1 /* 2 * linux/fs/ext2/inode.c 3 * 4 * Copyright (C) 1992, 1993, 1994, 1995 5 * Remy Card (card@masi.ibp.fr) 6 * Laboratoire MASI - Institut Blaise Pascal 7 * Universite Pierre et Marie Curie (Paris VI) 8 * 9 * from 10 * 11 * linux/fs/minix/inode.c 12 * 13 * Copyright (C) 1991, 1992 Linus Torvalds 14 * 15 * Goal-directed block allocation by Stephen Tweedie 16 * (sct@dcs.ed.ac.uk), 1993, 1998 17 * Big-endian to little-endian byte-swapping/bitmaps by 18 * David S. Miller (davem@caip.rutgers.edu), 1995 19 * 64-bit file support on 64-bit platforms by Jakub Jelinek 20 * (jj@sunsite.ms.mff.cuni.cz) 21 * 22 * Assorted race fixes, rewrite of ext2_get_block() by Al Viro, 2000 23 */ 24 25 #include <linux/smp_lock.h> 26 #include <linux/time.h> 27 #include <linux/highuid.h> 28 #include <linux/pagemap.h> 29 #include <linux/quotaops.h> 30 #include <linux/module.h> 31 #include <linux/writeback.h> 32 #include <linux/buffer_head.h> 33 #include <linux/mpage.h> 34 #include "ext2.h" 35 #include "acl.h" 36 #include "xip.h" 37 38 MODULE_AUTHOR("Remy Card and others"); 39 MODULE_DESCRIPTION("Second Extended Filesystem"); 40 MODULE_LICENSE("GPL"); 41 42 static int ext2_update_inode(struct inode * inode, int do_sync); 43 44 /* 45 * Test whether an inode is a fast symlink. 46 */ 47 static inline int ext2_inode_is_fast_symlink(struct inode *inode) 48 { 49 int ea_blocks = EXT2_I(inode)->i_file_acl ? 50 (inode->i_sb->s_blocksize >> 9) : 0; 51 52 return (S_ISLNK(inode->i_mode) && 53 inode->i_blocks - ea_blocks == 0); 54 } 55 56 /* 57 * Called at each iput(). 58 * 59 * The inode may be "bad" if ext2_read_inode() saw an error from 60 * ext2_get_inode(), so we need to check that to avoid freeing random disk 61 * blocks. 62 */ 63 void ext2_put_inode(struct inode *inode) 64 { 65 if (!is_bad_inode(inode)) 66 ext2_discard_prealloc(inode); 67 } 68 69 /* 70 * Called at the last iput() if i_nlink is zero. 71 */ 72 void ext2_delete_inode (struct inode * inode) 73 { 74 truncate_inode_pages(&inode->i_data, 0); 75 76 if (is_bad_inode(inode)) 77 goto no_delete; 78 EXT2_I(inode)->i_dtime = get_seconds(); 79 mark_inode_dirty(inode); 80 ext2_update_inode(inode, inode_needs_sync(inode)); 81 82 inode->i_size = 0; 83 if (inode->i_blocks) 84 ext2_truncate (inode); 85 ext2_free_inode (inode); 86 87 return; 88 no_delete: 89 clear_inode(inode); /* We must guarantee clearing of inode... */ 90 } 91 92 void ext2_discard_prealloc (struct inode * inode) 93 { 94 #ifdef EXT2_PREALLOCATE 95 struct ext2_inode_info *ei = EXT2_I(inode); 96 write_lock(&ei->i_meta_lock); 97 if (ei->i_prealloc_count) { 98 unsigned short total = ei->i_prealloc_count; 99 unsigned long block = ei->i_prealloc_block; 100 ei->i_prealloc_count = 0; 101 ei->i_prealloc_block = 0; 102 write_unlock(&ei->i_meta_lock); 103 ext2_free_blocks (inode, block, total); 104 return; 105 } else 106 write_unlock(&ei->i_meta_lock); 107 #endif 108 } 109 110 static int ext2_alloc_block (struct inode * inode, unsigned long goal, int *err) 111 { 112 #ifdef EXT2FS_DEBUG 113 static unsigned long alloc_hits, alloc_attempts; 114 #endif 115 unsigned long result; 116 117 118 #ifdef EXT2_PREALLOCATE 119 struct ext2_inode_info *ei = EXT2_I(inode); 120 write_lock(&ei->i_meta_lock); 121 if (ei->i_prealloc_count && 122 (goal == ei->i_prealloc_block || goal + 1 == ei->i_prealloc_block)) 123 { 124 result = ei->i_prealloc_block++; 125 ei->i_prealloc_count--; 126 write_unlock(&ei->i_meta_lock); 127 ext2_debug ("preallocation hit (%lu/%lu).\n", 128 ++alloc_hits, ++alloc_attempts); 129 } else { 130 write_unlock(&ei->i_meta_lock); 131 ext2_discard_prealloc (inode); 132 ext2_debug ("preallocation miss (%lu/%lu).\n", 133 alloc_hits, ++alloc_attempts); 134 if (S_ISREG(inode->i_mode)) 135 result = ext2_new_block (inode, goal, 136 &ei->i_prealloc_count, 137 &ei->i_prealloc_block, err); 138 else 139 result = ext2_new_block(inode, goal, NULL, NULL, err); 140 } 141 #else 142 result = ext2_new_block (inode, goal, 0, 0, err); 143 #endif 144 return result; 145 } 146 147 typedef struct { 148 __le32 *p; 149 __le32 key; 150 struct buffer_head *bh; 151 } Indirect; 152 153 static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v) 154 { 155 p->key = *(p->p = v); 156 p->bh = bh; 157 } 158 159 static inline int verify_chain(Indirect *from, Indirect *to) 160 { 161 while (from <= to && from->key == *from->p) 162 from++; 163 return (from > to); 164 } 165 166 /** 167 * ext2_block_to_path - parse the block number into array of offsets 168 * @inode: inode in question (we are only interested in its superblock) 169 * @i_block: block number to be parsed 170 * @offsets: array to store the offsets in 171 * @boundary: set this non-zero if the referred-to block is likely to be 172 * followed (on disk) by an indirect block. 173 * To store the locations of file's data ext2 uses a data structure common 174 * for UNIX filesystems - tree of pointers anchored in the inode, with 175 * data blocks at leaves and indirect blocks in intermediate nodes. 176 * This function translates the block number into path in that tree - 177 * return value is the path length and @offsets[n] is the offset of 178 * pointer to (n+1)th node in the nth one. If @block is out of range 179 * (negative or too large) warning is printed and zero returned. 180 * 181 * Note: function doesn't find node addresses, so no IO is needed. All 182 * we need to know is the capacity of indirect blocks (taken from the 183 * inode->i_sb). 