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Merge tag 'ktest-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux...
[linux.git] / fs / affs / file.c
CommitLineData
b2441318 1// SPDX-License-Identifier: GPL-2.0
1da177e4
LT		 2/*
3 * linux/fs/affs/file.c
4 *
5 * (c) 1996 Hans-Joachim Widmaier - Rewritten
6 *
7 * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.
8 *
9 * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem.
10 *
11 * (C) 1991 Linus Torvalds - minix filesystem
12 *
13 * affs regular file handling primitives
14 */
15
e2e40f2c 16#include <linux/uio.h>
3f1266f1 17#include <linux/blkdev.h>
1da177e4
LT		 18#include "affs.h"
19
1da177e4 20static struct buffer_head *affs_get_extblock_slow(struct inode *inode, u32 ext);
1da177e4
LT		 21
22static int
23affs_file_open(struct inode *inode, struct file *filp)
24{
9606d9aa 25 pr_debug("open(%lu,%d)\n",
dca3c336
RZ		 26 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
27 atomic_inc(&AFFS_I(inode)->i_opencnt);
1da177e4
LT		 28 return 0;
29}
30
31static int
32affs_file_release(struct inode *inode, struct file *filp)
33{
9606d9aa 34 pr_debug("release(%lu, %d)\n",
dca3c336
RZ		 35 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
36
37 if (atomic_dec_and_test(&AFFS_I(inode)->i_opencnt)) {
5955102c 38 inode_lock(inode);
dca3c336
RZ		 39 if (inode->i_size != AFFS_I(inode)->mmu_private)
40 affs_truncate(inode);
1da177e4 41 affs_free_prealloc(inode);
5955102c 42 inode_unlock(inode);
dca3c336 43 }
1da177e4
LT		 44
45 return 0;
46}
47
48static int
49affs_grow_extcache(struct inode *inode, u32 lc_idx)
50{
51 struct super_block *sb = inode->i_sb;
52 struct buffer_head *bh;
53 u32 lc_max;
54 int i, j, key;
55
56 if (!AFFS_I(inode)->i_lc) {
57 char *ptr = (char *)get_zeroed_page(GFP_NOFS);
58 if (!ptr)
59 return -ENOMEM;
60 AFFS_I(inode)->i_lc = (u32 *)ptr;
61 AFFS_I(inode)->i_ac = (struct affs_ext_key *)(ptr + AFFS_CACHE_SIZE / 2);
62 }
63
64 lc_max = AFFS_LC_SIZE << AFFS_I(inode)->i_lc_shift;
65
66 if (AFFS_I(inode)->i_extcnt > lc_max) {
67 u32 lc_shift, lc_mask, tmp, off;
68
69 /* need to recalculate linear cache, start from old size */
70 lc_shift = AFFS_I(inode)->i_lc_shift;
71 tmp = (AFFS_I(inode)->i_extcnt / AFFS_LC_SIZE) >> lc_shift;
72 for (; tmp; tmp >>= 1)
73 lc_shift++;
74 lc_mask = (1 << lc_shift) - 1;
75
76 /* fix idx and old size to new shift */
77 lc_idx >>= (lc_shift - AFFS_I(inode)->i_lc_shift);
78 AFFS_I(inode)->i_lc_size >>= (lc_shift - AFFS_I(inode)->i_lc_shift);
79
80 /* first shrink old cache to make more space */
81 off = 1 << (lc_shift - AFFS_I(inode)->i_lc_shift);
82 for (i = 1, j = off; j < AFFS_LC_SIZE; i++, j += off)
83 AFFS_I(inode)->i_ac[i] = AFFS_I(inode)->i_ac[j];
84
85 AFFS_I(inode)->i_lc_shift = lc_shift;
86 AFFS_I(inode)->i_lc_mask = lc_mask;
87 }
88
89 /* fill cache to the needed index */
90 i = AFFS_I(inode)->i_lc_size;
91 AFFS_I(inode)->i_lc_size = lc_idx + 1;
92 for (; i <= lc_idx; i++) {
93 if (!i) {
94 AFFS_I(inode)->i_lc[0] = inode->i_ino;
95 continue;
96 }
97 key = AFFS_I(inode)->i_lc[i - 1];
98 j = AFFS_I(inode)->i_lc_mask + 1;
99 // unlock cache
100 for (; j > 0; j--) {
101 bh = affs_bread(sb, key);
102 if (!bh)
103 goto err;
104 key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
105 affs_brelse(bh);
106 }
107 // lock cache
108 AFFS_I(inode)->i_lc[i] = key;
109 }
110
111 return 0;
112
113err:
114 // lock cache
115 return -EIO;
116}
117
118static struct buffer_head *
119affs_alloc_extblock(struct inode *inode, struct buffer_head *bh, u32 ext)
120{
121 struct super_block *sb = inode->i_sb;
122 struct buffer_head *new_bh;
123 u32 blocknr, tmp;
124
125 blocknr = affs_alloc_block(inode, bh->b_blocknr);
126 if (!blocknr)
127 return ERR_PTR(-ENOSPC);
128
129 new_bh = affs_getzeroblk(sb, blocknr);
130 if (!new_bh) {
131 affs_free_block(sb, blocknr);
132 return ERR_PTR(-EIO);
133 }
