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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
21static int affs_grow_extcache(struct inode *inode, u32 lc_idx);
22static struct buffer_head *affs_alloc_extblock(struct inode *inode, struct buffer_head *bh, u32 ext);
23static inline struct buffer_head *affs_get_extblock(struct inode *inode, u32 ext);
24static struct buffer_head *affs_get_extblock_slow(struct inode *inode, u32 ext);
25static int affs_file_open(struct inode *inode, struct file *filp);
26static int affs_file_release(struct inode *inode, struct file *filp);
27
28const struct file_operations affs_file_operations = {
29 .llseek = generic_file_llseek,
30 .read = do_sync_read,
31 .aio_read = generic_file_aio_read,
32 .write = do_sync_write,
33 .aio_write = generic_file_aio_write,
34 .mmap = generic_file_mmap,
35 .open = affs_file_open,
36 .release = affs_file_release,
37 .fsync = affs_file_fsync,
38 .splice_read = generic_file_splice_read,
39};
40
41const struct inode_operations affs_file_inode_operations = {
42 .truncate = affs_truncate,
43 .setattr = affs_notify_change,
44};
45
46static int
47affs_file_open(struct inode *inode, struct file *filp)
48{
49 pr_debug("AFFS: open(%lu,%d)\n",
50 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
51 atomic_inc(&AFFS_I(inode)->i_opencnt);
52 return 0;
53}
54
55static int
56affs_file_release(struct inode *inode, struct file *filp)
57{
58 pr_debug("AFFS: release(%lu, %d)\n",
59 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
60
61 if (atomic_dec_and_test(&AFFS_I(inode)->i_opencnt)) {
62 mutex_lock(&inode->i_mutex);
63 if (inode->i_size != AFFS_I(inode)->mmu_private)
64 affs_truncate(inode);
65 affs_free_prealloc(inode);
66 mutex_unlock(&inode->i_mutex);
67 }
68
69 return 0;
70}
71
72static int
73affs_grow_extcache(struct inode *inode, u32 lc_idx)
74{
75 struct super_block *sb = inode->i_sb;
76 struct buffer_head *bh;
77 u32 lc_max;
78 int i, j, key;
79
80 if (!AFFS_I(inode)->i_lc) {
81 char *ptr = (char *)get_zeroed_page(GFP_NOFS);
82 if (!ptr)
83 return -ENOMEM;
84 AFFS_I(inode)->i_lc = (u32 *)ptr;
85 AFFS_I(inode)->i_ac = (struct affs_ext_key *)(ptr + AFFS_CACHE_SIZE / 2);
86 }
87
88 lc_max = AFFS_LC_SIZE << AFFS_I(inode)->i_lc_shift;
89
90 if (AFFS_I(inode)->i_extcnt > lc_max) {
91 u32 lc_shift, lc_mask, tmp, off;
92
93 /* need to recalculate linear cache, start from old size */
94 lc_shift = AFFS_I(inode)->i_lc_shift;
95 tmp = (AFFS_I(inode)->i_extcnt / AFFS_LC_SIZE) >> lc_shift;
96 for (; tmp; tmp >>= 1)
97 lc_shift++;
98 lc_mask = (1 << lc_shift) - 1;
99
100 /* fix idx and old size to new shift */
101 lc_idx >>= (lc_shift - AFFS_I(inode)->i_lc_shift);
102 AFFS_I(inode)->i_lc_size >>= (lc_shift - AFFS_I(inode)->i_lc_shift);
103
104 /* first shrink old cache to make more space */
105 off = 1 << (lc_shift - AFFS_I(inode)->i_lc_shift);
106 for (i = 1, j = off; j < AFFS_LC_SIZE; i++, j += off)
107 AFFS_I(inode)->i_ac[i] = AFFS_I(inode)->i_ac[j];
108
109 AFFS_I(inode)->i_lc_shift = lc_shift;
110 AFFS_I(inode)->i_lc_mask = lc_mask;
111 }
112
113 /* fill cache to the needed index */
114 i = AFFS_I(inode)->i_lc_size;
115 AFFS_I(inode)->i_lc_size = lc_idx + 1;
116 for (; i <= lc_idx; i++) {
117 if (!i) {
118 AFFS_I(inode)->i_lc[0] = inode->i_ino;
119 continue;
120 }
121 key = AFFS_I(inode)->i_lc[i - 1];
122 j = AFFS_I(inode)->i_lc_mask + 1;
123 // unlock cache
124 for (; j > 0; j--) {
125 bh = affs_bread(sb, key);
126 if (!bh)
127 goto err;
128 key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
129 affs_brelse(bh);
130 }
131 // lock cache
132 AFFS_I(inode)->i_lc[i] = key;
133 }
134
135 return 0;
136
137err:
138 // lock cache
139 return -EIO;
140}
141
142static struct buffer_head *
143affs_alloc_extblock(struct inode *inode, struct buffer_head *bh, u32 ext)
144{
145 struct super_block *sb = inode->i_sb;
146 struct buffer_head *new_bh;
147 u32 blocknr, tmp;
148
149 blocknr = affs_alloc_block(inode, bh->b_blocknr);
150 if (!blocknr)
151 return ERR_PTR(-ENOSPC);
152
153 new_bh = affs_getzeroblk(sb, blocknr);
154 if (!new_bh) {
155 affs_free_block(sb, blocknr);
156 return ERR_PTR(-EIO);
157 }
158
159 AFFS_HEAD(new_bh)->ptype = cpu_to_be32(T_LIST);
160 AFFS_HEAD(new_bh)->key = cpu_to_be32(blocknr);
161 AFFS_TAIL(sb, new_bh)->stype = cpu_to_be32(ST_FILE);
162 AFFS_TAIL(sb, new_bh)->parent = cpu_to_be32(inode->i_ino);
163 affs_fix_checksum(sb, new_bh);
164
165 mark_buffer_dirty_inode(new_bh, inode);
166
167 tmp = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
168 if (tmp)
169 affs_warning(sb, "alloc_ext", "previous extension set (%x)", tmp);
170 AFFS_TAIL(sb, bh)->extension = cpu_to_be32(blocknr);
171 affs_adjust_checksum(bh, blocknr - tmp);
172 mark_buffer_dirty_inode(bh, inode);
173
174 AFFS_I(inode)->i_extcnt++;
175 mark_inode_dirty(inode);
176
177 return new_bh;
178}
179
180static inline struct buffer_head *
181affs_get_extblock(struct inode *inode, u32 ext)
182{
183 /* inline the simplest case: same extended block as last time */
184 struct buffer_head *bh = AFFS_I(inode)->i_ext_bh;
185 if (ext == AFFS_I(inode)->i_ext_last)
186 get_bh(bh);
187 else
188 /* we have to do more (not inlined) */
189 bh = affs_get_extblock_slow(inode, ext);
190
191 return bh;
192}
193
194static struct buffer_head *
195affs_get_extblock_slow(struct inode *inode, u32 ext)
196{
