1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/fs/affs/file.c
4 *
5 * (c) 1996 Hans-Joachim Widmaier - Rewritten
6 *
7 * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.
8 *
9 * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem.
10 *
11 * (C) 1991 Linus Torvalds - minix filesystem
12 *
13 * affs regular file handling primitives
14 */
15
16 #include <linux/uio.h>
17 #include <linux/blkdev.h>
18 #include "affs.h"
19
20 static struct buffer_head *affs_get_extblock_slow(struct inode *inode, u32 ext);
21
22 static int
affs_file_open(struct inode * inode,struct file * filp)23 affs_file_open(struct inode *inode, struct file *filp)
24 {
25 pr_debug("open(%lu,%d)\n",
26 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
27 atomic_inc(&AFFS_I(inode)->i_opencnt);
28 return 0;
29 }
30
31 static int
affs_file_release(struct inode * inode,struct file * filp)32 affs_file_release(struct inode *inode, struct file *filp)
33 {
34 pr_debug("release(%lu, %d)\n",
35 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt));
36
37 if (atomic_dec_and_test(&AFFS_I(inode)->i_opencnt)) {
38 inode_lock(inode);
39 if (inode->i_size != AFFS_I(inode)->mmu_private)
40 affs_truncate(inode);
41 affs_free_prealloc(inode);
42 inode_unlock(inode);
43 }
44
45 return 0;
46 }
47
48 static int
affs_grow_extcache(struct inode * inode,u32 lc_idx)49 affs_grow_extcache(struct inode *inode, u32 lc_idx)
50 {
51 struct super_block *sb = inode->i_sb;
52 struct buffer_head *bh;
53 u32 lc_max;
54 int i, j, key;
55
56 if (!AFFS_I(inode)->i_lc) {
57 char *ptr = (char *)get_zeroed_page(GFP_NOFS);
58 if (!ptr)
59 return -ENOMEM;
60 AFFS_I(inode)->i_lc = (u32 *)ptr;
61 AFFS_I(inode)->i_ac = (struct affs_ext_key *)(ptr + AFFS_CACHE_SIZE / 2);
62 }
63
64 lc_max = AFFS_LC_SIZE << AFFS_I(inode)->i_lc_shift;
65
66 if (AFFS_I(inode)->i_extcnt > lc_max) {
67 u32 lc_shift, lc_mask, tmp, off;
68
69 /* need to recalculate linear cache, start from old size */
70 lc_shift = AFFS_I(inode)->i_lc_shift;
71 tmp = (AFFS_I(inode)->i_extcnt / AFFS_LC_SIZE) >> lc_shift;
72 for (; tmp; tmp >>= 1)
73 lc_shift++;
74 lc_mask = (1 << lc_shift) - 1;
75
76 /* fix idx and old size to new shift */
77 lc_idx >>= (lc_shift - AFFS_I(inode)->i_lc_shift);
78 AFFS_I(inode)->i_lc_size >>= (lc_shift - AFFS_I(inode)->i_lc_shift);
79
80 /* first shrink old cache to make more space */
81 off = 1 << (lc_shift - AFFS_I(inode)->i_lc_shift);
82 for (i = 1, j = off; j < AFFS_LC_SIZE; i++, j += off)
83 AFFS_I(inode)->i_ac[i] = AFFS_I(inode)->i_ac[j];
84
85 AFFS_I(inode)->i_lc_shift = lc_shift;
86 AFFS_I(inode)->i_lc_mask = lc_mask;
87 }
88
89 /* fill cache to the needed index */
90 i = AFFS_I(inode)->i_lc_size;
91 AFFS_I(inode)->i_lc_size = lc_idx + 1;
92 for (; i <= lc_idx; i++) {
93 if (!i) {
94 AFFS_I(inode)->i_lc[0] = inode->i_ino;
95 continue;
96 }
97 key = AFFS_I(inode)->i_lc[i - 1];
98 j = AFFS_I(inode)->i_lc_mask + 1;
99 // unlock cache
100 for (; j > 0; j--) {
101 bh = affs_bread(sb, key);
102 if (!bh)
103 goto err;
104 key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
105 affs_brelse(bh);
106 }
107 // lock cache
108 AFFS_I(inode)->i_lc[i] = key;
109 }
110
111 return 0;
112
113 err:
