1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/fs/affs/file.c 4 * 5 * (c) 1996 Hans-Joachim Widmaier - Rewritten 6 * 7 * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem. 8 * 9 * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem. 10 * 11 * (C) 1991 Linus Torvalds - minix filesystem 12 * 13 * affs regular file handling primitives 14 */ 15 16 #include <linux/uio.h> 17 #include <linux/blkdev.h> 18 #include <linux/mpage.h> 19 #include "affs.h" 20 21 static struct buffer_head *affs_get_extblock_slow(struct inode *inode, u32 ext); 22 23 static int 24 affs_file_open(struct inode *inode, struct file *filp) 25 { 26 pr_debug("open(%lu,%d)\n", 27 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt)); 28 atomic_inc(&AFFS_I(inode)->i_opencnt); 29 return 0; 30 } 31 32 static int 33 affs_file_release(struct inode *inode, struct file *filp) 34 { 35 pr_debug("release(%lu, %d)\n", 36 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt)); 37 38 if (atomic_dec_and_test(&AFFS_I(inode)->i_opencnt)) { 39 inode_lock(inode); 40 if (inode->i_size != AFFS_I(inode)->mmu_private) 41 affs_truncate(inode); 42 affs_free_prealloc(inode); 43 inode_unlock(inode); 44 } 45 46 return 0; 47 } 48 49 static int 50 affs_grow_extcache(struct inode *inode, u32 lc_idx) 51 { 52 struct super_block *sb = inode->i_sb; 53 struct buffer_head *bh; 54 u32 lc_max; 55 int i, j, key; 56 57 if (!AFFS_I(inode)->i_lc) { 58 char *ptr = (char *)get_zeroed_page(GFP_NOFS); 59 if (!ptr) 60 return -ENOMEM; 61 AFFS_I(inode)->i_lc = (u32 *)ptr; 62 AFFS_I(inode)->i_ac = (struct affs_ext_key *)(ptr + AFFS_CACHE_SIZE / 2); 63 } 64 65 lc_max = AFFS_LC_SIZE << AFFS_I(inode)->i_lc_shift; 66 67 if (AFFS_I(inode)->i_extcnt > lc_max) { 68 u32 lc_shift, lc_mask, tmp, off; 69 70 /* need to recalculate linear cache, start from old size */ 71 lc_shift = AFFS_I(inode)->i_lc_shift; 72 tmp = (AFFS_I(inode)->i_extcnt / AFFS_LC_SIZE) >> lc_shift; 73 for (; tmp; tmp >>= 1) 74 lc_shift++; 75 lc_mask = (1 << lc_shift) - 1; 76 77 /* fix idx and old size to new shift */ 78 lc_idx >>= (lc_shift - AFFS_I(inode)->i_lc_shift); 79 AFFS_I(inode)->i_lc_size >>= (lc_shift - AFFS_I(inode)->i_lc_shift); 80 81 /* first shrink old cache to make more space */ 82 off = 1 << (lc_shift - AFFS_I(inode)->i_lc_shift); 83 for (i = 1, j = off; j < AFFS_LC_SIZE; i++, j += off) 84 AFFS_I(inode)->i_ac[i] = AFFS_I(inode)->i_ac[j]; 85 86 AFFS_I(inode)->i_lc_shift = lc_shift; 87 AFFS_I(inode)->i_lc_mask = lc_mask; 88 } 89 90 /* fill cache to the needed index */ 91 i = AFFS_I(inode)->i_lc_size; 92 AFFS_I(inode)->i_lc_size = lc_idx + 1; 93 for (; i <= lc_idx; i++) { 94 if (!i) { 95 AFFS_I(inode)->i_lc[0] = inode->i_ino; 96 continue; 97 } 98 key = AFFS_I(inode)->i_lc[i - 1]; 99 j = AFFS_I(inode)->i_lc_mask + 1; 100 // unlock cache 101 for (; j > 0; j--) { 102 bh = affs_bread(sb, key); 103 if (!bh) 104 goto err; 105 key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); 106 affs_brelse(bh); 107 } 108 // lock cache 109 AFFS_I(inode)->i_lc[i] = key; 110 } 111 112 return 0; 113 114 err: 115 // lock cache 116 return -EIO; 117 } 118 119 static struct buffer_head * 120 affs_alloc_extblock(struct inode *inode, struct buffer_head *bh, u32 ext) 121 { 122 struct super_block *sb = inode->i_sb; 123 struct buffer_head *new_bh; 124 u32 blocknr, tmp; 125 126 blocknr = affs_alloc_block(inode, bh->b_blocknr); 127 if (!blocknr) 128 return ERR_PTR(-ENOSPC); 129 130 new_bh = affs_getzeroblk(sb, blocknr); 131 if (!new_bh) { 132 affs_free_block(sb, blocknr); 133 return ERR_PTR(-EIO); 134 } 135 136 AFFS_HEAD(new_bh)->ptype = cpu_to_be32(T_LIST); 137 AFFS_HEAD(new_bh)->key = cpu_to_be32(blocknr); 138 AFFS_TAIL(sb, new_bh)->stype = cpu_to_be32(ST_FILE); 139 AFFS_TAIL(sb, new_bh)->parent = cpu_to_be32(inode->i_ino); 140 affs_fix_checksum(sb, new_bh); 141 142 mark_buffer_dirty_inode(new_bh, inode); 143 144 tmp = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); 145 if (tmp) 146 affs_warning(sb, "alloc_ext", "previous extension set (%x)", tmp); 147 AFFS_TAIL(sb, bh)->extension = cpu_to_be32(blocknr); 148 affs_adjust_checksum(bh, blocknr - tmp); 149 mark_buffer_dirty_inode(bh, inode); 150 151 AFFS_I(inode)->i_extcnt++; 152 mark_inode_dirty(inode); 153 154 return new_bh; 155 } 156 157 static inline struct buffer_head * 158 affs_get_extblock(struct inode *inode, u32 ext) 159 { 160 /* inline the simplest case: same extended block as last time */ 161 struct buffer_head *bh = AFFS_I(inode)->i_ext_bh; 162 if (ext == AFFS_I(inode)->i_ext_last) 163 get_bh(bh); 164 else 165 /* we have to do more (not inlined) */ 166 bh = affs_get_extblock_slow(inode, ext); 167 168 return bh; 169 } 170 171 static struct buffer_head * 172 affs_get_extblock_slow(struct inode *inode, u32 ext) 173 { 174 struct super_block *sb = inode->i_sb; 175 struct buffer_head *bh; 176 u32 ext_key; 177 u32 lc_idx, lc_off, ac_idx; 178 u32 tmp, idx; 179 180 if (ext == AFFS_I(inode)->i_ext_last + 1) { 181 /* read the next extended block from the current one */ 182 bh = AFFS_I(inode)->i_ext_bh; 183 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); 184 if (ext < AFFS_I(inode)->i_extcnt) 185 goto read_ext; 186 BUG_ON(ext > AFFS_I(inode)->i_extcnt); 187 bh = affs_alloc_extblock(inode, bh, ext); 188 if (IS_ERR(bh)) 189 return bh; 190 goto store_ext; 191 } 192 193 if (ext == 0) { 194 /* we seek back to the file header block */ 195 ext_key = inode->i_ino; 196 goto read_ext; 197 } 198 199 if (ext >= AFFS_I(inode)->i_extcnt) { 200 struct buffer_head *prev_bh; 201 202 /* allocate a new extended block */ 203 BUG_ON(ext > AFFS_I(inode)->i_extcnt); 204 205 /* get previous extended block */ 206 prev_bh = affs_get_extblock(inode, ext - 1); 207 if (IS_ERR(prev_bh)) 208 return prev_bh; 209 bh = affs_alloc_extblock(inode, prev_bh, ext); 210 affs_brelse(prev_bh); 211 if (IS_ERR(bh)) 212 return bh; 213 goto store_ext; 214 } 215 216 again: 217 /* check if there is an extended cache and whether it's large enough */ 218 lc_idx = ext >> AFFS_I(inode)->i_lc_shift; 219 lc_off = ext & AFFS_I(inode)->i_lc_mask; 220 221 if (lc_idx >= AFFS_I(inode)->i_lc_size) { 222 int err; 223 224 err = affs_grow_extcache(inode, lc_idx); 225 if (err) 226 return ERR_PTR(err); 227 goto again; 228 } 229 230 /* every n'th key we find in the linear cache */ 231 if (!lc_off) { 232 ext_key = AFFS_I(inode)->i_lc[lc_idx]; 233 goto read_ext; 234 } 235 236 /* maybe it's still in the associative cache */ 237 ac_idx = (ext - lc_idx - 1) & AFFS_AC_MASK; 238 if (AFFS_I(inode)->i_ac[ac_idx].ext == ext) { 239 ext_key = AFFS_I(inode)->i_ac[ac_idx].key; 240 goto read_ext; 241 } 242 243 /* try to find one of the previous extended blocks */ 244 tmp = ext; 245 idx = ac_idx; 246 while (--tmp, --lc_off > 0) { 247 idx = (idx - 1) & AFFS_AC_MASK; 248 if (AFFS_I(inode)->i_ac[idx].ext == tmp) { 249 ext_key = AFFS_I(inode)->i_ac[idx].key; 250 goto find_ext; 251 } 252 } 253 254 /* fall back to the linear cache */ 255 ext_key = AFFS_I(inode)->i_lc[lc_idx]; 256 find_ext: 257 /* read all extended blocks until we find the one we need */ 258 //unlock cache 259 do { 260 bh = affs_bread(sb, ext_key); 261 if (!bh) 262 goto err_bread; 263 