Commit | Line | Data |
---|---|---|
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 | 29 | .llseek = generic_file_llseek, |
543ade1f BP |
30 | .read = do_sync_read, |
31 | .aio_read = generic_file_aio_read, | |
32 | .write = do_sync_write, | |
33 | .aio_write = generic_file_aio_write, | |
1da177e4 LT |
34 | .mmap = generic_file_mmap, |
35 | .open = affs_file_open, | |
36 | .release = affs_file_release, | |
37 | .fsync = file_fsync, | |
5ffc4ef4 | 38 | .splice_read = generic_file_splice_read, |
1da177e4 LT |
39 | }; |
40 | ||
754661f1 | 41 | const struct inode_operations affs_file_inode_operations = { |
1da177e4 LT |
42 | .truncate = affs_truncate, |
43 | .setattr = affs_notify_change, | |
44 | }; | |
45 | ||
46 | static int | |
47 | affs_file_open(struct inode *inode, struct file *filp) | |
48 | { | |
49 | if (atomic_read(&filp->f_count) != 1) | |
50 | return 0; | |
51 | pr_debug("AFFS: open(%d)\n", AFFS_I(inode)->i_opencnt); | |
52 | AFFS_I(inode)->i_opencnt++; | |
53 | return 0; | |
54 | } | |
55 | ||
56 | static int | |
57 | affs_file_release(struct inode *inode, struct file *filp) | |
58 | { | |
59 | if (atomic_read(&filp->f_count) != 0) | |
60 | return 0; | |
61 | pr_debug("AFFS: release(%d)\n", AFFS_I(inode)->i_opencnt); | |
62 | AFFS_I(inode)->i_opencnt--; | |
63 | if (!AFFS_I(inode)->i_opencnt) | |
64 | affs_free_prealloc(inode); | |
65 | ||
66 | return 0; | |
67 | } | |
68 | ||
69 | static int | |
70 | affs_grow_extcache(struct inode *inode, u32 lc_idx) | |
71 | { | |
72 | struct super_block *sb = inode->i_sb; | |
73 | struct buffer_head *bh; | |
74 | u32 lc_max; | |
75 | int i, j, key; | |
76 | ||
77 | if (!AFFS_I(inode)->i_lc) { | |
78 | char *ptr = (char *)get_zeroed_page(GFP_NOFS); | |
79 | if (!ptr) | |
80 | return -ENOMEM; | |
81 | AFFS_I(inode)->i_lc = (u32 *)ptr; | |
82 | AFFS_I(inode)->i_ac = (struct affs_ext_key *)(ptr + AFFS_CACHE_SIZE / 2); | |
83 | } | |
84 | ||
85 | lc_max = AFFS_LC_SIZE << AFFS_I(inode)->i_lc_shift; | |
86 | ||
87 | if (AFFS_I(inode)->i_extcnt > lc_max) { | |
88 | u32 lc_shift, lc_mask, tmp, off; | |
89 | ||
90 | /* need to recalculate linear cache, start from old size */ | |
91 | lc_shift = AFFS_I(inode)->i_lc_shift; | |
92 | tmp = (AFFS_I(inode)->i_extcnt / AFFS_LC_SIZE) >> lc_shift; | |
93 | for (; tmp; tmp >>= 1) | |
94 | lc_shift++; | |
95 | lc_mask = (1 << lc_shift) - 1; | |
96 | ||
97 | /* fix idx and old size to new shift */ | |
98 | lc_idx >>= (lc_shift - AFFS_I(inode)->i_lc_shift); | |
99 | AFFS_I(inode)->i_lc_size >>= (lc_shift - AFFS_I(inode)->i_lc_shift); | |
100 | ||
101 | /* first shrink old cache to make more space */ | |
102 | off = 1 << (lc_shift - AFFS_I(inode)->i_lc_shift); | |
103 | for (i = 1, j = off; j < AFFS_LC_SIZE; i++, j += off) | |
104 | AFFS_I(inode)->i_ac[i] = AFFS_I(inode)->i_ac[j]; | |
105 | ||
106 | AFFS_I(inode)->i_lc_shift = lc_shift; | |
107 | AFFS_I(inode)->i_lc_mask = lc_mask; | |
108 | } | |
109 | ||
110 | /* fill cache to the needed index */ | |
111 | i = AFFS_I(inode)->i_lc_size; | |
112 | AFFS_I(inode)->i_lc_size = lc_idx + 1; | |
113 | for (; i <= lc_idx; i++) { | |
114 | if (!i) { | |
115 | AFFS_I(inode)->i_lc[0] = inode->i_ino; | |
116 | continue; | |
117 | } | |
118 | key = AFFS_I(inode)->i_lc[i - 1]; | |
119 | j = AFFS_I(inode)->i_lc_mask + 1; | |
120 | // unlock cache | |
121 | for (; j > 0; j--) { | |
122 | bh = affs_bread(sb, key); | |
123 | if (!bh) | |
124 | goto err; | |
125 | key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); | |
126 | affs_brelse(bh); | |
127 | } | |
128 | // lock cache | |
129 | AFFS_I(inode)->i_lc[i] = key; | |
130 | } | |
131 | ||
132 | return 0; | |
133 | ||
134 | err: | |
135 | // lock cache | |
136 | return -EIO; | |
137 | } | |
138 | ||
139 | static struct buffer_head * | |