134
135 AFFS_HEAD(new_bh)->ptype = cpu_to_be32(T_LIST);
136 AFFS_HEAD(new_bh)->key = cpu_to_be32(blocknr);
137 AFFS_TAIL(sb, new_bh)->stype = cpu_to_be32(ST_FILE);
138 AFFS_TAIL(sb, new_bh)->parent = cpu_to_be32(inode->i_ino);
139 affs_fix_checksum(sb, new_bh);
140
141 mark_buffer_dirty_inode(new_bh, inode);
142
143 tmp = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
144 if (tmp)
145 affs_warning(sb, "alloc_ext", "previous extension set (%x)", tmp);
146 AFFS_TAIL(sb, bh)->extension = cpu_to_be32(blocknr);
147 affs_adjust_checksum(bh, blocknr - tmp);
148 mark_buffer_dirty_inode(bh, inode);
149
150 AFFS_I(inode)->i_extcnt++;
151 mark_inode_dirty(inode);
152
153 return new_bh;
154}
155
156static inline struct buffer_head *
157affs_get_extblock(struct inode *inode, u32 ext)
158{
159 /* inline the simplest case: same extended block as last time */
160 struct buffer_head *bh = AFFS_I(inode)->i_ext_bh;
161 if (ext == AFFS_I(inode)->i_ext_last)
dca3c336 162 get_bh(bh);
1da177e4
LT		 163 else
164 /* we have to do more (not inlined) */
165 bh = affs_get_extblock_slow(inode, ext);
166
167 return bh;
168}
169
170static struct buffer_head *
171affs_get_extblock_slow(struct inode *inode, u32 ext)
172{
173 struct super_block *sb = inode->i_sb;
174 struct buffer_head *bh;
175 u32 ext_key;
176 u32 lc_idx, lc_off, ac_idx;
177 u32 tmp, idx;
178
179 if (ext == AFFS_I(inode)->i_ext_last + 1) {
180 /* read the next extended block from the current one */
181 bh = AFFS_I(inode)->i_ext_bh;
182 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
183 if (ext < AFFS_I(inode)->i_extcnt)
184 goto read_ext;
afe305dc 185 BUG_ON(ext > AFFS_I(inode)->i_extcnt);
1da177e4
LT		 186 bh = affs_alloc_extblock(inode, bh, ext);
187 if (IS_ERR(bh))
188 return bh;
189 goto store_ext;
190 }
191
192 if (ext == 0) {
193 /* we seek back to the file header block */
194 ext_key = inode->i_ino;
195 goto read_ext;
196 }
197
198 if (ext >= AFFS_I(inode)->i_extcnt) {
199 struct buffer_head *prev_bh;
200
201 /* allocate a new extended block */
afe305dc 202 BUG_ON(ext > AFFS_I(inode)->i_extcnt);
1da177e4
LT		 203
204 /* get previous extended block */
205 prev_bh = affs_get_extblock(inode, ext - 1);
206 if (IS_ERR(prev_bh))
207 return prev_bh;
208 bh = affs_alloc_extblock(inode, prev_bh, ext);
209 affs_brelse(prev_bh);
210 if (IS_ERR(bh))
211 return bh;
212 goto store_ext;
213 }
214
215again:
216 /* check if there is an extended cache and whether it's large enough */
217 lc_idx = ext >> AFFS_I(inode)->i_lc_shift;
218 lc_off = ext & AFFS_I(inode)->i_lc_mask;
219
220 if (lc_idx >= AFFS_I(inode)->i_lc_size) {
221 int err;
222
223 err = affs_grow_extcache(inode, lc_idx);
224 if (err)
225 return ERR_PTR(err);
226 goto again;
227 }
228
229 /* every n'th key we find in the linear cache */
230 if (!lc_off) {
231 ext_key = AFFS_I(inode)->i_lc[lc_idx];
232 goto read_ext;
233 }
234
235 /* maybe it's still in the associative cache */
236 ac_idx = (ext - lc_idx - 1) & AFFS_AC_MASK;
237 if (AFFS_I(inode)->i_ac[ac_idx].ext == ext) {
238 ext_key = AFFS_I(inode)->i_ac[ac_idx].key;
239 goto read_ext;
240 }
241
242 /* try to find one of the previous extended blocks */
243 tmp = ext;
244 idx = ac_idx;
245 while (--tmp, --lc_off > 0) {
246 idx = (idx - 1) & AFFS_AC_MASK;
247 if (AFFS_I(inode)->i_ac[idx].ext == tmp) {
248 ext_key = AFFS_I(inode)->i_ac[idx].key;
249 goto find_ext;
250 }
251 }
252
253 /* fall back to the linear cache */
254 ext_key = AFFS_I(inode)->i_lc[lc_idx];
255find_ext:
256 /* read all extended blocks until we find the one we need */
257 //unlock cache
258 do {
259 bh = affs_bread(sb, ext_key);
260 if (!bh)
261 goto err_bread;
262 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
263 affs_brelse(bh);
264 tmp++;
265 } while (tmp < ext);
266 //lock cache
267
268 /* store it in the associative cache */
269 // recalculate ac_idx?
