Alex Tomas | a86c618 | 2006-10-11 01:21:03 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com |
| 3 | * Written by Alex Tomas <alex@clusterfs.com> |
| 4 | * |
| 5 | * Architecture independence: |
| 6 | * Copyright (c) 2005, Bull S.A. |
| 7 | * Written by Pierre Peiffer <pierre.peiffer@bull.net> |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or modify |
| 10 | * it under the terms of the GNU General Public License version 2 as |
| 11 | * published by the Free Software Foundation. |
| 12 | * |
| 13 | * This program is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | * GNU General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU General Public Licens |
| 19 | * along with this program; if not, write to the Free Software |
| 20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111- |
| 21 | */ |
| 22 | |
| 23 | /* |
| 24 | * Extents support for EXT4 |
| 25 | * |
| 26 | * TODO: |
| 27 | * - ext4*_error() should be used in some situations |
| 28 | * - analyze all BUG()/BUG_ON(), use -EIO where appropriate |
| 29 | * - smart tree reduction |
| 30 | */ |
| 31 | |
| 32 | #include <linux/module.h> |
| 33 | #include <linux/fs.h> |
| 34 | #include <linux/time.h> |
| 35 | #include <linux/ext4_jbd2.h> |
| 36 | #include <linux/jbd.h> |
| 37 | #include <linux/smp_lock.h> |
| 38 | #include <linux/highuid.h> |
| 39 | #include <linux/pagemap.h> |
| 40 | #include <linux/quotaops.h> |
| 41 | #include <linux/string.h> |
| 42 | #include <linux/slab.h> |
| 43 | #include <linux/ext4_fs_extents.h> |
| 44 | #include <asm/uaccess.h> |
| 45 | |
| 46 | |
| 47 | static int ext4_ext_check_header(const char *function, struct inode *inode, |
| 48 | struct ext4_extent_header *eh) |
| 49 | { |
| 50 | const char *error_msg = NULL; |
| 51 | |
| 52 | if (unlikely(eh->eh_magic != EXT4_EXT_MAGIC)) { |
| 53 | error_msg = "invalid magic"; |
| 54 | goto corrupted; |
| 55 | } |
| 56 | if (unlikely(eh->eh_max == 0)) { |
| 57 | error_msg = "invalid eh_max"; |
| 58 | goto corrupted; |
| 59 | } |
| 60 | if (unlikely(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max))) { |
| 61 | error_msg = "invalid eh_entries"; |
| 62 | goto corrupted; |
| 63 | } |
| 64 | return 0; |
| 65 | |
| 66 | corrupted: |
| 67 | ext4_error(inode->i_sb, function, |
| 68 | "bad header in inode #%lu: %s - magic %x, " |
| 69 | "entries %u, max %u, depth %u", |
| 70 | inode->i_ino, error_msg, le16_to_cpu(eh->eh_magic), |
| 71 | le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max), |
| 72 | le16_to_cpu(eh->eh_depth)); |
| 73 | |
| 74 | return -EIO; |
| 75 | } |
| 76 | |
| 77 | static handle_t *ext4_ext_journal_restart(handle_t *handle, int needed) |
| 78 | { |
| 79 | int err; |
| 80 | |
| 81 | if (handle->h_buffer_credits > needed) |
| 82 | return handle; |
| 83 | if (!ext4_journal_extend(handle, needed)) |
| 84 | return handle; |
| 85 | err = ext4_journal_restart(handle, needed); |
| 86 | |
| 87 | return handle; |
| 88 | } |
| 89 | |
| 90 | /* |
| 91 | * could return: |
| 92 | * - EROFS |
| 93 | * - ENOMEM |
| 94 | */ |
| 95 | static int ext4_ext_get_access(handle_t *handle, struct inode *inode, |
| 96 | struct ext4_ext_path *path) |
| 97 | { |
| 98 | if (path->p_bh) { |
| 99 | /* path points to block */ |
| 100 | return ext4_journal_get_write_access(handle, path->p_bh); |
| 101 | } |
| 102 | /* path points to leaf/index in inode body */ |
| 103 | /* we use in-core data, no need to protect them */ |
| 104 | return 0; |
| 105 | } |
| 106 | |
| 107 | /* |
| 108 | * could return: |
| 109 | * - EROFS |
| 110 | * - ENOMEM |
| 111 | * - EIO |
| 112 | */ |
| 113 | static int ext4_ext_dirty(handle_t *handle, struct inode *inode, |
| 114 | struct ext4_ext_path *path) |
| 115 | { |
| 116 | int err; |
| 117 | if (path->p_bh) { |
| 118 | /* path points to block */ |
| 119 | err = ext4_journal_dirty_metadata(handle, path->p_bh); |
| 120 | } else { |
| 121 | /* path points to leaf/index in inode body */ |
| 122 | err = ext4_mark_inode_dirty(handle, inode); |
| 123 | } |
| 124 | return err; |
| 125 | } |
| 126 | |
| 127 | static int ext4_ext_find_goal(struct inode *inode, |
| 128 | struct ext4_ext_path *path, |
| 129 | unsigned long block) |
| 130 | { |
| 131 | struct ext4_inode_info *ei = EXT4_I(inode); |
| 132 | unsigned long bg_start; |
| 133 | unsigned long colour; |
| 134 | int depth; |
| 135 | |
| 136 | if (path) { |
| 137 | struct ext4_extent *ex; |
| 138 | depth = path->p_depth; |
| 139 | |
| 140 | /* try to predict block placement */ |
| 141 | if ((ex = path[depth].p_ext)) |
| 142 | return le32_to_cpu(ex->ee_start) |
| 143 | + (block - le32_to_cpu(ex->ee_block)); |
| 144 | |
| 145 | /* it looks index is empty |
| 146 | * try to find starting from index itself */ |
| 147 | if (path[depth].p_bh) |
| 148 | return path[depth].p_bh->b_blocknr; |
| 149 | } |
| 150 | |
| 151 | /* OK. use inode's group */ |
| 152 | bg_start = (ei->i_block_group * EXT4_BLOCKS_PER_GROUP(inode->i_sb)) + |
| 153 | le32_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_first_data_block); |
| 154 | colour = (current->pid % 16) * |
| 155 | (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16); |
| 156 | return bg_start + colour + block; |
| 157 | } |
| 158 | |
| 159 | static int |
| 160 | ext4_ext_new_block(handle_t *handle, struct inode *inode, |
| 161 | struct ext4_ext_path *path, |
| 162 | struct ext4_extent *ex, int *err) |
| 163 | { |
| 164 | int goal, newblock; |
| 165 | |
| 166 | goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block)); |
| 167 | newblock = ext4_new_block(handle, inode, goal, err); |
| 168 | return newblock; |
| 169 | } |
| 170 | |
| 171 | static inline int ext4_ext_space_block(struct inode *inode) |
| 172 | { |
| 173 | int size; |
| 174 | |
| 175 | size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header)) |
| 176 | / sizeof(struct ext4_extent); |
| 177 | #ifdef AGRESSIVE_TEST |
| 178 | if (size > 6) |
| 179 | size = 6; |
| 180 | #endif |
| 181 | return size; |
| 182 | } |
| 183 | |
| 184 | static inline int ext4_ext_space_block_idx(struct inode *inode) |
| 185 | { |
| 186 | int size; |
| 187 | |
| 188 | size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header)) |
| 189 | / sizeof(struct ext4_extent_idx); |
| 190 | #ifdef AGRESSIVE_TEST |
| 191 | if (size > 5) |
| 192 | size = 5; |
| 193 | #endif |
| 194 | return size; |
| 195 | } |
| 196 | |
| 197 | static inline int ext4_ext_space_root(struct inode *inode) |
| 198 | { |
| 199 | int size; |
| 200 | |
| 201 | size = sizeof(EXT4_I(inode)->i_data); |
| 202 | size -= sizeof(struct ext4_extent_header); |
| 203 | size /= sizeof(struct ext4_extent); |
| 204 | #ifdef AGRESSIVE_TEST |
| 205 | if (size > 3) |
| 206 | size = 3; |
| 207 | #endif |
| 208 | return size; |
| 209 | } |
| 210 | |
| 211 | static inline int ext4_ext_space_root_idx(struct inode *inode) |
| 212 | { |
| 213 | int size; |
| 214 | |
| 215 | size = sizeof(EXT4_I(inode)->i_data); |
| 216 | size -= sizeof(struct ext4_extent_header); |
| 217 | size /= sizeof(struct ext4_extent_idx); |
| 218 | #ifdef AGRESSIVE_TEST |
| 219 | if (size > 4) |
| 220 | size = 4; |
| 221 | #endif |
| 222 | return size; |
| 223 | } |
| 224 | |
| 225 | #ifdef EXT_DEBUG |
| 226 | static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path) |
| 227 | { |
| 228 | int k, l = path->p_depth; |
| 229 | |
| 230 | ext_debug("path:"); |
| 231 | for (k = 0; k <= l; k++, path++) { |
| 232 | if (path->p_idx) { |
| 233 | ext_debug(" %d->%d", le32_to_cpu(path->p_idx->ei_block), |
| 234 | le32_to_cpu(path->p_idx->ei_leaf)); |
| 235 | } else if (path->p_ext) { |
| 236 | ext_debug(" %d:%d:%d", |
| 237 | le32_to_cpu(path->p_ext->ee_block), |
| 238 | le16_to_cpu(path->p_ext->ee_len), |
| 239 | le32_to_cpu(path->p_ext->ee_start)); |
| 240 | } else |
| 241 | ext_debug(" []"); |
| 242 | } |
| 243 | ext_debug("\n"); |
| 244 | } |
| 245 | |
| 246 | static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path) |
| 247 | { |
| 248 | int depth = ext_depth(inode); |
| 249 | struct ext4_extent_header *eh; |
| 250 | struct ext4_extent *ex; |
| 251 | int i; |
| 252 | |
| 253 | if (!path) |
| 254 | return; |
| 255 | |
| 256 | eh = path[depth].p_hdr; |
| 257 | ex = EXT_FIRST_EXTENT(eh); |
| 258 | |
| 259 | for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) { |
| 260 | ext_debug("%d:%d:%d ", le32_to_cpu(ex->ee_block), |
| 261 | le16_to_cpu(ex->ee_len), |
| 262 | le32_to_cpu(ex->ee_start)); |
| 263 | } |
| 264 | ext_debug("\n"); |
| 265 | } |
| 266 | #else |
| 267 | #define ext4_ext_show_path(inode,path) |
| 268 | #define ext4_ext_show_leaf(inode,path) |
| 269 | #endif |
| 270 | |
| 271 | static void ext4_ext_drop_refs(struct ext4_ext_path *path) |
| 272 | { |
| 273 | int depth = path->p_depth; |
| 274 | int i; |
| 275 | |
| 276 | for (i = 0; i <= depth; i++, path++) |
| 277 | if (path->p_bh) { |
| 278 | brelse(path->p_bh); |
| 279 | path->p_bh = NULL; |
| 280 | } |
| 281 | } |
| 282 | |
| 283 | /* |
| 284 | * binary search for closest index by given block |
| 285 | */ |
| 286 | static void |
| 287 | ext4_ext_binsearch_idx(struct inode *inode, struct ext4_ext_path *path, int block) |