197 struct super_block *sb = inode->i_sb;
198 struct buffer_head *bh;
199 u32 ext_key;
200 u32 lc_idx, lc_off, ac_idx;
201 u32 tmp, idx;
202
203 if (ext == AFFS_I(inode)->i_ext_last + 1) {
204 /* read the next extended block from the current one */
205 bh = AFFS_I(inode)->i_ext_bh;
206 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
207 if (ext < AFFS_I(inode)->i_extcnt)
208 goto read_ext;
209 if (ext > AFFS_I(inode)->i_extcnt)
210 BUG();
211 bh = affs_alloc_extblock(inode, bh, ext);
212 if (IS_ERR(bh))
213 return bh;
214 goto store_ext;
215 }
216
217 if (ext == 0) {
218 /* we seek back to the file header block */
219 ext_key = inode->i_ino;
220 goto read_ext;
221 }
222
223 if (ext >= AFFS_I(inode)->i_extcnt) {
224 struct buffer_head *prev_bh;
225
226 /* allocate a new extended block */
227 if (ext > AFFS_I(inode)->i_extcnt)
228 BUG();
229
230 /* get previous extended block */
231 prev_bh = affs_get_extblock(inode, ext - 1);
232 if (IS_ERR(prev_bh))
233 return prev_bh;
234 bh = affs_alloc_extblock(inode, prev_bh, ext);
235 affs_brelse(prev_bh);
236 if (IS_ERR(bh))
237 return bh;
238 goto store_ext;
239 }
240
241again:
242 /* check if there is an extended cache and whether it's large enough */
243 lc_idx = ext >> AFFS_I(inode)->i_lc_shift;
244 lc_off = ext & AFFS_I(inode)->i_lc_mask;
245
246 if (lc_idx >= AFFS_I(inode)->i_lc_size) {
247 int err;
248
249 err = affs_grow_extcache(inode, lc_idx);
250 if (err)
251 return ERR_PTR(err);
252 goto again;
253 }
254
255 /* every n'th key we find in the linear cache */
256 if (!lc_off) {
257 ext_key = AFFS_I(inode)->i_lc[lc_idx];
258 goto read_ext;
259 }
260
261 /* maybe it's still in the associative cache */
262 ac_idx = (ext - lc_idx - 1) & AFFS_AC_MASK;
263 if (AFFS_I(inode)->i_ac[ac_idx].ext == ext) {
264 ext_key = AFFS_I(inode)->i_ac[ac_idx].key;
265 goto read_ext;
266 }
267
268 /* try to find one of the previous extended blocks */
269 tmp = ext;
270 idx = ac_idx;
271 while (--tmp, --lc_off > 0) {
272 idx = (idx - 1) & AFFS_AC_MASK;
273 if (AFFS_I(inode)->i_ac[idx].ext == tmp) {
274 ext_key = AFFS_I(inode)->i_ac[idx].key;
275 goto find_ext;
276 }
277 }
278
279 /* fall back to the linear cache */
280 ext_key = AFFS_I(inode)->i_lc[lc_idx];
281find_ext:
282 /* read all extended blocks until we find the one we need */
283 //unlock cache
284 do {
285 bh = affs_bread(sb, ext_key);
286 if (!bh)
287 goto err_bread;
288 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
289 affs_brelse(bh);
290 tmp++;
291 } while (tmp < ext);
292 //lock cache
293
294 /* store it in the associative cache */
295 // recalculate ac_idx?
296 AFFS_I(inode)->i_ac[ac_idx].ext = ext;
297 AFFS_I(inode)->i_ac[ac_idx].key = ext_key;
298
299read_ext:
300 /* finally read the right extended block */
301 //unlock cache
302 bh = affs_bread(sb, ext_key);
303 if (!bh)
304 goto err_bread;
305 //lock cache
306
307store_ext:
308 /* release old cached extended block and store the new one */
309 affs_brelse(AFFS_I(inode)->i_ext_bh);
310 AFFS_I(inode)->i_ext_last = ext;
311 AFFS_I(inode)->i_ext_bh = bh;
312 get_bh(bh);
313
314 return bh;
315
316err_bread:
317 affs_brelse(bh);
318 return ERR_PTR(-EIO);
319}
320
321static int
322affs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh_result, int create)
323{
324 struct super_block *sb = inode->i_sb;
325 struct buffer_head *ext_bh;
326 u32 ext;
327
328 pr_debug("AFFS: get_block(%u, %lu)\n", (u32)inode->i_ino, (unsigned long)block);
329
330 BUG_ON(block > (sector_t)0x7fffffffUL);
331
332 if (block >= AFFS_I(inode)->i_blkcnt) {
333 if (block > AFFS_I(inode)->i_blkcnt || !create)
334 goto err_big;
335 } else
336 create = 0;
337
338 //lock cache
339 affs_lock_ext(inode);
340
341 ext = (u32)block / AFFS_SB(sb)->s_hashsize;
342 block -= ext * AFFS_SB(sb)->s_hashsize;
343 ext_bh = affs_get_extblock(inode, ext);
344 if (IS_ERR(ext_bh))
345 goto err_ext;
346 map_bh(bh_result, sb, (sector_t)be32_to_cpu(AFFS_BLOCK(sb, ext_bh, block)));
347
348 if (create) {
349 u32 blocknr = affs_alloc_block(inode, ext_bh->b_blocknr);
350 if (!blocknr)
351 goto err_alloc;
352 set_buffer_new(bh_result);
353 AFFS_I(inode)->mmu_private += AFFS_SB(sb)->s_data_blksize;
354 AFFS_I(inode)->i_blkcnt++;
355
356 /* store new block */
357 if (bh_result->b_blocknr)
358 affs_warning(sb, "get_block", "block already set (%x)", bh_result->b_blocknr);
359 AFFS_BLOCK(sb, ext_bh, block) = cpu_to_be32(blocknr);
360 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(block + 1);
361 affs_adjust_checksum(ext_bh, blocknr - bh_result->b_blocknr + 1);
362 bh_result->b_blocknr = blocknr;
363
364 if (!block) {
365 /* insert first block into header block */
366 u32 tmp = be32_to_cpu(AFFS_HEAD(ext_bh)->first_data);
367 if (tmp)
368 affs_warning(sb, "get_block", "first block already set (%d)", tmp);
369 AFFS_HEAD(ext_bh)->first_data = cpu_to_be32(blocknr);
370 affs_adjust_checksum(ext_bh, blocknr - tmp);
371 }
372 }
373
374 affs_brelse(ext_bh);
375 //unlock cache
376 affs_unlock_ext(inode);
377 return 0;
378
379err_big:
380 affs_error(inode->i_sb,"get_block","strange block request %d", block);
381 return -EIO;
382err_ext:
383 // unlock cache
384 affs_unlock_ext(inode);
385 return PTR_ERR(ext_bh);
386err_alloc:
387 brelse(ext_bh);
388 clear_buffer_mapped(bh_result);
389 bh_result->b_bdev = NULL;
390 // unlock cache
391 affs_unlock_ext(inode);
392 return -ENOSPC;