114 // lock cache
115 return -EIO;
116 }
117
118 static struct buffer_head *
affs_alloc_extblock(struct inode * inode,struct buffer_head * bh,u32 ext)119 affs_alloc_extblock(struct inode *inode, struct buffer_head *bh, u32 ext)
120 {
121 struct super_block *sb = inode->i_sb;
122 struct buffer_head *new_bh;
123 u32 blocknr, tmp;
124
125 blocknr = affs_alloc_block(inode, bh->b_blocknr);
126 if (!blocknr)
127 return ERR_PTR(-ENOSPC);
128
129 new_bh = affs_getzeroblk(sb, blocknr);
130 if (!new_bh) {
131 affs_free_block(sb, blocknr);
132 return ERR_PTR(-EIO);
133 }
134
135 AFFS_HEAD(new_bh)->ptype = cpu_to_be32(T_LIST);
136 AFFS_HEAD(new_bh)->key = cpu_to_be32(blocknr);
137 AFFS_TAIL(sb, new_bh)->stype = cpu_to_be32(ST_FILE);
138 AFFS_TAIL(sb, new_bh)->parent = cpu_to_be32(inode->i_ino);
139 affs_fix_checksum(sb, new_bh);
140
141 mark_buffer_dirty_inode(new_bh, inode);
142
143 tmp = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
144 if (tmp)
145 affs_warning(sb, "alloc_ext", "previous extension set (%x)", tmp);
146 AFFS_TAIL(sb, bh)->extension = cpu_to_be32(blocknr);
147 affs_adjust_checksum(bh, blocknr - tmp);
148 mark_buffer_dirty_inode(bh, inode);
149
150 AFFS_I(inode)->i_extcnt++;
151 mark_inode_dirty(inode);
152
153 return new_bh;
154 }
155
156 static inline struct buffer_head *
affs_get_extblock(struct inode * inode,u32 ext)157 affs_get_extblock(struct inode *inode, u32 ext)
158 {
159 /* inline the simplest case: same extended block as last time */
160 struct buffer_head *bh = AFFS_I(inode)->i_ext_bh;
161 if (ext == AFFS_I(inode)->i_ext_last)
162 get_bh(bh);
163 else
164 /* we have to do more (not inlined) */
165 bh = affs_get_extblock_slow(inode, ext);
166
167 return bh;
168 }
169
170 static struct buffer_head *
affs_get_extblock_slow(struct inode * inode,u32 ext)171 affs_get_extblock_slow(struct inode *inode, u32 ext)
172 {
173 struct super_block *sb = inode->i_sb;
174 struct buffer_head *bh;
175 u32 ext_key;
176 u32 lc_idx, lc_off, ac_idx;
177 u32 tmp, idx;
178
179 if (ext == AFFS_I(inode)->i_ext_last + 1) {
180 /* read the next extended block from the current one */
181 bh = AFFS_I(inode)->i_ext_bh;
182 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
183 if (ext < AFFS_I(inode)->i_extcnt)
184 goto read_ext;
185 BUG_ON(ext > AFFS_I(inode)->i_extcnt);
186 bh = affs_alloc_extblock(inode, bh, ext);
187 if (IS_ERR(bh))
188 return bh;
189 goto store_ext;
190 }
191
192 if (ext == 0) {
193 /* we seek back to the file header block */
194 ext_key = inode->i_ino;
195 goto read_ext;
196 }
197
198 if (ext >= AFFS_I(inode)->i_extcnt) {
199 struct buffer_head *prev_bh;
200
201 /* allocate a new extended block */
202 BUG_ON(ext > AFFS_I(inode)->i_extcnt);
203
204 /* get previous extended block */
205 prev_bh = affs_get_extblock(inode, ext - 1);
206 if (IS_ERR(prev_bh))
207 return prev_bh;
208 bh = affs_alloc_extblock(inode, prev_bh, ext);
209 affs_brelse(prev_bh);
210 if (IS_ERR(bh))
211 return bh;
212 goto store_ext;
213 }
214
215 again:
216 /* check if there is an extended cache and whether it's large enough */
217 lc_idx = ext >> AFFS_I(inode)->i_lc_shift;
218 lc_off = ext & AFFS_I(inode)->i_lc_mask;
219