| 288 | { |
| 289 | struct ext4_extent_header *eh = path->p_hdr; |
| 290 | struct ext4_extent_idx *r, *l, *m; |
| 291 | |
| 292 | BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC); |
| 293 | BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max)); |
| 294 | BUG_ON(le16_to_cpu(eh->eh_entries) <= 0); |
| 295 | |
| 296 | ext_debug("binsearch for %d(idx): ", block); |
| 297 | |
| 298 | l = EXT_FIRST_INDEX(eh) + 1; |
| 299 | r = EXT_FIRST_INDEX(eh) + le16_to_cpu(eh->eh_entries) - 1; |
| 300 | while (l <= r) { |
| 301 | m = l + (r - l) / 2; |
| 302 | if (block < le32_to_cpu(m->ei_block)) |
| 303 | r = m - 1; |
| 304 | else |
| 305 | l = m + 1; |
| 306 | ext_debug("%p(%u):%p(%u):%p(%u) ", l, l->ei_block, |
| 307 | m, m->ei_block, r, r->ei_block); |
| 308 | } |
| 309 | |
| 310 | path->p_idx = l - 1; |
| 311 | ext_debug(" -> %d->%d ", le32_to_cpu(path->p_idx->ei_block), |
| 312 | le32_to_cpu(path->p_idx->ei_leaf)); |
| 313 | |
| 314 | #ifdef CHECK_BINSEARCH |
| 315 | { |
| 316 | struct ext4_extent_idx *chix, *ix; |
| 317 | int k; |
| 318 | |
| 319 | chix = ix = EXT_FIRST_INDEX(eh); |
| 320 | for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ix++) { |
| 321 | if (k != 0 && |
| 322 | le32_to_cpu(ix->ei_block) <= le32_to_cpu(ix[-1].ei_block)) { |
| 323 | printk("k=%d, ix=0x%p, first=0x%p\n", k, |
| 324 | ix, EXT_FIRST_INDEX(eh)); |
| 325 | printk("%u <= %u\n", |
| 326 | le32_to_cpu(ix->ei_block), |
| 327 | le32_to_cpu(ix[-1].ei_block)); |
| 328 | } |
| 329 | BUG_ON(k && le32_to_cpu(ix->ei_block) |
| 330 | <= le32_to_cpu(ix[-1].ei_block)); |
| 331 | if (block < le32_to_cpu(ix->ei_block)) |
| 332 | break; |
| 333 | chix = ix; |
| 334 | } |
| 335 | BUG_ON(chix != path->p_idx); |
| 336 | } |
| 337 | #endif |
| 338 | |
| 339 | } |
| 340 | |
| 341 | /* |
| 342 | * binary search for closest extent by given block |
| 343 | */ |
| 344 | static void |
| 345 | ext4_ext_binsearch(struct inode *inode, struct ext4_ext_path *path, int block) |
| 346 | { |
| 347 | struct ext4_extent_header *eh = path->p_hdr; |
| 348 | struct ext4_extent *r, *l, *m; |
| 349 | |
| 350 | BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC); |
| 351 | BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max)); |
| 352 | |
| 353 | if (eh->eh_entries == 0) { |
| 354 | /* |
| 355 | * this leaf is empty yet: |
| 356 | * we get such a leaf in split/add case |
| 357 | */ |
| 358 | return; |
| 359 | } |
| 360 | |
| 361 | ext_debug("binsearch for %d: ", block); |
| 362 | |
| 363 | l = EXT_FIRST_EXTENT(eh) + 1; |
| 364 | r = EXT_FIRST_EXTENT(eh) + le16_to_cpu(eh->eh_entries) - 1; |
| 365 | |
| 366 | while (l <= r) { |
| 367 | m = l + (r - l) / 2; |
| 368 | if (block < le32_to_cpu(m->ee_block)) |
| 369 | r = m - 1; |
| 370 | else |
| 371 | l = m + 1; |
| 372 | ext_debug("%p(%u):%p(%u):%p(%u) ", l, l->ee_block, |
| 373 | m, m->ee_block, r, r->ee_block); |
| 374 | } |
| 375 | |
| 376 | path->p_ext = l - 1; |
| 377 | ext_debug(" -> %d:%d:%d ", |
| 378 | le32_to_cpu(path->p_ext->ee_block), |
| 379 | le32_to_cpu(path->p_ext->ee_start), |
| 380 | le16_to_cpu(path->p_ext->ee_len)); |
| 381 | |
| 382 | #ifdef CHECK_BINSEARCH |
| 383 | { |
| 384 | struct ext4_extent *chex, *ex; |
| 385 | int k; |
| 386 | |
| 387 | chex = ex = EXT_FIRST_EXTENT(eh); |
| 388 | for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ex++) { |
| 389 | BUG_ON(k && le32_to_cpu(ex->ee_block) |
| 390 | <= le32_to_cpu(ex[-1].ee_block)); |
| 391 | if (block < le32_to_cpu(ex->ee_block)) |
| 392 | break; |
| 393 | chex = ex; |
| 394 | } |
| 395 | BUG_ON(chex != path->p_ext); |
| 396 | } |
| 397 | #endif |
| 398 | |
| 399 | } |
| 400 | |
| 401 | int ext4_ext_tree_init(handle_t *handle, struct inode *inode) |
| 402 | { |
| 403 | struct ext4_extent_header *eh; |
| 404 | |
| 405 | eh = ext_inode_hdr(inode); |
| 406 | eh->eh_depth = 0; |
| 407 | eh->eh_entries = 0; |
| 408 | eh->eh_magic = EXT4_EXT_MAGIC; |
| 409 | eh->eh_max = cpu_to_le16(ext4_ext_space_root(inode)); |
| 410 | ext4_mark_inode_dirty(handle, inode); |
| 411 | ext4_ext_invalidate_cache(inode); |
| 412 | return 0; |
| 413 | } |
| 414 | |
| 415 | struct ext4_ext_path * |
| 416 | ext4_ext_find_extent(struct inode *inode, int block, struct ext4_ext_path *path) |
| 417 | { |
| 418 | struct ext4_extent_header *eh; |
| 419 | struct buffer_head *bh; |
| 420 | short int depth, i, ppos = 0, alloc = 0; |
| 421 | |
| 422 | eh = ext_inode_hdr(inode); |
| 423 | BUG_ON(eh == NULL); |
| 424 | if (ext4_ext_check_header(__FUNCTION__, inode, eh)) |
| 425 | return ERR_PTR(-EIO); |
| 426 | |
| 427 | i = depth = ext_depth(inode); |
| 428 | |
| 429 | /* account possible depth increase */ |
| 430 | if (!path) { |
| 431 | path = kmalloc(sizeof(struct ext4_ext_path) * (depth + 2), |
| 432 | GFP_NOFS); |
| 433 | if (!path) |
| 434 | return ERR_PTR(-ENOMEM); |
| 435 | alloc = 1; |
| 436 | } |
| 437 | memset(path, 0, sizeof(struct ext4_ext_path) * (depth + 1)); |
| 438 | path[0].p_hdr = eh; |
| 439 | |
| 440 | /* walk through the tree */ |
| 441 | while (i) { |
| 442 | ext_debug("depth %d: num %d, max %d\n", |
| 443 | ppos, le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max)); |
| 444 | ext4_ext_binsearch_idx(inode, path + ppos, block); |
| 445 | path[ppos].p_block = le32_to_cpu(path[ppos].p_idx->ei_leaf); |
| 446 | path[ppos].p_depth = i; |
| 447 | path[ppos].p_ext = NULL; |
| 448 | |
| 449 | bh = sb_bread(inode->i_sb, path[ppos].p_block); |
| 450 | if (!bh) |
| 451 | goto err; |
| 452 | |
| 453 | eh = ext_block_hdr(bh); |
| 454 | ppos++; |
| 455 | BUG_ON(ppos > depth); |
| 456 | path[ppos].p_bh = bh; |
| 457 | path[ppos].p_hdr = eh; |
| 458 | i--; |
| 459 | |
| 460 | if (ext4_ext_check_header(__FUNCTION__, inode, eh)) |
| 461 | goto err; |
| 462 | } |
| 463 | |
| 464 | path[ppos].p_depth = i; |
| 465 | path[ppos].p_hdr = eh; |
| 466 | path[ppos].p_ext = NULL; |
| 467 | path[ppos].p_idx = NULL; |
| 468 | |
| 469 | if (ext4_ext_check_header(__FUNCTION__, inode, eh)) |
| 470 | goto err; |
| 471 | |
| 472 | /* find extent */ |
| 473 | ext4_ext_binsearch(inode, path + ppos, block); |
| 474 | |
| 475 | ext4_ext_show_path(inode, path); |
| 476 | |
| 477 | return path; |
| 478 | |
| 479 | err: |
| 480 | ext4_ext_drop_refs(path); |
| 481 | if (alloc) |
| 482 | kfree(path); |
| 483 | return ERR_PTR(-EIO); |
| 484 | } |
| 485 | |
| 486 | /* |
| 487 | * insert new index [logical;ptr] into the block at cupr |
| 488 | * it check where to insert: before curp or after curp |
| 489 | */ |
| 490 | static int ext4_ext_insert_index(handle_t *handle, struct inode *inode, |
| 491 | struct ext4_ext_path *curp, |
| 492 | int logical, int ptr) |
| 493 | { |
| 494 | struct ext4_extent_idx *ix; |
| 495 | int len, err; |
| 496 | |
| 497 | if ((err = ext4_ext_get_access(handle, inode, curp))) |
| 498 | return err; |
| 499 | |
| 500 | BUG_ON(logical == le32_to_cpu(curp->p_idx->ei_block)); |
| 501 | len = EXT_MAX_INDEX(curp->p_hdr) - curp->p_idx; |
| 502 | if (logical > le32_to_cpu(curp->p_idx->ei_block)) { |
| 503 | /* insert after */ |
| 504 | if (curp->p_idx != EXT_LAST_INDEX(curp->p_hdr)) { |
| 505 | len = (len - 1) * sizeof(struct ext4_extent_idx); |
| 506 | len = len < 0 ? 0 : len; |
| 507 | ext_debug("insert new index %d after: %d. " |
| 508 | "move %d from 0x%p to 0x%p\n", |
| 509 | logical, ptr, len, |
| 510 | (curp->p_idx + 1), (curp->p_idx + 2)); |
| 511 | memmove(curp->p_idx + 2, curp->p_idx + 1, len); |
| 512 | } |
| 513 | ix = curp->p_idx + 1; |
| 514 | } else { |
| 515 | /* insert before */ |
| 516 | len = len * sizeof(struct ext4_extent_idx); |
| 517 | len = len < 0 ? 0 : len; |
| 518 | ext_debug("insert new index %d before: %d. " |
| 519 | "move %d from 0x%p to 0x%p\n", |
| 520 | logical, ptr, len, |
| 521 | curp->p_idx, (curp->p_idx + 1)); |
| 522 | memmove(curp->p_idx + 1, curp->p_idx, len); |
| 523 | ix = curp->p_idx; |
| 524 | } |
| 525 | |
| 526 | ix->ei_block = cpu_to_le32(logical); |
| 527 | ix->ei_leaf = cpu_to_le32(ptr); |
| 528 | curp->p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(curp->p_hdr->eh_entries)+1); |
| 529 | |
| 530 | BUG_ON(le16_to_cpu(curp->p_hdr->eh_entries) |
| 531 | > le16_to_cpu(curp->p_hdr->eh_max)); |
| 532 | BUG_ON(ix > EXT_LAST_INDEX(curp->p_hdr)); |
| 533 | |
| 534 | err = ext4_ext_dirty(handle, inode, curp); |
| 535 | ext4_std_error(inode->i_sb, err); |
| 536 | |
| 537 | return err; |
| 538 | } |
| 539 | |
| 540 | /* |
| 541 | * routine inserts new subtree into the path, using free index entry |
| 542 | * at depth 'at: |
| 543 | * - allocates all needed blocks (new leaf and all intermediate index blocks) |
| 544 | * - makes decision where to split |
| 545 | * - moves remaining extens and index entries (right to the split point) |
| 546 | * into the newly allocated blocks |
| 547 | * - initialize subtree |
| 548 | */ |
| 549 | static int ext4_ext_split(handle_t *handle, struct inode *inode, |
| 550 | struct ext4_ext_path *path, |
| 551 | struct ext4_extent *newext, int at) |
| 552 | { |
| 553 | struct buffer_head *bh = NULL; |
| 554 | int depth = ext_depth(inode); |
