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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/buffer_head.h>
81#include <linux/mutex.h>
82#include <linux/genhd.h>
83#include <linux/blkdev.h>
84#include <linux/mm.h>
85#include <linux/string.h>
86#include <linux/crc32c.h>
87#include "ctree.h"
88#include "disk-io.h"
89#include "transaction.h"
90#include "extent_io.h"
91#include "volumes.h"
92#include "print-tree.h"
93#include "locking.h"
94#include "check-integrity.h"
95#include "rcu-string.h"
96#include "compression.h"
97
98#define BTRFSIC_BLOCK_HASHTABLE_SIZE 0x10000
99#define BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE 0x10000
100#define BTRFSIC_DEV2STATE_HASHTABLE_SIZE 0x100
101#define BTRFSIC_BLOCK_MAGIC_NUMBER 0x14491051
102#define BTRFSIC_BLOCK_LINK_MAGIC_NUMBER 0x11070807
103#define BTRFSIC_DEV2STATE_MAGIC_NUMBER 0x20111530
104#define BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER 20111300
105#define BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL (200 - 6) /* in characters,
106 * excluding " [...]" */
107#define BTRFSIC_GENERATION_UNKNOWN ((u64)-1)
108
109/*
110 * The definition of the bitmask fields for the print_mask.
111 * They are specified with the mount option check_integrity_print_mask.
112 */
113#define BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE 0x00000001
114#define BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION 0x00000002
115#define BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE 0x00000004
116#define BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE 0x00000008
117#define BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH 0x00000010
118#define BTRFSIC_PRINT_MASK_END_IO_BIO_BH 0x00000020
119#define BTRFSIC_PRINT_MASK_VERBOSE 0x00000040
120#define BTRFSIC_PRINT_MASK_VERY_VERBOSE 0x00000080
121#define BTRFSIC_PRINT_MASK_INITIAL_TREE 0x00000100
122#define BTRFSIC_PRINT_MASK_INITIAL_ALL_TREES 0x00000200
123#define BTRFSIC_PRINT_MASK_INITIAL_DATABASE 0x00000400
124#define BTRFSIC_PRINT_MASK_NUM_COPIES 0x00000800
125#define BTRFSIC_PRINT_MASK_TREE_WITH_ALL_MIRRORS 0x00001000
126#define BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE 0x00002000
127
128struct btrfsic_dev_state;
129struct btrfsic_state;
130
131struct btrfsic_block {
132 u32 magic_num; /* only used for debug purposes */
133 unsigned int is_metadata:1; /* if it is meta-data, not data-data */
134 unsigned int is_superblock:1; /* if it is one of the superblocks */
135 unsigned int is_iodone:1; /* if is done by lower subsystem */
136 unsigned int iodone_w_error:1; /* error was indicated to endio */
137 unsigned int never_written:1; /* block was added because it was
138 * referenced, not because it was
139 * written */
140 unsigned int mirror_num; /* large enough to hold
141 * BTRFS_SUPER_MIRROR_MAX */
142 struct btrfsic_dev_state *dev_state;
143 u64 dev_bytenr; /* key, physical byte num on disk */
144 u64 logical_bytenr; /* logical byte num on disk */
145 u64 generation;
146 struct btrfs_disk_key disk_key; /* extra info to print in case of
147 * issues, will not always be correct */
148 struct list_head collision_resolving_node; /* list node */
149 struct list_head all_blocks_node; /* list node */
150
151 /* the following two lists contain block_link items */
152 struct list_head ref_to_list; /* list */
153 struct list_head ref_from_list; /* list */
154 struct btrfsic_block *next_in_same_bio;
155 void *orig_bio_bh_private;
156 union {
157 bio_end_io_t *bio;
158 bh_end_io_t *bh;
159 } orig_bio_bh_end_io;
160 int submit_bio_bh_rw;
161 u64 flush_gen; /* only valid if !never_written */
162};
163
164/*
165 * Elements of this type are allocated dynamically and required because
166 * each block object can refer to and can be ref from multiple blocks.
167 * The key to lookup them in the hashtable is the dev_bytenr of
168 * the block ref to plus the one from the block referred from.
169 * The fact that they are searchable via a hashtable and that a
170 * ref_cnt is maintained is not required for the btrfs integrity
171 * check algorithm itself, it is only used to make the output more
172 * beautiful in case that an error is detected (an error is defined
173 * as a write operation to a block while that block is still referenced).
174 */
175struct btrfsic_block_link {
176 u32 magic_num; /* only used for debug purposes */
177 u32 ref_cnt;
178 struct list_head node_ref_to; /* list node */
179 struct list_head node_ref_from; /* list node */
180 struct list_head collision_resolving_node; /* list node */
181 struct btrfsic_block *block_ref_to;
182 struct btrfsic_block *block_ref_from;
183 u64 parent_generation;
184};
185
186struct btrfsic_dev_state {
187 u32 magic_num; /* only used for debug purposes */
188 struct block_device *bdev;
189 struct btrfsic_state *state;
190 struct list_head collision_resolving_node; /* list node */
191 struct btrfsic_block dummy_block_for_bio_bh_flush;
192 u64 last_flush_gen;
193 char name[BDEVNAME_SIZE];
194};
195
196struct btrfsic_block_hashtable {
197 struct list_head table[BTRFSIC_BLOCK_HASHTABLE_SIZE];
198};
199
200struct btrfsic_block_link_hashtable {
201 struct list_head table[BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE];
202};
203
204struct btrfsic_dev_state_hashtable {
205 struct list_head table[BTRFSIC_DEV2STATE_HASHTABLE_SIZE];
206};
207
208struct btrfsic_block_data_ctx {
209 u64 start; /* virtual bytenr */
210 u64 dev_bytenr; /* physical bytenr on device */
211 u32 len;
212 struct btrfsic_dev_state *dev;
213 char **datav;
214 struct page **pagev;
215 void *mem_to_free;
216};
217
218/* This structure is used to implement recursion without occupying
219 * any stack space, refer to btrfsic_process_metablock() */
220struct btrfsic_stack_frame {
221 u32 magic;
222 u32 nr;
223 int error;
224 int i;
225 int limit_nesting;
226 int num_copies;
227 int mirror_num;
228 struct btrfsic_block *block;
229 struct btrfsic_block_data_ctx *block_ctx;
230 struct btrfsic_block *next_block;
231 struct btrfsic_block_data_ctx next_block_ctx;
232 struct btrfs_header *hdr;
233 struct btrfsic_stack_frame *prev;
234};
235
236/* Some state per mounted filesystem */
237struct btrfsic_state {
238 u32 print_mask;
239 int include_extent_data;
240 int csum_size;
241 struct list_head all_blocks_list;
242 struct btrfsic_block_hashtable block_hashtable;
243 struct btrfsic_block_link_hashtable block_link_hashtable;
244 struct btrfs_fs_info *fs_info;
245 u64 max_superblock_generation;
246 struct btrfsic_block *latest_superblock;
247 u32 metablock_size;
248 u32 datablock_size;
249};
250
251static void btrfsic_block_init(struct btrfsic_block *b);
252static struct btrfsic_block *btrfsic_block_alloc(void);
253static void btrfsic_block_free(struct btrfsic_block *b);
254static void btrfsic_block_link_init(struct btrfsic_block_link *n);
255static struct btrfsic_block_link *btrfsic_block_link_alloc(void);
256static void btrfsic_block_link_free(struct btrfsic_block_link *n);
257static void btrfsic_dev_state_init(struct btrfsic_dev_state *ds);
258static struct btrfsic_dev_state *btrfsic_dev_state_alloc(void);
259static void btrfsic_dev_state_free(struct btrfsic_dev_state *ds);
260static void btrfsic_block_hashtable_init(struct btrfsic_block_hashtable *h);
261static void btrfsic_block_hashtable_add(struct btrfsic_block *b,
262 struct btrfsic_block_hashtable *h);
263static void btrfsic_block_hashtable_remove(struct btrfsic_block *b);
264static struct btrfsic_block *btrfsic_block_hashtable_lookup(
265 struct block_device *bdev,
266 u64 dev_bytenr,
267 struct btrfsic_block_hashtable *h);
268static void btrfsic_block_link_hashtable_init(
269 struct btrfsic_block_link_hashtable *h);
270static void btrfsic_block_link_hashtable_add(
271 struct btrfsic_block_link *l,
272 struct btrfsic_block_link_hashtable *h);
273static void btrfsic_block_link_hashtable_remove(struct btrfsic_block_link *l);
274static struct btrfsic_block_link *btrfsic_block_link_hashtable_lookup(
275 struct block_device *bdev_ref_to,
276 u64 dev_bytenr_ref_to,
277 struct block_device *bdev_ref_from,
278 u64 dev_bytenr_ref_from,
279 struct btrfsic_block_link_hashtable *h);
280static void btrfsic_dev_state_hashtable_init(
281 struct btrfsic_dev_state_hashtable *h);
282static void btrfsic_dev_state_hashtable_add(
283 struct btrfsic_dev_state *ds,
284 struct btrfsic_dev_state_hashtable *h);
285static void btrfsic_dev_state_hashtable_remove(struct btrfsic_dev_state *ds);
286static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(dev_t dev,
287 struct btrfsic_dev_state_hashtable *h);
288static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void);
289static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf);
290static int btrfsic_process_superblock(struct btrfsic_state *state,
291 struct btrfs_fs_devices *fs_devices);
292static int btrfsic_process_metablock(struct btrfsic_state *state,
293 struct btrfsic_block *block,
294 struct btrfsic_block_data_ctx *block_ctx,
295 int limit_nesting, int force_iodone_flag);
296static void btrfsic_read_from_block_data(
297 struct btrfsic_block_data_ctx *block_ctx,
298 void *dst, u32 offset, size_t len);
299static int btrfsic_create_link_to_next_block(
300 struct btrfsic_state *state,
301 struct btrfsic_block *block,
302 struct btrfsic_block_data_ctx
303 *block_ctx, u64 next_bytenr,
304 int limit_nesting,
305 struct btrfsic_block_data_ctx *next_block_ctx,
306 struct btrfsic_block **next_blockp,
307 int force_iodone_flag,
308 int *num_copiesp, int *mirror_nump,
309 struct btrfs_disk_key *disk_key,
310 u64 parent_generation);
311static int btrfsic_handle_extent_data(struct btrfsic_state *state,
312 struct btrfsic_block *block,
313 struct btrfsic_block_data_ctx *block_ctx,
314 u32 item_offset, int force_iodone_flag);
315static int btrfsic_map_block(struct btrfsic_state *state, u64 bytenr, u32 len,
316 struct btrfsic_block_data_ctx *block_ctx_out,
317 int mirror_num);
318static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx);
319static int btrfsic_read_block(struct btrfsic_state *state,
320 struct btrfsic_block_data_ctx *block_ctx);
321static void btrfsic_dump_database(struct btrfsic_state *state);
322static int btrfsic_test_for_metadata(struct btrfsic_state *state,
323 char **datav, unsigned int num_pages);
324static void btrfsic_process_written_block(struct btrfsic_dev_state *dev_state,
325 u64 dev_bytenr, char **mapped_datav,
326 unsigned int num_pages,
327 struct bio *bio, int *bio_is_patched,
328 struct buffer_head *bh,
329 int submit_bio_bh_rw);
330static int btrfsic_process_written_superblock(
331 struct btrfsic_state *state,
332 struct btrfsic_block *const block,
333 struct btrfs_super_block *const super_hdr);
334static void btrfsic_bio_end_io(struct bio *bp);
335static void btrfsic_bh_end_io(struct buffer_head *bh, int uptodate);
336static int btrfsic_is_block_ref_by_superblock(const struct btrfsic_state *state,
337 const struct btrfsic_block *block,
338 int recursion_level);
339static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state,
340 struct btrfsic_block *const block,
341 int recursion_level);
342static void btrfsic_print_add_link(const struct btrfsic_state *state,
343 const struct btrfsic_block_link *l);
344static void btrfsic_print_rem_link(const struct btrfsic_state *state,
345 const struct btrfsic_block_link *l);
346static char btrfsic_get_block_type(const struct btrfsic_state *state,
347 const struct btrfsic_block *block);
348static void btrfsic_dump_tree(const struct btrfsic_state *state);
349static void btrfsic_dump_tree_sub(const struct btrfsic_state *state,
350 const struct btrfsic_block *block,
351 int indent_level);
352static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add(
353 struct btrfsic_state *state,
354 struct btrfsic_block_data_ctx *next_block_ctx,
355 struct btrfsic_block *next_block,
356 struct btrfsic_block *from_block,
357 u64 parent_generation);
358static struct btrfsic_block *btrfsic_block_lookup_or_add(
359 struct btrfsic_state *state,
360 struct btrfsic_block_data_ctx *block_ctx,
361 const char *additional_string,
362 int is_metadata,
363 int is_iodone,
364 int never_written,
365 int mirror_num,
366 int *was_created);
367static int btrfsic_process_superblock_dev_mirror(
368 struct btrfsic_state *state,
369 struct btrfsic_dev_state *dev_state,
370 struct btrfs_device *device,
371 int superblock_mirror_num,
372 struct btrfsic_dev_state **selected_dev_state,
373 struct btrfs_super_block *selected_super);
374static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev);
375static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state,
376 u64 bytenr,
377 struct btrfsic_dev_state *dev_state,
378 u64 dev_bytenr);
379
380static struct mutex btrfsic_mutex;
381static int btrfsic_is_initialized;
382static struct btrfsic_dev_state_hashtable btrfsic_dev_state_hashtable;
383
384
385static void btrfsic_block_init(struct btrfsic_block *b)
386{
387 b->magic_num = BTRFSIC_BLOCK_MAGIC_NUMBER;
388 b->dev_state = NULL;
389 b->dev_bytenr = 0;
390 b->logical_bytenr = 0;
391 b->generation = BTRFSIC_GENERATION_UNKNOWN;
392 b->disk_key.objectid = 0;
393 b->disk_key.type = 0;
394 b->disk_key.offset = 0;
395 b->is_metadata = 0;
396 b->is_superblock = 0;
397 b->is_iodone = 0;
398 b->iodone_w_error = 0;
399 b->never_written = 0;
400 b->mirror_num = 0;
401 b->next_in_same_bio = NULL;
402 b->orig_bio_bh_private = NULL;
403 b->orig_bio_bh_end_io.bio = NULL;
404 INIT_LIST_HEAD(&b->collision_resolving_node);
405 INIT_LIST_HEAD(&b->all_blocks_node);
406 INIT_LIST_HEAD(&b->ref_to_list);
407 INIT_LIST_HEAD(&b->ref_from_list);
408 b->submit_bio_bh_rw = 0;
409 b->flush_gen = 0;
410}
411
412static struct btrfsic_block *btrfsic_block_alloc(void)
413{
414 struct btrfsic_block *b;
415
416 b = kzalloc(sizeof(*b), GFP_NOFS);
417 if (NULL != b)
418 btrfsic_block_init(b);
419
420 return b;
421}
422
423static void btrfsic_block_free(struct btrfsic_block *b)
424{
425 BUG_ON(!(NULL == b || BTRFSIC_BLOCK_MAGIC_NUMBER == b->magic_num));
426 kfree(b);
427}
428
429static void btrfsic_block_link_init(struct btrfsic_block_link *l)
430{
431 l->magic_num = BTRFSIC_BLOCK_LINK_MAGIC_NUMBER;
432 l->ref_cnt = 1;
433 INIT_LIST_HEAD(&l->node_ref_to);
434 INIT_LIST_HEAD(&l->node_ref_from);
435 INIT_LIST_HEAD(&l->collision_resolving_node);
436 l->block_ref_to = NULL;
437 l->block_ref_from = NULL;
438}
439
440static struct btrfsic_block_link *btrfsic_block_link_alloc(void)
441{
442 struct btrfsic_block_link *l;
443
444 l = kzalloc(sizeof(*l), GFP_NOFS);
445 if (NULL != l)
446 btrfsic_block_link_init(l);
447
448 return l;
449}
450
451static void btrfsic_block_link_free(struct btrfsic_block_link *l)
452{
453 BUG_ON(!(NULL == l || BTRFSIC_BLOCK_LINK_MAGIC_NUMBER == l->magic_num));
454 kfree(l);
455}
456
457static void btrfsic_dev_state_init(struct btrfsic_dev_state *ds)
458{
459 ds->magic_num = BTRFSIC_DEV2STATE_MAGIC_NUMBER;
460 ds->bdev = NULL;
461 ds->state = NULL;
462 ds->name[0] = '\0';
463 INIT_LIST_HEAD(&ds->collision_resolving_node);
464 ds->last_flush_gen = 0;
465 btrfsic_block_init(&ds->dummy_block_for_bio_bh_flush);
466 ds->dummy_block_for_bio_bh_flush.is_iodone = 1;
467 ds->dummy_block_for_bio_bh_flush.dev_state = ds;
468}
469
470static struct btrfsic_dev_state *btrfsic_dev_state_alloc(void)
471{
472 struct btrfsic_dev_state *ds;
473
474 ds = kzalloc(sizeof(*ds), GFP_NOFS);
475 if (NULL != ds)
476 btrfsic_dev_state_init(ds);
477
478 return ds;
479}
480
481static void btrfsic_dev_state_free(struct btrfsic_dev_state *ds)
482{
483 BUG_ON(!(NULL == ds ||
484 BTRFSIC_DEV2STATE_MAGIC_NUMBER == ds->magic_num));
485 kfree(ds);
486}
487
488static void btrfsic_block_hashtable_init(struct btrfsic_block_hashtable *h)
489{
490 int i;
491
492 for (i = 0; i < BTRFSIC_BLOCK_HASHTABLE_SIZE; i++)
493 INIT_LIST_HEAD(h->table + i);
494}
495
496static void btrfsic_block_hashtable_add(struct btrfsic_block *b,
497 struct btrfsic_block_hashtable *h)
498{
499 const unsigned int hashval =
500 (((unsigned int)(b->dev_bytenr >> 16)) ^
501 ((unsigned int)((uintptr_t)b->dev_state->bdev))) &
502 (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1);
503
504 list_add(&b->collision_resolving_node, h->table + hashval);
505}
506
507static void btrfsic_block_hashtable_remove(struct btrfsic_block *b)
508{
509 list_del(&b->collision_resolving_node);
510}
511
512static struct btrfsic_block *btrfsic_block_hashtable_lookup(
513 struct block_device *bdev,
514 u64 dev_bytenr,
515 struct btrfsic_block_hashtable *h)
516{
517 const unsigned int hashval =
518 (((unsigned int)(dev_bytenr >> 16)) ^
519 ((unsigned int)((uintptr_t)bdev))) &
520 (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1);
521 struct btrfsic_block *b;
522
523 list_for_each_entry(b, h->table + hashval, collision_resolving_node) {
524 if (b->dev_state->bdev == bdev && b->dev_bytenr == dev_bytenr)
525 return b;
526 }
527
528 return NULL;
529}
530
531static void btrfsic_block_link_hashtable_init(
532 struct btrfsic_block_link_hashtable *h)
533{
534 int i;
535
536 for (i = 0; i < BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE; i++)
537 INIT_LIST_HEAD(h->table + i);
538}
539
540static void btrfsic_block_link_hashtable_add(
541 struct btrfsic_block_link *l,
542 struct btrfsic_block_link_hashtable *h)
543{
544 const unsigned int hashval =
545 (((unsigned int)(l->block_ref_to->dev_bytenr >> 16)) ^
546 ((unsigned int)(l->block_ref_from->dev_bytenr >> 16)) ^
547 ((unsigned int)((uintptr_t)l->block_ref_to->dev_state->bdev)) ^
548 ((unsigned int)((uintptr_t)l->block_ref_from->dev_state->bdev)))
549 & (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1);
550
551 BUG_ON(NULL == l->block_ref_to);
552 BUG_ON(NULL == l->block_ref_from);
553 list_add(&l->collision_resolving_node, h->table + hashval);
554}
555
556static void btrfsic_block_link_hashtable_remove(struct btrfsic_block_link *l)
557{
558 list_del(&l->collision_resolving_node);
559}
560
561static struct btrfsic_block_link *btrfsic_block_link_hashtable_lookup(
562 struct block_device *bdev_ref_to,
563 u64 dev_bytenr_ref_to,
564 struct block_device *bdev_ref_from,
565 u64 dev_bytenr_ref_from,
566 struct btrfsic_block_link_hashtable *h)
567{
568 const unsigned int hashval =
569 (((unsigned int)(dev_bytenr_ref_to >> 16)) ^
570 ((unsigned int)(dev_bytenr_ref_from >> 16)) ^
571 ((unsigned int)((uintptr_t)bdev_ref_to)) ^
572 ((unsigned int)((uintptr_t)bdev_ref_from))) &
573 (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1);
574 struct btrfsic_block_link *l;
575
576 list_for_each_entry(l, h->table + hashval, collision_resolving_node) {
577 BUG_ON(NULL == l->block_ref_to);
578 BUG_ON(NULL == l->block_ref_from);
579 if (l->block_ref_to->dev_state->bdev == bdev_ref_to &&
580 l->block_ref_to->dev_bytenr == dev_bytenr_ref_to &&
581 l->block_ref_from->dev_state->bdev == bdev_ref_from &&
582 l->block_ref_from->dev_bytenr == dev_bytenr_ref_from)
583 return l;
584 }
585
586 return NULL;
587}
588
589static void btrfsic_dev_state_hashtable_init(
590 struct btrfsic_dev_state_hashtable *h)
591{
592 int i;
593
594 for (i = 0; i < BTRFSIC_DEV2STATE_HASHTABLE_SIZE; i++)
595 INIT_LIST_HEAD(h->table + i);
596}
597
598static void btrfsic_dev_state_hashtable_add(
599 struct btrfsic_dev_state *ds,
600 struct btrfsic_dev_state_hashtable *h)
601{
602 const unsigned int hashval =
603 (((unsigned int)((uintptr_t)ds->bdev->bd_dev)) &
604 (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1));
605
606 list_add(&ds->collision_resolving_node, h->table + hashval);
607}
608
609static void btrfsic_dev_state_hashtable_remove(struct btrfsic_dev_state *ds)
610{
611 list_del(&ds->collision_resolving_node);
612}
613
614static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(dev_t dev,
615 struct btrfsic_dev_state_hashtable *h)
616{
617 const unsigned int hashval =
618 dev & (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1);
619 struct btrfsic_dev_state *ds;
620
621 list_for_each_entry(ds, h->table + hashval, collision_resolving_node) {
622 if (ds->bdev->bd_dev == dev)
623 return ds;
624 }
625
626 return NULL;
627}
628
629static int btrfsic_process_superblock(struct btrfsic_state *state,
630 struct btrfs_fs_devices *fs_devices)
631{
632 struct btrfs_fs_info *fs_info = state->fs_info;
633 struct btrfs_super_block *selected_super;
634 struct list_head *dev_head = &fs_devices->devices;
635 struct btrfs_device *device;
636 struct btrfsic_dev_state *selected_dev_state = NULL;
637 int ret = 0;
638 int pass;
639
640 BUG_ON(NULL == state);
641 selected_super = kzalloc(sizeof(*selected_super), GFP_NOFS);
642 if (NULL == selected_super) {
643 pr_info("btrfsic: error, kmalloc failed!\n");
644 return -ENOMEM;
645 }
646
647 list_for_each_entry(device, dev_head, dev_list) {
648 int i;
649 struct btrfsic_dev_state *dev_state;
650
651 if (!device->bdev || !device->name)
652 continue;
653
654 dev_state = btrfsic_dev_state_lookup(device->bdev->bd_dev);
655 BUG_ON(NULL == dev_state);
656 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
657 ret = btrfsic_process_superblock_dev_mirror(
658 state, dev_state, device, i,
659 &selected_dev_state, selected_super);
660 if (0 != ret && 0 == i) {
661 kfree(selected_super);
662 return ret;
663 }
664 }
665 }
666
667 if (NULL == state->latest_superblock) {
668 pr_info("btrfsic: no superblock found!\n");
669 kfree(selected_super);
670 return -1;
671 }
672
673 state->csum_size = btrfs_super_csum_size(selected_super);
674
675 for (pass = 0; pass < 3; pass++) {
676 int num_copies;
677 int mirror_num;
678 u64 next_bytenr;
679
680 switch (pass) {
681 case 0:
682 next_bytenr = btrfs_super_root(selected_super);
683 if (state->print_mask &
684 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
685 pr_info("root@%llu\n", next_bytenr);
686 break;
687 case 1:
688 next_bytenr = btrfs_super_chunk_root(selected_super);
689 if (state->print_mask &
690 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
691 pr_info("chunk@%llu\n", next_bytenr);
692 break;
693 case 2:
694 next_bytenr = btrfs_super_log_root(selected_super);
695 if (0 == next_bytenr)
696 continue;
697 if (state->print_mask &
698 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
699 pr_info("log@%llu\n", next_bytenr);
700 break;
701 }
702
703 num_copies = btrfs_num_copies(fs_info, next_bytenr,
704 state->metablock_size);
705 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
706 pr_info("num_copies(log_bytenr=%llu) = %d\n",
707 next_bytenr, num_copies);
708
709 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
710 struct btrfsic_block *next_block;
711 struct btrfsic_block_data_ctx tmp_next_block_ctx;
712 struct btrfsic_block_link *l;
713
714 ret = btrfsic_map_block(state, next_bytenr,
715 state->metablock_size,
716 &tmp_next_block_ctx,
717 mirror_num);
718 if (ret) {
719 pr_info("btrfsic: btrfsic_map_block(root @%llu, mirror %d) failed!\n",
720 next_bytenr, mirror_num);
721 kfree(selected_super);
722 return -1;
723 }
724
725 next_block = btrfsic_block_hashtable_lookup(
726 tmp_next_block_ctx.dev->bdev,
727 tmp_next_block_ctx.dev_bytenr,
728 &state->block_hashtable);
729 BUG_ON(NULL == next_block);
730
731 l = btrfsic_block_link_hashtable_lookup(
732 tmp_next_block_ctx.dev->bdev,
733 tmp_next_block_ctx.dev_bytenr,
734 state->latest_superblock->dev_state->
735 bdev,
736 state->latest_superblock->dev_bytenr,
737 &state->block_link_hashtable);
738 BUG_ON(NULL == l);
739
740 ret = btrfsic_read_block(state, &tmp_next_block_ctx);
741 if (ret < (int)PAGE_SIZE) {
742 pr_info("btrfsic: read @logical %llu failed!\n",
743 tmp_next_block_ctx.start);
744 btrfsic_release_block_ctx(&tmp_next_block_ctx);
745 kfree(selected_super);
746 return -1;
747 }
748
749 ret = btrfsic_process_metablock(state,
750 next_block,
751 &tmp_next_block_ctx,
752 BTRFS_MAX_LEVEL + 3, 1);
753 btrfsic_release_block_ctx(&tmp_next_block_ctx);
754 }
755 }
756
757 kfree(selected_super);
758 return ret;
759}
760
761static int btrfsic_process_superblock_dev_mirror(
762 struct btrfsic_state *state,
763 struct btrfsic_dev_state *dev_state,
764 struct btrfs_device *device,
765 int superblock_mirror_num,
766 struct btrfsic_dev_state **selected_dev_state,
767 struct btrfs_super_block *selected_super)
768{
769 struct btrfs_fs_info *fs_info = state->fs_info;
770 struct btrfs_super_block *super_tmp;
771 u64 dev_bytenr;
772 struct buffer_head *bh;
773 struct btrfsic_block *superblock_tmp;
774 int pass;
775 struct block_device *const superblock_bdev = device->bdev;
776
777 /* super block bytenr is always the unmapped device bytenr */
778 dev_bytenr = btrfs_sb_offset(superblock_mirror_num);
779 if (dev_bytenr + BTRFS_SUPER_INFO_SIZE > device->commit_total_bytes)
780 return -1;
781 bh = __bread(superblock_bdev, dev_bytenr / BTRFS_BDEV_BLOCKSIZE,
782 BTRFS_SUPER_INFO_SIZE);
783 if (NULL == bh)
784 return -1;
785 super_tmp = (struct btrfs_super_block *)
786 (bh->b_data + (dev_bytenr & (BTRFS_BDEV_BLOCKSIZE - 1)));
787
788 if (btrfs_super_bytenr(super_tmp) != dev_bytenr ||
789 btrfs_super_magic(super_tmp) != BTRFS_MAGIC ||
790 memcmp(device->uuid, super_tmp->dev_item.uuid, BTRFS_UUID_SIZE) ||
791 btrfs_super_nodesize(super_tmp) != state->metablock_size ||
792 btrfs_super_sectorsize(super_tmp) != state->datablock_size) {
793 brelse(bh);
794 return 0;
795 }
796
797 superblock_tmp =
798 btrfsic_block_hashtable_lookup(superblock_bdev,
799 dev_bytenr,
800 &state->block_hashtable);
801 if (NULL == superblock_tmp) {
802 superblock_tmp = btrfsic_block_alloc();
803 if (NULL == superblock_tmp) {
804 pr_info("btrfsic: error, kmalloc failed!\n");
805 brelse(bh);
806 return -1;
807 }
808 /* for superblock, only the dev_bytenr makes sense */
809 superblock_tmp->dev_bytenr = dev_bytenr;
810 superblock_tmp->dev_state = dev_state;
811 superblock_tmp->logical_bytenr = dev_bytenr;
812 superblock_tmp->generation = btrfs_super_generation(super_tmp);
813 superblock_tmp->is_metadata = 1;
814 superblock_tmp->is_superblock = 1;
815 superblock_tmp->is_iodone = 1;
816 superblock_tmp->never_written = 0;
817 superblock_tmp->mirror_num = 1 + superblock_mirror_num;
818 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
819 btrfs_info_in_rcu(fs_info,
820 "new initial S-block (bdev %p, %s) @%llu (%s/%llu/%d)",
821 superblock_bdev,
822 rcu_str_deref(device->name), dev_bytenr,
823 dev_state->name, dev_bytenr,
824 superblock_mirror_num);
825 list_add(&superblock_tmp->all_blocks_node,
826 &state->all_blocks_list);
827 btrfsic_block_hashtable_add(superblock_tmp,
828 &state->block_hashtable);
829 }
830
831 /* select the one with the highest generation field */
832 if (btrfs_super_generation(super_tmp) >
833 state->max_superblock_generation ||
834 0 == state->max_superblock_generation) {
835 memcpy(selected_super, super_tmp, sizeof(*selected_super));
836 *selected_dev_state = dev_state;
837 state->max_superblock_generation =
838 btrfs_super_generation(super_tmp);
839 state->latest_superblock = superblock_tmp;
840 }
841
842 for (pass = 0; pass < 3; pass++) {
843 u64 next_bytenr;
844 int num_copies;
845 int mirror_num;
846 const char *additional_string = NULL;
847 struct btrfs_disk_key tmp_disk_key;
848
849 tmp_disk_key.type = BTRFS_ROOT_ITEM_KEY;
850 tmp_disk_key.offset = 0;
851 switch (pass) {
852 case 0:
853 btrfs_set_disk_key_objectid(&tmp_disk_key,
854 BTRFS_ROOT_TREE_OBJECTID);
855 additional_string = "initial root ";
856 next_bytenr = btrfs_super_root(super_tmp);
857 break;
858 case 1:
859 btrfs_set_disk_key_objectid(&tmp_disk_key,
860 BTRFS_CHUNK_TREE_OBJECTID);
861 additional_string = "initial chunk ";
862 next_bytenr = btrfs_super_chunk_root(super_tmp);
863 break;
864 case 2:
865 btrfs_set_disk_key_objectid(&tmp_disk_key,
866 BTRFS_TREE_LOG_OBJECTID);
867 additional_string = "initial log ";
868 next_bytenr = btrfs_super_log_root(super_tmp);
869 if (0 == next_bytenr)
870 continue;
871 break;
872 }
873
874 num_copies = btrfs_num_copies(fs_info, next_bytenr,
875 state->metablock_size);
876 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
877 pr_info("num_copies(log_bytenr=%llu) = %d\n",
878 next_bytenr, num_copies);
879 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
880 struct btrfsic_block *next_block;
881 struct btrfsic_block_data_ctx tmp_next_block_ctx;
882 struct btrfsic_block_link *l;
883
884 if (btrfsic_map_block(state, next_bytenr,
885 state->metablock_size,
886 &tmp_next_block_ctx,
887 mirror_num)) {
888 pr_info("btrfsic: btrfsic_map_block(bytenr @%llu, mirror %d) failed!\n",
889 next_bytenr, mirror_num);
890 brelse(bh);
891 return -1;
892 }
893
894 next_block = btrfsic_block_lookup_or_add(
895 state, &tmp_next_block_ctx,
896 additional_string, 1, 1, 0,
897 mirror_num, NULL);
898 if (NULL == next_block) {
899 btrfsic_release_block_ctx(&tmp_next_block_ctx);
900 brelse(bh);
901 return -1;
902 }
903
904 next_block->disk_key = tmp_disk_key;
905 next_block->generation = BTRFSIC_GENERATION_UNKNOWN;
906 l = btrfsic_block_link_lookup_or_add(
907 state, &tmp_next_block_ctx,
908 next_block, superblock_tmp,
909 BTRFSIC_GENERATION_UNKNOWN);
910 btrfsic_release_block_ctx(&tmp_next_block_ctx);
911 if (NULL == l) {
912 brelse(bh);
913 return -1;
914 }
915 }
916 }
917 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_ALL_TREES)
918 btrfsic_dump_tree_sub(state, superblock_tmp, 0);
919
920 brelse(bh);
