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 <linux/mpage.h>
19 #include "affs.h"
20
21 static struct buffer_head *affs_get_extblock_slow(struct inode *inode, u32 ext);
22
23 static int
affs_file_open(struct inode * inode,struct file * filp)24 affs_file_open(struct inode *inode, struct file *filp)
25 {
26 pr_debug("open(%lu,%d)\n",
27 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
28 atomic_inc(&AFFS_I(inode)->i_opencnt);
29 return 0;
30 }
31
32 static int
affs_file_release(struct inode * inode,struct file * filp)33 affs_file_release(struct inode *inode, struct file *filp)
34 {
35 pr_debug("release(%lu, %d)\n",
36 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
37
38 if (atomic_dec_and_test(&AFFS_I(inode)->i_opencnt)) {
39 inode_lock(inode);
40 if (inode->i_size != AFFS_I(inode)->mmu_private)
41 affs_truncate(inode);
42 affs_free_prealloc(inode);
43 inode_unlock(inode);
44 }
45
46 return 0;
47 }
48
49 static int
affs_grow_extcache(struct inode * inode,u32 lc_idx)50 affs_grow_extcache(struct inode *inode, u32 lc_idx)
51 {
52 struct super_block *sb = inode->i_sb;
53 struct buffer_head *bh;
54 u32 lc_max;
55 int i, j, key;
56
57 if (!AFFS_I(inode)->i_lc) {
58 char *ptr = (char *)get_zeroed_page(GFP_NOFS);
59 if (!ptr)
60 return -ENOMEM;
61 AFFS_I(inode)->i_lc = (u32 *)ptr;
62 AFFS_I(inode)->i_ac = (struct affs_ext_key *)(ptr + AFFS_CACHE_SIZE / 2);
63 }
64
65 lc_max = AFFS_LC_SIZE << AFFS_I(inode)->i_lc_shift;
66
67 if (AFFS_I(inode)->i_extcnt > lc_max) {
68 u32 lc_shift, lc_mask, tmp, off;
69
70 /* need to recalculate linear cache, start from old size */
71 lc_shift = AFFS_I(inode)->i_lc_shift;
72 tmp = (AFFS_I(inode)->i_extcnt / AFFS_LC_SIZE) >> lc_shift;
73 for (; tmp; tmp >>= 1)
74 lc_shift++;
75 lc_mask = (1 << lc_shift) - 1;
76
77 /* fix idx and old size to new shift */
78 lc_idx >>= (lc_shift - AFFS_I(inode)->i_lc_shift);
79 AFFS_I(inode)->i_lc_size >>= (lc_shift - AFFS_I(inode)->i_lc_shift);
80
81 /* first shrink old cache to make more space */
82 off = 1 << (lc_shift - AFFS_I(inode)->i_lc_shift);
83 for (i = 1, j = off; j < AFFS_LC_SIZE; i++, j += off)
84 AFFS_I(inode)->i_ac[i] = AFFS_I(inode)->i_ac[j];
85
86 AFFS_I(inode)->i_lc_shift = lc_shift;
87 AFFS_I(inode)->i_lc_mask = lc_mask;
88 }
89
90 /* fill cache to the needed index */
91 i = AFFS_I(inode)->i_lc_size;
92 AFFS_I(inode)->i_lc_size = lc_idx + 1;
93 for (; i <= lc_idx; i++) {
94 if (!i) {
95 AFFS_I(inode)->i_lc[0] = inode->i_ino;
96 continue;
97 }
98 key = AFFS_I(inode)->i_lc[i - 1];
99 j = AFFS_I(inode)->i_lc_mask + 1;
100 // unlock cache
101 for (; j > 0; j--) {
102 bh = affs_bread(sb, key);
103 if (!bh)
104 goto err;
105 key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
106 affs_brelse(bh);
107 }
108 // lock cache
109 AFFS_I(inode)->i_lc[i] = key;
110 }
111
112 return 0;
113
114 err:
115 // lock cache
116 return -EIO;
117 }
118
119 static struct buffer_head *
affs_alloc_extblock(struct inode * inode,struct buffer_head * bh,u32 ext)120 affs_alloc_extblock(struct inode *inode, struct buffer_head *bh, u32 ext)
121 {
122 struct super_block *sb = inode->i_sb;
123 struct buffer_head *new_bh;
124 u32 blocknr, tmp;
125
126 blocknr = affs_alloc_block(inode, bh->b_blocknr);
127 if (!blocknr)
128 return ERR_PTR(-ENOSPC);
129
130 new_bh = affs_getzeroblk(sb, blocknr);
131 if (!new_bh) {
132 affs_free_block(sb, blocknr);
133 return ERR_PTR(-EIO);
134 }
135
136 AFFS_HEAD(new_bh)->ptype = cpu_to_be32(T_LIST);
137 AFFS_HEAD(new_bh)->key = cpu_to_be32(blocknr);
138 AFFS_TAIL(sb, new_bh)->stype = cpu_to_be32(ST_FILE);
139 AFFS_TAIL(sb, new_bh)->parent = cpu_to_be32(inode->i_ino);
140 affs_fix_checksum(sb, new_bh);
