1 /* 2 * linux/fs/affs/file.c 3 * 4 * (c) 1996 Hans-Joachim Widmaier - Rewritten 5 * 6 * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem. 7 * 8 * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem. 9 * 10 * (C) 1991 Linus Torvalds - minix filesystem 11 * 12 * affs regular file handling primitives 13 */ 14 15 #include <linux/aio.h> 16 #include "affs.h" 17 18 static struct buffer_head *affs_get_extblock_slow(struct inode *inode, u32 ext); 19 20 static int 21 affs_file_open(struct inode *inode, struct file *filp) 22 { 23 pr_debug("open(%lu,%d)\n", 24 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt)); 25 atomic_inc(&AFFS_I(inode)->i_opencnt); 26 return 0; 27 } 28 29 static int 30 affs_file_release(struct inode *inode, struct file *filp) 31 { 32 pr_debug("release(%lu, %d)\n", 33 inode->i_ino, atomic_read(&AFFS_I(inode)->i_opencnt)); 34 35 if (atomic_dec_and_test(&AFFS_I(inode)->i_opencnt)) { 36 mutex_lock(&inode->i_mutex); 37 if (inode->i_size != AFFS_I(inode)->mmu_private) 38 affs_truncate(inode); 39 affs_free_prealloc(inode); 40 mutex_unlock(&inode->i_mutex); 41 } 42 43 return 0; 44 } 45 46 static int 47 affs_grow_extcache(struct inode *inode, u32 lc_idx) 48 { 49 struct super_block *sb = inode->i_sb; 50 struct buffer_head *bh; 51 u32 lc_max; 52 int i, j, key; 53 54 if (!AFFS_I(inode)->i_lc) { 55 char *ptr = (char *)get_zeroed_page(GFP_NOFS); 56 if (!ptr) 57 return -ENOMEM; 58 AFFS_I(inode)->i_lc = (u32 *)ptr; 59 AFFS_I(inode)->i_ac = (struct affs_ext_key *)(ptr + AFFS_CACHE_SIZE / 2); 60 } 61 62 lc_max = AFFS_LC_SIZE << AFFS_I(inode)->i_lc_shift; 63 64 if (AFFS_I(inode)->i_extcnt > lc_max) { 65 u32 lc_shift, lc_mask, tmp, off; 66 67 /* need to recalculate linear cache, start from old size */ 68 lc_shift = AFFS_I(inode)->i_lc_shift; 69 tmp = (AFFS_I(inode)->i_extcnt / AFFS_LC_SIZE) >> lc_shift; 70 for (; tmp; tmp >>= 1) 71 lc_shift++; 72 lc_mask = (1 << lc_shift) - 1; 73 74 /* fix idx and old size to new shift */ 75 lc_idx >>= (lc_shift - AFFS_I(inode)->i_lc_shift); 76 AFFS_I(inode)->i_lc_size >>= (lc_shift - AFFS_I(inode)->i_lc_shift); 77 78 /* first shrink old cache to make more space */ 79 off = 1 << (lc_shift - AFFS_I(inode)->i_lc_shift); 80 for (i = 1, j = off; j < AFFS_LC_SIZE; i++, j += off) 81 AFFS_I(inode)->i_ac[i] = AFFS_I(inode)->i_ac[j]; 82 83 AFFS_I(inode)->i_lc_shift = lc_shift; 84 AFFS_I(inode)->i_lc_mask = lc_mask; 85 } 86 87 /* fill cache to the needed index */ 88 i = AFFS_I(inode)->i_lc_size; 89 AFFS_I(inode)->i_lc_size = lc_idx + 1; 90 for (; i <= lc_idx; i++) { 91 if (!i) { 92 AFFS_I(inode)->i_lc[0] = inode->i_ino; 93 continue; 94 } 95 key = AFFS_I(inode)->i_lc[i - 1]; 96 j = AFFS_I(inode)->i_lc_mask + 1; 97 // unlock cache 98 for (; j > 0; j--) { 99 bh = affs_bread(sb, key); 100 if (!bh) 101 goto err; 102 key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); 103 affs_brelse(bh); 104 } 105 // lock cache 106 AFFS_I(inode)->i_lc[i] = key; 107 } 108 109 return 0; 110 111 err: 112 // lock cache 113 