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Merge tag 'block-5.9-2020-09-22' of git://git.kernel.dk/linux-block
[mirror_ubuntu-jammy-kernel.git] / fs / affs / file.c
1 // SPDX-License-Identifier: GPL-2.0
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
16 #include <linux/uio.h>
17 #include <linux/blkdev.h>
18 #include "affs.h"
19
20 static struct buffer_head *affs_get_extblock_slow(struct inode *inode, u32 ext);
21
22 static int
23 affs_file_open(struct inode *inode, struct file *filp)
24 {
25 pr_debug("open(%lu,%d)\n",
26 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
27 atomic_inc(&AFFS_I(inode)->i_opencnt);
28 return 0;
29 }
30
31 static int
32 affs_file_release(struct inode *inode, struct file *filp)
33 {
34 pr_debug("release(%lu, %d)\n",
35 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
36
37 if (atomic_dec_and_test(&AFFS_I(inode)->i_opencnt)) {
38 inode_lock(inode);
39 if (inode->i_size != AFFS_I(inode)->mmu_private)
40 affs_truncate(inode);
41 affs_free_prealloc(inode);
42 inode_unlock(inode);
43 }
44
45 return 0;
46 }
47
48 static int
49 affs_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
113 err:
114 // lock cache
115 return -EIO;
116 }
117
118 static struct buffer_head *
119 affs_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
156 static inline struct buffer_head *
157 affs_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)
162 get_bh(bh);
163 else
164 /* we have to do more (not inlined) */
165 bh = affs_get_extblock_slow(inode, ext);
166
167 return bh;
168 }
169
170 static struct buffer_head *
171 affs_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;
185 BUG_ON(ext > AFFS_I(inode)->i_extcnt);
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 */
202 BUG_ON(ext > AFFS_I(inode)->i_extcnt);
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
215 again:
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];
255 find_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
273 read_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
281 store_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;
286 get_bh(bh);
287
288 return bh;
289
290 err_bread:
291 affs_brelse(bh);
292 return ERR_PTR(-EIO);
293 }
294
295 static int
296 affs_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
302 pr_debug("%s(%lu, %llu)\n", __func__, inode->i_ino,
303 (unsigned long long)block);
304
305 BUG_ON(block > (sector_t)0x7fffffffUL);
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)
333 affs_warning(sb, "get_block",
334 "block already set (%llx)",
335 (unsigned long long)bh_result->b_blocknr);
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
356 err_big:
357 affs_error(inode->i_sb, "get_block", "strange block request %llu",
358 (unsigned long long)block);
359 return -EIO;
360 err_ext:
361 // unlock cache
362 affs_unlock_ext(inode);
363 return PTR_ERR(ext_bh);
364 err_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
373 static int affs_writepage(struct page *page, struct writeback_control *wbc)
374 {
375 return block_write_full_page(page, affs_get_block, wbc);
376 }
377
378 static int affs_readpage(struct file *file, struct page *page)
379 {
380 return block_read_full_page(page, affs_get_block);
381 }
382
383 static 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) {
388 truncate_pagecache(inode, inode->i_size);
389 affs_truncate(inode);
390 }
391 }
392
393 static ssize_t
394 affs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
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);
400 loff_t offset = iocb->ki_pos;
401 ssize_t ret;
402
403 if (iov_iter_rw(iter) == WRITE) {
404 loff_t size = offset + count;
405
406 if (AFFS_I(inode)->mmu_private < size)
407 return 0;
408 }
409
410 ret = blockdev_direct_IO(iocb, inode, iter, affs_get_block);
411 if (ret < 0 && iov_iter_rw(iter) == WRITE)
412 affs_write_failed(mapping, offset + count);
413 return ret;
414 }
415