270 AFFS_I(inode)->i_ac[ac_idx].ext = ext;
271 AFFS_I(inode)->i_ac[ac_idx].key = ext_key;
272
273read_ext:
274 /* finally read the right extended block */
275 //unlock cache
276 bh = affs_bread(sb, ext_key);
277 if (!bh)
278 goto err_bread;
279 //lock cache
280
281store_ext:
282 /* release old cached extended block and store the new one */
283 affs_brelse(AFFS_I(inode)->i_ext_bh);
284 AFFS_I(inode)->i_ext_last = ext;
285 AFFS_I(inode)->i_ext_bh = bh;
dca3c336 286 get_bh(bh);
1da177e4
LT		 287
288 return bh;
289
290err_bread:
291 affs_brelse(bh);
292 return ERR_PTR(-EIO);
293}
294
295static int
296affs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh_result, int create)
297{
298 struct super_block *sb = inode->i_sb;
299 struct buffer_head *ext_bh;
300 u32 ext;
301
08fe100d
GU		 302 pr_debug("%s(%lu, %llu)\n", __func__, inode->i_ino,
303 (unsigned long long)block);
1da177e4 304
8d4b6900 305 BUG_ON(block > (sector_t)0x7fffffffUL);
1da177e4
LT		 306
307 if (block >= AFFS_I(inode)->i_blkcnt) {
308 if (block > AFFS_I(inode)->i_blkcnt || !create)
309 goto err_big;
310 } else
311 create = 0;
312
313 //lock cache
314 affs_lock_ext(inode);
315
316 ext = (u32)block / AFFS_SB(sb)->s_hashsize;
317 block -= ext * AFFS_SB(sb)->s_hashsize;
318 ext_bh = affs_get_extblock(inode, ext);
319 if (IS_ERR(ext_bh))
320 goto err_ext;
321 map_bh(bh_result, sb, (sector_t)be32_to_cpu(AFFS_BLOCK(sb, ext_bh, block)));
322
323 if (create) {
324 u32 blocknr = affs_alloc_block(inode, ext_bh->b_blocknr);
325 if (!blocknr)
326 goto err_alloc;
327 set_buffer_new(bh_result);
328 AFFS_I(inode)->mmu_private += AFFS_SB(sb)->s_data_blksize;
329 AFFS_I(inode)->i_blkcnt++;
330
331 /* store new block */
332 if (bh_result->b_blocknr)
08fe100d
GU		 333 affs_warning(sb, "get_block",
334 "block already set (%llx)",
335 (unsigned long long)bh_result->b_blocknr);
1da177e4
LT		 336 AFFS_BLOCK(sb, ext_bh, block) = cpu_to_be32(blocknr);
337 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(block + 1);
338 affs_adjust_checksum(ext_bh, blocknr - bh_result->b_blocknr + 1);
339 bh_result->b_blocknr = blocknr;
340
341 if (!block) {
342 /* insert first block into header block */
343 u32 tmp = be32_to_cpu(AFFS_HEAD(ext_bh)->first_data);
344 if (tmp)
345 affs_warning(sb, "get_block", "first block already set (%d)", tmp);
346 AFFS_HEAD(ext_bh)->first_data = cpu_to_be32(blocknr);
347 affs_adjust_checksum(ext_bh, blocknr - tmp);
348 }
349 }
350
351 affs_brelse(ext_bh);
352 //unlock cache
353 affs_unlock_ext(inode);
354 return 0;
355
356err_big:
08fe100d
GU		 357 affs_error(inode->i_sb, "get_block", "strange block request %llu",
358 (unsigned long long)block);
1da177e4
LT		 359 return -EIO;
360err_ext:
361 // unlock cache
362 affs_unlock_ext(inode);
363 return PTR_ERR(ext_bh);
364err_alloc:
365 brelse(ext_bh);
366 clear_buffer_mapped(bh_result);
367 bh_result->b_bdev = NULL;
368 // unlock cache
369 affs_unlock_ext(inode);
370 return -ENOSPC;
371}
372
373static int affs_writepage(struct page *page, struct writeback_control *wbc)
374{
375 return block_write_full_page(page, affs_get_block, wbc);
376}
f2b6a16e 377
1da177e4
LT		 378static int affs_readpage(struct file *file, struct page *page)
379{
380 return block_read_full_page(page, affs_get_block);
381}
f2b6a16e 382
1dc1834f
MS		 383static void affs_write_failed(struct address_space *mapping, loff_t to)
384{
385 struct inode *inode = mapping->host;
386
387 if (to > inode->i_size) {
7caef267 388 truncate_pagecache(inode, inode->i_size);
1dc1834f
MS		 389 affs_truncate(inode);
390 }
391}
392
9abb4083 393static ssize_t
c8b8e32d 394affs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
9abb4083
FF		 395{
