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 /* Pages must be unmapped in reverse order */ 1559 while (num_pages > 0) { 1560 num_pages--; 1561 if (block_ctx->datav[num_pages]) { 1562 kunmap_local(block_ctx->datav[num_pages]); 1563 block_ctx->datav[num_pages] = NULL; 1564 } 1565 if (block_ctx->pagev[num_pages]) { 1566 __free_page(block_ctx->pagev[num_pages]); 1567 block_ctx->pagev[num_pages] = NULL; 1568 } 1569 } 1570 1571 kfree(block_ctx->mem_to_free); 1572 block_ctx->mem_to_free = NULL; 1573 block_ctx->pagev = NULL; 1574 block_ctx->datav = NULL; 1575 } 1576 } 1577 1578 static int btrfsic_read_block(struct btrfsic_state *state, 1579 struct btrfsic_block_data_ctx *block_ctx) 1580 { 1581 unsigned int num_pages; 1582 unsigned int i; 1583 size_t size; 1584 u64 dev_bytenr; 1585 int ret; 1586 1587 BUG_ON(block_ctx->datav); 1588 BUG_ON(block_ctx->pagev); 1589 BUG_ON(block_ctx->mem_to_free); 1590 if (!PAGE_ALIGNED(block_ctx->dev_bytenr)) { 1591 pr_info("btrfsic: read_block() with unaligned bytenr %llu\n", 1592 block_ctx->dev_bytenr); 1593 return -1; 1594 } 1595 1596 num_pages = (block_ctx->len + (u64)PAGE_SIZE - 1) >> 1597 PAGE_SHIFT; 1598 size = sizeof(*block_ctx->datav) + sizeof(*block_ctx->pagev); 1599 block_ctx->mem_to_free = kcalloc(num_pages, size, GFP_NOFS); 1600 if (!block_ctx->mem_to_free) 1601 return -ENOMEM; 1602 block_ctx->datav = block_ctx->mem_to_free; 1603 block_ctx->pagev = (struct page **)(block_ctx->datav + num_pages); 1604 for (i = 0; i < num_pages; i++) { 1605 block_ctx->pagev[i] = alloc_page(GFP_NOFS); 1606 if (!block_ctx->pagev[i]) 1607 return -1; 1608 } 1609 1610 dev_bytenr = block_ctx->dev_bytenr; 1611 for (i = 0; i < num_pages;) { 1612 struct bio *bio; 1613 unsigned int j; 1614 1615 bio = btrfs_io_bio_alloc(num_pages - i); 1616 bio_set_dev(bio, block_ctx->dev->bdev); 1617 bio->bi_iter.bi_sector = dev_bytenr >> 9; 1618 bio->bi_opf = REQ_OP_READ; 1619 1620 for (j = i; j < num_pages; j++) { 1621 ret = bio_add_page(bio, block_ctx->pagev[j], 1622 PAGE_SIZE, 0); 1623 if (PAGE_SIZE != ret) 1624 break; 1625 } 1626 if (j == i) { 1627 pr_info("btrfsic: error, failed to add a single page!\n"); 1628 return -1; 1629 } 1630 if (submit_bio_wait(bio)) { 1631 pr_info("btrfsic: read error at logical %llu dev %s!\n", 1632 block_ctx->start, block_ctx->dev->name); 1633 bio_put(bio); 1634 return -1; 1635 } 1636 bio_put(bio); 1637 dev_bytenr += (j - i) * PAGE_SIZE; 1638 i = j; 1639 } 1640 for (i = 0; i < num_pages; i++) 1641 block_ctx->datav[i] = kmap_local_page(block_ctx->pagev[i]); 1642 1643 return block_ctx->len; 1644 } 1645 1646 static void btrfsic_dump_database(struct btrfsic_state *state) 1647 { 1648 const struct btrfsic_block *b_all; 1649 1650 BUG_ON(NULL == state); 1651 1652 pr_info("all_blocks_list:\n"); 1653 list_for_each_entry(b_all, &state->all_blocks_list, all_blocks_node) { 1654 const struct btrfsic_block_link *l; 1655 1656 pr_info("%c-block @%llu (%s/%llu/%d)\n", 1657 btrfsic_get_block_type(state, b_all), 1658 b_all->logical_bytenr, b_all->dev_state->name, 1659 b_all->dev_bytenr, b_all->mirror_num); 1660 1661 list_for_each_entry(l, &b_all->ref_to_list, node_ref_to) { 1662 pr_info(" %c @%llu (%s/%llu/%d) refers %u* to %c @%llu (%s/%llu/%d)\n", 1663 btrfsic_get_block_type(state, b_all), 1664 b_all->logical_bytenr, b_all->dev_state->name, 1665 b_all->dev_bytenr, b_all->mirror_num, 1666 l->ref_cnt, 1667 btrfsic_get_block_type(state, l->block_ref_to), 1668 l->block_ref_to->logical_bytenr, 1669 l->block_ref_to->dev_state->name, 1670 l->block_ref_to->dev_bytenr, 1671 l->block_ref_to->mirror_num); 1672 } 1673 1674 list_for_each_entry(l, &b_all->ref_from_list, node_ref_from) { 1675 pr_info(" %c @%llu (%s/%llu/%d) is ref %u* from %c @%llu (%s/%llu/%d)\n", 1676 btrfsic_get_block_type(state, b_all), 1677 b_all->logical_bytenr, b_all->dev_state->name, 1678 b_all->dev_bytenr, b_all->mirror_num, 1679 l->ref_cnt, 1680 btrfsic_get_block_type(state, l->block_ref_from), 1681 l->block_ref_from->logical_bytenr, 1682 l->block_ref_from->dev_state->name, 1683 l->block_ref_from->dev_bytenr, 1684 l->block_ref_from->mirror_num); 1685 } 1686 1687 pr_info("\n"); 1688 } 1689 } 1690 1691 /* 1692 * Test whether the disk block contains a tree block (leaf or node) 1693 * (note that this test fails for the super block) 1694 */ 1695 static noinline_for_stack int btrfsic_test_for_metadata( 1696 struct btrfsic_state *state, 1697 char **datav, unsigned int num_pages) 1698 { 1699 struct btrfs_fs_info *fs_info = state->fs_info; 1700 SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); 1701 struct btrfs_header *h; 1702 u8 csum[BTRFS_CSUM_SIZE]; 1703 unsigned int i; 1704 1705 if (num_pages * PAGE_SIZE < state->metablock_size) 1706 return 1; /* not metadata */ 1707 num_pages = state->metablock_size >> PAGE_SHIFT; 1708 h = (struct btrfs_header *)datav[0]; 1709 1710 if (memcmp(h->fsid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE)) 1711 return 1; 1712 1713 shash->tfm = fs_info->csum_shash; 1714 crypto_shash_init(shash); 1715 1716 for (i = 0; i < num_pages; i++) { 1717 u8 *data = i ? datav[i] : (datav[i] + BTRFS_CSUM_SIZE); 1718 size_t sublen = i ? PAGE_SIZE : 1719 (PAGE_SIZE - BTRFS_CSUM_SIZE); 1720 1721 crypto_shash_update(shash, data, sublen); 1722 } 1723 crypto_shash_final(shash, csum); 1724 if (memcmp(csum, h->csum, fs_info->csum_size)) 1725 return 1; 1726 1727 return 0; /* is metadata */ 1728 } 1729 1730 static void btrfsic_process_written_block(struct btrfsic_dev_state *dev_state, 1731 u64 dev_bytenr, char **mapped_datav, 