416 static 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)
419 {
420 int ret;
421
422 *pagep = NULL;
423 ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
424 affs_get_block,
425 &AFFS_I(mapping->host)->mmu_private);
426 if (unlikely(ret))
427 affs_write_failed(mapping, pos + len);
428
429 return ret;
430 }
431
432 static int affs_write_end(struct file *file, struct address_space *mapping,
433 loff_t pos, unsigned int len, unsigned int copied,
434 struct page *page, void *fsdata)
435 {
436 struct inode *inode = mapping->host;
437 int ret;
438
439 ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
440
441 /* Clear Archived bit on file writes, as AmigaOS would do */
442 if (AFFS_I(inode)->i_protect & FIBF_ARCHIVED) {
443 AFFS_I(inode)->i_protect &= ~FIBF_ARCHIVED;
444 mark_inode_dirty(inode);
445 }
446
447 return ret;
448 }
449
450 static sector_t _affs_bmap(struct address_space *mapping, sector_t block)
451 {
452 return generic_block_bmap(mapping,block,affs_get_block);
453 }
454
455 const struct address_space_operations affs_aops = {
456 .readpage = affs_readpage,
457 .writepage = affs_writepage,
458 .write_begin = affs_write_begin,
459 .write_end = affs_write_end,
460 .direct_IO = affs_direct_IO,
461 .bmap = _affs_bmap
462 };
463
464 static inline struct buffer_head *
465 affs_bread_ino(struct inode *inode, int block, int create)
466 {
467 struct buffer_head *bh, tmp_bh;
468 int err;
469
470 tmp_bh.b_state = 0;
471 err = affs_get_block(inode, block, &tmp_bh, create);
472 if (!err) {
473 bh = affs_bread(inode->i_sb, tmp_bh.b_blocknr);
474 if (bh) {
475 bh->b_state |= tmp_bh.b_state;
476 return bh;
477 }
478 err = -EIO;
479 }
480 return ERR_PTR(err);
481 }
482
483 static inline struct buffer_head *
484 affs_getzeroblk_ino(struct inode *inode, int block)
485 {
486 struct buffer_head *bh, tmp_bh;
487 int err;
488
489 tmp_bh.b_state = 0;
490 err = affs_get_block(inode, block, &tmp_bh, 1);
491 if (!err) {
492 bh = affs_getzeroblk(inode->i_sb, tmp_bh.b_blocknr);
493 if (bh) {
494 bh->b_state |= tmp_bh.b_state;
495 return bh;
496 }
497 err = -EIO;
498 }
499 return ERR_PTR(err);
500 }
501
502 static inline struct buffer_head *
503 affs_getemptyblk_ino(struct inode *inode, int block)
504 {
505 struct buffer_head *bh, tmp_bh;
506 int err;
507
508 tmp_bh.b_state = 0;
509 err = affs_get_block(inode, block, &tmp_bh, 1);
510 if (!err) {
511 bh = affs_getemptyblk(inode->i_sb, tmp_bh.b_blocknr);
512 if (bh) {
513 bh->b_state |= tmp_bh.b_state;
514 return bh;
515 }
516 err = -EIO;
517 }
518 return ERR_PTR(err);
519 }
520
521 static int
522 affs_do_readpage_ofs(struct page *page, unsigned to, int create)
523 {
524 struct inode *inode = page->mapping->host;
525 struct super_block *sb = inode->i_sb;
526 struct buffer_head *bh;
527 char *data;
528 unsigned pos = 0;
529 u32 bidx, boff, bsize;
530 u32 tmp;
531
532 pr_debug("%s(%lu, %ld, 0, %d)\n", __func__, inode->i_ino,
533 page->index, to);
534 BUG_ON(to > PAGE_SIZE);
535 bsize = AFFS_SB(sb)->s_data_blksize;
536 tmp = page->index << PAGE_SHIFT;
537 bidx = tmp / bsize;
538 boff = tmp % bsize;
539
540 while (pos < to) {
541 bh = affs_bread_ino(inode, bidx, create);
542 if (IS_ERR(bh))
543 return PTR_ERR(bh);
544 tmp = min(bsize - boff, to - pos);
545 BUG_ON(pos + tmp > to || tmp > bsize);
546 data = kmap_atomic(page);
547 memcpy(data + pos, AFFS_DATA(bh) + boff, tmp);
548 kunmap_atomic(data);
549 affs_brelse(bh);
550 bidx++;
551 pos += tmp;
552 boff = 0;
553 }
554 flush_dcache_page(page);
555 return 0;
556 }
557
558 static int
559 affs_extent_file_ofs(struct inode *inode, u32 newsize)
560 {
561 struct super_block *sb = inode->i_sb;
562 struct buffer_head *bh, *prev_bh;
563 u32 bidx, boff;
564 u32 size, bsize;
565 u32 tmp;
566
567 pr_debug("%s(%lu, %d)\n", __func__, inode->i_ino, newsize);
568 bsize = AFFS_SB(sb)->s_data_blksize;
569 bh = NULL;
570 size = AFFS_I(inode)->mmu_private;
571 bidx = size / bsize;