141
142 mark_buffer_dirty_inode(new_bh, inode);
143
144 tmp = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
145 if (tmp)
146 affs_warning(sb, "alloc_ext", "previous extension set (%x)", tmp);
147 AFFS_TAIL(sb, bh)->extension = cpu_to_be32(blocknr);
148 affs_adjust_checksum(bh, blocknr - tmp);
149 mark_buffer_dirty_inode(bh, inode);
150
151 AFFS_I(inode)->i_extcnt++;
152 mark_inode_dirty(inode);
153
154 return new_bh;
155 }
156
157 static inline struct buffer_head *
affs_get_extblock(struct inode * inode,u32 ext)158 affs_get_extblock(struct inode *inode, u32 ext)
159 {
160 /* inline the simplest case: same extended block as last time */
161 struct buffer_head *bh = AFFS_I(inode)->i_ext_bh;
162 if (ext == AFFS_I(inode)->i_ext_last)
163 get_bh(bh);
164 else
165 /* we have to do more (not inlined) */
166 bh = affs_get_extblock_slow(inode, ext);
167
168 return bh;
169 }
170
171 static struct buffer_head *
affs_get_extblock_slow(struct inode * inode,u32 ext)172 affs_get_extblock_slow(struct inode *inode, u32 ext)
173 {
174 struct super_block *sb = inode->i_sb;
175 struct buffer_head *bh;
176 u32 ext_key;
177 u32 lc_idx, lc_off, ac_idx;
178 u32 tmp, idx;
179
180 if (ext == AFFS_I(inode)->i_ext_last + 1) {
181 /* read the next extended block from the current one */
182 bh = AFFS_I(inode)->i_ext_bh;
183 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
184 if (ext < AFFS_I(inode)->i_extcnt)
185 goto read_ext;
186 BUG_ON(ext > AFFS_I(inode)->i_extcnt);
187 bh = affs_alloc_extblock(inode, bh, ext);
188 if (IS_ERR(bh))
189 return bh;
190 goto store_ext;
191 }
192
193 if (ext == 0) {
194 /* we seek back to the file header block */
195 ext_key = inode->i_ino;
196 goto read_ext;
197 }
198
199 if (ext >= AFFS_I(inode)->i_extcnt) {
200 struct buffer_head *prev_bh;
201
202 /* allocate a new extended block */
203 BUG_ON(ext > AFFS_I(inode)->i_extcnt);
204
205 /* get previous extended block */
206 prev_bh = affs_get_extblock(inode, ext - 1);
207 if (IS_ERR(prev_bh))
208 return prev_bh;
209 bh = affs_alloc_extblock(inode, prev_bh, ext);
210 affs_brelse(prev_bh);
211 if (IS_ERR(bh))
212 return bh;
213 goto store_ext;
214 }
215
216 again:
217 /* check if there is an extended cache and whether it's large enough */
218 lc_idx = ext >> AFFS_I(inode)->i_lc_shift;
219 lc_off = ext & AFFS_I(inode)->i_lc_mask;
220
221 if (lc_idx >= AFFS_I(inode)->i_lc_size) {
222 int err;
223
224 err = affs_grow_extcache(inode, lc_idx);
225 if (err)
226 return ERR_PTR(err);
227 goto again;
228 }
229
230 /* every n'th key we find in the linear cache */
231 if (!lc_off) {
232 ext_key = AFFS_I(inode)->i_lc[lc_idx];
233 goto read_ext;
234 }
235
236 /* maybe it's still in the associative cache */
237 ac_idx = (ext - lc_idx - 1) & AFFS_AC_MASK;
238 if (AFFS_I(inode)->i_ac[ac_idx].ext == ext) {
239 ext_key = AFFS_I(inode)->i_ac[ac_idx].key;
240 goto read_ext;
241 }
242
243 /* try to find one of the previous extended blocks */
244 tmp = ext;
245 idx = ac_idx;
246 while (--tmp, --lc_off > 0) {
247 idx = (idx - 1) & AFFS_AC_MASK;
248 if (AFFS_I(inode)->i_ac[idx].ext == tmp) {
249 ext_key = AFFS_I(inode)->i_ac[idx].key;
250 goto find_ext;
251 }
252 }
253
254 /* fall back to the linear cache */
255 ext_key = AFFS_I(inode)->i_lc[lc_idx];
256 find_ext:
257 /* read all extended blocks until we find the one we need */
258 //unlock cache
259 do {
260 bh = affs_bread(sb, ext_key);
261 if (!bh)
262 goto err_bread;
263 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
264 affs_brelse(bh);
265 tmp++;
266 } while (tmp < ext);
267 //lock cache
268
269 /* store it in the associative cache */
270 // recalculate ac_idx?