1732 unsigned int num_pages, 1733 struct bio *bio, int *bio_is_patched, 1734 int submit_bio_bh_rw) 1735 { 1736 int is_metadata; 1737 struct btrfsic_block *block; 1738 struct btrfsic_block_data_ctx block_ctx; 1739 int ret; 1740 struct btrfsic_state *state = dev_state->state; 1741 struct block_device *bdev = dev_state->bdev; 1742 unsigned int processed_len; 1743 1744 if (NULL != bio_is_patched) 1745 *bio_is_patched = 0; 1746 1747 again: 1748 if (num_pages == 0) 1749 return; 1750 1751 processed_len = 0; 1752 is_metadata = (0 == btrfsic_test_for_metadata(state, mapped_datav, 1753 num_pages)); 1754 1755 block = btrfsic_block_hashtable_lookup(bdev, dev_bytenr, 1756 &state->block_hashtable); 1757 if (NULL != block) { 1758 u64 bytenr = 0; 1759 struct btrfsic_block_link *l, *tmp; 1760 1761 if (block->is_superblock) { 1762 bytenr = btrfs_super_bytenr((struct btrfs_super_block *) 1763 mapped_datav[0]); 1764 if (num_pages * PAGE_SIZE < 1765 BTRFS_SUPER_INFO_SIZE) { 1766 pr_info("btrfsic: cannot work with too short bios!\n"); 1767 return; 1768 } 1769 is_metadata = 1; 1770 BUG_ON(!PAGE_ALIGNED(BTRFS_SUPER_INFO_SIZE)); 1771 processed_len = BTRFS_SUPER_INFO_SIZE; 1772 if (state->print_mask & 1773 BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE) { 1774 pr_info("[before new superblock is written]:\n"); 1775 btrfsic_dump_tree_sub(state, block, 0); 1776 } 1777 } 1778 if (is_metadata) { 1779 if (!block->is_superblock) { 1780 if (num_pages * PAGE_SIZE < 1781 state->metablock_size) { 1782 pr_info("btrfsic: cannot work with too short bios!\n"); 1783 return; 1784 } 1785 processed_len = state->metablock_size; 1786 bytenr = btrfs_stack_header_bytenr( 1787 (struct btrfs_header *) 1788 mapped_datav[0]); 1789 btrfsic_cmp_log_and_dev_bytenr(state, bytenr, 1790 dev_state, 1791 dev_bytenr); 1792 } 1793 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) { 1794 if (block->logical_bytenr != bytenr && 1795 !(!block->is_metadata && 1796 block->logical_bytenr == 0)) 1797 pr_info("Written block @%llu (%s/%llu/%d) found in hash table, %c, bytenr mismatch (!= stored %llu).\n", 1798 bytenr, dev_state->name, 1799 dev_bytenr, 1800 block->mirror_num, 1801 btrfsic_get_block_type(state, 1802 block), 1803 block->logical_bytenr); 1804 else 1805 pr_info("Written block @%llu (%s/%llu/%d) found in hash table, %c.\n", 1806 bytenr, dev_state->name, 1807 dev_bytenr, block->mirror_num, 1808 btrfsic_get_block_type(state, 1809 block)); 1810 } 1811 block->logical_bytenr = bytenr; 1812 } else { 1813 if (num_pages * PAGE_SIZE < 1814 state->datablock_size) { 1815 pr_info("btrfsic: cannot work with too short bios!\n"); 1816 return; 1817 } 1818 processed_len = state->datablock_size; 1819 bytenr = block->logical_bytenr; 1820 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1821 pr_info("Written block @%llu (%s/%llu/%d) found in hash table, %c.\n", 1822 bytenr, dev_state->name, dev_bytenr, 1823 block->mirror_num, 1824 btrfsic_get_block_type(state, block)); 1825 } 1826 1827 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1828 pr_info("ref_to_list: %cE, ref_from_list: %cE\n", 1829 list_empty(&block->ref_to_list) ? ' ' : '!', 1830 list_empty(&block->ref_from_list) ? ' ' : '!'); 1831 if (btrfsic_is_block_ref_by_superblock(state, block, 0)) { 1832 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", 1833 btrfsic_get_block_type(state, block), bytenr, 1834 dev_state->name, dev_bytenr, block->mirror_num, 1835 block->generation, 1836 btrfs_disk_key_objectid(&block->disk_key), 1837 block->disk_key.type, 1838 btrfs_disk_key_offset(&block->disk_key), 1839 btrfs_stack_header_generation( 1840 (struct btrfs_header *) mapped_datav[0]), 1841 state->max_superblock_generation); 1842 btrfsic_dump_tree(state); 1843 } 1844 1845 if (!block->is_iodone && !block->never_written) { 1846 pr_info("btrfs: attempt to overwrite %c-block @%llu (%s/%llu/%d), oldgen=%llu, newgen=%llu, which is not yet iodone!\n", 1847 btrfsic_get_block_type(state, block), bytenr, 1848 dev_state->name, dev_bytenr, block->mirror_num, 1849 block->generation, 1850 btrfs_stack_header_generation( 1851 (struct btrfs_header *) 1852 mapped_datav[0])); 1853 /* it would not be safe to go on */ 1854 btrfsic_dump_tree(state); 1855 goto continue_loop; 1856 } 1857 1858 /* 1859 * Clear all references of this block. Do not free 1860 * the block itself even if is not referenced anymore 1861 * because it still carries valuable information 1862 * like whether it was ever written and IO completed. 1863 */ 1864 list_for_each_entry_safe(l, tmp, &block->ref_to_list, 1865 node_ref_to) { 1866 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1867 btrfsic_print_rem_link(state, l); 1868 l->ref_cnt--; 1869 if (0 == l->ref_cnt) { 1870 list_del(&l->node_ref_to); 1871 list_del(&l->node_ref_from); 1872 btrfsic_block_link_hashtable_remove(l); 1873 btrfsic_block_link_free(l); 1874 } 1875 } 1876 1877 block_ctx.dev = dev_state; 1878 block_ctx.dev_bytenr = dev_bytenr; 1879 block_ctx.start = bytenr; 1880 block_ctx.len = processed_len; 1881 block_ctx.pagev = NULL; 1882 block_ctx.mem_to_free = NULL; 1883 block_ctx.datav = mapped_datav; 1884 1885 if (is_metadata || state->include_extent_data) { 1886 block->never_written = 0; 1887 block->iodone_w_error = 0; 1888 if (NULL != bio) { 1889 block->is_iodone = 0; 1890 BUG_ON(NULL == bio_is_patched); 1891 if (!