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/filelock.h>
19 #include <linux/mpage.h>
20 #include "affs.h"
21
22 static struct buffer_head *affs_get_extblock_slow(struct inode *inode, u32 ext);
23
24 static int
affs_file_open(struct inode * inode,struct file * filp)25 affs_file_open(struct inode *inode, struct file *filp)
26 {
27 pr_debug("open(%lu,%d)\n",
28 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
29 atomic_inc(&AFFS_I(inode)->i_opencnt);
30 return 0;
31 }
32
33 static int
affs_file_release(struct inode * inode,struct file * filp)34 affs_file_release(struct inode *inode, struct file *filp)
35 {
36 pr_debug("release(%lu, %d)\n",
37 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
38
39 if (atomic_dec_and_test(&AFFS_I(inode)->i_opencnt)) {
40 inode_lock(inode);
41 if (inode->i_size != AFFS_I(inode)->mmu_private)
42 affs_truncate(inode);
43 affs_free_prealloc(inode);
44 inode_unlock(inode);
45 }
46
47 return 0;
48 }
49
50 static int
affs_grow_extcache(struct inode * inode,u32 lc_idx)51 affs_grow_extcache(struct inode *inode, u32 lc_idx)
52 {
53 struct super_block *sb = inode->i_sb;
54 struct buffer_head *bh;
55 u32 lc_max;
56 int i, j, key;
57
58 if (!AFFS_I(inode)->i_lc) {
59 char *ptr = (char *)get_zeroed_page(GFP_NOFS);
60 if (!ptr)
61 return -ENOMEM;
62 AFFS_I(inode)->i_lc = (u32 *)ptr;
63 AFFS_I(inode)->i_ac = (struct affs_ext_key *)(ptr + AFFS_CACHE_SIZE / 2);
64 }
65
66 lc_max = AFFS_LC_SIZE << AFFS_I(inode)->i_lc_shift;
67
68 if (AFFS_I(inode)->i_extcnt > lc_max) {
69 u32 lc_shift, lc_mask, tmp, off;
70
71 /* need to recalculate linear cache, start from old size */
72 lc_shift = AFFS_I(inode)->i_lc_shift;
73 tmp = (AFFS_I(inode)->i_extcnt / AFFS_LC_SIZE) >> lc_shift;
74 for (; tmp; tmp >>= 1)
75 lc_shift++;
76 lc_mask = (1 << lc_shift) - 1;
77
78 /* fix idx and old size to new shift */
79 lc_idx >>= (lc_shift - AFFS_I(inode)->i_lc_shift);
80 AFFS_I(inode)->i_lc_size >>= (lc_shift - AFFS_I(inode)->i_lc_shift);
81
82 /* first shrink old cache to make more space */
83 off = 1 << (lc_shift - AFFS_I(inode)->i_lc_shift);
84 for (i = 1, j = off; j < AFFS_LC_SIZE; i++, j += off)
85 AFFS_I(inode)->i_ac[i] = AFFS_I(inode)->i_ac[j];
86
87 AFFS_I(inode)->i_lc_shift = lc_shift;
88 AFFS_I(inode)->i_lc_mask = lc_mask;
89 }
90
91 /* fill cache to the needed index */
92 i = AFFS_I(inode)->i_lc_size;
93 AFFS_I(inode)->i_lc_size = lc_idx + 1;
94 for (; i <= lc_idx; i++) {
95 if (!i) {
96 AFFS_I(inode)->i_lc[0] = inode->i_ino;
97 continue;
98 }
99 key = AFFS_I(inode)->i_lc[i - 1];
100 j = AFFS_I(inode)->i_lc_mask + 1;
101 // unlock cache
102 for (; j > 0; j--) {
103 bh = affs_bread(sb, key);
104 if (!bh)
105 goto err;
106 key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
107 affs_brelse(bh);
108 }
109 // lock cache
110 AFFS_I(inode)->i_lc[i] = key;
111 }
112
113 return 0;
114
115 err:
116 // lock cache
117 return -EIO;
118 }
119
120 static struct buffer_head *
affs_alloc_extblock(struct inode * inode,struct buffer_head * bh,u32 ext)121 affs_alloc_extblock(struct inode *inode, struct buffer_head *bh, u32 ext)
122 {
123 struct super_block *sb = inode->i_sb;
124 struct buffer_head *new_bh;
125 u32 blocknr, tmp;
126
127 blocknr = affs_alloc_block(inode, bh->b_blocknr);
128 if (!blocknr)
129 return ERR_PTR(-ENOSPC);
130
131 new_bh = affs_getzeroblk(sb, blocknr);
132 if (!new_bh) {
133 affs_free_block(sb, blocknr);
134 return ERR_PTR(-EIO);
135 }
136
137 AFFS_HEAD(new_bh)->ptype = cpu_to_be32(T_LIST);
138 AFFS_HEAD(new_bh)->key = cpu_to_be32(blocknr);
139 AFFS_TAIL(sb, new_bh)->stype = cpu_to_be32(ST_FILE);
140 AFFS_TAIL(sb, new_bh)->parent = cpu_to_be32(inode->i_ino);