921 return 0;
922}
923
924static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void)
925{
926 struct btrfsic_stack_frame *sf;
927
928 sf = kzalloc(sizeof(*sf), GFP_NOFS);
929 if (NULL == sf)
930 pr_info("btrfsic: alloc memory failed!\n");
931 else
932 sf->magic = BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER;
933 return sf;
934}
935
936static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf)
937{
938 BUG_ON(!(NULL == sf ||
939 BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER == sf->magic));
940 kfree(sf);
941}
942
943static int btrfsic_process_metablock(
944 struct btrfsic_state *state,
945 struct btrfsic_block *const first_block,
946 struct btrfsic_block_data_ctx *const first_block_ctx,
947 int first_limit_nesting, int force_iodone_flag)
948{
949 struct btrfsic_stack_frame initial_stack_frame = { 0 };
950 struct btrfsic_stack_frame *sf;
951 struct btrfsic_stack_frame *next_stack;
952 struct btrfs_header *const first_hdr =
953 (struct btrfs_header *)first_block_ctx->datav[0];
954
955 BUG_ON(!first_hdr);
956 sf = &initial_stack_frame;
957 sf->error = 0;
958 sf->i = -1;
959 sf->limit_nesting = first_limit_nesting;
960 sf->block = first_block;
961 sf->block_ctx = first_block_ctx;
962 sf->next_block = NULL;
963 sf->hdr = first_hdr;
964 sf->prev = NULL;
965
966continue_with_new_stack_frame:
967 sf->block->generation = le64_to_cpu(sf->hdr->generation);
968 if (0 == sf->hdr->level) {
969 struct btrfs_leaf *const leafhdr =
970 (struct btrfs_leaf *)sf->hdr;
971
972 if (-1 == sf->i) {
973 sf->nr = btrfs_stack_header_nritems(&leafhdr->header);
974
975 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
976 pr_info("leaf %llu items %d generation %llu owner %llu\n",
977 sf->block_ctx->start, sf->nr,
978 btrfs_stack_header_generation(
979 &leafhdr->header),
980 btrfs_stack_header_owner(
981 &leafhdr->header));
982 }
983
984continue_with_current_leaf_stack_frame:
985 if (0 == sf->num_copies || sf->mirror_num > sf->num_copies) {
986 sf->i++;
987 sf->num_copies = 0;
988 }
989
990 if (sf->i < sf->nr) {
991 struct btrfs_item disk_item;
992 u32 disk_item_offset =
993 (uintptr_t)(leafhdr->items + sf->i) -
994 (uintptr_t)leafhdr;
995 struct btrfs_disk_key *disk_key;
996 u8 type;
997 u32 item_offset;
998 u32 item_size;
999
1000 if (disk_item_offset + sizeof(struct btrfs_item) >
1001 sf->block_ctx->len) {
1002leaf_item_out_of_bounce_error:
1003 pr_info("btrfsic: leaf item out of bounce at logical %llu, dev %s\n",
1004 sf->block_ctx->start,
1005 sf->block_ctx->dev->name);
1006 goto one_stack_frame_backwards;
1007 }
1008 btrfsic_read_from_block_data(sf->block_ctx,
1009 &disk_item,
1010 disk_item_offset,
1011 sizeof(struct btrfs_item));
1012 item_offset = btrfs_stack_item_offset(&disk_item);
1013 item_size = btrfs_stack_item_size(&disk_item);
1014 disk_key = &disk_item.key;
1015 type = btrfs_disk_key_type(disk_key);
1016
1017 if (BTRFS_ROOT_ITEM_KEY == type) {
1018 struct btrfs_root_item root_item;
1019 u32 root_item_offset;
1020 u64 next_bytenr;
1021
1022 root_item_offset = item_offset +
1023 offsetof(struct btrfs_leaf, items);
1024 if (root_item_offset + item_size >
1025 sf->block_ctx->len)
1026 goto leaf_item_out_of_bounce_error;
1027 btrfsic_read_from_block_data(
1028 sf->block_ctx, &root_item,
1029 root_item_offset,
1030 item_size);
1031 next_bytenr = btrfs_root_bytenr(&root_item);
1032
1033 sf->error =
1034 btrfsic_create_link_to_next_block(
1035 state,
1036 sf->block,
1037 sf->block_ctx,
1038 next_bytenr,
1039 sf->limit_nesting,
1040 &sf->next_block_ctx,
1041 &sf->next_block,
1042 force_iodone_flag,
1043 &sf->num_copies,
1044 &sf->mirror_num,
1045 disk_key,
1046 btrfs_root_generation(
1047 &root_item));
1048 if (sf->error)
1049 goto one_stack_frame_backwards;
1050
1051 if (NULL != sf->next_block) {
1052 struct btrfs_header *const next_hdr =
1053 (struct btrfs_header *)
1054 sf->next_block_ctx.datav[0];
1055
1056 next_stack =
1057 btrfsic_stack_frame_alloc();
1058 if (NULL == next_stack) {
1059 sf->error = -1;
1060 btrfsic_release_block_ctx(
1061 &sf->
1062 next_block_ctx);
1063 goto one_stack_frame_backwards;
1064 }
1065
1066 next_stack->i = -1;
1067 next_stack->block = sf->next_block;
1068 next_stack->block_ctx =
1069 &sf->next_block_ctx;
1070 next_stack->next_block = NULL;
1071 next_stack->hdr = next_hdr;
1072 next_stack->limit_nesting =
1073 sf->limit_nesting - 1;
1074 next_stack->prev = sf;
1075 sf = next_stack;
1076 goto continue_with_new_stack_frame;
1077 }
1078 } else if (BTRFS_EXTENT_DATA_KEY == type &&
1079 state->include_extent_data) {
1080 sf->error = btrfsic_handle_extent_data(
1081 state,
1082 sf->block,
1083 sf->block_ctx,
1084 item_offset,
1085 force_iodone_flag);
1086 if (sf->error)
1087 goto one_stack_frame_backwards;
1088 }
1089
1090 goto continue_with_current_leaf_stack_frame;
1091 }
1092 } else {
1093 struct btrfs_node *const nodehdr = (struct btrfs_node *)sf->hdr;
1094
1095 if (-1 == sf->i) {
1096 sf->nr = btrfs_stack_header_nritems(&nodehdr->header);
1097
1098 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1099 pr_info("node %llu level %d items %d generation %llu owner %llu\n",
1100 sf->block_ctx->start,
1101 nodehdr->header.level, sf->nr,
1102 btrfs_stack_header_generation(
1103 &nodehdr->header),
1104 btrfs_stack_header_owner(
1105 &nodehdr->header));
1106 }
1107
1108continue_with_current_node_stack_frame:
1109 if (0 == sf->num_copies || sf->mirror_num > sf->num_copies) {
1110 sf->i++;
1111 sf->num_copies = 0;
1112 }
1113
1114 if (sf->i < sf->nr) {
1115 struct btrfs_key_ptr key_ptr;
1116 u32 key_ptr_offset;
1117 u64 next_bytenr;
1118
1119 key_ptr_offset = (uintptr_t)(nodehdr->ptrs + sf->i) -
1120 (uintptr_t)nodehdr;
1121 if (key_ptr_offset + sizeof(struct btrfs_key_ptr) >
1122 sf->block_ctx->len) {
1123 pr_info("btrfsic: node item out of bounce at logical %llu, dev %s\n",
1124 sf->block_ctx->start,
1125 sf->block_ctx->dev->name);
1126 goto one_stack_frame_backwards;
1127 }
1128 btrfsic_read_from_block_data(
1129 sf->block_ctx, &key_ptr, key_ptr_offset,
1130 sizeof(struct btrfs_key_ptr));
1131 next_bytenr = btrfs_stack_key_blockptr(&key_ptr);
1132
1133 sf->error = btrfsic_create_link_to_next_block(
1134 state,
1135 sf->block,
1136 sf->block_ctx,
1137 next_bytenr,
1138 sf->limit_nesting,
1139 &sf->next_block_ctx,
1140 &sf->next_block,
1141 force_iodone_flag,
1142 &sf->num_copies,
1143 &sf->mirror_num,
1144 &key_ptr.key,
1145 btrfs_stack_key_generation(&key_ptr));
1146 if (sf->error)
1147 goto one_stack_frame_backwards;
1148
1149 if (NULL != sf->next_block) {
1150 struct btrfs_header *const next_hdr =
1151 (struct btrfs_header *)
1152 sf->next_block_ctx.datav[0];
1153
1154 next_stack = btrfsic_stack_frame_alloc();
1155 if (NULL == next_stack) {
1156 sf->error = -1;
1157 goto one_stack_frame_backwards;
1158 }
1159
1160 next_stack->i = -1;
1161 next_stack->block = sf->next_block;
1162 next_stack->block_ctx = &sf->next_block_ctx;
1163 next_stack->next_block = NULL;
1164 next_stack->hdr = next_hdr;
1165 next_stack->limit_nesting =
1166 sf->limit_nesting - 1;
1167 next_stack->prev = sf;
1168 sf = next_stack;
1169 goto continue_with_new_stack_frame;
1170 }
1171
1172 goto continue_with_current_node_stack_frame;
1173 }
1174 }
1175
1176one_stack_frame_backwards:
1177 if (NULL != sf->prev) {
1178 struct btrfsic_stack_frame *const prev = sf->prev;
1179
1180 /* the one for the initial block is freed in the caller */
1181 btrfsic_release_block_ctx(sf->block_ctx);
1182
1183 if (sf->error) {
1184 prev->error = sf->error;
1185 btrfsic_stack_frame_free(sf);
1186 sf = prev;
1187 goto one_stack_frame_backwards;
1188 }
1189
1190 btrfsic_stack_frame_free(sf);
1191 sf = prev;
1192 goto continue_with_new_stack_frame;
1193 } else {
1194 BUG_ON(&initial_stack_frame != sf);
1195 }
1196
1197 return sf->error;
1198}
1199
1200static void btrfsic_read_from_block_data(
1201 struct btrfsic_block_data_ctx *block_ctx,
1202 void *dstv, u32 offset, size_t len)
1203{
1204 size_t cur;
1205 size_t offset_in_page;
1206 char *kaddr;
1207 char *dst = (char *)dstv;
1208 size_t start_offset = block_ctx->start & ((u64)PAGE_SIZE - 1);
1209 unsigned long i = (start_offset + offset) >> PAGE_SHIFT;
1210
1211 WARN_ON(offset + len > block_ctx->len);
1212 offset_in_page = (start_offset + offset) & (PAGE_SIZE - 1);
1213
1214 while (len > 0) {
1215 cur = min(len, ((size_t)PAGE_SIZE - offset_in_page));
1216 BUG_ON(i >= DIV_ROUND_UP(block_ctx->len, PAGE_SIZE));
1217 kaddr = block_ctx->datav[i];
1218 memcpy(dst, kaddr + offset_in_page, cur);
1219
1220 dst += cur;
1221 len -= cur;
1222 offset_in_page = 0;
1223 i++;
1224 }
1225}
1226
1227static int btrfsic_create_link_to_next_block(
1228 struct btrfsic_state *state,
1229 struct btrfsic_block *block,
1230 struct btrfsic_block_data_ctx *block_ctx,
1231 u64 next_bytenr,
1232 int limit_nesting,
1233 struct btrfsic_block_data_ctx *next_block_ctx,
1234 struct btrfsic_block **next_blockp,
1235 int force_iodone_flag,
1236 int *num_copiesp, int *mirror_nump,
1237 struct btrfs_disk_key *disk_key,
1238 u64 parent_generation)
1239{
1240 struct btrfs_fs_info *fs_info = state->fs_info;
1241 struct btrfsic_block *next_block = NULL;
1242 int ret;
1243 struct btrfsic_block_link *l;
1244 int did_alloc_block_link;
1245 int block_was_created;
1246
1247 *next_blockp = NULL;
1248 if (0 == *num_copiesp) {
1249 *num_copiesp = btrfs_num_copies(fs_info, next_bytenr,
1250 state->metablock_size);
1251 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
1252 pr_info("num_copies(log_bytenr=%llu) = %d\n",
1253 next_bytenr, *num_copiesp);
1254 *mirror_nump = 1;
1255 }
1256
1257 if (*mirror_nump > *num_copiesp)
1258 return 0;
1259
1260 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1261 pr_info("btrfsic_create_link_to_next_block(mirror_num=%d)\n",
1262 *mirror_nump);
1263 ret = btrfsic_map_block(state, next_bytenr,
1264 state->metablock_size,
1265 next_block_ctx, *mirror_nump);
1266 if (ret) {
1267 pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n",
1268 next_bytenr, *mirror_nump);
1269 btrfsic_release_block_ctx(next_block_ctx);
1270 *next_blockp = NULL;
1271 return -1;
1272 }
1273
1274 next_block = btrfsic_block_lookup_or_add(state,
1275 next_block_ctx, "referenced ",
1276 1, force_iodone_flag,
1277 !force_iodone_flag,
1278 *mirror_nump,
1279 &block_was_created);
1280 if (NULL == next_block) {
1281 btrfsic_release_block_ctx(next_block_ctx);
1282 *next_blockp = NULL;
1283 return -1;
1284 }
1285 if (block_was_created) {
1286 l = NULL;
1287 next_block->generation = BTRFSIC_GENERATION_UNKNOWN;
1288 } else {
1289 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) {
1290 if (next_block->logical_bytenr != next_bytenr &&
1291 !(!next_block->is_metadata &&
1292 0 == next_block->logical_bytenr))
1293 pr_info("Referenced block @%llu (%s/%llu/%d) found in hash table, %c, bytenr mismatch (!= stored %llu).\n",
1294 next_bytenr, next_block_ctx->dev->name,
1295 next_block_ctx->dev_bytenr, *mirror_nump,
1296 btrfsic_get_block_type(state,
1297 next_block),
1298 next_block->logical_bytenr);
1299 else
1300 pr_info("Referenced block @%llu (%s/%llu/%d) found in hash table, %c.\n",
1301 next_bytenr, next_block_ctx->dev->name,
1302 next_block_ctx->dev_bytenr, *mirror_nump,
1303 btrfsic_get_block_type(state,
1304 next_block));
1305 }
1306 next_block->logical_bytenr = next_bytenr;
1307
1308 next_block->mirror_num = *mirror_nump;
1309 l = btrfsic_block_link_hashtable_lookup(
1310 next_block_ctx->dev->bdev,
1311 next_block_ctx->dev_bytenr,
1312 block_ctx->dev->bdev,
1313 block_ctx->dev_bytenr,
1314 &state->block_link_hashtable);
1315 }
1316
1317 next_block->disk_key = *disk_key;
1318 if (NULL == l) {
1319 l = btrfsic_block_link_alloc();
1320 if (NULL == l) {
1321 pr_info("btrfsic: error, kmalloc failed!\n");
1322 btrfsic_release_block_ctx(next_block_ctx);
1323 *next_blockp = NULL;
1324 return -1;
1325 }
1326
1327 did_alloc_block_link = 1;
1328 l->block_ref_to = next_block;
1329 l->block_ref_from = block;
1330 l->ref_cnt = 1;
1331 l->parent_generation = parent_generation;
1332
1333 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1334 btrfsic_print_add_link(state, l);
1335
1336 list_add(&l->node_ref_to, &block->ref_to_list);
1337 list_add(&l->node_ref_from, &next_block->ref_from_list);
1338
1339 btrfsic_block_link_hashtable_add(l,
1340 &state->block_link_hashtable);
1341 } else {
1342 did_alloc_block_link = 0;
1343 if (0 == limit_nesting) {
1344 l->ref_cnt++;
1345 l->parent_generation = parent_generation;
1346 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1347 btrfsic_print_add_link(state, l);
1348 }
1349 }
1350
1351 if (limit_nesting > 0 && did_alloc_block_link) {
1352 ret = btrfsic_read_block(state, next_block_ctx);
1353 if (ret < (int)next_block_ctx->len) {
1354 pr_info("btrfsic: read block @logical %llu failed!\n",
1355 next_bytenr);
1356 btrfsic_release_block_ctx(next_block_ctx);
1357 *next_blockp = NULL;
1358 return -1;
1359 }
1360
1361 *next_blockp = next_block;
1362 } else {
1363 *next_blockp = NULL;
1364 }
1365 (*mirror_nump)++;
1366
1367 return 0;
1368}
1369
1370static int btrfsic_handle_extent_data(
1371 struct btrfsic_state *state,
1372 struct btrfsic_block *block,
1373 struct btrfsic_block_data_ctx *block_ctx,
1374 u32 item_offset, int force_iodone_flag)
1375{
1376 struct btrfs_fs_info *fs_info = state->fs_info;
1377 struct btrfs_file_extent_item file_extent_item;
1378 u64 file_extent_item_offset;
1379 u64 next_bytenr;
1380 u64 num_bytes;
1381 u64 generation;
1382 struct btrfsic_block_link *l;
1383 int ret;
1384
1385 file_extent_item_offset = offsetof(struct btrfs_leaf, items) +
1386 item_offset;
1387 if (file_extent_item_offset +
1388 offsetof(struct btrfs_file_extent_item, disk_num_bytes) >
1389 block_ctx->len) {
1390 pr_info("btrfsic: file item out of bounce at logical %llu, dev %s\n",
1391 block_ctx->start, block_ctx->dev->name);
1392 return -1;
1393 }
1394
1395 btrfsic_read_from_block_data(block_ctx, &file_extent_item,
1396 file_extent_item_offset,
1397 offsetof(struct btrfs_file_extent_item, disk_num_bytes));
1398 if (BTRFS_FILE_EXTENT_REG != file_extent_item.type ||
1399 btrfs_stack_file_extent_disk_bytenr(&file_extent_item) == 0) {
1400 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE)
1401 pr_info("extent_data: type %u, disk_bytenr = %llu\n",
1402 file_extent_item.type,
1403 btrfs_stack_file_extent_disk_bytenr(
1404 &file_extent_item));
1405 return 0;
1406 }
1407
1408 if (file_extent_item_offset + sizeof(struct btrfs_file_extent_item) >
1409 block_ctx->len) {
1410 pr_info("btrfsic: file item out of bounce at logical %llu, dev %s\n",
1411 block_ctx->start, block_ctx->dev->name);
1412 return -1;
1413 }
1414 btrfsic_read_from_block_data(block_ctx, &file_extent_item,
1415 file_extent_item_offset,
1416 sizeof(struct btrfs_file_extent_item));
1417 next_bytenr = btrfs_stack_file_extent_disk_bytenr(&file_extent_item);
1418 if (btrfs_stack_file_extent_compression(&file_extent_item) ==
1419 BTRFS_COMPRESS_NONE) {
1420 next_bytenr += btrfs_stack_file_extent_offset(&file_extent_item);
1421 num_bytes = btrfs_stack_file_extent_num_bytes(&file_extent_item);
1422 } else {
1423 num_bytes = btrfs_stack_file_extent_disk_num_bytes(&file_extent_item);
1424 }
1425 generation = btrfs_stack_file_extent_generation(&file_extent_item);
1426
1427 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE)
1428 pr_info("extent_data: type %u, disk_bytenr = %llu, offset = %llu, num_bytes = %llu\n",
1429 file_extent_item.type,
1430 btrfs_stack_file_extent_disk_bytenr(&file_extent_item),
1431 btrfs_stack_file_extent_offset(&file_extent_item),
1432 num_bytes);
1433 while (num_bytes > 0) {
1434 u32 chunk_len;
1435 int num_copies;
1436 int mirror_num;
1437
1438 if (num_bytes > state->datablock_size)
1439 chunk_len = state->datablock_size;
1440 else
1441 chunk_len = num_bytes;
1442
1443 num_copies = btrfs_num_copies(fs_info, next_bytenr,
1444 state->datablock_size);
1445 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
1446 pr_info("num_copies(log_bytenr=%llu) = %d\n",
1447 next_bytenr, num_copies);
1448 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
1449 struct btrfsic_block_data_ctx next_block_ctx;
1450 struct btrfsic_block *next_block;
1451 int block_was_created;
1452
1453 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1454 pr_info("btrfsic_handle_extent_data(mirror_num=%d)\n",
1455 mirror_num);
1456 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE)
1457 pr_info("\tdisk_bytenr = %llu, num_bytes %u\n",
1458 next_bytenr, chunk_len);
1459 ret = btrfsic_map_block(state, next_bytenr,
1460 chunk_len, &next_block_ctx,
1461 mirror_num);
1462 if (ret) {
1463 pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n",
1464 next_bytenr, mirror_num);
1465 return -1;
1466 }
1467
1468 next_block = btrfsic_block_lookup_or_add(
1469 state,
1470 &next_block_ctx,
1471 "referenced ",
1472 0,
1473 force_iodone_flag,
1474 !force_iodone_flag,
1475 mirror_num,
1476 &block_was_created);
1477 if (NULL == next_block) {
1478 pr_info("btrfsic: error, kmalloc failed!\n");
1479 btrfsic_release_block_ctx(&next_block_ctx);
1480 return -1;
1481 }
1482 if (!block_was_created) {
1483 if ((state->print_mask &
1484 BTRFSIC_PRINT_MASK_VERBOSE) &&
1485 next_block->logical_bytenr != next_bytenr &&
1486 !(!next_block->is_metadata &&
1487 0 == next_block->logical_bytenr)) {
1488 pr_info("Referenced block @%llu (%s/%llu/%d) found in hash table, D, bytenr mismatch (!= stored %llu).\n",
1489 next_bytenr,
1490 next_block_ctx.dev->name,
1491 next_block_ctx.dev_bytenr,
1492 mirror_num,
1493 next_block->logical_bytenr);
1494 }
1495 next_block->logical_bytenr = next_bytenr;
1496 next_block->mirror_num = mirror_num;
1497 }
1498
1499 l = btrfsic_block_link_lookup_or_add(state,
1500 &next_block_ctx,
1501 next_block, block,
1502 generation);
1503 btrfsic_release_block_ctx(&next_block_ctx);
1504 if (NULL == l)
1505 return -1;
1506 }
1507
1508 next_bytenr += chunk_len;
1509 num_bytes -= chunk_len;
1510 }
1511
1512 return 0;
1513}
1514
1515static int btrfsic_map_block(struct btrfsic_state *state, u64 bytenr, u32 len,
1516 struct btrfsic_block_data_ctx *block_ctx_out,
1517 int mirror_num)
1518{
1519 struct btrfs_fs_info *fs_info = state->fs_info;
1520 int ret;
1521 u64 length;
1522 struct btrfs_bio *multi = NULL;
1523 struct btrfs_device *device;
1524
1525 length = len;
1526 ret = btrfs_map_block(fs_info, BTRFS_MAP_READ,
1527 bytenr, &length, &multi, mirror_num);
1528
1529 if (ret) {
1530 block_ctx_out->start = 0;
1531 block_ctx_out->dev_bytenr = 0;
1532 block_ctx_out->len = 0;
1533 block_ctx_out->dev = NULL;
1534 block_ctx_out->datav = NULL;
1535 block_ctx_out->pagev = NULL;
1536 block_ctx_out->mem_to_free = NULL;
1537
1538 return ret;
1539 }
1540
1541 device = multi->stripes[0].dev;
1542 block_ctx_out->dev = btrfsic_dev_state_lookup(device->bdev->bd_dev);
1543 block_ctx_out->dev_bytenr = multi->stripes[0].physical;
1544 block_ctx_out->start = bytenr;
1545 block_ctx_out->len = len;
1546 block_ctx_out->datav = NULL;
1547 block_ctx_out->pagev = NULL;
1548 block_ctx_out->mem_to_free = NULL;
1549
1550 kfree(multi);
1551 if (NULL == block_ctx_out->dev) {
1552 ret = -ENXIO;
1553 pr_info("btrfsic: error, cannot lookup dev (#1)!\n");
1554 }
1555
1556 return ret;
1557}
1558
1559static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx)
1560{
1561 if (block_ctx->mem_to_free) {
1562 unsigned int num_pages;
1563
1564 BUG_ON(!block_ctx->datav);
1565 BUG_ON(!block_ctx->pagev);
1566 num_pages = (block_ctx->len + (u64)PAGE_SIZE - 1) >>
1567 PAGE_SHIFT;
1568 while (num_pages > 0) {
1569 num_pages--;
1570 if (block_ctx->datav[num_pages]) {
1571 kunmap(block_ctx->pagev[num_pages]);
1572 block_ctx->datav[num_pages] = NULL;
1573 }
1574 if (block_ctx->pagev[num_pages]) {
1575 __free_page(block_ctx->pagev[num_pages]);
1576 block_ctx->pagev[num_pages] = NULL;
1577 }
1578 }
1579
1580 kfree(block_ctx->mem_to_free);
1581 block_ctx->mem_to_free = NULL;
1582 block_ctx->pagev = NULL;
1583 block_ctx->datav = NULL;
1584 }
1585}
1586
1587static int btrfsic_read_block(struct btrfsic_state *state,
1588 struct btrfsic_block_data_ctx *block_ctx)
1589{
1590 unsigned int num_pages;
1591 unsigned int i;
1592 u64 dev_bytenr;
1593 int ret;
1594
1595 BUG_ON(block_ctx->datav);
1596 BUG_ON(block_ctx->pagev);
1597 BUG_ON(block_ctx->mem_to_free);
1598 if (block_ctx->dev_bytenr & ((u64)PAGE_SIZE - 1)) {
1599 pr_info("btrfsic: read_block() with unaligned bytenr %llu\n",
1600 block_ctx->dev_bytenr);
1601 return -1;
1602 }
1603
1604 num_pages = (block_ctx->len + (u64)PAGE_SIZE - 1) >>
1605 PAGE_SHIFT;
1606 block_ctx->mem_to_free = kzalloc((sizeof(*block_ctx->datav) +
1607 sizeof(*block_ctx->pagev)) *
1608 num_pages, GFP_NOFS);
1609 if (!block_ctx->mem_to_free)
1610 return -ENOMEM;
1611 block_ctx->datav = block_ctx->mem_to_free;
1612 block_ctx->pagev = (struct page **)(block_ctx->datav + num_pages);
1613 for (i = 0; i < num_pages; i++) {
1614 block_ctx->pagev[i] = alloc_page(GFP_NOFS);
1615 if (!block_ctx->pagev[i])
1616 return -1;
1617 }
1618
1619 dev_bytenr = block_ctx->dev_bytenr;
1620 for (i = 0; i < num_pages;) {
1621 struct bio *bio;
1622 unsigned int j;
1623
1624 bio = btrfs_io_bio_alloc(num_pages - i);
1625 bio_set_dev(bio, block_ctx->dev->bdev);
1626 bio->bi_iter.bi_sector = dev_bytenr >> 9;
1627 bio_set_op_attrs(bio, REQ_OP_READ, 0);
1628
1629 for (j = i; j < num_pages; j++) {
1630 ret = bio_add_page(bio, block_ctx->pagev[j],
1631 PAGE_SIZE, 0);
1632 if (PAGE_SIZE != ret)
1633 break;
1634 }
1635 if (j == i) {
1636 pr_info("btrfsic: error, failed to add a single page!\n");
1637 return -1;
1638 }
1639 if (submit_bio_wait(bio)) {
1640 pr_info("btrfsic: read error at logical %llu dev %s!\n",
1641 block_ctx->start, block_ctx->dev->name);
1642 bio_put(bio);
1643 return -1;
1644 }
1645 bio_put(bio);
1646 dev_bytenr += (j - i) * PAGE_SIZE;
1647 i = j;
1648 }
1649 for (i = 0; i < num_pages; i++)
1650 block_ctx->datav[i] = kmap(block_ctx->pagev[i]);
1651
1652 return block_ctx->len;
1653}
1654
1655static void btrfsic_dump_database(struct btrfsic_state *state)
1656{
1657 const struct btrfsic_block *b_all;
1658
1659 BUG_ON(NULL == state);
1660
1661 pr_info("all_blocks_list:\n");
1662 list_for_each_entry(b_all, &state->all_blocks_list, all_blocks_node) {
1663 const struct btrfsic_block_link *l;
1664
1665 pr_info("%c-block @%llu (%s/%llu/%d)\n",
1666 btrfsic_get_block_type(state, b_all),
1667 b_all->logical_bytenr, b_all->dev_state->name,
1668 b_all->dev_bytenr, b_all->mirror_num);
1669
1670 list_for_each_entry(l, &b_all->ref_to_list, node_ref_to) {
1671 pr_info(" %c @%llu (%s/%llu/%d) refers %u* to %c @%llu (%s/%llu/%d)\n",
1672 btrfsic_get_block_type(state, b_all),
1673 b_all->logical_bytenr, b_all->dev_state->name,
1674 b_all->dev_bytenr, b_all->mirror_num,
1675 l->ref_cnt,
1676 btrfsic_get_block_type(state, l->block_ref_to),
1677 l->block_ref_to->logical_bytenr,
1678 l->block_ref_to->dev_state->name,
1679 l->block_ref_to->dev_bytenr,
1680 l->block_ref_to->mirror_num);
1681 }
1682
1683 list_for_each_entry(l, &b_all->ref_from_list, node_ref_from) {
1684 pr_info(" %c @%llu (%s/%llu/%d) is ref %u* from %c @%llu (%s/%llu/%d)\n",
1685 btrfsic_get_block_type(state, b_all),
1686 b_all->logical_bytenr, b_all->dev_state->name,
1687 b_all->dev_bytenr, b_all->mirror_num,
1688 l->ref_cnt,
1689 btrfsic_get_block_type(state, l->block_ref_from),
1690 l->block_ref_from->logical_bytenr,
1691 l->block_ref_from->dev_state->name,
1692 l->block_ref_from->dev_bytenr,
1693 l->block_ref_from->mirror_num);
1694 }
1695
1696 pr_info("\n");
1697 }
1698}
1699
1700/*
1701 * Test whether the disk block contains a tree block (leaf or node)
1702 * (note that this test fails for the super block)
1703 */
1704static int btrfsic_test_for_metadata(struct btrfsic_state *state,
1705 char **datav, unsigned int num_pages)
1706{
1707 struct btrfs_fs_info *fs_info = state->fs_info;
1708 struct btrfs_header *h;
1709 u8 csum[BTRFS_CSUM_SIZE];
1710 u32 crc = ~(u32)0;
1711 unsigned int i;
1712
1713 if (num_pages * PAGE_SIZE < state->metablock_size)
1714 return 1; /* not metadata */
1715 num_pages = state->metablock_size >> PAGE_SHIFT;
1716 h = (struct btrfs_header *)datav[0];
1717
1718 if (memcmp(h->fsid, fs_info->fsid, BTRFS_FSID_SIZE))
1719 return 1;
1720
1721 for (i = 0; i < num_pages; i++) {
1722 u8 *data = i ? datav[i] : (datav[i] + BTRFS_CSUM_SIZE);
1723 size_t sublen = i ? PAGE_SIZE :
1724 (PAGE_SIZE - BTRFS_CSUM_SIZE);
1725
1726 crc = crc32c(crc, data, sublen);
1727 }
1728 btrfs_csum_final(crc, csum);
1729 if (memcmp(csum, h->csum, state->csum_size))
1730 return 1;
1731
1732 return 0; /* is metadata */
1733}
1734
1735static void btrfsic_process_written_block(struct btrfsic_dev_state *dev_state,
1736 u64 dev_bytenr, char **mapped_datav,
1737 unsigned int num_pages,
1738 struct bio *bio, int *bio_is_patched,
1739 struct buffer_head *bh,
1740 int submit_bio_bh_rw)
1741{
1742 int is_metadata;
1743 struct btrfsic_block *block;
1744 struct btrfsic_block_data_ctx block_ctx;
1745 int ret;
1746 struct btrfsic_state *state = dev_state->state;
1747 struct block_device *bdev = dev_state->bdev;
1748 unsigned int processed_len;
1749
1750 if (NULL != bio_is_patched)
1751 *bio_is_patched = 0;
1752
1753again:
1754 if (num_pages == 0)
1755 return;
1756
1757 processed_len = 0;
1758 is_metadata = (0 == btrfsic_test_for_metadata(state, mapped_datav,
1759 num_pages));
1760
1761 block = btrfsic_block_hashtable_lookup(bdev, dev_bytenr,
1762 &state->block_hashtable);
1763 if (NULL != block) {
1764 u64 bytenr = 0;
1765 struct btrfsic_block_link *l, *tmp;
1766
1767 if (block->is_superblock) {
1768 bytenr = btrfs_super_bytenr((struct btrfs_super_block *)
1769 mapped_datav[0]);
1770 if (num_pages * PAGE_SIZE <
1771 BTRFS_SUPER_INFO_SIZE) {
1772 pr_info("btrfsic: cannot work with too short bios!\n");
1773 return;
1774 }
1775 is_metadata = 1;
1776 BUG_ON(BTRFS_SUPER_INFO_SIZE & (PAGE_SIZE - 1));
1777 processed_len = BTRFS_SUPER_INFO_SIZE;
1778 if (state->print_mask &
1779 BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE) {
1780 pr_info("[before new superblock is written]:\n");
1781 btrfsic_dump_tree_sub(state, block, 0);
1782 }
1783 }
1784 if (is_metadata) {
1785 if (!block->is_superblock) {
1786 if (num_pages * PAGE_SIZE <
1787 state->metablock_size) {
1788 pr_info("btrfsic: cannot work with too short bios!\n");
1789 return;
1790 }
1791 processed_len = state->metablock_size;
1792 bytenr = btrfs_stack_header_bytenr(
1793 (struct btrfs_header *)
1794 mapped_datav[0]);
1795 btrfsic_cmp_log_and_dev_bytenr(state, bytenr,
1796 dev_state,
1797 dev_bytenr);
1798 }
1799 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) {
1800 if (block->logical_bytenr != bytenr &&
1801 !(!block->is_metadata &&
1802 block->logical_bytenr == 0))
1803 pr_info("Written block @%llu (%s/%llu/%d) found in hash table, %c, bytenr mismatch (!= stored %llu).\n",
1804 bytenr, dev_state->name,
1805 dev_bytenr,
1806 block->mirror_num,
1807 btrfsic_get_block_type(state,
1808 block),
1809 block->logical_bytenr);
1810 else
1811 pr_info("Written block @%llu (%s/%llu/%d) found in hash table, %c.\n",
1812 bytenr, dev_state->name,
1813 dev_bytenr, block->mirror_num,
1814 btrfsic_get_block_type(state,
1815 block));
1816 }
1817 block->logical_bytenr = bytenr;
1818 } else {
1819 if (num_pages * PAGE_SIZE <
1820 state->datablock_size) {
1821 pr_info("btrfsic: cannot work with too short bios!\n");
1822 return;
1823 }
1824 processed_len = state->datablock_size;
1825 bytenr = block->logical_bytenr;
1826 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1827 pr_info("Written block @%llu (%s/%llu/%d) found in hash table, %c.\n",
1828 bytenr, dev_state->name, dev_bytenr,
1829 block->mirror_num,
1830 btrfsic_get_block_type(state, block));
1831 }
1832
1833 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1834 pr_info("ref_to_list: %cE, ref_from_list: %cE\n",
1835 list_empty(&block->ref_to_list) ? ' ' : '!',
1836 list_empty(&block->ref_from_list) ? ' ' : '!');
1837 if (btrfsic_is_block_ref_by_superblock(state, block, 0)) {
1838 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",
1839 btrfsic_get_block_type(state, block), bytenr,
1840 dev_state->name, dev_bytenr, block->mirror_num,
1841 block->generation,
1842 btrfs_disk_key_objectid(&block->disk_key),
1843 block->disk_key.type,
1844 btrfs_disk_key_offset(&block->disk_key),
1845 btrfs_stack_header_generation(
1846 (struct btrfs_header *) mapped_datav[0]),
1847 state->max_superblock_generation);
1848 btrfsic_dump_tree(state);
1849 }
1850
1851 if (!block->is_iodone && !block->never_written) {
1852 pr_info("btrfs: attempt to overwrite %c-block @%llu (%s/%llu/%d), oldgen=%llu, newgen=%llu, which is not yet iodone!\n",
1853 btrfsic_get_block_type(state, block), bytenr,
1854 dev_state->name, dev_bytenr, block->mirror_num,
1855 block->generation,
1856 btrfs_stack_header_generation(
1857 (struct btrfs_header *)
1858 mapped_datav[0]));
1859 /* it would not be safe to go on */
1860 btrfsic_dump_tree(state);
1861 goto continue_loop;
1862 }
1863
1864 /*
1865 * Clear all references of this block. Do not free
1866 * the block itself even if is not referenced anymore
1867 * because it still carries valuable information
1868 * like whether it was ever written and IO completed.