*bio_is_patched) { 1892 block->orig_bio_private = 1893 bio->bi_private; 1894 block->orig_bio_end_io = 1895 bio->bi_end_io; 1896 block->next_in_same_bio = NULL; 1897 bio->bi_private = block; 1898 bio->bi_end_io = btrfsic_bio_end_io; 1899 *bio_is_patched = 1; 1900 } else { 1901 struct btrfsic_block *chained_block = 1902 (struct btrfsic_block *) 1903 bio->bi_private; 1904 1905 BUG_ON(NULL == chained_block); 1906 block->orig_bio_private = 1907 chained_block->orig_bio_private; 1908 block->orig_bio_end_io = 1909 chained_block->orig_bio_end_io; 1910 block->next_in_same_bio = chained_block; 1911 bio->bi_private = block; 1912 } 1913 } else { 1914 block->is_iodone = 1; 1915 block->orig_bio_private = NULL; 1916 block->orig_bio_end_io = NULL; 1917 block->next_in_same_bio = NULL; 1918 } 1919 } 1920 1921 block->flush_gen = dev_state->last_flush_gen + 1; 1922 block->submit_bio_bh_rw = submit_bio_bh_rw; 1923 if (is_metadata) { 1924 block->logical_bytenr = bytenr; 1925 block->is_metadata = 1; 1926 if (block->is_superblock) { 1927 BUG_ON(PAGE_SIZE != 1928 BTRFS_SUPER_INFO_SIZE); 1929 ret = btrfsic_process_written_superblock( 1930 state, 1931 block, 1932 (struct btrfs_super_block *) 1933 mapped_datav[0]); 1934 if (state->print_mask & 1935 BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE) { 1936 pr_info("[after new superblock is written]:\n"); 1937 btrfsic_dump_tree_sub(state, block, 0); 1938 } 1939 } else { 1940 block->mirror_num = 0; /* unknown */ 1941 ret = btrfsic_process_metablock( 1942 state, 1943 block, 1944 &block_ctx, 1945 0, 0); 1946 } 1947 if (ret) 1948 pr_info("btrfsic: btrfsic_process_metablock(root @%llu) failed!\n", 1949 dev_bytenr); 1950 } else { 1951 block->is_metadata = 0; 1952 block->mirror_num = 0; /* unknown */ 1953 block->generation = BTRFSIC_GENERATION_UNKNOWN; 1954 if (!state->include_extent_data 1955 && list_empty(&block->ref_from_list)) { 1956 /* 1957 * disk block is overwritten with extent 1958 * data (not meta data) and we are configured 1959 * to not include extent data: take the 1960 * chance and free the block's memory 1961 */ 1962 btrfsic_block_hashtable_remove(block); 1963 list_del(&block->all_blocks_node); 1964 btrfsic_block_free(block); 1965 } 1966 } 1967 btrfsic_release_block_ctx(&block_ctx); 1968 } else { 1969 /* block has not been found in hash table */ 1970 u64 bytenr; 1971 1972 if (!is_metadata) { 1973 processed_len = state->datablock_size; 1974 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1975 pr_info("Written block (%s/%llu/?) !found in hash table, D.\n", 1976 dev_state->name, dev_bytenr); 1977 if (!state->include_extent_data) { 1978 /* ignore that written D block */ 1979 goto continue_loop; 1980 } 1981 1982 /* this is getting ugly for the 1983 * include_extent_data case... */ 1984 bytenr = 0; /* unknown */ 1985 } else { 1986 processed_len = state->metablock_size; 1987 bytenr = btrfs_stack_header_bytenr( 1988 (struct btrfs_header *) 1989 mapped_datav[0]); 1990 btrfsic_cmp_log_and_dev_bytenr(state, bytenr, dev_state, 1991 dev_bytenr); 1992 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 1993 pr_info("Written block @%llu (%s/%llu/?) !found in hash table, M.\n", 1994 bytenr, dev_state->name, dev_bytenr); 1995 } 1996 1997 block_ctx.dev = dev_state; 1998 block_ctx.dev_bytenr = dev_bytenr; 1999 block_ctx.start = bytenr; 2000 block_ctx.len = processed_len; 2001 block_ctx.pagev = NULL; 2002 block_ctx.mem_to_free = NULL; 2003 block_ctx.datav = mapped_datav; 2004 2005 block = btrfsic_block_alloc(); 2006 if (NULL == block) { 2007 btrfsic_release_block_ctx(&block_ctx); 2008 goto continue_loop; 2009 } 2010 block->dev_state = dev_state; 2011 block->dev_bytenr = dev_bytenr; 2012 block->logical_bytenr = bytenr; 2013 block->is_metadata = is_metadata; 2014 block->never_written = 0; 2015 block->iodone_w_error = 0; 2016 block->mirror_num = 0; /* unknown */ 2017 block->flush_gen = dev_state->last_flush_gen + 1; 2018 block->submit_bio_bh_rw = submit_bio_bh_rw; 2019 if (NULL != bio) { 2020 block->is_iodone = 0; 2021 BUG_ON(NULL == bio_is_patched); 2022 if (!*bio_is_patched) { 2023 block->orig_bio_private = bio->bi_private; 2024 block->orig_bio_end_io = bio->bi_end_io; 2025 block->next_in_same_bio = NULL; 2026 bio->bi_private = block; 2027 bio->bi_end_io = btrfsic_bio_end_io; 2028 *bio_is_patched = 1; 2029 } else { 2030 struct btrfsic_block *chained_block = 2031 (struct btrfsic_block *) 2032 bio->bi_private; 2033 2034 BUG_ON(NULL == chained_block); 2035 block->orig_bio_private = 2036 chained_block->orig_bio_private; 2037 block->orig_bio_end_io = 2038 chained_block->orig_bio_end_io; 2039 block->next_in_same_bio = chained_block; 2040 bio->bi_private = block; 2041 } 2042 } else { 2043 block->is_iodone = 1; 2044 block->orig_bio_private = NULL; 2045 block->orig_bio_end_io = NULL; 2046 block->next_in_same_bio = NULL; 2047 } 2048 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2049 pr_info("New written %c-block @%llu (%s/%llu/%d)\n", 2050 is_metadata ? 'M' : 'D', 2051 block->logical_bytenr, block->dev_state->name, 2052 block->dev_bytenr, block->mirror_num); 2053 list_add(&block->all_blocks_node, &state->all_blocks_list); 2054 btrfsic_block_hashtable_add(block, &state->block_hashtable); 2055 2056 if (is_metadata) { 2057 ret = btrfsic_process_metablock(state, block, 2058 &block_ctx, 0, 0); 2059 if (ret) 2060 pr_info("btrfsic: process_metablock(root @%llu) failed!