return -EIO; 114 } 115 116 static struct buffer_head * 117 affs_alloc_extblock(struct inode *inode, struct buffer_head *bh, u32 ext) 118 { 119 struct super_block *sb = inode->i_sb; 120 struct buffer_head *new_bh; 121 u32 blocknr, tmp; 122 123 blocknr = affs_alloc_block(inode, bh->b_blocknr); 124 if (!blocknr) 125 return ERR_PTR(-ENOSPC); 126 127 new_bh = affs_getzeroblk(sb, blocknr); 128 if (!new_bh) { 129 affs_free_block(sb, blocknr); 130 return ERR_PTR(-EIO); 131 } 132 133 AFFS_HEAD(new_bh)->ptype = cpu_to_be32(T_LIST); 134 AFFS_HEAD(new_bh)->key = cpu_to_be32(blocknr); 135 AFFS_TAIL(sb, new_bh)->stype = cpu_to_be32(ST_FILE); 136 AFFS_TAIL(sb, new_bh)->parent = cpu_to_be32(inode->i_ino); 137 affs_fix_checksum(sb, new_bh); 138 139 mark_buffer_dirty_inode(new_bh, inode); 140 141 tmp = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); 142 if (tmp) 143 affs_warning(sb, "alloc_ext", "previous extension set (%x)", tmp); 144 AFFS_TAIL(sb, bh)->extension = cpu_to_be32(blocknr); 145 affs_adjust_checksum(bh, blocknr - tmp); 146 mark_buffer_dirty_inode(bh, inode); 147 148 AFFS_I(inode)->i_extcnt++; 149 mark_inode_dirty(inode); 150 151 return new_bh; 152 } 153 154 static inline struct buffer_head * 155 affs_get_extblock(struct inode *inode, u32 ext) 156 { 157 /* inline the simplest case: same extended block as last time */ 158 struct buffer_head *bh = AFFS_I(inode)->i_ext_bh; 159 if (ext == AFFS_I(inode)->i_ext_last) 160 get_bh(bh); 161 else 162 /* we have to do more (not inlined) */ 163 bh = affs_get_extblock_slow(inode, ext); 164 165 return bh; 166 } 167 168 static struct buffer_head * 169 affs_get_extblock_slow(struct inode *inode, u32 ext) 170 { 171 struct super_block *sb = inode->i_sb; 172 struct buffer_head *bh; 173 u32 ext_key; 174 u32 lc_idx, lc_off, ac_idx; 175 u32 tmp, idx; 176 177 if (ext == AFFS_I(inode)->i_ext_last + 1) { 178 /* read the next extended block from the current one */ 179 bh = AFFS_I(inode)->i_ext_bh; 180 ext_key = be32_to_cpu(AFFS_TAIL(sb, bh)->extension); 181 if (ext < AFFS_I(inode)->i_extcnt) 182 goto read_ext; 183 if (ext > AFFS_I(inode)->i_extcnt) 184 BUG(); 185 bh = affs_alloc_extblock(inode, bh, ext); 186 if (IS_ERR(bh)) 187 return bh; 188 goto store_ext; 189 } 190 191 if (ext == 0) { 192 /* we seek back to the file header block */ 193 ext_key = inode->i_ino; 194 goto read_ext; 195 } 196 197 if (ext >= AFFS_I(inode)->i_extcnt) { 198 struct buffer_head *prev_bh; 199 200 /* allocate a new extended block */ 201 if (ext > AFFS_I(inode)->i_extcnt) 202 BUG(); 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(%u, %lu)\n", 303 __func__, (u32)inode->i_ino, (unsigned 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", "block already set (%lx)", 334 (unsigned long)bh_result->b_blocknr); 335 AFFS_BLOCK(sb, ext_bh, block) = cpu_to_be32(blocknr); 336 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(block + 1); 337 affs_adjust_checksum(ext_bh, blocknr - bh_result->b_blocknr + 1); 338 bh_result->b_blocknr = blocknr; 339 340 if (!block) { 341 /* insert first block into header block */ 342 u32 tmp = be32_to_cpu(AFFS_HEAD(ext_bh)->first_data); 343 if (tmp) 344 affs_warning(sb, "get_block", "first block already set (%d)", tmp); 345 AFFS_HEAD(ext_bh)->first_data = cpu_to_be32(blocknr); 346 affs_adjust_checksum(ext_bh, blocknr - tmp); 347 } 348 } 349 350 affs_brelse(ext_bh); 351 //unlock cache 352 affs_unlock_ext(inode); 353 return 0; 354 355 err_big: 356 affs_error(inode->i_sb, "get_block", "strange block request %d", 357 (int)block); 358 return -EIO; 359 err_ext: 360 // unlock cache 361 affs_unlock_ext(inode); 362 return PTR_ERR(ext_bh); 363 err_alloc: 364 brelse(ext_bh); 365 clear_buffer_mapped(bh_result); 366 bh_result->b_bdev = NULL; 367 // unlock cache 368 affs_unlock_ext(inode); 369 return -ENOSPC; 370 } 371 372 static int affs_writepage(struct page *page, struct writeback_control *wbc) 373 { 374 return block_write_full_page(page, affs_get_block, wbc); 375 } 376 377 static int affs_readpage(struct file *file, struct page *page) 378 { 379 return block_read_full_page(page, affs_get_block); 380 } 381 382 static void affs_write_failed(struct address_space *mapping, loff_t to) 383 { 384 struct inode *inode = mapping->host; 385 386 if (to > inode->i_size) { 387 truncate_pagecache(inode, inode->i_size); 388 affs_truncate(inode); 389 } 390 } 391 392 static ssize_t 393 affs_direct_IO(int rw, struct kiocb *iocb, struct iov_iter *iter, 394 loff_t offset) 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 ssize_t ret; 401 402 ret = blockdev_direct_IO(rw, iocb, inode, iter, offset, affs_get_block); 403 if (ret < 0 && (rw & WRITE)) 404 affs_write_failed(mapping, offset + count); 405 return ret; 406 } 407 408 static int affs_write_begin(struct file *file, struct address_space *mapping, 409 loff_t pos, unsigned len, unsigned flags, 410 struct page **pagep, void **fsdata) 411 { 412 int ret; 413 414 *pagep = NULL; 415 ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata, 416 affs_get_block, 417 &AFFS_I(mapping->host)->mmu_private); 418 if (unlikely(ret)) 419 affs_write_failed(mapping, pos + len); 420 421 return ret; 422 } 423 424 static sector_t _affs_bmap(struct address_space *mapping, sector_t block) 425 { 426 return generic_block_bmap(mapping,block,affs_get_block); 427 } 428 429 const struct address_space_operations affs_aops = { 430 .readpage = affs_readpage, 431 .writepage = affs_writepage, 432 .write_begin = affs_write_begin, 433 .write_end = generic_write_end, 434 .direct_IO = affs_direct_IO, 435 .bmap = _affs_bmap 436 }; 437 438 static inline struct buffer_head * 439 affs_bread_ino(struct inode *inode, int block, int create) 440 { 441 struct buffer_head *bh, tmp_bh; 442 int err; 443 444 tmp_bh.b_state = 0; 445 err = affs_get_block(inode, block, &tmp_bh, create); 446 if (!err) { 447 bh = affs_bread(inode->i_sb, tmp_bh.b_blocknr); 448 if (bh) { 449 bh->b_state |= tmp_bh.b_state; 450 return bh; 451 } 452 err = -EIO; 453 } 454 return