1869 */
1870 list_for_each_entry_safe(l, tmp, &block->ref_to_list,
1871 node_ref_to) {
1872 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1873 btrfsic_print_rem_link(state, l);
1874 l->ref_cnt--;
1875 if (0 == l->ref_cnt) {
1876 list_del(&l->node_ref_to);
1877 list_del(&l->node_ref_from);
1878 btrfsic_block_link_hashtable_remove(l);
1879 btrfsic_block_link_free(l);
1880 }
1881 }
1882
1883 block_ctx.dev = dev_state;
1884 block_ctx.dev_bytenr = dev_bytenr;
1885 block_ctx.start = bytenr;
1886 block_ctx.len = processed_len;
1887 block_ctx.pagev = NULL;
1888 block_ctx.mem_to_free = NULL;
1889 block_ctx.datav = mapped_datav;
1890
1891 if (is_metadata || state->include_extent_data) {
1892 block->never_written = 0;
1893 block->iodone_w_error = 0;
1894 if (NULL != bio) {
1895 block->is_iodone = 0;
1896 BUG_ON(NULL == bio_is_patched);
1897 if (!*bio_is_patched) {
1898 block->orig_bio_bh_private =
1899 bio->bi_private;
1900 block->orig_bio_bh_end_io.bio =
1901 bio->bi_end_io;
1902 block->next_in_same_bio = NULL;
1903 bio->bi_private = block;
1904 bio->bi_end_io = btrfsic_bio_end_io;
1905 *bio_is_patched = 1;
1906 } else {
1907 struct btrfsic_block *chained_block =
1908 (struct btrfsic_block *)
1909 bio->bi_private;
1910
1911 BUG_ON(NULL == chained_block);
1912 block->orig_bio_bh_private =
1913 chained_block->orig_bio_bh_private;
1914 block->orig_bio_bh_end_io.bio =
1915 chained_block->orig_bio_bh_end_io.
1916 bio;
1917 block->next_in_same_bio = chained_block;
1918 bio->bi_private = block;
1919 }
1920 } else if (NULL != bh) {
1921 block->is_iodone = 0;
1922 block->orig_bio_bh_private = bh->b_private;
1923 block->orig_bio_bh_end_io.bh = bh->b_end_io;
1924 block->next_in_same_bio = NULL;
1925 bh->b_private = block;
1926 bh->b_end_io = btrfsic_bh_end_io;
1927 } else {
1928 block->is_iodone = 1;
1929 block->orig_bio_bh_private = NULL;
1930 block->orig_bio_bh_end_io.bio = NULL;
1931 block->next_in_same_bio = NULL;
1932 }
1933 }
1934
1935 block->flush_gen = dev_state->last_flush_gen + 1;
1936 block->submit_bio_bh_rw = submit_bio_bh_rw;
1937 if (is_metadata) {
1938 block->logical_bytenr = bytenr;
1939 block->is_metadata = 1;
1940 if (block->is_superblock) {
1941 BUG_ON(PAGE_SIZE !=
1942 BTRFS_SUPER_INFO_SIZE);
1943 ret = btrfsic_process_written_superblock(
1944 state,
1945 block,
1946 (struct btrfs_super_block *)
1947 mapped_datav[0]);
1948 if (state->print_mask &
1949 BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE) {
1950 pr_info("[after new superblock is written]:\n");
1951 btrfsic_dump_tree_sub(state, block, 0);
1952 }
1953 } else {
1954 block->mirror_num = 0; /* unknown */
1955 ret = btrfsic_process_metablock(
1956 state,
1957 block,
1958 &block_ctx,
1959 0, 0);
1960 }
1961 if (ret)
1962 pr_info("btrfsic: btrfsic_process_metablock(root @%llu) failed!\n",
1963 dev_bytenr);
1964 } else {
1965 block->is_metadata = 0;
1966 block->mirror_num = 0; /* unknown */
1967 block->generation = BTRFSIC_GENERATION_UNKNOWN;
1968 if (!state->include_extent_data
1969 && list_empty(&block->ref_from_list)) {
1970 /*
1971 * disk block is overwritten with extent
1972 * data (not meta data) and we are configured
1973 * to not include extent data: take the
1974 * chance and free the block's memory
1975 */
1976 btrfsic_block_hashtable_remove(block);
1977 list_del(&block->all_blocks_node);
1978 btrfsic_block_free(block);
1979 }
1980 }
1981 btrfsic_release_block_ctx(&block_ctx);
1982 } else {
1983 /* block has not been found in hash table */
1984 u64 bytenr;
1985
1986 if (!is_metadata) {
1987 processed_len = state->datablock_size;
1988 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1989 pr_info("Written block (%s/%llu/?) !found in hash table, D.\n",
1990 dev_state->name, dev_bytenr);
1991 if (!state->include_extent_data) {
1992 /* ignore that written D block */
1993 goto continue_loop;
1994 }
1995
1996 /* this is getting ugly for the
1997 * include_extent_data case... */
1998 bytenr = 0; /* unknown */
1999 } else {
2000 processed_len = state->metablock_size;
2001 bytenr = btrfs_stack_header_bytenr(
2002 (struct btrfs_header *)
2003 mapped_datav[0]);
2004 btrfsic_cmp_log_and_dev_bytenr(state, bytenr, dev_state,
2005 dev_bytenr);
2006 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2007 pr_info("Written block @%llu (%s/%llu/?) !found in hash table, M.\n",
2008 bytenr, dev_state->name, dev_bytenr);
2009 }
2010
2011 block_ctx.dev = dev_state;
2012 block_ctx.dev_bytenr = dev_bytenr;
2013 block_ctx.start = bytenr;
2014 block_ctx.len = processed_len;
2015 block_ctx.pagev = NULL;
2016 block_ctx.mem_to_free = NULL;
2017 block_ctx.datav = mapped_datav;
2018
2019 block = btrfsic_block_alloc();
2020 if (NULL == block) {
2021 pr_info("btrfsic: error, kmalloc failed!\n");
2022 btrfsic_release_block_ctx(&block_ctx);
2023 goto continue_loop;
2024 }
2025 block->dev_state = dev_state;
2026 block->dev_bytenr = dev_bytenr;
2027 block->logical_bytenr = bytenr;
2028 block->is_metadata = is_metadata;
2029 block->never_written = 0;
2030 block->iodone_w_error = 0;
2031 block->mirror_num = 0; /* unknown */
2032 block->flush_gen = dev_state->last_flush_gen + 1;
2033 block->submit_bio_bh_rw = submit_bio_bh_rw;
2034 if (NULL != bio) {
2035 block->is_iodone = 0;
2036 BUG_ON(NULL == bio_is_patched);
2037 if (!*bio_is_patched) {
2038 block->orig_bio_bh_private = bio->bi_private;
2039 block->orig_bio_bh_end_io.bio = bio->bi_end_io;
2040 block->next_in_same_bio = NULL;
2041 bio->bi_private = block;
2042 bio->bi_end_io = btrfsic_bio_end_io;
2043 *bio_is_patched = 1;
2044 } else {
2045 struct btrfsic_block *chained_block =
2046 (struct btrfsic_block *)
2047 bio->bi_private;
2048
2049 BUG_ON(NULL == chained_block);
2050 block->orig_bio_bh_private =
2051 chained_block->orig_bio_bh_private;
2052 block->orig_bio_bh_end_io.bio =
2053 chained_block->orig_bio_bh_end_io.bio;
2054 block->next_in_same_bio = chained_block;
2055 bio->bi_private = block;
2056 }
2057 } else if (NULL != bh) {
2058 block->is_iodone = 0;
2059 block->orig_bio_bh_private = bh->b_private;
2060 block->orig_bio_bh_end_io.bh = bh->b_end_io;
2061 block->next_in_same_bio = NULL;
2062 bh->b_private = block;
2063 bh->b_end_io = btrfsic_bh_end_io;
2064 } else {
2065 block->is_iodone = 1;
2066 block->orig_bio_bh_private = NULL;
2067 block->orig_bio_bh_end_io.bio = NULL;
2068 block->next_in_same_bio = NULL;
2069 }
2070 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2071 pr_info("New written %c-block @%llu (%s/%llu/%d)\n",
2072 is_metadata ? 'M' : 'D',
2073 block->logical_bytenr, block->dev_state->name,
2074 block->dev_bytenr, block->mirror_num);
2075 list_add(&block->all_blocks_node, &state->all_blocks_list);
2076 btrfsic_block_hashtable_add(block, &state->block_hashtable);
2077
2078 if (is_metadata) {
2079 ret = btrfsic_process_metablock(state, block,
2080 &block_ctx, 0, 0);
2081 if (ret)
2082 pr_info("btrfsic: process_metablock(root @%llu) failed!\n",
2083 dev_bytenr);
2084 }
2085 btrfsic_release_block_ctx(&block_ctx);
2086 }
2087
2088continue_loop:
2089 BUG_ON(!processed_len);
2090 dev_bytenr += processed_len;
2091 mapped_datav += processed_len >> PAGE_SHIFT;
2092 num_pages -= processed_len >> PAGE_SHIFT;
2093 goto again;
2094}
2095
2096static void btrfsic_bio_end_io(struct bio *bp)
2097{
2098 struct btrfsic_block *block = (struct btrfsic_block *)bp->bi_private;
2099 int iodone_w_error;
2100
2101 /* mutex is not held! This is not save if IO is not yet completed
2102 * on umount */
2103 iodone_w_error = 0;
2104 if (bp->bi_status)
2105 iodone_w_error = 1;
2106
2107 BUG_ON(NULL == block);
2108 bp->bi_private = block->orig_bio_bh_private;
2109 bp->bi_end_io = block->orig_bio_bh_end_io.bio;
2110
2111 do {
2112 struct btrfsic_block *next_block;
2113 struct btrfsic_dev_state *const dev_state = block->dev_state;
2114
2115 if ((dev_state->state->print_mask &
2116 BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
2117 pr_info("bio_end_io(err=%d) for %c @%llu (%s/%llu/%d)\n",
2118 bp->bi_status,
2119 btrfsic_get_block_type(dev_state->state, block),
2120 block->logical_bytenr, dev_state->name,
2121 block->dev_bytenr, block->mirror_num);
2122 next_block = block->next_in_same_bio;
2123 block->iodone_w_error = iodone_w_error;
2124 if (block->submit_bio_bh_rw & REQ_PREFLUSH) {
2125 dev_state->last_flush_gen++;
2126 if ((dev_state->state->print_mask &
2127 BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
2128 pr_info("bio_end_io() new %s flush_gen=%llu\n",
2129 dev_state->name,
2130 dev_state->last_flush_gen);
2131 }
2132 if (block->submit_bio_bh_rw & REQ_FUA)
2133 block->flush_gen = 0; /* FUA completed means block is
2134 * on disk */
2135 block->is_iodone = 1; /* for FLUSH, this releases the block */
2136 block = next_block;
2137 } while (NULL != block);
2138
2139 bp->bi_end_io(bp);
2140}
2141
2142static void btrfsic_bh_end_io(struct buffer_head *bh, int uptodate)
2143{
2144 struct btrfsic_block *block = (struct btrfsic_block *)bh->b_private;
2145 int iodone_w_error = !uptodate;
2146 struct btrfsic_dev_state *dev_state;
2147
2148 BUG_ON(NULL == block);
2149 dev_state = block->dev_state;
2150 if ((dev_state->state->print_mask & BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
2151 pr_info("bh_end_io(error=%d) for %c @%llu (%s/%llu/%d)\n",
2152 iodone_w_error,
2153 btrfsic_get_block_type(dev_state->state, block),
2154 block->logical_bytenr, block->dev_state->name,
2155 block->dev_bytenr, block->mirror_num);
2156
2157 block->iodone_w_error = iodone_w_error;
2158 if (block->submit_bio_bh_rw & REQ_PREFLUSH) {
2159 dev_state->last_flush_gen++;
2160 if ((dev_state->state->print_mask &
2161 BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
2162 pr_info("bh_end_io() new %s flush_gen=%llu\n",
2163 dev_state->name, dev_state->last_flush_gen);
2164 }
2165 if (block->submit_bio_bh_rw & REQ_FUA)
2166 block->flush_gen = 0; /* FUA completed means block is on disk */
2167
2168 bh->b_private = block->orig_bio_bh_private;
2169 bh->b_end_io = block->orig_bio_bh_end_io.bh;
2170 block->is_iodone = 1; /* for FLUSH, this releases the block */
2171 bh->b_end_io(bh, uptodate);
2172}
2173
2174static int btrfsic_process_written_superblock(
2175 struct btrfsic_state *state,
2176 struct btrfsic_block *const superblock,
2177 struct btrfs_super_block *const super_hdr)
2178{
2179 struct btrfs_fs_info *fs_info = state->fs_info;
2180 int pass;
2181
2182 superblock->generation = btrfs_super_generation(super_hdr);
2183 if (!(superblock->generation > state->max_superblock_generation ||
2184 0 == state->max_superblock_generation)) {
2185 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
2186 pr_info("btrfsic: superblock @%llu (%s/%llu/%d) with old gen %llu <= %llu\n",
2187 superblock->logical_bytenr,
2188 superblock->dev_state->name,
2189 superblock->dev_bytenr, superblock->mirror_num,
2190 btrfs_super_generation(super_hdr),
2191 state->max_superblock_generation);
2192 } else {
2193 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
2194 pr_info("btrfsic: got new superblock @%llu (%s/%llu/%d) with new gen %llu > %llu\n",
2195 superblock->logical_bytenr,
2196 superblock->dev_state->name,
2197 superblock->dev_bytenr, superblock->mirror_num,
2198 btrfs_super_generation(super_hdr),
2199 state->max_superblock_generation);
2200
2201 state->max_superblock_generation =
2202 btrfs_super_generation(super_hdr);
2203 state->latest_superblock = superblock;
2204 }
2205
2206 for (pass = 0; pass < 3; pass++) {
2207 int ret;
2208 u64 next_bytenr;
2209 struct btrfsic_block *next_block;
2210 struct btrfsic_block_data_ctx tmp_next_block_ctx;
2211 struct btrfsic_block_link *l;
2212 int num_copies;
2213 int mirror_num;
2214 const char *additional_string = NULL;
2215 struct btrfs_disk_key tmp_disk_key = {0};
2216
2217 btrfs_set_disk_key_objectid(&tmp_disk_key,
2218 BTRFS_ROOT_ITEM_KEY);
2219 btrfs_set_disk_key_objectid(&tmp_disk_key, 0);
2220
2221 switch (pass) {
2222 case 0:
2223 btrfs_set_disk_key_objectid(&tmp_disk_key,
2224 BTRFS_ROOT_TREE_OBJECTID);
2225 additional_string = "root ";
2226 next_bytenr = btrfs_super_root(super_hdr);
2227 if (state->print_mask &
2228 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
2229 pr_info("root@%llu\n", next_bytenr);
2230 break;
2231 case 1:
2232 btrfs_set_disk_key_objectid(&tmp_disk_key,
2233 BTRFS_CHUNK_TREE_OBJECTID);
2234 additional_string = "chunk ";
2235 next_bytenr = btrfs_super_chunk_root(super_hdr);
2236 if (state->print_mask &
2237 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
2238 pr_info("chunk@%llu\n", next_bytenr);
2239 break;
2240 case 2:
2241 btrfs_set_disk_key_objectid(&tmp_disk_key,
2242 BTRFS_TREE_LOG_OBJECTID);
2243 additional_string = "log ";
2244 next_bytenr = btrfs_super_log_root(super_hdr);
2245 if (0 == next_bytenr)
2246 continue;
2247 if (state->print_mask &
2248 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
2249 pr_info("log@%llu\n", next_bytenr);
2250 break;
2251 }
2252
2253 num_copies = btrfs_num_copies(fs_info, next_bytenr,
2254 BTRFS_SUPER_INFO_SIZE);
2255 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
2256 pr_info("num_copies(log_bytenr=%llu) = %d\n",
2257 next_bytenr, num_copies);
2258 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
2259 int was_created;
2260
2261 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2262 pr_info("btrfsic_process_written_superblock(mirror_num=%d)\n", mirror_num);
2263 ret = btrfsic_map_block(state, next_bytenr,
2264 BTRFS_SUPER_INFO_SIZE,
2265 &tmp_next_block_ctx,
2266 mirror_num);
2267 if (ret) {
2268 pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n",
2269 next_bytenr, mirror_num);
2270 return -1;
2271 }
2272
2273 next_block = btrfsic_block_lookup_or_add(
2274 state,
2275 &tmp_next_block_ctx,
2276 additional_string,
2277 1, 0, 1,
2278 mirror_num,
2279 &was_created);
2280 if (NULL == next_block) {
2281 pr_info("btrfsic: error, kmalloc failed!\n");
2282 btrfsic_release_block_ctx(&tmp_next_block_ctx);
2283 return -1;
2284 }
2285
2286 next_block->disk_key = tmp_disk_key;
2287 if (was_created)
2288 next_block->generation =
2289 BTRFSIC_GENERATION_UNKNOWN;
2290 l = btrfsic_block_link_lookup_or_add(
2291 state,
2292 &tmp_next_block_ctx,
2293 next_block,
2294 superblock,
2295 BTRFSIC_GENERATION_UNKNOWN);
2296 btrfsic_release_block_ctx(&tmp_next_block_ctx);
2297 if (NULL == l)
2298 return -1;
2299 }
2300 }
2301
2302 if (WARN_ON(-1 == btrfsic_check_all_ref_blocks(state, superblock, 0)))
2303 btrfsic_dump_tree(state);
2304
2305 return 0;
2306}
2307
2308static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state,
2309 struct btrfsic_block *const block,
2310 int recursion_level)
2311{
2312 const struct btrfsic_block_link *l;
2313 int ret = 0;
2314
2315 if (recursion_level >= 3 + BTRFS_MAX_LEVEL) {
2316 /*
2317 * Note that this situation can happen and does not
2318 * indicate an error in regular cases. It happens
2319 * when disk blocks are freed and later reused.
2320 * The check-integrity module is not aware of any
2321 * block free operations, it just recognizes block
2322 * write operations. Therefore it keeps the linkage
2323 * information for a block until a block is
2324 * rewritten. This can temporarily cause incorrect
2325 * and even circular linkage informations. This
2326 * causes no harm unless such blocks are referenced
2327 * by the most recent super block.
2328 */
2329 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2330 pr_info("btrfsic: abort cyclic linkage (case 1).\n");
2331
2332 return ret;
2333 }
2334
2335 /*
2336 * This algorithm is recursive because the amount of used stack
2337 * space is very small and the max recursion depth is limited.
2338 */
2339 list_for_each_entry(l, &block->ref_to_list, node_ref_to) {
2340 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2341 pr_info("rl=%d, %c @%llu (%s/%llu/%d) %u* refers to %c @%llu (%s/%llu/%d)\n",
2342 recursion_level,
2343 btrfsic_get_block_type(state, block),
2344 block->logical_bytenr, block->dev_state->name,
2345 block->dev_bytenr, block->mirror_num,
2346 l->ref_cnt,
2347 btrfsic_get_block_type(state, l->block_ref_to),
2348 l->block_ref_to->logical_bytenr,
2349 l->block_ref_to->dev_state->name,
2350 l->block_ref_to->dev_bytenr,
2351 l->block_ref_to->mirror_num);
2352 if (l->block_ref_to->never_written) {
2353 pr_info("btrfs: attempt to write superblock which references block %c @%llu (%s/%llu/%d) which is never written!\n",
2354 btrfsic_get_block_type(state, l->block_ref_to),
2355 l->block_ref_to->logical_bytenr,
2356 l->block_ref_to->dev_state->name,
2357 l->block_ref_to->dev_bytenr,
2358 l->block_ref_to->mirror_num);
2359 ret = -1;
2360 } else if (!l->block_ref_to->is_iodone) {
2361 pr_info("btrfs: attempt to write superblock which references block %c @%llu (%s/%llu/%d) which is not yet iodone!\n",
2362 btrfsic_get_block_type(state, l->block_ref_to),
2363 l->block_ref_to->logical_bytenr,
2364 l->block_ref_to->dev_state->name,
2365 l->block_ref_to->dev_bytenr,
2366 l->block_ref_to->mirror_num);
2367 ret = -1;
2368 } else if (l->block_ref_to->iodone_w_error) {
2369 pr_info("btrfs: attempt to write superblock which references block %c @%llu (%s/%llu/%d) which has write error!\n",
2370 btrfsic_get_block_type(state, l->block_ref_to),
2371 l->block_ref_to->logical_bytenr,
2372 l->block_ref_to->dev_state->name,
2373 l->block_ref_to->dev_bytenr,
2374 l->block_ref_to->mirror_num);
2375 ret = -1;
2376 } else if (l->parent_generation !=
2377 l->block_ref_to->generation &&
2378 BTRFSIC_GENERATION_UNKNOWN !=
2379 l->parent_generation &&
2380 BTRFSIC_GENERATION_UNKNOWN !=
2381 l->block_ref_to->generation) {
2382 pr_info("btrfs: attempt to write superblock which references block %c @%llu (%s/%llu/%d) with generation %llu != parent generation %llu!\n",
2383 btrfsic_get_block_type(state, l->block_ref_to),
2384 l->block_ref_to->logical_bytenr,
2385 l->block_ref_to->dev_state->name,
2386 l->block_ref_to->dev_bytenr,
2387 l->block_ref_to->mirror_num,
2388 l->block_ref_to->generation,
2389 l->parent_generation);
2390 ret = -1;
2391 } else if (l->block_ref_to->flush_gen >
2392 l->block_ref_to->dev_state->last_flush_gen) {
2393 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",
2394 btrfsic_get_block_type(state, l->block_ref_to),
2395 l->block_ref_to->logical_bytenr,
2396 l->block_ref_to->dev_state->name,
2397 l->block_ref_to->dev_bytenr,
2398 l->block_ref_to->mirror_num, block->flush_gen,
2399 l->block_ref_to->dev_state->last_flush_gen);
2400 ret = -1;
2401 } else if (-1 == btrfsic_check_all_ref_blocks(state,
2402 l->block_ref_to,
2403 recursion_level +
2404 1)) {
2405 ret = -1;
2406 }
2407 }
2408
2409 return ret;
2410}
2411
2412static int btrfsic_is_block_ref_by_superblock(
2413 const struct btrfsic_state *state,
2414 const struct btrfsic_block *block,
2415 int recursion_level)
2416{
2417 const struct btrfsic_block_link *l;
2418
2419 if (recursion_level >= 3 + BTRFS_MAX_LEVEL) {
2420 /* refer to comment at "abort cyclic linkage (case 1)" */
2421 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2422 pr_info("btrfsic: abort cyclic linkage (case 2).\n");
2423
2424 return 0;
2425 }
2426
2427 /*
2428 * This algorithm is recursive because the amount of used stack space
2429 * is very small and the max recursion depth is limited.