271 AFFS_I(inode)->i_ac[ac_idx].ext = ext;
272 AFFS_I(inode)->i_ac[ac_idx].key = ext_key;
273
274 read_ext:
275 /* finally read the right extended block */
276 //unlock cache
277 bh = affs_bread(sb, ext_key);
278 if (!bh)
279 goto err_bread;
280 //lock cache
281
282 store_ext:
283 /* release old cached extended block and store the new one */
284 affs_brelse(AFFS_I(inode)->i_ext_bh);
285 AFFS_I(inode)->i_ext_last = ext;
286 AFFS_I(inode)->i_ext_bh = bh;
287 get_bh(bh);
288
289 return bh;
290
291 err_bread:
292 affs_brelse(bh);
293 return ERR_PTR(-EIO);
294 }
295
296 static int
affs_get_block(struct inode * inode,sector_t block,struct buffer_head * bh_result,int create)297 affs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh_result, int create)
298 {
299 struct super_block *sb = inode->i_sb;
300 struct buffer_head *ext_bh;
301 u32 ext;
302
303 pr_debug("%s(%lu, %llu)\n", __func__, inode->i_ino,
304 (unsigned long long)block);
305
306 BUG_ON(block > (sector_t)0x7fffffffUL);
307
308 if (block >= AFFS_I(inode)->i_blkcnt) {
309 if (block > AFFS_I(inode)->i_blkcnt || !create)
310 goto err_big;
311 } else
312 create = 0;
313
314 //lock cache
315 affs_lock_ext(inode);
316
317 ext = (u32)block / AFFS_SB(sb)->s_hashsize;
318 block -= ext * AFFS_SB(sb)->s_hashsize;
319 ext_bh = affs_get_extblock(inode, ext);
320 if (IS_ERR(ext_bh))
321 goto err_ext;
322 map_bh(bh_result, sb, (sector_t)be32_to_cpu(AFFS_BLOCK(sb, ext_bh, block)));
323
324 if (create) {
325 u32 blocknr = affs_alloc_block(inode, ext_bh->b_blocknr);
326 if (!blocknr)
327 goto err_alloc;
328 set_buffer_new(bh_result);
329 AFFS_I(inode)->mmu_private += AFFS_SB(sb)->s_data_blksize;
330 AFFS_I(inode)->i_blkcnt++;
331
332 /* store new block */
333 if (bh_result->b_blocknr)
334 affs_warning(sb, "get_block",
335 "block already set (%llx)",
336 (unsigned long long)bh_result->b_blocknr);
337 AFFS_BLOCK(sb, ext_bh, block) = cpu_to_be32(blocknr);
338 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(block + 1);
339 affs_adjust_checksum(ext_bh, blocknr - bh_result->b_blocknr + 1);
340 bh_result->b_blocknr = blocknr;
341
342 if (!block) {
343 /* insert first block into header block */
344 u32 tmp = be32_to_cpu(AFFS_HEAD(ext_bh)->first_data);
345 if (tmp)
346 affs_warning(sb, "get_block", "first block already set (%d)", tmp);
347 AFFS_HEAD(ext_bh)->first_data = cpu_to_be32(blocknr);
348 affs_adjust_checksum(ext_bh, blocknr - tmp);
349 }
350 }
351
352 affs_brelse(ext_bh);
353 //unlock cache
354 affs_unlock_ext(inode);
355 return 0;
356
357 err_big:
358 affs_error(inode->i_sb, "get_block", "strange block request %llu",
359 (unsigned long long)block);
360 return -EIO;
361 err_ext:
362 // unlock cache
363 affs_unlock_ext(inode);
364 return PTR_ERR(ext_bh);
365 err_alloc:
366 brelse(ext_bh);
367 clear_buffer_mapped(bh_result);
368 bh_result->b_bdev = NULL;
369 // unlock cache
370 affs_unlock_ext(inode);
371 return -ENOSPC;
372 }
373
affs_writepages(struct address_space * mapping,struct writeback_control * wbc)374 static int affs_writepages(struct address_space *mapping,
375 struct writeback_control *wbc)
376 {
377 return mpage_writepages(mapping, wbc, affs_get_block);
378 }
379
affs_read_folio(struct file * file,struct folio * folio)380 static int affs_read_folio(struct file *file, struct folio *folio)
381 {
382 return block_read_full_folio(folio, affs_get_block);
383 }
384
affs_write_failed(struct address_space * mapping,loff_t to)385 static void affs_write_failed(struct address_space *mapping, loff_t to)
386 {
387 struct inode *inode = mapping->host;
388
389 if (to > inode->i_size) {
390 truncate_pagecache(inode, inode->i_size);
391 affs_truncate(inode);
392 }
393 }
394
395 static ssize_t
affs_direct_IO(struct kiocb * iocb,struct iov_iter * iter)396 affs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