| 555 | struct ext4_extent_header *neh; |
| 556 | struct ext4_extent_idx *fidx; |
| 557 | struct ext4_extent *ex; |
| 558 | int i = at, k, m, a; |
| 559 | unsigned long newblock, oldblock; |
| 560 | __le32 border; |
| 561 | int *ablocks = NULL; /* array of allocated blocks */ |
| 562 | int err = 0; |
| 563 | |
| 564 | /* make decision: where to split? */ |
| 565 | /* FIXME: now desicion is simplest: at current extent */ |
| 566 | |
| 567 | /* if current leaf will be splitted, then we should use |
| 568 | * border from split point */ |
| 569 | BUG_ON(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr)); |
| 570 | if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) { |
| 571 | border = path[depth].p_ext[1].ee_block; |
| 572 | ext_debug("leaf will be splitted." |
| 573 | " next leaf starts at %d\n", |
| 574 | le32_to_cpu(border)); |
| 575 | } else { |
| 576 | border = newext->ee_block; |
| 577 | ext_debug("leaf will be added." |
| 578 | " next leaf starts at %d\n", |
| 579 | le32_to_cpu(border)); |
| 580 | } |
| 581 | |
| 582 | /* |
| 583 | * if error occurs, then we break processing |
| 584 | * and turn filesystem read-only. so, index won't |
| 585 | * be inserted and tree will be in consistent |
| 586 | * state. next mount will repair buffers too |
| 587 | */ |
| 588 | |
| 589 | /* |
| 590 | * get array to track all allocated blocks |
| 591 | * we need this to handle errors and free blocks |
| 592 | * upon them |
| 593 | */ |
| 594 | ablocks = kmalloc(sizeof(unsigned long) * depth, GFP_NOFS); |
| 595 | if (!ablocks) |
| 596 | return -ENOMEM; |
| 597 | memset(ablocks, 0, sizeof(unsigned long) * depth); |
| 598 | |
| 599 | /* allocate all needed blocks */ |
| 600 | ext_debug("allocate %d blocks for indexes/leaf\n", depth - at); |
| 601 | for (a = 0; a < depth - at; a++) { |
| 602 | newblock = ext4_ext_new_block(handle, inode, path, newext, &err); |
| 603 | if (newblock == 0) |
| 604 | goto cleanup; |
| 605 | ablocks[a] = newblock; |
| 606 | } |
| 607 | |
| 608 | /* initialize new leaf */ |
| 609 | newblock = ablocks[--a]; |
| 610 | BUG_ON(newblock == 0); |
| 611 | bh = sb_getblk(inode->i_sb, newblock); |
| 612 | if (!bh) { |
| 613 | err = -EIO; |
| 614 | goto cleanup; |
| 615 | } |
| 616 | lock_buffer(bh); |
| 617 | |
| 618 | if ((err = ext4_journal_get_create_access(handle, bh))) |
| 619 | goto cleanup; |
| 620 | |
| 621 | neh = ext_block_hdr(bh); |
| 622 | neh->eh_entries = 0; |
| 623 | neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode)); |
| 624 | neh->eh_magic = EXT4_EXT_MAGIC; |
| 625 | neh->eh_depth = 0; |
| 626 | ex = EXT_FIRST_EXTENT(neh); |
| 627 | |
| 628 | /* move remain of path[depth] to the new leaf */ |
| 629 | BUG_ON(path[depth].p_hdr->eh_entries != path[depth].p_hdr->eh_max); |
| 630 | /* start copy from next extent */ |
| 631 | /* TODO: we could do it by single memmove */ |
| 632 | m = 0; |
| 633 | path[depth].p_ext++; |
| 634 | while (path[depth].p_ext <= |
| 635 | EXT_MAX_EXTENT(path[depth].p_hdr)) { |
| 636 | ext_debug("move %d:%d:%d in new leaf %lu\n", |
| 637 | le32_to_cpu(path[depth].p_ext->ee_block), |
| 638 | le32_to_cpu(path[depth].p_ext->ee_start), |
| 639 | le16_to_cpu(path[depth].p_ext->ee_len), |
| 640 | newblock); |
| 641 | /*memmove(ex++, path[depth].p_ext++, |
| 642 | sizeof(struct ext4_extent)); |
| 643 | neh->eh_entries++;*/ |
| 644 | path[depth].p_ext++; |
| 645 | m++; |
| 646 | } |
| 647 | if (m) { |
| 648 | memmove(ex, path[depth].p_ext-m, sizeof(struct ext4_extent)*m); |
| 649 | neh->eh_entries = cpu_to_le16(le16_to_cpu(neh->eh_entries)+m); |
| 650 | } |
| 651 | |
| 652 | set_buffer_uptodate(bh); |
| 653 | unlock_buffer(bh); |
| 654 | |
| 655 | if ((err = ext4_journal_dirty_metadata(handle, bh))) |
| 656 | goto cleanup; |
| 657 | brelse(bh); |
| 658 | bh = NULL; |
| 659 | |
| 660 | /* correct old leaf */ |
| 661 | if (m) { |
| 662 | if ((err = ext4_ext_get_access(handle, inode, path + depth))) |
| 663 | goto cleanup; |
| 664 | path[depth].p_hdr->eh_entries = |
| 665 | cpu_to_le16(le16_to_cpu(path[depth].p_hdr->eh_entries)-m); |
| 666 | if ((err = ext4_ext_dirty(handle, inode, path + depth))) |
| 667 | goto cleanup; |
| 668 | |
| 669 | } |
| 670 | |
| 671 | /* create intermediate indexes */ |
| 672 | k = depth - at - 1; |
| 673 | BUG_ON(k < 0); |
| 674 | if (k) |
| 675 | ext_debug("create %d intermediate indices\n", k); |
| 676 | /* insert new index into current index block */ |
| 677 | /* current depth stored in i var */ |
| 678 | i = depth - 1; |
| 679 | while (k--) { |
| 680 | oldblock = newblock; |
| 681 | newblock = ablocks[--a]; |
| 682 | bh = sb_getblk(inode->i_sb, newblock); |
| 683 | if (!bh) { |
| 684 | err = -EIO; |
| 685 | goto cleanup; |
| 686 | } |
| 687 | lock_buffer(bh); |
| 688 | |
| 689 | if ((err = ext4_journal_get_create_access(handle, bh))) |
| 690 | goto cleanup; |
| 691 | |
| 692 | neh = ext_block_hdr(bh); |
| 693 | neh->eh_entries = cpu_to_le16(1); |
| 694 | neh->eh_magic = EXT4_EXT_MAGIC; |
| 695 | neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode)); |
| 696 | neh->eh_depth = cpu_to_le16(depth - i); |
| 697 | fidx = EXT_FIRST_INDEX(neh); |
| 698 | fidx->ei_block = border; |
| 699 | fidx->ei_leaf = cpu_to_le32(oldblock); |
| 700 | |
| 701 | ext_debug("int.index at %d (block %lu): %lu -> %lu\n", i, |
| 702 | newblock, (unsigned long) le32_to_cpu(border), |
| 703 | oldblock); |
| 704 | /* copy indexes */ |
| 705 | m = 0; |
| 706 | path[i].p_idx++; |
| 707 | |
| 708 | ext_debug("cur 0x%p, last 0x%p\n", path[i].p_idx, |
| 709 | EXT_MAX_INDEX(path[i].p_hdr)); |
| 710 | BUG_ON(EXT_MAX_INDEX(path[i].p_hdr) != |
| 711 | EXT_LAST_INDEX(path[i].p_hdr)); |
| 712 | while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) { |
| 713 | ext_debug("%d: move %d:%d in new index %lu\n", i, |
| 714 | le32_to_cpu(path[i].p_idx->ei_block), |
| 715 | le32_to_cpu(path[i].p_idx->ei_leaf), |
| 716 | newblock); |
| 717 | /*memmove(++fidx, path[i].p_idx++, |
| 718 | sizeof(struct ext4_extent_idx)); |
| 719 | neh->eh_entries++; |
| 720 | BUG_ON(neh->eh_entries > neh->eh_max);*/ |
| 721 | path[i].p_idx++; |
| 722 | m++; |
| 723 | } |
| 724 | if (m) { |
| 725 | memmove(++fidx, path[i].p_idx - m, |
| 726 | sizeof(struct ext4_extent_idx) * m); |
| 727 | neh->eh_entries = |
| 728 | cpu_to_le16(le16_to_cpu(neh->eh_entries) + m); |
| 729 | } |
| 730 | set_buffer_uptodate(bh); |
| 731 | unlock_buffer(bh); |
| 732 | |
| 733 | if ((err = ext4_journal_dirty_metadata(handle, bh))) |
| 734 | goto cleanup; |
| 735 | brelse(bh); |
| 736 | bh = NULL; |
| 737 | |
| 738 | /* correct old index */ |
| 739 | if (m) { |
| 740 | err = ext4_ext_get_access(handle, inode, path + i); |
| 741 | if (err) |
| 742 | goto cleanup; |
| 743 | path[i].p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(path[i].p_hdr->eh_entries)-m); |
| 744 | err = ext4_ext_dirty(handle, inode, path + i); |
| 745 | if (err) |
| 746 | goto cleanup; |
| 747 | } |
| 748 | |
| 749 | i--; |
| 750 | } |
| 751 | |
| 752 | /* insert new index */ |
| 753 | if (err) |
| 754 | goto cleanup; |
| 755 | |
| 756 | err = ext4_ext_insert_index(handle, inode, path + at, |
| 757 | le32_to_cpu(border), newblock); |
| 758 | |
| 759 | cleanup: |
| 760 | if (bh) { |
| 761 | if (buffer_locked(bh)) |
| 762 | unlock_buffer(bh); |
| 763 | brelse(bh); |
| 764 | } |
| 765 | |
| 766 | if (err) { |
| 767 | /* free all allocated blocks in error case */ |
| 768 | for (i = 0; i < depth; i++) { |
| 769 | if (!ablocks[i]) |
| 770 | continue; |
| 771 | ext4_free_blocks(handle, inode, ablocks[i], 1); |
| 772 | } |
| 773 | } |
| 774 | kfree(ablocks); |
| 775 | |
| 776 | return err; |
| 777 | } |
| 778 | |
| 779 | /* |
| 780 | * routine implements tree growing procedure: |
| 781 | * - allocates new block |
| 782 | * - moves top-level data (index block or leaf) into the new block |
| 783 | * - initialize new top-level, creating index that points to the |
| 784 | * just created block |
| 785 | */ |
| 786 | static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode, |
| 787 | struct ext4_ext_path *path, |
| 788 | struct ext4_extent *newext) |
| 789 | { |
| 790 | struct ext4_ext_path *curp = path; |
| 791 | struct ext4_extent_header *neh; |
| 792 | struct ext4_extent_idx *fidx; |
| 793 | struct buffer_head *bh; |
| 794 | unsigned long newblock; |
| 795 | int err = 0; |
| 796 | |
| 797 | newblock = ext4_ext_new_block(handle, inode, path, newext, &err); |
| 798 | if (newblock == 0) |
| 799 | return err; |
| 800 | |
| 801 | bh = sb_getblk(inode->i_sb, newblock); |
| 802 | if (!bh) { |
| 803 | err = -EIO; |
| 804 | ext4_std_error(inode->i_sb, err); |
| 805 | return err; |
| 806 | } |
| 807 | lock_buffer(bh); |
| 808 | |
| 809 | if ((err = ext4_journal_get_create_access(handle, bh))) { |
| 810 | unlock_buffer(bh); |
| 811 | goto out; |
| 812 | } |
| 813 | |
| 814 | /* move top-level index/leaf into new block */ |
| 815 | memmove(bh->b_data, curp->p_hdr, sizeof(EXT4_I(inode)->i_data)); |
| 816 | |
| 817 | /* set size of new block */ |
| 818 | neh = ext_block_hdr(bh); |
| 819 | /* old root could have indexes or leaves |
| 820 | * so calculate e_max right way */ |
