1/* 2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. 3 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. 4 * 5 * This copyrighted material is made available to anyone wishing to use, 6 * modify, copy, or redistribute it subject to the terms and conditions 7 * of the GNU General Public License version 2. 8 */ 9 10#include <linux/spinlock.h> 11#include <linux/completion.h> 12#include <linux/buffer_head.h> 13#include <linux/blkdev.h> 14#include <linux/gfs2_ondisk.h> 15#include <linux/crc32.h> 16 17#include "gfs2.h" 18#include "incore.h" 19#include "bmap.h" 20#include "glock.h" 21#include "inode.h" 22#include "meta_io.h" 23#include "quota.h" 24#include "rgrp.h" 25#include "log.h" 26#include "super.h" 27#include "trans.h" 28#include "dir.h" 29#include "util.h" 30#include "trace_gfs2.h" 31 32/* This doesn't need to be that large as max 64 bit pointers in a 4k 33 * block is 512, so __u16 is fine for that. It saves stack space to 34 * keep it small. 35 */ 36struct metapath { 37 struct buffer_head *mp_bh[GFS2_MAX_META_HEIGHT]; 38 __u16 mp_list[GFS2_MAX_META_HEIGHT]; 39}; 40 41struct strip_mine { 42 int sm_first; 43 unsigned int sm_height; 44}; 45 46/** 47 * gfs2_unstuffer_page - unstuff a stuffed inode into a block cached by a page 48 * @ip: the inode 49 * @dibh: the dinode buffer 50 * @block: the block number that was allocated 51 * @page: The (optional) page. This is looked up if @page is NULL 52 * 53 * Returns: errno 54 */ 55 56static int gfs2_unstuffer_page(struct gfs2_inode *ip, struct buffer_head *dibh, 57 u64 block, struct page *page) 58{ 59 struct inode *inode = &ip->i_inode; 60 struct buffer_head *bh; 61 int release = 0; 62 63 if (!page || page->index) { 64 page = find_or_create_page(inode->i_mapping, 0, GFP_NOFS); 65 if (!page) 66 return -ENOMEM; 67 release = 1; 68 } 69 70 if (!PageUptodate(page)) { 71 void *kaddr = kmap(page); 72 u64 dsize = i_size_read(inode); 73 74 if (dsize > (dibh->b_size - sizeof(struct gfs2_dinode))) 75 dsize = dibh->b_size - sizeof(struct gfs2_dinode); 76 77 memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), dsize); 78 memset(kaddr + dsize, 0, PAGE_CACHE_SIZE - dsize); 79 kunmap(page); 80 81 SetPageUptodate(page); 82 } 83 84 if (!page_has_buffers(page)) 85 create_empty_buffers(page, 1 << inode->i_blkbits, 86 (1 << BH_Uptodate)); 87 88 bh = page_buffers(page); 89 90 if (!buffer_mapped(bh)) 91 map_bh(bh, inode->i_sb, block); 92 93 set_buffer_uptodate(bh); 94 if (!gfs2_is_jdata(ip)) 95 mark_buffer_dirty(bh); 96 if (!gfs2_is_writeback(ip)) 97 gfs2_trans_add_data(ip->i_gl, bh); 98 99 if (release) { 100 unlock_page(page); 101 page_cache_release(page); 102 } 103 104 return 0; 105} 106 107/** 108 * gfs2_unstuff_dinode - Unstuff a dinode when the data has grown too big 109 * @ip: The GFS2 inode to unstuff 110 * @page: The (optional) page. This is looked up if the @page is NULL 111 * 112 * This routine unstuffs a dinode and returns it to a "normal" state such 113 * that the height can be grown in the traditional way. 114 * 115 * Returns: errno 116 */ 117 118int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page) 119{ 120 struct buffer_head *bh, *dibh; 121 struct gfs2_dinode *di; 122 u64 block = 0; 123 int isdir = gfs2_is_dir(ip); 124 int error; 125 126 down_write(&ip->i_rw_mutex); 127 128 error = gfs2_meta_inode_buffer(ip, &dibh); 129 if (error) 130 goto out; 131 132 if (i_size_read(&ip->i_inode)) { 133 /* Get a free block, fill it with the stuffed data, 134 and write it out to disk */ 135 136 unsigned int n = 1; 137 error = gfs2_alloc_blocks(ip, &block, &n, 0, NULL); 138 if (error) 139 goto out_brelse; 140 if (isdir) { 141 gfs2_trans_add_unrevoke(GFS2_SB(&ip->i_inode), block, 1); 142 error = gfs2_dir_get_new_buffer(ip, block, &bh); 143 if (error) 144 goto out_brelse; 145 gfs2_buffer_copy_tail(bh, sizeof(struct gfs2_meta_header), 146 dibh, sizeof(struct gfs2_dinode)); 147 brelse(bh); 148 } else { 149 error = gfs2_unstuffer_page(ip, dibh, block, page); 150 if (error) 151 goto out_brelse; 152 } 153 } 154 155 /* Set up the pointer to the new block */ 156 157 gfs2_trans_add_meta(ip->i_gl, dibh); 158 di = (struct gfs2_dinode *)dibh->b_data; 159 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode)); 160 161 if (i_size_read(&ip->i_inode)) { 162 *(__be64 *)(di + 1) = cpu_to_be64(block); 163 gfs2_add_inode_blocks(&ip->i_inode, 1); 164 di->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode)); 165 } 166 167 ip->i_height = 1; 168 di->di_height = cpu_to_be16(1); 169 170out_brelse: 171 brelse(dibh); 172out: 173 up_write(&ip->i_rw_mutex); 174 return error; 175} 176 177 178/** 179 * find_metapath - Find path through the metadata tree 180 * @sdp: The superblock 181 * @mp: The metapath to return the result in 182 * @block: The disk block to look up 183 * @height: The pre-calculated height of the metadata tree 184 * 185 * This routine returns a struct metapath structure that defines a path 186 * through the metadata of inode "ip" to get to block "block". 187 * 188 * Example: 189 * Given: "ip" is a height 3 file, "offset" is 101342453, and this is a 190 * filesystem with a blocksize of 4096. 