141 affs_fix_checksum(sb, new_bh);
142
143 mark_buffer_dirty_inode(new_bh, inode);
144
145 tmp = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
146 if (tmp)
147 affs_warning(sb, "alloc_ext", "previous extension set (%x)", tmp);
148 AFFS_TAIL(sb, bh)->extension = cpu_to_be32(blocknr);
149 affs_adjust_checksum(bh, blocknr - tmp);
150 mark_buffer_dirty_inode(bh, inode);
151
152 AFFS_I(inode)->i_extcnt++;
153 mark_inode_dirty(inode);
154
155 return new_bh;
156 }
157
158 static inline struct buffer_head *
affs_get_extblock(struct inode * inode,u32 ext)159 affs_get_extblock(struct inode *inode, u32 ext)
160 {
161 /* inline the simplest case: same extended block as last time */
162 struct buffer_head *bh = AFFS_I(inode)->i_ext_bh;
163 if (ext == AFFS_I(inode)->i_ext_last)
164 get_bh(bh);
165 else
166 /* we have to do more (not inlined) */
167 bh = affs_get_extblock_slow(inode, ext);
168
169 return bh;
170 }
171
172 static struct buffer_head *
affs_get_extblock_slow(struct inode * inode,u32 ext)173 affs_get_extblock_slow(struct inode *inode, u32 ext)
174 {
175 struct super_block *sb = inode->i_sb;
176 struct buffer_head *bh;
177 u32 ext_key;
178 u32 lc_idx, lc_off, ac_idx;
179 u32 tmp, idx;
180
181 if (ext == AFFS_I(inode)->i_ext_last + 1) {
182 /* read the next extended block from the current one */
183 bh = AFFS_I(inode)->i_ext_bh;
184 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
185 if (ext < AFFS_I(inode)->i_extcnt)
186 goto read_ext;
187 BUG_ON(ext > AFFS_I(inode)->i_extcnt);
188 bh = affs_alloc_extblock(inode, bh, ext);
189 if (IS_ERR(bh))
190 return bh;
191 goto store_ext;
192 }
193
194 if (ext == 0) {
195 /* we seek back to the file header block */
196 ext_key = inode->i_ino;
197 goto read_ext;
198 }
199
200 if (ext >= AFFS_I(inode)->i_extcnt) {
201 struct buffer_head *prev_bh;
202
203 /* allocate a new extended block */
204 BUG_ON(ext > AFFS_I(inode)->i_extcnt);
205
206 /* get previous extended block */
207 prev_bh = affs_get_extblock(inode, ext - 1);
208 if (IS_ERR(prev_bh))
209 return prev_bh;
210 bh = affs_alloc_extblock(inode, prev_bh, ext);
211 affs_brelse(prev_bh);
212 if (IS_ERR(bh))
213 return bh;
214 goto store_ext;
215 }
216
217 again:
218 /* check if there is an extended cache and whether it's large enough */
219 lc_idx = ext >> AFFS_I(inode)->i_lc_shift;
220 lc_off = ext & AFFS_I(inode)->i_lc_mask;
221
222 if (lc_idx >= AFFS_I(inode)->i_lc_size) {
223 int err;
224
225 err = affs_grow_extcache(inode, lc_idx);
226 if (err)
227 return ERR_PTR(err);
228 goto again;
229 }
230
231 /* every n'th key we find in the linear cache */
232 if (!lc_off) {
233 ext_key = AFFS_I(inode)->i_lc[lc_idx];
234 goto read_ext;
235 }
236
237 /* maybe it's still in the associative cache */
238 ac_idx = (ext - lc_idx - 1) & AFFS_AC_MASK;
239 if (AFFS_I(inode)->i_ac[ac_idx].ext == ext) {
240 ext_key = AFFS_I(inode)->i_ac[ac_idx].key;
241 goto read_ext;
242 }
243
244 /* try to find one of the previous extended blocks */
245 tmp = ext;
246 idx = ac_idx;
247 while (--tmp, --lc_off > 0) {
248 idx = (idx - 1) & AFFS_AC_MASK;
249 if (AFFS_I(inode)->i_ac[idx].ext == tmp) {
250 ext_key = AFFS_I(inode)->i_ac[idx].key;
251 goto find_ext;
252 }
253 }
254
255 /* fall back to the linear cache */
256 ext_key = AFFS_I(inode)->i_lc[lc_idx];
257 find_ext:
258 /* read all extended blocks until we find the one we need */
259 //unlock cache
260 do {
261 bh = affs_bread(sb, ext_key);
262 if (!bh)
263 goto err_bread;
264 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
265 affs_brelse(bh);
266 tmp++;
267 } while (tmp < ext);
268 //lock cache
269
270 /* store it in the associative cache */
271 // recalculate ac_idx?
