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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm...
[linux-2.6.git] / fs / btrfs / check-integrity.c
blobb50764bef1410c2750b17d943ae3597899b3ee9e
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/crc32c.h>
96 #include <linux/genhd.h>
97 #include <linux/blkdev.h>
98 #include "ctree.h"
99 #include "disk-io.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
138 struct btrfsic_dev_state;
139 struct btrfsic_state;
140
141 struct 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 */
185 struct 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
196 struct 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
206 struct btrfsic_block_hashtable {
207 struct list_head table[BTRFSIC_BLOCK_HASHTABLE_SIZE];
208 };
209
210 struct btrfsic_block_link_hashtable {
211 struct list_head table[BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE];
212 };
213
214 struct btrfsic_dev_state_hashtable {
215 struct list_head table[BTRFSIC_DEV2STATE_HASHTABLE_SIZE];
216 };
217
218 struct 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() */
230 struct 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 */
247 struct 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
261 static void btrfsic_block_init(struct btrfsic_block *b);
262 static struct btrfsic_block *btrfsic_block_alloc(void);
263 static void btrfsic_block_free(struct btrfsic_block *b);
264 static void btrfsic_block_link_init(struct btrfsic_block_link *n);
265 static struct btrfsic_block_link *btrfsic_block_link_alloc(void);
266 static void btrfsic_block_link_free(struct btrfsic_block_link *n);
267 static void btrfsic_dev_state_init(struct btrfsic_dev_state *ds);
268 static struct btrfsic_dev_state *btrfsic_dev_state_alloc(void);
269 static void btrfsic_dev_state_free(struct btrfsic_dev_state *ds);
270 static void btrfsic_block_hashtable_init(struct btrfsic_block_hashtable *h);
271 static void btrfsic_block_hashtable_add(struct btrfsic_block *b,
272 struct btrfsic_block_hashtable *h);
273 static void btrfsic_block_hashtable_remove(struct btrfsic_block *b);
274 static struct btrfsic_block *btrfsic_block_hashtable_lookup(
275 struct block_device *bdev,
276 u64 dev_bytenr,
277 struct btrfsic_block_hashtable *h);
278 static void btrfsic_block_link_hashtable_init(
279 struct btrfsic_block_link_hashtable *h);
280 static void btrfsic_block_link_hashtable_add(
281 struct btrfsic_block_link *l,
282 struct btrfsic_block_link_hashtable *h);
283 static void btrfsic_block_link_hashtable_remove(struct btrfsic_block_link *l);
284 static 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);
290 static void btrfsic_dev_state_hashtable_init(
291 struct btrfsic_dev_state_hashtable *h);
292 static void btrfsic_dev_state_hashtable_add(
293 struct btrfsic_dev_state *ds,
294 struct btrfsic_dev_state_hashtable *h);
295 static void btrfsic_dev_state_hashtable_remove(struct btrfsic_dev_state *ds);
296 static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(
297 struct block_device *bdev,
298 struct btrfsic_dev_state_hashtable *h);
299 static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void);
300 static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf);
301 static int btrfsic_process_superblock(struct btrfsic_state *state,
302 struct btrfs_fs_devices *fs_devices);
