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 "ctree.h" 86 #include "disk-io.h" 87 #include "transaction.h" 88 #include "extent_io.h" 89 #include "volumes.h" 90 #include "print-tree.h" 91 #include "locking.h" 92 #include "check-integrity.h" 93 #include "rcu-string.h" 94 #include "compression.h" 95 96 #define BTRFSIC_BLOCK_HASHTABLE_SIZE 0x10000 97 #define BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE 0x10000 98 #define BTRFSIC_DEV2STATE_HASHTABLE_SIZE 0x100 99 #define BTRFSIC_BLOCK_MAGIC_NUMBER 0x14491051 100 #define BTRFSIC_BLOCK_LINK_MAGIC_NUMBER 0x11070807 101 #define BTRFSIC_DEV2STATE_MAGIC_NUMBER 0x20111530 102 #define BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER 20111300 103 #define BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL (200 - 6) /* in characters, 104 * excluding " [...]" */ 105 #define BTRFSIC_GENERATION_UNKNOWN ((u64)-1) 106 107 /* 108 * The definition of the bitmask fields for the print_mask. 109 * They are specified with the mount option check_integrity_print_mask. 110 */ 111 #define BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE 0x00000001 112 #define BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION 0x00000002 113 #define BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE 0x00000004 114 #define BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE 0x00000008 115 #define BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH 0x00000010 116 #define BTRFSIC_PRINT_MASK_END_IO_BIO_BH 0x00000020 117 #define BTRFSIC_PRINT_MASK_VERBOSE 0x00000040 118 #define BTRFSIC_PRINT_MASK_VERY_VERBOSE 0x00000080 119 #define BTRFSIC_PRINT_MASK_INITIAL_TREE 0x00000100 120 #define BTRFSIC_PRINT_MASK_INITIAL_ALL_TREES 0x00000200 121 #define BTRFSIC_PRINT_MASK_INITIAL_DATABASE 0x00000400 122 #define BTRFSIC_PRINT_MASK_NUM_COPIES 0x00000800 123 #define BTRFSIC_PRINT_MASK_TREE_WITH_ALL_MIRRORS 0x00001000 124 #define BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE 0x00002000 125 126 struct btrfsic_dev_state; 127 struct btrfsic_state; 128 129 struct btrfsic_block { 130 u32 magic_num; /* only used for debug purposes */ 131 unsigned int is_metadata:1; /* if it is meta-data, not data-data */ 132 unsigned int is_superblock:1; /* if it is one of the superblocks */ 133 unsigned int is_iodone:1; /* if is done by lower subsystem */ 134 unsigned int iodone_w_error:1; /* error was indicated to endio */ 135 unsigned int never_written:1; /* block was added because it was 136 * referenced, not because it was 137 * written */ 138 unsigned int mirror_num; /* large enough to hold 139 * BTRFS_SUPER_MIRROR_MAX */ 140 struct btrfsic_dev_state *dev_state; 141 u64 dev_bytenr; /* key, physical byte num on disk */ 142 u64 logical_bytenr; /* logical byte num on disk */ 143 u64 generation; 144 struct btrfs_disk_key disk_key; /* extra info to print in case of 145 * issues, will not always be correct */ 146 struct list_head collision_resolving_node; /* list node */ 147 struct list_head all_blocks_node; /* list node */ 148 149 /* the following two lists contain block_link items */ 150 struct list_head ref_to_list; /* list */ 151 struct list_head ref_from_list; /* list */ 152 struct btrfsic_block *next_in_same_bio; 153 void *orig_bio_private; 154 bio_end_io_t *orig_bio_end_io; 155 int submit_bio_bh_rw; 156 u64 flush_gen; /* only valid if !never_written */ 157 }; 158 159 /* 160 * Elements of this type are allocated dynamically and required because 161 * each block object can refer to and can be ref from multiple blocks. 162 * The key to lookup them in the hashtable is the dev_bytenr of 163 * the block ref to plus the one from the block referred from. 164 * The fact that they are searchable via a hashtable and that a 165 * ref_cnt is maintained is not required for the btrfs integrity 166 * check algorithm itself, it is only used to make the output more 167 * beautiful in case that an error is detected (an error is defined 168 * as a write operation to a block while that block is still referenced). 169 */ 170 struct btrfsic_block_link { 171 u32 magic_num; /* only used for debug purposes */ 172 u32 ref_cnt; 173 struct list_head node_ref_to; /* list node */ 174 struct list_head node_ref_from; /* list node */ 175 struct list_head collision_resolving_node; /* list node */ 176 struct btrfsic_block *block_ref_to; 177 struct btrfsic_block *block_ref_from; 178 u64 parent_generation; 179 }; 180 181 struct btrfsic_dev_state { 182 u32 magic_num; /* only used for debug purposes */ 183 struct block_device *bdev; 184 struct btrfsic_state *state; 185 struct list_head collision_resolving_node; /* list node */ 186 struct btrfsic_block dummy_block_for_bio_bh_flush; 187 u64 last_flush_gen; 188 }; 189 190 struct btrfsic_block_hashtable { 191 struct list_head table[BTRFSIC_BLOCK_HASHTABLE_SIZE]; 192 }; 193 194 struct btrfsic_block_link_hashtable { 195 struct list_head table[BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE]; 196 }; 197 198 struct btrfsic_dev_state_hashtable { 199 struct list_head table[BTRFSIC_DEV2STATE_HASHTABLE_SIZE]; 200 }; 201 202 struct btrfsic_block_data_ctx { 203 u64 start; /* virtual bytenr */ 204 u64 dev_bytenr; /* physical bytenr on device */ 205 u32 len; 206 struct btrfsic_dev_state *dev; 207 char **datav; 208 struct page **pagev; 209 void *mem_to_free; 210 }; 211 212 /* This structure is used to implement recursion without occupying 213 * any stack space, refer to btrfsic_process_metablock() */ 214 struct btrfsic_stack_frame { 215 u32 magic; 216 u32 nr; 217 int error; 218 int i; 219 int limit_nesting; 220 int num_copies; 221 int mirror_num; 222 struct btrfsic_block *block; 223 struct btrfsic_block_data_ctx *block_ctx; 224 struct btrfsic_block *next_block; 225 struct btrfsic_block_data_ctx next_block_ctx; 226 struct btrfs_header *hdr; 227 struct btrfsic_stack_frame *prev; 228 }; 229 230 /* Some state per mounted filesystem */ 231 struct btrfsic_state { 232 u32 print_mask; 233 int include_extent_data; 234 struct list_head all_blocks_list; 235 struct btrfsic_block_hashtable block_hashtable; 236 struct btrfsic_block_link_hashtable block_link_hashtable; 237 struct btrfs_fs_info *fs_info; 238 u64 max_superblock_generation; 239 struct btrfsic_block *latest_superblock; 240 u32 metablock_size; 241 u32 datablock_size; 242 }; 243 244 static int btrfsic_process_metablock(struct btrfsic_state *state, 245 struct btrfsic_block *block, 246 struct btrfsic_block_data_ctx *block_ctx, 247 int limit_nesting, int force_iodone_flag); 248 static void btrfsic_read_from_block_data( 249 struct btrfsic_block_data_ctx *block_ctx, 250 void *dst, u32 offset, size_t len); 251 static int btrfsic_create_link_to_next_block( 252 struct btrfsic_state *state, 253 struct btrfsic_block *block, 254 struct btrfsic_block_data_ctx 255 *block_ctx, u64 next_bytenr, 256 int limit_nesting, 257 struct btrfsic_block_data_ctx *next_block_ctx, 258 struct btrfsic_block **next_blockp, 259 int force_iodone_flag, 260 int *num_copiesp, int *mirror_nump, 261 struct btrfs_disk_key *disk_key, 262 u64 parent_generation); 263 static int btrfsic_handle_extent_data(struct btrfsic_state *state, 264 struct btrfsic_block *block, 265 struct btrfsic_block_data_ctx *block_ctx, 266 u32 item_offset, int force_iodone_flag); 267 static int btrfsic_map_block(struct btrfsic_state *state, u64 bytenr, u32 len, 268 struct btrfsic_block_data_ctx *block_ctx_out, 269 int mirror_num); 270 static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx); 271 static int btrfsic_read_block(struct btrfsic_state *state, 272 struct btrfsic_block_data_ctx *block_ctx); 273 static int btrfsic_process_written_superblock( 274 struct btrfsic_state *state, 275 struct btrfsic_block *const block, 276 struct btrfs_super_block *const super_hdr); 277 static void btrfsic_bio_end_io(struct bio *bp); 278 static int btrfsic_is_block_ref_by_superblock(const struct btrfsic_state *state, 279 const struct btrfsic_block *block, 280 int recursion_level); 281 static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state, 282 struct btrfsic_block *const block, 283 int recursion_level); 284 static void btrfsic_print_add_link(const struct btrfsic_state *state, 285 const struct btrfsic_block_link *l); 286 static void btrfsic_print_rem_link(const struct btrfsic_state *state, 287 const struct btrfsic_block_link *l); 288 static char btrfsic_get_block_type(const struct btrfsic_state *state, 289 const struct btrfsic_block *block); 290 static void btrfsic_dump_tree(const struct btrfsic_state *state); 291 static void btrfsic_dump_tree_sub(const struct btrfsic_state *state, 292 const struct btrfsic_block *block, 293 int indent_level); 294 static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add( 295 struct btrfsic_state *state, 296 struct btrfsic_block_data_ctx *next_block_ctx, 297 struct btrfsic_block *next_block, 298 struct btrfsic_block *from_block, 299 u64 parent_generation); 300 static struct btrfsic_block *btrfsic_block_lookup_or_add( 301 struct btrfsic_state *state, 302 struct btrfsic_block_data_ctx *block_ctx, 303 const char *additional_string, 304 int is_metadata, 305 int is_iodone, 306 int never_written, 307 int mirror_num, 308 int *was_created); 309 static int btrfsic_process_superblock_dev_mirror( 310 struct btrfsic_state *state, 311 struct btrfsic_dev_state *dev_state, 312 struct btrfs_device *device, 313 int superblock_mirror_num, 314 struct btrfsic_dev_state **selected_dev_state, 315 struct btrfs_super_block *selected_super); 316 static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev); 317 static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state, 318 u64 bytenr, 319 struct btrfsic_dev_state *dev_state, 320 u64 dev_bytenr); 321 322 static struct mutex btrfsic_mutex; 323 static int btrfsic_is_initialized; 324 static struct btrfsic_dev_state_hashtable btrfsic_dev_state_hashtable; 325 326 327 static void btrfsic_block_init(struct btrfsic_block *b) 328 { 329 b->magic_num = BTRFSIC_BLOCK_MAGIC_NUMBER; 330 b->dev_state = NULL; 331 b->dev_bytenr = 0; 332 b->logical_bytenr = 0; 333 b->generation = BTRFSIC_GENERATION_UNKNOWN; 334 b->disk_key.objectid = 0; 335 b->disk_key.type = 0; 336 b->disk_key.offset = 0; 337 b->is_metadata = 0; 338 b->is_superblock = 0; 339 b->is_iodone = 0; 340 b->iodone_w_error = 0; 341 b->never_written = 0; 342 b->mirror_num = 0; 343 b->next_in_same_bio = NULL; 344 b->orig_bio_private = NULL; 345 b->orig_bio_end_io = NULL; 346 INIT_LIST_HEAD(&b->collision_resolving_node); 347 INIT_LIST_HEAD(&b->all_blocks_node); 348 INIT_LIST_HEAD(&b->ref_to_list); 349 INIT_LIST_HEAD(&b->ref_from_list); 350 b->submit_bio_bh_rw = 0; 351 b->flush_gen = 0; 352 } 353 354 static struct btrfsic_block *btrfsic_block_alloc(void) 355 { 356 struct btrfsic_block *b; 357 358 b = kzalloc(sizeof(*b), GFP_NOFS); 359 if (NULL != b) 360 btrfsic_block_init(b); 361 362 return b; 363 } 364 365 static void btrfsic_block_free(struct btrfsic_block *b) 366 { 367 BUG_ON(!