572 boff = size % bsize;
573 if (boff) {
574 bh = affs_bread_ino(inode, bidx, 0);
575 if (IS_ERR(bh))
576 return PTR_ERR(bh);
577 tmp = min(bsize - boff, newsize - size);
578 BUG_ON(boff + tmp > bsize || tmp > bsize);
579 memset(AFFS_DATA(bh) + boff, 0, tmp);
580 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp);
581 affs_fix_checksum(sb, bh);
582 mark_buffer_dirty_inode(bh, inode);
583 size += tmp;
584 bidx++;
585 } else if (bidx) {
586 bh = affs_bread_ino(inode, bidx - 1, 0);
587 if (IS_ERR(bh))
588 return PTR_ERR(bh);
589 }
590
591 while (size < newsize) {
592 prev_bh = bh;
593 bh = affs_getzeroblk_ino(inode, bidx);
594 if (IS_ERR(bh))
595 goto out;
596 tmp = min(bsize, newsize - size);
597 BUG_ON(tmp > bsize);
598 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
599 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
600 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
601 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
602 affs_fix_checksum(sb, bh);
603 bh->b_state &= ~(1UL << BH_New);
604 mark_buffer_dirty_inode(bh, inode);
605 if (prev_bh) {
606 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
607
608 if (tmp_next)
609 affs_warning(sb, "extent_file_ofs",
610 "next block already set for %d (%d)",
611 bidx, tmp_next);
612 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
613 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
614 mark_buffer_dirty_inode(prev_bh, inode);
615 affs_brelse(prev_bh);
616 }
617 size += bsize;
618 bidx++;
619 }
620 affs_brelse(bh);
621 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
622 return 0;
623
624 out:
625 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
626 return PTR_ERR(bh);
627 }
628
629 static int
630 affs_readpage_ofs(struct file *file, struct page *page)
631 {
632 struct inode *inode = page->mapping->host;
633 u32 to;
634 int err;
635
636 pr_debug("%s(%lu, %ld)\n", __func__, inode->i_ino, page->index);
637 to = PAGE_SIZE;
638 if (((page->index + 1) << PAGE_SHIFT) > inode->i_size) {
639 to = inode->i_size & ~PAGE_MASK;
640 memset(page_address(page) + to, 0, PAGE_SIZE - to);
641 }
642
643 err = affs_do_readpage_ofs(page, to, 0);
644 if (!err)
645 SetPageUptodate(page);
646 unlock_page(page);
647 return err;
648 }
649
650 static int affs_write_begin_ofs(struct file *file, struct address_space *mapping,
651 loff_t pos, unsigned len, unsigned flags,
652 struct page **pagep, void **fsdata)
653 {
654 struct inode *inode = mapping->host;
655 struct page *page;
656 pgoff_t index;
657 int err = 0;
658
659 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos,
660 pos + len);
661 if (pos > AFFS_I(inode)->mmu_private) {
662 /* XXX: this probably leaves a too-big i_size in case of
663 * failure. Should really be updating i_size at write_end time
664 */
665 err = affs_extent_file_ofs(inode, pos);
666 if (err)
667 return err;
668 }
669
670 index = pos >> PAGE_SHIFT;
671 page = grab_cache_page_write_begin(mapping, index, flags);
672 if (!page)
673 return -ENOMEM;
674 *pagep = page;
675
676 if (PageUptodate(page))
677 return 0;
678
679 /* XXX: inefficient but safe in the face of short writes */
680 err = affs_do_readpage_ofs(page, PAGE_SIZE, 1);
681 if (err) {
682 unlock_page(page);
683 put_page(page);
684 }
685 return err;
686 }
687
688 static int affs_write_end_ofs(struct file *file, struct address_space *mapping,
689 loff_t pos, unsigned len, unsigned copied,
690 struct page *page, void *fsdata)
691 {
692 struct inode *inode = mapping->host;
693 struct super_block *sb = inode->i_sb;
694 struct buffer_head *bh, *prev_bh;
695 char *data;
696 u32 bidx, boff, bsize;
697 unsigned from, to;
698 u32 tmp;
699 int written;
700
701 from = pos & (PAGE_SIZE - 1);
702 to = from + len;
703 /*
704 * XXX: not sure if this can handle short copies (len < copied), but
705 * we don't have to, because the page should always be uptodate here,
706 * due to write_begin.
