| 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* |
| 3 | * linux/fs/ext4/namei.c |
| 4 | * |
| 5 | * Copyright (C) 1992, 1993, 1994, 1995 |
| 6 | * Remy Card (card@masi.ibp.fr) |
| 7 | * Laboratoire MASI - Institut Blaise Pascal |
| 8 | * Universite Pierre et Marie Curie (Paris VI) |
| 9 | * |
| 10 | * from |
| 11 | * |
| 12 | * linux/fs/minix/namei.c |
| 13 | * |
| 14 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 15 | * |
| 16 | * Big-endian to little-endian byte-swapping/bitmaps by |
| 17 | * David S. Miller (davem@caip.rutgers.edu), 1995 |
| 18 | * Directory entry file type support and forward compatibility hooks |
| 19 | * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998 |
| 20 | * Hash Tree Directory indexing (c) |
| 21 | * Daniel Phillips, 2001 |
| 22 | * Hash Tree Directory indexing porting |
| 23 | * Christopher Li, 2002 |
| 24 | * Hash Tree Directory indexing cleanup |
| 25 | * Theodore Ts'o, 2002 |
| 26 | */ |
| 27 | |
| 28 | #include <linux/fs.h> |
| 29 | #include <linux/pagemap.h> |
| 30 | #include <linux/time.h> |
| 31 | #include <linux/fcntl.h> |
| 32 | #include <linux/stat.h> |
| 33 | #include <linux/string.h> |
| 34 | #include <linux/quotaops.h> |
| 35 | #include <linux/buffer_head.h> |
| 36 | #include <linux/bio.h> |
| 37 | #include "ext4.h" |
| 38 | #include "ext4_jbd2.h" |
| 39 | |
| 40 | #include "xattr.h" |
| 41 | #include "acl.h" |
| 42 | |
| 43 | #include <trace/events/ext4.h> |
| 44 | /* |
| 45 | * define how far ahead to read directories while searching them. |
| 46 | */ |
| 47 | #define NAMEI_RA_CHUNKS 2 |
| 48 | #define NAMEI_RA_BLOCKS 4 |
| 49 | #define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS) |
| 50 | |
| 51 | static struct buffer_head *ext4_append(handle_t *handle, |
| 52 | struct inode *inode, |
| 53 | ext4_lblk_t *block) |
| 54 | { |
| 55 | struct buffer_head *bh; |
| 56 | int err; |
| 57 | |
| 58 | if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb && |
| 59 | ((inode->i_size >> 10) >= |
| 60 | EXT4_SB(inode->i_sb)->s_max_dir_size_kb))) |
| 61 | return ERR_PTR(-ENOSPC); |
| 62 | |
| 63 | *block = inode->i_size >> inode->i_sb->s_blocksize_bits; |
| 64 | |
| 65 | bh = ext4_bread(handle, inode, *block, EXT4_GET_BLOCKS_CREATE); |
| 66 | if (IS_ERR(bh)) |
| 67 | return bh; |
| 68 | inode->i_size += inode->i_sb->s_blocksize; |
| 69 | EXT4_I(inode)->i_disksize = inode->i_size; |
| 70 | BUFFER_TRACE(bh, "get_write_access"); |
| 71 | err = ext4_journal_get_write_access(handle, bh); |
| 72 | if (err) { |
| 73 | brelse(bh); |
| 74 | ext4_std_error(inode->i_sb, err); |
| 75 | return ERR_PTR(err); |
| 76 | } |
| 77 | return bh; |
| 78 | } |
| 79 | |
| 80 | static int ext4_dx_csum_verify(struct inode *inode, |
| 81 | struct ext4_dir_entry *dirent); |
| 82 | |
| 83 | typedef enum { |
| 84 | EITHER, INDEX, DIRENT |
| 85 | } dirblock_type_t; |
| 86 | |
| 87 | #define ext4_read_dirblock(inode, block, type) \ |
| 88 | __ext4_read_dirblock((inode), (block), (type), __func__, __LINE__) |
| 89 | |
| 90 | static struct buffer_head *__ext4_read_dirblock(struct inode *inode, |
| 91 | ext4_lblk_t block, |
| 92 | dirblock_type_t type, |
| 93 | const char *func, |
| 94 | unsigned int line) |
| 95 | { |
| 96 | struct buffer_head *bh; |
| 97 | struct ext4_dir_entry *dirent; |
| 98 | int is_dx_block = 0; |
| 99 | |
| 100 | bh = ext4_bread(NULL, inode, block, 0); |
| 101 | if (IS_ERR(bh)) { |
| 102 | __ext4_warning(inode->i_sb, func, line, |
| 103 | "inode #%lu: lblock %lu: comm %s: " |
| 104 | "error %ld reading directory block", |
| 105 | inode->i_ino, (unsigned long)block, |
| 106 | current->comm, PTR_ERR(bh)); |
| 107 | |
| 108 | return bh; |
| 109 | } |
| 110 | if (!bh) { |
| 111 | ext4_error_inode(inode, func, line, block, |
| 112 | "Directory hole found"); |
| 113 | return ERR_PTR(-EFSCORRUPTED); |
| 114 | } |
| 115 | dirent = (struct ext4_dir_entry *) bh->b_data; |
| 116 | /* Determine whether or not we have an index block */ |
| 117 | if (is_dx(inode)) { |
| 118 | if (block == 0) |
| 119 | is_dx_block = 1; |
| 120 | else if (ext4_rec_len_from_disk(dirent->rec_len, |
| 121 | inode->i_sb->s_blocksize) == |
| 122 | inode->i_sb->s_blocksize) |
| 123 | is_dx_block = 1; |
| 124 | } |
| 125 | if (!is_dx_block && type == INDEX) { |
| 126 | ext4_error_inode(inode, func, line, block, |
| 127 | "directory leaf block found instead of index block"); |
| 128 | brelse(bh); |
| 129 | return ERR_PTR(-EFSCORRUPTED); |
| 130 | } |
| 131 | if (!ext4_has_metadata_csum(inode->i_sb) || |
| 132 | buffer_verified(bh)) |
| 133 | return bh; |
| 134 | |
| 135 | /* |
| 136 | * An empty leaf block can get mistaken for a index block; for |
| 137 | * this reason, we can only check the index checksum when the |
| 138 | * caller is sure it should be an index block. |
| 139 | */ |
| 140 | if (is_dx_block && type == INDEX) { |
| 141 | if (ext4_dx_csum_verify(inode, dirent)) |
| 142 | set_buffer_verified(bh); |
| 143 | else { |
| 144 | ext4_error_inode(inode, func, line, block, |
| 145 | "Directory index failed checksum"); |
| 146 | brelse(bh); |
| 147 | return ERR_PTR(-EFSBADCRC); |
| 148 | } |
| 149 | } |
| 150 | if (!is_dx_block) { |
| 151 | if (ext4_dirent_csum_verify(inode, dirent)) |
| 152 | set_buffer_verified(bh); |
| 153 | else { |
| 154 | ext4_error_inode(inode, func, line, block, |
| 155 | "Directory block failed checksum"); |
| 156 | brelse(bh); |
| 157 | return ERR_PTR(-EFSBADCRC); |
| 158 | } |
| 159 | } |
| 160 | return bh; |
| 161 | } |
| 162 | |
| 163 | #ifndef assert |
| 164 | #define assert(test) J_ASSERT(test) |
| 165 | #endif |
| 166 | |
| 167 | #ifdef DX_DEBUG |
| 168 | #define dxtrace(command) command |
| 169 | #else |
| 170 | #define dxtrace(command) |
| 171 | #endif |
| 172 | |
| 173 | struct fake_dirent |
| 174 | { |
| 175 | __le32 inode; |
| 176 | __le16 rec_len; |
| 177 | u8 name_len; |
| 178 | u8 file_type; |
| 179 | }; |
| 180 | |
| 181 | struct dx_countlimit |
| 182 | { |
| 183 | __le16 limit; |
| 184 | __le16 count; |
| 185 | }; |
| 186 | |
| 187 | struct dx_entry |
| 188 | { |
| 189 | __le32 hash; |
| 190 | __le32 block; |
| 191 | }; |
| 192 | |
| 193 | /* |
| 194 | * dx_root_info is laid out so that if it should somehow get overlaid by a |
| 195 | * dirent the two low bits of the hash version will be zero. Therefore, the |
| 196 | * hash version mod 4 should never be 0. Sincerely, the paranoia department. |
| 197 | */ |
| 198 | |
| 199 | struct dx_root |
| 200 | { |
| 201 | struct fake_dirent dot; |
| 202 | char dot_name[4]; |
| 203 | struct fake_dirent dotdot; |
| 204 | char dotdot_name[4]; |
| 205 | struct dx_root_info |
| 206 | { |
| 207 | __le32 reserved_zero; |
| 208 | u8 hash_version; |
| 209 | u8 info_length; /* 8 */ |
| 210 | u8 indirect_levels; |
| 211 | u8 unused_flags; |
| 212 | } |
| 213 | info; |
| 214 | struct dx_entry entries[0]; |
| 215 | }; |
| 216 | |
| 217 | struct dx_node |
| 218 | { |
| 219 | struct fake_dirent fake; |
| 220 | struct dx_entry entries[0]; |
| 221 | }; |
| 222 | |
| 223 | |
| 224 | struct dx_frame |
| 225 | { |
| 226 | struct buffer_head *bh; |
| 227 | struct dx_entry *entries; |
| 228 | struct dx_entry *at; |
| 229 | }; |
| 230 | |
| 231 | struct dx_map_entry |
| 232 | { |
| 233 | u32 hash; |
| 234 | u16 offs; |
| 235 | u16 size; |
| 236 | }; |
| 237 | |
| 238 | /* |
| 239 | * This goes at the end of each htree block. |
| 240 | */ |
| 241 | struct dx_tail { |
| 242 | u32 dt_reserved; |
| 243 | __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */ |
| 244 | }; |
| 245 | |
| 246 | static inline ext4_lblk_t dx_get_block(struct dx_entry *entry); |
| 247 | static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value); |
| 248 | static inline unsigned dx_get_hash(struct dx_entry *entry); |
| 249 | static void dx_set_hash(struct dx_entry *entry, unsigned value); |
| 250 | static unsigned dx_get_count(struct dx_entry *entries); |
| 251 | static unsigned dx_get_limit(struct dx_entry *entries); |
| 252 | static void dx_set_count(struct dx_entry *entries, unsigned value); |
| 253 | static void dx_set_limit(struct dx_entry *entries, unsigned value); |
| 254 | static unsigned dx_root_limit(struct inode *dir, unsigned infosize); |
| 255 | static unsigned dx_node_limit(struct inode *dir); |
| 256 | static struct dx_frame *dx_probe(struct ext4_filename *fname, |
| 257 | struct inode *dir, |
| 258 | struct dx_hash_info *hinfo, |
| 259 | struct dx_frame *frame); |
| 260 | static void dx_release(struct dx_frame *frames); |
| 261 | static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de, |
| 262 | unsigned blocksize, struct dx_hash_info *hinfo, |
| 263 | struct dx_map_entry map[]); |
| 264 | static void dx_sort_map(struct dx_map_entry *map, unsigned count); |
| 265 | static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to, |
| 266 | struct dx_map_entry *offsets, int count, unsigned blocksize); |
| 267 | static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize); |
| 268 | static void dx_insert_block(struct dx_frame *frame, |
| 269 | u32 hash, ext4_lblk_t block); |
| 270 | static int ext4_htree_next_block(struct inode *dir, __u32 hash, |
| 271 | struct dx_frame *frame, |
| 272 | struct dx_frame *frames, |
| 273 | __u32 *start_hash); |
| 274 | static struct buffer_head * ext4_dx_find_entry(struct inode *dir, |
| 275 | struct ext4_filename *fname, |
| 276 | struct ext4_dir_entry_2 **res_dir); |
| 277 | static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname, |
| 278 | struct inode *dir, struct inode *inode); |
| 279 | |
| 280 | /* checksumming functions */ |
| 281 | void initialize_dirent_tail(struct ext4_dir_entry_tail *t, |
| 282 | unsigned int blocksize) |
| 283 | { |
| 284 | memset(t, 0, sizeof(struct ext4_dir_entry_tail)); |
| 285 | t->det_rec_len = ext4_rec_len_to_disk( |
| 286 | sizeof(struct ext4_dir_entry_tail), blocksize); |
| 287 | t->det_reserved_ft = EXT4_FT_DIR_CSUM; |
| 288 | } |
| 289 | |
| 290 | /* Walk through a dirent block to find a checksum "dirent" at the tail */ |
| 291 | static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode, |
| 292 | struct ext4_dir_entry *de) |
| 293 | { |
| 294 | struct ext4_dir_entry_tail *t; |
| 295 | |
| 296 | #ifdef PARANOID |
| 297 | struct ext4_dir_entry *d, *top; |
| 298 | |
| 299 | d = de; |
| 300 | top = (struct ext4_dir_entry *)(((void *)de) + |
| 301 | (EXT4_BLOCK_SIZE(inode->i_sb) - |
| 302 | sizeof(struct ext4_dir_entry_tail))); |
| 303 | while (d < top && d->rec_len) |
| 304 | d = (struct ext4_dir_entry *)(((void *)d) + |
| 305 | le16_to_cpu(d->rec_len)); |
| 306 | |
| 307 | if (d != top) |
| 308 | return NULL; |
| 309 | |
| 310 | t = (struct ext4_dir_entry_tail *)d; |
| 311 | #else |
| 312 | t = EXT4_DIRENT_TAIL(de, EXT4_BLOCK_SIZE(inode->i_sb)); |
| 313 | #endif |
| 314 | |
| 315 | if (t->det_reserved_zero1 || |
| 316 | le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) || |
| 317 | t->det_reserved_zero2 || |
| 318 | t->det_reserved_ft != EXT4_FT_DIR_CSUM) |
| 319 | return NULL; |
| 320 | |
| 321 | return t; |
| 322 | } |
| 323 | |
| 324 | static __le32 ext4_dirent_csum(struct inode *inode, |
| 325 | struct ext4_dir_entry *dirent, int size) |
| 326 | { |
| 327 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| 328 | struct ext4_inode_info *ei = EXT4_I(inode); |
| 329 | __u32 csum; |
| 330 | |
| 331 | csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size); |
| 332 | return cpu_to_le32(csum); |
| 333 | } |
| 334 | |
| 335 | #define warn_no_space_for_csum(inode) \ |
| 336 | __warn_no_space_for_csum((inode), __func__, __LINE__) |
| 337 | |
| 338 | static void __warn_no_space_for_csum(struct inode *inode, const char *func, |
| 339 | unsigned int line) |
| 340 | { |
| 341 | __ext4_warning_inode(inode, func, line, |
| 342 | "No space for directory leaf checksum. Please run e2fsck -D."); |
| 343 | } |
| 344 | |
| 345 | int ext4_dirent_csum_verify(struct inode *inode, struct ext4_dir_entry *dirent) |
| 346 | { |
| 347 | struct ext4_dir_entry_tail *t; |
| 348 | |
| 349 | if (!ext4_has_metadata_csum(inode->i_sb)) |
| 350 | return 1; |
| 351 | |
| 352 | t = get_dirent_tail(inode, dirent); |
| 353 | if (!t) { |
| 354 | warn_no_space_for_csum(inode); |
| 355 | return 0; |
| 356 | } |
| 357 | |
| 358 | if (t->det_checksum != ext4_dirent_csum(inode, dirent, |
| 359 | (void *)t - (void *)dirent)) |
| 360 | return 0; |
| 361 | |
| 362 | return 1; |
| 363 | } |
| 364 | |
| 365 | static void ext4_dirent_csum_set(struct inode *inode, |
| 366 | struct ext4_dir_entry *dirent) |
| 367 | { |
| 368 | struct ext4_dir_entry_tail *t; |
| 369 | |
| 370 | if (!ext4_has_metadata_csum(inode->i_sb)) |
| 371 | return; |
| 372 | |
| 373 | t = get_dirent_tail(inode, dirent); |
| 374 | if (!t) { |
| 375 | warn_no_space_for_csum(inode); |
| 376 | return; |
| 377 | } |
| 378 | |
| 379 | t->det_checksum = ext4_dirent_csum(inode, dirent, |
| 380 | (void *)t - (void *)dirent); |
| 381 | } |
| 382 | |
| 383 | int ext4_handle_dirty_dirent_node(handle_t *handle, |
| 384 | struct inode *inode, |
| 385 | struct buffer_head *bh) |
| 386 | { |
| 387 | ext4_dirent_csum_set(inode, (struct ext4_dir_entry *)bh->b_data); |
| 388 | return ext4_handle_dirty_metadata(handle, inode, bh); |
| 389 | } |
| 390 | |
| 391 | static struct dx_countlimit *get_dx_countlimit(struct inode *inode, |
| 392 | struct ext4_dir_entry *dirent, |
| 393 | int *offset) |
| 394 | { |
| 395 | struct ext4_dir_entry *dp; |
| 396 | struct dx_root_info *root; |
| 397 | int count_offset; |
| 398 | |
| 399 | if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb)) |
| 400 | count_offset = 8; |
| 401 | else if (le16_to_cpu(dirent->rec_len) == 12) { |
| 402 | dp = (struct ext4_dir_entry *)(((void *)dirent) + 12); |
| 403 | if (le16_to_cpu(dp->rec_len) != |
| 404 | EXT4_BLOCK_SIZE(inode->i_sb) - 12) |
| 405 | return NULL; |
| 406 | root = (struct dx_root_info *)(((void *)dp + 12)); |
| 407 | if (root->reserved_zero || |
| 408 | root->info_length != sizeof(struct dx_root_info)) |
| 409 | return NULL; |
| 410 | count_offset = 32; |
| 411 | } else |
| 412 | return NULL; |
| 413 | |
| 414 | if (offset) |
| 415 | *offset = count_offset; |
| 416 | return (struct dx_countlimit *)(((void *)dirent) + count_offset); |
| 417 | } |
| 418 | |
| 419 | static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent, |
| 420 | int count_offset, int count, struct dx_tail *t) |
| 421 | { |
| 422 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| 423 | struct ext4_inode_info *ei = EXT4_I(inode); |
| 424 | __u32 csum; |
| 425 | int size; |
| 426 | __u32 dummy_csum = 0; |
| 427 | int offset = offsetof(struct dx_tail, dt_checksum); |
| 428 | |
| 429 | size = count_offset + (count * sizeof(struct dx_entry)); |
| 430 | csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size); |
| 431 | csum = ext4_chksum(sbi, csum, (__u8 *)t, offset); |
| 432 | csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum)); |
| 433 | |
| 434 | return cpu_to_le32(csum); |
| 435 | } |
| 436 | |
| 437 | static int ext4_dx_csum_verify(struct inode *inode, |
| 438 | struct ext4_dir_entry *dirent) |
| 439 | { |
| 440 | struct dx_countlimit *c; |
| 441 | struct dx_tail *t; |
| 442 | int count_offset, limit, count; |
| 443 | |
| 444 | if (!ext4_has_metadata_csum(inode->i_sb)) |
| 445 | return 1; |
| 446 | |
| 447 | c = get_dx_countlimit(inode, dirent, &count_offset); |
| 448 | if (!c) { |
| 449 | EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D."); |
| 450 | return 0; |
| 451 | } |
| 452 | limit = le16_to_cpu(c->limit); |
| 453 | count = le16_to_cpu(c->count); |
| 454 | if (count_offset + (limit * sizeof(struct dx_entry)) > |
| 455 | EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) { |
| 456 | warn_no_space_for_csum(inode); |
| 457 | return 0; |
| 458 | } |
| 459 | t = (struct dx_tail *)(((struct dx_entry *)c) + limit); |
| 460 | |
| 461 | if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset, |
| 462 | count, t)) |
| 463 | return 0; |
| 464 | return 1; |
| 465 | } |
| 466 | |
| 467 | static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent) |
| 468 | { |
| 469 | struct dx_countlimit *c; |
| 470 | struct dx_tail *t; |
| 471 | int count_offset, limit, count; |
| 472 | |
| 473 | if (!ext4_has_metadata_csum(inode->i_sb)) |
| 474 | return; |
| 475 | |
| 476 | c = get_dx_countlimit(inode, dirent, &count_offset); |
| 477 | if (!c) { |
| 478 | EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D."); |
| 479 | return; |
| 480 | } |
| 481 | limit = le16_to_cpu(c->limit); |
| 482 | count = le16_to_cpu(c->count); |
| 483 | if (count_offset + (limit * sizeof(struct dx_entry)) > |
| 484 | EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) { |
| 485 | warn_no_space_for_csum(inode); |
| 486 | return; |
| 487 | } |
| 488 | t = (struct dx_tail *)(((struct dx_entry *)c) + limit); |
| 489 | |
| 490 | t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t); |
| 491 | } |
| 492 | |
| 493 | static inline int ext4_handle_dirty_dx_node(handle_t *handle, |
| 494 | struct inode *inode, |
| 495 | struct buffer_head *bh) |
| 496 | { |
| 497 | ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data); |
| 498 | return ext4_handle_dirty_metadata(handle, inode, bh); |
| 499 | } |
| 500 | |
| 501 | /* |
| 502 | * p is at least 6 bytes before the end of page |
| 503 | */ |
| 504 | static inline struct ext4_dir_entry_2 * |
| 505 | ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize) |