272 AFFS_I(inode)->i_ac[ac_idx].ext = ext;
273 AFFS_I(inode)->i_ac[ac_idx].key = ext_key;
274
275 read_ext:
276 /* finally read the right extended block */
277 //unlock cache
278 bh = affs_bread(sb, ext_key);
279 if (!bh)
280 goto err_bread;
281 //lock cache
282
283 store_ext:
284 /* release old cached extended block and store the new one */
285 affs_brelse(AFFS_I(inode)->i_ext_bh);
286 AFFS_I(inode)->i_ext_last = ext;
287 AFFS_I(inode)->i_ext_bh = bh;
288 get_bh(bh);
289
290 return bh;
291
292 err_bread:
293 affs_brelse(bh);
294 return ERR_PTR(-EIO);
295 }
296
297 static int
affs_get_block(struct inode * inode,sector_t block,struct buffer_head * bh_result,int create)298 affs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh_result, int create)
299 {
300 struct super_block *sb = inode->i_sb;
301 struct buffer_head *ext_bh;
302 u32 ext;
303
304 pr_debug("%s(%lu, %llu)\n", __func__, inode->i_ino,
305 (unsigned long long)block);
306
307 BUG_ON(block > (sector_t)0x7fffffffUL);
308
309 if (block >= AFFS_I(inode)->i_blkcnt) {
310 if (block > AFFS_I(inode)->i_blkcnt || !create)
311 goto err_big;
312 } else
313 create = 0;
314
315 //lock cache
316 affs_lock_ext(inode);
317
318 ext = (u32)block / AFFS_SB(sb)->s_hashsize;
319 block -= ext * AFFS_SB(sb)->s_hashsize;
320 ext_bh = affs_get_extblock(inode, ext);
321 if (IS_ERR(ext_bh))
322 goto err_ext;
323 map_bh(bh_result, sb, (sector_t)be32_to_cpu(AFFS_BLOCK(sb, ext_bh, block)));
324
325 if (create) {
326 u32 blocknr = affs_alloc_block(inode, ext_bh->b_blocknr);
327 if (!blocknr)
328 goto err_alloc;
329 set_buffer_new(bh_result);
330 AFFS_I(inode)->mmu_private += AFFS_SB(sb)->s_data_blksize;
331 AFFS_I(inode)->i_blkcnt++;
332
333 /* store new block */
334 if (bh_result->b_blocknr)
335 affs_warning(sb, "get_block",
336 "block already set (%llx)",
337 (unsigned long long)bh_result->b_blocknr);
338 AFFS_BLOCK(sb, ext_bh, block) = cpu_to_be32(blocknr);
339 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(block + 1);
340 affs_adjust_checksum(ext_bh, blocknr - bh_result->b_blocknr + 1);
341 bh_result->b_blocknr = blocknr;
342
343 if (!block) {
344 /* insert first block into header block */
345 u32 tmp = be32_to_cpu(AFFS_HEAD(ext_bh)->first_data);
346 if (tmp)
347 affs_warning(sb, "get_block", "first block already set (%d)", tmp);
348 AFFS_HEAD(ext_bh)->first_data = cpu_to_be32(blocknr);
349 affs_adjust_checksum(ext_bh, blocknr - tmp);
350 }
351 }
352
353 affs_brelse(ext_bh);
354 //unlock cache
355 affs_unlock_ext(inode);
356 return 0;
357
358 err_big:
359 affs_error(inode->i_sb, "get_block", "strange block request %llu",
360 (unsigned long long)block);
361 return -EIO;
362 err_ext:
363 // unlock cache
364 affs_unlock_ext(inode);
365 return PTR_ERR(ext_bh);
366 err_alloc:
367 brelse(ext_bh);
368 clear_buffer_mapped(bh_result);
369 bh_result->b_bdev = NULL;
370 // unlock cache
371 affs_unlock_ext(inode);
372 return -ENOSPC;
373 }
374
affs_writepages(struct address_space * mapping,struct writeback_control * wbc)375 static int affs_writepages(struct address_space *mapping,
376 struct writeback_control *wbc)
377 {
378 return mpage_writepages(mapping, wbc, affs_get_block);
379 }
380
affs_read_folio(struct file * file,struct folio * folio)381 static int affs_read_folio(struct file *file, struct folio *folio)
382 {
383 return block_read_full_folio(folio, affs_get_block);
384 }
385
affs_write_failed(struct address_space * mapping,loff_t to)386 static void affs_write_failed(struct address_space *mapping, loff_t to)
387 {
388 struct inode *inode = mapping->host;
389
390 if (to > inode->i_size) {
391 truncate_pagecache(inode, inode->i_size);
392 affs_truncate(inode);
393 }
394 }
395
396 static ssize_t
affs_direct_IO(struct kiocb * iocb,struct iov_iter * iter)397 affs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