2430 */
2431 list_for_each_entry(l, &block->ref_from_list, node_ref_from) {
2432 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2433 pr_info("rl=%d, %c @%llu (%s/%llu/%d) is ref %u* from %c @%llu (%s/%llu/%d)\n",
2434 recursion_level,
2435 btrfsic_get_block_type(state, block),
2436 block->logical_bytenr, block->dev_state->name,
2437 block->dev_bytenr, block->mirror_num,
2438 l->ref_cnt,
2439 btrfsic_get_block_type(state, l->block_ref_from),
2440 l->block_ref_from->logical_bytenr,
2441 l->block_ref_from->dev_state->name,
2442 l->block_ref_from->dev_bytenr,
2443 l->block_ref_from->mirror_num);
2444 if (l->block_ref_from->is_superblock &&
2445 state->latest_superblock->dev_bytenr ==
2446 l->block_ref_from->dev_bytenr &&
2447 state->latest_superblock->dev_state->bdev ==
2448 l->block_ref_from->dev_state->bdev)
2449 return 1;
2450 else if (btrfsic_is_block_ref_by_superblock(state,
2451 l->block_ref_from,
2452 recursion_level +
2453 1))
2454 return 1;
2455 }
2456
2457 return 0;
2458}
2459
2460static void btrfsic_print_add_link(const struct btrfsic_state *state,
2461 const struct btrfsic_block_link *l)
2462{
2463 pr_info("Add %u* link from %c @%llu (%s/%llu/%d) to %c @%llu (%s/%llu/%d).\n",
2464 l->ref_cnt,
2465 btrfsic_get_block_type(state, l->block_ref_from),
2466 l->block_ref_from->logical_bytenr,
2467 l->block_ref_from->dev_state->name,
2468 l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num,
2469 btrfsic_get_block_type(state, l->block_ref_to),
2470 l->block_ref_to->logical_bytenr,
2471 l->block_ref_to->dev_state->name, l->block_ref_to->dev_bytenr,
2472 l->block_ref_to->mirror_num);
2473}
2474
2475static void btrfsic_print_rem_link(const struct btrfsic_state *state,
2476 const struct btrfsic_block_link *l)
2477{
2478 pr_info("Rem %u* link from %c @%llu (%s/%llu/%d) to %c @%llu (%s/%llu/%d).\n",
2479 l->ref_cnt,
2480 btrfsic_get_block_type(state, l->block_ref_from),
2481 l->block_ref_from->logical_bytenr,
2482 l->block_ref_from->dev_state->name,
2483 l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num,
2484 btrfsic_get_block_type(state, l->block_ref_to),
2485 l->block_ref_to->logical_bytenr,
2486 l->block_ref_to->dev_state->name, l->block_ref_to->dev_bytenr,
2487 l->block_ref_to->mirror_num);
2488}
2489
2490static char btrfsic_get_block_type(const struct btrfsic_state *state,
2491 const struct btrfsic_block *block)
2492{
2493 if (block->is_superblock &&
2494 state->latest_superblock->dev_bytenr == block->dev_bytenr &&
2495 state->latest_superblock->dev_state->bdev == block->dev_state->bdev)
2496 return 'S';
2497 else if (block->is_superblock)
2498 return 's';
2499 else if (block->is_metadata)
2500 return 'M';
2501 else
2502 return 'D';
2503}
2504
2505static void btrfsic_dump_tree(const struct btrfsic_state *state)
2506{
2507 btrfsic_dump_tree_sub(state, state->latest_superblock, 0);
2508}
2509
2510static void btrfsic_dump_tree_sub(const struct btrfsic_state *state,
2511 const struct btrfsic_block *block,
2512 int indent_level)
2513{
2514 const struct btrfsic_block_link *l;
2515 int indent_add;
2516 static char buf[80];
2517 int cursor_position;
2518
2519 /*
2520 * Should better fill an on-stack buffer with a complete line and
2521 * dump it at once when it is time to print a newline character.
2522 */
2523
2524 /*
2525 * This algorithm is recursive because the amount of used stack space
2526 * is very small and the max recursion depth is limited.
2527 */
2528 indent_add = sprintf(buf, "%c-%llu(%s/%llu/%u)",
2529 btrfsic_get_block_type(state, block),
2530 block->logical_bytenr, block->dev_state->name,
2531 block->dev_bytenr, block->mirror_num);
2532 if (indent_level + indent_add > BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) {
2533 printk("[...]\n");
2534 return;
2535 }
2536 printk(buf);
2537 indent_level += indent_add;
2538 if (list_empty(&block->ref_to_list)) {
2539 printk("\n");
2540 return;
2541 }
2542 if (block->mirror_num > 1 &&
2543 !(state->print_mask & BTRFSIC_PRINT_MASK_TREE_WITH_ALL_MIRRORS)) {
2544 printk(" [...]\n");
2545 return;
2546 }
2547
2548 cursor_position = indent_level;
2549 list_for_each_entry(l, &block->ref_to_list, node_ref_to) {
2550 while (cursor_position < indent_level) {
2551 printk(" ");
2552 cursor_position++;
2553 }
2554 if (l->ref_cnt > 1)
2555 indent_add = sprintf(buf, " %d*--> ", l->ref_cnt);
2556 else
2557 indent_add = sprintf(buf, " --> ");
2558 if (indent_level + indent_add >
2559 BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) {
2560 printk("[...]\n");
2561 cursor_position = 0;
2562 continue;
2563 }
2564
2565 printk(buf);
2566
2567 btrfsic_dump_tree_sub(state, l->block_ref_to,
2568 indent_level + indent_add);
2569 cursor_position = 0;
2570 }
2571}
2572
2573static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add(
2574 struct btrfsic_state *state,
2575 struct btrfsic_block_data_ctx *next_block_ctx,
2576 struct btrfsic_block *next_block,
2577 struct btrfsic_block *from_block,
2578 u64 parent_generation)
2579{
2580 struct btrfsic_block_link *l;
2581
2582 l = btrfsic_block_link_hashtable_lookup(next_block_ctx->dev->bdev,
2583 next_block_ctx->dev_bytenr,
2584 from_block->dev_state->bdev,
2585 from_block->dev_bytenr,
2586 &state->block_link_hashtable);
2587 if (NULL == l) {
2588 l = btrfsic_block_link_alloc();
2589 if (NULL == l) {
2590 pr_info("btrfsic: error, kmalloc failed!\n");
2591 return NULL;
2592 }
2593
2594 l->block_ref_to = next_block;
2595 l->block_ref_from = from_block;
2596 l->ref_cnt = 1;
2597 l->parent_generation = parent_generation;
2598
2599 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2600 btrfsic_print_add_link(state, l);
2601
2602 list_add(&l->node_ref_to, &from_block->ref_to_list);
2603 list_add(&l->node_ref_from, &next_block->ref_from_list);
2604
2605 btrfsic_block_link_hashtable_add(l,
2606 &state->block_link_hashtable);
2607 } else {
2608 l->ref_cnt++;
2609 l->parent_generation = parent_generation;
2610 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2611 btrfsic_print_add_link(state, l);
2612 }
2613
2614 return l;
2615}
2616
2617static struct btrfsic_block *btrfsic_block_lookup_or_add(
2618 struct btrfsic_state *state,
2619 struct btrfsic_block_data_ctx *block_ctx,
2620 const char *additional_string,
2621 int is_metadata,
2622 int is_iodone,
2623 int never_written,
2624 int mirror_num,
2625 int *was_created)
2626{
2627 struct btrfsic_block *block;
2628
2629 block = btrfsic_block_hashtable_lookup(block_ctx->dev->bdev,
2630 block_ctx->dev_bytenr,
2631 &state->block_hashtable);
2632 if (NULL == block) {
2633 struct btrfsic_dev_state *dev_state;
2634
2635 block = btrfsic_block_alloc();
2636 if (NULL == block) {
2637 pr_info("btrfsic: error, kmalloc failed!\n");
2638 return NULL;
2639 }
2640 dev_state = btrfsic_dev_state_lookup(block_ctx->dev->bdev->bd_dev);
2641 if (NULL == dev_state) {
2642 pr_info("btrfsic: error, lookup dev_state failed!\n");
2643 btrfsic_block_free(block);
2644 return NULL;
2645 }
2646 block->dev_state = dev_state;
2647 block->dev_bytenr = block_ctx->dev_bytenr;
2648 block->logical_bytenr = block_ctx->start;
2649 block->is_metadata = is_metadata;
2650 block->is_iodone = is_iodone;
2651 block->never_written = never_written;
2652 block->mirror_num = mirror_num;
2653 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2654 pr_info("New %s%c-block @%llu (%s/%llu/%d)\n",
2655 additional_string,
2656 btrfsic_get_block_type(state, block),
2657 block->logical_bytenr, dev_state->name,
2658 block->dev_bytenr, mirror_num);
2659 list_add(&block->all_blocks_node, &state->all_blocks_list);
2660 btrfsic_block_hashtable_add(block, &state->block_hashtable);
2661 if (NULL != was_created)
2662 *was_created = 1;
2663 } else {
2664 if (NULL != was_created)
2665 *was_created = 0;
2666 }
2667
2668 return block;
2669}
2670
2671static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state,
2672 u64 bytenr,
2673 struct btrfsic_dev_state *dev_state,
2674 u64 dev_bytenr)
2675{
2676 struct btrfs_fs_info *fs_info = state->fs_info;
2677 struct btrfsic_block_data_ctx block_ctx;
2678 int num_copies;
2679 int mirror_num;
2680 int match = 0;
2681 int ret;
2682
2683 num_copies = btrfs_num_copies(fs_info, bytenr, state->metablock_size);
2684
2685 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
2686 ret = btrfsic_map_block(state, bytenr, state->metablock_size,
2687 &block_ctx, mirror_num);
2688 if (ret) {
2689 pr_info("btrfsic: btrfsic_map_block(logical @%llu, mirror %d) failed!\n",
2690 bytenr, mirror_num);
2691 continue;
2692 }
2693
2694 if (dev_state->bdev == block_ctx.dev->bdev &&
2695 dev_bytenr == block_ctx.dev_bytenr) {
2696 match++;
2697 btrfsic_release_block_ctx(&block_ctx);
2698 break;
2699 }
2700 btrfsic_release_block_ctx(&block_ctx);
2701 }
2702
2703 if (WARN_ON(!match)) {
2704 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",
2705 bytenr, dev_state->name, dev_bytenr);
2706 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
2707 ret = btrfsic_map_block(state, bytenr,
2708 state->metablock_size,
2709 &block_ctx, mirror_num);
2710 if (ret)
2711 continue;
2712
2713 pr_info("Read logical bytenr @%llu maps to (%s/%llu/%d)\n",
2714 bytenr, block_ctx.dev->name,
2715 block_ctx.dev_bytenr, mirror_num);
2716 }
2717 }
2718}
2719
2720static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev)
2721{
2722 return btrfsic_dev_state_hashtable_lookup(dev,
2723 &btrfsic_dev_state_hashtable);
2724}
2725
2726int btrfsic_submit_bh(int op, int op_flags, struct buffer_head *bh)
2727{
2728 struct btrfsic_dev_state *dev_state;
2729
2730 if (!btrfsic_is_initialized)
2731 return submit_bh(op, op_flags, bh);
2732
2733 mutex_lock(&btrfsic_mutex);
2734 /* since btrfsic_submit_bh() might also be called before
2735 * btrfsic_mount(), this might return NULL */
2736 dev_state = btrfsic_dev_state_lookup(bh->b_bdev->bd_dev);
2737
2738 /* Only called to write the superblock (incl. FLUSH/FUA) */
2739 if (NULL != dev_state &&
2740 (op == REQ_OP_WRITE) && bh->b_size > 0) {
2741 u64 dev_bytenr;
2742
2743 dev_bytenr = BTRFS_BDEV_BLOCKSIZE * bh->b_blocknr;
2744 if (dev_state->state->print_mask &
2745 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
2746 pr_info("submit_bh(op=0x%x,0x%x, blocknr=%llu (bytenr %llu), size=%zu, data=%p, bdev=%p)\n",
2747 op, op_flags, (unsigned long long)bh->b_blocknr,
2748 dev_bytenr, bh->b_size, bh->b_data, bh->b_bdev);
2749 btrfsic_process_written_block(dev_state, dev_bytenr,
2750 &bh->b_data, 1, NULL,
2751 NULL, bh, op_flags);
2752 } else if (NULL != dev_state && (op_flags & REQ_PREFLUSH)) {
2753 if (dev_state->state->print_mask &
2754 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
2755 pr_info("submit_bh(op=0x%x,0x%x FLUSH, bdev=%p)\n",
2756 op, op_flags, bh->b_bdev);
2757 if (!dev_state->dummy_block_for_bio_bh_flush.is_iodone) {
2758 if ((dev_state->state->print_mask &
2759 (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH |
2760 BTRFSIC_PRINT_MASK_VERBOSE)))
2761 pr_info("btrfsic_submit_bh(%s) with FLUSH but dummy block already in use (ignored)!\n",
2762 dev_state->name);
2763 } else {
2764 struct btrfsic_block *const block =
2765 &dev_state->dummy_block_for_bio_bh_flush;
2766
2767 block->is_iodone = 0;
2768 block->never_written = 0;
2769 block->iodone_w_error = 0;
2770 block->flush_gen = dev_state->last_flush_gen + 1;
2771 block->submit_bio_bh_rw = op_flags;
2772 block->orig_bio_bh_private = bh->b_private;
2773 block->orig_bio_bh_end_io.bh = bh->b_end_io;
2774 block->next_in_same_bio = NULL;
2775 bh->b_private = block;
2776 bh->b_end_io = btrfsic_bh_end_io;
2777 }
2778 }
2779 mutex_unlock(&btrfsic_mutex);
2780 return submit_bh(op, op_flags, bh);
2781}
2782
2783static void __btrfsic_submit_bio(struct bio *bio)
2784{
2785 struct btrfsic_dev_state *dev_state;
2786
2787 if (!btrfsic_is_initialized)
2788 return;
2789
2790 mutex_lock(&btrfsic_mutex);
2791 /* since btrfsic_submit_bio() is also called before
2792 * btrfsic_mount(), this might return NULL */
2793 dev_state = btrfsic_dev_state_lookup(bio_dev(bio) + bio->bi_partno);
2794 if (NULL != dev_state &&
2795 (bio_op(bio) == REQ_OP_WRITE) && bio_has_data(bio)) {
2796 unsigned int i = 0;
2797 u64 dev_bytenr;
2798 u64 cur_bytenr;
2799 struct bio_vec bvec;
2800 struct bvec_iter iter;
2801 int bio_is_patched;
2802 char **mapped_datav;
2803 unsigned int segs = bio_segments(bio);
2804
2805 dev_bytenr = 512 * bio->bi_iter.bi_sector;
2806 bio_is_patched = 0;
2807 if (dev_state->state->print_mask &
2808 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
2809 pr_info("submit_bio(rw=%d,0x%x, bi_vcnt=%u, bi_sector=%llu (bytenr %llu), bi_disk=%p)\n",
2810 bio_op(bio), bio->bi_opf, segs,
2811 (unsigned long long)bio->bi_iter.bi_sector,
2812 dev_bytenr, bio->bi_disk);
2813
2814 mapped_datav = kmalloc_array(segs,
2815 sizeof(*mapped_datav), GFP_NOFS);
2816 if (!mapped_datav)
2817 goto leave;
2818 cur_bytenr = dev_bytenr;
2819
2820 bio_for_each_segment(bvec, bio, iter) {
2821 BUG_ON(bvec.bv_len != PAGE_SIZE);
2822 mapped_datav[i] = kmap(bvec.bv_page);
2823 i++;
2824
2825 if (dev_state->state->print_mask &
2826 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE)
2827 pr_info("#%u: bytenr=%llu, len=%u, offset=%u\n",
2828 i, cur_bytenr, bvec.bv_len, bvec.bv_offset);
2829 cur_bytenr += bvec.bv_len;
2830 }
2831 btrfsic_process_written_block(dev_state, dev_bytenr,
2832 mapped_datav, segs,
2833 bio, &bio_is_patched,
2834 NULL, bio->bi_opf);
2835 bio_for_each_segment(bvec, bio, iter)
2836 kunmap(bvec.bv_page);
2837 kfree(mapped_datav);
2838 } else if (NULL != dev_state && (bio->bi_opf & REQ_PREFLUSH)) {
2839 if (dev_state->state->print_mask &
2840 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
2841 pr_info("submit_bio(rw=%d,0x%x FLUSH, disk=%p)\n",
2842 bio_op(bio), bio->bi_opf, bio->bi_disk);
2843 if (!dev_state->dummy_block_for_bio_bh_flush.is_iodone) {
2844 if ((dev_state->state->print_mask &
2845 (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH |
2846 BTRFSIC_PRINT_MASK_VERBOSE)))
2847 pr_info("btrfsic_submit_bio(%s) with FLUSH but dummy block already in use (ignored)!\n",
2848 dev_state->name);
2849 } else {
2850 struct btrfsic_block *const block =
2851 &dev_state->dummy_block_for_bio_bh_flush;
2852
2853 block->is_iodone = 0;
2854 block->never_written = 0;
2855 block->iodone_w_error = 0;
2856 block->flush_gen = dev_state->last_flush_gen + 1;
2857 block->submit_bio_bh_rw = bio->bi_opf;
2858 block->orig_bio_bh_private = bio->bi_private;
2859 block->orig_bio_bh_end_io.bio = bio->bi_end_io;
2860 block->next_in_same_bio = NULL;
2861 bio->bi_private = block;
2862 bio->bi_end_io = btrfsic_bio_end_io;
2863 }
2864 }
2865leave:
2866 mutex_unlock(&btrfsic_mutex);
2867}
2868
2869void btrfsic_submit_bio(struct bio *bio)
2870{
2871 __btrfsic_submit_bio(bio);
2872 submit_bio(bio);
2873}
2874
2875int btrfsic_submit_bio_wait(struct bio *bio)
2876{
2877 __btrfsic_submit_bio(bio);
2878 return submit_bio_wait(bio);
2879}
2880
2881int btrfsic_mount(struct btrfs_fs_info *fs_info,
2882 struct btrfs_fs_devices *fs_devices,
2883 int including_extent_data, u32 print_mask)
2884{
2885 int ret;
2886 struct btrfsic_state *state;
2887 struct list_head *dev_head = &fs_devices->devices;
2888 struct btrfs_device *device;
2889
2890 if (fs_info->nodesize & ((u64)PAGE_SIZE - 1)) {
2891 pr_info("btrfsic: cannot handle nodesize %d not being a multiple of PAGE_SIZE %ld!\n",
2892 fs_info->nodesize, PAGE_SIZE);
2893 return -1;
2894 }
2895 if (fs_info->sectorsize & ((u64)PAGE_SIZE - 1)) {
2896 pr_info("btrfsic: cannot handle sectorsize %d not being a multiple of PAGE_SIZE %ld!\n",
2897 fs_info->sectorsize, PAGE_SIZE);
2898 return -1;
2899 }
2900 state = kvzalloc(sizeof(*state), GFP_KERNEL);
2901 if (!state) {
2902 pr_info("btrfs check-integrity: allocation failed!\n");
2903 return -ENOMEM;
2904 }
2905
2906 if (!btrfsic_is_initialized) {
2907 mutex_init(&btrfsic_mutex);
2908 btrfsic_dev_state_hashtable_init(&btrfsic_dev_state_hashtable);
2909 btrfsic_is_initialized = 1;
2910 }
2911 mutex_lock(&btrfsic_mutex);
2912 state->fs_info = fs_info;
2913 state->print_mask = print_mask;
2914 state->include_extent_data = including_extent_data;
2915 state->csum_size = 0;
2916 state->metablock_size = fs_info->nodesize;
2917 state->datablock_size = fs_info->sectorsize;
2918 INIT_LIST_HEAD(&state->all_blocks_list);
2919 btrfsic_block_hashtable_init(&state->block_hashtable);
2920 btrfsic_block_link_hashtable_init(&state->block_link_hashtable);
2921 state->max_superblock_generation = 0;
2922 state->latest_superblock = NULL;
2923
2924 list_for_each_entry(device, dev_head, dev_list) {
2925 struct btrfsic_dev_state *ds;
2926 const char *p;
2927
2928 if (!device->bdev || !device->name)
2929 continue;
2930
2931 ds = btrfsic_dev_state_alloc();
2932 if (NULL == ds) {
2933 pr_info("btrfs check-integrity: kmalloc() failed!\n");
2934 mutex_unlock(&btrfsic_mutex);
2935 return -ENOMEM;
2936 }
2937 ds->bdev = device->bdev;
2938 ds->state = state;
2939 bdevname(ds->bdev, ds->name);
2940 ds->name[BDEVNAME_SIZE - 1] = '\0';
2941 p = kbasename(ds->name);
2942 strlcpy(ds->name, p, sizeof(ds->name));
2943 btrfsic_dev_state_hashtable_add(ds,
2944 &btrfsic_dev_state_hashtable);
2945 }
2946
2947 ret = btrfsic_process_superblock(state, fs_devices);
2948 if (0 != ret) {
2949 mutex_unlock(&btrfsic_mutex);
2950 btrfsic_unmount(fs_devices);
2951 return ret;
2952 }
2953
2954 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_DATABASE)
2955 btrfsic_dump_database(state);
2956 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_TREE)
2957 btrfsic_dump_tree(state);
2958
2959 mutex_unlock(&btrfsic_mutex);
2960 return 0;
2961}
2962
2963void btrfsic_unmount(struct btrfs_fs_devices *fs_devices)
2964{
2965 struct btrfsic_block *b_all, *tmp_all;
2966 struct btrfsic_state *state;
2967 struct list_head *dev_head = &fs_devices->devices;
2968 struct btrfs_device *device;
2969
2970 if (!btrfsic_is_initialized)
2971 return;
2972
2973 mutex_lock(&btrfsic_mutex);
2974
2975 state = NULL;
2976 list_for_each_entry(device, dev_head, dev_list) {
2977 struct btrfsic_dev_state *ds;
2978
2979 if (!device->bdev || !device->name)
2980 continue;
2981
2982 ds = btrfsic_dev_state_hashtable_lookup(
2983 device->bdev->bd_dev,
2984 &btrfsic_dev_state_hashtable);
2985 if (NULL != ds) {
2986 state = ds->state;
2987 btrfsic_dev_state_hashtable_remove(ds);
2988 btrfsic_dev_state_free(ds);
2989 }
2990 }
2991
2992 if (NULL == state) {
2993 pr_info("btrfsic: error, cannot find state information on umount!\n");
2994 mutex_unlock(&btrfsic_mutex);
2995 return;
2996 }
2997
2998 /*
2999 * Don't care about keeping the lists' state up to date,
3000 * just free all memory that was allocated dynamically.
3001 * Free the blocks and the block_links.
3002 */
3003 list_for_each_entry_safe(b_all, tmp_all, &state->all_blocks_list,
3004 all_blocks_node) {
3005 struct btrfsic_block_link *l, *tmp;
3006
3007 list_for_each_entry_safe(l, tmp, &b_all->ref_to_list,
3008 node_ref_to) {
3009 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
3010 btrfsic_print_rem_link(state, l);
3011
3012 l->ref_cnt--;
3013 if (0 == l->ref_cnt)
3014 btrfsic_block_link_free(l);
3015 }
3016
3017 if (b_all->is_iodone || b_all->never_written)
3018 btrfsic_block_free(b_all);
3019 else
3020 pr_info("btrfs: attempt to free %c-block @%llu (%s/%llu/%d) on umount which is not yet iodone!\n",
3021 btrfsic_get_block_type(state, b_all),
3022 b_all->logical_bytenr, b_all->dev_state->name,
3023 b_all->dev_bytenr, b_all->mirror_num);
3024 }
3025
3026 mutex_unlock(&btrfsic_mutex);
3027
3028 kvfree(state);
3029}
1/*
2 * Copyright (C) STRATO AG 2011. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19/*
20 * This module can be used to catch cases when the btrfs kernel
21 * code executes write requests to the disk that bring the file
22 * system in an inconsistent state. In such a state, a power-loss
23 * or kernel panic event would cause that the data on disk is
24 * lost or at least damaged.
25 *
26 * Code is added that examines all block write requests during
27 * runtime (including writes of the super block). Three rules
28 * are verified and an error is printed on violation of the
29 * rules:
30 * 1. It is not allowed to write a disk block which is
31 * currently referenced by the super block (either directly
32 * or indirectly).
33 * 2. When a super block is written, it is verified that all
34 * referenced (directly or indirectly) blocks fulfill the
35 * following requirements:
36 * 2a. All referenced blocks have either been present when
37 * the file system was mounted, (i.e., they have been
38 * referenced by the super block) or they have been
39 * written since then and the write completion callback
40 * was called and no write error was indicated and a
41 * FLUSH request to the device where these blocks are
42 * located was received and completed.
43 * 2b. All referenced blocks need to have a generation
44 * number which is equal to the parent's number.
45 *
46 * One issue that was found using this module was that the log
47 * tree on disk became temporarily corrupted because disk blocks
48 * that had been in use for the log tree had been freed and
49 * reused too early, while being referenced by the written super
50 * block.
51 *
52 * The search term in the kernel log that can be used to filter
53 * on the existence of detected integrity issues is
54 * "btrfs: attempt".
55 *
56 * The integrity check is enabled via mount options. These
57 * mount options are only supported if the integrity check
58 * tool is compiled by defining BTRFS_FS_CHECK_INTEGRITY.
59 *
60 * Example #1, apply integrity checks to all metadata:
61 * mount /dev/sdb1 /mnt -o check_int
62 *
63 * Example #2, apply integrity checks to all metadata and
64 * to data extents:
65 * mount /dev/sdb1 /mnt -o check_int_data
66 *
67 * Example #3, apply integrity checks to all metadata and dump
68 * the tree that the super block references to kernel messages
69 * each time after a super block was written:
70 * mount /dev/sdb1 /mnt -o check_int,check_int_print_mask=263
71 *
72 * If the integrity check tool is included and activated in
73 * the mount options, plenty of kernel memory is used, and
74 * plenty of additional CPU cycles are spent. Enabling this
75 * functionality is not intended for normal use. In most
76 * cases, unless you are a btrfs developer who needs to verify
77 * the integrity of (super)-block write requests, do not
78 * enable the config option BTRFS_FS_CHECK_INTEGRITY to
79 * include and compile the integrity check tool.
80 *
81 * Expect millions of lines of information in the kernel log with an
82 * enabled check_int_print_mask. Therefore set LOG_BUF_SHIFT in the
83 * kernel config to at least 26 (which is 64MB). Usually the value is
84 * limited to 21 (which is 2MB) in init/Kconfig. The file needs to be
85 * changed like this before LOG_BUF_SHIFT can be set to a high value:
86 * config LOG_BUF_SHIFT
87 * int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
88 * range 12 30
89 */
90
91#include <linux/sched.h>
92#include <linux/slab.h>
93#include <linux/buffer_head.h>
94#include <linux/mutex.h>
95#include <linux/genhd.h>
96#include <linux/blkdev.h>
97#include "ctree.h"
98#include "disk-io.h"
99#include "hash.h"
100#include "transaction.h"
101#include "extent_io.h"
102#include "volumes.h"
103#include "print-tree.h"
104#include "locking.h"
105#include "check-integrity.h"
106#include "rcu-string.h"
107
108#define BTRFSIC_BLOCK_HASHTABLE_SIZE 0x10000
109#define BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE 0x10000
110#define BTRFSIC_DEV2STATE_HASHTABLE_SIZE 0x100
111#define BTRFSIC_BLOCK_MAGIC_NUMBER 0x14491051
112#define BTRFSIC_BLOCK_LINK_MAGIC_NUMBER 0x11070807
113#define BTRFSIC_DEV2STATE_MAGIC_NUMBER 0x20111530
114#define BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER 20111300
115#define BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL (200 - 6) /* in characters,
116 * excluding " [...]" */
117#define BTRFSIC_GENERATION_UNKNOWN ((u64)-1)
118
119/*
120 * The definition of the bitmask fields for the print_mask.
121 * They are specified with the mount option check_integrity_print_mask.