(NULL == b || BTRFSIC_BLOCK_MAGIC_NUMBER == b->magic_num)); 368 kfree(b); 369 } 370 371 static void btrfsic_block_link_init(struct btrfsic_block_link *l) 372 { 373 l->magic_num = BTRFSIC_BLOCK_LINK_MAGIC_NUMBER; 374 l->ref_cnt = 1; 375 INIT_LIST_HEAD(&l->node_ref_to); 376 INIT_LIST_HEAD(&l->node_ref_from); 377 INIT_LIST_HEAD(&l->collision_resolving_node); 378 l->block_ref_to = NULL; 379 l->block_ref_from = NULL; 380 } 381 382 static struct btrfsic_block_link *btrfsic_block_link_alloc(void) 383 { 384 struct btrfsic_block_link *l; 385 386 l = kzalloc(sizeof(*l), GFP_NOFS); 387 if (NULL != l) 388 btrfsic_block_link_init(l); 389 390 return l; 391 } 392 393 static void btrfsic_block_link_free(struct btrfsic_block_link *l) 394 { 395 BUG_ON(!(NULL == l || BTRFSIC_BLOCK_LINK_MAGIC_NUMBER == l->magic_num)); 396 kfree(l); 397 } 398 399 static void btrfsic_dev_state_init(struct btrfsic_dev_state *ds) 400 { 401 ds->magic_num = BTRFSIC_DEV2STATE_MAGIC_NUMBER; 402 ds->bdev = NULL; 403 ds->state = NULL; 404 INIT_LIST_HEAD(&ds->collision_resolving_node); 405 ds->last_flush_gen = 0; 406 btrfsic_block_init(&ds->dummy_block_for_bio_bh_flush); 407 ds->dummy_block_for_bio_bh_flush.is_iodone = 1; 408 ds->dummy_block_for_bio_bh_flush.dev_state = ds; 409 } 410 411 static struct btrfsic_dev_state *btrfsic_dev_state_alloc(void) 412 { 413 struct btrfsic_dev_state *ds; 414 415 ds = kzalloc(sizeof(*ds), GFP_NOFS); 416 if (NULL != ds) 417 btrfsic_dev_state_init(ds); 418 419 return ds; 420 } 421 422 static void btrfsic_dev_state_free(struct btrfsic_dev_state *ds) 423 { 424 BUG_ON(!(NULL == ds || 425 BTRFSIC_DEV2STATE_MAGIC_NUMBER == ds->magic_num)); 426 kfree(ds); 427 } 428 429 static void btrfsic_block_hashtable_init(struct btrfsic_block_hashtable *h) 430 { 431 int i; 432 433 for (i = 0; i < BTRFSIC_BLOCK_HASHTABLE_SIZE; i++) 434 INIT_LIST_HEAD(h->table + i); 435 } 436 437 static void btrfsic_block_hashtable_add(struct btrfsic_block *b, 438 struct btrfsic_block_hashtable *h) 439 { 440 const unsigned int hashval = 441 (((unsigned int)(b->dev_bytenr >> 16)) ^ 442 ((unsigned int)((uintptr_t)b->dev_state->bdev))) & 443 (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1); 444 445 list_add(&b->collision_resolving_node, h->table + hashval); 446 } 447 448 static void btrfsic_block_hashtable_remove(struct btrfsic_block *b) 449 { 450 list_del(&b->collision_resolving_node); 451 } 452 453 static struct btrfsic_block *btrfsic_block_hashtable_lookup( 454 struct block_device *bdev, 455 u64 dev_bytenr, 456 struct btrfsic_block_hashtable *h) 457 { 458 const unsigned int hashval = 459 (((unsigned int)(dev_bytenr >> 16)) ^ 460 ((unsigned int)((uintptr_t)bdev))) & 461 (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1); 462 struct btrfsic_block *b; 463 464 list_for_each_entry(b, h->table + hashval, collision_resolving_node) { 465 if (b->dev_state->bdev == bdev && b->dev_bytenr == dev_bytenr) 466 return b; 467 } 468 469 return NULL; 470 } 471 472 static void btrfsic_block_link_hashtable_init( 473 struct btrfsic_block_link_hashtable *h) 474 { 475 int i; 476 477 for (i = 0; i < BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE; i++) 478 INIT_LIST_HEAD(h->table + i); 479 } 480 481 static void btrfsic_block_link_hashtable_add( 482 struct btrfsic_block_link *l, 483 struct btrfsic_block_link_hashtable *h) 484 { 485 const unsigned int hashval = 486 (((unsigned int)(l->block_ref_to->dev_bytenr >> 16)) ^ 487 ((unsigned int)(l->block_ref_from->dev_bytenr >> 16)) ^ 488 ((unsigned int)((uintptr_t)l->block_ref_to->dev_state->bdev)) ^ 489 ((unsigned int)((uintptr_t)l->block_ref_from->dev_state->bdev))) 490 & (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1); 491 492 BUG_ON(NULL == l->block_ref_to); 493 BUG_ON(NULL == l->block_ref_from); 494 list_add(&l->collision_resolving_node, h->table + hashval); 495 } 496 497 static void btrfsic_block_link_hashtable_remove(struct btrfsic_block_link *l) 498 { 499 list_del(&l->collision_resolving_node); 500 } 501 502 static struct btrfsic_block_link *btrfsic_block_link_hashtable_lookup( 503 struct block_device *bdev_ref_to, 504 u64 dev_bytenr_ref_to, 505 struct block_device *bdev_ref_from, 506 u64 dev_bytenr_ref_from, 507 struct btrfsic_block_link_hashtable *h) 508 { 509 const unsigned int hashval = 510 (((unsigned int)(dev_bytenr_ref_to >> 16)) ^ 511 ((unsigned int)(dev_bytenr_ref_from >> 16)) ^ 512 ((unsigned int)((uintptr_t)bdev_ref_to)) ^ 513 ((unsigned int)((uintptr_t)bdev_ref_from))) & 514 (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1); 515 struct btrfsic_block_link *l; 516 517 list_for_each_entry(l, h->table + hashval, collision_resolving_node) { 518 BUG_ON(NULL == l->block_ref_to); 519 BUG_ON(NULL == l->block_ref_from); 520 if (l->block_ref_to->dev_state->bdev == bdev_ref_to && 521 l->block_ref_to->dev_bytenr == dev_bytenr_ref_to && 522 l->block_ref_from->dev_state->bdev == bdev_ref_from && 523 l->block_ref_from->dev_bytenr == dev_bytenr_ref_from) 524 return l; 525 } 526 527 return NULL; 528 } 529 530 static void btrfsic_dev_state_hashtable_init( 531 struct btrfsic_dev_state_hashtable *h) 532 { 533 int i; 534 535 for (i = 0; i < BTRFSIC_DEV2STATE_HASHTABLE_SIZE; i++) 536 INIT_LIST_HEAD(h->table + i); 537 } 538 539 static void btrfsic_dev_state_hashtable_add( 540 struct btrfsic_dev_state *ds, 541 struct btrfsic_dev_state_hashtable *h) 542 { 543 const unsigned int hashval = 544 (((unsigned int)((uintptr_t)ds->bdev->bd_dev)) & 545 (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1)); 546 547 list_add(&ds->collision_resolving_node, h->table + hashval); 548 } 549 550 static void btrfsic_dev_state_hashtable_remove(struct btrfsic_dev_state *ds) 551 { 552 list_del(&ds->collision_resolving_node); 553 } 554 555 static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(dev_t dev, 556 struct btrfsic_dev_state_hashtable *h) 557 { 558 const unsigned int hashval = 559 dev & (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1); 560 struct btrfsic_dev_state *ds; 561 562 list_for_each_entry(ds, h->table + hashval, collision_resolving_node) { 563 if (ds->bdev->bd_dev == dev) 564 return ds; 565 } 566 567 return NULL; 568 } 569 570 static int btrfsic_process_superblock(struct btrfsic_state *state, 571 struct btrfs_fs_devices *fs_devices) 572 { 573 struct btrfs_super_block *selected_super; 574 struct list_head *dev_head = &fs_devices->devices; 575 struct btrfs_device *device; 576 struct btrfsic_dev_state *selected_dev_state = NULL; 577 int ret = 0; 578 int pass; 579 580 selected_super = kzalloc(sizeof(*selected_super), GFP_NOFS); 581 if (!selected_super) 582 return -ENOMEM; 583 584 list_for_each_entry(device, dev_head, dev_list) { 585 int i; 586 struct btrfsic_dev_state *dev_state; 587 588 if (!device->bdev || !device->name) 589 continue; 590 591 dev_state = btrfsic_dev_state_lookup(device->bdev->bd_dev); 592 BUG_ON(NULL == dev_state); 593 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) { 594 ret = btrfsic_process_superblock_dev_mirror( 595 state, dev_state, device, i, 596 &selected_dev_state, selected_super); 597 if (0 != ret && 0 == i) { 598 kfree(selected_super); 599 return ret; 600 } 601 } 602 } 603 604 if (NULL == state->latest_superblock) { 605 pr_info("btrfsic: no superblock found!\n"); 606 kfree(selected_super); 607 return -1; 608 } 609 610 for (pass = 0; pass < 3; pass++) { 611 int num_copies; 612 int mirror_num; 613 u64 next_bytenr; 614 615 switch (pass) { 616 case 0: 617 next_bytenr = btrfs_super_root(selected_super); 618 if (state->print_mask & 619 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 620 pr_info("root@%llu\n", next_bytenr); 621 break; 622 case 1: 623 next_bytenr = btrfs_super_chunk_root(selected_super); 624 if (state->print_mask & 625 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 626 pr_info("chunk@%llu\n", next_bytenr); 627 break; 628 case 2: 629 next_bytenr = btrfs_super_log_root(selected_super); 630 if (0 == next_bytenr) 631 continue; 632 if (state->print_mask & 633 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 634 pr_info("log@%llu\n", next_bytenr); 635 break; 636 } 637 638 num_copies = btrfs_num_copies(state->fs_info, next_bytenr, 639 state->metablock_size); 640 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 641 pr_info("num_copies(log_bytenr=%llu) = %d\n", 642 next_bytenr, num_copies); 643 644 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 645 struct btrfsic_block *next_block; 646 struct btrfsic_block_data_ctx tmp_next_block_ctx; 647 struct btrfsic_block_link *l; 648 649 ret = btrfsic_map_block(state, next_bytenr, 650 state->metablock_size, 651 &tmp_next_block_ctx, 652 mirror_num); 653 if (ret) { 654 pr_info("btrfsic: btrfsic_map_block(root @%llu, mirror %d) failed!\n", 655 next_bytenr, mirror_num); 656 kfree(selected_super); 657 return -1; 658 } 659 660 next_block = btrfsic_block_hashtable_lookup( 661 tmp_next_block_ctx.dev->bdev, 662 tmp_next_block_ctx.dev_bytenr, 663 &state->block_hashtable); 664 BUG_ON(NULL == next_block); 665 666 l = btrfsic_block_link_hashtable_lookup( 667 tmp_next_block_ctx.dev->bdev, 668 tmp_next_block_ctx.dev_bytenr, 669 state->latest_superblock->dev_state-> 670 bdev, 671 state->latest_superblock->dev_bytenr, 672 &state->block_link_hashtable); 673 BUG_ON(NULL == l); 674 675 ret = btrfsic_read_block(state, &tmp_next_block_ctx); 676 if (ret < (int)PAGE_SIZE) { 677 pr_info("btrfsic: read @logical %llu failed!\n", 678 tmp_next_block_ctx.start); 679 btrfsic_release_block_ctx(&tmp_next_block_ctx); 680 kfree(selected_super); 681 return -1; 682 } 683 684 ret = btrfsic_process_metablock(state, 685 next_block, 686 &tmp_next_block_ctx, 687 BTRFS_MAX_LEVEL + 3, 1); 688 btrfsic_release_block_ctx(&tmp_next_block_ctx); 689 } 690 } 691 692 kfree(selected_super); 693 return ret; 694 } 695 696 static int btrfsic_process_superblock_dev_mirror( 697 struct btrfsic_state *state, 698 struct btrfsic_dev_state *dev_state, 699 struct btrfs_device *device, 700 int superblock_mirror_num, 701 struct btrfsic_dev_state **selected_dev_state, 702 struct btrfs_super_block *selected_super) 703 { 704 struct btrfs_fs_info *fs_info = state->fs_info; 705 struct btrfs_super_block *super_tmp; 706 u64 dev_bytenr; 707 struct btrfsic_block *superblock_tmp; 708 int pass; 709 struct block_device *const superblock_bdev = device->bdev; 710 struct page *page; 711 struct address_space *mapping = superblock_bdev->bd_inode->i_mapping; 712 int ret = 0; 713 714 /* super block bytenr is always the unmapped device bytenr */ 715 dev_bytenr = btrfs_sb_offset(superblock_mirror_num); 716 if (dev_bytenr + BTRFS_SUPER_INFO_SIZE > device->commit_total_bytes) 717 return -1; 718 719 page = read_cache_page_gfp(mapping, dev_bytenr >> PAGE_SHIFT, GFP_NOFS); 720 if (IS_ERR(page)) 721 return -1; 722 723 super_tmp = page_address(page); 724 725 if (btrfs_super_bytenr(super_tmp) != dev_bytenr || 726 btrfs_super_magic(super_tmp) != BTRFS_MAGIC || 727 memcmp(device->uuid, super_tmp->dev_item.uuid, BTRFS_UUID_SIZE) || 728 btrfs_super_nodesize(super_tmp) != state->metablock_size || 729 btrfs_super_sectorsize(super_tmp) != state->datablock_size) { 730 ret = 0; 731 goto out; 732 } 733 734 superblock_tmp = 735 btrfsic_block_hashtable_lookup(superblock_bdev, 736 dev_bytenr, 737 &state->block_hashtable); 738 if (NULL == superblock_tmp) { 739 superblock_tmp = btrfsic_block_alloc(); 740 if (NULL == superblock_tmp) { 741 ret = -1; 742 goto out; 743 } 744 /* for