1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) STRATO AG 2011. All rights reserved. 4 */ 5 6 /* 7 * This module can be used to catch cases when the btrfs kernel 8 * code executes write requests to the disk that bring the file 9 * system in an inconsistent state. In such a state, a power-loss 10 * or kernel panic event would cause that the data on disk is 11 * lost or at least damaged. 12 * 13 * Code is added that examines all block write requests during 14 * runtime (including writes of the super block). Three rules 15 * are verified and an error is printed on violation of the 16 * rules: 17 * 1. It is not allowed to write a disk block which is 18 * currently referenced by the super block (either directly 19 * or indirectly). 20 * 2. When a super block is written, it is verified that all 21 * referenced (directly or indirectly) blocks fulfill the 22 * following requirements: 23 * 2a. All referenced blocks have either been present when 24 * the file system was mounted, (i.e., they have been 25 * referenced by the super block) or they have been 26 * written since then and the write completion callback 27 * was called and no write error was indicated and a 28 * FLUSH request to the device where these blocks are 29 * located was received and completed. 30 * 2b. All referenced blocks need to have a generation 31 * number which is equal to the parent's number. 32 * 33 * One issue that was found using this module was that the log 34 * tree on disk became temporarily corrupted because disk blocks 35 * that had been in use for the log tree had been freed and 36 * reused too early, while being referenced by the written super 37 * block. 38 * 39 * The search term in the kernel log that can be used to filter 40 * on the existence of detected integrity issues is 41 * "btrfs: attempt". 42 * 43 * The integrity check is enabled via mount options. These 44 * mount options are only supported if the integrity check 45 * tool is compiled by defining BTRFS_FS_CHECK_INTEGRITY. 46 * 47 * Example #1, apply integrity checks to all metadata: 48 * mount /dev/sdb1 /mnt -o check_int 49 * 50 * Example #2, apply integrity checks to all metadata and 51 * to data extents: 52 * mount /dev/sdb1 /mnt -o check_int_data 53 * 54 * Example #3, apply integrity checks to all metadata and dump 55 * the tree that the super block references to kernel messages 56 * each time after a super block was written: 57 * mount /dev/sdb1 /mnt -o check_int,check_int_print_mask=263 58 * 59 * If the integrity check tool is included and activated in 60 * the mount options, plenty of kernel memory is used, and 61 * plenty of additional CPU cycles are spent. Enabling this 62 * functionality is not intended for normal use. In most 63 * cases, unless you are a btrfs developer who needs to verify 64 * the integrity of (super)-block write requests, do not 65 * enable the config option BTRFS_FS_CHECK_INTEGRITY to 66 * include and compile the integrity check tool. 67 * 68 * Expect millions of lines of information in the kernel log with an 69 * enabled check_int_print_mask. Therefore set LOG_BUF_SHIFT in the 70 * kernel config to at least 26 (which is 64MB). Usually the value is 71 * limited to 21 (which is 2MB) in init/Kconfig. The file needs to be 72 * changed like this before LOG_BUF_SHIFT can be set to a high value: 73 * config LOG_BUF_SHIFT 74 * int "Kernel log buffer size (16 => 64KB, 17 => 128KB)" 75 * range 12 30 76 */ 77 78 #include <linux/sched.h> 79 #include <linux/slab.h> 80 #include <linux/mutex.h> 81 #include <linux/blkdev.h> 82 #include <linux/mm.h> 83 #include <linux/string.h> 84 #include <crypto/hash.h> 85 #include "messages.h" 86 #include "ctree.h" 87 #include "disk-io.h" 88 #include "transaction.h" 89 #include "extent_io.h" 90 #include "volumes.h" 91 #include "print-tree.h" 92 #include "locking.h" 93 #include "check-integrity.h" 94 #include "rcu-string.h" 95 #include "compression.h" 96 #include "accessors.h" 97 98 #define BTRFSIC_BLOCK_HASHTABLE_SIZE 0x10000 99 #define BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE 0x10000 100 #define BTRFSIC_DEV2STATE_HASHTABLE_SIZE 0x100 101 #define BTRFSIC_BLOCK_MAGIC_NUMBER 0x14491051 102 #define BTRFSIC_BLOCK_LINK_MAGIC_NUMBER 0x11070807 103 #define BTRFSIC_DEV2STATE_MAGIC_NUMBER 0x20111530 104 #define BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER 20111300 105 #define BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL (200 - 6) /* in characters, 106 * excluding " [...]" */ 107 #define BTRFSIC_GENERATION_UNKNOWN ((u64)-1) 108 109 /* 110 * The definition of the bitmask fields for the print_mask. 111 * They are specified with the mount option check_integrity_print_mask. 112 */ 113 #define BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE 0x00000001 114 #define BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION 0x00000002 115 #define BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE 0x00000004 116 #define BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE 0x00000008 117 #define BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH 0x00000010 118 #define BTRFSIC_PRINT_MASK_END_IO_BIO_BH 0x00000020 119 #define BTRFSIC_PRINT_MASK_VERBOSE 0x00000040 120 #define BTRFSIC_PRINT_MASK_VERY_VERBOSE 0x00000080 121 #define BTRFSIC_PRINT_MASK_INITIAL_TREE 0x00000100 122 #define BTRFSIC_PRINT_MASK_INITIAL_ALL_TREES 0x00000200 123 #define BTRFSIC_PRINT_MASK_INITIAL_DATABASE 0x00000400 124 #define BTRFSIC_PRINT_MASK_NUM_COPIES 0x00000800 125 #define BTRFSIC_PRINT_MASK_TREE_WITH_ALL_MIRRORS 0x00001000 126 #define BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE 0x00002000 127 128 struct btrfsic_dev_state; 129 struct btrfsic_state; 130 131 struct btrfsic_block { 132 u32 magic_num; /* only used for debug purposes */ 133 unsigned int is_metadata:1; /* if it is meta-data, not data-data */ 134 unsigned int is_superblock:1; /* if it is one of the superblocks */ 135 unsigned int is_iodone:1; /* if is done by lower subsystem */ 136 unsigned int iodone_w_error:1; /* error was indicated to endio */ 137 unsigned int never_written:1; /* block was added because it was 138 * referenced, not because it was 139 * written */ 140 unsigned int mirror_num; /* large enough to hold 141 * BTRFS_SUPER_MIRROR_MAX */ 142 struct btrfsic_dev_state *dev_state; 143 u64 dev_bytenr; /* key, physical byte num on disk */ 144 u64 logical_bytenr; /* logical byte num on disk */ 145 u64 generation; 146 struct btrfs_disk_key disk_key; /* extra info to print in case of 147 * issues, will not always be correct */ 148 struct list_head collision_resolving_node; /* list node */ 149 struct list_head all_blocks_node; /* list node */ 150 151 /* the following two lists contain block_link items */ 152 struct list_head ref_to_list; /* list */ 153 struct list_head ref_from_list; /* list */ 154 struct btrfsic_block *next_in_same_bio; 155 void *orig_bio_private; 156 bio_end_io_t *orig_bio_end_io; 157 blk_opf_t submit_bio_bh_rw; 158 u64 flush_gen; /* only valid if !never_written */ 159 }; 160 161 /* 162 * Elements of this type are allocated dynamically and required because 163 * each block object can refer to and can be ref from multiple blocks. 164 * The key to lookup them in the hashtable is the dev_bytenr of 165 * the block ref to plus the one from the block referred from. 166 * The fact that they are searchable via a hashtable and that a 167 * ref_cnt is maintained is not required for the btrfs integrity 168 * check algorithm itself, it is only used to make the output more 169 * beautiful in case that an error is detected (an error is defined 170 * as a write operation to a block while that block is still referenced). 171 */ 172 struct btrfsic_block_link { 173 u32 magic_num; /* only used for debug purposes */ 174 u32 ref_cnt; 175 struct list_head node_ref_to; /* list node */ 176 struct list_head node_ref_from; /* list node */ 177 struct list_head collision_resolving_node; /* list node */ 178 struct btrfsic_block *block_ref_to; 179 struct btrfsic_block *block_ref_from; 180 u64 parent_generation; 181 }; 182 183 struct btrfsic_dev_state { 184 u32 magic_num; /* only used for debug purposes */ 185 struct block_device *bdev; 186 struct btrfsic_state *state; 187 struct list_head collision_resolving_node; /* list node */ 188 struct btrfsic_block dummy_block_for_bio_bh_flush; 189 u64 last_flush_gen; 190 }; 191 192 struct btrfsic_block_hashtable { 193 struct list_head table[BTRFSIC_BLOCK_HASHTABLE_SIZE]; 194 }; 195 196 struct btrfsic_block_link_hashtable { 197 struct list_head table[BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE]; 198 }; 199 200 struct btrfsic_dev_state_hashtable { 201 struct list_head table[BTRFSIC_DEV2STATE_HASHTABLE_SIZE]; 202 }; 203 204 struct btrfsic_block_data_ctx { 205 u64 start; /* virtual bytenr */ 206 u64 dev_bytenr; /* physical bytenr on device */ 207 u32 len; 208 struct btrfsic_dev_state *dev; 209 char **datav; 210 struct page **pagev; 211 void *mem_to_free; 212 }; 213 214 /* This structure is used to implement recursion without occupying 215 * any stack space, refer to btrfsic_process_metablock() */ 216 struct btrfsic_stack_frame { 217 u32 magic; 218 u32 nr; 219 int error; 220 int i; 221 int limit_nesting; 222 int num_copies; 223 int mirror_num; 224 struct btrfsic_block *block; 225 struct btrfsic_block_data_ctx *block_ctx; 226 struct btrfsic_block *next_block; 227 struct btrfsic_block_data_ctx next_block_ctx; 228 struct btrfs_header *hdr; 229 struct btrfsic_stack_frame *prev; 230 }; 231 232 /* Some state per mounted filesystem */ 233 struct btrfsic_state { 234 u32 print_mask; 235 int include_extent_data; 236 struct list_head all_blocks_list; 237 struct btrfsic_block_hashtable block_hashtable; 238 struct btrfsic_block_link_hashtable block_link_hashtable; 239 struct btrfs_fs_info *fs_info; 240 u64 max_superblock_generation; 241 struct btrfsic_block *latest_superblock; 242 u32 metablock_size; 243 u32 datablock_size; 244 }; 245 246 static int btrfsic_process_metablock(struct btrfsic_state *state, 247 struct btrfsic_block *block, 248 struct btrfsic_block_data_ctx *block_ctx, 249 int limit_nesting, int force_iodone_flag); 250 static void btrfsic_read_from_block_data( 251 struct btrfsic_block_data_ctx *block_ctx, 252 void *dst, u32 offset, size_t len); 253 static int btrfsic_create_link_to_next_block( 254 struct btrfsic_state *state, 255 struct btrfsic_block *block, 256 struct btrfsic_block_data_ctx 257 *block_ctx, u64 next_bytenr, 258 int limit_nesting, 259 struct btrfsic_block_data_ctx *next_block_ctx, 260 struct btrfsic_block **next_blockp, 261 int force_iodone_flag, 262 int *num_copiesp, int *mirror_nump, 263 struct btrfs_disk_key *disk_key, 264 u64 parent_generation); 265 static int btrfsic_handle_extent_data(struct btrfsic_state *state, 266 struct btrfsic_block *block, 267 struct btrfsic_block_data_ctx *block_ctx, 268 u32 item_offset, int force_iodone_flag); 269 static int btrfsic_map_block(struct btrfsic_state *state, u64 bytenr, u32 len, 270 struct btrfsic_block_data_ctx *block_ctx_out, 271 int mirror_num); 272 static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx); 273 static int btrfsic_read_block(struct btrfsic_state *state, 274 struct btrfsic_block_data_ctx *block_ctx); 275 static int btrfsic_process_written_superblock( 276 struct btrfsic_state *state, 277 struct btrfsic_block *const block, 278 struct btrfs_super_block *const super_hdr); 279 static void btrfsic_bio_end_io(struct bio *bp); 280 static int btrfsic_is_block_ref_by_superblock(const struct btrfsic_state *state, 281 const struct btrfsic_block *block, 282 int recursion_level); 283 static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state, 