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); 264 affs_brelse(bh); 265 tmp++; 266 } while (tmp < ext); 267 //lock cache 268 269 /* store it in the associative cache */ 270 // recalculate ac_idx? 271 AFFS_I(inode)->i_ac[ac_idx].ext = ext; 272 AFFS_I(inode)->i_ac[ac_idx].key = ext_key; 273 274 read_ext: 275 /* finally read the right extended block */ 276 //unlock cache 277 bh = affs_bread(sb, ext_key); 278 if (!bh) 279 goto err_bread; 280 //lock cache 281 282 store_ext: 283 /* release old cached extended block and store the new one */ 284 affs_brelse(AFFS_I(inode)->i_ext_bh); 285 AFFS_I(inode)->i_ext_last = ext; 286 AFFS_I(inode)->i_ext_bh = bh; 287 get_bh(bh); 288 289 return bh; 290 291 err_bread: 292 affs_brelse(bh); 293 return ERR_PTR(-EIO); 294 } 295 296 static int 297 affs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh_result, int create) 298 { 299 struct super_block *sb = inode->i_sb; 300 struct buffer_head *ext_bh; 301 u32 ext; 302 303 pr_debug("%s(%lu, %llu)\n", __func__, inode->i_ino, 304 (unsigned long long)block); 305 306 BUG_ON(block > (sector_t)0x7fffffffUL); 307 308 if (block >= AFFS_I(inode)->i_blkcnt) { 309 if (block > AFFS_I(inode)->i_blkcnt || !create) 310 goto err_big; 311 } else 312 create = 0; 313 314 //lock cache 315 affs_lock_ext(inode); 316 317 ext = (u32)block / AFFS_SB(sb)->s_hashsize; 318 block -= ext * AFFS_SB(sb)->s_hashsize; 319 ext_bh = affs_get_extblock(inode, ext); 320 if (IS_ERR(ext_bh)) 321 goto err_ext; 322 map_bh(bh_result, sb, (sector_t)be32_to_cpu(AFFS_BLOCK(sb, ext_bh, block))); 323 324 if (create) { 325 u32 blocknr = affs_alloc_block(inode, ext_bh->b_blocknr); 326 if (!blocknr) 327 goto err_alloc; 328 set_buffer_new(bh_result); 329 AFFS_I(inode)->mmu_private += AFFS_SB(sb)->s_data_blksize; 330 AFFS_I(inode)->i_blkcnt++; 331 332 /* store new block */ 333 if (bh_result->b_blocknr) 334 affs_warning(sb, "get_block", 335 "block already set (%llx)", 336 (unsigned long long)bh_result->b_blocknr); 337 AFFS_BLOCK(sb, ext_bh, block) = cpu_to_be32(blocknr); 338 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(block + 1); 339 affs_adjust_checksum(ext_bh, blocknr - bh_result->b_blocknr + 1); 340 bh_result->b_blocknr = blocknr; 341 342 if (!block) { 343 /* insert first block into header block */ 344 u32 tmp = be32_to_cpu(AFFS_HEAD(ext_bh)->first_data); 345 if (tmp) 346 affs_warning(sb, "get_block", "first block already set (%d)", tmp); 347 AFFS_HEAD(ext_bh)->first_data = cpu_to_be32(blocknr); 348 affs_adjust_checksum(ext_bh, blocknr - tmp); 349 } 350 } 351 352 affs_brelse(ext_bh); 353 //unlock cache 354 affs_unlock_ext(inode); 355 return 0; 356 357 err_big: 358 affs_error(inode->i_sb, "get_block", "strange block request %llu", 359 (unsigned long long)block); 360 return -EIO; 361 err_ext: 362 // unlock cache 363 affs_unlock_ext(inode); 364 return PTR_ERR(ext_bh); 365 err_alloc: 366 brelse(ext_bh); 367 clear_buffer_mapped(bh_result); 368 bh_result->b_bdev = NULL; 369 // unlock cache 370 affs_unlock_ext(inode); 371 return -ENOSPC; 372 } 373 374 static int affs_writepages(struct address_space *mapping, 375 struct writeback_control *wbc) 376 { 377 return mpage_writepages(mapping, wbc, affs_get_block); 378 } 379 380 static int affs_read_folio(struct file *file, struct folio *folio) 381 { 382 return block_read_full_folio(folio, affs_get_block); 383 } 384 385 static void affs_write_failed(struct address_space *mapping, loff_t to) 386 { 387 struct inode *inode = mapping->host; 388 389 if (to > inode->i_size) { 390 truncate_pagecache(inode, inode->i_size); 391 affs_truncate(inode); 392 } 393 } 