ERR_PTR(err); 455 } 456 457 static inline struct buffer_head * 458 affs_getzeroblk_ino(struct inode *inode, int block) 459 { 460 struct buffer_head *bh, tmp_bh; 461 int err; 462 463 tmp_bh.b_state = 0; 464 err = affs_get_block(inode, block, &tmp_bh, 1); 465 if (!err) { 466 bh = affs_getzeroblk(inode->i_sb, tmp_bh.b_blocknr); 467 if (bh) { 468 bh->b_state |= tmp_bh.b_state; 469 return bh; 470 } 471 err = -EIO; 472 } 473 return ERR_PTR(err); 474 } 475 476 static inline struct buffer_head * 477 affs_getemptyblk_ino(struct inode *inode, int block) 478 { 479 struct buffer_head *bh, tmp_bh; 480 int err; 481 482 tmp_bh.b_state = 0; 483 err = affs_get_block(inode, block, &tmp_bh, 1); 484 if (!err) { 485 bh = affs_getemptyblk(inode->i_sb, tmp_bh.b_blocknr); 486 if (bh) { 487 bh->b_state |= tmp_bh.b_state; 488 return bh; 489 } 490 err = -EIO; 491 } 492 return ERR_PTR(err); 493 } 494 495 static int 496 affs_do_readpage_ofs(struct page *page, unsigned to) 497 { 498 struct inode *inode = page->mapping->host; 499 struct super_block *sb = inode->i_sb; 500 struct buffer_head *bh; 501 char *data; 502 unsigned pos = 0; 503 u32 bidx, boff, bsize; 504 u32 tmp; 505 506 pr_debug("%s(%u, %ld, 0, %d)\n", __func__, (u32)inode->i_ino, 507 page->index, to); 508 BUG_ON(to > PAGE_CACHE_SIZE); 509 kmap(page); 510 data = page_address(page); 511 bsize = AFFS_SB(sb)->s_data_blksize; 512 tmp = page->index << PAGE_CACHE_SHIFT; 513 bidx = tmp / bsize; 514 boff = tmp % bsize; 515 516 while (pos < to) { 517 bh = affs_bread_ino(inode, bidx, 0); 518 if (IS_ERR(bh)) 519 return PTR_ERR(bh); 520 tmp = min(bsize - boff, to - pos); 521 BUG_ON(pos + tmp > to || tmp > bsize); 522 memcpy(data + pos, AFFS_DATA(bh) + boff, tmp); 523 affs_brelse(bh); 524 bidx++; 525 pos += tmp; 526 boff = 0; 527 } 528 flush_dcache_page(page); 529 kunmap(page); 530 return 0; 531 } 532 533 static int 534 affs_extent_file_ofs(struct inode *inode, u32 newsize) 535 { 536 struct super_block *sb = inode->i_sb; 537 struct buffer_head *bh, *prev_bh; 538 u32 bidx, boff; 539 u32 size, bsize; 540 u32 tmp; 541 542 pr_debug("%s(%u, %d)\n", __func__, (u32)inode->i_ino, newsize); 543 bsize = AFFS_SB(sb)->s_data_blksize; 544 bh = NULL; 545 size = AFFS_I(inode)->mmu_private; 546 bidx = size / bsize; 547 boff = size % bsize; 548 if (boff) { 549 bh = affs_bread_ino(inode, bidx, 0); 550 if (IS_ERR(bh)) 551 return PTR_ERR(bh); 552 tmp = min(bsize - boff, newsize - size); 553 BUG_ON(boff + tmp > bsize || tmp > bsize); 554 memset(AFFS_DATA(bh) + boff, 0, tmp); 555 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp); 556 affs_fix_checksum(sb, bh); 557 mark_buffer_dirty_inode(bh, inode); 558 size += tmp; 559 bidx++; 560 } else if (bidx) { 561 bh = affs_bread_ino(inode, bidx - 1, 0); 562 if (IS_ERR(bh)) 563 return PTR_ERR(bh); 564 } 565 566 while (size < newsize) { 567 prev_bh = bh; 568 bh = affs_getzeroblk_ino(inode, bidx); 569 if (IS_ERR(bh)) 570 goto out; 571 tmp = min(bsize, newsize - size); 572 BUG_ON(tmp > bsize); 573 