284 struct btrfsic_block *const block, 285 int recursion_level); 286 static void btrfsic_print_add_link(const struct btrfsic_state *state, 287 const struct btrfsic_block_link *l); 288 static void btrfsic_print_rem_link(const struct btrfsic_state *state, 289 const struct btrfsic_block_link *l); 290 static char btrfsic_get_block_type(const struct btrfsic_state *state, 291 const struct btrfsic_block *block); 292 static void btrfsic_dump_tree(const struct btrfsic_state *state); 293 static void btrfsic_dump_tree_sub(const struct btrfsic_state *state, 294 const struct btrfsic_block *block, 295 int indent_level); 296 static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add( 297 struct btrfsic_state *state, 298 struct btrfsic_block_data_ctx *next_block_ctx, 299 struct btrfsic_block *next_block, 300 struct btrfsic_block *from_block, 301 u64 parent_generation); 302 static struct btrfsic_block *btrfsic_block_lookup_or_add( 303 struct btrfsic_state *state, 304 struct btrfsic_block_data_ctx *block_ctx, 305 const char *additional_string, 306 int is_metadata, 307 int is_iodone, 308 int never_written, 309 int mirror_num, 310 int *was_created); 311 static int btrfsic_process_superblock_dev_mirror( 312 struct btrfsic_state *state, 313 struct btrfsic_dev_state *dev_state, 314 struct btrfs_device *device, 315 int superblock_mirror_num, 316 struct btrfsic_dev_state **selected_dev_state, 317 struct btrfs_super_block *selected_super); 318 static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev); 319 static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state, 320 u64 bytenr, 321 struct btrfsic_dev_state *dev_state, 322 u64 dev_bytenr); 323 324 static struct mutex btrfsic_mutex; 325 static int btrfsic_is_initialized; 326 static struct btrfsic_dev_state_hashtable btrfsic_dev_state_hashtable; 327 328 329 static void btrfsic_block_init(struct btrfsic_block *b) 330 { 331 b->magic_num = BTRFSIC_BLOCK_MAGIC_NUMBER; 332 b->dev_state = NULL; 333 b->dev_bytenr = 0; 334 b->logical_bytenr = 0; 335 b->generation = BTRFSIC_GENERATION_UNKNOWN; 336 b->disk_key.objectid = 0; 337 b->disk_key.type = 0; 338 b->disk_key.offset = 0; 339 b->is_metadata = 0; 340 b->is_superblock = 0; 341 b->is_iodone = 0; 342 b->iodone_w_error = 0; 343 b->never_written = 0; 344 b->mirror_num = 0; 345 b->next_in_same_bio = NULL; 346 b->orig_bio_private = NULL; 347 b->orig_bio_end_io = NULL; 348 INIT_LIST_HEAD(&b->collision_resolving_node); 349 INIT_LIST_HEAD(&b->all_blocks_node); 350 INIT_LIST_HEAD(&b->ref_to_list); 351 INIT_LIST_HEAD(&b->ref_from_list); 352 b->submit_bio_bh_rw = 0; 353 b->flush_gen = 0; 354 } 355 356 static struct btrfsic_block *btrfsic_block_alloc(void) 357 { 358 struct btrfsic_block *b; 359 360 b = kzalloc(sizeof(*b), GFP_NOFS); 361 if (NULL != b) 362 btrfsic_block_init(b); 363 364 return b; 365 } 366 367 static void btrfsic_block_free(struct btrfsic_block *b) 368 { 369 BUG_ON(!(NULL == b || BTRFSIC_BLOCK_MAGIC_NUMBER == b->magic_num)); 370 kfree(b); 371 } 372 373 static void btrfsic_block_link_init(struct btrfsic_block_link *l) 374 { 375 l->magic_num = BTRFSIC_BLOCK_LINK_MAGIC_NUMBER; 376 l->ref_cnt = 1; 377 INIT_LIST_HEAD(&l->node_ref_to); 378 INIT_LIST_HEAD(&l->node_ref_from); 379 INIT_LIST_HEAD(&l->collision_resolving_node); 380 l->block_ref_to = NULL; 381 l->block_ref_from = NULL; 382 } 383 384 static struct btrfsic_block_link *btrfsic_block_link_alloc(void) 385 { 386 struct btrfsic_block_link *l; 387 388 l = kzalloc(sizeof(*l), GFP_NOFS); 389 if (NULL != l) 390 btrfsic_block_link_init(l); 391 392 return l; 393 } 394 395 static void btrfsic_block_link_free(struct btrfsic_block_link *l) 396 { 397 BUG_ON(!(NULL == l || BTRFSIC_BLOCK_LINK_MAGIC_NUMBER == l->magic_num)); 398 kfree(l); 399 } 400 401 static void btrfsic_dev_state_init(struct btrfsic_dev_state *ds) 402 { 403 ds->magic_num = BTRFSIC_DEV2STATE_MAGIC_NUMBER; 404 ds->bdev = NULL; 405 ds->state = NULL; 406 INIT_LIST_HEAD(&ds->collision_resolving_node); 407 ds->last_flush_gen = 0; 408 btrfsic_block_init(&ds->dummy_block_for_bio_bh_flush); 409 ds->dummy_block_for_bio_bh_flush.is_iodone = 1; 410 ds->dummy_block_for_bio_bh_flush.dev_state = ds; 411 } 412 413 static struct btrfsic_dev_state *btrfsic_dev_state_alloc(void) 414 { 415 struct btrfsic_dev_state *ds; 416 417 ds = kzalloc(sizeof(*ds), GFP_NOFS); 418 if (NULL != ds) 419 btrfsic_dev_state_init(ds); 420 421 return ds; 422 } 423 424 static void btrfsic_dev_state_free(struct btrfsic_dev_state *ds) 425 { 426 BUG_ON(!(NULL == ds || 427 BTRFSIC_DEV2STATE_MAGIC_NUMBER == ds->magic_num)); 428 kfree(ds); 429 } 430 431 static void btrfsic_block_hashtable_init(struct btrfsic_block_hashtable *h) 432 { 433 int i; 434 435 for (i = 0; i < BTRFSIC_BLOCK_HASHTABLE_SIZE; i++) 436 INIT_LIST_HEAD(h->table + i); 437 } 438 439 static void btrfsic_block_hashtable_add(struct btrfsic_block *b, 440 struct btrfsic_block_hashtable *h) 441 { 442 const unsigned int hashval = 443 (((unsigned int)(b->dev_bytenr >> 16)) ^ 444 ((unsigned int)((uintptr_t)b->dev_state->bdev))) & 445 (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1); 446 447 list_add(&b->collision_resolving_node, h->table + hashval); 448 } 449 450 static void btrfsic_block_hashtable_remove(struct btrfsic_block *b) 451 { 452 list_del(&b->collision_resolving_node); 453 } 454 455 static struct btrfsic_block *btrfsic_block_hashtable_lookup( 456 struct block_device *bdev, 457 u64 dev_bytenr, 458 struct btrfsic_block_hashtable *h) 459 { 460 const unsigned int hashval = 461 (((unsigned int)(dev_bytenr >> 16)) ^ 462 ((unsigned int)((uintptr_t)bdev))) & 463 (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1); 464 struct btrfsic_block *b; 465 466 list_for_each_entry(b, h->table + hashval, collision_resolving_node) { 467 if (b->dev_state->bdev == bdev && b->dev_bytenr == dev_bytenr) 468 return b; 469 } 470 471 return NULL; 472 } 473 474 static void btrfsic_block_link_hashtable_init( 475 struct btrfsic_block_link_hashtable *h) 476 { 477 int i; 478 479 for (i = 0; i < BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE; i++) 480 INIT_LIST_HEAD(h->table + i); 481 } 482 483 static void btrfsic_block_link_hashtable_add( 484 struct btrfsic_block_link *l, 485 struct btrfsic_block_link_hashtable *h) 486 { 487 const unsigned int hashval = 488 (((unsigned int)(l->block_ref_to->dev_bytenr >> 16)) ^ 489 ((unsigned int)(l->block_ref_from->dev_bytenr >> 16)) ^ 490 ((unsigned int)((uintptr_t)l->block_ref_to->dev_state->bdev)) ^ 491 ((unsigned int)((uintptr_t)l->block_ref_from->dev_state->bdev))) 492 & (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1); 493 494 BUG_ON(NULL == l->block_ref_to); 495 BUG_ON(NULL == l->block_ref_from); 496 list_add(&l->collision_resolving_node, h->table + hashval); 497 } 498 499 static void btrfsic_block_link_hashtable_remove(struct btrfsic_block_link *l) 500 { 501 list_del(&l->collision_resolving_node); 502 } 503 504 static struct btrfsic_block_link *btrfsic_block_link_hashtable_lookup( 505 struct block_device *bdev_ref_to, 506 u64 dev_bytenr_ref_to, 507 struct block_device *bdev_ref_from, 508 u64 dev_bytenr_ref_from, 509 struct btrfsic_block_link_hashtable *h) 510 { 511 const unsigned int hashval = 512 (((unsigned int)(dev_bytenr_ref_to >> 16)) ^ 513 ((unsigned int)(dev_bytenr_ref_from >> 16)) ^ 514 ((unsigned int)((uintptr_t)bdev_ref_to)) ^ 515 ((unsigned int)((uintptr_t)bdev_ref_from))) & 516 (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1); 517 struct btrfsic_block_link *l; 518 519 list_for_each_entry(l, h->table + hashval, collision_resolving_node) { 520 BUG_ON(NULL == l->block_ref_to); 521 BUG_ON(NULL == l->block_ref_from); 522 if (l->block_ref_to->dev_state->bdev == bdev_ref_to && 523 l->block_ref_to->dev_bytenr == dev_bytenr_ref_to && 524 l->block_ref_from->dev_state->bdev == bdev_ref_from && 525 l->block_ref_from->dev_bytenr == dev_bytenr_ref_from) 526 return l; 527 } 528 529 return NULL; 530 } 531 532 static void btrfsic_dev_state_hashtable_init( 533 struct btrfsic_dev_state_hashtable *h) 534 { 535 int i; 536 537 for (i = 0; i < BTRFSIC_DEV2STATE_HASHTABLE_SIZE; i++) 538 INIT_LIST_HEAD(h->table + i); 539 } 540 541 static void btrfsic_dev_state_hashtable_add( 542 struct btrfsic_dev_state *ds, 543 struct btrfsic_dev_state_hashtable *h) 544 { 545 const unsigned int hashval = 546 (((unsigned int)((uintptr_t)ds->bdev->bd_dev)) & 547 (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1)); 548 549 list_add(&ds->collision_resolving_node, h->table + hashval); 550 } 551 552 static void btrfsic_dev_state_hashtable_remove(struct btrfsic_dev_state *ds) 553 { 554 list_del(&ds->collision_resolving_node); 555 } 556 557 static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(dev_t dev, 558 struct btrfsic_dev_state_hashtable *h) 559 { 560 const unsigned int hashval = 561 dev & (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1); 562 struct btrfsic_dev_state *ds; 563 564 list_for_each_entry(ds, h->table + hashval, collision_resolving_node) { 565 if (ds->bdev->bd_dev == dev) 566 return ds; 567 } 568 569 return NULL; 570 } 571 572 static int btrfsic_process_superblock(struct btrfsic_state *state, 573 struct btrfs_fs_devices *fs_devices) 574 { 575 struct btrfs_super_block *selected_super; 576 struct list_head *dev_head = &fs_devices->devices; 577 struct btrfs_device *device; 578 struct btrfsic_dev_state *selected_dev_state = NULL; 579 int ret = 0; 580 int pass; 581 582 selected_super = kzalloc(sizeof(*selected_super), GFP_NOFS); 583 if (!selected_super) 584 return -ENOMEM; 585 586 list_for_each_entry(device, dev_head, dev_list) { 587 int i; 588 struct btrfsic_dev_state *dev_state; 589 590 if (!device->bdev || !device->name) 591 continue; 592 593 dev_state = btrfsic_dev_state_lookup(device->bdev->bd_dev); 594 BUG_ON(NULL == dev_state); 595 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) { 596 ret = btrfsic_process_superblock_dev_mirror( 597 state, dev_state, device, i, 598 &selected_dev_state, selected_super); 599 if (0 != ret && 0 == i) { 600 kfree(selected_super); 601 return ret; 602 } 603 } 604 } 605 606 if (NULL == state->latest_superblock) { 607 pr_info("btrfsic: no superblock found!\n"); 608 kfree(selected_super); 609 return -1; 610 } 611 612 for (pass = 0; pass < 3; pass++) { 613 int num_copies; 614 int mirror_num; 615 u64 next_bytenr; 616 617 switch (pass) { 618 case 0: 619 next_bytenr = btrfs_super_root(selected_super); 620 if (state->print_mask & 621 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 622 pr_info("root@%llu\n", next_bytenr); 623 break; 624 case 1: 625 next_bytenr = btrfs_super_chunk_root(selected_super); 626 if (state->print_mask & 627 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 628 pr_info("chunk@%llu\n", next_bytenr); 629 break; 630 case 2: 631 next_bytenr = btrfs_super_log_root(selected_super); 632 if (0 == next_bytenr) 633 continue; 634 if (state->print_mask & 635 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 636 pr_info("log@%llu\n", next_bytenr); 637 break; 638 } 639 640 num_copies = btrfs_num_copies(state->fs_info, next_bytenr, 641 state->metablock_size); 642 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 643 pr_info("num_copies(log_bytenr=%llu) = %d\n", 644 next_bytenr, num_copies); 645 646 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 647 struct btrfsic_block *next_block; 648 struct btrfsic_block_data_ctx tmp_next_block_ctx; 649 struct btrfsic_block_link *l; 650 651 ret = btrfsic_map_block(state, next_bytenr, 652 state->metablock_size, 653 &tmp_next_block_ctx, 654 mirror_num); 655 if (ret) { 656 pr_info("btrfsic: btrfsic_map_block(root @%llu, mirror %d) failed!