call mark_inode_dirty() after dirtying info in | |
4844 | * which we are interested. | |
4845 | * | |
4846 | * It would be a bug for them to not do this. The code: | |
4847 | * | |
4848 | * mark_inode_dirty(inode) | |
4849 | * stuff(); | |
4850 | * inode->i_size = expr; | |
4851 | * | |
4852 | * is in error because a kswapd-driven write_inode() could occur while | |
4853 | * `stuff()' is running, and the new i_size will be lost. Plus the inode | |
4854 | * will no longer be on the superblock's dirty inode list. | |
4855 | */ | |
617ba13b | 4856 | int ext4_write_inode(struct inode *inode, int wait) |
ac27a0ec DK |
4857 | { |
4858 | if (current->flags & PF_MEMALLOC) | |
4859 | return 0; | |
4860 | ||
617ba13b | 4861 | if (ext4_journal_current_handle()) { |
b38bd33a | 4862 | jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n"); |
ac27a0ec DK |
4863 | dump_stack(); |
4864 | return -EIO; | |
4865 | } | |
4866 | ||
4867 | if (!wait) | |
4868 | return 0; | |
4869 | ||
617ba13b | 4870 | return ext4_force_commit(inode->i_sb); |
ac27a0ec DK |
4871 | } |
4872 | ||
4873 | /* | |
617ba13b | 4874 | * ext4_setattr() |
ac27a0ec DK |
4875 | * |
4876 | * Called from notify_change. | |
4877 | * | |
4878 | * We want to trap VFS attempts to truncate the file as soon as | |
4879 | * possible. In particular, we want to make sure that when the VFS | |
4880 | * shrinks i_size, we put the inode on the orphan list and modify | |
4881 | * i_disksize immediately, so that during the subsequent flushing of | |
4882 | * dirty pages and freeing of disk blocks, we can guarantee that any | |
4883 | * commit will leave the blocks being flushed in an unused state on | |
4884 | * disk. (On recovery, the inode will get truncated and the blocks will | |
4885 | * be freed, so we have a strong guarantee that no future commit will | |
4886 | * leave these blocks visible to the user.) | |
4887 | * | |
678aaf48 JK |
4888 | * Another thing we have to assure is that if we are in ordered mode |
4889 | * and inode is still attached to the committing transaction, we must | |
4890 | * we start writeout of all the dirty pages which are being truncated. | |
4891 | * This way we are sure that all the data written in the previous | |
4892 | * transaction are already on disk (truncate waits for pages under | |
4893 | * writeback). | |
4894 | * | |
4895 | * Called with inode->i_mutex down. | |
ac27a0ec | 4896 | */ |
617ba13b | 4897 | int ext4_setattr(struct dentry *dentry, struct iattr *attr) |
ac27a0ec DK |
4898 | { |
4899 | struct inode *inode = dentry->d_inode; | |
4900 | int error, rc = 0; | |
4901 | const unsigned int ia_valid = attr->ia_valid; | |
4902 | ||
4903 | error = inode_change_ok(inode, attr); | |
4904 | if (error) | |
4905 | return error; | |
4906 | ||
4907 | if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) || | |
4908 | (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) { | |
4909 | handle_t *handle; | |
4910 | ||
4911 | /* (user+group)*(old+new) structure, inode write (sb, | |
4912 | * inode block, ? - but truncate inode update has it) */ | |
617ba13b MC |
4913 | handle = ext4_journal_start(inode, 2*(EXT4_QUOTA_INIT_BLOCKS(inode->i_sb)+ |
4914 | EXT4_QUOTA_DEL_BLOCKS(inode->i_sb))+3); | |
ac27a0ec DK |
4915 | if (IS_ERR(handle)) { |