220 if (lc_idx >= AFFS_I(inode)->i_lc_size) {
221 int err;
222
223 err = affs_grow_extcache(inode, lc_idx);
224 if (err)
225 return ERR_PTR(err);
226 goto again;
227 }
228
229 /* every n'th key we find in the linear cache */
230 if (!lc_off) {
231 ext_key = AFFS_I(inode)->i_lc[lc_idx];
232 goto read_ext;
233 }
234
235 /* maybe it's still in the associative cache */
236 ac_idx = (ext - lc_idx - 1) & AFFS_AC_MASK;
237 if (AFFS_I(inode)->i_ac[ac_idx].ext == ext) {
238 ext_key = AFFS_I(inode)->i_ac[ac_idx].key;
239 goto read_ext;
240 }
241
242 /* try to find one of the previous extended blocks */
243 tmp = ext;
244 idx = ac_idx;
245 while (--tmp, --lc_off > 0) {
246 idx = (idx - 1) & AFFS_AC_MASK;
247 if (AFFS_I(inode)->i_ac[idx].ext == tmp) {
248 ext_key = AFFS_I(inode)->i_ac[idx].key;
249 goto find_ext;
250 }
251 }
252
253 /* fall back to the linear cache */
254 ext_key = AFFS_I(inode)->i_lc[lc_idx];
255 find_ext:
256 /* read all extended blocks until we find the one we need */
257 //unlock cache
258 do {
259 bh = affs_bread(sb, ext_key);
260 if (!bh)
261 goto err_bread;
262 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension);
263 affs_brelse(bh);
264 tmp++;
265 } while (tmp < ext);
266 //lock cache
267
268 /* store it in the associative cache */
269 // recalculate ac_idx?
270 AFFS_I(inode)->i_ac[ac_idx].ext = ext;
271 AFFS_I(inode)->i_ac[ac_idx].key = ext_key;
272
273 read_ext:
274 /* finally read the right extended block */
275 //unlock cache
276 bh = affs_bread(sb, ext_key);
277 if (!bh)
278 goto err_bread;
279 //lock cache
280
281 store_ext:
282 /* release old cached extended block and store the new one */
283 affs_brelse(AFFS_I(inode)->i_ext_bh);
284 AFFS_I(inode)->i_ext_last = ext;
285 AFFS_I(inode)->i_ext_bh = bh;
286 get_bh(bh);
287
288 return bh;
289
290 err_bread:
291 affs_brelse(bh);
292 return ERR_PTR(-EIO);
293 }
294
295 static int
affs_get_block(struct inode * inode,sector_t block,struct buffer_head * bh_result,int create)296 affs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh_result, int create)
297 {
298 struct super_block *sb = inode->i_sb;
299 struct buffer_head *ext_bh;
300 u32 ext;
301
302 pr_debug("%s(%lu, %llu)\n", __func__, inode->i_ino,
303 (unsigned long long)block);
304
305 BUG_ON(block > (sector_t)0x7fffffffUL);
306
307 if (block >= AFFS_I(inode)->i_blkcnt) {
308 if (block > AFFS_I(inode)->i_blkcnt || !create)
309 goto err_big;
310 } else
311 create = 0;
312
313 //lock cache
314 affs_lock_ext(inode);
315
316 ext = (u32)block / AFFS_SB(sb)->s_hashsize;
317 block -= ext * AFFS_SB(sb)->s_hashsize;
318 ext_bh = affs_get_extblock(inode, ext);
319 if (IS_ERR(ext_bh))
320 goto err_ext;
321 map_bh(bh_result, sb, (sector_t)be32_to_cpu(AFFS_BLOCK(sb, ext_bh, block)));
322
323 if (create) {
324 u32 blocknr = affs_alloc_block(inode, ext_bh->b_blocknr);
325 if (!blocknr)
326 goto err_alloc;
327 set_buffer_new(bh_result);
328 AFFS_I(inode)->mmu_private += AFFS_SB(sb)->s_data_blksize;
329 AFFS_I(inode)->i_blkcnt++;
330
331 /* store new block */
332 if (bh_result->b_blocknr)
333 affs_warning(sb, "get_block",
334 "block already set (%llx)",
335 (unsigned long long)bh_result->b_blocknr);