398 {
399 struct file *file = iocb->ki_filp;
400 struct address_space *mapping = file->f_mapping;
401 struct inode *inode = mapping->host;
402 size_t count = iov_iter_count(iter);
403 loff_t offset = iocb->ki_pos;
404 ssize_t ret;
405
406 if (iov_iter_rw(iter) == WRITE) {
407 loff_t size = offset + count;
408
409 if (AFFS_I(inode)->mmu_private < size)
410 return 0;
411 }
412
413 ret = blockdev_direct_IO(iocb, inode, iter, affs_get_block);
414 if (ret < 0 && iov_iter_rw(iter) == WRITE)
415 affs_write_failed(mapping, offset + count);
416 return ret;
417 }
418
affs_write_begin(const struct kiocb * iocb,struct address_space * mapping,loff_t pos,unsigned len,struct folio ** foliop,void ** fsdata)419 static int affs_write_begin(const struct kiocb *iocb,
420 struct address_space *mapping,
421 loff_t pos, unsigned len,
422 struct folio **foliop, void **fsdata)
423 {
424 int ret;
425
426 ret = cont_write_begin(iocb, mapping, pos, len, foliop, fsdata,
427 affs_get_block,
428 &AFFS_I(mapping->host)->mmu_private);
429 if (unlikely(ret))
430 affs_write_failed(mapping, pos + len);
431
432 return ret;
433 }
434
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)435 static int affs_write_end(const struct kiocb *iocb,
436 struct address_space *mapping, loff_t pos,
437 unsigned int len, unsigned int copied,
438 struct folio *folio, void *fsdata)
439 {
440 struct inode *inode = mapping->host;
441 int ret;
442
443 ret = generic_write_end(iocb, mapping, pos, len, copied, folio, fsdata);
444
445 /* Clear Archived bit on file writes, as AmigaOS would do */
446 if (AFFS_I(inode)->i_protect & FIBF_ARCHIVED) {
447 AFFS_I(inode)->i_protect &= ~FIBF_ARCHIVED;
448 mark_inode_dirty(inode);
449 }
450
451 return ret;
452 }
453
_affs_bmap(struct address_space * mapping,sector_t block)454 static sector_t _affs_bmap(struct address_space *mapping, sector_t block)
455 {
456 return generic_block_bmap(mapping,block,affs_get_block);
457 }
458
459 const struct address_space_operations affs_aops = {
460 .dirty_folio = block_dirty_folio,
461 .invalidate_folio = block_invalidate_folio,
462 .read_folio = affs_read_folio,
463 .writepages = affs_writepages,
464 .write_begin = affs_write_begin,
465 .write_end = affs_write_end,
466 .direct_IO = affs_direct_IO,
467 .migrate_folio = buffer_migrate_folio,
468 .bmap = _affs_bmap
469 };
470
471 static inline struct buffer_head *
affs_bread_ino(struct inode * inode,int block,int create)472 affs_bread_ino(struct inode *inode, int block, int create)
473 {
474 struct buffer_head *bh, tmp_bh;
475 int err;
476
477 tmp_bh.b_state = 0;
478 err = affs_get_block(inode, block, &tmp_bh, create);
479 if (!err) {
480 bh = affs_bread(inode->i_sb, tmp_bh.b_blocknr);
481 if (bh) {
482 bh->b_state |= tmp_bh.b_state;
483 return bh;
484 }
485 err = -EIO;
486 }
487 return ERR_PTR(err);
488 }
489
490 static inline struct buffer_head *
affs_getzeroblk_ino(struct inode * inode,int block)491 affs_getzeroblk_ino(struct inode *inode, int block)
492 {
493 struct buffer_head *bh, tmp_bh;
494 int err;
495
496 tmp_bh.b_state = 0;
497 err = affs_get_block(inode, block, &tmp_bh, 1);
498 if (!err) {
499 bh = affs_getzeroblk(inode->i_sb, tmp_bh.b_blocknr);
500 if (bh) {
501 bh->b_state |= tmp_bh.b_state;
502 return bh;
503 }
504 err = -EIO;
505 }
506 return ERR_PTR(err);
507 }
508
509 static inline struct buffer_head *
affs_getemptyblk_ino(struct inode * inode,int block)510 affs_getemptyblk_ino(struct inode *inode, int block)
511 {
512 struct buffer_head *bh, tmp_bh;
513 int err;
514
515 tmp_bh.b_state = 0;
516 err = affs_get_block(inode, block, &tmp_bh, 1);
517 if (!err) {
518 bh = affs_getemptyblk(inode->i_sb, tmp_bh.b_blocknr);
519 if (bh) {
520 bh->b_state |= tmp_bh.b_state;