4916 | error = PTR_ERR(handle); | |
4917 | goto err_out; | |
4918 | } | |
a269eb18 | 4919 | error = vfs_dq_transfer(inode, attr) ? -EDQUOT : 0; |
ac27a0ec | 4920 | if (error) { |
617ba13b | 4921 | ext4_journal_stop(handle); |
ac27a0ec DK |
4922 | return error; |
4923 | } | |
4924 | /* Update corresponding info in inode so that everything is in | |
4925 | * one transaction */ | |
4926 | if (attr->ia_valid & ATTR_UID) | |
4927 | inode->i_uid = attr->ia_uid; | |
4928 | if (attr->ia_valid & ATTR_GID) | |
4929 | inode->i_gid = attr->ia_gid; | |
617ba13b MC |
4930 | error = ext4_mark_inode_dirty(handle, inode); |
4931 | ext4_journal_stop(handle); | |
ac27a0ec DK |
4932 | } |
4933 | ||
e2b46574 ES |
4934 | if (attr->ia_valid & ATTR_SIZE) { |
4935 | if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) { | |
4936 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); | |
4937 | ||
4938 | if (attr->ia_size > sbi->s_bitmap_maxbytes) { | |
4939 | error = -EFBIG; | |
4940 | goto err_out; | |
4941 | } | |
4942 | } | |
4943 | } | |
4944 | ||
ac27a0ec DK |
4945 | if (S_ISREG(inode->i_mode) && |
4946 | attr->ia_valid & ATTR_SIZE && attr->ia_size < inode->i_size) { | |
4947 | handle_t *handle; | |
4948 | ||
617ba13b | 4949 | handle = ext4_journal_start(inode, 3); |
ac27a0ec DK |
4950 | if (IS_ERR(handle)) { |
4951 | error = PTR_ERR(handle); | |
4952 | goto err_out; | |
4953 | } | |
4954 | ||
617ba13b MC |
4955 | error = ext4_orphan_add(handle, inode); |
4956 | EXT4_I(inode)->i_disksize = attr->ia_size; | |
4957 | rc = ext4_mark_inode_dirty(handle, inode); | |
ac27a0ec DK |
4958 | if (!error) |
4959 | error = rc; | |
617ba13b | 4960 | ext4_journal_stop(handle); |
678aaf48 JK |
4961 | |
4962 | if (ext4_should_order_data(inode)) { | |
4963 | error = ext4_begin_ordered_truncate(inode, | |
4964 | attr->ia_size); | |
4965 | if (error) { | |
4966 | /* Do as much error cleanup as possible */ | |
4967 | handle = ext4_journal_start(inode, 3); | |
4968 | if (IS_ERR(handle)) { | |
4969 | ext4_orphan_del(NULL, inode); | |
4970 | goto err_out; | |
4971 | } | |
4972 | ext4_orphan_del(handle, inode); | |
4973 | ext4_journal_stop(handle); | |
4974 | goto err_out; | |
4975 | } | |
4976 | } | |
ac27a0ec DK |
4977 | } |
4978 | ||
4979 | rc = inode_setattr(inode, attr); | |
4980 | ||
617ba13b | 4981 | /* If inode_setattr's call to ext4_truncate failed to get a |
ac27a0ec DK |
4982 | * transaction handle at all, we need to clean up the in-core |
4983 | * orphan list manually. */ | |
4984 | if (inode->i_nlink) | |
617ba13b | 4985 | ext4_orphan_del(NULL, inode); |
ac27a0ec DK |
4986 | |
4987 | if (!rc && (ia_valid & ATTR_MODE)) | |
617ba13b | 4988 | rc = ext4_acl_chmod(inode); |
ac27a0ec DK |
4989 | |
4990 | err_out: | |
617ba13b | 4991 | ext4_std_error(inode->i_sb, error); |
ac27a0ec DK |
4992 | if (!error) |
4993 | error = rc; | |
4994 | return error; | |
4995 | } | |
4996 | ||
3e3398a0 MC |
4997 | int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry, |
4998 | struct kstat *stat) | |
4999 | { | |
5000 | struct inode *inode; | |
5001 | unsigned long delalloc_blocks; | |
5002 | ||
5003 | inode = dentry->d_inode; | |
5004 | generic_fillattr(inode, stat); | |
5005 | ||
5006 | /* | |
5007 | * We can't update i_blocks if the block allocation is delayed | |