superblock, only the dev_bytenr makes sense */ 745 superblock_tmp->dev_bytenr = dev_bytenr; 746 superblock_tmp->dev_state = dev_state; 747 superblock_tmp->logical_bytenr = dev_bytenr; 748 superblock_tmp->generation = btrfs_super_generation(super_tmp); 749 superblock_tmp->is_metadata = 1; 750 superblock_tmp->is_superblock = 1; 751 superblock_tmp->is_iodone = 1; 752 superblock_tmp->never_written = 0; 753 superblock_tmp->mirror_num = 1 + superblock_mirror_num; 754 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE) 755 btrfs_info_in_rcu(fs_info, 756 "new initial S-block (bdev %p, %s) @%llu (%pg/%llu/%d)", 757 superblock_bdev, 758 rcu_str_deref(device->name), dev_bytenr, 759 dev_state->bdev, dev_bytenr, 760 superblock_mirror_num); 761 list_add(&superblock_tmp->all_blocks_node, 762 &state->all_blocks_list); 763 btrfsic_block_hashtable_add(superblock_tmp, 764 &state->block_hashtable); 765 } 766 767 /* select the one with the highest generation field */ 768 if (btrfs_super_generation(super_tmp) > 769 state->max_superblock_generation || 770 0 == state->max_superblock_generation) { 771 memcpy(selected_super, super_tmp, sizeof(*selected_super)); 772 *selected_dev_state = dev_state; 773 state->max_superblock_generation = 774 btrfs_super_generation(super_tmp); 775 state->latest_superblock = superblock_tmp; 776 } 777 778 for (pass = 0; pass < 3; pass++) { 779 u64 next_bytenr; 780 int num_copies; 781 int mirror_num; 782 const char *additional_string = NULL; 783 struct btrfs_disk_key tmp_disk_key; 784 785 tmp_disk_key.type = BTRFS_ROOT_ITEM_KEY; 786 tmp_disk_key.offset = 0; 787 switch (pass) { 788 case 0: 789 btrfs_set_disk_key_objectid(&tmp_disk_key, 790 BTRFS_ROOT_TREE_OBJECTID); 791 additional_string = "initial root "; 792 next_bytenr = btrfs_super_root(super_tmp); 793 break; 794 case 1: 795 btrfs_set_disk_key_objectid(&tmp_disk_key, 796 BTRFS_CHUNK_TREE_OBJECTID); 797 additional_string = "initial chunk "; 798 next_bytenr = btrfs_super_chunk_root(super_tmp); 799 break; 800 case 2: 801 btrfs_set_disk_key_objectid(&tmp_disk_key, 802 BTRFS_TREE_LOG_OBJECTID); 803 additional_string = "initial log "; 804 next_bytenr = btrfs_super_log_root(super_tmp); 805 if (0 == next_bytenr) 806 continue; 807 break; 808 } 809 810 num_copies = btrfs_num_copies(fs_info, next_bytenr, 811 state->metablock_size); 812 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 813 pr_info("num_copies(log_bytenr=%llu) = %d\n", 814 next_bytenr, num_copies); 815 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 816 struct btrfsic_block *next_block; 817 struct btrfsic_block_data_ctx tmp_next_block_ctx; 818 struct btrfsic_block_link *l; 819 820 if (btrfsic_map_block(state, next_bytenr, 821 state->metablock_size, 822 &tmp_next_block_ctx, 823 mirror_num)) { 824 pr_info("btrfsic: btrfsic_map_block(bytenr @%llu, mirror %d) failed!\n", 825 next_bytenr, mirror_num); 826 ret = -1; 827 goto out; 828 } 829 830 next_block = btrfsic_block_lookup_or_add( 831 state, &tmp_next_block_ctx, 832 additional_string, 1, 1, 0, 833 mirror_num, NULL); 834 if (NULL == next_block) { 835 btrfsic_release_block_ctx(&tmp_next_block_ctx); 836 ret = -1; 837 goto out; 838 } 839 840 next_block->disk_key = tmp_disk_key; 841 next_block->generation = BTRFSIC_GENERATION_UNKNOWN; 842 l = btrfsic_block_link_lookup_or_add( 843 state, &tmp_next_block_ctx, 844 next_block, superblock_tmp, 845 BTRFSIC_GENERATION_UNKNOWN); 846 btrfsic_release_block_ctx(&tmp_next_block_ctx); 847 if (NULL == l) { 848 ret = -1; 849 goto out; 850 } 851 } 852 } 853 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_ALL_TREES) 854 btrfsic_dump_tree_sub(state, superblock_tmp, 0); 855 856 out: 857 put_page(page); 858 return ret; 859 } 860 861 static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void) 862 { 863 struct btrfsic_stack_frame *sf; 864 865 sf = kzalloc(sizeof(*sf), GFP_NOFS); 866 if (sf) 867 sf->magic = BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER; 868 return sf; 869 } 870 871 static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf) 872 { 873 BUG_ON(!(NULL == sf || 874 BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER == sf->magic)); 875 kfree(sf); 876 } 877 878 static noinline_for_stack int btrfsic_process_metablock( 879 struct btrfsic_state *state, 880 struct btrfsic_block *const first_block, 881 struct btrfsic_block_data_ctx *const first_block_ctx, 882 int first_limit_nesting, int force_iodone_flag) 883 { 884 struct btrfsic_stack_frame initial_stack_frame = { 0 }; 885 struct btrfsic_stack_frame *sf; 886 struct btrfsic_stack_frame *next_stack; 887 struct btrfs_header *const first_hdr = 888 (struct btrfs_header *)first_block_ctx->datav[0]; 889 890 BUG_ON(!first_hdr); 891 sf = &initial_stack_frame; 892 sf->error = 0; 893 sf->i = -1; 894 sf->limit_nesting = first_limit_nesting; 895 sf->block = first_block; 896 sf->block_ctx = first_block_ctx; 897 sf->next_block = NULL; 898 sf->hdr = first_hdr; 899 sf->prev = NULL; 900 901 continue_with_new_stack_frame: 902 sf->block->generation = btrfs_stack_header_generation(sf->hdr); 903 if (0 == sf->hdr->level) { 904 struct btrfs_leaf *const leafhdr = 905 (struct btrfs_leaf *)sf->hdr; 906 907 if (-1 == sf->i) { 908 sf->nr = btrfs_stack_header_nritems(&leafhdr->header); 909 910 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 911 pr_info("leaf %llu items %d generation %llu owner %llu\n", 912 sf->block_ctx->start, sf->nr, 913 btrfs_stack_header_generation( 914 &leafhdr->header), 915 btrfs_stack_header_owner( 916 &leafhdr->header)); 917 } 918 919 continue_with_current_leaf_stack_frame: 920 if (0 == sf->num_copies || sf->mirror_num > sf->num_copies) { 921 sf->i++; 922 sf->num_copies = 0; 923 } 924 925 if (sf->i < sf->nr) { 926 struct btrfs_item disk_item; 927 u32 disk_item_offset = 928 (uintptr_t)(leafhdr->items + sf->i) - 929 (uintptr_t)leafhdr; 930 struct btrfs_disk_key *disk_key; 931 u8 type; 932 u32 item_offset; 933 u32 item_size; 934 935 if (disk_item_offset + sizeof(struct btrfs_item) > 936 sf->block_ctx->len) { 937 leaf_item_out_of_bounce_error: 938 pr_info( 939 "btrfsic: leaf item out of bounce at logical %llu, dev %pg\n", 940 sf->block_ctx->start, 941 sf->block_ctx->dev->bdev); 942 goto one_stack_frame_backwards; 943 } 944 btrfsic_read_from_block_data(sf->block_ctx, 945 &disk_item, 946 disk_item_offset, 947 sizeof(struct btrfs_item)); 948 item_offset = btrfs_stack_item_offset(&disk_item); 949 item_size = btrfs_stack_item_size(&disk_item); 950 disk_key = &disk_item.key; 951 type = btrfs_disk_key_type(disk_key); 952 953 if (BTRFS_ROOT_ITEM_KEY == type) { 954 struct btrfs_root_item root_item; 955 u32 root_item_offset; 956 u64 next_bytenr; 957 958 root_item_offset = item_offset + 959 offsetof(struct btrfs_leaf, items); 960 if (root_item_offset + item_size > 961 sf->block_ctx->len) 962 goto leaf_item_out_of_bounce_error; 963 btrfsic_read_from_block_data( 964 sf->block_ctx, &root_item, 965 root_item_offset, 966 item_size); 967 next_bytenr = btrfs_root_bytenr(&root_item); 968 969 sf->error = 970 btrfsic_create_link_to_next_block( 971 state, 972 sf->block, 973 sf->block_ctx, 974 next_bytenr, 975 sf->limit_nesting, 976 &sf->next_block_ctx, 977 &sf->next_block, 978 force_iodone_flag, 979 &sf->num_copies, 980 &sf->mirror_num, 981 disk_key, 982 btrfs_root_generation( 983 &root_item)); 984 if (sf->error) 985 goto one_stack_frame_backwards; 986 987 if (NULL != sf->next_block) { 988 struct btrfs_header *const next_hdr = 989 (struct btrfs_header *) 990 sf->next_block_ctx.datav[0]; 991 992 next_stack = 993 btrfsic_stack_frame_alloc(); 994 if (NULL == next_stack) { 995 sf->error = -1; 996 btrfsic_release_block_ctx( 997 &sf-> 998 next_block_ctx); 999 goto one_stack_frame_backwards; 1000 } 1001 1002 next_stack->i = -1; 1003 next_stack->block = sf->next_block; 1004 next_stack->block_ctx = 1005 &sf->next_block_ctx; 1006 next_stack->next_block = NULL; 1007 next_stack->hdr = next_hdr; 1008 next_stack->limit_nesting = 1009 sf->limit_nesting - 1; 1010 next_stack->prev = sf; 1011 sf = next_stack; 1012 goto continue_with_new_stack_frame; 1013 } 1014 } else if (BTRFS_EXTENT_DATA_KEY == type && 1015 state->include_extent_data) { 1016 sf->error = btrfsic_handle_extent_data( 1017 state, 1018 sf->block, 1019 sf->block_ctx, 1020 item_offset, 1021 force_iodone_flag); 1022 if (sf->error) 1023 goto one_stack_frame_backwards; 1024 } 1025 1026 goto continue_with_current_leaf_stack_frame; 1027 } 1028 } else { 1029 struct btrfs_node *const nodehdr = (struct btrfs_node *)sf->hdr; 1030 1031 if (-1 == sf->i) { 1032 sf->nr = btrfs_stack_header_nritems(&nodehdr->header); 1033 1034 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1035 pr_info("node %llu level %d items %d generation %llu owner %llu\n", 1036 sf->block_ctx->start, 1037 nodehdr->header.level, sf->nr, 1038 btrfs_stack_header_generation( 1039 &nodehdr->header), 1040 btrfs_stack_header_owner( 1041 &nodehdr->header)); 1042 } 1043 1044 continue_with_current_node_stack_frame: 1045 if (0 == sf->num_copies || sf->mirror_num > sf->num_copies) { 1046 sf->i++; 1047 sf->num_copies = 0; 1048 } 1049 1050 if (sf->i < sf->nr) { 1051 struct btrfs_key_ptr key_ptr; 1052 u32 key_ptr_offset; 1053 u64 next_bytenr; 1054 1055 key_ptr_offset = (uintptr_t)(nodehdr->ptrs + sf->i) - 1056 (uintptr_t)nodehdr; 1057 if (key_ptr_offset + sizeof(struct btrfs_key_ptr) > 1058 sf->block_ctx->len) { 1059 pr_info( 1060 "btrfsic: node item out of bounce at logical %llu, dev %pg\n", 1061 sf->block_ctx->start, 1062 sf->block_ctx->dev->bdev); 1063 goto one_stack_frame_backwards; 1064 } 1065 btrfsic_read_from_block_data( 1066 sf->block_ctx, &key_ptr, key_ptr_offset, 1067 sizeof(struct btrfs_key_ptr)); 1068 next_bytenr = btrfs_stack_key_blockptr(&key_ptr); 1069 1070 sf->error = btrfsic_create_link_to_next_block( 1071 state, 1072 sf->block, 1073 sf->block_ctx, 1074 next_bytenr, 1075 sf->limit_nesting, 1076 &sf->next_block_ctx, 1077 &sf->next_block, 1078 force_iodone_flag, 1079 &sf->num_copies, 1080 &sf->mirror_num, 1081 &key_ptr.key, 1082 btrfs_stack_key_generation(&key_ptr)); 1083 if (sf->error) 1084 goto one_stack_frame_backwards; 1085 1086 if (NULL != sf->next_block) { 1087 struct btrfs_header *const next_hdr = 1088 (struct btrfs_header *) 1089 sf->next_block_ctx.datav[0]; 1090 1091 next_stack = btrfsic_stack_frame_alloc(); 1092 if (NULL == next_stack) { 1093 sf->error = -1; 1094 goto one_stack_frame_backwards; 1095 } 1096 1097 next_stack->i = -1; 1098 next_stack->block = sf->next_block; 1099 next_stack->block_ctx = &sf->next_block_ctx; 1100 next_stack->next_block = NULL; 1101 next_stack->hdr = next_hdr; 1102 next_stack->limit_nesting = 1103 sf->limit_nesting - 1; 1104 next_stack->prev = sf; 1105 sf = next_stack; 1106 goto continue_with_new_stack_frame; 1107 } 1108 1109 goto continue_with_current_node_stack_frame; 1110 } 1111 } 1112 1113 one_stack_frame_backwards: 1114 if (NULL != sf->prev) { 1115 struct btrfsic_stack_frame *const prev = sf->prev; 1116 1117 /* the one for the initial block is freed in the caller */ 1118 btrfsic_release_block_ctx(sf->block_ctx); 1119 1120 if (sf->error) { 1121 prev->error = sf->error; 1122 btrfsic_stack_frame_free(sf); 1123 sf = prev; 1124 goto