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); 574 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); 575 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); 576 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); 577 affs_fix_checksum(sb, bh); 578 bh->b_state &= ~(1UL << BH_New); 579 mark_buffer_dirty_inode(bh, inode); 580 if (prev_bh) { 581 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); 582 583 if (tmp_next) 584 affs_warning(sb, "extent_file_ofs", 585 "next block already set for %d (%d)", 586 bidx, tmp_next); 587 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); 588 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next); 589 mark_buffer_dirty_inode(prev_bh, inode); 590 affs_brelse(prev_bh); 591 } 592 size += bsize; 593 bidx++; 594 } 595 affs_brelse(bh); 596 inode->i_size = AFFS_I(inode)->mmu_private = newsize; 597 return 0; 598 599 out: 600 inode->i_size = AFFS_I(inode)->mmu_private = newsize; 601 return PTR_ERR(bh); 602 } 603 604 static int 605 affs_readpage_ofs(struct file *file, struct page *page) 606 { 607 struct inode *inode = page->mapping->host; 608 u32 to; 609 int err; 610 611 pr_debug("%s(%u, %ld)\n", __func__, (u32)inode->i_ino, page->index); 612 to = PAGE_CACHE_SIZE; 613 if (((page->index + 1) << PAGE_CACHE_SHIFT) > inode->i_size) { 614 to = inode->i_size & ~PAGE_CACHE_MASK; 615 memset(page_address(page) + to, 0, PAGE_CACHE_SIZE - to); 616 } 617 618 err = affs_do_readpage_ofs(page, to); 619 if (!err) 620 SetPageUptodate(page); 621 unlock_page(page); 622 return err; 623 } 624 625 static int affs_write_begin_ofs(struct file *file, struct address_space *mapping, 626 loff_t pos, unsigned len, unsigned flags, 627 struct page **pagep, void **fsdata) 628 { 629 struct inode *inode = mapping->host; 630 struct page *page; 631 pgoff_t index; 632 int err = 0; 633 634 pr_debug("%s(%u, %llu, %llu)\n", __func__, (u32)inode->i_ino, 635 (unsigned long long)pos, (unsigned long long)pos + len); 636 if (pos > AFFS_I(inode)->mmu_private) { 637 /* XXX: this probably leaves a too-big i_size in case of 638 * failure. Should really be updating i_size at write_end time 639 */ 640 err = affs_extent_file_ofs(inode, pos); 641 if (err) 642 return err; 643 } 644 645 index = pos >> PAGE_CACHE_SHIFT; 646 page = grab_cache_page_write_begin(mapping, index, flags); 647 if (!page) 648 return -ENOMEM; 649 *pagep = page; 650 651 if (PageUptodate(page)) 652 return 0; 653 654 /* XXX: inefficient but safe in the face of short writes */ 655 err = affs_do_readpage_ofs(page, PAGE_CACHE_SIZE); 656 if (err) { 657 unlock_page(page); 658 page_cache_release(page); 659 } 660 return err; 661 } 662 663 static int affs_write_end_ofs(struct file *file, struct address_space *mapping, 664 loff_t pos, unsigned len, unsigned copied, 665 struct page *page, void *fsdata) 666 { 667 struct inode *inode = mapping->host; 668 struct super_block *sb = inode->i_sb; 669 struct buffer_head *bh, *prev_bh; 670 char *data; 671 u32 bidx, boff, bsize; 672 unsigned from, to; 673 u32 tmp; 674 int written; 675 676 from = pos & (PAGE_CACHE_SIZE - 1); 677 to = pos + len; 678 /* 679 * XXX: not sure if this can handle short copies (len < copied), but 680 * we don't have to, because the page should always be uptodate here, 681 * due to write_begin. 