393}
394
395static int affs_writepage(struct page *page, struct writeback_control *wbc)
396{
397 return block_write_full_page(page, affs_get_block, wbc);
398}
399
400static int affs_readpage(struct file *file, struct page *page)
401{
402 return block_read_full_page(page, affs_get_block);
403}
404
405static int affs_write_begin(struct file *file, struct address_space *mapping,
406 loff_t pos, unsigned len, unsigned flags,
407 struct page **pagep, void **fsdata)
408{
409 int ret;
410
411 *pagep = NULL;
412 ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
413 affs_get_block,
414 &AFFS_I(mapping->host)->mmu_private);
415 if (unlikely(ret)) {
416 loff_t isize = mapping->host->i_size;
417 if (pos + len > isize)
418 vmtruncate(mapping->host, isize);
419 }
420
421 return ret;
422}
423
424static sector_t _affs_bmap(struct address_space *mapping, sector_t block)
425{
426 return generic_block_bmap(mapping,block,affs_get_block);
427}
428
429const struct address_space_operations affs_aops = {
430 .readpage = affs_readpage,
431 .writepage = affs_writepage,
432 .write_begin = affs_write_begin,
433 .write_end = generic_write_end,
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
494static int
495affs_do_readpage_ofs(struct file *file, struct page *page, unsigned from, unsigned to)
496{
497 struct inode *inode = page->mapping->host;
498 struct super_block *sb = inode->i_sb;
499 struct buffer_head *bh;
500 char *data;
501 u32 bidx, boff, bsize;
502 u32 tmp;
503
504 pr_debug("AFFS: read_page(%u, %ld, %d, %d)\n", (u32)inode->i_ino, page->index, from, to);
505 BUG_ON(from > to || to > PAGE_CACHE_SIZE);
506 kmap(page);
507 data = page_address(page);
508 bsize = AFFS_SB(sb)->s_data_blksize;
509 tmp = (page->index << PAGE_CACHE_SHIFT) + from;
510 bidx = tmp / bsize;
511 boff = tmp % bsize;
512
513 while (from < to) {
514 bh = affs_bread_ino(inode, bidx, 0);
515 if (IS_ERR(bh))
516 return PTR_ERR(bh);
517 tmp = min(bsize - boff, to - from);
518 BUG_ON(from + tmp > to || tmp > bsize);
519 memcpy(data + from, AFFS_DATA(bh) + boff, tmp);
520 affs_brelse(bh);
521 bidx++;
522 from += tmp;
523 boff = 0;
524 }
525 flush_dcache_page(page);
526 kunmap(page);
527 return 0;
528}
529
530static int
531affs_extent_file_ofs(struct inode *inode, u32 newsize)
532{
533 struct super_block *sb = inode->i_sb;
534 struct buffer_head *bh, *prev_bh;
535 u32 bidx, boff;
536 u32 size, bsize;
537 u32 tmp;
538
539 pr_debug("AFFS: extent_file(%u, %d)\n", (u32)inode->i_ino, newsize);
540 bsize = AFFS_SB(sb)->s_data_blksize;
541 bh = NULL;
542 size = AFFS_I(inode)->mmu_private;
543 bidx = size / bsize;
544 boff = size % bsize;
545 if (boff) {
546 bh = affs_bread_ino(inode, bidx, 0);
547 if (IS_ERR(bh))
548 return PTR_ERR(bh);
549 tmp = min(bsize - boff, newsize - size);
550 BUG_ON(boff + tmp > bsize || tmp > bsize);
551 memset(AFFS_DATA(bh) + boff, 0, tmp);
552 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp);
553 affs_fix_checksum(sb, bh);
554 mark_buffer_dirty_inode(bh, inode);
555 size += tmp;
556 bidx++;
557 } else if (bidx) {
558 bh = affs_bread_ino(inode, bidx - 1, 0);
559 if (IS_ERR(bh))
560 return PTR_ERR(bh);
561 }
562
563 while (size < newsize) {
564 prev_bh = bh;
565 bh = affs_getzeroblk_ino(inode, bidx);
566 if (IS_ERR(bh))
567 goto out;
568 tmp = min(bsize, newsize - size);
569 BUG_ON(tmp > bsize);
570 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
571 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
572 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
573 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
574 affs_fix_checksum(sb, bh);
575 bh->b_state &= ~(1UL << BH_New);
576 mark_buffer_dirty_inode(bh, inode);
577 if (prev_bh) {
578 u32 tmp = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
579 if (tmp)
580 affs_warning(sb, "extent_file_ofs", "next block already set for %d (%d)", bidx, tmp);
581 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
582 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp);
583 mark_buffer_dirty_inode(prev_bh, inode);
584 affs_brelse(prev_bh);
585 }
586 size += bsize;
587 bidx++;
588 }
589 affs_brelse(bh);
590 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
591 return 0;
592
593out:
594 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
595 return PTR_ERR(bh);
596}
597
598static int
599affs_readpage_ofs(struct file *file, struct page *page)
600{
601 struct inode *inode = page->mapping->host;
602 u32 to;
603 int err;
604
605 pr_debug("AFFS: read_page(%u, %ld)\n", (u32)inode->i_ino, page->index);
606 to = PAGE_CACHE_SIZE;
607 if (((page->index + 1) << PAGE_CACHE_SHIFT) > inode->i_size) {
608 to = inode->i_size & ~PAGE_CACHE_MASK;
609 memset(page_address(page) + to, 0, PAGE_CACHE_SIZE - to);
610 }
611
612 err = affs_do_readpage_ofs(file, page, 0, to);
613 if (!err)
614 SetPageUptodate(page);
615 unlock_page(page);
616 return err;
617}
618
619static int affs_write_begin_ofs(struct file *file, struct address_space *mapping,
620 loff_t pos, unsigned len, unsigned flags,
621 struct page **pagep, void **fsdata)
622{
623 struct inode *inode = mapping->host;
624 struct page *page;
625 pgoff_t index;
626 int err = 0;
627
628 pr_debug("AFFS: write_begin(%u, %llu, %llu)\n", (u32)inode->i_ino, (unsigned long long)pos, (unsigned long long)pos + len);
629 if (pos > AFFS_I(inode)->mmu_private) {