303 static 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);
307 static void btrfsic_read_from_block_data(
308 struct btrfsic_block_data_ctx *block_ctx,
309 void *dst, u32 offset, size_t len);
310 static 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);
322 static 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);
326 static 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);
329 static 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);
332 static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx);
333 static int btrfsic_read_block(struct btrfsic_state *state,
334 struct btrfsic_block_data_ctx *block_ctx);
335 static void btrfsic_dump_database(struct btrfsic_state *state);
336 static void btrfsic_complete_bio_end_io(struct bio *bio, int err);
337 static int btrfsic_test_for_metadata(struct btrfsic_state *state,
338 char **datav, unsigned int num_pages);
339 static void btrfsic_process_written_block(struct btrfsic_dev_state *dev_state,
340 u64 dev_bytenr, char **mapped_datav,
341 unsigned int num_pages,
342 struct bio *bio, int *bio_is_patched,
343 struct buffer_head *bh,
344 int submit_bio_bh_rw);
345 static int btrfsic_process_written_superblock(
346 struct btrfsic_state *state,
347 struct btrfsic_block *const block,
348 struct btrfs_super_block *const super_hdr);
349 static void btrfsic_bio_end_io(struct bio *bp, int bio_error_status);
350 static void btrfsic_bh_end_io(struct buffer_head *bh, int uptodate);
351 static int btrfsic_is_block_ref_by_superblock(const struct btrfsic_state *state,
352 const struct btrfsic_block *block,
353 int recursion_level);
354 static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state,
355 struct btrfsic_block *const block,
356 int recursion_level);
357 static void btrfsic_print_add_link(const struct btrfsic_state *state,
358 const struct btrfsic_block_link *l);
359 static void btrfsic_print_rem_link(const struct btrfsic_state *state,
360 const struct btrfsic_block_link *l);
361 static char btrfsic_get_block_type(const struct btrfsic_state *state,
362 const struct btrfsic_block *block);
363 static void btrfsic_dump_tree(const struct btrfsic_state *state);
364 static void btrfsic_dump_tree_sub(const struct btrfsic_state *state,
365 const struct btrfsic_block *block,
366 int indent_level);
367 static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add(
368 struct btrfsic_state *state,
369 struct btrfsic_block_data_ctx *next_block_ctx,
370 struct btrfsic_block *next_block,
371 struct btrfsic_block *from_block,
372 u64 parent_generation);
373 static struct btrfsic_block *btrfsic_block_lookup_or_add(
374 struct btrfsic_state *state,
375 struct btrfsic_block_data_ctx *block_ctx,
376 const char *additional_string,
377 int is_metadata,
378 int is_iodone,
379 int never_written,
380 int mirror_num,
381 int *was_created);
382 static int btrfsic_process_superblock_dev_mirror(
383 struct btrfsic_state *state,
384 struct btrfsic_dev_state *dev_state,
385 struct btrfs_device *device,
386 int superblock_mirror_num,
387 struct btrfsic_dev_state **selected_dev_state,
388 struct btrfs_super_block *selected_super);
389 static struct btrfsic_dev_state *btrfsic_dev_state_lookup(
390 struct block_device *bdev);
391 static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state,
392 u64 bytenr,
393 struct btrfsic_dev_state *dev_state,