521 return bh;
522 }
523 err = -EIO;
524 }
525 return ERR_PTR(err);
526 }
527
affs_do_read_folio_ofs(struct folio * folio,size_t to,int create)528 static int affs_do_read_folio_ofs(struct folio *folio, size_t to, int create)
529 {
530 struct inode *inode = folio->mapping->host;
531 struct super_block *sb = inode->i_sb;
532 struct buffer_head *bh;
533 size_t pos = 0;
534 size_t bidx, boff, bsize;
535 u32 tmp;
536
537 pr_debug("%s(%lu, %ld, 0, %zu)\n", __func__, inode->i_ino,
538 folio->index, to);
539 BUG_ON(to > folio_size(folio));
540 bsize = AFFS_SB(sb)->s_data_blksize;
541 tmp = folio_pos(folio);
542 bidx = tmp / bsize;
543 boff = tmp % bsize;
544
545 while (pos < to) {
546 bh = affs_bread_ino(inode, bidx, create);
547 if (IS_ERR(bh))
548 return PTR_ERR(bh);
549 tmp = min(bsize - boff, to - pos);
550 BUG_ON(pos + tmp > to || tmp > bsize);
551 memcpy_to_folio(folio, pos, AFFS_DATA(bh) + boff, tmp);
552 affs_brelse(bh);
553 bidx++;
554 pos += tmp;
555 boff = 0;
556 }
557 return 0;
558 }
559
560 static int
affs_extent_file_ofs(struct inode * inode,u32 newsize)561 affs_extent_file_ofs(struct inode *inode, u32 newsize)
562 {
563 struct super_block *sb = inode->i_sb;
564 struct buffer_head *bh, *prev_bh;
565 u32 bidx, boff;
566 u32 size, bsize;
567 u32 tmp;
568
569 pr_debug("%s(%lu, %d)\n", __func__, inode->i_ino, newsize);
570 bsize = AFFS_SB(sb)->s_data_blksize;
571 bh = NULL;
572 size = AFFS_I(inode)->mmu_private;
573 bidx = size / bsize;
574 boff = size % bsize;
575 if (boff) {
576 bh = affs_bread_ino(inode, bidx, 0);
577 if (IS_ERR(bh))
578 return PTR_ERR(bh);
579 tmp = min(bsize - boff, newsize - size);
580 BUG_ON(boff + tmp > bsize || tmp > bsize);
581 memset(AFFS_DATA(bh) + boff, 0, tmp);
582 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp);
583 affs_fix_checksum(sb, bh);
584 mark_buffer_dirty_inode(bh, inode);
585 size += tmp;
586 bidx++;
587 } else if (bidx) {
588 bh = affs_bread_ino(inode, bidx - 1, 0);
589 if (IS_ERR(bh))
590 return PTR_ERR(bh);
591 }
592
593 while (size < newsize) {
594 prev_bh = bh;
595 bh = affs_getzeroblk_ino(inode, bidx);
596 if (IS_ERR(bh))
597 goto out;
598 tmp = min(bsize, newsize - size);
599 BUG_ON(tmp > bsize);
600 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
601 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
602 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx + 1);
603 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
604 affs_fix_checksum(sb, bh);
605 bh->b_state &= ~(1UL << BH_New);
606 mark_buffer_dirty_inode(bh, inode);
607 if (prev_bh) {
608 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
609
610 if (tmp_next)
611 affs_warning(sb, "extent_file_ofs",
612 "next block already set for %d (%d)",
613 bidx, tmp_next);
614 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
615 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
616 mark_buffer_dirty_inode(prev_bh, inode);
617 affs_brelse(prev_bh);
618 }
619 size += bsize;
620 bidx++;
621 }
622 affs_brelse(bh);
623 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
624 return 0;
625
626 out:
627 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
628 return PTR_ERR(bh);
629 }
630
affs_read_folio_ofs(struct file * file,struct folio * folio)631 static int affs_read_folio_ofs(struct file *file, struct folio *folio)
632 {
633 struct inode *inode = folio->mapping->host;
634 size_t to;
635 int err;
636
637 pr_debug("%s(%lu, %ld)\n", __func__, inode->i_ino, folio->index);
638 to = folio_size(folio);
639 if (folio_pos(folio) + to > inode->i_size) {
640 to = inode->i_size - folio_pos(folio);
641 folio_zero_segment(folio, to, folio_size(folio));
642 }
643
644 err = affs_do_read_folio_ofs(folio, to, 0);
645 if (!err)
646 folio_mark_uptodate(folio);