397 {
398 struct file *file = iocb->ki_filp;
399 struct address_space *mapping = file->f_mapping;
400 struct inode *inode = mapping->host;
401 size_t count = iov_iter_count(iter);
402 loff_t offset = iocb->ki_pos;
403 ssize_t ret;
404
405 if (iov_iter_rw(iter) == WRITE) {
406 loff_t size = offset + count;
407
408 if (AFFS_I(inode)->mmu_private < size)
409 return 0;
410 }
411
412 ret = blockdev_direct_IO(iocb, inode, iter, affs_get_block);
413 if (ret < 0 && iov_iter_rw(iter) == WRITE)
414 affs_write_failed(mapping, offset + count);
415 return ret;
416 }
417
affs_write_begin(const struct kiocb * iocb,struct address_space * mapping,loff_t pos,unsigned len,struct folio ** foliop,void ** fsdata)418 static int affs_write_begin(const struct kiocb *iocb,
419 struct address_space *mapping,
420 loff_t pos, unsigned len,
421 struct folio **foliop, void **fsdata)
422 {
423 int ret;
424
425 ret = cont_write_begin(iocb, mapping, pos, len, foliop, fsdata,
426 affs_get_block,
427 &AFFS_I(mapping->host)->mmu_private);
428 if (unlikely(ret))
429 affs_write_failed(mapping, pos + len);
430
431 return ret;
432 }
433
affs_write_end(const struct kiocb * iocb,struct address_space * mapping,loff_t pos,unsigned int len,unsigned int copied,struct folio * folio,void * fsdata)434 static int affs_write_end(const struct kiocb *iocb,
435 struct address_space *mapping, loff_t pos,
436 unsigned int len, unsigned int copied,
437 struct folio *folio, void *fsdata)
438 {
439 struct inode *inode = mapping->host;
440 int ret;
441
442 ret = generic_write_end(iocb, mapping, pos, len, copied, folio, fsdata);
443
444 /* Clear Archived bit on file writes, as AmigaOS would do */
445 if (AFFS_I(inode)->i_protect & FIBF_ARCHIVED) {
446 AFFS_I(inode)->i_protect &= ~FIBF_ARCHIVED;
447 mark_inode_dirty(inode);
448 }
449
450 return ret;
451 }
452
_affs_bmap(struct address_space * mapping,sector_t block)453 static sector_t _affs_bmap(struct address_space *mapping, sector_t block)
454 {
455 return generic_block_bmap(mapping,block,affs_get_block);
456 }
457
458 const struct address_space_operations affs_aops = {
459 .dirty_folio = block_dirty_folio,
460 .invalidate_folio = block_invalidate_folio,
461 .read_folio = affs_read_folio,
462 .writepages = affs_writepages,
463 .write_begin = affs_write_begin,
464 .write_end = affs_write_end,
465 .direct_IO = affs_direct_IO,
466 .migrate_folio = buffer_migrate_folio,
467 .bmap = _affs_bmap
468 };
469
470 static inline struct buffer_head *
affs_bread_ino(struct inode * inode,int block,int create)471 affs_bread_ino(struct inode *inode, int block, int create)
472 {
473 struct buffer_head *bh, tmp_bh;
474 int err;
475
476 tmp_bh.b_state = 0;
477 err = affs_get_block(inode, block, &tmp_bh, create);
478 if (!err) {
479 bh = affs_bread(inode->i_sb, tmp_bh.b_blocknr);
480 if (bh) {
481 bh->b_state |= tmp_bh.b_state;
482 return bh;
483 }
484 err = -EIO;
485 }
486 return ERR_PTR(err);
487 }
488
489 static inline struct buffer_head *
affs_getzeroblk_ino(struct inode * inode,int block)490 affs_getzeroblk_ino(struct inode *inode, int block)
491 {
492 struct buffer_head *bh, tmp_bh;
493 int err;
494
495 tmp_bh.b_state = 0;
496 err = affs_get_block(inode, block, &tmp_bh, 1);
497 if (!err) {
498 bh = affs_getzeroblk(inode->i_sb, tmp_bh.b_blocknr);
499 if (bh) {
500 bh->b_state |= tmp_bh.b_state;
501 return bh;
502 }
503 err = -EIO;
504 }
505 return ERR_PTR(err);
506 }
507
508 static inline struct buffer_head *
affs_getemptyblk_ino(struct inode * inode,int block)509 affs_getemptyblk_ino(struct inode *inode, int block)
510 {
511 struct buffer_head *bh, tmp_bh;
512 int err;
513
514 tmp_bh.b_state = 0;
515 err = affs_get_block(inode, block, &tmp_bh, 1);
516 if (!err) {