\n", 2061 dev_bytenr); 2062 } 2063 btrfsic_release_block_ctx(&block_ctx); 2064 } 2065 2066 continue_loop: 2067 BUG_ON(!processed_len); 2068 dev_bytenr += processed_len; 2069 mapped_datav += processed_len >> PAGE_SHIFT; 2070 num_pages -= processed_len >> PAGE_SHIFT; 2071 goto again; 2072 } 2073 2074 static void btrfsic_bio_end_io(struct bio *bp) 2075 { 2076 struct btrfsic_block *block = (struct btrfsic_block *)bp->bi_private; 2077 int iodone_w_error; 2078 2079 /* mutex is not held! This is not save if IO is not yet completed 2080 * on umount */ 2081 iodone_w_error = 0; 2082 if (bp->bi_status) 2083 iodone_w_error = 1; 2084 2085 BUG_ON(NULL == block); 2086 bp->bi_private = block->orig_bio_private; 2087 bp->bi_end_io = block->orig_bio_end_io; 2088 2089 do { 2090 struct btrfsic_block *next_block; 2091 struct btrfsic_dev_state *const dev_state = block->dev_state; 2092 2093 if ((dev_state->state->print_mask & 2094 BTRFSIC_PRINT_MASK_END_IO_BIO_BH)) 2095 pr_info("bio_end_io(err=%d) for %c @%llu (%s/%llu/%d)\n", 2096 bp->bi_status, 2097 btrfsic_get_block_type(dev_state->state, block), 2098 block->logical_bytenr, dev_state->name, 2099 block->dev_bytenr, block->mirror_num); 2100 next_block = block->next_in_same_bio; 2101 block->iodone_w_error = iodone_w_error; 2102 if (block->submit_bio_bh_rw & REQ_PREFLUSH) { 2103 dev_state->last_flush_gen++; 2104 if ((dev_state->state->print_mask & 2105 BTRFSIC_PRINT_MASK_END_IO_BIO_BH)) 2106 pr_info("bio_end_io() new %s flush_gen=%llu\n", 2107 dev_state->name, 2108 dev_state->last_flush_gen); 2109 } 2110 if (block->submit_bio_bh_rw & REQ_FUA) 2111 block->flush_gen = 0; /* FUA completed means block is 2112 * on disk */ 2113 block->is_iodone = 1; /* for FLUSH, this releases the block */ 2114 block = next_block; 2115 } while (NULL != block); 2116 2117 bp->bi_end_io(bp); 2118 } 2119 2120 static int btrfsic_process_written_superblock( 2121 struct btrfsic_state *state, 2122 struct btrfsic_block *const superblock, 2123 struct btrfs_super_block *const super_hdr) 2124 { 2125 struct btrfs_fs_info *fs_info = state->fs_info; 2126 int pass; 2127 2128 superblock->generation = btrfs_super_generation(super_hdr); 2129 if (!(superblock->generation > state->max_superblock_generation || 2130 0 == state->max_superblock_generation)) { 2131 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE) 2132 pr_info("btrfsic: superblock @%llu (%s/%llu/%d) with old gen %llu <= %llu\n", 2133 superblock->logical_bytenr, 2134 superblock->dev_state->name, 2135 superblock->dev_bytenr, superblock->mirror_num, 2136 btrfs_super_generation(super_hdr), 2137 state->max_superblock_generation); 2138 } else { 2139 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE) 2140 pr_info("btrfsic: got new superblock @%llu (%s/%llu/%d) with new gen %llu > %llu\n", 2141 superblock->logical_bytenr, 2142 superblock->dev_state->name, 2143 superblock->dev_bytenr, superblock->mirror_num, 2144 btrfs_super_generation(super_hdr), 2145 state->max_superblock_generation); 2146 2147 state->max_superblock_generation = 2148 btrfs_super_generation(super_hdr); 2149 state->latest_superblock = superblock; 2150 } 2151 2152 for (pass = 0; pass < 3; pass++) { 2153 int ret; 2154 u64 next_bytenr; 2155 struct btrfsic_block *next_block; 2156 struct btrfsic_block_data_ctx tmp_next_block_ctx; 2157 struct btrfsic_block_link *l; 2158 int num_copies; 2159 int mirror_num; 2160 const char *additional_string = NULL; 2161 struct btrfs_disk_key tmp_disk_key = {0}; 2162 2163 btrfs_set_disk_key_objectid(&tmp_disk_key, 2164 BTRFS_ROOT_ITEM_KEY); 2165 btrfs_set_disk_key_objectid(&tmp_disk_key, 0); 2166 2167 switch (pass) { 2168 case 0: 2169 btrfs_set_disk_key_objectid(&tmp_disk_key, 2170 BTRFS_ROOT_TREE_OBJECTID); 2171 additional_string = "root "; 2172 next_bytenr = btrfs_super_root(super_hdr); 2173 if (state->print_mask & 2174 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 2175 pr_info("root@%llu\n", next_bytenr); 2176 break; 2177 case 1: 2178 btrfs_set_disk_key_objectid(&tmp_disk_key, 2179 BTRFS_CHUNK_TREE_OBJECTID); 2180 additional_string = "chunk "; 2181 next_bytenr = btrfs_super_chunk_root(super_hdr); 2182 if (state->print_mask & 2183 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 2184 pr_info("chunk@%llu\n", next_bytenr); 2185 break; 2186 case 2: 2187 btrfs_set_disk_key_objectid(&tmp_disk_key, 2188 BTRFS_TREE_LOG_OBJECTID); 2189 additional_string = "log "; 2190 next_bytenr = btrfs_super_log_root(super_hdr); 2191 if (0 == next_bytenr) 2192 continue; 2193 if (state->print_mask & 2194 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION) 2195 pr_info("log@%llu\n", next_bytenr); 2196 break; 2197 } 2198 2199 num_copies = btrfs_num_copies(fs_info, next_bytenr, 2200 BTRFS_SUPER_INFO_SIZE); 2201 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES) 2202 pr_info("num_copies(log_bytenr=%llu) = %d\n", 2203 next_bytenr, num_copies); 2204 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 2205 int was_created; 2206 2207 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2208 pr_info("btrfsic_process_written_superblock(mirror_num=%d)\n", mirror_num); 2209 ret = btrfsic_map_block(state, next_bytenr, 2210 BTRFS_SUPER_INFO_SIZE, 2211 &tmp_next_block_ctx, 2212 mirror_num); 2213 if (ret) { 2214 pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n", 2215 next_bytenr, mirror_num); 2216 return -1; 2217 } 2218 2219 next_block = btrfsic_block_lookup_or_add( 2220 state, 2221 &tmp_next_block_ctx, 2222 additional_string, 2223 1, 0, 1, 2224 mirror_num, 2225 &was_created); 2226 if (NULL == next_block) { 2227 btrfsic_release_block_ctx(&tmp_next_block_ctx); 2228 return -1; 2229 } 2230 2231 next_block->disk_key = tmp_disk_key; 2232 if (was_created) 2233 next_block->generation = 2234 BTRFSIC_GENERATION_UNKNOWN; 2235 l = btrfsic_block_link_lookup_or_add( 2236 state, 2237 &tmp_next_block_ctx, 2238 next_block, 2239 superblock, 2240 BTRFSIC_GENERATION_UNKNOWN); 2241 btrfsic_release_block_ctx(&tmp_next_block_ctx); 2242 if (NULL == l) 2243 return -1; 2244 } 2245 } 2246 2247 if (WARN_ON(-1 == btrfsic_check_all_ref_blocks(state, superblock, 0))) 2248 btrfsic_dump_tree(state); 2249 2250 return 0; 2251 } 2252 2253 static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state, 2254 struct btrfsic_block *const block, 2255 int recursion_level) 2256 { 2257 const struct btrfsic_block_link *l; 2258 int ret = 0; 2259 2260 if (recursion_level >= 3 + BTRFS_MAX_LEVEL) { 2261 /* 2262 * Note that this situation can happen and does not 2263 * indicate an error in regular cases. It happens 2264 * when disk blocks are freed and later reused. 