630 /* XXX: this probably leaves a too-big i_size in case of
631 * failure. Should really be updating i_size at write_end time
632 */
633 err = affs_extent_file_ofs(inode, pos);
634 if (err)
635 return err;
636 }
637
638 index = pos >> PAGE_CACHE_SHIFT;
639 page = grab_cache_page_write_begin(mapping, index, flags);
640 if (!page)
641 return -ENOMEM;
642 *pagep = page;
643
644 if (PageUptodate(page))
645 return 0;
646
647 /* XXX: inefficient but safe in the face of short writes */
648 err = affs_do_readpage_ofs(file, page, 0, PAGE_CACHE_SIZE);
649 if (err) {
650 unlock_page(page);
651 page_cache_release(page);
652 }
653 return err;
654}
655
656static int affs_write_end_ofs(struct file *file, struct address_space *mapping,
657 loff_t pos, unsigned len, unsigned copied,
658 struct page *page, void *fsdata)
659{
660 struct inode *inode = mapping->host;
661 struct super_block *sb = inode->i_sb;
662 struct buffer_head *bh, *prev_bh;
663 char *data;
664 u32 bidx, boff, bsize;
665 unsigned from, to;
666 u32 tmp;
667 int written;
668
669 from = pos & (PAGE_CACHE_SIZE - 1);
670 to = pos + len;
671 /*
672 * XXX: not sure if this can handle short copies (len < copied), but
673 * we don't have to, because the page should always be uptodate here,
674 * due to write_begin.
675 */
676
677 pr_debug("AFFS: write_begin(%u, %llu, %llu)\n", (u32)inode->i_ino, (unsigned long long)pos, (unsigned long long)pos + len);
678 bsize = AFFS_SB(sb)->s_data_blksize;
679 data = page_address(page);
680
681 bh = NULL;
682 written = 0;
683 tmp = (page->index << PAGE_CACHE_SHIFT) + from;
684 bidx = tmp / bsize;
685 boff = tmp % bsize;
686 if (boff) {
687 bh = affs_bread_ino(inode, bidx, 0);
688 if (IS_ERR(bh))
689 return PTR_ERR(bh);
690 tmp = min(bsize - boff, to - from);
691 BUG_ON(boff + tmp > bsize || tmp > bsize);
692 memcpy(AFFS_DATA(bh) + boff, data + from, tmp);
693 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp);
694 affs_fix_checksum(sb, bh);
695 mark_buffer_dirty_inode(bh, inode);
696 written += tmp;
697 from += tmp;
698 bidx++;
699 } else if (bidx) {
700 bh = affs_bread_ino(inode, bidx - 1, 0);
701 if (IS_ERR(bh))
702 return PTR_ERR(bh);
703 }
704 while (from + bsize <= to) {
705 prev_bh = bh;
706 bh = affs_getemptyblk_ino(inode, bidx);
707 if (IS_ERR(bh))
708 goto out;
709 memcpy(AFFS_DATA(bh), data + from, bsize);
710 if (buffer_new(bh)) {
711 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
712 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
713 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
714 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(bsize);
715 AFFS_DATA_HEAD(bh)->next = 0;
716 bh->b_state &= ~(1UL << BH_New);
717 if (prev_bh) {
718 u32 tmp = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
719 if (tmp)
720 affs_warning(sb, "commit_write_ofs", "next block already set for %d (%d)", bidx, tmp);
721 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
722 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp);
723 mark_buffer_dirty_inode(prev_bh, inode);
724 }
725 }
726 affs_brelse(prev_bh);
727 affs_fix_checksum(sb, bh);
728 mark_buffer_dirty_inode(bh, inode);
729 written += bsize;
730 from += bsize;
731 bidx++;
732 }
733 if (from < to) {
734 prev_bh = bh;
735 bh = affs_bread_ino(inode, bidx, 1);
736 if (IS_ERR(bh))
737 goto out;
738 tmp = min(bsize, to - from);
739 BUG_ON(tmp > bsize);
740 memcpy(AFFS_DATA(bh), data + from, tmp);
741 if (buffer_new(bh)) {
742 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
743 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
744 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
745 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
746 AFFS_DATA_HEAD(bh)->next = 0;
747 bh->b_state &= ~(1UL << BH_New);
748 if (prev_bh) {
749 u32 tmp = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
750 if (tmp)
751 affs_warning(sb, "commit_write_ofs", "next block already set for %d (%d)", bidx, tmp);
752 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
753 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp);
754 mark_buffer_dirty_inode(prev_bh, inode);
755 }
756 } else if (be32_to_cpu(AFFS_DATA_HEAD(bh)->size) < tmp)
757 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
758 affs_brelse(prev_bh);
759 affs_fix_checksum(sb, bh);
760 mark_buffer_dirty_inode(bh, inode);
761 written += tmp;
762 from += tmp;
763 bidx++;
764 }
765 SetPageUptodate(page);
766
767done:
768 affs_brelse(bh);
769 tmp = (page->index << PAGE_CACHE_SHIFT) + from;
770 if (tmp > inode->i_size)
771 inode->i_size = AFFS_I(inode)->mmu_private = tmp;
772
773 unlock_page(page);
774 page_cache_release(page);
775
776 return written;
777
778out:
779 bh = prev_bh;
780 if (!written)
781 written = PTR_ERR(bh);
782 goto done;
783}
784
785const struct address_space_operations affs_aops_ofs = {
786 .readpage = affs_readpage_ofs,
787 //.writepage = affs_writepage_ofs,
788 .write_begin = affs_write_begin_ofs,
789 .write_end = affs_write_end_ofs
790};
791
792/* Free any preallocated blocks. */
793
794void
795affs_free_prealloc(struct inode *inode)
796{
797 struct super_block *sb = inode->i_sb;
798
799 pr_debug("AFFS: free_prealloc(ino=%lu)\n", inode->i_ino);
800
801 while (AFFS_I(inode)->i_pa_cnt) {
802 AFFS_I(inode)->i_pa_cnt--;
803 affs_free_block(sb, ++AFFS_I(inode)->i_lastalloc);
804 }
805}
806