140 | affs_alloc_extblock(struct inode *inode, struct buffer_head *bh, u32 ext) | |
141 | { | |
142 | struct super_block *sb = inode->i_sb; | |
143 | struct buffer_head *new_bh; | |
144 | u32 blocknr, tmp; | |
145 | ||
146 | blocknr = affs_alloc_block(inode, bh->b_blocknr); | |
147 | if (!blocknr) | |
148 | return ERR_PTR(-ENOSPC); | |
149 | ||
150 | new_bh = affs_getzeroblk(sb, blocknr); | |
151 | if (!new_bh) { | |
152 | affs_free_block(sb, blocknr); | |
153 | return ERR_PTR(-EIO); | |
154 | } | |
155 | ||
156 | AFFS_HEAD(new_bh)->ptype = cpu_to_be32(T_LIST); | |
157 | AFFS_HEAD(new_bh)->key = cpu_to_be32(blocknr); | |
158 | AFFS_TAIL(sb, new_bh)->stype = cpu_to_be32(ST_FILE); | |
159 | AFFS_TAIL(sb, new_bh)->parent = cpu_to_be32(inode->i_ino); | |
160 | affs_fix_checksum(sb, new_bh); | |
161 | ||
162 | mark_buffer_dirty_inode(new_bh, inode); | |
163 | ||
164 | tmp = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); | |
165 | if (tmp) | |
166 | affs_warning(sb, "alloc_ext", "previous extension set (%x)", tmp); | |
167 | AFFS_TAIL(sb, bh)->extension = cpu_to_be32(blocknr); | |
168 | affs_adjust_checksum(bh, blocknr - tmp); | |
169 | mark_buffer_dirty_inode(bh, inode); | |
170 | ||
171 | AFFS_I(inode)->i_extcnt++; | |
172 | mark_inode_dirty(inode); | |
173 | ||
174 | return new_bh; | |
175 | } | |
176 | ||
177 | static inline struct buffer_head * | |
178 | affs_get_extblock(struct inode *inode, u32 ext) | |
179 | { | |
180 | /* inline the simplest case: same extended block as last time */ | |
181 | struct buffer_head *bh = AFFS_I(inode)->i_ext_bh; | |
182 | if (ext == AFFS_I(inode)->i_ext_last) | |
183 | atomic_inc(&bh->b_count); | |
184 | else | |
185 | /* we have to do more (not inlined) */ | |
186 | bh = affs_get_extblock_slow(inode, ext); | |
187 | ||
188 | return bh; | |
189 | } | |
190 | ||
191 | static struct buffer_head * | |
192 | affs_get_extblock_slow(struct inode *inode, u32 ext) | |
193 | { | |
194 | struct super_block *sb = inode->i_sb; | |
195 | struct buffer_head *bh; | |
196 | u32 ext_key; | |
197 | u32 lc_idx, lc_off, ac_idx; | |
198 | u32 tmp, idx; | |
199 | ||
200 | if (ext == AFFS_I(inode)->i_ext_last + 1) { | |
201 | /* read the next extended block from the current one */ | |
202 | bh = AFFS_I(inode)->i_ext_bh; | |
203 | ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); | |
204 | if (ext < AFFS_I(inode)->i_extcnt) | |
205 | goto read_ext; | |
206 | if (ext > AFFS_I(inode)->i_extcnt) | |
207 | BUG(); | |
208 | bh = affs_alloc_extblock(inode, bh, ext); | |
209 | if (IS_ERR(bh)) | |
210 | return bh; | |
211 | goto store_ext; | |
212 | } | |
213 | ||
214 | if (ext == 0) { | |
215 | /* we seek back to the file header block */ | |
216 | ext_key = inode->i_ino; | |
217 | goto read_ext; | |
218 | } | |
219 | ||
220 | if (ext >= AFFS_I(inode)->i_extcnt) { | |
221 | struct buffer_head *prev_bh; | |
222 | ||
223 | /* allocate a new extended block */ | |
224 | if (ext > AFFS_I(inode)->i_extcnt) | |
225 | BUG(); | |
226 | ||
227 | /* get previous extended block */ | |
228 | prev_bh = affs_get_extblock(inode, ext - 1); | |
229 | if (IS_ERR(prev_bh)) | |
230 | return prev_bh; | |
231 | bh = affs_alloc_extblock(inode, prev_bh, ext); | |
232 | affs_brelse(prev_bh); | |
233 | if (IS_ERR(bh)) | |
234 | return bh; | |
235 | goto store_ext; | |
236 | } | |
237 | ||
238 | again: | |
239 | /* check if there is an extended cache and whether it's large enough */ | |
240 | lc_idx = ext >> AFFS_I(inode)->i_lc_shift; | |
241 | lc_off = ext & AFFS_I(inode)->i_lc_mask; | |
242 | ||
243 | if (lc_idx >= AFFS_I(inode)->i_lc_size) { | |
244 | int err; | |
245 | ||
246 | err = affs_grow_extcache(inode, lc_idx); | |
247 | if (err) | |
248 | return ERR_PTR(err); | |
249 | goto again; | |
250 | } | |
251 | ||
252 | /* every n'th key we find in the linear cache */ | |
