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 21static struct buffer_head *affs_get_extblock_slow(struct inode *inode, u32 ext); 22 23static int 24affs_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 32static int 33affs_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 49static int 50affs_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 114err: 115 // lock cache 116 return -EIO; 117} 118 119static struct buffer_head * 120affs_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 157static inline struct buffer_head * 158affs_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 171static struct buffer_head * 172affs_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 216again: 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]; 256find_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 274read_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 282store_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 291err_bread: 292 affs_brelse(bh); 293 return ERR_PTR(-EIO); 294} 295 296static int 297affs_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 357err_big: 358 affs_error(inode->i_sb, "get_block", "strange block request %llu", 359 (unsigned long long)block); 360 return -EIO; 361err_ext: 362 // unlock cache 363 affs_unlock_ext(inode); 364 return PTR_ERR(ext_bh); 365err_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 374static int affs_writepages(struct address_space *mapping, 375 struct writeback_control *wbc) 376{ 377 return mpage_writepages(mapping, wbc, affs_get_block); 378} 379 380static int affs_read_folio(struct file *file, struct folio *folio) 381{ 382 return block_read_full_folio(folio, affs_get_block); 383} 384 385static 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 395static ssize_t 396affs_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 418static int affs_write_begin(struct file *file, struct address_space *mapping, 419 loff_t pos, unsigned len, 420 struct page **pagep, void **fsdata) 421{ 422 int ret; 423 424 *pagep = NULL; 425 ret = cont_write_begin(file, mapping, pos, len, pagep, 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 434static int affs_write_end(struct file *file, struct address_space *mapping, 435 loff_t pos, unsigned int len, unsigned int copied, 436 struct page *page, void *fsdata) 437{ 438 struct inode *inode = mapping->host; 439 int ret; 440 441 ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata); 442 443 /* Clear Archived bit on file writes, as AmigaOS would do */ 444 if (AFFS_I(inode)->i_protect & FIBF_ARCHIVED) { 445 AFFS_I(inode)->i_protect &= ~FIBF_ARCHIVED; 446 mark_inode_dirty(inode); 447 } 448 449 return ret; 450} 451 452static sector_t _affs_bmap(struct address_space *mapping, sector_t block) 453{ 454 return generic_block_bmap(mapping,block,affs_get_block); 455} 456 457const struct address_space_operations affs_aops = { 458 .dirty_folio = block_dirty_folio, 459 .invalidate_folio = block_invalidate_folio, 460 .read_folio = affs_read_folio, 461 .writepages = affs_writepages, 462 .write_begin = affs_write_begin, 463 .write_end = affs_write_end, 464 .direct_IO = affs_direct_IO, 465 .migrate_folio = buffer_migrate_folio, 466 .bmap = _affs_bmap 467}; 468 469static inline struct buffer_head * 470affs_bread_ino(struct inode *inode, int block, int create) 471{ 472 struct buffer_head *bh, tmp_bh; 473 int err; 474 475 tmp_bh.b_state = 0; 476 err = affs_get_block(inode, block, &tmp_bh, create); 477 if (!err) { 478 bh = affs_bread(inode->i_sb, tmp_bh.b_blocknr); 479 if (bh) { 480 bh->b_state |= tmp_bh.b_state; 481 return bh; 482 } 483 err = -EIO; 484 } 485 return ERR_PTR(err); 486} 487 488static inline struct buffer_head * 489affs_getzeroblk_ino(struct inode *inode, int block) 490{ 491 struct buffer_head *bh, tmp_bh; 492 int err; 493 494 tmp_bh.b_state = 0; 495 err = affs_get_block(inode, block, &tmp_bh, 1); 496 if (!err) { 497 bh = affs_getzeroblk(inode->i_sb, tmp_bh.b_blocknr); 498 if (bh) { 499 bh->b_state |= tmp_bh.b_state; 500 return bh; 501 } 502 err = -EIO; 503 } 504 return ERR_PTR(err); 505} 506 507static inline struct buffer_head * 508affs_getemptyblk_ino(struct inode *inode, int block) 509{ 510 struct buffer_head *bh, tmp_bh; 511 int err; 512 513 tmp_bh.b_state = 0; 514 err = affs_get_block(inode, block, &tmp_bh, 1); 515 if (!err) { 516 bh = affs_getemptyblk(inode->i_sb, tmp_bh.b_blocknr); 517 if (bh) { 518 bh->b_state |= tmp_bh.b_state; 519 return bh; 520 } 521 err = -EIO; 522 } 523 return ERR_PTR(err); 524} 525 526static int affs_do_read_folio_ofs(struct folio *folio, size_t to, int create) 527{ 528 struct inode *inode = folio->mapping->host; 529 struct super_block *sb = inode->i_sb; 530 struct buffer_head *bh; 531 size_t pos = 0; 532 size_t bidx, boff, bsize; 533 u32 tmp; 534 535 pr_debug("%s(%lu, %ld, 0, %zu)\n", __func__, inode->i_ino, 536 folio->index, to); 537 BUG_ON(to > folio_size(folio)); 538 bsize = AFFS_SB(sb)->s_data_blksize; 539 tmp = folio_pos(folio); 540 bidx = tmp / bsize; 541 boff = tmp % bsize; 542 543 while (pos < to) { 544 bh = affs_bread_ino(inode, bidx, create); 545 if (IS_ERR(bh)) 546 return PTR_ERR(bh); 547 tmp = min(bsize - boff, to - pos); 548 BUG_ON(pos + tmp > to || tmp > bsize); 549 memcpy_to_folio(folio, pos, AFFS_DATA(bh) + boff, tmp); 550 affs_brelse(bh); 551 bidx++; 552 pos += tmp; 553 boff = 0; 554 } 555 return 0; 556} 557 558static int 559affs_extent_file_ofs(struct inode *inode, u32 newsize) 560{ 561 struct super_block *sb = inode->i_sb; 562 struct buffer_head *bh, *prev_bh; 563 u32 bidx, boff; 564 u32 size, bsize; 565 u32 tmp; 566 567 pr_debug("%s(%lu, %d)\n", __func__, inode->i_ino, newsize); 568 bsize = AFFS_SB(sb)->s_data_blksize; 569 bh = NULL; 570 size = AFFS_I(inode)->mmu_private; 571 bidx = size / bsize; 572 boff = size % bsize; 573 if (boff) { 574 bh = affs_bread_ino(inode, bidx, 0); 575 if (IS_ERR(bh)) 576 return PTR_ERR(bh); 577 tmp = min(bsize - boff, newsize - size); 578 BUG_ON(boff + tmp > bsize || tmp > bsize); 579 memset(AFFS_DATA(bh) + boff, 0, tmp); 580 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp); 581 affs_fix_checksum(sb, bh); 582 mark_buffer_dirty_inode(bh, inode); 583 size += tmp; 584 bidx++; 585 } else if (bidx) { 586 bh = affs_bread_ino(inode, bidx - 1, 0); 587 if (IS_ERR(bh)) 588 return PTR_ERR(bh); 589 } 590 591 while (size < newsize) { 592 prev_bh = bh; 593 bh = affs_getzeroblk_ino(inode, bidx); 594 if (IS_ERR(bh)) 595 goto out; 596 tmp = min(bsize, newsize - size); 597 BUG_ON(tmp > bsize); 598 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); 599 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); 600 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); 601 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); 602 affs_fix_checksum(sb, bh); 603 bh->b_state &= ~(1UL << BH_New); 604 mark_buffer_dirty_inode(bh, inode); 605 if (prev_bh) { 606 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); 607 608 if (tmp_next) 609 affs_warning(sb, "extent_file_ofs", 610 "next block already set for %d (%d)", 611 bidx, tmp_next); 612 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); 613 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next); 614 mark_buffer_dirty_inode(prev_bh, inode); 615 affs_brelse(prev_bh); 616 } 617 size += bsize; 618 bidx++; 619 } 620 affs_brelse(bh); 621 inode->i_size = AFFS_I(inode)->mmu_private = newsize; 622 