191 * 192 * find_metapath() would return a struct metapath structure set to: 193 * mp_offset = 101342453, mp_height = 3, mp_list[0] = 0, mp_list[1] = 48, 194 * and mp_list[2] = 165. 195 * 196 * That means that in order to get to the block containing the byte at 197 * offset 101342453, we would load the indirect block pointed to by pointer 198 * 0 in the dinode. We would then load the indirect block pointed to by 199 * pointer 48 in that indirect block. We would then load the data block 200 * pointed to by pointer 165 in that indirect block. 201 * 202 * ---------------------------------------- 203 * | Dinode | | 204 * | | 4| 205 * | |0 1 2 3 4 5 9| 206 * | | 6| 207 * ---------------------------------------- 208 * | 209 * | 210 * V 211 * ---------------------------------------- 212 * | Indirect Block | 213 * | 5| 214 * | 4 4 4 4 4 5 5 1| 215 * |0 5 6 7 8 9 0 1 2| 216 * ---------------------------------------- 217 * | 218 * | 219 * V 220 * ---------------------------------------- 221 * | Indirect Block | 222 * | 1 1 1 1 1 5| 223 * | 6 6 6 6 6 1| 224 * |0 3 4 5 6 7 2| 225 * ---------------------------------------- 226 * | 227 * | 228 * V 229 * ---------------------------------------- 230 * | Data block containing offset | 231 * | 101342453 | 232 * | | 233 * | | 234 * ---------------------------------------- 235 * 236 */ 237 238static void find_metapath(const struct gfs2_sbd *sdp, u64 block, 239 struct metapath *mp, unsigned int height) 240{ 241 unsigned int i; 242 243 for (i = height; i--;) 244 mp->mp_list[i] = do_div(block, sdp->sd_inptrs); 245 246} 247 248static inline unsigned int metapath_branch_start(const struct metapath *mp) 249{ 250 if (mp->mp_list[0] == 0) 251 return 2; 252 return 1; 253} 254 255/** 256 * metapointer - Return pointer to start of metadata in a buffer 257 * @height: The metadata height (0 = dinode) 258 * @mp: The metapath 259 * 260 * Return a pointer to the block number of the next height of the metadata 261 * tree given a buffer containing the pointer to the current height of the 262 * metadata tree. 263 */ 264 265static inline __be64 *metapointer(unsigned int height, const struct metapath *mp) 266{ 267 struct buffer_head *bh = mp->mp_bh[height]; 268 unsigned int head_size = (height > 0) ? 269 sizeof(struct gfs2_meta_header) : sizeof(struct gfs2_dinode); 270 return ((__be64 *)(bh->b_data + head_size)) + mp->mp_list[height]; 271} 272 273static void gfs2_metapath_ra(struct gfs2_glock *gl, 274 const struct buffer_head *bh, const __be64 *pos) 275{ 276 struct buffer_head *rabh; 277 const __be64 *endp = (const __be64 *)(bh->b_data + bh->b_size); 278 const __be64 *t; 279 280 for (t = pos; t < endp; t++) { 281 if (!*t) 282 continue; 283 284 rabh = gfs2_getbuf(gl, be64_to_cpu(*t), CREATE); 285 if (trylock_buffer(rabh)) { 286 if (!buffer_uptodate(rabh)) { 287 rabh->b_end_io = end_buffer_read_sync; 288 submit_bh(READA | REQ_META, rabh); 289 continue; 290 } 291 unlock_buffer(rabh); 292 } 293 brelse(rabh); 294 } 295} 296 297/** 298 * lookup_metapath - Walk the metadata tree to a specific point 299 * @ip: The inode 300 * @mp: The metapath 301 * 302 * Assumes that the inode's buffer has already been looked up and 303 * hooked onto mp->mp_bh[0] and that the metapath has been initialised 304 * by find_metapath(). 305 * 306 * If this function encounters part of the tree which has not been 307 * allocated, it returns the current height of the tree at the point 308 * at which it found the unallocated block. Blocks which are found are 309 * added to the mp->mp_bh[] list. 310 * 311 * Returns: error or height of metadata tree 312 */ 313 314static int lookup_metapath(struct gfs2_inode *ip, struct metapath *mp) 315{ 316 unsigned int end_of_metadata = ip->i_height - 1; 317 unsigned int x; 318 __be64 *ptr; 319 u64 dblock; 320 int ret; 321 322 for (x = 0; x < end_of_metadata; x++) { 323 ptr = metapointer(x, mp); 324 dblock = be64_to_cpu(*ptr); 325 if (!dblock) 326 return x + 1; 327 328 ret = gfs2_meta_indirect_buffer(ip, x+1, dblock, &mp->mp_bh[x+1]); 329 if (ret) 330 return ret; 331 } 332 333 return ip->i_height; 334} 335 336static inline void release_metapath(struct metapath *mp) 337{ 338 int i; 339 340 for (i = 0; i < GFS2_MAX_META_HEIGHT; i++) { 341 if (mp->mp_bh[i] == NULL) 342 break; 343 brelse(mp->mp_bh[i]); 344 } 345} 346 347/** 348 * gfs2_extent_length - Returns length of an extent of blocks 349 * @start: Start of the buffer 350 * @len: Length of the buffer in bytes 351 * @ptr: Current position in the buffer 352 * @limit: Max extent length to return (0 = unlimited) 353 * @eob: Set to 1 if we hit "end of block" 354 * 355 * If the first block is zero (unallocated) it will return the number of 356 * unallocated blocks in the extent, otherwise it will return the number 357 * of contiguous blocks in the extent. 