| 506 | { |
| 507 | return (struct ext4_dir_entry_2 *)((char *)p + |
| 508 | ext4_rec_len_from_disk(p->rec_len, blocksize)); |
| 509 | } |
| 510 | |
| 511 | /* |
| 512 | * Future: use high four bits of block for coalesce-on-delete flags |
| 513 | * Mask them off for now. |
| 514 | */ |
| 515 | |
| 516 | static inline ext4_lblk_t dx_get_block(struct dx_entry *entry) |
| 517 | { |
| 518 | return le32_to_cpu(entry->block) & 0x0fffffff; |
| 519 | } |
| 520 | |
| 521 | static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value) |
| 522 | { |
| 523 | entry->block = cpu_to_le32(value); |
| 524 | } |
| 525 | |
| 526 | static inline unsigned dx_get_hash(struct dx_entry *entry) |
| 527 | { |
| 528 | return le32_to_cpu(entry->hash); |
| 529 | } |
| 530 | |
| 531 | static inline void dx_set_hash(struct dx_entry *entry, unsigned value) |
| 532 | { |
| 533 | entry->hash = cpu_to_le32(value); |
| 534 | } |
| 535 | |
| 536 | static inline unsigned dx_get_count(struct dx_entry *entries) |
| 537 | { |
| 538 | return le16_to_cpu(((struct dx_countlimit *) entries)->count); |
| 539 | } |
| 540 | |
| 541 | static inline unsigned dx_get_limit(struct dx_entry *entries) |
| 542 | { |
| 543 | return le16_to_cpu(((struct dx_countlimit *) entries)->limit); |
| 544 | } |
| 545 | |
| 546 | static inline void dx_set_count(struct dx_entry *entries, unsigned value) |
| 547 | { |
| 548 | ((struct dx_countlimit *) entries)->count = cpu_to_le16(value); |
| 549 | } |
| 550 | |
| 551 | static inline void dx_set_limit(struct dx_entry *entries, unsigned value) |
| 552 | { |
| 553 | ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value); |
| 554 | } |
| 555 | |
| 556 | static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize) |
| 557 | { |
| 558 | unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) - |
| 559 | EXT4_DIR_REC_LEN(2) - infosize; |
| 560 | |
| 561 | if (ext4_has_metadata_csum(dir->i_sb)) |
| 562 | entry_space -= sizeof(struct dx_tail); |
| 563 | return entry_space / sizeof(struct dx_entry); |
| 564 | } |
| 565 | |
| 566 | static inline unsigned dx_node_limit(struct inode *dir) |
| 567 | { |
| 568 | unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0); |
| 569 | |
| 570 | if (ext4_has_metadata_csum(dir->i_sb)) |
| 571 | entry_space -= sizeof(struct dx_tail); |
| 572 | return entry_space / sizeof(struct dx_entry); |
| 573 | } |
| 574 | |
| 575 | /* |
| 576 | * Debug |
| 577 | */ |
| 578 | #ifdef DX_DEBUG |
| 579 | static void dx_show_index(char * label, struct dx_entry *entries) |
| 580 | { |
| 581 | int i, n = dx_get_count (entries); |
| 582 | printk(KERN_DEBUG "%s index", label); |
| 583 | for (i = 0; i < n; i++) { |
| 584 | printk(KERN_CONT " %x->%lu", |
| 585 | i ? dx_get_hash(entries + i) : 0, |
| 586 | (unsigned long)dx_get_block(entries + i)); |
| 587 | } |
| 588 | printk(KERN_CONT "\n"); |
| 589 | } |
| 590 | |
| 591 | struct stats |
| 592 | { |
| 593 | unsigned names; |
| 594 | unsigned space; |
| 595 | unsigned bcount; |
| 596 | }; |
| 597 | |
| 598 | static struct stats dx_show_leaf(struct inode *dir, |
| 599 | struct dx_hash_info *hinfo, |
| 600 | struct ext4_dir_entry_2 *de, |
| 601 | int size, int show_names) |
| 602 | { |
| 603 | unsigned names = 0, space = 0; |
| 604 | char *base = (char *) de; |
| 605 | struct dx_hash_info h = *hinfo; |
| 606 | |
| 607 | printk("names: "); |
| 608 | while ((char *) de < base + size) |
| 609 | { |
| 610 | if (de->inode) |
| 611 | { |
| 612 | if (show_names) |
| 613 | { |
| 614 | #ifdef CONFIG_EXT4_FS_ENCRYPTION |
| 615 | int len; |
| 616 | char *name; |
| 617 | struct fscrypt_str fname_crypto_str = |
| 618 | FSTR_INIT(NULL, 0); |
| 619 | int res = 0; |
| 620 | |
| 621 | name = de->name; |
| 622 | len = de->name_len; |
| 623 | if (ext4_encrypted_inode(dir)) |
| 624 | res = fscrypt_get_encryption_info(dir); |
| 625 | if (res) { |
| 626 | printk(KERN_WARNING "Error setting up" |
| 627 | " fname crypto: %d\n", res); |
| 628 | } |
| 629 | if (!fscrypt_has_encryption_key(dir)) { |
| 630 | /* Directory is not encrypted */ |
| 631 | ext4fs_dirhash(de->name, |
| 632 | de->name_len, &h); |
| 633 | printk("%*.s:(U)%x.%u ", len, |
| 634 | name, h.hash, |
| 635 | (unsigned) ((char *) de |
| 636 | - base)); |
| 637 | } else { |
| 638 | struct fscrypt_str de_name = |
| 639 | FSTR_INIT(name, len); |
| 640 | |
| 641 | /* Directory is encrypted */ |
| 642 | res = fscrypt_fname_alloc_buffer( |
| 643 | dir, len, |
| 644 | &fname_crypto_str); |
| 645 | if (res) |
| 646 | printk(KERN_WARNING "Error " |
| 647 | "allocating crypto " |
| 648 | "buffer--skipping " |
| 649 | "crypto\n"); |
| 650 | res = fscrypt_fname_disk_to_usr(dir, |
| 651 | 0, 0, &de_name, |
| 652 | &fname_crypto_str); |
| 653 | if (res) { |
| 654 | printk(KERN_WARNING "Error " |
| 655 | "converting filename " |
| 656 | "from disk to usr" |
| 657 | "\n"); |
| 658 | name = "??"; |
| 659 | len = 2; |
| 660 | } else { |
| 661 | name = fname_crypto_str.name; |
| 662 | len = fname_crypto_str.len; |
| 663 | } |
| 664 | ext4fs_dirhash(de->name, de->name_len, |
| 665 | &h); |
| 666 | printk("%*.s:(E)%x.%u ", len, name, |
| 667 | h.hash, (unsigned) ((char *) de |
| 668 | - base)); |
| 669 | fscrypt_fname_free_buffer( |
| 670 | &fname_crypto_str); |
| 671 | } |
| 672 | #else |
| 673 | int len = de->name_len; |
| 674 | char *name = de->name; |
| 675 | ext4fs_dirhash(de->name, de->name_len, &h); |
| 676 | printk("%*.s:%x.%u ", len, name, h.hash, |
| 677 | (unsigned) ((char *) de - base)); |
| 678 | #endif |
| 679 | } |
| 680 | space += EXT4_DIR_REC_LEN(de->name_len); |
| 681 | names++; |
| 682 | } |
| 683 | de = ext4_next_entry(de, size); |
| 684 | } |
| 685 | printk(KERN_CONT "(%i)\n", names); |
| 686 | return (struct stats) { names, space, 1 }; |
| 687 | } |
| 688 | |
| 689 | struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir, |
| 690 | struct dx_entry *entries, int levels) |
| 691 | { |
| 692 | unsigned blocksize = dir->i_sb->s_blocksize; |
| 693 | unsigned count = dx_get_count(entries), names = 0, space = 0, i; |
| 694 | unsigned bcount = 0; |
| 695 | struct buffer_head *bh; |
| 696 | printk("%i indexed blocks...\n", count); |
| 697 | for (i = 0; i < count; i++, entries++) |
| 698 | { |
| 699 | ext4_lblk_t block = dx_get_block(entries); |
| 700 | ext4_lblk_t hash = i ? dx_get_hash(entries): 0; |
| 701 | u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash; |
| 702 | struct stats stats; |
| 703 | printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range); |
| 704 | bh = ext4_bread(NULL,dir, block, 0); |
| 705 | if (!bh || IS_ERR(bh)) |
| 706 | continue; |
| 707 | stats = levels? |
| 708 | dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1): |
| 709 | dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) |
| 710 | bh->b_data, blocksize, 0); |
| 711 | names += stats.names; |
| 712 | space += stats.space; |
| 713 | bcount += stats.bcount; |
| 714 | brelse(bh); |
| 715 | } |
| 716 | if (bcount) |
| 717 | printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n", |
| 718 | levels ? "" : " ", names, space/bcount, |
| 719 | (space/bcount)*100/blocksize); |
| 720 | return (struct stats) { names, space, bcount}; |
| 721 | } |
| 722 | #endif /* DX_DEBUG */ |
| 723 | |
| 724 | /* |
| 725 | * Probe for a directory leaf block to search. |
| 726 | * |
| 727 | * dx_probe can return ERR_BAD_DX_DIR, which means there was a format |
| 728 | * error in the directory index, and the caller should fall back to |
| 729 | * searching the directory normally. The callers of dx_probe **MUST** |
| 730 | * check for this error code, and make sure it never gets reflected |
| 731 | * back to userspace. |
| 732 | */ |
| 733 | static struct dx_frame * |
| 734 | dx_probe(struct ext4_filename *fname, struct inode *dir, |
| 735 | struct dx_hash_info *hinfo, struct dx_frame *frame_in) |
| 736 | { |
| 737 | unsigned count, indirect; |
| 738 | struct dx_entry *at, *entries, *p, *q, *m; |
| 739 | struct dx_root *root; |
| 740 | struct dx_frame *frame = frame_in; |
| 741 | struct dx_frame *ret_err = ERR_PTR(ERR_BAD_DX_DIR); |
| 742 | u32 hash; |
| 743 | |
| 744 | memset(frame_in, 0, EXT4_HTREE_LEVEL * sizeof(frame_in[0])); |
| 745 | frame->bh = ext4_read_dirblock(dir, 0, INDEX); |
| 746 | if (IS_ERR(frame->bh)) |
| 747 | return (struct dx_frame *) frame->bh; |
| 748 | |
| 749 | root = (struct dx_root *) frame->bh->b_data; |
| 750 | if (root->info.hash_version != DX_HASH_TEA && |
| 751 | root->info.hash_version != DX_HASH_HALF_MD4 && |
| 752 | root->info.hash_version != DX_HASH_LEGACY) { |
| 753 | ext4_warning_inode(dir, "Unrecognised inode hash code %u", |
| 754 | root->info.hash_version); |
| 755 | goto fail; |
| 756 | } |
| 757 | if (fname) |
| 758 | hinfo = &fname->hinfo; |
| 759 | hinfo->hash_version = root->info.hash_version; |
| 760 | if (hinfo->hash_version <= DX_HASH_TEA) |
| 761 | hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; |
| 762 | hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed; |
| 763 | if (fname && fname_name(fname)) |
| 764 | ext4fs_dirhash(fname_name(fname), fname_len(fname), hinfo); |
| 765 | hash = hinfo->hash; |
| 766 | |
| 767 | if (root->info.unused_flags & 1) { |
| 768 | ext4_warning_inode(dir, "Unimplemented hash flags: %#06x", |
| 769 | root->info.unused_flags); |
| 770 | goto fail; |
| 771 | } |
| 772 | |
| 773 | indirect = root->info.indirect_levels; |
| 774 | if (indirect >= ext4_dir_htree_level(dir->i_sb)) { |
| 775 | ext4_warning(dir->i_sb, |
| 776 | "Directory (ino: %lu) htree depth %#06x exceed" |
| 777 | "supported value", dir->i_ino, |
| 778 | ext4_dir_htree_level(dir->i_sb)); |
| 779 | if (ext4_dir_htree_level(dir->i_sb) < EXT4_HTREE_LEVEL) { |
| 780 | ext4_warning(dir->i_sb, "Enable large directory " |
| 781 | "feature to access it"); |
| 782 | } |
| 783 | goto fail; |
| 784 | } |
| 785 | |
| 786 | entries = (struct dx_entry *)(((char *)&root->info) + |
| 787 | root->info.info_length); |
| 788 | |
| 789 | if (dx_get_limit(entries) != dx_root_limit(dir, |
| 790 | root->info.info_length)) { |
| 791 | ext4_warning_inode(dir, "dx entry: limit %u != root limit %u", |
| 792 | dx_get_limit(entries), |
| 793 | dx_root_limit(dir, root->info.info_length)); |
| 794 | goto fail; |
| 795 | } |
| 796 | |
| 797 | dxtrace(printk("Look up %x", hash)); |
| 798 | while (1) { |
| 799 | count = dx_get_count(entries); |
| 800 | if (!count || count > dx_get_limit(entries)) { |
| 801 | ext4_warning_inode(dir, |
| 802 | "dx entry: count %u beyond limit %u", |
| 803 | count, dx_get_limit(entries)); |
| 804 | goto fail; |
| 805 | } |
| 806 | |
| 807 | p = entries + 1; |
| 808 | q = entries + count - 1; |
| 809 | while (p <= q) { |
| 810 | m = p + (q - p) / 2; |
| 811 | dxtrace(printk(KERN_CONT ".")); |
| 812 | if (dx_get_hash(m) > hash) |
| 813 | q = m - 1; |
| 814 | else |
| 815 | p = m + 1; |
| 816 | } |
| 817 | |
| 818 | if (0) { // linear search cross check |
| 819 | unsigned n = count - 1; |
| 820 | at = entries; |
| 821 | while (n--) |
| 822 | { |
| 823 | dxtrace(printk(KERN_CONT ",")); |
| 824 | if (dx_get_hash(++at) > hash) |
| 825 | { |
| 826 | at--; |
| 827 | break; |
| 828 | } |
| 829 | } |
| 830 | assert (at == p - 1); |
| 831 | } |
| 832 | |
| 833 | at = p - 1; |
| 834 | dxtrace(printk(KERN_CONT " %x->%u\n", |
| 835 | at == entries ? 0 : dx_get_hash(at), |
| 836 | dx_get_block(at))); |
| 837 | frame->entries = entries; |
| 838 | frame->at = at; |
| 839 | if (!indirect--) |
| 840 | return frame; |
| 841 | frame++; |
| 842 | frame->bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX); |
| 843 | if (IS_ERR(frame->bh)) { |
| 844 | ret_err = (struct dx_frame *) frame->bh; |
| 845 | frame->bh = NULL; |
| 846 | goto fail; |
| 847 | } |
| 848 | entries = ((struct dx_node *) frame->bh->b_data)->entries; |
| 849 | |
| 850 | if (dx_get_limit(entries) != dx_node_limit(dir)) { |
| 851 | ext4_warning_inode(dir, |
| 852 | "dx entry: limit %u != node limit %u", |
| 853 | dx_get_limit(entries), dx_node_limit(dir)); |
| 854 | goto fail; |
| 855 | } |
| 856 | } |
| 857 | fail: |
| 858 | while (frame >= frame_in) { |
| 859 | brelse(frame->bh); |
| 860 | frame--; |
| 861 | } |
| 862 | |
| 863 | if (ret_err == ERR_PTR(ERR_BAD_DX_DIR)) |
| 864 | ext4_warning_inode(dir, |
| 865 | "Corrupt directory, running e2fsck is recommended"); |
| 866 | return ret_err; |
| 867 | } |
| 868 | |
| 869 | static void dx_release(struct dx_frame *frames) |
| 870 | { |
| 871 | struct dx_root_info *info; |
| 872 | int i; |
| 873 | |
| 874 | if (frames[0].bh == NULL) |
| 875 | return; |
| 876 | |
| 877 | info = &((struct dx_root *)frames[0].bh->b_data)->info; |
| 878 | for (i = 0; i <= info->indirect_levels; i++) { |
| 879 | if (frames[i].bh == NULL) |
| 880 | break; |
| 881 | brelse(frames[i].bh); |
| 882 | frames[i].bh = NULL; |
| 883 | } |
| 884 | } |
| 885 | |
| 886 | /* |
| 887 | * This function increments the frame pointer to search the next leaf |
| 888 | * block, and reads in the necessary intervening nodes if the search |
| 889 | * should be necessary. Whether or not the search is necessary is |
| 890 | * controlled by the hash parameter. If the hash value is even, then |
| 891 | * the search is only continued if the next block starts with that |
| 892 | * hash value. This is used if we are searching for a specific file. |
| 893 | * |
| 894 | * If the hash value is HASH_NB_ALWAYS, then always go to the next block. |
| 895 | * |
| 896 | * This function returns 1 if the caller should continue to search, |
| 897 | * or 0 if it should not. If there is an error reading one of the |
| 898 | * index blocks, it will a negative error code. |
| 899 | * |
| 900 | * If start_hash is non-null, it will be filled in with the starting |
| 901 | * hash of the next page. |
| 902 | */ |
| 903 | static int ext4_htree_next_block(struct inode *dir, __u32 hash, |
| 904 | struct dx_frame *frame, |
| 905 | struct dx_frame *frames, |
| 906 | __u32 *start_hash) |
| 907 | { |
| 908 | struct dx_frame *p; |
| 909 | struct buffer_head *bh; |
| 910 | int num_frames = 0; |
| 911 | __u32 bhash; |
| 912 | |
| 913 | p = frame; |
| 914 | /* |
| 915 | * Find the next leaf page by incrementing the frame pointer. |
| 916 | * If we run out of entries in the interior node, loop around and |
| 917 | * increment pointer in the parent node. When we break out of |
| 918 | * this loop, num_frames indicates the number of interior |
| 919 | * nodes need to be read. |
| 920 | */ |
| 921 | while (1) { |
| 922 | if (++(p->at) < p->entries + dx_get_count(p->entries)) |
| 923 | break; |
| 924 | if (p == frames) |
| 925 | return 0; |
| 926 | num_frames++; |
| 927 | p--; |
| 928 | } |
| 929 | |
| 930 | /* |
| 931 | * If the hash is 1, then continue only if the next page has a |
| 932 | * continuation hash of any value. This is used for readdir |
| 933 | * handling. Otherwise, check to see if the hash matches the |
| 934 | * desired contiuation hash. If it doesn't, return since |
| 935 | * there's no point to read in the successive index pages. |
| 936 | */ |
| 937 | bhash = dx_get_hash(p->at); |
| 938 | if (start_hash) |
| 939 | *start_hash = bhash; |
| 940 | if ((hash & 1) == 0) { |
| 941 | if ((bhash & ~1) != hash) |
| 942 | return 0; |
| 943 | } |
| 944 | /* |
| 945 | * If the hash is HASH_NB_ALWAYS, we always go to the next |
| 946 | * block so no check is necessary |
| 947 | */ |
| 948 | while (num_frames--) { |
| 949 | bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX); |
| 950 | if (IS_ERR(bh)) |
| 951 | return PTR_ERR(bh); |
| 952 | p++; |
| 953 | brelse(p->bh); |
| 954 | p->bh = bh; |
| 955 | p->at = p->entries = ((struct dx_node *) bh->b_data)->entries; |
| 956 | } |
| 957 | return 1; |
| 958 | } |
| 959 | |
| 960 | |
| 961 | /* |
| 962 | * This function fills a red-black tree with information from a |
| 963 | * directory block. It returns the number directory entries loaded |
| 964 | * into the tree. If there is an error it is returned in err. |
| 965 | */ |
| 966 | static int htree_dirblock_to_tree(struct file *dir_file, |
| 967 | struct inode *dir, ext4_lblk_t block, |
| 968 | struct dx_hash_info *hinfo, |
| 969 | __u32 start_hash, __u32 start_minor_hash) |
| 970 | { |
| 971 | struct buffer_head *bh; |
| 972 | struct ext4_dir_entry_2 *de, *top; |
| 973 | int err = 0, count = 0; |
| 974 | struct fscrypt_str fname_crypto_str = FSTR_INIT(NULL, 0), tmp_str; |
| 975 | |
| 976 | dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n", |
| 977 | (unsigned long)block)); |
| 978 | bh = ext4_read_dirblock(dir, block, DIRENT); |
| 979 | if (IS_ERR(bh)) |
| 980 | return PTR_ERR(bh); |
| 981 | |
| 982 | de = (struct ext4_dir_entry_2 *) bh->b_data; |
| 983 | top = (struct ext4_dir_entry_2 *) ((char *) de + |
| 984 | dir->i_sb->s_blocksize - |
| 985 | EXT4_DIR_REC_LEN(0)); |
| 986 | #ifdef CONFIG_EXT4_FS_ENCRYPTION |
| 987 | /* Check if the directory is encrypted */ |
| 988 | if (ext4_encrypted_inode(dir)) { |
| 989 | err = fscrypt_get_encryption_info(dir); |
| 990 | if (err < 0) { |
| 991 | brelse(bh); |
| 992 | return err; |
| 993 | } |
| 994 | err = fscrypt_fname_alloc_buffer(dir, EXT4_NAME_LEN, |
| 995 | &fname_crypto_str); |
| 996 | if (err < 0) { |
| 997 | brelse(bh); |
| 998 | return err; |
| 999 | } |
| 1000 | } |
| 1001 | #endif |
| 1002 | for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) { |
| 1003 | if (ext4_check_dir_entry(dir, NULL, de, bh, |