517 bh = affs_getemptyblk(inode->i_sb, tmp_bh.b_blocknr);
518 if (bh) {
519 bh->b_state |= tmp_bh.b_state;
520 return bh;
521 }
522 err = -EIO;
523 }
524 return ERR_PTR(err);
525 }
526
affs_do_read_folio_ofs(struct folio * folio,size_t to,int create)527 static int affs_do_read_folio_ofs(struct folio *folio, size_t to, int create)
528 {
529 struct inode *inode = folio->mapping->host;
530 struct super_block *sb = inode->i_sb;
531 struct buffer_head *bh;
532 size_t pos = 0;
533 size_t bidx, boff, bsize;
534 u32 tmp;
535
536 pr_debug("%s(%lu, %ld, 0, %zu)\n", __func__, inode->i_ino,
537 folio->index, to);
538 BUG_ON(to > folio_size(folio));
539 bsize = AFFS_SB(sb)->s_data_blksize;
540 tmp = folio_pos(folio);
541 bidx = tmp / bsize;
542 boff = tmp % bsize;
543
544 while (pos < to) {
545 bh = affs_bread_ino(inode, bidx, create);
546 if (IS_ERR(bh))
547 return PTR_ERR(bh);
548 tmp = min(bsize - boff, to - pos);
549 BUG_ON(pos + tmp > to || tmp > bsize);
550 memcpy_to_folio(folio, pos, AFFS_DATA(bh) + boff, tmp);
551 affs_brelse(bh);
552 bidx++;
553 pos += tmp;
554 boff = 0;
555 }
556 return 0;
557 }
558
559 static int
affs_extent_file_ofs(struct inode * inode,u32 newsize)560 affs_extent_file_ofs(struct inode *inode, u32 newsize)
561 {
562 struct super_block *sb = inode->i_sb;
563 struct buffer_head *bh, *prev_bh;
564 u32 bidx, boff;
565 u32 size, bsize;
566 u32 tmp;
567
568 pr_debug("%s(%lu, %d)\n", __func__, inode->i_ino, newsize);
569 bsize = AFFS_SB(sb)->s_data_blksize;
570 bh = NULL;
571 size = AFFS_I(inode)->mmu_private;
572 bidx = size / bsize;
573 boff = size % bsize;
574 if (boff) {
575 bh = affs_bread_ino(inode, bidx, 0);
576 if (IS_ERR(bh))
577 return PTR_ERR(bh);
578 tmp = min(bsize - boff, newsize - size);
579 BUG_ON(boff + tmp > bsize || tmp > bsize);
580 memset(AFFS_DATA(bh) + boff, 0, tmp);
581 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp);
582 affs_fix_checksum(sb, bh);
583 mark_buffer_dirty_inode(bh, inode);
584 size += tmp;
585 bidx++;
586 } else if (bidx) {
587 bh = affs_bread_ino(inode, bidx - 1, 0);
588 if (IS_ERR(bh))
589 return PTR_ERR(bh);
590 }
591
592 while (size < newsize) {
593 prev_bh = bh;
594 bh = affs_getzeroblk_ino(inode, bidx);
595 if (IS_ERR(bh))
596 goto out;
597 tmp = min(bsize, newsize - size);
598 BUG_ON(tmp > bsize);
599 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
600 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
601 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx + 1);
602 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
603 affs_fix_checksum(sb, bh);
604 bh->b_state &= ~(1UL << BH_New);
605 mark_buffer_dirty_inode(bh, inode);
606 if (prev_bh) {
607 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
608
609 if (tmp_next)
610 affs_warning(sb, "extent_file_ofs",
611 "next block already set for %d (%d)",
612 bidx, tmp_next);
613 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
614 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
615 mark_buffer_dirty_inode(prev_bh, inode);
616 affs_brelse(prev_bh);
617 }
618 size += bsize;
619 bidx++;
620 }
621 affs_brelse(bh);
622 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
623 return 0;
624
625 out:
626 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
627 return PTR_ERR(bh);
628 }
629
affs_read_folio_ofs(struct file * file,struct folio * folio)630 static int affs_read_folio_ofs(struct file *file, struct folio *folio)
631 {
632 struct inode *inode = folio->mapping->host;
633 size_t to;
634 int err;
635
636 pr_debug("%s(%lu, %ld)\n", __func__, inode->i_ino, folio->index);
637 to = folio_size(folio);
638 if (folio_pos(folio) + to > inode->i_size) {
639 to = inode->i_size - folio_pos(folio);
640 folio_zero_segment(folio, to, folio_size(folio));
641 }
642
643 err = affs_do_read_folio_ofs(folio, to, 0);
