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/genhd.h> 82 #include <linux/blkdev.h> 83 #include <linux/mm.h> 84 #include <linux/string.h> 85 #include <crypto/hash.h> 86 #include "ctree.h" 87 #include "disk-io.h" 88 #include "transaction.h" 89 #include "extent_io.h" 90 #include "volumes.h" 91 #include "print-tree.h" 92 #include "locking.h" 93 #include "check-integrity.h" 94 #include "rcu-string.h" 95 #include "compression.h" 96 97 #define BTRFSIC_BLOCK_HASHTABLE_SIZE 0x10000 98 #define BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE 0x10000 99 #define BTRFSIC_DEV2STATE_HASHTABLE_SIZE 0x100 100 #define BTRFSIC_BLOCK_MAGIC_NUMBER 0x14491051 101 #define BTRFSIC_BLOCK_LINK_MAGIC_NUMBER 0x11070807 102 #define BTRFSIC_DEV2STATE_MAGIC_NUMBER 0x20111530 103 #define BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER 20111300 104 #define BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL (200 - 6) /* in characters, 105 * excluding " [...]" */ 106 #define BTRFSIC_GENERATION_UNKNOWN ((u64)-1) 107 108 /* 109 * The definition of the bitmask fields for the print_mask. 110 * They are specified with the mount option check_integrity_print_mask. 111 */ 112 #define BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE 0x00000001 113 #define BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION 0x00000002 114 #define BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE 0x00000004 115 #define BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE 0x00000008 116 #define BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH 0x00000010 117 #define BTRFSIC_PRINT_MASK_END_IO_BIO_BH 0x00000020 118 #define BTRFSIC_PRINT_MASK_VERBOSE 0x00000040 119 #define BTRFSIC_PRINT_MASK_VERY_VERBOSE 0x00000080 120 #define BTRFSIC_PRINT_MASK_INITIAL_TREE 0x00000100 121 #define BTRFSIC_PRINT_MASK_INITIAL_ALL_TREES 0x00000200 122 #define BTRFSIC_PRINT_MASK_INITIAL_DATABASE 0x00000400 123 #define BTRFSIC_PRINT_MASK_NUM_COPIES 0x00000800 124 #define BTRFSIC_PRINT_MASK_TREE_WITH_ALL_MIRRORS 0x00001000 125 #define BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE 0x00002000 126 127 struct btrfsic_dev_state; 128 struct btrfsic_state; 129 130 struct btrfsic_block { 131 u32 magic_num; /* only used for debug purposes */ 132 unsigned int is_metadata:1; /* if it is meta-data, not data-data */ 133 unsigned int is_superblock:1; /* if it is one of the superblocks */ 134 unsigned int is_iodone:1; /* if is done by lower subsystem */ 135 unsigned int iodone_w_error:1; /* error was indicated to endio */ 136 unsigned int never_written:1; /* block was added because it was 137 * referenced, not because it was 138 * written */ 139 unsigned int mirror_num; /* large enough to hold 140 * BTRFS_SUPER_MIRROR_MAX */ 141 struct btrfsic_dev_state *dev_state; 142 u64 dev_bytenr; /* key, physical byte num on disk */ 143 u64 logical_bytenr; /* logical byte num on disk */ 144 u64 generation; 145 struct btrfs_disk_key disk_key; /* extra info to print in case of 146 * issues, will not always be correct */ 147 struct list_head collision_resolving_node; /* list node */ 148 struct list_head all_blocks_node; /* list node */ 149 150 /* the following two lists contain block_link items */ 151 struct list_head ref_to_list; /* list */ 152 struct list_head ref_from_list; /* list */ 153 struct btrfsic_block *next_in_same_bio; 154 void *orig_bio_private; 155 bio_end_io_t *orig_bio_end_io; 156 int submit_bio_bh_rw; 157 u64 flush_gen; /* only valid if !never_written */ 158 }; 159 160 /* 161 * Elements of this type are allocated dynamically and required because 162 * each block object can refer to and can be ref from multiple blocks. 163 * The key to lookup them in the hashtable is the dev_bytenr of 164 * the block ref to plus the one from the block referred from. 165 * The fact that they are searchable via a hashtable and that a 166 * ref_cnt is maintained is not required for the btrfs integrity 167 * check algorithm itself, it is only used to make the output more 168 * beautiful in case that an error is detected (an error is defined 169 * as a write operation to a block while that block is still referenced). 170 */ 171 struct btrfsic_block_link { 172 u32 magic_num; /* only used for debug purposes */ 173 u32 ref_cnt; 174 struct list_head node_ref_to; /* list node */ 175 struct list_head node_ref_from; /* list node */ 176 struct list_head collision_resolving_node; /* list node */ 177 struct btrfsic_block *block_ref_to; 178 struct btrfsic_block *block_ref_from; 179 u64 parent_generation; 180 }; 181 182 struct btrfsic_dev_state { 183 u32 magic_num; /* only used for debug purposes */ 184 struct block_device *bdev; 185 struct btrfsic_state *state; 186 struct list_head collision_resolving_node; /* list node */ 187 struct btrfsic_block dummy_block_for_bio_bh_flush; 188 u64 last_flush_gen; 189 char name[BDEVNAME_SIZE]; 190 }; 191 192 struct btrfsic_block_hashtable { 193 struct list_head table[BTRFSIC_BLOCK_HASHTABLE_SIZE]; 194 }; 195 196 struct btrfsic_block_link_hashtable { 197 struct list_head table[BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE]; 198 }; 199 200 struct btrfsic_dev_state_hashtable { 201 struct list_head table[BTRFSIC_DEV2STATE_HASHTABLE_SIZE]; 202 }; 203 204 struct btrfsic_block_data_ctx { 205 u64 start; /* virtual bytenr */ 206 u64 dev_bytenr; /* physical bytenr on device */ 207 u32 len; 208 struct btrfsic_dev_state *dev; 209 char **datav; 210 struct page **pagev; 211 void *mem_to_free; 212 }; 213 214 /* This structure is used to implement recursion without occupying 215 * any stack space, refer to btrfsic_process_metablock() */ 216 struct btrfsic_stack_frame { 217 u32 magic; 218 u32 nr; 219 int error; 220 int i; 221 int limit_nesting; 222 int num_copies; 223 int mirror_num; 224 struct btrfsic_block *block; 225 struct btrfsic_block_data_ctx *block_ctx; 226 struct btrfsic_block *next_block; 227 struct btrfsic_block_data_ctx next_block_ctx; 228 struct btrfs_header *hdr; 229 struct btrfsic_stack_frame *prev; 230 }; 231 232 /* Some state per mounted filesystem */ 233 struct btrfsic_state { 234 u32 print_mask; 235 int include_extent_data; 236 struct list_head all_blocks_list; 237 struct btrfsic_block_hashtable block_hashtable; 238 struct btrfsic_block_link_hashtable block_link_hashtable; 239 struct btrfs_fs_info *fs_info; 240 u64 max_superblock_generation; 241 struct btrfsic_block *latest_superblock; 242 u32 metablock_size; 243 u32 datablock_size; 244 }; 245 246 static void btrfsic_block_init(struct btrfsic_block *b); 247 static struct btrfsic_block *btrfsic_block_alloc(void); 248 static void btrfsic_block_free(struct btrfsic_block *b); 249 static void btrfsic_block_link_init(struct btrfsic_block_link *n); 250 static struct btrfsic_block_link *btrfsic_block_link_alloc(void); 251 static void btrfsic_block_link_free(struct btrfsic_block_link *n); 252 static void btrfsic_dev_state_init(struct btrfsic_dev_state *ds); 253 static struct btrfsic_dev_state *btrfsic_dev_state_alloc(void); 254 static void btrfsic_dev_state_free(struct btrfsic_dev_state *ds); 255 static void btrfsic_block_hashtable_init(struct btrfsic_block_hashtable *h); 256 static void btrfsic_block_hashtable_add(struct btrfsic_block *b, 257 struct btrfsic_block_hashtable *h); 258 static void btrfsic_block_hashtable_remove(struct btrfsic_block *b); 259 static struct btrfsic_block *btrfsic_block_hashtable_lookup( 260 struct block_device *bdev, 261 u64 dev_bytenr, 262 struct btrfsic_block_hashtable *h); 263 static void btrfsic_block_link_hashtable_init( 264 struct btrfsic_block_link_hashtable *h); 265 static void btrfsic_block_link_hashtable_add( 266 struct btrfsic_block_link *l, 267 struct btrfsic_block_link_hashtable *h); 268 static void btrfsic_block_link_hashtable_remove(struct btrfsic_block_link *l); 269 static struct btrfsic_block_link *btrfsic_block_link_hashtable_lookup( 270 struct block_device *bdev_ref_to, 271 u64 dev_bytenr_ref_to, 272 struct block_device *bdev_ref_from, 273 u64 dev_bytenr_ref_from, 274 struct btrfsic_block_link_hashtable *h); 275 static void btrfsic_dev_state_hashtable_init( 276 struct btrfsic_dev_state_hashtable *h); 277 static void btrfsic_dev_state_hashtable_add( 278 struct btrfsic_dev_state *ds, 279 struct btrfsic_dev_state_hashtable *h); 280 static void btrfsic_dev_state_hashtable_remove(struct btrfsic_dev_state *ds); 281 static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(dev_t dev, 282 struct btrfsic_dev_state_hashtable *h); 283 static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void); 284 static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf); 285 static int btrfsic_process_superblock(struct btrfsic_state *state, 286 struct btrfs_fs_devices *fs_devices); 287 static int btrfsic_process_metablock(struct btrfsic_state *state, 288 struct btrfsic_block *block, 289 struct btrfsic_block_data_ctx *block_ctx, 290 int limit_nesting, int force_iodone_flag); 291 static void btrfsic_read_from_block_data( 292 struct btrfsic_block_data_ctx *block_ctx, 293 void *dst, u32 offset, size_t len); 294 static int btrfsic_create_link_to_next_block( 295 struct btrfsic_state *state, 296 struct btrfsic_block *block, 297 struct btrfsic_block_data_ctx 298 *block_ctx, u64 next_bytenr, 299 int limit_nesting, 300 struct btrfsic_block_data_ctx *next_block_ctx, 301 struct btrfsic_block **next_blockp, 302 int force_iodone_flag, 303 int *num_copiesp, int *mirror_nump, 304 struct btrfs_disk_key *disk_key, 305 u64 parent_generation); 306 static int btrfsic_handle_extent_data(struct btrfsic_state *state, 307 struct btrfsic_block *block, 308 struct btrfsic_block_data_ctx *block_ctx, 309 u32 item_offset, int force_iodone_flag); 310 static int btrfsic_map_block(struct btrfsic_state *state, u64 bytenr, u32 len, 311 struct btrfsic_block_data_ctx *block_ctx_out, 312 int mirror_num); 313 static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx); 314 static int btrfsic_read_block(struct btrfsic_state *state, 315 struct btrfsic_block_data_ctx *block_ctx); 316 static void btrfsic_dump_database(struct btrfsic_state *state); 317 static int btrfsic_test_for_metadata(struct btrfsic_state *state, 318 char **datav, unsigned int num_pages); 319 static void btrfsic_process_written_block(struct btrfsic_dev_state *dev_state, 320 u64 dev_bytenr, char **mapped_datav, 321 unsigned int num_pages, 322 struct bio *bio, int *bio_is_patched, 323 int submit_bio_bh_rw); 324 static int btrfsic_process_written_superblock( 325 struct btrfsic_state *state, 326 struct btrfsic_block *const block, 327 struct btrfs_super_block *const super_hdr); 328 static void btrfsic_bio_end_io(struct bio *bp); 329 static int btrfsic_is_block_ref_by_superblock(const struct btrfsic_state *state, 330 const struct btrfsic_block *block, 331 int recursion_level); 332 static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state, 333 struct btrfsic_block *const block, 334 int recursion_level); 335 static void btrfsic_print_add_link(const struct btrfsic_state *state, 336 const struct btrfsic_block_link *l); 337 static void btrfsic_print_rem_link(const struct btrfsic_state *state, 338 const struct btrfsic_block_link *l); 339 static char btrfsic_get_block_type(const struct btrfsic_state *state, 340 const struct btrfsic_block *block); 341 static void btrfsic_dump_tree(const struct btrfsic_state *state); 342 static void btrfsic_dump_tree_sub(const struct btrfsic_state *state, 343 const struct btrfsic_block *block, 344 int indent_level); 345 static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add( 346 struct btrfsic_state *state, 347 struct btrfsic_block_data_ctx *next_block_ctx, 348 struct btrfsic_block *next_block, 349 struct btrfsic_block *from_block, 350 u64 parent_generation); 351 static struct btrfsic_block *btrfsic_block_lookup_or_add( 352 struct btrfsic_state *state, 353 struct btrfsic_block_data_ctx *block_ctx, 354 const char *additional_string, 355 int is_metadata, 356 int is_iodone, 357 int never_written, 358 int mirror_num, 359 int *was_created); 360 static int btrfsic_process_superblock_dev_mirror( 361 struct btrfsic_state *state, 362 struct btrfsic_dev_state *dev_state, 363 struct btrfs_device *device, 364 int superblock_mirror_num, 365 struct btrfsic_dev_state **selected_dev_state, 366 struct btrfs_super_block *selected_super); 367 static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev); 368 static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state, 369 u64 bytenr, 370 struct btrfsic_dev_state *dev_state, 371 u64 dev_bytenr); 372 373 static struct mutex btrfsic_mutex; 374 static int btrfsic_is_initialized; 375 static struct btrfsic_dev_state_hashtable btrfsic_dev_state_hashtable; 376 377 378 static void btrfsic_block_init(struct btrfsic_block *b) 379 { 380 b->magic_num = BTRFSIC_BLOCK_MAGIC_NUMBER; 381 b->dev_state = NULL; 382 b->dev_bytenr = 0; 383 b->logical_bytenr = 0; 384 b->generation = BTRFSIC_GENERATION_UNKNOWN; 385 b->disk_key.objectid = 0; 386 b->disk_key.type = 0; 387 b->disk_key.offset = 0; 388 b->is_metadata = 0; 389 b->is_superblock = 0; 390 b->is_iodone = 0; 391 b->iodone_w_error = 0; 392 b->never_written = 0; 393 b->mirror_num = 0; 394 b->next_in_same_bio = NULL; 395 b->orig_bio_private = NULL; 396 b->orig_bio_end_io = NULL; 397 INIT_LIST_HEAD(&b->collision_resolving_node); 398 INIT_LIST_HEAD(&b->all_blocks_node); 399 INIT_LIST_HEAD(&b->ref_to_list); 400 INIT_LIST_HEAD(&b->ref_from_list); 401 b->submit_bio_bh_rw = 0; 402 b->flush_gen = 0; 403 } 404 405 static struct btrfsic_block *btrfsic_block_alloc(void) 406 { 407 struct btrfsic_block *b; 408 409 b = kzalloc(sizeof(*b), GFP_NOFS); 410 if (NULL != b) 411 btrfsic_block_init(b); 412 413 return b; 414 } 415 416 static void btrfsic_block_free(struct btrfsic_block *b) 417 { 418 BUG_ON(!(NULL == b || BTRFSIC_BLOCK_MAGIC_NUMBER == b->magic_num)); 419 kfree(b); 420 } 421 422 static void btrfsic_block_link_init(struct btrfsic_block_link *l) 423 { 424 l->magic_num = BTRFSIC_BLOCK_LINK_MAGIC_NUMBER; 425 l->ref_cnt = 1; 426 INIT_LIST_HEAD(&l->node_ref_to); 427 INIT_LIST_HEAD(&l->node_ref_from); 428 INIT_LIST_HEAD(&l->collision_resolving_node); 429 l->block_ref_to = NULL; 430 l->block_ref_from = NULL; 431 } 432 433 static struct btrfsic_block_link *btrfsic_block_link_alloc(void) 434 { 435 struct btrfsic_block_link *l; 436 437 l = kzalloc(sizeof(*l), GFP_NOFS); 438 if (NULL != l) 439 btrfsic_block_link_init(l); 440 441 return l; 442 } 443 444 static void btrfsic_block_link_free(struct btrfsic_block_link *l) 445 { 446 BUG_ON(!(NULL == l || BTRFSIC_BLOCK_LINK_MAGIC_NUMBER == l->magic_num)); 447 kfree(l); 448 } 449 450 static void btrfsic_dev_state_init(struct btrfsic_dev_state *ds) 451 { 452 ds->magic_num = BTRFSIC_DEV2STATE_MAGIC_NUMBER; 453 ds->bdev = NULL; 454 ds->state = NULL; 455 ds->name[0] = '\0'; 456 INIT_LIST_HEAD(&ds->collision_resolving_node); 457 ds->last_flush_gen = 0; 458 btrfsic_block_init(&ds->dummy_block_for_bio_bh_flush); 459 ds->dummy_block_for_bio_bh_flush.is_iodone = 1; 460 ds->dummy_block_for_bio_bh_flush.dev_state = ds; 461 } 462 463 static struct btrfsic_dev_state *btrfsic_dev_state_alloc(void) 464 { 465 struct btrfsic_dev_state *ds; 466 467 ds = kzalloc(sizeof(*ds), GFP_NOFS); 468 if (NULL != ds) 469 btrfsic_dev_state_init(ds); 470 471 return ds; 472 } 473 474 static void btrfsic_dev_state_free(struct btrfsic_dev_state *ds) 475 { 476 BUG_ON(!(NULL == ds || 477 BTRFSIC_DEV2STATE_MAGIC_NUMBER == ds->magic_num)); 478 kfree(ds); 479 } 480 481 static void btrfsic_block_hashtable_init(struct btrfsic_block_hashtable *h) 482 { 483 int i; 484 485 for (i = 0; i < BTRFSIC_BLOCK_HASHTABLE_SIZE; i++) 486 INIT_LIST_HEAD(h->table + i); 487 } 488 489 static void btrfsic_block_hashtable_add(struct btrfsic_block *b, 490 struct btrfsic_block_hashtable *h) 491 { 492 const unsigned int hashval = 493 (((unsigned int)(b->dev_bytenr >> 16)) ^ 494 ((unsigned int)((uintptr_t)b->dev_state->bdev))) & 495 (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1); 496 497 list_add(&b->collision_resolving_node, h->table + hashval); 498 } 499 500 static void btrfsic_block_hashtable_remove(struct btrfsic_block *b) 501 { 502 list_del(&b->collision_resolving_node); 503 } 504 505 static struct btrfsic_block *btrfsic_block_hashtable_lookup( 506 struct block_device *bdev, 507 u64 dev_bytenr, 508 struct btrfsic_block_hashtable *h) 509 { 510 const unsigned int hashval = 511 (((unsigned int)(dev_bytenr >> 16)) ^ 512 ((unsigned int)((uintptr_t)bdev))) & 513 (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1); 514 struct btrfsic_block *b; 515 516 list_for_each_entry(b, h->table + hashval, collision_resolving_node) { 517 if (b->dev_state->bdev == bdev && b->dev_bytenr == dev_bytenr) 518 return b; 519 } 520 521 return NULL; 522 } 523 524 static void btrfsic_block_link_hashtable_init( 525 struct btrfsic_block_link_hashtable *h) 526 { 527 int i; 528 529 for (i = 0; i < BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE; i++) 530 INIT_LIST_HEAD(h->table + i); 531 } 532 533 static void btrfsic_block_link_hashtable_add( 534 struct btrfsic_block_link *l, 535 struct btrfsic_block_link_hashtable *h) 536 { 537 const unsigned int hashval = 538 (((unsigned int)(l->block_ref_to->dev_bytenr >> 16)) ^ 539 ((unsigned int)(l->block_ref_from->dev_bytenr >> 16)) ^ 540 ((unsigned int)((uintptr_t)l->block_ref_to->dev_state->bdev)) ^ 541 ((unsigned int)((uintptr_t)l->block_ref_from->dev_state->bdev))) 542 & (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1); 543 544 BUG_ON(NULL == l->block_ref_to); 545 BUG_ON(NULL == l->block_ref_from); 546 list_add(&l->collision_resolving_node, h->table + hashval); 547 } 548 549 static void btrfsic_block_link_hashtable_remove(struct btrfsic_block_link *l) 550 { 551 list_del(&l->collision_resolving_node); 552 } 553 554 static struct btrfsic_block_link *btrfsic_block_link_hashtable_lookup( 555 struct block_device *bdev_ref_to, 556 u64 dev_bytenr_ref_to, 557 struct block_device *bdev_ref_from, 558 u64 dev_bytenr_ref_from, 559 struct btrfsic_block_link_hashtable *h) 560 { 561 const unsigned int hashval = 562 (((unsigned int)(dev_bytenr_ref_to >> 16)) ^ 563 ((unsigned int)(dev_bytenr_ref_from >> 16)) ^ 564 ((unsigned int)((uintptr_t)bdev_ref_to)) ^ 565 ((unsigned int)((uintptr_t)bdev_ref_from))) & 566 (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1); 567 struct btrfsic_block_link *l; 568 569 list_for_each_entry(l, h->table + hashval, collision_resolving_node) { 570 BUG_ON(NULL == l->block_ref_to); 571 BUG_ON(NULL == l->block_ref_from); 572 if (l->block_ref_to->dev_state->bdev == bdev_ref_to && 573 l->block_ref_to->dev_bytenr == dev_bytenr_ref_to && 574 l->block_ref_from->dev_state->bdev == bdev_ref_from && 575 l->block_ref_from->dev_bytenr == dev_bytenr_ref_from) 576 return l; 577 } 578 579 return NULL; 580 } 581 582 static void btrfsic_dev_state_hashtable_init( 583 struct btrfsic_dev_state_hashtable *h) 584 { 585 int i; 586 587 for (i = 0; i < BTRFSIC_DEV2STATE_HASHTABLE_SIZE; i++) 588 INIT_LIST_HEAD(h->table + i); 589 } 590 591 static void btrfsic_dev_state_hashtable_add( 592 struct btrfsic_dev_state *ds, 593 struct btrfsic_dev_state_hashtable *h) 594 { 595 const unsigned int hashval = 596 (((unsigned int)((uintptr_t)ds->bdev->bd_dev)) & 597 (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1)); 598 599 list_add(&ds->collision_resolving_node, h->table + hashval); 600 } 601 602 static void btrfsic_dev_state_hashtable_remove(struct btrfsic_dev_state *ds) 603 { 604 list_del(&ds->collision_resolving_node); 605 } 606 607 static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(dev_t dev, 608 struct btrfsic_dev_state_hashtable *h) 609 { 610 const unsigned int hashval = 611 dev & (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1); 612 struct btrfsic_dev_state *ds; 613 614 list_for_each_entry(ds, h->table + hashval, collision_resolving_node) { 615 if (ds->bdev->bd_dev == dev) 616 return ds; 617 } 618 619 return NULL; 620 } 621 622 static int btrfsic_process_superblock(struct btrfsic_state *state, 623 struct btrfs_fs_devices *fs_devices) 624 { 625 struct btrfs_super_block *selected_super; 626 struct list_head *dev_head = &fs_devices->devices; 627 struct btrfs_device *device; 628 struct btrfsic_dev_state *selected_dev_state = NULL; 629 int ret = 0; 630 int pass; 631 632 selected_super = kzalloc(sizeof(*selected_super), GFP_NOFS); 633 if (!selected_super) 634 return -ENOMEM; 635 636 list_for_each_entry(device, dev_head, dev_list) { 637 int i; 638 struct btrfsic_dev_state *dev_state; 639 640 if (!device->bdev || !device->name) 641 continue; 642 643 dev_state = btrfsic_dev_state_lookup(device->bdev->bd_dev); 644 BUG_ON(NULL == dev_state); 645 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) { 646 ret = btrfsic_process_superblock_dev_mirror( 647 state, dev_state, device, i, 648 &selected_dev_state, selected_super); 649 if (0 != ret && 0 == i) { 650 kfree(selected_super); 651 return ret; 652 } 653 } 654 } 655 656 if (NULL == state->latest_superblock) { 657 pr_info("btrfsic: no superblock found!\n"); 658 kfree(selected_super); 659 return -1; 660 } 661 662 for (pass = 0; pass < 3; pass++) { 663 int num_copies; 664 int mirror_num; 665 u64 next_bytenr; 666 667 switch (pass) { 668 case 0: 669 next_bytenr = btrfs_super_root(selected_super); 670 if (state->print_mask & 671 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 672 pr_info("root@%llu\n", next_bytenr); 673 break; 674 case 1: 675 next_bytenr = btrfs_super_chunk_root(selected_super); 676 if (state->print_mask & 677 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 678 pr_info("chunk@%llu\n", next_bytenr); 679 break; 680 case 2: 681 next_bytenr = btrfs_super_log_root(selected_super); 682 if (0 == next_bytenr) 683 continue; 684 if (state->print_mask & 685 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 686 pr_info("log@%llu\n", next_bytenr); 687 break; 688 } 689 690 num_copies = btrfs_num_copies(state->fs_info, next_bytenr, 691 state->metablock_size); 692 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 693 pr_info("num_copies(log_bytenr=%llu) = %d\n", 694 next_bytenr, num_copies); 695 696 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 697 struct btrfsic_block *next_block; 698 struct btrfsic_block_data_ctx tmp_next_block_ctx; 699 struct btrfsic_block_link *l; 700 701 ret = btrfsic_map_block(state, next_bytenr, 702 state->metablock_size, 703 &tmp_next_block_ctx, 704 mirror_num); 705 if (ret) { 706 pr_info("btrfsic: btrfsic_map_block(root @%llu, mirror %d) failed!\n", 707 next_bytenr, mirror_num); 708 kfree(selected_super); 709 return -1; 710 } 711 712 next_block = btrfsic_block_hashtable_lookup( 713 tmp_next_block_ctx.dev->bdev, 714 tmp_next_block_ctx.dev_bytenr, 715 &state->block_hashtable); 716 BUG_ON(NULL == next_block); 717 718 l = btrfsic_block_link_hashtable_lookup( 719 tmp_next_block_ctx.dev->bdev, 720 tmp_next_block_ctx.dev_bytenr, 721 state->latest_superblock->dev_state-> 722 bdev, 723 state->latest_superblock->dev_bytenr, 724 &state->block_link_hashtable); 725 BUG_ON(NULL == l); 726 727 ret = btrfsic_read_block(state, &tmp_next_block_ctx); 728 if (ret < (int)PAGE_SIZE) { 729 pr_info("btrfsic: read @logical %llu failed!