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fs/affs/file.c: replace if/BUG by BUG_ON
[mirror_ubuntu-zesty-kernel.git] / fs / affs / file.c
CommitLineData
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
9abb4083 15#include <linux/aio.h>
1da177e4
LT		 16#include "affs.h"
17
1da177e4 18static struct buffer_head *affs_get_extblock_slow(struct inode *inode, u32 ext);
1da177e4
LT		 19
20static int
21affs_file_open(struct inode *inode, struct file *filp)
22{
9606d9aa 23 pr_debug("open(%lu,%d)\n",
dca3c336
RZ		 24 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
25 atomic_inc(&AFFS_I(inode)->i_opencnt);
1da177e4
LT		 26 return 0;
27}
28
29static int
30affs_file_release(struct inode *inode, struct file *filp)
31{
9606d9aa 32 pr_debug("release(%lu, %d)\n",
dca3c336
RZ		 33 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
34
35 if (atomic_dec_and_test(&AFFS_I(inode)->i_opencnt)) {
36 mutex_lock(&inode->i_mutex);
37 if (inode->i_size != AFFS_I(inode)->mmu_private)
38 affs_truncate(inode);
1da177e4 39 affs_free_prealloc(inode);
dca3c336
RZ		 40 mutex_unlock(&inode->i_mutex);
41 }
1da177e4
LT		 42
43 return 0;
44}
45
46static int
47affs_grow_extcache(struct inode *inode, u32 lc_idx)
48{
49 struct super_block *sb = inode->i_sb;
50 struct buffer_head *bh;
51 u32 lc_max;
52 int i, j, key;
53
54 if (!AFFS_I(inode)->i_lc) {
55 char *ptr = (char *)get_zeroed_page(GFP_NOFS);
56 if (!ptr)
57 return -ENOMEM;
58 AFFS_I(inode)->i_lc = (u32 *)ptr;
59 AFFS_I(inode)->i_ac = (struct affs_ext_key *)(ptr + AFFS_CACHE_SIZE / 2);
60 }
61
62 lc_max = AFFS_LC_SIZE << AFFS_I(inode)->i_lc_shift;
63
64 if (AFFS_I(inode)->i_extcnt > lc_max) {
65 u32 lc_shift, lc_mask, tmp, off;
66
67 /* need to recalculate linear cache, start from old size */
68 lc_shift = AFFS_I(inode)->i_lc_shift;
69 tmp = (AFFS_I(inode)->i_extcnt / AFFS_LC_SIZE) >> lc_shift;
70 for (; tmp; tmp >>= 1)
71 lc_shift++;
72 lc_mask = (1 << lc_shift) - 1;
73
74 /* fix idx and old size to new shift */
75 lc_idx >>= (lc_shift - AFFS_I(inode)->i_lc_shift);
76 AFFS_I(inode)->i_lc_size >>= (lc_shift - AFFS_I(inode)->i_lc_shift);
77
78 /* first shrink old cache to make more space */
79 off = 1 << (lc_shift - AFFS_I(inode)->i_lc_shift);
80 for (i = 1, j = off; j < AFFS_LC_SIZE; i++, j += off)
81 AFFS_I(inode)->i_ac[i] = AFFS_I(inode)->i_ac[j];
82
83 AFFS_I(inode)->i_lc_shift = lc_shift;
84 AFFS_I(inode)->i_lc_mask = lc_mask;
85 }
86
87 /* fill cache to the needed index */
88 i = AFFS_I(inode)->i_lc_size;
89 AFFS_I(inode)->i_lc_size = lc_idx + 1;
90 for (; i <= lc_idx; i++) {
91 if (!i) {
92 AFFS_I(inode)->i_lc[0] = inode->i_ino;
93 continue;
94 }
95 key = AFFS_I(inode)->i_lc[i - 1];
96 j = AFFS_I(inode)->i_lc_mask + 1;
97 // unlock cache
98 for (; j > 0; j--) {
99 bh = affs_bread(sb, key);
100 if (!bh)
101 goto err;
102 key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
103 affs_brelse(bh);
104 }
105 // lock cache
106 AFFS_I(inode)->i_lc[i] = key;
107 }
108
109 return 0;
110
111err:
112 // lock cache
113 return -EIO;
114}
115
116static struct buffer_head *
117affs_alloc_extblock(struct inode *inode, struct buffer_head *bh, u32 ext)
118{
119 struct super_block *sb = inode->i_sb;
120 struct buffer_head *new_bh;
121 u32 blocknr, tmp;
122
123 blocknr = affs_alloc_block(inode, bh->b_blocknr);
124 if (!blocknr)
125 return ERR_PTR(-ENOSPC);
126
127 new_bh = affs_getzeroblk(sb, blocknr);
128 if (!new_bh) {
129 affs_free_block(sb, blocknr);
130 return ERR_PTR(-EIO);
131 }
132
133 AFFS_HEAD(new_bh)->ptype = cpu_to_be32(T_LIST);
134 AFFS_HEAD(new_bh)->key = cpu_to_be32(blocknr);
135 AFFS_TAIL(sb, new_bh)->stype = cpu_to_be32(ST_FILE);
