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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/fs/affs/file.c | |
3 | * | |
4 | * (c) 1996 Hans-Joachim Widmaier - Rewritten | |
5 | * | |
6 | * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem. | |
7 | * | |
8 | * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem. | |
9 | * | |
10 | * (C) 1991 Linus Torvalds - minix filesystem | |
11 | * | |
12 | * affs regular file handling primitives | |
13 | */ | |
14 | ||
15 | #include "affs.h" | |
16 | ||
17 | #if PAGE_SIZE < 4096 | |
18 | #error PAGE_SIZE must be at least 4096 | |
19 | #endif | |
20 | ||
21 | static int affs_grow_extcache(struct inode *inode, u32 lc_idx); | |
22 | static struct buffer_head *affs_alloc_extblock(struct inode *inode, struct buffer_head *bh, u32 ext); | |
23 | static inline struct buffer_head *affs_get_extblock(struct inode *inode, u32 ext); | |
24 | static struct buffer_head *affs_get_extblock_slow(struct inode *inode, u32 ext); | |
1da177e4 LT |
25 | static int affs_file_open(struct inode *inode, struct file *filp); |
26 | static int affs_file_release(struct inode *inode, struct file *filp); | |
27 | ||
4b6f5d20 | 28 | const struct file_operations affs_file_operations = { |
1da177e4 LT |
29 | .llseek = generic_file_llseek, |
30 | .read = generic_file_read, | |
db73e9aa | 31 | .write = generic_file_write, |
1da177e4 LT |
32 | .mmap = generic_file_mmap, |
33 | .open = affs_file_open, | |
34 | .release = affs_file_release, | |
35 | .fsync = file_fsync, | |
36 | .sendfile = generic_file_sendfile, | |
37 | }; | |
38 | ||
39 | struct inode_operations affs_file_inode_operations = { | |
40 | .truncate = affs_truncate, | |
41 | .setattr = affs_notify_change, | |
42 | }; | |
43 | ||
44 | static int | |
45 | affs_file_open(struct inode *inode, struct file *filp) | |
46 | { | |
47 | if (atomic_read(&filp->f_count) != 1) | |
48 | return 0; | |
49 | pr_debug("AFFS: open(%d)\n", AFFS_I(inode)->i_opencnt); | |
50 | AFFS_I(inode)->i_opencnt++; | |
51 | return 0; | |
52 | } | |
53 | ||
54 | static int | |
55 | affs_file_release(struct inode *inode, struct file *filp) | |
56 | { | |
57 | if (atomic_read(&filp->f_count) != 0) | |
58 | return 0; | |
59 | pr_debug("AFFS: release(%d)\n", AFFS_I(inode)->i_opencnt); | |
60 | AFFS_I(inode)->i_opencnt--; | |
61 | if (!AFFS_I(inode)->i_opencnt) | |
62 | affs_free_prealloc(inode); | |
63 | ||
64 | return 0; | |
65 | } | |
66 | ||
67 | static int | |
68 | affs_grow_extcache(struct inode *inode, u32 lc_idx) | |
69 | { | |
70 | struct super_block *sb = inode->i_sb; | |
71 | struct buffer_head *bh; | |
72 | u32 lc_max; | |
73 | int i, j, key; | |
74 | ||
75 | if (!AFFS_I(inode)->i_lc) { | |
76 | char *ptr = (char *)get_zeroed_page(GFP_NOFS); | |
77 | if (!ptr) | |
78 | return -ENOMEM; | |
79 | AFFS_I(inode)->i_lc = (u32 *)ptr; | |
80 | AFFS_I(inode)->i_ac = (struct affs_ext_key *)(ptr + AFFS_CACHE_SIZE / 2); | |
81 | } | |
82 | ||
83 | lc_max = AFFS_LC_SIZE << AFFS_I(inode)->i_lc_shift; | |
84 | ||
85 | if (AFFS_I(inode)->i_extcnt > lc_max) { | |
86 | u32 lc_shift, lc_mask, tmp, off; | |
87 | ||
88 | /* need to recalculate linear cache, start from old size */ | |
89 | lc_shift = AFFS_I(inode)->i_lc_shift; | |
90 | tmp = (AFFS_I(inode)->i_extcnt / AFFS_LC_SIZE) >> lc_shift; | |
91 | for (; tmp; tmp >>= 1) | |
92 | lc_shift++; | |
93 | lc_mask = (1 << lc_shift) - 1; | |
94 | ||
95 | /* fix idx and old size to new shift */ | |
96 | lc_idx >>= (lc_shift - AFFS_I(inode)->i_lc_shift); | |
97 | AFFS_I(inode)->i_lc_size >>= (lc_shift - AFFS_I(inode)->i_lc_shift); | |
98 | ||
99 | /* first shrink old cache to make more space */ | |
100 | off = 1 << (lc_shift - AFFS_I(inode)->i_lc_shift); | |
101 | for (i = 1, j = off; j < AFFS_LC_SIZE; i++, j += off) | |
102 | AFFS_I(inode)->i_ac[i] = AFFS_I(inode)->i_ac[j]; | |
103 | ||
104 | AFFS_I(inode)->i_lc_shift = lc_shift; | |
105 | AFFS_I(inode)->i_lc_mask = lc_mask; | |