\n", 730 tmp_next_block_ctx.start); 731 btrfsic_release_block_ctx(&tmp_next_block_ctx); 732 kfree(selected_super); 733 return -1; 734 } 735 736 ret = btrfsic_process_metablock(state, 737 next_block, 738 &tmp_next_block_ctx, 739 BTRFS_MAX_LEVEL + 3, 1); 740 btrfsic_release_block_ctx(&tmp_next_block_ctx); 741 } 742 } 743 744 kfree(selected_super); 745 return ret; 746 } 747 748 static int btrfsic_process_superblock_dev_mirror( 749 struct btrfsic_state *state, 750 struct btrfsic_dev_state *dev_state, 751 struct btrfs_device *device, 752 int superblock_mirror_num, 753 struct btrfsic_dev_state **selected_dev_state, 754 struct btrfs_super_block *selected_super) 755 { 756 struct btrfs_fs_info *fs_info = state->fs_info; 757 struct btrfs_super_block *super_tmp; 758 u64 dev_bytenr; 759 struct btrfsic_block *superblock_tmp; 760 int pass; 761 struct block_device *const superblock_bdev = device->bdev; 762 struct page *page; 763 struct address_space *mapping = superblock_bdev->bd_inode->i_mapping; 764 int ret = 0; 765 766 /* super block bytenr is always the unmapped device bytenr */ 767 dev_bytenr = btrfs_sb_offset(superblock_mirror_num); 768 if (dev_bytenr + BTRFS_SUPER_INFO_SIZE > device->commit_total_bytes) 769 return -1; 770 771 page = read_cache_page_gfp(mapping, dev_bytenr >> PAGE_SHIFT, GFP_NOFS); 772 if (IS_ERR(page)) 773 return -1; 774 775 super_tmp = page_address(page); 776 777 if (btrfs_super_bytenr(super_tmp) != dev_bytenr || 778 btrfs_super_magic(super_tmp) != BTRFS_MAGIC || 779 memcmp(device->uuid, super_tmp->dev_item.uuid, BTRFS_UUID_SIZE) || 780 btrfs_super_nodesize(super_tmp) != state->metablock_size || 781 btrfs_super_sectorsize(super_tmp) != state->datablock_size) { 782 ret = 0; 783 goto out; 784 } 785 786 superblock_tmp = 787 btrfsic_block_hashtable_lookup(superblock_bdev, 788 dev_bytenr, 789 &state->block_hashtable); 790 if (NULL == superblock_tmp) { 791 superblock_tmp = btrfsic_block_alloc(); 792 if (NULL == superblock_tmp) { 793 ret = -1; 794 goto out; 795 } 796 /* for superblock, only the dev_bytenr makes sense */ 797 superblock_tmp->dev_bytenr = dev_bytenr; 798 superblock_tmp->dev_state = dev_state; 799 superblock_tmp->logical_bytenr = dev_bytenr; 800 superblock_tmp->generation = btrfs_super_generation(super_tmp); 801 superblock_tmp->is_metadata = 1; 802 superblock_tmp->is_superblock = 1; 803 superblock_tmp->is_iodone = 1; 804 superblock_tmp->never_written = 0; 805 superblock_tmp->mirror_num = 1 + superblock_mirror_num; 806 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE) 807 btrfs_info_in_rcu(fs_info, 808 "new initial S-block (bdev %p, %s) @%llu (%s/%llu/%d)", 809 superblock_bdev, 810 rcu_str_deref(device->name), dev_bytenr, 811 dev_state->name, dev_bytenr, 812 superblock_mirror_num); 813 list_add(&superblock_tmp->all_blocks_node, 814 &state->all_blocks_list); 815 btrfsic_block_hashtable_add(superblock_tmp, 816 &state->block_hashtable); 817 } 818 819 /* select the one with the highest generation field */ 820 if (btrfs_super_generation(super_tmp) > 821 state->max_superblock_generation || 822 0 == state->max_superblock_generation) { 823 memcpy(selected_super, super_tmp, sizeof(*selected_super)); 824 *selected_dev_state = dev_state; 825 state->max_superblock_generation = 826 btrfs_super_generation(super_tmp); 827 state->latest_superblock = superblock_tmp; 828 } 829 830 for (pass = 0; pass < 3; pass++) { 831 u64 next_bytenr; 832 int num_copies; 833 int mirror_num; 834 const char *additional_string = NULL; 835 struct btrfs_disk_key tmp_disk_key; 836 837 tmp_disk_key.type = BTRFS_ROOT_ITEM_KEY; 838 tmp_disk_key.offset = 0; 839 switch (pass) { 840 case 0: 841 btrfs_set_disk_key_objectid(&tmp_disk_key, 842 BTRFS_ROOT_TREE_OBJECTID); 843 additional_string = "initial root "; 844 next_bytenr = btrfs_super_root(super_tmp); 845 break; 846 case 1: 847 btrfs_set_disk_key_objectid(&tmp_disk_key, 848 BTRFS_CHUNK_TREE_OBJECTID); 849 additional_string = "initial chunk "; 850 next_bytenr = btrfs_super_chunk_root(super_tmp); 851 break; 852 case 2: 853 btrfs_set_disk_key_objectid(&tmp_disk_key, 854 BTRFS_TREE_LOG_OBJECTID); 855 additional_string = "initial log "; 856 next_bytenr = btrfs_super_log_root(super_tmp); 857 if (0 == next_bytenr) 858 continue; 859 break; 860 } 861 862 num_copies = btrfs_num_copies(fs_info, next_bytenr, 863 state->metablock_size); 864 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 865 pr_info("num_copies(log_bytenr=%llu) = %d\n", 866 next_bytenr, num_copies); 867 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 868 struct btrfsic_block *next_block; 869 struct btrfsic_block_data_ctx tmp_next_block_ctx; 870 struct btrfsic_block_link *l; 871 872 if (btrfsic_map_block(state, next_bytenr, 873 state->metablock_size, 874 &tmp_next_block_ctx, 875 mirror_num)) { 876 pr_info("btrfsic: btrfsic_map_block(bytenr @%llu, mirror %d) failed!\n", 877 next_bytenr, mirror_num); 878 ret = -1; 879 goto out; 880 } 881 882 next_block = btrfsic_block_lookup_or_add( 883 state, &tmp_next_block_ctx, 884 additional_string, 1, 1, 0, 885 mirror_num, NULL); 886 if (NULL == next_block) { 887 btrfsic_release_block_ctx(&tmp_next_block_ctx); 888 ret = -1; 889 goto out; 890 } 891 892 next_block->disk_key = tmp_disk_key; 893 next_block->generation = BTRFSIC_GENERATION_UNKNOWN; 894 l = btrfsic_block_link_lookup_or_add( 895 state, &tmp_next_block_ctx, 896 next_block, superblock_tmp, 897 BTRFSIC_GENERATION_UNKNOWN); 898 btrfsic_release_block_ctx(&tmp_next_block_ctx); 899 if (NULL == l) { 900 ret = -1; 901 goto out; 902 } 903 } 904 } 905 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_ALL_TREES) 906 btrfsic_dump_tree_sub(state, superblock_tmp, 0); 907 908 out: 909 put_page(page); 910 return ret; 911 } 912 913 static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void) 914 { 915 struct btrfsic_stack_frame *sf; 916 917 sf = kzalloc(sizeof(*sf), GFP_NOFS); 918 if (sf) 919 sf->magic = BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER; 920 return sf; 921 } 922 923 static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf) 924 { 925 BUG_ON(!(NULL == sf || 926 BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER == sf->magic)); 927 kfree(sf); 928 } 929 930 static noinline_for_stack int btrfsic_process_metablock( 931 struct btrfsic_state *state, 932 struct btrfsic_block *const first_block, 933 struct btrfsic_block_data_ctx *const first_block_ctx, 934 int first_limit_nesting, int force_iodone_flag) 935 { 936 struct btrfsic_stack_frame initial_stack_frame = { 0 }; 937 struct btrfsic_stack_frame *sf; 938 struct btrfsic_stack_frame *next_stack; 939 struct btrfs_header *const first_hdr = 940 (struct btrfs_header *)first_block_ctx->datav[0]; 941 942 BUG_ON(!first_hdr); 943 sf = &initial_stack_frame; 944 sf->error = 0; 945 sf->i = -1; 946 sf->limit_nesting = first_limit_nesting; 947 sf->block = first_block; 948 sf->block_ctx = first_block_ctx; 949 sf->next_block = NULL; 950 sf->hdr = first_hdr; 951 sf->prev = NULL; 952 953 continue_with_new_stack_frame: 954 sf->block->generation = btrfs_stack_header_generation(sf->hdr); 955 if (0 == sf->hdr->level) { 956 struct btrfs_leaf *const leafhdr = 957 (struct btrfs_leaf *)sf->hdr; 958 959 if (-1 == sf->i) { 960 sf->nr = btrfs_stack_header_nritems(&leafhdr->header); 961 962 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 963 pr_info("leaf %llu items %d generation %llu owner %llu\n", 964 sf->block_ctx->start, sf->nr, 965 btrfs_stack_header_generation( 966 &leafhdr->header), 967 btrfs_stack_header_owner( 968 &leafhdr->header)); 969 } 970 971 continue_with_current_leaf_stack_frame: 972 if (0 == sf->num_copies || sf->mirror_num > sf->num_copies) { 973 sf->i++; 974 sf->num_copies = 0; 975 } 976 977 if (sf->i < sf->nr) { 978 struct btrfs_item disk_item; 979 u32 disk_item_offset = 980 (uintptr_t)(leafhdr->items + sf->i) - 981 (uintptr_t)leafhdr; 982 struct btrfs_disk_key *disk_key; 983 u8 type; 984 u32 item_offset; 985 u32 item_size; 986 987 if (disk_item_offset + sizeof(struct btrfs_item) > 988 sf->block_ctx->len) { 989 leaf_item_out_of_bounce_error: 990 pr_info("btrfsic: leaf item out of bounce at logical %llu, dev %s\n", 991 sf->block_ctx->start, 992 sf->block_ctx->dev->name); 993 goto one_stack_frame_backwards; 994 } 995 btrfsic_read_from_block_data(sf->block_ctx, 996 &disk_item, 997 disk_item_offset, 998 sizeof(struct btrfs_item)); 999 item_offset = btrfs_stack_item_offset(&disk_item); 1000 item_size = btrfs_stack_item_size(&disk_item); 1001 disk_key = &disk_item.key; 1002 type = btrfs_disk_key_type(disk_key); 1003 1004 if (BTRFS_ROOT_ITEM_KEY == type) { 1005 struct btrfs_root_item root_item; 1006 u32 root_item_offset; 1007 u64 next_bytenr; 1008 1009 root_item_offset = item_offset + 1010 offsetof(struct btrfs_leaf, items); 1011 if (root_item_offset + item_size > 1012 sf->block_ctx->len) 1013 goto leaf_item_out_of_bounce_error; 1014 btrfsic_read_from_block_data( 1015 sf->block_ctx, &root_item, 1016 root_item_offset, 1017 item_size); 1018 next_bytenr = btrfs_root_bytenr(&root_item); 1019 1020 sf->error = 1021 btrfsic_create_link_to_next_block( 1022 state, 1023 sf->block, 1024 sf->block_ctx, 1025 next_bytenr, 1026 sf->limit_nesting, 1027 &sf->next_block_ctx, 1028 &sf->next_block, 1029 force_iodone_flag, 1030 &sf->num_copies, 1031 &sf->mirror_num, 1032 disk_key, 1033 btrfs_root_generation( 1034 &root_item)); 1035 if (sf->error) 1036 goto one_stack_frame_backwards; 1037 1038 if (NULL != sf->next_block) { 1039 struct btrfs_header *const next_hdr = 1040 (struct btrfs_header *) 1041 sf->next_block_ctx.datav[0]; 1042 1043 next_stack = 1044 btrfsic_stack_frame_alloc(); 1045 if (NULL == next_stack) { 1046 sf->error = -1; 1047 btrfsic_release_block_ctx( 1048 &sf-> 1049 next_block_ctx); 1050 goto one_stack_frame_backwards; 1051 } 1052 1053 next_stack->i = -1; 1054 next_stack->block = sf->next_block; 1055 next_stack->block_ctx = 1056 &sf->next_block_ctx; 1057 next_stack->next_block = NULL; 1058 next_stack->hdr = next_hdr; 1059 next_stack->limit_nesting = 1060 sf->limit_nesting - 1; 1061 next_stack->prev = sf; 1062 sf = next_stack; 1063 goto continue_with_new_stack_frame; 1064 } 1065 } else if (BTRFS_EXTENT_DATA_KEY == type && 1066 state->include_extent_data) { 1067 sf->error = btrfsic_handle_extent_data( 1068 state, 1069 sf->block, 1070 sf->block_ctx, 1071 item_offset, 1072 force_iodone_flag); 1073 if (sf->error) 1074 goto one_stack_frame_backwards; 1075 } 1076 1077 goto continue_with_current_leaf_stack_frame; 1078 } 1079 } else { 1080 struct btrfs_node *const nodehdr = (struct btrfs_node *)sf->hdr; 1081 1082 if (-1 == sf->i) { 1083 sf->nr = btrfs_stack_header_nritems(&nodehdr->header); 1084 1085 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1086 pr_info("node %llu level %d items %d generation %llu owner %llu\n", 1087 sf->block_ctx->start, 1088 nodehdr->header.level, sf->nr, 1089 btrfs_stack_header_generation( 1090 &nodehdr->header), 1091 btrfs_stack_header_owner( 1092 &nodehdr->header)); 1093 } 1094 1095 continue_with_current_node_stack_frame: 1096 if (0 == sf->num_copies || sf->mirror_num > sf->num_copies) { 1097 sf->i++; 1098 sf->num_copies = 0; 1099 } 1100 1101 if (sf->i < sf->nr) { 1102 struct btrfs_key_ptr key_ptr; 1103 u32 key_ptr_offset; 1104 u64 next_bytenr; 1105 1106 key_ptr_offset = (uintptr_t)(nodehdr->ptrs + sf->i) - 1107 (uintptr_t)nodehdr; 1108 if (key_ptr_offset + sizeof(struct btrfs_key_ptr) > 1109 sf->block_ctx->len) { 1110 pr_info("btrfsic: node item out of bounce at logical %llu, dev %s\n", 1111 sf->block_ctx->start, 1112 sf->block_ctx->dev->name); 1113 goto one_stack_frame_backwards; 