| 1004 | bh->b_data, bh->b_size, |
| 1005 | (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb)) |
| 1006 | + ((char *)de - bh->b_data))) { |
| 1007 | /* silently ignore the rest of the block */ |
| 1008 | break; |
| 1009 | } |
| 1010 | ext4fs_dirhash(de->name, de->name_len, hinfo); |
| 1011 | if ((hinfo->hash < start_hash) || |
| 1012 | ((hinfo->hash == start_hash) && |
| 1013 | (hinfo->minor_hash < start_minor_hash))) |
| 1014 | continue; |
| 1015 | if (de->inode == 0) |
| 1016 | continue; |
| 1017 | if (!ext4_encrypted_inode(dir)) { |
| 1018 | tmp_str.name = de->name; |
| 1019 | tmp_str.len = de->name_len; |
| 1020 | err = ext4_htree_store_dirent(dir_file, |
| 1021 | hinfo->hash, hinfo->minor_hash, de, |
| 1022 | &tmp_str); |
| 1023 | } else { |
| 1024 | int save_len = fname_crypto_str.len; |
| 1025 | struct fscrypt_str de_name = FSTR_INIT(de->name, |
| 1026 | de->name_len); |
| 1027 | |
| 1028 | /* Directory is encrypted */ |
| 1029 | err = fscrypt_fname_disk_to_usr(dir, hinfo->hash, |
| 1030 | hinfo->minor_hash, &de_name, |
| 1031 | &fname_crypto_str); |
| 1032 | if (err) { |
| 1033 | count = err; |
| 1034 | goto errout; |
| 1035 | } |
| 1036 | err = ext4_htree_store_dirent(dir_file, |
| 1037 | hinfo->hash, hinfo->minor_hash, de, |
| 1038 | &fname_crypto_str); |
| 1039 | fname_crypto_str.len = save_len; |
| 1040 | } |
| 1041 | if (err != 0) { |
| 1042 | count = err; |
| 1043 | goto errout; |
| 1044 | } |
| 1045 | count++; |
| 1046 | } |
| 1047 | errout: |
| 1048 | brelse(bh); |
| 1049 | #ifdef CONFIG_EXT4_FS_ENCRYPTION |
| 1050 | fscrypt_fname_free_buffer(&fname_crypto_str); |
| 1051 | #endif |
| 1052 | return count; |
| 1053 | } |
| 1054 | |
| 1055 | |
| 1056 | /* |
| 1057 | * This function fills a red-black tree with information from a |
| 1058 | * directory. We start scanning the directory in hash order, starting |
| 1059 | * at start_hash and start_minor_hash. |
| 1060 | * |
| 1061 | * This function returns the number of entries inserted into the tree, |
| 1062 | * or a negative error code. |
| 1063 | */ |
| 1064 | int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash, |
| 1065 | __u32 start_minor_hash, __u32 *next_hash) |
| 1066 | { |
| 1067 | struct dx_hash_info hinfo; |
| 1068 | struct ext4_dir_entry_2 *de; |
| 1069 | struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; |
| 1070 | struct inode *dir; |
| 1071 | ext4_lblk_t block; |
| 1072 | int count = 0; |
| 1073 | int ret, err; |
| 1074 | __u32 hashval; |
| 1075 | struct fscrypt_str tmp_str; |
| 1076 | |
| 1077 | dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n", |
| 1078 | start_hash, start_minor_hash)); |
| 1079 | dir = file_inode(dir_file); |
| 1080 | if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) { |
| 1081 | hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; |
| 1082 | if (hinfo.hash_version <= DX_HASH_TEA) |
| 1083 | hinfo.hash_version += |
| 1084 | EXT4_SB(dir->i_sb)->s_hash_unsigned; |
| 1085 | hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; |
| 1086 | if (ext4_has_inline_data(dir)) { |
| 1087 | int has_inline_data = 1; |
| 1088 | count = htree_inlinedir_to_tree(dir_file, dir, 0, |
| 1089 | &hinfo, start_hash, |
| 1090 | start_minor_hash, |
| 1091 | &has_inline_data); |
| 1092 | if (has_inline_data) { |
| 1093 | *next_hash = ~0; |
| 1094 | return count; |
| 1095 | } |
| 1096 | } |
| 1097 | count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo, |
| 1098 | start_hash, start_minor_hash); |
| 1099 | *next_hash = ~0; |
| 1100 | return count; |
| 1101 | } |
| 1102 | hinfo.hash = start_hash; |
| 1103 | hinfo.minor_hash = 0; |
| 1104 | frame = dx_probe(NULL, dir, &hinfo, frames); |
| 1105 | if (IS_ERR(frame)) |
| 1106 | return PTR_ERR(frame); |
| 1107 | |
| 1108 | /* Add '.' and '..' from the htree header */ |
| 1109 | if (!start_hash && !start_minor_hash) { |
| 1110 | de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data; |
| 1111 | tmp_str.name = de->name; |
| 1112 | tmp_str.len = de->name_len; |
| 1113 | err = ext4_htree_store_dirent(dir_file, 0, 0, |
| 1114 | de, &tmp_str); |
| 1115 | if (err != 0) |
| 1116 | goto errout; |
| 1117 | count++; |
| 1118 | } |
| 1119 | if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) { |
| 1120 | de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data; |
| 1121 | de = ext4_next_entry(de, dir->i_sb->s_blocksize); |
| 1122 | tmp_str.name = de->name; |
| 1123 | tmp_str.len = de->name_len; |
| 1124 | err = ext4_htree_store_dirent(dir_file, 2, 0, |
| 1125 | de, &tmp_str); |
| 1126 | if (err != 0) |
| 1127 | goto errout; |
| 1128 | count++; |
| 1129 | } |
| 1130 | |
| 1131 | while (1) { |
| 1132 | if (fatal_signal_pending(current)) { |
| 1133 | err = -ERESTARTSYS; |
| 1134 | goto errout; |
| 1135 | } |
| 1136 | cond_resched(); |
| 1137 | block = dx_get_block(frame->at); |
| 1138 | ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo, |
| 1139 | start_hash, start_minor_hash); |
| 1140 | if (ret < 0) { |
| 1141 | err = ret; |
| 1142 | goto errout; |
| 1143 | } |
| 1144 | count += ret; |
| 1145 | hashval = ~0; |
| 1146 | ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS, |
| 1147 | frame, frames, &hashval); |
| 1148 | *next_hash = hashval; |
| 1149 | if (ret < 0) { |
| 1150 | err = ret; |
| 1151 | goto errout; |
| 1152 | } |
| 1153 | /* |
| 1154 | * Stop if: (a) there are no more entries, or |
| 1155 | * (b) we have inserted at least one entry and the |
| 1156 | * next hash value is not a continuation |
| 1157 | */ |
| 1158 | if ((ret == 0) || |
| 1159 | (count && ((hashval & 1) == 0))) |
| 1160 | break; |
| 1161 | } |
| 1162 | dx_release(frames); |
| 1163 | dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, " |
| 1164 | "next hash: %x\n", count, *next_hash)); |
| 1165 | return count; |
| 1166 | errout: |
| 1167 | dx_release(frames); |
| 1168 | return (err); |
| 1169 | } |
| 1170 | |
| 1171 | static inline int search_dirblock(struct buffer_head *bh, |
| 1172 | struct inode *dir, |
| 1173 | struct ext4_filename *fname, |
| 1174 | unsigned int offset, |
| 1175 | struct ext4_dir_entry_2 **res_dir) |
| 1176 | { |
| 1177 | return ext4_search_dir(bh, bh->b_data, dir->i_sb->s_blocksize, dir, |
| 1178 | fname, offset, res_dir); |
| 1179 | } |
| 1180 | |
| 1181 | /* |
| 1182 | * Directory block splitting, compacting |
| 1183 | */ |
| 1184 | |
| 1185 | /* |
| 1186 | * Create map of hash values, offsets, and sizes, stored at end of block. |
| 1187 | * Returns number of entries mapped. |
| 1188 | */ |
| 1189 | static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de, |
| 1190 | unsigned blocksize, struct dx_hash_info *hinfo, |
| 1191 | struct dx_map_entry *map_tail) |
| 1192 | { |
| 1193 | int count = 0; |
| 1194 | char *base = (char *) de; |
| 1195 | struct dx_hash_info h = *hinfo; |
| 1196 | |
| 1197 | while ((char *) de < base + blocksize) { |
| 1198 | if (de->name_len && de->inode) { |
| 1199 | ext4fs_dirhash(de->name, de->name_len, &h); |
| 1200 | map_tail--; |
| 1201 | map_tail->hash = h.hash; |
| 1202 | map_tail->offs = ((char *) de - base)>>2; |
| 1203 | map_tail->size = le16_to_cpu(de->rec_len); |
| 1204 | count++; |
| 1205 | cond_resched(); |
| 1206 | } |
| 1207 | /* XXX: do we need to check rec_len == 0 case? -Chris */ |
| 1208 | de = ext4_next_entry(de, blocksize); |
| 1209 | } |
| 1210 | return count; |
| 1211 | } |
| 1212 | |
| 1213 | /* Sort map by hash value */ |
| 1214 | static void dx_sort_map (struct dx_map_entry *map, unsigned count) |
| 1215 | { |
| 1216 | struct dx_map_entry *p, *q, *top = map + count - 1; |
| 1217 | int more; |
| 1218 | /* Combsort until bubble sort doesn't suck */ |
| 1219 | while (count > 2) { |
| 1220 | count = count*10/13; |
| 1221 | if (count - 9 < 2) /* 9, 10 -> 11 */ |
| 1222 | count = 11; |
| 1223 | for (p = top, q = p - count; q >= map; p--, q--) |
| 1224 | if (p->hash < q->hash) |
| 1225 | swap(*p, *q); |
| 1226 | } |
| 1227 | /* Garden variety bubble sort */ |
| 1228 | do { |
| 1229 | more = 0; |
| 1230 | q = top; |
| 1231 | while (q-- > map) { |
| 1232 | if (q[1].hash >= q[0].hash) |
| 1233 | continue; |
| 1234 | swap(*(q+1), *q); |
| 1235 | more = 1; |
| 1236 | } |
| 1237 | } while(more); |
| 1238 | } |
| 1239 | |
| 1240 | static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block) |
| 1241 | { |
| 1242 | struct dx_entry *entries = frame->entries; |
| 1243 | struct dx_entry *old = frame->at, *new = old + 1; |
| 1244 | int count = dx_get_count(entries); |
| 1245 | |
| 1246 | assert(count < dx_get_limit(entries)); |
| 1247 | assert(old < entries + count); |
| 1248 | memmove(new + 1, new, (char *)(entries + count) - (char *)(new)); |
| 1249 | dx_set_hash(new, hash); |
| 1250 | dx_set_block(new, block); |
| 1251 | dx_set_count(entries, count + 1); |
| 1252 | } |
| 1253 | |
| 1254 | /* |
| 1255 | * Test whether a directory entry matches the filename being searched for. |
| 1256 | * |
| 1257 | * Return: %true if the directory entry matches, otherwise %false. |
| 1258 | */ |
| 1259 | static inline bool ext4_match(const struct ext4_filename *fname, |
| 1260 | const struct ext4_dir_entry_2 *de) |
| 1261 | { |
| 1262 | struct fscrypt_name f; |
| 1263 | |
| 1264 | if (!de->inode) |
| 1265 | return false; |
| 1266 | |
| 1267 | f.usr_fname = fname->usr_fname; |
| 1268 | f.disk_name = fname->disk_name; |
| 1269 | #ifdef CONFIG_EXT4_FS_ENCRYPTION |
| 1270 | f.crypto_buf = fname->crypto_buf; |
| 1271 | #endif |
| 1272 | return fscrypt_match_name(&f, de->name, de->name_len); |
| 1273 | } |
| 1274 | |
| 1275 | /* |
| 1276 | * Returns 0 if not found, -1 on failure, and 1 on success |
| 1277 | */ |
| 1278 | int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size, |
| 1279 | struct inode *dir, struct ext4_filename *fname, |
| 1280 | unsigned int offset, struct ext4_dir_entry_2 **res_dir) |
| 1281 | { |
| 1282 | struct ext4_dir_entry_2 * de; |
| 1283 | char * dlimit; |
| 1284 | int de_len; |
| 1285 | |
| 1286 | de = (struct ext4_dir_entry_2 *)search_buf; |
| 1287 | dlimit = search_buf + buf_size; |
| 1288 | while ((char *) de < dlimit) { |
| 1289 | /* this code is executed quadratically often */ |
| 1290 | /* do minimal checking `by hand' */ |
| 1291 | if ((char *) de + de->name_len <= dlimit && |
| 1292 | ext4_match(fname, de)) { |
| 1293 | /* found a match - just to be sure, do |
| 1294 | * a full check */ |
| 1295 | if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data, |
| 1296 | bh->b_size, offset)) |
| 1297 | return -1; |
| 1298 | *res_dir = de; |
| 1299 | return 1; |
| 1300 | } |
| 1301 | /* prevent looping on a bad block */ |
| 1302 | de_len = ext4_rec_len_from_disk(de->rec_len, |
| 1303 | dir->i_sb->s_blocksize); |
| 1304 | if (de_len <= 0) |
| 1305 | return -1; |
| 1306 | offset += de_len; |
| 1307 | de = (struct ext4_dir_entry_2 *) ((char *) de + de_len); |
| 1308 | } |
| 1309 | return 0; |
| 1310 | } |
| 1311 | |
| 1312 | static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block, |
| 1313 | struct ext4_dir_entry *de) |
| 1314 | { |
| 1315 | struct super_block *sb = dir->i_sb; |
| 1316 | |
| 1317 | if (!is_dx(dir)) |
| 1318 | return 0; |
| 1319 | if (block == 0) |
| 1320 | return 1; |
| 1321 | if (de->inode == 0 && |
| 1322 | ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) == |
| 1323 | sb->s_blocksize) |
| 1324 | return 1; |
| 1325 | return 0; |
| 1326 | } |
| 1327 | |
| 1328 | /* |
| 1329 | * ext4_find_entry() |
| 1330 | * |
| 1331 | * finds an entry in the specified directory with the wanted name. It |
| 1332 | * returns the cache buffer in which the entry was found, and the entry |
| 1333 | * itself (as a parameter - res_dir). It does NOT read the inode of the |
| 1334 | * entry - you'll have to do that yourself if you want to. |
| 1335 | * |
| 1336 | * The returned buffer_head has ->b_count elevated. The caller is expected |
| 1337 | * to brelse() it when appropriate. |
| 1338 | */ |
| 1339 | static struct buffer_head * ext4_find_entry (struct inode *dir, |
| 1340 | const struct qstr *d_name, |
| 1341 | struct ext4_dir_entry_2 **res_dir, |
| 1342 | int *inlined) |
| 1343 | { |
| 1344 | struct super_block *sb; |
| 1345 | struct buffer_head *bh_use[NAMEI_RA_SIZE]; |
| 1346 | struct buffer_head *bh, *ret = NULL; |
| 1347 | ext4_lblk_t start, block; |
| 1348 | const u8 *name = d_name->name; |
| 1349 | size_t ra_max = 0; /* Number of bh's in the readahead |
| 1350 | buffer, bh_use[] */ |
| 1351 | size_t ra_ptr = 0; /* Current index into readahead |
| 1352 | buffer */ |
| 1353 | ext4_lblk_t nblocks; |
| 1354 | int i, namelen, retval; |
| 1355 | struct ext4_filename fname; |
| 1356 | |
| 1357 | *res_dir = NULL; |
| 1358 | sb = dir->i_sb; |
| 1359 | namelen = d_name->len; |
| 1360 | if (namelen > EXT4_NAME_LEN) |
| 1361 | return NULL; |
| 1362 | |
| 1363 | retval = ext4_fname_setup_filename(dir, d_name, 1, &fname); |
| 1364 | if (retval == -ENOENT) |
| 1365 | return NULL; |
| 1366 | if (retval) |
| 1367 | return ERR_PTR(retval); |
| 1368 | |
| 1369 | if (ext4_has_inline_data(dir)) { |
| 1370 | int has_inline_data = 1; |
| 1371 | ret = ext4_find_inline_entry(dir, &fname, res_dir, |
| 1372 | &has_inline_data); |
| 1373 | if (has_inline_data) { |
| 1374 | if (inlined) |
| 1375 | *inlined = 1; |
| 1376 | goto cleanup_and_exit; |
| 1377 | } |
| 1378 | } |
| 1379 | |
| 1380 | if ((namelen <= 2) && (name[0] == '.') && |
| 1381 | (name[1] == '.' || name[1] == '\0')) { |
| 1382 | /* |
| 1383 | * "." or ".." will only be in the first block |
| 1384 | * NFS may look up ".."; "." should be handled by the VFS |
| 1385 | */ |
| 1386 | block = start = 0; |
| 1387 | nblocks = 1; |
| 1388 | goto restart; |
| 1389 | } |
| 1390 | if (is_dx(dir)) { |
| 1391 | ret = ext4_dx_find_entry(dir, &fname, res_dir); |
| 1392 | /* |
| 1393 | * On success, or if the error was file not found, |
| 1394 | * return. Otherwise, fall back to doing a search the |
| 1395 | * old fashioned way. |
| 1396 | */ |
| 1397 | if (!IS_ERR(ret) || PTR_ERR(ret) != ERR_BAD_DX_DIR) |
| 1398 | goto cleanup_and_exit; |
| 1399 | dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, " |
| 1400 | "falling back\n")); |
| 1401 | ret = NULL; |
| 1402 | } |
| 1403 | nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); |
| 1404 | if (!nblocks) { |
| 1405 | ret = NULL; |
| 1406 | goto cleanup_and_exit; |
| 1407 | } |
| 1408 | start = EXT4_I(dir)->i_dir_start_lookup; |
| 1409 | if (start >= nblocks) |
| 1410 | start = 0; |
| 1411 | block = start; |
| 1412 | restart: |
| 1413 | do { |
| 1414 | /* |
| 1415 | * We deal with the read-ahead logic here. |
| 1416 | */ |
| 1417 | if (ra_ptr >= ra_max) { |
| 1418 | /* Refill the readahead buffer */ |
| 1419 | ra_ptr = 0; |
| 1420 | if (block < start) |
| 1421 | ra_max = start - block; |
| 1422 | else |
| 1423 | ra_max = nblocks - block; |
| 1424 | ra_max = min(ra_max, ARRAY_SIZE(bh_use)); |
| 1425 | retval = ext4_bread_batch(dir, block, ra_max, |
| 1426 | false /* wait */, bh_use); |
| 1427 | if (retval) { |
| 1428 | ret = ERR_PTR(retval); |
| 1429 | ra_max = 0; |
| 1430 | goto cleanup_and_exit; |
| 1431 | } |
| 1432 | } |
| 1433 | if ((bh = bh_use[ra_ptr++]) == NULL) |
| 1434 | goto next; |
| 1435 | wait_on_buffer(bh); |
| 1436 | if (!buffer_uptodate(bh)) { |
| 1437 | EXT4_ERROR_INODE(dir, "reading directory lblock %lu", |
| 1438 | (unsigned long) block); |
| 1439 | brelse(bh); |
| 1440 | ret = ERR_PTR(-EIO); |
| 1441 | goto cleanup_and_exit; |
| 1442 | } |
| 1443 | if (!buffer_verified(bh) && |
| 1444 | !is_dx_internal_node(dir, block, |
| 1445 | (struct ext4_dir_entry *)bh->b_data) && |
| 1446 | !ext4_dirent_csum_verify(dir, |
| 1447 | (struct ext4_dir_entry *)bh->b_data)) { |
| 1448 | EXT4_ERROR_INODE(dir, "checksumming directory " |
| 1449 | "block %lu", (unsigned long)block); |
| 1450 | brelse(bh); |
| 1451 | ret = ERR_PTR(-EFSBADCRC); |
| 1452 | goto cleanup_and_exit; |
| 1453 | } |
| 1454 | set_buffer_verified(bh); |
| 1455 | i = search_dirblock(bh, dir, &fname, |
| 1456 | block << EXT4_BLOCK_SIZE_BITS(sb), res_dir); |
| 1457 | if (i == 1) { |
| 1458 | EXT4_I(dir)->i_dir_start_lookup = block; |
| 1459 | ret = bh; |
| 1460 | goto cleanup_and_exit; |
| 1461 | } else { |
| 1462 | brelse(bh); |
| 1463 | if (i < 0) |
| 1464 | goto cleanup_and_exit; |
| 1465 | } |
| 1466 | next: |
| 1467 | if (++block >= nblocks) |
| 1468 | block = 0; |
| 1469 | } while (block != start); |
| 1470 | |
| 1471 | /* |
| 1472 | * If the directory has grown while we were searching, then |
| 1473 | * search the last part of the directory before giving up. |
| 1474 | */ |
| 1475 | block = nblocks; |
| 1476 | nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); |
| 1477 | if (block < nblocks) { |
| 1478 | start = 0; |
| 1479 | goto restart; |
| 1480 | } |
| 1481 | |
| 1482 | cleanup_and_exit: |
| 1483 | /* Clean up the read-ahead blocks */ |
| 1484 | for (; ra_ptr < ra_max; ra_ptr++) |
| 1485 | brelse(bh_use[ra_ptr]); |
| 1486 | ext4_fname_free_filename(&fname); |
| 1487 | return ret; |
| 1488 | } |
| 1489 | |
| 1490 | static struct buffer_head * ext4_dx_find_entry(struct inode *dir, |
| 1491 | struct ext4_filename *fname, |
| 1492 | struct ext4_dir_entry_2 **res_dir) |
| 1493 | { |
| 1494 | struct super_block * sb = dir->i_sb; |
| 1495 | struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; |
| 1496 | struct buffer_head *bh; |
| 1497 | ext4_lblk_t block; |
| 1498 | int retval; |
| 1499 | |