\n", 657 next_bytenr, mirror_num); 658 kfree(selected_super); 659 return -1; 660 } 661 662 next_block = btrfsic_block_hashtable_lookup( 663 tmp_next_block_ctx.dev->bdev, 664 tmp_next_block_ctx.dev_bytenr, 665 &state->block_hashtable); 666 BUG_ON(NULL == next_block); 667 668 l = btrfsic_block_link_hashtable_lookup( 669 tmp_next_block_ctx.dev->bdev, 670 tmp_next_block_ctx.dev_bytenr, 671 state->latest_superblock->dev_state-> 672 bdev, 673 state->latest_superblock->dev_bytenr, 674 &state->block_link_hashtable); 675 BUG_ON(NULL == l); 676 677 ret = btrfsic_read_block(state, &tmp_next_block_ctx); 678 if (ret < (int)PAGE_SIZE) { 679 pr_info("btrfsic: read @logical %llu failed!\n", 680 tmp_next_block_ctx.start); 681 btrfsic_release_block_ctx(&tmp_next_block_ctx); 682 kfree(selected_super); 683 return -1; 684 } 685 686 ret = btrfsic_process_metablock(state, 687 next_block, 688 &tmp_next_block_ctx, 689 BTRFS_MAX_LEVEL + 3, 1); 690 btrfsic_release_block_ctx(&tmp_next_block_ctx); 691 } 692 } 693 694 kfree(selected_super); 695 return ret; 696 } 697 698 static int btrfsic_process_superblock_dev_mirror( 699 struct btrfsic_state *state, 700 struct btrfsic_dev_state *dev_state, 701 struct btrfs_device *device, 702 int superblock_mirror_num, 703 struct btrfsic_dev_state **selected_dev_state, 704 struct btrfs_super_block *selected_super) 705 { 706 struct btrfs_fs_info *fs_info = state->fs_info; 707 struct btrfs_super_block *super_tmp; 708 u64 dev_bytenr; 709 struct btrfsic_block *superblock_tmp; 710 int pass; 711 struct block_device *const superblock_bdev = device->bdev; 712 struct page *page; 713 struct address_space *mapping = superblock_bdev->bd_inode->i_mapping; 714 int ret = 0; 715 716 /* super block bytenr is always the unmapped device bytenr */ 717 dev_bytenr = btrfs_sb_offset(superblock_mirror_num); 718 if (dev_bytenr + BTRFS_SUPER_INFO_SIZE > device->commit_total_bytes) 719 return -1; 720 721 page = read_cache_page_gfp(mapping, dev_bytenr >> PAGE_SHIFT, GFP_NOFS); 722 if (IS_ERR(page)) 723 return -1; 724 725 super_tmp = page_address(page); 726 727 if (btrfs_super_bytenr(super_tmp) != dev_bytenr || 728 btrfs_super_magic(super_tmp) != BTRFS_MAGIC || 729 memcmp(device->uuid, super_tmp->dev_item.uuid, BTRFS_UUID_SIZE) || 730 btrfs_super_nodesize(super_tmp) != state->metablock_size || 731 btrfs_super_sectorsize(super_tmp) != state->datablock_size) { 732 ret = 0; 733 goto out; 734 } 735 736 superblock_tmp = 737 btrfsic_block_hashtable_lookup(superblock_bdev, 738 dev_bytenr, 739 &state->block_hashtable); 740 if (NULL == superblock_tmp) { 741 superblock_tmp = btrfsic_block_alloc(); 742 if (NULL == superblock_tmp) { 743 ret = -1; 744 goto out; 745 } 746 /* for superblock, only the dev_bytenr makes sense */ 747 superblock_tmp->dev_bytenr = dev_bytenr; 748 superblock_tmp->dev_state = dev_state; 749 superblock_tmp->logical_bytenr = dev_bytenr; 750 superblock_tmp->generation = btrfs_super_generation(super_tmp); 751 superblock_tmp->is_metadata = 1; 752 superblock_tmp->is_superblock = 1; 753 superblock_tmp->is_iodone = 1; 754 superblock_tmp->never_written = 0; 755 superblock_tmp->mirror_num = 1 + superblock_mirror_num; 756 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE) 757 btrfs_info_in_rcu(fs_info, 758 "new initial S-block (bdev %p, %s) @%llu (%pg/%llu/%d)", 759 superblock_bdev, 760 btrfs_dev_name(device), dev_bytenr, 761 dev_state->bdev, dev_bytenr, 762 superblock_mirror_num); 763 list_add(&superblock_tmp->all_blocks_node, 764 &state->all_blocks_list); 765 btrfsic_block_hashtable_add(superblock_tmp, 766 &state->block_hashtable); 767 } 768 769 /* select the one with the highest generation field */ 770 if (btrfs_super_generation(super_tmp) > 771 state->max_superblock_generation || 772 0 == state->max_superblock_generation) { 773 memcpy(selected_super, super_tmp, sizeof(*selected_super)); 774 *selected_dev_state = dev_state; 775 state->max_superblock_generation = 776 btrfs_super_generation(super_tmp); 777 state->latest_superblock = superblock_tmp; 778 } 779 780 for (pass = 0; pass < 3; pass++) { 781 u64 next_bytenr; 782 int num_copies; 783 int mirror_num; 784 const char *additional_string = NULL; 785 struct btrfs_disk_key tmp_disk_key; 786 787 tmp_disk_key.type = BTRFS_ROOT_ITEM_KEY; 788 tmp_disk_key.offset = 0; 789 switch (pass) { 790 case 0: 791 btrfs_set_disk_key_objectid(&tmp_disk_key, 792 BTRFS_ROOT_TREE_OBJECTID); 793 additional_string = "initial root "; 794 next_bytenr = btrfs_super_root(super_tmp); 795 break; 796 case 1: 797 btrfs_set_disk_key_objectid(&tmp_disk_key, 798 BTRFS_CHUNK_TREE_OBJECTID); 799 additional_string = "initial chunk "; 800 next_bytenr = btrfs_super_chunk_root(super_tmp); 801 break; 802 case 2: 803 btrfs_set_disk_key_objectid(&tmp_disk_key, 804 BTRFS_TREE_LOG_OBJECTID); 805 additional_string = "initial log "; 806 next_bytenr = btrfs_super_log_root(super_tmp); 807 if (0 == next_bytenr) 808 continue; 809 break; 810 } 811 812 num_copies = btrfs_num_copies(fs_info, next_bytenr, 813 state->metablock_size); 814 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 815 pr_info("num_copies(log_bytenr=%llu) = %d\n", 816 next_bytenr, num_copies); 817 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 818 struct btrfsic_block *next_block; 819 struct btrfsic_block_data_ctx tmp_next_block_ctx; 820 struct btrfsic_block_link *l; 821 822 if (btrfsic_map_block(state, next_bytenr, 823 state->metablock_size, 824 &tmp_next_block_ctx, 825 mirror_num)) { 826 pr_info("btrfsic: btrfsic_map_block(bytenr @%llu, mirror %d) failed!\n", 827 next_bytenr, mirror_num); 828 ret = -1; 829 goto out; 830 } 831 832 next_block = btrfsic_block_lookup_or_add( 833 state, &tmp_next_block_ctx, 834 additional_string, 1, 1, 0, 835 mirror_num, NULL); 836 if (NULL == next_block) { 837 btrfsic_release_block_ctx(&tmp_next_block_ctx); 838 ret = -1; 839 goto out; 840 } 841 842 next_block->disk_key = tmp_disk_key; 843 next_block->generation = BTRFSIC_GENERATION_UNKNOWN; 844 l = btrfsic_block_link_lookup_or_add( 845 state, &tmp_next_block_ctx, 846 next_block, superblock_tmp, 847 BTRFSIC_GENERATION_UNKNOWN); 848 btrfsic_release_block_ctx(&tmp_next_block_ctx); 849 if (NULL == l) { 850 ret = -1; 851 goto out; 852 } 853 } 854 } 855 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_ALL_TREES) 856 btrfsic_dump_tree_sub(state, superblock_tmp, 0); 857 858 out: 859 put_page(page); 860 return ret; 861 } 862 863 static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void) 864 { 865 struct btrfsic_stack_frame *sf; 866 867 sf = kzalloc(sizeof(*sf), GFP_NOFS); 868 if (sf) 869 sf->magic = BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER; 870 return sf; 871 } 872 873 static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf) 874 { 875 BUG_ON(!(NULL == sf || 876 BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER == sf->magic)); 877 kfree(sf); 878 } 879 880 static noinline_for_stack int btrfsic_process_metablock( 881 struct btrfsic_state *state, 882 struct btrfsic_block *const first_block, 883 struct btrfsic_block_data_ctx *const first_block_ctx, 884 int first_limit_nesting, int force_iodone_flag) 885 { 886 struct btrfsic_stack_frame initial_stack_frame = { 0 }; 887 struct btrfsic_stack_frame *sf; 888 struct btrfsic_stack_frame *next_stack; 889 struct btrfs_header *const first_hdr = 890 (struct btrfs_header *)first_block_ctx->datav[0]; 891 892 BUG_ON(!first_hdr); 893 sf = &initial_stack_frame; 894 sf->error = 0; 895 sf->i = -1; 896 sf->limit_nesting = first_limit_nesting; 897 sf->block = first_block; 898 sf->block_ctx = first_block_ctx; 899 sf->next_block = NULL; 900 sf->hdr = first_hdr; 901 sf->prev = NULL; 902 903 continue_with_new_stack_frame: 904 sf->block->generation = btrfs_stack_header_generation(sf->hdr); 905 if (0 == sf->hdr->level) { 906 struct btrfs_leaf *const leafhdr = 907 (struct btrfs_leaf *)sf->hdr; 908 909 if (-1 == sf->i) { 910 sf->nr = btrfs_stack_header_nritems(&leafhdr->header); 911 912 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 913 pr_info("leaf %llu items %d generation %llu owner %llu\n", 914 sf->block_ctx->start, sf->nr, 915 btrfs_stack_header_generation( 916 &leafhdr->header), 917 btrfs_stack_header_owner( 918 &leafhdr->header)); 919 } 920 921 continue_with_current_leaf_stack_frame: 922 if (0 == sf->num_copies || sf->mirror_num > sf->num_copies) { 923 sf->i++; 924 sf->num_copies = 0; 925 } 926 927 if (sf->i < sf->nr) { 928 struct btrfs_item disk_item; 929 u32 disk_item_offset = 930 (uintptr_t)(leafhdr->items + sf->i) - 931 (uintptr_t)leafhdr; 932 struct btrfs_disk_key *disk_key; 933 u8 type; 934 u32 item_offset; 935 u32 item_size; 936 937 if (disk_item_offset + sizeof(struct btrfs_item) > 938 sf->block_ctx->len) { 939 leaf_item_out_of_bounce_error: 940 pr_info( 941 "btrfsic: leaf item out of bounce at logical %llu, dev %pg\n", 942 sf->block_ctx->start, 943 sf->block_ctx->dev->bdev); 944 goto one_stack_frame_backwards; 945 } 946 btrfsic_read_from_block_data(sf->block_ctx, 947 &disk_item, 948 disk_item_offset, 949 sizeof(struct btrfs_item)); 950 item_offset = btrfs_stack_item_offset(&disk_item); 951 item_size = btrfs_stack_item_size(&disk_item); 952 disk_key = &disk_item.key; 953 type = btrfs_disk_key_type(disk_key); 954 955 if (BTRFS_ROOT_ITEM_KEY == type) { 956 struct btrfs_root_item root_item; 957 u32 root_item_offset; 958 u64 next_bytenr; 959 960 root_item_offset = item_offset + 961 offsetof(struct btrfs_leaf, items); 962 if (root_item_offset + item_size > 963 sf->block_ctx->len) 964 goto leaf_item_out_of_bounce_error; 965 btrfsic_read_from_block_data( 966 sf->block_ctx, &root_item, 967 root_item_offset, 968 item_size); 969 next_bytenr = btrfs_root_bytenr(&root_item); 970 971 sf->error = 972 btrfsic_create_link_to_next_block( 973 state, 974 sf->block, 975 sf->block_ctx, 976 next_bytenr, 977 sf->limit_nesting, 978 &sf->next_block_ctx, 979 &sf->next_block, 980 force_iodone_flag, 981 &sf->num_copies, 982 &sf->mirror_num, 983 disk_key, 984 btrfs_root_generation( 985 &root_item)); 986 if (sf->error) 987 goto one_stack_frame_backwards; 988 989 if (NULL != sf->next_block) { 990 struct btrfs_header *const next_hdr = 991 (struct btrfs_header *) 992 sf->next_block_ctx.datav[0]; 993 994 next_stack = 995 btrfsic_stack_frame_alloc(); 996 if (NULL == next_stack) { 997 sf->error = -1; 998 btrfsic_release_block_ctx( 999 &sf-> 1000 next_block_ctx); 1001 goto one_stack_frame_backwards; 1002 } 1003 1004 next_stack->i = -1; 1005 next_stack->block = sf->next_block; 1006 next_stack->block_ctx = 1007 &sf->next_block_ctx; 1008 next_stack->next_block = NULL; 1009 next_stack->hdr = next_hdr; 1010 next_stack->limit_nesting = 1011 sf->limit_nesting - 1; 1012 next_stack->prev = sf; 1013 sf = next_stack; 1014 goto continue_with_new_stack_frame; 1015 } 1016 } else if (BTRFS_EXTENT_DATA_KEY == type && 1017 state->include_extent_data) { 1018 sf->error = btrfsic_handle_extent_data( 1019 state, 1020 sf->block, 1021 sf->block_ctx, 1022 item_offset, 1023 force_iodone_flag); 1024 if (sf->error) 1025 goto one_stack_frame_backwards; 1026 } 1027 1028 goto continue_with_current_leaf_stack_frame; 1029 } 1030 } else { 1031 struct btrfs_node *const nodehdr = (struct btrfs_node *)sf->hdr; 1032 1033 if (-1 == sf->i) { 1034 sf->nr = btrfs_stack_header_nritems(&nodehdr->header); 1035 1036 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1037 pr_info("node %llu level %d items %d generation %llu owner %llu\n", 1038 sf->block_ctx->start, 1039 nodehdr->header.level, sf->nr, 1040 btrfs_stack_header_generation( 1041 &nodehdr->header), 1042 btrfs_stack_header_owner( 1043 &nodehdr->header)); 1044 } 1045 1046 continue_with_current_node_stack_frame: 1047 if (0 == sf->num_copies || sf->mirror_num > sf->num_copies) { 1048 sf->i++; 1049 sf->num_copies = 0; 1050 } 1051 1052 if (sf->i < sf->nr) { 1053 struct btrfs_key_ptr key_ptr; 1054 u32 key_ptr_offset; 1055 u64 next_bytenr; 1056 1057 key_ptr_offset = (uintptr_t)(nodehdr->ptrs + sf->i) - 1058 (uintptr_t)nodehdr; 1059 if (key_ptr_offset + sizeof(struct btrfs_key_ptr) > 1060 sf->block_ctx->len) { 1061 pr_info( 1062 "btrfsic: node item out of bounce at logical %llu, dev %pg\n", 1063 sf->block_ctx->start, 1064 sf->block_ctx->dev->bdev); 1065 goto one_stack_frame_backwards; 1066 } 1067 btrfsic_read_from_block_data( 1068 sf->block_ctx, &key_ptr, key_ptr_offset, 1069 sizeof(struct btrfs_key_ptr)); 1070 next_bytenr = btrfs_stack_key_blockptr(&key_ptr); 1071 1072 sf->error = btrfsic_create_link_to_next_block( 1073 state, 1074 sf->block, 1075 sf->block_ctx, 1076 next_bytenr, 1077 sf->limit_nesting, 1078 &sf->next_block_ctx, 1079 &sf->next_block, 1080 force_iodone_flag, 1081 &sf->num_copies, 1082 &sf->mirror_num, 1083 &key_ptr.key, 1084 btrfs_stack_key_generation(&key_ptr)); 1085 if (sf->error) 1086 goto one_stack_frame_backwards; 1087 1088 if (NULL != sf->next_block) { 1089 struct btrfs_header *const next_hdr = 1090 (struct btrfs_header *) 1091 sf->next_block_ctx.datav[0]; 1092 1093 next_stack = btrfsic_stack_frame_alloc(); 1094 if (NULL == next_stack) { 1095 sf->error = -1; 1096 goto one_stack_frame_backwards; 1097 } 1098 1099 next_stack->i = -1; 1100 next_stack->block = sf->next_block; 1101 next_stack->block_ctx = &sf->next_block_ctx; 1102 next_stack->next_block = NULL; 1103 next_stack->hdr = next_hdr; 1104 next_stack->limit_nesting = 1105 sf->limit_nesting - 1; 1106 next_stack->prev = sf; 1107 sf = next_stack; 1108 goto continue_with_new_stack_frame; 1109 } 1110 1111 goto continue_with_current_node_stack_frame; 1112 } 1113 } 1114 1115 one_stack_frame_backwards: 1116 if (NULL != sf->prev) { 1117 struct btrfsic_stack_frame *const prev = sf->prev; 1118 1119 /* the one for the initial block is freed in the caller */ 1120 btrfsic_release_block_ctx(sf->block_ctx); 1121 1122 if (sf->error) { 1123 prev->error = sf->error; 1124 btrfsic_stack_frame_free(sf); 1125 sf = prev; 1126 goto one_stack_frame_backwards; 1127 } 1128 1129 btrfsic_stack_frame_free(sf); 1130 sf = prev; 1131 goto continue_with_new_stack_frame; 1132 } else { 1133 BUG_ON(&initial_stack_frame != sf); 1134 } 1135 1136 return sf->error; 1137 } 1138 1139 static void btrfsic_read_from_block_data( 1140 struct btrfsic_block_data_ctx *block_ctx, 1141 void *dstv, u32 offset, size_t len) 1142 { 1143 size_t cur; 1144 size_t pgoff; 1145 char *kaddr; 1146 char *dst = (char *)dstv; 1147 size_t start_offset = offset_in_page(block_ctx->start); 1148 unsigned long i = (start_offset + offset) >> PAGE_SHIFT; 1149 1150 WARN_ON(offset + len > block_ctx->len); 1151 pgoff = offset_in_page(start_offset + offset); 1152 1153 while (len > 0) { 1154 cur = min(len, ((size_t)PAGE_SIZE - pgoff)); 1155 BUG_ON(i >= DIV_ROUND_UP(block_ctx->len, PAGE_SIZE)); 1156 kaddr = block_ctx->datav[i]; 1157 memcpy(dst, kaddr + pgoff, cur); 1158 1159 dst += cur; 1160 len -= cur; 1161 pgoff = 0; 1162 i++; 1163 } 1164 } 1165 1166 static int btrfsic_create_link_to_next_block( 1167 struct btrfsic_state *state, 1168 struct btrfsic_block *block, 1169 struct btrfsic_block_data_ctx *block_ctx, 1170 u64 next_bytenr, 1171 int limit_nesting, 1172 struct btrfsic_block_data_ctx *next_block_ctx, 1173 struct btrfsic_block **next_blockp, 1174 int force_iodone_flag, 1175 int *num_copiesp, int *mirror_nump, 1176 struct btrfs_disk_key *disk_key, 1177 u64 parent_generation) 1178 { 1179 struct btrfs_fs_info *fs_info = state->fs_info; 1180 struct btrfsic_block *next_block = NULL; 1181 int ret; 1182 struct btrfsic_block_link *l; 1183 int did_alloc_block_link; 1184 int block_was_created; 1185 1186 *next_blockp = NULL; 1187 if (0 == *num_copiesp) { 1188 *num_copiesp = btrfs_num_copies(fs_info, next_bytenr, 1189 state->metablock_size); 1190 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 1191 pr_info("num_copies(log_bytenr=%llu) = %d\n", 1192 next_bytenr, *num_copiesp); 1193 *mirror_nump = 1; 1194 } 1195 1196 if (*mirror_nump > *num_copiesp) 1197 return 0; 1198 1199 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1200 pr_info("btrfsic_create_link_to_next_block(mirror_num=%d)\n", 1201 *mirror_nump); 1202 ret = btrfsic_map_block(state, next_bytenr, 1203 state->metablock_size, 1204 next_block_ctx, *mirror_nump); 1205 if (ret) { 1206 pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n", 1207 next_bytenr, *mirror_nump); 1208 btrfsic_release_block_ctx(next_block_ctx); 1209 *next_blockp = NULL; 1210 return -1; 1211 } 1212 1213 next_block = btrfsic_block_lookup_or_add(state, 1214 next_block_ctx, "referenced ", 1215 1, force_iodone_flag, 1216 !force_iodone_flag, 1217 *mirror_nump, 1218 &block_was_created); 1219 if (NULL == next_block) { 1220 btrfsic_release_block_ctx(next_block_ctx); 1221 *next_blockp = NULL; 1222 return -1; 1223 } 1224 if (block_was_created) { 1225 l = NULL; 1226 next_block->generation = BTRFSIC_GENERATION_UNKNOWN; 1227 } else { 1228 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) { 1229 if (next_block->logical_bytenr != next_bytenr && 1230 !(!next_block->is_metadata && 1231 0 == next_block->logical_bytenr)) 1232 pr_info( 1233 "referenced block @%llu (%pg/%llu/%d) found in hash table, %c, bytenr mismatch (!= stored %llu)\n", 1234 next_bytenr, next_block_ctx->dev->bdev, 1235 next_block_ctx->dev_bytenr, *mirror_nump, 1236 btrfsic_get_block_type(state, 1237 next_block), 1238 next_block->logical_bytenr); 1239 else 1240 pr_info( 1241 "referenced block @%llu (%pg/%llu/%d) found in hash table, %c\n", 1242 next_bytenr, next_block_ctx->dev->bdev, 1243 next_block_ctx->dev_bytenr, *mirror_nump, 1244 btrfsic_get_block_type(state, 1245 next_block)); 1246 } 1247 next_block->logical_bytenr = next_bytenr; 1248 1249 next_block->mirror_num = *mirror_nump; 1250 l = btrfsic_block_link_hashtable_lookup( 1251 next_block_ctx->dev->bdev, 1252 next_block_ctx->dev_bytenr, 1253 block_ctx->dev->bdev, 1254 block_ctx->dev_bytenr, 1255 &state->block_link_hashtable); 1256 } 1257 1258 next_block->disk_key = *disk_key; 1259 if (NULL == l) { 1260 l = btrfsic_block_link_alloc(); 1261 if (NULL == l) { 1262 btrfsic_release_block_ctx(next_block_ctx); 1263 *next_blockp = NULL; 1264 return -1; 1265 } 1266 1267 did_alloc_block_link = 1; 1268 l->block_ref_to = next_block; 1269 l->block_ref_from = block; 1270 l->ref_cnt = 1; 1271 l->parent_generation = parent_generation; 1272 1273 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1274 btrfsic_print_add_link(state, l); 1275 1276 list_add(&l->node_ref_to, &block->ref_to_list); 1277 list_add(&l->node_ref_from, &next_block->ref_from_list); 1278 1279 btrfsic_block_link_hashtable_add(l, 1280 &state->block_link_hashtable); 1281 } else { 1282 did_alloc_block_link = 0; 1283 if (0 == limit_nesting) { 1284 l->ref_cnt++; 1285 l->parent_generation = parent_generation; 1286 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1287 btrfsic_print_add_link(state, l); 1288 } 1289 } 1290 1291 if (limit_nesting > 0 && did_alloc_block_link) { 1292 ret = btrfsic_read_block(state, next_block_ctx); 1293 if (ret < (int)next_block_ctx->len) { 1294 pr_info("btrfsic: read block @logical %llu failed!\n", 1295 next_bytenr); 1296 btrfsic_release_block_ctx(next_block_ctx); 1297 *next_blockp = NULL; 1298 return -1; 1299 } 1300 1301 *next_blockp = next_block; 1302 } else { 1303 *next_blockp = NULL; 1304 } 1305 (*mirror_nump)++; 1306 1307 return 0; 1308 } 1309 1310 static int btrfsic_handle_extent_data( 1311 struct btrfsic_state *state, 1312 struct btrfsic_block *block, 1313 struct btrfsic_block_data_ctx *block_ctx, 1314 u32 item_offset, int force_iodone_flag) 1315 { 1316 struct btrfs_fs_info *fs_info = state->fs_info; 1317 struct btrfs_file_extent_item file_extent_item; 1318 u64 file_extent_item_offset; 1319 u64 next_bytenr; 1320 u64 num_bytes; 1321 u64 generation; 1322 struct btrfsic_block_link *l; 1323 int ret; 1324 1325 file_extent_item_offset = offsetof(struct btrfs_leaf, items) + 1326 item_offset; 1327 if (file_extent_item_offset + 1328 offsetof(struct btrfs_file_extent_item, disk_num_bytes) > 1329 block_ctx->len) { 1330 pr_info("btrfsic: file item out of bounce at logical %llu, dev %pg\n", 1331 block_ctx->start, block_ctx->dev->bdev); 1332 return -1; 1333 } 1334 1335 btrfsic_read_from_block_data(block_ctx, &file_extent_item, 1336 file_extent_item_offset, 1337 offsetof(struct btrfs_file_extent_item, disk_num_bytes)); 1338 if (BTRFS_FILE_EXTENT_REG != file_extent_item.type || 1339 btrfs_stack_file_extent_disk_bytenr(&file_extent_item) == 0) { 1340 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE) 1341 pr_info("extent_data: type %u, disk_bytenr = %llu\n", 1342 file_extent_item.type, 1343 btrfs_stack_file_extent_disk_bytenr( 1344 &file_extent_item)); 1345 return 0; 1346 } 1347 1348 if (file_extent_item_offset + sizeof(struct btrfs_file_extent_item) > 1349 block_ctx->len) { 1350 pr_info("btrfsic: file item out of bounce at logical %llu, dev %pg\n", 1351 block_ctx->start, block_ctx->dev->bdev); 1352 return -1; 1353 } 1354 btrfsic_read_from_block_data(block_ctx, &file_extent_item, 1355 file_extent_item_offset, 1356 sizeof(struct btrfs_file_extent_item)); 1357 next_bytenr = btrfs_stack_file_extent_disk_bytenr(&file_extent_item); 1358 if (btrfs_stack_file_extent_compression(&file_extent_item) == 1359 BTRFS_COMPRESS_NONE) { 1360 next_bytenr += btrfs_stack_file_extent_offset(&file_extent_item); 1361 num_bytes = btrfs_stack_file_extent_num_bytes(&file_extent_item); 1362 } else { 1363 num_bytes = btrfs_stack_file_extent_disk_num_bytes(&file_extent_item); 1364 } 1365 generation = btrfs_stack_file_extent_generation(&file_extent_item); 1366 1367 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE) 1368 pr_info("extent_data: type %u, disk_bytenr = %llu, offset = %llu, num_bytes = %llu\n", 1369 file_extent_item.type, 1370 btrfs_stack_file_extent_disk_bytenr(&file_extent_item), 1371 btrfs_stack_file_extent_offset(&file_extent_item), 1372 num_bytes); 1373 while (num_bytes > 0) { 1374 u32 chunk_len; 1375 int num_copies; 1376 int mirror_num; 1377 1378 if (num_bytes > state->datablock_size) 1379 chunk_len = state->datablock_size; 1380 else 1381 chunk_len = num_bytes; 1382 1383 num_copies = btrfs_num_copies(fs_info, next_bytenr, 1384 state->datablock_size); 1385 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 1386 pr_info("num_copies(log_bytenr=%llu) = %d\n", 1387 next_bytenr, num_copies); 1388 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 1389 struct btrfsic_block_data_ctx next_block_ctx; 1390 struct btrfsic_block *next_block; 1391 int block_was_created; 1392 1393 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1394 pr_info("btrfsic_handle_extent_data(mirror_num=%d)\n", 1395 mirror_num); 1396 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE) 1397 pr_info("\tdisk_bytenr = %llu, num_bytes %u\n", 1398 next_bytenr, chunk_len); 1399 ret = btrfsic_map_block(state, next_bytenr, 1400 chunk_len, &next_block_ctx, 1401 mirror_num); 1402 if (ret) { 1403 pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n", 1404 next_bytenr, mirror_num); 1405 return -1; 1406 } 1407 1408 next_block = btrfsic_block_lookup_or_add( 1409 state, 1410 &next_block_ctx, 1411 "referenced ", 1412 0, 1413 force_iodone_flag, 1414 !force_iodone_flag, 1415 mirror_num, 1416 &block_was_created); 1417 if (NULL == next_block) { 1418 btrfsic_release_block_ctx(&next_block_ctx); 1419 return -1; 1420 } 1421 if (!block_was_created) { 1422 if ((state->print_mask & 1423 BTRFSIC_PRINT_MASK_VERBOSE) && 1424 next_block->logical_bytenr != next_bytenr && 1425 !