122 */
123#define BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE 0x00000001
124#define BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION 0x00000002
125#define BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE 0x00000004
126#define BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE 0x00000008
127#define BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH 0x00000010
128#define BTRFSIC_PRINT_MASK_END_IO_BIO_BH 0x00000020
129#define BTRFSIC_PRINT_MASK_VERBOSE 0x00000040
130#define BTRFSIC_PRINT_MASK_VERY_VERBOSE 0x00000080
131#define BTRFSIC_PRINT_MASK_INITIAL_TREE 0x00000100
132#define BTRFSIC_PRINT_MASK_INITIAL_ALL_TREES 0x00000200
133#define BTRFSIC_PRINT_MASK_INITIAL_DATABASE 0x00000400
134#define BTRFSIC_PRINT_MASK_NUM_COPIES 0x00000800
135#define BTRFSIC_PRINT_MASK_TREE_WITH_ALL_MIRRORS 0x00001000
136#define BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE 0x00002000
137
138struct btrfsic_dev_state;
139struct btrfsic_state;
140
141struct btrfsic_block {
142 u32 magic_num; /* only used for debug purposes */
143 unsigned int is_metadata:1; /* if it is meta-data, not data-data */
144 unsigned int is_superblock:1; /* if it is one of the superblocks */
145 unsigned int is_iodone:1; /* if is done by lower subsystem */
146 unsigned int iodone_w_error:1; /* error was indicated to endio */
147 unsigned int never_written:1; /* block was added because it was
148 * referenced, not because it was
149 * written */
150 unsigned int mirror_num; /* large enough to hold
151 * BTRFS_SUPER_MIRROR_MAX */
152 struct btrfsic_dev_state *dev_state;
153 u64 dev_bytenr; /* key, physical byte num on disk */
154 u64 logical_bytenr; /* logical byte num on disk */
155 u64 generation;
156 struct btrfs_disk_key disk_key; /* extra info to print in case of
157 * issues, will not always be correct */
158 struct list_head collision_resolving_node; /* list node */
159 struct list_head all_blocks_node; /* list node */
160
161 /* the following two lists contain block_link items */
162 struct list_head ref_to_list; /* list */
163 struct list_head ref_from_list; /* list */
164 struct btrfsic_block *next_in_same_bio;
165 void *orig_bio_bh_private;
166 union {
167 bio_end_io_t *bio;
168 bh_end_io_t *bh;
169 } orig_bio_bh_end_io;
170 int submit_bio_bh_rw;
171 u64 flush_gen; /* only valid if !never_written */
172};
173
174/*
175 * Elements of this type are allocated dynamically and required because
176 * each block object can refer to and can be ref from multiple blocks.
177 * The key to lookup them in the hashtable is the dev_bytenr of
178 * the block ref to plus the one from the block refered from.
179 * The fact that they are searchable via a hashtable and that a
180 * ref_cnt is maintained is not required for the btrfs integrity
181 * check algorithm itself, it is only used to make the output more
182 * beautiful in case that an error is detected (an error is defined
183 * as a write operation to a block while that block is still referenced).
184 */
185struct btrfsic_block_link {
186 u32 magic_num; /* only used for debug purposes */
187 u32 ref_cnt;
188 struct list_head node_ref_to; /* list node */
189 struct list_head node_ref_from; /* list node */
190 struct list_head collision_resolving_node; /* list node */
191 struct btrfsic_block *block_ref_to;
192 struct btrfsic_block *block_ref_from;
193 u64 parent_generation;
194};
195
196struct btrfsic_dev_state {
197 u32 magic_num; /* only used for debug purposes */
198 struct block_device *bdev;
199 struct btrfsic_state *state;
200 struct list_head collision_resolving_node; /* list node */
201 struct btrfsic_block dummy_block_for_bio_bh_flush;
202 u64 last_flush_gen;
203 char name[BDEVNAME_SIZE];
204};
205
206struct btrfsic_block_hashtable {
207 struct list_head table[BTRFSIC_BLOCK_HASHTABLE_SIZE];
208};
209
210struct btrfsic_block_link_hashtable {
211 struct list_head table[BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE];
212};
213
214struct btrfsic_dev_state_hashtable {
215 struct list_head table[BTRFSIC_DEV2STATE_HASHTABLE_SIZE];
216};
217
218struct btrfsic_block_data_ctx {
219 u64 start; /* virtual bytenr */
220 u64 dev_bytenr; /* physical bytenr on device */
221 u32 len;
222 struct btrfsic_dev_state *dev;
223 char **datav;
224 struct page **pagev;
225 void *mem_to_free;
226};
227
228/* This structure is used to implement recursion without occupying
229 * any stack space, refer to btrfsic_process_metablock() */
230struct btrfsic_stack_frame {
231 u32 magic;
232 u32 nr;
233 int error;
234 int i;
235 int limit_nesting;
236 int num_copies;
237 int mirror_num;
238 struct btrfsic_block *block;
239 struct btrfsic_block_data_ctx *block_ctx;
240 struct btrfsic_block *next_block;
241 struct btrfsic_block_data_ctx next_block_ctx;
242 struct btrfs_header *hdr;
243 struct btrfsic_stack_frame *prev;
244};
245
246/* Some state per mounted filesystem */
247struct btrfsic_state {
248 u32 print_mask;
249 int include_extent_data;
250 int csum_size;
251 struct list_head all_blocks_list;
252 struct btrfsic_block_hashtable block_hashtable;
253 struct btrfsic_block_link_hashtable block_link_hashtable;
254 struct btrfs_root *root;
255 u64 max_superblock_generation;
256 struct btrfsic_block *latest_superblock;
257 u32 metablock_size;
258 u32 datablock_size;
259};
260
261static void btrfsic_block_init(struct btrfsic_block *b);
262static struct btrfsic_block *btrfsic_block_alloc(void);
263static void btrfsic_block_free(struct btrfsic_block *b);
264static void btrfsic_block_link_init(struct btrfsic_block_link *n);
265static struct btrfsic_block_link *btrfsic_block_link_alloc(void);
266static void btrfsic_block_link_free(struct btrfsic_block_link *n);
267static void btrfsic_dev_state_init(struct btrfsic_dev_state *ds);
268static struct btrfsic_dev_state *btrfsic_dev_state_alloc(void);
269static void btrfsic_dev_state_free(struct btrfsic_dev_state *ds);
270static void btrfsic_block_hashtable_init(struct btrfsic_block_hashtable *h);
271static void btrfsic_block_hashtable_add(struct btrfsic_block *b,
272 struct btrfsic_block_hashtable *h);
273static void btrfsic_block_hashtable_remove(struct btrfsic_block *b);
274static struct btrfsic_block *btrfsic_block_hashtable_lookup(
275 struct block_device *bdev,
276 u64 dev_bytenr,
277 struct btrfsic_block_hashtable *h);
278static void btrfsic_block_link_hashtable_init(
279 struct btrfsic_block_link_hashtable *h);
280static void btrfsic_block_link_hashtable_add(
281 struct btrfsic_block_link *l,
282 struct btrfsic_block_link_hashtable *h);
283static void btrfsic_block_link_hashtable_remove(struct btrfsic_block_link *l);
284static struct btrfsic_block_link *btrfsic_block_link_hashtable_lookup(
285 struct block_device *bdev_ref_to,
286 u64 dev_bytenr_ref_to,
287 struct block_device *bdev_ref_from,
288 u64 dev_bytenr_ref_from,
289 struct btrfsic_block_link_hashtable *h);
290static void btrfsic_dev_state_hashtable_init(
291 struct btrfsic_dev_state_hashtable *h);
292static void btrfsic_dev_state_hashtable_add(
293 struct btrfsic_dev_state *ds,
294 struct btrfsic_dev_state_hashtable *h);
295static void btrfsic_dev_state_hashtable_remove(struct btrfsic_dev_state *ds);
296static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(
297 struct block_device *bdev,
298 struct btrfsic_dev_state_hashtable *h);
299static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void);
300static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf);
301static int btrfsic_process_superblock(struct btrfsic_state *state,
302 struct btrfs_fs_devices *fs_devices);
303static int btrfsic_process_metablock(struct btrfsic_state *state,
304 struct btrfsic_block *block,
305 struct btrfsic_block_data_ctx *block_ctx,
306 int limit_nesting, int force_iodone_flag);
307static void btrfsic_read_from_block_data(
308 struct btrfsic_block_data_ctx *block_ctx,
309 void *dst, u32 offset, size_t len);
310static int btrfsic_create_link_to_next_block(
311 struct btrfsic_state *state,
312 struct btrfsic_block *block,
313 struct btrfsic_block_data_ctx
314 *block_ctx, u64 next_bytenr,
315 int limit_nesting,
316 struct btrfsic_block_data_ctx *next_block_ctx,
317 struct btrfsic_block **next_blockp,
318 int force_iodone_flag,
319 int *num_copiesp, int *mirror_nump,
320 struct btrfs_disk_key *disk_key,
321 u64 parent_generation);
322static int btrfsic_handle_extent_data(struct btrfsic_state *state,
323 struct btrfsic_block *block,
324 struct btrfsic_block_data_ctx *block_ctx,
325 u32 item_offset, int force_iodone_flag);
326static int btrfsic_map_block(struct btrfsic_state *state, u64 bytenr, u32 len,
327 struct btrfsic_block_data_ctx *block_ctx_out,
328 int mirror_num);
329static int btrfsic_map_superblock(struct btrfsic_state *state, u64 bytenr,
330 u32 len, struct block_device *bdev,
331 struct btrfsic_block_data_ctx *block_ctx_out);
332static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx);
333static int btrfsic_read_block(struct btrfsic_state *state,
334 struct btrfsic_block_data_ctx *block_ctx);
335static void btrfsic_dump_database(struct btrfsic_state *state);
336static int btrfsic_test_for_metadata(struct btrfsic_state *state,
337 char **datav, unsigned int num_pages);
338static void btrfsic_process_written_block(struct btrfsic_dev_state *dev_state,
339 u64 dev_bytenr, char **mapped_datav,
340 unsigned int num_pages,
341 struct bio *bio, int *bio_is_patched,
342 struct buffer_head *bh,
343 int submit_bio_bh_rw);
344static int btrfsic_process_written_superblock(
345 struct btrfsic_state *state,
346 struct btrfsic_block *const block,
347 struct btrfs_super_block *const super_hdr);
348static void btrfsic_bio_end_io(struct bio *bp, int bio_error_status);
349static void btrfsic_bh_end_io(struct buffer_head *bh, int uptodate);
350static int btrfsic_is_block_ref_by_superblock(const struct btrfsic_state *state,
351 const struct btrfsic_block *block,
352 int recursion_level);
353static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state,
354 struct btrfsic_block *const block,
355 int recursion_level);
356static void btrfsic_print_add_link(const struct btrfsic_state *state,
357 const struct btrfsic_block_link *l);
358static void btrfsic_print_rem_link(const struct btrfsic_state *state,
359 const struct btrfsic_block_link *l);
360static char btrfsic_get_block_type(const struct btrfsic_state *state,
361 const struct btrfsic_block *block);
362static void btrfsic_dump_tree(const struct btrfsic_state *state);
363static void btrfsic_dump_tree_sub(const struct btrfsic_state *state,
364 const struct btrfsic_block *block,
365 int indent_level);
366static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add(
367 struct btrfsic_state *state,
368 struct btrfsic_block_data_ctx *next_block_ctx,
369 struct btrfsic_block *next_block,
370 struct btrfsic_block *from_block,
371 u64 parent_generation);
372static struct btrfsic_block *btrfsic_block_lookup_or_add(
373 struct btrfsic_state *state,
374 struct btrfsic_block_data_ctx *block_ctx,
375 const char *additional_string,
376 int is_metadata,
377 int is_iodone,
378 int never_written,
379 int mirror_num,
380 int *was_created);
381static int btrfsic_process_superblock_dev_mirror(
382 struct btrfsic_state *state,
383 struct btrfsic_dev_state *dev_state,
384 struct btrfs_device *device,
385 int superblock_mirror_num,
386 struct btrfsic_dev_state **selected_dev_state,
387 struct btrfs_super_block *selected_super);
388static struct btrfsic_dev_state *btrfsic_dev_state_lookup(
389 struct block_device *bdev);
390static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state,
391 u64 bytenr,
392 struct btrfsic_dev_state *dev_state,
393 u64 dev_bytenr);
394
395static struct mutex btrfsic_mutex;
396static int btrfsic_is_initialized;
397static struct btrfsic_dev_state_hashtable btrfsic_dev_state_hashtable;
398
399
400static void btrfsic_block_init(struct btrfsic_block *b)
401{
402 b->magic_num = BTRFSIC_BLOCK_MAGIC_NUMBER;
403 b->dev_state = NULL;
404 b->dev_bytenr = 0;
405 b->logical_bytenr = 0;
406 b->generation = BTRFSIC_GENERATION_UNKNOWN;
407 b->disk_key.objectid = 0;
408 b->disk_key.type = 0;
409 b->disk_key.offset = 0;
410 b->is_metadata = 0;
411 b->is_superblock = 0;
412 b->is_iodone = 0;
413 b->iodone_w_error = 0;
414 b->never_written = 0;
415 b->mirror_num = 0;
416 b->next_in_same_bio = NULL;
417 b->orig_bio_bh_private = NULL;
418 b->orig_bio_bh_end_io.bio = NULL;
419 INIT_LIST_HEAD(&b->collision_resolving_node);
420 INIT_LIST_HEAD(&b->all_blocks_node);
421 INIT_LIST_HEAD(&b->ref_to_list);
422 INIT_LIST_HEAD(&b->ref_from_list);
423 b->submit_bio_bh_rw = 0;
424 b->flush_gen = 0;
425}
426
427static struct btrfsic_block *btrfsic_block_alloc(void)
428{
429 struct btrfsic_block *b;
430
431 b = kzalloc(sizeof(*b), GFP_NOFS);
432 if (NULL != b)
433 btrfsic_block_init(b);
434
435 return b;
436}
437
438static void btrfsic_block_free(struct btrfsic_block *b)
439{
440 BUG_ON(!(NULL == b || BTRFSIC_BLOCK_MAGIC_NUMBER == b->magic_num));
441 kfree(b);
442}
443
444static void btrfsic_block_link_init(struct btrfsic_block_link *l)
445{
446 l->magic_num = BTRFSIC_BLOCK_LINK_MAGIC_NUMBER;
447 l->ref_cnt = 1;
448 INIT_LIST_HEAD(&l->node_ref_to);
449 INIT_LIST_HEAD(&l->node_ref_from);
450 INIT_LIST_HEAD(&l->collision_resolving_node);
451 l->block_ref_to = NULL;
452 l->block_ref_from = NULL;
453}
454
455static struct btrfsic_block_link *btrfsic_block_link_alloc(void)
456{
457 struct btrfsic_block_link *l;
458
459 l = kzalloc(sizeof(*l), GFP_NOFS);
460 if (NULL != l)
461 btrfsic_block_link_init(l);
462
463 return l;
464}
465
466static void btrfsic_block_link_free(struct btrfsic_block_link *l)
467{
468 BUG_ON(!(NULL == l || BTRFSIC_BLOCK_LINK_MAGIC_NUMBER == l->magic_num));
469 kfree(l);
470}
471
472static void btrfsic_dev_state_init(struct btrfsic_dev_state *ds)
473{
474 ds->magic_num = BTRFSIC_DEV2STATE_MAGIC_NUMBER;
475 ds->bdev = NULL;
476 ds->state = NULL;
477 ds->name[0] = '\0';
478 INIT_LIST_HEAD(&ds->collision_resolving_node);
479 ds->last_flush_gen = 0;
480 btrfsic_block_init(&ds->dummy_block_for_bio_bh_flush);
481 ds->dummy_block_for_bio_bh_flush.is_iodone = 1;
482 ds->dummy_block_for_bio_bh_flush.dev_state = ds;
483}
484
485static struct btrfsic_dev_state *btrfsic_dev_state_alloc(void)
486{
487 struct btrfsic_dev_state *ds;
488
489 ds = kzalloc(sizeof(*ds), GFP_NOFS);
490 if (NULL != ds)
491 btrfsic_dev_state_init(ds);
492
493 return ds;
494}
495
496static void btrfsic_dev_state_free(struct btrfsic_dev_state *ds)
497{
498 BUG_ON(!(NULL == ds ||
499 BTRFSIC_DEV2STATE_MAGIC_NUMBER == ds->magic_num));
500 kfree(ds);
501}
502
503static void btrfsic_block_hashtable_init(struct btrfsic_block_hashtable *h)
504{
505 int i;
506
507 for (i = 0; i < BTRFSIC_BLOCK_HASHTABLE_SIZE; i++)
508 INIT_LIST_HEAD(h->table + i);
509}
510
511static void btrfsic_block_hashtable_add(struct btrfsic_block *b,
512 struct btrfsic_block_hashtable *h)
513{
514 const unsigned int hashval =
515 (((unsigned int)(b->dev_bytenr >> 16)) ^
516 ((unsigned int)((uintptr_t)b->dev_state->bdev))) &
517 (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1);
518
519 list_add(&b->collision_resolving_node, h->table + hashval);
520}
521
522static void btrfsic_block_hashtable_remove(struct btrfsic_block *b)
523{
524 list_del(&b->collision_resolving_node);
525}
526
527static struct btrfsic_block *btrfsic_block_hashtable_lookup(
528 struct block_device *bdev,
529 u64 dev_bytenr,
530 struct btrfsic_block_hashtable *h)
531{
532 const unsigned int hashval =
533 (((unsigned int)(dev_bytenr >> 16)) ^
534 ((unsigned int)((uintptr_t)bdev))) &
535 (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1);
536 struct list_head *elem;
537
538 list_for_each(elem, h->table + hashval) {
539 struct btrfsic_block *const b =
540 list_entry(elem, struct btrfsic_block,
541 collision_resolving_node);
542
543 if (b->dev_state->bdev == bdev && b->dev_bytenr == dev_bytenr)
544 return b;
545 }
546
547 return NULL;
548}
549
550static void btrfsic_block_link_hashtable_init(
551 struct btrfsic_block_link_hashtable *h)
552{
553 int i;
554
555 for (i = 0; i < BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE; i++)
556 INIT_LIST_HEAD(h->table + i);
557}
558
559static void btrfsic_block_link_hashtable_add(
560 struct btrfsic_block_link *l,
561 struct btrfsic_block_link_hashtable *h)
562{
563 const unsigned int hashval =
564 (((unsigned int)(l->block_ref_to->dev_bytenr >> 16)) ^
565 ((unsigned int)(l->block_ref_from->dev_bytenr >> 16)) ^
566 ((unsigned int)((uintptr_t)l->block_ref_to->dev_state->bdev)) ^
567 ((unsigned int)((uintptr_t)l->block_ref_from->dev_state->bdev)))
568 & (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1);
569
570 BUG_ON(NULL == l->block_ref_to);
571 BUG_ON(NULL == l->block_ref_from);
572 list_add(&l->collision_resolving_node, h->table + hashval);
573}
574
575static void btrfsic_block_link_hashtable_remove(struct btrfsic_block_link *l)
576{
577 list_del(&l->collision_resolving_node);
578}
579
580static struct btrfsic_block_link *btrfsic_block_link_hashtable_lookup(
581 struct block_device *bdev_ref_to,
582 u64 dev_bytenr_ref_to,
583 struct block_device *bdev_ref_from,
584 u64 dev_bytenr_ref_from,
585 struct btrfsic_block_link_hashtable *h)
586{
587 const unsigned int hashval =
588 (((unsigned int)(dev_bytenr_ref_to >> 16)) ^
589 ((unsigned int)(dev_bytenr_ref_from >> 16)) ^
590 ((unsigned int)((uintptr_t)bdev_ref_to)) ^
591 ((unsigned int)((uintptr_t)bdev_ref_from))) &
592 (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1);
593 struct list_head *elem;
594
595 list_for_each(elem, h->table + hashval) {
596 struct btrfsic_block_link *const l =
597 list_entry(elem, struct btrfsic_block_link,
598 collision_resolving_node);
599
600 BUG_ON(NULL == l->block_ref_to);
601 BUG_ON(NULL == l->block_ref_from);
602 if (l->block_ref_to->dev_state->bdev == bdev_ref_to &&
603 l->block_ref_to->dev_bytenr == dev_bytenr_ref_to &&
604 l->block_ref_from->dev_state->bdev == bdev_ref_from &&
605 l->block_ref_from->dev_bytenr == dev_bytenr_ref_from)
606 return l;
607 }
608
609 return NULL;
610}
611
612static void btrfsic_dev_state_hashtable_init(
613 struct btrfsic_dev_state_hashtable *h)
614{
615 int i;
616
617 for (i = 0; i < BTRFSIC_DEV2STATE_HASHTABLE_SIZE; i++)
618 INIT_LIST_HEAD(h->table + i);
619}
620
621static void btrfsic_dev_state_hashtable_add(
622 struct btrfsic_dev_state *ds,
623 struct btrfsic_dev_state_hashtable *h)
624{
625 const unsigned int hashval =
626 (((unsigned int)((uintptr_t)ds->bdev)) &
627 (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1));
628
629 list_add(&ds->collision_resolving_node, h->table + hashval);
630}
631
632static void btrfsic_dev_state_hashtable_remove(struct btrfsic_dev_state *ds)
633{
634 list_del(&ds->collision_resolving_node);
635}
636
637static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(
638 struct block_device *bdev,
639 struct btrfsic_dev_state_hashtable *h)
640{
641 const unsigned int hashval =
642 (((unsigned int)((uintptr_t)bdev)) &
643 (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1));
644 struct list_head *elem;
645
646 list_for_each(elem, h->table + hashval) {
647 struct btrfsic_dev_state *const ds =
648 list_entry(elem, struct btrfsic_dev_state,
649 collision_resolving_node);
650
651 if (ds->bdev == bdev)
652 return ds;
653 }
654
655 return NULL;
656}
657
658static int btrfsic_process_superblock(struct btrfsic_state *state,
659 struct btrfs_fs_devices *fs_devices)
660{
661 int ret = 0;
662 struct btrfs_super_block *selected_super;
663 struct list_head *dev_head = &fs_devices->devices;
664 struct btrfs_device *device;
665 struct btrfsic_dev_state *selected_dev_state = NULL;
666 int pass;
667
668 BUG_ON(NULL == state);
669 selected_super = kzalloc(sizeof(*selected_super), GFP_NOFS);
670 if (NULL == selected_super) {
671 printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
672 return -1;
673 }
674
675 list_for_each_entry(device, dev_head, dev_list) {
676 int i;
677 struct btrfsic_dev_state *dev_state;
678
679 if (!device->bdev || !device->name)
680 continue;
681
682 dev_state = btrfsic_dev_state_lookup(device->bdev);
683 BUG_ON(NULL == dev_state);
684 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
685 ret = btrfsic_process_superblock_dev_mirror(
686 state, dev_state, device, i,
687 &selected_dev_state, selected_super);
688 if (0 != ret && 0 == i) {
689 kfree(selected_super);
690 return ret;
691 }
692 }
693 }
694
695 if (NULL == state->latest_superblock) {
696 printk(KERN_INFO "btrfsic: no superblock found!\n");
697 kfree(selected_super);
698 return -1;
699 }
700
701 state->csum_size = btrfs_super_csum_size(selected_super);
702
703 for (pass = 0; pass < 3; pass++) {
704 int num_copies;
705 int mirror_num;
706 u64 next_bytenr;
707
708 switch (pass) {
709 case 0:
710 next_bytenr = btrfs_super_root(selected_super);
711 if (state->print_mask &
712 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
713 printk(KERN_INFO "root@%llu\n", next_bytenr);
714 break;
715 case 1:
716 next_bytenr = btrfs_super_chunk_root(selected_super);
717 if (state->print_mask &
718 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
719 printk(KERN_INFO "chunk@%llu\n", next_bytenr);
720 break;
721 case 2:
722 next_bytenr = btrfs_super_log_root(selected_super);
723 if (0 == next_bytenr)
724 continue;
725 if (state->print_mask &
726 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
727 printk(KERN_INFO "log@%llu\n", next_bytenr);
728 break;
729 }
730
731 num_copies =
732 btrfs_num_copies(state->root->fs_info,
733 next_bytenr, state->metablock_size);
734 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
735 printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
736 next_bytenr, num_copies);
737
738 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
739 struct btrfsic_block *next_block;
740 struct btrfsic_block_data_ctx tmp_next_block_ctx;
741 struct btrfsic_block_link *l;
742
743 ret = btrfsic_map_block(state, next_bytenr,
744 state->metablock_size,
745 &tmp_next_block_ctx,
746 mirror_num);
747 if (ret) {
748 printk(KERN_INFO "btrfsic:"
749 " btrfsic_map_block(root @%llu,"
750 " mirror %d) failed!\n",
751 next_bytenr, mirror_num);
752 kfree(selected_super);
753 return -1;
754 }
755
756 next_block = btrfsic_block_hashtable_lookup(
757 tmp_next_block_ctx.dev->bdev,
758 tmp_next_block_ctx.dev_bytenr,
759 &state->block_hashtable);
760 BUG_ON(NULL == next_block);
761
762 l = btrfsic_block_link_hashtable_lookup(
763 tmp_next_block_ctx.dev->bdev,
764 tmp_next_block_ctx.dev_bytenr,
765 state->latest_superblock->dev_state->
766 bdev,
767 state->latest_superblock->dev_bytenr,
768 &state->block_link_hashtable);
769 BUG_ON(NULL == l);
770
771 ret = btrfsic_read_block(state, &tmp_next_block_ctx);
772 if (ret < (int)PAGE_CACHE_SIZE) {
773 printk(KERN_INFO
774 "btrfsic: read @logical %llu failed!\n",
775 tmp_next_block_ctx.start);
776 btrfsic_release_block_ctx(&tmp_next_block_ctx);
777 kfree(selected_super);
778 return -1;
779 }
780
781 ret = btrfsic_process_metablock(state,
782 next_block,
783 &tmp_next_block_ctx,
784 BTRFS_MAX_LEVEL + 3, 1);
785 btrfsic_release_block_ctx(&tmp_next_block_ctx);
786 }
787 }
788
789 kfree(selected_super);
790 return ret;
791}
792
793static int btrfsic_process_superblock_dev_mirror(
794 struct btrfsic_state *state,
795 struct btrfsic_dev_state *dev_state,
796 struct btrfs_device *device,
797 int superblock_mirror_num,
798 struct btrfsic_dev_state **selected_dev_state,
799 struct btrfs_super_block *selected_super)
800{
801 struct btrfs_super_block *super_tmp;
802 u64 dev_bytenr;
803 struct buffer_head *bh;
804 struct btrfsic_block *superblock_tmp;
805 int pass;
806 struct block_device *const superblock_bdev = device->bdev;
807
808 /* super block bytenr is always the unmapped device bytenr */
809 dev_bytenr = btrfs_sb_offset(superblock_mirror_num);
810 if (dev_bytenr + BTRFS_SUPER_INFO_SIZE > device->total_bytes)
811 return -1;
812 bh = __bread(superblock_bdev, dev_bytenr / 4096,
813 BTRFS_SUPER_INFO_SIZE);
814 if (NULL == bh)
815 return -1;
816 super_tmp = (struct btrfs_super_block *)
817 (bh->b_data + (dev_bytenr & 4095));
818
819 if (btrfs_super_bytenr(super_tmp) != dev_bytenr ||
820 btrfs_super_magic(super_tmp) != BTRFS_MAGIC ||
821 memcmp(device->uuid, super_tmp->dev_item.uuid, BTRFS_UUID_SIZE) ||
822 btrfs_super_nodesize(super_tmp) != state->metablock_size ||
823 btrfs_super_leafsize(super_tmp) != state->metablock_size ||
824 btrfs_super_sectorsize(super_tmp) != state->datablock_size) {
825 brelse(bh);
826 return 0;
827 }
828
829 superblock_tmp =
830 btrfsic_block_hashtable_lookup(superblock_bdev,
831 dev_bytenr,
832 &state->block_hashtable);
833 if (NULL == superblock_tmp) {
834 superblock_tmp = btrfsic_block_alloc();
835 if (NULL == superblock_tmp) {
836 printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
837 brelse(bh);
838 return -1;
839 }
840 /* for superblock, only the dev_bytenr makes sense */
841 superblock_tmp->dev_bytenr = dev_bytenr;
842 superblock_tmp->dev_state = dev_state;
843 superblock_tmp->logical_bytenr = dev_bytenr;
844 superblock_tmp->generation = btrfs_super_generation(super_tmp);
845 superblock_tmp->is_metadata = 1;
846 superblock_tmp->is_superblock = 1;
847 superblock_tmp->is_iodone = 1;
848 superblock_tmp->never_written = 0;
849 superblock_tmp->mirror_num = 1 + superblock_mirror_num;
850 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
851 printk_in_rcu(KERN_INFO "New initial S-block (bdev %p, %s)"
852 " @%llu (%s/%llu/%d)\n",
853 superblock_bdev,
854 rcu_str_deref(device->name), dev_bytenr,