253 | if (!lc_off) { | |
254 | ext_key = AFFS_I(inode)->i_lc[lc_idx]; | |
255 | goto read_ext; | |
256 | } | |
257 | ||
258 | /* maybe it's still in the associative cache */ | |
259 | ac_idx = (ext - lc_idx - 1) & AFFS_AC_MASK; | |
260 | if (AFFS_I(inode)->i_ac[ac_idx].ext == ext) { | |
261 | ext_key = AFFS_I(inode)->i_ac[ac_idx].key; | |
262 | goto read_ext; | |
263 | } | |
264 | ||
265 | /* try to find one of the previous extended blocks */ | |
266 | tmp = ext; | |
267 | idx = ac_idx; | |
268 | while (--tmp, --lc_off > 0) { | |
269 | idx = (idx - 1) & AFFS_AC_MASK; | |
270 | if (AFFS_I(inode)->i_ac[idx].ext == tmp) { | |
271 | ext_key = AFFS_I(inode)->i_ac[idx].key; | |
272 | goto find_ext; | |
273 | } | |
274 | } | |
275 | ||
276 | /* fall back to the linear cache */ | |
277 | ext_key = AFFS_I(inode)->i_lc[lc_idx]; | |
278 | find_ext: | |
279 | /* read all extended blocks until we find the one we need */ | |
280 | //unlock cache | |
281 | do { | |
282 | bh = affs_bread(sb, ext_key); | |
283 | if (!bh) | |
284 | goto err_bread; | |
285 | ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); | |
286 | affs_brelse(bh); | |
287 | tmp++; | |
288 | } while (tmp < ext); | |
289 | //lock cache | |
290 | ||
291 | /* store it in the associative cache */ | |
292 | // recalculate ac_idx? | |
293 | AFFS_I(inode)->i_ac[ac_idx].ext = ext; | |
294 | AFFS_I(inode)->i_ac[ac_idx].key = ext_key; | |
295 | ||
296 | read_ext: | |
297 | /* finally read the right extended block */ | |
298 | //unlock cache | |
299 | bh = affs_bread(sb, ext_key); | |
300 | if (!bh) | |
301 | goto err_bread; | |
302 | //lock cache | |
303 | ||
304 | store_ext: | |
305 | /* release old cached extended block and store the new one */ | |
306 | affs_brelse(AFFS_I(inode)->i_ext_bh); | |
307 | AFFS_I(inode)->i_ext_last = ext; | |
308 | AFFS_I(inode)->i_ext_bh = bh; | |
309 | atomic_inc(&bh->b_count); | |
310 | ||
311 | return bh; | |
312 | ||
313 | err_bread: | |
314 | affs_brelse(bh); | |
315 | return ERR_PTR(-EIO); | |
316 | } | |
317 | ||
318 | static int | |
319 | affs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh_result, int create) | |
320 | { | |
321 | struct super_block *sb = inode->i_sb; | |
322 | struct buffer_head *ext_bh; | |
323 | u32 ext; | |
324 | ||
325 | pr_debug("AFFS: get_block(%u, %lu)\n", (u32)inode->i_ino, (unsigned long)block); | |
326 | ||
327 | ||
328 | if (block > (sector_t)0x7fffffffUL) | |
329 | BUG(); | |
330 | ||
331 | if (block >= AFFS_I(inode)->i_blkcnt) { | |
332 | if (block > AFFS_I(inode)->i_blkcnt || !create) | |
333 | goto err_big; | |
334 | } else | |
335 | create = 0; | |
336 | ||
337 | //lock cache | |
338 | affs_lock_ext(inode); | |
339 | ||
340 | ext = (u32)block / AFFS_SB(sb)->s_hashsize; | |
341 | block -= ext * AFFS_SB(sb)->s_hashsize; | |
342 | ext_bh = affs_get_extblock(inode, ext); | |
343 | if (IS_ERR(ext_bh)) | |
344 | goto err_ext; | |
345 | map_bh(bh_result, sb, (sector_t)be32_to_cpu(AFFS_BLOCK(sb, ext_bh, block))); | |
346 | ||
347 | if (create) { | |
348 | u32 blocknr = affs_alloc_block(inode, ext_bh->b_blocknr); | |
349 | if (!blocknr) | |
350 | goto err_alloc; | |
351 | set_buffer_new(bh_result); | |
352 | AFFS_I(inode)->mmu_private += AFFS_SB(sb)->s_data_blksize; | |
353 | AFFS_I(inode)->i_blkcnt++; | |
354 | ||
355 | /* store new block */ | |
356 | if (bh_result->b_blocknr) | |
357 | affs_warning(sb, "get_block", "block already set (%x)", bh_result->b_blocknr); | |
358 | AFFS_BLOCK(sb, ext_bh, block) = cpu_to_be32(blocknr); | |
359 | AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(block + 1); | |
360 | affs_adjust_checksum(ext_bh, blocknr - bh_result->b_blocknr + 1); | |
361 | bh_result->b_blocknr = blocknr; | |
362 | ||
363 | if (!block) { | |
364 | /* insert first block into header block */ | |