336 AFFS_BLOCK(sb, ext_bh, block) = cpu_to_be32(blocknr);
337 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(block + 1);
338 affs_adjust_checksum(ext_bh, blocknr - bh_result->b_blocknr + 1);
339 bh_result->b_blocknr = blocknr;
340
341 if (!block) {
342 /* insert first block into header block */
343 u32 tmp = be32_to_cpu(AFFS_HEAD(ext_bh)->first_data);
344 if (tmp)
345 affs_warning(sb, "get_block", "first block already set (%d)", tmp);
346 AFFS_HEAD(ext_bh)->first_data = cpu_to_be32(blocknr);
347 affs_adjust_checksum(ext_bh, blocknr - tmp);
348 }
349 }
350
351 affs_brelse(ext_bh);
352 //unlock cache
353 affs_unlock_ext(inode);
354 return 0;
355
356 err_big:
357 affs_error(inode->i_sb, "get_block", "strange block request %llu",
358 (unsigned long long)block);
359 return -EIO;
360 err_ext:
361 // unlock cache
362 affs_unlock_ext(inode);
363 return PTR_ERR(ext_bh);
364 err_alloc:
365 brelse(ext_bh);
366 clear_buffer_mapped(bh_result);
367 bh_result->b_bdev = NULL;
368 // unlock cache
369 affs_unlock_ext(inode);
370 return -ENOSPC;
371 }
372
affs_writepage(struct page * page,struct writeback_control * wbc)373 static int affs_writepage(struct page *page, struct writeback_control *wbc)
374 {
375 return block_write_full_page(page, affs_get_block, wbc);
376 }
377
affs_read_folio(struct file * file,struct folio * folio)378 static int affs_read_folio(struct file *file, struct folio *folio)
379 {
380 return block_read_full_folio(folio, affs_get_block);
381 }
382
affs_write_failed(struct address_space * mapping,loff_t to)383 static void affs_write_failed(struct address_space *mapping, loff_t to)
384 {
385 struct inode *inode = mapping->host;
386
387 if (to > inode->i_size) {
388 truncate_pagecache(inode, inode->i_size);
389 affs_truncate(inode);
390 }
391 }
392
393 static ssize_t
affs_direct_IO(struct kiocb * iocb,struct iov_iter * iter)394 affs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
395 {
396 struct file *file = iocb->ki_filp;
397 struct address_space *mapping = file->f_mapping;
398 struct inode *inode = mapping->host;
399 size_t count = iov_iter_count(iter);
400 loff_t offset = iocb->ki_pos;
401 ssize_t ret;
402
403 if (iov_iter_rw(iter) == WRITE) {
404 loff_t size = offset + count;
405
406 if (AFFS_I(inode)->mmu_private < size)
407 return 0;
408 }
409
410 ret = blockdev_direct_IO(iocb, inode, iter, affs_get_block);
411 if (ret < 0 && iov_iter_rw(iter) == WRITE)
412 affs_write_failed(mapping, offset + count);
413 return ret;
414 }
415
affs_write_begin(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,struct page ** pagep,void ** fsdata)416 static 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
affs_write_end(struct file * file,struct address_space * mapping,loff_t pos,unsigned int len,unsigned int copied,struct page * page,void * fsdata)432 static int affs_write_end(struct file *file, struct address_space *mapping,
433 loff_t pos, unsigned int len, unsigned int copied,
434 struct page *page, void *fsdata)
435 {
436 struct inode *inode = mapping->host;
437 int ret;
438
439 ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
440
441 /* Clear Archived bit on file writes, as AmigaOS would do */