136 AFFS_TAIL(sb, new_bh)->parent = cpu_to_be32(inode->i_ino);
137 affs_fix_checksum(sb, new_bh);
138
139 mark_buffer_dirty_inode(new_bh, inode);
140
141 tmp = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
142 if (tmp)
143 affs_warning(sb, "alloc_ext", "previous extension set (%x)", tmp);
144 AFFS_TAIL(sb, bh)->extension = cpu_to_be32(blocknr);
145 affs_adjust_checksum(bh, blocknr - tmp);
146 mark_buffer_dirty_inode(bh, inode);
147
148 AFFS_I(inode)->i_extcnt++;
149 mark_inode_dirty(inode);
150
151 return new_bh;
152}
153
154static inline struct buffer_head *
155affs_get_extblock(struct inode *inode, u32 ext)
156{
157 /* inline the simplest case: same extended block as last time */
158 struct buffer_head *bh = AFFS_I(inode)->i_ext_bh;
159 if (ext == AFFS_I(inode)->i_ext_last)
dca3c336 160 get_bh(bh);
1da177e4
LT		 161 else
162 /* we have to do more (not inlined) */
163 bh = affs_get_extblock_slow(inode, ext);
164
165 return bh;
166}
167
168static struct buffer_head *
169affs_get_extblock_slow(struct inode *inode, u32 ext)
170{
171 struct super_block *sb = inode->i_sb;
172 struct buffer_head *bh;
173 u32 ext_key;
174 u32 lc_idx, lc_off, ac_idx;
175 u32 tmp, idx;
176
177 if (ext == AFFS_I(inode)->i_ext_last + 1) {
178 /* read the next extended block from the current one */
179 bh = AFFS_I(inode)->i_ext_bh;
180 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
181 if (ext < AFFS_I(inode)->i_extcnt)
182 goto read_ext;
afe305dc 183 BUG_ON(ext > AFFS_I(inode)->i_extcnt);
1da177e4
LT		 184 bh = affs_alloc_extblock(inode, bh, ext);
185 if (IS_ERR(bh))
186 return bh;
187 goto store_ext;
188 }
189
190 if (ext == 0) {
191 /* we seek back to the file header block */
192 ext_key = inode->i_ino;
193 goto read_ext;
194 }
195
196 if (ext >= AFFS_I(inode)->i_extcnt) {
197 struct buffer_head *prev_bh;
198
199 /* allocate a new extended block */
afe305dc 200 BUG_ON(ext > AFFS_I(inode)->i_extcnt);
1da177e4
LT		 201
202 /* get previous extended block */
203 prev_bh = affs_get_extblock(inode, ext - 1);
204 if (IS_ERR(prev_bh))
205 return prev_bh;
206 bh = affs_alloc_extblock(inode, prev_bh, ext);
207 affs_brelse(prev_bh);
208 if (IS_ERR(bh))
209 return bh;
210 goto store_ext;
211 }
212
213again:
214 /* check if there is an extended cache and whether it's large enough */
215 lc_idx = ext >> AFFS_I(inode)->i_lc_shift;
216 lc_off = ext & AFFS_I(inode)->i_lc_mask;
217
218 if (lc_idx >= AFFS_I(inode)->i_lc_size) {
219 int err;
220
221 err = affs_grow_extcache(inode, lc_idx);
222 if (err)
223 return ERR_PTR(err);
224 goto again;
225 }
226
227 /* every n'th key we find in the linear cache */
228 if (!lc_off) {
229 ext_key = AFFS_I(inode)->i_lc[lc_idx];
230 goto read_ext;
231 }
232
233 /* maybe it's still in the associative cache */
234 ac_idx = (ext - lc_idx - 1) & AFFS_AC_MASK;
235 if (AFFS_I(inode)->i_ac[ac_idx].ext == ext) {
236 ext_key = AFFS_I(inode)->i_ac[ac_idx].key;
237 goto read_ext;
238 }
239
240 /* try to find one of the previous extended blocks */
241 tmp = ext;
242 idx = ac_idx;
243 while (--tmp, --lc_off > 0) {
244 idx = (idx - 1) & AFFS_AC_MASK;
245 if (AFFS_I(inode)->i_ac[idx].ext == tmp) {
246 ext_key = AFFS_I(inode)->i_ac[idx].key;
247 goto find_ext;
248 }
249 }
250
251 /* fall back to the linear cache */
252 ext_key = AFFS_I(inode)->i_lc[lc_idx];
253find_ext:
254 /* read all extended blocks until we find the one we need */
255 //unlock cache
256 do {
257 bh = affs_bread(sb, ext_key);
258 if (!bh)
259 goto err_bread;
260 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
261 affs_brelse(bh);
262 tmp++;
263 } while (tmp < ext);
264 //lock cache
265
266 /* store it in the associative cache */
267 // recalculate ac_idx?