1114 } 1115 btrfsic_read_from_block_data( 1116 sf->block_ctx, &key_ptr, key_ptr_offset, 1117 sizeof(struct btrfs_key_ptr)); 1118 next_bytenr = btrfs_stack_key_blockptr(&key_ptr); 1119 1120 sf->error = btrfsic_create_link_to_next_block( 1121 state, 1122 sf->block, 1123 sf->block_ctx, 1124 next_bytenr, 1125 sf->limit_nesting, 1126 &sf->next_block_ctx, 1127 &sf->next_block, 1128 force_iodone_flag, 1129 &sf->num_copies, 1130 &sf->mirror_num, 1131 &key_ptr.key, 1132 btrfs_stack_key_generation(&key_ptr)); 1133 if (sf->error) 1134 goto one_stack_frame_backwards; 1135 1136 if (NULL != sf->next_block) { 1137 struct btrfs_header *const next_hdr = 1138 (struct btrfs_header *) 1139 sf->next_block_ctx.datav[0]; 1140 1141 next_stack = btrfsic_stack_frame_alloc(); 1142 if (NULL == next_stack) { 1143 sf->error = -1; 1144 goto one_stack_frame_backwards; 1145 } 1146 1147 next_stack->i = -1; 1148 next_stack->block = sf->next_block; 1149 next_stack->block_ctx = &sf->next_block_ctx; 1150 next_stack->next_block = NULL; 1151 next_stack->hdr = next_hdr; 1152 next_stack->limit_nesting = 1153 sf->limit_nesting - 1; 1154 next_stack->prev = sf; 1155 sf = next_stack; 1156 goto continue_with_new_stack_frame; 1157 } 1158 1159 goto continue_with_current_node_stack_frame; 1160 } 1161 } 1162 1163 one_stack_frame_backwards: 1164 if (NULL != sf->prev) { 1165 struct btrfsic_stack_frame *const prev = sf->prev; 1166 1167 /* the one for the initial block is freed in the caller */ 1168 btrfsic_release_block_ctx(sf->block_ctx); 1169 1170 if (sf->error) { 1171 prev->error = sf->error; 1172 btrfsic_stack_frame_free(sf); 1173 sf = prev; 1174 goto one_stack_frame_backwards; 1175 } 1176 1177 btrfsic_stack_frame_free(sf); 1178 sf = prev; 1179 goto continue_with_new_stack_frame; 1180 } else { 1181 BUG_ON(&initial_stack_frame != sf); 1182 } 1183 1184 return sf->error; 1185 } 1186 1187 static void btrfsic_read_from_block_data( 1188 struct btrfsic_block_data_ctx *block_ctx, 1189 void *dstv, u32 offset, size_t len) 1190 { 1191 size_t cur; 1192 size_t pgoff; 1193 char *kaddr; 1194 char *dst = (char *)dstv; 1195 size_t start_offset = offset_in_page(block_ctx->start); 1196 unsigned long i = (start_offset + offset) >> PAGE_SHIFT; 1197 1198 WARN_ON(offset + len > block_ctx->len); 1199 pgoff = offset_in_page(start_offset + offset); 1200 1201 while (len > 0) { 1202 cur = min(len, ((size_t)PAGE_SIZE - pgoff)); 1203 BUG_ON(i >= DIV_ROUND_UP(block_ctx->len, PAGE_SIZE)); 1204 kaddr = block_ctx->datav[i]; 1205 memcpy(dst, kaddr + pgoff, cur); 1206 1207 dst += cur; 1208 len -= cur; 1209 pgoff = 0; 1210 i++; 1211 } 1212 } 1213 1214 static int btrfsic_create_link_to_next_block( 1215 struct btrfsic_state *state, 1216 struct btrfsic_block *block, 1217 struct btrfsic_block_data_ctx *block_ctx, 1218 u64 next_bytenr, 1219 int limit_nesting, 1220 struct btrfsic_block_data_ctx *next_block_ctx, 1221 struct btrfsic_block **next_blockp, 1222 int force_iodone_flag, 1223 int *num_copiesp, int *mirror_nump, 1224 struct btrfs_disk_key *disk_key, 1225 u64 parent_generation) 1226 { 1227 struct btrfs_fs_info *fs_info = state->fs_info; 1228 struct btrfsic_block *next_block = NULL; 1229 int ret; 1230 struct btrfsic_block_link *l; 1231 int did_alloc_block_link; 1232 int block_was_created; 1233 1234 *next_blockp = NULL; 1235 if (0 == *num_copiesp) { 1236 *num_copiesp = btrfs_num_copies(fs_info, next_bytenr, 1237 state->metablock_size); 1238 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 1239 pr_info("num_copies(log_bytenr=%llu) = %d\n", 1240 next_bytenr, *num_copiesp); 1241 *mirror_nump = 1; 1242 } 1243 1244 if (*mirror_nump > *num_copiesp) 1245 return 0; 1246 1247 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1248 pr_info("btrfsic_create_link_to_next_block(mirror_num=%d)\n", 1249 *mirror_nump); 1250 ret = btrfsic_map_block(state, next_bytenr, 1251 state->metablock_size, 1252 next_block_ctx, *mirror_nump); 1253 if (ret) { 1254 pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n", 1255 next_bytenr, *mirror_nump); 1256 btrfsic_release_block_ctx(next_block_ctx); 1257 *next_blockp = NULL; 1258 return -1; 1259 } 1260 1261 next_block = btrfsic_block_lookup_or_add(state, 1262 next_block_ctx, "referenced ", 1263 1, force_iodone_flag, 1264 !force_iodone_flag, 1265 *mirror_nump, 1266 &block_was_created); 1267 if (NULL == next_block) { 1268 btrfsic_release_block_ctx(next_block_ctx); 1269 *next_blockp = NULL; 1270 return -1; 1271 } 1272 if (block_was_created) { 1273 l = NULL; 1274 next_block->generation = BTRFSIC_GENERATION_UNKNOWN; 1275 } else { 1276 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) { 1277 if (next_block->logical_bytenr != next_bytenr && 1278 !(!next_block->is_metadata && 1279 0 == next_block->logical_bytenr)) 1280 pr_info("Referenced block @%llu (%s/%llu/%d) found in hash table, %c, bytenr mismatch (!= stored %llu).\n", 1281 next_bytenr, next_block_ctx->dev->name, 1282 next_block_ctx->dev_bytenr, *mirror_nump, 1283 btrfsic_get_block_type(state, 1284 next_block), 1285 next_block->logical_bytenr); 1286 else 1287 pr_info("Referenced block @%llu (%s/%llu/%d) found in hash table, %c.\n", 1288 next_bytenr, next_block_ctx->dev->name, 1289 next_block_ctx->dev_bytenr, *mirror_nump, 1290 btrfsic_get_block_type(state, 1291 next_block)); 1292 } 1293 next_block->logical_bytenr = next_bytenr; 1294 1295 next_block->mirror_num = *mirror_nump; 1296 l = btrfsic_block_link_hashtable_lookup( 1297 next_block_ctx->dev->bdev, 1298 next_block_ctx->dev_bytenr, 1299 block_ctx->dev->bdev, 1300 block_ctx->dev_bytenr, 1301 &state->block_link_hashtable); 1302 } 1303 1304 next_block->disk_key = *disk_key; 1305 if (NULL == l) { 1306 l = btrfsic_block_link_alloc(); 1307 if (NULL == l) { 1308 btrfsic_release_block_ctx(next_block_ctx); 1309 *next_blockp = NULL; 1310 return -1; 1311 } 1312 1313 did_alloc_block_link = 1; 1314 l->block_ref_to = next_block; 1315 l->block_ref_from = block; 1316 l->ref_cnt = 1; 1317 l->parent_generation = parent_generation; 1318 1319 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1320 btrfsic_print_add_link(state, l); 1321 1322 list_add(&l->node_ref_to, &block->ref_to_list); 1323 list_add(&l->node_ref_from, &next_block->ref_from_list); 1324 1325 btrfsic_block_link_hashtable_add(l, 1326 &state->block_link_hashtable); 1327 } else { 1328 did_alloc_block_link = 0; 1329 if (0 == limit_nesting) { 1330 l->ref_cnt++; 1331 l->parent_generation = parent_generation; 1332 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1333 btrfsic_print_add_link(state, l); 1334 } 1335 } 1336 1337 if (limit_nesting > 0 && did_alloc_block_link) { 1338 ret = btrfsic_read_block(state, next_block_ctx); 1339 if (ret < (int)next_block_ctx->len) { 1340 pr_info("btrfsic: read block @logical %llu failed!\n", 1341 next_bytenr); 1342 btrfsic_release_block_ctx(next_block_ctx); 1343 *next_blockp = NULL; 1344 return -1; 1345 } 1346 1347 *next_blockp = next_block; 1348 } else { 1349 *next_blockp = NULL; 1350 } 1351 (*mirror_nump)++; 1352 1353 return 0; 1354 } 1355 1356 static int btrfsic_handle_extent_data( 1357 struct btrfsic_state *state, 1358 struct btrfsic_block *block, 1359 struct btrfsic_block_data_ctx *block_ctx, 1360 u32 item_offset, int force_iodone_flag) 1361 { 1362 struct btrfs_fs_info *fs_info = state->fs_info; 1363 struct btrfs_file_extent_item file_extent_item; 1364 u64 file_extent_item_offset; 1365 u64 next_bytenr; 1366 u64 num_bytes; 1367 u64 generation; 1368 struct btrfsic_block_link *l; 1369 int ret; 1370 1371 file_extent_item_offset = offsetof(struct btrfs_leaf, items) + 1372 item_offset; 1373 if (file_extent_item_offset + 1374 offsetof(struct btrfs_file_extent_item, disk_num_bytes) > 1375 block_ctx->len) { 1376 pr_info("btrfsic: file item out of bounce at logical %llu, dev %s\n", 1377 block_ctx->start, block_ctx->dev->name); 1378 return -1; 1379 } 1380 1381 btrfsic_read_from_block_data(block_ctx, &file_extent_item, 1382 file_extent_item_offset, 1383 offsetof(struct btrfs_file_extent_item, disk_num_bytes)); 1384 if (BTRFS_FILE_EXTENT_REG != file_extent_item.type || 1385 btrfs_stack_file_extent_disk_bytenr(&file_extent_item) == 0) { 1386 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE) 1387 pr_info("extent_data: type %u, disk_bytenr = %llu\n", 1388 file_extent_item.type, 1389 btrfs_stack_file_extent_disk_bytenr( 1390 &file_extent_item)); 1391 return 0; 1392 } 1393 1394 if (file_extent_item_offset + sizeof(struct btrfs_file_extent_item) > 1395 block_ctx->len) { 1396 pr_info("btrfsic: file item out of bounce at logical %llu, dev %s\n", 1397 block_ctx->start, block_ctx->dev->name); 1398 return -1; 1399 } 1400 btrfsic_read_from_block_data(block_ctx, &file_extent_item, 1401 file_extent_item_offset, 1402 sizeof(struct btrfs_file_extent_item)); 1403 next_bytenr = btrfs_stack_file_extent_disk_bytenr(&file_extent_item); 1404 if (btrfs_stack_file_extent_compression(&file_extent_item) == 1405 BTRFS_COMPRESS_NONE) { 1406 next_bytenr += btrfs_stack_file_extent_offset(&file_extent_item); 1407 num_bytes = btrfs_stack_file_extent_num_bytes(&file_extent_item); 1408 } else { 1409 num_bytes = btrfs_stack_file_extent_disk_num_bytes(&file_extent_item); 1410 } 1411 generation = btrfs_stack_file_extent_generation(&file_extent_item); 1412 1413 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE) 1414 pr_info("extent_data: type %u, disk_bytenr = %llu, offset = %llu, num_bytes = %llu\n", 1415 file_extent_item.type, 1416 btrfs_stack_file_extent_disk_bytenr(&file_extent_item), 1417 btrfs_stack_file_extent_offset(&file_extent_item), 1418 num_bytes); 1419 while (num_bytes > 0) { 1420 u32 chunk_len; 1421 int num_copies; 1422 int mirror_num; 1423 1424 if (num_bytes > state->datablock_size) 1425 chunk_len = state->datablock_size; 1426 else 1427 chunk_len = num_bytes; 1428 1429 num_copies = btrfs_num_copies(fs_info, next_bytenr, 1430 state->datablock_size); 1431 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 1432 pr_info("num_copies(log_bytenr=%llu) = %d\n", 1433 next_bytenr, num_copies); 1434 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 1435 struct btrfsic_block_data_ctx next_block_ctx; 1436 struct btrfsic_block *next_block; 1437 int block_was_created; 1438 1439 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1440 pr_info("btrfsic_handle_extent_data(mirror_num=%d)\n", 1441 mirror_num); 1442 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE) 1443 pr_info("\tdisk_bytenr = %llu, num_bytes %u\n", 1444 next_bytenr, chunk_len); 1445 ret = btrfsic_map_block(state, next_bytenr, 1446 chunk_len, &next_block_ctx, 1447 mirror_num); 1448 if (ret) { 1449 pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n", 1450 next_bytenr, mirror_num); 1451 return -1; 1452 } 1453 1454 next_block = btrfsic_block_lookup_or_add( 1455 state, 1456 &next_block_ctx, 1457 "referenced ", 1458 0, 1459 force_iodone_flag, 1460 !force_iodone_flag, 1461 mirror_num, 1462 &block_was_created); 1463 if (NULL == next_block) { 1464 btrfsic_release_block_ctx(&next_block_ctx); 1465 return -1; 1466 } 1467 if (!block_was_created) { 1468 if ((state->print_mask & 1469 BTRFSIC_PRINT_MASK_VERBOSE) && 1470 next_block->logical_bytenr != next_bytenr && 1471 !(!next_block->is_metadata && 1472 0 == next_block->logical_bytenr)) { 1473 pr_info("Referenced block @%llu (%s/%llu/%d) found in hash table, D, bytenr mismatch (!= stored %llu).