442 if (AFFS_I(inode)->i_protect & FIBF_ARCHIVED) {
443 AFFS_I(inode)->i_protect &= ~FIBF_ARCHIVED;
444 mark_inode_dirty(inode);
445 }
446
447 return ret;
448 }
449
_affs_bmap(struct address_space * mapping,sector_t block)450 static sector_t _affs_bmap(struct address_space *mapping, sector_t block)
451 {
452 return generic_block_bmap(mapping,block,affs_get_block);
453 }
454
455 const struct address_space_operations affs_aops = {
456 .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
466 static inline struct buffer_head *
affs_bread_ino(struct inode * inode,int block,int create)467 affs_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
485 static inline struct buffer_head *
affs_getzeroblk_ino(struct inode * inode,int block)486 affs_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
504 static inline struct buffer_head *
affs_getemptyblk_ino(struct inode * inode,int block)505 affs_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
523 static int
affs_do_readpage_ofs(struct page * page,unsigned to,int create)524 affs_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 char *data;
530 unsigned pos = 0;
531 u32 bidx, boff, bsize;
532 u32 tmp;
533
534 pr_debug("%s(%lu, %ld, 0, %d)\n", __func__, inode->i_ino,
535 page->index, to);
536 BUG_ON(to > PAGE_SIZE);
537 bsize = AFFS_SB(sb)->s_data_blksize;
538 tmp = page->index << PAGE_SHIFT;
539 bidx = tmp / bsize;
540 boff = tmp % bsize;
541
542 while (pos < to) {
543 bh = affs_bread_ino(inode, bidx, create);
544 if (IS_ERR(bh))
545 return PTR_ERR(bh);
546 tmp = min(bsize - boff, to - pos);
547 BUG_ON(pos + tmp > to || tmp > bsize);
548 data = kmap_atomic(page);
549 memcpy(data + pos, AFFS_DATA(bh) + boff, tmp);
550 kunmap_atomic(data);
551 affs_brelse(bh);
552 bidx++;
553 pos += tmp;
554 boff = 0;
555 }
556 flush_dcache_page(page);
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);
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
631 static int
affs_read_folio_ofs(struct file * file,struct folio * folio)632 affs_read_folio_ofs(struct file *file, struct folio *folio)
633 {
634 struct page *page = &folio->page;
635 struct inode *inode = page->mapping->host;
636 u32 to;
637 int err;
638
639 pr_debug("%s(%lu, %ld)\n", __func__, inode->i_ino, page->index);
640 to = PAGE_SIZE;
641 if (((page->index + 1) << PAGE_SHIFT) > inode->i_size) {
642 to = inode->i_size & ~PAGE_MASK;
643 memset(page_address(page) + to, 0, PAGE_SIZE - to);
644 }
645
646 err = affs_do_readpage_ofs(page, to, 0);
647 if (!err)
648 SetPageUptodate(page);
649 unlock_page(page);
650 return err;
651 }
652
affs_write_begin_ofs(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,struct page ** pagep,void ** fsdata)653 static int affs_write_begin_ofs(struct file *file, struct address_space *mapping,
654 loff_t pos, unsigned len,
655 struct page **pagep, void **fsdata)
656 {
657 struct inode *inode = mapping->host;
658 struct page *page;
659 pgoff_t index;
660 int err = 0;
661
662 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos,
663 pos + len);
664 if (pos > AFFS_I(inode)->mmu_private) {
665 /* XXX: this probably leaves a too-big i_size in case of
666 * failure. Should really be updating i_size at write_end time