5008 | * otherwise in the case of system crash before the real block | |
5009 | * allocation is done, we will have i_blocks inconsistent with | |
5010 | * on-disk file blocks. | |
5011 | * We always keep i_blocks updated together with real | |
5012 | * allocation. But to not confuse with user, stat | |
5013 | * will return the blocks that include the delayed allocation | |
5014 | * blocks for this file. | |
5015 | */ | |
5016 | spin_lock(&EXT4_I(inode)->i_block_reservation_lock); | |
5017 | delalloc_blocks = EXT4_I(inode)->i_reserved_data_blocks; | |
5018 | spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); | |
5019 | ||
5020 | stat->blocks += (delalloc_blocks << inode->i_sb->s_blocksize_bits)>>9; | |
5021 | return 0; | |
5022 | } | |
ac27a0ec | 5023 | |
a02908f1 MC |
5024 | static int ext4_indirect_trans_blocks(struct inode *inode, int nrblocks, |
5025 | int chunk) | |
5026 | { | |
5027 | int indirects; | |
5028 | ||
5029 | /* if nrblocks are contiguous */ | |
5030 | if (chunk) { | |
5031 | /* | |
5032 | * With N contiguous data blocks, it need at most | |
5033 | * N/EXT4_ADDR_PER_BLOCK(inode->i_sb) indirect blocks | |
5034 | * 2 dindirect blocks | |
5035 | * 1 tindirect block | |
5036 | */ | |
5037 | indirects = nrblocks / EXT4_ADDR_PER_BLOCK(inode->i_sb); | |
5038 | return indirects + 3; | |
5039 | } | |
5040 | /* | |
5041 | * if nrblocks are not contiguous, worse case, each block touch | |
5042 | * a indirect block, and each indirect block touch a double indirect | |
5043 | * block, plus a triple indirect block | |
5044 | */ | |
5045 | indirects = nrblocks * 2 + 1; | |
5046 | return indirects; | |
5047 | } | |
5048 | ||
5049 | static int ext4_index_trans_blocks(struct inode *inode, int nrblocks, int chunk) | |
5050 | { | |
5051 | if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) | |
ac51d837 TT |
5052 | return ext4_indirect_trans_blocks(inode, nrblocks, chunk); |
5053 | return ext4_ext_index_trans_blocks(inode, nrblocks, chunk); | |
a02908f1 | 5054 | } |
ac51d837 | 5055 | |
ac27a0ec | 5056 | /* |
a02908f1 MC |
5057 | * Account for index blocks, block groups bitmaps and block group |
5058 | * descriptor blocks if modify datablocks and index blocks | |
5059 | * worse case, the indexs blocks spread over different block groups | |
ac27a0ec | 5060 | * |
a02908f1 MC |
5061 | * If datablocks are discontiguous, they are possible to spread over |
5062 | * different block groups too. If they are contiugous, with flexbg, | |
5063 | * they could still across block group boundary. | |
ac27a0ec | 5064 | * |
a02908f1 MC |
5065 | * Also account for superblock, inode, quota and xattr blocks |
5066 | */ | |
5067 | int ext4_meta_trans_blocks(struct inode *inode, int nrblocks, int chunk) | |
5068 | { | |
8df9675f TT |
5069 | ext4_group_t groups, ngroups = ext4_get_groups_count(inode->i_sb); |
5070 | int gdpblocks; | |
a02908f1 MC |
5071 | int idxblocks; |
5072 | int ret = 0; | |
5073 | ||
5074 | /* | |
5075 | * How many index blocks need to touch to modify nrblocks? | |
5076 | * The "Chunk" flag indicating whether the nrblocks is | |
5077 | * physically contiguous on disk | |
5078 | * | |
5079 | * For Direct IO and fallocate, they calls get_block to allocate | |
5080 | * one single extent at a time, so they could set the "Chunk" flag | |
5081 | */ | |