394 u64 dev_bytenr);
395
396 static struct mutex btrfsic_mutex;
397 static int btrfsic_is_initialized;
398 static struct btrfsic_dev_state_hashtable btrfsic_dev_state_hashtable;
399
400
401 static void btrfsic_block_init(struct btrfsic_block *b)
402 {
403 b->magic_num = BTRFSIC_BLOCK_MAGIC_NUMBER;
404 b->dev_state = NULL;
405 b->dev_bytenr = 0;
406 b->logical_bytenr = 0;
407 b->generation = BTRFSIC_GENERATION_UNKNOWN;
408 b->disk_key.objectid = 0;
409 b->disk_key.type = 0;
410 b->disk_key.offset = 0;
411 b->is_metadata = 0;
412 b->is_superblock = 0;
413 b->is_iodone = 0;
414 b->iodone_w_error = 0;
415 b->never_written = 0;
416 b->mirror_num = 0;
417 b->next_in_same_bio = NULL;
418 b->orig_bio_bh_private = NULL;
419 b->orig_bio_bh_end_io.bio = NULL;
420 INIT_LIST_HEAD(&b->collision_resolving_node);
421 INIT_LIST_HEAD(&b->all_blocks_node);
422 INIT_LIST_HEAD(&b->ref_to_list);
423 INIT_LIST_HEAD(&b->ref_from_list);
424 b->submit_bio_bh_rw = 0;
425 b->flush_gen = 0;
426 }
427
428 static struct btrfsic_block *btrfsic_block_alloc(void)
429 {
430 struct btrfsic_block *b;
431
432 b = kzalloc(sizeof(*b), GFP_NOFS);
433 if (NULL != b)
434 btrfsic_block_init(b);
435
436 return b;
437 }
438
439 static void btrfsic_block_free(struct btrfsic_block *b)
440 {
441 BUG_ON(!(NULL == b || BTRFSIC_BLOCK_MAGIC_NUMBER == b->magic_num));
442 kfree(b);
443 }
444
445 static void btrfsic_block_link_init(struct btrfsic_block_link *l)
446 {
447 l->magic_num = BTRFSIC_BLOCK_LINK_MAGIC_NUMBER;
448 l->ref_cnt = 1;
449 INIT_LIST_HEAD(&l->node_ref_to);
450 INIT_LIST_HEAD(&l->node_ref_from);
451 INIT_LIST_HEAD(&l->collision_resolving_node);
452 l->block_ref_to = NULL;
453 l->block_ref_from = NULL;
454 }
455
456 static struct btrfsic_block_link *btrfsic_block_link_alloc(void)
457 {
458 struct btrfsic_block_link *l;
459
460 l = kzalloc(sizeof(*l), GFP_NOFS);
461 if (NULL != l)
462 btrfsic_block_link_init(l);
463
464 return l;
465 }
466
467 static void btrfsic_block_link_free(struct btrfsic_block_link *l)
468 {
469 BUG_ON(!(NULL == l || BTRFSIC_BLOCK_LINK_MAGIC_NUMBER == l->magic_num));
470 kfree(l);
471 }
472
473 static void btrfsic_dev_state_init(struct btrfsic_dev_state *ds)
474 {
475 ds->magic_num = BTRFSIC_DEV2STATE_MAGIC_NUMBER;
476 ds->bdev = NULL;
477 ds->state = NULL;
478 ds->name[0] = '\0';
479 INIT_LIST_HEAD(&ds->collision_resolving_node);
480 ds->last_flush_gen = 0;
481 btrfsic_block_init(&ds->dummy_block_for_bio_bh_flush);
482 ds->dummy_block_for_bio_bh_flush.is_iodone = 1;
483 ds->dummy_block_for_bio_bh_flush.dev_state = ds;
484 }
485
486 static struct btrfsic_dev_state *btrfsic_dev_state_alloc(void)
487 {
488 struct btrfsic_dev_state *ds;
489
490 ds = kzalloc(sizeof(*ds), GFP_NOFS);
491 if (NULL != ds)
492 btrfsic_dev_state_init(ds);
493
494 return ds;
495 }
496
497 static void btrfsic_dev_state_free(struct btrfsic_dev_state *ds)
498 {
499 BUG_ON(!(NULL == ds ||
500 BTRFSIC_DEV2STATE_MAGIC_NUMBER == ds->magic_num));
501 kfree(ds);
502 }
503
504 static void btrfsic_block_hashtable_init(struct btrfsic_block_hashtable *h)
505 {
506 int i;
507
508 for (i = 0; i < BTRFSIC_BLOCK_HASHTABLE_SIZE; i++)
509 INIT_LIST_HEAD(h->table + i);
510 }
511
512 static void btrfsic_block_hashtable_add(struct btrfsic_block *b,
513 struct btrfsic_block_hashtable *h)
514 {
515 const unsigned int hashval =