106 | } | |
107 | ||
108 | /* fill cache to the needed index */ | |
109 | i = AFFS_I(inode)->i_lc_size; | |
110 | AFFS_I(inode)->i_lc_size = lc_idx + 1; | |
111 | for (; i <= lc_idx; i++) { | |
112 | if (!i) { | |
113 | AFFS_I(inode)->i_lc[0] = inode->i_ino; | |
114 | continue; | |
115 | } | |
116 | key = AFFS_I(inode)->i_lc[i - 1]; | |
117 | j = AFFS_I(inode)->i_lc_mask + 1; | |
118 | // unlock cache | |
119 | for (; j > 0; j--) { | |
120 | bh = affs_bread(sb, key); | |
121 | if (!bh) | |
122 | goto err; | |
123 | key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); | |
124 | affs_brelse(bh); | |
125 | } | |
126 | // lock cache | |
127 | AFFS_I(inode)->i_lc[i] = key; | |
128 | } | |
129 | ||
130 | return 0; | |
131 | ||
132 | err: | |
133 | // lock cache | |
134 | return -EIO; | |
135 | } | |
136 | ||
137 | static struct buffer_head * | |
138 | affs_alloc_extblock(struct inode *inode, struct buffer_head *bh, u32 ext) | |
139 | { | |
140 | struct super_block *sb = inode->i_sb; | |
141 | struct buffer_head *new_bh; | |
142 | u32 blocknr, tmp; | |
143 | ||
144 | blocknr = affs_alloc_block(inode, bh->b_blocknr); | |
145 | if (!blocknr) | |
146 | return ERR_PTR(-ENOSPC); | |
147 | ||
148 | new_bh = affs_getzeroblk(sb, blocknr); | |
149 | if (!new_bh) { | |
150 | affs_free_block(sb, blocknr); | |
151 | return ERR_PTR(-EIO); | |
152 | } | |
153 | ||
154 | AFFS_HEAD(new_bh)->ptype = cpu_to_be32(T_LIST); | |
155 | AFFS_HEAD(new_bh)->key = cpu_to_be32(blocknr); | |
156 | AFFS_TAIL(sb, new_bh)->stype = cpu_to_be32(ST_FILE); | |
157 | AFFS_TAIL(sb, new_bh)->parent = cpu_to_be32(inode->i_ino); | |
158 | affs_fix_checksum(sb, new_bh); | |
159 | ||
160 | mark_buffer_dirty_inode(new_bh, inode); | |
161 | ||
162 | tmp = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); | |
163 | if (tmp) | |
164 | affs_warning(sb, "alloc_ext", "previous extension set (%x)", tmp); | |
165 | AFFS_TAIL(sb, bh)->extension = cpu_to_be32(blocknr); | |
166 | affs_adjust_checksum(bh, blocknr - tmp); | |
167 | mark_buffer_dirty_inode(bh, inode); | |
168 | ||
169 | AFFS_I(inode)->i_extcnt++; | |
170 | mark_inode_dirty(inode); | |
171 | ||
172 | return new_bh; | |
173 | } | |
174 | ||
175 | static inline struct buffer_head * | |
176 | affs_get_extblock(struct inode *inode, u32 ext) | |
177 | { | |
178 | /* inline the simplest case: same extended block as last time */ | |
179 | struct buffer_head *bh = AFFS_I(inode)->i_ext_bh; | |
180 | if (ext == AFFS_I(inode)->i_ext_last) | |
181 | atomic_inc(&bh->b_count); | |
182 | else | |
183 | /* we have to do more (not inlined) */ | |
184 | bh = affs_get_extblock_slow(inode, ext); | |
185 | ||
186 | return bh; | |
187 | } | |
188 | ||
189 | static struct buffer_head * | |
190 | affs_get_extblock_slow(struct inode *inode, u32 ext) | |
191 | { | |
192 | struct super_block *sb = inode->i_sb; | |
193 | struct buffer_head *bh; | |
194 | u32 ext_key; | |
195 | u32 lc_idx, lc_off, ac_idx; | |
196 | u32 tmp, idx; | |
197 | ||
198 | if (ext == AFFS_I(inode)->i_ext_last + 1) { | |
199 | /* read the next extended block from the current one */ | |
200 | bh = AFFS_I(inode)->i_ext_bh; | |
201 | ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); | |
202 | if (ext < AFFS_I(inode)->i_extcnt) | |
203 | goto read_ext; | |
204 | if (ext > AFFS_I(inode)->i_extcnt) | |
205 | BUG(); | |
206 | bh = affs_alloc_extblock(inode, bh, ext); | |
207 | if (IS_ERR(bh)) | |
208 | return bh; | |
209 | goto store_ext; | |
210 | } | |
211 | ||
212 | if (ext == 0) { | |
213 | /* we seek back to the file header block */ | |
214 | ext_key = inode->i_ino; | |
215 | goto read_ext; | |
216 | } | |
217 | ||
218 | if (ext >= AFFS_I(inode)->i_extcnt) { | |
219 | struct buffer_head *prev_bh; | |
220 | ||
221 | /* allocate a new extended block */ | |
222 | if (ext > AFFS_I(inode)->i_extcnt) | |
223 | BUG(); | |
224 | ||
225 | /* get previous extended block */ | |