5082 | idxblocks = ext4_index_trans_blocks(inode, nrblocks, chunk); | |
5083 | ||
5084 | ret = idxblocks; | |
5085 | ||
5086 | /* | |
5087 | * Now let's see how many group bitmaps and group descriptors need | |
5088 | * to account | |
5089 | */ | |
5090 | groups = idxblocks; | |
5091 | if (chunk) | |
5092 | groups += 1; | |
5093 | else | |
5094 | groups += nrblocks; | |
5095 | ||
5096 | gdpblocks = groups; | |
8df9675f TT |
5097 | if (groups > ngroups) |
5098 | groups = ngroups; | |
a02908f1 MC |
5099 | if (groups > EXT4_SB(inode->i_sb)->s_gdb_count) |
5100 | gdpblocks = EXT4_SB(inode->i_sb)->s_gdb_count; | |
5101 | ||
5102 | /* bitmaps and block group descriptor blocks */ | |
5103 | ret += groups + gdpblocks; | |
5104 | ||
5105 | /* Blocks for super block, inode, quota and xattr blocks */ | |
5106 | ret += EXT4_META_TRANS_BLOCKS(inode->i_sb); | |
5107 | ||
5108 | return ret; | |
5109 | } | |
5110 | ||
5111 | /* | |
5112 | * Calulate the total number of credits to reserve to fit | |
f3bd1f3f MC |
5113 | * the modification of a single pages into a single transaction, |
5114 | * which may include multiple chunks of block allocations. | |
ac27a0ec | 5115 | * |
525f4ed8 | 5116 | * This could be called via ext4_write_begin() |
ac27a0ec | 5117 | * |
525f4ed8 | 5118 | * We need to consider the worse case, when |
a02908f1 | 5119 | * one new block per extent. |
ac27a0ec | 5120 | */ |
a86c6181 | 5121 | int ext4_writepage_trans_blocks(struct inode *inode) |
ac27a0ec | 5122 | { |
617ba13b | 5123 | int bpp = ext4_journal_blocks_per_page(inode); |
ac27a0ec DK |
5124 | int ret; |
5125 | ||
a02908f1 | 5126 | ret = ext4_meta_trans_blocks(inode, bpp, 0); |
a86c6181 | 5127 | |
a02908f1 | 5128 | /* Account for data blocks for journalled mode */ |
617ba13b | 5129 | if (ext4_should_journal_data(inode)) |
a02908f1 | 5130 | ret += bpp; |
ac27a0ec DK |
5131 | return ret; |
5132 | } | |
f3bd1f3f MC |
5133 | |
5134 | /* | |
5135 | * Calculate the journal credits for a chunk of data modification. | |
5136 | * | |
5137 | * This is called from DIO, fallocate or whoever calling | |
12b7ac17 | 5138 | * ext4_get_blocks() to map/allocate a chunk of contigous disk blocks. |
f3bd1f3f MC |
5139 | * |
5140 | * journal buffers for data blocks are not included here, as DIO | |
5141 | * and fallocate do no need to journal data buffers. | |
5142 | */ | |
5143 | int ext4_chunk_trans_blocks(struct inode *inode, int nrblocks) | |
5144 | { | |
5145 | return ext4_meta_trans_blocks(inode, nrblocks, 1); | |
5146 | } | |
5147 | ||
ac27a0ec | 5148 | /* |
617ba13b | 5149 | * The caller must have previously called ext4_reserve_inode_write(). |
ac27a0ec DK |
5150 | * Give this, we know that the caller already has write access to iloc->bh. |
5151 | */ | |
617ba13b MC |
5152 | int ext4_mark_iloc_dirty(handle_t *handle, |
5153 | struct inode *inode, struct ext4_iloc *iloc) | |
ac27a0ec DK |
5154 | { |
5155 | int err = 0; | |
5156 | ||
25ec56b5 JNC |
5157 | if (test_opt(inode->i_sb, I_VERSION)) |
5158 | inode_inc_iversion(inode); | |
5159 | ||
ac27a0ec DK |
5160 | /* the do_update_inode consumes one bh->b_count */ |
5161 | get_bh(iloc->bh); | |
5162 | ||
dab291af | 5163 | /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */ |
617ba13b | 5164 | err = ext4_do_update_inode(handle, inode, iloc); |