365 | u32 tmp = be32_to_cpu(AFFS_HEAD(ext_bh)->first_data); | |
366 | if (tmp) | |
367 | affs_warning(sb, "get_block", "first block already set (%d)", tmp); | |
368 | AFFS_HEAD(ext_bh)->first_data = cpu_to_be32(blocknr); | |
369 | affs_adjust_checksum(ext_bh, blocknr - tmp); | |
370 | } | |
371 | } | |
372 | ||
373 | affs_brelse(ext_bh); | |
374 | //unlock cache | |
375 | affs_unlock_ext(inode); | |
376 | return 0; | |
377 | ||
378 | err_big: | |
379 | affs_error(inode->i_sb,"get_block","strange block request %d", block); | |
380 | return -EIO; | |
381 | err_ext: | |
382 | // unlock cache | |
383 | affs_unlock_ext(inode); | |
384 | return PTR_ERR(ext_bh); | |
385 | err_alloc: | |
386 | brelse(ext_bh); | |
387 | clear_buffer_mapped(bh_result); | |
388 | bh_result->b_bdev = NULL; | |
389 | // unlock cache | |
390 | affs_unlock_ext(inode); | |
391 | return -ENOSPC; | |
392 | } | |
393 | ||
394 | static int affs_writepage(struct page *page, struct writeback_control *wbc) | |
395 | { | |
396 | return block_write_full_page(page, affs_get_block, wbc); | |
397 | } | |
398 | static int affs_readpage(struct file *file, struct page *page) | |
399 | { | |
400 | return block_read_full_page(page, affs_get_block); | |
401 | } | |
402 | static int affs_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to) | |
403 | { | |
404 | return cont_prepare_write(page, from, to, affs_get_block, | |
405 | &AFFS_I(page->mapping->host)->mmu_private); | |
406 | } | |
407 | static sector_t _affs_bmap(struct address_space *mapping, sector_t block) | |
408 | { | |
409 | return generic_block_bmap(mapping,block,affs_get_block); | |
410 | } | |
f5e54d6e | 411 | const struct address_space_operations affs_aops = { |
1da177e4 LT |
412 | .readpage = affs_readpage, |
413 | .writepage = affs_writepage, | |
414 | .sync_page = block_sync_page, | |
415 | .prepare_write = affs_prepare_write, | |
416 | .commit_write = generic_commit_write, | |
417 | .bmap = _affs_bmap | |
418 | }; | |
419 | ||
420 | static inline struct buffer_head * | |
421 | affs_bread_ino(struct inode *inode, int block, int create) | |
422 | { | |
423 | struct buffer_head *bh, tmp_bh; | |
424 | int err; | |
425 | ||
426 | tmp_bh.b_state = 0; | |
427 | err = affs_get_block(inode, block, &tmp_bh, create); | |
428 | if (!err) { | |
429 | bh = affs_bread(inode->i_sb, tmp_bh.b_blocknr); | |
430 | if (bh) { | |
431 | bh->b_state |= tmp_bh.b_state; | |
432 | return bh; | |
433 | } | |
434 | err = -EIO; | |
435 | } | |
436 | return ERR_PTR(err); | |
437 | } | |
438 | ||
439 | static inline struct buffer_head * | |
440 | affs_getzeroblk_ino(struct inode *inode, int block) | |
441 | { | |
442 | struct buffer_head *bh, tmp_bh; | |
443 | int err; | |
444 | ||
445 | tmp_bh.b_state = 0; | |
446 | err = affs_get_block(inode, block, &tmp_bh, 1); | |
447 | if (!err) { | |
448 | bh = affs_getzeroblk(inode->i_sb, tmp_bh.b_blocknr); | |
449 | if (bh) { | |
450 | bh->b_state |= tmp_bh.b_state; | |
451 | return bh; | |
452 | } | |
453 | err = -EIO; | |
454 | } | |
455 | return ERR_PTR(err); | |
456 | } | |
457 | ||
458 | static inline struct buffer_head * | |
459 | affs_getemptyblk_ino(struct inode *inode, int block) | |
460 | { | |
461 | struct buffer_head *bh, tmp_bh; | |
462 | int err; | |
463 | ||
464 | tmp_bh.b_state = 0; | |
465 | err = affs_get_block(inode, block, &tmp_bh, 1); | |
466 | if (!err) { | |
467 | bh = affs_getemptyblk(inode->i_sb, tmp_bh.b_blocknr); | |
468 | if (bh) { | |
469 | bh->b_state |= tmp_bh.b_state; | |
470 | return bh; | |
471 | } | |
472 | err = -EIO; | |
473 | } | |
474 | return ERR_PTR(err); | |
475 | } | |
476 | ||
1da177e4 LT |
477 | static int |
478 | affs_do_readpage_ofs(struct file *file, struct page *page, unsigned from, unsigned to) | |
479 | { | |
480 | struct inode *inode = page->mapping->host; | |