682 */ 683 684 pr_debug("%s(%u, %llu, %llu)\n", 685 __func__, (u32)inode->i_ino, (unsigned long long)pos, 686 (unsigned long long)pos + len); 687 bsize = AFFS_SB(sb)->s_data_blksize; 688 data = page_address(page); 689 690 bh = NULL; 691 written = 0; 692 tmp = (page->index << PAGE_CACHE_SHIFT) + from; 693 bidx = tmp / bsize; 694 boff = tmp % bsize; 695 if (boff) { 696 bh = affs_bread_ino(inode, bidx, 0); 697 if (IS_ERR(bh)) 698 return PTR_ERR(bh); 699 tmp = min(bsize - boff, to - from); 700 BUG_ON(boff + tmp > bsize || tmp > bsize); 701 memcpy(AFFS_DATA(bh) + boff, data + from, tmp); 702 be32_add_cpu(&AFFS_DATA_HEAD(bh)->size, tmp); 703 affs_fix_checksum(sb, bh); 704 mark_buffer_dirty_inode(bh, inode); 705 written += tmp; 706 from += tmp; 707 bidx++; 708 } else if (bidx) { 709 bh = affs_bread_ino(inode, bidx - 1, 0); 710 if (IS_ERR(bh)) 711 return PTR_ERR(bh); 712 } 713 while (from + bsize <= to) { 714 prev_bh = bh; 715 bh = affs_getemptyblk_ino(inode, bidx); 716 if (IS_ERR(bh)) 717 goto out; 718 memcpy(AFFS_DATA(bh), data + from, bsize); 719 if (buffer_new(bh)) { 720 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); 721 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); 722 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); 723 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(bsize); 724 AFFS_DATA_HEAD(bh)->next = 0; 725 bh->b_state &= ~(1UL << BH_New); 726 if (prev_bh) { 727 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); 728 729 if (tmp_next) 730 affs_warning(sb, "commit_write_ofs", 731 "next block already set for %d (%d)", 732 bidx, tmp_next); 733 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); 734 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next); 735 mark_buffer_dirty_inode(prev_bh, inode); 736 } 737 } 738 affs_brelse(prev_bh); 739 affs_fix_checksum(sb, bh); 740 mark_buffer_dirty_inode(bh, inode); 741 written += bsize; 742 from += bsize; 743 bidx++; 744 } 745 if (from < to) { 746 prev_bh = bh; 747 bh = affs_bread_ino(inode, bidx, 1); 748 if (IS_ERR(bh)) 749 goto out; 750 tmp = min(bsize, to - from); 751 BUG_ON(tmp > bsize); 752 memcpy(AFFS_DATA(bh), data + from, tmp); 753 if (buffer_new(bh)) { 754 AFFS_DATA_HEAD(bh)->ptype = cpu_to_be32(T_DATA); 755 AFFS_DATA_HEAD(bh)->key = cpu_to_be32(inode->i_ino); 756 AFFS_DATA_HEAD(bh)->sequence = cpu_to_be32(bidx); 757 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); 758 AFFS_DATA_HEAD(bh)->next = 0; 759 bh->b_state &= ~(1UL << BH_New); 760 if (prev_bh) { 761 u32 tmp_next = be32_to_cpu(AFFS_DATA_HEAD(prev_bh)->next); 762 763 if (tmp_next) 764 affs_warning(sb, "commit_write_ofs", 765 "next block already set for %d (%d)", 766 bidx, tmp_next); 767 