(!next_block->is_metadata && 1426 0 == next_block->logical_bytenr)) { 1427 pr_info( 1428 "referenced block @%llu (%pg/%llu/%d) found in hash table, D, bytenr mismatch (!= stored %llu)\n", 1429 next_bytenr, 1430 next_block_ctx.dev->bdev, 1431 next_block_ctx.dev_bytenr, 1432 mirror_num, 1433 next_block->logical_bytenr); 1434 } 1435 next_block->logical_bytenr = next_bytenr; 1436 next_block->mirror_num = mirror_num; 1437 } 1438 1439 l = btrfsic_block_link_lookup_or_add(state, 1440 &next_block_ctx, 1441 next_block, block, 1442 generation); 1443 btrfsic_release_block_ctx(&next_block_ctx); 1444 if (NULL == l) 1445 return -1; 1446 } 1447 1448 next_bytenr += chunk_len; 1449 num_bytes -= chunk_len; 1450 } 1451 1452 return 0; 1453 } 1454 1455 static int btrfsic_map_block(struct btrfsic_state *state, u64 bytenr, u32 len, 1456 struct btrfsic_block_data_ctx *block_ctx_out, 1457 int mirror_num) 1458 { 1459 struct btrfs_fs_info *fs_info = state->fs_info; 1460 int ret; 1461 u64 length; 1462 struct btrfs_io_context *multi = NULL; 1463 struct btrfs_device *device; 1464 1465 length = len; 1466 ret = btrfs_map_block(fs_info, BTRFS_MAP_READ, 1467 bytenr, &length, &multi, mirror_num); 1468 1469 if (ret) { 1470 block_ctx_out->start = 0; 1471 block_ctx_out->dev_bytenr = 0; 1472 block_ctx_out->len = 0; 1473 block_ctx_out->dev = NULL; 1474 block_ctx_out->datav = NULL; 1475 block_ctx_out->pagev = NULL; 1476 block_ctx_out->mem_to_free = NULL; 1477 1478 return ret; 1479 } 1480 1481 device = multi->stripes[0].dev; 1482 if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state) || 1483 !device->bdev || !device->name) 1484 block_ctx_out->dev = NULL; 1485 else 1486 block_ctx_out->dev = btrfsic_dev_state_lookup( 1487 device->bdev->bd_dev); 1488 block_ctx_out->dev_bytenr = multi->stripes[0].physical; 1489 block_ctx_out->start = bytenr; 1490 block_ctx_out->len = len; 1491 block_ctx_out->datav = NULL; 1492 block_ctx_out->pagev = NULL; 1493 block_ctx_out->mem_to_free = NULL; 1494 1495 kfree(multi); 1496 if (NULL == block_ctx_out->dev) { 1497 ret = -ENXIO; 1498 pr_info("btrfsic: error, cannot lookup dev (#1)!\n"); 1499 } 1500 1501 return ret; 1502 } 1503 1504 static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx) 1505 { 1506 if (block_ctx->mem_to_free) { 1507 unsigned int num_pages; 1508 1509 BUG_ON(!block_ctx->datav); 1510 BUG_ON(!block_ctx->pagev); 1511 num_pages = (block_ctx->len + (u64)PAGE_SIZE - 1) >> 1512 PAGE_SHIFT; 1513 /* Pages must be unmapped in reverse order */ 1514 while (num_pages > 0) { 1515 num_pages--; 1516 if (block_ctx->datav[num_pages]) 1517 block_ctx->datav[num_pages] = NULL; 1518 if (block_ctx->pagev[num_pages]) { 1519 __free_page(block_ctx->pagev[num_pages]); 1520 block_ctx->pagev[num_pages] = NULL; 1521 } 1522 } 1523 1524 kfree(block_ctx->mem_to_free); 1525 block_ctx->mem_to_free = NULL; 1526 block_ctx->pagev = NULL; 1527 block_ctx->datav = NULL; 1528 } 1529 } 1530 1531 static int btrfsic_read_block(struct btrfsic_state *state, 1532 struct btrfsic_block_data_ctx *block_ctx) 1533 { 1534 unsigned int num_pages; 1535 unsigned int i; 1536 size_t size; 1537 u64 dev_bytenr; 1538 int ret; 1539 1540 BUG_ON(block_ctx->datav); 1541 BUG_ON(block_ctx->pagev); 1542 BUG_ON(block_ctx->mem_to_free); 1543 if (!PAGE_ALIGNED(block_ctx->dev_bytenr)) { 1544 pr_info("btrfsic: read_block() with unaligned bytenr %llu\n", 1545 block_ctx->dev_bytenr); 1546 return -1; 1547 } 1548 1549 num_pages = (block_ctx->len + (u64)PAGE_SIZE - 1) >> 1550 PAGE_SHIFT; 1551 size = sizeof(*block_ctx->datav) + sizeof(*block_ctx->pagev); 1552 block_ctx->mem_to_free = kcalloc(num_pages, size, GFP_NOFS); 1553 if (!block_ctx->mem_to_free) 1554 return -ENOMEM; 1555 block_ctx->datav = block_ctx->mem_to_free; 1556 block_ctx->pagev = (struct page **)(block_ctx->datav + num_pages); 1557 ret = btrfs_alloc_page_array(num_pages, block_ctx->pagev); 1558 if (ret) 1559 return ret; 1560 1561 dev_bytenr = block_ctx->dev_bytenr; 1562 for (i = 0; i < num_pages;) { 1563 struct bio *bio; 1564 unsigned int j; 1565 1566 bio = bio_alloc(block_ctx->dev->bdev, num_pages - i, 1567 REQ_OP_READ, GFP_NOFS); 1568 bio->bi_iter.bi_sector = dev_bytenr >> 9; 1569 1570 for (j = i; j < num_pages; j++) { 1571 ret = bio_add_page(bio, block_ctx->pagev[j], 1572 PAGE_SIZE, 0); 1573 if (PAGE_SIZE != ret) 1574 break; 1575 } 1576 if (j == i) { 1577 pr_info("btrfsic: error, failed to add a single page!\n"); 1578 return -1; 1579 } 1580 if (submit_bio_wait(bio)) { 1581 pr_info("btrfsic: read error at logical %llu dev %pg!\n", 1582 block_ctx->start, block_ctx->dev->bdev); 1583 bio_put(bio); 1584 return -1; 1585 } 1586 bio_put(bio); 1587 dev_bytenr += (j - i) * PAGE_SIZE; 1588 i = j; 1589 } 1590 for (i = 0; i < num_pages; i++) 1591 block_ctx->datav[i] = page_address(block_ctx->pagev[i]); 1592 1593 return block_ctx->len; 1594 } 1595 1596 static void btrfsic_dump_database(struct btrfsic_state *state) 1597 { 1598 const struct btrfsic_block *b_all; 1599 1600 BUG_ON(NULL == state); 1601 1602 pr_info("all_blocks_list:\n"); 1603 list_for_each_entry(b_all, &state->all_blocks_list, all_blocks_node) { 1604 const struct btrfsic_block_link *l; 1605 1606 pr_info("%c-block @%llu (%pg/%llu/%d)\n", 1607 btrfsic_get_block_type(state, b_all), 1608 b_all->logical_bytenr, b_all->dev_state->bdev, 1609 b_all->dev_bytenr, b_all->mirror_num); 1610 1611 list_for_each_entry(l, &b_all->ref_to_list, node_ref_to) { 1612 pr_info( 1613 " %c @%llu (%pg/%llu/%d) refers %u* to %c @%llu (%pg/%llu/%d)\n", 1614 btrfsic_get_block_type(state, b_all), 1615 b_all->logical_bytenr, b_all->dev_state->bdev, 1616 b_all->dev_bytenr, b_all->mirror_num, 1617 l->ref_cnt, 1618 btrfsic_get_block_type(state, l->block_ref_to), 1619 l->block_ref_to->logical_bytenr, 1620 l->block_ref_to->dev_state->bdev, 1621 l->block_ref_to->dev_bytenr, 1622 l->block_ref_to->mirror_num); 1623 } 1624 1625 list_for_each_entry(l, &b_all->ref_from_list, node_ref_from) { 1626 pr_info( 1627 " %c @%llu (%pg/%llu/%d) is ref %u* from %c @%llu (%pg/%llu/%d)\n", 1628 btrfsic_get_block_type(state, b_all), 1629 b_all->logical_bytenr, b_all->dev_state->bdev, 1630 b_all->dev_bytenr, b_all->mirror_num, 1631 l->ref_cnt, 1632 btrfsic_get_block_type(state, l->block_ref_from), 1633 l->block_ref_from->logical_bytenr, 1634 l->block_ref_from->dev_state->bdev, 1635 l->block_ref_from->dev_bytenr, 1636 l->block_ref_from->mirror_num); 1637 } 1638 1639 pr_info("\n"); 1640 } 1641 } 1642 1643 /* 1644 * Test whether the disk block contains a tree block (leaf or node) 1645 * (note that this test fails for the super block) 1646 */ 1647 static noinline_for_stack int btrfsic_test_for_metadata( 1648 struct btrfsic_state *state, 1649 char **datav, unsigned int num_pages) 1650 { 1651 struct btrfs_fs_info *fs_info = state->fs_info; 1652 SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); 1653 struct btrfs_header *h; 1654 u8 csum[BTRFS_CSUM_SIZE]; 1655 unsigned int i; 1656 1657 if (num_pages * PAGE_SIZE < state->metablock_size) 1658 return 1; /* not metadata */ 1659 num_pages = state->metablock_size >> PAGE_SHIFT; 1660 h = (struct btrfs_header *)datav[0]; 1661 1662 if (memcmp(h->fsid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE)) 1663 return 1; 1664 1665 shash->tfm = fs_info->csum_shash; 1666 crypto_shash_init(shash); 1667 1668 for (i = 0; i < num_pages; i++) { 1669 u8 *data = i ? datav[i] : (datav[i] + BTRFS_CSUM_SIZE); 1670 size_t sublen = i ? PAGE_SIZE : 1671 (PAGE_SIZE - BTRFS_CSUM_SIZE); 1672 1673 crypto_shash_update(shash, data, sublen); 1674 } 1675 crypto_shash_final(shash, csum); 1676 if (memcmp(csum, h->csum, fs_info->csum_size)) 1677 return 1; 1678 1679 return 0; /* is metadata */ 1680 } 1681 1682 static void btrfsic_process_written_block(struct btrfsic_dev_state *dev_state, 1683 u64 dev_bytenr, char **mapped_datav, 1684 unsigned int num_pages, 1685 struct bio *bio, int *bio_is_patched, 1686 blk_opf_t submit_bio_bh_rw) 1687 { 1688 int is_metadata; 1689 struct btrfsic_block *block; 1690 struct btrfsic_block_data_ctx block_ctx; 1691 int ret; 1692 struct btrfsic_state *state = dev_state->state; 1693 struct block_device *bdev = dev_state->bdev; 1694 unsigned int processed_len; 1695 1696 if (NULL != bio_is_patched) 1697 *bio_is_patched = 0; 1698 1699 again: 1700 if (num_pages == 0) 1701 return; 1702 1703 processed_len = 0; 1704 is_metadata = (0 == btrfsic_test_for_metadata(state, mapped_datav, 1705 num_pages)); 1706 1707 block = btrfsic_block_hashtable_lookup(bdev, dev_bytenr, 1708 &state->block_hashtable); 1709 if (NULL != block) { 1710 u64 bytenr = 0; 1711 struct btrfsic_block_link *l, *tmp; 1712 1713 if (block->is_superblock) { 1714 bytenr = btrfs_super_bytenr((struct btrfs_super_block *) 1715 mapped_datav[0]); 1716 if (num_pages * PAGE_SIZE < 1717 BTRFS_SUPER_INFO_SIZE) { 1718 pr_info("btrfsic: cannot work with too short bios!\n"); 1719 return; 1720 } 1721 is_metadata = 1; 1722 BUG_ON(!PAGE_ALIGNED(BTRFS_SUPER_INFO_SIZE)); 1723 processed_len = BTRFS_SUPER_INFO_SIZE; 1724 if (state->print_mask & 1725 BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE) { 1726 pr_info("[before new superblock is written]:\n"); 1727 btrfsic_dump_tree_sub(state, block, 0); 1728 } 1729 } 1730 if (is_metadata) { 1731 if (!block->is_superblock) { 1732 if (num_pages * PAGE_SIZE < 1733 state->metablock_size) { 1734 pr_info("btrfsic: cannot work with too short bios!\n"); 1735 return; 1736 } 1737 processed_len = state->metablock_size; 1738 bytenr = btrfs_stack_header_bytenr( 1739 (struct btrfs_header *) 1740 mapped_datav[0]); 1741 btrfsic_cmp_log_and_dev_bytenr(state, bytenr, 1742 dev_state, 1743 dev_bytenr); 1744 } 1745 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) { 1746 if (block->logical_bytenr != bytenr && 1747 !(!block->is_metadata && 1748 block->logical_bytenr == 0)) 1749 pr_info( 1750 "written block @%llu (%pg/%llu/%d) found in hash table, %c, bytenr mismatch (!= stored %llu)\n", 1751 bytenr, dev_state->bdev, 1752 dev_bytenr, 1753 block->mirror_num, 1754 btrfsic_get_block_type(state, 1755 block), 1756 block->logical_bytenr); 1757 else 1758 pr_info( 1759 "written block @%llu (%pg/%llu/%d) found in hash table, %c\n", 1760 bytenr, dev_state->bdev, 1761 dev_bytenr, block->mirror_num, 1762 btrfsic_get_block_type(state, 1763 block)); 1764 } 1765 block->logical_bytenr = bytenr; 1766 } else { 1767 if (num_pages * PAGE_SIZE < 1768 state->datablock_size) { 1769 pr_info("btrfsic: cannot work with too short bios!\n"); 1770 return; 1771 } 1772 processed_len = state->datablock_size; 1773 bytenr = block->logical_bytenr; 1774 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1775 pr_info( 1776 "written block @%llu (%pg/%llu/%d) found in hash table, %c\n", 1777 bytenr, dev_state->bdev, dev_bytenr, 1778 block->mirror_num, 1779 btrfsic_get_block_type(state, block)); 1780 } 1781 1782 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1783 pr_info("ref_to_list: %cE, ref_from_list: %cE\n", 1784 list_empty(&block->ref_to_list) ? ' ' : '!', 1785 list_empty(&block->ref_from_list) ? ' ' : '!'); 1786 if (btrfsic_is_block_ref_by_superblock(state, block, 0)) { 1787 pr_info( 1788 "btrfs: attempt to overwrite %c-block @%llu (%pg/%llu/%d), old(gen=%llu, objectid=%llu, type=%d, offset=%llu), new(gen=%llu), which is referenced by most recent superblock (superblockgen=%llu)!\n", 1789 btrfsic_get_block_type(state, block), bytenr, 1790 dev_state->bdev, dev_bytenr, block->mirror_num, 1791 block->generation, 1792 btrfs_disk_key_objectid(&block->disk_key), 1793 block->disk_key.type, 1794 btrfs_disk_key_offset(&block->disk_key), 1795 btrfs_stack_header_generation( 1796 (struct btrfs_header *) mapped_datav[0]), 1797 state->max_superblock_generation); 1798 btrfsic_dump_tree(state); 1799 } 1800 1801 if (!block->is_iodone && !block->never_written) { 1802 pr_info( 1803 "btrfs: attempt to overwrite %c-block @%llu (%pg/%llu/%d), oldgen=%llu, newgen=%llu, which is not yet iodone!