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 .set_page_dirty = __set_page_dirty_buffers, 457 .readpage = affs_readpage, 458 .writepage = affs_writepage, 459 .write_begin = affs_write_begin, 460 .write_end = affs_write_end, 461 .direct_IO = affs_direct_IO, 462 .bmap = _affs_bmap 463 }; 464 465 static inline struct buffer_head * 466 affs_bread_ino(struct inode *inode, int block, int create) 467 { 468 struct buffer_head *bh, tmp_bh; 469 int err; 470 471 tmp_bh.b_state = 0; 472 err = affs_get_block(inode, block, &tmp_bh, create); 473 if (!err) { 474 bh = affs_bread(inode->i_sb, tmp_bh.b_blocknr); 475 if (bh) { 476 bh->b_state |= tmp_bh.b_state; 477 return bh; 478 } 479 err = -EIO; 480 } 481 return ERR_PTR(err); 482 } 483 484 static inline struct buffer_head * 485 affs_getzeroblk_ino(struct inode *inode, int block) 486 { 487 struct buffer_head *bh, tmp_bh; 488 int err; 489 490 tmp_bh.b_state = 0; 491 err = affs_get_block(inode, block, &tmp_bh, 1); 492 if (!err) { 493 bh = affs_getzeroblk(inode->i_sb, tmp_bh.b_blocknr); 494 if (bh) { 495 bh->b_state |= tmp_bh.b_state; 496 return bh; 497 } 498 err = -EIO; 499 } 500 return ERR_PTR(err); 501 } 502 503 static inline struct buffer_head * 504 affs_getemptyblk_ino(struct inode *inode, int block) 505 { 506 struct buffer_head *bh, tmp_bh; 507 int err; 508 509 tmp_bh.b_state = 0; 510 err = affs_get_block(inode, block, &tmp_bh, 1); 511 if (!err) { 512 bh = affs_getemptyblk(inode->i_sb, tmp_bh.b_blocknr); 513 if (bh) { 514 bh->b_state |= tmp_bh.b_state; 515 return bh; 516 } 517 err = -EIO; 518 } 519 return ERR_PTR(err); 520 } 521 522 static int 523 affs_do_readpage_ofs(struct page *page, unsigned to, int create) 524 { 525 struct inode *inode = page->mapping->host; 526 struct super_block *sb = inode->i_sb; 527 struct buffer_head *bh; 528 char *data; 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 data = kmap_atomic(page); 548 memcpy(data + pos, AFFS_DATA(bh) + boff, tmp); 549 kunmap_atomic(data); 550 affs_brelse(bh); 551 bidx++; 552 pos += tmp; 553 boff = 0; 554 } 555 flush_dcache_page(page); 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_readpage_ofs(struct file *file, struct page *page) 632 { 633 struct inode *inode = page->mapping->host; 634 u32 to; 635 int err; 636 637 pr_debug("%s(%lu, %ld)\n", __func__, inode->i_ino, page->index); 638 to = PAGE_SIZE; 639 if (((page->index + 1) << PAGE_SHIFT) > inode->i_size) { 640 to = inode->i_size & ~PAGE_MASK; 641 memset(page_address(page) + to, 0, PAGE_SIZE - to); 642 } 643 644 err = affs_do_readpage_ofs(page, to, 0); 645 if (!err) 646 SetPageUptodate(page); 647 unlock_page(page); 648 return err; 649 } 650 651 static int affs_write_begin_ofs(struct file *file, struct address_space *mapping, 652 loff_t pos, unsigned len, unsigned flags, 653 struct page **pagep, void **fsdata) 654 { 655 struct inode *inode = mapping->host; 656 struct page *page; 657 pgoff_t index; 658 int err = 0; 659 660 pr_debug("%s(%lu, %llu, %llu)\n", __func__, inode->i_ino, pos, 661 pos + len); 662 if (pos > AFFS_I(inode)->mmu_private) { 663 /* XXX: this probably leaves a too-big i_size in case of 664 * failure. Should really be updating i_size at write_end time 