667 */
668 err = affs_extent_file_ofs(inode, pos);
669 if (err)
670 return err;
671 }
672
673 index = pos >> PAGE_SHIFT;
674 page = grab_cache_page_write_begin(mapping, index);
675 if (!page)
676 return -ENOMEM;
677 *pagep = page;
678
679 if (PageUptodate(page))
680 return 0;
681
682 /* XXX: inefficient but safe in the face of short writes */
683 err = affs_do_readpage_ofs(page, PAGE_SIZE, 1);
684 if (err) {
685 unlock_page(page);
686 put_page(page);
687 }
688 return err;
689 }
690
affs_write_end_ofs(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,unsigned copied,struct page * page,void * fsdata)691 static int affs_write_end_ofs(struct file *file, struct address_space *mapping,
692 loff_t pos, unsigned len, unsigned copied,
693 struct page *page, 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 page 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 = page_address(page);
716
717 bh = NULL;
718 written = 0;
719 tmp = (page->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 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp);
732 affs_fix_checksum(sb, bh);
733 mark_buffer_dirty_inode(bh, inode);
734 written += tmp;
735 from += tmp;
736 bidx++;
737 } else if (bidx) {
738 bh = affs_bread_ino(inode, bidx - 1, 0);
739 if (IS_ERR(bh)) {
740 written = PTR_ERR(bh);
741 goto err_first_bh;
742 }
743 }
744 while (from + bsize <= to) {
745 prev_bh = bh;
746 bh = affs_getemptyblk_ino(inode, bidx);
747 if (IS_ERR(bh))
748 goto err_bh;
749 memcpy(AFFS_DATA(bh), data + from, bsize);
750 if (buffer_new(bh)) {
751 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
752 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
753 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
754 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(bsize);
755 AFFS_DATA_HEAD(bh)->next = 0;
756 bh->b_state &= ~(1UL << BH_New);
757 if (prev_bh) {
758 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
759
760 if (tmp_next)
761 affs_warning(sb, "commit_write_ofs",
762 "next block already set for %d (%d)",
763 bidx, tmp_next);
764 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
765 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
766 mark_buffer_dirty_inode(prev_bh, inode);
767 }
768 }
769 affs_brelse(prev_bh);
770 affs_fix_checksum(sb, bh);
771 mark_buffer_dirty_inode(bh, inode);
772 written += bsize;
773 from += bsize;
774 bidx++;
775 }
776 if (from < to) {
777 prev_bh = bh;
778 bh = affs_bread_ino(inode, bidx, 1);
779 if (IS_ERR(bh))
780 goto err_bh;
781 tmp = min(bsize, to - from);
782 BUG_ON(tmp > bsize);
783 memcpy(AFFS_DATA(bh), data + from, tmp);
784 if (buffer_new(bh)) {
785 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA);
786 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino);
787 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx);
788 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
789 AFFS_DATA_HEAD(bh)->next = 0;
790 bh->b_state &= ~(1UL << BH_New);
791 if (prev_bh) {
792 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next);
793
794 if (tmp_next)
795 affs_warning(sb, "commit_write_ofs",
796 "next block already set for %d (%d)",
797 bidx, tmp_next);