one_stack_frame_backwards; 1125 } 1126 1127 btrfsic_stack_frame_free(sf); 1128 sf = prev; 1129 goto continue_with_new_stack_frame; 1130 } else { 1131 BUG_ON(&initial_stack_frame != sf); 1132 } 1133 1134 return sf->error; 1135 } 1136 1137 static void btrfsic_read_from_block_data( 1138 struct btrfsic_block_data_ctx *block_ctx, 1139 void *dstv, u32 offset, size_t len) 1140 { 1141 size_t cur; 1142 size_t pgoff; 1143 char *kaddr; 1144 char *dst = (char *)dstv; 1145 size_t start_offset = offset_in_page(block_ctx->start); 1146 unsigned long i = (start_offset + offset) >> PAGE_SHIFT; 1147 1148 WARN_ON(offset + len > block_ctx->len); 1149 pgoff = offset_in_page(start_offset + offset); 1150 1151 while (len > 0) { 1152 cur = min(len, ((size_t)PAGE_SIZE - pgoff)); 1153 BUG_ON(i >= DIV_ROUND_UP(block_ctx->len, PAGE_SIZE)); 1154 kaddr = block_ctx->datav[i]; 1155 memcpy(dst, kaddr + pgoff, cur); 1156 1157 dst += cur; 1158 len -= cur; 1159 pgoff = 0; 1160 i++; 1161 } 1162 } 1163 1164 static int btrfsic_create_link_to_next_block( 1165 struct btrfsic_state *state, 1166 struct btrfsic_block *block, 1167 struct btrfsic_block_data_ctx *block_ctx, 1168 u64 next_bytenr, 1169 int limit_nesting, 1170 struct btrfsic_block_data_ctx *next_block_ctx, 1171 struct btrfsic_block **next_blockp, 1172 int force_iodone_flag, 1173 int *num_copiesp, int *mirror_nump, 1174 struct btrfs_disk_key *disk_key, 1175 u64 parent_generation) 1176 { 1177 struct btrfs_fs_info *fs_info = state->fs_info; 1178 struct btrfsic_block *next_block = NULL; 1179 int ret; 1180 struct btrfsic_block_link *l; 1181 int did_alloc_block_link; 1182 int block_was_created; 1183 1184 *next_blockp = NULL; 1185 if (0 == *num_copiesp) { 1186 *num_copiesp = btrfs_num_copies(fs_info, next_bytenr, 1187 state->metablock_size); 1188 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 1189 pr_info("num_copies(log_bytenr=%llu) = %d\n", 1190 next_bytenr, *num_copiesp); 1191 *mirror_nump = 1; 1192 } 1193 1194 if (*mirror_nump > *num_copiesp) 1195 return 0; 1196 1197 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1198 pr_info("btrfsic_create_link_to_next_block(mirror_num=%d)\n", 1199 *mirror_nump); 1200 ret = btrfsic_map_block(state, next_bytenr, 1201 state->metablock_size, 1202 next_block_ctx, *mirror_nump); 1203 if (ret) { 1204 pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n", 1205 next_bytenr, *mirror_nump); 1206 btrfsic_release_block_ctx(next_block_ctx); 1207 *next_blockp = NULL; 1208 return -1; 1209 } 1210 1211 next_block = btrfsic_block_lookup_or_add(state, 1212 next_block_ctx, "referenced ", 1213 1, force_iodone_flag, 1214 !force_iodone_flag, 1215 *mirror_nump, 1216 &block_was_created); 1217 if (NULL == next_block) { 1218 btrfsic_release_block_ctx(next_block_ctx); 1219 *next_blockp = NULL; 1220 return -1; 1221 } 1222 if (block_was_created) { 1223 l = NULL; 1224 next_block->generation = BTRFSIC_GENERATION_UNKNOWN; 1225 } else { 1226 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) { 1227 if (next_block->logical_bytenr != next_bytenr && 1228 !(!next_block->is_metadata && 1229 0 == next_block->logical_bytenr)) 1230 pr_info( 1231 "referenced block @%llu (%pg/%llu/%d) found in hash table, %c, bytenr mismatch (!= stored %llu)\n", 1232 next_bytenr, next_block_ctx->dev->bdev, 1233 next_block_ctx->dev_bytenr, *mirror_nump, 1234 btrfsic_get_block_type(state, 1235 next_block), 1236 next_block->logical_bytenr); 1237 else 1238 pr_info( 1239 "referenced block @%llu (%pg/%llu/%d) found in hash table, %c\n", 1240 next_bytenr, next_block_ctx->dev->bdev, 1241 next_block_ctx->dev_bytenr, *mirror_nump, 1242 btrfsic_get_block_type(state, 1243 next_block)); 1244 } 1245 next_block->logical_bytenr = next_bytenr; 1246 1247 next_block->mirror_num = *mirror_nump; 1248 l = btrfsic_block_link_hashtable_lookup( 1249 next_block_ctx->dev->bdev, 1250 next_block_ctx->dev_bytenr, 1251 block_ctx->dev->bdev, 1252 block_ctx->dev_bytenr, 1253 &state->block_link_hashtable); 1254 } 1255 1256 next_block->disk_key = *disk_key; 1257 if (NULL == l) { 1258 l = btrfsic_block_link_alloc(); 1259 if (NULL == l) { 1260 btrfsic_release_block_ctx(next_block_ctx); 1261 *next_blockp = NULL; 1262 return -1; 1263 } 1264 1265 did_alloc_block_link = 1; 1266 l->block_ref_to = next_block; 1267 l->block_ref_from = block; 1268 l->ref_cnt = 1; 1269 l->parent_generation = parent_generation; 1270 1271 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1272 btrfsic_print_add_link(state, l); 1273 1274 list_add(&l->node_ref_to, &block->ref_to_list); 1275 list_add(&l->node_ref_from, &next_block->ref_from_list); 1276 1277 btrfsic_block_link_hashtable_add(l, 1278 &state->block_link_hashtable); 1279 } else { 1280 did_alloc_block_link = 0; 1281 if (0 == limit_nesting) { 1282 l->ref_cnt++; 1283 l->parent_generation = parent_generation; 1284 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1285 btrfsic_print_add_link(state, l); 1286 } 1287 } 1288 1289 if (limit_nesting > 0 && did_alloc_block_link) { 1290 ret = btrfsic_read_block(state, next_block_ctx); 1291 if (ret < (int)next_block_ctx->len) { 1292 pr_info("btrfsic: read block @logical %llu failed!\n", 1293 next_bytenr); 1294 btrfsic_release_block_ctx(next_block_ctx); 1295 *next_blockp = NULL; 1296 return -1; 1297 } 1298 1299 *next_blockp = next_block; 1300 } else { 1301 *next_blockp = NULL; 1302 } 1303 (*mirror_nump)++; 1304 1305 return 0; 1306 } 1307 1308 static int btrfsic_handle_extent_data( 1309 struct btrfsic_state *state, 1310 struct btrfsic_block *block, 1311 struct btrfsic_block_data_ctx *block_ctx, 1312 u32 item_offset, int force_iodone_flag) 1313 { 1314 struct btrfs_fs_info *fs_info = state->fs_info; 1315 struct btrfs_file_extent_item file_extent_item; 1316 u64 file_extent_item_offset; 1317 u64 next_bytenr; 1318 u64 num_bytes; 1319 u64 generation; 1320 struct btrfsic_block_link *l; 1321 int ret; 1322 1323 file_extent_item_offset = offsetof(struct btrfs_leaf, items) + 1324 item_offset; 1325 if (file_extent_item_offset + 1326 offsetof(struct btrfs_file_extent_item, disk_num_bytes) > 1327 block_ctx->len) { 1328 pr_info("btrfsic: file item out of bounce at logical %llu, dev %pg\n", 1329 block_ctx->start, block_ctx->dev->bdev); 1330 return -1; 1331 } 1332 1333 btrfsic_read_from_block_data(block_ctx, &file_extent_item, 1334 file_extent_item_offset, 1335 offsetof(struct btrfs_file_extent_item, disk_num_bytes)); 1336 if (BTRFS_FILE_EXTENT_REG != file_extent_item.type || 1337 btrfs_stack_file_extent_disk_bytenr(&file_extent_item) == 0) { 1338 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE) 1339 pr_info("extent_data: type %u, disk_bytenr = %llu\n", 1340 file_extent_item.type, 1341 btrfs_stack_file_extent_disk_bytenr( 1342 &file_extent_item)); 1343 return 0; 1344 } 1345 1346 if (file_extent_item_offset + sizeof(struct btrfs_file_extent_item) > 1347 block_ctx->len) { 1348 pr_info("btrfsic: file item out of bounce at logical %llu, dev %pg\n", 1349 block_ctx->start, block_ctx->dev->bdev); 1350 return -1; 1351 } 1352 btrfsic_read_from_block_data(block_ctx, &file_extent_item, 1353 file_extent_item_offset, 1354 sizeof(struct btrfs_file_extent_item)); 1355 next_bytenr = btrfs_stack_file_extent_disk_bytenr(&file_extent_item); 1356 if (btrfs_stack_file_extent_compression(&file_extent_item) == 1357 BTRFS_COMPRESS_NONE) { 1358 next_bytenr += btrfs_stack_file_extent_offset(&file_extent_item); 1359 num_bytes = btrfs_stack_file_extent_num_bytes(&file_extent_item); 1360 } else { 1361 num_bytes = btrfs_stack_file_extent_disk_num_bytes(&file_extent_item); 1362 } 1363 generation = btrfs_stack_file_extent_generation(&file_extent_item); 1364 1365 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE) 1366 pr_info("extent_data: type %u, disk_bytenr = %llu, offset = %llu, num_bytes = %llu\n", 1367 file_extent_item.type, 1368 btrfs_stack_file_extent_disk_bytenr(&file_extent_item), 1369 btrfs_stack_file_extent_offset(&file_extent_item), 1370 num_bytes); 1371 while (num_bytes > 0) { 1372 u32 chunk_len; 1373 int num_copies; 1374 int mirror_num; 1375 1376 if (num_bytes > state->datablock_size) 1377 chunk_len = state->datablock_size; 1378 else 1379 chunk_len = num_bytes; 1380 1381 num_copies = btrfs_num_copies(fs_info, next_bytenr, 1382 state->datablock_size); 1383 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 1384 pr_info("num_copies(log_bytenr=%llu) = %d\n", 1385 next_bytenr, num_copies); 1386 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 1387 struct btrfsic_block_data_ctx next_block_ctx; 1388 struct btrfsic_block *next_block; 1389 int block_was_created; 1390 1391 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1392 pr_info("btrfsic_handle_extent_data(mirror_num=%d)\n", 1393 mirror_num); 1394 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE) 1395 pr_info("\tdisk_bytenr = %llu, num_bytes %u\n", 1396 next_bytenr, chunk_len); 1397 ret = btrfsic_map_block(state, next_bytenr, 1398 chunk_len, &next_block_ctx, 1399 mirror_num); 1400 if (ret) { 1401 pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n", 1402 next_bytenr, mirror_num); 1403 return -1; 1404 } 1405 1406 next_block = btrfsic_block_lookup_or_add( 1407 state, 1408 &next_block_ctx, 1409 "referenced ", 1410 0, 1411 force_iodone_flag, 1412 !force_iodone_flag, 1413 mirror_num, 1414 &block_was_created); 1415 if (NULL == next_block) { 1416 btrfsic_release_block_ctx(&next_block_ctx); 1417 return -1; 1418 } 1419 if (!block_was_created) { 1420 if ((state->print_mask & 1421 BTRFSIC_PRINT_MASK_VERBOSE) && 1422 next_block->logical_bytenr != next_bytenr && 1423 !(!next_block->is_metadata && 1424 0 == next_block->logical_bytenr)) { 1425 pr_info( 1426 "referenced block @%llu (%pg/%llu/%d) found in hash table, D, bytenr mismatch (!= stored %llu)\n", 1427 next_bytenr, 1428 next_block_ctx.dev->bdev, 1429 next_block_ctx.dev_bytenr, 1430 mirror_num, 1431 next_block->logical_bytenr); 1432 } 1433 next_block->logical_bytenr = next_bytenr; 1434 next_block->mirror_num = mirror_num; 1435 } 1436 1437 l = btrfsic_block_link_lookup_or_add(state, 1438 &next_block_ctx, 1439 next_block, block, 1440 generation); 1441 btrfsic_release_block_ctx(&next_block_ctx); 1442 if (NULL == l) 1443 return -1; 1444 } 1445 1446 next_bytenr += chunk_len; 1447 num_bytes -= chunk_len; 1448 } 1449 1450 return 0; 1451 } 1452 1453 static int btrfsic_map_block(struct btrfsic_state *state, u64 bytenr, u32 len, 1454 struct btrfsic_block_data_ctx *block_ctx_out, 1455 int mirror_num) 1456 { 1457 struct btrfs_fs_info *fs_info = state->fs_info; 1458 int ret; 1459 u64 length; 1460 struct btrfs_io_context *multi = NULL; 1461 struct btrfs_device *device; 1462 1463 length = len; 1464 ret = btrfs_map_block(fs_info, BTRFS_MAP_READ, 1465 bytenr, &length, &multi, mirror_num); 1466 1467 if (ret) { 1468 block_ctx_out->start = 0; 1469 block_ctx_out->dev_bytenr = 0; 1470 block_ctx_out->len = 0; 1471 block_ctx_out->dev = NULL; 1472 block_ctx_out->datav = NULL; 1473 block_ctx_out->pagev = NULL; 1474 block_ctx_out->mem_to_free = NULL; 1475 1476 return ret; 1477 } 1478 1479 device = multi->stripes[0].dev; 1480 if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state) || 1481 !device->bdev || !device->name) 1482 block_ctx_out->dev = NULL; 1483 else 1484 block_ctx_out->dev = btrfsic_dev_state_lookup( 1485 device->bdev->bd_dev); 1486 block_ctx_out->dev_bytenr = multi->stripes[0].physical; 1487 block_ctx_out->start = bytenr; 1488 block_ctx_out->len = len; 1489 block_ctx_out->datav = NULL; 1490 block_ctx_out->pagev = NULL; 1491 block_ctx_out->mem_to_free = NULL; 1492 1493 kfree(multi); 1494 if (NULL == block_ctx_out->dev) { 1495 ret = -ENXIO; 1496 pr_info("btrfsic: error, cannot lookup dev (#1)!