2265 * The check-integrity module is not aware of any 2266 * block free operations, it just recognizes block 2267 * write operations. Therefore it keeps the linkage 2268 * information for a block until a block is 2269 * rewritten. This can temporarily cause incorrect 2270 * and even circular linkage information. This 2271 * causes no harm unless such blocks are referenced 2272 * by the most recent super block. 2273 */ 2274 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2275 pr_info("btrfsic: abort cyclic linkage (case 1).\n"); 2276 2277 return ret; 2278 } 2279 2280 /* 2281 * This algorithm is recursive because the amount of used stack 2282 * space is very small and the max recursion depth is limited. 2283 */ 2284 list_for_each_entry(l, &block->ref_to_list, node_ref_to) { 2285 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2286 pr_info("rl=%d, %c @%llu (%s/%llu/%d) %u* refers to %c @%llu (%s/%llu/%d)\n", 2287 recursion_level, 2288 btrfsic_get_block_type(state, block), 2289 block->logical_bytenr, block->dev_state->name, 2290 block->dev_bytenr, block->mirror_num, 2291 l->ref_cnt, 2292 btrfsic_get_block_type(state, l->block_ref_to), 2293 l->block_ref_to->logical_bytenr, 2294 l->block_ref_to->dev_state->name, 2295 l->block_ref_to->dev_bytenr, 2296 l->block_ref_to->mirror_num); 2297 if (l->block_ref_to->never_written) { 2298 pr_info("btrfs: attempt to write superblock which references block %c @%llu (%s/%llu/%d) which is never written!\n", 2299 btrfsic_get_block_type(state, l->block_ref_to), 2300 l->block_ref_to->logical_bytenr, 2301 l->block_ref_to->dev_state->name, 2302 l->block_ref_to->dev_bytenr, 2303 l->block_ref_to->mirror_num); 2304 ret = -1; 2305 } else if (!l->block_ref_to->is_iodone) { 2306 pr_info("btrfs: attempt to write superblock which references block %c @%llu (%s/%llu/%d) which is not yet iodone!\n", 2307 btrfsic_get_block_type(state, l->block_ref_to), 2308 l->block_ref_to->logical_bytenr, 2309 l->block_ref_to->dev_state->name, 2310 l->block_ref_to->dev_bytenr, 2311 l->block_ref_to->mirror_num); 2312 ret = -1; 2313 } else if (l->block_ref_to->iodone_w_error) { 2314 pr_info("btrfs: attempt to write superblock which references block %c @%llu (%s/%llu/%d) which has write error!\n", 2315 btrfsic_get_block_type(state, l->block_ref_to), 2316 l->block_ref_to->logical_bytenr, 2317 l->block_ref_to->dev_state->name, 2318 l->block_ref_to->dev_bytenr, 2319 l->block_ref_to->mirror_num); 2320 ret = -1; 2321 } else if (l->parent_generation != 2322 l->block_ref_to->generation && 2323 BTRFSIC_GENERATION_UNKNOWN != 2324 l->parent_generation && 2325 BTRFSIC_GENERATION_UNKNOWN != 2326 l->block_ref_to->generation) { 2327 pr_info("btrfs: attempt to write superblock which references block %c @%llu (%s/%llu/%d) with generation %llu != parent generation %llu!\n", 2328 btrfsic_get_block_type(state, l->block_ref_to), 2329 l->block_ref_to->logical_bytenr, 2330 l->block_ref_to->dev_state->name, 2331 l->block_ref_to->dev_bytenr, 2332 l->block_ref_to->mirror_num, 2333 l->block_ref_to->generation, 2334 l->parent_generation); 2335 ret = -1; 2336 } else if (l->block_ref_to->flush_gen > 2337 l->block_ref_to->dev_state->last_flush_gen) { 2338 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", 2339 btrfsic_get_block_type(state, l->block_ref_to), 2340 l->block_ref_to->logical_bytenr, 2341 l->block_ref_to->dev_state->name, 2342 l->block_ref_to->dev_bytenr, 2343 l->block_ref_to->mirror_num, block->flush_gen, 2344 l->block_ref_to->dev_state->last_flush_gen); 2345 ret = -1; 2346 } else if (-1 == btrfsic_check_all_ref_blocks(state, 2347 l->block_ref_to, 2348 recursion_level + 2349 1)) { 2350 ret = -1; 2351 } 2352 } 2353 2354 return ret; 2355 } 2356 2357 static int btrfsic_is_block_ref_by_superblock( 2358 const struct btrfsic_state *state, 2359 const struct btrfsic_block *block, 2360 int recursion_level) 2361 { 2362 const struct btrfsic_block_link *l; 2363 2364 if (recursion_level >= 3 + BTRFS_MAX_LEVEL) { 2365 /* refer to comment at "abort cyclic linkage (case 1)" */ 2366 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2367 pr_info("btrfsic: abort cyclic linkage (case 2).\n"); 2368 2369 return 0; 2370 } 2371 2372 /* 2373 * This algorithm is recursive because the amount of used stack space 2374 * is very small and the max recursion depth is limited. 