516 (((unsigned int)(b->dev_bytenr >> 16)) ^
517 ((unsigned int)((uintptr_t)b->dev_state->bdev))) &
518 (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1);
519
520 list_add(&b->collision_resolving_node, h->table + hashval);
521 }
522
523 static void btrfsic_block_hashtable_remove(struct btrfsic_block *b)
524 {
525 list_del(&b->collision_resolving_node);
526 }
527
528 static struct btrfsic_block *btrfsic_block_hashtable_lookup(
529 struct block_device *bdev,
530 u64 dev_bytenr,
531 struct btrfsic_block_hashtable *h)
532 {
533 const unsigned int hashval =
534 (((unsigned int)(dev_bytenr >> 16)) ^
535 ((unsigned int)((uintptr_t)bdev))) &
536 (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1);
537 struct list_head *elem;
538
539 list_for_each(elem, h->table + hashval) {
540 struct btrfsic_block *const b =
541 list_entry(elem, struct btrfsic_block,
542 collision_resolving_node);
543
544 if (b->dev_state->bdev == bdev && b->dev_bytenr == dev_bytenr)
545 return b;
546 }
547
548 return NULL;
549 }
550
551 static void btrfsic_block_link_hashtable_init(
552 struct btrfsic_block_link_hashtable *h)
553 {
554 int i;
555
556 for (i = 0; i < BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE; i++)
557 INIT_LIST_HEAD(h->table + i);
558 }
559
560 static void btrfsic_block_link_hashtable_add(
561 struct btrfsic_block_link *l,
562 struct btrfsic_block_link_hashtable *h)
563 {
564 const unsigned int hashval =
565 (((unsigned int)(l->block_ref_to->dev_bytenr >> 16)) ^
566 ((unsigned int)(l->block_ref_from->dev_bytenr >> 16)) ^
567 ((unsigned int)((uintptr_t)l->block_ref_to->dev_state->bdev)) ^
568 ((unsigned int)((uintptr_t)l->block_ref_from->dev_state->bdev)))
569 & (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1);
570
571 BUG_ON(NULL == l->block_ref_to);
572 BUG_ON(NULL == l->block_ref_from);
573 list_add(&l->collision_resolving_node, h->table + hashval);
574 }
575
576 static void btrfsic_block_link_hashtable_remove(struct btrfsic_block_link *l)
577 {
578 list_del(&l->collision_resolving_node);
579 }
580
581 static struct btrfsic_block_link *btrfsic_block_link_hashtable_lookup(
582 struct block_device *bdev_ref_to,
583 u64 dev_bytenr_ref_to,
584 struct block_device *bdev_ref_from,
585 u64 dev_bytenr_ref_from,
586 struct btrfsic_block_link_hashtable *h)
587 {
588 const unsigned int hashval =
589 (((unsigned int)(dev_bytenr_ref_to >> 16)) ^
590 ((unsigned int)(dev_bytenr_ref_from >> 16)) ^
591 ((unsigned int)((uintptr_t)bdev_ref_to)) ^
592 ((unsigned int)((uintptr_t)bdev_ref_from))) &
593 (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1);
594 struct list_head *elem;
595
596 list_for_each(elem, h->table + hashval) {
597 struct btrfsic_block_link *const l =
598 list_entry(elem, struct btrfsic_block_link,
599 collision_resolving_node);
600
601 BUG_ON(NULL == l->block_ref_to);
602 BUG_ON(NULL == l->block_ref_from);
603 if (l->block_ref_to->dev_state->bdev == bdev_ref_to &&
604 l->block_ref_to->dev_bytenr == dev_bytenr_ref_to &&
605 l->block_ref_from->dev_state->bdev == bdev_ref_from &&
606 l->block_ref_from->dev_bytenr == dev_bytenr_ref_from)
607 return l;
608 }
609
610 return NULL;
611 }
612
613 static void btrfsic_dev_state_hashtable_init(
614 struct btrfsic_dev_state_hashtable *h)
615 {
616 int i;
617
618 for (i = 0; i < BTRFSIC_DEV2STATE_HASHTABLE_SIZE; i++)
