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 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
556 static int
affs_extent_file_ofs(struct inode * inode,u32 newsize)557 affs_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
622 out:
623 inode->i_size = AFFS_I(inode)->mmu_private = newsize;
624 return PTR_ERR(bh);
625 }
626
627 static int
affs_read_folio_ofs(struct file * file,struct folio * folio)628 affs_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
affs_write_begin_ofs(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,struct page ** pagep,void ** fsdata)649 static 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
affs_write_end_ofs(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,unsigned copied,struct page * page,void * fsdata)687 static 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
809 done:
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
821 err_first_bh:
822 unlock_page(page);
823 put_page(page);
824
825 return written;
826
827 err_bh:
828 bh = prev_bh;
829 if (!written)
830 written = PTR_ERR(bh);
831 goto done;
832 }
833
834 const 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
845 void
affs_free_prealloc(struct inode * inode)846 affs_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
860 void
affs_truncate(struct inode * inode)861 affs_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
affs_file_fsync(struct file * filp,loff_t start,loff_t end,int datasync)979 int 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 }
996 const 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
1007 const struct inode_operations affs_file_inode_operations = {
1008 .setattr = affs_notify_change,
1009 };
1010