807/* Truncate (or enlarge) a file to the requested size. */
808
809void
810affs_truncate(struct inode *inode)
811{
812 struct super_block *sb = inode->i_sb;
813 u32 ext, ext_key;
814 u32 last_blk, blkcnt, blk;
815 u32 size;
816 struct buffer_head *ext_bh;
817 int i;
818
819 pr_debug("AFFS: truncate(inode=%d, oldsize=%u, newsize=%u)\n",
820 (u32)inode->i_ino, (u32)AFFS_I(inode)->mmu_private, (u32)inode->i_size);
821
822 last_blk = 0;
823 ext = 0;
824 if (inode->i_size) {
825 last_blk = ((u32)inode->i_size - 1) / AFFS_SB(sb)->s_data_blksize;
826 ext = last_blk / AFFS_SB(sb)->s_hashsize;
827 }
828
829 if (inode->i_size > AFFS_I(inode)->mmu_private) {
830 struct address_space *mapping = inode->i_mapping;
831 struct page *page;
832 void *fsdata;
833 u32 size = inode->i_size;
834 int res;
835
836 res = mapping->a_ops->write_begin(NULL, mapping, size, 0, 0, &page, &fsdata);
837 if (!res)
838 res = mapping->a_ops->write_end(NULL, mapping, size, 0, 0, page, fsdata);
839 else
840 inode->i_size = AFFS_I(inode)->mmu_private;
841 mark_inode_dirty(inode);
842 return;
843 } else if (inode->i_size == AFFS_I(inode)->mmu_private)
844 return;
845
846 // lock cache
847 ext_bh = affs_get_extblock(inode, ext);
848 if (IS_ERR(ext_bh)) {
849 affs_warning(sb, "truncate", "unexpected read error for ext block %u (%d)",
850 ext, PTR_ERR(ext_bh));
851 return;
852 }
853 if (AFFS_I(inode)->i_lc) {
854 /* clear linear cache */
855 i = (ext + 1) >> AFFS_I(inode)->i_lc_shift;
856 if (AFFS_I(inode)->i_lc_size > i) {
857 AFFS_I(inode)->i_lc_size = i;
858 for (; i < AFFS_LC_SIZE; i++)
859 AFFS_I(inode)->i_lc[i] = 0;
860 }
861 /* clear associative cache */
862 for (i = 0; i < AFFS_AC_SIZE; i++)
863 if (AFFS_I(inode)->i_ac[i].ext >= ext)
864 AFFS_I(inode)->i_ac[i].ext = 0;
865 }
866 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
867
868 blkcnt = AFFS_I(inode)->i_blkcnt;
869 i = 0;
870 blk = last_blk;
871 if (inode->i_size) {
872 i = last_blk % AFFS_SB(sb)->s_hashsize + 1;
873 blk++;
874 } else
875 AFFS_HEAD(ext_bh)->first_data = 0;
876 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(i);
877 size = AFFS_SB(sb)->s_hashsize;
878 if (size > blkcnt - blk + i)
879 size = blkcnt - blk + i;
880 for (; i < size; i++, blk++) {
881 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
882 AFFS_BLOCK(sb, ext_bh, i) = 0;
883 }
884 AFFS_TAIL(sb, ext_bh)->extension = 0;
885 affs_fix_checksum(sb, ext_bh);
886 mark_buffer_dirty_inode(ext_bh, inode);
887 affs_brelse(ext_bh);
888
889 if (inode->i_size) {
890 AFFS_I(inode)->i_blkcnt = last_blk + 1;
891 AFFS_I(inode)->i_extcnt = ext + 1;
892 if (AFFS_SB(sb)->s_flags & SF_OFS) {
893 struct buffer_head *bh = affs_bread_ino(inode, last_blk, 0);
894 u32 tmp;
895 if (IS_ERR(bh)) {
896 affs_warning(sb, "truncate", "unexpected read error for last block %u (%d)",
897 ext, PTR_ERR(bh));
898 return;
899 }
900 tmp = be32_to_cpu(AFFS_DATA_HEAD(bh)->next);
901 AFFS_DATA_HEAD(bh)->next = 0;
902 affs_adjust_checksum(bh, -tmp);
903 affs_brelse(bh);
904 }
905 } else {
906 AFFS_I(inode)->i_blkcnt = 0;
907 AFFS_I(inode)->i_extcnt = 1;
908 }
909 AFFS_I(inode)->mmu_private = inode->i_size;
910 // unlock cache
911
912 while (ext_key) {
913 ext_bh = affs_bread(sb, ext_key);
914 size = AFFS_SB(sb)->s_hashsize;
915 if (size > blkcnt - blk)
916 size = blkcnt - blk;
917 for (i = 0; i < size; i++, blk++)
918 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
919 affs_free_block(sb, ext_key);
920 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
921 affs_brelse(ext_bh);
922 }
923 affs_free_prealloc(inode);
924}
925
926int affs_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
927{
928 struct inode *inode = filp->f_mapping->host;
929 int ret, err;
930
931 err = filemap_write_and_wait_range(inode->i_mapping, start, end);
932 if (err)
933 return err;
934
935 mutex_lock(&inode->i_mutex);
936 ret = write_inode_now(inode, 0);
937 err = sync_blockdev(inode->i_sb->s_bdev);
938 if (!ret)
939 ret = err;
940 mutex_unlock(&inode->i_mutex);
941 return ret;
942}
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
20static struct buffer_head *affs_get_extblock_slow(struct inode *inode, u32 ext);
21
22static int
23affs_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
31static int
32affs_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
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)
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
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;
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
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;
286 get_bh(bh);
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
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
356err_big:
357 affs_error(inode->i_sb, "get_block", "strange block request %llu",
358 (unsigned long long)block);
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}
377
378static int affs_read_folio(struct file *file, struct folio *folio)
379{
380 return block_read_full_folio(folio, affs_get_block);
381}
382
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) {
388 truncate_pagecache(inode, inode->i_size);
389 affs_truncate(inode);
390 }
391}
392
393static ssize_t
394affs_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
416static int affs_write_begin(struct file *file, struct address_space *mapping,
417 loff_t pos, unsigned len,
418 struct page **pagep, void **fsdata)