619 INIT_LIST_HEAD(h->table + i);
620 }
621
622 static void btrfsic_dev_state_hashtable_add(
623 struct btrfsic_dev_state *ds,
624 struct btrfsic_dev_state_hashtable *h)
625 {
626 const unsigned int hashval =
627 (((unsigned int)((uintptr_t)ds->bdev)) &
628 (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1));
629
630 list_add(&ds->collision_resolving_node, h->table + hashval);
631 }
632
633 static void btrfsic_dev_state_hashtable_remove(struct btrfsic_dev_state *ds)
634 {
635 list_del(&ds->collision_resolving_node);
636 }
637
638 static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(
639 struct block_device *bdev,
640 struct btrfsic_dev_state_hashtable *h)
641 {
642 const unsigned int hashval =
643 (((unsigned int)((uintptr_t)bdev)) &
644 (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1));
645 struct list_head *elem;
646
647 list_for_each(elem, h->table + hashval) {
648 struct btrfsic_dev_state *const ds =
649 list_entry(elem, struct btrfsic_dev_state,
650 collision_resolving_node);
651
652 if (ds->bdev == bdev)
653 return ds;
654 }
655
656 return NULL;
657 }
658
659 static int btrfsic_process_superblock(struct btrfsic_state *state,
660 struct btrfs_fs_devices *fs_devices)
661 {
662 int ret = 0;
663 struct btrfs_super_block *selected_super;
664 struct list_head *dev_head = &fs_devices->devices;
665 struct btrfs_device *device;
666 struct btrfsic_dev_state *selected_dev_state = NULL;
667 int pass;
668
669 BUG_ON(NULL == state);
670 selected_super = kzalloc(sizeof(*selected_super), GFP_NOFS);
671 if (NULL == selected_super) {
672 printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
673 return -1;
674 }
675
676 list_for_each_entry(device, dev_head, dev_list) {
677 int i;
678 struct btrfsic_dev_state *dev_state;
679
680 if (!device->bdev || !device->name)
681 continue;
682
683 dev_state = btrfsic_dev_state_lookup(device->bdev);
684 BUG_ON(NULL == dev_state);
685 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
686 ret = btrfsic_process_superblock_dev_mirror(
687 state, dev_state, device, i,
688 &selected_dev_state, selected_super);
689 if (0 != ret && 0 == i) {
690 kfree(selected_super);
691 return ret;
692 }
693 }
694 }
695
696 if (NULL == state->latest_superblock) {
697 printk(KERN_INFO "btrfsic: no superblock found!\n");
698 kfree(selected_super);
699 return -1;
700 }
701
702 state->csum_size = btrfs_super_csum_size(selected_super);
703
704 for (pass = 0; pass < 3; pass++) {
705 int num_copies;
706 int mirror_num;
707 u64 next_bytenr;
708
709 switch (pass) {
710 case 0:
711 next_bytenr = btrfs_super_root(selected_super);
712 if (state->print_mask &
713 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
714 printk(KERN_INFO "root@%llu\n", next_bytenr);
715 break;
716 case 1:
717 next_bytenr = btrfs_super_chunk_root(selected_super);
718 if (state->print_mask &
719 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
720 printk(KERN_INFO "chunk@%llu\n", next_bytenr);
721 break;
722 case 2:
723 next_bytenr = btrfs_super_log_root(selected_super);
724 if (0 == next_bytenr)
725 continue;
726 if (state->print_mask &
727 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
728 printk(KERN_INFO "log@%llu\n", next_bytenr);
729 break;
730 }
731
732 num_copies =
733 btrfs_num_copies(state->root->fs_info,
734 next_bytenr, state->metablock_size);