| 1500 | #ifdef CONFIG_EXT4_FS_ENCRYPTION |
| 1501 | *res_dir = NULL; |
| 1502 | #endif |
| 1503 | frame = dx_probe(fname, dir, NULL, frames); |
| 1504 | if (IS_ERR(frame)) |
| 1505 | return (struct buffer_head *) frame; |
| 1506 | do { |
| 1507 | block = dx_get_block(frame->at); |
| 1508 | bh = ext4_read_dirblock(dir, block, DIRENT); |
| 1509 | if (IS_ERR(bh)) |
| 1510 | goto errout; |
| 1511 | |
| 1512 | retval = search_dirblock(bh, dir, fname, |
| 1513 | block << EXT4_BLOCK_SIZE_BITS(sb), |
| 1514 | res_dir); |
| 1515 | if (retval == 1) |
| 1516 | goto success; |
| 1517 | brelse(bh); |
| 1518 | if (retval == -1) { |
| 1519 | bh = ERR_PTR(ERR_BAD_DX_DIR); |
| 1520 | goto errout; |
| 1521 | } |
| 1522 | |
| 1523 | /* Check to see if we should continue to search */ |
| 1524 | retval = ext4_htree_next_block(dir, fname->hinfo.hash, frame, |
| 1525 | frames, NULL); |
| 1526 | if (retval < 0) { |
| 1527 | ext4_warning_inode(dir, |
| 1528 | "error %d reading directory index block", |
| 1529 | retval); |
| 1530 | bh = ERR_PTR(retval); |
| 1531 | goto errout; |
| 1532 | } |
| 1533 | } while (retval == 1); |
| 1534 | |
| 1535 | bh = NULL; |
| 1536 | errout: |
| 1537 | dxtrace(printk(KERN_DEBUG "%s not found\n", fname->usr_fname->name)); |
| 1538 | success: |
| 1539 | dx_release(frames); |
| 1540 | return bh; |
| 1541 | } |
| 1542 | |
| 1543 | static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) |
| 1544 | { |
| 1545 | struct inode *inode; |
| 1546 | struct ext4_dir_entry_2 *de; |
| 1547 | struct buffer_head *bh; |
| 1548 | |
| 1549 | if (ext4_encrypted_inode(dir)) { |
| 1550 | int res = fscrypt_get_encryption_info(dir); |
| 1551 | |
| 1552 | /* |
| 1553 | * DCACHE_ENCRYPTED_WITH_KEY is set if the dentry is |
| 1554 | * created while the directory was encrypted and we |
| 1555 | * have access to the key. |
| 1556 | */ |
| 1557 | if (fscrypt_has_encryption_key(dir)) |
| 1558 | fscrypt_set_encrypted_dentry(dentry); |
| 1559 | fscrypt_set_d_op(dentry); |
| 1560 | if (res && res != -ENOKEY) |
| 1561 | return ERR_PTR(res); |
| 1562 | } |
| 1563 | |
| 1564 | if (dentry->d_name.len > EXT4_NAME_LEN) |
| 1565 | return ERR_PTR(-ENAMETOOLONG); |
| 1566 | |
| 1567 | bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); |
| 1568 | if (IS_ERR(bh)) |
| 1569 | return (struct dentry *) bh; |
| 1570 | inode = NULL; |
| 1571 | if (bh) { |
| 1572 | __u32 ino = le32_to_cpu(de->inode); |
| 1573 | brelse(bh); |
| 1574 | if (!ext4_valid_inum(dir->i_sb, ino)) { |
| 1575 | EXT4_ERROR_INODE(dir, "bad inode number: %u", ino); |
| 1576 | return ERR_PTR(-EFSCORRUPTED); |
| 1577 | } |
| 1578 | if (unlikely(ino == dir->i_ino)) { |
| 1579 | EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir", |
| 1580 | dentry); |
| 1581 | return ERR_PTR(-EFSCORRUPTED); |
| 1582 | } |
| 1583 | inode = ext4_iget_normal(dir->i_sb, ino); |
| 1584 | if (inode == ERR_PTR(-ESTALE)) { |
| 1585 | EXT4_ERROR_INODE(dir, |
| 1586 | "deleted inode referenced: %u", |
| 1587 | ino); |
| 1588 | return ERR_PTR(-EFSCORRUPTED); |
| 1589 | } |
| 1590 | if (!IS_ERR(inode) && ext4_encrypted_inode(dir) && |
| 1591 | (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) && |
| 1592 | !fscrypt_has_permitted_context(dir, inode)) { |
| 1593 | ext4_warning(inode->i_sb, |
| 1594 | "Inconsistent encryption contexts: %lu/%lu", |
| 1595 | dir->i_ino, inode->i_ino); |
| 1596 | iput(inode); |
| 1597 | return ERR_PTR(-EPERM); |
| 1598 | } |
| 1599 | } |
| 1600 | return d_splice_alias(inode, dentry); |
| 1601 | } |
| 1602 | |
| 1603 | |
| 1604 | struct dentry *ext4_get_parent(struct dentry *child) |
| 1605 | { |
| 1606 | __u32 ino; |
| 1607 | static const struct qstr dotdot = QSTR_INIT("..", 2); |
| 1608 | struct ext4_dir_entry_2 * de; |
| 1609 | struct buffer_head *bh; |
| 1610 | |
| 1611 | bh = ext4_find_entry(d_inode(child), &dotdot, &de, NULL); |
| 1612 | if (IS_ERR(bh)) |
| 1613 | return (struct dentry *) bh; |
| 1614 | if (!bh) |
| 1615 | return ERR_PTR(-ENOENT); |
| 1616 | ino = le32_to_cpu(de->inode); |
| 1617 | brelse(bh); |
| 1618 | |
| 1619 | if (!ext4_valid_inum(child->d_sb, ino)) { |
| 1620 | EXT4_ERROR_INODE(d_inode(child), |
| 1621 | "bad parent inode number: %u", ino); |
| 1622 | return ERR_PTR(-EFSCORRUPTED); |
| 1623 | } |
| 1624 | |
| 1625 | return d_obtain_alias(ext4_iget_normal(child->d_sb, ino)); |
| 1626 | } |
| 1627 | |
| 1628 | /* |
| 1629 | * Move count entries from end of map between two memory locations. |
| 1630 | * Returns pointer to last entry moved. |
| 1631 | */ |
| 1632 | static struct ext4_dir_entry_2 * |
| 1633 | dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count, |
| 1634 | unsigned blocksize) |
| 1635 | { |
| 1636 | unsigned rec_len = 0; |
| 1637 | |
| 1638 | while (count--) { |
| 1639 | struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *) |
| 1640 | (from + (map->offs<<2)); |
| 1641 | rec_len = EXT4_DIR_REC_LEN(de->name_len); |
| 1642 | memcpy (to, de, rec_len); |
| 1643 | ((struct ext4_dir_entry_2 *) to)->rec_len = |
| 1644 | ext4_rec_len_to_disk(rec_len, blocksize); |
| 1645 | de->inode = 0; |
| 1646 | map++; |
| 1647 | to += rec_len; |
| 1648 | } |
| 1649 | return (struct ext4_dir_entry_2 *) (to - rec_len); |
| 1650 | } |
| 1651 | |
| 1652 | /* |
| 1653 | * Compact each dir entry in the range to the minimal rec_len. |
| 1654 | * Returns pointer to last entry in range. |
| 1655 | */ |
| 1656 | static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize) |
| 1657 | { |
| 1658 | struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base; |
| 1659 | unsigned rec_len = 0; |
| 1660 | |
| 1661 | prev = to = de; |
| 1662 | while ((char*)de < base + blocksize) { |
| 1663 | next = ext4_next_entry(de, blocksize); |
| 1664 | if (de->inode && de->name_len) { |
| 1665 | rec_len = EXT4_DIR_REC_LEN(de->name_len); |
| 1666 | if (de > to) |
| 1667 | memmove(to, de, rec_len); |
| 1668 | to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize); |
| 1669 | prev = to; |
| 1670 | to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len); |
| 1671 | } |
| 1672 | de = next; |
| 1673 | } |
| 1674 | return prev; |
| 1675 | } |
| 1676 | |
| 1677 | /* |
| 1678 | * Split a full leaf block to make room for a new dir entry. |
| 1679 | * Allocate a new block, and move entries so that they are approx. equally full. |
| 1680 | * Returns pointer to de in block into which the new entry will be inserted. |
| 1681 | */ |
| 1682 | static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, |
| 1683 | struct buffer_head **bh,struct dx_frame *frame, |
| 1684 | struct dx_hash_info *hinfo) |
| 1685 | { |
| 1686 | unsigned blocksize = dir->i_sb->s_blocksize; |
| 1687 | unsigned count, continued; |
| 1688 | struct buffer_head *bh2; |
| 1689 | ext4_lblk_t newblock; |
| 1690 | u32 hash2; |
| 1691 | struct dx_map_entry *map; |
| 1692 | char *data1 = (*bh)->b_data, *data2; |
| 1693 | unsigned split, move, size; |
| 1694 | struct ext4_dir_entry_2 *de = NULL, *de2; |
| 1695 | struct ext4_dir_entry_tail *t; |
| 1696 | int csum_size = 0; |
| 1697 | int err = 0, i; |
| 1698 | |
| 1699 | if (ext4_has_metadata_csum(dir->i_sb)) |
| 1700 | csum_size = sizeof(struct ext4_dir_entry_tail); |
| 1701 | |
| 1702 | bh2 = ext4_append(handle, dir, &newblock); |
| 1703 | if (IS_ERR(bh2)) { |
| 1704 | brelse(*bh); |
| 1705 | *bh = NULL; |
| 1706 | return (struct ext4_dir_entry_2 *) bh2; |
| 1707 | } |
| 1708 | |
| 1709 | BUFFER_TRACE(*bh, "get_write_access"); |
| 1710 | err = ext4_journal_get_write_access(handle, *bh); |
| 1711 | if (err) |
| 1712 | goto journal_error; |
| 1713 | |
| 1714 | BUFFER_TRACE(frame->bh, "get_write_access"); |
| 1715 | err = ext4_journal_get_write_access(handle, frame->bh); |
| 1716 | if (err) |
| 1717 | goto journal_error; |
| 1718 | |
| 1719 | data2 = bh2->b_data; |
| 1720 | |
| 1721 | /* create map in the end of data2 block */ |
| 1722 | map = (struct dx_map_entry *) (data2 + blocksize); |
| 1723 | count = dx_make_map(dir, (struct ext4_dir_entry_2 *) data1, |
| 1724 | blocksize, hinfo, map); |
| 1725 | map -= count; |
| 1726 | dx_sort_map(map, count); |
| 1727 | /* Split the existing block in the middle, size-wise */ |
| 1728 | size = 0; |
| 1729 | move = 0; |
| 1730 | for (i = count-1; i >= 0; i--) { |
| 1731 | /* is more than half of this entry in 2nd half of the block? */ |
| 1732 | if (size + map[i].size/2 > blocksize/2) |
| 1733 | break; |
| 1734 | size += map[i].size; |
| 1735 | move++; |
| 1736 | } |
| 1737 | /* map index at which we will split */ |
| 1738 | split = count - move; |
| 1739 | hash2 = map[split].hash; |
| 1740 | continued = hash2 == map[split - 1].hash; |
| 1741 | dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n", |
| 1742 | (unsigned long)dx_get_block(frame->at), |
| 1743 | hash2, split, count-split)); |
| 1744 | |
| 1745 | /* Fancy dance to stay within two buffers */ |
| 1746 | de2 = dx_move_dirents(data1, data2, map + split, count - split, |
| 1747 | blocksize); |
| 1748 | de = dx_pack_dirents(data1, blocksize); |
| 1749 | de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) - |
| 1750 | (char *) de, |
| 1751 | blocksize); |
| 1752 | de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) - |
| 1753 | (char *) de2, |
| 1754 | blocksize); |
| 1755 | if (csum_size) { |
| 1756 | t = EXT4_DIRENT_TAIL(data2, blocksize); |
| 1757 | initialize_dirent_tail(t, blocksize); |
| 1758 | |
| 1759 | t = EXT4_DIRENT_TAIL(data1, blocksize); |
| 1760 | initialize_dirent_tail(t, blocksize); |
| 1761 | } |
| 1762 | |
| 1763 | dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1, |
| 1764 | blocksize, 1)); |
| 1765 | dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2, |
| 1766 | blocksize, 1)); |
| 1767 | |
| 1768 | /* Which block gets the new entry? */ |
| 1769 | if (hinfo->hash >= hash2) { |
| 1770 | swap(*bh, bh2); |
| 1771 | de = de2; |
| 1772 | } |
| 1773 | dx_insert_block(frame, hash2 + continued, newblock); |
| 1774 | err = ext4_handle_dirty_dirent_node(handle, dir, bh2); |
| 1775 | if (err) |
| 1776 | goto journal_error; |
| 1777 | err = ext4_handle_dirty_dx_node(handle, dir, frame->bh); |
| 1778 | if (err) |
| 1779 | goto journal_error; |
| 1780 | brelse(bh2); |
| 1781 | dxtrace(dx_show_index("frame", frame->entries)); |
| 1782 | return de; |
| 1783 | |
| 1784 | journal_error: |
| 1785 | brelse(*bh); |
| 1786 | brelse(bh2); |
| 1787 | *bh = NULL; |
| 1788 | ext4_std_error(dir->i_sb, err); |
| 1789 | return ERR_PTR(err); |
| 1790 | } |
| 1791 | |
| 1792 | int ext4_find_dest_de(struct inode *dir, struct inode *inode, |
| 1793 | struct buffer_head *bh, |
| 1794 | void *buf, int buf_size, |
| 1795 | struct ext4_filename *fname, |
| 1796 | struct ext4_dir_entry_2 **dest_de) |
| 1797 | { |
| 1798 | struct ext4_dir_entry_2 *de; |
| 1799 | unsigned short reclen = EXT4_DIR_REC_LEN(fname_len(fname)); |
| 1800 | int nlen, rlen; |
| 1801 | unsigned int offset = 0; |
| 1802 | char *top; |
| 1803 | |
| 1804 | de = (struct ext4_dir_entry_2 *)buf; |
| 1805 | top = buf + buf_size - reclen; |
| 1806 | while ((char *) de <= top) { |
| 1807 | if (ext4_check_dir_entry(dir, NULL, de, bh, |
| 1808 | buf, buf_size, offset)) |
| 1809 | return -EFSCORRUPTED; |
| 1810 | if (ext4_match(fname, de)) |
| 1811 | return -EEXIST; |
| 1812 | nlen = EXT4_DIR_REC_LEN(de->name_len); |
| 1813 | rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); |
| 1814 | if ((de->inode ? rlen - nlen : rlen) >= reclen) |
| 1815 | break; |
| 1816 | de = (struct ext4_dir_entry_2 *)((char *)de + rlen); |
| 1817 | offset += rlen; |
| 1818 | } |
| 1819 | if ((char *) de > top) |
| 1820 | return -ENOSPC; |
| 1821 | |
| 1822 | *dest_de = de; |
| 1823 | return 0; |
| 1824 | } |
| 1825 | |
| 1826 | void ext4_insert_dentry(struct inode *inode, |
| 1827 | struct ext4_dir_entry_2 *de, |
| 1828 | int buf_size, |
| 1829 | struct ext4_filename *fname) |
| 1830 | { |
| 1831 | |
| 1832 | int nlen, rlen; |
| 1833 | |
| 1834 | nlen = EXT4_DIR_REC_LEN(de->name_len); |
| 1835 | rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); |
| 1836 | if (de->inode) { |
| 1837 | struct ext4_dir_entry_2 *de1 = |
| 1838 | (struct ext4_dir_entry_2 *)((char *)de + nlen); |
| 1839 | de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size); |
| 1840 | de->rec_len = ext4_rec_len_to_disk(nlen, buf_size); |
| 1841 | de = de1; |
| 1842 | } |
| 1843 | de->file_type = EXT4_FT_UNKNOWN; |
| 1844 | de->inode = cpu_to_le32(inode->i_ino); |
| 1845 | ext4_set_de_type(inode->i_sb, de, inode->i_mode); |
| 1846 | de->name_len = fname_len(fname); |
| 1847 | memcpy(de->name, fname_name(fname), fname_len(fname)); |
| 1848 | } |
| 1849 | |
| 1850 | /* |
| 1851 | * Add a new entry into a directory (leaf) block. If de is non-NULL, |
| 1852 | * it points to a directory entry which is guaranteed to be large |
| 1853 | * enough for new directory entry. If de is NULL, then |
| 1854 | * add_dirent_to_buf will attempt search the directory block for |
| 1855 | * space. It will return -ENOSPC if no space is available, and -EIO |
| 1856 | * and -EEXIST if directory entry already exists. |
| 1857 | */ |
| 1858 | static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname, |
| 1859 | struct inode *dir, |
| 1860 | struct inode *inode, struct ext4_dir_entry_2 *de, |
| 1861 | struct buffer_head *bh) |
| 1862 | { |
| 1863 | unsigned int blocksize = dir->i_sb->s_blocksize; |
| 1864 | int csum_size = 0; |
| 1865 | int err; |
| 1866 | |
| 1867 | if (ext4_has_metadata_csum(inode->i_sb)) |
| 1868 | csum_size = sizeof(struct ext4_dir_entry_tail); |
| 1869 | |
| 1870 | if (!de) { |
| 1871 | err = ext4_find_dest_de(dir, inode, bh, bh->b_data, |
| 1872 | blocksize - csum_size, fname, &de); |
| 1873 | if (err) |
| 1874 | return err; |
| 1875 | } |
| 1876 | BUFFER_TRACE(bh, "get_write_access"); |
| 1877 | err = ext4_journal_get_write_access(handle, bh); |
| 1878 | if (err) { |
| 1879 | ext4_std_error(dir->i_sb, err); |
| 1880 | return err; |
| 1881 | } |
| 1882 | |
| 1883 | /* By now the buffer is marked for journaling */ |
| 1884 | ext4_insert_dentry(inode, de, blocksize, fname); |
| 1885 | |
| 1886 | /* |
| 1887 | * XXX shouldn't update any times until successful |
| 1888 | * completion of syscall, but too many callers depend |
| 1889 | * on this. |
| 1890 | * |
| 1891 | * XXX similarly, too many callers depend on |
| 1892 | * ext4_new_inode() setting the times, but error |
| 1893 | * recovery deletes the inode, so the worst that can |
| 1894 | * happen is that the times are slightly out of date |
| 1895 | * and/or different from the directory change time. |
| 1896 | */ |
| 1897 | dir->i_mtime = dir->i_ctime = current_time(dir); |
| 1898 | ext4_update_dx_flag(dir); |
| 1899 | inode_inc_iversion(dir); |
| 1900 | ext4_mark_inode_dirty(handle, dir); |
| 1901 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
| 1902 | err = ext4_handle_dirty_dirent_node(handle, dir, bh); |
| 1903 | if (err) |
| 1904 | ext4_std_error(dir->i_sb, err); |
| 1905 | return 0; |
| 1906 | } |
| 1907 | |
| 1908 | /* |
| 1909 | * This converts a one block unindexed directory to a 3 block indexed |
| 1910 | * directory, and adds the dentry to the indexed directory. |
| 1911 | */ |
| 1912 | static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname, |
| 1913 | struct inode *dir, |
| 1914 | struct inode *inode, struct buffer_head *bh) |
| 1915 | { |
| 1916 | struct buffer_head *bh2; |
| 1917 | struct dx_root *root; |
| 1918 | struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; |
| 1919 | struct dx_entry *entries; |
| 1920 | struct ext4_dir_entry_2 *de, *de2; |
| 1921 | struct ext4_dir_entry_tail *t; |
| 1922 | char *data1, *top; |
| 1923 | unsigned len; |
| 1924 | int retval; |
| 1925 | unsigned blocksize; |
| 1926 | ext4_lblk_t block; |
| 1927 | struct fake_dirent *fde; |
| 1928 | int csum_size = 0; |
| 1929 | |
| 1930 | if (ext4_has_metadata_csum(inode->i_sb)) |
| 1931 | csum_size = sizeof(struct ext4_dir_entry_tail); |
| 1932 | |
| 1933 | blocksize = dir->i_sb->s_blocksize; |
| 1934 | dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino)); |
| 1935 | BUFFER_TRACE(bh, "get_write_access"); |
| 1936 | retval = ext4_journal_get_write_access(handle, bh); |
| 1937 | if (retval) { |
| 1938 | ext4_std_error(dir->i_sb, retval); |
| 1939 | brelse(bh); |
| 1940 | return retval; |
| 1941 | } |
| 1942 | root = (struct dx_root *) bh->b_data; |
| 1943 | |
| 1944 | /* The 0th block becomes the root, move the dirents out */ |
| 1945 | fde = &root->dotdot; |
| 1946 | de = (struct ext4_dir_entry_2 *)((char *)fde + |
| 1947 | ext4_rec_len_from_disk(fde->rec_len, blocksize)); |
| 1948 | if ((char *) de >= (((char *) root) + blocksize)) { |
| 1949 | EXT4_ERROR_INODE(dir, "invalid rec_len for '..'"); |
| 1950 | brelse(bh); |
| 1951 | return -EFSCORRUPTED; |
| 1952 | } |
| 1953 | len = ((char *) root) + (blocksize - csum_size) - (char *) de; |
| 1954 | |
| 1955 | /* Allocate new block for the 0th block's dirents */ |
| 1956 | bh2 = ext4_append(handle, dir, &block); |
| 1957 | if (IS_ERR(bh2)) { |
| 1958 | brelse(bh); |
| 1959 | return PTR_ERR(bh2); |
| 1960 | } |
| 1961 | ext4_set_inode_flag(dir, EXT4_INODE_INDEX); |
| 1962 | data1 = bh2->b_data; |
| 1963 | |
| 1964 | memcpy (data1, de, len); |
| 1965 | de = (struct ext4_dir_entry_2 *) data1; |
| 1966 | top = data1 + len; |
| 1967 | while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top) |
| 1968 | de = de2; |