396 struct file *file = iocb->ki_filp;
397 struct address_space *mapping = file->f_mapping;
398 struct inode *inode = mapping->host;
399 size_t count = iov_iter_count(iter);
c8b8e32d 400 loff_t offset = iocb->ki_pos;
9abb4083
FF		 401 ssize_t ret;
402
6f673763 403 if (iov_iter_rw(iter) == WRITE) {
92b20708
FF		 404 loff_t size = offset + count;
405
406 if (AFFS_I(inode)->mmu_private < size)
407 return 0;
408 }
409
c8b8e32d 410 ret = blockdev_direct_IO(iocb, inode, iter, affs_get_block);
6f673763 411 if (ret < 0 && iov_iter_rw(iter) == WRITE)
9abb4083
FF		 412 affs_write_failed(mapping, offset + count);
413 return ret;
414}
415
f2b6a16e
NP		 416static int affs_write_begin(struct file *file, struct address_space *mapping,
417 loff_t pos, unsigned len, unsigned flags,
418 struct page **pagep, void **fsdata)
1da177e4 419{
282dc178
CH		 420 int ret;
421
f2b6a16e 422 *pagep = NULL;
282dc178 423 ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
f2b6a16e
NP		 424 affs_get_block,
425 &AFFS_I(mapping->host)->mmu_private);
1dc1834f
MS		 426 if (unlikely(ret))
427 affs_write_failed(mapping, pos + len);
282dc178
CH		 428
429 return ret;
1da177e4 430}
f2b6a16e 431
1da177e4
LT		 432static sector_t _affs_bmap(struct address_space *mapping, sector_t block)
433{
434 return generic_block_bmap(mapping,block,affs_get_block);
435}
f2b6a16e 436
f5e54d6e 437const struct address_space_operations affs_aops = {
1da177e4
LT		 438 .readpage = affs_readpage,
439 .writepage = affs_writepage,
f2b6a16e
NP		 440 .write_begin = affs_write_begin,
441 .write_end = generic_write_end,
9abb4083 442 .direct_IO = affs_direct_IO,
1da177e4
LT		 443 .bmap = _affs_bmap
444};
445
446static inline struct buffer_head *
447affs_bread_ino(struct inode *inode, int block, int create)
448{
449 struct buffer_head *bh, tmp_bh;
450 int err;
451
452 tmp_bh.b_state = 0;
453 err = affs_get_block(inode, block, &tmp_bh, create);
454 if (!err) {
455 bh = affs_bread(inode->i_sb, tmp_bh.b_blocknr);
456 if (bh) {
457 bh->b_state |= tmp_bh.b_state;
458 return bh;
459 }
460 err = -EIO;
461 }
462 return ERR_PTR(err);
463}
464
465static inline struct buffer_head *
466affs_getzeroblk_ino(struct inode *inode, int block)
467{
468 struct buffer_head *bh, tmp_bh;
469 int err;
470
471 tmp_bh.b_state = 0;
472 err = affs_get_block(inode, block, &tmp_bh, 1);
473 if (!err) {
474 bh = affs_getzeroblk(inode->i_sb, tmp_bh.b_blocknr);
475 if (bh) {
476 bh->b_state |= tmp_bh.b_state;
477 return bh;
478 }
479 err = -EIO;
480 }
481 return ERR_PTR(err);
482}
483
484static inline struct buffer_head *
485affs_getemptyblk_ino(struct inode *inode, int block)
486{
487 struct buffer_head *bh, tmp_bh;
488 int err;
489
490 tmp_bh.b_state = 0;
491 err = affs_get_block(inode, block, &tmp_bh, 1);
492 if (!err) {
493 bh = affs_getemptyblk(inode->i_sb, tmp_bh.b_blocknr);
494 if (bh) {
495 bh->b_state |= tmp_bh.b_state;
496 return bh;
497 }
498 err = -EIO;
499 }
500 return ERR_PTR(err);
501}
502
1da177e4 503static int
077e073e 504affs_do_readpage_ofs(struct page *page, unsigned to, int create)
1da177e4
LT		 505{
506 struct inode *inode = page->mapping->host;
507 struct super_block *sb = inode->i_sb;
508 struct buffer_head *bh;
509 char *data;
0c89d670 510 unsigned pos = 0;
1da177e4
LT		 511 u32 bidx, boff, bsize;
512 u32 tmp;
513
08fe100d 514 pr_debug("%s(%lu, %ld, 0, %d)\n", __func__, inode->i_ino,
0c89d670 515 page->index, to);
09cbfeaf 516 BUG_ON(to > PAGE_SIZE);
1da177e4 517 bsize = AFFS_SB(sb)->s_data_blksize;
09cbfeaf 518 tmp = page->index << PAGE_SHIFT;
1da177e4
LT		 519 bidx = tmp / bsize;
520 boff = tmp % bsize;
521
0c89d670 522 while (pos < to) {
077e073e 523 bh = affs_bread_ino(inode, bidx, create);