481 | struct super_block *sb = inode->i_sb; | |
482 | struct buffer_head *bh; | |
483 | char *data; | |
484 | u32 bidx, boff, bsize; | |
485 | u32 tmp; | |
486 | ||
487 | pr_debug("AFFS: read_page(%u, %ld, %d, %d)\n", (u32)inode->i_ino, page->index, from, to); | |
488 | if (from > to || to > PAGE_CACHE_SIZE) | |
489 | BUG(); | |
490 | kmap(page); | |
491 | data = page_address(page); | |
492 | bsize = AFFS_SB(sb)->s_data_blksize; | |
493 | tmp = (page->index << PAGE_CACHE_SHIFT) + from; | |
494 | bidx = tmp / bsize; | |
495 | boff = tmp % bsize; | |
496 | ||
497 | while (from < to) { | |
498 | bh = affs_bread_ino(inode, bidx, 0); | |
499 | if (IS_ERR(bh)) | |
500 | return PTR_ERR(bh); | |
501 | tmp = min(bsize - boff, to - from); | |
502 | if (from + tmp > to || tmp > bsize) | |
503 | BUG(); | |
504 | memcpy(data + from, AFFS_DATA(bh) + boff, tmp); | |
505 | affs_brelse(bh); | |
506 | bidx++; | |
507 | from += tmp; | |
508 | boff = 0; | |
509 | } | |
510 | flush_dcache_page(page); | |
511 | kunmap(page); | |
512 | return 0; | |
513 | } | |
514 | ||
515 | static int | |
516 | affs_extent_file_ofs(struct inode *inode, u32 newsize) | |
517 | { | |
518 | struct super_block *sb = inode->i_sb; | |
519 | struct buffer_head *bh, *prev_bh; | |
520 | u32 bidx, boff; | |
521 | u32 size, bsize; | |
522 | u32 tmp; | |
523 | ||
524 | pr_debug("AFFS: extent_file(%u, %d)\n", (u32)inode->i_ino, newsize); | |
525 | bsize = AFFS_SB(sb)->s_data_blksize; | |
526 | bh = NULL; | |
527 | size = AFFS_I(inode)->mmu_private; | |
528 | bidx = size / bsize; | |
529 | boff = size % bsize; | |
530 | if (boff) { | |
531 | bh = affs_bread_ino(inode, bidx, 0); | |
532 | if (IS_ERR(bh)) | |
533 | return PTR_ERR(bh); | |
534 | tmp = min(bsize - boff, newsize - size); | |
535 | if (boff + tmp > bsize || tmp > bsize) | |
536 | BUG(); | |
537 | memset(AFFS_DATA(bh) + boff, 0, tmp); | |
538 | AFFS_DATA_HEAD(bh)->size = cpu_to_be32(be32_to_cpu(AFFS_DATA_HEAD(bh)->size) + tmp); | |
539 | affs_fix_checksum(sb, bh); | |
540 | mark_buffer_dirty_inode(bh, inode); | |
541 | size += tmp; | |
542 | bidx++; | |
543 | } else if (bidx) { | |
544 | bh = affs_bread_ino(inode, bidx - 1, 0); | |
545 | if (IS_ERR(bh)) | |
546 | return PTR_ERR(bh); | |
547 | } | |
548 | ||
549 | while (size < newsize) { | |
550 | prev_bh = bh; | |
551 | bh = affs_getzeroblk_ino(inode, bidx); | |
552 | if (IS_ERR(bh)) | |
553 | goto out; | |
554 | tmp = min(bsize, newsize - size); | |
555 | if (tmp > bsize) | |
556 | BUG(); | |
557 | AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); | |
558 | AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); | |
559 | AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); | |
560 | AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); | |
561 | affs_fix_checksum(sb, bh); | |
562 | bh->b_state &= ~(1UL << BH_New); | |
563 | mark_buffer_dirty_inode(bh, inode); | |
564 | if (prev_bh) { | |
565 | u32 tmp = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); | |
566 | if (tmp) | |
567 | affs_warning(sb, "extent_file_ofs", "next block already set for %d (%d)", bidx, tmp); | |
568 | AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); | |
569 | affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp); | |
570 | mark_buffer_dirty_inode(prev_bh, inode); | |
571 | affs_brelse(prev_bh); | |
572 | } | |
573 | size += bsize; | |
574 | bidx++; | |
575 | } | |
576 | affs_brelse(bh); | |
577 | inode->i_size = AFFS_I(inode)->mmu_private = newsize; | |
578 | return 0; | |
579 | ||
580 | out: | |
581 | inode->i_size = AFFS_I(inode)->mmu_private = newsize; | |
582 | return PTR_ERR(bh); | |
583 | } | |
584 | ||
585 | static int | |
586 | affs_readpage_ofs(struct file *file, struct page *page) | |
587 | { | |
588 | struct inode *inode = page->mapping->host; | |