ac27a0ec DK |
5165 | put_bh(iloc->bh); |
5166 | return err; | |
5167 | } | |
5168 | ||
5169 | /* | |
5170 | * On success, We end up with an outstanding reference count against | |
5171 | * iloc->bh. This _must_ be cleaned up later. | |
5172 | */ | |
5173 | ||
5174 | int | |
617ba13b MC |
5175 | ext4_reserve_inode_write(handle_t *handle, struct inode *inode, |
5176 | struct ext4_iloc *iloc) | |
ac27a0ec | 5177 | { |
0390131b FM |
5178 | int err; |
5179 | ||
5180 | err = ext4_get_inode_loc(inode, iloc); | |
5181 | if (!err) { | |
5182 | BUFFER_TRACE(iloc->bh, "get_write_access"); | |
5183 | err = ext4_journal_get_write_access(handle, iloc->bh); | |
5184 | if (err) { | |
5185 | brelse(iloc->bh); | |
5186 | iloc->bh = NULL; | |
ac27a0ec DK |
5187 | } |
5188 | } | |
617ba13b | 5189 | ext4_std_error(inode->i_sb, err); |
ac27a0ec DK |
5190 | return err; |
5191 | } | |
5192 | ||
6dd4ee7c KS |
5193 | /* |
5194 | * Expand an inode by new_extra_isize bytes. | |
5195 | * Returns 0 on success or negative error number on failure. | |
5196 | */ | |
1d03ec98 AK |
5197 | static int ext4_expand_extra_isize(struct inode *inode, |
5198 | unsigned int new_extra_isize, | |
5199 | struct ext4_iloc iloc, | |
5200 | handle_t *handle) | |
6dd4ee7c KS |
5201 | { |
5202 | struct ext4_inode *raw_inode; | |
5203 | struct ext4_xattr_ibody_header *header; | |
5204 | struct ext4_xattr_entry *entry; | |
5205 | ||
5206 | if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) | |
5207 | return 0; | |
5208 | ||
5209 | raw_inode = ext4_raw_inode(&iloc); | |
5210 | ||
5211 | header = IHDR(inode, raw_inode); | |
5212 | entry = IFIRST(header); | |
5213 | ||
5214 | /* No extended attributes present */ | |
5215 | if (!(EXT4_I(inode)->i_state & EXT4_STATE_XATTR) || | |
5216 | header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)) { | |
5217 | memset((void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE, 0, | |
5218 | new_extra_isize); | |
5219 | EXT4_I(inode)->i_extra_isize = new_extra_isize; | |
5220 | return 0; | |
5221 | } | |
5222 | ||
5223 | /* try to expand with EAs present */ | |
5224 | return ext4_expand_extra_isize_ea(inode, new_extra_isize, | |
5225 | raw_inode, handle); | |
5226 | } | |
5227 | ||
ac27a0ec DK |
5228 | /* |
5229 | * What we do here is to mark the in-core inode as clean with respect to inode | |
5230 | * dirtiness (it may still be data-dirty). | |
5231 | * This means that the in-core inode may be reaped by prune_icache | |
5232 | * without having to perform any I/O. This is a very good thing, | |
5233 | * because *any* task may call prune_icache - even ones which | |
5234 | * have a transaction open against a different journal. | |
5235 | * | |
5236 | * Is this cheating? Not really. Sure, we haven't written the | |
5237 | * inode out, but prune_icache isn't a user-visible syncing function. | |
5238 | * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync) | |
5239 | * we start and wait on commits. | |
5240 | * | |
5241 | * Is this efficient/effective? Well, we're being nice to the system | |
5242 | * by cleaning up our inodes proactively so they can be reaped | |
5243 | * without I/O. But we are potentially leaving up to five seconds' | |
5244 | * worth of inodes floating about which prune_icache wants us to | |