| 1969 | de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) - |
| 1970 | (char *) de, |
| 1971 | blocksize); |
| 1972 | |
| 1973 | if (csum_size) { |
| 1974 | t = EXT4_DIRENT_TAIL(data1, blocksize); |
| 1975 | initialize_dirent_tail(t, blocksize); |
| 1976 | } |
| 1977 | |
| 1978 | /* Initialize the root; the dot dirents already exist */ |
| 1979 | de = (struct ext4_dir_entry_2 *) (&root->dotdot); |
| 1980 | de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2), |
| 1981 | blocksize); |
| 1982 | memset (&root->info, 0, sizeof(root->info)); |
| 1983 | root->info.info_length = sizeof(root->info); |
| 1984 | root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; |
| 1985 | entries = root->entries; |
| 1986 | dx_set_block(entries, 1); |
| 1987 | dx_set_count(entries, 1); |
| 1988 | dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info))); |
| 1989 | |
| 1990 | /* Initialize as for dx_probe */ |
| 1991 | fname->hinfo.hash_version = root->info.hash_version; |
| 1992 | if (fname->hinfo.hash_version <= DX_HASH_TEA) |
| 1993 | fname->hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; |
| 1994 | fname->hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; |
| 1995 | ext4fs_dirhash(fname_name(fname), fname_len(fname), &fname->hinfo); |
| 1996 | |
| 1997 | memset(frames, 0, sizeof(frames)); |
| 1998 | frame = frames; |
| 1999 | frame->entries = entries; |
| 2000 | frame->at = entries; |
| 2001 | frame->bh = bh; |
| 2002 | |
| 2003 | retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh); |
| 2004 | if (retval) |
| 2005 | goto out_frames; |
| 2006 | retval = ext4_handle_dirty_dirent_node(handle, dir, bh2); |
| 2007 | if (retval) |
| 2008 | goto out_frames; |
| 2009 | |
| 2010 | de = do_split(handle,dir, &bh2, frame, &fname->hinfo); |
| 2011 | if (IS_ERR(de)) { |
| 2012 | retval = PTR_ERR(de); |
| 2013 | goto out_frames; |
| 2014 | } |
| 2015 | |
| 2016 | retval = add_dirent_to_buf(handle, fname, dir, inode, de, bh2); |
| 2017 | out_frames: |
| 2018 | /* |
| 2019 | * Even if the block split failed, we have to properly write |
| 2020 | * out all the changes we did so far. Otherwise we can end up |
| 2021 | * with corrupted filesystem. |
| 2022 | */ |
| 2023 | if (retval) |
| 2024 | ext4_mark_inode_dirty(handle, dir); |
| 2025 | dx_release(frames); |
| 2026 | brelse(bh2); |
| 2027 | return retval; |
| 2028 | } |
| 2029 | |
| 2030 | /* |
| 2031 | * ext4_add_entry() |
| 2032 | * |
| 2033 | * adds a file entry to the specified directory, using the same |
| 2034 | * semantics as ext4_find_entry(). It returns NULL if it failed. |
| 2035 | * |
| 2036 | * NOTE!! The inode part of 'de' is left at 0 - which means you |
| 2037 | * may not sleep between calling this and putting something into |
| 2038 | * the entry, as someone else might have used it while you slept. |
| 2039 | */ |
| 2040 | static int ext4_add_entry(handle_t *handle, struct dentry *dentry, |
| 2041 | struct inode *inode) |
| 2042 | { |
| 2043 | struct inode *dir = d_inode(dentry->d_parent); |
| 2044 | struct buffer_head *bh = NULL; |
| 2045 | struct ext4_dir_entry_2 *de; |
| 2046 | struct ext4_dir_entry_tail *t; |
| 2047 | struct super_block *sb; |
| 2048 | struct ext4_filename fname; |
| 2049 | int retval; |
| 2050 | int dx_fallback=0; |
| 2051 | unsigned blocksize; |
| 2052 | ext4_lblk_t block, blocks; |
| 2053 | int csum_size = 0; |
| 2054 | |
| 2055 | if (ext4_has_metadata_csum(inode->i_sb)) |
| 2056 | csum_size = sizeof(struct ext4_dir_entry_tail); |
| 2057 | |
| 2058 | sb = dir->i_sb; |
| 2059 | blocksize = sb->s_blocksize; |
| 2060 | if (!dentry->d_name.len) |
| 2061 | return -EINVAL; |
| 2062 | |
| 2063 | retval = ext4_fname_setup_filename(dir, &dentry->d_name, 0, &fname); |
| 2064 | if (retval) |
| 2065 | return retval; |
| 2066 | |
| 2067 | if (ext4_has_inline_data(dir)) { |
| 2068 | retval = ext4_try_add_inline_entry(handle, &fname, dir, inode); |
| 2069 | if (retval < 0) |
| 2070 | goto out; |
| 2071 | if (retval == 1) { |
| 2072 | retval = 0; |
| 2073 | goto out; |
| 2074 | } |
| 2075 | } |
| 2076 | |
| 2077 | if (is_dx(dir)) { |
| 2078 | retval = ext4_dx_add_entry(handle, &fname, dir, inode); |
| 2079 | if (!retval || (retval != ERR_BAD_DX_DIR)) |
| 2080 | goto out; |
| 2081 | ext4_clear_inode_flag(dir, EXT4_INODE_INDEX); |
| 2082 | dx_fallback++; |
| 2083 | ext4_mark_inode_dirty(handle, dir); |
| 2084 | } |
| 2085 | blocks = dir->i_size >> sb->s_blocksize_bits; |
| 2086 | for (block = 0; block < blocks; block++) { |
| 2087 | bh = ext4_read_dirblock(dir, block, DIRENT); |
| 2088 | if (IS_ERR(bh)) { |
| 2089 | retval = PTR_ERR(bh); |
| 2090 | bh = NULL; |
| 2091 | goto out; |
| 2092 | } |
| 2093 | retval = add_dirent_to_buf(handle, &fname, dir, inode, |
| 2094 | NULL, bh); |
| 2095 | if (retval != -ENOSPC) |
| 2096 | goto out; |
| 2097 | |
| 2098 | if (blocks == 1 && !dx_fallback && |
| 2099 | ext4_has_feature_dir_index(sb)) { |
| 2100 | retval = make_indexed_dir(handle, &fname, dir, |
| 2101 | inode, bh); |
| 2102 | bh = NULL; /* make_indexed_dir releases bh */ |
| 2103 | goto out; |
| 2104 | } |
| 2105 | brelse(bh); |
| 2106 | } |
| 2107 | bh = ext4_append(handle, dir, &block); |
| 2108 | if (IS_ERR(bh)) { |
| 2109 | retval = PTR_ERR(bh); |
| 2110 | bh = NULL; |
| 2111 | goto out; |
| 2112 | } |
| 2113 | de = (struct ext4_dir_entry_2 *) bh->b_data; |
| 2114 | de->inode = 0; |
| 2115 | de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize); |
| 2116 | |
| 2117 | if (csum_size) { |
| 2118 | t = EXT4_DIRENT_TAIL(bh->b_data, blocksize); |
| 2119 | initialize_dirent_tail(t, blocksize); |
| 2120 | } |
| 2121 | |
| 2122 | retval = add_dirent_to_buf(handle, &fname, dir, inode, de, bh); |
| 2123 | out: |
| 2124 | ext4_fname_free_filename(&fname); |
| 2125 | brelse(bh); |
| 2126 | if (retval == 0) |
| 2127 | ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY); |
| 2128 | return retval; |
| 2129 | } |
| 2130 | |
| 2131 | /* |
| 2132 | * Returns 0 for success, or a negative error value |
| 2133 | */ |
| 2134 | static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname, |
| 2135 | struct inode *dir, struct inode *inode) |
| 2136 | { |
| 2137 | struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; |
| 2138 | struct dx_entry *entries, *at; |
| 2139 | struct buffer_head *bh; |
| 2140 | struct super_block *sb = dir->i_sb; |
| 2141 | struct ext4_dir_entry_2 *de; |
| 2142 | int restart; |
| 2143 | int err; |
| 2144 | |
| 2145 | again: |
| 2146 | restart = 0; |
| 2147 | frame = dx_probe(fname, dir, NULL, frames); |
| 2148 | if (IS_ERR(frame)) |
| 2149 | return PTR_ERR(frame); |
| 2150 | entries = frame->entries; |
| 2151 | at = frame->at; |
| 2152 | bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT); |
| 2153 | if (IS_ERR(bh)) { |
| 2154 | err = PTR_ERR(bh); |
| 2155 | bh = NULL; |
| 2156 | goto cleanup; |
| 2157 | } |
| 2158 | |
| 2159 | BUFFER_TRACE(bh, "get_write_access"); |
| 2160 | err = ext4_journal_get_write_access(handle, bh); |
| 2161 | if (err) |
| 2162 | goto journal_error; |
| 2163 | |
| 2164 | err = add_dirent_to_buf(handle, fname, dir, inode, NULL, bh); |
| 2165 | if (err != -ENOSPC) |
| 2166 | goto cleanup; |
| 2167 | |
| 2168 | err = 0; |
| 2169 | /* Block full, should compress but for now just split */ |
| 2170 | dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n", |
| 2171 | dx_get_count(entries), dx_get_limit(entries))); |
| 2172 | /* Need to split index? */ |
| 2173 | if (dx_get_count(entries) == dx_get_limit(entries)) { |
| 2174 | ext4_lblk_t newblock; |
| 2175 | int levels = frame - frames + 1; |
| 2176 | unsigned int icount; |
| 2177 | int add_level = 1; |
| 2178 | struct dx_entry *entries2; |
| 2179 | struct dx_node *node2; |
| 2180 | struct buffer_head *bh2; |
| 2181 | |
| 2182 | while (frame > frames) { |
| 2183 | if (dx_get_count((frame - 1)->entries) < |
| 2184 | dx_get_limit((frame - 1)->entries)) { |
| 2185 | add_level = 0; |
| 2186 | break; |
| 2187 | } |
| 2188 | frame--; /* split higher index block */ |
| 2189 | at = frame->at; |
| 2190 | entries = frame->entries; |
| 2191 | restart = 1; |
| 2192 | } |
| 2193 | if (add_level && levels == ext4_dir_htree_level(sb)) { |
| 2194 | ext4_warning(sb, "Directory (ino: %lu) index full, " |
| 2195 | "reach max htree level :%d", |
| 2196 | dir->i_ino, levels); |
| 2197 | if (ext4_dir_htree_level(sb) < EXT4_HTREE_LEVEL) { |
| 2198 | ext4_warning(sb, "Large directory feature is " |
| 2199 | "not enabled on this " |
| 2200 | "filesystem"); |
| 2201 | } |
| 2202 | err = -ENOSPC; |
| 2203 | goto cleanup; |
| 2204 | } |
| 2205 | icount = dx_get_count(entries); |
| 2206 | bh2 = ext4_append(handle, dir, &newblock); |
| 2207 | if (IS_ERR(bh2)) { |
| 2208 | err = PTR_ERR(bh2); |
| 2209 | goto cleanup; |
| 2210 | } |
| 2211 | node2 = (struct dx_node *)(bh2->b_data); |
| 2212 | entries2 = node2->entries; |
| 2213 | memset(&node2->fake, 0, sizeof(struct fake_dirent)); |
| 2214 | node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize, |
| 2215 | sb->s_blocksize); |
| 2216 | BUFFER_TRACE(frame->bh, "get_write_access"); |
| 2217 | err = ext4_journal_get_write_access(handle, frame->bh); |
| 2218 | if (err) |
| 2219 | goto journal_error; |
| 2220 | if (!add_level) { |
| 2221 | unsigned icount1 = icount/2, icount2 = icount - icount1; |
| 2222 | unsigned hash2 = dx_get_hash(entries + icount1); |
| 2223 | dxtrace(printk(KERN_DEBUG "Split index %i/%i\n", |
| 2224 | icount1, icount2)); |
| 2225 | |
| 2226 | BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */ |
| 2227 | err = ext4_journal_get_write_access(handle, |
| 2228 | (frame - 1)->bh); |
| 2229 | if (err) |
| 2230 | goto journal_error; |
| 2231 | |
| 2232 | memcpy((char *) entries2, (char *) (entries + icount1), |
| 2233 | icount2 * sizeof(struct dx_entry)); |
| 2234 | dx_set_count(entries, icount1); |
| 2235 | dx_set_count(entries2, icount2); |
| 2236 | dx_set_limit(entries2, dx_node_limit(dir)); |
| 2237 | |
| 2238 | /* Which index block gets the new entry? */ |
| 2239 | if (at - entries >= icount1) { |
| 2240 | frame->at = at = at - entries - icount1 + entries2; |
| 2241 | frame->entries = entries = entries2; |
| 2242 | swap(frame->bh, bh2); |
| 2243 | } |
| 2244 | dx_insert_block((frame - 1), hash2, newblock); |
| 2245 | dxtrace(dx_show_index("node", frame->entries)); |
| 2246 | dxtrace(dx_show_index("node", |
| 2247 | ((struct dx_node *) bh2->b_data)->entries)); |
| 2248 | err = ext4_handle_dirty_dx_node(handle, dir, bh2); |
| 2249 | if (err) |
| 2250 | goto journal_error; |
| 2251 | brelse (bh2); |
| 2252 | err = ext4_handle_dirty_dx_node(handle, dir, |
| 2253 | (frame - 1)->bh); |
| 2254 | if (err) |
| 2255 | goto journal_error; |
| 2256 | if (restart) { |
| 2257 | err = ext4_handle_dirty_dx_node(handle, dir, |
| 2258 | frame->bh); |
| 2259 | goto journal_error; |
| 2260 | } |
| 2261 | } else { |
| 2262 | struct dx_root *dxroot; |
| 2263 | memcpy((char *) entries2, (char *) entries, |
| 2264 | icount * sizeof(struct dx_entry)); |
| 2265 | dx_set_limit(entries2, dx_node_limit(dir)); |
| 2266 | |
| 2267 | /* Set up root */ |
| 2268 | dx_set_count(entries, 1); |
| 2269 | dx_set_block(entries + 0, newblock); |
| 2270 | dxroot = (struct dx_root *)frames[0].bh->b_data; |
| 2271 | dxroot->info.indirect_levels += 1; |
| 2272 | dxtrace(printk(KERN_DEBUG |
| 2273 | "Creating %d level index...\n", |
| 2274 | info->indirect_levels)); |
| 2275 | err = ext4_handle_dirty_dx_node(handle, dir, frame->bh); |
| 2276 | if (err) |
| 2277 | goto journal_error; |
| 2278 | err = ext4_handle_dirty_dx_node(handle, dir, bh2); |
| 2279 | brelse(bh2); |
| 2280 | restart = 1; |
| 2281 | goto journal_error; |
| 2282 | } |
| 2283 | } |
| 2284 | de = do_split(handle, dir, &bh, frame, &fname->hinfo); |
| 2285 | if (IS_ERR(de)) { |
| 2286 | err = PTR_ERR(de); |
| 2287 | goto cleanup; |
| 2288 | } |
| 2289 | err = add_dirent_to_buf(handle, fname, dir, inode, de, bh); |
| 2290 | goto cleanup; |
| 2291 | |
| 2292 | journal_error: |
| 2293 | ext4_std_error(dir->i_sb, err); /* this is a no-op if err == 0 */ |
| 2294 | cleanup: |
| 2295 | brelse(bh); |
| 2296 | dx_release(frames); |
| 2297 | /* @restart is true means htree-path has been changed, we need to |
| 2298 | * repeat dx_probe() to find out valid htree-path |
| 2299 | */ |
| 2300 | if (restart && err == 0) |
| 2301 | goto again; |
| 2302 | return err; |
| 2303 | } |
| 2304 | |
| 2305 | /* |
| 2306 | * ext4_generic_delete_entry deletes a directory entry by merging it |
| 2307 | * with the previous entry |
| 2308 | */ |
| 2309 | int ext4_generic_delete_entry(handle_t *handle, |
| 2310 | struct inode *dir, |
| 2311 | struct ext4_dir_entry_2 *de_del, |
| 2312 | struct buffer_head *bh, |
| 2313 | void *entry_buf, |
| 2314 | int buf_size, |
| 2315 | int csum_size) |
| 2316 | { |
| 2317 | struct ext4_dir_entry_2 *de, *pde; |
| 2318 | unsigned int blocksize = dir->i_sb->s_blocksize; |
| 2319 | int i; |
| 2320 | |
| 2321 | i = 0; |
| 2322 | pde = NULL; |
| 2323 | de = (struct ext4_dir_entry_2 *)entry_buf; |
| 2324 | while (i < buf_size - csum_size) { |
| 2325 | if (ext4_check_dir_entry(dir, NULL, de, bh, |
| 2326 | bh->b_data, bh->b_size, i)) |
| 2327 | return -EFSCORRUPTED; |
| 2328 | if (de == de_del) { |
| 2329 | if (pde) |
| 2330 | pde->rec_len = ext4_rec_len_to_disk( |
| 2331 | ext4_rec_len_from_disk(pde->rec_len, |
| 2332 | blocksize) + |
| 2333 | ext4_rec_len_from_disk(de->rec_len, |
| 2334 | blocksize), |
| 2335 | blocksize); |
| 2336 | else |
| 2337 | de->inode = 0; |
| 2338 | inode_inc_iversion(dir); |
| 2339 | return 0; |
| 2340 | } |
| 2341 | i += ext4_rec_len_from_disk(de->rec_len, blocksize); |
| 2342 | pde = de; |
| 2343 | de = ext4_next_entry(de, blocksize); |
| 2344 | } |
| 2345 | return -ENOENT; |
| 2346 | } |
| 2347 | |
| 2348 | static int ext4_delete_entry(handle_t *handle, |
| 2349 | struct inode *dir, |
| 2350 | struct ext4_dir_entry_2 *de_del, |
| 2351 | struct buffer_head *bh) |
| 2352 | { |
| 2353 | int err, csum_size = 0; |
| 2354 | |
| 2355 | if (ext4_has_inline_data(dir)) { |
| 2356 | int has_inline_data = 1; |
| 2357 | err = ext4_delete_inline_entry(handle, dir, de_del, bh, |
| 2358 | &has_inline_data); |
| 2359 | if (has_inline_data) |
| 2360 | return err; |
| 2361 | } |
| 2362 | |
| 2363 | if (ext4_has_metadata_csum(dir->i_sb)) |
| 2364 | csum_size = sizeof(struct ext4_dir_entry_tail); |
| 2365 | |
| 2366 | BUFFER_TRACE(bh, "get_write_access"); |
| 2367 | err = ext4_journal_get_write_access(handle, bh); |
| 2368 | if (unlikely(err)) |
| 2369 | goto out; |
| 2370 | |
| 2371 | err = ext4_generic_delete_entry(handle, dir, de_del, |
| 2372 | bh, bh->b_data, |
| 2373 | dir->i_sb->s_blocksize, csum_size); |
| 2374 | if (err) |
| 2375 | goto out; |
| 2376 | |
| 2377 | BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); |
| 2378 | err = ext4_handle_dirty_dirent_node(handle, dir, bh); |
| 2379 | if (unlikely(err)) |
| 2380 | goto out; |
| 2381 | |
| 2382 | return 0; |
| 2383 | out: |
| 2384 | if (err != -ENOENT) |
| 2385 | ext4_std_error(dir->i_sb, err); |
| 2386 | return err; |
| 2387 | } |
| 2388 | |
| 2389 | /* |
| 2390 | * Set directory link count to 1 if nlinks > EXT4_LINK_MAX, or if nlinks == 2 |
| 2391 | * since this indicates that nlinks count was previously 1 to avoid overflowing |
| 2392 | * the 16-bit i_links_count field on disk. Directories with i_nlink == 1 mean |
| 2393 | * that subdirectory link counts are not being maintained accurately. |
| 2394 | * |
| 2395 | * The caller has already checked for i_nlink overflow in case the DIR_LINK |
| 2396 | * feature is not enabled and returned -EMLINK. The is_dx() check is a proxy |
| 2397 | * for checking S_ISDIR(inode) (since the INODE_INDEX feature will not be set |
| 2398 | * on regular files) and to avoid creating huge/slow non-HTREE directories. |
| 2399 | */ |
| 2400 | static void ext4_inc_count(handle_t *handle, struct inode *inode) |
| 2401 | { |
| 2402 | inc_nlink(inode); |
| 2403 | if (is_dx(inode) && |
| 2404 | (inode->i_nlink > EXT4_LINK_MAX || inode->i_nlink == 2)) |
| 2405 | set_nlink(inode, 1); |
| 2406 | } |
| 2407 | |
| 2408 | /* |
| 2409 | * If a directory had nlink == 1, then we should let it be 1. This indicates |
| 2410 | * directory has >EXT4_LINK_MAX subdirs. |
| 2411 | */ |
| 2412 | static void ext4_dec_count(handle_t *handle, struct inode *inode) |
| 2413 | { |
| 2414 | if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2) |
| 2415 | drop_nlink(inode); |
| 2416 | } |
| 2417 | |
| 2418 | |
| 2419 | static int ext4_add_nondir(handle_t *handle, |
| 2420 | struct dentry *dentry, struct inode *inode) |
| 2421 | { |
| 2422 | int err = ext4_add_entry(handle, dentry, inode); |
| 2423 | if (!err) { |
| 2424 | ext4_mark_inode_dirty(handle, inode); |
| 2425 | d_instantiate_new(dentry, inode); |
| 2426 | return 0; |
| 2427 | } |
| 2428 | drop_nlink(inode); |
| 2429 | unlock_new_inode(inode); |
| 2430 | iput(inode); |
| 2431 | return err; |
| 2432 | } |
| 2433 | |
| 2434 | /* |
| 2435 | * By the time this is called, we already have created |
| 2436 | * the directory cache entry for the new file, but it |
| 2437 | * is so far negative - it has no inode. |
| 2438 | * |
| 2439 | * If the create succeeds, we fill in the inode information |
| 2440 | * with d_instantiate(). |
| 2441 | */ |
| 2442 | static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode, |
| 2443 | bool excl) |
| 2444 | { |