184 */ 185 186 /* 187 * Portability note: the last comparison (check that we fit into triple 188 * indirect block) is spelled differently, because otherwise on an 189 * architecture with 32-bit longs and 8Kb pages we might get into trouble 190 * if our filesystem had 8Kb blocks. We might use long long, but that would 191 * kill us on x86. Oh, well, at least the sign propagation does not matter - 192 * i_block would have to be negative in the very beginning, so we would not 193 * get there at all. 194 */ 195 196 static int ext2_block_to_path(struct inode *inode, 197 long i_block, int offsets[4], int *boundary) 198 { 199 int ptrs = EXT2_ADDR_PER_BLOCK(inode->i_sb); 200 int ptrs_bits = EXT2_ADDR_PER_BLOCK_BITS(inode->i_sb); 201 const long direct_blocks = EXT2_NDIR_BLOCKS, 202 indirect_blocks = ptrs, 203 double_blocks = (1 << (ptrs_bits * 2)); 204 int n = 0; 205 int final = 0; 206 207 if (i_block < 0) { 208 ext2_warning (inode->i_sb, "ext2_block_to_path", "block < 0"); 209 } else if (i_block < direct_blocks) { 210 offsets[n++] = i_block; 211 final = direct_blocks; 212 } else if ( (i_block -= direct_blocks) < indirect_blocks) { 213 offsets[n++] = EXT2_IND_BLOCK; 214 offsets[n++] = i_block; 215 final = ptrs; 216 } else if ((i_block -= indirect_blocks) < double_blocks) { 217 offsets[n++] = EXT2_DIND_BLOCK; 218 offsets[n++] = i_block >> ptrs_bits; 219 offsets[n++] = i_block & (ptrs - 1); 220 final = ptrs; 221 } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) { 222 offsets[n++] = EXT2_TIND_BLOCK; 223 offsets[n++] = i_block >> (ptrs_bits * 2); 224 offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1); 225 offsets[n++] = i_block & (ptrs - 1); 226 final = ptrs; 227 } else { 228 ext2_warning (inode->i_sb, "ext2_block_to_path", "block > big"); 229 } 230 if (boundary) 231 *boundary = (i_block & (ptrs - 1)) == (final - 1); 232 return n; 233 } 234 235 /** 236 * ext2_get_branch - read the chain of indirect blocks leading to data 237 * @inode: inode in question 238 * @depth: depth of the chain (1 - direct pointer, etc.) 239 * @offsets: offsets of pointers in inode/indirect blocks 240 * @chain: place to store the result 241 * @err: here we store the error value 242 * 243 * Function fills the array of triples <key, p, bh> and returns %NULL 244 * if everything went OK or the pointer to the last filled triple 245 * (incomplete one) otherwise. Upon the return chain[i].key contains 246 * the number of (i+1)-th block in the chain (as it is stored in memory, 247 * i.e. little-endian 32-bit), chain[i].p contains the address of that 248 * number (it points into struct inode for i==0 and into the bh->b_data 249 * for i>0) and chain[i].bh points to the buffer_head of i-th indirect 250 * block for i>0 and NULL for i==0. In other words, it holds the block 251 * numbers of the chain, addresses they were taken from (and where we can 252 * verify that chain did not change) and buffer_heads hosting these 253 * numbers. 254 * 255 * Function stops when it stumbles upon zero pointer (absent block) 256 * (pointer to last triple returned, *@err == 0) 257 * or when it gets an IO error reading an indirect block 258 * (ditto, *@err == -EIO) 259 * or when it notices that chain had been changed while it was reading 260 * (ditto, *@err == -EAGAIN) 261 * or when it reads all @depth-1 indirect blocks successfully and finds 262 * the whole chain, all way to the data (returns %NULL, *err == 0). 263 */ 264 static Indirect *ext2_get_branch(struct inode *inode, 265 int depth, 266 int *offsets, 267 Indirect chain[4], 268 int *err) 269 { 270 struct super_block *sb = inode->i_sb; 271 Indirect *p = chain; 272 struct buffer_head *bh; 273 274 *err = 0; 275 /* i_data is not going away, no lock needed */ 276 add_chain (chain, NULL, EXT2_I(inode)->i_data + *offsets); 277 if (!p->key) 278 goto no_block; 279 while (--depth) { 280 bh = sb_bread(sb, le32_to_cpu(p->key)); 281 if (!bh) 282 goto failure; 283 read_lock(&EXT2_I(inode)->i_meta_lock); 284 if (!verify_chain(chain, p)) 285 goto changed; 286 add_chain(++p, bh, (__le32*)bh->b_data + *++offsets); 287 read_unlock(&EXT2_I(inode)->i_meta_lock); 288 if (!p->key) 289 goto no_block; 290 } 291 return NULL; 292 293 changed: 294 read_unlock(&EXT2_I(inode)->i_meta_lock); 295 brelse(bh); 296 *err = -EAGAIN; 297 goto no_block; 298 failure: 299 *err = -EIO; 300 no_block: 301 return p; 302 } 303 304 /** 305 * ext2_find_near - find a place for allocation with sufficient locality 306 * @inode: owner 307 * @ind: descriptor of indirect block. 308 * 309 * This function returns the prefered place for block allocation. 310 * It is used when heuristic for sequential allocation fails. 311 * Rules are: 312 * + if there is a block to the left of our position - allocate near it. 313 * + if pointer will live in indirect block - allocate near that block. 314 * + if pointer will live in inode - allocate in the same cylinder group. 