226 | prev_bh = affs_get_extblock(inode, ext - 1); | |
227 | if (IS_ERR(prev_bh)) | |
228 | return prev_bh; | |
229 | bh = affs_alloc_extblock(inode, prev_bh, ext); | |
230 | affs_brelse(prev_bh); | |
231 | if (IS_ERR(bh)) | |
232 | return bh; | |
233 | goto store_ext; | |
234 | } | |
235 | ||
236 | again: | |
237 | /* check if there is an extended cache and whether it's large enough */ | |
238 | lc_idx = ext >> AFFS_I(inode)->i_lc_shift; | |
239 | lc_off = ext & AFFS_I(inode)->i_lc_mask; | |
240 | ||
241 | if (lc_idx >= AFFS_I(inode)->i_lc_size) { | |
242 | int err; | |
243 | ||
244 | err = affs_grow_extcache(inode, lc_idx); | |
245 | if (err) | |
246 | return ERR_PTR(err); | |
247 | goto again; | |
248 | } | |
249 | ||
250 | /* every n'th key we find in the linear cache */ | |
251 | if (!lc_off) { | |
252 | ext_key = AFFS_I(inode)->i_lc[lc_idx]; | |
253 | goto read_ext; | |
254 | } | |
255 | ||
256 | /* maybe it's still in the associative cache */ | |
257 | ac_idx = (ext - lc_idx - 1) & AFFS_AC_MASK; | |
258 | if (AFFS_I(inode)->i_ac[ac_idx].ext == ext) { | |
259 | ext_key = AFFS_I(inode)->i_ac[ac_idx].key; | |
260 | goto read_ext; | |
261 | } | |
262 | ||
263 | /* try to find one of the previous extended blocks */ | |
264 | tmp = ext; | |
265 | idx = ac_idx; | |
266 | while (--tmp, --lc_off > 0) { | |
267 | idx = (idx - 1) & AFFS_AC_MASK; | |
268 | if (AFFS_I(inode)->i_ac[idx].ext == tmp) { | |
269 | ext_key = AFFS_I(inode)->i_ac[idx].key; | |
270 | goto find_ext; | |
271 | } | |
272 | } | |
273 | ||
274 | /* fall back to the linear cache */ | |
275 | ext_key = AFFS_I(inode)->i_lc[lc_idx]; | |
276 | find_ext: | |
277 | /* read all extended blocks until we find the one we need */ | |
278 | //unlock cache | |
279 | do { | |
280 | bh = affs_bread(sb, ext_key); | |
281 | if (!bh) | |
282 | goto err_bread; | |
283 | ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); | |
284 | affs_brelse(bh); | |
285 | tmp++; | |
286 | } while (tmp < ext); | |
287 | //lock cache | |
288 | ||
289 | /* store it in the associative cache */ | |
290 | // recalculate ac_idx? | |
291 | AFFS_I(inode)->i_ac[ac_idx].ext = ext; | |
292 | AFFS_I(inode)->i_ac[ac_idx].key = ext_key; | |
293 | ||
294 | read_ext: | |
295 | /* finally read the right extended block */ | |
296 | //unlock cache | |
297 | bh = affs_bread(sb, ext_key); | |
298 | if (!bh) | |
299 | goto err_bread; | |
300 | //lock cache | |
301 | ||
302 | store_ext: | |
303 | /* release old cached extended block and store the new one */ | |
304 | affs_brelse(AFFS_I(inode)->i_ext_bh); | |
305 | AFFS_I(inode)->i_ext_last = ext; | |
306 | AFFS_I(inode)->i_ext_bh = bh; | |
307 | atomic_inc(&bh->b_count); | |
308 | ||
309 | return bh; | |
310 | ||
311 | err_bread: | |
312 | affs_brelse(bh); | |
313 | return ERR_PTR(-EIO); | |
314 | } | |
315 | ||
316 | static int | |
317 | affs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh_result, int create) | |
318 | { | |
319 | struct super_block *sb = inode->i_sb; | |
320 | struct buffer_head *ext_bh; | |
321 | u32 ext; | |
322 | ||
323 | pr_debug("AFFS: get_block(%u, %lu)\n", (u32)inode->i_ino, (unsigned long)block); | |
324 | ||
325 | ||
326 | if (block > (sector_t)0x7fffffffUL) | |
327 | BUG(); | |
328 | ||
329 | if (block >= AFFS_I(inode)->i_blkcnt) { | |
330 | if (block > AFFS_I(inode)->i_blkcnt || !create) | |
331 | goto err_big; | |
332 | } else | |
333 | create = 0; | |
334 | ||
335 | //lock cache | |
336 | affs_lock_ext(inode); | |
337 | ||
338 | ext = (u32)block / AFFS_SB(sb)->s_hashsize; | |
339 | block -= ext * AFFS_SB(sb)->s_hashsize; | |
340 | ext_bh = affs_get_extblock(inode, ext); | |
341 | if (IS_ERR(ext_bh)) | |
342 | goto err_ext; | |
343 | map_bh(bh_result, sb, (sector_t)be32_to_cpu(AFFS_BLOCK(sb, ext_bh, block))); | |
344 | ||
345 | if (create) { | |
346 | u32 blocknr = affs_alloc_block(inode, ext_bh->b_blocknr); | |
347 | if (!blocknr) | |
348 | goto err_alloc; | |
349 | set_buffer_new(bh_result); | |