589 | u32 to; | |
590 | int err; | |
591 | ||
592 | pr_debug("AFFS: read_page(%u, %ld)\n", (u32)inode->i_ino, page->index); | |
593 | to = PAGE_CACHE_SIZE; | |
594 | if (((page->index + 1) << PAGE_CACHE_SHIFT) > inode->i_size) { | |
595 | to = inode->i_size & ~PAGE_CACHE_MASK; | |
596 | memset(page_address(page) + to, 0, PAGE_CACHE_SIZE - to); | |
597 | } | |
598 | ||
599 | err = affs_do_readpage_ofs(file, page, 0, to); | |
600 | if (!err) | |
601 | SetPageUptodate(page); | |
602 | unlock_page(page); | |
603 | return err; | |
604 | } | |
605 | ||
606 | static int affs_prepare_write_ofs(struct file *file, struct page *page, unsigned from, unsigned to) | |
607 | { | |
608 | struct inode *inode = page->mapping->host; | |
609 | u32 size, offset; | |
610 | u32 tmp; | |
611 | int err = 0; | |
612 | ||
613 | pr_debug("AFFS: prepare_write(%u, %ld, %d, %d)\n", (u32)inode->i_ino, page->index, from, to); | |
614 | offset = page->index << PAGE_CACHE_SHIFT; | |
615 | if (offset + from > AFFS_I(inode)->mmu_private) { | |
616 | err = affs_extent_file_ofs(inode, offset + from); | |
617 | if (err) | |
618 | return err; | |
619 | } | |
620 | size = inode->i_size; | |
621 | ||
622 | if (PageUptodate(page)) | |
623 | return 0; | |
624 | ||
625 | if (from) { | |
626 | err = affs_do_readpage_ofs(file, page, 0, from); | |
627 | if (err) | |
628 | return err; | |
629 | } | |
630 | if (to < PAGE_CACHE_SIZE) { | |
f36dca90 | 631 | zero_user_page(page, to, PAGE_CACHE_SIZE - to, KM_USER0); |
1da177e4 LT |
632 | if (size > offset + to) { |
633 | if (size < offset + PAGE_CACHE_SIZE) | |
634 | tmp = size & ~PAGE_CACHE_MASK; | |
635 | else | |
636 | tmp = PAGE_CACHE_SIZE; | |
637 | err = affs_do_readpage_ofs(file, page, to, tmp); | |
638 | } | |
639 | } | |
640 | return err; | |
641 | } | |
642 | ||
643 | static int affs_commit_write_ofs(struct file *file, struct page *page, unsigned from, unsigned to) | |
644 | { | |
645 | struct inode *inode = page->mapping->host; | |
646 | struct super_block *sb = inode->i_sb; | |
647 | struct buffer_head *bh, *prev_bh; | |
648 | char *data; | |
649 | u32 bidx, boff, bsize; | |
650 | u32 tmp; | |
651 | int written; | |
652 | ||
653 | pr_debug("AFFS: commit_write(%u, %ld, %d, %d)\n", (u32)inode->i_ino, page->index, from, to); | |
654 | bsize = AFFS_SB(sb)->s_data_blksize; | |
655 | data = page_address(page); | |
656 | ||
657 | bh = NULL; | |
658 | written = 0; | |
659 | tmp = (page->index << PAGE_CACHE_SHIFT) + from; | |
660 | bidx = tmp / bsize; | |
661 | boff = tmp % bsize; | |
662 | if (boff) { | |
663 | bh = affs_bread_ino(inode, bidx, 0); | |
664 | if (IS_ERR(bh)) | |
665 | return PTR_ERR(bh); | |
666 | tmp = min(bsize - boff, to - from); | |
667 | if (boff + tmp > bsize || tmp > bsize) | |
668 | BUG(); | |
669 | memcpy(AFFS_DATA(bh) + boff, data + from, tmp); | |
670 | AFFS_DATA_HEAD(bh)->size = cpu_to_be32(be32_to_cpu(AFFS_DATA_HEAD(bh)->size) + tmp); | |
671 | affs_fix_checksum(sb, bh); | |
672 | mark_buffer_dirty_inode(bh, inode); | |
673 | written += tmp; | |
674 | from += tmp; | |
675 | bidx++; | |
676 | } else if (bidx) { | |
677 | bh = affs_bread_ino(inode, bidx - 1, 0); | |
678 | if (IS_ERR(bh)) | |
679 | return PTR_ERR(bh); | |
680 | } | |
681 | while (from + bsize <= to) { | |
682 | prev_bh = bh; | |
683 | bh = affs_getemptyblk_ino(inode, bidx); | |
684 | if (IS_ERR(bh)) | |
685 | goto out; | |
686 | memcpy(AFFS_DATA(bh), data + from, bsize); | |
687 | if (buffer_new(bh)) { | |
688 | AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); | |
689 | AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); | |
690 | AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); | |
691 | AFFS_DATA_HEAD(bh)->size = cpu_to_be32(bsize); | |
692 | AFFS_DATA_HEAD(bh)->next = 0; | |