\n"); 1497 } 1498 1499 return ret; 1500 } 1501 1502 static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx) 1503 { 1504 if (block_ctx->mem_to_free) { 1505 unsigned int num_pages; 1506 1507 BUG_ON(!block_ctx->datav); 1508 BUG_ON(!block_ctx->pagev); 1509 num_pages = (block_ctx->len + (u64)PAGE_SIZE - 1) >> 1510 PAGE_SHIFT; 1511 /* Pages must be unmapped in reverse order */ 1512 while (num_pages > 0) { 1513 num_pages--; 1514 if (block_ctx->datav[num_pages]) 1515 block_ctx->datav[num_pages] = NULL; 1516 if (block_ctx->pagev[num_pages]) { 1517 __free_page(block_ctx->pagev[num_pages]); 1518 block_ctx->pagev[num_pages] = NULL; 1519 } 1520 } 1521 1522 kfree(block_ctx->mem_to_free); 1523 block_ctx->mem_to_free = NULL; 1524 block_ctx->pagev = NULL; 1525 block_ctx->datav = NULL; 1526 } 1527 } 1528 1529 static int btrfsic_read_block(struct btrfsic_state *state, 1530 struct btrfsic_block_data_ctx *block_ctx) 1531 { 1532 unsigned int num_pages; 1533 unsigned int i; 1534 size_t size; 1535 u64 dev_bytenr; 1536 int ret; 1537 1538 BUG_ON(block_ctx->datav); 1539 BUG_ON(block_ctx->pagev); 1540 BUG_ON(block_ctx->mem_to_free); 1541 if (!PAGE_ALIGNED(block_ctx->dev_bytenr)) { 1542 pr_info("btrfsic: read_block() with unaligned bytenr %llu\n", 1543 block_ctx->dev_bytenr); 1544 return -1; 1545 } 1546 1547 num_pages = (block_ctx->len + (u64)PAGE_SIZE - 1) >> 1548 PAGE_SHIFT; 1549 size = sizeof(*block_ctx->datav) + sizeof(*block_ctx->pagev); 1550 block_ctx->mem_to_free = kcalloc(num_pages, size, GFP_NOFS); 1551 if (!block_ctx->mem_to_free) 1552 return -ENOMEM; 1553 block_ctx->datav = block_ctx->mem_to_free; 1554 block_ctx->pagev = (struct page **)(block_ctx->datav + num_pages); 1555 for (i = 0; i < num_pages; i++) { 1556 block_ctx->pagev[i] = alloc_page(GFP_NOFS); 1557 if (!block_ctx->pagev[i]) 1558 return -1; 1559 } 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 = btrfs_bio_alloc(num_pages - i); 1567 bio_set_dev(bio, block_ctx->dev->bdev); 1568 bio->bi_iter.bi_sector = dev_bytenr >> 9; 1569 bio->bi_opf = REQ_OP_READ; 1570 1571 for (j = i; j < num_pages; j++) { 1572 ret = bio_add_page(bio, block_ctx->pagev[j], 1573 PAGE_SIZE, 0); 1574 if (PAGE_SIZE != ret) 1575 break; 1576 } 1577 if (j == i) { 1578 pr_info("btrfsic: error, failed to add a single page!\n"); 1579 return -1; 1580 } 1581 if (submit_bio_wait(bio)) { 1582 pr_info("btrfsic: read error at logical %llu dev %pg!\n", 1583 block_ctx->start, block_ctx->dev->bdev); 1584 bio_put(bio); 1585 return -1; 1586 } 1587 bio_put(bio); 1588 dev_bytenr += (j - i) * PAGE_SIZE; 1589 i = j; 1590 } 1591 for (i = 0; i < num_pages; i++) 1592 block_ctx->datav[i] = page_address(block_ctx->pagev[i]); 1593 1594 return block_ctx->len; 1595 } 1596 1597 static void btrfsic_dump_database(struct btrfsic_state *state) 1598 { 1599 const struct btrfsic_block *b_all; 1600 1601 BUG_ON(NULL == state); 1602 1603 pr_info("all_blocks_list:\n"); 1604 list_for_each_entry(b_all, &state->all_blocks_list, all_blocks_node) { 1605 const struct btrfsic_block_link *l; 1606 1607 pr_info("%c-block @%llu (%pg/%llu/%d)\n", 1608 btrfsic_get_block_type(state, b_all), 1609 b_all->logical_bytenr, b_all->dev_state->bdev, 1610 b_all->dev_bytenr, b_all->mirror_num); 1611 1612 list_for_each_entry(l, &b_all->ref_to_list, node_ref_to) { 1613 pr_info( 1614 " %c @%llu (%pg/%llu/%d) refers %u* to %c @%llu (%pg/%llu/%d)\n", 1615 btrfsic_get_block_type(state, b_all), 1616 b_all->logical_bytenr, b_all->dev_state->bdev, 1617 b_all->dev_bytenr, b_all->mirror_num, 1618 l->ref_cnt, 1619 btrfsic_get_block_type(state, l->block_ref_to), 1620 l->block_ref_to->logical_bytenr, 1621 l->block_ref_to->dev_state->bdev, 1622 l->block_ref_to->dev_bytenr, 1623 l->block_ref_to->mirror_num); 1624 } 1625 1626 list_for_each_entry(l, &b_all->ref_from_list, node_ref_from) { 1627 pr_info( 1628 " %c @%llu (%pg/%llu/%d) is ref %u* from %c @%llu (%pg/%llu/%d)\n", 1629 btrfsic_get_block_type(state, b_all), 1630 b_all->logical_bytenr, b_all->dev_state->bdev, 1631 b_all->dev_bytenr, b_all->mirror_num, 1632 l->ref_cnt, 1633 btrfsic_get_block_type(state, l->block_ref_from), 1634 l->block_ref_from->logical_bytenr, 1635 l->block_ref_from->dev_state->bdev, 1636 l->block_ref_from->dev_bytenr, 1637 l->block_ref_from->mirror_num); 1638 } 1639 1640 pr_info("\n"); 1641 } 1642 } 1643 1644 /* 1645 * Test whether the disk block contains a tree block (leaf or node) 1646 * (note that this test fails for the super block) 1647 */ 1648 static noinline_for_stack int btrfsic_test_for_metadata( 1649 struct btrfsic_state *state, 1650 char **datav, unsigned int num_pages) 1651 { 1652 struct btrfs_fs_info *fs_info = state->fs_info; 1653 SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); 1654 struct btrfs_header *h; 1655 u8 csum[BTRFS_CSUM_SIZE]; 1656 unsigned int i; 1657 1658 if (num_pages * PAGE_SIZE < state->metablock_size) 1659 return 1; /* not metadata */ 1660 num_pages = state->metablock_size >> PAGE_SHIFT; 1661 h = (struct btrfs_header *)datav[0]; 1662 1663 if (memcmp(h->fsid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE)) 1664 return 1; 1665 1666 shash->tfm = fs_info->csum_shash; 1667 crypto_shash_init(shash); 1668 1669 for (i = 0; i < num_pages; i++) { 1670 u8 *data = i ? datav[i] : (datav[i] + BTRFS_CSUM_SIZE); 1671 size_t sublen = i ? PAGE_SIZE : 1672 (PAGE_SIZE - BTRFS_CSUM_SIZE); 1673 1674 crypto_shash_update(shash, data, sublen); 1675 } 1676 crypto_shash_final(shash, csum); 1677 if (memcmp(csum, h->csum, fs_info->csum_size)) 1678 return 1; 1679 1680 return 0; /* is metadata */ 1681 } 1682 1683 static void btrfsic_process_written_block(struct btrfsic_dev_state *dev_state, 1684 u64 dev_bytenr, char **mapped_datav, 1685 unsigned int num_pages, 1686 struct bio *bio, int *bio_is_patched, 1687 int submit_bio_bh_rw) 1688 { 1689 int is_metadata; 1690 struct btrfsic_block *block; 1691 struct btrfsic_block_data_ctx block_ctx; 1692 int ret; 1693 struct btrfsic_state *state = dev_state->state; 1694 struct block_device *bdev = dev_state->bdev; 1695 unsigned int processed_len; 1696 1697 if (NULL != bio_is_patched) 1698 *bio_is_patched = 0; 1699 1700 again: 1701 if (num_pages == 0) 1702 return; 1703 1704 processed_len = 0; 1705 is_metadata = (0 == btrfsic_test_for_metadata(state, mapped_datav, 1706 num_pages)); 1707 1708 block = btrfsic_block_hashtable_lookup(bdev, dev_bytenr, 1709 &state->block_hashtable); 1710 if (NULL != block) { 1711 u64 bytenr = 0; 1712 struct btrfsic_block_link *l, *tmp; 1713 1714 if (block->is_superblock) { 1715 bytenr = btrfs_super_bytenr((struct btrfs_super_block *) 1716 mapped_datav[0]); 1717 if (num_pages * PAGE_SIZE < 1718 BTRFS_SUPER_INFO_SIZE) { 1719 pr_info("btrfsic: cannot work with too short bios!\n"); 1720 return; 1721 } 1722 is_metadata = 1; 1723 BUG_ON(!PAGE_ALIGNED(BTRFS_SUPER_INFO_SIZE)); 1724 processed_len = BTRFS_SUPER_INFO_SIZE; 1725 if (state->print_mask & 1726 BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE) { 1727 pr_info("[before new superblock is written]:\n"); 1728 btrfsic_dump_tree_sub(state, block, 0); 1729 } 1730 } 1731 if (is_metadata) { 1732 if (!block->is_superblock) { 1733 if (num_pages * PAGE_SIZE < 1734 state->metablock_size) { 1735 pr_info("btrfsic: cannot work with too short bios!\n"); 1736 return; 1737 } 1738 processed_len = state->metablock_size; 1739 bytenr = btrfs_stack_header_bytenr( 1740 (struct btrfs_header *) 1741 mapped_datav[0]); 1742 btrfsic_cmp_log_and_dev_bytenr(state, bytenr, 1743 dev_state, 1744 dev_bytenr); 1745 } 1746 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) { 1747 if (block->logical_bytenr != bytenr && 1748 !(!block->is_metadata && 1749 block->logical_bytenr == 0)) 1750 pr_info( 1751 "written block @%llu (%pg/%llu/%d) found in hash table, %c, bytenr mismatch (!= stored %llu)\n", 1752 bytenr, dev_state->bdev, 1753 dev_bytenr, 1754 block->mirror_num, 1755 btrfsic_get_block_type(state, 1756 block), 1757 block->logical_bytenr); 1758 else 1759 pr_info( 1760 "written block @%llu (%pg/%llu/%d) found in hash table, %c\n", 1761 bytenr, dev_state->bdev, 1762 dev_bytenr, block->mirror_num, 1763 btrfsic_get_block_type(state, 1764 block)); 1765 } 1766 block->logical_bytenr = bytenr; 1767 } else { 1768 if (num_pages * PAGE_SIZE < 1769 state->datablock_size) { 1770 pr_info("btrfsic: cannot work with too short bios!\n"); 1771 return; 1772 } 1773 processed_len = state->datablock_size; 1774 bytenr = block->logical_bytenr; 1775 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1776 pr_info( 1777 "written block @%llu (%pg/%llu/%d) found in hash table, %c\n", 1778 bytenr, dev_state->bdev, dev_bytenr, 1779 block->mirror_num, 1780 btrfsic_get_block_type(state, block)); 1781 } 1782 1783 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1784 pr_info("ref_to_list: %cE, ref_from_list: %cE\n", 1785 list_empty(&block->ref_to_list) ? ' ' : '!', 1786 list_empty(&block->ref_from_list) ? ' ' : '!'); 1787 if (btrfsic_is_block_ref_by_superblock(state, block, 0)) { 1788 pr_info( 1789 "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", 1790 btrfsic_get_block_type(state, block), bytenr, 1791 dev_state->bdev, dev_bytenr, block->mirror_num, 1792 block->generation, 1793 btrfs_disk_key_objectid(&block->disk_key), 1794 block->disk_key.type, 1795 btrfs_disk_key_offset(&block->disk_key), 1796 btrfs_stack_header_generation( 1797 (struct btrfs_header *) mapped_datav[0]), 1798 state->max_superblock_generation); 1799 btrfsic_dump_tree(state); 1800 } 1801 1802 if (!block->is_iodone && !block->never_written) { 1803 pr_info( 1804 "btrfs: attempt to overwrite %c-block @%llu (%pg/%llu/%d), oldgen=%llu, newgen=%llu, which is not yet iodone!\n", 1805 btrfsic_get_block_type(state, block), bytenr, 1806 dev_state->bdev, dev_bytenr, block->mirror_num, 1807 block->generation, 1808 btrfs_stack_header_generation( 1809 (struct btrfs_header *) 1810 mapped_datav[0])); 1811 /* it would not be safe to go on */ 1812 btrfsic_dump_tree(state); 1813 goto continue_loop; 1814 } 1815 1816 /* 1817 * Clear all references of this block. Do not free 1818 * the block itself even if is not referenced anymore 1819 * because it still carries valuable information 1820 * like whether it was ever written and IO completed. 1821 */ 1822 list_for_each_entry_safe(l, tmp, &block->ref_to_list, 1823 node_ref_to) { 1824 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1825 btrfsic_print_rem_link(state, l); 1826 l->ref_cnt--; 1827 if (0 == l->ref_cnt) { 1828 list_del(&l->node_ref_to); 1829 list_del(&l->node_ref_from); 1830 btrfsic_block_link_hashtable_remove(l); 1831 btrfsic_block_link_free(l); 1832 } 1833 } 1834 1835 block_ctx.dev = dev_state; 1836 block_ctx.dev_bytenr = dev_bytenr; 1837 block_ctx.start = bytenr; 1838 block_ctx.len = processed_len; 1839 block_ctx.pagev = NULL; 1840 block_ctx.mem_to_free = NULL; 1841 block_ctx.datav = mapped_datav; 1842 1843 if (is_metadata || state->include_extent_data) { 1844 block->never_written = 0; 1845 block->iodone_w_error = 0; 1846 if (NULL != bio) { 1847 block->is_iodone = 0; 1848 BUG_ON(NULL == bio_is_patched); 1849 if (!