707 */
708
709 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos,
710 pos + len);
711 bsize = AFFS_SB(sb)->s_data_blksize;
712 data = page_address(page);
713
714 bh = NULL;
715 written = 0;
716 tmp = (page->index << PAGE_SHIFT) + from;
717 bidx = tmp / bsize;
718 boff = tmp % bsize;
719 if (boff) {
720 bh = affs_bread_ino(inode, bidx, 0);
721 if (IS_ERR(bh)) {
722 written = PTR_ERR(bh);
723 goto err_first_bh;
724 }
725 tmp = min(bsize - boff, to - from);
726 BUG_ON(boff + tmp > bsize || tmp > bsize);
727 memcpy(AFFS_DATA(bh) + boff, data + from, tmp);
728 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp);
729 affs_fix_checksum(sb, bh);
730 mark_buffer_dirty_inode(bh, inode);
731 written += tmp;
732 from += tmp;
733 bidx++;
734 } else if (bidx) {
735 bh = affs_bread_ino(inode, bidx - 1, 0);
736 if (IS_ERR(bh)) {
737 written = PTR_ERR(bh);
738 goto err_first_bh;
739 }
740 }
741 while (from + bsize <= to) {
742 prev_bh = bh;
743 bh = affs_getemptyblk_ino(inode, bidx);
744 if (IS_ERR(bh))
745 goto err_bh;
746 memcpy(AFFS_DATA(bh), data + from, bsize);
747 if (buffer_new(bh)) {
748 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
749 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
750 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
751 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(bsize);
752 AFFS_DATA_HEAD(bh)->next = 0;
753 bh->b_state &= ~(1UL << BH_New);
754 if (prev_bh) {
755 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
756
757 if (tmp_next)
758 affs_warning(sb, "commit_write_ofs",
759 "next block already set for %d (%d)",
760 bidx, tmp_next);
761 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
762 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
763 mark_buffer_dirty_inode(prev_bh, inode);
764 }
765 }
766 affs_brelse(prev_bh);
767 affs_fix_checksum(sb, bh);
768 mark_buffer_dirty_inode(bh, inode);
769 written += bsize;
770 from += bsize;
771 bidx++;
772 }
773 if (from < to) {
774 prev_bh = bh;
775 bh = affs_bread_ino(inode, bidx, 1);
776 if (IS_ERR(bh))
777 goto err_bh;
778 tmp = min(bsize, to - from);
779 BUG_ON(tmp > bsize);
780 memcpy(AFFS_DATA(bh), data + from, tmp);
781 if (buffer_new(bh)) {
782 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
783 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
784 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
785 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
786 AFFS_DATA_HEAD(bh)->next = 0;
787 bh->b_state &= ~(1UL << BH_New);
788 if (prev_bh) {
789 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
790
791 if (tmp_next)
792 affs_warning(sb, "commit_write_ofs",
793 "next block already set for %d (%d)",
794 bidx, tmp_next);
795 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
796 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
797 mark_buffer_dirty_inode(prev_bh, inode);
798 }
799 } else if (be32_to_cpu(AFFS_DATA_HEAD(bh)->size) < tmp)