315 * 316 * In the latter case we colour the starting block by the callers PID to 317 * prevent it from clashing with concurrent allocations for a different inode 318 * in the same block group. The PID is used here so that functionally related 319 * files will be close-by on-disk. 320 * 321 * Caller must make sure that @ind is valid and will stay that way. 322 */ 323 324 static unsigned long ext2_find_near(struct inode *inode, Indirect *ind) 325 { 326 struct ext2_inode_info *ei = EXT2_I(inode); 327 __le32 *start = ind->bh ? (__le32 *) ind->bh->b_data : ei->i_data; 328 __le32 *p; 329 unsigned long bg_start; 330 unsigned long colour; 331 332 /* Try to find previous block */ 333 for (p = ind->p - 1; p >= start; p--) 334 if (*p) 335 return le32_to_cpu(*p); 336 337 /* No such thing, so let's try location of indirect block */ 338 if (ind->bh) 339 return ind->bh->b_blocknr; 340 341 /* 342 * It is going to be refered from inode itself? OK, just put it into 343 * the same cylinder group then. 344 */ 345 bg_start = (ei->i_block_group * EXT2_BLOCKS_PER_GROUP(inode->i_sb)) + 346 le32_to_cpu(EXT2_SB(inode->i_sb)->s_es->s_first_data_block); 347 colour = (current->pid % 16) * 348 (EXT2_BLOCKS_PER_GROUP(inode->i_sb) / 16); 349 return bg_start + colour; 350 } 351 352 /** 353 * ext2_find_goal - find a prefered place for allocation. 354 * @inode: owner 355 * @block: block we want 356 * @chain: chain of indirect blocks 357 * @partial: pointer to the last triple within a chain 358 * @goal: place to store the result. 359 * 360 * Normally this function find the prefered place for block allocation, 361 * stores it in *@goal and returns zero. If the branch had been changed 362 * under us we return -EAGAIN. 363 */ 364 365 static inline int ext2_find_goal(struct inode *inode, 366 long block, 367 Indirect chain[4], 368 Indirect *partial, 369 unsigned long *goal) 370 { 371 struct ext2_inode_info *ei = EXT2_I(inode); 372 write_lock(&ei->i_meta_lock); 373 if ((block == ei->i_next_alloc_block + 1) && ei->i_next_alloc_goal) { 374 ei->i_next_alloc_block++; 375 ei->i_next_alloc_goal++; 376 } 377 if (verify_chain(chain, partial)) { 378 /* 379 * try the heuristic for sequential allocation, 380 * failing that at least try to get decent locality. 381 */ 382 if (block == ei->i_next_alloc_block) 383 *goal = ei->i_next_alloc_goal; 384 if (!*goal) 385 *goal = ext2_find_near(inode, partial); 386 write_unlock(&ei->i_meta_lock); 387 return 0; 388 } 389 write_unlock(&ei->i_meta_lock); 390 return -EAGAIN; 391 } 392 393 /** 394 * ext2_alloc_branch - allocate and set up a chain of blocks. 395 * @inode: owner 396 * @num: depth of the chain (number of blocks to allocate) 397 * @offsets: offsets (in the blocks) to store the pointers to next. 398 * @branch: place to store the chain in. 399 * 400 * This function allocates @num blocks, zeroes out all but the last one, 401 * links them into chain and (if we are synchronous) writes them to disk. 402 * In other words, it prepares a branch that can be spliced onto the 403 * inode. It stores the information about that chain in the branch[], in 404 * the same format as ext2_get_branch() would do. We are calling it after 405 * we had read the existing part of chain and partial points to the last 406 * triple of that (one with zero ->key). Upon the exit we have the same 407 * picture as after the successful ext2_get_block(), excpet that in one 408 * place chain is disconnected - *branch->p is still zero (we did not 409 * set the last link), but branch->key contains the number that should 410 * be placed into *branch->p to fill that gap. 411 * 412 * If allocation fails we free all blocks we've allocated (and forget 413 * their buffer_heads) and return the error value the from failed 414 * ext2_alloc_block() (normally -ENOSPC). Otherwise we set the chain 415 * as described above and return 0. 416 */ 417 418 static int ext2_alloc_branch(struct inode *inode, 419 int num, 420 unsigned long goal, 421 int *offsets, 422 Indirect *branch) 423 { 424 int blocksize = inode->i_sb->s_blocksize; 425 int n = 0; 426 int err; 427 int i; 428 int parent = ext2_alloc_block(inode, goal, &err); 429 430 branch[0].key = cpu_to_le32(parent); 431 if (parent) for (n = 1; n < num; n++) { 432 struct buffer_head *bh; 433 /* Allocate the next block */ 434 int nr = ext2_alloc_block(inode, parent, &err); 435 if (!nr) 436 break; 437 branch[n].key = cpu_to_le32(nr); 438 /* 439 * Get buffer_head for parent block, zero it out and set 440 * the pointer to new one, then send parent to disk. 441 */ 442 bh = sb_getblk(inode->i_sb, parent); 443 if (!bh) { 444 err = -EIO; 445 break; 446 } 447 lock_buffer(bh); 448 memset(bh->b_data, 0, blocksize); 449 branch[n].bh = bh; 450 branch[n].p = (__le32 *) bh->b_data + offsets[n]; 451 *branch[n].p = branch[n].key; 452 set_buffer_uptodate(bh); 453 unlock_buffer(bh); 454 mark_buffer_dirty_inode(bh, inode); 455 /* We used to sync bh here if IS_SYNC(inode). 456 * But we now rely upon generic_osync_inode() 457 * and b_inode_buffers. But not for directories. 458 */ 459 if (S_ISDIR(inode->i_mode) && IS_DIRSYNC(inode)) 460 sync_dirty_buffer(bh); 461 parent = nr; 462 } 463 if (n == num) 464 return 0; 465 466 /* Allocation failed, free what we already allocated */ 467 for (i = 1; i < n; i++) 468 bforget(branch[i].bh); 469 for (i = 0; i < n; i++) 470 ext2_free_blocks(inode, le32_to_cpu(branch[i].key), 1); 471 return err; 472 } 473 474 /** 475 * ext2_splice_branch - splice the allocated branch onto inode. 476 * @inode: owner 477 * @block: (logical) number of block we are adding 478 * @chain: chain of indirect blocks (with a missing link - see 479 * ext2_alloc_branch) 480 * @where: location of missing link 481 * @num: number of blocks we are adding 482 * 483 * This function verifies that chain (up to the missing link) had not 484 * changed, fills the missing link and does all housekeeping needed in 485 * inode (->i_blocks, etc.). In case of success we end up with the full 486 * chain to new block and return 0. Otherwise (== chain had been changed) 487 * we free the new blocks (forgetting their buffer_heads, indeed) and 488 * return -EAGAIN. 