394 395 static ssize_t 396 affs_direct_IO(struct kiocb *iocb, struct iov_iter *iter) 397 { 398 struct file *file = iocb->ki_filp; 399 struct address_space *mapping = file->f_mapping; 400 struct inode *inode = mapping->host; 401 size_t count = iov_iter_count(iter); 402 loff_t offset = iocb->ki_pos; 403 ssize_t ret; 404 405 if (iov_iter_rw(iter) == WRITE) { 406 loff_t size = offset + count; 407 408 if (AFFS_I(inode)->mmu_private < size) 409 return 0; 410 } 411 412 ret = blockdev_direct_IO(iocb, inode, iter, affs_get_block); 413 if (ret < 0 && iov_iter_rw(iter) == WRITE) 414 affs_write_failed(mapping, offset + count); 415 return ret; 416 } 417 418 static 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 } 433 434 static 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 } 451 452 static sector_t _affs_bmap(struct address_space *mapping, sector_t block) 453 { 454 return generic_block_bmap(mapping,block,affs_get_block); 455 } 456 457 const 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 }; 468 469 static inline struct buffer_head * 470 affs_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 } 487 488 static inline struct buffer_head * 489 affs_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 } 506 507 static inline struct buffer_head * 508 affs_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 } 525 526 static int 527 affs_do_readpage_ofs(struct page *page, unsigned to, int create) 528 { 529 struct inode *inode = page->mapping->host; 530 struct super_block *sb = inode->i_sb; 531 struct buffer_head *bh; 532 unsigned pos = 0; 533 u32 bidx, boff, bsize; 534 u32 tmp; 535 536 pr_debug("%s(%lu, %ld, 0, %d)\n", __func__, inode->i_ino, 537 page->index, to); 538 BUG_ON(to > PAGE_SIZE); 539 bsize = AFFS_SB(sb)->s_data_blksize; 540 tmp = page->index << PAGE_SHIFT; 541 bidx = tmp / bsize; 542 boff = tmp % bsize; 543 544 while (pos < to) { 545 bh = affs_bread_ino(inode, bidx, create); 546 if (IS_ERR(bh)) 547 return PTR_ERR(bh); 548 tmp = min(bsize - boff, to - pos); 549 BUG_ON(pos + tmp > to || tmp > bsize); 550 memcpy_to_page(page, pos, AFFS_DATA(bh) + boff, tmp); 551 affs_brelse(bh); 552 bidx++; 553 pos += tmp; 554 boff = 0; 555 } 556 return 0; 557 } 558 559 static int 560 affs_extent_file_ofs(struct inode *inode, u32 newsize) 561 { 562 struct super_block *sb = inode->i_sb; 563 struct buffer_head *bh, *prev_bh; 564 u32 bidx, boff; 565 u32 size, bsize; 566 u32 tmp; 567 568 pr_debug("%s(%lu, %d)\n", __func__, inode->i_ino, newsize); 569 bsize = AFFS_SB(sb)->s_data_blksize; 570 bh = NULL; 571 size = AFFS_I(inode)->mmu_private; 572 bidx = size / bsize; 573 boff = size % bsize; 574 if (boff) { 575 bh = affs_bread_ino(inode, bidx, 0); 576 if (IS_ERR(bh)) 577 return PTR_ERR(bh); 578 tmp = min(bsize - boff, newsize - size); 579 BUG_ON(boff + tmp > bsize || tmp > bsize); 580 memset(AFFS_DATA(bh) + boff, 0, tmp); 581 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp); 582 affs_fix_checksum(sb, bh); 583 mark_buffer_dirty_inode(bh, inode); 584 size += tmp; 585 bidx++; 586 } else if (bidx) { 587 bh = affs_bread_ino(inode, bidx - 1, 0); 588 if (IS_ERR(bh)) 589 return PTR_ERR(bh); 590 } 591 592 while (size < newsize) { 593 prev_bh = bh; 594 bh = affs_getzeroblk_ino(inode, bidx); 595 if (IS_ERR(bh)) 596 goto out; 597 tmp = min(bsize, newsize - size); 598 BUG_ON(tmp > bsize); 599 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); 600 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); 601 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); 602 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); 603 