\n", 1804 btrfsic_get_block_type(state, block), bytenr, 1805 dev_state->bdev, dev_bytenr, block->mirror_num, 1806 block->generation, 1807 btrfs_stack_header_generation( 1808 (struct btrfs_header *) 1809 mapped_datav[0])); 1810 /* it would not be safe to go on */ 1811 btrfsic_dump_tree(state); 1812 goto continue_loop; 1813 } 1814 1815 /* 1816 * Clear all references of this block. Do not free 1817 * the block itself even if is not referenced anymore 1818 * because it still carries valuable information 1819 * like whether it was ever written and IO completed. 1820 */ 1821 list_for_each_entry_safe(l, tmp, &block->ref_to_list, 1822 node_ref_to) { 1823 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1824 btrfsic_print_rem_link(state, l); 1825 l->ref_cnt--; 1826 if (0 == l->ref_cnt) { 1827 list_del(&l->node_ref_to); 1828 list_del(&l->node_ref_from); 1829 btrfsic_block_link_hashtable_remove(l); 1830 btrfsic_block_link_free(l); 1831 } 1832 } 1833 1834 block_ctx.dev = dev_state; 1835 block_ctx.dev_bytenr = dev_bytenr; 1836 block_ctx.start = bytenr; 1837 block_ctx.len = processed_len; 1838 block_ctx.pagev = NULL; 1839 block_ctx.mem_to_free = NULL; 1840 block_ctx.datav = mapped_datav; 1841 1842 if (is_metadata || state->include_extent_data) { 1843 block->never_written = 0; 1844 block->iodone_w_error = 0; 1845 if (NULL != bio) { 1846 block->is_iodone = 0; 1847 BUG_ON(NULL == bio_is_patched); 1848 if (!*bio_is_patched) { 1849 block->orig_bio_private = 1850 bio->bi_private; 1851 block->orig_bio_end_io = 1852 bio->bi_end_io; 1853 block->next_in_same_bio = NULL; 1854 bio->bi_private = block; 1855 bio->bi_end_io = btrfsic_bio_end_io; 1856 *bio_is_patched = 1; 1857 } else { 1858 struct btrfsic_block *chained_block = 1859 (struct btrfsic_block *) 1860 bio->bi_private; 1861 1862 BUG_ON(NULL == chained_block); 1863 block->orig_bio_private = 1864 chained_block->orig_bio_private; 1865 block->orig_bio_end_io = 1866 chained_block->orig_bio_end_io; 1867 block->next_in_same_bio = chained_block; 1868 bio->bi_private = block; 1869 } 1870 } else { 1871 block->is_iodone = 1; 1872 block->orig_bio_private = NULL; 1873 block->orig_bio_end_io = NULL; 1874 block->next_in_same_bio = NULL; 1875 } 1876 } 1877 1878 block->flush_gen = dev_state->last_flush_gen + 1; 1879 block->submit_bio_bh_rw = submit_bio_bh_rw; 1880 if (is_metadata) { 1881 block->logical_bytenr = bytenr; 1882 block->is_metadata = 1; 1883 if (block->is_superblock) { 1884 BUG_ON(PAGE_SIZE != 1885 BTRFS_SUPER_INFO_SIZE); 1886 ret = btrfsic_process_written_superblock( 1887 state, 1888 block, 1889 (struct btrfs_super_block *) 1890 mapped_datav[0]); 1891 if (state->print_mask & 1892 BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE) { 1893 pr_info("[after new superblock is written]:\n"); 1894 btrfsic_dump_tree_sub(state, block, 0); 1895 } 1896 } else { 1897 block->mirror_num = 0; /* unknown */ 1898 ret = btrfsic_process_metablock( 1899 state, 1900 block, 1901 &block_ctx, 1902 0, 0); 1903 } 1904 if (ret) 1905 pr_info("btrfsic: btrfsic_process_metablock(root @%llu) failed!\n", 1906 dev_bytenr); 1907 } else { 1908 block->is_metadata = 0; 1909 block->mirror_num = 0; /* unknown */ 1910 block->generation = BTRFSIC_GENERATION_UNKNOWN; 1911 if (!state->include_extent_data 1912 && list_empty(&block->ref_from_list)) { 1913 /* 1914 * disk block is overwritten with extent 1915 * data (not meta data) and we are configured 1916 * to not include extent data: take the 1917 * chance and free the block's memory 1918 */ 1919 btrfsic_block_hashtable_remove(block); 1920 list_del(&block->all_blocks_node); 1921 btrfsic_block_free(block); 1922 } 1923 } 1924 btrfsic_release_block_ctx(&block_ctx); 1925 } else { 1926 /* block has not been found in hash table */ 1927 u64 bytenr; 1928 1929 if (!is_metadata) { 1930 processed_len = state->datablock_size; 1931 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1932 pr_info( 1933 "written block (%pg/%llu/?) !found in hash table, D\n", 1934 dev_state->bdev, dev_bytenr); 1935 if (!state->include_extent_data) { 1936 /* ignore that written D block */ 1937 goto continue_loop; 1938 } 1939 1940 /* this is getting ugly for the 1941 * include_extent_data case... */ 1942 bytenr = 0; /* unknown */ 1943 } else { 1944 processed_len = state->metablock_size; 1945 bytenr = btrfs_stack_header_bytenr( 1946 (struct btrfs_header *) 1947 mapped_datav[0]); 1948 btrfsic_cmp_log_and_dev_bytenr(state, bytenr, dev_state, 1949 dev_bytenr); 1950 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1951 pr_info( 1952 "written block @%llu (%pg/%llu/?) !found in hash table, M\n", 1953 bytenr, dev_state->bdev, dev_bytenr); 1954 } 1955 1956 block_ctx.dev = dev_state; 1957 block_ctx.dev_bytenr = dev_bytenr; 1958 block_ctx.start = bytenr; 1959 block_ctx.len = processed_len; 1960 block_ctx.pagev = NULL; 1961 block_ctx.mem_to_free = NULL; 1962 block_ctx.datav = mapped_datav; 1963 1964 block = btrfsic_block_alloc(); 1965 if (NULL == block) { 1966 btrfsic_release_block_ctx(&block_ctx); 1967 goto continue_loop; 1968 } 1969 block->dev_state = dev_state; 1970 block->dev_bytenr = dev_bytenr; 1971 block->logical_bytenr = bytenr; 1972 block->is_metadata = is_metadata; 1973 block->never_written = 0; 1974 block->iodone_w_error = 0; 1975 block->mirror_num = 0; /* unknown */ 1976 block->flush_gen = dev_state->last_flush_gen + 1; 1977 block->submit_bio_bh_rw = submit_bio_bh_rw; 1978 if (NULL != bio) { 1979 block->is_iodone = 0; 1980 BUG_ON(NULL == bio_is_patched); 1981 if (!*bio_is_patched) { 1982 block->orig_bio_private = bio->bi_private; 1983 block->orig_bio_end_io = bio->bi_end_io; 1984 block->next_in_same_bio = NULL; 1985 bio->bi_private = block; 1986 bio->bi_end_io = btrfsic_bio_end_io; 1987 *bio_is_patched = 1; 1988 } else { 1989 struct btrfsic_block *chained_block = 1990 (struct btrfsic_block *) 1991 bio->bi_private; 1992 1993 BUG_ON(NULL == chained_block); 1994 block->orig_bio_private = 1995 chained_block->orig_bio_private; 1996 block->orig_bio_end_io = 1997 chained_block->orig_bio_end_io; 1998 block->next_in_same_bio = chained_block; 1999 bio->bi_private = block; 2000 } 2001 } else { 2002 block->is_iodone = 1; 2003 block->orig_bio_private = NULL; 2004 block->orig_bio_end_io = NULL; 2005 block->next_in_same_bio = NULL; 2006 } 2007 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2008 pr_info("new written %c-block @%llu (%pg/%llu/%d)\n", 2009 is_metadata ? 'M' : 'D', 2010 block->logical_bytenr, block->dev_state->bdev, 2011 block->dev_bytenr, block->mirror_num); 2012 list_add(&block->all_blocks_node, &state->all_blocks_list); 2013 btrfsic_block_hashtable_add(block, &state->block_hashtable); 2014 2015 if (is_metadata) { 2016 ret = btrfsic_process_metablock(state, block, 2017 &block_ctx, 0, 0); 2018 if (ret) 2019 pr_info("btrfsic: process_metablock(root @%llu) failed!\n", 2020 dev_bytenr); 2021 } 2022 btrfsic_release_block_ctx(&block_ctx); 2023 } 2024 2025 continue_loop: 2026 BUG_ON(!processed_len); 2027 dev_bytenr += processed_len; 2028 mapped_datav += processed_len >> PAGE_SHIFT; 2029 num_pages -= processed_len >> PAGE_SHIFT; 2030 goto again; 2031 } 2032 2033 static void btrfsic_bio_end_io(struct bio *bp) 2034 { 2035 struct btrfsic_block *block = bp->bi_private; 2036 int iodone_w_error; 2037 2038 /* mutex is not held! This is not save if IO is not yet completed 2039 * on umount */ 2040 iodone_w_error = 0; 2041 if (bp->bi_status) 2042 iodone_w_error = 1; 2043 2044 BUG_ON(NULL == block); 2045 bp->bi_private = block->orig_bio_private; 2046 bp->bi_end_io = block->orig_bio_end_io; 2047 2048 do { 2049 struct btrfsic_block *next_block; 2050 struct btrfsic_dev_state *const dev_state = block->dev_state; 2051 2052 if ((dev_state->state->print_mask & 2053 BTRFSIC_PRINT_MASK_END_IO_BIO_BH)) 2054 pr_info("bio_end_io(err=%d) for %c @%llu (%pg/%llu/%d)\n", 2055 bp->bi_status, 2056 btrfsic_get_block_type(dev_state->state, block), 2057 block->logical_bytenr, dev_state->bdev, 2058 block->dev_bytenr, block->mirror_num); 2059 next_block = block->next_in_same_bio; 2060 block->iodone_w_error = iodone_w_error; 2061 if (block->submit_bio_bh_rw & REQ_PREFLUSH) { 2062 dev_state->last_flush_gen++; 2063 if ((dev_state->state->print_mask & 2064 BTRFSIC_PRINT_MASK_END_IO_BIO_BH)) 2065 pr_info("bio_end_io() new %pg flush_gen=%llu\n", 2066 dev_state->bdev, 2067 dev_state->last_flush_gen); 2068 } 2069 if (block->submit_bio_bh_rw & REQ_FUA) 2070 block->flush_gen = 0; /* FUA completed means block is 2071 * on disk */ 2072 block->is_iodone = 1; /* for FLUSH, this releases the block */ 2073 block = next_block; 2074 } while (NULL != block); 2075 2076 bp->bi_end_io(bp); 2077 } 2078 2079 static int btrfsic_process_written_superblock( 2080 struct btrfsic_state *state, 2081 struct btrfsic_block *const superblock, 2082 struct btrfs_super_block *const super_hdr) 2083 { 2084 struct btrfs_fs_info *fs_info = state->fs_info; 2085 int pass; 2086 2087 superblock->generation = btrfs_super_generation(super_hdr); 2088 if (!(superblock->generation > state->max_superblock_generation || 2089 0 == state->max_superblock_generation)) { 2090 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE) 2091 pr_info( 2092 "btrfsic: superblock @%llu (%pg/%llu/%d) with old gen %llu <= %llu\n", 2093 superblock->logical_bytenr, 2094 superblock->dev_state->bdev, 2095 superblock->dev_bytenr, superblock->mirror_num, 2096 btrfs_super_generation(super_hdr), 2097 state->max_superblock_generation); 2098 } else { 2099 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE) 2100 pr_info( 2101 "btrfsic: got new superblock @%llu (%pg/%llu/%d) with new gen %llu > %llu\n", 2102 superblock->logical_bytenr, 2103 superblock->dev_state->bdev, 2104 superblock->dev_bytenr, superblock->mirror_num, 2105 btrfs_super_generation(super_hdr), 2106 state->max_superblock_generation); 2107 2108 state->max_superblock_generation = 2109 btrfs_super_generation(super_hdr); 2110 state->latest_superblock = superblock; 2111 } 2112 2113 for (pass = 0; pass < 3; pass++) { 2114 int ret; 2115 u64 next_bytenr; 2116 struct btrfsic_block *next_block; 2117 struct btrfsic_block_data_ctx tmp_next_block_ctx; 2118 struct btrfsic_block_link *l; 2119 int num_copies; 2120 int mirror_num; 2121 const char *additional_string = NULL; 2122 struct btrfs_disk_key tmp_disk_key = {0}; 2123 2124 btrfs_set_disk_key_objectid(&tmp_disk_key, 2125 BTRFS_ROOT_ITEM_KEY); 2126 btrfs_set_disk_key_objectid(&tmp_disk_key, 0); 2127 2128 switch (pass) { 2129 case 0: 2130 btrfs_set_disk_key_objectid(&tmp_disk_key, 2131 BTRFS_ROOT_TREE_OBJECTID); 2132 additional_string = "root "; 2133 next_bytenr = btrfs_super_root(super_hdr); 2134 if (state->print_mask & 2135 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 2136 pr_info("root@%llu\n", next_bytenr); 2137 break; 2138 case 1: 2139 btrfs_set_disk_key_objectid(&tmp_disk_key, 2140 BTRFS_CHUNK_TREE_OBJECTID); 2141 additional_string = "chunk "; 2142 next_bytenr = btrfs_super_chunk_root(super_hdr); 2143 if (state->print_mask & 2144 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 2145 pr_info("chunk@%llu\n", next_bytenr); 2146 break; 2147 case 2: 2148 btrfs_set_disk_key_objectid(&tmp_disk_key, 2149 BTRFS_TREE_LOG_OBJECTID); 2150 additional_string = "log "; 2151 next_bytenr = btrfs_super_log_root(super_hdr); 2152 if (0 == next_bytenr) 2153 continue; 2154 if (state->print_mask & 2155 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 2156 