419{
420 int ret;
421
422 *pagep = NULL;
423 ret = cont_write_begin(file, mapping, pos, len, 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
432static 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
450static sector_t _affs_bmap(struct address_space *mapping, sector_t block)
451{
452 return generic_block_bmap(mapping,block,affs_get_block);
453}
454
455const struct address_space_operations affs_aops = {
456 .dirty_folio = block_dirty_folio,
457 .invalidate_folio = block_invalidate_folio,
458 .read_folio = affs_read_folio,
459 .writepage = affs_writepage,
460 .write_begin = affs_write_begin,
461 .write_end = affs_write_end,
462 .direct_IO = affs_direct_IO,
463 .bmap = _affs_bmap
464};
465
466static inline struct buffer_head *
467affs_bread_ino(struct inode *inode, int block, int create)
468{
469 struct buffer_head *bh, tmp_bh;
470 int err;
471
472 tmp_bh.b_state = 0;
473 err = affs_get_block(inode, block, &tmp_bh, create);
474 if (!err) {
475 bh = affs_bread(inode->i_sb, tmp_bh.b_blocknr);
476 if (bh) {
477 bh->b_state |= tmp_bh.b_state;
478 return bh;
479 }
480 err = -EIO;
481 }
482 return ERR_PTR(err);
483}
484
485static inline struct buffer_head *
486affs_getzeroblk_ino(struct inode *inode, int block)
487{
488 struct buffer_head *bh, tmp_bh;
489 int err;
490
491 tmp_bh.b_state = 0;
492 err = affs_get_block(inode, block, &tmp_bh, 1);
493 if (!err) {
494 bh = affs_getzeroblk(inode->i_sb, tmp_bh.b_blocknr);
495 if (bh) {
496 bh->b_state |= tmp_bh.b_state;
497 return bh;
498 }
499 err = -EIO;
500 }
501 return ERR_PTR(err);
502}
503
504static inline struct buffer_head *
505affs_getemptyblk_ino(struct inode *inode, int block)
506{
507 struct buffer_head *bh, tmp_bh;
508 int err;
509
510 tmp_bh.b_state = 0;
511 err = affs_get_block(inode, block, &tmp_bh, 1);
512 if (!err) {
513 bh = affs_getemptyblk(inode->i_sb, tmp_bh.b_blocknr);
514 if (bh) {
515 bh->b_state |= tmp_bh.b_state;
516 return bh;
517 }
518 err = -EIO;
519 }
520 return ERR_PTR(err);
521}
522
523static int
524affs_do_readpage_ofs(struct page *page, unsigned to, int create)
525{
526 struct inode *inode = page->mapping->host;
527 struct super_block *sb = inode->i_sb;
528 struct buffer_head *bh;
529 unsigned pos = 0;
530 u32 bidx, boff, bsize;
531 u32 tmp;
532
533 pr_debug("%s(%lu, %ld, 0, %d)\n", __func__, inode->i_ino,
534 page->index, to);
535 BUG_ON(to > PAGE_SIZE);
536 bsize = AFFS_SB(sb)->s_data_blksize;
537 tmp = page->index << PAGE_SHIFT;
538 bidx = tmp / bsize;
539 boff = tmp % bsize;
540
541 while (pos < to) {
542 bh = affs_bread_ino(inode, bidx, create);
543 if (IS_ERR(bh))
544 return PTR_ERR(bh);
545 tmp = min(bsize - boff, to - pos);
546 BUG_ON(pos + tmp > to || tmp > bsize);
547 memcpy_to_page(page, pos, AFFS_DATA(bh) + boff, tmp);
548 affs_brelse(bh);
549 bidx++;
550 pos += tmp;
551 boff = 0;
552 }
553 return 0;
554}
555
556static int
557affs_extent_file_ofs(struct inode *inode, u32 newsize)
558{
559 struct super_block *sb = inode->i_sb;
560 struct buffer_head *bh, *prev_bh;
561 u32 bidx, boff;
562 u32 size, bsize;
563 u32 tmp;
564
565 pr_debug("%s(%lu, %d)\n", __func__, inode->i_ino, newsize);
566 bsize = AFFS_SB(sb)->s_data_blksize;
567 bh = NULL;
568 size = AFFS_I(inode)->mmu_private;
569 bidx = size / bsize;
570 boff = size % bsize;
571 if (boff) {
572 bh = affs_bread_ino(inode, bidx, 0);
573 if (IS_ERR(bh))
574 return PTR_ERR(bh);
575 tmp = min(bsize - boff, newsize - size);
576 BUG_ON(boff + tmp > bsize || tmp > bsize);
577 memset(AFFS_DATA(bh) + boff, 0, tmp);
578 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp);
579 affs_fix_checksum(sb, bh);
580 mark_buffer_dirty_inode(bh, inode);
581 size += tmp;
582 bidx++;
583 } else if (bidx) {
584 bh = affs_bread_ino(inode, bidx - 1, 0);
585 if (IS_ERR(bh))
586 return PTR_ERR(bh);
587 }
588
589 while (size < newsize) {
590 prev_bh = bh;
591 bh = affs_getzeroblk_ino(inode, bidx);
592 if (IS_ERR(bh))
593 goto out;
594 tmp = min(bsize, newsize - size);
595 BUG_ON(tmp > bsize);
596 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
597 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
598 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
599 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
600 affs_fix_checksum(sb, bh);
601 bh->b_state &= ~(1UL << BH_New);
602 mark_buffer_dirty_inode(bh, inode);
603 if (prev_bh) {
604 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
605
606 if (tmp_next)
607 affs_warning(sb, "extent_file_ofs",
608 "next block already set for %d (%d)",
609 bidx, tmp_next);
610 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
611 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
612 mark_buffer_dirty_inode(prev_bh, inode);
613 affs_brelse(prev_bh);
614 }
615 size += bsize;
616 bidx++;
617 }
618 affs_brelse(bh);
619 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
620 return 0;
621
622out:
623 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
624 return PTR_ERR(bh);
625}
626
627static int
628affs_read_folio_ofs(struct file *file, struct folio *folio)
629{
630 struct page *page = &folio->page;
631 struct inode *inode = page->mapping->host;
632 u32 to;
633 int err;
634
635 pr_debug("%s(%lu, %ld)\n", __func__, inode->i_ino, page->index);
636 to = PAGE_SIZE;
637 if (((page->index + 1) << PAGE_SHIFT) > inode->i_size) {
638 to = inode->i_size & ~PAGE_MASK;