1da177e4
LT		 524 if (IS_ERR(bh))
525 return PTR_ERR(bh);
0c89d670
FF		 526 tmp = min(bsize - boff, to - pos);
527 BUG_ON(pos + tmp > to || tmp > bsize);
0bacbe52 528 data = kmap_atomic(page);
0c89d670 529 memcpy(data + pos, AFFS_DATA(bh) + boff, tmp);
0bacbe52 530 kunmap_atomic(data);
1da177e4
LT		 531 affs_brelse(bh);
532 bidx++;
0c89d670 533 pos += tmp;
1da177e4
LT		 534 boff = 0;
535 }
536 flush_dcache_page(page);
1da177e4
LT		 537 return 0;
538}
539
540static int
541affs_extent_file_ofs(struct inode *inode, u32 newsize)
542{
543 struct super_block *sb = inode->i_sb;
544 struct buffer_head *bh, *prev_bh;
545 u32 bidx, boff;
546 u32 size, bsize;
547 u32 tmp;
548
08fe100d 549 pr_debug("%s(%lu, %d)\n", __func__, inode->i_ino, newsize);
1da177e4
LT		 550 bsize = AFFS_SB(sb)->s_data_blksize;
551 bh = NULL;
552 size = AFFS_I(inode)->mmu_private;
553 bidx = size / bsize;
554 boff = size % bsize;
555 if (boff) {
556 bh = affs_bread_ino(inode, bidx, 0);
557 if (IS_ERR(bh))
558 return PTR_ERR(bh);
559 tmp = min(bsize - boff, newsize - size);
8d4b6900 560 BUG_ON(boff + tmp > bsize || tmp > bsize);
1da177e4 561 memset(AFFS_DATA(bh) + boff, 0, tmp);
6369a4ab 562 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp);
1da177e4
LT		 563 affs_fix_checksum(sb, bh);
564 mark_buffer_dirty_inode(bh, inode);
565 size += tmp;
566 bidx++;
567 } else if (bidx) {
568 bh = affs_bread_ino(inode, bidx - 1, 0);
569 if (IS_ERR(bh))
570 return PTR_ERR(bh);
571 }
572
573 while (size < newsize) {
574 prev_bh = bh;
575 bh = affs_getzeroblk_ino(inode, bidx);
576 if (IS_ERR(bh))
577 goto out;
578 tmp = min(bsize, newsize - size);
8d4b6900 579 BUG_ON(tmp > bsize);
1da177e4
LT		 580 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
581 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
582 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
583 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
584 affs_fix_checksum(sb, bh);
585 bh->b_state &= ~(1UL << BH_New);
586 mark_buffer_dirty_inode(bh, inode);
587 if (prev_bh) {
73516ace
FF		 588 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
589
590 if (tmp_next)
591 affs_warning(sb, "extent_file_ofs",
592 "next block already set for %d (%d)",
593 bidx, tmp_next);
1da177e4 594 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
73516ace 595 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
1da177e4
LT		 596 mark_buffer_dirty_inode(prev_bh, inode);
597 affs_brelse(prev_bh);
598 }
599 size += bsize;
600 bidx++;
601 }
602 affs_brelse(bh);
603 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
604 return 0;
605
606out:
607 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
608 return PTR_ERR(bh);
609}
610
611static int
612affs_readpage_ofs(struct file *file, struct page *page)
613{
614 struct inode *inode = page->mapping->host;
615 u32 to;
616 int err;
617
08fe100d 618 pr_debug("%s(%lu, %ld)\n", __func__, inode->i_ino, page->index);
09cbfeaf
KS		 619 to = PAGE_SIZE;
620 if (((page->index + 1) << PAGE_SHIFT) > inode->i_size) {
621 to = inode->i_size & ~PAGE_MASK;
622 memset(page_address(page) + to, 0, PAGE_SIZE - to);
1da177e4
LT		 623 }
624
077e073e 625 err = affs_do_readpage_ofs(page, to, 0);
1da177e4
LT		 626 if (!err)
627 SetPageUptodate(page);
628 unlock_page(page);
629 return err;
630}
631
f2b6a16e
NP		 632static int affs_write_begin_ofs(struct file *file, struct address_space *mapping,
633 loff_t pos, unsigned len, unsigned flags,
634 struct page **pagep, void **fsdata)
1da177e4 635{
f2b6a16e
NP		 636 struct inode *inode = mapping->host;
637 struct page *page;
638 pgoff_t index;
1da177e4
LT		 639 int err = 0;
640
08fe100d
GU		 641 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos,