5245 | * write out. One way to fix that would be to get prune_icache() | |
5246 | * to do a write_super() to free up some memory. It has the desired | |
5247 | * effect. | |
5248 | */ | |
617ba13b | 5249 | int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode) |
ac27a0ec | 5250 | { |
617ba13b | 5251 | struct ext4_iloc iloc; |
6dd4ee7c KS |
5252 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
5253 | static unsigned int mnt_count; | |
5254 | int err, ret; | |
ac27a0ec DK |
5255 | |
5256 | might_sleep(); | |
617ba13b | 5257 | err = ext4_reserve_inode_write(handle, inode, &iloc); |
0390131b FM |
5258 | if (ext4_handle_valid(handle) && |
5259 | EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize && | |
6dd4ee7c KS |
5260 | !(EXT4_I(inode)->i_state & EXT4_STATE_NO_EXPAND)) { |
5261 | /* | |
5262 | * We need extra buffer credits since we may write into EA block | |
5263 | * with this same handle. If journal_extend fails, then it will | |
5264 | * only result in a minor loss of functionality for that inode. | |
5265 | * If this is felt to be critical, then e2fsck should be run to | |
5266 | * force a large enough s_min_extra_isize. | |
5267 | */ | |
5268 | if ((jbd2_journal_extend(handle, | |
5269 | EXT4_DATA_TRANS_BLOCKS(inode->i_sb))) == 0) { | |
5270 | ret = ext4_expand_extra_isize(inode, | |
5271 | sbi->s_want_extra_isize, | |
5272 | iloc, handle); | |
5273 | if (ret) { | |
5274 | EXT4_I(inode)->i_state |= EXT4_STATE_NO_EXPAND; | |
c1bddad9 AK |
5275 | if (mnt_count != |
5276 | le16_to_cpu(sbi->s_es->s_mnt_count)) { | |
46e665e9 | 5277 | ext4_warning(inode->i_sb, __func__, |
6dd4ee7c KS |
5278 | "Unable to expand inode %lu. Delete" |
5279 | " some EAs or run e2fsck.", | |
5280 | inode->i_ino); | |
c1bddad9 AK |
5281 | mnt_count = |
5282 | le16_to_cpu(sbi->s_es->s_mnt_count); | |
6dd4ee7c KS |
5283 | } |
5284 | } | |
5285 | } | |
5286 | } | |
ac27a0ec | 5287 | if (!err) |
617ba13b | 5288 | err = ext4_mark_iloc_dirty(handle, inode, &iloc); |
ac27a0ec DK |
5289 | return err; |
5290 | } | |
5291 | ||
5292 | /* | |
617ba13b | 5293 | * ext4_dirty_inode() is called from __mark_inode_dirty() |
ac27a0ec DK |
5294 | * |
5295 | * We're really interested in the case where a file is being extended. | |
5296 | * i_size has been changed by generic_commit_write() and we thus need | |
5297 | * to include the updated inode in the current transaction. | |
5298 | * | |
a269eb18 | 5299 | * Also, vfs_dq_alloc_block() will always dirty the inode when blocks |
ac27a0ec DK |
5300 | * are allocated to the file. |
5301 | * | |
5302 | * If the inode is marked synchronous, we don't honour that here - doing | |
5303 | * so would cause a commit on atime updates, which we don't bother doing. | |
5304 | * We handle synchronous inodes at the highest possible level. | |
5305 | */ | |
617ba13b | 5306 | void ext4_dirty_inode(struct inode *inode) |
ac27a0ec | 5307 | { |
617ba13b | 5308 | handle_t *current_handle = ext4_journal_current_handle(); |
ac27a0ec DK |
5309 | handle_t *handle; |
5310 | ||
0390131b FM |
5311 | if (!ext4_handle_valid(current_handle)) { |
5312 | ext4_mark_inode_dirty(current_handle, inode); | |
5313 | return; | |
5314 | } | |
5315 | ||
617ba13b | 5316 | handle = ext4_journal_start(inode, 2); |
ac27a0ec DK |
5317 | if (IS_ERR(handle)) |