639 memset(page_address(page) + to, 0, PAGE_SIZE - to);
640 }
641
642 err = affs_do_readpage_ofs(page, to, 0);
643 if (!err)
644 SetPageUptodate(page);
645 unlock_page(page);
646 return err;
647}
648
649static int affs_write_begin_ofs(struct file *file, struct address_space *mapping,
650 loff_t pos, unsigned len,
651 struct page **pagep, void **fsdata)
652{
653 struct inode *inode = mapping->host;
654 struct page *page;
655 pgoff_t index;
656 int err = 0;
657
658 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos,
659 pos + len);
660 if (pos > AFFS_I(inode)->mmu_private) {
661 /* XXX: this probably leaves a too-big i_size in case of
662 * failure. Should really be updating i_size at write_end time
663 */
664 err = affs_extent_file_ofs(inode, pos);
665 if (err)
666 return err;
667 }
668
669 index = pos >> PAGE_SHIFT;
670 page = grab_cache_page_write_begin(mapping, index);
671 if (!page)
672 return -ENOMEM;
673 *pagep = page;
674
675 if (PageUptodate(page))
676 return 0;
677
678 /* XXX: inefficient but safe in the face of short writes */
679 err = affs_do_readpage_ofs(page, PAGE_SIZE, 1);
680 if (err) {
681 unlock_page(page);
682 put_page(page);
683 }
684 return err;
685}
686
687static int affs_write_end_ofs(struct file *file, struct address_space *mapping,
688 loff_t pos, unsigned len, unsigned copied,
689 struct page *page, void *fsdata)
690{
691 struct inode *inode = mapping->host;
692 struct super_block *sb = inode->i_sb;
693 struct buffer_head *bh, *prev_bh;
694 char *data;
695 u32 bidx, boff, bsize;
696 unsigned from, to;
697 u32 tmp;
698 int written;
699
700 from = pos & (PAGE_SIZE - 1);
701 to = from + len;
702 /*
703 * XXX: not sure if this can handle short copies (len < copied), but
704 * we don't have to, because the page should always be uptodate here,
705 * due to write_begin.
706 */
707
708 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos,
709 pos + len);
710 bsize = AFFS_SB(sb)->s_data_blksize;
711 data = page_address(page);
712
713 bh = NULL;
714 written = 0;
715 tmp = (page->index << PAGE_SHIFT) + from;
716 bidx = tmp / bsize;
717 boff = tmp % bsize;
718 if (boff) {
719 bh = affs_bread_ino(inode, bidx, 0);
720 if (IS_ERR(bh)) {
721 written = PTR_ERR(bh);
722 goto err_first_bh;
723 }
724 tmp = min(bsize - boff, to - from);
725 BUG_ON(boff + tmp > bsize || tmp > bsize);
726 memcpy(AFFS_DATA(bh) + boff, data + from, tmp);
727 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp);
728 affs_fix_checksum(sb, bh);
729 mark_buffer_dirty_inode(bh, inode);
730 written += tmp;
731 from += tmp;
732 bidx++;
733 } else if (bidx) {
734 bh = affs_bread_ino(inode, bidx - 1, 0);
735 if (IS_ERR(bh)) {
736 written = PTR_ERR(bh);
737 goto err_first_bh;
738 }
739 }
740 while (from + bsize <= to) {
741 prev_bh = bh;
742 bh = affs_getemptyblk_ino(inode, bidx);
743 if (IS_ERR(bh))
744 goto err_bh;
745 memcpy(AFFS_DATA(bh), data + from, bsize);
746 if (buffer_new(bh)) {
747 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
748 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
749 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
750 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(bsize);
751 AFFS_DATA_HEAD(bh)->next = 0;
752 bh->b_state &= ~(1UL << BH_New);
753 if (prev_bh) {
754 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
755
756 if (tmp_next)
757 affs_warning(sb, "commit_write_ofs",
758 "next block already set for %d (%d)",
759 bidx, tmp_next);
760 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
761 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
762 mark_buffer_dirty_inode(prev_bh, inode);
763 }
764 }
765 affs_brelse(prev_bh);
766 affs_fix_checksum(sb, bh);
767 mark_buffer_dirty_inode(bh, inode);
768 written += bsize;
769 from += bsize;
770 bidx++;
771 }
772 if (from < to) {
773 prev_bh = bh;
774 bh = affs_bread_ino(inode, bidx, 1);
775 if (IS_ERR(bh))
776 goto err_bh;
777 tmp = min(bsize, to - from);
778 BUG_ON(tmp > bsize);
779 memcpy(AFFS_DATA(bh), data + from, tmp);
780 if (buffer_new(bh)) {
781 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
782 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
783 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
784 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
785 AFFS_DATA_HEAD(bh)->next = 0;
786 bh->b_state &= ~(1UL << BH_New);
787 if (prev_bh) {
788 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
789
790 if (tmp_next)
791 affs_warning(sb, "commit_write_ofs",
792 "next block already set for %d (%d)",
793 bidx, tmp_next);
794 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
795 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
796 mark_buffer_dirty_inode(prev_bh, inode);
797 }
798 } else if (be32_to_cpu(AFFS_DATA_HEAD(bh)->size) < tmp)
799 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
800 affs_brelse(prev_bh);
801 affs_fix_checksum(sb, bh);
802 mark_buffer_dirty_inode(bh, inode);
803 written += tmp;
804 from += tmp;
805 bidx++;
806 }
807 SetPageUptodate(page);
808
809done:
810 affs_brelse(bh);
811 tmp = (page->index << PAGE_SHIFT) + from;
812 if (tmp > inode->i_size)
813 inode->i_size = AFFS_I(inode)->mmu_private = tmp;
814
815 /* Clear Archived bit on file writes, as AmigaOS would do */
816 if (AFFS_I(inode)->i_protect & FIBF_ARCHIVED) {
817 AFFS_I(inode)->i_protect &= ~FIBF_ARCHIVED;