358 * 359 * Returns: The length of the extent (minimum of one block) 360 */ 361 362static inline unsigned int gfs2_extent_length(void *start, unsigned int len, __be64 *ptr, size_t limit, int *eob) 363{ 364 const __be64 *end = (start + len); 365 const __be64 *first = ptr; 366 u64 d = be64_to_cpu(*ptr); 367 368 *eob = 0; 369 do { 370 ptr++; 371 if (ptr >= end) 372 break; 373 if (limit && --limit == 0) 374 break; 375 if (d) 376 d++; 377 } while(be64_to_cpu(*ptr) == d); 378 if (ptr >= end) 379 *eob = 1; 380 return (ptr - first); 381} 382 383static inline void bmap_lock(struct gfs2_inode *ip, int create) 384{ 385 if (create) 386 down_write(&ip->i_rw_mutex); 387 else 388 down_read(&ip->i_rw_mutex); 389} 390 391static inline void bmap_unlock(struct gfs2_inode *ip, int create) 392{ 393 if (create) 394 up_write(&ip->i_rw_mutex); 395 else 396 up_read(&ip->i_rw_mutex); 397} 398 399static inline __be64 *gfs2_indirect_init(struct metapath *mp, 400 struct gfs2_glock *gl, unsigned int i, 401 unsigned offset, u64 bn) 402{ 403 __be64 *ptr = (__be64 *)(mp->mp_bh[i - 1]->b_data + 404 ((i > 1) ? sizeof(struct gfs2_meta_header) : 405 sizeof(struct gfs2_dinode))); 406 BUG_ON(i < 1); 407 BUG_ON(mp->mp_bh[i] != NULL); 408 mp->mp_bh[i] = gfs2_meta_new(gl, bn); 409 gfs2_trans_add_meta(gl, mp->mp_bh[i]); 410 gfs2_metatype_set(mp->mp_bh[i], GFS2_METATYPE_IN, GFS2_FORMAT_IN); 411 gfs2_buffer_clear_tail(mp->mp_bh[i], sizeof(struct gfs2_meta_header)); 412 ptr += offset; 413 *ptr = cpu_to_be64(bn); 414 return ptr; 415} 416 417enum alloc_state { 418 ALLOC_DATA = 0, 419 ALLOC_GROW_DEPTH = 1, 420 ALLOC_GROW_HEIGHT = 2, 421 /* ALLOC_UNSTUFF = 3, TBD and rather complicated */ 422}; 423 424/** 425 * gfs2_bmap_alloc - Build a metadata tree of the requested height 426 * @inode: The GFS2 inode 427 * @lblock: The logical starting block of the extent 428 * @bh_map: This is used to return the mapping details 429 * @mp: The metapath 430 * @sheight: The starting height (i.e. whats already mapped) 431 * @height: The height to build to 432 * @maxlen: The max number of data blocks to alloc 433 * 434 * In this routine we may have to alloc: 435 * i) Indirect blocks to grow the metadata tree height 436 * ii) Indirect blocks to fill in lower part of the metadata tree 437 * iii) Data blocks 438 * 439 * The function is in two parts. The first part works out the total 440 * number of blocks which we need. The second part does the actual 441 * allocation asking for an extent at a time (if enough contiguous free 442 * blocks are available, there will only be one request per bmap call) 443 * and uses the state machine to initialise the blocks in order. 444 * 445 * Returns: errno on error 446 */ 447 448static int gfs2_bmap_alloc(struct inode *inode, const sector_t lblock, 449 struct buffer_head *bh_map, struct metapath *mp, 450 const unsigned int sheight, 451 const unsigned int height, 452 const size_t maxlen) 453{ 454 struct gfs2_inode *ip = GFS2_I(inode); 455 struct gfs2_sbd *sdp = GFS2_SB(inode); 456 struct super_block *sb = sdp->sd_vfs; 457 struct buffer_head *dibh = mp->mp_bh[0]; 458 u64 bn, dblock = 0; 459 unsigned n, i, blks, alloced = 0, iblks = 0, branch_start = 0; 460 unsigned dblks = 0; 461 unsigned ptrs_per_blk; 462 const unsigned end_of_metadata = height - 1; 463 int ret; 464 int eob = 0; 465 enum alloc_state state; 466 __be64 *ptr; 467 __be64 zero_bn = 0; 468 469 BUG_ON(sheight < 1); 470 BUG_ON(dibh == NULL); 471 472 gfs2_trans_add_meta(ip->i_gl, dibh); 473 474 if (height == sheight) { 475 struct buffer_head *bh; 476 /* Bottom indirect block exists, find unalloced extent size */ 477 ptr = metapointer(end_of_metadata, mp); 478 bh = mp->mp_bh[end_of_metadata]; 479 dblks = gfs2_extent_length(bh->b_data, bh->b_size, ptr, maxlen, 480 &eob); 481 BUG_ON(dblks < 1); 482 state = ALLOC_DATA; 483 } else { 484 /* Need to allocate indirect blocks */ 485 ptrs_per_blk = height > 1 ? sdp->sd_inptrs : sdp->sd_diptrs; 486 dblks = min(maxlen, (size_t)(ptrs_per_blk - 487 mp->mp_list[end_of_metadata])); 488 if (height == ip->i_height) { 489 /* Writing into existing tree, extend tree down */ 490 iblks = height - sheight; 491 state = ALLOC_GROW_DEPTH; 492 } else { 493 /* Building up tree height */ 494 state = ALLOC_GROW_HEIGHT; 495 iblks = height - ip->i_height; 496 branch_start = metapath_branch_start(mp); 497 iblks += (height - branch_start); 498 } 499 } 500 501 /* start of the second part of the function (state machine) */ 502 503 blks = dblks + iblks; 504 i = sheight; 505 do { 506 int error; 507 n = blks - alloced; 508 error = gfs2_alloc_blocks(ip, &bn, &n, 0, NULL); 509 if (error) 510 return error; 511 alloced += n; 512 if (state != ALLOC_DATA || gfs2_is_jdata(ip)) 513 gfs2_trans_add_unrevoke(sdp, bn, n); 514 switch (state) { 515 /* Growing height of tree */ 516 case ALLOC_GROW_HEIGHT: 517 if (i == 1) { 518 ptr = (__be64 *)(dibh->b_data + 519 sizeof(struct gfs2_dinode)); 520 zero_bn = *ptr; 521 } 522 for (; i - 1 < height - ip->i_height && n > 0; i++, n--) 523 gfs2_indirect_init(mp, ip->i_gl, i, 0, bn++); 524 if (i - 1 == height - ip->i_height) { 525 i--; 526 gfs2_buffer_copy_tail(mp->mp_bh[i], 527 sizeof(struct gfs2_meta_header), 528 dibh, sizeof(struct gfs2_dinode)); 529 gfs2_buffer_clear_tail(dibh, 530 sizeof(struct gfs2_dinode) + 531 sizeof(__be64)); 532 ptr = (__be64 *)(mp->mp_bh[i]->b_data + 533 sizeof(struct gfs2_meta_header)); 534 *ptr = zero_bn; 535 state = ALLOC_GROW_DEPTH; 