268 AFFS_I(inode)->i_ac[ac_idx].ext = ext;
269 AFFS_I(inode)->i_ac[ac_idx].key = ext_key;
270
271read_ext:
272 /* finally read the right extended block */
273 //unlock cache
274 bh = affs_bread(sb, ext_key);
275 if (!bh)
276 goto err_bread;
277 //lock cache
278
279store_ext:
280 /* release old cached extended block and store the new one */
281 affs_brelse(AFFS_I(inode)->i_ext_bh);
282 AFFS_I(inode)->i_ext_last = ext;
283 AFFS_I(inode)->i_ext_bh = bh;
dca3c336 284 get_bh(bh);
1da177e4
LT		 285
286 return bh;
287
288err_bread:
289 affs_brelse(bh);
290 return ERR_PTR(-EIO);
291}
292
293static int
294affs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh_result, int create)
295{
296 struct super_block *sb = inode->i_sb;
297 struct buffer_head *ext_bh;
298 u32 ext;
299
08fe100d
GU		 300 pr_debug("%s(%lu, %llu)\n", __func__, inode->i_ino,
301 (unsigned long long)block);
1da177e4 302
8d4b6900 303 BUG_ON(block > (sector_t)0x7fffffffUL);
1da177e4
LT		 304
305 if (block >= AFFS_I(inode)->i_blkcnt) {
306 if (block > AFFS_I(inode)->i_blkcnt || !create)
307 goto err_big;
308 } else
309 create = 0;
310
311 //lock cache
312 affs_lock_ext(inode);
313
314 ext = (u32)block / AFFS_SB(sb)->s_hashsize;
315 block -= ext * AFFS_SB(sb)->s_hashsize;
316 ext_bh = affs_get_extblock(inode, ext);
317 if (IS_ERR(ext_bh))
318 goto err_ext;
319 map_bh(bh_result, sb, (sector_t)be32_to_cpu(AFFS_BLOCK(sb, ext_bh, block)));
320
321 if (create) {
322 u32 blocknr = affs_alloc_block(inode, ext_bh->b_blocknr);
323 if (!blocknr)
324 goto err_alloc;
325 set_buffer_new(bh_result);
326 AFFS_I(inode)->mmu_private += AFFS_SB(sb)->s_data_blksize;
327 AFFS_I(inode)->i_blkcnt++;
328
329 /* store new block */
330 if (bh_result->b_blocknr)
08fe100d
GU		 331 affs_warning(sb, "get_block",
332 "block already set (%llx)",
333 (unsigned long long)bh_result->b_blocknr);
1da177e4
LT		 334 AFFS_BLOCK(sb, ext_bh, block) = cpu_to_be32(blocknr);
335 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(block + 1);
336 affs_adjust_checksum(ext_bh, blocknr - bh_result->b_blocknr + 1);
337 bh_result->b_blocknr = blocknr;
338
339 if (!block) {
340 /* insert first block into header block */
341 u32 tmp = be32_to_cpu(AFFS_HEAD(ext_bh)->first_data);
342 if (tmp)
343 affs_warning(sb, "get_block", "first block already set (%d)", tmp);
344 AFFS_HEAD(ext_bh)->first_data = cpu_to_be32(blocknr);
345 affs_adjust_checksum(ext_bh, blocknr - tmp);
346 }
347 }
348
349 affs_brelse(ext_bh);
350 //unlock cache
351 affs_unlock_ext(inode);
352 return 0;
353
354err_big:
08fe100d
GU		 355 affs_error(inode->i_sb, "get_block", "strange block request %llu",
356 (unsigned long long)block);
1da177e4
LT		 357 return -EIO;
358err_ext:
359 // unlock cache
360 affs_unlock_ext(inode);
361 return PTR_ERR(ext_bh);
362err_alloc:
363 brelse(ext_bh);
364 clear_buffer_mapped(bh_result);
365 bh_result->b_bdev = NULL;
366 // unlock cache
367 affs_unlock_ext(inode);
368 return -ENOSPC;
369}
370
371static int affs_writepage(struct page *page, struct writeback_control *wbc)
372{
373 return block_write_full_page(page, affs_get_block, wbc);
374}
f2b6a16e 375
1da177e4
LT		 376static int affs_readpage(struct file *file, struct page *page)
377{
378 return block_read_full_page(page, affs_get_block);
379}
f2b6a16e 380
1dc1834f
MS		 381static void affs_write_failed(struct address_space *mapping, loff_t to)
382{
383 struct inode *inode = mapping->host;
384
385 if (to > inode->i_size) {
7caef267 386 truncate_pagecache(inode, inode->i_size);
1dc1834f