642 pos + len);
f2b6a16e
NP		 643 if (pos > AFFS_I(inode)->mmu_private) {
644 /* XXX: this probably leaves a too-big i_size in case of
645 * failure. Should really be updating i_size at write_end time
646 */
647 err = affs_extent_file_ofs(inode, pos);
1da177e4
LT		 648 if (err)
649 return err;
650 }
f2b6a16e 651
09cbfeaf 652 index = pos >> PAGE_SHIFT;
54566b2c 653 page = grab_cache_page_write_begin(mapping, index, flags);
f2b6a16e
NP		 654 if (!page)
655 return -ENOMEM;
656 *pagep = page;
1da177e4
LT		 657
658 if (PageUptodate(page))
659 return 0;
660
f2b6a16e 661 /* XXX: inefficient but safe in the face of short writes */
077e073e 662 err = affs_do_readpage_ofs(page, PAGE_SIZE, 1);
f2b6a16e
NP		 663 if (err) {
664 unlock_page(page);
09cbfeaf 665 put_page(page);
1da177e4
LT		 666 }
667 return err;
668}
669
f2b6a16e
NP		 670static int affs_write_end_ofs(struct file *file, struct address_space *mapping,
671 loff_t pos, unsigned len, unsigned copied,
672 struct page *page, void *fsdata)
1da177e4 673{
f2b6a16e 674 struct inode *inode = mapping->host;
1da177e4
LT		 675 struct super_block *sb = inode->i_sb;
676 struct buffer_head *bh, *prev_bh;
677 char *data;
678 u32 bidx, boff, bsize;
f2b6a16e 679 unsigned from, to;
1da177e4
LT		 680 u32 tmp;
681 int written;
682
09cbfeaf 683 from = pos & (PAGE_SIZE - 1);
a80f2d22 684 to = from + len;
f2b6a16e
NP		 685 /*
686 * XXX: not sure if this can handle short copies (len < copied), but
687 * we don't have to, because the page should always be uptodate here,
688 * due to write_begin.
689 */
690
08fe100d
GU		 691 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos,
692 pos + len);
1da177e4
LT		 693 bsize = AFFS_SB(sb)->s_data_blksize;
694 data = page_address(page);
695
696 bh = NULL;
697 written = 0;
09cbfeaf 698 tmp = (page->index << PAGE_SHIFT) + from;
1da177e4
LT		 699 bidx = tmp / bsize;
700 boff = tmp % bsize;
701 if (boff) {
702 bh = affs_bread_ino(inode, bidx, 0);
3d5d472c
TK		 703 if (IS_ERR(bh)) {
704 written = PTR_ERR(bh);
705 goto err_first_bh;
706 }
1da177e4 707 tmp = min(bsize - boff, to - from);
8d4b6900 708 BUG_ON(boff + tmp > bsize || tmp > bsize);
1da177e4 709 memcpy(AFFS_DATA(bh) + boff, data + from, tmp);
6369a4ab 710 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp);
1da177e4
LT		 711 affs_fix_checksum(sb, bh);
712 mark_buffer_dirty_inode(bh, inode);
713 written += tmp;
714 from += tmp;
715 bidx++;
716 } else if (bidx) {
717 bh = affs_bread_ino(inode, bidx - 1, 0);
3d5d472c
TK		 718 if (IS_ERR(bh)) {
719 written = PTR_ERR(bh);
720 goto err_first_bh;
721 }
1da177e4
LT		 722 }
723 while (from + bsize <= to) {
724 prev_bh = bh;
725 bh = affs_getemptyblk_ino(inode, bidx);
726 if (IS_ERR(bh))
3d5d472c 727 goto err_bh;
1da177e4
LT		 728 memcpy(AFFS_DATA(bh), data + from, bsize);
729 if (buffer_new(bh)) {
730 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
731 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
732 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
733 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(bsize);
734 AFFS_DATA_HEAD(bh)->next = 0;
735 bh->b_state &= ~(1UL << BH_New);
736 if (prev_bh) {
73516ace
FF		 737 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
738
739 if (tmp_next)
740 affs_warning(sb, "commit_write_ofs",
741 "next block already set for %d (%d)",
742 bidx, tmp_next);
1da177e4 743 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
73516ace 744 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
1da177e4
LT		 745 mark_buffer_dirty_inode(prev_bh, inode);
746 }
747 }
748 affs_brelse(prev_bh);
749 affs_fix_checksum(sb, bh);
750 mark_buffer_dirty_inode(bh, inode);
751 written += bsize;