536 for(i = branch_start; i < height; i++) { 537 if (mp->mp_bh[i] == NULL) 538 break; 539 brelse(mp->mp_bh[i]); 540 mp->mp_bh[i] = NULL; 541 } 542 i = branch_start; 543 } 544 if (n == 0) 545 break; 546 /* Branching from existing tree */ 547 case ALLOC_GROW_DEPTH: 548 if (i > 1 && i < height) 549 gfs2_trans_add_meta(ip->i_gl, mp->mp_bh[i-1]); 550 for (; i < height && n > 0; i++, n--) 551 gfs2_indirect_init(mp, ip->i_gl, i, 552 mp->mp_list[i-1], bn++); 553 if (i == height) 554 state = ALLOC_DATA; 555 if (n == 0) 556 break; 557 /* Tree complete, adding data blocks */ 558 case ALLOC_DATA: 559 BUG_ON(n > dblks); 560 BUG_ON(mp->mp_bh[end_of_metadata] == NULL); 561 gfs2_trans_add_meta(ip->i_gl, mp->mp_bh[end_of_metadata]); 562 dblks = n; 563 ptr = metapointer(end_of_metadata, mp); 564 dblock = bn; 565 while (n-- > 0) 566 *ptr++ = cpu_to_be64(bn++); 567 if (buffer_zeronew(bh_map)) { 568 ret = sb_issue_zeroout(sb, dblock, dblks, 569 GFP_NOFS); 570 if (ret) { 571 fs_err(sdp, 572 "Failed to zero data buffers\n"); 573 clear_buffer_zeronew(bh_map); 574 } 575 } 576 break; 577 } 578 } while ((state != ALLOC_DATA) || !dblock); 579 580 ip->i_height = height; 581 gfs2_add_inode_blocks(&ip->i_inode, alloced); 582 gfs2_dinode_out(ip, mp->mp_bh[0]->b_data); 583 map_bh(bh_map, inode->i_sb, dblock); 584 bh_map->b_size = dblks << inode->i_blkbits; 585 set_buffer_new(bh_map); 586 return 0; 587} 588 589/** 590 * gfs2_block_map - Map a block from an inode to a disk block 591 * @inode: The inode 592 * @lblock: The logical block number 593 * @bh_map: The bh to be mapped 594 * @create: True if its ok to alloc blocks to satify the request 595 * 596 * Sets buffer_mapped() if successful, sets buffer_boundary() if a 597 * read of metadata will be required before the next block can be 598 * mapped. Sets buffer_new() if new blocks were allocated. 599 * 600 * Returns: errno 601 */ 602 603int gfs2_block_map(struct inode *inode, sector_t lblock, 604 struct buffer_head *bh_map, int create) 605{ 606 struct gfs2_inode *ip = GFS2_I(inode); 607 struct gfs2_sbd *sdp = GFS2_SB(inode); 608 unsigned int bsize = sdp->sd_sb.sb_bsize; 609 const size_t maxlen = bh_map->b_size >> inode->i_blkbits; 610 const u64 *arr = sdp->sd_heightsize; 611 __be64 *ptr; 612 u64 size; 613 struct metapath mp; 614 int ret; 615 int eob; 616 unsigned int len; 617 struct buffer_head *bh; 618 u8 height; 619 620 BUG_ON(maxlen == 0); 621 622 memset(mp.mp_bh, 0, sizeof(mp.mp_bh)); 623 bmap_lock(ip, create); 624 clear_buffer_mapped(bh_map); 625 clear_buffer_new(bh_map); 626 clear_buffer_boundary(bh_map); 627 trace_gfs2_bmap(ip, bh_map, lblock, create, 1); 628 if (gfs2_is_dir(ip)) { 629 bsize = sdp->sd_jbsize; 630 arr = sdp->sd_jheightsize; 631 } 632 633 ret = gfs2_meta_inode_buffer(ip, &mp.mp_bh[0]); 634 if (ret) 635 goto out; 636 637 height = ip->i_height; 638 size = (lblock + 1) * bsize; 639 while (size > arr[height]) 640 height++; 641 find_metapath(sdp, lblock, &mp, height); 642 ret = 1; 643 if (height > ip->i_height || gfs2_is_stuffed(ip)) 644 goto do_alloc; 645 ret = lookup_metapath(ip, &mp); 646 if (ret < 0) 647 goto out; 648 if (ret != ip->i_height) 649 goto do_alloc; 650 ptr = metapointer(ip->i_height - 1, &mp); 651 if (*ptr == 0) 652 goto do_alloc; 653 map_bh(bh_map, inode->i_sb, be64_to_cpu(*ptr)); 654 bh = mp.mp_bh[ip->i_height - 1]; 655 len = gfs2_extent_length(bh->b_data, bh->b_size, ptr, maxlen, &eob); 656 bh_map->b_size = (len << inode->i_blkbits); 657 if (eob) 658 set_buffer_boundary(bh_map); 659 ret = 0; 660out: 661 release_metapath(&mp); 662 trace_gfs2_bmap(ip, bh_map, lblock, create, ret); 663 bmap_unlock(ip, create); 664 return ret; 665 666do_alloc: 667 /* All allocations are done here, firstly check create flag */ 668 if (!create) { 669 BUG_ON(gfs2_is_stuffed(ip)); 670 ret = 0; 671 goto out; 672 } 673 674 /* At this point ret is the tree depth of already allocated blocks */ 675 ret = gfs2_bmap_alloc(inode, lblock, bh_map, &mp, ret, height, maxlen); 676 goto out; 677} 678 679/* 680 * Deprecated: do not use in new code 681 */ 682int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen) 683{ 684 struct buffer_head bh = { .b_state = 0, .b_blocknr = 0 }; 685 int ret; 686 int create = *new; 687 688 BUG_ON(!extlen); 689 BUG_ON(!dblock); 690 BUG_ON(!new); 691 692 bh.b_size = 1 << (inode->i_blkbits + (create ? 0 : 5)); 693 ret = gfs2_block_map(inode, lblock, &bh, create); 694 *extlen = bh.b_size >> inode->i_blkbits; 695 *dblock = bh.b_blocknr; 696 if (buffer_new(&bh)) 697 *new = 1; 698 else 699 *new = 0; 700 return ret; 701} 702 703/** 704 * do_strip - Look for a layer a particular layer of the file and strip it off 705 * @ip: the inode 706 * @dibh: the dinode buffer 707 * @bh: A buffer of pointers 708 * @top: The first pointer in the buffer 709 * @bottom: One more than the last pointer 710 * @height: the height this buffer is at 711 * @sm: a pointer to a struct strip_mine 712 * 713 * Returns: errno 714 */ 715 716static int do_strip(struct gfs2_inode *ip, struct buffer_head *dibh, 717 struct buffer_head *bh, __be64 *top, __be64 *bottom, 718 unsigned int height, struct strip_mine *sm) 719{ 720 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); 721 struct gfs2_rgrp_list rlist; 722 u64 bn, bstart; 723 u32 blen, btotal; 724 __be64 *p; 725 unsigned int rg_blocks = 0; 726 int metadata; 727 unsigned int revokes = 0; 728 int x; 729 int error; 730 731 error = gfs2_rindex_update(sdp); 732 if (error) 733 return error; 734 735 if (!