647 folio_unlock(folio);
648 return err;
649 }
650
affs_write_begin_ofs(const struct kiocb * iocb,struct address_space * mapping,loff_t pos,unsigned len,struct folio ** foliop,void ** fsdata)651 static int affs_write_begin_ofs(const struct kiocb *iocb,
652 struct address_space *mapping,
653 loff_t pos, unsigned len,
654 struct folio **foliop, void **fsdata)
655 {
656 struct inode *inode = mapping->host;
657 struct folio *folio;
658 pgoff_t index;
659 int err = 0;
660
661 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos,
662 pos + len);
663 if (pos > AFFS_I(inode)->mmu_private) {
664 /* XXX: this probably leaves a too-big i_size in case of
665 * failure. Should really be updating i_size at write_end time
666 */
667 err = affs_extent_file_ofs(inode, pos);
668 if (err)
669 return err;
670 }
671
672 index = pos >> PAGE_SHIFT;
673 folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN,
674 mapping_gfp_mask(mapping));
675 if (IS_ERR(folio))
676 return PTR_ERR(folio);
677 *foliop = folio;
678
679 if (folio_test_uptodate(folio))
680 return 0;
681
682 /* XXX: inefficient but safe in the face of short writes */
683 err = affs_do_read_folio_ofs(folio, folio_size(folio), 1);
684 if (err) {
685 folio_unlock(folio);
686 folio_put(folio);
687 }
688 return err;
689 }
690
affs_write_end_ofs(const struct kiocb * iocb,struct address_space * mapping,loff_t pos,unsigned len,unsigned copied,struct folio * folio,void * fsdata)691 static int affs_write_end_ofs(const struct kiocb *iocb,
692 struct address_space *mapping,
693 loff_t pos, unsigned len, unsigned copied,
694 struct folio *folio, void *fsdata)
695 {
696 struct inode *inode = mapping->host;
697 struct super_block *sb = inode->i_sb;
698 struct buffer_head *bh, *prev_bh;
699 char *data;
700 u32 bidx, boff, bsize;
701 unsigned from, to;
702 u32 tmp;
703 int written;
704
705 from = pos & (PAGE_SIZE - 1);
706 to = from + len;
707 /*
708 * XXX: not sure if this can handle short copies (len < copied), but
709 * we don't have to, because the folio should always be uptodate here,
710 * due to write_begin.
711 */
712
713 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos,
714 pos + len);
715 bsize = AFFS_SB(sb)->s_data_blksize;
716 data = folio_address(folio);
717
718 bh = NULL;
719 written = 0;
720 tmp = (folio->index << PAGE_SHIFT) + from;
721 bidx = tmp / bsize;
722 boff = tmp % bsize;
723 if (boff) {
724 bh = affs_bread_ino(inode, bidx, 0);
725 if (IS_ERR(bh)) {
726 written = PTR_ERR(bh);
727 goto err_first_bh;
728 }
729 tmp = min(bsize - boff, to - from);
730 BUG_ON(boff + tmp > bsize || tmp > bsize);
731 memcpy(AFFS_DATA(bh) + boff, data + from, tmp);
732 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(
733 max(boff + tmp, be32_to_cpu(AFFS_DATA_HEAD(bh)->size)));
734 affs_fix_checksum(sb, bh);
735 mark_buffer_dirty_inode(bh, inode);
736 written += tmp;
737 from += tmp;
738 bidx++;
739 } else if (bidx) {
740 bh = affs_bread_ino(inode, bidx - 1, 0);
741 if (IS_ERR(bh)) {
742 written = PTR_ERR(bh);
743 goto err_first_bh;
744 }
745 }
746 while (from + bsize <= to) {
747 prev_bh = bh;
748 bh = affs_getemptyblk_ino(inode, bidx);
749 if (IS_ERR(bh))
750 goto err_bh;
751 memcpy(AFFS_DATA(bh), data + from, bsize);
752 if (buffer_new(bh)) {
753 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
754 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
755 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx + 1);
756 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(bsize);
757 AFFS_DATA_HEAD(bh)->next = 0;
758 bh->b_state &= ~(1UL << BH_New);
759 if (prev_bh) {
760 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
761
762 if (tmp_next)
763 affs_warning(sb, "commit_write_ofs",
764 "next block already set for %d (%d)",
765 bidx, tmp_next);