AFFS_DATA_HEAD(prev_bh)->next = cpu_to_be32(bh->b_blocknr); 768 affs_adjust_checksum(prev_bh, bh->b_blocknr - tmp_next); 769 mark_buffer_dirty_inode(prev_bh, inode); 770 } 771 } else if (be32_to_cpu(AFFS_DATA_HEAD(bh)->size) < tmp) 772 AFFS_DATA_HEAD(bh)->size = cpu_to_be32(tmp); 773 affs_brelse(prev_bh); 774 affs_fix_checksum(sb, bh); 775 mark_buffer_dirty_inode(bh, inode); 776 written += tmp; 777 from += tmp; 778 bidx++; 779 } 780 SetPageUptodate(page); 781 782 done: 783 affs_brelse(bh); 784 tmp = (page->index << PAGE_CACHE_SHIFT) + from; 785 if (tmp > inode->i_size) 786 inode->i_size = AFFS_I(inode)->mmu_private = tmp; 787 788 unlock_page(page); 789 page_cache_release(page); 790 791 return written; 792 793 out: 794 bh = prev_bh; 795 if (!written) 796 written = PTR_ERR(bh); 797 goto done; 798 } 799 800 const struct address_space_operations affs_aops_ofs = { 801 .readpage = affs_readpage_ofs, 802 //.writepage = affs_writepage_ofs, 803 .write_begin = affs_write_begin_ofs, 804 .write_end = affs_write_end_ofs 805 }; 806 807 /* Free any preallocated blocks. */ 808 809 void 810 affs_free_prealloc(struct inode *inode) 811 { 812 struct super_block *sb = inode->i_sb; 813 814 pr_debug("free_prealloc(ino=%lu)\n", inode->i_ino); 815 816 while (AFFS_I(inode)->i_pa_cnt) { 817 AFFS_I(inode)->i_pa_cnt--; 818 affs_free_block(sb, ++AFFS_I(inode)->i_lastalloc); 819 } 820 } 821 822 /* Truncate (or enlarge) a file to the requested size. */ 823 824 void 825 affs_truncate(struct inode *inode) 826 { 827 struct super_block *sb = inode->i_sb; 828 u32 ext, ext_key; 829 u32 last_blk, blkcnt, blk; 830 u32 size; 831 struct buffer_head *ext_bh; 832 int i; 833 834 pr_debug("truncate(inode=%d, oldsize=%u, newsize=%u)\n", 835 (u32)inode->i_ino, (u32)AFFS_I(inode)->mmu_private, (u32)inode->i_size); 836 837 last_blk = 0; 838 ext = 0; 839 if (inode->i_size) { 840 last_blk = ((u32)inode->i_size - 1) / AFFS_SB(sb)->s_data_blksize; 841 ext = last_blk / AFFS_SB(sb)->s_hashsize; 842 } 843 844 if (inode->i_size > AFFS_I(inode)->mmu_private) { 845 struct address_space *mapping = inode->i_mapping; 846 struct page *page; 847 void *fsdata; 848 loff_t isize = inode->i_size; 849 int res; 850 851 res = mapping->a_ops->write_begin(NULL, mapping, isize, 0, 0, &page, &fsdata); 852 if (!res) 853 res = mapping->a_ops->write_end(NULL, mapping, isize, 0, 0, page, fsdata); 854 else 855 inode->i_size = AFFS_I(inode)->mmu_private; 856 mark_inode_dirty(inode); 857 return; 858 } else if (inode->i_size == AFFS_I(inode)->mmu_private) 859 return; 860 861 // lock cache 862 ext_bh = affs_get_extblock(inode, ext); 863 if (IS_ERR(ext_bh)) { 864 affs_warning(sb, "truncate", 865 "unexpected read error for ext block %u (%ld)", 866 (unsigned int)ext, PTR_ERR(ext_bh)); 867 return; 868 } 869 if (AFFS_I(inode)->i_lc) { 870 /* clear linear cache */ 871 i = (ext + 1) >> AFFS_I(inode)->i_lc_shift; 872 if (AFFS_I(inode)->i_lc_size > i) { 873 AFFS_I(inode)->i_lc_size = i; 874 for (; i < AFFS_LC_SIZE; i++) 875 