855 dev_state->name, dev_bytenr,
856 superblock_mirror_num);
857 list_add(&superblock_tmp->all_blocks_node,
858 &state->all_blocks_list);
859 btrfsic_block_hashtable_add(superblock_tmp,
860 &state->block_hashtable);
861 }
862
863 /* select the one with the highest generation field */
864 if (btrfs_super_generation(super_tmp) >
865 state->max_superblock_generation ||
866 0 == state->max_superblock_generation) {
867 memcpy(selected_super, super_tmp, sizeof(*selected_super));
868 *selected_dev_state = dev_state;
869 state->max_superblock_generation =
870 btrfs_super_generation(super_tmp);
871 state->latest_superblock = superblock_tmp;
872 }
873
874 for (pass = 0; pass < 3; pass++) {
875 u64 next_bytenr;
876 int num_copies;
877 int mirror_num;
878 const char *additional_string = NULL;
879 struct btrfs_disk_key tmp_disk_key;
880
881 tmp_disk_key.type = BTRFS_ROOT_ITEM_KEY;
882 tmp_disk_key.offset = 0;
883 switch (pass) {
884 case 0:
885 btrfs_set_disk_key_objectid(&tmp_disk_key,
886 BTRFS_ROOT_TREE_OBJECTID);
887 additional_string = "initial root ";
888 next_bytenr = btrfs_super_root(super_tmp);
889 break;
890 case 1:
891 btrfs_set_disk_key_objectid(&tmp_disk_key,
892 BTRFS_CHUNK_TREE_OBJECTID);
893 additional_string = "initial chunk ";
894 next_bytenr = btrfs_super_chunk_root(super_tmp);
895 break;
896 case 2:
897 btrfs_set_disk_key_objectid(&tmp_disk_key,
898 BTRFS_TREE_LOG_OBJECTID);
899 additional_string = "initial log ";
900 next_bytenr = btrfs_super_log_root(super_tmp);
901 if (0 == next_bytenr)
902 continue;
903 break;
904 }
905
906 num_copies =
907 btrfs_num_copies(state->root->fs_info,
908 next_bytenr, state->metablock_size);
909 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
910 printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
911 next_bytenr, num_copies);
912 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
913 struct btrfsic_block *next_block;
914 struct btrfsic_block_data_ctx tmp_next_block_ctx;
915 struct btrfsic_block_link *l;
916
917 if (btrfsic_map_block(state, next_bytenr,
918 state->metablock_size,
919 &tmp_next_block_ctx,
920 mirror_num)) {
921 printk(KERN_INFO "btrfsic: btrfsic_map_block("
922 "bytenr @%llu, mirror %d) failed!\n",
923 next_bytenr, mirror_num);
924 brelse(bh);
925 return -1;
926 }
927
928 next_block = btrfsic_block_lookup_or_add(
929 state, &tmp_next_block_ctx,
930 additional_string, 1, 1, 0,
931 mirror_num, NULL);
932 if (NULL == next_block) {
933 btrfsic_release_block_ctx(&tmp_next_block_ctx);
934 brelse(bh);
935 return -1;
936 }
937
938 next_block->disk_key = tmp_disk_key;
939 next_block->generation = BTRFSIC_GENERATION_UNKNOWN;
940 l = btrfsic_block_link_lookup_or_add(
941 state, &tmp_next_block_ctx,
942 next_block, superblock_tmp,
943 BTRFSIC_GENERATION_UNKNOWN);
944 btrfsic_release_block_ctx(&tmp_next_block_ctx);
945 if (NULL == l) {
946 brelse(bh);
947 return -1;
948 }
949 }
950 }
951 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_ALL_TREES)
952 btrfsic_dump_tree_sub(state, superblock_tmp, 0);
953
954 brelse(bh);
955 return 0;
956}
957
958static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void)
959{
960 struct btrfsic_stack_frame *sf;
961
962 sf = kzalloc(sizeof(*sf), GFP_NOFS);
963 if (NULL == sf)
964 printk(KERN_INFO "btrfsic: alloc memory failed!\n");
965 else
966 sf->magic = BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER;
967 return sf;
968}
969
970static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf)
971{
972 BUG_ON(!(NULL == sf ||
973 BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER == sf->magic));
974 kfree(sf);
975}
976
977static int btrfsic_process_metablock(
978 struct btrfsic_state *state,
979 struct btrfsic_block *const first_block,
980 struct btrfsic_block_data_ctx *const first_block_ctx,
981 int first_limit_nesting, int force_iodone_flag)
982{
983 struct btrfsic_stack_frame initial_stack_frame = { 0 };
984 struct btrfsic_stack_frame *sf;
985 struct btrfsic_stack_frame *next_stack;
986 struct btrfs_header *const first_hdr =
987 (struct btrfs_header *)first_block_ctx->datav[0];
988
989 BUG_ON(!first_hdr);
990 sf = &initial_stack_frame;
991 sf->error = 0;
992 sf->i = -1;
993 sf->limit_nesting = first_limit_nesting;
994 sf->block = first_block;
995 sf->block_ctx = first_block_ctx;
996 sf->next_block = NULL;
997 sf->hdr = first_hdr;
998 sf->prev = NULL;
999
1000continue_with_new_stack_frame:
1001 sf->block->generation = le64_to_cpu(sf->hdr->generation);
1002 if (0 == sf->hdr->level) {
1003 struct btrfs_leaf *const leafhdr =
1004 (struct btrfs_leaf *)sf->hdr;
1005
1006 if (-1 == sf->i) {
1007 sf->nr = btrfs_stack_header_nritems(&leafhdr->header);
1008
1009 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1010 printk(KERN_INFO
1011 "leaf %llu items %d generation %llu"
1012 " owner %llu\n",
1013 sf->block_ctx->start, sf->nr,
1014 btrfs_stack_header_generation(
1015 &leafhdr->header),
1016 btrfs_stack_header_owner(
1017 &leafhdr->header));
1018 }
1019
1020continue_with_current_leaf_stack_frame:
1021 if (0 == sf->num_copies || sf->mirror_num > sf->num_copies) {
1022 sf->i++;
1023 sf->num_copies = 0;
1024 }
1025
1026 if (sf->i < sf->nr) {
1027 struct btrfs_item disk_item;
1028 u32 disk_item_offset =
1029 (uintptr_t)(leafhdr->items + sf->i) -
1030 (uintptr_t)leafhdr;
1031 struct btrfs_disk_key *disk_key;
1032 u8 type;
1033 u32 item_offset;
1034 u32 item_size;
1035
1036 if (disk_item_offset + sizeof(struct btrfs_item) >
1037 sf->block_ctx->len) {
1038leaf_item_out_of_bounce_error:
1039 printk(KERN_INFO
1040 "btrfsic: leaf item out of bounce at logical %llu, dev %s\n",
1041 sf->block_ctx->start,
1042 sf->block_ctx->dev->name);
1043 goto one_stack_frame_backwards;
1044 }
1045 btrfsic_read_from_block_data(sf->block_ctx,
1046 &disk_item,
1047 disk_item_offset,
1048 sizeof(struct btrfs_item));
1049 item_offset = btrfs_stack_item_offset(&disk_item);
1050 item_size = btrfs_stack_item_size(&disk_item);
1051 disk_key = &disk_item.key;
1052 type = btrfs_disk_key_type(disk_key);
1053
1054 if (BTRFS_ROOT_ITEM_KEY == type) {
1055 struct btrfs_root_item root_item;
1056 u32 root_item_offset;
1057 u64 next_bytenr;
1058
1059 root_item_offset = item_offset +
1060 offsetof(struct btrfs_leaf, items);
1061 if (root_item_offset + item_size >
1062 sf->block_ctx->len)
1063 goto leaf_item_out_of_bounce_error;
1064 btrfsic_read_from_block_data(
1065 sf->block_ctx, &root_item,
1066 root_item_offset,
1067 item_size);
1068 next_bytenr = btrfs_root_bytenr(&root_item);
1069
1070 sf->error =
1071 btrfsic_create_link_to_next_block(
1072 state,
1073 sf->block,
1074 sf->block_ctx,
1075 next_bytenr,
1076 sf->limit_nesting,
1077 &sf->next_block_ctx,
1078 &sf->next_block,
1079 force_iodone_flag,
1080 &sf->num_copies,
1081 &sf->mirror_num,
1082 disk_key,
1083 btrfs_root_generation(
1084 &root_item));
1085 if (sf->error)
1086 goto one_stack_frame_backwards;
1087
1088 if (NULL != sf->next_block) {
1089 struct btrfs_header *const next_hdr =
1090 (struct btrfs_header *)
1091 sf->next_block_ctx.datav[0];
1092
1093 next_stack =
1094 btrfsic_stack_frame_alloc();
1095 if (NULL == next_stack) {
1096 btrfsic_release_block_ctx(
1097 &sf->
1098 next_block_ctx);
1099 goto one_stack_frame_backwards;
1100 }
1101
1102 next_stack->i = -1;
1103 next_stack->block = sf->next_block;
1104 next_stack->block_ctx =
1105 &sf->next_block_ctx;
1106 next_stack->next_block = NULL;
1107 next_stack->hdr = next_hdr;
1108 next_stack->limit_nesting =
1109 sf->limit_nesting - 1;
1110 next_stack->prev = sf;
1111 sf = next_stack;
1112 goto continue_with_new_stack_frame;
1113 }
1114 } else if (BTRFS_EXTENT_DATA_KEY == type &&
1115 state->include_extent_data) {
1116 sf->error = btrfsic_handle_extent_data(
1117 state,
1118 sf->block,
1119 sf->block_ctx,
1120 item_offset,
1121 force_iodone_flag);
1122 if (sf->error)
1123 goto one_stack_frame_backwards;
1124 }
1125
1126 goto continue_with_current_leaf_stack_frame;
1127 }
1128 } else {
1129 struct btrfs_node *const nodehdr = (struct btrfs_node *)sf->hdr;
1130
1131 if (-1 == sf->i) {
1132 sf->nr = btrfs_stack_header_nritems(&nodehdr->header);
1133
1134 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1135 printk(KERN_INFO "node %llu level %d items %d"
1136 " generation %llu owner %llu\n",
1137 sf->block_ctx->start,
1138 nodehdr->header.level, sf->nr,
1139 btrfs_stack_header_generation(
1140 &nodehdr->header),
1141 btrfs_stack_header_owner(
1142 &nodehdr->header));
1143 }
1144
1145continue_with_current_node_stack_frame:
1146 if (0 == sf->num_copies || sf->mirror_num > sf->num_copies) {
1147 sf->i++;
1148 sf->num_copies = 0;
1149 }
1150
1151 if (sf->i < sf->nr) {
1152 struct btrfs_key_ptr key_ptr;
1153 u32 key_ptr_offset;
1154 u64 next_bytenr;
1155
1156 key_ptr_offset = (uintptr_t)(nodehdr->ptrs + sf->i) -
1157 (uintptr_t)nodehdr;
1158 if (key_ptr_offset + sizeof(struct btrfs_key_ptr) >
1159 sf->block_ctx->len) {
1160 printk(KERN_INFO
1161 "btrfsic: node item out of bounce at logical %llu, dev %s\n",
1162 sf->block_ctx->start,
1163 sf->block_ctx->dev->name);
1164 goto one_stack_frame_backwards;
1165 }
1166 btrfsic_read_from_block_data(
1167 sf->block_ctx, &key_ptr, key_ptr_offset,
1168 sizeof(struct btrfs_key_ptr));
1169 next_bytenr = btrfs_stack_key_blockptr(&key_ptr);
1170
1171 sf->error = btrfsic_create_link_to_next_block(
1172 state,
1173 sf->block,
1174 sf->block_ctx,
1175 next_bytenr,
1176 sf->limit_nesting,
1177 &sf->next_block_ctx,
1178 &sf->next_block,
1179 force_iodone_flag,
1180 &sf->num_copies,
1181 &sf->mirror_num,
1182 &key_ptr.key,
1183 btrfs_stack_key_generation(&key_ptr));
1184 if (sf->error)
1185 goto one_stack_frame_backwards;
1186
1187 if (NULL != sf->next_block) {
1188 struct btrfs_header *const next_hdr =
1189 (struct btrfs_header *)
1190 sf->next_block_ctx.datav[0];
1191
1192 next_stack = btrfsic_stack_frame_alloc();
1193 if (NULL == next_stack)
1194 goto one_stack_frame_backwards;
1195
1196 next_stack->i = -1;
1197 next_stack->block = sf->next_block;
1198 next_stack->block_ctx = &sf->next_block_ctx;
1199 next_stack->next_block = NULL;
1200 next_stack->hdr = next_hdr;
1201 next_stack->limit_nesting =
1202 sf->limit_nesting - 1;
1203 next_stack->prev = sf;
1204 sf = next_stack;
1205 goto continue_with_new_stack_frame;
1206 }
1207
1208 goto continue_with_current_node_stack_frame;
1209 }
1210 }
1211
1212one_stack_frame_backwards:
1213 if (NULL != sf->prev) {
1214 struct btrfsic_stack_frame *const prev = sf->prev;
1215
1216 /* the one for the initial block is freed in the caller */
1217 btrfsic_release_block_ctx(sf->block_ctx);
1218
1219 if (sf->error) {
1220 prev->error = sf->error;
1221 btrfsic_stack_frame_free(sf);
1222 sf = prev;
1223 goto one_stack_frame_backwards;
1224 }
1225
1226 btrfsic_stack_frame_free(sf);
1227 sf = prev;
1228 goto continue_with_new_stack_frame;
1229 } else {
1230 BUG_ON(&initial_stack_frame != sf);
1231 }
1232
1233 return sf->error;
1234}
1235
1236static void btrfsic_read_from_block_data(
1237 struct btrfsic_block_data_ctx *block_ctx,
1238 void *dstv, u32 offset, size_t len)
1239{
1240 size_t cur;
1241 size_t offset_in_page;
1242 char *kaddr;
1243 char *dst = (char *)dstv;
1244 size_t start_offset = block_ctx->start & ((u64)PAGE_CACHE_SIZE - 1);
1245 unsigned long i = (start_offset + offset) >> PAGE_CACHE_SHIFT;
1246
1247 WARN_ON(offset + len > block_ctx->len);
1248 offset_in_page = (start_offset + offset) & (PAGE_CACHE_SIZE - 1);
1249
1250 while (len > 0) {
1251 cur = min(len, ((size_t)PAGE_CACHE_SIZE - offset_in_page));
1252 BUG_ON(i >= (block_ctx->len + PAGE_CACHE_SIZE - 1) >>
1253 PAGE_CACHE_SHIFT);
1254 kaddr = block_ctx->datav[i];
1255 memcpy(dst, kaddr + offset_in_page, cur);
1256
1257 dst += cur;
1258 len -= cur;
1259 offset_in_page = 0;
1260 i++;
1261 }
1262}
1263
1264static int btrfsic_create_link_to_next_block(
1265 struct btrfsic_state *state,
1266 struct btrfsic_block *block,
1267 struct btrfsic_block_data_ctx *block_ctx,
1268 u64 next_bytenr,
1269 int limit_nesting,
1270 struct btrfsic_block_data_ctx *next_block_ctx,
1271 struct btrfsic_block **next_blockp,
1272 int force_iodone_flag,
1273 int *num_copiesp, int *mirror_nump,
1274 struct btrfs_disk_key *disk_key,
1275 u64 parent_generation)
1276{
1277 struct btrfsic_block *next_block = NULL;
1278 int ret;
1279 struct btrfsic_block_link *l;
1280 int did_alloc_block_link;
1281 int block_was_created;
1282
1283 *next_blockp = NULL;
1284 if (0 == *num_copiesp) {
1285 *num_copiesp =
1286 btrfs_num_copies(state->root->fs_info,
1287 next_bytenr, state->metablock_size);
1288 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
1289 printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
1290 next_bytenr, *num_copiesp);
1291 *mirror_nump = 1;
1292 }
1293
1294 if (*mirror_nump > *num_copiesp)
1295 return 0;
1296
1297 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1298 printk(KERN_INFO
1299 "btrfsic_create_link_to_next_block(mirror_num=%d)\n",
1300 *mirror_nump);
1301 ret = btrfsic_map_block(state, next_bytenr,
1302 state->metablock_size,
1303 next_block_ctx, *mirror_nump);
1304 if (ret) {
1305 printk(KERN_INFO
1306 "btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n",
1307 next_bytenr, *mirror_nump);
1308 btrfsic_release_block_ctx(next_block_ctx);
1309 *next_blockp = NULL;
1310 return -1;
1311 }
1312
1313 next_block = btrfsic_block_lookup_or_add(state,
1314 next_block_ctx, "referenced ",
1315 1, force_iodone_flag,
1316 !force_iodone_flag,
1317 *mirror_nump,
1318 &block_was_created);
1319 if (NULL == next_block) {
1320 btrfsic_release_block_ctx(next_block_ctx);
1321 *next_blockp = NULL;
1322 return -1;
1323 }
1324 if (block_was_created) {
1325 l = NULL;
1326 next_block->generation = BTRFSIC_GENERATION_UNKNOWN;
1327 } else {
1328 if (next_block->logical_bytenr != next_bytenr &&
1329 !(!next_block->is_metadata &&
1330 0 == next_block->logical_bytenr)) {
1331 printk(KERN_INFO
1332 "Referenced block @%llu (%s/%llu/%d)"
1333 " found in hash table, %c,"
1334 " bytenr mismatch (!= stored %llu).\n",
1335 next_bytenr, next_block_ctx->dev->name,
1336 next_block_ctx->dev_bytenr, *mirror_nump,
1337 btrfsic_get_block_type(state, next_block),
1338 next_block->logical_bytenr);
1339 } else if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1340 printk(KERN_INFO
1341 "Referenced block @%llu (%s/%llu/%d)"
1342 " found in hash table, %c.\n",
1343 next_bytenr, next_block_ctx->dev->name,
1344 next_block_ctx->dev_bytenr, *mirror_nump,
1345 btrfsic_get_block_type(state, next_block));
1346 next_block->logical_bytenr = next_bytenr;
1347
1348 next_block->mirror_num = *mirror_nump;
1349 l = btrfsic_block_link_hashtable_lookup(
1350 next_block_ctx->dev->bdev,
1351 next_block_ctx->dev_bytenr,
1352 block_ctx->dev->bdev,
1353 block_ctx->dev_bytenr,
1354 &state->block_link_hashtable);
1355 }
1356
1357 next_block->disk_key = *disk_key;
1358 if (NULL == l) {
1359 l = btrfsic_block_link_alloc();
1360 if (NULL == l) {
1361 printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
1362 btrfsic_release_block_ctx(next_block_ctx);
1363 *next_blockp = NULL;
1364 return -1;
1365 }
1366
1367 did_alloc_block_link = 1;
1368 l->block_ref_to = next_block;
1369 l->block_ref_from = block;
1370 l->ref_cnt = 1;
1371 l->parent_generation = parent_generation;
1372
1373 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1374 btrfsic_print_add_link(state, l);
1375
1376 list_add(&l->node_ref_to, &block->ref_to_list);
1377 list_add(&l->node_ref_from, &next_block->ref_from_list);
1378
1379 btrfsic_block_link_hashtable_add(l,
1380 &state->block_link_hashtable);
1381 } else {
1382 did_alloc_block_link = 0;
1383 if (0 == limit_nesting) {
1384 l->ref_cnt++;
1385 l->parent_generation = parent_generation;
1386 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1387 btrfsic_print_add_link(state, l);
1388 }
1389 }
1390
1391 if (limit_nesting > 0 && did_alloc_block_link) {
1392 ret = btrfsic_read_block(state, next_block_ctx);
1393 if (ret < (int)next_block_ctx->len) {
1394 printk(KERN_INFO
1395 "btrfsic: read block @logical %llu failed!\n",
1396 next_bytenr);
1397 btrfsic_release_block_ctx(next_block_ctx);
1398 *next_blockp = NULL;
1399 return -1;
1400 }
1401
1402 *next_blockp = next_block;
1403 } else {
1404 *next_blockp = NULL;
1405 }
1406 (*mirror_nump)++;
1407
1408 return 0;
1409}
1410
1411static int btrfsic_handle_extent_data(
1412 struct btrfsic_state *state,
1413 struct btrfsic_block *block,
1414 struct btrfsic_block_data_ctx *block_ctx,
1415 u32 item_offset, int force_iodone_flag)
1416{
1417 int ret;
1418 struct btrfs_file_extent_item file_extent_item;
1419 u64 file_extent_item_offset;
1420 u64 next_bytenr;
1421 u64 num_bytes;
1422 u64 generation;
1423 struct btrfsic_block_link *l;
1424
1425 file_extent_item_offset = offsetof(struct btrfs_leaf, items) +
1426 item_offset;
1427 if (file_extent_item_offset +
1428 offsetof(struct btrfs_file_extent_item, disk_num_bytes) >
1429 block_ctx->len) {
1430 printk(KERN_INFO
1431 "btrfsic: file item out of bounce at logical %llu, dev %s\n",
1432 block_ctx->start, block_ctx->dev->name);
1433 return -1;
1434 }
1435
1436 btrfsic_read_from_block_data(block_ctx, &file_extent_item,
1437 file_extent_item_offset,
1438 offsetof(struct btrfs_file_extent_item, disk_num_bytes));
1439 if (BTRFS_FILE_EXTENT_REG != file_extent_item.type ||
1440 btrfs_stack_file_extent_disk_bytenr(&file_extent_item) == 0) {
1441 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE)
1442 printk(KERN_INFO "extent_data: type %u, disk_bytenr = %llu\n",
1443 file_extent_item.type,
1444 btrfs_stack_file_extent_disk_bytenr(
1445 &file_extent_item));
1446 return 0;
1447 }
1448
1449 if (file_extent_item_offset + sizeof(struct btrfs_file_extent_item) >
1450 block_ctx->len) {
1451 printk(KERN_INFO
1452 "btrfsic: file item out of bounce at logical %llu, dev %s\n",
1453 block_ctx->start, block_ctx->dev->name);
1454 return -1;
1455 }
1456 btrfsic_read_from_block_data(block_ctx, &file_extent_item,
1457 file_extent_item_offset,
1458 sizeof(struct btrfs_file_extent_item));
1459 next_bytenr = btrfs_stack_file_extent_disk_bytenr(&file_extent_item);
1460 if (btrfs_stack_file_extent_compression(&file_extent_item) ==
1461 BTRFS_COMPRESS_NONE) {
1462 next_bytenr += btrfs_stack_file_extent_offset(&file_extent_item);
1463 num_bytes = btrfs_stack_file_extent_num_bytes(&file_extent_item);
1464 } else {
1465 num_bytes = btrfs_stack_file_extent_disk_num_bytes(&file_extent_item);
1466 }
1467 generation = btrfs_stack_file_extent_generation(&file_extent_item);
1468
1469 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE)
1470 printk(KERN_INFO "extent_data: type %u, disk_bytenr = %llu,"
1471 " offset = %llu, num_bytes = %llu\n",
1472 file_extent_item.type,
1473 btrfs_stack_file_extent_disk_bytenr(&file_extent_item),
1474 btrfs_stack_file_extent_offset(&file_extent_item),
1475 num_bytes);
1476 while (num_bytes > 0) {
1477 u32 chunk_len;
1478 int num_copies;
1479 int mirror_num;
1480
1481 if (num_bytes > state->datablock_size)
1482 chunk_len = state->datablock_size;
1483 else
1484 chunk_len = num_bytes;
1485
1486 num_copies =
1487 btrfs_num_copies(state->root->fs_info,
1488 next_bytenr, state->datablock_size);
1489 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
1490 printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
1491 next_bytenr, num_copies);
1492 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
1493 struct btrfsic_block_data_ctx next_block_ctx;
1494 struct btrfsic_block *next_block;
1495 int block_was_created;
1496
1497 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1498 printk(KERN_INFO "btrfsic_handle_extent_data("
1499 "mirror_num=%d)\n", mirror_num);
1500 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE)
1501 printk(KERN_INFO
1502 "\tdisk_bytenr = %llu, num_bytes %u\n",
1503 next_bytenr, chunk_len);
1504 ret = btrfsic_map_block(state, next_bytenr,
1505 chunk_len, &next_block_ctx,
1506 mirror_num);
1507 if (ret) {
1508 printk(KERN_INFO
1509 "btrfsic: btrfsic_map_block(@%llu,"
1510 " mirror=%d) failed!\n",
1511 next_bytenr, mirror_num);
1512 return -1;
1513 }
1514
1515 next_block = btrfsic_block_lookup_or_add(
1516 state,
1517 &next_block_ctx,
1518 "referenced ",
1519 0,
1520 force_iodone_flag,
1521 !force_iodone_flag,
1522 mirror_num,
1523 &block_was_created);
1524 if (NULL == next_block) {
1525 printk(KERN_INFO
1526 "btrfsic: error, kmalloc failed!\n");
1527 btrfsic_release_block_ctx(&next_block_ctx);
1528 return -1;
1529 }
1530 if (!block_was_created) {
1531 if (next_block->logical_bytenr != next_bytenr &&
1532 !(!next_block->is_metadata &&
1533 0 == next_block->logical_bytenr)) {
1534 printk(KERN_INFO
1535 "Referenced block"
1536 " @%llu (%s/%llu/%d)"
1537 " found in hash table, D,"
1538 " bytenr mismatch"
1539 " (!= stored %llu).\n",
1540 next_bytenr,
1541 next_block_ctx.dev->name,
1542 next_block_ctx.dev_bytenr,
1543 mirror_num,
1544 next_block->logical_bytenr);
1545 }
1546 next_block->logical_bytenr = next_bytenr;
1547 next_block->mirror_num = mirror_num;
1548 }
1549
1550 l = btrfsic_block_link_lookup_or_add(state,
1551 &next_block_ctx,
1552 next_block, block,
1553 generation);
1554 btrfsic_release_block_ctx(&next_block_ctx);
1555 if (NULL == l)
1556 return -1;
1557 }
1558
1559 next_bytenr += chunk_len;
1560 num_bytes -= chunk_len;
1561 }
1562
1563 return 0;
1564}
1565
1566static int btrfsic_map_block(struct btrfsic_state *state, u64 bytenr, u32 len,
1567 struct btrfsic_block_data_ctx *block_ctx_out,
1568 int mirror_num)
1569{
1570 int ret;
1571 u64 length;
1572 struct btrfs_bio *multi = NULL;
1573 struct btrfs_device *device;
1574
1575 length = len;
1576 ret = btrfs_map_block(state->root->fs_info, READ,
1577 bytenr, &length, &multi, mirror_num);
1578
1579 if (ret) {
1580 block_ctx_out->start = 0;
1581 block_ctx_out->dev_bytenr = 0;
1582 block_ctx_out->len = 0;
1583 block_ctx_out->dev = NULL;
1584 block_ctx_out->datav = NULL;
1585 block_ctx_out->pagev = NULL;
1586 block_ctx_out->mem_to_free = NULL;
1587
1588 return ret;
1589 }
1590
1591 device = multi->stripes[0].dev;
1592 block_ctx_out->dev = btrfsic_dev_state_lookup(device->bdev);
1593 block_ctx_out->dev_bytenr = multi->stripes[0].physical;
1594 block_ctx_out->start = bytenr;
1595 block_ctx_out->len = len;
1596 block_ctx_out->datav = NULL;
1597 block_ctx_out->pagev = NULL;
1598 block_ctx_out->mem_to_free = NULL;
1599
1600 kfree(multi);
1601 if (NULL == block_ctx_out->dev) {
1602 ret = -ENXIO;
1603 printk(KERN_INFO "btrfsic: error, cannot lookup dev (#1)!\n");
1604 }
1605
1606 return ret;
1607}
1608
1609static int btrfsic_map_superblock(struct btrfsic_state *state, u64 bytenr,
1610 u32 len, struct block_device *bdev,
1611 struct btrfsic_block_data_ctx *block_ctx_out)
1612{
1613 block_ctx_out->dev = btrfsic_dev_state_lookup(bdev);
1614 block_ctx_out->dev_bytenr = bytenr;
1615 block_ctx_out->start = bytenr;
1616 block_ctx_out->len = len;
1617 block_ctx_out->datav = NULL;
1618 block_ctx_out->pagev = NULL;
1619 block_ctx_out->mem_to_free = NULL;
1620 if (NULL != block_ctx_out->dev) {
1621 return 0;
1622 } else {
1623 printk(KERN_INFO "btrfsic: error, cannot lookup dev (#2)!\n");
1624 return -ENXIO;
1625 }
1626}
1627
1628static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx)
1629{
1630 if (block_ctx->mem_to_free) {
1631 unsigned int num_pages;
1632
1633 BUG_ON(!block_ctx->datav);
1634 BUG_ON(!block_ctx->pagev);
1635 num_pages = (block_ctx->len + (u64)PAGE_CACHE_SIZE - 1) >>
1636 PAGE_CACHE_SHIFT;
1637 while (num_pages > 0) {
1638 num_pages--;
1639 if (block_ctx->datav[num_pages]) {
1640 kunmap(block_ctx->pagev[num_pages]);
1641 block_ctx->datav[num_pages] = NULL;
1642 }
1643 if (block_ctx->pagev[num_pages]) {
1644 __free_page(block_ctx->pagev[num_pages]);
1645 block_ctx->pagev[num_pages] = NULL;
1646 }
1647 }
1648
1649 kfree(block_ctx->mem_to_free);
1650 block_ctx->mem_to_free = NULL;
1651 block_ctx->pagev = NULL;
1652 block_ctx->datav = NULL;
1653 }
1654}
1655
1656static int btrfsic_read_block(struct btrfsic_state *state,
1657 struct btrfsic_block_data_ctx *block_ctx)
1658{
1659 unsigned int num_pages;
1660 unsigned int i;
1661 u64 dev_bytenr;
1662 int ret;
1663
1664 BUG_ON(block_ctx->datav);
1665 BUG_ON(block_ctx->pagev);
1666 BUG_ON(block_ctx->mem_to_free);
1667 if (block_ctx->dev_bytenr & ((u64)PAGE_CACHE_SIZE - 1)) {
1668 printk(KERN_INFO
1669 "btrfsic: read_block() with unaligned bytenr %llu\n",
1670 block_ctx->dev_bytenr);
1671 return -1;
1672 }
1673
1674 num_pages = (block_ctx->len + (u64)PAGE_CACHE_SIZE - 1) >>
1675 PAGE_CACHE_SHIFT;
1676 block_ctx->mem_to_free = kzalloc((sizeof(*block_ctx->datav) +
1677 sizeof(*block_ctx->pagev)) *
1678 num_pages, GFP_NOFS);
1679 if (!block_ctx->mem_to_free)
1680 return -1;
1681 block_ctx->datav = block_ctx->mem_to_free;
1682 block_ctx->pagev = (struct page **)(block_ctx->datav + num_pages);
1683 for (i = 0; i < num_pages; i++) {
1684 block_ctx->pagev[i] = alloc_page(GFP_NOFS);
1685 if (!block_ctx->pagev[i])
1686 return -1;
1687 }
1688
1689 dev_bytenr = block_ctx->dev_bytenr;
1690 for (i = 0; i < num_pages;) {
1691 struct bio *bio;
1692 unsigned int j;
1693
1694 bio = btrfs_io_bio_alloc(GFP_NOFS, num_pages - i);
1695 if (!bio) {
1696 printk(KERN_INFO
1697 "btrfsic: bio_alloc() for %u pages failed!\n",
1698 num_pages - i);
1699 return -1;
1700 }
1701 bio->bi_bdev = block_ctx->dev->bdev;
1702 bio->bi_iter.bi_sector = dev_bytenr >> 9;
1703
1704 for (j = i; j < num_pages; j++) {
1705 ret = bio_add_page(bio, block_ctx->pagev[j],
1706 PAGE_CACHE_SIZE, 0);
1707 if (PAGE_CACHE_SIZE != ret)
1708 break;
1709 }
1710 if (j == i) {
1711 printk(KERN_INFO