735 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
736 printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
737 next_bytenr, num_copies);
738
739 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
740 struct btrfsic_block *next_block;
741 struct btrfsic_block_data_ctx tmp_next_block_ctx;
742 struct btrfsic_block_link *l;
743
744 ret = btrfsic_map_block(state, next_bytenr,
745 state->metablock_size,
746 &tmp_next_block_ctx,
747 mirror_num);
748 if (ret) {
749 printk(KERN_INFO "btrfsic:"
750 " btrfsic_map_block(root @%llu,"
751 " mirror %d) failed!\n",
752 next_bytenr, mirror_num);
753 kfree(selected_super);
754 return -1;
755 }
756
757 next_block = btrfsic_block_hashtable_lookup(
758 tmp_next_block_ctx.dev->bdev,
759 tmp_next_block_ctx.dev_bytenr,
760 &state->block_hashtable);
761 BUG_ON(NULL == next_block);
762
763 l = btrfsic_block_link_hashtable_lookup(
764 tmp_next_block_ctx.dev->bdev,
765 tmp_next_block_ctx.dev_bytenr,
766 state->latest_superblock->dev_state->
767 bdev,
768 state->latest_superblock->dev_bytenr,
769 &state->block_link_hashtable);
770 BUG_ON(NULL == l);
771
772 ret = btrfsic_read_block(state, &tmp_next_block_ctx);
773 if (ret < (int)PAGE_CACHE_SIZE) {
774 printk(KERN_INFO
775 "btrfsic: read @logical %llu failed!\n",
776 tmp_next_block_ctx.start);
777 btrfsic_release_block_ctx(&tmp_next_block_ctx);
778 kfree(selected_super);
779 return -1;
780 }
781
782 ret = btrfsic_process_metablock(state,
783 next_block,
784 &tmp_next_block_ctx,
785 BTRFS_MAX_LEVEL + 3, 1);
786 btrfsic_release_block_ctx(&tmp_next_block_ctx);
787 }
788 }
789
790 kfree(selected_super);
791 return ret;
792 }
793
794 static int btrfsic_process_superblock_dev_mirror(
795 struct btrfsic_state *state,
796 struct btrfsic_dev_state *dev_state,
797 struct btrfs_device *device,
798 int superblock_mirror_num,
799 struct btrfsic_dev_state **selected_dev_state,
800 struct btrfs_super_block *selected_super)
801 {
802 struct btrfs_super_block *super_tmp;
803 u64 dev_bytenr;
804 struct buffer_head *bh;
805 struct btrfsic_block *superblock_tmp;
806 int pass;
807 struct block_device *const superblock_bdev = device->bdev;
808
809 /* super block bytenr is always the unmapped device bytenr */
810 dev_bytenr = btrfs_sb_offset(superblock_mirror_num);
811 if (dev_bytenr + BTRFS_SUPER_INFO_SIZE > device->total_bytes)
812 return -1;
813 bh = __bread(superblock_bdev, dev_bytenr / 4096,
814 BTRFS_SUPER_INFO_SIZE);
815 if (NULL == bh)
816 return -1;
817 super_tmp = (struct btrfs_super_block *)
818 (bh->b_data + (dev_bytenr & 4095));
819
820 if (btrfs_super_bytenr(super_tmp) != dev_bytenr ||
821 btrfs_super_magic(super_tmp) != BTRFS_MAGIC ||
822 memcmp(device->uuid, super_tmp->dev_item.uuid, BTRFS_UUID_SIZE) ||
823 btrfs_super_nodesize(super_tmp) != state->metablock_size ||
824 btrfs_super_leafsize(super_tmp) != state->metablock_size ||
825 btrfs_super_sectorsize(super_tmp) != state->datablock_size) {
826 brelse(bh);
827 return 0;
828 }
829
830 superblock_tmp =
831 btrfsic_block_hashtable_lookup(superblock_bdev,
832 dev_bytenr,
833 &state->block_hashtable);
834 if (NULL == superblock_tmp) {
835 superblock_tmp = btrfsic_block_alloc();
836 if (NULL == superblock_tmp) {
837 printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
838 brelse(bh);
839 return -1;
840 }
841 /* for superblock, only the dev_bytenr makes sense */