AFFS_I(inode)->i_lc[i] = 0; 876 } 877 /* clear associative cache */ 878 for (i = 0; i < AFFS_AC_SIZE; i++) 879 if (AFFS_I(inode)->i_ac[i].ext >= ext) 880 AFFS_I(inode)->i_ac[i].ext = 0; 881 } 882 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension); 883 884 blkcnt = AFFS_I(inode)->i_blkcnt; 885 i = 0; 886 blk = last_blk; 887 if (inode->i_size) { 888 i = last_blk % AFFS_SB(sb)->s_hashsize + 1; 889 blk++; 890 } else 891 AFFS_HEAD(ext_bh)->first_data = 0; 892 AFFS_HEAD(ext_bh)->block_count = cpu_to_be32(i); 893 size = AFFS_SB(sb)->s_hashsize; 894 if (size > blkcnt - blk + i) 895 size = blkcnt - blk + i; 896 for (; i < size; i++, blk++) { 897 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i))); 898 AFFS_BLOCK(sb, ext_bh, i) = 0; 899 } 900 AFFS_TAIL(sb, ext_bh)->extension = 0; 901 affs_fix_checksum(sb, ext_bh); 902 mark_buffer_dirty_inode(ext_bh, inode); 903 affs_brelse(ext_bh); 904 905 if (inode->i_size) { 906 AFFS_I(inode)->i_blkcnt = last_blk + 1; 907 AFFS_I(inode)->i_extcnt = ext + 1; 908 if (AFFS_SB(sb)->s_flags & SF_OFS) { 909 struct buffer_head *bh = affs_bread_ino(inode, last_blk, 0); 910 u32 tmp; 911 if (IS_ERR(bh)) { 912 affs_warning(sb, "truncate", 913 "unexpected read error for last block %u (%ld)", 914 (unsigned int)ext, PTR_ERR(bh)); 915 return; 916 } 917 tmp = be32_to_cpu(AFFS_DATA_HEAD(bh)->next); 918 AFFS_DATA_HEAD(bh)->next = 0; 919 affs_adjust_checksum(bh, -tmp); 920 affs_brelse(bh); 921 } 922 } else { 923 AFFS_I(inode)->i_blkcnt = 0; 924 AFFS_I(inode)->i_extcnt = 1; 925 } 926 AFFS_I(inode)->mmu_private = inode->i_size; 927 // unlock cache 928 929 while (ext_key) { 930 ext_bh = affs_bread(sb, ext_key); 931 size = AFFS_SB(sb)->s_hashsize; 932 if (size > blkcnt - blk) 933 size = blkcnt - blk; 934 for (i = 0; i < size; i++, blk++) 935 affs_free_block(sb, be32_to_cpu(AFFS_BLOCK(sb, ext_bh, i))); 936 affs_free_block(sb, ext_key); 937 ext_key = be32_to_cpu(AFFS_TAIL(sb, ext_bh)->extension); 938 affs_brelse(ext_bh); 939 } 940 affs_free_prealloc(inode); 941 } 942 943 int affs_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync) 944 { 945 struct inode *inode = filp->f_mapping->host; 946 int ret, err; 947 948 err = filemap_write_and_wait_range(inode->i_mapping, start, end); 949 if (err) 950 return err; 951 952 mutex_lock(&inode->i_mutex); 953 ret = write_inode_now(inode, 0); 954 err = sync_blockdev(inode->i_sb->s_bdev); 955 if (!ret) 956 ret = err; 957 mutex_unlock(&inode->i_mutex); 958 return ret; 959 } 960 const struct file_operations affs_file_operations = { 961 .llseek = generic_file_llseek, 962 .read = new_sync_read, 963 .read_iter = generic_file_read_iter, 964 .write = new_sync_write, 965 .write_iter = generic_file_write_iter, 966 .mmap = generic_file_mmap, 967 .open = affs_file_open, 968 .release = affs_file_release, 969 .fsync = affs_file_fsync, 970 .splice_read = generic_file_splice_read, 971 }; 972 973 const struct inode_operations affs_file_inode_operations = { 974 .setattr = affs_notify_change, 975 }; 976