*top) 736 sm->sm_first = 0; 737 738 if (height != sm->sm_height) 739 return 0; 740 741 if (sm->sm_first) { 742 top++; 743 sm->sm_first = 0; 744 } 745 746 metadata = (height != ip->i_height - 1); 747 if (metadata) 748 revokes = (height) ? sdp->sd_inptrs : sdp->sd_diptrs; 749 else if (ip->i_depth) 750 revokes = sdp->sd_inptrs; 751 752 memset(&rlist, 0, sizeof(struct gfs2_rgrp_list)); 753 bstart = 0; 754 blen = 0; 755 756 for (p = top; p < bottom; p++) { 757 if (!*p) 758 continue; 759 760 bn = be64_to_cpu(*p); 761 762 if (bstart + blen == bn) 763 blen++; 764 else { 765 if (bstart) 766 gfs2_rlist_add(ip, &rlist, bstart); 767 768 bstart = bn; 769 blen = 1; 770 } 771 } 772 773 if (bstart) 774 gfs2_rlist_add(ip, &rlist, bstart); 775 else 776 goto out; /* Nothing to do */ 777 778 gfs2_rlist_alloc(&rlist, LM_ST_EXCLUSIVE); 779 780 for (x = 0; x < rlist.rl_rgrps; x++) { 781 struct gfs2_rgrpd *rgd; 782 rgd = rlist.rl_ghs[x].gh_gl->gl_object; 783 rg_blocks += rgd->rd_length; 784 } 785 786 error = gfs2_glock_nq_m(rlist.rl_rgrps, rlist.rl_ghs); 787 if (error) 788 goto out_rlist; 789 790 if (gfs2_rs_active(ip->i_res)) /* needs to be done with the rgrp glock held */ 791 gfs2_rs_deltree(ip->i_res); 792 793 error = gfs2_trans_begin(sdp, rg_blocks + RES_DINODE + 794 RES_INDIRECT + RES_STATFS + RES_QUOTA, 795 revokes); 796 if (error) 797 goto out_rg_gunlock; 798 799 down_write(&ip->i_rw_mutex); 800 801 gfs2_trans_add_meta(ip->i_gl, dibh); 802 gfs2_trans_add_meta(ip->i_gl, bh); 803 804 bstart = 0; 805 blen = 0; 806 btotal = 0; 807 808 for (p = top; p < bottom; p++) { 809 if (!*p) 810 continue; 811 812 bn = be64_to_cpu(*p); 813 814 if (bstart + blen == bn) 815 blen++; 816 else { 817 if (bstart) { 818 __gfs2_free_blocks(ip, bstart, blen, metadata); 819 btotal += blen; 820 } 821 822 bstart = bn; 823 blen = 1; 824 } 825 826 *p = 0; 827 gfs2_add_inode_blocks(&ip->i_inode, -1); 828 } 829 if (bstart) { 830 __gfs2_free_blocks(ip, bstart, blen, metadata); 831 btotal += blen; 832 } 833 834 gfs2_statfs_change(sdp, 0, +btotal, 0); 835 gfs2_quota_change(ip, -(s64)btotal, ip->i_inode.i_uid, 836 ip->i_inode.i_gid); 837 838 ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME; 839 840 gfs2_dinode_out(ip, dibh->b_data); 841 842 up_write(&ip->i_rw_mutex); 843 844 gfs2_trans_end(sdp); 845 846out_rg_gunlock: 847 gfs2_glock_dq_m(rlist.rl_rgrps, rlist.rl_ghs); 848out_rlist: 849 gfs2_rlist_free(&rlist); 850out: 851 return error; 852} 853 854/** 855 * recursive_scan - recursively scan through the end of a file 856 * @ip: the inode 857 * @dibh: the dinode buffer 858 * @mp: the path through the metadata to the point to start 859 * @height: the height the recursion is at 860 * @block: the indirect block to look at 861 * @first: 1 if this is the first block 862 * @sm: data opaque to this function to pass to @bc 863 * 864 * When this is first called @height and @block should be zero and 865 * @first should be 1. 866 * 867 * Returns: errno 868 */ 869 870static int recursive_scan(struct gfs2_inode *ip, struct buffer_head *dibh, 871 struct metapath *mp, unsigned int height, 872 u64 block, int first, struct strip_mine *sm) 873{ 874 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); 875 struct buffer_head *bh = NULL; 876 __be64 *top, *bottom; 877 u64 bn; 878 int error; 879 int mh_size = sizeof(struct gfs2_meta_header); 880 881 if (!height) { 882 error = gfs2_meta_inode_buffer(ip, &bh); 883 if (error) 884 return error; 885 dibh = bh; 886 887 top = (__be64 *)(bh->b_data + sizeof(struct gfs2_dinode)) + mp->mp_list[0]; 888 bottom = (__be64 *)(bh->b_data + sizeof(struct gfs2_dinode)) + sdp->sd_diptrs; 889 } else { 890 error = gfs2_meta_indirect_buffer(ip, height, block, &bh); 891 if (error) 892 return error; 893 894 top = (__be64 *)(bh->b_data + mh_size) + 895 (first ? mp->mp_list[height] : 0); 896 897 bottom = (__be64 *)(bh->b_data + mh_size) + sdp->sd_inptrs; 898 } 899 900 error = do_strip(ip, dibh, bh, top, bottom, height, sm); 901 if (error) 902 goto out; 903 904 if (height < ip->i_height - 1) { 905 906 gfs2_metapath_ra(ip->i_gl, bh, top); 907 908 for (; top < bottom; top++, first = 0) { 909 if (!*top) 910 continue; 911 912 bn = be64_to_cpu(*top); 913 914 error = recursive_scan(ip, dibh, mp, height + 1, bn, 915 first, sm); 916 if (error) 917 break; 918 } 919 } 920out: 921 brelse(bh); 922 return error; 923} 924 925 926/** 927 * gfs2_block_truncate_page - Deal with zeroing out data for truncate 928 * 929 * This is partly borrowed from ext3. 