*bio_is_patched) { 1850 block->orig_bio_private = 1851 bio->bi_private; 1852 block->orig_bio_end_io = 1853 bio->bi_end_io; 1854 block->next_in_same_bio = NULL; 1855 bio->bi_private = block; 1856 bio->bi_end_io = btrfsic_bio_end_io; 1857 *bio_is_patched = 1; 1858 } else { 1859 struct btrfsic_block *chained_block = 1860 (struct btrfsic_block *) 1861 bio->bi_private; 1862 1863 BUG_ON(NULL == chained_block); 1864 block->orig_bio_private = 1865 chained_block->orig_bio_private; 1866 block->orig_bio_end_io = 1867 chained_block->orig_bio_end_io; 1868 block->next_in_same_bio = chained_block; 1869 bio->bi_private = block; 1870 } 1871 } else { 1872 block->is_iodone = 1; 1873 block->orig_bio_private = NULL; 1874 block->orig_bio_end_io = NULL; 1875 block->next_in_same_bio = NULL; 1876 } 1877 } 1878 1879 block->flush_gen = dev_state->last_flush_gen + 1; 1880 block->submit_bio_bh_rw = submit_bio_bh_rw; 1881 if (is_metadata) { 1882 block->logical_bytenr = bytenr; 1883 block->is_metadata = 1; 1884 if (block->is_superblock) { 1885 BUG_ON(PAGE_SIZE != 1886 BTRFS_SUPER_INFO_SIZE); 1887 ret = btrfsic_process_written_superblock( 1888 state, 1889 block, 1890 (struct btrfs_super_block *) 1891 mapped_datav[0]); 1892 if (state->print_mask & 1893 BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE) { 1894 pr_info("[after new superblock is written]:\n"); 1895 btrfsic_dump_tree_sub(state, block, 0); 1896 } 1897 } else { 1898 block->mirror_num = 0; /* unknown */ 1899 ret = btrfsic_process_metablock( 1900 state, 1901 block, 1902 &block_ctx, 1903 0, 0); 1904 } 1905 if (ret) 1906 pr_info("btrfsic: btrfsic_process_metablock(root @%llu) failed!\n", 1907 dev_bytenr); 1908 } else { 1909 block->is_metadata = 0; 1910 block->mirror_num = 0; /* unknown */ 1911 block->generation = BTRFSIC_GENERATION_UNKNOWN; 1912 if (!state->include_extent_data 1913 && list_empty(&block->ref_from_list)) { 1914 /* 1915 * disk block is overwritten with extent 1916 * data (not meta data) and we are configured 1917 * to not include extent data: take the 1918 * chance and free the block's memory 1919 */ 1920 btrfsic_block_hashtable_remove(block); 1921 list_del(&block->all_blocks_node); 1922 btrfsic_block_free(block); 1923 } 1924 } 1925 btrfsic_release_block_ctx(&block_ctx); 1926 } else { 1927 /* block has not been found in hash table */ 1928 u64 bytenr; 1929 1930 if (!is_metadata) { 1931 processed_len = state->datablock_size; 1932 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1933 pr_info( 1934 "written block (%pg/%llu/?) !found in hash table, D\n", 1935 dev_state->bdev, dev_bytenr); 1936 if (!state->include_extent_data) { 1937 /* ignore that written D block */ 1938 goto continue_loop; 1939 } 1940 1941 /* this is getting ugly for the 1942 * include_extent_data case... */ 1943 bytenr = 0; /* unknown */ 1944 } else { 1945 processed_len = state->metablock_size; 1946 bytenr = btrfs_stack_header_bytenr( 1947 (struct btrfs_header *) 1948 mapped_datav[0]); 1949 btrfsic_cmp_log_and_dev_bytenr(state, bytenr, dev_state, 1950 dev_bytenr); 1951 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1952 pr_info( 1953 "written block @%llu (%pg/%llu/?) !found in hash table, M\n", 1954 bytenr, dev_state->bdev, dev_bytenr); 1955 } 1956 1957 block_ctx.dev = dev_state; 1958 block_ctx.dev_bytenr = dev_bytenr; 1959 block_ctx.start = bytenr; 1960 block_ctx.len = processed_len; 1961 block_ctx.pagev = NULL; 1962 block_ctx.mem_to_free = NULL; 1963 block_ctx.datav = mapped_datav; 1964 1965 block = btrfsic_block_alloc(); 1966 if (NULL == block) { 1967 btrfsic_release_block_ctx(&block_ctx); 1968 goto continue_loop; 1969 } 1970 block->dev_state = dev_state; 1971 block->dev_bytenr = dev_bytenr; 1972 block->logical_bytenr = bytenr; 1973 block->is_metadata = is_metadata; 1974 block->never_written = 0; 1975 block->iodone_w_error = 0; 1976 block->mirror_num = 0; /* unknown */ 1977 block->flush_gen = dev_state->last_flush_gen + 1; 1978 block->submit_bio_bh_rw = submit_bio_bh_rw; 1979 if (NULL != bio) { 1980 block->is_iodone = 0; 1981 BUG_ON(NULL == bio_is_patched); 1982 if (!*bio_is_patched) { 1983 block->orig_bio_private = bio->bi_private; 1984 block->orig_bio_end_io = bio->bi_end_io; 1985 block->next_in_same_bio = NULL; 1986 bio->bi_private = block; 1987 bio->bi_end_io = btrfsic_bio_end_io; 1988 *bio_is_patched = 1; 1989 } else { 1990 struct btrfsic_block *chained_block = 1991 (struct btrfsic_block *) 1992 bio->bi_private; 1993 1994 BUG_ON(NULL == chained_block); 1995 block->orig_bio_private = 1996 chained_block->orig_bio_private; 1997 block->orig_bio_end_io = 1998 chained_block->orig_bio_end_io; 1999 block->next_in_same_bio = chained_block; 2000 bio->bi_private = block; 2001 } 2002 } else { 2003 block->is_iodone = 1; 2004 block->orig_bio_private = NULL; 2005 block->orig_bio_end_io = NULL; 2006 block->next_in_same_bio = NULL; 2007 } 2008 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2009 pr_info("new written %c-block @%llu (%pg/%llu/%d)\n", 2010 is_metadata ? 'M' : 'D', 2011 block->logical_bytenr, block->dev_state->bdev, 2012 block->dev_bytenr, block->mirror_num); 2013 list_add(&block->all_blocks_node, &state->all_blocks_list); 2014 btrfsic_block_hashtable_add(block, &state->block_hashtable); 2015 2016 if (is_metadata) { 2017 ret = btrfsic_process_metablock(state, block, 2018 &block_ctx, 0, 0); 2019 if (ret) 2020 pr_info("btrfsic: process_metablock(root @%llu) failed!\n", 2021 dev_bytenr); 2022 } 2023 btrfsic_release_block_ctx(&block_ctx); 2024 } 2025 2026 continue_loop: 2027 BUG_ON(!processed_len); 2028 dev_bytenr += processed_len; 2029 mapped_datav += processed_len >> PAGE_SHIFT; 2030 num_pages -= processed_len >> PAGE_SHIFT; 2031 goto again; 2032 } 2033 2034 static void btrfsic_bio_end_io(struct bio *bp) 2035 { 2036 struct btrfsic_block *block = (struct btrfsic_block *)bp->bi_private; 2037 int iodone_w_error; 2038 2039 /* mutex is not held! This is not save if IO is not yet completed 2040 * on umount */ 2041 iodone_w_error = 0; 2042 if (bp->bi_status) 2043 iodone_w_error = 1; 2044 2045 BUG_ON(NULL == block); 2046 bp->bi_private = block->orig_bio_private; 2047 bp->bi_end_io = block->orig_bio_end_io; 2048 2049 do { 2050 struct btrfsic_block *next_block; 2051 struct btrfsic_dev_state *const dev_state = block->dev_state; 2052 2053 if ((dev_state->state->print_mask & 2054 BTRFSIC_PRINT_MASK_END_IO_BIO_BH)) 2055 pr_info("bio_end_io(err=%d) for %c @%llu (%pg/%llu/%d)\n", 2056 bp->bi_status, 2057 btrfsic_get_block_type(dev_state->state, block), 2058 block->logical_bytenr, dev_state->bdev, 2059 block->dev_bytenr, block->mirror_num); 2060 next_block = block->next_in_same_bio; 2061 block->iodone_w_error = iodone_w_error; 2062 if (block->submit_bio_bh_rw & REQ_PREFLUSH) { 2063 dev_state->last_flush_gen++; 2064 if ((dev_state->state->print_mask & 2065 BTRFSIC_PRINT_MASK_END_IO_BIO_BH)) 2066 pr_info("bio_end_io() new %pg flush_gen=%llu\n", 2067 dev_state->bdev, 2068 dev_state->last_flush_gen); 2069 } 2070 if (block->submit_bio_bh_rw & REQ_FUA) 2071 block->flush_gen = 0; /* FUA completed means block is 2072 * on disk */ 2073 block->is_iodone = 1; /* for FLUSH, this releases the block */ 2074 block = next_block; 2075 } while (NULL != block); 2076 2077 bp->bi_end_io(bp); 2078 } 2079 2080 static int btrfsic_process_written_superblock( 2081 struct btrfsic_state *state, 2082 struct btrfsic_block *const superblock, 2083 struct btrfs_super_block *const super_hdr) 2084 { 2085 struct btrfs_fs_info *fs_info = state->fs_info; 2086 int pass; 2087 2088 superblock->generation = btrfs_super_generation(super_hdr); 2089 if (!(superblock->generation > state->max_superblock_generation || 2090 0 == state->max_superblock_generation)) { 2091 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE) 2092 pr_info( 2093 "btrfsic: superblock @%llu (%pg/%llu/%d) with old gen %llu <= %llu\n", 2094 superblock->logical_bytenr, 2095 superblock->dev_state->bdev, 2096 superblock->dev_bytenr, superblock->mirror_num, 2097 btrfs_super_generation(super_hdr), 2098 state->max_superblock_generation); 2099 } else { 2100 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE) 2101 pr_info( 2102 "btrfsic: got new superblock @%llu (%pg/%llu/%d) with new gen %llu > %llu\n", 2103 superblock->logical_bytenr, 2104 superblock->dev_state->bdev, 2105 superblock->dev_bytenr, superblock->mirror_num, 2106 btrfs_super_generation(super_hdr), 2107 state->max_superblock_generation); 2108 2109 state->max_superblock_generation = 2110 btrfs_super_generation(super_hdr); 2111 state->latest_superblock = superblock; 2112 } 2113 2114 for (pass = 0; pass < 3; pass++) { 2115 int ret; 2116 u64 next_bytenr; 2117 struct btrfsic_block *next_block; 2118 struct btrfsic_block_data_ctx tmp_next_block_ctx; 2119 struct btrfsic_block_link *l; 2120 int num_copies; 2121 int mirror_num; 2122 const char *additional_string = NULL; 2123 struct btrfs_disk_key tmp_disk_key = {0}; 2124 2125 btrfs_set_disk_key_objectid(&tmp_disk_key, 2126 BTRFS_ROOT_ITEM_KEY); 2127 btrfs_set_disk_key_objectid(&tmp_disk_key, 0); 2128 2129 switch (pass) { 2130 case 0: 2131 btrfs_set_disk_key_objectid(&tmp_disk_key, 2132 BTRFS_ROOT_TREE_OBJECTID); 2133 additional_string = "root "; 2134 next_bytenr = btrfs_super_root(super_hdr); 2135 if (state->print_mask & 2136 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 2137 pr_info("root@%llu\n", next_bytenr); 2138 break; 2139 case 1: 2140 btrfs_set_disk_key_objectid(&tmp_disk_key, 2141 BTRFS_CHUNK_TREE_OBJECTID); 2142 additional_string = "chunk "; 2143 next_bytenr = btrfs_super_chunk_root(super_hdr); 2144 if (state->print_mask & 2145 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 2146 pr_info("chunk@%llu\n", next_bytenr); 2147 break; 2148 case 2: 2149 btrfs_set_disk_key_objectid(&tmp_disk_key, 2150 BTRFS_TREE_LOG_OBJECTID); 2151 additional_string = "log "; 2152 next_bytenr = btrfs_super_log_root(super_hdr); 2153 if (0 == next_bytenr) 2154 continue; 2155 if (state->print_mask & 2156 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 2157 pr_info("log@%llu\n", next_bytenr); 2158 break; 2159 } 2160 2161 num_copies = btrfs_num_copies(fs_info, next_bytenr, 2162 BTRFS_SUPER_INFO_SIZE); 2163 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 2164 pr_info("num_copies(log_bytenr=%llu) = %d\n", 2165 next_bytenr, num_copies); 2166 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 2167 int was_created; 2168 2169 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2170 pr_info("btrfsic_process_written_superblock(mirror_num=%d)\n", mirror_num); 2171 ret = btrfsic_map_block(state, next_bytenr, 2172 BTRFS_SUPER_INFO_SIZE, 2173 &tmp_next_block_ctx, 2174 mirror_num); 2175 if (ret) { 2176 pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n", 2177 next_bytenr, mirror_num); 2178 return -1; 2179 } 2180 2181 next_block = btrfsic_block_lookup_or_add( 2182 state, 2183 &tmp_next_block_ctx, 2184 additional_string, 2185 1, 0, 1, 2186 mirror_num, 2187 &was_created); 2188 if (NULL == next_block) { 2189 btrfsic_release_block_ctx(&tmp_next_block_ctx); 2190 return -1; 2191 } 2192 2193 next_block->disk_key = tmp_disk_key; 2194 if (was_created) 2195 next_block->generation = 2196 BTRFSIC_GENERATION_UNKNOWN; 2197 l = btrfsic_block_link_lookup_or_add( 2198 state, 2199 &tmp_next_block_ctx, 2200 next_block, 2201 superblock, 2202 BTRFSIC_GENERATION_UNKNOWN); 2203 btrfsic_release_block_ctx(&tmp_next_block_ctx); 2204 if (NULL == l) 2205 return -1; 2206 } 2207 } 2208 2209 if (WARN_ON(-1 == btrfsic_check_all_ref_blocks(state, superblock, 0))) 2210 btrfsic_dump_tree(state); 2211 2212 return 0; 2213 } 2214 2215 static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state, 2216 struct btrfsic_block *const block, 2217 int recursion_level) 2218 { 2219 const struct btrfsic_block_link *l; 2220 int ret = 0; 2221 2222 if (recursion_level >= 3 + BTRFS_MAX_LEVEL) { 2223 /* 2224 * Note that this situation can happen and does not 2225 * indicate an error in regular cases. It happens 2226 * when disk blocks are freed and later reused. 