644 if (!err)
645 folio_mark_uptodate(folio);
646 folio_unlock(folio);
647 return err;
648 }
649
affs_write_begin_ofs(const struct kiocb * iocb,struct address_space * mapping,loff_t pos,unsigned len,struct folio ** foliop,void ** fsdata)650 static int affs_write_begin_ofs(const struct kiocb *iocb,
651 struct address_space *mapping,
652 loff_t pos, unsigned len,
653 struct folio **foliop, void **fsdata)
654 {
655 struct inode *inode = mapping->host;
656 struct folio *folio;
657 pgoff_t index;
658 int err = 0;
659
660 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos,
661 pos + len);
662 if (pos > AFFS_I(inode)->mmu_private) {
663 /* XXX: this probably leaves a too-big i_size in case of
664 * failure. Should really be updating i_size at write_end time
665 */
666 err = affs_extent_file_ofs(inode, pos);
667 if (err)
668 return err;
669 }
670
671 index = pos >> PAGE_SHIFT;
672 folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN,
673 mapping_gfp_mask(mapping));
674 if (IS_ERR(folio))
675 return PTR_ERR(folio);
676 *foliop = folio;
677
678 if (folio_test_uptodate(folio))
679 return 0;
680
681 /* XXX: inefficient but safe in the face of short writes */
682 err = affs_do_read_folio_ofs(folio, folio_size(folio), 1);
683 if (err) {
684 folio_unlock(folio);
685 folio_put(folio);
686 }
687 return err;
688 }
689
affs_write_end_ofs(const struct kiocb * iocb,struct address_space * mapping,loff_t pos,unsigned len,unsigned copied,struct folio * folio,void * fsdata)690 static int affs_write_end_ofs(const struct kiocb *iocb,
691 struct address_space *mapping,
692 loff_t pos, unsigned len, unsigned copied,
693 struct folio *folio, void *fsdata)
694 {
695 struct inode *inode = mapping->host;
696 struct super_block *sb = inode->i_sb;
697 struct buffer_head *bh, *prev_bh;
698 char *data;
699 u32 bidx, boff, bsize;
700 unsigned from, to;
701 u32 tmp;
702 int written;
703
704 from = pos & (PAGE_SIZE - 1);
705 to = from + len;
706 /*
707 * XXX: not sure if this can handle short copies (len < copied), but
708 * we don't have to, because the folio should always be uptodate here,
709 * due to write_begin.
710 */
711
712 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos,
713 pos + len);
714 bsize = AFFS_SB(sb)->s_data_blksize;
715 data = folio_address(folio);
716
717 bh = NULL;
718 written = 0;
719 tmp = (folio->index << PAGE_SHIFT) + from;
720 bidx = tmp / bsize;
721 boff = tmp % bsize;
722 if (boff) {
723 bh = affs_bread_ino(inode, bidx, 0);
724 if (IS_ERR(bh)) {
725 written = PTR_ERR(bh);
726 goto err_first_bh;
727 }
728 tmp = min(bsize - boff, to - from);
729 BUG_ON(boff + tmp > bsize || tmp > bsize);
730 memcpy(AFFS_DATA(bh) + boff, data + from, tmp);
731 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(
732 max(boff + tmp, be32_to_cpu(AFFS_DATA_HEAD(bh)->size)));
733 affs_fix_checksum(sb, bh);
734 mark_buffer_dirty_inode(bh, inode);
735 written += tmp;
736 from += tmp;
737 bidx++;
738 } else if (bidx) {
739 bh = affs_bread_ino(inode, bidx - 1, 0);
740 if (IS_ERR(bh)) {
741 written = PTR_ERR(bh);
742 goto err_first_bh;
743 }
744 }
745 while (from + bsize <= to) {
746 prev_bh = bh;
747 bh = affs_getemptyblk_ino(inode, bidx);
748 if (IS_ERR(bh))
749 goto err_bh;
750 memcpy(AFFS_DATA(bh), data + from, bsize);
751 if (buffer_new(bh)) {
752 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
753 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
754 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx + 1);
755 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(bsize);
756 AFFS_DATA_HEAD(bh)->next = 0;
757 bh->b_state &= ~(1UL << BH_New);
758 if (prev_bh) {
759 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
760
761 if (tmp_next)
762 affs_warning(sb, "commit_write_ofs",