5318 | goto out; | |
5319 | if (current_handle && | |
5320 | current_handle->h_transaction != handle->h_transaction) { | |
5321 | /* This task has a transaction open against a different fs */ | |
5322 | printk(KERN_EMERG "%s: transactions do not match!\n", | |
46e665e9 | 5323 | __func__); |
ac27a0ec DK |
5324 | } else { |
5325 | jbd_debug(5, "marking dirty. outer handle=%p\n", | |
5326 | current_handle); | |
617ba13b | 5327 | ext4_mark_inode_dirty(handle, inode); |
ac27a0ec | 5328 | } |
617ba13b | 5329 | ext4_journal_stop(handle); |
ac27a0ec DK |
5330 | out: |
5331 | return; | |
5332 | } | |
5333 | ||
5334 | #if 0 | |
5335 | /* | |
5336 | * Bind an inode's backing buffer_head into this transaction, to prevent | |
5337 | * it from being flushed to disk early. Unlike | |
617ba13b | 5338 | * ext4_reserve_inode_write, this leaves behind no bh reference and |
ac27a0ec DK |
5339 | * returns no iloc structure, so the caller needs to repeat the iloc |
5340 | * lookup to mark the inode dirty later. | |
5341 | */ | |
617ba13b | 5342 | static int ext4_pin_inode(handle_t *handle, struct inode *inode) |
ac27a0ec | 5343 | { |
617ba13b | 5344 | struct ext4_iloc iloc; |
ac27a0ec DK |
5345 | |
5346 | int err = 0; | |
5347 | if (handle) { | |
617ba13b | 5348 | err = ext4_get_inode_loc(inode, &iloc); |
ac27a0ec DK |
5349 | if (!err) { |
5350 | BUFFER_TRACE(iloc.bh, "get_write_access"); | |
dab291af | 5351 | err = jbd2_journal_get_write_access(handle, iloc.bh); |
ac27a0ec | 5352 | if (!err) |
0390131b FM |
5353 | err = ext4_handle_dirty_metadata(handle, |
5354 | inode, | |
5355 | iloc.bh); | |
ac27a0ec DK |
5356 | brelse(iloc.bh); |
5357 | } | |
5358 | } | |
617ba13b | 5359 | ext4_std_error(inode->i_sb, err); |
ac27a0ec DK |
5360 | return err; |
5361 | } | |
5362 | #endif | |
5363 | ||
617ba13b | 5364 | int ext4_change_inode_journal_flag(struct inode *inode, int val) |
ac27a0ec DK |
5365 | { |
5366 | journal_t *journal; | |
5367 | handle_t *handle; | |
5368 | int err; | |
5369 | ||
5370 | /* | |
5371 | * We have to be very careful here: changing a data block's | |
5372 | * journaling status dynamically is dangerous. If we write a | |
5373 | * data block to the journal, change the status and then delete | |
5374 | * that block, we risk forgetting to revoke the old log record | |
5375 | * from the journal and so a subsequent replay can corrupt data. | |
5376 | * So, first we make sure that the journal is empty and that | |
5377 | * nobody is changing anything. | |
5378 | */ | |
5379 | ||
617ba13b | 5380 | journal = EXT4_JOURNAL(inode); |
0390131b FM |
5381 | if (!journal) |
5382 | return 0; | |
d699594d | 5383 | if (is_journal_aborted(journal)) |
ac27a0ec DK |
5384 | return -EROFS; |
5385 | ||
dab291af MC |
5386 | jbd2_journal_lock_updates(journal); |
5387 | jbd2_journal_flush(journal); | |
ac27a0ec DK |
5388 | |
5389 | /* | |
5390 | * OK, there are no updates running now, and all cached data is | |
5391 | * synced to disk. We are now in a completely consistent state | |
5392 | * which doesn't have anything in the journal, and we know that | |
5393 | * no filesystem updates are running, so it is safe to modify | |
5394 | * the inode's in-core data-journaling state flag now. | |
5395 | */ | |
5396 | ||
5397 | if (val) | |