\n", 1474 next_bytenr, 1475 next_block_ctx.dev->name, 1476 next_block_ctx.dev_bytenr, 1477 mirror_num, 1478 next_block->logical_bytenr); 1479 } 1480 next_block->logical_bytenr = next_bytenr; 1481 next_block->mirror_num = mirror_num; 1482 } 1483 1484 l = btrfsic_block_link_lookup_or_add(state, 1485 &next_block_ctx, 1486 next_block, block, 1487 generation); 1488 btrfsic_release_block_ctx(&next_block_ctx); 1489 if (NULL == l) 1490 return -1; 1491 } 1492 1493 next_bytenr += chunk_len; 1494 num_bytes -= chunk_len; 1495 } 1496 1497 return 0; 1498 } 1499 1500 static int btrfsic_map_block(struct btrfsic_state *state, u64 bytenr, u32 len, 1501 struct btrfsic_block_data_ctx *block_ctx_out, 1502 int mirror_num) 1503 { 1504 struct btrfs_fs_info *fs_info = state->fs_info; 1505 int ret; 1506 u64 length; 1507 struct btrfs_bio *multi = NULL; 1508 struct btrfs_device *device; 1509 1510 length = len; 1511 ret = btrfs_map_block(fs_info, BTRFS_MAP_READ, 1512 bytenr, &length, &multi, mirror_num); 1513 1514 if (ret) { 1515 block_ctx_out->start = 0; 1516 block_ctx_out->dev_bytenr = 0; 1517 block_ctx_out->len = 0; 1518 block_ctx_out->dev = NULL; 1519 block_ctx_out->datav = NULL; 1520 block_ctx_out->pagev = NULL; 1521 block_ctx_out->mem_to_free = NULL; 1522 1523 return ret; 1524 } 1525 1526 device = multi->stripes[0].dev; 1527 if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state) || 1528 !device->bdev || !device->name) 1529 block_ctx_out->dev = NULL; 1530 else 1531 block_ctx_out->dev = btrfsic_dev_state_lookup( 1532 device->bdev->bd_dev); 1533 block_ctx_out->dev_bytenr = multi->stripes[0].physical; 1534 block_ctx_out->start = bytenr; 1535 block_ctx_out->len = len; 1536 block_ctx_out->datav = NULL; 1537 block_ctx_out->pagev = NULL; 1538 block_ctx_out->mem_to_free = NULL; 1539 1540 kfree(multi); 1541 if (NULL == block_ctx_out->dev) { 1542 ret = -ENXIO; 1543 pr_info("btrfsic: error, cannot lookup dev (#1)!\n"); 1544 } 1545 1546 return ret; 1547 } 1548 1549 static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx) 1550 { 1551 if (block_ctx->mem_to_free) { 1552 unsigned int num_pages; 1553 1554 BUG_ON(!block_ctx->datav); 1555 BUG_ON(!block_ctx->pagev); 1556 num_pages = (block_ctx->len + (u64)PAGE_SIZE - 1) >> 1557 PAGE_SHIFT; 1558 while (num_pages > 0) { 1559 num_pages--; 1560 if (block_ctx->datav[num_pages]) { 1561 kunmap(block_ctx->pagev[num_pages]); 1562 block_ctx->datav[num_pages] = NULL; 1563 } 1564 if (block_ctx->pagev[num_pages]) { 1565 __free_page(block_ctx->pagev[num_pages]); 1566 block_ctx->pagev[num_pages] = NULL; 1567 } 1568 } 1569 1570 kfree(block_ctx->mem_to_free); 1571 block_ctx->mem_to_free = NULL; 1572 block_ctx->pagev = NULL; 1573 block_ctx->datav = NULL; 1574 } 1575 } 1576 1577 static int btrfsic_read_block(struct btrfsic_state *state, 1578 struct btrfsic_block_data_ctx *block_ctx) 1579 { 1580 unsigned int num_pages; 1581 unsigned int i; 1582 size_t size; 1583 u64 dev_bytenr; 1584 int ret; 1585 1586 BUG_ON(block_ctx->datav); 1587 BUG_ON(block_ctx->pagev); 1588 BUG_ON(block_ctx->mem_to_free); 1589 if (!PAGE_ALIGNED(block_ctx->dev_bytenr)) { 1590 pr_info("btrfsic: read_block() with unaligned bytenr %llu\n", 1591 block_ctx->dev_bytenr); 1592 return -1; 1593 } 1594 1595 num_pages = (block_ctx->len + (u64)PAGE_SIZE - 1) >> 1596 PAGE_SHIFT; 1597 size = sizeof(*block_ctx->datav) + sizeof(*block_ctx->pagev); 1598 block_ctx->mem_to_free = kcalloc(num_pages, size, GFP_NOFS); 1599 if (!block_ctx->mem_to_free) 1600 return -ENOMEM; 1601 block_ctx->datav = block_ctx->mem_to_free; 1602 block_ctx->pagev = (struct page **)(block_ctx->datav + num_pages); 1603 for (i = 0; i < num_pages; i++) { 1604 block_ctx->pagev[i] = alloc_page(GFP_NOFS); 1605 if (!block_ctx->pagev[i]) 1606 return -1; 1607 } 1608 1609 dev_bytenr = block_ctx->dev_bytenr; 1610 for (i = 0; i < num_pages;) { 1611 struct bio *bio; 1612 unsigned int j; 1613 1614 bio = btrfs_io_bio_alloc(num_pages - i); 1615 bio_set_dev(bio, block_ctx->dev->bdev); 1616 bio->bi_iter.bi_sector = dev_bytenr >> 9; 1617 bio->bi_opf = REQ_OP_READ; 1618 1619 for (j = i; j < num_pages; j++) { 1620 ret = bio_add_page(bio, block_ctx->pagev[j], 1621 PAGE_SIZE, 0); 1622 if (PAGE_SIZE != ret) 1623 break; 1624 } 1625 if (j == i) { 1626 pr_info("btrfsic: error, failed to add a single page!\n"); 1627 return -1; 1628 } 1629 if (submit_bio_wait(bio)) { 1630 pr_info("btrfsic: read error at logical %llu dev %s!\n", 1631 block_ctx->start, block_ctx->dev->name); 1632 bio_put(bio); 1633 return -1; 1634 } 1635 bio_put(bio); 1636 dev_bytenr += (j - i) * PAGE_SIZE; 1637 i = j; 1638 } 1639 for (i = 0; i < num_pages; i++) 1640 block_ctx->datav[i] = kmap(block_ctx->pagev[i]); 1641 1642 return block_ctx->len; 1643 } 1644 1645 static void btrfsic_dump_database(struct btrfsic_state *state) 1646 { 1647 const struct btrfsic_block *b_all; 1648 1649 BUG_ON(NULL == state); 1650 1651 pr_info("all_blocks_list:\n"); 1652 list_for_each_entry(b_all, &state->all_blocks_list, all_blocks_node) { 1653 const struct btrfsic_block_link *l; 1654 1655 pr_info("%c-block @%llu (%s/%llu/%d)\n", 1656 btrfsic_get_block_type(state, b_all), 1657 b_all->logical_bytenr, b_all->dev_state->name, 1658 b_all->dev_bytenr, b_all->mirror_num); 1659 1660 list_for_each_entry(l, &b_all->ref_to_list, node_ref_to) { 1661 pr_info(" %c @%llu (%s/%llu/%d) refers %u* to %c @%llu (%s/%llu/%d)\n", 1662 btrfsic_get_block_type(state, b_all), 1663 b_all->logical_bytenr, b_all->dev_state->name, 1664 b_all->dev_bytenr, b_all->mirror_num, 1665 l->ref_cnt, 1666 btrfsic_get_block_type(state, l->block_ref_to), 1667 l->block_ref_to->logical_bytenr, 1668 l->block_ref_to->dev_state->name, 1669 l->block_ref_to->dev_bytenr, 1670 l->block_ref_to->mirror_num); 1671 } 1672 1673 list_for_each_entry(l, &b_all->ref_from_list, node_ref_from) { 1674 pr_info(" %c @%llu (%s/%llu/%d) is ref %u* from %c @%llu (%s/%llu/%d)\n", 1675 btrfsic_get_block_type(state, b_all), 1676 b_all->logical_bytenr, b_all->dev_state->name, 1677 b_all->dev_bytenr, b_all->mirror_num, 1678 l->ref_cnt, 1679 btrfsic_get_block_type(state, l->block_ref_from), 1680 l->block_ref_from->logical_bytenr, 1681 l->block_ref_from->dev_state->name, 1682 l->block_ref_from->dev_bytenr, 1683 l->block_ref_from->mirror_num); 1684 } 1685 1686 pr_info("\n"); 1687 } 1688 } 1689 1690 /* 1691 * Test whether the disk block contains a tree block (leaf or node) 1692 * (note that this test fails for the super block) 1693 */ 1694 static noinline_for_stack int btrfsic_test_for_metadata( 1695 struct btrfsic_state *state, 1696 char **datav, unsigned int num_pages) 1697 { 1698 struct btrfs_fs_info *fs_info = state->fs_info; 1699 SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); 1700 struct btrfs_header *h; 1701 u8 csum[BTRFS_CSUM_SIZE]; 1702 unsigned int i; 1703 1704 if (num_pages * PAGE_SIZE < state->metablock_size) 1705 return 1; /* not metadata */ 1706 num_pages = state->metablock_size >> PAGE_SHIFT; 1707 h = (struct btrfs_header *)datav[0]; 1708 1709 if (memcmp(h->fsid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE)) 1710 return 1; 1711 1712 shash->tfm = fs_info->csum_shash; 1713 crypto_shash_init(shash); 1714 1715 for (i = 0; i < num_pages; i++) { 1716 u8 *data = i ? datav[i] : (datav[i] + BTRFS_CSUM_SIZE); 1717 size_t sublen = i ? PAGE_SIZE : 1718 (PAGE_SIZE - BTRFS_CSUM_SIZE); 1719 1720 crypto_shash_update(shash, data, sublen); 1721 } 1722 crypto_shash_final(shash, csum); 1723 if (memcmp(csum, h->csum, fs_info->csum_size)) 1724 return 1; 1725 1726 return 0; /* is metadata */ 1727 } 1728 1729 static void btrfsic_process_written_block(struct btrfsic_dev_state *dev_state, 1730 u64 dev_bytenr, char **mapped_datav, 1731 unsigned int num_pages, 1732 struct bio *bio, int *bio_is_patched, 1733 int submit_bio_bh_rw) 1734 { 1735 int is_metadata; 1736 struct btrfsic_block *block; 1737 struct btrfsic_block_data_ctx block_ctx; 1738 int ret; 1739 struct btrfsic_state *state = dev_state->state; 1740 struct block_device *bdev = dev_state->bdev; 1741 unsigned int processed_len; 1742 1743 if (NULL != bio_is_patched) 1744 *bio_is_patched = 0; 1745 1746 again: 1747 if (num_pages == 0) 1748 return; 1749 1750 processed_len = 0; 1751 is_metadata = (0 == btrfsic_test_for_metadata(state, mapped_datav, 1752 num_pages)); 1753 1754 block = btrfsic_block_hashtable_lookup(bdev, dev_bytenr, 1755 &state->block_hashtable); 1756 if (NULL != block) { 1757 u64 bytenr = 0; 1758 struct btrfsic_block_link *l, *tmp; 1759 1760 if (block->is_superblock) { 1761 bytenr = btrfs_super_bytenr((struct btrfs_super_block *) 1762 mapped_datav[0]); 1763 if (num_pages * PAGE_SIZE < 1764 BTRFS_SUPER_INFO_SIZE) { 1765 pr_info("btrfsic: cannot work with too short bios!\n"); 1766 return; 1767 } 1768 is_metadata = 1; 1769 BUG_ON(!PAGE_ALIGNED(BTRFS_SUPER_INFO_SIZE)); 1770 processed_len = BTRFS_SUPER_INFO_SIZE; 1771 if (state->print_mask & 1772 BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE) { 1773 pr_info("[before new superblock is written]:\n"); 1774 btrfsic_dump_tree_sub(state, block, 0); 1775 } 1776 } 1777 if (is_metadata) { 1778 if (!block->is_superblock) { 1779 if (num_pages * PAGE_SIZE < 1780 state->metablock_size) { 1781 pr_info("btrfsic: cannot work with too short bios!\n"); 1782 return; 1783 } 1784 processed_len = state->metablock_size; 1785 bytenr = btrfs_stack_header_bytenr( 1786 (struct btrfs_header *) 1787 mapped_datav[0]); 1788 btrfsic_cmp_log_and_dev_bytenr(state, bytenr, 1789 dev_state, 1790 dev_bytenr); 1791 } 1792 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) { 1793 if (block->logical_bytenr != bytenr && 1794 !(!block->is_metadata && 1795 block->logical_bytenr == 0)) 1796 pr_info("Written block @%llu (%s/%llu/%d) found in hash table, %c, bytenr mismatch (!= stored %llu).\n", 1797 bytenr, dev_state->name, 1798 dev_bytenr, 1799 block->mirror_num, 1800 btrfsic_get_block_type(state, 1801 block), 1802 block->logical_bytenr); 1803 else 1804 pr_info("Written block @%llu (%s/%llu/%d) found in hash table, %c.\n", 1805 bytenr, dev_state->name, 1806 dev_bytenr, block->mirror_num, 1807 btrfsic_get_block_type(state, 1808 block)); 1809 } 1810 block->logical_bytenr = bytenr; 1811 } else { 1812 if (num_pages * PAGE_SIZE < 1813 state->datablock_size) { 1814 pr_info("btrfsic: cannot work with too short bios!\n"); 1815 return; 1816 } 1817 processed_len = state->datablock_size; 1818 bytenr = block->logical_bytenr; 1819 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1820 pr_info("Written block @%llu (%s/%llu/%d) found in hash table, %c.\n", 1821 bytenr, dev_state->name, dev_bytenr, 1822 block->mirror_num, 1823 btrfsic_get_block_type(state, block)); 1824 } 1825 1826 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1827 pr_info("ref_to_list: %cE, ref_from_list: %cE\n", 1828 list_empty(&block->ref_to_list) ? ' ' : '!', 1829 list_empty(&block->ref_from_list) ? ' ' : '!'); 1830 if (btrfsic_is_block_ref_by_superblock(state, block, 0)) { 1831 pr_info("btrfs: attempt to overwrite %c-block @%llu (%s/%llu/%d), old(gen=%llu, objectid=%llu, type=%d, offset=%llu), new(gen=%llu), which is referenced by most recent superblock (superblockgen=%llu)!\n", 1832 btrfsic_get_block_type(state, block), bytenr, 1833 dev_state->name, dev_bytenr, block->mirror_num, 1834 block->generation, 1835 btrfs_disk_key_objectid(&block->disk_key), 1836 block->disk_key.type, 1837 btrfs_disk_key_offset(&block->disk_key), 1838 btrfs_stack_header_generation( 1839 (struct btrfs_header *) mapped_datav[0]), 1840 state->max_superblock_generation); 1841 btrfsic_dump_tree(state); 1842 } 1843 1844 if (!block->is_iodone && !block->never_written) { 1845 pr_info("btrfs: attempt to overwrite %c-block @%llu (%s/%llu/%d), oldgen=%llu, newgen=%llu, which is not yet iodone!