665 */ 666 err = affs_extent_file_ofs(inode, pos); 667 if (err) 668 return err; 669 } 670 671 index = pos >> PAGE_SHIFT; 672 page = grab_cache_page_write_begin(mapping, index, flags); 673 if (!page) 674 return -ENOMEM; 675 *pagep = page; 676 677 if (PageUptodate(page)) 678 return 0; 679 680 /* XXX: inefficient but safe in the face of short writes */ 681 err = affs_do_readpage_ofs(page, PAGE_SIZE, 1); 682 if (err) { 683 unlock_page(page); 684 put_page(page); 685 } 686 return err; 687 } 688 689 static int affs_write_end_ofs(struct file *file, struct address_space *mapping, 690 loff_t pos, unsigned len, unsigned copied, 691 struct page *page, void *fsdata) 692 { 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 page 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 = page_address(page); 714 715 bh = NULL; 716 written = 0; 717 tmp = (page->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 SetPageUptodate(page); 810 811 done: 812 affs_brelse(bh); 813 tmp = (page->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 } 822 823 err_first_bh: 824 unlock_page(page); 825 put_page(page); 826 827 return written; 828 829 err_bh: 830 bh = prev_bh; 831 if (!written) 832 written = PTR_ERR(bh); 833 goto done; 834 } 835 836 const struct address_space_operations affs_aops_ofs = { 837 .set_page_dirty = __set_page_dirty_buffers, 838 .readpage = affs_readpage_ofs, 839 //.writepage = affs_writepage_ofs, 840 .write_begin = affs_write_begin_ofs, 841 .write_end = affs_write_end_ofs 842 }; 843 844 /* Free any preallocated blocks. */ 845 846 void 847 affs_free_prealloc(struct inode *inode) 848 { 849 struct super_block *sb = inode->i_sb; 850 851 pr_debug("free_prealloc(ino=%lu)\n", inode->i_ino); 852 853 while (AFFS_I(inode)->i_pa_cnt) { 854 AFFS_I(inode)->i_pa_cnt--; 855 affs_free_block(sb, ++AFFS_I(inode)->i_lastalloc); 856 } 857 } 858 859 /* Truncate (or enlarge) a file to the requested size. */ 860 861 void 862 affs_truncate(struct inode *inode) 863 { 864 struct super_block *sb = inode->i_sb; 865 u32 ext, ext_key; 866 u32 last_blk, blkcnt, blk; 867 u32 size; 868 struct buffer_head *ext_bh; 869 int i; 870 871 pr_debug("truncate(inode=%lu, oldsize=%llu, newsize=%llu)\n", 872 inode->i_ino, AFFS_I(inode)->mmu_private, inode->i_size); 873 874 last_blk = 0; 875 ext = 0; 876 if (inode->i_size) { 877 last_blk = ((u32)inode->i_size - 1) / AFFS_SB(sb)->s_data_blksize; 878 ext = last_blk / AFFS_SB(sb)->s_hashsize; 879 } 880 881 if (inode->i_size > AFFS_I(inode)->mmu_private) { 882 struct address_space *mapping = inode->i_mapping; 883 struct page *page; 884 void *fsdata; 885 loff_t isize = inode->i_size; 886 int res; 887 888 res = mapping->a_ops->write_begin(NULL, mapping, isize, 0, 0, &page, &fsdata); 889 if (!res) 890 res = mapping->a_ops->write_end(NULL, mapping, isize, 0, 0, page, fsdata); 891 else 892 inode->i_size = AFFS_I(inode)->mmu_private; 893 mark_inode_dirty(inode); 894 return; 895 } else if (inode->i_size == AFFS_I(inode)->mmu_private) 896 return; 897 898 // lock cache 899 ext_bh = affs_get_extblock(inode, ext); 900 if (IS_ERR(ext_bh)) { 901 affs_warning(sb, "truncate", 902 "unexpected read error for ext block %u (%ld)", 903 ext, PTR_ERR(ext_bh)); 