| 2445 | handle_t *handle; |
| 2446 | struct inode *inode; |
| 2447 | int err, credits, retries = 0; |
| 2448 | |
| 2449 | err = dquot_initialize(dir); |
| 2450 | if (err) |
| 2451 | return err; |
| 2452 | |
| 2453 | credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + |
| 2454 | EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); |
| 2455 | retry: |
| 2456 | inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0, |
| 2457 | NULL, EXT4_HT_DIR, credits); |
| 2458 | handle = ext4_journal_current_handle(); |
| 2459 | err = PTR_ERR(inode); |
| 2460 | if (!IS_ERR(inode)) { |
| 2461 | inode->i_op = &ext4_file_inode_operations; |
| 2462 | inode->i_fop = &ext4_file_operations; |
| 2463 | ext4_set_aops(inode); |
| 2464 | err = ext4_add_nondir(handle, dentry, inode); |
| 2465 | if (!err && IS_DIRSYNC(dir)) |
| 2466 | ext4_handle_sync(handle); |
| 2467 | } |
| 2468 | if (handle) |
| 2469 | ext4_journal_stop(handle); |
| 2470 | if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) |
| 2471 | goto retry; |
| 2472 | return err; |
| 2473 | } |
| 2474 | |
| 2475 | static int ext4_mknod(struct inode *dir, struct dentry *dentry, |
| 2476 | umode_t mode, dev_t rdev) |
| 2477 | { |
| 2478 | handle_t *handle; |
| 2479 | struct inode *inode; |
| 2480 | int err, credits, retries = 0; |
| 2481 | |
| 2482 | err = dquot_initialize(dir); |
| 2483 | if (err) |
| 2484 | return err; |
| 2485 | |
| 2486 | credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + |
| 2487 | EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); |
| 2488 | retry: |
| 2489 | inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0, |
| 2490 | NULL, EXT4_HT_DIR, credits); |
| 2491 | handle = ext4_journal_current_handle(); |
| 2492 | err = PTR_ERR(inode); |
| 2493 | if (!IS_ERR(inode)) { |
| 2494 | init_special_inode(inode, inode->i_mode, rdev); |
| 2495 | inode->i_op = &ext4_special_inode_operations; |
| 2496 | err = ext4_add_nondir(handle, dentry, inode); |
| 2497 | if (!err && IS_DIRSYNC(dir)) |
| 2498 | ext4_handle_sync(handle); |
| 2499 | } |
| 2500 | if (handle) |
| 2501 | ext4_journal_stop(handle); |
| 2502 | if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) |
| 2503 | goto retry; |
| 2504 | return err; |
| 2505 | } |
| 2506 | |
| 2507 | static int ext4_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) |
| 2508 | { |
| 2509 | handle_t *handle; |
| 2510 | struct inode *inode; |
| 2511 | int err, retries = 0; |
| 2512 | |
| 2513 | err = dquot_initialize(dir); |
| 2514 | if (err) |
| 2515 | return err; |
| 2516 | |
| 2517 | retry: |
| 2518 | inode = ext4_new_inode_start_handle(dir, mode, |
| 2519 | NULL, 0, NULL, |
| 2520 | EXT4_HT_DIR, |
| 2521 | EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + |
| 2522 | 4 + EXT4_XATTR_TRANS_BLOCKS); |
| 2523 | handle = ext4_journal_current_handle(); |
| 2524 | err = PTR_ERR(inode); |
| 2525 | if (!IS_ERR(inode)) { |
| 2526 | inode->i_op = &ext4_file_inode_operations; |
| 2527 | inode->i_fop = &ext4_file_operations; |
| 2528 | ext4_set_aops(inode); |
| 2529 | d_tmpfile(dentry, inode); |
| 2530 | err = ext4_orphan_add(handle, inode); |
| 2531 | if (err) |
| 2532 | goto err_unlock_inode; |
| 2533 | mark_inode_dirty(inode); |
| 2534 | unlock_new_inode(inode); |
| 2535 | } |
| 2536 | if (handle) |
| 2537 | ext4_journal_stop(handle); |
| 2538 | if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) |
| 2539 | goto retry; |
| 2540 | return err; |
| 2541 | err_unlock_inode: |
| 2542 | ext4_journal_stop(handle); |
| 2543 | unlock_new_inode(inode); |
| 2544 | return err; |
| 2545 | } |
| 2546 | |
| 2547 | struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode, |
| 2548 | struct ext4_dir_entry_2 *de, |
| 2549 | int blocksize, int csum_size, |
| 2550 | unsigned int parent_ino, int dotdot_real_len) |
| 2551 | { |
| 2552 | de->inode = cpu_to_le32(inode->i_ino); |
| 2553 | de->name_len = 1; |
| 2554 | de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len), |
| 2555 | blocksize); |
| 2556 | strcpy(de->name, "."); |
| 2557 | ext4_set_de_type(inode->i_sb, de, S_IFDIR); |
| 2558 | |
| 2559 | de = ext4_next_entry(de, blocksize); |
| 2560 | de->inode = cpu_to_le32(parent_ino); |
| 2561 | de->name_len = 2; |
| 2562 | if (!dotdot_real_len) |
| 2563 | de->rec_len = ext4_rec_len_to_disk(blocksize - |
| 2564 | (csum_size + EXT4_DIR_REC_LEN(1)), |
| 2565 | blocksize); |
| 2566 | else |
| 2567 | de->rec_len = ext4_rec_len_to_disk( |
| 2568 | EXT4_DIR_REC_LEN(de->name_len), blocksize); |
| 2569 | strcpy(de->name, ".."); |
| 2570 | ext4_set_de_type(inode->i_sb, de, S_IFDIR); |
| 2571 | |
| 2572 | return ext4_next_entry(de, blocksize); |
| 2573 | } |
| 2574 | |
| 2575 | static int ext4_init_new_dir(handle_t *handle, struct inode *dir, |
| 2576 | struct inode *inode) |
| 2577 | { |
| 2578 | struct buffer_head *dir_block = NULL; |
| 2579 | struct ext4_dir_entry_2 *de; |
| 2580 | struct ext4_dir_entry_tail *t; |
| 2581 | ext4_lblk_t block = 0; |
| 2582 | unsigned int blocksize = dir->i_sb->s_blocksize; |
| 2583 | int csum_size = 0; |
| 2584 | int err; |
| 2585 | |
| 2586 | if (ext4_has_metadata_csum(dir->i_sb)) |
| 2587 | csum_size = sizeof(struct ext4_dir_entry_tail); |
| 2588 | |
| 2589 | if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) { |
| 2590 | err = ext4_try_create_inline_dir(handle, dir, inode); |
| 2591 | if (err < 0 && err != -ENOSPC) |
| 2592 | goto out; |
| 2593 | if (!err) |
| 2594 | goto out; |
| 2595 | } |
| 2596 | |
| 2597 | inode->i_size = 0; |
| 2598 | dir_block = ext4_append(handle, inode, &block); |
| 2599 | if (IS_ERR(dir_block)) |
| 2600 | return PTR_ERR(dir_block); |
| 2601 | de = (struct ext4_dir_entry_2 *)dir_block->b_data; |
| 2602 | ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0); |
| 2603 | set_nlink(inode, 2); |
| 2604 | if (csum_size) { |
| 2605 | t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize); |
| 2606 | initialize_dirent_tail(t, blocksize); |
| 2607 | } |
| 2608 | |
| 2609 | BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata"); |
| 2610 | err = ext4_handle_dirty_dirent_node(handle, inode, dir_block); |
| 2611 | if (err) |
| 2612 | goto out; |
| 2613 | set_buffer_verified(dir_block); |
| 2614 | out: |
| 2615 | brelse(dir_block); |
| 2616 | return err; |
| 2617 | } |
| 2618 | |
| 2619 | static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) |
| 2620 | { |
| 2621 | handle_t *handle; |
| 2622 | struct inode *inode; |
| 2623 | int err, credits, retries = 0; |
| 2624 | |
| 2625 | if (EXT4_DIR_LINK_MAX(dir)) |
| 2626 | return -EMLINK; |
| 2627 | |
| 2628 | err = dquot_initialize(dir); |
| 2629 | if (err) |
| 2630 | return err; |
| 2631 | |
| 2632 | credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + |
| 2633 | EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); |
| 2634 | retry: |
| 2635 | inode = ext4_new_inode_start_handle(dir, S_IFDIR | mode, |
| 2636 | &dentry->d_name, |
| 2637 | 0, NULL, EXT4_HT_DIR, credits); |
| 2638 | handle = ext4_journal_current_handle(); |
| 2639 | err = PTR_ERR(inode); |
| 2640 | if (IS_ERR(inode)) |
| 2641 | goto out_stop; |
| 2642 | |
| 2643 | inode->i_op = &ext4_dir_inode_operations; |
| 2644 | inode->i_fop = &ext4_dir_operations; |
| 2645 | err = ext4_init_new_dir(handle, dir, inode); |
| 2646 | if (err) |
| 2647 | goto out_clear_inode; |
| 2648 | err = ext4_mark_inode_dirty(handle, inode); |
| 2649 | if (!err) |
| 2650 | err = ext4_add_entry(handle, dentry, inode); |
| 2651 | if (err) { |
| 2652 | out_clear_inode: |
| 2653 | clear_nlink(inode); |
| 2654 | unlock_new_inode(inode); |
| 2655 | ext4_mark_inode_dirty(handle, inode); |
| 2656 | iput(inode); |
| 2657 | goto out_stop; |
| 2658 | } |
| 2659 | ext4_inc_count(handle, dir); |
| 2660 | ext4_update_dx_flag(dir); |
| 2661 | err = ext4_mark_inode_dirty(handle, dir); |
| 2662 | if (err) |
| 2663 | goto out_clear_inode; |
| 2664 | d_instantiate_new(dentry, inode); |
| 2665 | if (IS_DIRSYNC(dir)) |
| 2666 | ext4_handle_sync(handle); |
| 2667 | |
| 2668 | out_stop: |
| 2669 | if (handle) |
| 2670 | ext4_journal_stop(handle); |
| 2671 | if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) |
| 2672 | goto retry; |
| 2673 | return err; |
| 2674 | } |
| 2675 | |
| 2676 | /* |
| 2677 | * routine to check that the specified directory is empty (for rmdir) |
| 2678 | */ |
| 2679 | bool ext4_empty_dir(struct inode *inode) |
| 2680 | { |
| 2681 | unsigned int offset; |
| 2682 | struct buffer_head *bh; |
| 2683 | struct ext4_dir_entry_2 *de, *de1; |
| 2684 | struct super_block *sb; |
| 2685 | |
| 2686 | if (ext4_has_inline_data(inode)) { |
| 2687 | int has_inline_data = 1; |
| 2688 | int ret; |
| 2689 | |
| 2690 | ret = empty_inline_dir(inode, &has_inline_data); |
| 2691 | if (has_inline_data) |
| 2692 | return ret; |
| 2693 | } |
| 2694 | |
| 2695 | sb = inode->i_sb; |
| 2696 | if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) { |
| 2697 | EXT4_ERROR_INODE(inode, "invalid size"); |
| 2698 | return true; |
| 2699 | } |
| 2700 | bh = ext4_read_dirblock(inode, 0, EITHER); |
| 2701 | if (IS_ERR(bh)) |
| 2702 | return true; |
| 2703 | |
| 2704 | de = (struct ext4_dir_entry_2 *) bh->b_data; |
| 2705 | de1 = ext4_next_entry(de, sb->s_blocksize); |
| 2706 | if (le32_to_cpu(de->inode) != inode->i_ino || |
| 2707 | le32_to_cpu(de1->inode) == 0 || |
| 2708 | strcmp(".", de->name) || strcmp("..", de1->name)) { |
| 2709 | ext4_warning_inode(inode, "directory missing '.' and/or '..'"); |
| 2710 | brelse(bh); |
| 2711 | return true; |
| 2712 | } |
| 2713 | offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) + |
| 2714 | ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize); |
| 2715 | de = ext4_next_entry(de1, sb->s_blocksize); |
| 2716 | while (offset < inode->i_size) { |
| 2717 | if ((void *) de >= (void *) (bh->b_data+sb->s_blocksize)) { |
| 2718 | unsigned int lblock; |
| 2719 | brelse(bh); |
| 2720 | lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb); |
| 2721 | bh = ext4_read_dirblock(inode, lblock, EITHER); |
| 2722 | if (IS_ERR(bh)) |
| 2723 | return true; |
| 2724 | de = (struct ext4_dir_entry_2 *) bh->b_data; |
| 2725 | } |
| 2726 | if (ext4_check_dir_entry(inode, NULL, de, bh, |
| 2727 | bh->b_data, bh->b_size, offset)) { |
| 2728 | de = (struct ext4_dir_entry_2 *)(bh->b_data + |
| 2729 | sb->s_blocksize); |
| 2730 | offset = (offset | (sb->s_blocksize - 1)) + 1; |
| 2731 | continue; |
| 2732 | } |
| 2733 | if (le32_to_cpu(de->inode)) { |
| 2734 | brelse(bh); |
| 2735 | return false; |
| 2736 | } |
| 2737 | offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); |
| 2738 | de = ext4_next_entry(de, sb->s_blocksize); |
| 2739 | } |
| 2740 | brelse(bh); |
| 2741 | return true; |
| 2742 | } |
| 2743 | |
| 2744 | /* |
| 2745 | * ext4_orphan_add() links an unlinked or truncated inode into a list of |
| 2746 | * such inodes, starting at the superblock, in case we crash before the |
| 2747 | * file is closed/deleted, or in case the inode truncate spans multiple |
| 2748 | * transactions and the last transaction is not recovered after a crash. |
| 2749 | * |
| 2750 | * At filesystem recovery time, we walk this list deleting unlinked |
| 2751 | * inodes and truncating linked inodes in ext4_orphan_cleanup(). |
| 2752 | * |
| 2753 | * Orphan list manipulation functions must be called under i_mutex unless |
| 2754 | * we are just creating the inode or deleting it. |
| 2755 | */ |
| 2756 | int ext4_orphan_add(handle_t *handle, struct inode *inode) |
| 2757 | { |
| 2758 | struct super_block *sb = inode->i_sb; |
| 2759 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 2760 | struct ext4_iloc iloc; |
| 2761 | int err = 0, rc; |
| 2762 | bool dirty = false; |
| 2763 | |
| 2764 | if (!sbi->s_journal || is_bad_inode(inode)) |
| 2765 | return 0; |
| 2766 | |
| 2767 | WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && |
| 2768 | !inode_is_locked(inode)); |
| 2769 | /* |
| 2770 | * Exit early if inode already is on orphan list. This is a big speedup |
| 2771 | * since we don't have to contend on the global s_orphan_lock. |
| 2772 | */ |
| 2773 | if (!list_empty(&EXT4_I(inode)->i_orphan)) |
| 2774 | return 0; |
| 2775 | |
| 2776 | /* |
| 2777 | * Orphan handling is only valid for files with data blocks |
| 2778 | * being truncated, or files being unlinked. Note that we either |
| 2779 | * hold i_mutex, or the inode can not be referenced from outside, |
| 2780 | * so i_nlink should not be bumped due to race |
| 2781 | */ |
| 2782 | J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || |
| 2783 | S_ISLNK(inode->i_mode)) || inode->i_nlink == 0); |
| 2784 | |
| 2785 | BUFFER_TRACE(sbi->s_sbh, "get_write_access"); |
| 2786 | err = ext4_journal_get_write_access(handle, sbi->s_sbh); |
| 2787 | if (err) |
| 2788 | goto out; |
| 2789 | |
| 2790 | err = ext4_reserve_inode_write(handle, inode, &iloc); |
| 2791 | if (err) |
| 2792 | goto out; |
| 2793 | |
| 2794 | mutex_lock(&sbi->s_orphan_lock); |
| 2795 | /* |
| 2796 | * Due to previous errors inode may be already a part of on-disk |
| 2797 | * orphan list. If so skip on-disk list modification. |
| 2798 | */ |
| 2799 | if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) > |
| 2800 | (le32_to_cpu(sbi->s_es->s_inodes_count))) { |
| 2801 | /* Insert this inode at the head of the on-disk orphan list */ |
| 2802 | NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan); |
| 2803 | sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino); |
| 2804 | dirty = true; |
| 2805 | } |
| 2806 | list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan); |
| 2807 | mutex_unlock(&sbi->s_orphan_lock); |
| 2808 | |
| 2809 | if (dirty) { |
| 2810 | err = ext4_handle_dirty_super(handle, sb); |
| 2811 | rc = ext4_mark_iloc_dirty(handle, inode, &iloc); |
| 2812 | if (!err) |
| 2813 | err = rc; |
| 2814 | if (err) { |
| 2815 | /* |
| 2816 | * We have to remove inode from in-memory list if |
| 2817 | * addition to on disk orphan list failed. Stray orphan |
| 2818 | * list entries can cause panics at unmount time. |
| 2819 | */ |
| 2820 | mutex_lock(&sbi->s_orphan_lock); |
| 2821 | list_del_init(&EXT4_I(inode)->i_orphan); |
| 2822 | mutex_unlock(&sbi->s_orphan_lock); |
| 2823 | } |
| 2824 | } else |
| 2825 | brelse(iloc.bh); |
| 2826 | |
| 2827 | jbd_debug(4, "superblock will point to %lu\n", inode->i_ino); |
| 2828 | jbd_debug(4, "orphan inode %lu will point to %d\n", |
| 2829 | inode->i_ino, NEXT_ORPHAN(inode)); |
| 2830 | out: |
| 2831 | ext4_std_error(sb, err); |
| 2832 | return err; |
| 2833 | } |
| 2834 | |
| 2835 | /* |
| 2836 | * ext4_orphan_del() removes an unlinked or truncated inode from the list |
| 2837 | * of such inodes stored on disk, because it is finally being cleaned up. |
| 2838 | */ |
| 2839 | int ext4_orphan_del(handle_t *handle, struct inode *inode) |
| 2840 | { |
| 2841 | struct list_head *prev; |
| 2842 | struct ext4_inode_info *ei = EXT4_I(inode); |
| 2843 | struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
| 2844 | __u32 ino_next; |
| 2845 | struct ext4_iloc iloc; |
| 2846 | int err = 0; |
| 2847 | |
| 2848 | if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS)) |
| 2849 | return 0; |
| 2850 | |
| 2851 | WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && |
| 2852 | !inode_is_locked(inode)); |
| 2853 | /* Do this quick check before taking global s_orphan_lock. */ |
| 2854 | if (list_empty(&ei->i_orphan)) |
| 2855 | return 0; |
| 2856 | |
| 2857 | if (handle) { |
| 2858 | /* Grab inode buffer early before taking global s_orphan_lock */ |
| 2859 | err = ext4_reserve_inode_write(handle, inode, &iloc); |
| 2860 | } |
| 2861 | |
| 2862 | mutex_lock(&sbi->s_orphan_lock); |
| 2863 | jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino); |
| 2864 | |
| 2865 | prev = ei->i_orphan.prev; |
| 2866 | list_del_init(&ei->i_orphan); |
| 2867 | |
| 2868 | /* If we're on an error path, we may not have a valid |
| 2869 | * transaction handle with which to update the orphan list on |
| 2870 | * disk, but we still need to remove the inode from the linked |
| 2871 | * list in memory. */ |
| 2872 | if (!handle || err) { |
| 2873 | mutex_unlock(&sbi->s_orphan_lock); |
| 2874 | goto out_err; |
| 2875 | } |
| 2876 | |
| 2877 | ino_next = NEXT_ORPHAN(inode); |
| 2878 | if (prev == &sbi->s_orphan) { |
| 2879 | jbd_debug(4, "superblock will point to %u\n", ino_next); |
| 2880 | BUFFER_TRACE(sbi->s_sbh, "get_write_access"); |
| 2881 | err = ext4_journal_get_write_access(handle, sbi->s_sbh); |
| 2882 | if (err) { |
| 2883 | mutex_unlock(&sbi->s_orphan_lock); |
| 2884 | goto out_brelse; |
| 2885 | } |
| 2886 | sbi->s_es->s_last_orphan = cpu_to_le32(ino_next); |
| 2887 | mutex_unlock(&sbi->s_orphan_lock); |
| 2888 | err = ext4_handle_dirty_super(handle, inode->i_sb); |
| 2889 | } else { |
| 2890 | struct ext4_iloc iloc2; |
| 2891 | struct inode *i_prev = |
| 2892 | &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode; |
| 2893 | |
| 2894 | jbd_debug(4, "orphan inode %lu will point to %u\n", |
| 2895 | i_prev->i_ino, ino_next); |
| 2896 | err = ext4_reserve_inode_write(handle, i_prev, &iloc2); |
| 2897 | if (err) { |
| 2898 | mutex_unlock(&sbi->s_orphan_lock); |
| 2899 | goto out_brelse; |
| 2900 | } |
| 2901 | NEXT_ORPHAN(i_prev) = ino_next; |
| 2902 | err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2); |
| 2903 | mutex_unlock(&sbi->s_orphan_lock); |
| 2904 | } |
| 2905 | if (err) |