affs_fix_checksum(sb, bh); 604 bh->b_state &= ~(1UL << BH_New); 605 mark_buffer_dirty_inode(bh, inode); 606 if (prev_bh) { 607 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); 608 609 if (tmp_next) 610 affs_warning(sb, "extent_file_ofs", 611 "next block already set for %d (%d)", 612 bidx, tmp_next); 613 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); 614 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next); 615 mark_buffer_dirty_inode(prev_bh, inode); 616 affs_brelse(prev_bh); 617 } 618 size += bsize; 619 bidx++; 620 } 621 affs_brelse(bh); 622 inode->i_size = AFFS_I(inode)->mmu_private = newsize; 623 return 0; 624 625 out: 626 inode->i_size = AFFS_I(inode)->mmu_private = newsize; 627 return PTR_ERR(bh); 628 } 629 630 static int 631 affs_read_folio_ofs(struct file *file, struct folio *folio) 632 { 633 struct page *page = &folio->page; 634 struct inode *inode = page->mapping->host; 635 u32 to; 636 int err; 637 638 pr_debug("%s(%lu, %ld)\n", __func__, inode->i_ino, page->index); 639 to = PAGE_SIZE; 640 if (((page->index + 1) << PAGE_SHIFT) > inode->i_size) { 641 to = inode->i_size & ~PAGE_MASK; 642 memset(page_address(page) + to, 0, PAGE_SIZE - to); 643 } 644 645 err = affs_do_readpage_ofs(page, to, 0); 646 if (!err) 647 SetPageUptodate(page); 648 unlock_page(page); 649 return err; 650 } 651 652 static int affs_write_begin_ofs(struct file *file, struct address_space *mapping, 653 loff_t pos, unsigned len, 654 struct page **pagep, void **fsdata) 655 { 656 struct inode *inode = mapping->host; 657 struct page *page; 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 page = grab_cache_page_write_begin(mapping, index); 674 if (!page) 675 return -ENOMEM; 676 *pagep = page; 677 678 if (PageUptodate(page)) 679 return 0; 680 681 /* XXX: inefficient but safe in the face of short writes */ 682 err = affs_do_readpage_ofs(page, PAGE_SIZE, 1); 683 if (err) { 684 unlock_page(page); 685 put_page(page); 686 } 687 return err; 688 } 689 690 static int affs_write_end_ofs(struct file *file, struct address_space *mapping, 691 loff_t pos, unsigned len, unsigned copied, 692 struct page *page, void *fsdata) 693 { 694 struct inode *inode = mapping->host; 695 struct super_block *sb = inode->i_sb; 696 struct buffer_head *bh, *prev_bh; 697 char *data; 698 u32 bidx, boff, bsize; 699 unsigned from, to; 700 u32 tmp; 701 int written; 702 703 from = pos & (PAGE_SIZE - 1); 704 to = from + len; 705 /* 706 * XXX: not sure if this can handle short copies (len < copied), but 707 * we don't have to, because the page should always be uptodate here, 708 * due to write_begin. 709 */ 710 711 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos, 712 pos + len); 713 bsize = AFFS_SB(sb)->s_data_blksize; 714 data = page_address(page); 715 716 bh = NULL; 717 written = 0; 718 tmp = (page->index << PAGE_SHIFT) + from; 719 bidx = tmp / bsize; 720 boff = tmp % bsize; 721 if (boff) { 722 bh = affs_bread_ino(inode, bidx, 0); 723 if (IS_ERR(bh)) { 724 written = PTR_ERR(bh); 725 goto err_first_bh; 726 } 727 tmp = min(bsize - boff, to - from); 728 BUG_ON(boff + tmp > bsize || tmp > bsize); 729 memcpy(AFFS_DATA(bh) + boff, data + from, tmp); 730 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp); 731 affs_fix_checksum(sb, bh); 732 mark_buffer_dirty_inode(bh, inode); 733 written += tmp; 734 from += tmp; 735 bidx++; 736 } else if (bidx) { 737 bh = affs_bread_ino(inode, bidx - 1, 0); 738 if (IS_ERR(bh)) { 739 written = PTR_ERR(bh); 740 goto err_first_bh; 741 } 742 } 743 while (from + bsize <= to) { 744 prev_bh = bh; 745 bh = affs_getemptyblk_ino(inode, bidx); 