904 return; 905 } 906 if (AFFS_I(inode)->i_lc) { 907 /* clear linear cache */ 908 i = (ext + 1) >> AFFS_I(inode)->i_lc_shift; 909 if (AFFS_I(inode)->i_lc_size > i) { 910 AFFS_I(inode)->i_lc_size = i; 911 for (; i < AFFS_LC_SIZE; i++) 912 AFFS_I(inode)->i_lc[i] = 0; 913 } 914 /* clear associative cache */ 915 for (i = 0; i < AFFS_AC_SIZE; i++) 916 if (AFFS_I(inode)->i_ac[i].ext >= ext) 917 AFFS_I(inode)->i_ac[i].ext = 0; 918 } 919 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension); 920 921 blkcnt = AFFS_I(inode)->i_blkcnt; 922 i = 0; 923 blk = last_blk; 924 if (inode->i_size) { 925 i = last_blk % AFFS_SB(sb)->s_hashsize + 1; 926 blk++; 927 } else 928 AFFS_HEAD(ext_bh)->first_data = 0; 929 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(i); 930 size = AFFS_SB(sb)->s_hashsize; 931 if (size > blkcnt - blk + i) 932 size = blkcnt - blk + i; 933 for (; i < size; i++, blk++) { 934 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i))); 935 AFFS_BLOCK(sb, ext_bh, i) = 0; 936 } 937 AFFS_TAIL(sb, ext_bh)->extension = 0; 938 affs_fix_checksum(sb, ext_bh); 939 mark_buffer_dirty_inode(ext_bh, inode); 940 affs_brelse(ext_bh); 941 942 if (inode->i_size) { 943 AFFS_I(inode)->i_blkcnt = last_blk + 1; 944 AFFS_I(inode)->i_extcnt = ext + 1; 945 if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_OFS)) { 946 struct buffer_head *bh = affs_bread_ino(inode, last_blk, 0); 947 u32 tmp; 948 if (IS_ERR(bh)) { 949 affs_warning(sb, "truncate", 950 "unexpected read error for last block %u (%ld)", 951 ext, PTR_ERR(bh)); 952 return; 953 } 954 tmp = be32_to_cpu(AFFS_DATA_HEAD(bh)->next); 955 AFFS_DATA_HEAD(bh)->next = 0; 956 affs_adjust_checksum(bh, -tmp); 957 affs_brelse(bh); 958 } 959 } else { 960 AFFS_I(inode)->i_blkcnt = 0; 961 AFFS_I(inode)->i_extcnt = 1; 962 } 963 AFFS_I(inode)->mmu_private = inode->i_size; 964 // unlock cache 965 966 while (ext_key) { 967 ext_bh = affs_bread(sb, ext_key); 968 size = AFFS_SB(sb)->s_hashsize; 969 if (size > blkcnt - blk) 970 size = blkcnt - blk; 971 for (i = 0; i < size; i++, blk++) 972 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i))); 973 affs_free_block(sb, ext_key); 974 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension); 975 affs_brelse(ext_bh); 976 } 977 affs_free_prealloc(inode); 978 } 979 980 int affs_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync) 981 { 982 struct inode *inode = filp->f_mapping->host; 983 int ret, err; 984 985 err = file_write_and_wait_range(filp, start, end); 986 if (err) 987 return err; 988 989 inode_lock(inode); 990 ret = write_inode_now(inode, 0); 991 err = sync_blockdev(inode->i_sb->s_bdev); 992 if (!ret) 993 ret = err; 994 inode_unlock(inode); 995 return ret; 996 } 997 const struct file_operations affs_file_operations = { 998 .llseek = generic_file_llseek, 999 .read_iter = generic_file_read_iter, 1000 .write_iter = generic_file_write_iter, 1001 .mmap = generic_file_mmap, 1002 .open = affs_file_open, 1003 .release = affs_file_release, 1004 .fsync = affs_file_fsync, 1005 .splice_read = generic_file_splice_read, 1006 }; 1007 1008 const struct inode_operations affs_file_inode_operations = { 1009 .setattr = affs_notify_change, 1010 }; 1011