350 | AFFS_I(inode)->mmu_private += AFFS_SB(sb)->s_data_blksize; | |
351 | AFFS_I(inode)->i_blkcnt++; | |
352 | ||
353 | /* store new block */ | |
354 | if (bh_result->b_blocknr) | |
355 | affs_warning(sb, "get_block", "block already set (%x)", bh_result->b_blocknr); | |
356 | AFFS_BLOCK(sb, ext_bh, block) = cpu_to_be32(blocknr); | |
357 | AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(block + 1); | |
358 | affs_adjust_checksum(ext_bh, blocknr - bh_result->b_blocknr + 1); | |
359 | bh_result->b_blocknr = blocknr; | |
360 | ||
361 | if (!block) { | |
362 | /* insert first block into header block */ | |
363 | u32 tmp = be32_to_cpu(AFFS_HEAD(ext_bh)->first_data); | |
364 | if (tmp) | |
365 | affs_warning(sb, "get_block", "first block already set (%d)", tmp); | |
366 | AFFS_HEAD(ext_bh)->first_data = cpu_to_be32(blocknr); | |
367 | affs_adjust_checksum(ext_bh, blocknr - tmp); | |
368 | } | |
369 | } | |
370 | ||
371 | affs_brelse(ext_bh); | |
372 | //unlock cache | |
373 | affs_unlock_ext(inode); | |
374 | return 0; | |
375 | ||
376 | err_big: | |
377 | affs_error(inode->i_sb,"get_block","strange block request %d", block); | |
378 | return -EIO; | |
379 | err_ext: | |
380 | // unlock cache | |
381 | affs_unlock_ext(inode); | |
382 | return PTR_ERR(ext_bh); | |
383 | err_alloc: | |
384 | brelse(ext_bh); | |
385 | clear_buffer_mapped(bh_result); | |
386 | bh_result->b_bdev = NULL; | |
387 | // unlock cache | |
388 | affs_unlock_ext(inode); | |
389 | return -ENOSPC; | |
390 | } | |
391 | ||
392 | static int affs_writepage(struct page *page, struct writeback_control *wbc) | |
393 | { | |
394 | return block_write_full_page(page, affs_get_block, wbc); | |
395 | } | |
396 | static int affs_readpage(struct file *file, struct page *page) | |
397 | { | |
398 | return block_read_full_page(page, affs_get_block); | |
399 | } | |
400 | static int affs_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to) | |
401 | { | |
402 | return cont_prepare_write(page, from, to, affs_get_block, | |
403 | &AFFS_I(page->mapping->host)->mmu_private); | |
404 | } | |
405 | static sector_t _affs_bmap(struct address_space *mapping, sector_t block) | |
406 | { | |
407 | return generic_block_bmap(mapping,block,affs_get_block); | |
408 | } | |
409 | struct address_space_operations affs_aops = { | |
410 | .readpage = affs_readpage, | |
411 | .writepage = affs_writepage, | |
412 | .sync_page = block_sync_page, | |
413 | .prepare_write = affs_prepare_write, | |
414 | .commit_write = generic_commit_write, | |
415 | .bmap = _affs_bmap | |
416 | }; | |
417 | ||
418 | static inline struct buffer_head * | |
419 | affs_bread_ino(struct inode *inode, int block, int create) | |
420 | { | |
421 | struct buffer_head *bh, tmp_bh; | |
422 | int err; | |
423 | ||
424 | tmp_bh.b_state = 0; | |
425 | err = affs_get_block(inode, block, &tmp_bh, create); | |
426 | if (!err) { | |
427 | bh = affs_bread(inode->i_sb, tmp_bh.b_blocknr); | |
428 | if (bh) { | |
429 | bh->b_state |= tmp_bh.b_state; | |
430 | return bh; | |
431 | } | |
432 | err = -EIO; | |
433 | } | |
434 | return ERR_PTR(err); | |
435 | } | |
436 | ||
437 | static inline struct buffer_head * | |
438 | affs_getzeroblk_ino(struct inode *inode, int block) | |
439 | { | |
440 | struct buffer_head *bh, tmp_bh; | |
441 | int err; | |
442 | ||
443 | tmp_bh.b_state = 0; | |
444 | err = affs_get_block(inode, block, &tmp_bh, 1); | |
445 | if (!err) { | |
446 | bh = affs_getzeroblk(inode->i_sb, tmp_bh.b_blocknr); | |
447 | if (bh) { | |
448 | bh->b_state |= tmp_bh.b_state; | |
449 | return bh; | |
450 | } | |
451 | err = -EIO; | |
452 | } | |
453 | return ERR_PTR(err); | |
454 | } | |
455 | ||
456 | static inline struct buffer_head * | |
457 | affs_getemptyblk_ino(struct inode *inode, int block) | |
458 | { | |
459 | struct buffer_head *bh, tmp_bh; | |
460 | int err; | |
461 | ||
462 | tmp_bh.b_state = 0; | |
463 | err = affs_get_block(inode, block, &tmp_bh, 1); | |