pr_info("log@%llu\n", next_bytenr); 2157 break; 2158 } 2159 2160 num_copies = btrfs_num_copies(fs_info, next_bytenr, 2161 BTRFS_SUPER_INFO_SIZE); 2162 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 2163 pr_info("num_copies(log_bytenr=%llu) = %d\n", 2164 next_bytenr, num_copies); 2165 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 2166 int was_created; 2167 2168 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2169 pr_info("btrfsic_process_written_superblock(mirror_num=%d)\n", mirror_num); 2170 ret = btrfsic_map_block(state, next_bytenr, 2171 BTRFS_SUPER_INFO_SIZE, 2172 &tmp_next_block_ctx, 2173 mirror_num); 2174 if (ret) { 2175 pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n", 2176 next_bytenr, mirror_num); 2177 return -1; 2178 } 2179 2180 next_block = btrfsic_block_lookup_or_add( 2181 state, 2182 &tmp_next_block_ctx, 2183 additional_string, 2184 1, 0, 1, 2185 mirror_num, 2186 &was_created); 2187 if (NULL == next_block) { 2188 btrfsic_release_block_ctx(&tmp_next_block_ctx); 2189 return -1; 2190 } 2191 2192 next_block->disk_key = tmp_disk_key; 2193 if (was_created) 2194 next_block->generation = 2195 BTRFSIC_GENERATION_UNKNOWN; 2196 l = btrfsic_block_link_lookup_or_add( 2197 state, 2198 &tmp_next_block_ctx, 2199 next_block, 2200 superblock, 2201 BTRFSIC_GENERATION_UNKNOWN); 2202 btrfsic_release_block_ctx(&tmp_next_block_ctx); 2203 if (NULL == l) 2204 return -1; 2205 } 2206 } 2207 2208 if (WARN_ON(-1 == btrfsic_check_all_ref_blocks(state, superblock, 0))) 2209 btrfsic_dump_tree(state); 2210 2211 return 0; 2212 } 2213 2214 static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state, 2215 struct btrfsic_block *const block, 2216 int recursion_level) 2217 { 2218 const struct btrfsic_block_link *l; 2219 int ret = 0; 2220 2221 if (recursion_level >= 3 + BTRFS_MAX_LEVEL) { 2222 /* 2223 * Note that this situation can happen and does not 2224 * indicate an error in regular cases. It happens 2225 * when disk blocks are freed and later reused. 2226 * The check-integrity module is not aware of any 2227 * block free operations, it just recognizes block 2228 * write operations. Therefore it keeps the linkage 2229 * information for a block until a block is 2230 * rewritten. This can temporarily cause incorrect 2231 * and even circular linkage information. This 2232 * causes no harm unless such blocks are referenced 2233 * by the most recent super block. 2234 */ 2235 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2236 pr_info("btrfsic: abort cyclic linkage (case 1).\n"); 2237 2238 return ret; 2239 } 2240 2241 /* 2242 * This algorithm is recursive because the amount of used stack 2243 * space is very small and the max recursion depth is limited. 2244 */ 2245 list_for_each_entry(l, &block->ref_to_list, node_ref_to) { 2246 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2247 pr_info( 2248 "rl=%d, %c @%llu (%pg/%llu/%d) %u* refers to %c @%llu (%pg/%llu/%d)\n", 2249 recursion_level, 2250 btrfsic_get_block_type(state, block), 2251 block->logical_bytenr, block->dev_state->bdev, 2252 block->dev_bytenr, block->mirror_num, 2253 l->ref_cnt, 2254 btrfsic_get_block_type(state, l->block_ref_to), 2255 l->block_ref_to->logical_bytenr, 2256 l->block_ref_to->dev_state->bdev, 2257 l->block_ref_to->dev_bytenr, 2258 l->block_ref_to->mirror_num); 2259 if (l->block_ref_to->never_written) { 2260 pr_info( 2261 "btrfs: attempt to write superblock which references block %c @%llu (%pg/%llu/%d) which is never written!\n", 2262 btrfsic_get_block_type(state, l->block_ref_to), 2263 l->block_ref_to->logical_bytenr, 2264 l->block_ref_to->dev_state->bdev, 2265 l->block_ref_to->dev_bytenr, 2266 l->block_ref_to->mirror_num); 2267 ret = -1; 2268 } else if (!l->block_ref_to->is_iodone) { 2269 pr_info( 2270 "btrfs: attempt to write superblock which references block %c @%llu (%pg/%llu/%d) which is not yet iodone!\n", 2271 btrfsic_get_block_type(state, l->block_ref_to), 2272 l->block_ref_to->logical_bytenr, 2273 l->block_ref_to->dev_state->bdev, 2274 l->block_ref_to->dev_bytenr, 2275 l->block_ref_to->mirror_num); 2276 ret = -1; 2277 } else if (l->block_ref_to->iodone_w_error) { 2278 pr_info( 2279 "btrfs: attempt to write superblock which references block %c @%llu (%pg/%llu/%d) which has write error!\n", 2280 btrfsic_get_block_type(state, l->block_ref_to), 2281 l->block_ref_to->logical_bytenr, 2282 l->block_ref_to->dev_state->bdev, 2283 l->block_ref_to->dev_bytenr, 2284 l->block_ref_to->mirror_num); 2285 ret = -1; 2286 } else if (l->parent_generation != 2287 l->block_ref_to->generation && 2288 BTRFSIC_GENERATION_UNKNOWN != 2289 l->parent_generation && 2290 BTRFSIC_GENERATION_UNKNOWN != 2291 l->block_ref_to->generation) { 2292 pr_info( 2293 "btrfs: attempt to write superblock which references block %c @%llu (%pg/%llu/%d) with generation %llu != parent generation %llu!\n", 2294 btrfsic_get_block_type(state, l->block_ref_to), 2295 l->block_ref_to->logical_bytenr, 2296 l->block_ref_to->dev_state->bdev, 2297 l->block_ref_to->dev_bytenr, 2298 l->block_ref_to->mirror_num, 2299 l->block_ref_to->generation, 2300 l->parent_generation); 2301 ret = -1; 2302 } else if (l->block_ref_to->flush_gen > 2303 l->block_ref_to->dev_state->last_flush_gen) { 2304 pr_info( 2305 "btrfs: attempt to write superblock which references block %c @%llu (%pg/%llu/%d) which is not flushed out of disk's write cache (block flush_gen=%llu, dev->flush_gen=%llu)!\n", 2306 btrfsic_get_block_type(state, l->block_ref_to), 2307 l->block_ref_to->logical_bytenr, 2308 l->block_ref_to->dev_state->bdev, 2309 l->block_ref_to->dev_bytenr, 2310 l->block_ref_to->mirror_num, block->flush_gen, 2311 l->block_ref_to->dev_state->last_flush_gen); 2312 ret = -1; 2313 } else if (-1 == btrfsic_check_all_ref_blocks(state, 2314 l->block_ref_to, 2315 recursion_level + 2316 1)) { 2317 ret = -1; 2318 } 2319 } 2320 2321 return ret; 2322 } 2323 2324 static int btrfsic_is_block_ref_by_superblock( 2325 const struct btrfsic_state *state, 2326 const struct btrfsic_block *block, 2327 int recursion_level) 2328 { 2329 const struct btrfsic_block_link *l; 2330 2331 if (recursion_level >= 3 + BTRFS_MAX_LEVEL) { 2332 /* refer to comment at "abort cyclic linkage (case 1)" */ 2333 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2334 pr_info("btrfsic: abort cyclic linkage (case 2).\n"); 2335 2336 return 0; 2337 } 2338 2339 /* 2340 * This algorithm is recursive because the amount of used stack space 2341 * is very small and the max recursion depth is limited. 2342 */ 2343 list_for_each_entry(l, &block->ref_from_list, node_ref_from) { 2344 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2345 pr_info( 2346 "rl=%d, %c @%llu (%pg/%llu/%d) is ref %u* from %c @%llu (%pg/%llu/%d)\n", 2347 recursion_level, 2348 btrfsic_get_block_type(state, block), 2349 block->logical_bytenr, block->dev_state->bdev, 2350 block->dev_bytenr, block->mirror_num, 2351 l->ref_cnt, 2352 btrfsic_get_block_type(state, l->block_ref_from), 2353 l->block_ref_from->logical_bytenr, 2354 l->block_ref_from->dev_state->bdev, 2355 l->block_ref_from->dev_bytenr, 2356 l->block_ref_from->mirror_num); 2357 if (l->block_ref_from->is_superblock && 2358 state->latest_superblock->dev_bytenr == 2359 l->block_ref_from->dev_bytenr && 2360 state->latest_superblock->dev_state->bdev == 2361 l->block_ref_from->dev_state->bdev) 2362 return 1; 2363 else if (btrfsic_is_block_ref_by_superblock(state, 2364 l->block_ref_from, 2365 recursion_level + 2366 1)) 2367 return 1; 2368 } 2369 2370 return 0; 2371 } 2372 2373 static void btrfsic_print_add_link(const struct btrfsic_state *state, 2374 const struct btrfsic_block_link *l) 2375 { 2376 pr_info("add %u* link from %c @%llu (%pg/%llu/%d) to %c @%llu (%pg/%llu/%d)\n", 2377 l->ref_cnt, 2378 btrfsic_get_block_type(state, l->block_ref_from), 2379 l->block_ref_from->logical_bytenr, 2380 l->block_ref_from->dev_state->bdev, 2381 l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num, 2382 btrfsic_get_block_type(state, l->block_ref_to), 2383 l->block_ref_to->logical_bytenr, 2384 l->block_ref_to->dev_state->bdev, l->block_ref_to->dev_bytenr, 2385 l->block_ref_to->mirror_num); 2386 } 2387 2388 static void btrfsic_print_rem_link(const struct btrfsic_state *state, 2389 const struct btrfsic_block_link *l) 2390 { 2391 pr_info("rem %u* link from %c @%llu (%pg/%llu/%d) to %c @%llu (%pg/%llu/%d)\n", 2392 l->ref_cnt, 2393 btrfsic_get_block_type(state, l->block_ref_from), 2394 l->block_ref_from->logical_bytenr, 2395 l->block_ref_from->dev_state->bdev, 2396 l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num, 2397 btrfsic_get_block_type(state, l->block_ref_to), 2398 l->block_ref_to->logical_bytenr, 2399 l->block_ref_to->dev_state->bdev, l->block_ref_to->dev_bytenr, 2400 l->block_ref_to->mirror_num); 2401 } 2402 2403 static char btrfsic_get_block_type(const struct btrfsic_state *state, 2404 const struct btrfsic_block *block) 2405 { 2406 if (block->is_superblock && 2407 state->latest_superblock->dev_bytenr == block->dev_bytenr && 2408 state->latest_superblock->dev_state->bdev == block->dev_state->bdev) 2409 return 'S'; 2410 else if (block->is_superblock) 2411 return 's'; 2412 else if (block->is_metadata) 2413 return 'M'; 2414 else 2415 return 'D'; 2416 } 2417 2418 static void btrfsic_dump_tree(const struct btrfsic_state *state) 2419 { 2420 btrfsic_dump_tree_sub(state, state->latest_superblock, 0); 2421 } 2422 2423 static void btrfsic_dump_tree_sub(const struct btrfsic_state *state, 2424 const struct btrfsic_block *block, 2425 int indent_level) 2426 { 2427 const struct btrfsic_block_link *l; 2428 int indent_add; 2429 static char buf[80]; 2430 int cursor_position; 2431 2432 /* 2433 * Should better fill an on-stack buffer with a complete line and 2434 * dump it at once when it is time to print a newline character. 2435 */ 2436 2437 /* 2438 * This algorithm is recursive because the amount of used stack space 2439 * is very small and the max recursion depth is limited. 2440 */ 2441 indent_add = sprintf(buf, "%c-%llu(%pg/%llu/%u)", 2442 btrfsic_get_block_type(state, block), 2443 block->logical_bytenr, block->dev_state->bdev, 2444 block->dev_bytenr, block->mirror_num); 2445 if (indent_level + indent_add > BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) { 2446 printk("[...]\n"); 2447 return; 2448 } 2449 printk(buf); 2450 indent_level += indent_add; 2451 if (list_empty(&block->ref_to_list)) { 2452 printk("\n"); 2453 return; 2454 } 2455 if (block->mirror_num > 1 && 2456 !(state->print_mask & BTRFSIC_PRINT_MASK_TREE_WITH_ALL_MIRRORS)) { 2457 printk(" [...]\n"); 2458 return; 2459 } 2460 2461 cursor_position = indent_level; 2462 list_for_each_entry(l, &block->ref_to_list, node_ref_to) { 2463 while (cursor_position < indent_level) { 2464 printk(" "); 2465 cursor_position++; 2466 } 2467 if (l->ref_cnt > 1) 2468 indent_add = sprintf(buf, " %d*--> ", l->ref_cnt); 2469 else 2470 indent_add = sprintf(buf, " --> "); 2471 if (indent_level + indent_add > 2472 BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) { 2473 printk("[...]