930 */ 931static int gfs2_block_truncate_page(struct address_space *mapping, loff_t from) 932{ 933 struct inode *inode = mapping->host; 934 struct gfs2_inode *ip = GFS2_I(inode); 935 unsigned long index = from >> PAGE_CACHE_SHIFT; 936 unsigned offset = from & (PAGE_CACHE_SIZE-1); 937 unsigned blocksize, iblock, length, pos; 938 struct buffer_head *bh; 939 struct page *page; 940 int err; 941 942 page = find_or_create_page(mapping, index, GFP_NOFS); 943 if (!page) 944 return 0; 945 946 blocksize = inode->i_sb->s_blocksize; 947 length = blocksize - (offset & (blocksize - 1)); 948 iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); 949 950 if (!page_has_buffers(page)) 951 create_empty_buffers(page, blocksize, 0); 952 953 /* Find the buffer that contains "offset" */ 954 bh = page_buffers(page); 955 pos = blocksize; 956 while (offset >= pos) { 957 bh = bh->b_this_page; 958 iblock++; 959 pos += blocksize; 960 } 961 962 err = 0; 963 964 if (!buffer_mapped(bh)) { 965 gfs2_block_map(inode, iblock, bh, 0); 966 /* unmapped? It's a hole - nothing to do */ 967 if (!buffer_mapped(bh)) 968 goto unlock; 969 } 970 971 /* Ok, it's mapped. Make sure it's up-to-date */ 972 if (PageUptodate(page)) 973 set_buffer_uptodate(bh); 974 975 if (!buffer_uptodate(bh)) { 976 err = -EIO; 977 ll_rw_block(READ, 1, &bh); 978 wait_on_buffer(bh); 979 /* Uhhuh. Read error. Complain and punt. */ 980 if (!buffer_uptodate(bh)) 981 goto unlock; 982 err = 0; 983 } 984 985 if (!gfs2_is_writeback(ip)) 986 gfs2_trans_add_data(ip->i_gl, bh); 987 988 zero_user(page, offset, length); 989 mark_buffer_dirty(bh); 990unlock: 991 unlock_page(page); 992 page_cache_release(page); 993 return err; 994} 995 996#define GFS2_JTRUNC_REVOKES 8192 997 998/** 999 * gfs2_journaled_truncate - Wrapper for truncate_pagecache for jdata files 1000 * @inode: The inode being truncated 1001 * @oldsize: The original (larger) size 1002 * @newsize: The new smaller size 1003 * 1004 * With jdata files, we have to journal a revoke for each block which is 1005 * truncated. As a result, we need to split this into separate transactions 1006 * if the number of pages being truncated gets too large. 1007 */ 1008 1009static int gfs2_journaled_truncate(struct inode *inode, u64 oldsize, u64 newsize) 1010{ 1011 struct gfs2_sbd *sdp = GFS2_SB(inode); 1012 u64 max_chunk = GFS2_JTRUNC_REVOKES * sdp->sd_vfs->s_blocksize; 1013 u64 chunk; 1014 int error; 1015 1016 while (oldsize != newsize) { 1017 chunk = oldsize - newsize; 1018 if (chunk > max_chunk) 1019 chunk = max_chunk; 1020 truncate_pagecache(inode, oldsize - chunk); 1021 oldsize -= chunk; 1022 gfs2_trans_end(sdp); 1023 error = gfs2_trans_begin(sdp, RES_DINODE, GFS2_JTRUNC_REVOKES); 1024 if (error) 1025 return error; 1026 } 1027 1028 return 0; 1029} 1030 1031static int trunc_start(struct inode *inode, u64 oldsize, u64 newsize) 1032{ 1033 struct gfs2_inode *ip = GFS2_I(inode); 1034 struct gfs2_sbd *sdp = GFS2_SB(inode); 1035 struct address_space *mapping = inode->i_mapping; 1036 struct buffer_head *dibh; 1037 int journaled = gfs2_is_jdata(ip); 1038 int error; 1039 1040 if (journaled) 1041 error = gfs2_trans_begin(sdp, RES_DINODE + RES_JDATA, GFS2_JTRUNC_REVOKES); 1042 else 1043 error = gfs2_trans_begin(sdp, RES_DINODE, 0); 1044 if (error) 1045 return error; 1046 1047 error = gfs2_meta_inode_buffer(ip, &dibh); 1048 if (error) 1049 goto out; 1050 1051 gfs2_trans_add_meta(ip->i_gl, dibh); 1052 1053 if (gfs2_is_stuffed(ip)) { 1054 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode) + newsize); 1055 } else { 1056 if (newsize & (u64)(sdp->sd_sb.sb_bsize - 1)) { 1057 error = gfs2_block_truncate_page(mapping, newsize); 1058 if (error) 1059 goto out_brelse; 1060 } 1061 ip->i_diskflags |= GFS2_DIF_TRUNC_IN_PROG; 1062 } 1063 1064 i_size_write(inode, newsize); 1065 ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME; 1066 gfs2_dinode_out(ip, dibh->b_data); 1067 1068 if (journaled) 1069 error = gfs2_journaled_truncate(inode, oldsize, newsize); 1070 else 1071 truncate_pagecache(inode, newsize); 1072 1073 if (error) { 1074 brelse(dibh); 1075 return error; 1076 } 1077 1078out_brelse: 1079 brelse(dibh); 1080out: 1081 gfs2_trans_end(sdp); 1082 return error; 1083} 1084 1085static int trunc_dealloc(struct gfs2_inode *ip, u64 size) 1086{ 1087 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); 1088 unsigned int height = ip->i_height; 1089 u64 lblock; 1090 struct metapath mp; 1091 int error; 1092 1093 if (!size) 1094 lblock = 0; 1095 else 1096 lblock = (size - 1) >> sdp->sd_sb.sb_bsize_shift; 1097 1098 find_metapath(sdp, lblock, &mp, ip->i_height); 1099 error = gfs2_rindex_update(sdp); 1100 if (error) 1101 return error; 1102 1103 error = gfs2_quota_hold(ip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE); 1104 if (error) 1105 return error; 1106 1107 while (height--) { 1108 struct strip_mine sm; 1109 sm.sm_first = !!size; 1110 sm.sm_height = height; 1111 1112 error = recursive_scan(ip, NULL, &mp, 0, 0, 1, &sm); 1113 if (error) 1114 break; 1115 } 1116 1117 gfs2_quota_unhold(ip); 1118 1119 return error; 1120} 1121 1122static int trunc_end(struct gfs2_inode *ip) 1123{ 1124 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); 1125 struct buffer_head *dibh; 1126 int error; 1127 1128 error = gfs2_trans_begin(sdp, RES_DINODE, 0); 1129 if (error) 1130 return error; 1131 1132 down_write(&ip->i_rw_mutex); 1133 1134 error = gfs2_meta_inode_buffer(ip, &dibh); 