return 0; 623 624out: 625 inode->i_size = AFFS_I(inode)->mmu_private = newsize; 626 return PTR_ERR(bh); 627} 628 629static int affs_read_folio_ofs(struct file *file, struct folio *folio) 630{ 631 struct inode *inode = folio->mapping->host; 632 size_t to; 633 int err; 634 635 pr_debug("%s(%lu, %ld)\n", __func__, inode->i_ino, folio->index); 636 to = folio_size(folio); 637 if (folio_pos(folio) + to > inode->i_size) { 638 to = inode->i_size - folio_pos(folio); 639 folio_zero_segment(folio, to, folio_size(folio)); 640 } 641 642 err = affs_do_read_folio_ofs(folio, to, 0); 643 if (!err) 644 folio_mark_uptodate(folio); 645 folio_unlock(folio); 646 return err; 647} 648 649static int affs_write_begin_ofs(struct file *file, struct address_space *mapping, 650 loff_t pos, unsigned len, 651 struct page **pagep, void **fsdata) 652{ 653 struct inode *inode = mapping->host; 654 struct folio *folio; 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 folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN, 671 mapping_gfp_mask(mapping)); 672 if (IS_ERR(folio)) 673 return PTR_ERR(folio); 674 *pagep = &folio->page; 675 676 if (folio_test_uptodate(folio)) 677 return 0; 678 679 /* XXX: inefficient but safe in the face of short writes */ 680 err = affs_do_read_folio_ofs(folio, folio_size(folio), 1); 681 if (err) { 682 folio_unlock(folio); 683 folio_put(folio); 684 } 685 return err; 686} 687 688static int affs_write_end_ofs(struct file *file, struct address_space *mapping, 689 loff_t pos, unsigned len, unsigned copied, 690 struct page *page, void *fsdata) 691{ 692 struct folio *folio = page_folio(page); 693 struct inode *inode = mapping->host; 694 struct super_block *sb = inode->i_sb; 695 struct buffer_head *bh, *prev_bh; 696 char *data; 697 u32 bidx, boff, bsize; 698 unsigned from, to; 699 u32 tmp; 700 int written; 701 702 from = pos & (PAGE_SIZE - 1); 703 to = from + len; 704 /* 705 * XXX: not sure if this can handle short copies (len < copied), but 706 * we don't have to, because the folio should always be uptodate here, 707 * due to write_begin. 708 */ 709 710 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos, 711 pos + len); 712 bsize = AFFS_SB(sb)->s_data_blksize; 713 data = folio_address(folio); 714 715 bh = NULL; 716 written = 0; 717 tmp = (folio->index << PAGE_SHIFT) + from; 718 bidx = tmp / bsize; 719 boff = tmp % bsize; 720 if (boff) { 721 bh = affs_bread_ino(inode, bidx, 0); 722 if (IS_ERR(bh)) { 723 written = PTR_ERR(bh); 724 goto err_first_bh; 725 } 726 tmp = min(bsize - boff, to - from); 727 BUG_ON(boff + tmp > bsize || tmp > bsize); 728 memcpy(AFFS_DATA(bh) + boff, data + from, tmp); 729 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp); 730 affs_fix_checksum(sb, bh); 731 mark_buffer_dirty_inode(bh, inode); 732 written += tmp; 733 from += tmp; 734 bidx++; 735 } else if (bidx) { 736 bh = affs_bread_ino(inode, bidx - 1, 0); 737 if (IS_ERR(bh)) { 738 written = PTR_ERR(bh); 739 goto err_first_bh; 740 } 741 } 742 while (from + bsize <= to) { 743 prev_bh = bh; 744 bh = affs_getemptyblk_ino(inode, bidx); 745 if (IS_ERR(bh)) 746 goto err_bh; 747 memcpy(AFFS_DATA(bh), data + from, bsize); 748 if (buffer_new(bh)) { 749 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); 750 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); 751 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); 752 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(bsize); 753 AFFS_DATA_HEAD(bh)->next = 0; 754 bh->b_state &= ~(1UL << BH_New); 755 if (prev_bh) { 756 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); 757 758 if (tmp_next) 759 affs_warning(sb, "commit_write_ofs", 760 "next block already set for %d (%d)", 761 