489 */ 490 491 static inline int ext2_splice_branch(struct inode *inode, 492 long block, 493 Indirect chain[4], 494 Indirect *where, 495 int num) 496 { 497 struct ext2_inode_info *ei = EXT2_I(inode); 498 int i; 499 500 /* Verify that place we are splicing to is still there and vacant */ 501 502 write_lock(&ei->i_meta_lock); 503 if (!verify_chain(chain, where-1) || *where->p) 504 goto changed; 505 506 /* That's it */ 507 508 *where->p = where->key; 509 ei->i_next_alloc_block = block; 510 ei->i_next_alloc_goal = le32_to_cpu(where[num-1].key); 511 512 write_unlock(&ei->i_meta_lock); 513 514 /* We are done with atomic stuff, now do the rest of housekeeping */ 515 516 inode->i_ctime = CURRENT_TIME_SEC; 517 518 /* had we spliced it onto indirect block? */ 519 if (where->bh) 520 mark_buffer_dirty_inode(where->bh, inode); 521 522 mark_inode_dirty(inode); 523 return 0; 524 525 changed: 526 write_unlock(&ei->i_meta_lock); 527 for (i = 1; i < num; i++) 528 bforget(where[i].bh); 529 for (i = 0; i < num; i++) 530 ext2_free_blocks(inode, le32_to_cpu(where[i].key), 1); 531 return -EAGAIN; 532 } 533 534 /* 535 * Allocation strategy is simple: if we have to allocate something, we will 536 * have to go the whole way to leaf. So let's do it before attaching anything 537 * to tree, set linkage between the newborn blocks, write them if sync is 538 * required, recheck the path, free and repeat if check fails, otherwise 539 * set the last missing link (that will protect us from any truncate-generated 540 * removals - all blocks on the path are immune now) and possibly force the 541 * write on the parent block. 542 * That has a nice additional property: no special recovery from the failed 543 * allocations is needed - we simply release blocks and do not touch anything 544 * reachable from inode. 545 */ 546 547 int ext2_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) 548 { 549 int err = -EIO; 550 int offsets[4]; 551 Indirect chain[4]; 552 Indirect *partial; 553 unsigned long goal; 554 int left; 555 int boundary = 0; 556 int depth = ext2_block_to_path(inode, iblock, offsets, &boundary); 557 558 if (depth == 0) 559 goto out; 560 561 reread: 562 partial = ext2_get_branch(inode, depth, offsets, chain, &err); 563 564 /* Simplest case - block found, no allocation needed */ 565 if (!partial) { 566 got_it: 567 map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key)); 568 if (boundary) 569 set_buffer_boundary(bh_result); 570 /* Clean up and exit */ 571 partial = chain+depth-1; /* the whole chain */ 572 goto cleanup; 573 } 574 575 /* Next simple case - plain lookup or failed read of indirect block */ 576 if (!create || err == -EIO) { 577 cleanup: 578 while (partial > chain) { 579 brelse(partial->bh); 580 partial--; 581 } 582 out: 583 return err; 584 } 585 586 /* 587 * Indirect block might be removed by truncate while we were 588 * reading it. Handling of that case (forget what we've got and 589 * reread) is taken out of the main path. 590 */ 591 if (err == -EAGAIN) 592 goto changed; 593 594 goal = 0; 595 if (ext2_find_goal(inode, iblock, chain, partial, &goal) < 0) 596 goto changed; 597 598 left = (chain + depth) - partial; 599 err = ext2_alloc_branch(inode, left, goal, 600 offsets+(partial-chain), partial); 601 if (err) 602 goto cleanup; 603 604 if (ext2_use_xip(inode->i_sb)) { 605 /* 606 * we need to clear the block 607 */ 608 err = ext2_clear_xip_target (inode, 609 le32_to_cpu(chain[depth-1].key)); 610 if (err) 611 goto cleanup; 612 } 613 614 if (ext2_splice_branch(inode, iblock, chain, partial, left) < 0) 615 goto changed; 616 617 set_buffer_new(bh_result); 618 goto got_it; 619 620 changed: 621 while (partial > chain) { 622 brelse(partial->bh); 623 partial--; 624 } 625 goto reread; 626 } 627 628 static int ext2_writepage(struct page *page, struct writeback_control *wbc) 629 { 630 return block_write_full_page(page, ext2_get_block, wbc); 631 } 632 633 static int ext2_readpage(struct file *file, struct page *page) 634 { 635 return mpage_readpage(page, ext2_get_block); 636 } 637 638 static int 639 ext2_readpages(struct file *file, struct address_space *mapping, 640 struct list_head *pages, unsigned nr_pages) 641 { 642 return mpage_readpages(mapping, pages, nr_pages, ext2_get_block); 643 } 644 645 int __ext2_write_begin(struct file *file, struct address_space *mapping, 646 loff_t pos, unsigned len, unsigned flags, 647 struct page **pagep, void **fsdata) 648 { 649 return block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, 650 ext2_get_block); 651 } 652 653 static int 654 ext2_write_begin(struct file *file, struct address_space *mapping, 655 loff_t pos, unsigned len, unsigned flags, 656 struct page **pagep, void **fsdata) 657 { 658 *pagep = NULL; 659 return __ext2_write_begin(file, mapping, pos, len, flags, pagep,fsdata); 660 } 661 662 static int 663 ext2_nobh_write_begin(struct file *file, struct address_space *mapping, 664 loff_t pos, unsigned len, unsigned flags, 665 struct page **pagep, void **fsdata) 666 { 667 /* 668 * Dir-in-pagecache still uses ext2_write_begin. Would have to rework 669 * directory handling code to pass around offsets rather than struct 670 * pages in order to make this work easily. 