| 821 | if (ext_depth(inode)) |
| 822 | neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode)); |
| 823 | else |
| 824 | neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode)); |
| 825 | neh->eh_magic = EXT4_EXT_MAGIC; |
| 826 | set_buffer_uptodate(bh); |
| 827 | unlock_buffer(bh); |
| 828 | |
| 829 | if ((err = ext4_journal_dirty_metadata(handle, bh))) |
| 830 | goto out; |
| 831 | |
| 832 | /* create index in new top-level index: num,max,pointer */ |
| 833 | if ((err = ext4_ext_get_access(handle, inode, curp))) |
| 834 | goto out; |
| 835 | |
| 836 | curp->p_hdr->eh_magic = EXT4_EXT_MAGIC; |
| 837 | curp->p_hdr->eh_max = cpu_to_le16(ext4_ext_space_root_idx(inode)); |
| 838 | curp->p_hdr->eh_entries = cpu_to_le16(1); |
| 839 | curp->p_idx = EXT_FIRST_INDEX(curp->p_hdr); |
| 840 | /* FIXME: it works, but actually path[0] can be index */ |
| 841 | curp->p_idx->ei_block = EXT_FIRST_EXTENT(path[0].p_hdr)->ee_block; |
| 842 | curp->p_idx->ei_leaf = cpu_to_le32(newblock); |
| 843 | |
| 844 | neh = ext_inode_hdr(inode); |
| 845 | fidx = EXT_FIRST_INDEX(neh); |
| 846 | ext_debug("new root: num %d(%d), lblock %d, ptr %d\n", |
| 847 | le16_to_cpu(neh->eh_entries), le16_to_cpu(neh->eh_max), |
| 848 | le32_to_cpu(fidx->ei_block), le32_to_cpu(fidx->ei_leaf)); |
| 849 | |
| 850 | neh->eh_depth = cpu_to_le16(path->p_depth + 1); |
| 851 | err = ext4_ext_dirty(handle, inode, curp); |
| 852 | out: |
| 853 | brelse(bh); |
| 854 | |
| 855 | return err; |
| 856 | } |
| 857 | |
| 858 | /* |
| 859 | * routine finds empty index and adds new leaf. if no free index found |
| 860 | * then it requests in-depth growing |
| 861 | */ |
| 862 | static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode, |
| 863 | struct ext4_ext_path *path, |
| 864 | struct ext4_extent *newext) |
| 865 | { |
| 866 | struct ext4_ext_path *curp; |
| 867 | int depth, i, err = 0; |
| 868 | |
| 869 | repeat: |
| 870 | i = depth = ext_depth(inode); |
| 871 | |
| 872 | /* walk up to the tree and look for free index entry */ |
| 873 | curp = path + depth; |
| 874 | while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) { |
| 875 | i--; |
| 876 | curp--; |
| 877 | } |
| 878 | |
| 879 | /* we use already allocated block for index block |
| 880 | * so, subsequent data blocks should be contigoues */ |
| 881 | if (EXT_HAS_FREE_INDEX(curp)) { |
| 882 | /* if we found index with free entry, then use that |
| 883 | * entry: create all needed subtree and add new leaf */ |
| 884 | err = ext4_ext_split(handle, inode, path, newext, i); |
| 885 | |
| 886 | /* refill path */ |
| 887 | ext4_ext_drop_refs(path); |
| 888 | path = ext4_ext_find_extent(inode, |
| 889 | le32_to_cpu(newext->ee_block), |
| 890 | path); |
| 891 | if (IS_ERR(path)) |
| 892 | err = PTR_ERR(path); |
| 893 | } else { |
| 894 | /* tree is full, time to grow in depth */ |
| 895 | err = ext4_ext_grow_indepth(handle, inode, path, newext); |
| 896 | if (err) |
| 897 | goto out; |
| 898 | |
| 899 | /* refill path */ |
| 900 | ext4_ext_drop_refs(path); |
| 901 | path = ext4_ext_find_extent(inode, |
| 902 | le32_to_cpu(newext->ee_block), |
| 903 | path); |
| 904 | if (IS_ERR(path)) { |
| 905 | err = PTR_ERR(path); |
| 906 | goto out; |
| 907 | } |
| 908 | |
| 909 | /* |
| 910 | * only first (depth 0 -> 1) produces free space |
| 911 | * in all other cases we have to split growed tree |
| 912 | */ |
| 913 | depth = ext_depth(inode); |
| 914 | if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) { |
| 915 | /* now we need split */ |
| 916 | goto repeat; |
| 917 | } |
| 918 | } |
| 919 | |
| 920 | out: |
| 921 | return err; |
| 922 | } |
| 923 | |
| 924 | /* |
| 925 | * returns allocated block in subsequent extent or EXT_MAX_BLOCK |
| 926 | * NOTE: it consider block number from index entry as |
| 927 | * allocated block. thus, index entries have to be consistent |
| 928 | * with leafs |
| 929 | */ |
| 930 | static unsigned long |
| 931 | ext4_ext_next_allocated_block(struct ext4_ext_path *path) |
| 932 | { |
| 933 | int depth; |
| 934 | |
| 935 | BUG_ON(path == NULL); |
| 936 | depth = path->p_depth; |
| 937 | |
| 938 | if (depth == 0 && path->p_ext == NULL) |
| 939 | return EXT_MAX_BLOCK; |
| 940 | |
| 941 | while (depth >= 0) { |
| 942 | if (depth == path->p_depth) { |
| 943 | /* leaf */ |
| 944 | if (path[depth].p_ext != |
| 945 | EXT_LAST_EXTENT(path[depth].p_hdr)) |
| 946 | return le32_to_cpu(path[depth].p_ext[1].ee_block); |
| 947 | } else { |
| 948 | /* index */ |
| 949 | if (path[depth].p_idx != |
| 950 | EXT_LAST_INDEX(path[depth].p_hdr)) |
| 951 | return le32_to_cpu(path[depth].p_idx[1].ei_block); |
| 952 | } |
| 953 | depth--; |
| 954 | } |
| 955 | |
| 956 | return EXT_MAX_BLOCK; |
| 957 | } |
| 958 | |
| 959 | /* |
| 960 | * returns first allocated block from next leaf or EXT_MAX_BLOCK |
| 961 | */ |
| 962 | static unsigned ext4_ext_next_leaf_block(struct inode *inode, |
| 963 | struct ext4_ext_path *path) |
| 964 | { |
| 965 | int depth; |
| 966 | |
| 967 | BUG_ON(path == NULL); |
| 968 | depth = path->p_depth; |
| 969 | |
| 970 | /* zero-tree has no leaf blocks at all */ |
| 971 | if (depth == 0) |
| 972 | return EXT_MAX_BLOCK; |
| 973 | |
| 974 | /* go to index block */ |
| 975 | depth--; |
| 976 | |
| 977 | while (depth >= 0) { |
| 978 | if (path[depth].p_idx != |
| 979 | EXT_LAST_INDEX(path[depth].p_hdr)) |
| 980 | return le32_to_cpu(path[depth].p_idx[1].ei_block); |
| 981 | depth--; |
| 982 | } |
| 983 | |
| 984 | return EXT_MAX_BLOCK; |
| 985 | } |
| 986 | |
| 987 | /* |
| 988 | * if leaf gets modified and modified extent is first in the leaf |
| 989 | * then we have to correct all indexes above |
| 990 | * TODO: do we need to correct tree in all cases? |
| 991 | */ |
| 992 | int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode, |
| 993 | struct ext4_ext_path *path) |
| 994 | { |
| 995 | struct ext4_extent_header *eh; |
| 996 | int depth = ext_depth(inode); |
| 997 | struct ext4_extent *ex; |
| 998 | __le32 border; |
| 999 | int k, err = 0; |
| 1000 | |
| 1001 | eh = path[depth].p_hdr; |
| 1002 | ex = path[depth].p_ext; |
| 1003 | BUG_ON(ex == NULL); |
| 1004 | BUG_ON(eh == NULL); |
| 1005 | |
| 1006 | if (depth == 0) { |
| 1007 | /* there is no tree at all */ |
| 1008 | return 0; |
| 1009 | } |
| 1010 | |
| 1011 | if (ex != EXT_FIRST_EXTENT(eh)) { |
| 1012 | /* we correct tree if first leaf got modified only */ |
| 1013 | return 0; |
| 1014 | } |
| 1015 | |
| 1016 | /* |
| 1017 | * TODO: we need correction if border is smaller then current one |
| 1018 | */ |
| 1019 | k = depth - 1; |
| 1020 | border = path[depth].p_ext->ee_block; |
| 1021 | if ((err = ext4_ext_get_access(handle, inode, path + k))) |
| 1022 | return err; |
| 1023 | path[k].p_idx->ei_block = border; |
| 1024 | if ((err = ext4_ext_dirty(handle, inode, path + k))) |
| 1025 | return err; |
| 1026 | |
| 1027 | while (k--) { |
| 1028 | /* change all left-side indexes */ |
| 1029 | if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr)) |
| 1030 | break; |
| 1031 | if ((err = ext4_ext_get_access(handle, inode, path + k))) |
| 1032 | break; |
| 1033 | path[k].p_idx->ei_block = border; |
| 1034 | if ((err = ext4_ext_dirty(handle, inode, path + k))) |
| 1035 | break; |
| 1036 | } |
| 1037 | |
| 1038 | return err; |
| 1039 | } |
| 1040 | |
| 1041 | static int inline |
| 1042 | ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1, |
| 1043 | struct ext4_extent *ex2) |
| 1044 | { |
| 1045 | /* FIXME: 48bit support */ |
| 1046 | if (le32_to_cpu(ex1->ee_block) + le16_to_cpu(ex1->ee_len) |
| 1047 | != le32_to_cpu(ex2->ee_block)) |
| 1048 | return 0; |
| 1049 | |
| 1050 | #ifdef AGRESSIVE_TEST |
| 1051 | if (le16_to_cpu(ex1->ee_len) >= 4) |
| 1052 | return 0; |
| 1053 | #endif |
| 1054 | |
| 1055 | if (le32_to_cpu(ex1->ee_start) + le16_to_cpu(ex1->ee_len) |
| 1056 | == le32_to_cpu(ex2->ee_start)) |
| 1057 | return 1; |
| 1058 | return 0; |
| 1059 | } |
| 1060 | |
| 1061 | /* |
| 1062 | * this routine tries to merge requsted extent into the existing |
| 1063 | * extent or inserts requested extent as new one into the tree, |
| 1064 | * creating new leaf in no-space case |
| 1065 | */ |
| 1066 | int ext4_ext_insert_extent(handle_t *handle, struct inode *inode, |
| 1067 | struct ext4_ext_path *path, |
| 1068 | struct ext4_extent *newext) |
| 1069 | { |
| 1070 | struct ext4_extent_header * eh; |
| 1071 | struct ext4_extent *ex, *fex; |
| 1072 | struct ext4_extent *nearex; /* nearest extent */ |
| 1073 | struct ext4_ext_path *npath = NULL; |
| 1074 | int depth, len, err, next; |
| 1075 | |
| 1076 | BUG_ON(newext->ee_len == 0); |
| 1077 | depth = ext_depth(inode); |
| 1078 | ex = path[depth].p_ext; |
| 1079 | BUG_ON(path[depth].p_hdr == NULL); |
| 1080 | |
| 1081 | /* try to insert block into found extent and return */ |
| 1082 | if (ex && ext4_can_extents_be_merged(inode, ex, newext)) { |
| 1083 | ext_debug("append %d block to %d:%d (from %d)\n", |
| 1084 | le16_to_cpu(newext->ee_len), |
| 1085 | le32_to_cpu(ex->ee_block), |
| 1086 | le16_to_cpu(ex->ee_len), |
| 1087 | le32_to_cpu(ex->ee_start)); |