766 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
767 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
768 mark_buffer_dirty_inode(prev_bh, inode);
769 }
770 }
771 affs_brelse(prev_bh);
772 affs_fix_checksum(sb, bh);
773 mark_buffer_dirty_inode(bh, inode);
774 written += bsize;
775 from += bsize;
776 bidx++;
777 }
778 if (from < to) {
779 prev_bh = bh;
780 bh = affs_bread_ino(inode, bidx, 1);
781 if (IS_ERR(bh))
782 goto err_bh;
783 tmp = min(bsize, to - from);
784 BUG_ON(tmp > bsize);
785 memcpy(AFFS_DATA(bh), data + from, tmp);
786 if (buffer_new(bh)) {
787 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
788 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
789 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx + 1);
790 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
791 AFFS_DATA_HEAD(bh)->next = 0;
792 bh->b_state &= ~(1UL << BH_New);
793 if (prev_bh) {
794 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
795
796 if (tmp_next)
797 affs_warning(sb, "commit_write_ofs",
798 "next block already set for %d (%d)",
799 bidx, tmp_next);
800 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
801 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
802 mark_buffer_dirty_inode(prev_bh, inode);
803 }
804 } else if (be32_to_cpu(AFFS_DATA_HEAD(bh)->size) < tmp)
805 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
806 affs_brelse(prev_bh);
807 affs_fix_checksum(sb, bh);
808 mark_buffer_dirty_inode(bh, inode);
809 written += tmp;
810 from += tmp;
811 bidx++;
812 }
813 folio_mark_uptodate(folio);
814
815 done:
816 affs_brelse(bh);
817 tmp = (folio->index << PAGE_SHIFT) + from;
818 if (tmp > inode->i_size)
819 inode->i_size = AFFS_I(inode)->mmu_private = tmp;
820
821 /* Clear Archived bit on file writes, as AmigaOS would do */
822 if (AFFS_I(inode)->i_protect & FIBF_ARCHIVED) {
823 AFFS_I(inode)->i_protect &= ~FIBF_ARCHIVED;
824 mark_inode_dirty(inode);
825 }
826
827 err_first_bh:
828 folio_unlock(folio);
829 folio_put(folio);
830
831 return written;
832
833 err_bh:
834 bh = prev_bh;
835 if (!written)
836 written = PTR_ERR(bh);
837 goto done;
838 }
839
840 const struct address_space_operations affs_aops_ofs = {
841 .dirty_folio = block_dirty_folio,
842 .invalidate_folio = block_invalidate_folio,
843 .read_folio = affs_read_folio_ofs,
844 //.writepages = affs_writepages_ofs,
845 .write_begin = affs_write_begin_ofs,
846 .write_end = affs_write_end_ofs,
847 .migrate_folio = filemap_migrate_folio,
848 };
849
850 /* Free any preallocated blocks. */
851
852 void
affs_free_prealloc(struct inode * inode)853 affs_free_prealloc(struct inode *inode)
854 {
855 struct super_block *sb = inode->i_sb;
856
857 pr_debug("free_prealloc(ino=%lu)\n", inode->i_ino);
858
859 while (AFFS_I(inode)->i_pa_cnt) {
860 AFFS_I(inode)->i_pa_cnt--;
861 affs_free_block(sb, ++AFFS_I(inode)->i_lastalloc);
862 }
863 }
864
865 /* Truncate (or enlarge) a file to the requested size. */
866
867 void
affs_truncate(struct inode * inode)868 affs_truncate(struct inode *inode)
869 {
870 struct super_block *sb = inode->i_sb;
871 u32 ext, ext_key;
872 u32 last_blk, blkcnt, blk;
873 u32 size;
874 struct buffer_head *ext_bh;
875 int i;
876
877 pr_debug("truncate(inode=%lu, oldsize=%llu, newsize=%llu)\n",
878 inode->i_ino, AFFS_I(inode)->mmu_private, inode->i_size);
879
880 last_blk = 0;
881 ext = 0;
882 if (inode->i_size) {
883 last_blk = ((u32)inode->i_size - 1) / AFFS_SB(sb)->s_data_blksize;
884 ext = last_blk / AFFS_SB(sb)->s_hashsize;
885 }
886
887 if (inode->i_size > AFFS_I(inode)->mmu_private) {
888 struct address_space *mapping = inode->i_mapping;
889 struct folio *folio;
890 void *fsdata = NULL;
891 loff_t isize = inode->i_size;
892 int res;
893
894 res = mapping->a_ops->write_begin(NULL, mapping, isize, 0, &folio, &fsdata);