\n", 1846 btrfsic_get_block_type(state, block), bytenr, 1847 dev_state->name, dev_bytenr, block->mirror_num, 1848 block->generation, 1849 btrfs_stack_header_generation( 1850 (struct btrfs_header *) 1851 mapped_datav[0])); 1852 /* it would not be safe to go on */ 1853 btrfsic_dump_tree(state); 1854 goto continue_loop; 1855 } 1856 1857 /* 1858 * Clear all references of this block. Do not free 1859 * the block itself even if is not referenced anymore 1860 * because it still carries valuable information 1861 * like whether it was ever written and IO completed. 1862 */ 1863 list_for_each_entry_safe(l, tmp, &block->ref_to_list, 1864 node_ref_to) { 1865 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1866 btrfsic_print_rem_link(state, l); 1867 l->ref_cnt--; 1868 if (0 == l->ref_cnt) { 1869 list_del(&l->node_ref_to); 1870 list_del(&l->node_ref_from); 1871 btrfsic_block_link_hashtable_remove(l); 1872 btrfsic_block_link_free(l); 1873 } 1874 } 1875 1876 block_ctx.dev = dev_state; 1877 block_ctx.dev_bytenr = dev_bytenr; 1878 block_ctx.start = bytenr; 1879 block_ctx.len = processed_len; 1880 block_ctx.pagev = NULL; 1881 block_ctx.mem_to_free = NULL; 1882 block_ctx.datav = mapped_datav; 1883 1884 if (is_metadata || state->include_extent_data) { 1885 block->never_written = 0; 1886 block->iodone_w_error = 0; 1887 if (NULL != bio) { 1888 block->is_iodone = 0; 1889 BUG_ON(NULL == bio_is_patched); 1890 if (!*bio_is_patched) { 1891 block->orig_bio_private = 1892 bio->bi_private; 1893 block->orig_bio_end_io = 1894 bio->bi_end_io; 1895 block->next_in_same_bio = NULL; 1896 bio->bi_private = block; 1897 bio->bi_end_io = btrfsic_bio_end_io; 1898 *bio_is_patched = 1; 1899 } else { 1900 struct btrfsic_block *chained_block = 1901 (struct btrfsic_block *) 1902 bio->bi_private; 1903 1904 BUG_ON(NULL == chained_block); 1905 block->orig_bio_private = 1906 chained_block->orig_bio_private; 1907 block->orig_bio_end_io = 1908 chained_block->orig_bio_end_io; 1909 block->next_in_same_bio = chained_block; 1910 bio->bi_private = block; 1911 } 1912 } else { 1913 block->is_iodone = 1; 1914 block->orig_bio_private = NULL; 1915 block->orig_bio_end_io = NULL; 1916 block->next_in_same_bio = NULL; 1917 } 1918 } 1919 1920 block->flush_gen = dev_state->last_flush_gen + 1; 1921 block->submit_bio_bh_rw = submit_bio_bh_rw; 1922 if (is_metadata) { 1923 block->logical_bytenr = bytenr; 1924 block->is_metadata = 1; 1925 if (block->is_superblock) { 1926 BUG_ON(PAGE_SIZE != 1927 BTRFS_SUPER_INFO_SIZE); 1928 ret = btrfsic_process_written_superblock( 1929 state, 1930 block, 1931 (struct btrfs_super_block *) 1932 mapped_datav[0]); 1933 if (state->print_mask & 1934 BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE) { 1935 pr_info("[after new superblock is written]:\n"); 1936 btrfsic_dump_tree_sub(state, block, 0); 1937 } 1938 } else { 1939 block->mirror_num = 0; /* unknown */ 1940 ret = btrfsic_process_metablock( 1941 state, 1942 block, 1943 &block_ctx, 1944 0, 0); 1945 } 1946 if (ret) 1947 pr_info("btrfsic: btrfsic_process_metablock(root @%llu) failed!\n", 1948 dev_bytenr); 1949 } else { 1950 block->is_metadata = 0; 1951 block->mirror_num = 0; /* unknown */ 1952 block->generation = BTRFSIC_GENERATION_UNKNOWN; 1953 if (!state->include_extent_data 1954 && list_empty(&block->ref_from_list)) { 1955 /* 1956 * disk block is overwritten with extent 1957 * data (not meta data) and we are configured 1958 * to not include extent data: take the 1959 * chance and free the block's memory 1960 */ 1961 btrfsic_block_hashtable_remove(block); 1962 list_del(&block->all_blocks_node); 1963 btrfsic_block_free(block); 1964 } 1965 } 1966 btrfsic_release_block_ctx(&block_ctx); 1967 } else { 1968 /* block has not been found in hash table */ 1969 u64 bytenr; 1970 1971 if (!is_metadata) { 1972 processed_len = state->datablock_size; 1973 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1974 pr_info("Written block (%s/%llu/?) !found in hash table, D.\n", 1975 dev_state->name, dev_bytenr); 1976 if (!state->include_extent_data) { 1977 /* ignore that written D block */ 1978 goto continue_loop; 1979 } 1980 1981 /* this is getting ugly for the 1982 * include_extent_data case... */ 1983 bytenr = 0; /* unknown */ 1984 } else { 1985 processed_len = state->metablock_size; 1986 bytenr = btrfs_stack_header_bytenr( 1987 (struct btrfs_header *) 1988 mapped_datav[0]); 1989 btrfsic_cmp_log_and_dev_bytenr(state, bytenr, dev_state, 1990 dev_bytenr); 1991 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1992 pr_info("Written block @%llu (%s/%llu/?) !found in hash table, M.\n", 1993 bytenr, dev_state->name, dev_bytenr); 1994 } 1995 1996 block_ctx.dev = dev_state; 1997 block_ctx.dev_bytenr = dev_bytenr; 1998 block_ctx.start = bytenr; 1999 block_ctx.len = processed_len; 2000 block_ctx.pagev = NULL; 2001 block_ctx.mem_to_free = NULL; 2002 block_ctx.datav = mapped_datav; 2003 2004 block = btrfsic_block_alloc(); 2005 if (NULL == block) { 2006 btrfsic_release_block_ctx(&block_ctx); 2007 goto continue_loop; 2008 } 2009 block->dev_state = dev_state; 2010 block->dev_bytenr = dev_bytenr; 2011 block->logical_bytenr = bytenr; 2012 block->is_metadata = is_metadata; 2013 block->never_written = 0; 2014 block->iodone_w_error = 0; 2015 block->mirror_num = 0; /* unknown */ 2016 block->flush_gen = dev_state->last_flush_gen + 1; 2017 block->submit_bio_bh_rw = submit_bio_bh_rw; 2018 if (NULL != bio) { 2019 block->is_iodone = 0; 2020 BUG_ON(NULL == bio_is_patched); 2021 if (!*bio_is_patched) { 2022 block->orig_bio_private = bio->bi_private; 2023 block->orig_bio_end_io = bio->bi_end_io; 2024 block->next_in_same_bio = NULL; 2025 bio->bi_private = block; 2026 bio->bi_end_io = btrfsic_bio_end_io; 2027 *bio_is_patched = 1; 2028 } else { 2029 struct btrfsic_block *chained_block = 2030 (struct btrfsic_block *) 2031 bio->bi_private; 2032 2033 BUG_ON(NULL == chained_block); 2034 block->orig_bio_private = 2035 chained_block->orig_bio_private; 2036 block->orig_bio_end_io = 2037 chained_block->orig_bio_end_io; 2038 block->next_in_same_bio = chained_block; 2039 bio->bi_private = block; 2040 } 2041 } else { 2042 block->is_iodone = 1; 2043 block->orig_bio_private = NULL; 2044 block->orig_bio_end_io = NULL; 2045 block->next_in_same_bio = NULL; 2046 } 2047 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2048 pr_info("New written %c-block @%llu (%s/%llu/%d)\n", 2049 is_metadata ? 'M' : 'D', 2050 block->logical_bytenr, block->dev_state->name, 2051 block->dev_bytenr, block->mirror_num); 2052 list_add(&block->all_blocks_node, &state->all_blocks_list); 2053 btrfsic_block_hashtable_add(block, &state->block_hashtable); 2054 2055 if (is_metadata) { 2056 ret = btrfsic_process_metablock(state, block, 2057 &block_ctx, 0, 0); 2058 if (ret) 2059 pr_info("btrfsic: process_metablock(root @%llu) failed!\n", 2060 dev_bytenr); 2061 } 2062 btrfsic_release_block_ctx(&block_ctx); 2063 } 2064 2065 continue_loop: 2066 BUG_ON(!processed_len); 2067 dev_bytenr += processed_len; 2068 mapped_datav += processed_len >> PAGE_SHIFT; 2069 num_pages -= processed_len >> PAGE_SHIFT; 2070 goto again; 2071 } 2072 2073 static void btrfsic_bio_end_io(struct bio *bp) 2074 { 2075 struct btrfsic_block *block = (struct btrfsic_block *)bp->bi_private; 2076 int iodone_w_error; 2077 2078 /* mutex is not held! This is not save if IO is not yet completed 2079 * on umount */ 2080 iodone_w_error = 0; 2081 if (bp->bi_status) 2082 iodone_w_error = 1; 2083 2084 BUG_ON(NULL == block); 2085 bp->bi_private = block->orig_bio_private; 2086 bp->bi_end_io = block->orig_bio_end_io; 2087 2088 do { 2089 struct btrfsic_block *next_block; 2090 struct btrfsic_dev_state *const dev_state = block->dev_state; 2091 2092 if ((dev_state->state->print_mask & 2093 BTRFSIC_PRINT_MASK_END_IO_BIO_BH)) 2094 pr_info("bio_end_io(err=%d) for %c @%llu (%s/%llu/%d)\n", 2095 bp->bi_status, 2096 btrfsic_get_block_type(dev_state->state, block), 2097 block->logical_bytenr, dev_state->name, 2098 block->dev_bytenr, block->mirror_num); 2099 next_block = block->next_in_same_bio; 2100 block->iodone_w_error = iodone_w_error; 2101 if (block->submit_bio_bh_rw & REQ_PREFLUSH) { 2102 dev_state->last_flush_gen++; 2103 if ((dev_state->state->print_mask & 2104 BTRFSIC_PRINT_MASK_END_IO_BIO_BH)) 2105 pr_info("bio_end_io() new %s flush_gen=%llu\n", 2106 dev_state->name, 2107 dev_state->last_flush_gen); 2108 } 2109 if (block->submit_bio_bh_rw & REQ_FUA) 2110 block->flush_gen = 0; /* FUA completed means block is 2111 * on disk */ 2112 block->is_iodone = 1; /* for FLUSH, this releases the block */ 2113 block = next_block; 2114 } while (NULL != block); 2115 2116 bp->bi_end_io(bp); 2117 } 2118 2119 static int btrfsic_process_written_superblock( 2120 struct btrfsic_state *state, 2121 struct btrfsic_block *const superblock, 2122 struct btrfs_super_block *const super_hdr) 2123 { 2124 struct btrfs_fs_info *fs_info = state->fs_info; 2125 int pass; 2126 2127 superblock->generation = btrfs_super_generation(super_hdr); 2128 if (!(superblock->generation > state->max_superblock_generation || 2129 0 == state->max_superblock_generation)) { 2130 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE) 2131 pr_info("btrfsic: superblock @%llu (%s/%llu/%d) with old gen %llu <= %llu\n", 2132 superblock->logical_bytenr, 2133 superblock->dev_state->name, 2134 superblock->dev_bytenr, superblock->mirror_num, 2135 btrfs_super_generation(super_hdr), 2136 state->max_superblock_generation); 2137 } else { 2138 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE) 2139 pr_info("btrfsic: got new superblock @%llu (%s/%llu/%d) with new gen %llu > %llu\n", 2140 superblock->logical_bytenr, 2141 superblock->dev_state->name, 2142 superblock->dev_bytenr, superblock->mirror_num, 2143 btrfs_super_generation(super_hdr), 2144 state->max_superblock_generation); 2145 2146 state->max_superblock_generation = 2147 btrfs_super_generation(super_hdr); 2148 state->latest_superblock = superblock; 2149 } 2150 2151 for (pass = 0; pass < 3; pass++) { 2152 int ret; 2153 u64 next_bytenr; 2154 struct btrfsic_block *next_block; 2155 struct btrfsic_block_data_ctx tmp_next_block_ctx; 2156 struct btrfsic_block_link *l; 2157 int num_copies; 2158 int mirror_num; 2159 const char *additional_string = NULL; 2160 struct btrfs_disk_key tmp_disk_key = {0}; 2161 2162 btrfs_set_disk_key_objectid(&tmp_disk_key, 2163 BTRFS_ROOT_ITEM_KEY); 2164 btrfs_set_disk_key_objectid(&tmp_disk_key, 0); 2165 2166 switch (pass) { 2167 case 0: 2168 btrfs_set_disk_key_objectid(&tmp_disk_key, 2169 BTRFS_ROOT_TREE_OBJECTID); 2170 additional_string = "root "; 2171 next_bytenr = btrfs_super_root(super_hdr); 2172 if (state->print_mask & 2173 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 2174 pr_info("root@%llu\n", next_bytenr); 2175 break; 2176 case 1: 2177 btrfs_set_disk_key_objectid(&tmp_disk_key, 2178 BTRFS_CHUNK_TREE_OBJECTID); 2179 additional_string = "chunk "; 2180 next_bytenr = btrfs_super_chunk_root(super_hdr); 2181 if (state->print_mask & 2182 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 2183 pr_info("chunk@%llu\n", next_bytenr); 2184 break; 2185 case 2: 2186 btrfs_set_disk_key_objectid(&tmp_disk_key, 2187 BTRFS_TREE_LOG_OBJECTID); 2188 additional_string = "log "; 2189 next_bytenr = btrfs_super_log_root(super_hdr); 2190 if (0 == next_bytenr) 2191 continue; 2192 if (state->print_mask & 2193 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 2194 pr_info("log@%llu\n", next_bytenr); 2195 break; 2196 } 2197 2198 num_copies = btrfs_num_copies(fs_info, next_bytenr, 2199 BTRFS_SUPER_INFO_SIZE); 2200 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 2201 pr_info("num_copies(log_bytenr=%llu) = %d\n", 2202 next_bytenr, num_copies); 2203 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 2204 int was_created; 2205 2206 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2207 pr_info("btrfsic_process_written_superblock(mirror_num=%d)\n", mirror_num); 2208 ret = btrfsic_map_block(state, next_bytenr, 2209 BTRFS_SUPER_INFO_SIZE, 2210 &tmp_next_block_ctx, 2211 mirror_num); 2212 if (ret) { 2213 pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n", 2214 next_bytenr, mirror_num); 2215 return -1; 2216 } 2217 2218 next_block = btrfsic_block_lookup_or_add( 2219 state, 2220 &tmp_next_block_ctx, 2221 additional_string, 2222 1, 0, 1, 2223 mirror_num, 2224 &was_created); 2225 if (NULL == next_block) { 2226 btrfsic_release_block_ctx(&tmp_next_block_ctx); 2227 return -1; 2228 } 2229 2230 next_block->disk_key = tmp_disk_key; 2231 if (was_created) 2232 next_block->generation = 2233 BTRFSIC_GENERATION_UNKNOWN; 2234 l = btrfsic_block_link_lookup_or_add( 2235 state, 2236 &tmp_next_block_ctx, 2237 next_block, 2238 superblock, 2239 BTRFSIC_GENERATION_UNKNOWN); 2240 btrfsic_release_block_ctx(&tmp_next_block_ctx); 2241 if (NULL == l) 2242 return -1; 2243 } 2244 } 2245 2246 if (WARN_ON(-1 == btrfsic_check_all_ref_blocks(state, superblock, 0))) 2247 btrfsic_dump_tree(state); 2248 2249 return 0; 2250 } 2251 2252 static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state, 2253 struct btrfsic_block *const block, 2254 int recursion_level) 2255 { 2256 const struct btrfsic_block_link *l; 2257 int ret = 0; 2258 2259 if (recursion_level >= 3 + BTRFS_MAX_LEVEL) { 2260 /* 2261 * Note that this situation can happen and does not 2262 * indicate an error in regular cases. It happens 2263 * when disk blocks are freed and later reused. 