MS		 387 affs_truncate(inode);
388 }
389}
390
9abb4083
FF		 391static ssize_t
392affs_direct_IO(int rw, struct kiocb *iocb, struct iov_iter *iter,
393 loff_t offset)
394{
395 struct file *file = iocb->ki_filp;
396 struct address_space *mapping = file->f_mapping;
397 struct inode *inode = mapping->host;
398 size_t count = iov_iter_count(iter);
399 ssize_t ret;
400
401 ret = blockdev_direct_IO(rw, iocb, inode, iter, offset, affs_get_block);
402 if (ret < 0 && (rw & WRITE))
403 affs_write_failed(mapping, offset + count);
404 return ret;
405}
406
f2b6a16e
NP		 407static int affs_write_begin(struct file *file, struct address_space *mapping,
408 loff_t pos, unsigned len, unsigned flags,
409 struct page **pagep, void **fsdata)
1da177e4 410{
282dc178
CH		 411 int ret;
412
f2b6a16e 413 *pagep = NULL;
282dc178 414 ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
f2b6a16e
NP		 415 affs_get_block,
416 &AFFS_I(mapping->host)->mmu_private);
1dc1834f
MS		 417 if (unlikely(ret))
418 affs_write_failed(mapping, pos + len);
282dc178
CH		 419
420 return ret;
1da177e4 421}
f2b6a16e 422
1da177e4
LT		 423static sector_t _affs_bmap(struct address_space *mapping, sector_t block)
424{
425 return generic_block_bmap(mapping,block,affs_get_block);
426}
f2b6a16e 427
f5e54d6e 428const struct address_space_operations affs_aops = {
1da177e4
LT		 429 .readpage = affs_readpage,
430 .writepage = affs_writepage,
f2b6a16e
NP		 431 .write_begin = affs_write_begin,
432 .write_end = generic_write_end,
9abb4083 433 .direct_IO = affs_direct_IO,
1da177e4
LT		 434 .bmap = _affs_bmap
435};
436
437static inline struct buffer_head *
438affs_bread_ino(struct inode *inode, int block, int create)
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, create);
445 if (!err) {
446 bh = affs_bread(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
456static inline struct buffer_head *
457affs_getzeroblk_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_getzeroblk(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
475static inline struct buffer_head *
476affs_getemptyblk_ino(struct inode *inode, int block)
477{
478 struct buffer_head *bh, tmp_bh;
479 int err;
480
481 tmp_bh.b_state = 0;
482 err = affs_get_block(inode, block, &tmp_bh, 1);
483 if (!err) {
484 bh = affs_getemptyblk(inode->i_sb, tmp_bh.b_blocknr);
485 if (bh) {
486 bh->b_state |= tmp_bh.b_state;
487 return bh;
488 }
489 err = -EIO;
490 }
491 return ERR_PTR(err);
492}
493
1da177e4 494static int
0c89d670 495affs_do_readpage_ofs(struct page *page, unsigned to)
1da177e4
LT		 496{
497 struct inode *inode = page->mapping->host;
498 struct super_block *sb = inode->i_sb;
499 struct buffer_head *bh;
500 char *data;
0c89d670 501 unsigned pos = 0;
1da177e4
LT		 502 u32 bidx, boff, bsize;
503 u32 tmp;
504
08fe100d 505 pr_debug("%s(%lu, %ld, 0, %d)\n", __func__, inode->i_ino,
0c89d670
FF		 506 page->index, to);
507 BUG_ON(to > PAGE_CACHE_SIZE);
1da177e4
LT		 508 kmap(page);
509 data = page_address(page);
510 bsize = AFFS_SB(sb)->s_data_blksize;
0c89d670 511 tmp = page->index << PAGE_CACHE_SHIFT;
1da177e4
LT		 512 bidx = tmp / bsize;
513 boff = tmp % bsize;
514
0c89d670 515 while (pos < to) {
1da177e4
LT		 516 bh = affs_bread_ino(inode, bidx, 0);
517 if (IS_ERR(bh))
518 return PTR_ERR(bh);
0c89d670
FF		 519 tmp = min(bsize - boff, to - pos);
520 BUG_ON(pos + tmp > to || tmp > bsize);
521 memcpy(data + pos, AFFS_DATA(bh) + boff, tmp);
1da177e4
LT		 522 affs_brelse(bh);
523 bidx++;
0c89d670 524 pos += tmp;
1da177e4
LT		 525 boff = 0;
526 }