671 */ 672 return nobh_write_begin(file, mapping, pos, len, flags, pagep, fsdata, 673 ext2_get_block); 674 } 675 676 static int ext2_nobh_writepage(struct page *page, 677 struct writeback_control *wbc) 678 { 679 return nobh_writepage(page, ext2_get_block, wbc); 680 } 681 682 static sector_t ext2_bmap(struct address_space *mapping, sector_t block) 683 { 684 return generic_block_bmap(mapping,block,ext2_get_block); 685 } 686 687 static ssize_t 688 ext2_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov, 689 loff_t offset, unsigned long nr_segs) 690 { 691 struct file *file = iocb->ki_filp; 692 struct inode *inode = file->f_mapping->host; 693 694 return blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov, 695 offset, nr_segs, ext2_get_block, NULL); 696 } 697 698 static int 699 ext2_writepages(struct address_space *mapping, struct writeback_control *wbc) 700 { 701 return mpage_writepages(mapping, wbc, ext2_get_block); 702 } 703 704 const struct address_space_operations ext2_aops = { 705 .readpage = ext2_readpage, 706 .readpages = ext2_readpages, 707 .writepage = ext2_writepage, 708 .sync_page = block_sync_page, 709 .write_begin = ext2_write_begin, 710 .write_end = generic_write_end, 711 .bmap = ext2_bmap, 712 .direct_IO = ext2_direct_IO, 713 .writepages = ext2_writepages, 714 .migratepage = buffer_migrate_page, 715 }; 716 717 const struct address_space_operations ext2_aops_xip = { 718 .bmap = ext2_bmap, 719 .get_xip_page = ext2_get_xip_page, 720 }; 721 722 const struct address_space_operations ext2_nobh_aops = { 723 .readpage = ext2_readpage, 724 .readpages = ext2_readpages, 725 .writepage = ext2_nobh_writepage, 726 .sync_page = block_sync_page, 727 .write_begin = ext2_nobh_write_begin, 728 .write_end = nobh_write_end, 729 .bmap = ext2_bmap, 730 .direct_IO = ext2_direct_IO, 731 .writepages = ext2_writepages, 732 .migratepage = buffer_migrate_page, 733 }; 734 735 /* 736 * Probably it should be a library function... search for first non-zero word 737 * or memcmp with zero_page, whatever is better for particular architecture. 738 * Linus? 739 */ 740 static inline int all_zeroes(__le32 *p, __le32 *q) 741 { 742 while (p < q) 743 if (*p++) 744 return 0; 745 return 1; 746 } 747 748 /** 749 * ext2_find_shared - find the indirect blocks for partial truncation. 750 * @inode: inode in question 751 * @depth: depth of the affected branch 752 * @offsets: offsets of pointers in that branch (see ext2_block_to_path) 753 * @chain: place to store the pointers to partial indirect blocks 754 * @top: place to the (detached) top of branch 755 * 756 * This is a helper function used by ext2_truncate(). 757 * 758 * When we do truncate() we may have to clean the ends of several indirect 759 * blocks but leave the blocks themselves alive. Block is partially 760 * truncated if some data below the new i_size is refered from it (and 761 * it is on the path to the first completely truncated data block, indeed). 762 * We have to free the top of that path along with everything to the right 763 * of the path. Since no allocation past the truncation point is possible 764 * until ext2_truncate() finishes, we may safely do the latter, but top 765 * of branch may require special attention - pageout below the truncation 766 * point might try to populate it. 767 * 768 * We atomically detach the top of branch from the tree, store the block 769 * number of its root in *@top, pointers to buffer_heads of partially 770 * truncated blocks - in @chain[].bh and pointers to their last elements 771 * that should not be removed - in @chain[].p. Return value is the pointer 772 * to last filled element of @chain. 773 * 774 * The work left to caller to do the actual freeing of subtrees: 775 * a) free the subtree starting from *@top 776 * b) free the subtrees whose roots are stored in 777 * (@chain[i].p+1 .. end of @chain[i].bh->b_data) 778 * c) free the subtrees growing from the inode past the @chain[0].p 779 * (no partially truncated stuff there). 780 */ 781 782 static Indirect *ext2_find_shared(struct inode *inode, 783 int depth, 784 int offsets[4], 785 Indirect chain[4], 786 __le32 *top) 787 { 788 Indirect *partial, *p; 789 int k, err; 790 791 *top = 0; 792 for (k = depth; k > 1 && !offsets[k-1]; k--) 793 ; 794 partial = ext2_get_branch(inode, k, offsets, chain, &err); 795 if (!partial) 796 partial = chain + k-1; 797 /* 798 * If the branch acquired continuation since we've looked at it - 799 * fine, it should all survive and (new) top doesn't belong to us. 800 */ 801 write_lock(&EXT2_I(inode)->i_meta_lock); 802 if (!partial->key && *partial->p) { 803 write_unlock(&EXT2_I(inode)->i_meta_lock); 804 goto no_top; 805 } 806 for (p=partial; p>chain && all_zeroes((__le32*)p->bh->b_data,p->p); p--) 807 ; 808 /* 809 * OK, we've found the last block that must survive. The rest of our 810 * branch should be detached before unlocking. However, if that rest 811 * of branch is all ours and does not grow immediately from the inode 812 * it's easier to cheat and just decrement partial->p. 813 */ 814 if (p == chain + k - 1 && p > chain) { 815 p->p--; 816 } else { 817 *top = *p->p; 818 *p->p = 0; 819 } 820 write_unlock(&EXT2_I(inode)->i_meta_lock); 821 822 while(partial > p) 823 { 824 brelse(partial->bh); 825 partial--; 826 } 827 no_top: 828 return partial; 829 } 830 831 /** 832 * ext2_free_data - free a list of data blocks 833 * @inode: inode we are dealing with 834 * @p: array of block numbers 835 * @q: points immediately past the end of array 836 * 837 * We are freeing all blocks refered from that array (numbers are 838 * stored as little-endian 32-bit) and updating @inode->i_blocks 839 * appropriately. 