1712 "btrfsic: error, failed to add a single page!\n");
1713 return -1;
1714 }
1715 if (submit_bio_wait(READ, bio)) {
1716 printk(KERN_INFO
1717 "btrfsic: read error at logical %llu dev %s!\n",
1718 block_ctx->start, block_ctx->dev->name);
1719 bio_put(bio);
1720 return -1;
1721 }
1722 bio_put(bio);
1723 dev_bytenr += (j - i) * PAGE_CACHE_SIZE;
1724 i = j;
1725 }
1726 for (i = 0; i < num_pages; i++) {
1727 block_ctx->datav[i] = kmap(block_ctx->pagev[i]);
1728 if (!block_ctx->datav[i]) {
1729 printk(KERN_INFO "btrfsic: kmap() failed (dev %s)!\n",
1730 block_ctx->dev->name);
1731 return -1;
1732 }
1733 }
1734
1735 return block_ctx->len;
1736}
1737
1738static void btrfsic_dump_database(struct btrfsic_state *state)
1739{
1740 struct list_head *elem_all;
1741
1742 BUG_ON(NULL == state);
1743
1744 printk(KERN_INFO "all_blocks_list:\n");
1745 list_for_each(elem_all, &state->all_blocks_list) {
1746 const struct btrfsic_block *const b_all =
1747 list_entry(elem_all, struct btrfsic_block,
1748 all_blocks_node);
1749 struct list_head *elem_ref_to;
1750 struct list_head *elem_ref_from;
1751
1752 printk(KERN_INFO "%c-block @%llu (%s/%llu/%d)\n",
1753 btrfsic_get_block_type(state, b_all),
1754 b_all->logical_bytenr, b_all->dev_state->name,
1755 b_all->dev_bytenr, b_all->mirror_num);
1756
1757 list_for_each(elem_ref_to, &b_all->ref_to_list) {
1758 const struct btrfsic_block_link *const l =
1759 list_entry(elem_ref_to,
1760 struct btrfsic_block_link,
1761 node_ref_to);
1762
1763 printk(KERN_INFO " %c @%llu (%s/%llu/%d)"
1764 " refers %u* to"
1765 " %c @%llu (%s/%llu/%d)\n",
1766 btrfsic_get_block_type(state, b_all),
1767 b_all->logical_bytenr, b_all->dev_state->name,
1768 b_all->dev_bytenr, b_all->mirror_num,
1769 l->ref_cnt,
1770 btrfsic_get_block_type(state, l->block_ref_to),
1771 l->block_ref_to->logical_bytenr,
1772 l->block_ref_to->dev_state->name,
1773 l->block_ref_to->dev_bytenr,
1774 l->block_ref_to->mirror_num);
1775 }
1776
1777 list_for_each(elem_ref_from, &b_all->ref_from_list) {
1778 const struct btrfsic_block_link *const l =
1779 list_entry(elem_ref_from,
1780 struct btrfsic_block_link,
1781 node_ref_from);
1782
1783 printk(KERN_INFO " %c @%llu (%s/%llu/%d)"
1784 " is ref %u* from"
1785 " %c @%llu (%s/%llu/%d)\n",
1786 btrfsic_get_block_type(state, b_all),
1787 b_all->logical_bytenr, b_all->dev_state->name,
1788 b_all->dev_bytenr, b_all->mirror_num,
1789 l->ref_cnt,
1790 btrfsic_get_block_type(state, l->block_ref_from),
1791 l->block_ref_from->logical_bytenr,
1792 l->block_ref_from->dev_state->name,
1793 l->block_ref_from->dev_bytenr,
1794 l->block_ref_from->mirror_num);
1795 }
1796
1797 printk(KERN_INFO "\n");
1798 }
1799}
1800
1801/*
1802 * Test whether the disk block contains a tree block (leaf or node)
1803 * (note that this test fails for the super block)
1804 */
1805static int btrfsic_test_for_metadata(struct btrfsic_state *state,
1806 char **datav, unsigned int num_pages)
1807{
1808 struct btrfs_header *h;
1809 u8 csum[BTRFS_CSUM_SIZE];
1810 u32 crc = ~(u32)0;
1811 unsigned int i;
1812
1813 if (num_pages * PAGE_CACHE_SIZE < state->metablock_size)
1814 return 1; /* not metadata */
1815 num_pages = state->metablock_size >> PAGE_CACHE_SHIFT;
1816 h = (struct btrfs_header *)datav[0];
1817
1818 if (memcmp(h->fsid, state->root->fs_info->fsid, BTRFS_UUID_SIZE))
1819 return 1;
1820
1821 for (i = 0; i < num_pages; i++) {
1822 u8 *data = i ? datav[i] : (datav[i] + BTRFS_CSUM_SIZE);
1823 size_t sublen = i ? PAGE_CACHE_SIZE :
1824 (PAGE_CACHE_SIZE - BTRFS_CSUM_SIZE);
1825
1826 crc = btrfs_crc32c(crc, data, sublen);
1827 }
1828 btrfs_csum_final(crc, csum);
1829 if (memcmp(csum, h->csum, state->csum_size))
1830 return 1;
1831
1832 return 0; /* is metadata */
1833}
1834
1835static void btrfsic_process_written_block(struct btrfsic_dev_state *dev_state,
1836 u64 dev_bytenr, char **mapped_datav,
1837 unsigned int num_pages,
1838 struct bio *bio, int *bio_is_patched,
1839 struct buffer_head *bh,
1840 int submit_bio_bh_rw)
1841{
1842 int is_metadata;
1843 struct btrfsic_block *block;
1844 struct btrfsic_block_data_ctx block_ctx;
1845 int ret;
1846 struct btrfsic_state *state = dev_state->state;
1847 struct block_device *bdev = dev_state->bdev;
1848 unsigned int processed_len;
1849
1850 if (NULL != bio_is_patched)
1851 *bio_is_patched = 0;
1852
1853again:
1854 if (num_pages == 0)
1855 return;
1856
1857 processed_len = 0;
1858 is_metadata = (0 == btrfsic_test_for_metadata(state, mapped_datav,
1859 num_pages));
1860
1861 block = btrfsic_block_hashtable_lookup(bdev, dev_bytenr,
1862 &state->block_hashtable);
1863 if (NULL != block) {
1864 u64 bytenr = 0;
1865 struct list_head *elem_ref_to;
1866 struct list_head *tmp_ref_to;
1867
1868 if (block->is_superblock) {
1869 bytenr = btrfs_super_bytenr((struct btrfs_super_block *)
1870 mapped_datav[0]);
1871 if (num_pages * PAGE_CACHE_SIZE <
1872 BTRFS_SUPER_INFO_SIZE) {
1873 printk(KERN_INFO
1874 "btrfsic: cannot work with too short bios!\n");
1875 return;
1876 }
1877 is_metadata = 1;
1878 BUG_ON(BTRFS_SUPER_INFO_SIZE & (PAGE_CACHE_SIZE - 1));
1879 processed_len = BTRFS_SUPER_INFO_SIZE;
1880 if (state->print_mask &
1881 BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE) {
1882 printk(KERN_INFO
1883 "[before new superblock is written]:\n");
1884 btrfsic_dump_tree_sub(state, block, 0);
1885 }
1886 }
1887 if (is_metadata) {
1888 if (!block->is_superblock) {
1889 if (num_pages * PAGE_CACHE_SIZE <
1890 state->metablock_size) {
1891 printk(KERN_INFO
1892 "btrfsic: cannot work with too short bios!\n");
1893 return;
1894 }
1895 processed_len = state->metablock_size;
1896 bytenr = btrfs_stack_header_bytenr(
1897 (struct btrfs_header *)
1898 mapped_datav[0]);
1899 btrfsic_cmp_log_and_dev_bytenr(state, bytenr,
1900 dev_state,
1901 dev_bytenr);
1902 }
1903 if (block->logical_bytenr != bytenr &&
1904 !(!block->is_metadata &&
1905 block->logical_bytenr == 0))
1906 printk(KERN_INFO
1907 "Written block @%llu (%s/%llu/%d)"
1908 " found in hash table, %c,"
1909 " bytenr mismatch"
1910 " (!= stored %llu).\n",
1911 bytenr, dev_state->name, dev_bytenr,
1912 block->mirror_num,
1913 btrfsic_get_block_type(state, block),
1914 block->logical_bytenr);
1915 else if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1916 printk(KERN_INFO
1917 "Written block @%llu (%s/%llu/%d)"
1918 " found in hash table, %c.\n",
1919 bytenr, dev_state->name, dev_bytenr,
1920 block->mirror_num,
1921 btrfsic_get_block_type(state, block));
1922 block->logical_bytenr = bytenr;
1923 } else {
1924 if (num_pages * PAGE_CACHE_SIZE <
1925 state->datablock_size) {
1926 printk(KERN_INFO
1927 "btrfsic: cannot work with too short bios!\n");
1928 return;
1929 }
1930 processed_len = state->datablock_size;
1931 bytenr = block->logical_bytenr;
1932 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1933 printk(KERN_INFO
1934 "Written block @%llu (%s/%llu/%d)"
1935 " found in hash table, %c.\n",
1936 bytenr, dev_state->name, dev_bytenr,
1937 block->mirror_num,
1938 btrfsic_get_block_type(state, block));
1939 }
1940
1941 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1942 printk(KERN_INFO
1943 "ref_to_list: %cE, ref_from_list: %cE\n",
1944 list_empty(&block->ref_to_list) ? ' ' : '!',
1945 list_empty(&block->ref_from_list) ? ' ' : '!');
1946 if (btrfsic_is_block_ref_by_superblock(state, block, 0)) {
1947 printk(KERN_INFO "btrfs: attempt to overwrite %c-block"
1948 " @%llu (%s/%llu/%d), old(gen=%llu,"
1949 " objectid=%llu, type=%d, offset=%llu),"
1950 " new(gen=%llu),"
1951 " which is referenced by most recent superblock"
1952 " (superblockgen=%llu)!\n",
1953 btrfsic_get_block_type(state, block), bytenr,
1954 dev_state->name, dev_bytenr, block->mirror_num,
1955 block->generation,
1956 btrfs_disk_key_objectid(&block->disk_key),
1957 block->disk_key.type,
1958 btrfs_disk_key_offset(&block->disk_key),
1959 btrfs_stack_header_generation(
1960 (struct btrfs_header *) mapped_datav[0]),
1961 state->max_superblock_generation);
1962 btrfsic_dump_tree(state);
1963 }
1964
1965 if (!block->is_iodone && !block->never_written) {
1966 printk(KERN_INFO "btrfs: attempt to overwrite %c-block"
1967 " @%llu (%s/%llu/%d), oldgen=%llu, newgen=%llu,"
1968 " which is not yet iodone!\n",
1969 btrfsic_get_block_type(state, block), bytenr,
1970 dev_state->name, dev_bytenr, block->mirror_num,
1971 block->generation,
1972 btrfs_stack_header_generation(
1973 (struct btrfs_header *)
1974 mapped_datav[0]));
1975 /* it would not be safe to go on */
1976 btrfsic_dump_tree(state);
1977 goto continue_loop;
1978 }
1979
1980 /*
1981 * Clear all references of this block. Do not free
1982 * the block itself even if is not referenced anymore
1983 * because it still carries valueable information
1984 * like whether it was ever written and IO completed.
1985 */
1986 list_for_each_safe(elem_ref_to, tmp_ref_to,
1987 &block->ref_to_list) {
1988 struct btrfsic_block_link *const l =
1989 list_entry(elem_ref_to,
1990 struct btrfsic_block_link,
1991 node_ref_to);
1992
1993 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1994 btrfsic_print_rem_link(state, l);
1995 l->ref_cnt--;
1996 if (0 == l->ref_cnt) {
1997 list_del(&l->node_ref_to);
1998 list_del(&l->node_ref_from);
1999 btrfsic_block_link_hashtable_remove(l);
2000 btrfsic_block_link_free(l);
2001 }
2002 }
2003
2004 if (block->is_superblock)
2005 ret = btrfsic_map_superblock(state, bytenr,
2006 processed_len,
2007 bdev, &block_ctx);
2008 else
2009 ret = btrfsic_map_block(state, bytenr, processed_len,
2010 &block_ctx, 0);
2011 if (ret) {
2012 printk(KERN_INFO
2013 "btrfsic: btrfsic_map_block(root @%llu)"
2014 " failed!\n", bytenr);
2015 goto continue_loop;
2016 }
2017 block_ctx.datav = mapped_datav;
2018 /* the following is required in case of writes to mirrors,
2019 * use the same that was used for the lookup */
2020 block_ctx.dev = dev_state;
2021 block_ctx.dev_bytenr = dev_bytenr;
2022
2023 if (is_metadata || state->include_extent_data) {
2024 block->never_written = 0;
2025 block->iodone_w_error = 0;
2026 if (NULL != bio) {
2027 block->is_iodone = 0;
2028 BUG_ON(NULL == bio_is_patched);
2029 if (!*bio_is_patched) {
2030 block->orig_bio_bh_private =
2031 bio->bi_private;
2032 block->orig_bio_bh_end_io.bio =
2033 bio->bi_end_io;
2034 block->next_in_same_bio = NULL;
2035 bio->bi_private = block;
2036 bio->bi_end_io = btrfsic_bio_end_io;
2037 *bio_is_patched = 1;
2038 } else {
2039 struct btrfsic_block *chained_block =
2040 (struct btrfsic_block *)
2041 bio->bi_private;
2042
2043 BUG_ON(NULL == chained_block);
2044 block->orig_bio_bh_private =
2045 chained_block->orig_bio_bh_private;
2046 block->orig_bio_bh_end_io.bio =
2047 chained_block->orig_bio_bh_end_io.
2048 bio;
2049 block->next_in_same_bio = chained_block;
2050 bio->bi_private = block;
2051 }
2052 } else if (NULL != bh) {
2053 block->is_iodone = 0;
2054 block->orig_bio_bh_private = bh->b_private;
2055 block->orig_bio_bh_end_io.bh = bh->b_end_io;
2056 block->next_in_same_bio = NULL;
2057 bh->b_private = block;
2058 bh->b_end_io = btrfsic_bh_end_io;
2059 } else {
2060 block->is_iodone = 1;
2061 block->orig_bio_bh_private = NULL;
2062 block->orig_bio_bh_end_io.bio = NULL;
2063 block->next_in_same_bio = NULL;
2064 }
2065 }
2066
2067 block->flush_gen = dev_state->last_flush_gen + 1;
2068 block->submit_bio_bh_rw = submit_bio_bh_rw;
2069 if (is_metadata) {
2070 block->logical_bytenr = bytenr;
2071 block->is_metadata = 1;
2072 if (block->is_superblock) {
2073 BUG_ON(PAGE_CACHE_SIZE !=
2074 BTRFS_SUPER_INFO_SIZE);
2075 ret = btrfsic_process_written_superblock(
2076 state,
2077 block,
2078 (struct btrfs_super_block *)
2079 mapped_datav[0]);
2080 if (state->print_mask &
2081 BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE) {
2082 printk(KERN_INFO
2083 "[after new superblock is written]:\n");
2084 btrfsic_dump_tree_sub(state, block, 0);
2085 }
2086 } else {
2087 block->mirror_num = 0; /* unknown */
2088 ret = btrfsic_process_metablock(
2089 state,
2090 block,
2091 &block_ctx,
2092 0, 0);
2093 }
2094 if (ret)
2095 printk(KERN_INFO
2096 "btrfsic: btrfsic_process_metablock"
2097 "(root @%llu) failed!\n",
2098 dev_bytenr);
2099 } else {
2100 block->is_metadata = 0;
2101 block->mirror_num = 0; /* unknown */
2102 block->generation = BTRFSIC_GENERATION_UNKNOWN;
2103 if (!state->include_extent_data
2104 && list_empty(&block->ref_from_list)) {
2105 /*
2106 * disk block is overwritten with extent
2107 * data (not meta data) and we are configured
2108 * to not include extent data: take the
2109 * chance and free the block's memory
2110 */
2111 btrfsic_block_hashtable_remove(block);
2112 list_del(&block->all_blocks_node);
2113 btrfsic_block_free(block);
2114 }
2115 }
2116 btrfsic_release_block_ctx(&block_ctx);
2117 } else {
2118 /* block has not been found in hash table */
2119 u64 bytenr;
2120
2121 if (!is_metadata) {
2122 processed_len = state->datablock_size;
2123 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2124 printk(KERN_INFO "Written block (%s/%llu/?)"
2125 " !found in hash table, D.\n",
2126 dev_state->name, dev_bytenr);
2127 if (!state->include_extent_data) {
2128 /* ignore that written D block */
2129 goto continue_loop;
2130 }
2131
2132 /* this is getting ugly for the
2133 * include_extent_data case... */
2134 bytenr = 0; /* unknown */
2135 block_ctx.start = bytenr;
2136 block_ctx.len = processed_len;
2137 block_ctx.mem_to_free = NULL;
2138 block_ctx.pagev = NULL;
2139 } else {
2140 processed_len = state->metablock_size;
2141 bytenr = btrfs_stack_header_bytenr(
2142 (struct btrfs_header *)
2143 mapped_datav[0]);
2144 btrfsic_cmp_log_and_dev_bytenr(state, bytenr, dev_state,
2145 dev_bytenr);
2146 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2147 printk(KERN_INFO
2148 "Written block @%llu (%s/%llu/?)"
2149 " !found in hash table, M.\n",
2150 bytenr, dev_state->name, dev_bytenr);
2151
2152 ret = btrfsic_map_block(state, bytenr, processed_len,
2153 &block_ctx, 0);
2154 if (ret) {
2155 printk(KERN_INFO
2156 "btrfsic: btrfsic_map_block(root @%llu)"
2157 " failed!\n",
2158 dev_bytenr);
2159 goto continue_loop;
2160 }
2161 }
2162 block_ctx.datav = mapped_datav;
2163 /* the following is required in case of writes to mirrors,
2164 * use the same that was used for the lookup */
2165 block_ctx.dev = dev_state;
2166 block_ctx.dev_bytenr = dev_bytenr;
2167
2168 block = btrfsic_block_alloc();
2169 if (NULL == block) {
2170 printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
2171 btrfsic_release_block_ctx(&block_ctx);
2172 goto continue_loop;
2173 }
2174 block->dev_state = dev_state;
2175 block->dev_bytenr = dev_bytenr;
2176 block->logical_bytenr = bytenr;
2177 block->is_metadata = is_metadata;
2178 block->never_written = 0;
2179 block->iodone_w_error = 0;
2180 block->mirror_num = 0; /* unknown */
2181 block->flush_gen = dev_state->last_flush_gen + 1;
2182 block->submit_bio_bh_rw = submit_bio_bh_rw;
2183 if (NULL != bio) {
2184 block->is_iodone = 0;
2185 BUG_ON(NULL == bio_is_patched);
2186 if (!*bio_is_patched) {
2187 block->orig_bio_bh_private = bio->bi_private;
2188 block->orig_bio_bh_end_io.bio = bio->bi_end_io;
2189 block->next_in_same_bio = NULL;
2190 bio->bi_private = block;
2191 bio->bi_end_io = btrfsic_bio_end_io;
2192 *bio_is_patched = 1;
2193 } else {
2194 struct btrfsic_block *chained_block =
2195 (struct btrfsic_block *)
2196 bio->bi_private;
2197
2198 BUG_ON(NULL == chained_block);
2199 block->orig_bio_bh_private =
2200 chained_block->orig_bio_bh_private;
2201 block->orig_bio_bh_end_io.bio =
2202 chained_block->orig_bio_bh_end_io.bio;
2203 block->next_in_same_bio = chained_block;
2204 bio->bi_private = block;
2205 }
2206 } else if (NULL != bh) {
2207 block->is_iodone = 0;
2208 block->orig_bio_bh_private = bh->b_private;
2209 block->orig_bio_bh_end_io.bh = bh->b_end_io;
2210 block->next_in_same_bio = NULL;
2211 bh->b_private = block;
2212 bh->b_end_io = btrfsic_bh_end_io;
2213 } else {
2214 block->is_iodone = 1;
2215 block->orig_bio_bh_private = NULL;
2216 block->orig_bio_bh_end_io.bio = NULL;
2217 block->next_in_same_bio = NULL;
2218 }
2219 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2220 printk(KERN_INFO
2221 "New written %c-block @%llu (%s/%llu/%d)\n",
2222 is_metadata ? 'M' : 'D',
2223 block->logical_bytenr, block->dev_state->name,
2224 block->dev_bytenr, block->mirror_num);
2225 list_add(&block->all_blocks_node, &state->all_blocks_list);
2226 btrfsic_block_hashtable_add(block, &state->block_hashtable);
2227
2228 if (is_metadata) {
2229 ret = btrfsic_process_metablock(state, block,
2230 &block_ctx, 0, 0);
2231 if (ret)
2232 printk(KERN_INFO
2233 "btrfsic: process_metablock(root @%llu)"
2234 " failed!\n",
2235 dev_bytenr);
2236 }
2237 btrfsic_release_block_ctx(&block_ctx);
2238 }
2239
2240continue_loop:
2241 BUG_ON(!processed_len);
2242 dev_bytenr += processed_len;
2243 mapped_datav += processed_len >> PAGE_CACHE_SHIFT;
2244 num_pages -= processed_len >> PAGE_CACHE_SHIFT;
2245 goto again;
2246}
2247
2248static void btrfsic_bio_end_io(struct bio *bp, int bio_error_status)
2249{
2250 struct btrfsic_block *block = (struct btrfsic_block *)bp->bi_private;
2251 int iodone_w_error;
2252
2253 /* mutex is not held! This is not save if IO is not yet completed
2254 * on umount */
2255 iodone_w_error = 0;
2256 if (bio_error_status)
2257 iodone_w_error = 1;
2258
2259 BUG_ON(NULL == block);
2260 bp->bi_private = block->orig_bio_bh_private;
2261 bp->bi_end_io = block->orig_bio_bh_end_io.bio;
2262
2263 do {
2264 struct btrfsic_block *next_block;
2265 struct btrfsic_dev_state *const dev_state = block->dev_state;
2266
2267 if ((dev_state->state->print_mask &
2268 BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
2269 printk(KERN_INFO
2270 "bio_end_io(err=%d) for %c @%llu (%s/%llu/%d)\n",
2271 bio_error_status,
2272 btrfsic_get_block_type(dev_state->state, block),
2273 block->logical_bytenr, dev_state->name,
2274 block->dev_bytenr, block->mirror_num);
2275 next_block = block->next_in_same_bio;
2276 block->iodone_w_error = iodone_w_error;
2277 if (block->submit_bio_bh_rw & REQ_FLUSH) {
2278 dev_state->last_flush_gen++;
2279 if ((dev_state->state->print_mask &
2280 BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
2281 printk(KERN_INFO
2282 "bio_end_io() new %s flush_gen=%llu\n",
2283 dev_state->name,
2284 dev_state->last_flush_gen);
2285 }
2286 if (block->submit_bio_bh_rw & REQ_FUA)
2287 block->flush_gen = 0; /* FUA completed means block is
2288 * on disk */
2289 block->is_iodone = 1; /* for FLUSH, this releases the block */
2290 block = next_block;
2291 } while (NULL != block);
2292
2293 bp->bi_end_io(bp, bio_error_status);
2294}
2295
2296static void btrfsic_bh_end_io(struct buffer_head *bh, int uptodate)
2297{
2298 struct btrfsic_block *block = (struct btrfsic_block *)bh->b_private;
2299 int iodone_w_error = !uptodate;
2300 struct btrfsic_dev_state *dev_state;
2301
2302 BUG_ON(NULL == block);
2303 dev_state = block->dev_state;
2304 if ((dev_state->state->print_mask & BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
2305 printk(KERN_INFO
2306 "bh_end_io(error=%d) for %c @%llu (%s/%llu/%d)\n",
2307 iodone_w_error,
2308 btrfsic_get_block_type(dev_state->state, block),
2309 block->logical_bytenr, block->dev_state->name,
2310 block->dev_bytenr, block->mirror_num);
2311
2312 block->iodone_w_error = iodone_w_error;
2313 if (block->submit_bio_bh_rw & REQ_FLUSH) {
2314 dev_state->last_flush_gen++;
2315 if ((dev_state->state->print_mask &
2316 BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
2317 printk(KERN_INFO
2318 "bh_end_io() new %s flush_gen=%llu\n",
2319 dev_state->name, dev_state->last_flush_gen);
2320 }
2321 if (block->submit_bio_bh_rw & REQ_FUA)
2322 block->flush_gen = 0; /* FUA completed means block is on disk */
2323
2324 bh->b_private = block->orig_bio_bh_private;
2325 bh->b_end_io = block->orig_bio_bh_end_io.bh;
2326 block->is_iodone = 1; /* for FLUSH, this releases the block */
2327 bh->b_end_io(bh, uptodate);
2328}
2329
2330static int btrfsic_process_written_superblock(
2331 struct btrfsic_state *state,
2332 struct btrfsic_block *const superblock,
2333 struct btrfs_super_block *const super_hdr)
2334{
2335 int pass;
2336
2337 superblock->generation = btrfs_super_generation(super_hdr);
2338 if (!(superblock->generation > state->max_superblock_generation ||
2339 0 == state->max_superblock_generation)) {
2340 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
2341 printk(KERN_INFO
2342 "btrfsic: superblock @%llu (%s/%llu/%d)"
2343 " with old gen %llu <= %llu\n",
2344 superblock->logical_bytenr,
2345 superblock->dev_state->name,
2346 superblock->dev_bytenr, superblock->mirror_num,
2347 btrfs_super_generation(super_hdr),
2348 state->max_superblock_generation);
2349 } else {
2350 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
2351 printk(KERN_INFO
2352 "btrfsic: got new superblock @%llu (%s/%llu/%d)"
2353 " with new gen %llu > %llu\n",
2354 superblock->logical_bytenr,
2355 superblock->dev_state->name,
2356 superblock->dev_bytenr, superblock->mirror_num,
2357 btrfs_super_generation(super_hdr),
2358 state->max_superblock_generation);
2359
2360 state->max_superblock_generation =
2361 btrfs_super_generation(super_hdr);
2362 state->latest_superblock = superblock;
2363 }
2364
2365 for (pass = 0; pass < 3; pass++) {
2366 int ret;
2367 u64 next_bytenr;
2368 struct btrfsic_block *next_block;
2369 struct btrfsic_block_data_ctx tmp_next_block_ctx;
2370 struct btrfsic_block_link *l;
2371 int num_copies;
2372 int mirror_num;
2373 const char *additional_string = NULL;
2374 struct btrfs_disk_key tmp_disk_key = {0};
2375
2376 btrfs_set_disk_key_objectid(&tmp_disk_key,
2377 BTRFS_ROOT_ITEM_KEY);
2378 btrfs_set_disk_key_objectid(&tmp_disk_key, 0);
2379
2380 switch (pass) {
2381 case 0:
2382 btrfs_set_disk_key_objectid(&tmp_disk_key,
2383 BTRFS_ROOT_TREE_OBJECTID);
2384 additional_string = "root ";
2385 next_bytenr = btrfs_super_root(super_hdr);
2386 if (state->print_mask &
2387 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
2388 printk(KERN_INFO "root@%llu\n", next_bytenr);
2389 break;
2390 case 1:
2391 btrfs_set_disk_key_objectid(&tmp_disk_key,
2392 BTRFS_CHUNK_TREE_OBJECTID);
2393 additional_string = "chunk ";
2394 next_bytenr = btrfs_super_chunk_root(super_hdr);
2395 if (state->print_mask &
2396 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
2397 printk(KERN_INFO "chunk@%llu\n", next_bytenr);
2398 break;
2399 case 2:
2400 btrfs_set_disk_key_objectid(&tmp_disk_key,
2401 BTRFS_TREE_LOG_OBJECTID);
2402 additional_string = "log ";
2403 next_bytenr = btrfs_super_log_root(super_hdr);
2404 if (0 == next_bytenr)
2405 continue;
2406 if (state->print_mask &
2407 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
2408 printk(KERN_INFO "log@%llu\n", next_bytenr);
2409 break;
2410 }
2411
2412 num_copies =
2413 btrfs_num_copies(state->root->fs_info,
2414 next_bytenr, BTRFS_SUPER_INFO_SIZE);
2415 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
2416 printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
2417 next_bytenr, num_copies);
2418 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
2419 int was_created;
2420
2421 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2422 printk(KERN_INFO
2423 "btrfsic_process_written_superblock("
2424 "mirror_num=%d)\n", mirror_num);
2425 ret = btrfsic_map_block(state, next_bytenr,
2426 BTRFS_SUPER_INFO_SIZE,
2427 &tmp_next_block_ctx,
2428 mirror_num);
2429 if (ret) {
2430 printk(KERN_INFO
2431 "btrfsic: btrfsic_map_block(@%llu,"
2432 " mirror=%d) failed!\n",
2433 next_bytenr, mirror_num);
2434 return -1;
2435 }
2436
2437 next_block = btrfsic_block_lookup_or_add(
2438 state,
2439 &tmp_next_block_ctx,
2440 additional_string,
2441 1, 0, 1,
2442 mirror_num,
2443 &was_created);
2444 if (NULL == next_block) {
2445 printk(KERN_INFO
2446 "btrfsic: error, kmalloc failed!\n");
2447 btrfsic_release_block_ctx(&tmp_next_block_ctx);
2448 return -1;
2449 }
2450
2451 next_block->disk_key = tmp_disk_key;
2452 if (was_created)
2453 next_block->generation =
2454 BTRFSIC_GENERATION_UNKNOWN;
2455 l = btrfsic_block_link_lookup_or_add(
2456 state,
2457 &tmp_next_block_ctx,
2458 next_block,
2459 superblock,
2460 BTRFSIC_GENERATION_UNKNOWN);
2461 btrfsic_release_block_ctx(&tmp_next_block_ctx);
2462 if (NULL == l)
2463 return -1;
2464 }
2465 }
2466
2467 if (WARN_ON(-1 == btrfsic_check_all_ref_blocks(state, superblock, 0)))
2468 btrfsic_dump_tree(state);
2469
2470 return 0;
2471}
2472
2473static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state,
2474 struct btrfsic_block *const block,
2475 int recursion_level)
2476{
2477 struct list_head *elem_ref_to;
2478 int ret = 0;
2479
2480 if (recursion_level >= 3 + BTRFS_MAX_LEVEL) {
2481 /*
2482 * Note that this situation can happen and does not
2483 * indicate an error in regular cases. It happens
2484 * when disk blocks are freed and later reused.
2485 * The check-integrity module is not aware of any
2486 * block free operations, it just recognizes block
2487 * write operations. Therefore it keeps the linkage
2488 * information for a block until a block is
2489 * rewritten. This can temporarily cause incorrect
2490 * and even circular linkage informations. This
2491 * causes no harm unless such blocks are referenced
2492 * by the most recent super block.
2493 */
2494 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2495 printk(KERN_INFO
2496 "btrfsic: abort cyclic linkage (case 1).\n");
2497
2498 return ret;
2499 }
2500
2501 /*
2502 * This algorithm is recursive because the amount of used stack
2503 * space is very small and the max recursion depth is limited.