527 flush_dcache_page(page);
528 kunmap(page);
529 return 0;
530}
531
532static int
533affs_extent_file_ofs(struct inode *inode, u32 newsize)
534{
535 struct super_block *sb = inode->i_sb;
536 struct buffer_head *bh, *prev_bh;
537 u32 bidx, boff;
538 u32 size, bsize;
539 u32 tmp;
540
08fe100d 541 pr_debug("%s(%lu, %d)\n", __func__, inode->i_ino, newsize);
1da177e4
LT		 542 bsize = AFFS_SB(sb)->s_data_blksize;
543 bh = NULL;
544 size = AFFS_I(inode)->mmu_private;
545 bidx = size / bsize;
546 boff = size % bsize;
547 if (boff) {
548 bh = affs_bread_ino(inode, bidx, 0);
549 if (IS_ERR(bh))
550 return PTR_ERR(bh);
551 tmp = min(bsize - boff, newsize - size);
8d4b6900 552 BUG_ON(boff + tmp > bsize || tmp > bsize);
1da177e4 553 memset(AFFS_DATA(bh) + boff, 0, tmp);
6369a4ab 554 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp);
1da177e4
LT		 555 affs_fix_checksum(sb, bh);
556 mark_buffer_dirty_inode(bh, inode);
557 size += tmp;
558 bidx++;
559 } else if (bidx) {
560 bh = affs_bread_ino(inode, bidx - 1, 0);
561 if (IS_ERR(bh))
562 return PTR_ERR(bh);
563 }
564
565 while (size < newsize) {
566 prev_bh = bh;
567 bh = affs_getzeroblk_ino(inode, bidx);
568 if (IS_ERR(bh))
569 goto out;
570 tmp = min(bsize, newsize - size);
8d4b6900 571 BUG_ON(tmp > bsize);
1da177e4
LT		 572 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
573 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
574 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
575 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
576 affs_fix_checksum(sb, bh);
577 bh->b_state &= ~(1UL << BH_New);
578 mark_buffer_dirty_inode(bh, inode);
579 if (prev_bh) {
73516ace
FF		 580 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
581
582 if (tmp_next)
583 affs_warning(sb, "extent_file_ofs",
584 "next block already set for %d (%d)",
585 bidx, tmp_next);
1da177e4 586 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
73516ace 587 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
1da177e4
LT		 588 mark_buffer_dirty_inode(prev_bh, inode);
589 affs_brelse(prev_bh);
590 }
591 size += bsize;
592 bidx++;
593 }
594 affs_brelse(bh);
595 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
596 return 0;
597
598out:
599 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
600 return PTR_ERR(bh);
601}
602
603static int
604affs_readpage_ofs(struct file *file, struct page *page)
605{
606 struct inode *inode = page->mapping->host;
607 u32 to;
608 int err;
609
08fe100d 610 pr_debug("%s(%lu, %ld)\n", __func__, inode->i_ino, page->index);
1da177e4
LT		 611 to = PAGE_CACHE_SIZE;
612 if (((page->index + 1) << PAGE_CACHE_SHIFT) > inode->i_size) {
613 to = inode->i_size & ~PAGE_CACHE_MASK;
614 memset(page_address(page) + to, 0, PAGE_CACHE_SIZE - to);
615 }
616
0c89d670 617 err = affs_do_readpage_ofs(page, to);
1da177e4
LT		 618 if (!err)
619 SetPageUptodate(page);
620 unlock_page(page);
621 return err;
622}
623
f2b6a16e
NP		 624static int affs_write_begin_ofs(struct file *file, struct address_space *mapping,
625 loff_t pos, unsigned len, unsigned flags,
626 struct page **pagep, void **fsdata)
1da177e4 627{
f2b6a16e
NP		 628 struct inode *inode = mapping->host;
629 struct page *page;
630 pgoff_t index;
1da177e4
LT		 631 int err = 0;
632
08fe100d
GU		 633 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos,
634 pos + len);
f2b6a16e
NP		 635 if (pos > AFFS_I(inode)->mmu_private) {
636 /* XXX: this probably leaves a too-big i_size in case of
637 * failure. Should really be updating i_size at write_end time
638 */