464 | if (!err) { | |
465 | bh = affs_getemptyblk(inode->i_sb, tmp_bh.b_blocknr); | |
466 | if (bh) { | |
467 | bh->b_state |= tmp_bh.b_state; | |
468 | return bh; | |
469 | } | |
470 | err = -EIO; | |
471 | } | |
472 | return ERR_PTR(err); | |
473 | } | |
474 | ||
1da177e4 LT |
475 | static int |
476 | affs_do_readpage_ofs(struct file *file, struct page *page, unsigned from, unsigned to) | |
477 | { | |
478 | struct inode *inode = page->mapping->host; | |
479 | struct super_block *sb = inode->i_sb; | |
480 | struct buffer_head *bh; | |
481 | char *data; | |
482 | u32 bidx, boff, bsize; | |
483 | u32 tmp; | |
484 | ||
485 | pr_debug("AFFS: read_page(%u, %ld, %d, %d)\n", (u32)inode->i_ino, page->index, from, to); | |
486 | if (from > to || to > PAGE_CACHE_SIZE) | |
487 | BUG(); | |
488 | kmap(page); | |
489 | data = page_address(page); | |
490 | bsize = AFFS_SB(sb)->s_data_blksize; | |
491 | tmp = (page->index << PAGE_CACHE_SHIFT) + from; | |
492 | bidx = tmp / bsize; | |
493 | boff = tmp % bsize; | |
494 | ||
495 | while (from < to) { | |
496 | bh = affs_bread_ino(inode, bidx, 0); | |
497 | if (IS_ERR(bh)) | |
498 | return PTR_ERR(bh); | |
499 | tmp = min(bsize - boff, to - from); | |
500 | if (from + tmp > to || tmp > bsize) | |
501 | BUG(); | |
502 | memcpy(data + from, AFFS_DATA(bh) + boff, tmp); | |
503 | affs_brelse(bh); | |
504 | bidx++; | |
505 | from += tmp; | |
506 | boff = 0; | |
507 | } | |
508 | flush_dcache_page(page); | |
509 | kunmap(page); | |
510 | return 0; | |
511 | } | |
512 | ||
513 | static int | |
514 | affs_extent_file_ofs(struct inode *inode, u32 newsize) | |
515 | { | |
516 | struct super_block *sb = inode->i_sb; | |
517 | struct buffer_head *bh, *prev_bh; | |
518 | u32 bidx, boff; | |
519 | u32 size, bsize; | |
520 | u32 tmp; | |
521 | ||
522 | pr_debug("AFFS: extent_file(%u, %d)\n", (u32)inode->i_ino, newsize); | |
523 | bsize = AFFS_SB(sb)->s_data_blksize; | |
524 | bh = NULL; | |
525 | size = AFFS_I(inode)->mmu_private; | |
526 | bidx = size / bsize; | |
527 | boff = size % bsize; | |
528 | if (boff) { | |
529 | bh = affs_bread_ino(inode, bidx, 0); | |
530 | if (IS_ERR(bh)) | |
531 | return PTR_ERR(bh); | |
532 | tmp = min(bsize - boff, newsize - size); | |
533 | if (boff + tmp > bsize || tmp > bsize) | |
534 | BUG(); | |
535 | memset(AFFS_DATA(bh) + boff, 0, tmp); | |
536 | AFFS_DATA_HEAD(bh)->size = cpu_to_be32(be32_to_cpu(AFFS_DATA_HEAD(bh)->size) + tmp); | |
537 | affs_fix_checksum(sb, bh); | |
538 | mark_buffer_dirty_inode(bh, inode); | |
539 | size += tmp; | |
540 | bidx++; | |
541 | } else if (bidx) { | |
542 | bh = affs_bread_ino(inode, bidx - 1, 0); | |
543 | if (IS_ERR(bh)) | |
544 | return PTR_ERR(bh); | |
545 | } | |
546 | ||
547 | while (size < newsize) { | |
548 | prev_bh = bh; | |
549 | bh = affs_getzeroblk_ino(inode, bidx); | |
550 | if (IS_ERR(bh)) | |
551 | goto out; | |
552 | tmp = min(bsize, newsize - size); | |
553 | if (tmp > bsize) | |
554 | BUG(); | |
555 | AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); | |
556 | AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); | |
557 | AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); | |
558 | AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); | |
559 | affs_fix_checksum(sb, bh); | |
560 | bh->b_state &= ~(1UL << BH_New); | |
561 | mark_buffer_dirty_inode(bh, inode); | |
562 | if (prev_bh) { | |
563 | u32 tmp = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); | |
564 | if (tmp) | |
565 | affs_warning(sb, "extent_file_ofs", "next block already set for %d (%d)", bidx, tmp); | |
566 | AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); | |
567 | affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp); | |
568 | mark_buffer_dirty_inode(prev_bh, inode); | |
569 | affs_brelse(prev_bh); | |
570 | } | |
571 | size += bsize; | |
572 | bidx++; | |
573 | } | |
574 | affs_brelse(bh); | |