895 if (!res)
896 res = mapping->a_ops->write_end(NULL, mapping, isize, 0, 0, folio, fsdata);
897 else
898 inode->i_size = AFFS_I(inode)->mmu_private;
899 mark_inode_dirty(inode);
900 return;
901 } else if (inode->i_size == AFFS_I(inode)->mmu_private)
902 return;
903
904 // lock cache
905 ext_bh = affs_get_extblock(inode, ext);
906 if (IS_ERR(ext_bh)) {
907 affs_warning(sb, "truncate",
908 "unexpected read error for ext block %u (%ld)",
909 ext, PTR_ERR(ext_bh));
910 return;
911 }
912 if (AFFS_I(inode)->i_lc) {
913 /* clear linear cache */
914 i = (ext + 1) >> AFFS_I(inode)->i_lc_shift;
915 if (AFFS_I(inode)->i_lc_size > i) {
916 AFFS_I(inode)->i_lc_size = i;
917 for (; i < AFFS_LC_SIZE; i++)
918 AFFS_I(inode)->i_lc[i] = 0;
919 }
920 /* clear associative cache */
921 for (i = 0; i < AFFS_AC_SIZE; i++)
922 if (AFFS_I(inode)->i_ac[i].ext >= ext)
923 AFFS_I(inode)->i_ac[i].ext = 0;
924 }
925 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
926
927 blkcnt = AFFS_I(inode)->i_blkcnt;
928 i = 0;
929 blk = last_blk;
930 if (inode->i_size) {
931 i = last_blk % AFFS_SB(sb)->s_hashsize + 1;
932 blk++;
933 } else
934 AFFS_HEAD(ext_bh)->first_data = 0;
935 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(i);
936 size = AFFS_SB(sb)->s_hashsize;
937 if (size > blkcnt - blk + i)
938 size = blkcnt - blk + i;
939 for (; i < size; i++, blk++) {
940 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
941 AFFS_BLOCK(sb, ext_bh, i) = 0;
942 }
943 AFFS_TAIL(sb, ext_bh)->extension = 0;
944 affs_fix_checksum(sb, ext_bh);
945 mark_buffer_dirty_inode(ext_bh, inode);
946 affs_brelse(ext_bh);
947
948 if (inode->i_size) {
949 AFFS_I(inode)->i_blkcnt = last_blk + 1;
950 AFFS_I(inode)->i_extcnt = ext + 1;
951 if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_OFS)) {
952 struct buffer_head *bh = affs_bread_ino(inode, last_blk, 0);
953 u32 tmp;
954 if (IS_ERR(bh)) {
955 affs_warning(sb, "truncate",
956 "unexpected read error for last block %u (%ld)",
957 ext, PTR_ERR(bh));
958 return;
959 }
960 tmp = be32_to_cpu(AFFS_DATA_HEAD(bh)->next);
961 AFFS_DATA_HEAD(bh)->next = 0;
962 affs_adjust_checksum(bh, -tmp);
963 affs_brelse(bh);
964 }
965 } else {
966 AFFS_I(inode)->i_blkcnt = 0;
967 AFFS_I(inode)->i_extcnt = 1;
968 }
969 AFFS_I(inode)->mmu_private = inode->i_size;
970 // unlock cache
971
972 while (ext_key) {
973 ext_bh = affs_bread(sb, ext_key);
974 size = AFFS_SB(sb)->s_hashsize;
975 if (size > blkcnt - blk)
976 size = blkcnt - blk;
977 for (i = 0; i < size; i++, blk++)
978 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
979 affs_free_block(sb, ext_key);
980 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
981 affs_brelse(ext_bh);
982 }
983 affs_free_prealloc(inode);
984 }
985
affs_file_fsync(struct file * filp,loff_t start,loff_t end,int datasync)986 int affs_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
987 {
988 struct inode *inode = filp->f_mapping->host;
989 int ret, err;
990
991 err = file_write_and_wait_range(filp, start, end);
992 if (err)
993 return err;
994
995 inode_lock(inode);
996 ret = write_inode_now(inode, 0);
997 err = sync_blockdev(inode->i_sb->s_bdev);
998 if (!ret)
999 ret = err;
1000 inode_unlock(inode);
1001 return ret;
1002 }
1003 const struct file_operations affs_file_operations = {
1004 .llseek = generic_file_llseek,
1005 .read_iter = generic_file_read_iter,
1006 .write_iter = generic_file_write_iter,
1007 .mmap_prepare = generic_file_mmap_prepare,
1008 .open = affs_file_open,
1009 .release = affs_file_release,
1010 .fsync = affs_file_fsync,
1011 .splice_read = filemap_splice_read,
1012 .setlease = generic_setlease,
1013 };
1014
1015 const struct inode_operations affs_file_inode_operations = {
1016 .setattr = affs_notify_change,
1017 };
1018