840 */ 841 static inline void ext2_free_data(struct inode *inode, __le32 *p, __le32 *q) 842 { 843 unsigned long block_to_free = 0, count = 0; 844 unsigned long nr; 845 846 for ( ; p < q ; p++) { 847 nr = le32_to_cpu(*p); 848 if (nr) { 849 *p = 0; 850 /* accumulate blocks to free if they're contiguous */ 851 if (count == 0) 852 goto free_this; 853 else if (block_to_free == nr - count) 854 count++; 855 else { 856 mark_inode_dirty(inode); 857 ext2_free_blocks (inode, block_to_free, count); 858 free_this: 859 block_to_free = nr; 860 count = 1; 861 } 862 } 863 } 864 if (count > 0) { 865 mark_inode_dirty(inode); 866 ext2_free_blocks (inode, block_to_free, count); 867 } 868 } 869 870 /** 871 * ext2_free_branches - free an array of branches 872 * @inode: inode we are dealing with 873 * @p: array of block numbers 874 * @q: pointer immediately past the end of array 875 * @depth: depth of the branches to free 876 * 877 * We are freeing all blocks refered from these branches (numbers are 878 * stored as little-endian 32-bit) and updating @inode->i_blocks 879 * appropriately. 880 */ 881 static void ext2_free_branches(struct inode *inode, __le32 *p, __le32 *q, int depth) 882 { 883 struct buffer_head * bh; 884 unsigned long nr; 885 886 if (depth--) { 887 int addr_per_block = EXT2_ADDR_PER_BLOCK(inode->i_sb); 888 for ( ; p < q ; p++) { 889 nr = le32_to_cpu(*p); 890 if (!nr) 891 continue; 892 *p = 0; 893 bh = sb_bread(inode->i_sb, nr); 894 /* 895 * A read failure? Report error and clear slot 896 * (should be rare). 897 */ 898 if (!bh) { 899 ext2_error(inode->i_sb, "ext2_free_branches", 900 "Read failure, inode=%ld, block=%ld", 901 inode->i_ino, nr); 902 continue; 903 } 904 ext2_free_branches(inode, 905 (__le32*)bh->b_data, 906 (__le32*)bh->b_data + addr_per_block, 907 depth); 908 bforget(bh); 909 ext2_free_blocks(inode, nr, 1); 910 mark_inode_dirty(inode); 911 } 912 } else 913 ext2_free_data(inode, p, q); 914 } 915 916 void ext2_truncate (struct inode * inode) 917 { 918 __le32 *i_data = EXT2_I(inode)->i_data; 919 int addr_per_block = EXT2_ADDR_PER_BLOCK(inode->i_sb); 920 int offsets[4]; 921 Indirect chain[4]; 922 Indirect *partial; 923 __le32 nr = 0; 924 int n; 925 long iblock; 926 unsigned blocksize; 927 928 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || 929 S_ISLNK(inode->i_mode))) 930 return; 931 if (ext2_inode_is_fast_symlink(inode)) 932 return; 933 if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) 934 return; 935 936 ext2_discard_prealloc(inode); 937 938 blocksize = inode->i_sb->s_blocksize; 939 iblock = (inode->i_size + blocksize-1) 940 >> EXT2_BLOCK_SIZE_BITS(inode->i_sb); 941 942 if (mapping_is_xip(inode->i_mapping)) 943 xip_truncate_page(inode->i_mapping, inode->i_size); 944 else if (test_opt(inode->i_sb, NOBH)) 945 nobh_truncate_page(inode->i_mapping, 946 inode->i_size, ext2_get_block); 947 else 948 block_truncate_page(inode->i_mapping, 949 inode->i_size, ext2_get_block); 950 951 n = ext2_block_to_path(inode, iblock, offsets, NULL); 952 if (n == 0) 953 return; 954 955 if (n == 1) { 956 ext2_free_data(inode, i_data+offsets[0], 957 i_data + EXT2_NDIR_BLOCKS); 958 goto do_indirects; 959 } 960 961 partial = ext2_find_shared(inode, n, offsets, chain, &nr); 962 /* Kill the top of shared branch (already detached) */ 963 if (nr) { 964 if (partial == chain) 965 mark_inode_dirty(inode); 966 else 967 mark_buffer_dirty_inode(partial->bh, inode); 968 ext2_free_branches(inode, &nr, &nr+1, (chain+n-1) - partial); 969 } 970 /* Clear the ends of indirect blocks on the shared branch */ 971 while (partial > chain) { 972 ext2_free_branches(inode, 973 partial->p + 1, 974 (__le32*)partial->bh->b_data+addr_per_block, 975 (chain+n-1) - partial); 976 mark_buffer_dirty_inode(partial->bh, inode); 977 brelse (partial->bh); 978 partial--; 979 } 980 do_indirects: 981 /* Kill the remaining (whole) subtrees */ 982 switch (offsets[0]) { 983 default: 984 nr = i_data[EXT2_IND_BLOCK]; 985 if (nr) { 986 i_data[EXT2_IND_BLOCK] = 0; 987 mark_inode_dirty(inode); 988 ext2_free_branches(inode, &nr, &nr+1, 1); 989 } 990 case EXT2_IND_BLOCK: 991 nr = i_data[EXT2_DIND_BLOCK]; 992 if (nr) { 993 i_data[EXT2_DIND_BLOCK] = 0; 994 mark_inode_dirty(inode); 995 ext2_free_branches(inode, &nr, &nr+1, 2); 996 } 997 case EXT2_DIND_BLOCK: 998 nr = i_data[EXT2_TIND_BLOCK]; 999 if (nr) { 1000 i_data[EXT2_TIND_BLOCK] = 0; 1001 mark_inode_dirty(inode); 1002 ext2_free_branches(inode, &nr, &nr+1, 3); 1003 } 1004 case EXT2_TIND_BLOCK: 1005 ; 1006 } 1007 inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC; 1008 if (inode_needs_sync(inode)) { 1009 sync_mapping_buffers(inode->i_mapping); 1010 ext2_sync_inode (inode); 1011 } else { 1012 mark_inode_dirty(inode); 1013 } 1014 } 1015 1016 static struct ext2_inode *ext2_get_inode(struct super_block *sb, ino_t ino, 1017 struct buffer_head **p) 1018 { 1019 struct buffer_head * bh; 1020 unsigned long block_group; 1021 unsigned long block; 1022 unsigned long offset; 1023 struct ext2_group_desc * gdp; 1024 1025 *p = NULL; 1026 if ((ino != EXT2_ROOT_INO && ino < EXT2_FIRST_INO(sb)) || 1027 ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) 1028 goto Einval; 1029 1030 block_group = (ino - 1) / EXT2_INODES_PER_GROUP(sb); 1031 gdp = ext2_get_group_desc(sb, block_group, &bh); 1032 if (!gdp) 1033 goto Egdp; 1034 /* 1035 * Figure out the offset within the block group inode table 1036 */ 1037 offset = ((ino - 1) % EXT2_INODES_PER_GROUP(sb)) * EXT2_INODE_SIZE(sb); 1038 block = le32_to_cpu(gdp->bg_inode_table) + 1039 (offset >> EXT2_BLOCK_SIZE_BITS(sb)); 1040 if (!