| 1088 | if ((err = ext4_ext_get_access(handle, inode, path + depth))) |
| 1089 | return err; |
| 1090 | ex->ee_len = cpu_to_le16(le16_to_cpu(ex->ee_len) |
| 1091 | + le16_to_cpu(newext->ee_len)); |
| 1092 | eh = path[depth].p_hdr; |
| 1093 | nearex = ex; |
| 1094 | goto merge; |
| 1095 | } |
| 1096 | |
| 1097 | repeat: |
| 1098 | depth = ext_depth(inode); |
| 1099 | eh = path[depth].p_hdr; |
| 1100 | if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) |
| 1101 | goto has_space; |
| 1102 | |
| 1103 | /* probably next leaf has space for us? */ |
| 1104 | fex = EXT_LAST_EXTENT(eh); |
| 1105 | next = ext4_ext_next_leaf_block(inode, path); |
| 1106 | if (le32_to_cpu(newext->ee_block) > le32_to_cpu(fex->ee_block) |
| 1107 | && next != EXT_MAX_BLOCK) { |
| 1108 | ext_debug("next leaf block - %d\n", next); |
| 1109 | BUG_ON(npath != NULL); |
| 1110 | npath = ext4_ext_find_extent(inode, next, NULL); |
| 1111 | if (IS_ERR(npath)) |
| 1112 | return PTR_ERR(npath); |
| 1113 | BUG_ON(npath->p_depth != path->p_depth); |
| 1114 | eh = npath[depth].p_hdr; |
| 1115 | if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) { |
| 1116 | ext_debug("next leaf isnt full(%d)\n", |
| 1117 | le16_to_cpu(eh->eh_entries)); |
| 1118 | path = npath; |
| 1119 | goto repeat; |
| 1120 | } |
| 1121 | ext_debug("next leaf has no free space(%d,%d)\n", |
| 1122 | le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max)); |
| 1123 | } |
| 1124 | |
| 1125 | /* |
| 1126 | * there is no free space in found leaf |
| 1127 | * we're gonna add new leaf in the tree |
| 1128 | */ |
| 1129 | err = ext4_ext_create_new_leaf(handle, inode, path, newext); |
| 1130 | if (err) |
| 1131 | goto cleanup; |
| 1132 | depth = ext_depth(inode); |
| 1133 | eh = path[depth].p_hdr; |
| 1134 | |
| 1135 | has_space: |
| 1136 | nearex = path[depth].p_ext; |
| 1137 | |
| 1138 | if ((err = ext4_ext_get_access(handle, inode, path + depth))) |
| 1139 | goto cleanup; |
| 1140 | |
| 1141 | if (!nearex) { |
| 1142 | /* there is no extent in this leaf, create first one */ |
| 1143 | ext_debug("first extent in the leaf: %d:%d:%d\n", |
| 1144 | le32_to_cpu(newext->ee_block), |
| 1145 | le32_to_cpu(newext->ee_start), |
| 1146 | le16_to_cpu(newext->ee_len)); |
| 1147 | path[depth].p_ext = EXT_FIRST_EXTENT(eh); |
| 1148 | } else if (le32_to_cpu(newext->ee_block) |
| 1149 | > le32_to_cpu(nearex->ee_block)) { |
| 1150 | /* BUG_ON(newext->ee_block == nearex->ee_block); */ |
| 1151 | if (nearex != EXT_LAST_EXTENT(eh)) { |
| 1152 | len = EXT_MAX_EXTENT(eh) - nearex; |
| 1153 | len = (len - 1) * sizeof(struct ext4_extent); |
| 1154 | len = len < 0 ? 0 : len; |
| 1155 | ext_debug("insert %d:%d:%d after: nearest 0x%p, " |
| 1156 | "move %d from 0x%p to 0x%p\n", |
| 1157 | le32_to_cpu(newext->ee_block), |
| 1158 | le32_to_cpu(newext->ee_start), |
| 1159 | le16_to_cpu(newext->ee_len), |
| 1160 | nearex, len, nearex + 1, nearex + 2); |
| 1161 | memmove(nearex + 2, nearex + 1, len); |
| 1162 | } |
| 1163 | path[depth].p_ext = nearex + 1; |
| 1164 | } else { |
| 1165 | BUG_ON(newext->ee_block == nearex->ee_block); |
| 1166 | len = (EXT_MAX_EXTENT(eh) - nearex) * sizeof(struct ext4_extent); |
| 1167 | len = len < 0 ? 0 : len; |
| 1168 | ext_debug("insert %d:%d:%d before: nearest 0x%p, " |
| 1169 | "move %d from 0x%p to 0x%p\n", |
| 1170 | le32_to_cpu(newext->ee_block), |
| 1171 | le32_to_cpu(newext->ee_start), |
| 1172 | le16_to_cpu(newext->ee_len), |
| 1173 | nearex, len, nearex + 1, nearex + 2); |
| 1174 | memmove(nearex + 1, nearex, len); |
| 1175 | path[depth].p_ext = nearex; |
| 1176 | } |
| 1177 | |
| 1178 | eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)+1); |
| 1179 | nearex = path[depth].p_ext; |
| 1180 | nearex->ee_block = newext->ee_block; |
| 1181 | nearex->ee_start = newext->ee_start; |
| 1182 | nearex->ee_len = newext->ee_len; |
| 1183 | /* FIXME: support for large fs */ |
| 1184 | nearex->ee_start_hi = 0; |
| 1185 | |
| 1186 | merge: |
| 1187 | /* try to merge extents to the right */ |
| 1188 | while (nearex < EXT_LAST_EXTENT(eh)) { |
| 1189 | if (!ext4_can_extents_be_merged(inode, nearex, nearex + 1)) |
| 1190 | break; |
| 1191 | /* merge with next extent! */ |
| 1192 | nearex->ee_len = cpu_to_le16(le16_to_cpu(nearex->ee_len) |
| 1193 | + le16_to_cpu(nearex[1].ee_len)); |
| 1194 | if (nearex + 1 < EXT_LAST_EXTENT(eh)) { |
| 1195 | len = (EXT_LAST_EXTENT(eh) - nearex - 1) |
| 1196 | * sizeof(struct ext4_extent); |
| 1197 | memmove(nearex + 1, nearex + 2, len); |
| 1198 | } |
| 1199 | eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)-1); |
| 1200 | BUG_ON(eh->eh_entries == 0); |
| 1201 | } |
| 1202 | |
| 1203 | /* try to merge extents to the left */ |
| 1204 | |
| 1205 | /* time to correct all indexes above */ |
| 1206 | err = ext4_ext_correct_indexes(handle, inode, path); |
| 1207 | if (err) |
| 1208 | goto cleanup; |
| 1209 | |
| 1210 | err = ext4_ext_dirty(handle, inode, path + depth); |
| 1211 | |
| 1212 | cleanup: |
| 1213 | if (npath) { |
| 1214 | ext4_ext_drop_refs(npath); |
| 1215 | kfree(npath); |
| 1216 | } |
| 1217 | ext4_ext_tree_changed(inode); |
| 1218 | ext4_ext_invalidate_cache(inode); |
| 1219 | return err; |
| 1220 | } |
| 1221 | |
| 1222 | int ext4_ext_walk_space(struct inode *inode, unsigned long block, |
| 1223 | unsigned long num, ext_prepare_callback func, |
| 1224 | void *cbdata) |
| 1225 | { |
| 1226 | struct ext4_ext_path *path = NULL; |
| 1227 | struct ext4_ext_cache cbex; |
| 1228 | struct ext4_extent *ex; |
| 1229 | unsigned long next, start = 0, end = 0; |
| 1230 | unsigned long last = block + num; |
| 1231 | int depth, exists, err = 0; |
| 1232 | |
| 1233 | BUG_ON(func == NULL); |
| 1234 | BUG_ON(inode == NULL); |
| 1235 | |
| 1236 | while (block < last && block != EXT_MAX_BLOCK) { |
| 1237 | num = last - block; |
| 1238 | /* find extent for this block */ |
| 1239 | path = ext4_ext_find_extent(inode, block, path); |
| 1240 | if (IS_ERR(path)) { |
| 1241 | err = PTR_ERR(path); |
| 1242 | path = NULL; |
| 1243 | break; |
| 1244 | } |
| 1245 | |
| 1246 | depth = ext_depth(inode); |
| 1247 | BUG_ON(path[depth].p_hdr == NULL); |
| 1248 | ex = path[depth].p_ext; |
| 1249 | next = ext4_ext_next_allocated_block(path); |
| 1250 | |
| 1251 | exists = 0; |
| 1252 | if (!ex) { |
| 1253 | /* there is no extent yet, so try to allocate |
| 1254 | * all requested space */ |
| 1255 | start = block; |
| 1256 | end = block + num; |
| 1257 | } else if (le32_to_cpu(ex->ee_block) > block) { |
| 1258 | /* need to allocate space before found extent */ |
| 1259 | start = block; |
| 1260 | end = le32_to_cpu(ex->ee_block); |
| 1261 | if (block + num < end) |
| 1262 | end = block + num; |
| 1263 | } else if (block >= |
| 1264 | le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len)) { |
| 1265 | /* need to allocate space after found extent */ |
| 1266 | start = block; |
| 1267 | end = block + num; |
| 1268 | if (end >= next) |
| 1269 | end = next; |
| 1270 | } else if (block >= le32_to_cpu(ex->ee_block)) { |
| 1271 | /* |
| 1272 | * some part of requested space is covered |
| 1273 | * by found extent |
| 1274 | */ |
| 1275 | start = block; |
| 1276 | end = le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len); |
| 1277 | if (block + num < end) |
| 1278 | end = block + num; |
| 1279 | exists = 1; |
| 1280 | } else { |
| 1281 | BUG(); |
| 1282 | } |
| 1283 | BUG_ON(end <= start); |
| 1284 | |
| 1285 | if (!exists) { |
| 1286 | cbex.ec_block = start; |
| 1287 | cbex.ec_len = end - start; |
| 1288 | cbex.ec_start = 0; |
| 1289 | cbex.ec_type = EXT4_EXT_CACHE_GAP; |
| 1290 | } else { |
| 1291 | cbex.ec_block = le32_to_cpu(ex->ee_block); |
| 1292 | cbex.ec_len = le16_to_cpu(ex->ee_len); |
| 1293 | cbex.ec_start = le32_to_cpu(ex->ee_start); |
| 1294 | cbex.ec_type = EXT4_EXT_CACHE_EXTENT; |
| 1295 | } |
| 1296 | |
| 1297 | BUG_ON(cbex.ec_len == 0); |
| 1298 | err = func(inode, path, &cbex, cbdata); |
| 1299 | ext4_ext_drop_refs(path); |
| 1300 | |
| 1301 | if (err < 0) |
| 1302 | break; |
| 1303 | if (err == EXT_REPEAT) |
| 1304 | continue; |
| 1305 | else if (err == EXT_BREAK) { |
| 1306 | err = 0; |
| 1307 | break; |
| 1308 | } |
| 1309 | |
| 1310 | if (ext_depth(inode) != depth) { |
| 1311 | /* depth was changed. we have to realloc path */ |
| 1312 | kfree(path); |
| 1313 | path = NULL; |
| 1314 | } |
| 1315 | |
| 1316 | block = cbex.ec_block + cbex.ec_len; |
| 1317 | } |
| 1318 | |
| 1319 | if (path) { |
| 1320 | ext4_ext_drop_refs(path); |
| 1321 | kfree(path); |
| 1322 | } |
| 1323 | |
| 1324 | return err; |
| 1325 | } |
| 1326 | |
| 1327 | static inline void |
| 1328 | ext4_ext_put_in_cache(struct inode *inode, __u32 block, |
| 1329 | __u32 len, __u32 start, int type) |
| 1330 | { |
| 1331 | struct ext4_ext_cache *cex; |
| 1332 | BUG_ON(len == 0); |
| 1333 | cex = &EXT4_I(inode)->i_cached_extent; |
| 1334 | cex->ec_type = type; |
| 1335 | cex->ec_block = block; |
| 1336 | cex->ec_len = len; |
| 1337 | cex->ec_start = start; |
| 1338 | } |
| 1339 | |
| 1340 | /* |
| 1341 | * this routine calculate boundaries of the gap requested block fits into |