2264 * The check-integrity module is not aware of any 2265 * block free operations, it just recognizes block 2266 * write operations. Therefore it keeps the linkage 2267 * information for a block until a block is 2268 * rewritten. This can temporarily cause incorrect 2269 * and even circular linkage information. This 2270 * causes no harm unless such blocks are referenced 2271 * by the most recent super block. 2272 */ 2273 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2274 pr_info("btrfsic: abort cyclic linkage (case 1).\n"); 2275 2276 return ret; 2277 } 2278 2279 /* 2280 * This algorithm is recursive because the amount of used stack 2281 * space is very small and the max recursion depth is limited. 2282 */ 2283 list_for_each_entry(l, &block->ref_to_list, node_ref_to) { 2284 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2285 pr_info("rl=%d, %c @%llu (%s/%llu/%d) %u* refers to %c @%llu (%s/%llu/%d)\n", 2286 recursion_level, 2287 btrfsic_get_block_type(state, block), 2288 block->logical_bytenr, block->dev_state->name, 2289 block->dev_bytenr, block->mirror_num, 2290 l->ref_cnt, 2291 btrfsic_get_block_type(state, l->block_ref_to), 2292 l->block_ref_to->logical_bytenr, 2293 l->block_ref_to->dev_state->name, 2294 l->block_ref_to->dev_bytenr, 2295 l->block_ref_to->mirror_num); 2296 if (l->block_ref_to->never_written) { 2297 pr_info("btrfs: attempt to write superblock which references block %c @%llu (%s/%llu/%d) which is never written!\n", 2298 btrfsic_get_block_type(state, l->block_ref_to), 2299 l->block_ref_to->logical_bytenr, 2300 l->block_ref_to->dev_state->name, 2301 l->block_ref_to->dev_bytenr, 2302 l->block_ref_to->mirror_num); 2303 ret = -1; 2304 } else if (!l->block_ref_to->is_iodone) { 2305 pr_info("btrfs: attempt to write superblock which references block %c @%llu (%s/%llu/%d) which is not yet iodone!\n", 2306 btrfsic_get_block_type(state, l->block_ref_to), 2307 l->block_ref_to->logical_bytenr, 2308 l->block_ref_to->dev_state->name, 2309 l->block_ref_to->dev_bytenr, 2310 l->block_ref_to->mirror_num); 2311 ret = -1; 2312 } else if (l->block_ref_to->iodone_w_error) { 2313 pr_info("btrfs: attempt to write superblock which references block %c @%llu (%s/%llu/%d) which has write error!\n", 2314 btrfsic_get_block_type(state, l->block_ref_to), 2315 l->block_ref_to->logical_bytenr, 2316 l->block_ref_to->dev_state->name, 2317 l->block_ref_to->dev_bytenr, 2318 l->block_ref_to->mirror_num); 2319 ret = -1; 2320 } else if (l->parent_generation != 2321 l->block_ref_to->generation && 2322 BTRFSIC_GENERATION_UNKNOWN != 2323 l->parent_generation && 2324 BTRFSIC_GENERATION_UNKNOWN != 2325 l->block_ref_to->generation) { 2326 pr_info("btrfs: attempt to write superblock which references block %c @%llu (%s/%llu/%d) with generation %llu != parent generation %llu!\n", 2327 btrfsic_get_block_type(state, l->block_ref_to), 2328 l->block_ref_to->logical_bytenr, 2329 l->block_ref_to->dev_state->name, 2330 l->block_ref_to->dev_bytenr, 2331 l->block_ref_to->mirror_num, 2332 l->block_ref_to->generation, 2333 l->parent_generation); 2334 ret = -1; 2335 } else if (l->block_ref_to->flush_gen > 2336 l->block_ref_to->dev_state->last_flush_gen) { 2337 pr_info("btrfs: attempt to write superblock which references block %c @%llu (%s/%llu/%d) which is not flushed out of disk's write cache (block flush_gen=%llu, dev->flush_gen=%llu)!\n", 2338 btrfsic_get_block_type(state, l->block_ref_to), 2339 l->block_ref_to->logical_bytenr, 2340 l->block_ref_to->dev_state->name, 2341 l->block_ref_to->dev_bytenr, 2342 l->block_ref_to->mirror_num, block->flush_gen, 2343 l->block_ref_to->dev_state->last_flush_gen); 2344 ret = -1; 2345 } else if (-1 == btrfsic_check_all_ref_blocks(state, 2346 l->block_ref_to, 2347 recursion_level + 2348 1)) { 2349 ret = -1; 2350 } 2351 } 2352 2353 return ret; 2354 } 2355 2356 static int btrfsic_is_block_ref_by_superblock( 2357 const struct btrfsic_state *state, 2358 const struct btrfsic_block *block, 2359 int recursion_level) 2360 { 2361 const struct btrfsic_block_link *l; 2362 2363 if (recursion_level >= 3 + BTRFS_MAX_LEVEL) { 2364 /* refer to comment at "abort cyclic linkage (case 1)" */ 2365 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2366 pr_info("btrfsic: abort cyclic linkage (case 2).\n"); 2367 2368 return 0; 2369 } 2370 2371 /* 2372 * This algorithm is recursive because the amount of used stack space 2373 * is very small and the max recursion depth is limited. 2374 */ 2375 list_for_each_entry(l, &block->ref_from_list, node_ref_from) { 2376 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2377 pr_info("rl=%d, %c @%llu (%s/%llu/%d) is ref %u* from %c @%llu (%s/%llu/%d)\n", 2378 recursion_level, 2379 btrfsic_get_block_type(state, block), 2380 block->logical_bytenr, block->dev_state->name, 2381 block->dev_bytenr, block->mirror_num, 2382 l->ref_cnt, 2383 btrfsic_get_block_type(state, l->block_ref_from), 2384 l->block_ref_from->logical_bytenr, 2385 l->block_ref_from->dev_state->name, 2386 l->block_ref_from->dev_bytenr, 2387 l->block_ref_from->mirror_num); 2388 if (l->block_ref_from->is_superblock && 2389 state->latest_superblock->dev_bytenr == 2390 l->block_ref_from->dev_bytenr && 2391 state->latest_superblock->dev_state->bdev == 2392 l->block_ref_from->dev_state->bdev) 2393 return 1; 2394 else if (btrfsic_is_block_ref_by_superblock(state, 2395 l->block_ref_from, 2396 recursion_level + 2397 1)) 2398 return 1; 2399 } 2400 2401 return 0; 2402 } 2403 2404 static void btrfsic_print_add_link(const struct btrfsic_state *state, 2405 const struct btrfsic_block_link *l) 2406 { 2407 pr_info("Add %u* link from %c @%llu (%s/%llu/%d) to %c @%llu (%s/%llu/%d).\n", 2408 l->ref_cnt, 2409 btrfsic_get_block_type(state, l->block_ref_from), 2410 l->block_ref_from->logical_bytenr, 2411 l->block_ref_from->dev_state->name, 2412 l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num, 2413 btrfsic_get_block_type(state, l->block_ref_to), 2414 l->block_ref_to->logical_bytenr, 2415 l->block_ref_to->dev_state->name, l->block_ref_to->dev_bytenr, 2416 l->block_ref_to->mirror_num); 2417 } 2418 2419 static void btrfsic_print_rem_link(const struct btrfsic_state *state, 2420 const struct btrfsic_block_link *l) 2421 { 2422 pr_info("Rem %u* link from %c @%llu (%s/%llu/%d) to %c @%llu (%s/%llu/%d).\n", 2423 l->ref_cnt, 2424 btrfsic_get_block_type(state, l->block_ref_from), 2425 l->block_ref_from->logical_bytenr, 2426 l->block_ref_from->dev_state->name, 2427 l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num, 2428 btrfsic_get_block_type(state, l->block_ref_to), 2429 l->block_ref_to->logical_bytenr, 2430 l->block_ref_to->dev_state->name, l->block_ref_to->dev_bytenr, 2431 l->block_ref_to->mirror_num); 2432 } 2433 2434 static char btrfsic_get_block_type(const struct btrfsic_state *state, 2435 const struct btrfsic_block *block) 2436 { 2437 if (block->is_superblock && 2438 state->latest_superblock->dev_bytenr == block->dev_bytenr && 2439 state->latest_superblock->dev_state->bdev == block->dev_state->bdev) 2440 return 'S'; 2441 else if (block->is_superblock) 2442 return 's'; 2443 else if (block->is_metadata) 2444 return 'M'; 2445 else 2446 return 'D'; 2447 } 2448 2449 static void btrfsic_dump_tree(const struct btrfsic_state *state) 2450 { 2451 btrfsic_dump_tree_sub(state, state->latest_superblock, 0); 2452 } 2453 2454 static void btrfsic_dump_tree_sub(const struct btrfsic_state *state, 2455 const struct btrfsic_block *block, 2456 int indent_level) 2457 { 2458 const struct btrfsic_block_link *l; 2459 int indent_add; 2460 static char buf[80]; 2461 int cursor_position; 2462 2463 /* 2464 * Should better fill an on-stack buffer with a complete line and 2465 * dump it at once when it is time to print a newline character. 2466 */ 2467 2468 /* 2469 * This algorithm is recursive because the amount of used stack space 2470 * is very small and the max recursion depth is limited. 2471 */ 2472 indent_add = sprintf(buf, "%c-%llu(%s/%llu/%u)", 2473 btrfsic_get_block_type(state, block), 2474 block->logical_bytenr, block->dev_state->name, 2475 block->dev_bytenr, block->mirror_num); 2476 if (indent_level + indent_add > BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) { 2477 printk("[...]\n"); 2478 return; 2479 } 2480 printk(buf); 2481 indent_level += indent_add; 2482 if (list_empty(&block->ref_to_list)) { 2483 printk("\n"); 2484 return; 2485 } 2486 if (block->mirror_num > 1 && 2487 !(state->print_mask & BTRFSIC_PRINT_MASK_TREE_WITH_ALL_MIRRORS)) { 2488 printk(" [...]\n"); 2489 return; 2490 } 2491 2492 cursor_position = indent_level; 2493 list_for_each_entry(l, &block->ref_to_list, node_ref_to) { 2494 while (cursor_position < indent_level) { 2495 printk(" "); 2496 cursor_position++; 2497 } 2498 if (l->ref_cnt > 1) 2499 indent_add = sprintf(buf, " %d*--> ", l->ref_cnt); 2500 else 2501 indent_add = sprintf(buf, " --> "); 2502 if (indent_level + indent_add > 2503 BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) { 2504 printk("[...]