| 2906 | goto out_brelse; |
| 2907 | NEXT_ORPHAN(inode) = 0; |
| 2908 | err = ext4_mark_iloc_dirty(handle, inode, &iloc); |
| 2909 | out_err: |
| 2910 | ext4_std_error(inode->i_sb, err); |
| 2911 | return err; |
| 2912 | |
| 2913 | out_brelse: |
| 2914 | brelse(iloc.bh); |
| 2915 | goto out_err; |
| 2916 | } |
| 2917 | |
| 2918 | static int ext4_rmdir(struct inode *dir, struct dentry *dentry) |
| 2919 | { |
| 2920 | int retval; |
| 2921 | struct inode *inode; |
| 2922 | struct buffer_head *bh; |
| 2923 | struct ext4_dir_entry_2 *de; |
| 2924 | handle_t *handle = NULL; |
| 2925 | |
| 2926 | if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) |
| 2927 | return -EIO; |
| 2928 | |
| 2929 | /* Initialize quotas before so that eventual writes go in |
| 2930 | * separate transaction */ |
| 2931 | retval = dquot_initialize(dir); |
| 2932 | if (retval) |
| 2933 | return retval; |
| 2934 | retval = dquot_initialize(d_inode(dentry)); |
| 2935 | if (retval) |
| 2936 | return retval; |
| 2937 | |
| 2938 | retval = -ENOENT; |
| 2939 | bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); |
| 2940 | if (IS_ERR(bh)) |
| 2941 | return PTR_ERR(bh); |
| 2942 | if (!bh) |
| 2943 | goto end_rmdir; |
| 2944 | |
| 2945 | inode = d_inode(dentry); |
| 2946 | |
| 2947 | retval = -EFSCORRUPTED; |
| 2948 | if (le32_to_cpu(de->inode) != inode->i_ino) |
| 2949 | goto end_rmdir; |
| 2950 | |
| 2951 | retval = -ENOTEMPTY; |
| 2952 | if (!ext4_empty_dir(inode)) |
| 2953 | goto end_rmdir; |
| 2954 | |
| 2955 | handle = ext4_journal_start(dir, EXT4_HT_DIR, |
| 2956 | EXT4_DATA_TRANS_BLOCKS(dir->i_sb)); |
| 2957 | if (IS_ERR(handle)) { |
| 2958 | retval = PTR_ERR(handle); |
| 2959 | handle = NULL; |
| 2960 | goto end_rmdir; |
| 2961 | } |
| 2962 | |
| 2963 | if (IS_DIRSYNC(dir)) |
| 2964 | ext4_handle_sync(handle); |
| 2965 | |
| 2966 | retval = ext4_delete_entry(handle, dir, de, bh); |
| 2967 | if (retval) |
| 2968 | goto end_rmdir; |
| 2969 | if (!EXT4_DIR_LINK_EMPTY(inode)) |
| 2970 | ext4_warning_inode(inode, |
| 2971 | "empty directory '%.*s' has too many links (%u)", |
| 2972 | dentry->d_name.len, dentry->d_name.name, |
| 2973 | inode->i_nlink); |
| 2974 | inode->i_version++; |
| 2975 | clear_nlink(inode); |
| 2976 | /* There's no need to set i_disksize: the fact that i_nlink is |
| 2977 | * zero will ensure that the right thing happens during any |
| 2978 | * recovery. */ |
| 2979 | inode->i_size = 0; |
| 2980 | ext4_orphan_add(handle, inode); |
| 2981 | inode->i_ctime = dir->i_ctime = dir->i_mtime = current_time(inode); |
| 2982 | ext4_mark_inode_dirty(handle, inode); |
| 2983 | ext4_dec_count(handle, dir); |
| 2984 | ext4_update_dx_flag(dir); |
| 2985 | ext4_mark_inode_dirty(handle, dir); |
| 2986 | |
| 2987 | end_rmdir: |
| 2988 | brelse(bh); |
| 2989 | if (handle) |
| 2990 | ext4_journal_stop(handle); |
| 2991 | return retval; |
| 2992 | } |
| 2993 | |
| 2994 | static int ext4_unlink(struct inode *dir, struct dentry *dentry) |
| 2995 | { |
| 2996 | int retval; |
| 2997 | struct inode *inode; |
| 2998 | struct buffer_head *bh; |
| 2999 | struct ext4_dir_entry_2 *de; |
| 3000 | handle_t *handle = NULL; |
| 3001 | |
| 3002 | if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) |
| 3003 | return -EIO; |
| 3004 | |
| 3005 | trace_ext4_unlink_enter(dir, dentry); |
| 3006 | /* Initialize quotas before so that eventual writes go |
| 3007 | * in separate transaction */ |
| 3008 | retval = dquot_initialize(dir); |
| 3009 | if (retval) |
| 3010 | return retval; |
| 3011 | retval = dquot_initialize(d_inode(dentry)); |
| 3012 | if (retval) |
| 3013 | return retval; |
| 3014 | |
| 3015 | retval = -ENOENT; |
| 3016 | bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); |
| 3017 | if (IS_ERR(bh)) |
| 3018 | return PTR_ERR(bh); |
| 3019 | if (!bh) |
| 3020 | goto end_unlink; |
| 3021 | |
| 3022 | inode = d_inode(dentry); |
| 3023 | |
| 3024 | retval = -EFSCORRUPTED; |
| 3025 | if (le32_to_cpu(de->inode) != inode->i_ino) |
| 3026 | goto end_unlink; |
| 3027 | |
| 3028 | handle = ext4_journal_start(dir, EXT4_HT_DIR, |
| 3029 | EXT4_DATA_TRANS_BLOCKS(dir->i_sb)); |
| 3030 | if (IS_ERR(handle)) { |
| 3031 | retval = PTR_ERR(handle); |
| 3032 | handle = NULL; |
| 3033 | goto end_unlink; |
| 3034 | } |
| 3035 | |
| 3036 | if (IS_DIRSYNC(dir)) |
| 3037 | ext4_handle_sync(handle); |
| 3038 | |
| 3039 | if (inode->i_nlink == 0) { |
| 3040 | ext4_warning_inode(inode, "Deleting file '%.*s' with no links", |
| 3041 | dentry->d_name.len, dentry->d_name.name); |
| 3042 | set_nlink(inode, 1); |
| 3043 | } |
| 3044 | retval = ext4_delete_entry(handle, dir, de, bh); |
| 3045 | if (retval) |
| 3046 | goto end_unlink; |
| 3047 | dir->i_ctime = dir->i_mtime = current_time(dir); |
| 3048 | ext4_update_dx_flag(dir); |
| 3049 | ext4_mark_inode_dirty(handle, dir); |
| 3050 | drop_nlink(inode); |
| 3051 | if (!inode->i_nlink) |
| 3052 | ext4_orphan_add(handle, inode); |
| 3053 | inode->i_ctime = current_time(inode); |
| 3054 | ext4_mark_inode_dirty(handle, inode); |
| 3055 | |
| 3056 | end_unlink: |
| 3057 | brelse(bh); |
| 3058 | if (handle) |
| 3059 | ext4_journal_stop(handle); |
| 3060 | trace_ext4_unlink_exit(dentry, retval); |
| 3061 | return retval; |
| 3062 | } |
| 3063 | |
| 3064 | static int ext4_symlink(struct inode *dir, |
| 3065 | struct dentry *dentry, const char *symname) |
| 3066 | { |
| 3067 | handle_t *handle; |
| 3068 | struct inode *inode; |
| 3069 | int err, len = strlen(symname); |
| 3070 | int credits; |
| 3071 | struct fscrypt_str disk_link; |
| 3072 | |
| 3073 | if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) |
| 3074 | return -EIO; |
| 3075 | |
| 3076 | err = fscrypt_prepare_symlink(dir, symname, len, dir->i_sb->s_blocksize, |
| 3077 | &disk_link); |
| 3078 | if (err) |
| 3079 | return err; |
| 3080 | |
| 3081 | err = dquot_initialize(dir); |
| 3082 | if (err) |
| 3083 | return err; |
| 3084 | |
| 3085 | if ((disk_link.len > EXT4_N_BLOCKS * 4)) { |
| 3086 | /* |
| 3087 | * For non-fast symlinks, we just allocate inode and put it on |
| 3088 | * orphan list in the first transaction => we need bitmap, |
| 3089 | * group descriptor, sb, inode block, quota blocks, and |
| 3090 | * possibly selinux xattr blocks. |
| 3091 | */ |
| 3092 | credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + |
| 3093 | EXT4_XATTR_TRANS_BLOCKS; |
| 3094 | } else { |
| 3095 | /* |
| 3096 | * Fast symlink. We have to add entry to directory |
| 3097 | * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS), |
| 3098 | * allocate new inode (bitmap, group descriptor, inode block, |
| 3099 | * quota blocks, sb is already counted in previous macros). |
| 3100 | */ |
| 3101 | credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + |
| 3102 | EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3; |
| 3103 | } |
| 3104 | |
| 3105 | inode = ext4_new_inode_start_handle(dir, S_IFLNK|S_IRWXUGO, |
| 3106 | &dentry->d_name, 0, NULL, |
| 3107 | EXT4_HT_DIR, credits); |
| 3108 | handle = ext4_journal_current_handle(); |
| 3109 | if (IS_ERR(inode)) { |
| 3110 | if (handle) |
| 3111 | ext4_journal_stop(handle); |
| 3112 | return PTR_ERR(inode); |
| 3113 | } |
| 3114 | |
| 3115 | if (IS_ENCRYPTED(inode)) { |
| 3116 | err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link); |
| 3117 | if (err) |
| 3118 | goto err_drop_inode; |
| 3119 | inode->i_op = &ext4_encrypted_symlink_inode_operations; |
| 3120 | } |
| 3121 | |
| 3122 | if ((disk_link.len > EXT4_N_BLOCKS * 4)) { |
| 3123 | if (!IS_ENCRYPTED(inode)) |
| 3124 | inode->i_op = &ext4_symlink_inode_operations; |
| 3125 | inode_nohighmem(inode); |
| 3126 | ext4_set_aops(inode); |
| 3127 | /* |
| 3128 | * We cannot call page_symlink() with transaction started |
| 3129 | * because it calls into ext4_write_begin() which can wait |
| 3130 | * for transaction commit if we are running out of space |
| 3131 | * and thus we deadlock. So we have to stop transaction now |
| 3132 | * and restart it when symlink contents is written. |
| 3133 | * |
| 3134 | * To keep fs consistent in case of crash, we have to put inode |
| 3135 | * to orphan list in the mean time. |
| 3136 | */ |
| 3137 | drop_nlink(inode); |
| 3138 | err = ext4_orphan_add(handle, inode); |
| 3139 | ext4_journal_stop(handle); |
| 3140 | handle = NULL; |
| 3141 | if (err) |
| 3142 | goto err_drop_inode; |
| 3143 | err = __page_symlink(inode, disk_link.name, disk_link.len, 1); |
| 3144 | if (err) |
| 3145 | goto err_drop_inode; |
| 3146 | /* |
| 3147 | * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS |
| 3148 | * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified |
| 3149 | */ |
| 3150 | handle = ext4_journal_start(dir, EXT4_HT_DIR, |
| 3151 | EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + |
| 3152 | EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1); |
| 3153 | if (IS_ERR(handle)) { |
| 3154 | err = PTR_ERR(handle); |
| 3155 | handle = NULL; |
| 3156 | goto err_drop_inode; |
| 3157 | } |
| 3158 | set_nlink(inode, 1); |
| 3159 | err = ext4_orphan_del(handle, inode); |
| 3160 | if (err) |
| 3161 | goto err_drop_inode; |
| 3162 | } else { |
| 3163 | /* clear the extent format for fast symlink */ |
| 3164 | ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS); |
| 3165 | if (!IS_ENCRYPTED(inode)) { |
| 3166 | inode->i_op = &ext4_fast_symlink_inode_operations; |
| 3167 | inode->i_link = (char *)&EXT4_I(inode)->i_data; |
| 3168 | } |
| 3169 | memcpy((char *)&EXT4_I(inode)->i_data, disk_link.name, |
| 3170 | disk_link.len); |
| 3171 | inode->i_size = disk_link.len - 1; |
| 3172 | } |
| 3173 | EXT4_I(inode)->i_disksize = inode->i_size; |
| 3174 | err = ext4_add_nondir(handle, dentry, inode); |
| 3175 | if (!err && IS_DIRSYNC(dir)) |
| 3176 | ext4_handle_sync(handle); |
| 3177 | |
| 3178 | if (handle) |
| 3179 | ext4_journal_stop(handle); |
| 3180 | goto out_free_encrypted_link; |
| 3181 | |
| 3182 | err_drop_inode: |
| 3183 | if (handle) |
| 3184 | ext4_journal_stop(handle); |
| 3185 | clear_nlink(inode); |
| 3186 | unlock_new_inode(inode); |
| 3187 | iput(inode); |
| 3188 | out_free_encrypted_link: |
| 3189 | if (disk_link.name != (unsigned char *)symname) |
| 3190 | kfree(disk_link.name); |
| 3191 | return err; |
| 3192 | } |
| 3193 | |
| 3194 | static int ext4_link(struct dentry *old_dentry, |
| 3195 | struct inode *dir, struct dentry *dentry) |
| 3196 | { |
| 3197 | handle_t *handle; |
| 3198 | struct inode *inode = d_inode(old_dentry); |
| 3199 | int err, retries = 0; |
| 3200 | |
| 3201 | if (inode->i_nlink >= EXT4_LINK_MAX) |
| 3202 | return -EMLINK; |
| 3203 | if (ext4_encrypted_inode(dir) && |
| 3204 | !fscrypt_has_permitted_context(dir, inode)) |
| 3205 | return -EPERM; |
| 3206 | |
| 3207 | if ((ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) && |
| 3208 | (!projid_eq(EXT4_I(dir)->i_projid, |
| 3209 | EXT4_I(old_dentry->d_inode)->i_projid))) |
| 3210 | return -EXDEV; |
| 3211 | |
| 3212 | err = dquot_initialize(dir); |
| 3213 | if (err) |
| 3214 | return err; |
| 3215 | |
| 3216 | retry: |
| 3217 | handle = ext4_journal_start(dir, EXT4_HT_DIR, |
| 3218 | (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + |
| 3219 | EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1); |
| 3220 | if (IS_ERR(handle)) |
| 3221 | return PTR_ERR(handle); |
| 3222 | |
| 3223 | if (IS_DIRSYNC(dir)) |
| 3224 | ext4_handle_sync(handle); |
| 3225 | |
| 3226 | inode->i_ctime = current_time(inode); |
| 3227 | ext4_inc_count(handle, inode); |
| 3228 | ihold(inode); |
| 3229 | |
| 3230 | err = ext4_add_entry(handle, dentry, inode); |
| 3231 | if (!err) { |
| 3232 | ext4_mark_inode_dirty(handle, inode); |
| 3233 | /* this can happen only for tmpfile being |
| 3234 | * linked the first time |
| 3235 | */ |
| 3236 | if (inode->i_nlink == 1) |
| 3237 | ext4_orphan_del(handle, inode); |
| 3238 | d_instantiate(dentry, inode); |
| 3239 | } else { |
| 3240 | drop_nlink(inode); |
| 3241 | iput(inode); |
| 3242 | } |
| 3243 | ext4_journal_stop(handle); |
| 3244 | if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) |
| 3245 | goto retry; |
| 3246 | return err; |
| 3247 | } |
| 3248 | |
| 3249 | |
| 3250 | /* |
| 3251 | * Try to find buffer head where contains the parent block. |
| 3252 | * It should be the inode block if it is inlined or the 1st block |
| 3253 | * if it is a normal dir. |
| 3254 | */ |
| 3255 | static struct buffer_head *ext4_get_first_dir_block(handle_t *handle, |
| 3256 | struct inode *inode, |
| 3257 | int *retval, |
| 3258 | struct ext4_dir_entry_2 **parent_de, |
| 3259 | int *inlined) |
| 3260 | { |
| 3261 | struct buffer_head *bh; |
| 3262 | |
| 3263 | if (!ext4_has_inline_data(inode)) { |
| 3264 | bh = ext4_read_dirblock(inode, 0, EITHER); |
| 3265 | if (IS_ERR(bh)) { |
| 3266 | *retval = PTR_ERR(bh); |
| 3267 | return NULL; |
| 3268 | } |
| 3269 | *parent_de = ext4_next_entry( |
| 3270 | (struct ext4_dir_entry_2 *)bh->b_data, |
| 3271 | inode->i_sb->s_blocksize); |
| 3272 | return bh; |
| 3273 | } |
| 3274 | |
| 3275 | *inlined = 1; |
| 3276 | return ext4_get_first_inline_block(inode, parent_de, retval); |
| 3277 | } |
| 3278 | |
| 3279 | struct ext4_renament { |
| 3280 | struct inode *dir; |
| 3281 | struct dentry *dentry; |
| 3282 | struct inode *inode; |
| 3283 | bool is_dir; |
| 3284 | int dir_nlink_delta; |
| 3285 | |
| 3286 | /* entry for "dentry" */ |
| 3287 | struct buffer_head *bh; |
| 3288 | struct ext4_dir_entry_2 *de; |
| 3289 | int inlined; |
| 3290 | |
| 3291 | /* entry for ".." in inode if it's a directory */ |
| 3292 | struct buffer_head *dir_bh; |
| 3293 | struct ext4_dir_entry_2 *parent_de; |
| 3294 | int dir_inlined; |
| 3295 | }; |
| 3296 | |
| 3297 | static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent) |
| 3298 | { |
| 3299 | int retval; |
| 3300 | |
| 3301 | ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode, |
| 3302 | &retval, &ent->parent_de, |
| 3303 | &ent->dir_inlined); |
| 3304 | if (!ent->dir_bh) |
| 3305 | return retval; |
| 3306 | if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino) |
| 3307 | return -EFSCORRUPTED; |
| 3308 | BUFFER_TRACE(ent->dir_bh, "get_write_access"); |
| 3309 | return ext4_journal_get_write_access(handle, ent->dir_bh); |
| 3310 | } |
| 3311 | |
| 3312 | static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent, |
| 3313 | unsigned dir_ino) |
| 3314 | { |
| 3315 | int retval; |
| 3316 | |
| 3317 | ent->parent_de->inode = cpu_to_le32(dir_ino); |
| 3318 | BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata"); |
| 3319 | if (!ent->dir_inlined) { |
| 3320 | if (is_dx(ent->inode)) { |
| 3321 | retval = ext4_handle_dirty_dx_node(handle, |
| 3322 | ent->inode, |
| 3323 | ent->dir_bh); |
| 3324 | } else { |
| 3325 | retval = ext4_handle_dirty_dirent_node(handle, |
| 3326 | ent->inode, |
| 3327 | ent->dir_bh); |
| 3328 | } |
| 3329 | } else { |
| 3330 | retval = ext4_mark_inode_dirty(handle, ent->inode); |
| 3331 | } |
| 3332 | if (retval) { |
| 3333 | ext4_std_error(ent->dir->i_sb, retval); |
| 3334 | return retval; |
| 3335 | } |
| 3336 | return 0; |
| 3337 | } |
| 3338 | |
| 3339 | static int ext4_setent(handle_t *handle, struct ext4_renament *ent, |
| 3340 | unsigned ino, unsigned file_type) |
| 3341 | { |
| 3342 | int retval; |
| 3343 | |
| 3344 | BUFFER_TRACE(ent->bh, "get write access"); |
| 3345 | retval = ext4_journal_get_write_access(handle, ent->bh); |
| 3346 | if (retval) |
| 3347 | return retval; |
| 3348 | ent->de->inode = cpu_to_le32(ino); |
| 3349 | if (ext4_has_feature_filetype(ent->dir->i_sb)) |
| 3350 | ent->de->file_type = file_type; |
| 3351 | ent->dir->i_version++; |
| 3352 | ent->dir->i_ctime = ent->dir->i_mtime = |
| 3353 | current_time(ent->dir); |
| 3354 | ext4_mark_inode_dirty(handle, ent->dir); |
| 3355 | BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata"); |
| 3356 | if (!ent->inlined) { |
| 3357 | retval = ext4_handle_dirty_dirent_node(handle, |
| 3358 | ent->dir, ent->bh); |
| 3359 | if (unlikely(retval)) { |
| 3360 | ext4_std_error(ent->dir->i_sb, retval); |
| 3361 | return retval; |
| 3362 | } |
| 3363 | } |
| 3364 | brelse(ent->bh); |
| 3365 | ent->bh = NULL; |
| 3366 | |
| 3367 | return 0; |
| 3368 | } |
| 3369 | |
| 3370 | static int ext4_find_delete_entry(handle_t *handle, struct inode *dir, |
| 3371 | const struct qstr *d_name) |
| 3372 | { |
| 3373 | int retval = -ENOENT; |
| 3374 | struct buffer_head *bh; |
| 3375 | struct ext4_dir_entry_2 *de; |
| 3376 | |
| 3377 | bh = ext4_find_entry(dir, d_name, &de, NULL); |
| 3378 | if (IS_ERR(bh)) |
| 3379 | return PTR_ERR(bh); |
| 3380 | if (bh) { |
| 3381 | retval = ext4_delete_entry(handle, dir, de, bh); |
| 3382 | brelse(bh); |
| 3383 | } |
| 3384 | return retval; |
| 3385 | } |
| 3386 | |
| 3387 | static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent, |
| 3388 | int force_reread) |
| 3389 | { |
| 3390 | int retval; |
| 3391 | /* |
| 3392 | * ent->de could have moved from under us during htree split, so make |
| 3393 | * sure that we are deleting the right entry. We might also be pointing |
| 3394 | * to a stale entry in the unused part of ent->bh so just checking inum |
| 3395 | * and the name isn't enough. |
| 3396 | */ |
| 3397 | if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino || |
| 3398 | ent->de->name_len != ent->dentry->d_name.len || |
| 3399 | strncmp(ent->de->name, ent->dentry->d_name.name, |
| 3400 | ent->de->name_len) || |