(bh = sb_bread(sb, block))) 1041 goto Eio; 1042 1043 *p = bh; 1044 offset &= (EXT2_BLOCK_SIZE(sb) - 1); 1045 return (struct ext2_inode *) (bh->b_data + offset); 1046 1047 Einval: 1048 ext2_error(sb, "ext2_get_inode", "bad inode number: %lu", 1049 (unsigned long) ino); 1050 return ERR_PTR(-EINVAL); 1051 Eio: 1052 ext2_error(sb, "ext2_get_inode", 1053 "unable to read inode block - inode=%lu, block=%lu", 1054 (unsigned long) ino, block); 1055 Egdp: 1056 return ERR_PTR(-EIO); 1057 } 1058 1059 void ext2_set_inode_flags(struct inode *inode) 1060 { 1061 unsigned int flags = EXT2_I(inode)->i_flags; 1062 1063 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); 1064 if (flags & EXT2_SYNC_FL) 1065 inode->i_flags |= S_SYNC; 1066 if (flags & EXT2_APPEND_FL) 1067 inode->i_flags |= S_APPEND; 1068 if (flags & EXT2_IMMUTABLE_FL) 1069 inode->i_flags |= S_IMMUTABLE; 1070 if (flags & EXT2_NOATIME_FL) 1071 inode->i_flags |= S_NOATIME; 1072 if (flags & EXT2_DIRSYNC_FL) 1073 inode->i_flags |= S_DIRSYNC; 1074 } 1075 1076 /* Propagate flags from i_flags to EXT2_I(inode)->i_flags */ 1077 void ext2_get_inode_flags(struct ext2_inode_info *ei) 1078 { 1079 unsigned int flags = ei->vfs_inode.i_flags; 1080 1081 ei->i_flags &= ~(EXT2_SYNC_FL|EXT2_APPEND_FL| 1082 EXT2_IMMUTABLE_FL|EXT2_NOATIME_FL|EXT2_DIRSYNC_FL); 1083 if (flags & S_SYNC) 1084 ei->i_flags |= EXT2_SYNC_FL; 1085 if (flags & S_APPEND) 1086 ei->i_flags |= EXT2_APPEND_FL; 1087 if (flags & S_IMMUTABLE) 1088 ei->i_flags |= EXT2_IMMUTABLE_FL; 1089 if (flags & S_NOATIME) 1090 ei->i_flags |= EXT2_NOATIME_FL; 1091 if (flags & S_DIRSYNC) 1092 ei->i_flags |= EXT2_DIRSYNC_FL; 1093 } 1094 1095 void ext2_read_inode (struct inode * inode) 1096 { 1097 struct ext2_inode_info *ei = EXT2_I(inode); 1098 ino_t ino = inode->i_ino; 1099 struct buffer_head * bh; 1100 struct ext2_inode * raw_inode = ext2_get_inode(inode->i_sb, ino, &bh); 1101 int n; 1102 1103 #ifdef CONFIG_EXT2_FS_POSIX_ACL 1104 ei->i_acl = EXT2_ACL_NOT_CACHED; 1105 ei->i_default_acl = EXT2_ACL_NOT_CACHED; 1106 #endif 1107 if (IS_ERR(raw_inode)) 1108 goto bad_inode; 1109 1110 inode->i_mode = le16_to_cpu(raw_inode->i_mode); 1111 inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low); 1112 inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low); 1113 if (!(test_opt (inode->i_sb, NO_UID32))) { 1114 inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16; 1115 inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16; 1116 } 1117 inode->i_nlink = le16_to_cpu(raw_inode->i_links_count); 1118 inode->i_size = le32_to_cpu(raw_inode->i_size); 1119 inode->i_atime.tv_sec = (signed)le32_to_cpu(raw_inode->i_atime); 1120 inode->i_ctime.tv_sec = (signed)le32_to_cpu(raw_inode->i_ctime); 1121 inode->i_mtime.tv_sec = (signed)le32_to_cpu(raw_inode->i_mtime); 1122 inode->i_atime.tv_nsec = inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = 0; 1123 ei->i_dtime = le32_to_cpu(raw_inode->i_dtime); 1124 /* We now have enough fields to check if the inode was active or not. 1125 * This is needed because nfsd might try to access dead inodes 1126 * the test is that same one that e2fsck uses 1127 * NeilBrown 1999oct15 1128 */ 1129 if (inode->i_nlink == 0 && (inode->i_mode == 0 || ei->i_dtime)) { 1130 /* this inode is deleted */ 1131 brelse (bh); 1132 goto bad_inode; 1133 } 1134 inode->i_blocks = le32_to_cpu(raw_inode->i_blocks); 1135 ei->i_flags = le32_to_cpu(raw_inode->i_flags); 1136 ei->i_faddr = le32_to_cpu(raw_inode->i_faddr); 1137 ei->i_frag_no = raw_inode->i_frag; 1138 ei->i_frag_size = raw_inode->i_fsize; 1139 ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl); 1140 ei->i_dir_acl = 0; 1141 if (S_ISREG(inode->i_mode)) 1142 inode->i_size |= ((__u64)le32_to_cpu(raw_inode->i_size_high)) << 32; 1143 else 1144 ei->i_dir_acl = le32_to_cpu(raw_inode->i_dir_acl); 1145 ei->i_dtime = 0; 1146 inode->i_generation = le32_to_cpu(raw_inode->i_generation); 1147 ei->i_state = 0; 1148 ei->i_next_alloc_block = 0; 1149 ei->i_next_alloc_goal = 0; 1150 ei->i_prealloc_count = 0; 1151 ei->i_block_group = (ino - 1) / EXT2_INODES_PER_GROUP(inode->i_sb); 1152 ei->i_dir_start_lookup = 0; 1153 1154 /* 1155 * NOTE! The in-memory inode i_data array is in little-endian order 1156 * even on big-endian machines: we do NOT byteswap the block numbers! 1157 */ 1158 for (n = 0; n < EXT2_N_BLOCKS; n++) 1159 ei->i_data[n] = raw_inode->i_block[n]; 1160 1161 if (S_ISREG(inode->i_mode)) { 1162 inode->i_op = &ext2_file_inode_operations; 1163 if (ext2_use_xip(inode->i_sb)) { 1164 inode->i_mapping->a_ops = &ext2_aops_xip; 1165 inode->i_fop = &ext2_xip_file_operations; 1166 } else if (test_opt(inode->i_sb, NOBH)) { 1167 inode->i_mapping->a_ops = &ext2_nobh_aops; 1168 inode->i_fop = &ext2_file_operations; 1169 } else { 1170 inode->i_mapping->a_ops = &ext2_aops; 1171 inode->i_fop = &ext2_file_operations; 1172 } 1173 } else if (S_ISDIR(inode->i_mode)) { 1174 inode->i_op = &ext2_dir_inode_operations; 1175 inode->i_fop = &ext2_dir_operations; 1176 if (test_opt(inode->i_sb, NOBH)) 1177 inode->i_mapping->a_ops = &ext2_nobh_aops; 1178 else 1179 inode->i_mapping->a_ops = &ext2_aops; 1180 } else if (S_ISLNK(inode->i_mode)) { 1181 