\n"); 2474 cursor_position = 0; 2475 continue; 2476 } 2477 2478 printk(buf); 2479 2480 btrfsic_dump_tree_sub(state, l->block_ref_to, 2481 indent_level + indent_add); 2482 cursor_position = 0; 2483 } 2484 } 2485 2486 static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add( 2487 struct btrfsic_state *state, 2488 struct btrfsic_block_data_ctx *next_block_ctx, 2489 struct btrfsic_block *next_block, 2490 struct btrfsic_block *from_block, 2491 u64 parent_generation) 2492 { 2493 struct btrfsic_block_link *l; 2494 2495 l = btrfsic_block_link_hashtable_lookup(next_block_ctx->dev->bdev, 2496 next_block_ctx->dev_bytenr, 2497 from_block->dev_state->bdev, 2498 from_block->dev_bytenr, 2499 &state->block_link_hashtable); 2500 if (NULL == l) { 2501 l = btrfsic_block_link_alloc(); 2502 if (!l) 2503 return NULL; 2504 2505 l->block_ref_to = next_block; 2506 l->block_ref_from = from_block; 2507 l->ref_cnt = 1; 2508 l->parent_generation = parent_generation; 2509 2510 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2511 btrfsic_print_add_link(state, l); 2512 2513 list_add(&l->node_ref_to, &from_block->ref_to_list); 2514 list_add(&l->node_ref_from, &next_block->ref_from_list); 2515 2516 btrfsic_block_link_hashtable_add(l, 2517 &state->block_link_hashtable); 2518 } else { 2519 l->ref_cnt++; 2520 l->parent_generation = parent_generation; 2521 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2522 btrfsic_print_add_link(state, l); 2523 } 2524 2525 return l; 2526 } 2527 2528 static struct btrfsic_block *btrfsic_block_lookup_or_add( 2529 struct btrfsic_state *state, 2530 struct btrfsic_block_data_ctx *block_ctx, 2531 const char *additional_string, 2532 int is_metadata, 2533 int is_iodone, 2534 int never_written, 2535 int mirror_num, 2536 int *was_created) 2537 { 2538 struct btrfsic_block *block; 2539 2540 block = btrfsic_block_hashtable_lookup(block_ctx->dev->bdev, 2541 block_ctx->dev_bytenr, 2542 &state->block_hashtable); 2543 if (NULL == block) { 2544 struct btrfsic_dev_state *dev_state; 2545 2546 block = btrfsic_block_alloc(); 2547 if (!block) 2548 return NULL; 2549 2550 dev_state = btrfsic_dev_state_lookup(block_ctx->dev->bdev->bd_dev); 2551 if (NULL == dev_state) { 2552 pr_info("btrfsic: error, lookup dev_state failed!\n"); 2553 btrfsic_block_free(block); 2554 return NULL; 2555 } 2556 block->dev_state = dev_state; 2557 block->dev_bytenr = block_ctx->dev_bytenr; 2558 block->logical_bytenr = block_ctx->start; 2559 block->is_metadata = is_metadata; 2560 block->is_iodone = is_iodone; 2561 block->never_written = never_written; 2562 block->mirror_num = mirror_num; 2563 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2564 pr_info("New %s%c-block @%llu (%pg/%llu/%d)\n", 2565 additional_string, 2566 btrfsic_get_block_type(state, block), 2567 block->logical_bytenr, dev_state->bdev, 2568 block->dev_bytenr, mirror_num); 2569 list_add(&block->all_blocks_node, &state->all_blocks_list); 2570 btrfsic_block_hashtable_add(block, &state->block_hashtable); 2571 if (NULL != was_created) 2572 *was_created = 1; 2573 } else { 2574 if (NULL != was_created) 2575 *was_created = 0; 2576 } 2577 2578 return block; 2579 } 2580 2581 static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state, 2582 u64 bytenr, 2583 struct btrfsic_dev_state *dev_state, 2584 u64 dev_bytenr) 2585 { 2586 struct btrfs_fs_info *fs_info = state->fs_info; 2587 struct btrfsic_block_data_ctx block_ctx; 2588 int num_copies; 2589 int mirror_num; 2590 int match = 0; 2591 int ret; 2592 2593 num_copies = btrfs_num_copies(fs_info, bytenr, state->metablock_size); 2594 2595 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 2596 ret = btrfsic_map_block(state, bytenr, state->metablock_size, 2597 &block_ctx, mirror_num); 2598 if (ret) { 2599 pr_info("btrfsic: btrfsic_map_block(logical @%llu, mirror %d) failed!\n", 2600 bytenr, mirror_num); 2601 continue; 2602 } 2603 2604 if (dev_state->bdev == block_ctx.dev->bdev && 2605 dev_bytenr == block_ctx.dev_bytenr) { 2606 match++; 2607 btrfsic_release_block_ctx(&block_ctx); 2608 break; 2609 } 2610 btrfsic_release_block_ctx(&block_ctx); 2611 } 2612 2613 if (WARN_ON(!match)) { 2614 pr_info( 2615 "btrfs: attempt to write M-block which contains logical bytenr that doesn't map to dev+physical bytenr of submit_bio, buffer->log_bytenr=%llu, submit_bio(bdev=%pg, phys_bytenr=%llu)!\n", 2616 bytenr, dev_state->bdev, dev_bytenr); 2617 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 2618 ret = btrfsic_map_block(state, bytenr, 2619 state->metablock_size, 2620 &block_ctx, mirror_num); 2621 if (ret) 2622 continue; 2623 2624 pr_info("read logical bytenr @%llu maps to (%pg/%llu/%d)\n", 2625 bytenr, block_ctx.dev->bdev, 2626 block_ctx.dev_bytenr, mirror_num); 2627 } 2628 } 2629 } 2630 2631 static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev) 2632 { 2633 return btrfsic_dev_state_hashtable_lookup(dev, 2634 &btrfsic_dev_state_hashtable); 2635 } 2636 2637 static void btrfsic_check_write_bio(struct bio *bio, struct btrfsic_dev_state *dev_state) 2638 { 2639 unsigned int segs = bio_segments(bio); 2640 u64 dev_bytenr = 512 * bio->bi_iter.bi_sector; 2641 u64 cur_bytenr = dev_bytenr; 2642 struct bvec_iter iter; 2643 struct bio_vec bvec; 2644 char **mapped_datav; 2645 int bio_is_patched = 0; 2646 int i = 0; 2647 2648 if (dev_state->state->print_mask & BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH) 2649 pr_info( 2650 "submit_bio(rw=%d,0x%x, bi_vcnt=%u, bi_sector=%llu (bytenr %llu), bi_bdev=%p)\n", 2651 bio_op(bio), bio->bi_opf, segs, 2652 bio->bi_iter.bi_sector, dev_bytenr, bio->bi_bdev); 2653 2654 mapped_datav = kmalloc_array(segs, sizeof(*mapped_datav), GFP_NOFS); 2655 if (!mapped_datav) 2656 return; 2657 2658 bio_for_each_segment(bvec, bio, iter) { 2659 BUG_ON(bvec.bv_len != PAGE_SIZE); 2660 mapped_datav[i] = page_address(bvec.bv_page); 2661 i++; 2662 2663 if (dev_state->state->print_mask & 2664 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE) 2665 pr_info("#%u: bytenr=%llu, len=%u, offset=%u\n", 2666 i, cur_bytenr, bvec.bv_len, bvec.bv_offset); 2667 cur_bytenr += bvec.bv_len; 2668 } 2669 2670 btrfsic_process_written_block(dev_state, dev_bytenr, mapped_datav, segs, 2671 bio, &bio_is_patched, bio->bi_opf); 2672 kfree(mapped_datav); 2673 } 2674 2675 static void btrfsic_check_flush_bio(struct bio *bio, struct btrfsic_dev_state *dev_state) 2676 { 2677 if (dev_state->state->print_mask & BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH) 2678 pr_info("submit_bio(rw=%d,0x%x FLUSH, bdev=%p)\n", 2679 bio_op(bio), bio->bi_opf, bio->bi_bdev); 2680 2681 if (dev_state->dummy_block_for_bio_bh_flush.is_iodone) { 2682 struct btrfsic_block *const block = 2683 &dev_state->dummy_block_for_bio_bh_flush; 2684 2685 block->is_iodone = 0; 2686 block->never_written = 0; 2687 block->iodone_w_error = 0; 2688 block->flush_gen = dev_state->last_flush_gen + 1; 2689 block->submit_bio_bh_rw = bio->bi_opf; 2690 block->orig_bio_private = bio->bi_private; 2691 block->orig_bio_end_io = bio->bi_end_io; 2692 block->next_in_same_bio = NULL; 2693 bio->bi_private = block; 2694 bio->bi_end_io = btrfsic_bio_end_io; 2695 } else if ((dev_state->state->print_mask & 2696 (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH | 2697 BTRFSIC_PRINT_MASK_VERBOSE))) { 2698 pr_info( 2699 "btrfsic_submit_bio(%pg) with FLUSH but dummy block already in use (ignored)!\n", 2700 dev_state->bdev); 2701 } 2702 } 2703 2704 void btrfsic_check_bio(struct bio *bio) 2705 { 2706 struct btrfsic_dev_state *dev_state; 2707 2708 if (!btrfsic_is_initialized) 2709 return; 2710 2711 /* 2712 * We can be called before btrfsic_mount, so there might not be a 2713 * dev_state. 2714 */ 2715 dev_state = btrfsic_dev_state_lookup(bio->bi_bdev->bd_dev); 2716 mutex_lock(&btrfsic_mutex); 2717 if (dev_state) { 2718 if (bio_op(bio) == REQ_OP_WRITE && bio_has_data(bio)) 2719 btrfsic_check_write_bio(bio, dev_state); 2720 else if (bio->bi_opf & REQ_PREFLUSH) 2721 btrfsic_check_flush_bio(bio, dev_state); 2722 } 2723 mutex_unlock(&btrfsic_mutex); 2724 } 2725 2726 int btrfsic_mount(struct btrfs_fs_info *fs_info, 2727 struct btrfs_fs_devices *fs_devices, 2728 int including_extent_data, u32 print_mask) 2729 { 2730 int ret; 2731 struct btrfsic_state *state; 2732 struct list_head *dev_head = &fs_devices->devices; 2733 struct btrfs_device *device; 2734 2735 if (!PAGE_ALIGNED(fs_info->nodesize)) { 2736 pr_info("btrfsic: cannot handle nodesize %d not being a multiple of PAGE_SIZE %ld!\n", 2737 fs_info->nodesize, PAGE_SIZE); 2738 return -1; 2739 } 2740 if (!PAGE_ALIGNED(fs_info->sectorsize)) { 2741 pr_info("btrfsic: cannot handle sectorsize %d not being a multiple of PAGE_SIZE %ld!\n", 2742 fs_info->sectorsize, PAGE_SIZE); 2743 return -1; 2744 } 2745 state = kvzalloc(sizeof(*state), GFP_KERNEL); 2746 if (!state) 2747 return -ENOMEM; 2748 2749 if (!btrfsic_is_initialized) { 2750 mutex_init(&btrfsic_mutex); 2751 btrfsic_dev_state_hashtable_init(&btrfsic_dev_state_hashtable); 2752 btrfsic_is_initialized = 1; 2753 } 2754 mutex_lock(&btrfsic_mutex); 2755 state->fs_info = fs_info; 2756 state->print_mask = print_mask; 2757 state->include_extent_data = including_extent_data; 2758 state->metablock_size = fs_info->nodesize; 2759 state->datablock_size = fs_info->sectorsize; 2760 INIT_LIST_HEAD(&state->all_blocks_list); 2761 btrfsic_block_hashtable_init(&state->block_hashtable); 2762 btrfsic_block_link_hashtable_init(&state->block_link_hashtable); 2763 state->max_superblock_generation = 0; 2764 state->latest_superblock = NULL; 2765 2766 list_for_each_entry(device, dev_head, dev_list) { 2767 struct btrfsic_dev_state *ds; 2768 2769 if (!device->bdev || !device->name) 2770 continue; 2771 2772 ds = btrfsic_dev_state_alloc(); 2773 if (NULL == ds) { 2774 mutex_unlock(&btrfsic_mutex); 2775 return -ENOMEM; 2776 } 2777 ds->bdev = device->bdev; 2778 ds->state = state; 2779 btrfsic_dev_state_hashtable_add(ds, 2780 &btrfsic_dev_state_hashtable); 2781 } 2782 2783 ret = btrfsic_process_superblock(state, fs_devices); 2784 if (0 != ret) { 2785 mutex_unlock(&btrfsic_mutex); 2786 btrfsic_unmount(fs_devices); 2787 return ret; 2788 } 2789 2790 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_DATABASE) 2791 btrfsic_dump_database(state); 2792 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_TREE) 2793 btrfsic_dump_tree(state); 2794 2795 mutex_unlock(&btrfsic_mutex); 2796 return 0; 2797 } 2798 2799 void btrfsic_unmount(struct btrfs_fs_devices *fs_devices) 2800 { 2801 struct btrfsic_block *b_all, *tmp_all; 2802 struct btrfsic_state *state; 2803 struct list_head *dev_head = &fs_devices->devices; 2804 struct btrfs_device *device; 2805 2806 if (!btrfsic_is_initialized) 2807 return; 2808 2809 mutex_lock(&btrfsic_mutex); 2810 2811 state = NULL; 2812 list_for_each_entry(device, dev_head, dev_list) { 2813 struct btrfsic_dev_state *ds; 2814 2815 if (!device->bdev || !device->name) 2816 continue; 2817 2818 ds = btrfsic_dev_state_hashtable_lookup( 2819 device->bdev->bd_dev, 2820 &btrfsic_dev_state_hashtable); 2821 if (NULL != ds) { 2822 state = ds->state; 2823 btrfsic_dev_state_hashtable_remove(ds); 2824 btrfsic_dev_state_free(ds); 2825 } 2826 } 2827 2828 if (NULL == state) { 2829 pr_info("btrfsic: error, cannot find state information on umount!\n"); 2830 mutex_unlock(&btrfsic_mutex); 2831 return; 2832 } 2833 2834 /* 2835 * Don't care about keeping the lists' state up to date, 2836 * just free all memory that was allocated dynamically. 2837 * Free the blocks and the block_links. 2838 */ 2839 list_for_each_entry_safe(b_all, tmp_all, &state->all_blocks_list, 2840 all_blocks_node) { 2841 struct btrfsic_block_link *l, *tmp; 2842 2843 list_for_each_entry_safe(l, tmp, &b_all->ref_to_list, 2844 node_ref_to) { 2845 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2846 btrfsic_print_rem_link(state, l); 2847 2848 l->ref_cnt--; 2849 if (0 == l->ref_cnt) 2850 btrfsic_block_link_free(l); 2851 } 2852 2853 if (b_all->is_iodone || b_all->never_written) 2854 btrfsic_block_free(b_all); 2855 else 2856 pr_info( 2857 "btrfs: attempt to free %c-block @%llu (%pg/%llu/%d) on umount which is not yet iodone!\n", 2858 btrfsic_get_block_type(state, b_all), 2859 b_all->logical_bytenr, b_all->dev_state->bdev, 2860 b_all->dev_bytenr, b_all->mirror_num); 2861 } 2862 2863 mutex_unlock(&btrfsic_mutex); 2864 2865 kvfree(state); 2866 } 2867