2375 */ 2376 list_for_each_entry(l, &block->ref_from_list, node_ref_from) { 2377 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2378 pr_info("rl=%d, %c @%llu (%s/%llu/%d) is ref %u* from %c @%llu (%s/%llu/%d)\n", 2379 recursion_level, 2380 btrfsic_get_block_type(state, block), 2381 block->logical_bytenr, block->dev_state->name, 2382 block->dev_bytenr, block->mirror_num, 2383 l->ref_cnt, 2384 btrfsic_get_block_type(state, l->block_ref_from), 2385 l->block_ref_from->logical_bytenr, 2386 l->block_ref_from->dev_state->name, 2387 l->block_ref_from->dev_bytenr, 2388 l->block_ref_from->mirror_num); 2389 if (l->block_ref_from->is_superblock && 2390 state->latest_superblock->dev_bytenr == 2391 l->block_ref_from->dev_bytenr && 2392 state->latest_superblock->dev_state->bdev == 2393 l->block_ref_from->dev_state->bdev) 2394 return 1; 2395 else if (btrfsic_is_block_ref_by_superblock(state, 2396 l->block_ref_from, 2397 recursion_level + 2398 1)) 2399 return 1; 2400 } 2401 2402 return 0; 2403 } 2404 2405 static void btrfsic_print_add_link(const struct btrfsic_state *state, 2406 const struct btrfsic_block_link *l) 2407 { 2408 pr_info("Add %u* link from %c @%llu (%s/%llu/%d) to %c @%llu (%s/%llu/%d).\n", 2409 l->ref_cnt, 2410 btrfsic_get_block_type(state, l->block_ref_from), 2411 l->block_ref_from->logical_bytenr, 2412 l->block_ref_from->dev_state->name, 2413 l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num, 2414 btrfsic_get_block_type(state, l->block_ref_to), 2415 l->block_ref_to->logical_bytenr, 2416 l->block_ref_to->dev_state->name, l->block_ref_to->dev_bytenr, 2417 l->block_ref_to->mirror_num); 2418 } 2419 2420 static void btrfsic_print_rem_link(const struct btrfsic_state *state, 2421 const struct btrfsic_block_link *l) 2422 { 2423 pr_info("Rem %u* link from %c @%llu (%s/%llu/%d) to %c @%llu (%s/%llu/%d).\n", 2424 l->ref_cnt, 2425 btrfsic_get_block_type(state, l->block_ref_from), 2426 l->block_ref_from->logical_bytenr, 2427 l->block_ref_from->dev_state->name, 2428 l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num, 2429 btrfsic_get_block_type(state, l->block_ref_to), 2430 l->block_ref_to->logical_bytenr, 2431 l->block_ref_to->dev_state->name, l->block_ref_to->dev_bytenr, 2432 l->block_ref_to->mirror_num); 2433 } 2434 2435 static char btrfsic_get_block_type(const struct btrfsic_state *state, 2436 const struct btrfsic_block *block) 2437 { 2438 if (block->is_superblock && 2439 state->latest_superblock->dev_bytenr == block->dev_bytenr && 2440 state->latest_superblock->dev_state->bdev == block->dev_state->bdev) 2441 return 'S'; 2442 else if (block->is_superblock) 2443 return 's'; 2444 else if (block->is_metadata) 2445 return 'M'; 2446 else 2447 return 'D'; 2448 } 2449 2450 static void btrfsic_dump_tree(const struct btrfsic_state *state) 2451 { 2452 btrfsic_dump_tree_sub(state, state->latest_superblock, 0); 2453 } 2454 2455 static void btrfsic_dump_tree_sub(const struct btrfsic_state *state, 2456 const struct btrfsic_block *block, 2457 int indent_level) 2458 { 2459 const struct btrfsic_block_link *l; 2460 int indent_add; 2461 static char buf[80]; 2462 int cursor_position; 2463 2464 /* 2465 * Should better fill an on-stack buffer with a complete line and 2466 * dump it at once when it is time to print a newline character. 2467 */ 2468 2469 /* 2470 * This algorithm is recursive because the amount of used stack space 2471 * is very small and the max recursion depth is limited. 2472 */ 2473 indent_add = sprintf(buf, "%c-%llu(%s/%llu/%u)", 2474 btrfsic_get_block_type(state, block), 2475 block->logical_bytenr, block->dev_state->name, 2476 block->dev_bytenr, block->mirror_num); 2477 if (indent_level + indent_add > BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) { 2478 printk("[...]\n"); 2479 return; 2480 } 2481 printk(buf); 2482 indent_level += indent_add; 2483 if (list_empty(&block->ref_to_list)) { 2484 printk("\n"); 2485 return; 2486 } 2487 if (block->mirror_num > 1 && 2488 !(state->print_mask & BTRFSIC_PRINT_MASK_TREE_WITH_ALL_MIRRORS)) { 2489 printk(" [...]\n"); 2490 return; 2491 } 2492 2493 cursor_position = indent_level; 2494 list_for_each_entry(l, &block->ref_to_list, node_ref_to) { 2495 while (cursor_position < indent_level) { 2496 printk(" "); 2497 cursor_position++; 2498 } 2499 if (l->ref_cnt > 1) 2500 indent_add = sprintf(buf, " %d*--> ", l->ref_cnt); 2501 else 2502 indent_add = sprintf(buf, " --> "); 2503 if (indent_level + indent_add > 2504 BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) { 2505 printk("[...]\n"); 2506 cursor_position = 0; 2507 continue; 2508 } 2509 2510 printk(buf); 2511 2512 btrfsic_dump_tree_sub(state, l->block_ref_to, 2513 indent_level + indent_add); 2514 cursor_position = 0; 2515 } 2516 } 2517 2518 static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add( 2519 struct btrfsic_state *state, 2520 struct btrfsic_block_data_ctx *next_block_ctx, 2521 struct btrfsic_block *next_block, 2522 struct btrfsic_block *from_block, 2523 u64 parent_generation) 2524 { 2525 struct btrfsic_block_link *l; 2526 2527 l = btrfsic_block_link_hashtable_lookup(next_block_ctx->dev->bdev, 2528 next_block_ctx->dev_bytenr, 2529 from_block->dev_state->bdev, 2530 from_block->dev_bytenr, 2531 &state->block_link_hashtable); 2532 if (NULL == l) { 2533 l = btrfsic_block_link_alloc(); 2534 if (!l) 2535 return NULL; 2536 2537 l->block_ref_to = next_block; 2538 l->block_ref_from = from_block; 2539 l->ref_cnt = 1; 2540 l->parent_generation = parent_generation; 2541 2542 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2543 btrfsic_print_add_link(state, l); 2544 2545 list_add(&l->node_ref_to, &from_block->ref_to_list); 2546 list_add(&l->node_ref_from, &next_block->ref_from_list); 2547 2548 btrfsic_block_link_hashtable_add(l, 2549 &state->block_link_hashtable); 2550 } else { 2551 l->ref_cnt++; 2552 l->parent_generation = parent_generation; 2553 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2554 btrfsic_print_add_link(state, l); 2555 } 2556 2557 return l; 2558 } 2559 2560 static struct btrfsic_block *btrfsic_block_lookup_or_add( 2561 struct btrfsic_state *state, 2562 struct btrfsic_block_data_ctx *block_ctx, 2563 const char *additional_string, 2564 int is_metadata, 2565 int is_iodone, 2566 int never_written, 2567 int mirror_num, 2568 int *was_created) 2569 { 2570 struct btrfsic_block *block; 2571 2572 block = btrfsic_block_hashtable_lookup(block_ctx->dev->bdev, 2573 block_ctx->dev_bytenr, 2574 &state->block_hashtable); 2575 if (NULL == block) { 2576 struct btrfsic_dev_state *dev_state; 2577 2578 block = btrfsic_block_alloc(); 2579 if (!block) 2580 return NULL; 2581 2582 dev_state = btrfsic_dev_state_lookup(block_ctx->dev->bdev->bd_dev); 2583 if (NULL == dev_state) { 2584 pr_info("btrfsic: error, lookup dev_state failed!