693 | bh->b_state &= ~(1UL << BH_New); | |
694 | if (prev_bh) { | |
695 | u32 tmp = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); | |
696 | if (tmp) | |
697 | affs_warning(sb, "commit_write_ofs", "next block already set for %d (%d)", bidx, tmp); | |
698 | AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); | |
699 | affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp); | |
700 | mark_buffer_dirty_inode(prev_bh, inode); | |
701 | } | |
702 | } | |
703 | affs_brelse(prev_bh); | |
704 | affs_fix_checksum(sb, bh); | |
705 | mark_buffer_dirty_inode(bh, inode); | |
706 | written += bsize; | |
707 | from += bsize; | |
708 | bidx++; | |
709 | } | |
710 | if (from < to) { | |
711 | prev_bh = bh; | |
712 | bh = affs_bread_ino(inode, bidx, 1); | |
713 | if (IS_ERR(bh)) | |
714 | goto out; | |
715 | tmp = min(bsize, to - from); | |
716 | if (tmp > bsize) | |
717 | BUG(); | |
718 | memcpy(AFFS_DATA(bh), data + from, tmp); | |
719 | if (buffer_new(bh)) { | |
720 | AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); | |
721 | AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); | |
722 | AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); | |
723 | AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); | |
724 | AFFS_DATA_HEAD(bh)->next = 0; | |
725 | bh->b_state &= ~(1UL << BH_New); | |
726 | if (prev_bh) { | |
727 | u32 tmp = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); | |
728 | if (tmp) | |
729 | affs_warning(sb, "commit_write_ofs", "next block already set for %d (%d)", bidx, tmp); | |
730 | AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); | |
731 | affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp); | |
732 | mark_buffer_dirty_inode(prev_bh, inode); | |
733 | } | |
734 | } else if (be32_to_cpu(AFFS_DATA_HEAD(bh)->size) < tmp) | |
735 | AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); | |
736 | affs_brelse(prev_bh); | |
737 | affs_fix_checksum(sb, bh); | |
738 | mark_buffer_dirty_inode(bh, inode); | |
739 | written += tmp; | |
740 | from += tmp; | |
741 | bidx++; | |
742 | } | |
743 | SetPageUptodate(page); | |
744 | ||
745 | done: | |
746 | affs_brelse(bh); | |
747 | tmp = (page->index << PAGE_CACHE_SHIFT) + from; | |
748 | if (tmp > inode->i_size) | |
749 | inode->i_size = AFFS_I(inode)->mmu_private = tmp; | |
750 | ||
751 | return written; | |
752 | ||
753 | out: | |
754 | bh = prev_bh; | |
755 | if (!written) | |
756 | written = PTR_ERR(bh); | |
757 | goto done; | |
758 | } | |
759 | ||
f5e54d6e | 760 | const struct address_space_operations affs_aops_ofs = { |
1da177e4 LT |
761 | .readpage = affs_readpage_ofs, |
762 | //.writepage = affs_writepage_ofs, | |
763 | //.sync_page = affs_sync_page_ofs, | |
764 | .prepare_write = affs_prepare_write_ofs, | |
765 | .commit_write = affs_commit_write_ofs | |
766 | }; | |
767 | ||
768 | /* Free any preallocated blocks. */ | |
769 | ||
770 | void | |
771 | affs_free_prealloc(struct inode *inode) | |
772 | { | |
773 | struct super_block *sb = inode->i_sb; | |
774 | ||
775 | pr_debug("AFFS: free_prealloc(ino=%lu)\n", inode->i_ino); | |
776 | ||
777 | while (AFFS_I(inode)->i_pa_cnt) { | |
778 | AFFS_I(inode)->i_pa_cnt--; | |
779 | affs_free_block(sb, ++AFFS_I(inode)->i_lastalloc); | |
780 | } | |
781 | } | |
782 | ||
783 | /* Truncate (or enlarge) a file to the requested size. */ | |
784 | ||
785 | void | |
786 | affs_truncate(struct inode *inode) | |
787 | { | |
788 | struct super_block *sb = inode->i_sb; | |
789 | u32 ext, ext_key; | |
790 | u32 last_blk, blkcnt, blk; | |
791 | u32 size; | |
792 | struct buffer_head *ext_bh; | |
793 | int i; | |
794 | ||
795 | pr_debug("AFFS: truncate(inode=%d, oldsize=%u, newsize=%u)\n", | |
796 | (u32)inode->i_ino, (u32)AFFS_I(inode)->mmu_private, (u32)inode->i_size); | |
797 | ||
798 | last_blk = 0; | |