2227 * The check-integrity module is not aware of any 2228 * block free operations, it just recognizes block 2229 * write operations. Therefore it keeps the linkage 2230 * information for a block until a block is 2231 * rewritten. This can temporarily cause incorrect 2232 * and even circular linkage information. This 2233 * causes no harm unless such blocks are referenced 2234 * by the most recent super block. 2235 */ 2236 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2237 pr_info("btrfsic: abort cyclic linkage (case 1).\n"); 2238 2239 return ret; 2240 } 2241 2242 /* 2243 * This algorithm is recursive because the amount of used stack 2244 * space is very small and the max recursion depth is limited. 2245 */ 2246 list_for_each_entry(l, &block->ref_to_list, node_ref_to) { 2247 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2248 pr_info( 2249 "rl=%d, %c @%llu (%pg/%llu/%d) %u* refers to %c @%llu (%pg/%llu/%d)\n", 2250 recursion_level, 2251 btrfsic_get_block_type(state, block), 2252 block->logical_bytenr, block->dev_state->bdev, 2253 block->dev_bytenr, block->mirror_num, 2254 l->ref_cnt, 2255 btrfsic_get_block_type(state, l->block_ref_to), 2256 l->block_ref_to->logical_bytenr, 2257 l->block_ref_to->dev_state->bdev, 2258 l->block_ref_to->dev_bytenr, 2259 l->block_ref_to->mirror_num); 2260 if (l->block_ref_to->never_written) { 2261 pr_info( 2262 "btrfs: attempt to write superblock which references block %c @%llu (%pg/%llu/%d) which is never written!\n", 2263 btrfsic_get_block_type(state, l->block_ref_to), 2264 l->block_ref_to->logical_bytenr, 2265 l->block_ref_to->dev_state->bdev, 2266 l->block_ref_to->dev_bytenr, 2267 l->block_ref_to->mirror_num); 2268 ret = -1; 2269 } else if (!l->block_ref_to->is_iodone) { 2270 pr_info( 2271 "btrfs: attempt to write superblock which references block %c @%llu (%pg/%llu/%d) which is not yet iodone!\n", 2272 btrfsic_get_block_type(state, l->block_ref_to), 2273 l->block_ref_to->logical_bytenr, 2274 l->block_ref_to->dev_state->bdev, 2275 l->block_ref_to->dev_bytenr, 2276 l->block_ref_to->mirror_num); 2277 ret = -1; 2278 } else if (l->block_ref_to->iodone_w_error) { 2279 pr_info( 2280 "btrfs: attempt to write superblock which references block %c @%llu (%pg/%llu/%d) which has write error!\n", 2281 btrfsic_get_block_type(state, l->block_ref_to), 2282 l->block_ref_to->logical_bytenr, 2283 l->block_ref_to->dev_state->bdev, 2284 l->block_ref_to->dev_bytenr, 2285 l->block_ref_to->mirror_num); 2286 ret = -1; 2287 } else if (l->parent_generation != 2288 l->block_ref_to->generation && 2289 BTRFSIC_GENERATION_UNKNOWN != 2290 l->parent_generation && 2291 BTRFSIC_GENERATION_UNKNOWN != 2292 l->block_ref_to->generation) { 2293 pr_info( 2294 "btrfs: attempt to write superblock which references block %c @%llu (%pg/%llu/%d) with generation %llu != parent generation %llu!\n", 2295 btrfsic_get_block_type(state, l->block_ref_to), 2296 l->block_ref_to->logical_bytenr, 2297 l->block_ref_to->dev_state->bdev, 2298 l->block_ref_to->dev_bytenr, 2299 l->block_ref_to->mirror_num, 2300 l->block_ref_to->generation, 2301 l->parent_generation); 2302 ret = -1; 2303 } else if (l->block_ref_to->flush_gen > 2304 l->block_ref_to->dev_state->last_flush_gen) { 2305 pr_info( 2306 "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", 2307 btrfsic_get_block_type(state, l->block_ref_to), 2308 l->block_ref_to->logical_bytenr, 2309 l->block_ref_to->dev_state->bdev, 2310 l->block_ref_to->dev_bytenr, 2311 l->block_ref_to->mirror_num, block->flush_gen, 2312 l->block_ref_to->dev_state->last_flush_gen); 2313 ret = -1; 2314 } else if (-1 == btrfsic_check_all_ref_blocks(state, 2315 l->block_ref_to, 2316 recursion_level + 2317 1)) { 2318 ret = -1; 2319 } 2320 } 2321 2322 return ret; 2323 } 2324 2325 static int btrfsic_is_block_ref_by_superblock( 2326 const struct btrfsic_state *state, 2327 const struct btrfsic_block *block, 2328 int recursion_level) 2329 { 2330 const struct btrfsic_block_link *l; 2331 2332 if (recursion_level >= 3 + BTRFS_MAX_LEVEL) { 2333 /* refer to comment at "abort cyclic linkage (case 1)" */ 2334 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2335 pr_info("btrfsic: abort cyclic linkage (case 2).\n"); 2336 2337 return 0; 2338 } 2339 2340 /* 2341 * This algorithm is recursive because the amount of used stack space 2342 * is very small and the max recursion depth is limited. 2343 */ 2344 list_for_each_entry(l, &block->ref_from_list, node_ref_from) { 2345 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2346 pr_info( 2347 "rl=%d, %c @%llu (%pg/%llu/%d) is ref %u* from %c @%llu (%pg/%llu/%d)\n", 2348 recursion_level, 2349 btrfsic_get_block_type(state, block), 2350 block->logical_bytenr, block->dev_state->bdev, 2351 block->dev_bytenr, block->mirror_num, 2352 l->ref_cnt, 2353 btrfsic_get_block_type(state, l->block_ref_from), 2354 l->block_ref_from->logical_bytenr, 2355 l->block_ref_from->dev_state->bdev, 2356 l->block_ref_from->dev_bytenr, 2357 l->block_ref_from->mirror_num); 2358 if (l->block_ref_from->is_superblock && 2359 state->latest_superblock->dev_bytenr == 2360 l->block_ref_from->dev_bytenr && 2361 state->latest_superblock->dev_state->bdev == 2362 l->block_ref_from->dev_state->bdev) 2363 return 1; 2364 else if (btrfsic_is_block_ref_by_superblock(state, 2365 l->block_ref_from, 2366 recursion_level + 2367 1)) 2368 return 1; 2369 } 2370 2371 return 0; 2372 } 2373 2374 static void btrfsic_print_add_link(const struct btrfsic_state *state, 2375 const struct btrfsic_block_link *l) 2376 { 2377 pr_info("add %u* link from %c @%llu (%pg/%llu/%d) to %c @%llu (%pg/%llu/%d)\n", 2378 l->ref_cnt, 2379 btrfsic_get_block_type(state, l->block_ref_from), 2380 l->block_ref_from->logical_bytenr, 2381 l->block_ref_from->dev_state->bdev, 2382 l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num, 2383 btrfsic_get_block_type(state, l->block_ref_to), 2384 l->block_ref_to->logical_bytenr, 2385 l->block_ref_to->dev_state->bdev, l->block_ref_to->dev_bytenr, 2386 l->block_ref_to->mirror_num); 2387 } 2388 2389 static void btrfsic_print_rem_link(const struct btrfsic_state *state, 2390 const struct btrfsic_block_link *l) 2391 { 2392 pr_info("rem %u* link from %c @%llu (%pg/%llu/%d) to %c @%llu (%pg/%llu/%d)\n", 2393 l->ref_cnt, 2394 btrfsic_get_block_type(state, l->block_ref_from), 2395 l->block_ref_from->logical_bytenr, 2396 l->block_ref_from->dev_state->bdev, 2397 l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num, 2398 btrfsic_get_block_type(state, l->block_ref_to), 2399 l->block_ref_to->logical_bytenr, 2400 l->block_ref_to->dev_state->bdev, l->block_ref_to->dev_bytenr, 2401 l->block_ref_to->mirror_num); 2402 } 2403 2404 static char btrfsic_get_block_type(const struct btrfsic_state *state, 2405 const struct btrfsic_block *block) 2406 { 2407 if (block->is_superblock && 2408 state->latest_superblock->dev_bytenr == block->dev_bytenr && 2409 state->latest_superblock->dev_state->bdev == block->dev_state->bdev) 2410 return 'S'; 2411 else if (block->is_superblock) 2412 return 's'; 2413 else if (block->is_metadata) 2414 return 'M'; 2415 else 2416 return 'D'; 2417 } 2418 2419 static void btrfsic_dump_tree(const struct btrfsic_state *state) 2420 { 2421 btrfsic_dump_tree_sub(state, state->latest_superblock, 0); 2422 } 2423 2424 static void btrfsic_dump_tree_sub(const struct btrfsic_state *state, 2425 const struct btrfsic_block *block, 2426 int indent_level) 2427 { 2428 const struct btrfsic_block_link *l; 2429 int indent_add; 2430 static char buf[80]; 2431 int cursor_position; 2432 2433 /* 2434 * Should better fill an on-stack buffer with a complete line and 2435 * dump it at once when it is time to print a newline character. 2436 */ 2437 2438 /* 2439 * This algorithm is recursive because the amount of used stack space 2440 * is very small and the max recursion depth is limited. 2441 */ 2442 indent_add = sprintf(buf, "%c-%llu(%pg/%llu/%u)", 2443 btrfsic_get_block_type(state, block), 2444 block->logical_bytenr, block->dev_state->bdev, 2445 block->dev_bytenr, block->mirror_num); 2446 if (indent_level + indent_add > BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) { 2447 printk("[...]\n"); 2448 return; 2449 } 2450 printk(buf); 2451 indent_level += indent_add; 2452 if (list_empty(&block->ref_to_list)) { 2453 printk("\n"); 2454 return; 2455 } 2456 if (block->mirror_num > 1 && 2457 !(state->print_mask & BTRFSIC_PRINT_MASK_TREE_WITH_ALL_MIRRORS)) { 2458 printk(" [...]\n"); 2459 return; 2460 } 2461 2462 cursor_position = indent_level; 2463 list_for_each_entry(l, &block->ref_to_list, node_ref_to) { 2464 while (cursor_position < indent_level) { 2465 printk(" "); 2466 cursor_position++; 2467 } 2468 if (l->ref_cnt > 1) 2469 indent_add = sprintf(buf, " %d*--> ", l->ref_cnt); 2470 else 2471 indent_add = sprintf(buf, " --> "); 2472 if (indent_level + indent_add > 2473 BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) { 2474 printk("[...]