\n"); 2585 btrfsic_block_free(block); 2586 return NULL; 2587 } 2588 block->dev_state = dev_state; 2589 block->dev_bytenr = block_ctx->dev_bytenr; 2590 block->logical_bytenr = block_ctx->start; 2591 block->is_metadata = is_metadata; 2592 block->is_iodone = is_iodone; 2593 block->never_written = never_written; 2594 block->mirror_num = mirror_num; 2595 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2596 pr_info("New %s%c-block @%llu (%s/%llu/%d)\n", 2597 additional_string, 2598 btrfsic_get_block_type(state, block), 2599 block->logical_bytenr, dev_state->name, 2600 block->dev_bytenr, mirror_num); 2601 list_add(&block->all_blocks_node, &state->all_blocks_list); 2602 btrfsic_block_hashtable_add(block, &state->block_hashtable); 2603 if (NULL != was_created) 2604 *was_created = 1; 2605 } else { 2606 if (NULL != was_created) 2607 *was_created = 0; 2608 } 2609 2610 return block; 2611 } 2612 2613 static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state, 2614 u64 bytenr, 2615 struct btrfsic_dev_state *dev_state, 2616 u64 dev_bytenr) 2617 { 2618 struct btrfs_fs_info *fs_info = state->fs_info; 2619 struct btrfsic_block_data_ctx block_ctx; 2620 int num_copies; 2621 int mirror_num; 2622 int match = 0; 2623 int ret; 2624 2625 num_copies = btrfs_num_copies(fs_info, bytenr, state->metablock_size); 2626 2627 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 2628 ret = btrfsic_map_block(state, bytenr, state->metablock_size, 2629 &block_ctx, mirror_num); 2630 if (ret) { 2631 pr_info("btrfsic: btrfsic_map_block(logical @%llu, mirror %d) failed!\n", 2632 bytenr, mirror_num); 2633 continue; 2634 } 2635 2636 if (dev_state->bdev == block_ctx.dev->bdev && 2637 dev_bytenr == block_ctx.dev_bytenr) { 2638 match++; 2639 btrfsic_release_block_ctx(&block_ctx); 2640 break; 2641 } 2642 btrfsic_release_block_ctx(&block_ctx); 2643 } 2644 2645 if (WARN_ON(!match)) { 2646 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", 2647 bytenr, dev_state->name, dev_bytenr); 2648 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) { 2649 ret = btrfsic_map_block(state, bytenr, 2650 state->metablock_size, 2651 &block_ctx, mirror_num); 2652 if (ret) 2653 continue; 2654 2655 pr_info("Read logical bytenr @%llu maps to (%s/%llu/%d)\n", 2656 bytenr, block_ctx.dev->name, 2657 block_ctx.dev_bytenr, mirror_num); 2658 } 2659 } 2660 } 2661 2662 static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev) 2663 { 2664 return btrfsic_dev_state_hashtable_lookup(dev, 2665 &btrfsic_dev_state_hashtable); 2666 } 2667 2668 static void __btrfsic_submit_bio(struct bio *bio) 2669 { 2670 struct btrfsic_dev_state *dev_state; 2671 2672 if (!btrfsic_is_initialized) 2673 return; 2674 2675 mutex_lock(&btrfsic_mutex); 2676 /* since btrfsic_submit_bio() is also called before 2677 * btrfsic_mount(), this might return NULL */ 2678 dev_state = btrfsic_dev_state_lookup(bio->bi_bdev->bd_dev); 2679 if (NULL != dev_state && 2680 (bio_op(bio) == REQ_OP_WRITE) && bio_has_data(bio)) { 2681 int i = 0; 2682 u64 dev_bytenr; 2683 u64 cur_bytenr; 2684 struct bio_vec bvec; 2685 struct bvec_iter iter; 2686 int bio_is_patched; 2687 char **mapped_datav; 2688 unsigned int segs = bio_segments(bio); 2689 2690 dev_bytenr = 512 * bio->bi_iter.bi_sector; 2691 bio_is_patched = 0; 2692 if (dev_state->state->print_mask & 2693 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH) 2694 pr_info("submit_bio(rw=%d,0x%x, bi_vcnt=%u, bi_sector=%llu (bytenr %llu), bi_bdev=%p)\n", 2695 bio_op(bio), bio->bi_opf, segs, 2696 bio->bi_iter.bi_sector, dev_bytenr, bio->bi_bdev); 2697 2698 mapped_datav = kmalloc_array(segs, 2699 sizeof(*mapped_datav), GFP_NOFS); 2700 if (!mapped_datav) 2701 goto leave; 2702 cur_bytenr = dev_bytenr; 2703 2704 bio_for_each_segment(bvec, bio, iter) { 2705 BUG_ON(bvec.bv_len != PAGE_SIZE); 2706 mapped_datav[i] = kmap_local_page(bvec.bv_page); 2707 i++; 2708 2709 if (dev_state->state->print_mask & 2710 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE) 2711 pr_info("#%u: bytenr=%llu, len=%u, offset=%u\n", 2712 i, cur_bytenr, bvec.bv_len, bvec.bv_offset); 2713 cur_bytenr += bvec.bv_len; 2714 } 2715 btrfsic_process_written_block(dev_state, dev_bytenr, 2716 mapped_datav, segs, 2717 bio, &bio_is_patched, 2718 bio->bi_opf); 2719 /* Unmap in reverse order */ 2720 for (--i; i >= 0; i--) 2721 kunmap_local(mapped_datav[i]); 2722 kfree(mapped_datav); 2723 } else if (NULL != dev_state && (bio->bi_opf & REQ_PREFLUSH)) { 2724 if (dev_state->state->print_mask & 2725 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH) 2726 pr_info("submit_bio(rw=%d,0x%x FLUSH, bdev=%p)\n", 2727 bio_op(bio), bio->bi_opf, bio->bi_bdev); 2728 if (!dev_state->dummy_block_for_bio_bh_flush.is_iodone) { 2729 if ((dev_state->state->print_mask & 2730 (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH | 2731 BTRFSIC_PRINT_MASK_VERBOSE))) 2732 pr_info("btrfsic_submit_bio(%s) with FLUSH but dummy block already in use (ignored)!