752 from += bsize;
753 bidx++;
754 }
755 if (from < to) {
756 prev_bh = bh;
757 bh = affs_bread_ino(inode, bidx, 1);
758 if (IS_ERR(bh))
3d5d472c 759 goto err_bh;
1da177e4 760 tmp = min(bsize, to - from);
8d4b6900 761 BUG_ON(tmp > bsize);
1da177e4
LT		 762 memcpy(AFFS_DATA(bh), data + from, tmp);
763 if (buffer_new(bh)) {
764 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
765 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
766 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
767 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
768 AFFS_DATA_HEAD(bh)->next = 0;
769 bh->b_state &= ~(1UL << BH_New);
770 if (prev_bh) {
73516ace
FF		 771 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
772
773 if (tmp_next)
774 affs_warning(sb, "commit_write_ofs",
775 "next block already set for %d (%d)",
776 bidx, tmp_next);
1da177e4 777 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
73516ace 778 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
1da177e4
LT		 779 mark_buffer_dirty_inode(prev_bh, inode);
780 }
781 } else if (be32_to_cpu(AFFS_DATA_HEAD(bh)->size) < tmp)
782 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
783 affs_brelse(prev_bh);
784 affs_fix_checksum(sb, bh);
785 mark_buffer_dirty_inode(bh, inode);
786 written += tmp;
787 from += tmp;
788 bidx++;
789 }
790 SetPageUptodate(page);
791
792done:
793 affs_brelse(bh);
09cbfeaf 794 tmp = (page->index << PAGE_SHIFT) + from;
1da177e4
LT		 795 if (tmp > inode->i_size)
796 inode->i_size = AFFS_I(inode)->mmu_private = tmp;
797
3d5d472c 798err_first_bh:
f2b6a16e 799 unlock_page(page);
09cbfeaf 800 put_page(page);
f2b6a16e 801
1da177e4
LT		 802 return written;
803
3d5d472c 804err_bh:
1da177e4
LT		 805 bh = prev_bh;
806 if (!written)
807 written = PTR_ERR(bh);
808 goto done;
809}
810
f5e54d6e 811const struct address_space_operations affs_aops_ofs = {
1da177e4
LT		 812 .readpage = affs_readpage_ofs,
813 //.writepage = affs_writepage_ofs,
f2b6a16e
NP		 814 .write_begin = affs_write_begin_ofs,
815 .write_end = affs_write_end_ofs
1da177e4
LT		 816};
817
818/* Free any preallocated blocks. */
819
820void
821affs_free_prealloc(struct inode *inode)
822{
823 struct super_block *sb = inode->i_sb;
824
9606d9aa 825 pr_debug("free_prealloc(ino=%lu)\n", inode->i_ino);
1da177e4
LT		 826
827 while (AFFS_I(inode)->i_pa_cnt) {
828 AFFS_I(inode)->i_pa_cnt--;
829 affs_free_block(sb, ++AFFS_I(inode)->i_lastalloc);
830 }
831}
832
833/* Truncate (or enlarge) a file to the requested size. */
834
835void
836affs_truncate(struct inode *inode)
837{
838 struct super_block *sb = inode->i_sb;
839 u32 ext, ext_key;
840 u32 last_blk, blkcnt, blk;
841 u32 size;
842 struct buffer_head *ext_bh;
843 int i;
844
08fe100d
GU		 845 pr_debug("truncate(inode=%lu, oldsize=%llu, newsize=%llu)\n",
846 inode->i_ino, AFFS_I(inode)->mmu_private, inode->i_size);
1da177e4
LT		 847
848 last_blk = 0;
849 ext = 0;
850 if (inode->i_size) {
851 last_blk = ((u32)inode->i_size - 1) / AFFS_SB(sb)->s_data_blksize;
852 ext = last_blk / AFFS_SB(sb)->s_hashsize;
853 }
854
855 if (inode->i_size > AFFS_I(inode)->mmu_private) {
856 struct address_space *mapping = inode->i_mapping;
857 struct page *page;
f2b6a16e 858 void *fsdata;
73516ace 859 loff_t isize = inode->i_size;
1da177e4
LT		 860 int res;
861
73516ace 862 res = mapping->a_ops->write_begin(NULL, mapping, isize, 0, 0, &page, &fsdata);
1da177e4 863 if (!res)
73516ace 864 res = mapping->a_ops->write_end(NULL, mapping, isize, 0, 0, page, fsdata);
dca3c336
RZ		 865 else
866 inode->i_size = AFFS_I(inode)->mmu_private;
1da177e4
LT		 867 mark_inode_dirty(inode);
868 return;
869 } else if (inode->i_size == AFFS_I(inode)->mmu_private)