639 err = affs_extent_file_ofs(inode, pos);
1da177e4
LT		 640 if (err)
641 return err;
642 }
f2b6a16e
NP		 643
644 index = pos >> PAGE_CACHE_SHIFT;
54566b2c 645 page = grab_cache_page_write_begin(mapping, index, flags);
f2b6a16e
NP		 646 if (!page)
647 return -ENOMEM;
648 *pagep = page;
1da177e4
LT		 649
650 if (PageUptodate(page))
651 return 0;
652
f2b6a16e 653 /* XXX: inefficient but safe in the face of short writes */
0c89d670 654 err = affs_do_readpage_ofs(page, PAGE_CACHE_SIZE);
f2b6a16e
NP		 655 if (err) {
656 unlock_page(page);
657 page_cache_release(page);
1da177e4
LT		 658 }
659 return err;
660}
661
f2b6a16e
NP		 662static int affs_write_end_ofs(struct file *file, struct address_space *mapping,
663 loff_t pos, unsigned len, unsigned copied,
664 struct page *page, void *fsdata)
1da177e4 665{
f2b6a16e 666 struct inode *inode = mapping->host;
1da177e4
LT		 667 struct super_block *sb = inode->i_sb;
668 struct buffer_head *bh, *prev_bh;
669 char *data;
670 u32 bidx, boff, bsize;
f2b6a16e 671 unsigned from, to;
1da177e4
LT		 672 u32 tmp;
673 int written;
674
f2b6a16e
NP		 675 from = pos & (PAGE_CACHE_SIZE - 1);
676 to = pos + len;
677 /*
678 * XXX: not sure if this can handle short copies (len < copied), but
679 * we don't have to, because the page should always be uptodate here,
680 * due to write_begin.
681 */
682
08fe100d
GU		 683 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos,
684 pos + len);
1da177e4
LT		 685 bsize = AFFS_SB(sb)->s_data_blksize;
686 data = page_address(page);
687
688 bh = NULL;
689 written = 0;
690 tmp = (page->index << PAGE_CACHE_SHIFT) + from;
691 bidx = tmp / bsize;
692 boff = tmp % bsize;
693 if (boff) {
694 bh = affs_bread_ino(inode, bidx, 0);
695 if (IS_ERR(bh))
696 return PTR_ERR(bh);
697 tmp = min(bsize - boff, to - from);
8d4b6900 698 BUG_ON(boff + tmp > bsize || tmp > bsize);
1da177e4 699 memcpy(AFFS_DATA(bh) + boff, data + from, tmp);
6369a4ab 700 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp);
1da177e4
LT		 701 affs_fix_checksum(sb, bh);
702 mark_buffer_dirty_inode(bh, inode);
703 written += tmp;
704 from += tmp;
705 bidx++;
706 } else if (bidx) {
707 bh = affs_bread_ino(inode, bidx - 1, 0);
708 if (IS_ERR(bh))
709 return PTR_ERR(bh);
710 }
711 while (from + bsize <= to) {
712 prev_bh = bh;
713 bh = affs_getemptyblk_ino(inode, bidx);
714 if (IS_ERR(bh))
715 goto out;
716 memcpy(AFFS_DATA(bh), data + from, bsize);
717 if (buffer_new(bh)) {
718 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
719 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
720 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
721 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(bsize);
722 AFFS_DATA_HEAD(bh)->next = 0;
723 bh->b_state &= ~(1UL << BH_New);
724 if (prev_bh) {
73516ace
FF		 725 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
726
727 if (tmp_next)
728 affs_warning(sb, "commit_write_ofs",
729 "next block already set for %d (%d)",
730 bidx, tmp_next);
1da177e4 731 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
73516ace 732 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
1da177e4
LT		 733 mark_buffer_dirty_inode(prev_bh, inode);
734 }
735 }
736 affs_brelse(prev_bh);
737 affs_fix_checksum(sb, bh);
738 mark_buffer_dirty_inode(bh, inode);
739 written += bsize;
740 from += bsize;
741 bidx++;
742 }
743 if (from < to) {
744 prev_bh = bh;
745 bh = affs_bread_ino(inode, bidx, 1);
746 if (IS_ERR(bh))
747 goto out;
748 tmp = min(bsize, to - from);
8d4b6900 749 BUG_ON(tmp > bsize);
1da177e4