2504 */
2505 list_for_each(elem_ref_to, &block->ref_to_list) {
2506 const struct btrfsic_block_link *const l =
2507 list_entry(elem_ref_to, struct btrfsic_block_link,
2508 node_ref_to);
2509
2510 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2511 printk(KERN_INFO
2512 "rl=%d, %c @%llu (%s/%llu/%d)"
2513 " %u* refers to %c @%llu (%s/%llu/%d)\n",
2514 recursion_level,
2515 btrfsic_get_block_type(state, block),
2516 block->logical_bytenr, block->dev_state->name,
2517 block->dev_bytenr, block->mirror_num,
2518 l->ref_cnt,
2519 btrfsic_get_block_type(state, l->block_ref_to),
2520 l->block_ref_to->logical_bytenr,
2521 l->block_ref_to->dev_state->name,
2522 l->block_ref_to->dev_bytenr,
2523 l->block_ref_to->mirror_num);
2524 if (l->block_ref_to->never_written) {
2525 printk(KERN_INFO "btrfs: attempt to write superblock"
2526 " which references block %c @%llu (%s/%llu/%d)"
2527 " which is never written!\n",
2528 btrfsic_get_block_type(state, l->block_ref_to),
2529 l->block_ref_to->logical_bytenr,
2530 l->block_ref_to->dev_state->name,
2531 l->block_ref_to->dev_bytenr,
2532 l->block_ref_to->mirror_num);
2533 ret = -1;
2534 } else if (!l->block_ref_to->is_iodone) {
2535 printk(KERN_INFO "btrfs: attempt to write superblock"
2536 " which references block %c @%llu (%s/%llu/%d)"
2537 " which is not yet iodone!\n",
2538 btrfsic_get_block_type(state, l->block_ref_to),
2539 l->block_ref_to->logical_bytenr,
2540 l->block_ref_to->dev_state->name,
2541 l->block_ref_to->dev_bytenr,
2542 l->block_ref_to->mirror_num);
2543 ret = -1;
2544 } else if (l->block_ref_to->iodone_w_error) {
2545 printk(KERN_INFO "btrfs: attempt to write superblock"
2546 " which references block %c @%llu (%s/%llu/%d)"
2547 " which has write error!\n",
2548 btrfsic_get_block_type(state, l->block_ref_to),
2549 l->block_ref_to->logical_bytenr,
2550 l->block_ref_to->dev_state->name,
2551 l->block_ref_to->dev_bytenr,
2552 l->block_ref_to->mirror_num);
2553 ret = -1;
2554 } else if (l->parent_generation !=
2555 l->block_ref_to->generation &&
2556 BTRFSIC_GENERATION_UNKNOWN !=
2557 l->parent_generation &&
2558 BTRFSIC_GENERATION_UNKNOWN !=
2559 l->block_ref_to->generation) {
2560 printk(KERN_INFO "btrfs: attempt to write superblock"
2561 " which references block %c @%llu (%s/%llu/%d)"
2562 " with generation %llu !="
2563 " parent generation %llu!\n",
2564 btrfsic_get_block_type(state, l->block_ref_to),
2565 l->block_ref_to->logical_bytenr,
2566 l->block_ref_to->dev_state->name,
2567 l->block_ref_to->dev_bytenr,
2568 l->block_ref_to->mirror_num,
2569 l->block_ref_to->generation,
2570 l->parent_generation);
2571 ret = -1;
2572 } else if (l->block_ref_to->flush_gen >
2573 l->block_ref_to->dev_state->last_flush_gen) {
2574 printk(KERN_INFO "btrfs: attempt to write superblock"
2575 " which references block %c @%llu (%s/%llu/%d)"
2576 " which is not flushed out of disk's write cache"
2577 " (block flush_gen=%llu,"
2578 " dev->flush_gen=%llu)!\n",
2579 btrfsic_get_block_type(state, l->block_ref_to),
2580 l->block_ref_to->logical_bytenr,
2581 l->block_ref_to->dev_state->name,
2582 l->block_ref_to->dev_bytenr,
2583 l->block_ref_to->mirror_num, block->flush_gen,
2584 l->block_ref_to->dev_state->last_flush_gen);
2585 ret = -1;
2586 } else if (-1 == btrfsic_check_all_ref_blocks(state,
2587 l->block_ref_to,
2588 recursion_level +
2589 1)) {
2590 ret = -1;
2591 }
2592 }
2593
2594 return ret;
2595}
2596
2597static int btrfsic_is_block_ref_by_superblock(
2598 const struct btrfsic_state *state,
2599 const struct btrfsic_block *block,
2600 int recursion_level)
2601{
2602 struct list_head *elem_ref_from;
2603
2604 if (recursion_level >= 3 + BTRFS_MAX_LEVEL) {
2605 /* refer to comment at "abort cyclic linkage (case 1)" */
2606 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2607 printk(KERN_INFO
2608 "btrfsic: abort cyclic linkage (case 2).\n");
2609
2610 return 0;
2611 }
2612
2613 /*
2614 * This algorithm is recursive because the amount of used stack space
2615 * is very small and the max recursion depth is limited.
2616 */
2617 list_for_each(elem_ref_from, &block->ref_from_list) {
2618 const struct btrfsic_block_link *const l =
2619 list_entry(elem_ref_from, struct btrfsic_block_link,
2620 node_ref_from);
2621
2622 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2623 printk(KERN_INFO
2624 "rl=%d, %c @%llu (%s/%llu/%d)"
2625 " is ref %u* from %c @%llu (%s/%llu/%d)\n",
2626 recursion_level,
2627 btrfsic_get_block_type(state, block),
2628 block->logical_bytenr, block->dev_state->name,
2629 block->dev_bytenr, block->mirror_num,
2630 l->ref_cnt,
2631 btrfsic_get_block_type(state, l->block_ref_from),
2632 l->block_ref_from->logical_bytenr,
2633 l->block_ref_from->dev_state->name,
2634 l->block_ref_from->dev_bytenr,
2635 l->block_ref_from->mirror_num);
2636 if (l->block_ref_from->is_superblock &&
2637 state->latest_superblock->dev_bytenr ==
2638 l->block_ref_from->dev_bytenr &&
2639 state->latest_superblock->dev_state->bdev ==
2640 l->block_ref_from->dev_state->bdev)
2641 return 1;
2642 else if (btrfsic_is_block_ref_by_superblock(state,
2643 l->block_ref_from,
2644 recursion_level +
2645 1))
2646 return 1;
2647 }
2648
2649 return 0;
2650}
2651
2652static void btrfsic_print_add_link(const struct btrfsic_state *state,
2653 const struct btrfsic_block_link *l)
2654{
2655 printk(KERN_INFO
2656 "Add %u* link from %c @%llu (%s/%llu/%d)"
2657 " to %c @%llu (%s/%llu/%d).\n",
2658 l->ref_cnt,
2659 btrfsic_get_block_type(state, l->block_ref_from),
2660 l->block_ref_from->logical_bytenr,
2661 l->block_ref_from->dev_state->name,
2662 l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num,
2663 btrfsic_get_block_type(state, l->block_ref_to),
2664 l->block_ref_to->logical_bytenr,
2665 l->block_ref_to->dev_state->name, l->block_ref_to->dev_bytenr,
2666 l->block_ref_to->mirror_num);
2667}
2668
2669static void btrfsic_print_rem_link(const struct btrfsic_state *state,
2670 const struct btrfsic_block_link *l)
2671{
2672 printk(KERN_INFO
2673 "Rem %u* link from %c @%llu (%s/%llu/%d)"
2674 " to %c @%llu (%s/%llu/%d).\n",
2675 l->ref_cnt,
2676 btrfsic_get_block_type(state, l->block_ref_from),
2677 l->block_ref_from->logical_bytenr,
2678 l->block_ref_from->dev_state->name,
2679 l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num,
2680 btrfsic_get_block_type(state, l->block_ref_to),
2681 l->block_ref_to->logical_bytenr,
2682 l->block_ref_to->dev_state->name, l->block_ref_to->dev_bytenr,
2683 l->block_ref_to->mirror_num);
2684}
2685
2686static char btrfsic_get_block_type(const struct btrfsic_state *state,
2687 const struct btrfsic_block *block)
2688{
2689 if (block->is_superblock &&
2690 state->latest_superblock->dev_bytenr == block->dev_bytenr &&
2691 state->latest_superblock->dev_state->bdev == block->dev_state->bdev)
2692 return 'S';
2693 else if (block->is_superblock)
2694 return 's';
2695 else if (block->is_metadata)
2696 return 'M';
2697 else
2698 return 'D';
2699}
2700
2701static void btrfsic_dump_tree(const struct btrfsic_state *state)
2702{
2703 btrfsic_dump_tree_sub(state, state->latest_superblock, 0);
2704}
2705
2706static void btrfsic_dump_tree_sub(const struct btrfsic_state *state,
2707 const struct btrfsic_block *block,
2708 int indent_level)
2709{
2710 struct list_head *elem_ref_to;
2711 int indent_add;
2712 static char buf[80];
2713 int cursor_position;
2714
2715 /*
2716 * Should better fill an on-stack buffer with a complete line and
2717 * dump it at once when it is time to print a newline character.
2718 */
2719
2720 /*
2721 * This algorithm is recursive because the amount of used stack space
2722 * is very small and the max recursion depth is limited.
2723 */
2724 indent_add = sprintf(buf, "%c-%llu(%s/%llu/%d)",
2725 btrfsic_get_block_type(state, block),
2726 block->logical_bytenr, block->dev_state->name,
2727 block->dev_bytenr, block->mirror_num);
2728 if (indent_level + indent_add > BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) {
2729 printk("[...]\n");
2730 return;
2731 }
2732 printk(buf);
2733 indent_level += indent_add;
2734 if (list_empty(&block->ref_to_list)) {
2735 printk("\n");
2736 return;
2737 }
2738 if (block->mirror_num > 1 &&
2739 !(state->print_mask & BTRFSIC_PRINT_MASK_TREE_WITH_ALL_MIRRORS)) {
2740 printk(" [...]\n");
2741 return;
2742 }
2743
2744 cursor_position = indent_level;
2745 list_for_each(elem_ref_to, &block->ref_to_list) {
2746 const struct btrfsic_block_link *const l =
2747 list_entry(elem_ref_to, struct btrfsic_block_link,
2748 node_ref_to);
2749
2750 while (cursor_position < indent_level) {
2751 printk(" ");
2752 cursor_position++;
2753 }
2754 if (l->ref_cnt > 1)
2755 indent_add = sprintf(buf, " %d*--> ", l->ref_cnt);
2756 else
2757 indent_add = sprintf(buf, " --> ");
2758 if (indent_level + indent_add >
2759 BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) {
2760 printk("[...]\n");
2761 cursor_position = 0;
2762 continue;
2763 }
2764
2765 printk(buf);
2766
2767 btrfsic_dump_tree_sub(state, l->block_ref_to,
2768 indent_level + indent_add);
2769 cursor_position = 0;
2770 }
2771}
2772
2773static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add(
2774 struct btrfsic_state *state,
2775 struct btrfsic_block_data_ctx *next_block_ctx,
2776 struct btrfsic_block *next_block,
2777 struct btrfsic_block *from_block,
2778 u64 parent_generation)
2779{
2780 struct btrfsic_block_link *l;
2781
2782 l = btrfsic_block_link_hashtable_lookup(next_block_ctx->dev->bdev,
2783 next_block_ctx->dev_bytenr,
2784 from_block->dev_state->bdev,
2785 from_block->dev_bytenr,
2786 &state->block_link_hashtable);
2787 if (NULL == l) {
2788 l = btrfsic_block_link_alloc();
2789 if (NULL == l) {
2790 printk(KERN_INFO
2791 "btrfsic: error, kmalloc" " failed!\n");
2792 return NULL;
2793 }
2794
2795 l->block_ref_to = next_block;
2796 l->block_ref_from = from_block;
2797 l->ref_cnt = 1;
2798 l->parent_generation = parent_generation;
2799
2800 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2801 btrfsic_print_add_link(state, l);
2802
2803 list_add(&l->node_ref_to, &from_block->ref_to_list);
2804 list_add(&l->node_ref_from, &next_block->ref_from_list);
2805
2806 btrfsic_block_link_hashtable_add(l,
2807 &state->block_link_hashtable);
2808 } else {
2809 l->ref_cnt++;
2810 l->parent_generation = parent_generation;
2811 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2812 btrfsic_print_add_link(state, l);
2813 }
2814
2815 return l;
2816}
2817
2818static struct btrfsic_block *btrfsic_block_lookup_or_add(
2819 struct btrfsic_state *state,
2820 struct btrfsic_block_data_ctx *block_ctx,
2821 const char *additional_string,
2822 int is_metadata,
2823 int is_iodone,
2824 int never_written,
2825 int mirror_num,
2826 int *was_created)
2827{
2828 struct btrfsic_block *block;
2829
2830 block = btrfsic_block_hashtable_lookup(block_ctx->dev->bdev,
2831 block_ctx->dev_bytenr,
2832 &state->block_hashtable);
2833 if (NULL == block) {
2834 struct btrfsic_dev_state *dev_state;
2835
2836 block = btrfsic_block_alloc();
2837 if (NULL == block) {
2838 printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
2839 return NULL;
2840 }
2841 dev_state = btrfsic_dev_state_lookup(block_ctx->dev->bdev);
2842 if (NULL == dev_state) {
2843 printk(KERN_INFO
2844 "btrfsic: error, lookup dev_state failed!\n");
2845 btrfsic_block_free(block);
2846 return NULL;
2847 }
2848 block->dev_state = dev_state;
2849 block->dev_bytenr = block_ctx->dev_bytenr;
2850 block->logical_bytenr = block_ctx->start;
2851 block->is_metadata = is_metadata;
2852 block->is_iodone = is_iodone;
2853 block->never_written = never_written;
2854 block->mirror_num = mirror_num;
2855 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2856 printk(KERN_INFO
2857 "New %s%c-block @%llu (%s/%llu/%d)\n",
2858 additional_string,
2859 btrfsic_get_block_type(state, block),
2860 block->logical_bytenr, dev_state->name,
2861 block->dev_bytenr, mirror_num);
2862 list_add(&block->all_blocks_node, &state->all_blocks_list);
2863 btrfsic_block_hashtable_add(block, &state->block_hashtable);
2864 if (NULL != was_created)
2865 *was_created = 1;
2866 } else {
2867 if (NULL != was_created)
2868 *was_created = 0;
2869 }
2870
2871 return block;
2872}
2873
2874static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state,
2875 u64 bytenr,
2876 struct btrfsic_dev_state *dev_state,
2877 u64 dev_bytenr)
2878{
2879 int num_copies;
2880 int mirror_num;
2881 int ret;
2882 struct btrfsic_block_data_ctx block_ctx;
2883 int match = 0;
2884
2885 num_copies = btrfs_num_copies(state->root->fs_info,
2886 bytenr, state->metablock_size);
2887
2888 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
2889 ret = btrfsic_map_block(state, bytenr, state->metablock_size,
2890 &block_ctx, mirror_num);
2891 if (ret) {
2892 printk(KERN_INFO "btrfsic:"
2893 " btrfsic_map_block(logical @%llu,"
2894 " mirror %d) failed!\n",
2895 bytenr, mirror_num);
2896 continue;
2897 }
2898
2899 if (dev_state->bdev == block_ctx.dev->bdev &&
2900 dev_bytenr == block_ctx.dev_bytenr) {
2901 match++;
2902 btrfsic_release_block_ctx(&block_ctx);
2903 break;
2904 }
2905 btrfsic_release_block_ctx(&block_ctx);
2906 }
2907
2908 if (WARN_ON(!match)) {
2909 printk(KERN_INFO "btrfs: attempt to write M-block which contains logical bytenr that doesn't map to dev+physical bytenr of submit_bio,"
2910 " buffer->log_bytenr=%llu, submit_bio(bdev=%s,"
2911 " phys_bytenr=%llu)!\n",
2912 bytenr, dev_state->name, dev_bytenr);
2913 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
2914 ret = btrfsic_map_block(state, bytenr,
2915 state->metablock_size,
2916 &block_ctx, mirror_num);
2917 if (ret)
2918 continue;
2919
2920 printk(KERN_INFO "Read logical bytenr @%llu maps to"
2921 " (%s/%llu/%d)\n",
2922 bytenr, block_ctx.dev->name,
2923 block_ctx.dev_bytenr, mirror_num);
2924 }
2925 }
2926}
2927
2928static struct btrfsic_dev_state *btrfsic_dev_state_lookup(
2929 struct block_device *bdev)
2930{
2931 struct btrfsic_dev_state *ds;
2932
2933 ds = btrfsic_dev_state_hashtable_lookup(bdev,
2934 &btrfsic_dev_state_hashtable);
2935 return ds;
2936}
2937
2938int btrfsic_submit_bh(int rw, struct buffer_head *bh)
2939{
2940 struct btrfsic_dev_state *dev_state;
2941
2942 if (!btrfsic_is_initialized)
2943 return submit_bh(rw, bh);
2944
2945 mutex_lock(&btrfsic_mutex);
2946 /* since btrfsic_submit_bh() might also be called before
2947 * btrfsic_mount(), this might return NULL */
2948 dev_state = btrfsic_dev_state_lookup(bh->b_bdev);
2949
2950 /* Only called to write the superblock (incl. FLUSH/FUA) */
2951 if (NULL != dev_state &&
2952 (rw & WRITE) && bh->b_size > 0) {
2953 u64 dev_bytenr;
2954
2955 dev_bytenr = 4096 * bh->b_blocknr;
2956 if (dev_state->state->print_mask &
2957 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
2958 printk(KERN_INFO
2959 "submit_bh(rw=0x%x, blocknr=%llu (bytenr %llu),"
2960 " size=%zu, data=%p, bdev=%p)\n",
2961 rw, (unsigned long long)bh->b_blocknr,
2962 dev_bytenr, bh->b_size, bh->b_data, bh->b_bdev);
2963 btrfsic_process_written_block(dev_state, dev_bytenr,
2964 &bh->b_data, 1, NULL,
2965 NULL, bh, rw);
2966 } else if (NULL != dev_state && (rw & REQ_FLUSH)) {
2967 if (dev_state->state->print_mask &
2968 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
2969 printk(KERN_INFO
2970 "submit_bh(rw=0x%x FLUSH, bdev=%p)\n",
2971 rw, bh->b_bdev);
2972 if (!dev_state->dummy_block_for_bio_bh_flush.is_iodone) {
2973 if ((dev_state->state->print_mask &
2974 (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH |
2975 BTRFSIC_PRINT_MASK_VERBOSE)))
2976 printk(KERN_INFO
2977 "btrfsic_submit_bh(%s) with FLUSH"
2978 " but dummy block already in use"
2979 " (ignored)!\n",
2980 dev_state->name);
2981 } else {
2982 struct btrfsic_block *const block =
2983 &dev_state->dummy_block_for_bio_bh_flush;
2984
2985 block->is_iodone = 0;
2986 block->never_written = 0;
2987 block->iodone_w_error = 0;
2988 block->flush_gen = dev_state->last_flush_gen + 1;
2989 block->submit_bio_bh_rw = rw;
2990 block->orig_bio_bh_private = bh->b_private;
2991 block->orig_bio_bh_end_io.bh = bh->b_end_io;
2992 block->next_in_same_bio = NULL;
2993 bh->b_private = block;
2994 bh->b_end_io = btrfsic_bh_end_io;
2995 }
2996 }
2997 mutex_unlock(&btrfsic_mutex);
2998 return submit_bh(rw, bh);
2999}
3000
3001static void __btrfsic_submit_bio(int rw, struct bio *bio)
3002{
3003 struct btrfsic_dev_state *dev_state;
3004
3005 if (!btrfsic_is_initialized)
3006 return;
3007
3008 mutex_lock(&btrfsic_mutex);
3009 /* since btrfsic_submit_bio() is also called before
3010 * btrfsic_mount(), this might return NULL */
3011 dev_state = btrfsic_dev_state_lookup(bio->bi_bdev);
3012 if (NULL != dev_state &&
3013 (rw & WRITE) && NULL != bio->bi_io_vec) {
3014 unsigned int i;
3015 u64 dev_bytenr;
3016 u64 cur_bytenr;
3017 int bio_is_patched;
3018 char **mapped_datav;
3019
3020 dev_bytenr = 512 * bio->bi_iter.bi_sector;
3021 bio_is_patched = 0;
3022 if (dev_state->state->print_mask &
3023 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
3024 printk(KERN_INFO
3025 "submit_bio(rw=0x%x, bi_vcnt=%u,"
3026 " bi_sector=%llu (bytenr %llu), bi_bdev=%p)\n",
3027 rw, bio->bi_vcnt,
3028 (unsigned long long)bio->bi_iter.bi_sector,
3029 dev_bytenr, bio->bi_bdev);
3030
3031 mapped_datav = kmalloc(sizeof(*mapped_datav) * bio->bi_vcnt,
3032 GFP_NOFS);
3033 if (!mapped_datav)
3034 goto leave;
3035 cur_bytenr = dev_bytenr;
3036 for (i = 0; i < bio->bi_vcnt; i++) {
3037 BUG_ON(bio->bi_io_vec[i].bv_len != PAGE_CACHE_SIZE);
3038 mapped_datav[i] = kmap(bio->bi_io_vec[i].bv_page);
3039 if (!mapped_datav[i]) {
3040 while (i > 0) {
3041 i--;
3042 kunmap(bio->bi_io_vec[i].bv_page);
3043 }
3044 kfree(mapped_datav);
3045 goto leave;
3046 }
3047 if (dev_state->state->print_mask &
3048 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE)
3049 printk(KERN_INFO
3050 "#%u: bytenr=%llu, len=%u, offset=%u\n",
3051 i, cur_bytenr, bio->bi_io_vec[i].bv_len,
3052 bio->bi_io_vec[i].bv_offset);
3053 cur_bytenr += bio->bi_io_vec[i].bv_len;
3054 }
3055 btrfsic_process_written_block(dev_state, dev_bytenr,
3056 mapped_datav, bio->bi_vcnt,
3057 bio, &bio_is_patched,
3058 NULL, rw);
3059 while (i > 0) {
3060 i--;
3061 kunmap(bio->bi_io_vec[i].bv_page);
3062 }
3063 kfree(mapped_datav);
3064 } else if (NULL != dev_state && (rw & REQ_FLUSH)) {
3065 if (dev_state->state->print_mask &
3066 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
3067 printk(KERN_INFO
3068 "submit_bio(rw=0x%x FLUSH, bdev=%p)\n",
3069 rw, bio->bi_bdev);
3070 if (!dev_state->dummy_block_for_bio_bh_flush.is_iodone) {
3071 if ((dev_state->state->print_mask &
3072 (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH |
3073 BTRFSIC_PRINT_MASK_VERBOSE)))
3074 printk(KERN_INFO
3075 "btrfsic_submit_bio(%s) with FLUSH"
3076 " but dummy block already in use"
3077 " (ignored)!\n",
3078 dev_state->name);
3079 } else {
3080 struct btrfsic_block *const block =
3081 &dev_state->dummy_block_for_bio_bh_flush;
3082
3083 block->is_iodone = 0;
3084 block->never_written = 0;
3085 block->iodone_w_error = 0;
3086 block->flush_gen = dev_state->last_flush_gen + 1;
3087 block->submit_bio_bh_rw = rw;
3088 block->orig_bio_bh_private = bio->bi_private;
3089 block->orig_bio_bh_end_io.bio = bio->bi_end_io;
3090 block->next_in_same_bio = NULL;
3091 bio->bi_private = block;
3092 bio->bi_end_io = btrfsic_bio_end_io;
3093 }
3094 }
3095leave:
3096 mutex_unlock(&btrfsic_mutex);
3097}
3098
3099void btrfsic_submit_bio(int rw, struct bio *bio)
3100{
3101 __btrfsic_submit_bio(rw, bio);
3102 submit_bio(rw, bio);
3103}
3104
3105int btrfsic_submit_bio_wait(int rw, struct bio *bio)
3106{
3107 __btrfsic_submit_bio(rw, bio);
3108 return submit_bio_wait(rw, bio);
3109}
3110
3111int btrfsic_mount(struct btrfs_root *root,
3112 struct btrfs_fs_devices *fs_devices,
3113 int including_extent_data, u32 print_mask)
3114{
3115 int ret;
3116 struct btrfsic_state *state;
3117 struct list_head *dev_head = &fs_devices->devices;
3118 struct btrfs_device *device;
3119
3120 if (root->nodesize != root->leafsize) {
3121 printk(KERN_INFO
3122 "btrfsic: cannot handle nodesize %d != leafsize %d!\n",
3123 root->nodesize, root->leafsize);
3124 return -1;
3125 }
3126 if (root->nodesize & ((u64)PAGE_CACHE_SIZE - 1)) {
3127 printk(KERN_INFO
3128 "btrfsic: cannot handle nodesize %d not being a multiple of PAGE_CACHE_SIZE %ld!\n",
3129 root->nodesize, PAGE_CACHE_SIZE);
3130 return -1;
3131 }
3132 if (root->leafsize & ((u64)PAGE_CACHE_SIZE - 1)) {
3133 printk(KERN_INFO
3134 "btrfsic: cannot handle leafsize %d not being a multiple of PAGE_CACHE_SIZE %ld!\n",
3135 root->leafsize, PAGE_CACHE_SIZE);
3136 return -1;
3137 }
3138 if (root->sectorsize & ((u64)PAGE_CACHE_SIZE - 1)) {
3139 printk(KERN_INFO
3140 "btrfsic: cannot handle sectorsize %d not being a multiple of PAGE_CACHE_SIZE %ld!\n",
3141 root->sectorsize, PAGE_CACHE_SIZE);
3142 return -1;
3143 }
3144 state = kzalloc(sizeof(*state), GFP_NOFS);
3145 if (NULL == state) {
3146 printk(KERN_INFO "btrfs check-integrity: kmalloc() failed!\n");
3147 return -1;
3148 }
3149
3150 if (!btrfsic_is_initialized) {
3151 mutex_init(&btrfsic_mutex);
3152 btrfsic_dev_state_hashtable_init(&btrfsic_dev_state_hashtable);
3153 btrfsic_is_initialized = 1;
3154 }
3155 mutex_lock(&btrfsic_mutex);
3156 state->root = root;
3157 state->print_mask = print_mask;
3158 state->include_extent_data = including_extent_data;
3159 state->csum_size = 0;
3160 state->metablock_size = root->nodesize;
3161 state->datablock_size = root->sectorsize;
3162 INIT_LIST_HEAD(&state->all_blocks_list);
3163 btrfsic_block_hashtable_init(&state->block_hashtable);
3164 btrfsic_block_link_hashtable_init(&state->block_link_hashtable);
3165 state->max_superblock_generation = 0;
3166 state->latest_superblock = NULL;
3167
3168 list_for_each_entry(device, dev_head, dev_list) {
3169 struct btrfsic_dev_state *ds;
3170 char *p;
3171
3172 if (!device->bdev || !device->name)
3173 continue;
3174
3175 ds = btrfsic_dev_state_alloc();
3176 if (NULL == ds) {
3177 printk(KERN_INFO
3178 "btrfs check-integrity: kmalloc() failed!\n");
3179 mutex_unlock(&btrfsic_mutex);
3180 return -1;
3181 }
3182 ds->bdev = device->bdev;
3183 ds->state = state;
3184 bdevname(ds->bdev, ds->name);
3185 ds->name[BDEVNAME_SIZE - 1] = '\0';
3186 for (p = ds->name; *p != '\0'; p++);
3187 while (p > ds->name && *p != '/')
3188 p--;
3189 if (*p == '/')
3190 p++;
3191 strlcpy(ds->name, p, sizeof(ds->name));
3192 btrfsic_dev_state_hashtable_add(ds,
3193 &btrfsic_dev_state_hashtable);
3194 }
3195
3196 ret = btrfsic_process_superblock(state, fs_devices);
3197 if (0 != ret) {
3198 mutex_unlock(&btrfsic_mutex);
3199 btrfsic_unmount(root, fs_devices);
3200 return ret;
3201 }
3202
3203 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_DATABASE)
3204 btrfsic_dump_database(state);
3205 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_TREE)
3206 btrfsic_dump_tree(state);
3207
3208 mutex_unlock(&btrfsic_mutex);
3209 return 0;
3210}
3211
3212void btrfsic_unmount(struct btrfs_root *root,
3213 struct btrfs_fs_devices *fs_devices)
3214{
3215 struct list_head *elem_all;
3216 struct list_head *tmp_all;
3217 struct btrfsic_state *state;
3218 struct list_head *dev_head = &fs_devices->devices;
3219 struct btrfs_device *device;
3220
3221 if (!btrfsic_is_initialized)
3222 return;
3223
3224 mutex_lock(&btrfsic_mutex);
3225
3226 state = NULL;
3227 list_for_each_entry(device, dev_head, dev_list) {
3228 struct btrfsic_dev_state *ds;
3229
3230 if (!device->bdev || !device->name)
3231 continue;
3232
3233 ds = btrfsic_dev_state_hashtable_lookup(
3234 device->bdev,
3235 &btrfsic_dev_state_hashtable);
3236 if (NULL != ds) {
3237 state = ds->state;
3238 btrfsic_dev_state_hashtable_remove(ds);
3239 btrfsic_dev_state_free(ds);
3240 }
3241 }
3242
3243 if (NULL == state) {
3244 printk(KERN_INFO
3245 "btrfsic: error, cannot find state information"
3246 " on umount!\n");
3247 mutex_unlock(&btrfsic_mutex);
3248 return;
3249 }
3250
3251 /*
3252 * Don't care about keeping the lists' state up to date,
3253 * just free all memory that was allocated dynamically.
3254 * Free the blocks and the block_links.
3255 */
3256 list_for_each_safe(elem_all, tmp_all, &state->all_blocks_list) {
3257 struct btrfsic_block *const b_all =
3258 list_entry(elem_all, struct btrfsic_block,
3259 all_blocks_node);
3260 struct list_head *elem_ref_to;
3261 struct list_head *tmp_ref_to;
3262
3263 list_for_each_safe(elem_ref_to, tmp_ref_to,
3264 &b_all->ref_to_list) {
3265 struct btrfsic_block_link *const l =
3266 list_entry(elem_ref_to,
3267 struct btrfsic_block_link,
3268 node_ref_to);
3269
3270 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
3271 btrfsic_print_rem_link(state, l);
3272
3273 l->ref_cnt--;
3274 if (0 == l->ref_cnt)
3275 btrfsic_block_link_free(l);
3276 }
3277
3278 if (b_all->is_iodone || b_all->never_written)
3279 btrfsic_block_free(b_all);
3280 else
3281 printk(KERN_INFO "btrfs: attempt to free %c-block"
3282 " @%llu (%s/%llu/%d) on umount which is"
3283 " not yet iodone!\n",
3284 btrfsic_get_block_type(state, b_all),
3285 b_all->logical_bytenr, b_all->dev_state->name,
3286 b_all->dev_bytenr, b_all->mirror_num);
3287 }
3288
3289 mutex_unlock(&btrfsic_mutex);
3290
3291 kfree(state);
3292}