| 3401 | force_reread) { |
| 3402 | retval = ext4_find_delete_entry(handle, ent->dir, |
| 3403 | &ent->dentry->d_name); |
| 3404 | } else { |
| 3405 | retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh); |
| 3406 | if (retval == -ENOENT) { |
| 3407 | retval = ext4_find_delete_entry(handle, ent->dir, |
| 3408 | &ent->dentry->d_name); |
| 3409 | } |
| 3410 | } |
| 3411 | |
| 3412 | if (retval) { |
| 3413 | ext4_warning_inode(ent->dir, |
| 3414 | "Deleting old file: nlink %d, error=%d", |
| 3415 | ent->dir->i_nlink, retval); |
| 3416 | } |
| 3417 | } |
| 3418 | |
| 3419 | static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent) |
| 3420 | { |
| 3421 | if (ent->dir_nlink_delta) { |
| 3422 | if (ent->dir_nlink_delta == -1) |
| 3423 | ext4_dec_count(handle, ent->dir); |
| 3424 | else |
| 3425 | ext4_inc_count(handle, ent->dir); |
| 3426 | ext4_mark_inode_dirty(handle, ent->dir); |
| 3427 | } |
| 3428 | } |
| 3429 | |
| 3430 | static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent, |
| 3431 | int credits, handle_t **h) |
| 3432 | { |
| 3433 | struct inode *wh; |
| 3434 | handle_t *handle; |
| 3435 | int retries = 0; |
| 3436 | |
| 3437 | /* |
| 3438 | * for inode block, sb block, group summaries, |
| 3439 | * and inode bitmap |
| 3440 | */ |
| 3441 | credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) + |
| 3442 | EXT4_XATTR_TRANS_BLOCKS + 4); |
| 3443 | retry: |
| 3444 | wh = ext4_new_inode_start_handle(ent->dir, S_IFCHR | WHITEOUT_MODE, |
| 3445 | &ent->dentry->d_name, 0, NULL, |
| 3446 | EXT4_HT_DIR, credits); |
| 3447 | |
| 3448 | handle = ext4_journal_current_handle(); |
| 3449 | if (IS_ERR(wh)) { |
| 3450 | if (handle) |
| 3451 | ext4_journal_stop(handle); |
| 3452 | if (PTR_ERR(wh) == -ENOSPC && |
| 3453 | ext4_should_retry_alloc(ent->dir->i_sb, &retries)) |
| 3454 | goto retry; |
| 3455 | } else { |
| 3456 | *h = handle; |
| 3457 | init_special_inode(wh, wh->i_mode, WHITEOUT_DEV); |
| 3458 | wh->i_op = &ext4_special_inode_operations; |
| 3459 | } |
| 3460 | return wh; |
| 3461 | } |
| 3462 | |
| 3463 | /* |
| 3464 | * Anybody can rename anything with this: the permission checks are left to the |
| 3465 | * higher-level routines. |
| 3466 | * |
| 3467 | * n.b. old_{dentry,inode) refers to the source dentry/inode |
| 3468 | * while new_{dentry,inode) refers to the destination dentry/inode |
| 3469 | * This comes from rename(const char *oldpath, const char *newpath) |
| 3470 | */ |
| 3471 | static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, |
| 3472 | struct inode *new_dir, struct dentry *new_dentry, |
| 3473 | unsigned int flags) |
| 3474 | { |
| 3475 | handle_t *handle = NULL; |
| 3476 | struct ext4_renament old = { |
| 3477 | .dir = old_dir, |
| 3478 | .dentry = old_dentry, |
| 3479 | .inode = d_inode(old_dentry), |
| 3480 | }; |
| 3481 | struct ext4_renament new = { |
| 3482 | .dir = new_dir, |
| 3483 | .dentry = new_dentry, |
| 3484 | .inode = d_inode(new_dentry), |
| 3485 | }; |
| 3486 | int force_reread; |
| 3487 | int retval; |
| 3488 | struct inode *whiteout = NULL; |
| 3489 | int credits; |
| 3490 | u8 old_file_type; |
| 3491 | |
| 3492 | if (new.inode && new.inode->i_nlink == 0) { |
| 3493 | EXT4_ERROR_INODE(new.inode, |
| 3494 | "target of rename is already freed"); |
| 3495 | return -EFSCORRUPTED; |
| 3496 | } |
| 3497 | |
| 3498 | if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT)) && |
| 3499 | (!projid_eq(EXT4_I(new_dir)->i_projid, |
| 3500 | EXT4_I(old_dentry->d_inode)->i_projid))) |
| 3501 | return -EXDEV; |
| 3502 | |
| 3503 | if ((ext4_encrypted_inode(old_dir) && |
| 3504 | !fscrypt_has_encryption_key(old_dir)) || |
| 3505 | (ext4_encrypted_inode(new_dir) && |
| 3506 | !fscrypt_has_encryption_key(new_dir))) |
| 3507 | return -ENOKEY; |
| 3508 | |
| 3509 | retval = dquot_initialize(old.dir); |
| 3510 | if (retval) |
| 3511 | return retval; |
| 3512 | retval = dquot_initialize(new.dir); |
| 3513 | if (retval) |
| 3514 | return retval; |
| 3515 | |
| 3516 | /* Initialize quotas before so that eventual writes go |
| 3517 | * in separate transaction */ |
| 3518 | if (new.inode) { |
| 3519 | retval = dquot_initialize(new.inode); |
| 3520 | if (retval) |
| 3521 | return retval; |
| 3522 | } |
| 3523 | |
| 3524 | old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL); |
| 3525 | if (IS_ERR(old.bh)) |
| 3526 | return PTR_ERR(old.bh); |
| 3527 | /* |
| 3528 | * Check for inode number is _not_ due to possible IO errors. |
| 3529 | * We might rmdir the source, keep it as pwd of some process |
| 3530 | * and merrily kill the link to whatever was created under the |
| 3531 | * same name. Goodbye sticky bit ;-< |
| 3532 | */ |
| 3533 | retval = -ENOENT; |
| 3534 | if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) |
| 3535 | goto end_rename; |
| 3536 | |
| 3537 | if ((old.dir != new.dir) && |
| 3538 | ext4_encrypted_inode(new.dir) && |
| 3539 | !fscrypt_has_permitted_context(new.dir, old.inode)) { |
| 3540 | retval = -EPERM; |
| 3541 | goto end_rename; |
| 3542 | } |
| 3543 | |
| 3544 | new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, |
| 3545 | &new.de, &new.inlined); |
| 3546 | if (IS_ERR(new.bh)) { |
| 3547 | retval = PTR_ERR(new.bh); |
| 3548 | new.bh = NULL; |
| 3549 | goto end_rename; |
| 3550 | } |
| 3551 | if (new.bh) { |
| 3552 | if (!new.inode) { |
| 3553 | brelse(new.bh); |
| 3554 | new.bh = NULL; |
| 3555 | } |
| 3556 | } |
| 3557 | if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC)) |
| 3558 | ext4_alloc_da_blocks(old.inode); |
| 3559 | |
| 3560 | credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + |
| 3561 | EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2); |
| 3562 | if (!(flags & RENAME_WHITEOUT)) { |
| 3563 | handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits); |
| 3564 | if (IS_ERR(handle)) { |
| 3565 | retval = PTR_ERR(handle); |
| 3566 | handle = NULL; |
| 3567 | goto end_rename; |
| 3568 | } |
| 3569 | } else { |
| 3570 | whiteout = ext4_whiteout_for_rename(&old, credits, &handle); |
| 3571 | if (IS_ERR(whiteout)) { |
| 3572 | retval = PTR_ERR(whiteout); |
| 3573 | whiteout = NULL; |
| 3574 | goto end_rename; |
| 3575 | } |
| 3576 | } |
| 3577 | |
| 3578 | if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) |
| 3579 | ext4_handle_sync(handle); |
| 3580 | |
| 3581 | if (S_ISDIR(old.inode->i_mode)) { |
| 3582 | if (new.inode) { |
| 3583 | retval = -ENOTEMPTY; |
| 3584 | if (!ext4_empty_dir(new.inode)) |
| 3585 | goto end_rename; |
| 3586 | } else { |
| 3587 | retval = -EMLINK; |
| 3588 | if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir)) |
| 3589 | goto end_rename; |
| 3590 | } |
| 3591 | retval = ext4_rename_dir_prepare(handle, &old); |
| 3592 | if (retval) |
| 3593 | goto end_rename; |
| 3594 | } |
| 3595 | /* |
| 3596 | * If we're renaming a file within an inline_data dir and adding or |
| 3597 | * setting the new dirent causes a conversion from inline_data to |
| 3598 | * extents/blockmap, we need to force the dirent delete code to |
| 3599 | * re-read the directory, or else we end up trying to delete a dirent |
| 3600 | * from what is now the extent tree root (or a block map). |
| 3601 | */ |
| 3602 | force_reread = (new.dir->i_ino == old.dir->i_ino && |
| 3603 | ext4_test_inode_flag(new.dir, EXT4_INODE_INLINE_DATA)); |
| 3604 | |
| 3605 | old_file_type = old.de->file_type; |
| 3606 | if (whiteout) { |
| 3607 | /* |
| 3608 | * Do this before adding a new entry, so the old entry is sure |
| 3609 | * to be still pointing to the valid old entry. |
| 3610 | */ |
| 3611 | retval = ext4_setent(handle, &old, whiteout->i_ino, |
| 3612 | EXT4_FT_CHRDEV); |
| 3613 | if (retval) |
| 3614 | goto end_rename; |
| 3615 | ext4_mark_inode_dirty(handle, whiteout); |
| 3616 | } |
| 3617 | if (!new.bh) { |
| 3618 | retval = ext4_add_entry(handle, new.dentry, old.inode); |
| 3619 | if (retval) |
| 3620 | goto end_rename; |
| 3621 | } else { |
| 3622 | retval = ext4_setent(handle, &new, |
| 3623 | old.inode->i_ino, old_file_type); |
| 3624 | if (retval) |
| 3625 | goto end_rename; |
| 3626 | } |
| 3627 | if (force_reread) |
| 3628 | force_reread = !ext4_test_inode_flag(new.dir, |
| 3629 | EXT4_INODE_INLINE_DATA); |
| 3630 | |
| 3631 | /* |
| 3632 | * Like most other Unix systems, set the ctime for inodes on a |
| 3633 | * rename. |
| 3634 | */ |
| 3635 | old.inode->i_ctime = current_time(old.inode); |
| 3636 | ext4_mark_inode_dirty(handle, old.inode); |
| 3637 | |
| 3638 | if (!whiteout) { |
| 3639 | /* |
| 3640 | * ok, that's it |
| 3641 | */ |
| 3642 | ext4_rename_delete(handle, &old, force_reread); |
| 3643 | } |
| 3644 | |
| 3645 | if (new.inode) { |
| 3646 | ext4_dec_count(handle, new.inode); |
| 3647 | new.inode->i_ctime = current_time(new.inode); |
| 3648 | } |
| 3649 | old.dir->i_ctime = old.dir->i_mtime = current_time(old.dir); |
| 3650 | ext4_update_dx_flag(old.dir); |
| 3651 | if (old.dir_bh) { |
| 3652 | retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); |
| 3653 | if (retval) |
| 3654 | goto end_rename; |
| 3655 | |
| 3656 | ext4_dec_count(handle, old.dir); |
| 3657 | if (new.inode) { |
| 3658 | /* checked ext4_empty_dir above, can't have another |
| 3659 | * parent, ext4_dec_count() won't work for many-linked |
| 3660 | * dirs */ |
| 3661 | clear_nlink(new.inode); |
| 3662 | } else { |
| 3663 | ext4_inc_count(handle, new.dir); |
| 3664 | ext4_update_dx_flag(new.dir); |
| 3665 | ext4_mark_inode_dirty(handle, new.dir); |
| 3666 | } |
| 3667 | } |
| 3668 | ext4_mark_inode_dirty(handle, old.dir); |
| 3669 | if (new.inode) { |
| 3670 | ext4_mark_inode_dirty(handle, new.inode); |
| 3671 | if (!new.inode->i_nlink) |
| 3672 | ext4_orphan_add(handle, new.inode); |
| 3673 | } |
| 3674 | retval = 0; |
| 3675 | |
| 3676 | end_rename: |
| 3677 | brelse(old.dir_bh); |
| 3678 | brelse(old.bh); |
| 3679 | brelse(new.bh); |
| 3680 | if (whiteout) { |
| 3681 | if (retval) |
| 3682 | drop_nlink(whiteout); |
| 3683 | unlock_new_inode(whiteout); |
| 3684 | iput(whiteout); |
| 3685 | } |
| 3686 | if (handle) |
| 3687 | ext4_journal_stop(handle); |
| 3688 | return retval; |
| 3689 | } |
| 3690 | |
| 3691 | static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry, |
| 3692 | struct inode *new_dir, struct dentry *new_dentry) |
| 3693 | { |
| 3694 | handle_t *handle = NULL; |
| 3695 | struct ext4_renament old = { |
| 3696 | .dir = old_dir, |
| 3697 | .dentry = old_dentry, |
| 3698 | .inode = d_inode(old_dentry), |
| 3699 | }; |
| 3700 | struct ext4_renament new = { |
| 3701 | .dir = new_dir, |
| 3702 | .dentry = new_dentry, |
| 3703 | .inode = d_inode(new_dentry), |
| 3704 | }; |
| 3705 | u8 new_file_type; |
| 3706 | int retval; |
| 3707 | struct timespec ctime; |
| 3708 | |
| 3709 | if ((ext4_encrypted_inode(old_dir) && |
| 3710 | !fscrypt_has_encryption_key(old_dir)) || |
| 3711 | (ext4_encrypted_inode(new_dir) && |
| 3712 | !fscrypt_has_encryption_key(new_dir))) |
| 3713 | return -ENOKEY; |
| 3714 | |
| 3715 | if ((ext4_encrypted_inode(old_dir) || |
| 3716 | ext4_encrypted_inode(new_dir)) && |
| 3717 | (old_dir != new_dir) && |
| 3718 | (!fscrypt_has_permitted_context(new_dir, old.inode) || |
| 3719 | !fscrypt_has_permitted_context(old_dir, new.inode))) |
| 3720 | return -EPERM; |
| 3721 | |
| 3722 | if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT) && |
| 3723 | !projid_eq(EXT4_I(new_dir)->i_projid, |
| 3724 | EXT4_I(old_dentry->d_inode)->i_projid)) || |
| 3725 | (ext4_test_inode_flag(old_dir, EXT4_INODE_PROJINHERIT) && |
| 3726 | !projid_eq(EXT4_I(old_dir)->i_projid, |
| 3727 | EXT4_I(new_dentry->d_inode)->i_projid))) |
| 3728 | return -EXDEV; |
| 3729 | |
| 3730 | retval = dquot_initialize(old.dir); |
| 3731 | if (retval) |
| 3732 | return retval; |
| 3733 | retval = dquot_initialize(new.dir); |
| 3734 | if (retval) |
| 3735 | return retval; |
| 3736 | |
| 3737 | old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, |
| 3738 | &old.de, &old.inlined); |
| 3739 | if (IS_ERR(old.bh)) |
| 3740 | return PTR_ERR(old.bh); |
| 3741 | /* |
| 3742 | * Check for inode number is _not_ due to possible IO errors. |
| 3743 | * We might rmdir the source, keep it as pwd of some process |
| 3744 | * and merrily kill the link to whatever was created under the |
| 3745 | * same name. Goodbye sticky bit ;-< |
| 3746 | */ |
| 3747 | retval = -ENOENT; |
| 3748 | if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) |
| 3749 | goto end_rename; |
| 3750 | |
| 3751 | new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, |
| 3752 | &new.de, &new.inlined); |
| 3753 | if (IS_ERR(new.bh)) { |
| 3754 | retval = PTR_ERR(new.bh); |
| 3755 | new.bh = NULL; |
| 3756 | goto end_rename; |
| 3757 | } |
| 3758 | |
| 3759 | /* RENAME_EXCHANGE case: old *and* new must both exist */ |
| 3760 | if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino) |
| 3761 | goto end_rename; |
| 3762 | |
| 3763 | handle = ext4_journal_start(old.dir, EXT4_HT_DIR, |
| 3764 | (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + |
| 3765 | 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2)); |
| 3766 | if (IS_ERR(handle)) { |
| 3767 | retval = PTR_ERR(handle); |
| 3768 | handle = NULL; |
| 3769 | goto end_rename; |
| 3770 | } |
| 3771 | |
| 3772 | if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) |
| 3773 | ext4_handle_sync(handle); |
| 3774 | |
| 3775 | if (S_ISDIR(old.inode->i_mode)) { |
| 3776 | old.is_dir = true; |
| 3777 | retval = ext4_rename_dir_prepare(handle, &old); |
| 3778 | if (retval) |
| 3779 | goto end_rename; |
| 3780 | } |
| 3781 | if (S_ISDIR(new.inode->i_mode)) { |
| 3782 | new.is_dir = true; |
| 3783 | retval = ext4_rename_dir_prepare(handle, &new); |
| 3784 | if (retval) |
| 3785 | goto end_rename; |
| 3786 | } |
| 3787 | |
| 3788 | /* |
| 3789 | * Other than the special case of overwriting a directory, parents' |
| 3790 | * nlink only needs to be modified if this is a cross directory rename. |
| 3791 | */ |
| 3792 | if (old.dir != new.dir && old.is_dir != new.is_dir) { |
| 3793 | old.dir_nlink_delta = old.is_dir ? -1 : 1; |
| 3794 | new.dir_nlink_delta = -old.dir_nlink_delta; |
| 3795 | retval = -EMLINK; |
| 3796 | if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) || |
| 3797 | (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir))) |
| 3798 | goto end_rename; |
| 3799 | } |
| 3800 | |
| 3801 | new_file_type = new.de->file_type; |
| 3802 | retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type); |
| 3803 | if (retval) |
| 3804 | goto end_rename; |
| 3805 | |
| 3806 | retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type); |
| 3807 | if (retval) |
| 3808 | goto end_rename; |
| 3809 | |
| 3810 | /* |
| 3811 | * Like most other Unix systems, set the ctime for inodes on a |
| 3812 | * rename. |
| 3813 | */ |
| 3814 | ctime = current_time(old.inode); |
| 3815 | old.inode->i_ctime = ctime; |
| 3816 | new.inode->i_ctime = ctime; |
| 3817 | ext4_mark_inode_dirty(handle, old.inode); |
| 3818 | ext4_mark_inode_dirty(handle, new.inode); |
| 3819 | |
| 3820 | if (old.dir_bh) { |
| 3821 | retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); |
| 3822 | if (retval) |
| 3823 | goto end_rename; |
| 3824 | } |
| 3825 | if (new.dir_bh) { |
| 3826 | retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino); |
| 3827 | if (retval) |
| 3828 | goto end_rename; |
| 3829 | } |
| 3830 | ext4_update_dir_count(handle, &old); |
| 3831 | ext4_update_dir_count(handle, &new); |
| 3832 | retval = 0; |
| 3833 | |
| 3834 | end_rename: |
| 3835 | brelse(old.dir_bh); |
| 3836 | brelse(new.dir_bh); |
| 3837 | brelse(old.bh); |
| 3838 | brelse(new.bh); |
| 3839 | if (handle) |
| 3840 | ext4_journal_stop(handle); |
| 3841 | return retval; |
| 3842 | } |
| 3843 | |
| 3844 | static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry, |
| 3845 | struct inode *new_dir, struct dentry *new_dentry, |
| 3846 | unsigned int flags) |
| 3847 | { |
| 3848 | if (unlikely(ext4_forced_shutdown(EXT4_SB(old_dir->i_sb)))) |
| 3849 | return -EIO; |
| 3850 | |
| 3851 | if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) |
| 3852 | return -EINVAL; |
| 3853 | |
| 3854 | if (flags & RENAME_EXCHANGE) { |
| 3855 | return ext4_cross_rename(old_dir, old_dentry, |
| 3856 | new_dir, new_dentry); |
| 3857 | } |
| 3858 | |
| 3859 | return ext4_rename(old_dir, old_dentry, new_dir, new_dentry, flags); |
| 3860 | } |
| 3861 | |
| 3862 | /* |
| 3863 | * directories can handle most operations... |
| 3864 | */ |
| 3865 | const struct inode_operations ext4_dir_inode_operations = { |
| 3866 | .create = ext4_create, |
| 3867 | .lookup = ext4_lookup, |
| 3868 | .link = ext4_link, |
| 3869 | .unlink = ext4_unlink, |
| 3870 | .symlink = ext4_symlink, |
| 3871 | .mkdir = ext4_mkdir, |
| 3872 | .rmdir = ext4_rmdir, |
| 3873 | .mknod = ext4_mknod, |
| 3874 | .tmpfile = ext4_tmpfile, |
| 3875 | .rename = ext4_rename2, |
| 3876 | .setattr = ext4_setattr, |
| 3877 | .getattr = ext4_getattr, |
| 3878 | .listxattr = ext4_listxattr, |
| 3879 | .get_acl = ext4_get_acl, |
| 3880 | .set_acl = ext4_set_acl, |
| 3881 | .fiemap = ext4_fiemap, |
| 3882 | }; |
| 3883 | |
| 3884 | const struct inode_operations ext4_special_inode_operations = { |
| 3885 | .setattr = ext4_setattr, |
| 3886 | .getattr = ext4_getattr, |
| 3887 | .listxattr = ext4_listxattr, |
| 3888 | .get_acl = ext4_get_acl, |
| 3889 | .set_acl = ext4_set_acl, |
| 3890 | }; |