763 "next block already set for %d (%d)",
764 bidx, tmp_next);
765 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
766 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
767 mark_buffer_dirty_inode(prev_bh, inode);
768 }
769 }
770 affs_brelse(prev_bh);
771 affs_fix_checksum(sb, bh);
772 mark_buffer_dirty_inode(bh, inode);
773 written += bsize;
774 from += bsize;
775 bidx++;
776 }
777 if (from < to) {
778 prev_bh = bh;
779 bh = affs_bread_ino(inode, bidx, 1);
780 if (IS_ERR(bh))
781 goto err_bh;
782 tmp = min(bsize, to - from);
783 BUG_ON(tmp > bsize);
784 memcpy(AFFS_DATA(bh), data + from, tmp);
785 if (buffer_new(bh)) {
786 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
787 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
788 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx + 1);
789 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
790 AFFS_DATA_HEAD(bh)->next = 0;
791 bh->b_state &= ~(1UL << BH_New);
792 if (prev_bh) {
793 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
794
795 if (tmp_next)
796 affs_warning(sb, "commit_write_ofs",
797 "next block already set for %d (%d)",
798 bidx, tmp_next);
799 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
800 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
801 mark_buffer_dirty_inode(prev_bh, inode);
802 }
803 } else if (be32_to_cpu(AFFS_DATA_HEAD(bh)->size) < tmp)
804 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
805 affs_brelse(prev_bh);
806 affs_fix_checksum(sb, bh);
807 mark_buffer_dirty_inode(bh, inode);
808 written += tmp;
809 from += tmp;
810 bidx++;
811 }
812 folio_mark_uptodate(folio);
813
814 done:
815 affs_brelse(bh);
816 tmp = (folio->index << PAGE_SHIFT) + from;
817 if (tmp > inode->i_size)
818 inode->i_size = AFFS_I(inode)->mmu_private = tmp;
819
820 /* Clear Archived bit on file writes, as AmigaOS would do */
821 if (AFFS_I(inode)->i_protect & FIBF_ARCHIVED) {
822 AFFS_I(inode)->i_protect &= ~FIBF_ARCHIVED;
823 mark_inode_dirty(inode);
824 }
825
826 err_first_bh:
827 folio_unlock(folio);
828 folio_put(folio);
829
830 return written;
831
832 err_bh:
833 bh = prev_bh;
834 if (!written)
835 written = PTR_ERR(bh);
836 goto done;
837 }
838
839 const struct address_space_operations affs_aops_ofs = {
840 .dirty_folio = block_dirty_folio,
841 .invalidate_folio = block_invalidate_folio,
842 .read_folio = affs_read_folio_ofs,
843 //.writepages = affs_writepages_ofs,
844 .write_begin = affs_write_begin_ofs,
845 .write_end = affs_write_end_ofs,
846 .migrate_folio = filemap_migrate_folio,
847 };
848
849 /* Free any preallocated blocks. */
850
851 void
affs_free_prealloc(struct inode * inode)852 affs_free_prealloc(struct inode *inode)
853 {
854 struct super_block *sb = inode->i_sb;
855
856 pr_debug("free_prealloc(ino=%lu)\n", inode->i_ino);
857
858 while (AFFS_I(inode)->i_pa_cnt) {
859 AFFS_I(inode)->i_pa_cnt--;
860 affs_free_block(sb, ++AFFS_I(inode)->i_lastalloc);
861 }
862 }
863
864 /* Truncate (or enlarge) a file to the requested size. */
865
866 void
affs_truncate(struct inode * inode)867 affs_truncate(struct inode *inode)
868 {
869 struct super_block *sb = inode->i_sb;
870 u32 ext, ext_key;
871 u32 last_blk, blkcnt, blk;
872 u32 size;
873 struct buffer_head *ext_bh;
874 int i;
875
876 pr_debug("truncate(inode=%lu, oldsize=%llu, newsize=%llu)\n",
877 inode->i_ino, AFFS_I(inode)->mmu_private, inode->i_size);
878
879 last_blk = 0;
880 ext = 0;
881 if (inode->i_size) {
882 last_blk = ((u32)inode->i_size - 1) / AFFS_SB(sb)->s_data_blksize;
883 ext = last_blk / AFFS_SB(sb)->s_hashsize;
884 }
885
886 if (inode->i_size > AFFS_I(inode)->mmu_private) {
887 struct address_space *mapping = inode->i_mapping;
888 struct folio *folio;
889 void *fsdata = NULL;
890 loff_t isize = inode->i_size;
891 int res;
892