818 mark_inode_dirty(inode);
819 }
820
821err_first_bh:
822 unlock_page(page);
823 put_page(page);
824
825 return written;
826
827err_bh:
828 bh = prev_bh;
829 if (!written)
830 written = PTR_ERR(bh);
831 goto done;
832}
833
834const struct address_space_operations affs_aops_ofs = {
835 .dirty_folio = block_dirty_folio,
836 .invalidate_folio = block_invalidate_folio,
837 .read_folio = affs_read_folio_ofs,
838 //.writepage = affs_writepage_ofs,
839 .write_begin = affs_write_begin_ofs,
840 .write_end = affs_write_end_ofs
841};
842
843/* Free any preallocated blocks. */
844
845void
846affs_free_prealloc(struct inode *inode)
847{
848 struct super_block *sb = inode->i_sb;
849
850 pr_debug("free_prealloc(ino=%lu)\n", inode->i_ino);
851
852 while (AFFS_I(inode)->i_pa_cnt) {
853 AFFS_I(inode)->i_pa_cnt--;
854 affs_free_block(sb, ++AFFS_I(inode)->i_lastalloc);
855 }
856}
857
858/* Truncate (or enlarge) a file to the requested size. */
859
860void
861affs_truncate(struct inode *inode)
862{
863 struct super_block *sb = inode->i_sb;
864 u32 ext, ext_key;
865 u32 last_blk, blkcnt, blk;
866 u32 size;
867 struct buffer_head *ext_bh;
868 int i;
869
870 pr_debug("truncate(inode=%lu, oldsize=%llu, newsize=%llu)\n",
871 inode->i_ino, AFFS_I(inode)->mmu_private, inode->i_size);
872
873 last_blk = 0;
874 ext = 0;
875 if (inode->i_size) {
876 last_blk = ((u32)inode->i_size - 1) / AFFS_SB(sb)->s_data_blksize;
877 ext = last_blk / AFFS_SB(sb)->s_hashsize;
878 }
879
880 if (inode->i_size > AFFS_I(inode)->mmu_private) {
881 struct address_space *mapping = inode->i_mapping;
882 struct page *page;
883 void *fsdata = NULL;
884 loff_t isize = inode->i_size;
885 int res;
886
887 res = mapping->a_ops->write_begin(NULL, mapping, isize, 0, &page, &fsdata);
888 if (!res)
889 res = mapping->a_ops->write_end(NULL, mapping, isize, 0, 0, page, fsdata);
890 else
891 inode->i_size = AFFS_I(inode)->mmu_private;
892 mark_inode_dirty(inode);
893 return;
894 } else if (inode->i_size == AFFS_I(inode)->mmu_private)
895 return;
896
897 // lock cache
898 ext_bh = affs_get_extblock(inode, ext);
899 if (IS_ERR(ext_bh)) {
900 affs_warning(sb, "truncate",
901 "unexpected read error for ext block %u (%ld)",
902 ext, PTR_ERR(ext_bh));
903 return;
904 }
905 if (AFFS_I(inode)->i_lc) {
906 /* clear linear cache */
907 i = (ext + 1) >> AFFS_I(inode)->i_lc_shift;
908 if (AFFS_I(inode)->i_lc_size > i) {
909 AFFS_I(inode)->i_lc_size = i;
910 for (; i < AFFS_LC_SIZE; i++)
911 AFFS_I(inode)->i_lc[i] = 0;
912 }
913 /* clear associative cache */
914 for (i = 0; i < AFFS_AC_SIZE; i++)
915 if (AFFS_I(inode)->i_ac[i].ext >= ext)
916 AFFS_I(inode)->i_ac[i].ext = 0;
917 }
918 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
919
920 blkcnt = AFFS_I(inode)->i_blkcnt;
921 i = 0;
922 blk = last_blk;
923 if (inode->i_size) {
924 i = last_blk % AFFS_SB(sb)->s_hashsize + 1;
925 blk++;
926 } else
927 AFFS_HEAD(ext_bh)->first_data = 0;
928 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(i);
929 size = AFFS_SB(sb)->s_hashsize;
930 if (size > blkcnt - blk + i)
931 size = blkcnt - blk + i;
932 for (; i < size; i++, blk++) {
933 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
934 AFFS_BLOCK(sb, ext_bh, i) = 0;
935 }
936 AFFS_TAIL(sb, ext_bh)->extension = 0;
937 affs_fix_checksum(sb, ext_bh);
938 mark_buffer_dirty_inode(ext_bh, inode);
939 affs_brelse(ext_bh);
940
941 if (inode->i_size) {
942 AFFS_I(inode)->i_blkcnt = last_blk + 1;
943 AFFS_I(inode)->i_extcnt = ext + 1;
944 if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_OFS)) {
945 struct buffer_head *bh = affs_bread_ino(inode, last_blk, 0);
946 u32 tmp;
947 if (IS_ERR(bh)) {
948 affs_warning(sb, "truncate",
949 "unexpected read error for last block %u (%ld)",
950 ext, PTR_ERR(bh));
951 return;
952 }
953 tmp = be32_to_cpu(AFFS_DATA_HEAD(bh)->next);
954 AFFS_DATA_HEAD(bh)->next = 0;
955 affs_adjust_checksum(bh, -tmp);
956 affs_brelse(bh);
957 }
958 } else {
959 AFFS_I(inode)->i_blkcnt = 0;
960 AFFS_I(inode)->i_extcnt = 1;
961 }
962 AFFS_I(inode)->mmu_private = inode->i_size;
963 // unlock cache
964
965 while (ext_key) {
966 ext_bh = affs_bread(sb, ext_key);
967 size = AFFS_SB(sb)->s_hashsize;
968 if (size > blkcnt - blk)
969 size = blkcnt - blk;
970 for (i = 0; i < size; i++, blk++)
971 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
972 affs_free_block(sb, ext_key);
973 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
974 affs_brelse(ext_bh);
975 }
976 affs_free_prealloc(inode);
977}
978
979int affs_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
980{
981 struct inode *inode = filp->f_mapping->host;
982 int ret, err;
983
984 err = file_write_and_wait_range(filp, start, end);
985 if (err)
986 return err;
987
988 inode_lock(inode);
989 ret = write_inode_now(inode, 0);
990 err = sync_blockdev(inode->i_sb->s_bdev);
991 if (!ret)
992 ret = err;
993 inode_unlock(inode);
994 return ret;
995}
996const struct file_operations affs_file_operations = {
997 .llseek = generic_file_llseek,
998 .read_iter = generic_file_read_iter,
999 .write_iter = generic_file_write_iter,
1000 .mmap = generic_file_mmap,
1001 .open = affs_file_open,
1002 .release = affs_file_release,
1003 .fsync = affs_file_fsync,
1004 .splice_read = generic_file_splice_read,
1005};
1006
1007const struct inode_operations affs_file_inode_operations = {
1008 .setattr = affs_notify_change,
1009};