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 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 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 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 * 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 * 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 * 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 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 } 372 373 static int affs_writepage(struct page *page, struct writeback_control *wbc) 374 { 375 return block_write_full_page(page, affs_get_block, wbc); 376 } 377 378 static int affs_readpage(struct file *file, struct page *page) 379 { 380 return block_read_full_page(page, affs_get_block); 381 } 382 383 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 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 } 415 416 static int affs_write_begin(struct file *file, struct address_space *mapping, 417 loff_t pos, unsigned len, unsigned flags, 418 struct page **pagep, void **fsdata) 419 { 420 int ret; 421 422 *pagep = NULL; 423 ret = cont_write_begin(file, mapping, pos, len, flags, 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 } 431 432 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 } 449 450 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 .readpage = affs_readpage, 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 * 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 * 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 * 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 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 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 632 affs_readpage_ofs(struct file *file, struct page *page) 633 { 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, unsigned flags, 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, flags); 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 .readpage = affs_readpage_ofs, 841 //.writepage = affs_writepage_ofs, 842 .write_begin = affs_write_begin_ofs, 843 .write_end = affs_write_end_ofs 844 }; 845 846 /* Free any preallocated blocks. */ 847 848 void 849 affs_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. */ 862 863 void 864 affs_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; 887 loff_t isize = inode->i_size; 888 int res; 889 890 res = mapping->a_ops->write_begin(NULL, mapping, isize, 0, 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 } 981 982 int 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 } 999 const 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 = generic_file_splice_read, 1008 }; 1009 1010 const struct inode_operations affs_file_inode_operations = { 1011 .setattr = affs_notify_change, 1012 }; 1013