| 1342 | * and cache this gap |
| 1343 | */ |
| 1344 | static inline void |
| 1345 | ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path, |
| 1346 | unsigned long block) |
| 1347 | { |
| 1348 | int depth = ext_depth(inode); |
| 1349 | unsigned long lblock, len; |
| 1350 | struct ext4_extent *ex; |
| 1351 | |
| 1352 | ex = path[depth].p_ext; |
| 1353 | if (ex == NULL) { |
| 1354 | /* there is no extent yet, so gap is [0;-] */ |
| 1355 | lblock = 0; |
| 1356 | len = EXT_MAX_BLOCK; |
| 1357 | ext_debug("cache gap(whole file):"); |
| 1358 | } else if (block < le32_to_cpu(ex->ee_block)) { |
| 1359 | lblock = block; |
| 1360 | len = le32_to_cpu(ex->ee_block) - block; |
| 1361 | ext_debug("cache gap(before): %lu [%lu:%lu]", |
| 1362 | (unsigned long) block, |
| 1363 | (unsigned long) le32_to_cpu(ex->ee_block), |
| 1364 | (unsigned long) le16_to_cpu(ex->ee_len)); |
| 1365 | } else if (block >= le32_to_cpu(ex->ee_block) |
| 1366 | + le16_to_cpu(ex->ee_len)) { |
| 1367 | lblock = le32_to_cpu(ex->ee_block) |
| 1368 | + le16_to_cpu(ex->ee_len); |
| 1369 | len = ext4_ext_next_allocated_block(path); |
| 1370 | ext_debug("cache gap(after): [%lu:%lu] %lu", |
| 1371 | (unsigned long) le32_to_cpu(ex->ee_block), |
| 1372 | (unsigned long) le16_to_cpu(ex->ee_len), |
| 1373 | (unsigned long) block); |
| 1374 | BUG_ON(len == lblock); |
| 1375 | len = len - lblock; |
| 1376 | } else { |
| 1377 | lblock = len = 0; |
| 1378 | BUG(); |
| 1379 | } |
| 1380 | |
| 1381 | ext_debug(" -> %lu:%lu\n", (unsigned long) lblock, len); |
| 1382 | ext4_ext_put_in_cache(inode, lblock, len, 0, EXT4_EXT_CACHE_GAP); |
| 1383 | } |
| 1384 | |
| 1385 | static inline int |
| 1386 | ext4_ext_in_cache(struct inode *inode, unsigned long block, |
| 1387 | struct ext4_extent *ex) |
| 1388 | { |
| 1389 | struct ext4_ext_cache *cex; |
| 1390 | |
| 1391 | cex = &EXT4_I(inode)->i_cached_extent; |
| 1392 | |
| 1393 | /* has cache valid data? */ |
| 1394 | if (cex->ec_type == EXT4_EXT_CACHE_NO) |
| 1395 | return EXT4_EXT_CACHE_NO; |
| 1396 | |
| 1397 | BUG_ON(cex->ec_type != EXT4_EXT_CACHE_GAP && |
| 1398 | cex->ec_type != EXT4_EXT_CACHE_EXTENT); |
| 1399 | if (block >= cex->ec_block && block < cex->ec_block + cex->ec_len) { |
| 1400 | ex->ee_block = cpu_to_le32(cex->ec_block); |
| 1401 | ex->ee_start = cpu_to_le32(cex->ec_start); |
| 1402 | ex->ee_len = cpu_to_le16(cex->ec_len); |
| 1403 | ext_debug("%lu cached by %lu:%lu:%lu\n", |
| 1404 | (unsigned long) block, |
| 1405 | (unsigned long) cex->ec_block, |
| 1406 | (unsigned long) cex->ec_len, |
| 1407 | (unsigned long) cex->ec_start); |
| 1408 | return cex->ec_type; |
| 1409 | } |
| 1410 | |
| 1411 | /* not in cache */ |
| 1412 | return EXT4_EXT_CACHE_NO; |
| 1413 | } |
| 1414 | |
| 1415 | /* |
| 1416 | * routine removes index from the index block |
| 1417 | * it's used in truncate case only. thus all requests are for |
| 1418 | * last index in the block only |
| 1419 | */ |
| 1420 | int ext4_ext_rm_idx(handle_t *handle, struct inode *inode, |
| 1421 | struct ext4_ext_path *path) |
| 1422 | { |
| 1423 | struct buffer_head *bh; |
| 1424 | int err; |
| 1425 | unsigned long leaf; |
| 1426 | |
| 1427 | /* free index block */ |
| 1428 | path--; |
| 1429 | leaf = le32_to_cpu(path->p_idx->ei_leaf); |
| 1430 | BUG_ON(path->p_hdr->eh_entries == 0); |
| 1431 | if ((err = ext4_ext_get_access(handle, inode, path))) |
| 1432 | return err; |
| 1433 | path->p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(path->p_hdr->eh_entries)-1); |
| 1434 | if ((err = ext4_ext_dirty(handle, inode, path))) |
| 1435 | return err; |
| 1436 | ext_debug("index is empty, remove it, free block %lu\n", leaf); |
| 1437 | bh = sb_find_get_block(inode->i_sb, leaf); |
| 1438 | ext4_forget(handle, 1, inode, bh, leaf); |
| 1439 | ext4_free_blocks(handle, inode, leaf, 1); |
| 1440 | return err; |
| 1441 | } |
| 1442 | |
| 1443 | /* |
| 1444 | * This routine returns max. credits extent tree can consume. |
| 1445 | * It should be OK for low-performance paths like ->writepage() |
| 1446 | * To allow many writing process to fit a single transaction, |
| 1447 | * caller should calculate credits under truncate_mutex and |
| 1448 | * pass actual path. |
| 1449 | */ |
| 1450 | int inline ext4_ext_calc_credits_for_insert(struct inode *inode, |
| 1451 | struct ext4_ext_path *path) |
| 1452 | { |
| 1453 | int depth, needed; |
| 1454 | |
| 1455 | if (path) { |
| 1456 | /* probably there is space in leaf? */ |
| 1457 | depth = ext_depth(inode); |
| 1458 | if (le16_to_cpu(path[depth].p_hdr->eh_entries) |
| 1459 | < le16_to_cpu(path[depth].p_hdr->eh_max)) |
| 1460 | return 1; |
| 1461 | } |
| 1462 | |
| 1463 | /* |
| 1464 | * given 32bit logical block (4294967296 blocks), max. tree |
| 1465 | * can be 4 levels in depth -- 4 * 340^4 == 53453440000. |
| 1466 | * let's also add one more level for imbalance. |
| 1467 | */ |
| 1468 | depth = 5; |
| 1469 | |
| 1470 | /* allocation of new data block(s) */ |
| 1471 | needed = 2; |
| 1472 | |
| 1473 | /* |
| 1474 | * tree can be full, so it'd need to grow in depth: |
| 1475 | * allocation + old root + new root |
| 1476 | */ |
| 1477 | needed += 2 + 1 + 1; |
| 1478 | |
| 1479 | /* |
| 1480 | * Index split can happen, we'd need: |
| 1481 | * allocate intermediate indexes (bitmap + group) |
| 1482 | * + change two blocks at each level, but root (already included) |
| 1483 | */ |
| 1484 | needed = (depth * 2) + (depth * 2); |
| 1485 | |
| 1486 | /* any allocation modifies superblock */ |
| 1487 | needed += 1; |
| 1488 | |
| 1489 | return needed; |
| 1490 | } |
| 1491 | |
| 1492 | static int ext4_remove_blocks(handle_t *handle, struct inode *inode, |
| 1493 | struct ext4_extent *ex, |
| 1494 | unsigned long from, unsigned long to) |
| 1495 | { |
| 1496 | struct buffer_head *bh; |
| 1497 | int i; |
| 1498 | |
| 1499 | #ifdef EXTENTS_STATS |
| 1500 | { |
| 1501 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| 1502 | unsigned short ee_len = le16_to_cpu(ex->ee_len); |
| 1503 | spin_lock(&sbi->s_ext_stats_lock); |
| 1504 | sbi->s_ext_blocks += ee_len; |
| 1505 | sbi->s_ext_extents++; |
| 1506 | if (ee_len < sbi->s_ext_min) |
| 1507 | sbi->s_ext_min = ee_len; |
| 1508 | if (ee_len > sbi->s_ext_max) |
| 1509 | sbi->s_ext_max = ee_len; |
| 1510 | if (ext_depth(inode) > sbi->s_depth_max) |
| 1511 | sbi->s_depth_max = ext_depth(inode); |
| 1512 | spin_unlock(&sbi->s_ext_stats_lock); |
| 1513 | } |
| 1514 | #endif |
| 1515 | if (from >= le32_to_cpu(ex->ee_block) |
| 1516 | && to == le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - 1) { |
| 1517 | /* tail removal */ |
| 1518 | unsigned long num, start; |
| 1519 | num = le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - from; |
| 1520 | start = le32_to_cpu(ex->ee_start) + le16_to_cpu(ex->ee_len) - num; |
| 1521 | ext_debug("free last %lu blocks starting %lu\n", num, start); |
| 1522 | for (i = 0; i < num; i++) { |
| 1523 | bh = sb_find_get_block(inode->i_sb, start + i); |
| 1524 | ext4_forget(handle, 0, inode, bh, start + i); |
| 1525 | } |
| 1526 | ext4_free_blocks(handle, inode, start, num); |
| 1527 | } else if (from == le32_to_cpu(ex->ee_block) |
| 1528 | && to <= le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - 1) { |
| 1529 | printk("strange request: removal %lu-%lu from %u:%u\n", |
| 1530 | from, to, le32_to_cpu(ex->ee_block), le16_to_cpu(ex->ee_len)); |
| 1531 | } else { |
| 1532 | printk("strange request: removal(2) %lu-%lu from %u:%u\n", |
| 1533 | from, to, le32_to_cpu(ex->ee_block), le16_to_cpu(ex->ee_len)); |
| 1534 | } |
| 1535 | return 0; |
| 1536 | } |
| 1537 | |
| 1538 | static int |
| 1539 | ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, |
| 1540 | struct ext4_ext_path *path, unsigned long start) |
| 1541 | { |
| 1542 | int err = 0, correct_index = 0; |
| 1543 | int depth = ext_depth(inode), credits; |
| 1544 | struct ext4_extent_header *eh; |
| 1545 | unsigned a, b, block, num; |
| 1546 | unsigned long ex_ee_block; |
| 1547 | unsigned short ex_ee_len; |
| 1548 | struct ext4_extent *ex; |
| 1549 | |
| 1550 | ext_debug("truncate since %lu in leaf\n", start); |
| 1551 | if (!path[depth].p_hdr) |
| 1552 | path[depth].p_hdr = ext_block_hdr(path[depth].p_bh); |
| 1553 | eh = path[depth].p_hdr; |
| 1554 | BUG_ON(eh == NULL); |
| 1555 | BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max)); |
| 1556 | BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC); |
| 1557 | |
| 1558 | /* find where to start removing */ |
| 1559 | ex = EXT_LAST_EXTENT(eh); |
| 1560 | |
| 1561 | ex_ee_block = le32_to_cpu(ex->ee_block); |
| 1562 | ex_ee_len = le16_to_cpu(ex->ee_len); |
| 1563 | |
| 1564 | while (ex >= EXT_FIRST_EXTENT(eh) && |
| 1565 | ex_ee_block + ex_ee_len > start) { |
| 1566 | ext_debug("remove ext %lu:%u\n", ex_ee_block, ex_ee_len); |
| 1567 | path[depth].p_ext = ex; |
| 1568 | |
| 1569 | a = ex_ee_block > start ? ex_ee_block : start; |
| 1570 | b = ex_ee_block + ex_ee_len - 1 < EXT_MAX_BLOCK ? |
| 1571 | ex_ee_block + ex_ee_len - 1 : EXT_MAX_BLOCK; |
| 1572 | |
| 1573 | ext_debug(" border %u:%u\n", a, b); |