LT		 750 memcpy(AFFS_DATA(bh), data + from, tmp);
751 if (buffer_new(bh)) {
752 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
753 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
754 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
755 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
756 AFFS_DATA_HEAD(bh)->next = 0;
757 bh->b_state &= ~(1UL << BH_New);
758 if (prev_bh) {
73516ace
FF		 759 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
760
761 if (tmp_next)
762 affs_warning(sb, "commit_write_ofs",
763 "next block already set for %d (%d)",
764 bidx, tmp_next);
1da177e4 765 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
73516ace 766 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
1da177e4
LT		 767 mark_buffer_dirty_inode(prev_bh, inode);
768 }
769 } else if (be32_to_cpu(AFFS_DATA_HEAD(bh)->size) < tmp)
770 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
771 affs_brelse(prev_bh);
772 affs_fix_checksum(sb, bh);
773 mark_buffer_dirty_inode(bh, inode);
774 written += tmp;
775 from += tmp;
776 bidx++;
777 }
778 SetPageUptodate(page);
779
780done:
781 affs_brelse(bh);
782 tmp = (page->index << PAGE_CACHE_SHIFT) + from;
783 if (tmp > inode->i_size)
784 inode->i_size = AFFS_I(inode)->mmu_private = tmp;
785
f2b6a16e
NP		 786 unlock_page(page);
787 page_cache_release(page);
788
1da177e4
LT		 789 return written;
790
791out:
792 bh = prev_bh;
793 if (!written)
794 written = PTR_ERR(bh);
795 goto done;
796}
797
f5e54d6e 798const struct address_space_operations affs_aops_ofs = {
1da177e4
LT		 799 .readpage = affs_readpage_ofs,
800 //.writepage = affs_writepage_ofs,
f2b6a16e
NP		 801 .write_begin = affs_write_begin_ofs,
802 .write_end = affs_write_end_ofs
1da177e4
LT		 803};
804
805/* Free any preallocated blocks. */
806
807void
808affs_free_prealloc(struct inode *inode)
809{
810 struct super_block *sb = inode->i_sb;
811
9606d9aa 812 pr_debug("free_prealloc(ino=%lu)\n", inode->i_ino);
1da177e4
LT		 813
814 while (AFFS_I(inode)->i_pa_cnt) {
815 AFFS_I(inode)->i_pa_cnt--;
816 affs_free_block(sb, ++AFFS_I(inode)->i_lastalloc);
817 }
818}
819
820/* Truncate (or enlarge) a file to the requested size. */
821
822void
823affs_truncate(struct inode *inode)
824{
825 struct super_block *sb = inode->i_sb;
826 u32 ext, ext_key;
827 u32 last_blk, blkcnt, blk;
828 u32 size;
829 struct buffer_head *ext_bh;
830 int i;
831
08fe100d
GU		 832 pr_debug("truncate(inode=%lu, oldsize=%llu, newsize=%llu)\n",
833 inode->i_ino, AFFS_I(inode)->mmu_private, inode->i_size);
1da177e4
LT		 834
835 last_blk = 0;
836 ext = 0;
837 if (inode->i_size) {
838 last_blk = ((u32)inode->i_size - 1) / AFFS_SB(sb)->s_data_blksize;
839 ext = last_blk / AFFS_SB(sb)->s_hashsize;
840 }
841
842 if (inode->i_size > AFFS_I(inode)->mmu_private) {
843 struct address_space *mapping = inode->i_mapping;
844 struct page *page;
f2b6a16e 845 void *fsdata;
73516ace 846 loff_t isize = inode->i_size;
1da177e4
LT		 847 int res;
848
73516ace 849 res = mapping->a_ops->write_begin(NULL, mapping, isize, 0, 0, &page, &fsdata);
1da177e4 850 if (!res)
73516ace 851 res = mapping->a_ops->write_end(NULL, mapping, isize, 0, 0, page, fsdata);
dca3c336
RZ		 852 else
853 inode->i_size = AFFS_I(inode)->mmu_private;
1da177e4
LT		 854 mark_inode_dirty(inode);
855 return;
856 } else if (inode->i_size == AFFS_I(inode)->mmu_private)
857 return;
858
859 // lock cache
860 ext_bh = affs_get_extblock(inode, ext);
861 if (IS_ERR(ext_bh)) {
1ee54b09
FF		 862 affs_warning(sb, "truncate",