\n"); 2505 cursor_position = 0; 2506 continue; 2507 } 2508 2509 printk(buf); 2510 2511 btrfsic_dump_tree_sub(state, l->block_ref_to, 2512 indent_level + indent_add); 2513 cursor_position = 0; 2514 } 2515 } 2516 2517 static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add( 2518 struct btrfsic_state *state, 2519 struct btrfsic_block_data_ctx *next_block_ctx, 2520 struct btrfsic_block *next_block, 2521 struct btrfsic_block *from_block, 2522 u64 parent_generation) 2523 { 2524 struct btrfsic_block_link *l; 2525 2526 l = btrfsic_block_link_hashtable_lookup(next_block_ctx->dev->bdev, 2527 next_block_ctx->dev_bytenr, 2528 from_block->dev_state->bdev, 2529 from_block->dev_bytenr, 2530 &state->block_link_hashtable); 2531 if (NULL == l) { 2532 l = btrfsic_block_link_alloc(); 2533 if (!l) 2534 return NULL; 2535 2536 l->block_ref_to = next_block; 2537 l->block_ref_from = from_block; 2538 l->ref_cnt = 1; 2539 l->parent_generation = parent_generation; 2540 2541 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2542 btrfsic_print_add_link(state, l); 2543 2544 list_add(&l->node_ref_to, &from_block->ref_to_list); 2545 list_add(&l->node_ref_from, &next_block->ref_from_list); 2546 2547 btrfsic_block_link_hashtable_add(l, 2548 &state->block_link_hashtable); 2549 } else { 2550 l->ref_cnt++; 2551 l->parent_generation = parent_generation; 2552 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2553 btrfsic_print_add_link(state, l); 2554 } 2555 2556 return l; 2557 } 2558 2559 static struct btrfsic_block *btrfsic_block_lookup_or_add( 2560 struct btrfsic_state *state, 2561 struct btrfsic_block_data_ctx *block_ctx, 2562 const char *additional_string, 2563 int is_metadata, 2564 int is_iodone, 2565 int never_written, 2566 int mirror_num, 2567 int *was_created) 2568 { 2569 struct btrfsic_block *block; 2570 2571 block = btrfsic_block_hashtable_lookup(block_ctx->dev->bdev, 2572 block_ctx->dev_bytenr, 2573 &state->block_hashtable); 2574 if (NULL == block) { 2575 struct btrfsic_dev_state *dev_state; 2576 2577 block = btrfsic_block_alloc(); 2578 if (!block) 2579 return NULL; 2580 2581 dev_state = btrfsic_dev_state_lookup(block_ctx->dev->bdev->bd_dev); 2582 if (NULL == dev_state) { 2583 pr_info("btrfsic: error, lookup dev_state failed!\n"); 2584 btrfsic_block_free(block); 2585 return NULL; 2586 } 2587 block->dev_state = dev_state; 2588 block->dev_bytenr = block_ctx->dev_bytenr; 2589 block->logical_bytenr = block_ctx->start; 2590 block->is_metadata = is_metadata; 2591 block->is_iodone = is_iodone; 2592 block->never_written = never_written; 2593 block->mirror_num = mirror_num; 2594 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2595 pr_info("New %s%c-block @%llu (%s/%llu/%d)\n", 2596 additional_string, 2597 btrfsic_get_block_type(state, block), 2598 block->logical_bytenr, dev_state->name, 2599 block->dev_bytenr, mirror_num); 2600 list_add(&block->all_blocks_node, &state->all_blocks_list); 2601 btrfsic_block_hashtable_add(block, &state->block_hashtable); 2602 if (NULL != was_created) 2603 *was_created = 1; 2604 } else { 2605 if (NULL != was_created) 2606 *was_created = 0; 2607 } 2608 2609 return block; 2610 } 2611 2612 static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state, 2613 u64 bytenr, 2614 struct btrfsic_dev_state *dev_state, 2615 u64 dev_bytenr) 2616 { 2617 struct btrfs_fs_info *fs_info = state->fs_info; 2618 struct btrfsic_block_data_ctx block_ctx; 2619 int num_copies; 2620 int mirror_num; 2621 int match = 0; 2622 int ret; 2623 2624 num_copies = btrfs_num_copies(fs_info, bytenr, state->metablock_size); 2625 2626 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 2627 ret = btrfsic_map_block(state, bytenr, state->metablock_size, 2628 &block_ctx, mirror_num); 2629 if (ret) { 2630 pr_info("btrfsic: btrfsic_map_block(logical @%llu, mirror %d) failed!\n", 2631 bytenr, mirror_num); 2632 continue; 2633 } 2634 2635 if (dev_state->bdev == block_ctx.dev->bdev && 2636 dev_bytenr == block_ctx.dev_bytenr) { 2637 match++; 2638 btrfsic_release_block_ctx(&block_ctx); 2639 break; 2640 } 2641 btrfsic_release_block_ctx(&block_ctx); 2642 } 2643 2644 if (WARN_ON(!match)) { 2645 pr_info("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=%s, phys_bytenr=%llu)!\n", 2646 bytenr, dev_state->name, dev_bytenr); 2647 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 2648 ret = btrfsic_map_block(state, bytenr, 2649 state->metablock_size, 2650 &block_ctx, mirror_num); 2651 if (ret) 2652 continue; 2653 2654 pr_info("Read logical bytenr @%llu maps to (%s/%llu/%d)\n", 2655 bytenr, block_ctx.dev->name, 2656 block_ctx.dev_bytenr, mirror_num); 2657 } 2658 } 2659 } 2660 2661 static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev) 2662 { 2663 return btrfsic_dev_state_hashtable_lookup(dev, 2664 &btrfsic_dev_state_hashtable); 2665 } 2666 2667 static void __btrfsic_submit_bio(struct bio *bio) 2668 { 2669 struct btrfsic_dev_state *dev_state; 2670 2671 if (!btrfsic_is_initialized) 2672 return; 2673 2674 mutex_lock(&btrfsic_mutex); 2675 /* since btrfsic_submit_bio() is also called before 2676 * btrfsic_mount(), this might return NULL */ 2677 dev_state = btrfsic_dev_state_lookup(bio_dev(bio) + bio->bi_partno); 2678 if (NULL != dev_state && 2679 (bio_op(bio) == REQ_OP_WRITE) && bio_has_data(bio)) { 2680 unsigned int i = 0; 2681 u64 dev_bytenr; 2682 u64 cur_bytenr; 2683 struct bio_vec bvec; 2684 struct bvec_iter iter; 2685 int bio_is_patched; 2686 char **mapped_datav; 2687 unsigned int segs = bio_segments(bio); 2688 2689 dev_bytenr = 512 * bio->bi_iter.bi_sector; 2690 bio_is_patched = 0; 2691 if (dev_state->state->print_mask & 2692 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH) 2693 pr_info("submit_bio(rw=%d,0x%x, bi_vcnt=%u, bi_sector=%llu (bytenr %llu), bi_disk=%p)\n", 2694 bio_op(bio), bio->bi_opf, segs, 2695 bio->bi_iter.bi_sector, dev_bytenr, bio->bi_disk); 2696 2697 mapped_datav = kmalloc_array(segs, 2698 sizeof(*mapped_datav), GFP_NOFS); 2699 if (!mapped_datav) 2700 goto leave; 2701 cur_bytenr = dev_bytenr; 2702 2703 bio_for_each_segment(bvec, bio, iter) { 2704 BUG_ON(bvec.bv_len != PAGE_SIZE); 2705 mapped_datav[i] = kmap(bvec.bv_page); 2706 i++; 2707 2708 if (dev_state->state->print_mask & 2709 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE) 2710 pr_info("#%u: bytenr=%llu, len=%u, offset=%u\n", 2711 i, cur_bytenr, bvec.bv_len, bvec.bv_offset); 2712 cur_bytenr += bvec.bv_len; 2713 } 2714 btrfsic_process_written_block(dev_state, dev_bytenr, 2715 mapped_datav, segs, 2716 bio, &bio_is_patched, 2717 bio->bi_opf); 2718 bio_for_each_segment(bvec, bio, iter) 2719 kunmap(bvec.bv_page); 2720 kfree(mapped_datav); 2721 } else if (NULL != dev_state && (bio->bi_opf & REQ_PREFLUSH)) { 2722 if (dev_state->state->print_mask & 2723 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH) 2724 pr_info("submit_bio(rw=%d,0x%x FLUSH, disk=%p)\n", 2725 bio_op(bio), bio->bi_opf, bio->bi_disk); 2726 if (!dev_state->dummy_block_for_bio_bh_flush.is_iodone) { 2727 if ((dev_state->state->print_mask & 2728 (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH | 2729 BTRFSIC_PRINT_MASK_VERBOSE))) 2730 pr_info("btrfsic_submit_bio(%s) with FLUSH but dummy block already in use (ignored)!\n", 2731 dev_state->name); 2732 } else { 2733 struct btrfsic_block *const block = 2734 &dev_state->dummy_block_for_bio_bh_flush; 2735 2736 block->is_iodone = 0; 2737 block->never_written = 0; 2738 block->iodone_w_error = 0; 2739 block->flush_gen = dev_state->last_flush_gen + 1; 2740 block->submit_bio_bh_rw = bio->bi_opf; 2741 block->orig_bio_private = bio->bi_private; 2742 block->orig_bio_end_io = bio->bi_end_io; 2743 block->next_in_same_bio = NULL; 2744 bio->bi_private = block; 2745 bio->bi_end_io = btrfsic_bio_end_io; 2746 } 2747 } 2748 leave: 2749 mutex_unlock(&btrfsic_mutex); 2750 } 2751 2752 void btrfsic_submit_bio(struct bio *bio) 2753 { 2754 __btrfsic_submit_bio(bio); 2755 submit_bio(bio); 2756 } 2757 2758 int btrfsic_submit_bio_wait(struct bio *bio) 2759 { 2760 __btrfsic_submit_bio(bio); 2761 return submit_bio_wait(bio); 2762 } 2763 2764 int btrfsic_mount(struct btrfs_fs_info *fs_info, 2765 struct btrfs_fs_devices *fs_devices, 2766 int including_extent_data, u32 print_mask) 2767 { 2768 int ret; 2769 struct btrfsic_state *state; 2770 struct list_head *dev_head = &fs_devices->devices; 2771 struct btrfs_device *device; 2772 2773 if (!PAGE_ALIGNED(fs_info->nodesize)) { 2774 pr_info("btrfsic: cannot handle nodesize %d not being a multiple of PAGE_SIZE %ld!\n", 2775 fs_info->nodesize, PAGE_SIZE); 2776 return -1; 2777 } 2778 if (!PAGE_ALIGNED(fs_info->sectorsize)) { 2779 pr_info("btrfsic: cannot handle sectorsize %d not being a multiple of PAGE_SIZE %ld!\n", 2780 fs_info->sectorsize, PAGE_SIZE); 2781 return -1; 2782 } 2783 state = kvzalloc(sizeof(*state), GFP_KERNEL); 2784 if (!state) 2785 return -ENOMEM; 2786 2787 if (!btrfsic_is_initialized) { 2788 mutex_init(&btrfsic_mutex); 2789 btrfsic_dev_state_hashtable_init(&btrfsic_dev_state_hashtable); 2790 btrfsic_is_initialized = 1; 2791 } 2792 mutex_lock(&btrfsic_mutex); 2793 state->fs_info = fs_info; 2794 state->print_mask = print_mask; 2795 state->include_extent_data = including_extent_data; 2796 state->metablock_size = fs_info->nodesize; 2797 state->datablock_size = fs_info->sectorsize; 2798 INIT_LIST_HEAD(&state->all_blocks_list); 2799 btrfsic_block_hashtable_init(&state->block_hashtable); 2800 btrfsic_block_link_hashtable_init(&state->block_link_hashtable); 2801 state->max_superblock_generation = 0; 2802 state->latest_superblock = NULL; 2803 2804 list_for_each_entry(device, dev_head, dev_list) { 2805 struct btrfsic_dev_state *ds; 2806 const char *p; 2807 2808 if (!device->bdev || !device->name) 2809 continue; 2810 2811 ds = btrfsic_dev_state_alloc(); 2812 if (NULL == ds) { 2813 mutex_unlock(&btrfsic_mutex); 2814 return -ENOMEM; 2815 } 2816 ds->bdev = device->bdev; 2817 ds->state = state; 2818 bdevname(ds->bdev, ds->name); 2819 ds->name[BDEVNAME_SIZE - 1] = '\0'; 2820 p = kbasename(ds->name); 2821 strlcpy(ds->name, p, sizeof(ds->name)); 2822 btrfsic_dev_state_hashtable_add(ds, 2823 &btrfsic_dev_state_hashtable); 2824 } 2825 2826 ret = btrfsic_process_superblock(state, fs_devices); 2827 if (0 != ret) { 2828 mutex_unlock(&btrfsic_mutex); 2829 btrfsic_unmount(fs_devices); 2830 return ret; 2831 } 2832 2833 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_DATABASE) 2834 btrfsic_dump_database(state); 2835 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_TREE) 2836 btrfsic_dump_tree(state); 2837 2838 mutex_unlock(&btrfsic_mutex); 2839 return 0; 2840 } 2841 2842 void btrfsic_unmount(struct btrfs_fs_devices *fs_devices) 2843 { 2844 struct btrfsic_block *b_all, *tmp_all; 2845 struct btrfsic_state *state; 2846 struct list_head *dev_head = &fs_devices->devices; 2847 struct btrfs_device *device; 2848 2849 if (!btrfsic_is_initialized) 2850 return; 2851 2852 mutex_lock(&btrfsic_mutex); 2853 2854 state = NULL; 2855 list_for_each_entry(device, dev_head, dev_list) { 2856 struct btrfsic_dev_state *ds; 2857 2858 if (!device->bdev || !device->name) 2859 continue; 2860 2861 ds = btrfsic_dev_state_hashtable_lookup( 2862 device->bdev->bd_dev, 2863 &btrfsic_dev_state_hashtable); 2864 if (NULL != ds) { 2865 state = ds->state; 2866 btrfsic_dev_state_hashtable_remove(ds); 2867 btrfsic_dev_state_free(ds); 2868 } 2869 } 2870 2871 if (NULL == state) { 2872 pr_info("btrfsic: error, cannot find state information on umount!\n"); 2873 mutex_unlock(&btrfsic_mutex); 2874 return; 2875 } 2876 2877 /* 2878 * Don't care about keeping the lists' state up to date, 2879 * just free all memory that was allocated dynamically. 2880 * Free the blocks and the block_links. 2881 */ 2882 list_for_each_entry_safe(b_all, tmp_all, &state->all_blocks_list, 2883 all_blocks_node) { 2884 struct btrfsic_block_link *l, *tmp; 2885 2886 list_for_each_entry_safe(l, tmp, &b_all->ref_to_list, 2887 node_ref_to) { 2888 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2889 btrfsic_print_rem_link(state, l); 2890 2891 l->ref_cnt--; 2892 if (0 == l->ref_cnt) 2893 btrfsic_block_link_free(l); 2894 } 2895 2896 if (b_all->is_iodone || b_all->never_written) 2897 btrfsic_block_free(b_all); 2898 else 2899 pr_info("btrfs: attempt to free %c-block @%llu (%s/%llu/%d) on umount which is not yet iodone!\n", 2900 btrfsic_get_block_type(state, b_all), 2901 b_all->logical_bytenr, b_all->dev_state->name, 2902 b_all->dev_bytenr, b_all->mirror_num); 2903 } 2904 2905 mutex_unlock(&btrfsic_mutex); 2906 2907 kvfree(state); 2908 } 2909