| 1574 | |
| 1575 | if (a != ex_ee_block && b != ex_ee_block + ex_ee_len - 1) { |
| 1576 | block = 0; |
| 1577 | num = 0; |
| 1578 | BUG(); |
| 1579 | } else if (a != ex_ee_block) { |
| 1580 | /* remove tail of the extent */ |
| 1581 | block = ex_ee_block; |
| 1582 | num = a - block; |
| 1583 | } else if (b != ex_ee_block + ex_ee_len - 1) { |
| 1584 | /* remove head of the extent */ |
| 1585 | block = a; |
| 1586 | num = b - a; |
| 1587 | /* there is no "make a hole" API yet */ |
| 1588 | BUG(); |
| 1589 | } else { |
| 1590 | /* remove whole extent: excellent! */ |
| 1591 | block = ex_ee_block; |
| 1592 | num = 0; |
| 1593 | BUG_ON(a != ex_ee_block); |
| 1594 | BUG_ON(b != ex_ee_block + ex_ee_len - 1); |
| 1595 | } |
| 1596 | |
| 1597 | /* at present, extent can't cross block group */ |
| 1598 | /* leaf + bitmap + group desc + sb + inode */ |
| 1599 | credits = 5; |
| 1600 | if (ex == EXT_FIRST_EXTENT(eh)) { |
| 1601 | correct_index = 1; |
| 1602 | credits += (ext_depth(inode)) + 1; |
| 1603 | } |
| 1604 | #ifdef CONFIG_QUOTA |
| 1605 | credits += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb); |
| 1606 | #endif |
| 1607 | |
| 1608 | handle = ext4_ext_journal_restart(handle, credits); |
| 1609 | if (IS_ERR(handle)) { |
| 1610 | err = PTR_ERR(handle); |
| 1611 | goto out; |
| 1612 | } |
| 1613 | |
| 1614 | err = ext4_ext_get_access(handle, inode, path + depth); |
| 1615 | if (err) |
| 1616 | goto out; |
| 1617 | |
| 1618 | err = ext4_remove_blocks(handle, inode, ex, a, b); |
| 1619 | if (err) |
| 1620 | goto out; |
| 1621 | |
| 1622 | if (num == 0) { |
| 1623 | /* this extent is removed entirely mark slot unused */ |
| 1624 | ex->ee_start = 0; |
| 1625 | eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)-1); |
| 1626 | } |
| 1627 | |
| 1628 | ex->ee_block = cpu_to_le32(block); |
| 1629 | ex->ee_len = cpu_to_le16(num); |
| 1630 | |
| 1631 | err = ext4_ext_dirty(handle, inode, path + depth); |
| 1632 | if (err) |
| 1633 | goto out; |
| 1634 | |
| 1635 | ext_debug("new extent: %u:%u:%u\n", block, num, |
| 1636 | le32_to_cpu(ex->ee_start)); |
| 1637 | ex--; |
| 1638 | ex_ee_block = le32_to_cpu(ex->ee_block); |
| 1639 | ex_ee_len = le16_to_cpu(ex->ee_len); |
| 1640 | } |
| 1641 | |
| 1642 | if (correct_index && eh->eh_entries) |
| 1643 | err = ext4_ext_correct_indexes(handle, inode, path); |
| 1644 | |
| 1645 | /* if this leaf is free, then we should |
| 1646 | * remove it from index block above */ |
| 1647 | if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL) |
| 1648 | err = ext4_ext_rm_idx(handle, inode, path + depth); |
| 1649 | |
| 1650 | out: |
| 1651 | return err; |
| 1652 | } |
| 1653 | |
| 1654 | /* |
| 1655 | * returns 1 if current index have to be freed (even partial) |
| 1656 | */ |
| 1657 | static int inline |
| 1658 | ext4_ext_more_to_rm(struct ext4_ext_path *path) |
| 1659 | { |
| 1660 | BUG_ON(path->p_idx == NULL); |
| 1661 | |
| 1662 | if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr)) |
| 1663 | return 0; |
| 1664 | |
| 1665 | /* |
| 1666 | * if truncate on deeper level happened it it wasn't partial |
| 1667 | * so we have to consider current index for truncation |
| 1668 | */ |
| 1669 | if (le16_to_cpu(path->p_hdr->eh_entries) == path->p_block) |
| 1670 | return 0; |
| 1671 | return 1; |
| 1672 | } |
| 1673 | |
| 1674 | int ext4_ext_remove_space(struct inode *inode, unsigned long start) |
| 1675 | { |
| 1676 | struct super_block *sb = inode->i_sb; |
| 1677 | int depth = ext_depth(inode); |
| 1678 | struct ext4_ext_path *path; |
| 1679 | handle_t *handle; |
| 1680 | int i = 0, err = 0; |
| 1681 | |
| 1682 | ext_debug("truncate since %lu\n", start); |
| 1683 | |
| 1684 | /* probably first extent we're gonna free will be last in block */ |
| 1685 | handle = ext4_journal_start(inode, depth + 1); |
| 1686 | if (IS_ERR(handle)) |
| 1687 | return PTR_ERR(handle); |
| 1688 | |
| 1689 | ext4_ext_invalidate_cache(inode); |
| 1690 | |
| 1691 | /* |
| 1692 | * we start scanning from right side freeing all the blocks |
| 1693 | * after i_size and walking into the deep |
| 1694 | */ |
| 1695 | path = kmalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_KERNEL); |
| 1696 | if (path == NULL) { |
| 1697 | ext4_journal_stop(handle); |
| 1698 | return -ENOMEM; |
| 1699 | } |
| 1700 | memset(path, 0, sizeof(struct ext4_ext_path) * (depth + 1)); |
| 1701 | path[0].p_hdr = ext_inode_hdr(inode); |
| 1702 | if (ext4_ext_check_header(__FUNCTION__, inode, path[0].p_hdr)) { |
| 1703 | err = -EIO; |
| 1704 | goto out; |
| 1705 | } |
| 1706 | path[0].p_depth = depth; |
| 1707 | |
| 1708 | while (i >= 0 && err == 0) { |
| 1709 | if (i == depth) { |
| 1710 | /* this is leaf block */ |
| 1711 | err = ext4_ext_rm_leaf(handle, inode, path, start); |
| 1712 | /* root level have p_bh == NULL, brelse() eats this */ |
| 1713 | brelse(path[i].p_bh); |
| 1714 | path[i].p_bh = NULL; |
| 1715 | i--; |
| 1716 | continue; |
| 1717 | } |
| 1718 | |
| 1719 | /* this is index block */ |
| 1720 | if (!path[i].p_hdr) { |
| 1721 | ext_debug("initialize header\n"); |
| 1722 | path[i].p_hdr = ext_block_hdr(path[i].p_bh); |
| 1723 | if (ext4_ext_check_header(__FUNCTION__, inode, |
| 1724 | path[i].p_hdr)) { |
| 1725 | err = -EIO; |
| 1726 | goto out; |
| 1727 | } |
| 1728 | } |
| 1729 | |
| 1730 | BUG_ON(le16_to_cpu(path[i].p_hdr->eh_entries) |
| 1731 | > le16_to_cpu(path[i].p_hdr->eh_max)); |
| 1732 | BUG_ON(path[i].p_hdr->eh_magic != EXT4_EXT_MAGIC); |
| 1733 | |
| 1734 | if (!path[i].p_idx) { |
| 1735 | /* this level hasn't touched yet */ |
| 1736 | path[i].p_idx = EXT_LAST_INDEX(path[i].p_hdr); |
| 1737 | path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries)+1; |
| 1738 | ext_debug("init index ptr: hdr 0x%p, num %d\n", |
| 1739 | path[i].p_hdr, |
| 1740 | le16_to_cpu(path[i].p_hdr->eh_entries)); |
| 1741 | } else { |
| 1742 | /* we've already was here, see at next index */ |
| 1743 | path[i].p_idx--; |
| 1744 | } |
| 1745 | |
| 1746 | ext_debug("level %d - index, first 0x%p, cur 0x%p\n", |
| 1747 | i, EXT_FIRST_INDEX(path[i].p_hdr), |
| 1748 | path[i].p_idx); |
| 1749 | if (ext4_ext_more_to_rm(path + i)) { |
| 1750 | /* go to the next level */ |
| 1751 | ext_debug("move to level %d (block %d)\n", |
| 1752 | i + 1, le32_to_cpu(path[i].p_idx->ei_leaf)); |
| 1753 | memset(path + i + 1, 0, sizeof(*path)); |
| 1754 | path[i+1].p_bh = |
| 1755 | sb_bread(sb, le32_to_cpu(path[i].p_idx->ei_leaf)); |
| 1756 | if (!path[i+1].p_bh) { |
| 1757 | /* should we reset i_size? */ |
| 1758 | err = -EIO; |
| 1759 | break; |
| 1760 | } |
| 1761 | |
| 1762 | /* put actual number of indexes to know is this |
| 1763 | * number got changed at the next iteration */ |
| 1764 | path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries); |
| 1765 | i++; |
| 1766 | } else { |
| 1767 | /* we finish processing this index, go up */ |
| 1768 | if (path[i].p_hdr->eh_entries == 0 && i > 0) { |
| 1769 | /* index is empty, remove it |
| 1770 | * handle must be already prepared by the |
| 1771 | * truncatei_leaf() */ |
| 1772 | err = ext4_ext_rm_idx(handle, inode, path + i); |
| 1773 | } |
| 1774 | /* root level have p_bh == NULL, brelse() eats this */ |
| 1775 | brelse(path[i].p_bh); |
| 1776 | path[i].p_bh = NULL; |
| 1777 | i--; |
| 1778 | ext_debug("return to level %d\n", i); |
| 1779 | } |
| 1780 | } |
| 1781 | |
| 1782 | /* TODO: flexible tree reduction should be here */ |
| 1783 | if (path->p_hdr->eh_entries == 0) { |
| 1784 | /* |
| 1785 | * truncate to zero freed all the tree |
| 1786 | * so, we need to correct eh_depth |
| 1787 | */ |
| 1788 | err = ext4_ext_get_access(handle, inode, path); |
| 1789 | if (err == 0) { |
| 1790 | ext_inode_hdr(inode)->eh_depth = 0; |
| 1791 | ext_inode_hdr(inode)->eh_max = |
| 1792 | cpu_to_le16(ext4_ext_space_root(inode)); |
| 1793 | err = ext4_ext_dirty(handle, inode, path); |
| 1794 | } |
| 1795 | } |
| 1796 | out: |
| 1797 | ext4_ext_tree_changed(inode); |
| 1798 | ext4_ext_drop_refs(path); |
| 1799 | kfree(path); |
| 1800 | ext4_journal_stop(handle); |
| 1801 | |
| 1802 | return err; |
| 1803 | } |
| 1804 | |
| 1805 | /* |
| 1806 | * called at mount time |
| 1807 | */ |
| 1808 | void ext4_ext_init(struct super_block *sb) |
| 1809 | { |
| 1810 | /* |
| 1811 | * possible initialization would be here |
| 1812 | */ |
| 1813 | |
| 1814 | if (test_opt(sb, EXTENTS)) { |
| 1815 | printk("EXT4-fs: file extents enabled"); |
| 1816 | #ifdef AGRESSIVE_TEST |
| 1817 | printk(", agressive tests"); |
| 1818 | #endif |
| 1819 | #ifdef CHECK_BINSEARCH |
| 1820 | printk(", check binsearch"); |
| 1821 | #endif |
| 1822 | #ifdef EXTENTS_STATS |
| 1823 | printk(", stats"); |
| 1824 | #endif |
| 1825 | printk("\n"); |
| 1826 | #ifdef EXTENTS_STATS |
| 1827 | spin_lock_init(&EXT4_SB(sb)->s_ext_stats_lock); |
| 1828 | EXT4_SB(sb)->s_ext_min = 1 << 30; |
| 1829 | EXT4_SB(sb)->s_ext_max = 0; |
| 1830 | #endif |
| 1831 | } |
| 1832 | } |
| 1833 | |
| 1834 | /* |
| 1835 | * called at umount time |
| 1836 | */ |
| 1837 | void ext4_ext_release(struct super_block *sb) |
| 1838 | { |
| 1839 | if (!test_opt(sb, EXTENTS)) |