798 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr);
799 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next);
800 mark_buffer_dirty_inode(prev_bh, inode);
801 }
802 } else if (be32_to_cpu(AFFS_DATA_HEAD(bh)->size) < tmp)
803 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp);
804 affs_brelse(prev_bh);
805 affs_fix_checksum(sb, bh);
806 mark_buffer_dirty_inode(bh, inode);
807 written += tmp;
808 from += tmp;
809 bidx++;
810 }
811 SetPageUptodate(page);
812
813 done:
814 affs_brelse(bh);
815 tmp = (page->index << PAGE_SHIFT) + from;
816 if (tmp > inode->i_size)
817 inode->i_size = AFFS_I(inode)->mmu_private = tmp;
818
819 /* Clear Archived bit on file writes, as AmigaOS would do */
820 if (AFFS_I(inode)->i_protect & FIBF_ARCHIVED) {
821 AFFS_I(inode)->i_protect &= ~FIBF_ARCHIVED;
822 mark_inode_dirty(inode);
823 }
824
825 err_first_bh:
826 unlock_page(page);
827 put_page(page);
828
829 return written;
830
831 err_bh:
832 bh = prev_bh;
833 if (!written)
834 written = PTR_ERR(bh);
835 goto done;
836 }
837
838 const struct address_space_operations affs_aops_ofs = {
839 .dirty_folio = block_dirty_folio,
840 .invalidate_folio = block_invalidate_folio,
841 .read_folio = affs_read_folio_ofs,
842 //.writepage = affs_writepage_ofs,
843 .write_begin = affs_write_begin_ofs,
844 .write_end = affs_write_end_ofs
845 };
846
847 /* Free any preallocated blocks. */
848
849 void
affs_free_prealloc(struct inode * inode)850 affs_free_prealloc(struct inode *inode)
851 {
852 struct super_block *sb = inode->i_sb;
853
854 pr_debug("free_prealloc(ino=%lu)\n", inode->i_ino);
855
856 while (AFFS_I(inode)->i_pa_cnt) {
857 AFFS_I(inode)->i_pa_cnt--;
858 affs_free_block(sb, ++AFFS_I(inode)->i_lastalloc);
859 }
860 }
861
862 /* Truncate (or enlarge) a file to the requested size. */
863
864 void
affs_truncate(struct inode * inode)865 affs_truncate(struct inode *inode)
866 {
867 struct super_block *sb = inode->i_sb;
868 u32 ext, ext_key;
869 u32 last_blk, blkcnt, blk;
870 u32 size;
871 struct buffer_head *ext_bh;
872 int i;
873
874 pr_debug("truncate(inode=%lu, oldsize=%llu, newsize=%llu)\n",
875 inode->i_ino, AFFS_I(inode)->mmu_private, inode->i_size);
876
877 last_blk = 0;
878 ext = 0;
879 if (inode->i_size) {
880 last_blk = ((u32)inode->i_size - 1) / AFFS_SB(sb)->s_data_blksize;
881 ext = last_blk / AFFS_SB(sb)->s_hashsize;
882 }
883
884 if (inode->i_size > AFFS_I(inode)->mmu_private) {
885 struct address_space *mapping = inode->i_mapping;
886 struct page *page;
887 void *fsdata;
888 loff_t isize = inode->i_size;
889 int res;
890
891 res = mapping->a_ops->write_begin(NULL, mapping, isize, 0, &page, &fsdata);
892 if (!res)
893 res = mapping->a_ops->write_end(NULL, mapping, isize, 0, 0, page, fsdata);
894 else
895 inode->i_size = AFFS_I(inode)->mmu_private;
896 mark_inode_dirty(inode);
897 return;
898 } else if (inode->i_size == AFFS_I(inode)->mmu_private)
899 return;
900
901 // lock cache
902 ext_bh = affs_get_extblock(inode, ext);
903 if (IS_ERR(ext_bh)) {
904 affs_warning(sb, "truncate",
905 "unexpected read error for ext block %u (%ld)",
906 ext, PTR_ERR(ext_bh));
907 return;
908 }
909 if (AFFS_I(inode)->i_lc) {