800 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
801 affs_brelse(prev_bh);
802 affs_fix_checksum(sb, bh);
803 mark_buffer_dirty_inode(bh, inode);
804 written += tmp;
805 from += tmp;
806 bidx++;
807 }
808 SetPageUptodate(page);
809
810 done:
811 affs_brelse(bh);
812 tmp = (page->index << PAGE_SHIFT) + from;
813 if (tmp > inode->i_size)
814 inode->i_size = AFFS_I(inode)->mmu_private = tmp;
815
816 /* Clear Archived bit on file writes, as AmigaOS would do */
817 if (AFFS_I(inode)->i_protect & FIBF_ARCHIVED) {
818 AFFS_I(inode)->i_protect &= ~FIBF_ARCHIVED;
819 mark_inode_dirty(inode);
820 }
821
822 err_first_bh:
823 unlock_page(page);
824 put_page(page);
825
826 return written;
827
828 err_bh:
829 bh = prev_bh;
830 if (!written)
831 written = PTR_ERR(bh);
832 goto done;
833 }
834
835 const struct address_space_operations affs_aops_ofs = {
836 .readpage = affs_readpage_ofs,
837 //.writepage = affs_writepage_ofs,
838 .write_begin = affs_write_begin_ofs,
839 .write_end = affs_write_end_ofs
840 };
841
842 /* Free any preallocated blocks. */
843
844 void
845 affs_free_prealloc(struct inode *inode)
846 {
847 struct super_block *sb = inode->i_sb;
848
849 pr_debug("free_prealloc(ino=%lu)\n", inode->i_ino);
850
851 while (AFFS_I(inode)->i_pa_cnt) {
852 AFFS_I(inode)->i_pa_cnt--;
853 affs_free_block(sb, ++AFFS_I(inode)->i_lastalloc);
854 }
855 }
856
857 /* Truncate (or enlarge) a file to the requested size. */
858
859 void
860 affs_truncate(struct inode *inode)
861 {
862 struct super_block *sb = inode->i_sb;
863 u32 ext, ext_key;
864 u32 last_blk, blkcnt, blk;
865 u32 size;
866 struct buffer_head *ext_bh;
867 int i;
868
869 pr_debug("truncate(inode=%lu, oldsize=%llu, newsize=%llu)\n",
870 inode->i_ino, AFFS_I(inode)->mmu_private, inode->i_size);
871
872 last_blk = 0;
873 ext = 0;
874 if (inode->i_size) {
875 last_blk = ((u32)inode->i_size - 1) / AFFS_SB(sb)->s_data_blksize;
876 ext = last_blk / AFFS_SB(sb)->s_hashsize;
877 }
878
879 if (inode->i_size > AFFS_I(inode)->mmu_private) {
880 struct address_space *mapping = inode->i_mapping;
881 struct page *page;
882 void *fsdata;
883 loff_t isize = inode->i_size;
884 int res;
885
886 res = mapping->a_ops->write_begin(NULL, mapping, isize, 0, 0, &page, &fsdata);
887 if (!res)
888 res = mapping->a_ops->write_end(NULL, mapping, isize, 0, 0, page, fsdata);
889 else
890 inode->i_size = AFFS_I(inode)->mmu_private;
891 mark_inode_dirty(inode);
892 return;
893 } else if (inode->i_size == AFFS_I(inode)->mmu_private)
894 return;
895
896 // lock cache
897 ext_bh = affs_get_extblock(inode, ext);
898 if (IS_ERR(ext_bh)) {
899 affs_warning(sb, "truncate",
900 "unexpected read error for ext block %u (%ld)",
901 ext, PTR_ERR(ext_bh));
902 return;
903 }
904 if (AFFS_I(inode)->i_lc) {
905 /* clear linear cache */
906 i = (ext + 1) >> AFFS_I(inode)->i_lc_shift;
907 if (AFFS_I(inode)->i_lc_size > i) {
908 AFFS_I(inode)->i_lc_size = i;
909 for (; i < AFFS_LC_SIZE; i++)
910 AFFS_I(inode)->i_lc[i] = 0;