842 superblock_tmp->dev_bytenr = dev_bytenr;
843 superblock_tmp->dev_state = dev_state;
844 superblock_tmp->logical_bytenr = dev_bytenr;
845 superblock_tmp->generation = btrfs_super_generation(super_tmp);
846 superblock_tmp->is_metadata = 1;
847 superblock_tmp->is_superblock = 1;
848 superblock_tmp->is_iodone = 1;
849 superblock_tmp->never_written = 0;
850 superblock_tmp->mirror_num = 1 + superblock_mirror_num;
851 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
852 printk_in_rcu(KERN_INFO "New initial S-block (bdev %p, %s)"
853 " @%llu (%s/%llu/%d)\n",
854 superblock_bdev,
855 rcu_str_deref(device->name), dev_bytenr,
856 dev_state->name, dev_bytenr,
857 superblock_mirror_num);
858 list_add(&superblock_tmp->all_blocks_node,
859 &state->all_blocks_list);
860 btrfsic_block_hashtable_add(superblock_tmp,
861 &state->block_hashtable);
862 }
863
864 /* select the one with the highest generation field */
865 if (btrfs_super_generation(super_tmp) >
866 state->max_superblock_generation ||
867 0 == state->max_superblock_generation) {
868 memcpy(selected_super, super_tmp, sizeof(*selected_super));
869 *selected_dev_state = dev_state;
870 state->max_superblock_generation =
871 btrfs_super_generation(super_tmp);
872 state->latest_superblock = superblock_tmp;
873 }
874
875 for (pass = 0; pass < 3; pass++) {
876 u64 next_bytenr;
877 int num_copies;
878 int mirror_num;
879 const char *additional_string = NULL;
880 struct btrfs_disk_key tmp_disk_key;
881
882 tmp_disk_key.type = BTRFS_ROOT_ITEM_KEY;
883 tmp_disk_key.offset = 0;
884 switch (pass) {
885 case 0:
886 btrfs_set_disk_key_objectid(&tmp_disk_key,
887 BTRFS_ROOT_TREE_OBJECTID);
888 additional_string = "initial root ";
889 next_bytenr = btrfs_super_root(super_tmp);
890 break;
891 case 1:
892 btrfs_set_disk_key_objectid(&tmp_disk_key,
893 BTRFS_CHUNK_TREE_OBJECTID);
894 additional_string = "initial chunk ";
895 next_bytenr = btrfs_super_chunk_root(super_tmp);
896 break;
897 case 2:
898 btrfs_set_disk_key_objectid(&tmp_disk_key,
899 BTRFS_TREE_LOG_OBJECTID);
900 additional_string = "initial log ";
901 next_bytenr = btrfs_super_log_root(super_tmp);
902 if (0 == next_bytenr)
903 continue;
904 break;
905 }
906
907 num_copies =
908 btrfs_num_copies(state->root->fs_info,
909 next_bytenr, state->metablock_size);
910 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
911 printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
912 next_bytenr, num_copies);
913 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
914 struct btrfsic_block *next_block;
915 struct btrfsic_block_data_ctx tmp_next_block_ctx;
916 struct btrfsic_block_link *l;
917
918 if (btrfsic_map_block(state, next_bytenr,
919 state->metablock_size,
920 &tmp_next_block_ctx,
921 mirror_num)) {
922 printk(KERN_INFO "btrfsic: btrfsic_map_block("
923 "bytenr @%llu, mirror %d) failed!\n",
924 next_bytenr, mirror_num);
925 brelse(bh);
926 return -1;
927 }
928
929 next_block = btrfsic_block_lookup_or_add(
930 state, &tmp_next_block_ctx,
931 additional_string, 1, 1, 0,
932 mirror_num, NULL);
933 if (NULL == next_block) {
934 btrfsic_release_block_ctx(&tmp_next_block_ctx);
935 brelse(bh);
936 return -1;
937 }
938
939 next_block->disk_key = tmp_disk_key;
940 next_block->generation = BTRFSIC_GENERATION_UNKNOWN;
941 l = btrfsic_block_link_lookup_or_add(