1135 if (error) 1136 goto out; 1137 1138 if (!i_size_read(&ip->i_inode)) { 1139 ip->i_height = 0; 1140 ip->i_goal = ip->i_no_addr; 1141 gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode)); 1142 gfs2_ordered_del_inode(ip); 1143 } 1144 ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME; 1145 ip->i_diskflags &= ~GFS2_DIF_TRUNC_IN_PROG; 1146 1147 gfs2_trans_add_meta(ip->i_gl, dibh); 1148 gfs2_dinode_out(ip, dibh->b_data); 1149 brelse(dibh); 1150 1151out: 1152 up_write(&ip->i_rw_mutex); 1153 gfs2_trans_end(sdp); 1154 return error; 1155} 1156 1157/** 1158 * do_shrink - make a file smaller 1159 * @inode: the inode 1160 * @oldsize: the current inode size 1161 * @newsize: the size to make the file 1162 * 1163 * Called with an exclusive lock on @inode. The @size must 1164 * be equal to or smaller than the current inode size. 1165 * 1166 * Returns: errno 1167 */ 1168 1169static int do_shrink(struct inode *inode, u64 oldsize, u64 newsize) 1170{ 1171 struct gfs2_inode *ip = GFS2_I(inode); 1172 int error; 1173 1174 error = trunc_start(inode, oldsize, newsize); 1175 if (error < 0) 1176 return error; 1177 if (gfs2_is_stuffed(ip)) 1178 return 0; 1179 1180 error = trunc_dealloc(ip, newsize); 1181 if (error == 0) 1182 error = trunc_end(ip); 1183 1184 return error; 1185} 1186 1187void gfs2_trim_blocks(struct inode *inode) 1188{ 1189 u64 size = inode->i_size; 1190 int ret; 1191 1192 ret = do_shrink(inode, size, size); 1193 WARN_ON(ret != 0); 1194} 1195 1196/** 1197 * do_grow - Touch and update inode size 1198 * @inode: The inode 1199 * @size: The new size 1200 * 1201 * This function updates the timestamps on the inode and 1202 * may also increase the size of the inode. This function 1203 * must not be called with @size any smaller than the current 1204 * inode size. 1205 * 1206 * Although it is not strictly required to unstuff files here, 1207 * earlier versions of GFS2 have a bug in the stuffed file reading 1208 * code which will result in a buffer overrun if the size is larger 1209 * than the max stuffed file size. In order to prevent this from 1210 * occurring, such files are unstuffed, but in other cases we can 1211 * just update the inode size directly. 1212 * 1213 * Returns: 0 on success, or -ve on error 1214 */ 1215 1216static int do_grow(struct inode *inode, u64 size) 1217{ 1218 struct gfs2_inode *ip = GFS2_I(inode); 1219 struct gfs2_sbd *sdp = GFS2_SB(inode); 1220 struct gfs2_alloc_parms ap = { .target = 1, }; 1221 struct buffer_head *dibh; 1222 int error; 1223 int unstuff = 0; 1224 1225 if (gfs2_is_stuffed(ip) && 1226 (size > (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)))) { 1227 error = gfs2_quota_lock_check(ip, &ap); 1228 if (error) 1229 return error; 1230 1231 error = gfs2_inplace_reserve(ip, &ap); 1232 if (error) 1233 goto do_grow_qunlock; 1234 unstuff = 1; 1235 } 1236 1237 error = gfs2_trans_begin(sdp, RES_DINODE + RES_STATFS + RES_RG_BIT + 1238 (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF ? 1239 0 : RES_QUOTA), 0); 1240 if (error) 1241 goto do_grow_release; 1242 1243 if (unstuff) { 1244 error = gfs2_unstuff_dinode(ip, NULL); 1245 if (error) 1246 goto do_end_trans; 1247 } 1248 1249 error = gfs2_meta_inode_buffer(ip, &dibh); 1250 if (error) 1251 goto do_end_trans; 1252 1253 i_size_write(inode, size); 1254 ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME; 1255 gfs2_trans_add_meta(ip->i_gl, dibh); 1256 gfs2_dinode_out(ip, dibh->b_data); 1257 brelse(dibh); 1258 1259do_end_trans: 1260 gfs2_trans_end(sdp); 1261do_grow_release: 1262 if (unstuff) { 1263 gfs2_inplace_release(ip); 1264do_grow_qunlock: 1265 gfs2_quota_unlock(ip); 1266 } 1267 return error; 1268} 1269 1270/** 1271 * gfs2_setattr_size - make a file a given size 1272 * @inode: the inode 1273 * @newsize: the size to make the file 1274 * 1275 * The file size can grow, shrink, or stay the same size. This 1276 * is called holding i_mutex and an exclusive glock on the inode 1277 * in question. 1278 * 1279 * Returns: errno 1280 */ 1281 1282int gfs2_setattr_size(struct inode *inode, u64 newsize) 1283{ 1284 struct gfs2_inode *ip = GFS2_I(inode); 1285 int ret; 1286 u64 oldsize; 1287 1288 BUG_ON(!S_ISREG(inode->i_mode)); 1289 1290 ret = inode_newsize_ok(inode, newsize); 1291 if (ret) 1292 return ret; 1293 1294 ret = get_write_access(inode); 1295 if (ret) 1296 return ret; 1297 1298 inode_dio_wait(inode); 1299 1300 ret = gfs2_rs_alloc(ip); 1301 if (ret) 1302 goto out; 1303 1304 oldsize = inode->i_size; 1305 if (newsize >= oldsize) { 1306 ret = do_grow(inode, newsize); 1307 goto out; 1308 } 1309 1310 gfs2_rs_deltree(ip->i_res); 1311 ret = do_shrink(inode, oldsize, newsize); 1312out: 1313 put_write_access(inode); 1314 return ret; 1315} 1316 1317int gfs2_truncatei_resume(struct gfs2_inode *ip) 1318{ 1319 int error; 1320 error = trunc_dealloc(ip, i_size_read(&ip->i_inode)); 1321 if (!error) 1322 error = trunc_end(ip); 1323 return error; 1324} 1325 1326int gfs2_file_dealloc(struct gfs2_inode *ip) 1327{ 1328 return trunc_dealloc(ip, 0); 1329} 1330 1331/** 1332 * gfs2_free_journal_extents - Free cached journal bmap info 1333 * @jd: The