893 res = mapping->a_ops->write_begin(NULL, mapping, isize, 0, &folio, &fsdata);
894 if (!res)
895 res = mapping->a_ops->write_end(NULL, mapping, isize, 0, 0, folio, fsdata);
896 else
897 inode->i_size = AFFS_I(inode)->mmu_private;
898 mark_inode_dirty(inode);
899 return;
900 } else if (inode->i_size == AFFS_I(inode)->mmu_private)
901 return;
902
903 // lock cache
904 ext_bh = affs_get_extblock(inode, ext);
905 if (IS_ERR(ext_bh)) {
906 affs_warning(sb, "truncate",
907 "unexpected read error for ext block %u (%ld)",
908 ext, PTR_ERR(ext_bh));
909 return;
910 }
911 if (AFFS_I(inode)->i_lc) {
912 /* clear linear cache */
913 i = (ext + 1) >> AFFS_I(inode)->i_lc_shift;
914 if (AFFS_I(inode)->i_lc_size > i) {
915 AFFS_I(inode)->i_lc_size = i;
916 for (; i < AFFS_LC_SIZE; i++)
917 AFFS_I(inode)->i_lc[i] = 0;
918 }
919 /* clear associative cache */
920 for (i = 0; i < AFFS_AC_SIZE; i++)
921 if (AFFS_I(inode)->i_ac[i].ext >= ext)
922 AFFS_I(inode)->i_ac[i].ext = 0;
923 }
924 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
925
926 blkcnt = AFFS_I(inode)->i_blkcnt;
927 i = 0;
928 blk = last_blk;
929 if (inode->i_size) {
930 i = last_blk % AFFS_SB(sb)->s_hashsize + 1;
931 blk++;
932 } else
933 AFFS_HEAD(ext_bh)->first_data = 0;
934 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(i);
935 size = AFFS_SB(sb)->s_hashsize;
936 if (size > blkcnt - blk + i)
937 size = blkcnt - blk + i;
938 for (; i < size; i++, blk++) {
939 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
940 AFFS_BLOCK(sb, ext_bh, i) = 0;
941 }
942 AFFS_TAIL(sb, ext_bh)->extension = 0;
943 affs_fix_checksum(sb, ext_bh);
944 mark_buffer_dirty_inode(ext_bh, inode);
945 affs_brelse(ext_bh);
946
947 if (inode->i_size) {
948 AFFS_I(inode)->i_blkcnt = last_blk + 1;
949 AFFS_I(inode)->i_extcnt = ext + 1;
950 if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_OFS)) {
951 struct buffer_head *bh = affs_bread_ino(inode, last_blk, 0);
952 u32 tmp;
953 if (IS_ERR(bh)) {
954 affs_warning(sb, "truncate",
955 "unexpected read error for last block %u (%ld)",
956 ext, PTR_ERR(bh));
957 return;
958 }
959 tmp = be32_to_cpu(AFFS_DATA_HEAD(bh)->next);
960 AFFS_DATA_HEAD(bh)->next = 0;
961 affs_adjust_checksum(bh, -tmp);
962 affs_brelse(bh);
963 }
964 } else {
965 AFFS_I(inode)->i_blkcnt = 0;
966 AFFS_I(inode)->i_extcnt = 1;
967 }
968 AFFS_I(inode)->mmu_private = inode->i_size;
969 // unlock cache
970
971 while (ext_key) {
972 ext_bh = affs_bread(sb, ext_key);
973 size = AFFS_SB(sb)->s_hashsize;
974 if (size > blkcnt - blk)
975 size = blkcnt - blk;
976 for (i = 0; i < size; i++, blk++)
977 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
978 affs_free_block(sb, ext_key);
979 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
980 affs_brelse(ext_bh);
981 }
982 affs_free_prealloc(inode);
983 }
984
affs_file_fsync(struct file * filp,loff_t start,loff_t end,int datasync)985 int affs_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
986 {
987 struct inode *inode = filp->f_mapping->host;
988 int ret, err;
989
990 err = file_write_and_wait_range(filp, start, end);
991 if (err)
992 return err;
993
994 inode_lock(inode);
995 ret = write_inode_now(inode, 0);
996 err = sync_blockdev(inode->i_sb->s_bdev);
997 if (!ret)
998 ret = err;
999 inode_unlock(inode);
1000 return ret;
1001 }
1002 const struct file_operations affs_file_operations = {
1003 .llseek = generic_file_llseek,
1004 .read_iter = generic_file_read_iter,
1005 .write_iter = generic_file_write_iter,
1006 .mmap_prepare = generic_file_mmap_prepare,
1007 .open = affs_file_open,
1008 .release = affs_file_release,
1009 .fsync = affs_file_fsync,
1010 .splice_read = filemap_splice_read,
1011 };
1012
1013 const struct inode_operations affs_file_inode_operations = {
1014 .setattr = affs_notify_change,
1015 };
1016