bidx, tmp_next); 762 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); 763 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next); 764 mark_buffer_dirty_inode(prev_bh, inode); 765 } 766 } 767 affs_brelse(prev_bh); 768 affs_fix_checksum(sb, bh); 769 mark_buffer_dirty_inode(bh, inode); 770 written += bsize; 771 from += bsize; 772 bidx++; 773 } 774 if (from < to) { 775 prev_bh = bh; 776 bh = affs_bread_ino(inode, bidx, 1); 777 if (IS_ERR(bh)) 778 goto err_bh; 779 tmp = min(bsize, to - from); 780 BUG_ON(tmp > bsize); 781 memcpy(AFFS_DATA(bh), data + from, tmp); 782 if (buffer_new(bh)) { 783 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); 784 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); 785 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); 786 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); 787 AFFS_DATA_HEAD(bh)->next = 0; 788 bh->b_state &= ~(1UL << BH_New); 789 if (prev_bh) { 790 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); 791 792 if (tmp_next) 793 affs_warning(sb, "commit_write_ofs", 794 "next block already set for %d (%d)", 795 bidx, tmp_next); 796 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); 797 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next); 798 mark_buffer_dirty_inode(prev_bh, inode); 799 } 800 } else if (be32_to_cpu(AFFS_DATA_HEAD(bh)->size) < tmp) 801 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); 802 affs_brelse(prev_bh); 803 affs_fix_checksum(sb, bh); 804 mark_buffer_dirty_inode(bh, inode); 805 written += tmp; 806 from += tmp; 807 bidx++; 808 } 809 folio_mark_uptodate(folio); 810 811done: 812 affs_brelse(bh); 813 tmp = (folio->index << PAGE_SHIFT) + from; 814 if (tmp > inode->i_size) 815 inode->i_size = AFFS_I(inode)->mmu_private = tmp; 816 817 /* Clear Archived bit on file writes, as AmigaOS would do */ 818 if (AFFS_I(inode)->i_protect & FIBF_ARCHIVED) { 819 AFFS_I(inode)->i_protect &= ~FIBF_ARCHIVED; 820 mark_inode_dirty(inode); 821 } 822 823err_first_bh: 824 folio_unlock(folio); 825 folio_put(folio); 826 827 return written; 828 829err_bh: 830 bh = prev_bh; 831 if (!written) 832 written = PTR_ERR(bh); 833 goto done; 834} 835 836const struct address_space_operations affs_aops_ofs = { 837 .dirty_folio = block_dirty_folio, 838 .invalidate_folio = block_invalidate_folio, 839 .read_folio = affs_read_folio_ofs, 840 //.writepages = affs_writepages_ofs, 841 .write_begin = affs_write_begin_ofs, 842 .write_end = affs_write_end_ofs, 843 .migrate_folio = filemap_migrate_folio, 844}; 845 846/* Free any preallocated blocks. */ 847 848void 849affs_free_prealloc(struct inode *inode) 850{ 851 struct super_block *sb = inode->i_sb; 852 853 pr_debug("free_prealloc(ino=%lu)\n", inode->i_ino); 854 855 while (AFFS_I(inode)->i_pa_cnt) { 856 AFFS_I(inode)->i_pa_cnt--; 857 affs_free_block(sb, ++AFFS_I(inode)->i_lastalloc); 858 } 859} 860 861/* Truncate (or enlarge) a file to the requested size. */ 862 863void 864affs_truncate(struct inode *inode) 865{ 866 struct super_block *sb = inode->i_sb; 867 u32 ext, ext_key; 868 u32 last_blk, blkcnt, blk; 869 u32 size; 870 struct buffer_head *ext_bh; 871 int i; 872 873 pr_debug("truncate(inode=%lu, oldsize=%llu, newsize=%llu)\n", 874 inode->i_ino, AFFS_I(inode)->mmu_private, inode->i_size); 875 876 last_blk = 0; 877 ext = 0; 878 if (inode->i_size) { 879 last_blk = ((u32)inode->i_size - 1) / AFFS_SB(sb)->s_data_blksize; 880 ext = last_blk / AFFS_SB(sb)->s_hashsize; 881 } 882 883 if (inode->i_size > AFFS_I(inode)->mmu_private) { 884 struct address_space *mapping = inode->i_mapping; 885 struct page *page; 886 void *fsdata = NULL; 887 loff_t isize = inode->i_size; 888 int res; 889 890 res = mapping->a_ops->write_begin(NULL, mapping, isize, 0, &page, &fsdata); 891 if (!res) 892 res = mapping->a_ops->write_end(NULL, mapping, isize, 0, 0, page, fsdata); 893 else 894 inode->i_size = AFFS_I(inode)->mmu_private; 895 mark_inode_dirty(inode); 896 return; 897 } else if (inode->i_size == AFFS_I(inode)->mmu_private) 898 return; 899 900 // lock cache 901 ext_bh = affs_get_extblock(inode, ext); 902 if (IS_ERR(ext_bh)) { 903 affs_warning(sb, "truncate", 904 "unexpected read error for ext block %u (%ld)", 905 ext, PTR_ERR(ext_bh)); 906 return; 907 } 908 if (AFFS_I(inode)->i_lc) { 909 /* clear linear cache */ 910 i = (ext + 1) >> AFFS_I(inode)->i_lc_shift; 911 if (AFFS_I(inode)->i_lc_size > i) { 912 AFFS_I(inode)->i_lc_size = i; 913 for (; i < AFFS_LC_SIZE; i++) 914 AFFS_I(inode)->i_lc[i] = 0; 915 } 916 /* clear associative cache */ 917 for (i = 0; i < AFFS_AC_SIZE; i++) 918 if (AFFS_I(inode)->i_ac[i].ext >= ext) 919 AFFS_I(inode)->i_ac[i].ext = 0; 920 } 921 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension); 922 923 blkcnt = AFFS_I(inode)->i_blkcnt; 924 i = 0; 925 blk = last_blk; 926 if (inode->i_size) { 927 i = last_blk % AFFS_SB(sb)->s_hashsize + 1; 928 blk++; 929 } else 930 AFFS_HEAD(ext_bh)->first_data = 0; 931 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(i); 932 size = AFFS_SB(sb)->s_hashsize; 933 if (size > blkcnt - blk + i) 934 size = blkcnt - blk + i; 935 for (; i < size; i++, blk++) { 936 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i))); 937 AFFS_BLOCK(sb, ext_bh, i) = 0; 938 } 939 AFFS_TAIL(sb, ext_bh)->extension = 0; 940 affs_fix_checksum(sb, ext_bh); 941 mark_buffer_dirty_inode(ext_bh, inode); 942 affs_brelse(ext_bh); 943 944 if (inode->i_size) { 945 AFFS_I(inode)->i_blkcnt = last_blk + 1; 946 AFFS_I(inode)->i_extcnt = ext + 1; 947 if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_OFS)) { 948 struct buffer_head *bh = affs_bread_ino(inode, last_blk, 0); 949 u32 tmp; 950 if (IS_ERR(bh)) { 951 affs_warning(sb, "truncate", 952 "unexpected read error for last block %u (%ld)", 953 ext, PTR_ERR(bh)); 954 return; 955 } 956 tmp = be32_to_cpu(AFFS_DATA_HEAD(bh)->next); 957 AFFS_DATA_HEAD(bh)->next = 0; 958 affs_adjust_checksum(bh, -tmp); 959 affs_brelse(bh); 960 } 961 } else { 962 AFFS_I(inode)->i_blkcnt = 0; 963 AFFS_I(inode)->i_extcnt = 1; 964 } 965 AFFS_I(inode)->mmu_private = inode->i_size; 966 // unlock cache 967 968 while (ext_key) { 969 ext_bh = affs_bread(sb, ext_key); 970 size = AFFS_SB(sb)->s_hashsize; 971 if (size > blkcnt - blk) 972 size = blkcnt - blk; 973 for (i = 0; i < size; i++, blk++) 974 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i))); 975 affs_free_block(sb, ext_key); 976 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension); 977 affs_brelse(ext_bh); 978 } 979 affs_free_prealloc(inode); 980} 981 982int affs_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync) 983{ 984 struct inode *inode = filp->f_mapping->host; 985 int ret, err; 986 987 err = file_write_and_wait_range(filp, start, end); 988 if (err) 989 return err; 990 991 inode_lock(inode); 992 ret = write_inode_now(inode, 0); 993 err = sync_blockdev(inode->i_sb->s_bdev); 994 if (!ret) 995 ret = err; 996 inode_unlock(inode); 997 return ret; 998} 999const struct file_operations affs_file_operations = { 1000 .llseek = generic_file_llseek, 1001 .read_iter = generic_file_read_iter, 1002 .write_iter = generic_file_write_iter, 1003 .mmap = generic_file_mmap, 1004 .open = affs_file_open, 1005 .release = affs_file_release, 1006 .fsync = affs_file_fsync, 1007 .splice_read = filemap_splice_read, 1008}; 1009 1010const struct inode_operations affs_file_inode_operations = { 1011 .setattr = affs_notify_change, 1012}; 1013