799 | ext = 0; | |
800 | if (inode->i_size) { | |
801 | last_blk = ((u32)inode->i_size - 1) / AFFS_SB(sb)->s_data_blksize; | |
802 | ext = last_blk / AFFS_SB(sb)->s_hashsize; | |
803 | } | |
804 | ||
805 | if (inode->i_size > AFFS_I(inode)->mmu_private) { | |
806 | struct address_space *mapping = inode->i_mapping; | |
807 | struct page *page; | |
808 | u32 size = inode->i_size - 1; | |
809 | int res; | |
810 | ||
811 | page = grab_cache_page(mapping, size >> PAGE_CACHE_SHIFT); | |
812 | if (!page) | |
813 | return; | |
814 | size = (size & (PAGE_CACHE_SIZE - 1)) + 1; | |
815 | res = mapping->a_ops->prepare_write(NULL, page, size, size); | |
816 | if (!res) | |
817 | res = mapping->a_ops->commit_write(NULL, page, size, size); | |
818 | unlock_page(page); | |
819 | page_cache_release(page); | |
820 | mark_inode_dirty(inode); | |
821 | return; | |
822 | } else if (inode->i_size == AFFS_I(inode)->mmu_private) | |
823 | return; | |
824 | ||
825 | // lock cache | |
826 | ext_bh = affs_get_extblock(inode, ext); | |
827 | if (IS_ERR(ext_bh)) { | |
828 | affs_warning(sb, "truncate", "unexpected read error for ext block %u (%d)", | |
829 | ext, PTR_ERR(ext_bh)); | |
830 | return; | |
831 | } | |
832 | if (AFFS_I(inode)->i_lc) { | |
833 | /* clear linear cache */ | |
834 | i = (ext + 1) >> AFFS_I(inode)->i_lc_shift; | |
835 | if (AFFS_I(inode)->i_lc_size > i) { | |
836 | AFFS_I(inode)->i_lc_size = i; | |
837 | for (; i < AFFS_LC_SIZE; i++) | |
838 | AFFS_I(inode)->i_lc[i] = 0; | |
839 | } | |
840 | /* clear associative cache */ | |
841 | for (i = 0; i < AFFS_AC_SIZE; i++) | |
842 | if (AFFS_I(inode)->i_ac[i].ext >= ext) | |
843 | AFFS_I(inode)->i_ac[i].ext = 0; | |
844 | } | |
845 | ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension); | |
846 | ||
847 | blkcnt = AFFS_I(inode)->i_blkcnt; | |
848 | i = 0; | |
849 | blk = last_blk; | |
850 | if (inode->i_size) { | |
851 | i = last_blk % AFFS_SB(sb)->s_hashsize + 1; | |
852 | blk++; | |
853 | } else | |
854 | AFFS_HEAD(ext_bh)->first_data = 0; | |
855 | size = AFFS_SB(sb)->s_hashsize; | |
856 | if (size > blkcnt - blk + i) | |
857 | size = blkcnt - blk + i; | |
858 | for (; i < size; i++, blk++) { | |
859 | affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i))); | |
860 | AFFS_BLOCK(sb, ext_bh, i) = 0; | |
861 | } | |
862 | AFFS_TAIL(sb, ext_bh)->extension = 0; | |
863 | affs_fix_checksum(sb, ext_bh); | |
864 | mark_buffer_dirty_inode(ext_bh, inode); | |
865 | affs_brelse(ext_bh); | |
866 | ||
867 | if (inode->i_size) { | |
868 | AFFS_I(inode)->i_blkcnt = last_blk + 1; | |
869 | AFFS_I(inode)->i_extcnt = ext + 1; | |
870 | if (AFFS_SB(sb)->s_flags & SF_OFS) { | |
871 | struct buffer_head *bh = affs_bread_ino(inode, last_blk, 0); | |
872 | u32 tmp; | |
873 | if (IS_ERR(ext_bh)) { | |
874 | affs_warning(sb, "truncate", "unexpected read error for last block %u (%d)", | |
875 | ext, PTR_ERR(ext_bh)); | |
876 | return; | |
877 | } | |
878 | tmp = be32_to_cpu(AFFS_DATA_HEAD(bh)->next); | |
879 | AFFS_DATA_HEAD(bh)->next = 0; | |
880 | affs_adjust_checksum(bh, -tmp); | |
881 | affs_brelse(bh); | |
882 | } | |
883 | } else { | |
884 | AFFS_I(inode)->i_blkcnt = 0; | |
885 | AFFS_I(inode)->i_extcnt = 1; | |
886 | } | |
887 | AFFS_I(inode)->mmu_private = inode->i_size; | |
888 | // unlock cache | |
889 | ||
890 | while (ext_key) { | |
891 | ext_bh = affs_bread(sb, ext_key); | |
892 | size = AFFS_SB(sb)->s_hashsize; | |
893 | if (size > blkcnt - blk) | |
894 | size = blkcnt - blk; | |
895 | for (i = 0; i < size; i++, blk++) | |
896 | affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i))); | |
897 | affs_free_block(sb, ext_key); | |
898 | ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension); | |
899 | affs_brelse(ext_bh); | |
900 | } | |
901 | affs_free_prealloc(inode); | |
902 | } |