870 return;
871
872 // lock cache
873 ext_bh = affs_get_extblock(inode, ext);
874 if (IS_ERR(ext_bh)) {
1ee54b09
FF		 875 affs_warning(sb, "truncate",
876 "unexpected read error for ext block %u (%ld)",
08fe100d 877 ext, PTR_ERR(ext_bh));
1da177e4
LT		 878 return;
879 }
880 if (AFFS_I(inode)->i_lc) {
881 /* clear linear cache */
882 i = (ext + 1) >> AFFS_I(inode)->i_lc_shift;
883 if (AFFS_I(inode)->i_lc_size > i) {
884 AFFS_I(inode)->i_lc_size = i;
885 for (; i < AFFS_LC_SIZE; i++)
886 AFFS_I(inode)->i_lc[i] = 0;
887 }
888 /* clear associative cache */
889 for (i = 0; i < AFFS_AC_SIZE; i++)
890 if (AFFS_I(inode)->i_ac[i].ext >= ext)
891 AFFS_I(inode)->i_ac[i].ext = 0;
892 }
893 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
894
895 blkcnt = AFFS_I(inode)->i_blkcnt;
896 i = 0;
897 blk = last_blk;
898 if (inode->i_size) {
899 i = last_blk % AFFS_SB(sb)->s_hashsize + 1;
900 blk++;
901 } else
902 AFFS_HEAD(ext_bh)->first_data = 0;
dca3c336 903 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(i);
1da177e4
LT		 904 size = AFFS_SB(sb)->s_hashsize;
905 if (size > blkcnt - blk + i)
906 size = blkcnt - blk + i;
907 for (; i < size; i++, blk++) {
908 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
909 AFFS_BLOCK(sb, ext_bh, i) = 0;
910 }
911 AFFS_TAIL(sb, ext_bh)->extension = 0;
912 affs_fix_checksum(sb, ext_bh);
913 mark_buffer_dirty_inode(ext_bh, inode);
914 affs_brelse(ext_bh);
915
916 if (inode->i_size) {
917 AFFS_I(inode)->i_blkcnt = last_blk + 1;
918 AFFS_I(inode)->i_extcnt = ext + 1;
79bda4d5 919 if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_OFS)) {
1da177e4
LT		 920 struct buffer_head *bh = affs_bread_ino(inode, last_blk, 0);
921 u32 tmp;
0e45b67d 922 if (IS_ERR(bh)) {
1ee54b09
FF		 923 affs_warning(sb, "truncate",
924 "unexpected read error for last block %u (%ld)",
08fe100d 925 ext, PTR_ERR(bh));
1da177e4
LT		 926 return;
927 }
928 tmp = be32_to_cpu(AFFS_DATA_HEAD(bh)->next);
929 AFFS_DATA_HEAD(bh)->next = 0;
930 affs_adjust_checksum(bh, -tmp);
931 affs_brelse(bh);
932 }
933 } else {
934 AFFS_I(inode)->i_blkcnt = 0;
935 AFFS_I(inode)->i_extcnt = 1;
936 }
937 AFFS_I(inode)->mmu_private = inode->i_size;
938 // unlock cache
939
940 while (ext_key) {
941 ext_bh = affs_bread(sb, ext_key);
942 size = AFFS_SB(sb)->s_hashsize;
943 if (size > blkcnt - blk)
944 size = blkcnt - blk;
945 for (i = 0; i < size; i++, blk++)
946 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
947 affs_free_block(sb, ext_key);
948 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
949 affs_brelse(ext_bh);
950 }
951 affs_free_prealloc(inode);
952}
c4758795 953
02c24a82 954int affs_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
c4758795 955{
7ea80859 956 struct inode *inode = filp->f_mapping->host;
c4758795
AV		 957 int ret, err;
958
3b49c9a1 959 err = file_write_and_wait_range(filp, start, end);
02c24a82
JB		 960 if (err)
961 return err;
962
5955102c 963 inode_lock(inode);
c4758795
AV		 964 ret = write_inode_now(inode, 0);
965 err = sync_blockdev(inode->i_sb->s_bdev);
966 if (!ret)
967 ret = err;
5955102c 968 inode_unlock(inode);
c4758795
AV		 969 return ret;
970}
7633978b
FF		 971const struct file_operations affs_file_operations = {
972 .llseek = generic_file_llseek,
7633978b 973 .read_iter = generic_file_read_iter,
7633978b
FF		 974 .write_iter = generic_file_write_iter,
975 .mmap = generic_file_mmap,
976 .open = affs_file_open,
977 .release = affs_file_release,
978 .fsync = affs_file_fsync,
979 .splice_read = generic_file_splice_read,
980};
981
982const struct inode_operations affs_file_inode_operations = {
983 .setattr = affs_notify_change,
984};
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