911 }
912 /* clear associative cache */
913 for (i = 0; i < AFFS_AC_SIZE; i++)
914 if (AFFS_I(inode)->i_ac[i].ext >= ext)
915 AFFS_I(inode)->i_ac[i].ext = 0;
916 }
917 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
918
919 blkcnt = AFFS_I(inode)->i_blkcnt;
920 i = 0;
921 blk = last_blk;
922 if (inode->i_size) {
923 i = last_blk % AFFS_SB(sb)->s_hashsize + 1;
924 blk++;
925 } else
926 AFFS_HEAD(ext_bh)->first_data = 0;
927 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(i);
928 size = AFFS_SB(sb)->s_hashsize;
929 if (size > blkcnt - blk + i)
930 size = blkcnt - blk + i;
931 for (; i < size; i++, blk++) {
932 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
933 AFFS_BLOCK(sb, ext_bh, i) = 0;
934 }
935 AFFS_TAIL(sb, ext_bh)->extension = 0;
936 affs_fix_checksum(sb, ext_bh);
937 mark_buffer_dirty_inode(ext_bh, inode);
938 affs_brelse(ext_bh);
939
940 if (inode->i_size) {
941 AFFS_I(inode)->i_blkcnt = last_blk + 1;
942 AFFS_I(inode)->i_extcnt = ext + 1;
943 if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_OFS)) {
944 struct buffer_head *bh = affs_bread_ino(inode, last_blk, 0);
945 u32 tmp;
946 if (IS_ERR(bh)) {
947 affs_warning(sb, "truncate",
948 "unexpected read error for last block %u (%ld)",
949 ext, PTR_ERR(bh));
950 return;
951 }
952 tmp = be32_to_cpu(AFFS_DATA_HEAD(bh)->next);
953 AFFS_DATA_HEAD(bh)->next = 0;
954 affs_adjust_checksum(bh, -tmp);
955 affs_brelse(bh);
956 }
957 } else {
958 AFFS_I(inode)->i_blkcnt = 0;
959 AFFS_I(inode)->i_extcnt = 1;
960 }
961 AFFS_I(inode)->mmu_private = inode->i_size;
962 // unlock cache
963
964 while (ext_key) {
965 ext_bh = affs_bread(sb, ext_key);
966 size = AFFS_SB(sb)->s_hashsize;
967 if (size > blkcnt - blk)
968 size = blkcnt - blk;
969 for (i = 0; i < size; i++, blk++)
970 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
971 affs_free_block(sb, ext_key);
972 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
973 affs_brelse(ext_bh);
974 }
975 affs_free_prealloc(inode);
976 }
977
978 int affs_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
979 {
980 struct inode *inode = filp->f_mapping->host;
981 int ret, err;
982
983 err = file_write_and_wait_range(filp, start, end);
984 if (err)
985 return err;
986
987 inode_lock(inode);
988 ret = write_inode_now(inode, 0);
989 err = sync_blockdev(inode->i_sb->s_bdev);
990 if (!ret)
991 ret = err;
992 inode_unlock(inode);
993 return ret;
994 }
995 const struct file_operations affs_file_operations = {
996 .llseek = generic_file_llseek,
997 .read_iter = generic_file_read_iter,
998 .write_iter = generic_file_write_iter,
999 .mmap = generic_file_mmap,
1000 .open = affs_file_open,
1001 .release = affs_file_release,
1002 .fsync = affs_file_fsync,
1003 .splice_read = generic_file_splice_read,
1004 };
1005
1006 const struct inode_operations affs_file_inode_operations = {
1007 .setattr = affs_notify_change,
1008 };
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