\n"); 2475 cursor_position = 0; 2476 continue; 2477 } 2478 2479 printk(buf); 2480 2481 btrfsic_dump_tree_sub(state, l->block_ref_to, 2482 indent_level + indent_add); 2483 cursor_position = 0; 2484 } 2485 } 2486 2487 static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add( 2488 struct btrfsic_state *state, 2489 struct btrfsic_block_data_ctx *next_block_ctx, 2490 struct btrfsic_block *next_block, 2491 struct btrfsic_block *from_block, 2492 u64 parent_generation) 2493 { 2494 struct btrfsic_block_link *l; 2495 2496 l = btrfsic_block_link_hashtable_lookup(next_block_ctx->dev->bdev, 2497 next_block_ctx->dev_bytenr, 2498 from_block->dev_state->bdev, 2499 from_block->dev_bytenr, 2500 &state->block_link_hashtable); 2501 if (NULL == l) { 2502 l = btrfsic_block_link_alloc(); 2503 if (!l) 2504 return NULL; 2505 2506 l->block_ref_to = next_block; 2507 l->block_ref_from = from_block; 2508 l->ref_cnt = 1; 2509 l->parent_generation = parent_generation; 2510 2511 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2512 btrfsic_print_add_link(state, l); 2513 2514 list_add(&l->node_ref_to, &from_block->ref_to_list); 2515 list_add(&l->node_ref_from, &next_block->ref_from_list); 2516 2517 btrfsic_block_link_hashtable_add(l, 2518 &state->block_link_hashtable); 2519 } else { 2520 l->ref_cnt++; 2521 l->parent_generation = parent_generation; 2522 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2523 btrfsic_print_add_link(state, l); 2524 } 2525 2526 return l; 2527 } 2528 2529 static struct btrfsic_block *btrfsic_block_lookup_or_add( 2530 struct btrfsic_state *state, 2531 struct btrfsic_block_data_ctx *block_ctx, 2532 const char *additional_string, 2533 int is_metadata, 2534 int is_iodone, 2535 int never_written, 2536 int mirror_num, 2537 int *was_created) 2538 { 2539 struct btrfsic_block *block; 2540 2541 block = btrfsic_block_hashtable_lookup(block_ctx->dev->bdev, 2542 block_ctx->dev_bytenr, 2543 &state->block_hashtable); 2544 if (NULL == block) { 2545 struct btrfsic_dev_state *dev_state; 2546 2547 block = btrfsic_block_alloc(); 2548 if (!block) 2549 return NULL; 2550 2551 dev_state = btrfsic_dev_state_lookup(block_ctx->dev->bdev->bd_dev); 2552 if (NULL == dev_state) { 2553 pr_info("btrfsic: error, lookup dev_state failed!\n"); 2554 btrfsic_block_free(block); 2555 return NULL; 2556 } 2557 block->dev_state = dev_state; 2558 block->dev_bytenr = block_ctx->dev_bytenr; 2559 block->logical_bytenr = block_ctx->start; 2560 block->is_metadata = is_metadata; 2561 block->is_iodone = is_iodone; 2562 block->never_written = never_written; 2563 block->mirror_num = mirror_num; 2564 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2565 pr_info("New %s%c-block @%llu (%pg/%llu/%d)\n", 2566 additional_string, 2567 btrfsic_get_block_type(state, block), 2568 block->logical_bytenr, dev_state->bdev, 2569 block->dev_bytenr, mirror_num); 2570 list_add(&block->all_blocks_node, &state->all_blocks_list); 2571 btrfsic_block_hashtable_add(block, &state->block_hashtable); 2572 if (NULL != was_created) 2573 *was_created = 1; 2574 } else { 2575 if (NULL != was_created) 2576 *was_created = 0; 2577 } 2578 2579 return block; 2580 } 2581 2582 static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state, 2583 u64 bytenr, 2584 struct btrfsic_dev_state *dev_state, 2585 u64 dev_bytenr) 2586 { 2587 struct btrfs_fs_info *fs_info = state->fs_info; 2588 struct btrfsic_block_data_ctx block_ctx; 2589 int num_copies; 2590 int mirror_num; 2591 int match = 0; 2592 int ret; 2593 2594 num_copies = btrfs_num_copies(fs_info, bytenr, state->metablock_size); 2595 2596 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 2597 ret = btrfsic_map_block(state, bytenr, state->metablock_size, 2598 &block_ctx, mirror_num); 2599 if (ret) { 2600 pr_info("btrfsic: btrfsic_map_block(logical @%llu, mirror %d) failed!\n", 2601 bytenr, mirror_num); 2602 continue; 2603 } 2604 2605 if (dev_state->bdev == block_ctx.dev->bdev && 2606 dev_bytenr == block_ctx.dev_bytenr) { 2607 match++; 2608 btrfsic_release_block_ctx(&block_ctx); 2609 break; 2610 } 2611 btrfsic_release_block_ctx(&block_ctx); 2612 } 2613 2614 if (WARN_ON(!match)) { 2615 pr_info( 2616 "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", 2617 bytenr, dev_state->bdev, dev_bytenr); 2618 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 2619 ret = btrfsic_map_block(state, bytenr, 2620 state->metablock_size, 2621 &block_ctx, mirror_num); 2622 if (ret) 2623 continue; 2624 2625 pr_info("read logical bytenr @%llu maps to (%pg/%llu/%d)\n", 2626 bytenr, block_ctx.dev->bdev, 2627 block_ctx.dev_bytenr, mirror_num); 2628 } 2629 } 2630 } 2631 2632 static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev) 2633 { 2634 return btrfsic_dev_state_hashtable_lookup(dev, 2635 &btrfsic_dev_state_hashtable); 2636 } 2637 2638 static void __btrfsic_submit_bio(struct bio *bio) 2639 { 2640 struct btrfsic_dev_state *dev_state; 2641 2642 if (!btrfsic_is_initialized) 2643 return; 2644 2645 mutex_lock(&btrfsic_mutex); 2646 /* since btrfsic_submit_bio() is also called before 2647 * btrfsic_mount(), this might return NULL */ 2648 dev_state = btrfsic_dev_state_lookup(bio->bi_bdev->bd_dev); 2649 if (NULL != dev_state && 2650 (bio_op(bio) == REQ_OP_WRITE) && bio_has_data(bio)) { 2651 int i = 0; 2652 u64 dev_bytenr; 2653 u64 cur_bytenr; 2654 struct bio_vec bvec; 2655 struct bvec_iter iter; 2656 int bio_is_patched; 2657 char **mapped_datav; 2658 unsigned int segs = bio_segments(bio); 2659 2660 dev_bytenr = 512 * bio->bi_iter.bi_sector; 2661 bio_is_patched = 0; 2662 if (dev_state->state->print_mask & 2663 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH) 2664 pr_info("submit_bio(rw=%d,0x%x, bi_vcnt=%u, bi_sector=%llu (bytenr %llu), bi_bdev=%p)\n", 2665 bio_op(bio), bio->bi_opf, segs, 2666 bio->bi_iter.bi_sector, dev_bytenr, bio->bi_bdev); 2667 2668 mapped_datav = kmalloc_array(segs, 2669 sizeof(*mapped_datav), GFP_NOFS); 2670 if (!mapped_datav) 2671 goto leave; 2672 cur_bytenr = dev_bytenr; 2673 2674 bio_for_each_segment(bvec, bio, iter) { 2675 BUG_ON(bvec.bv_len != PAGE_SIZE); 2676 mapped_datav[i] = page_address(bvec.bv_page); 2677 i++; 2678 2679 if (dev_state->state->print_mask & 2680 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE) 2681 pr_info("#%u: bytenr=%llu, len=%u, offset=%u\n", 2682 i, cur_bytenr, bvec.bv_len, bvec.bv_offset); 2683 cur_bytenr += bvec.bv_len; 2684 } 2685 btrfsic_process_written_block(dev_state, dev_bytenr, 2686 mapped_datav, segs, 2687 bio, &bio_is_patched, 2688 bio->bi_opf); 2689 kfree(mapped_datav); 2690 } else if (NULL != dev_state && (bio->bi_opf & REQ_PREFLUSH)) { 2691 if (dev_state->state->print_mask & 2692 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH) 2693 pr_info("submit_bio(rw=%d,0x%x FLUSH, bdev=%p)\n", 2694 bio_op(bio), bio->bi_opf, bio->bi_bdev); 2695 if (!dev_state->dummy_block_for_bio_bh_flush.is_iodone) { 2696 if ((dev_state->state->print_mask & 2697 (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH | 2698 BTRFSIC_PRINT_MASK_VERBOSE))) 2699 pr_info( 2700 "btrfsic_submit_bio(%pg) with FLUSH but dummy block already in use (ignored)!\n", 2701 dev_state->bdev); 2702 } else { 2703 struct btrfsic_block *const block = 2704 &dev_state->dummy_block_for_bio_bh_flush; 2705 2706 block->is_iodone = 0; 2707 block->never_written = 0; 2708 block->iodone_w_error = 0; 2709 block->flush_gen = dev_state->last_flush_gen + 1; 2710 block->submit_bio_bh_rw = bio->bi_opf; 2711 block->orig_bio_private = bio->bi_private; 2712 block->orig_bio_end_io = bio->bi_end_io; 2713 block->next_in_same_bio = NULL; 2714 bio->bi_private = block; 2715 bio->bi_end_io = btrfsic_bio_end_io; 2716 } 2717 } 2718 leave: 2719 mutex_unlock(&btrfsic_mutex); 2720 } 2721 2722 void btrfsic_submit_bio(struct bio *bio) 2723 { 2724 __btrfsic_submit_bio(bio); 2725 submit_bio(bio); 2726 } 2727 2728 int btrfsic_submit_bio_wait(struct bio *bio) 2729 { 2730 __btrfsic_submit_bio(bio); 2731 return submit_bio_wait(bio); 2732 } 2733 2734 int btrfsic_mount(struct btrfs_fs_info *fs_info, 2735 struct btrfs_fs_devices *fs_devices, 2736 int including_extent_data, u32 print_mask) 2737 { 2738 int ret; 2739 struct btrfsic_state *state; 2740 struct list_head *dev_head = &fs_devices->devices; 2741 struct btrfs_device *device; 2742 2743 if (!PAGE_ALIGNED(fs_info->nodesize)) { 2744 pr_info("btrfsic: cannot handle nodesize %d not being a multiple of PAGE_SIZE %ld!\n", 2745 fs_info->nodesize, PAGE_SIZE); 2746 return -1; 2747 } 2748 if (!PAGE_ALIGNED(fs_info->sectorsize)) { 2749 pr_info("btrfsic: cannot handle sectorsize %d not being a multiple of PAGE_SIZE %ld!\n", 2750 fs_info->sectorsize, PAGE_SIZE); 2751 return -1; 2752 } 2753 state = kvzalloc(sizeof(*state), GFP_KERNEL); 2754 if (!state) 2755 return -ENOMEM; 2756 2757 if (!btrfsic_is_initialized) { 2758 mutex_init(&btrfsic_mutex); 2759 btrfsic_dev_state_hashtable_init(&btrfsic_dev_state_hashtable); 2760 btrfsic_is_initialized = 1; 2761 } 2762 mutex_lock(&btrfsic_mutex); 2763 state->fs_info = fs_info; 2764 state->print_mask = print_mask; 2765 state->include_extent_data = including_extent_data; 2766 state->metablock_size = fs_info->nodesize; 2767 state->datablock_size = fs_info->sectorsize; 2768 INIT_LIST_HEAD(&state->all_blocks_list); 2769 btrfsic_block_hashtable_init(&state->block_hashtable); 2770 btrfsic_block_link_hashtable_init(&state->block_link_hashtable); 2771 state->max_superblock_generation = 0; 2772 state->latest_superblock = NULL; 2773 2774 list_for_each_entry(device, dev_head, dev_list) { 2775 struct btrfsic_dev_state *ds; 2776 2777 if (!device->bdev || !device->name) 2778 continue; 2779 2780 ds = btrfsic_dev_state_alloc(); 2781 if (NULL == ds) { 2782 mutex_unlock(&btrfsic_mutex); 2783 return -ENOMEM; 2784 } 2785 ds->bdev = device->bdev; 2786 ds->state = state; 2787 btrfsic_dev_state_hashtable_add(ds, 2788 &btrfsic_dev_state_hashtable); 2789 } 2790 2791 ret = btrfsic_process_superblock(state, fs_devices); 2792 if (0 != ret) { 2793 mutex_unlock(&btrfsic_mutex); 2794 btrfsic_unmount(fs_devices); 2795 return ret; 2796 } 2797 2798 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_DATABASE) 2799 btrfsic_dump_database(state); 2800 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_TREE) 2801 btrfsic_dump_tree(state); 2802 2803 mutex_unlock(&btrfsic_mutex); 2804 return 0; 2805 } 2806 2807 void btrfsic_unmount(struct btrfs_fs_devices *fs_devices) 2808 { 2809 struct btrfsic_block *b_all, *tmp_all; 2810 struct btrfsic_state *state; 2811 struct list_head *dev_head = &fs_devices->devices; 2812 struct btrfs_device *device; 2813 2814 if (!btrfsic_is_initialized) 2815 return; 2816 2817 mutex_lock(&btrfsic_mutex); 2818 2819 state = NULL; 2820 list_for_each_entry(device, dev_head, dev_list) { 2821 struct btrfsic_dev_state *ds; 2822 2823 if (!device->bdev || !device->name) 2824 continue; 2825 2826 ds = btrfsic_dev_state_hashtable_lookup( 2827 device->bdev->bd_dev, 2828 &btrfsic_dev_state_hashtable); 2829 if (NULL != ds) { 2830 state = ds->state; 2831 btrfsic_dev_state_hashtable_remove(ds); 2832 btrfsic_dev_state_free(ds); 2833 } 2834 } 2835 2836 if (NULL == state) { 2837 pr_info("btrfsic: error, cannot find state information on umount!\n"); 2838 mutex_unlock(&btrfsic_mutex); 2839 return; 2840 } 2841 2842 /* 2843 * Don't care about keeping the lists' state up to date, 2844 * just free all memory that was allocated dynamically. 2845 * Free the blocks and the block_links. 2846 */ 2847 list_for_each_entry_safe(b_all, tmp_all, &state->all_blocks_list, 2848 all_blocks_node) { 2849 struct btrfsic_block_link *l, *tmp; 2850 2851 list_for_each_entry_safe(l, tmp, &b_all->ref_to_list, 2852 node_ref_to) { 2853 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2854 btrfsic_print_rem_link(state, l); 2855 2856 l->ref_cnt--; 2857 if (0 == l->ref_cnt) 2858 btrfsic_block_link_free(l); 2859 } 2860 2861 if (b_all->is_iodone || b_all->never_written) 2862 btrfsic_block_free(b_all); 2863 else 2864 pr_info( 2865 "btrfs: attempt to free %c-block @%llu (%pg/%llu/%d) on umount which is not yet iodone!\n", 2866 btrfsic_get_block_type(state, b_all), 2867 b_all->logical_bytenr, b_all->dev_state->bdev, 2868 b_all->dev_bytenr, b_all->mirror_num); 2869 } 2870 2871 mutex_unlock(&btrfsic_mutex); 2872 2873 kvfree(state); 2874 } 2875