910 /* clear linear cache */
911 i = (ext + 1) >> AFFS_I(inode)->i_lc_shift;
912 if (AFFS_I(inode)->i_lc_size > i) {
913 AFFS_I(inode)->i_lc_size = i;
914 for (; i < AFFS_LC_SIZE; i++)
915 AFFS_I(inode)->i_lc[i] = 0;
916 }
917 /* clear associative cache */
918 for (i = 0; i < AFFS_AC_SIZE; i++)
919 if (AFFS_I(inode)->i_ac[i].ext >= ext)
920 AFFS_I(inode)->i_ac[i].ext = 0;
921 }
922 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
923
924 blkcnt = AFFS_I(inode)->i_blkcnt;
925 i = 0;
926 blk = last_blk;
927 if (inode->i_size) {
928 i = last_blk % AFFS_SB(sb)->s_hashsize + 1;
929 blk++;
930 } else
931 AFFS_HEAD(ext_bh)->first_data = 0;
932 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(i);
933 size = AFFS_SB(sb)->s_hashsize;
934 if (size > blkcnt - blk + i)
935 size = blkcnt - blk + i;
936 for (; i < size; i++, blk++) {
937 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
938 AFFS_BLOCK(sb, ext_bh, i) = 0;
939 }
940 AFFS_TAIL(sb, ext_bh)->extension = 0;
941 affs_fix_checksum(sb, ext_bh);
942 mark_buffer_dirty_inode(ext_bh, inode);
943 affs_brelse(ext_bh);
944
945 if (inode->i_size) {
946 AFFS_I(inode)->i_blkcnt = last_blk + 1;
947 AFFS_I(inode)->i_extcnt = ext + 1;
948 if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_OFS)) {
949 struct buffer_head *bh = affs_bread_ino(inode, last_blk, 0);
950 u32 tmp;
951 if (IS_ERR(bh)) {
952 affs_warning(sb, "truncate",
953 "unexpected read error for last block %u (%ld)",
954 ext, PTR_ERR(bh));
955 return;
956 }
957 tmp = be32_to_cpu(AFFS_DATA_HEAD(bh)->next);
958 AFFS_DATA_HEAD(bh)->next = 0;
959 affs_adjust_checksum(bh, -tmp);
960 affs_brelse(bh);
961 }
962 } else {
963 AFFS_I(inode)->i_blkcnt = 0;
964 AFFS_I(inode)->i_extcnt = 1;
965 }
966 AFFS_I(inode)->mmu_private = inode->i_size;
967 // unlock cache
968
969 while (ext_key) {
970 ext_bh = affs_bread(sb, ext_key);
971 size = AFFS_SB(sb)->s_hashsize;
972 if (size > blkcnt - blk)
973 size = blkcnt - blk;
974 for (i = 0; i < size; i++, blk++)
975 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i)));
976 affs_free_block(sb, ext_key);
977 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension);
978 affs_brelse(ext_bh);
979 }
980 affs_free_prealloc(inode);
981 }
982
affs_file_fsync(struct file * filp,loff_t start,loff_t end,int datasync)983 int affs_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
984 {
985 struct inode *inode = filp->f_mapping->host;
986 int ret, err;
987
988 err = file_write_and_wait_range(filp, start, end);
989 if (err)
990 return err;
991
992 inode_lock(inode);
993 ret = write_inode_now(inode, 0);
994 err = sync_blockdev(inode->i_sb->s_bdev);
995 if (!ret)
996 ret = err;
997 inode_unlock(inode);
998 return ret;
999 }
1000 const struct file_operations affs_file_operations = {
1001 .llseek = generic_file_llseek,
1002 .read_iter = generic_file_read_iter,
1003 .write_iter = generic_file_write_iter,
1004 .mmap = generic_file_mmap,
1005 .open = affs_file_open,
1006 .release = affs_file_release,
1007 .fsync = affs_file_fsync,
1008 .splice_read = generic_file_splice_read,
1009 };
1010
1011 const struct inode_operations affs_file_inode_operations = {
1012 .setattr = affs_notify_change,
1013 };
1014