863 "unexpected read error for ext block %u (%ld)",
08fe100d 864 ext, PTR_ERR(ext_bh));
1da177e4
LT		 865 return;
866 }
867 if (AFFS_I(inode)->i_lc) {
868 /* clear linear cache */
869 i = (ext + 1) >> AFFS_I(inode)->i_lc_shift;
870 if (AFFS_I(inode)->i_lc_size > i) {
871 AFFS_I(inode)->i_lc_size = i;
872 for (; i < AFFS_LC_SIZE; i++)
873 AFFS_I(inode)->i_lc[i] = 0;
874 }
875 /* clear associative cache */
876 for (i = 0; i < AFFS_AC_SIZE; i++)
877 if (AFFS_I(inode)->i_ac[i].ext >= ext)
878 AFFS_I(inode)->i_ac[i].ext = 0;
879 }
880 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
881
882 blkcnt = AFFS_I(inode)->i_blkcnt;
883 i = 0;
884 blk = last_blk;
885 if (inode->i_size) {
886 i = last_blk % AFFS_SB(sb)->s_hashsize + 1;
887 blk++;
888 } else
889 AFFS_HEAD(ext_bh)->first_data = 0;
dca3c336 890 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(i);
1da177e4
LT		 891 size = AFFS_SB(sb)->s_hashsize;
892 if (size > blkcnt - blk + i)
893 size = blkcnt - blk + i;
894 for (; i < size; i++, blk++) {
895 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
896 AFFS_BLOCK(sb, ext_bh, i) = 0;
897 }
898 AFFS_TAIL(sb, ext_bh)->extension = 0;
899 affs_fix_checksum(sb, ext_bh);
900 mark_buffer_dirty_inode(ext_bh, inode);
901 affs_brelse(ext_bh);
902
903 if (inode->i_size) {
904 AFFS_I(inode)->i_blkcnt = last_blk + 1;
905 AFFS_I(inode)->i_extcnt = ext + 1;
906 if (AFFS_SB(sb)->s_flags & SF_OFS) {
907 struct buffer_head *bh = affs_bread_ino(inode, last_blk, 0);
908 u32 tmp;
0e45b67d 909 if (IS_ERR(bh)) {
1ee54b09
FF		 910 affs_warning(sb, "truncate",
911 "unexpected read error for last block %u (%ld)",
08fe100d 912 ext, PTR_ERR(bh));
1da177e4
LT		 913 return;
914 }
915 tmp = be32_to_cpu(AFFS_DATA_HEAD(bh)->next);
916 AFFS_DATA_HEAD(bh)->next = 0;
917 affs_adjust_checksum(bh, -tmp);
918 affs_brelse(bh);
919 }
920 } else {
921 AFFS_I(inode)->i_blkcnt = 0;
922 AFFS_I(inode)->i_extcnt = 1;
923 }
924 AFFS_I(inode)->mmu_private = inode->i_size;
925 // unlock cache
926
927 while (ext_key) {
928 ext_bh = affs_bread(sb, ext_key);
929 size = AFFS_SB(sb)->s_hashsize;
930 if (size > blkcnt - blk)
931 size = blkcnt - blk;
932 for (i = 0; i < size; i++, blk++)
933 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
934 affs_free_block(sb, ext_key);
935 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
936 affs_brelse(ext_bh);
937 }
938 affs_free_prealloc(inode);
939}
c4758795 940
02c24a82 941int affs_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
c4758795 942{
7ea80859 943 struct inode *inode = filp->f_mapping->host;
c4758795
AV		 944 int ret, err;
945
02c24a82
JB		 946 err = filemap_write_and_wait_range(inode->i_mapping, start, end);
947 if (err)
948 return err;
949
950 mutex_lock(&inode->i_mutex);
c4758795
AV		 951 ret = write_inode_now(inode, 0);
952 err = sync_blockdev(inode->i_sb->s_bdev);
953 if (!ret)
954 ret = err;
02c24a82 955 mutex_unlock(&inode->i_mutex);
c4758795
AV		 956 return ret;
957}
7633978b
FF		 958const struct file_operations affs_file_operations = {
959 .llseek = generic_file_llseek,
960 .read = new_sync_read,
961 .read_iter = generic_file_read_iter,
962 .write = new_sync_write,
963 .write_iter = generic_file_write_iter,
964 .mmap = generic_file_mmap,
965 .open = affs_file_open,
966 .release = affs_file_release,
967 .fsync = affs_file_fsync,
968 .splice_read = generic_file_splice_read,
969};
970
971const struct inode_operations affs_file_inode_operations = {
972 .setattr = affs_notify_change,
973};
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