617ba13b | 5398 | EXT4_I(inode)->i_flags |= EXT4_JOURNAL_DATA_FL; |
ac27a0ec | 5399 | else |
617ba13b MC |
5400 | EXT4_I(inode)->i_flags &= ~EXT4_JOURNAL_DATA_FL; |
5401 | ext4_set_aops(inode); | |
ac27a0ec | 5402 | |
dab291af | 5403 | jbd2_journal_unlock_updates(journal); |
ac27a0ec DK |
5404 | |
5405 | /* Finally we can mark the inode as dirty. */ | |
5406 | ||
617ba13b | 5407 | handle = ext4_journal_start(inode, 1); |
ac27a0ec DK |
5408 | if (IS_ERR(handle)) |
5409 | return PTR_ERR(handle); | |
5410 | ||
617ba13b | 5411 | err = ext4_mark_inode_dirty(handle, inode); |
0390131b | 5412 | ext4_handle_sync(handle); |
617ba13b MC |
5413 | ext4_journal_stop(handle); |
5414 | ext4_std_error(inode->i_sb, err); | |
ac27a0ec DK |
5415 | |
5416 | return err; | |
5417 | } | |
2e9ee850 AK |
5418 | |
5419 | static int ext4_bh_unmapped(handle_t *handle, struct buffer_head *bh) | |
5420 | { | |
5421 | return !buffer_mapped(bh); | |
5422 | } | |
5423 | ||
c2ec175c | 5424 | int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
2e9ee850 | 5425 | { |
c2ec175c | 5426 | struct page *page = vmf->page; |
2e9ee850 AK |
5427 | loff_t size; |
5428 | unsigned long len; | |
5429 | int ret = -EINVAL; | |
79f0be8d | 5430 | void *fsdata; |
2e9ee850 AK |
5431 | struct file *file = vma->vm_file; |
5432 | struct inode *inode = file->f_path.dentry->d_inode; | |
5433 | struct address_space *mapping = inode->i_mapping; | |
5434 | ||
5435 | /* | |
5436 | * Get i_alloc_sem to stop truncates messing with the inode. We cannot | |
5437 | * get i_mutex because we are already holding mmap_sem. | |
5438 | */ | |
5439 | down_read(&inode->i_alloc_sem); | |
5440 | size = i_size_read(inode); | |
5441 | if (page->mapping != mapping || size <= page_offset(page) | |
5442 | || !PageUptodate(page)) { | |
5443 | /* page got truncated from under us? */ | |
5444 | goto out_unlock; | |
5445 | } | |
5446 | ret = 0; | |
5447 | if (PageMappedToDisk(page)) | |
5448 | goto out_unlock; | |
5449 | ||
5450 | if (page->index == size >> PAGE_CACHE_SHIFT) | |
5451 | len = size & ~PAGE_CACHE_MASK; | |
5452 | else | |
5453 | len = PAGE_CACHE_SIZE; | |
5454 | ||
5455 | if (page_has_buffers(page)) { | |
5456 | /* return if we have all the buffers mapped */ | |
5457 | if (!walk_page_buffers(NULL, page_buffers(page), 0, len, NULL, | |
5458 | ext4_bh_unmapped)) | |
5459 | goto out_unlock; | |
5460 | } | |
5461 | /* | |
5462 | * OK, we need to fill the hole... Do write_begin write_end | |
5463 | * to do block allocation/reservation.We are not holding | |
5464 | * inode.i__mutex here. That allow * parallel write_begin, | |
5465 | * write_end call. lock_page prevent this from happening | |
5466 | * on the same page though | |
5467 | */ | |
5468 | ret = mapping->a_ops->write_begin(file, mapping, page_offset(page), | |
79f0be8d | 5469 | len, AOP_FLAG_UNINTERRUPTIBLE, &page, &fsdata); |
2e9ee850 AK |
5470 | if (ret < 0) |
5471 | goto out_unlock; | |
5472 | ret = mapping->a_ops->write_end(file, mapping, page_offset(page), | |
79f0be8d | 5473 | len, len, page, fsdata); |
2e9ee850 AK |
5474 | if (ret < 0) |
5475 | goto out_unlock; | |
5476 | ret = 0; | |
5477 | out_unlock: | |
c2ec175c NP |
5478 | if (ret) |
5479 | ret = VM_FAULT_SIGBUS; | |
2e9ee850 AK |
5480 | up_read(&inode->i_alloc_sem); |
5481 | return ret; | |
5482 | } |