\n", 2733 dev_state->name); 2734 } else { 2735 struct btrfsic_block *const block = 2736 &dev_state->dummy_block_for_bio_bh_flush; 2737 2738 block->is_iodone = 0; 2739 block->never_written = 0; 2740 block->iodone_w_error = 0; 2741 block->flush_gen = dev_state->last_flush_gen + 1; 2742 block->submit_bio_bh_rw = bio->bi_opf; 2743 block->orig_bio_private = bio->bi_private; 2744 block->orig_bio_end_io = bio->bi_end_io; 2745 block->next_in_same_bio = NULL; 2746 bio->bi_private = block; 2747 bio->bi_end_io = btrfsic_bio_end_io; 2748 } 2749 } 2750 leave: 2751 mutex_unlock(&btrfsic_mutex); 2752 } 2753 2754 void btrfsic_submit_bio(struct bio *bio) 2755 { 2756 __btrfsic_submit_bio(bio); 2757 submit_bio(bio); 2758 } 2759 2760 int btrfsic_submit_bio_wait(struct bio *bio) 2761 { 2762 __btrfsic_submit_bio(bio); 2763 return submit_bio_wait(bio); 2764 } 2765 2766 int btrfsic_mount(struct btrfs_fs_info *fs_info, 2767 struct btrfs_fs_devices *fs_devices, 2768 int including_extent_data, u32 print_mask) 2769 { 2770 int ret; 2771 struct btrfsic_state *state; 2772 struct list_head *dev_head = &fs_devices->devices; 2773 struct btrfs_device *device; 2774 2775 if (!PAGE_ALIGNED(fs_info->nodesize)) { 2776 pr_info("btrfsic: cannot handle nodesize %d not being a multiple of PAGE_SIZE %ld!\n", 2777 fs_info->nodesize, PAGE_SIZE); 2778 return -1; 2779 } 2780 if (!PAGE_ALIGNED(fs_info->sectorsize)) { 2781 pr_info("btrfsic: cannot handle sectorsize %d not being a multiple of PAGE_SIZE %ld!\n", 2782 fs_info->sectorsize, PAGE_SIZE); 2783 return -1; 2784 } 2785 state = kvzalloc(sizeof(*state), GFP_KERNEL); 2786 if (!state) 2787 return -ENOMEM; 2788 2789 if (!btrfsic_is_initialized) { 2790 mutex_init(&btrfsic_mutex); 2791 btrfsic_dev_state_hashtable_init(&btrfsic_dev_state_hashtable); 2792 btrfsic_is_initialized = 1; 2793 } 2794 mutex_lock(&btrfsic_mutex); 2795 state->fs_info = fs_info; 2796 state->print_mask = print_mask; 2797 state->include_extent_data = including_extent_data; 2798 state->metablock_size = fs_info->nodesize; 2799 state->datablock_size = fs_info->sectorsize; 2800 INIT_LIST_HEAD(&state->all_blocks_list); 2801 btrfsic_block_hashtable_init(&state->block_hashtable); 2802 btrfsic_block_link_hashtable_init(&state->block_link_hashtable); 2803 state->max_superblock_generation = 0; 2804 state->latest_superblock = NULL; 2805 2806 list_for_each_entry(device, dev_head, dev_list) { 2807 struct btrfsic_dev_state *ds; 2808 const char *p; 2809 2810 if (!device->bdev || !device->name) 2811 continue; 2812 2813 ds = btrfsic_dev_state_alloc(); 2814 if (NULL == ds) { 2815 mutex_unlock(&btrfsic_mutex); 2816 return -ENOMEM; 2817 } 2818 ds->bdev = device->bdev; 2819 ds->state = state; 2820 bdevname(ds->bdev, ds->name); 2821 ds->name[BDEVNAME_SIZE - 1] = '\0'; 2822 p = kbasename(ds->name); 2823 strlcpy(ds->name, p, sizeof(ds->name)); 2824 btrfsic_dev_state_hashtable_add(ds, 2825 &btrfsic_dev_state_hashtable); 2826 } 2827 2828 ret = btrfsic_process_superblock(state, fs_devices); 2829 if (0 != ret) { 2830 mutex_unlock(&btrfsic_mutex); 2831 btrfsic_unmount(fs_devices); 2832 return ret; 2833 } 2834 2835 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_DATABASE) 2836 btrfsic_dump_database(state); 2837 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_TREE) 2838 btrfsic_dump_tree(state); 2839 2840 mutex_unlock(&btrfsic_mutex); 2841 return 0; 2842 } 2843 2844 void btrfsic_unmount(struct btrfs_fs_devices *fs_devices) 2845 { 2846 struct btrfsic_block *b_all, *tmp_all; 2847 struct btrfsic_state *state; 2848 struct list_head *dev_head = &fs_devices->devices; 2849 struct btrfs_device *device; 2850 2851 if (!btrfsic_is_initialized) 2852 return; 2853 2854 mutex_lock(&btrfsic_mutex); 2855 2856 state = NULL; 2857 list_for_each_entry(device, dev_head, dev_list) { 2858 struct btrfsic_dev_state *ds; 2859 2860 if (!device->bdev || !device->name) 2861 continue; 2862 2863 ds = btrfsic_dev_state_hashtable_lookup( 2864 device->bdev->bd_dev, 2865 &btrfsic_dev_state_hashtable); 2866 if (NULL != ds) { 2867 state = ds->state; 2868 btrfsic_dev_state_hashtable_remove(ds); 2869 btrfsic_dev_state_free(ds); 2870 } 2871 } 2872 2873 if (NULL == state) { 2874 pr_info("btrfsic: error, cannot find state information on umount!\n"); 2875 mutex_unlock(&btrfsic_mutex); 2876 return; 2877 } 2878 2879 /* 2880 * Don't care about keeping the lists' state up to date, 2881 * just free all memory that was allocated dynamically. 2882 * Free the blocks and the block_links. 2883 */ 2884 list_for_each_entry_safe(b_all, tmp_all, &state->all_blocks_list, 2885 all_blocks_node) { 2886 struct btrfsic_block_link *l, *tmp; 2887 2888 list_for_each_entry_safe(l, tmp, &b_all->ref_to_list, 2889 node_ref_to) { 2890 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) 2891 btrfsic_print_rem_link(state, l); 2892 2893 l->ref_cnt--; 2894 if (0 == l->ref_cnt) 2895 btrfsic_block_link_free(l); 2896 } 2897 2898 if (b_all->is_iodone || b_all->never_written) 2899 btrfsic_block_free(b_all); 2900 else 2901 pr_info("btrfs: attempt to free %c-block @%llu (%s/%llu/%d) on umount which is not yet iodone!\n", 2902 btrfsic_get_block_type(state, b_all), 2903 b_all->logical_bytenr, b_all->dev_state->name, 2904 b_all->dev_bytenr, b_all->mirror_num); 2905 } 2906 2907 mutex_unlock(&btrfsic_mutex); 2908 2909 kvfree(state); 2910 } 2911