journal 1334 * 1335 */ 1336 1337void gfs2_free_journal_extents(struct gfs2_jdesc *jd) 1338{ 1339 struct gfs2_journal_extent *jext; 1340 1341 while(!list_empty(&jd->extent_list)) { 1342 jext = list_entry(jd->extent_list.next, struct gfs2_journal_extent, list); 1343 list_del(&jext->list); 1344 kfree(jext); 1345 } 1346} 1347 1348/** 1349 * gfs2_add_jextent - Add or merge a new extent to extent cache 1350 * @jd: The journal descriptor 1351 * @lblock: The logical block at start of new extent 1352 * @dblock: The physical block at start of new extent 1353 * @blocks: Size of extent in fs blocks 1354 * 1355 * Returns: 0 on success or -ENOMEM 1356 */ 1357 1358static int gfs2_add_jextent(struct gfs2_jdesc *jd, u64 lblock, u64 dblock, u64 blocks) 1359{ 1360 struct gfs2_journal_extent *jext; 1361 1362 if (!list_empty(&jd->extent_list)) { 1363 jext = list_entry(jd->extent_list.prev, struct gfs2_journal_extent, list); 1364 if ((jext->dblock + jext->blocks) == dblock) { 1365 jext->blocks += blocks; 1366 return 0; 1367 } 1368 } 1369 1370 jext = kzalloc(sizeof(struct gfs2_journal_extent), GFP_NOFS); 1371 if (jext == NULL) 1372 return -ENOMEM; 1373 jext->dblock = dblock; 1374 jext->lblock = lblock; 1375 jext->blocks = blocks; 1376 list_add_tail(&jext->list, &jd->extent_list); 1377 jd->nr_extents++; 1378 return 0; 1379} 1380 1381/** 1382 * gfs2_map_journal_extents - Cache journal bmap info 1383 * @sdp: The super block 1384 * @jd: The journal to map 1385 * 1386 * Create a reusable "extent" mapping from all logical 1387 * blocks to all physical blocks for the given journal. This will save 1388 * us time when writing journal blocks. Most journals will have only one 1389 * extent that maps all their logical blocks. That's because gfs2.mkfs 1390 * arranges the journal blocks sequentially to maximize performance. 1391 * So the extent would map the first block for the entire file length. 1392 * However, gfs2_jadd can happen while file activity is happening, so 1393 * those journals may not be sequential. Less likely is the case where 1394 * the users created their own journals by mounting the metafs and 1395 * laying it out. But it's still possible. These journals might have 1396 * several extents. 1397 * 1398 * Returns: 0 on success, or error on failure 1399 */ 1400 1401int gfs2_map_journal_extents(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd) 1402{ 1403 u64 lblock = 0; 1404 u64 lblock_stop; 1405 struct gfs2_inode *ip = GFS2_I(jd->jd_inode); 1406 struct buffer_head bh; 1407 unsigned int shift = sdp->sd_sb.sb_bsize_shift; 1408 u64 size; 1409 int rc; 1410 1411 lblock_stop = i_size_read(jd->jd_inode) >> shift; 1412 size = (lblock_stop - lblock) << shift; 1413 jd->nr_extents = 0; 1414 WARN_ON(!list_empty(&jd->extent_list)); 1415 1416 do { 1417 bh.b_state = 0; 1418 bh.b_blocknr = 0; 1419 bh.b_size = size; 1420 rc = gfs2_block_map(jd->jd_inode, lblock, &bh, 0); 1421 if (rc || !buffer_mapped(&bh)) 1422 goto fail; 1423 rc = gfs2_add_jextent(jd, lblock, bh.b_blocknr, bh.b_size >> shift); 1424 if (rc) 1425 goto fail; 1426 size -= bh.b_size; 1427 lblock += (bh.b_size >> ip->i_inode.i_blkbits); 1428 } while(size > 0); 1429 1430 fs_info(sdp, "journal %d mapped with %u extents\n", jd->jd_jid, 1431 jd->nr_extents); 1432 return 0; 1433 1434fail: 1435 fs_warn(sdp, "error %d mapping journal %u at offset %llu (extent %u)\n", 1436 rc, jd->jd_jid, 1437 (unsigned long long)(i_size_read(jd->jd_inode) - size), 1438 jd->nr_extents); 1439 fs_warn(sdp, "bmap=%d lblock=%llu block=%llu, state=0x%08lx, size=%llu\n", 1440 rc, (unsigned long long)lblock, (unsigned long long)bh.b_blocknr, 1441 bh.b_state, (unsigned long long)bh.b_size); 1442 gfs2_free_journal_extents(jd); 1443 return rc; 1444} 1445 1446/** 1447 * gfs2_write_alloc_required - figure out if a write will require an allocation 1448 * @ip: the file being written to 1449 * @offset: the offset to write to 1450 * @len: the number of bytes being written 1451 * 1452 * Returns: 1 if an alloc is required, 0 otherwise 1453 */ 1454 1455int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset, 1456 unsigned int len) 1457{ 1458 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); 1459 struct buffer_head bh; 1460 unsigned int shift; 1461 u64 lblock, lblock_stop, size; 1462 u64 end_of_file; 1463 1464 if (!len) 1465 return 0; 1466 1467 if (gfs2_is_stuffed(ip)) { 1468 if (offset + len > 1469 sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) 1470 return 1; 1471 return 0; 1472 } 1473 1474 shift = sdp->sd_sb.sb_bsize_shift; 1475 BUG_ON(gfs2_is_dir(ip)); 1476 end_of_file = (i_size_read(&ip->i_inode) + sdp->sd_sb.sb_bsize - 1) >> shift; 1477 lblock = offset >> shift; 1478 lblock_stop = (offset + len + sdp->sd_sb.sb_bsize - 1) >> shift; 1479 if (lblock_stop > end_of_file) 1480 return 1; 1481 1482 size = (lblock_stop - lblock) << shift; 1483 do { 1484 bh.b_state = 0; 1485 bh.b_size = size; 1486 gfs2_block_map(&ip->i_inode, lblock, &bh, 0); 1487 if (!buffer_mapped(&bh)) 1488 return 1; 1489 size -= bh.b_size; 1490 lblock += (bh.b_size >> ip->i_inode.i_blkbits); 1491 } while(size > 0); 1492 1493 return 0; 1494} 1495 1496