746 if (IS_ERR(bh)) 747 goto err_bh; 748 memcpy(AFFS_DATA(bh), data + from, bsize); 749 if (buffer_new(bh)) { 750 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); 751 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); 752 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); 753 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(bsize); 754 AFFS_DATA_HEAD(bh)->next = 0; 755 bh->b_state &= ~(1UL << BH_New); 756 if (prev_bh) { 757 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); 758 759 if (tmp_next) 760 affs_warning(sb, "commit_write_ofs", 761 "next block already set for %d (%d)", 762 bidx, tmp_next); 763 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); 764 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next); 765 mark_buffer_dirty_inode(prev_bh, inode); 766 } 767 } 768 affs_brelse(prev_bh); 769 affs_fix_checksum(sb, bh); 770 mark_buffer_dirty_inode(bh, inode); 771 written += bsize; 772 from += bsize; 773 bidx++; 774 } 775 if (from < to) { 776 prev_bh = bh; 777 bh = affs_bread_ino(inode, bidx, 1); 778 if (IS_ERR(bh)) 779 goto err_bh; 780 tmp = min(bsize, to - from); 781 BUG_ON(tmp > bsize); 782 memcpy(AFFS_DATA(bh), data + from, tmp); 783 if (buffer_new(bh)) { 784 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); 785 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); 786 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); 787 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); 788 AFFS_DATA_HEAD(bh)->next = 0; 789 bh->b_state &= ~(1UL << BH_New); 790 if (prev_bh) { 791 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); 792 793 if (tmp_next) 794 affs_warning(sb, "commit_write_ofs", 795 "next block already set for %d (%d)", 796 bidx, tmp_next); 797 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); 798 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next); 799 mark_buffer_dirty_inode(prev_bh, inode); 800 } 801 } else if (be32_to_cpu(AFFS_DATA_HEAD(bh)->size) < tmp) 802 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); 803 affs_brelse(prev_bh); 804 affs_fix_checksum(sb, bh); 805 mark_buffer_dirty_inode(bh, inode); 806 written += tmp; 807 from += tmp; 808 bidx++; 809 } 810 SetPageUptodate(page); 811 812 done: 813 affs_brelse(bh); 814 tmp = (page->index << PAGE_SHIFT) + from; 815 if (tmp > inode->i_size) 816 inode->i_size = AFFS_I(inode)->mmu_private = tmp; 817 818 /* Clear Archived bit on file writes, as AmigaOS would do */ 819 if (AFFS_I(inode)->i_protect & FIBF_ARCHIVED) { 820 AFFS_I(inode)->i_protect &= ~FIBF_ARCHIVED; 821 mark_inode_dirty(inode); 822 } 823 824 err_first_bh: 825 unlock_page(page); 826 put_page(page); 827 828 return written; 829 830 err_bh: 831 bh = prev_bh; 832 if (!written) 833 written = PTR_ERR(bh); 834 goto done; 835 } 836 837 const struct address_space_operations affs_aops_ofs = { 838 .dirty_folio = block_dirty_folio, 839 .invalidate_folio = block_invalidate_folio, 840 .read_folio = affs_read_folio_ofs, 841 //.writepages = affs_writepages_ofs, 842 .write_begin = affs_write_begin_ofs, 843 .write_end = affs_write_end_ofs, 844 .migrate_folio = filemap_migrate_folio, 845 }; 846 847 /* Free any preallocated blocks. */ 848 849 void 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 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 = NULL; 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 } 982 983 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 = filemap_splice_read, 1009 }; 1010 1011 const struct inode_operations affs_file_inode_operations = { 1012 .setattr = affs_notify_change, 1013 }; 1014