575 | inode->i_size = AFFS_I(inode)->mmu_private = newsize; | |
576 | return 0; | |
577 | ||
578 | out: | |
579 | inode->i_size = AFFS_I(inode)->mmu_private = newsize; | |
580 | return PTR_ERR(bh); | |
581 | } | |
582 | ||
583 | static int | |
584 | affs_readpage_ofs(struct file *file, struct page *page) | |
585 | { | |
586 | struct inode *inode = page->mapping->host; | |
587 | u32 to; | |
588 | int err; | |
589 | ||
590 | pr_debug("AFFS: read_page(%u, %ld)\n", (u32)inode->i_ino, page->index); | |
591 | to = PAGE_CACHE_SIZE; | |
592 | if (((page->index + 1) << PAGE_CACHE_SHIFT) > inode->i_size) { | |
593 | to = inode->i_size & ~PAGE_CACHE_MASK; | |
594 | memset(page_address(page) + to, 0, PAGE_CACHE_SIZE - to); | |
595 | } | |
596 | ||
597 | err = affs_do_readpage_ofs(file, page, 0, to); | |
598 | if (!err) | |
599 | SetPageUptodate(page); | |
600 | unlock_page(page); | |
601 | return err; | |
602 | } | |
603 | ||
604 | static int affs_prepare_write_ofs(struct file *file, struct page *page, unsigned from, unsigned to) | |
605 | { | |
606 | struct inode *inode = page->mapping->host; | |
607 | u32 size, offset; | |
608 | u32 tmp; | |
609 | int err = 0; | |
610 | ||
611 | pr_debug("AFFS: prepare_write(%u, %ld, %d, %d)\n", (u32)inode->i_ino, page->index, from, to); | |
612 | offset = page->index << PAGE_CACHE_SHIFT; | |
613 | if (offset + from > AFFS_I(inode)->mmu_private) { | |
614 | err = affs_extent_file_ofs(inode, offset + from); | |
615 | if (err) | |
616 | return err; | |
617 | } | |
618 | size = inode->i_size; | |
619 | ||
620 | if (PageUptodate(page)) | |
621 | return 0; | |
622 | ||
623 | if (from) { | |
624 | err = affs_do_readpage_ofs(file, page, 0, from); | |
625 | if (err) | |
626 | return err; | |
627 | } | |
628 | if (to < PAGE_CACHE_SIZE) { | |
629 | char *kaddr = kmap_atomic(page, KM_USER0); | |
630 | ||
631 | memset(kaddr + to, 0, PAGE_CACHE_SIZE - to); | |
632 | flush_dcache_page(page); | |
633 | kunmap_atomic(kaddr, KM_USER0); | |
634 | if (size > offset + to) { | |
635 | if (size < offset + PAGE_CACHE_SIZE) | |
636 | tmp = size & ~PAGE_CACHE_MASK; | |
637 | else | |
638 | tmp = PAGE_CACHE_SIZE; | |
639 | err = affs_do_readpage_ofs(file, page, to, tmp); | |
640 | } | |
641 | } | |
642 | return err; | |
643 | } | |
644 | ||
645 | static int affs_commit_write_ofs(struct file *file, struct page *page, unsigned from, unsigned to) | |
646 | { | |
647 | struct inode *inode = page->mapping->host; | |
648 | struct super_block *sb = inode->i_sb; | |
649 | struct buffer_head *bh, *prev_bh; | |
650 | char *data; | |
651 | u32 bidx, boff, bsize; | |
652 | u32 tmp; | |
653 | int written; | |
654 | ||
655 | pr_debug("AFFS: commit_write(%u, %ld, %d, %d)\n", (u32)inode->i_ino, page->index, from, to); | |
656 | bsize = AFFS_SB(sb)->s_data_blksize; | |
657 | data = page_address(page); | |
658 | ||
659 | bh = NULL; | |
660 | written = 0; | |
661 | tmp = (page->index << PAGE_CACHE_SHIFT) + from; | |
662 | bidx = tmp / bsize; | |
663 | boff = tmp % bsize; | |
664 | if (boff) { | |
665 | bh = affs_bread_ino(inode, bidx, 0); | |
666 | if (IS_ERR(bh)) | |
667 | return PTR_ERR(bh); | |
668 | tmp = min(bsize - boff, to - from); | |
669 | if (boff + tmp > bsize || tmp > bsize) | |
670 | BUG(); | |
671 | memcpy(AFFS_DATA(bh) + boff, data + from, tmp); | |
672 | AFFS_DATA_HEAD(bh)->size = cpu_to_be32(be32_to_cpu(AFFS_DATA_HEAD(bh)->size) + tmp); | |
673 | affs_fix_checksum(sb, bh); | |
674 | mark_buffer_dirty_inode(bh, inode); | |
675 | written += tmp; | |
676 | from += tmp; | |
677 | bidx++; | |
678 | } else if (bidx) { | |
679 | bh = affs_bread_ino(inode, bidx - 1, 0); | |
680 | if (IS_ERR(bh)) | |
681 | return PTR_ERR(bh); | |
682 | } | |
683 | while (from + bsize <= to) { | |
684 | prev_bh = bh; | |
685 | bh = affs_getemptyblk_ino(inode, bidx); | |
686 | if (IS_ERR(bh)) | |
687 | goto out; | |
688 | memcpy(AFFS_DATA(bh), data + from, bsize); | |
689 | if (buffer_new(bh)) { | |