| 1840 | return; |
| 1841 | |
| 1842 | #ifdef EXTENTS_STATS |
| 1843 | if (EXT4_SB(sb)->s_ext_blocks && EXT4_SB(sb)->s_ext_extents) { |
| 1844 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 1845 | printk(KERN_ERR "EXT4-fs: %lu blocks in %lu extents (%lu ave)\n", |
| 1846 | sbi->s_ext_blocks, sbi->s_ext_extents, |
| 1847 | sbi->s_ext_blocks / sbi->s_ext_extents); |
| 1848 | printk(KERN_ERR "EXT4-fs: extents: %lu min, %lu max, max depth %lu\n", |
| 1849 | sbi->s_ext_min, sbi->s_ext_max, sbi->s_depth_max); |
| 1850 | } |
| 1851 | #endif |
| 1852 | } |
| 1853 | |
| 1854 | int ext4_ext_get_blocks(handle_t *handle, struct inode *inode, sector_t iblock, |
| 1855 | unsigned long max_blocks, struct buffer_head *bh_result, |
| 1856 | int create, int extend_disksize) |
| 1857 | { |
| 1858 | struct ext4_ext_path *path = NULL; |
| 1859 | struct ext4_extent newex, *ex; |
| 1860 | int goal, newblock, err = 0, depth; |
| 1861 | unsigned long allocated = 0; |
| 1862 | |
| 1863 | __clear_bit(BH_New, &bh_result->b_state); |
| 1864 | ext_debug("blocks %d/%lu requested for inode %u\n", (int) iblock, |
| 1865 | max_blocks, (unsigned) inode->i_ino); |
| 1866 | mutex_lock(&EXT4_I(inode)->truncate_mutex); |
| 1867 | |
| 1868 | /* check in cache */ |
| 1869 | if ((goal = ext4_ext_in_cache(inode, iblock, &newex))) { |
| 1870 | if (goal == EXT4_EXT_CACHE_GAP) { |
| 1871 | if (!create) { |
| 1872 | /* block isn't allocated yet and |
| 1873 | * user don't want to allocate it */ |
| 1874 | goto out2; |
| 1875 | } |
| 1876 | /* we should allocate requested block */ |
| 1877 | } else if (goal == EXT4_EXT_CACHE_EXTENT) { |
| 1878 | /* block is already allocated */ |
| 1879 | newblock = iblock |
| 1880 | - le32_to_cpu(newex.ee_block) |
| 1881 | + le32_to_cpu(newex.ee_start); |
| 1882 | /* number of remain blocks in the extent */ |
| 1883 | allocated = le16_to_cpu(newex.ee_len) - |
| 1884 | (iblock - le32_to_cpu(newex.ee_block)); |
| 1885 | goto out; |
| 1886 | } else { |
| 1887 | BUG(); |
| 1888 | } |
| 1889 | } |
| 1890 | |
| 1891 | /* find extent for this block */ |
| 1892 | path = ext4_ext_find_extent(inode, iblock, NULL); |
| 1893 | if (IS_ERR(path)) { |
| 1894 | err = PTR_ERR(path); |
| 1895 | path = NULL; |
| 1896 | goto out2; |
| 1897 | } |
| 1898 | |
| 1899 | depth = ext_depth(inode); |
| 1900 | |
| 1901 | /* |
| 1902 | * consistent leaf must not be empty |
| 1903 | * this situations is possible, though, _during_ tree modification |
| 1904 | * this is why assert can't be put in ext4_ext_find_extent() |
| 1905 | */ |
| 1906 | BUG_ON(path[depth].p_ext == NULL && depth != 0); |
| 1907 | |
| 1908 | if ((ex = path[depth].p_ext)) { |
| 1909 | unsigned long ee_block = le32_to_cpu(ex->ee_block); |
| 1910 | unsigned long ee_start = le32_to_cpu(ex->ee_start); |
| 1911 | unsigned short ee_len = le16_to_cpu(ex->ee_len); |
| 1912 | /* if found exent covers block, simple return it */ |
| 1913 | if (iblock >= ee_block && iblock < ee_block + ee_len) { |
| 1914 | newblock = iblock - ee_block + ee_start; |
| 1915 | /* number of remain blocks in the extent */ |
| 1916 | allocated = ee_len - (iblock - ee_block); |
| 1917 | ext_debug("%d fit into %lu:%d -> %d\n", (int) iblock, |
| 1918 | ee_block, ee_len, newblock); |
| 1919 | ext4_ext_put_in_cache(inode, ee_block, ee_len, |
| 1920 | ee_start, EXT4_EXT_CACHE_EXTENT); |
| 1921 | goto out; |
| 1922 | } |
| 1923 | } |
| 1924 | |
| 1925 | /* |
| 1926 | * requested block isn't allocated yet |
| 1927 | * we couldn't try to create block if create flag is zero |
| 1928 | */ |
| 1929 | if (!create) { |
| 1930 | /* put just found gap into cache to speedup subsequest reqs */ |
| 1931 | ext4_ext_put_gap_in_cache(inode, path, iblock); |
| 1932 | goto out2; |
| 1933 | } |
| 1934 | /* |
| 1935 | * Okay, we need to do block allocation. Lazily initialize the block |
| 1936 | * allocation info here if necessary |
| 1937 | */ |
| 1938 | if (S_ISREG(inode->i_mode) && (!EXT4_I(inode)->i_block_alloc_info)) |
| 1939 | ext4_init_block_alloc_info(inode); |
| 1940 | |
| 1941 | /* allocate new block */ |
| 1942 | goal = ext4_ext_find_goal(inode, path, iblock); |
| 1943 | allocated = max_blocks; |
| 1944 | newblock = ext4_new_blocks(handle, inode, goal, &allocated, &err); |
| 1945 | if (!newblock) |
| 1946 | goto out2; |
| 1947 | ext_debug("allocate new block: goal %d, found %d/%lu\n", |
| 1948 | goal, newblock, allocated); |
| 1949 | |
| 1950 | /* try to insert new extent into found leaf and return */ |
| 1951 | newex.ee_block = cpu_to_le32(iblock); |
| 1952 | newex.ee_start = cpu_to_le32(newblock); |
| 1953 | newex.ee_len = cpu_to_le16(allocated); |
| 1954 | err = ext4_ext_insert_extent(handle, inode, path, &newex); |
| 1955 | if (err) |
| 1956 | goto out2; |
| 1957 | |
| 1958 | if (extend_disksize && inode->i_size > EXT4_I(inode)->i_disksize) |
| 1959 | EXT4_I(inode)->i_disksize = inode->i_size; |
| 1960 | |
| 1961 | /* previous routine could use block we allocated */ |
| 1962 | newblock = le32_to_cpu(newex.ee_start); |
| 1963 | __set_bit(BH_New, &bh_result->b_state); |
| 1964 | |
| 1965 | ext4_ext_put_in_cache(inode, iblock, allocated, newblock, |
| 1966 | EXT4_EXT_CACHE_EXTENT); |
| 1967 | out: |
| 1968 | if (allocated > max_blocks) |
| 1969 | allocated = max_blocks; |
| 1970 | ext4_ext_show_leaf(inode, path); |
| 1971 | __set_bit(BH_Mapped, &bh_result->b_state); |
| 1972 | bh_result->b_bdev = inode->i_sb->s_bdev; |
| 1973 | bh_result->b_blocknr = newblock; |
| 1974 | out2: |
| 1975 | if (path) { |
| 1976 | ext4_ext_drop_refs(path); |
| 1977 | kfree(path); |
| 1978 | } |
| 1979 | mutex_unlock(&EXT4_I(inode)->truncate_mutex); |
| 1980 | |
| 1981 | return err ? err : allocated; |
| 1982 | } |
| 1983 | |
| 1984 | void ext4_ext_truncate(struct inode * inode, struct page *page) |
| 1985 | { |
| 1986 | struct address_space *mapping = inode->i_mapping; |
| 1987 | struct super_block *sb = inode->i_sb; |
| 1988 | unsigned long last_block; |
| 1989 | handle_t *handle; |
| 1990 | int err = 0; |
| 1991 | |
| 1992 | /* |
| 1993 | * probably first extent we're gonna free will be last in block |
| 1994 | */ |
| 1995 | err = ext4_writepage_trans_blocks(inode) + 3; |
| 1996 | handle = ext4_journal_start(inode, err); |
| 1997 | if (IS_ERR(handle)) { |
| 1998 | if (page) { |
| 1999 | clear_highpage(page); |
| 2000 | flush_dcache_page(page); |
| 2001 | unlock_page(page); |
| 2002 | page_cache_release(page); |
| 2003 | } |
| 2004 | return; |
| 2005 | } |
| 2006 | |
| 2007 | if (page) |
| 2008 | ext4_block_truncate_page(handle, page, mapping, inode->i_size); |
| 2009 | |
| 2010 | mutex_lock(&EXT4_I(inode)->truncate_mutex); |
| 2011 | ext4_ext_invalidate_cache(inode); |
| 2012 | |
| 2013 | /* |
| 2014 | * TODO: optimization is possible here |
| 2015 | * probably we need not scaning at all, |
| 2016 | * because page truncation is enough |
| 2017 | */ |
| 2018 | if (ext4_orphan_add(handle, inode)) |
| 2019 | goto out_stop; |
| 2020 | |
| 2021 | /* we have to know where to truncate from in crash case */ |
| 2022 | EXT4_I(inode)->i_disksize = inode->i_size; |
| 2023 | ext4_mark_inode_dirty(handle, inode); |
| 2024 | |
| 2025 | last_block = (inode->i_size + sb->s_blocksize - 1) |
| 2026 | >> EXT4_BLOCK_SIZE_BITS(sb); |
| 2027 | err = ext4_ext_remove_space(inode, last_block); |
| 2028 | |
| 2029 | /* In a multi-transaction truncate, we only make the final |
| 2030 | * transaction synchronous */ |
| 2031 | if (IS_SYNC(inode)) |
| 2032 | handle->h_sync = 1; |
| 2033 | |
| 2034 | out_stop: |
| 2035 | /* |
| 2036 | * If this was a simple ftruncate(), and the file will remain alive |
| 2037 | * then we need to clear up the orphan record which we created above. |
| 2038 | * However, if this was a real unlink then we were called by |
| 2039 | * ext4_delete_inode(), and we allow that function to clean up the |
| 2040 | * orphan info for us. |
| 2041 | */ |
| 2042 | if (inode->i_nlink) |
| 2043 | ext4_orphan_del(handle, inode); |
| 2044 | |
| 2045 | mutex_unlock(&EXT4_I(inode)->truncate_mutex); |
| 2046 | ext4_journal_stop(handle); |
| 2047 | } |
| 2048 | |
| 2049 | /* |
| 2050 | * this routine calculate max number of blocks we could modify |
| 2051 | * in order to allocate new block for an inode |
| 2052 | */ |
| 2053 | int ext4_ext_writepage_trans_blocks(struct inode *inode, int num) |
| 2054 | { |
| 2055 | int needed; |
| 2056 | |
| 2057 | needed = ext4_ext_calc_credits_for_insert(inode, NULL); |
| 2058 | |
| 2059 | /* caller want to allocate num blocks, but note it includes sb */ |
| 2060 | needed = needed * num - (num - 1); |
| 2061 | |
| 2062 | #ifdef CONFIG_QUOTA |
| 2063 | needed += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb); |
| 2064 | #endif |
| 2065 | |
| 2066 | return needed; |
| 2067 | } |
| 2068 | |
| 2069 | EXPORT_SYMBOL(ext4_mark_inode_dirty); |
| 2070 | EXPORT_SYMBOL(ext4_ext_invalidate_cache); |
| 2071 | EXPORT_SYMBOL(ext4_ext_insert_extent); |
| 2072 | EXPORT_SYMBOL(ext4_ext_walk_space); |
| 2073 | EXPORT_SYMBOL(ext4_ext_find_goal); |
| 2074 | EXPORT_SYMBOL(ext4_ext_calc_credits_for_insert); |
| 2075 | |