if (ext2_inode_is_fast_symlink(inode)) 1182 inode->i_op = &ext2_fast_symlink_inode_operations; 1183 else { 1184 inode->i_op = &ext2_symlink_inode_operations; 1185 if (test_opt(inode->i_sb, NOBH)) 1186 inode->i_mapping->a_ops = &ext2_nobh_aops; 1187 else 1188 inode->i_mapping->a_ops = &ext2_aops; 1189 } 1190 } else { 1191 inode->i_op = &ext2_special_inode_operations; 1192 if (raw_inode->i_block[0]) 1193 init_special_inode(inode, inode->i_mode, 1194 old_decode_dev(le32_to_cpu(raw_inode->i_block[0]))); 1195 else 1196 init_special_inode(inode, inode->i_mode, 1197 new_decode_dev(le32_to_cpu(raw_inode->i_block[1]))); 1198 } 1199 brelse (bh); 1200 ext2_set_inode_flags(inode); 1201 return; 1202 1203 bad_inode: 1204 make_bad_inode(inode); 1205 return; 1206 } 1207 1208 static int ext2_update_inode(struct inode * inode, int do_sync) 1209 { 1210 struct ext2_inode_info *ei = EXT2_I(inode); 1211 struct super_block *sb = inode->i_sb; 1212 ino_t ino = inode->i_ino; 1213 uid_t uid = inode->i_uid; 1214 gid_t gid = inode->i_gid; 1215 struct buffer_head * bh; 1216 struct ext2_inode * raw_inode = ext2_get_inode(sb, ino, &bh); 1217 int n; 1218 int err = 0; 1219 1220 if (IS_ERR(raw_inode)) 1221 return -EIO; 1222 1223 /* For fields not not tracking in the in-memory inode, 1224 * initialise them to zero for new inodes. */ 1225 if (ei->i_state & EXT2_STATE_NEW) 1226 memset(raw_inode, 0, EXT2_SB(sb)->s_inode_size); 1227 1228 ext2_get_inode_flags(ei); 1229 raw_inode->i_mode = cpu_to_le16(inode->i_mode); 1230 if (!(test_opt(sb, NO_UID32))) { 1231 raw_inode->i_uid_low = cpu_to_le16(low_16_bits(uid)); 1232 raw_inode->i_gid_low = cpu_to_le16(low_16_bits(gid)); 1233 /* 1234 * Fix up interoperability with old kernels. Otherwise, old inodes get 1235 * re-used with the upper 16 bits of the uid/gid intact 1236 */ 1237 if (!ei->i_dtime) { 1238 raw_inode->i_uid_high = cpu_to_le16(high_16_bits(uid)); 1239 raw_inode->i_gid_high = cpu_to_le16(high_16_bits(gid)); 1240 } else { 1241 raw_inode->i_uid_high = 0; 1242 raw_inode->i_gid_high = 0; 1243 } 1244 } else { 1245 raw_inode->i_uid_low = cpu_to_le16(fs_high2lowuid(uid)); 1246 raw_inode->i_gid_low = cpu_to_le16(fs_high2lowgid(gid)); 1247 raw_inode->i_uid_high = 0; 1248 raw_inode->i_gid_high = 0; 1249 } 1250 raw_inode->i_links_count = cpu_to_le16(inode->i_nlink); 1251 raw_inode->i_size = cpu_to_le32(inode->i_size); 1252 raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec); 1253 raw_inode->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); 1254 raw_inode->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); 1255 1256 raw_inode->i_blocks = cpu_to_le32(inode->i_blocks); 1257 raw_inode->i_dtime = cpu_to_le32(ei->i_dtime); 1258 raw_inode->i_flags = cpu_to_le32(ei->i_flags); 1259 raw_inode->i_faddr = cpu_to_le32(ei->i_faddr); 1260 raw_inode->i_frag = ei->i_frag_no; 1261 raw_inode->i_fsize = ei->i_frag_size; 1262 raw_inode->i_file_acl = cpu_to_le32(ei->i_file_acl); 1263 if (!S_ISREG(inode->i_mode)) 1264 raw_inode->i_dir_acl = cpu_to_le32(ei->i_dir_acl); 1265 else { 1266 raw_inode->i_size_high = cpu_to_le32(inode->i_size >> 32); 1267 if (inode->i_size > 0x7fffffffULL) { 1268 if (!EXT2_HAS_RO_COMPAT_FEATURE(sb, 1269 EXT2_FEATURE_RO_COMPAT_LARGE_FILE) || 1270 EXT2_SB(sb)->s_es->s_rev_level == 1271 cpu_to_le32(EXT2_GOOD_OLD_REV)) { 1272 /* If this is the first large file 1273 * created, add a flag to the superblock. 1274 */ 1275 lock_kernel(); 1276 ext2_update_dynamic_rev(sb); 1277 EXT2_SET_RO_COMPAT_FEATURE(sb, 1278 EXT2_FEATURE_RO_COMPAT_LARGE_FILE); 1279 unlock_kernel(); 1280 ext2_write_super(sb); 1281 } 1282 } 1283 } 1284 1285 raw_inode->i_generation = cpu_to_le32(inode->i_generation); 1286 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { 1287 if (old_valid_dev(inode->i_rdev)) { 1288 raw_inode->i_block[0] = 1289 cpu_to_le32(old_encode_dev(inode->i_rdev)); 1290 raw_inode->i_block[1] = 0; 1291 } else { 1292 raw_inode->i_block[0] = 0; 1293 raw_inode->i_block[1] = 1294 cpu_to_le32(new_encode_dev(inode->i_rdev)); 1295 raw_inode->i_block[2] = 0; 1296 } 1297 } else for (n = 0; n < EXT2_N_BLOCKS; n++) 1298 raw_inode->i_block[n] = ei->i_data[n]; 1299 mark_buffer_dirty(bh); 1300 if (do_sync) { 1301 sync_dirty_buffer(bh); 1302 if (buffer_req(bh) && !buffer_uptodate(bh)) { 1303 printk ("IO error syncing ext2 inode [%s:%08lx]\n", 1304 sb->s_id, (unsigned long) ino); 1305 err = -EIO; 1306 } 1307 } 1308 ei->i_state &= ~EXT2_STATE_NEW; 1309 brelse (bh); 1310 return err; 1311 } 1312 1313 int ext2_write_inode(struct inode *inode, int wait) 1314 { 1315 return ext2_update_inode(inode, wait); 1316 } 1317 1318 int ext2_sync_inode(struct inode *inode) 1319 { 1320 struct writeback_control wbc = { 1321 .sync_mode = WB_SYNC_ALL, 1322 .nr_to_write = 0, /* sys_fsync did this */ 1323 }; 1324 return sync_inode(inode, &wbc); 1325 } 1326 1327 int ext2_setattr(struct dentry *dentry, struct iattr *iattr) 1328 { 1329 struct inode *inode = dentry->d_inode; 1330 int error; 1331 1332 error = inode_change_ok(inode, iattr); 1333 if (error) 1334 return error; 1335 if ((iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) || 1336 (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid)) { 1337 error = DQUOT_TRANSFER(inode, iattr) ? -EDQUOT : 0; 1338 if (error) 1339 return error; 1340 } 1341 error = inode_setattr(inode, iattr); 1342 if (!error && (iattr->ia_valid & ATTR_MODE)) 1343 error = ext2_acl_chmod(inode); 1344 return error; 1345 } 1346