690 | AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); | |
691 | AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); | |
692 | AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); | |
693 | AFFS_DATA_HEAD(bh)->size = cpu_to_be32(bsize); | |
694 | AFFS_DATA_HEAD(bh)->next = 0; | |
695 | bh->b_state &= ~(1UL << BH_New); | |
696 | if (prev_bh) { | |
697 | u32 tmp = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); | |
698 | if (tmp) | |
699 | affs_warning(sb, "commit_write_ofs", "next block already set for %d (%d)", bidx, tmp); | |
700 | AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); | |
701 | affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp); | |
702 | mark_buffer_dirty_inode(prev_bh, inode); | |
703 | } | |
704 | } | |
705 | affs_brelse(prev_bh); | |
706 | affs_fix_checksum(sb, bh); | |
707 | mark_buffer_dirty_inode(bh, inode); | |
708 | written += bsize; | |
709 | from += bsize; | |
710 | bidx++; | |
711 | } | |
712 | if (from < to) { | |
713 | prev_bh = bh; | |
714 | bh = affs_bread_ino(inode, bidx, 1); | |
715 | if (IS_ERR(bh)) | |
716 | goto out; | |
717 | tmp = min(bsize, to - from); | |
718 | if (tmp > bsize) | |
719 | BUG(); | |
720 | memcpy(AFFS_DATA(bh), data + from, tmp); | |
721 | if (buffer_new(bh)) { | |
722 | AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); | |
723 | AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); | |
724 | AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); | |
725 | AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); | |
726 | AFFS_DATA_HEAD(bh)->next = 0; | |
727 | bh->b_state &= ~(1UL << BH_New); | |
728 | if (prev_bh) { | |
729 | u32 tmp = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); | |
730 | if (tmp) | |
731 | affs_warning(sb, "commit_write_ofs", "next block already set for %d (%d)", bidx, tmp); | |
732 | AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); | |
733 | affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp); | |
734 | mark_buffer_dirty_inode(prev_bh, inode); | |
735 | } | |
736 | } else if (be32_to_cpu(AFFS_DATA_HEAD(bh)->size) < tmp) | |
737 | AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); | |
738 | affs_brelse(prev_bh); | |
739 | affs_fix_checksum(sb, bh); | |
740 | mark_buffer_dirty_inode(bh, inode); | |
741 | written += tmp; | |
742 | from += tmp; | |
743 | bidx++; | |
744 | } | |
745 | SetPageUptodate(page); | |
746 | ||
747 | done: | |
748 | affs_brelse(bh); | |
749 | tmp = (page->index << PAGE_CACHE_SHIFT) + from; | |
750 | if (tmp > inode->i_size) | |
751 | inode->i_size = AFFS_I(inode)->mmu_private = tmp; | |
752 | ||
753 | return written; | |
754 | ||
755 | out: | |
756 | bh = prev_bh; | |
757 | if (!written) | |
758 | written = PTR_ERR(bh); | |
759 | goto done; | |
760 | } | |
761 | ||
762 | struct address_space_operations affs_aops_ofs = { | |
763 | .readpage = affs_readpage_ofs, | |
764 | //.writepage = affs_writepage_ofs, | |
765 | //.sync_page = affs_sync_page_ofs, | |
766 | .prepare_write = affs_prepare_write_ofs, | |
767 | .commit_write = affs_commit_write_ofs | |
768 | }; | |
769 | ||
770 | /* Free any preallocated blocks. */ | |
771 | ||
772 | void | |
773 | affs_free_prealloc(struct inode *inode) | |
774 | { | |
775 | struct super_block *sb = inode->i_sb; | |
776 | ||
777 | pr_debug("AFFS: free_prealloc(ino=%lu)\n", inode->i_ino); | |
778 | ||
779 | while (AFFS_I(inode)->i_pa_cnt) { | |
780 | AFFS_I(inode)->i_pa_cnt--; | |
781 | affs_free_block(sb, ++AFFS_I(inode)->i_lastalloc); | |
782 | } | |
783 | } | |
784 | ||
785 | /* Truncate (or enlarge) a file to the requested size. */ | |
786 | ||
787 | void | |
788 | affs_truncate(struct inode *inode) | |
789 | { | |
790 | struct super_block *sb = inode->i_sb; | |
791 | u32 ext, ext_key; | |
792 | u32 last_blk, blkcnt, blk; | |
793 | u32 size; | |
794 | struct buffer_head *ext_bh; | |
795 | int i; | |
796 | ||
797 | pr_debug("AFFS: truncate(inode=%d, oldsize=%u, newsize=%u)\n", | |
798 | (u32)inode->i_ino, (u32)AFFS_I(inode)->mmu_private, (u32)inode->i_size); | |
799 | ||
800 | last_blk = 0; | |
801 | ext = 0; | |
802 | if (inode->i_size) { | |
803 | last_blk = ((u32)inode->i_size - 1) / AFFS_SB(sb)->s_data_blksize; | |
804 | ext = last_blk / AFFS_SB(sb)->s_hashsize; | |
805 | } | |
806 | ||
807 | if (inode->i_size > AFFS_I(inode)->mmu_private) { | |
808 | struct address_space *mapping = inode->i_mapping; | |
809 | struct page *page; | |
810 | u32 size = inode->i_size - 1; | |
811 | int res; | |
812 | ||
813 | page = grab_cache_page(mapping, size >> PAGE_CACHE_SHIFT); | |
814 | if (!page) | |
815 | return; | |
816 | size = (size & (PAGE_CACHE_SIZE - 1)) + 1; | |
817 | res = mapping->a_ops->prepare_write(NULL, page, size, size); | |
818 | if (!res) | |
819 | res = mapping->a_ops->commit_write(NULL, page, size, size); | |
820 | unlock_page(page); | |
821 | page_cache_release(page); | |
822 | mark_inode_dirty(inode); | |
823 | return; | |
824 | } else if (inode->i_size == AFFS_I(inode)->mmu_private) | |
825 | return; | |
826 | ||
827 | // lock cache | |
828 | ext_bh = affs_get_extblock(inode, ext); | |
829 | if (IS_ERR(ext_bh)) { | |
830 | affs_warning(sb, "truncate", "unexpected read error for ext block %u (%d)", | |
831 | ext, PTR_ERR(ext_bh)); | |
832 | return; | |
833 | } | |
834 | if (AFFS_I(inode)->i_lc) { | |
835 | /* clear linear cache */ | |
836 | i = (ext + 1) >> AFFS_I(inode)->i_lc_shift; | |
837 | if (AFFS_I(inode)->i_lc_size > i) { | |
838 | AFFS_I(inode)->i_lc_size = i; | |
839 | for (; i < AFFS_LC_SIZE; i++) | |
840 | AFFS_I(inode)->i_lc[i] = 0; | |
841 | } | |
842 | /* clear associative cache */ | |
843 | for (i = 0; i < AFFS_AC_SIZE; i++) | |
844 | if (AFFS_I(inode)->i_ac[i].ext >= ext) | |
845 | AFFS_I(inode)->i_ac[i].ext = 0; | |
846 | } | |
847 | ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension); | |
848 | ||
849 | blkcnt = AFFS_I(inode)->i_blkcnt; | |
850 | i = 0; | |
851 | blk = last_blk; | |
852 | if (inode->i_size) { | |
853 | i = last_blk % AFFS_SB(sb)->s_hashsize + 1; | |
854 | blk++; | |
855 | } else | |
856 | AFFS_HEAD(ext_bh)->first_data = 0; | |
857 | size = AFFS_SB(sb)->s_hashsize; | |
858 | if (size > blkcnt - blk + i) | |
859 | size = blkcnt - blk + i; | |
860 | for (; i < size; i++, blk++) { | |
861 | affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i))); | |
862 | AFFS_BLOCK(sb, ext_bh, i) = 0; | |
863 | } | |
864 | AFFS_TAIL(sb, ext_bh)->extension = 0; | |
865 | affs_fix_checksum(sb, ext_bh); | |
866 | mark_buffer_dirty_inode(ext_bh, inode); | |
867 | affs_brelse(ext_bh); | |
868 | ||
869 | if (inode->i_size) { | |
870 | AFFS_I(inode)->i_blkcnt = last_blk + 1; | |
871 | AFFS_I(inode)->i_extcnt = ext + 1; | |
872 | if (AFFS_SB(sb)->s_flags & SF_OFS) { | |
873 | struct buffer_head *bh = affs_bread_ino(inode, last_blk, 0); | |
874 | u32 tmp; | |
875 | if (IS_ERR(ext_bh)) { | |
876 | affs_warning(sb, "truncate", "unexpected read error for last block %u (%d)", | |
877 | ext, PTR_ERR(ext_bh)); | |
878 | return; | |
879 | } | |
880 | tmp = be32_to_cpu(AFFS_DATA_HEAD(bh)->next); | |
881 | AFFS_DATA_HEAD(bh)->next = 0; | |
882 | affs_adjust_checksum(bh, -tmp); | |
883 | affs_brelse(bh); | |
884 | } | |
885 | } else { | |
886 | AFFS_I(inode)->i_blkcnt = 0; | |
887 | AFFS_I(inode)->i_extcnt = 1; | |
888 | } | |
889 | AFFS_I(inode)->mmu_private = inode->i_size; | |
890 | // unlock cache | |
891 | ||
892 | while (ext_key) { | |
893 | ext_bh = affs_bread(sb, ext_key); | |
894 | size = AFFS_SB(sb)->s_hashsize; | |
895 | if (size > blkcnt - blk) | |
896 | size = blkcnt - blk; | |
897 | for (i = 0; i < size; i++, blk++) | |
898 | affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i))); | |
899 | affs_free_block(sb, ext_key); | |
900 | ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension); | |
901 | affs_brelse(ext_bh); | |
902 | } | |
903 | affs_free_prealloc(inode); | |
904 | } |