942 state, &tmp_next_block_ctx,
943 next_block, superblock_tmp,
944 BTRFSIC_GENERATION_UNKNOWN);
945 btrfsic_release_block_ctx(&tmp_next_block_ctx);
946 if (NULL == l) {
947 brelse(bh);
948 return -1;
949 }
950 }
951 }
952 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_ALL_TREES)
953 btrfsic_dump_tree_sub(state, superblock_tmp, 0);
954
955 brelse(bh);
956 return 0;
957 }
958
959 static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void)
960 {
961 struct btrfsic_stack_frame *sf;
962
963 sf = kzalloc(sizeof(*sf), GFP_NOFS);
964 if (NULL == sf)
965 printk(KERN_INFO "btrfsic: alloc memory failed!\n");
966 else
967 sf->magic = BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER;
968 return sf;
969 }
970
971 static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf)
972 {
973 BUG_ON(!(NULL == sf ||
974 BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER == sf->magic));
975 kfree(sf);
976 }
977
978 static int btrfsic_process_metablock(
979 struct btrfsic_state *state,
980 struct btrfsic_block *const first_block,
981 struct btrfsic_block_data_ctx *const first_block_ctx,
982 int first_limit_nesting, int force_iodone_flag)
983 {
984 struct btrfsic_stack_frame initial_stack_frame = { 0 };
985 struct btrfsic_stack_frame *sf;
986 struct btrfsic_stack_frame *next_stack;
987 struct btrfs_header *const first_hdr =
988 (struct btrfs_header *)first_block_ctx->datav[0];
989
990 BUG_ON(!first_hdr);
991 sf = &initial_stack_frame;
992 sf->error = 0;
993 sf->i = -1;
994 sf->limit_nesting = first_limit_nesting;
995 sf->block = first_block;
996 sf->block_ctx = first_block_ctx;
997 sf->next_block = NULL;
998 sf->hdr = first_hdr;
999 sf->prev = NULL;
1000
1001 continue_with_new_stack_frame:
1002 sf->block->generation = le64_to_cpu(sf->hdr->generation);
1003 if (0 == sf->hdr->level) {
1004 struct btrfs_leaf *const leafhdr =
1005 (struct btrfs_leaf *)sf->hdr;
1006
1007 if (-1 == sf->i) {
1008 sf->nr = btrfs_stack_header_nritems(&leafhdr->header);
1009
1010 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1011 printk(KERN_INFO
1012 "leaf %llu items %d generation %llu"
1013 " owner %llu\n",
1014 sf->block_ctx->start, sf->nr,
1015 btrfs_stack_header_generation(
1016 &leafhdr->header),
1017 btrfs_stack_header_owner(
1018 &leafhdr->header));
1019 }
1020
1021 continue_with_current_leaf_stack_frame:
1022 if (0 == sf->num_copies || sf->mirror_num > sf->num_copies) {
1023 sf->i++;
1024 sf->num_copies = 0;
1025 }
1026
1027 if (sf->i < sf->nr) {
1028 struct btrfs_item disk_item;
1029 u32 disk_item_offset =
1030 (uintptr_t)(leafhdr->items + sf->i) -
1031 (uintptr_t)leafhdr;
1032 struct btrfs_disk_key *disk_key;
1033 u8 type;
1034 u32 item_offset;
1035 u32 item_size;
1036
1037 if (disk_item_offset + sizeof(struct btrfs_item) >
1038 sf->block_ctx->len) {
1039 leaf_item_out_of_bounce_error:
1040 printk(KERN_INFO
1041 "btrfsic: leaf item out of bounce at logical %llu, dev %s\n",
1042 sf->block_ctx->start,
1043 sf->block_ctx->dev->name);
1044 goto one_stack_frame_backwards;
1045 }
1046 btrfsic_read_from_block_data(sf->block_ctx,
1047 &disk_item,
1048 disk_item_offset,
1049 sizeof(struct btrfs_item));
1050 item_offset = btrfs_stack_item_offset(&disk_item);
1051 item_size = btrfs_stack_item_size(&disk_item);
1052 disk_key = &disk_item.key;
1053 type = btrfs_disk_key_type(disk_key);
1054
1055 if (BTRFS_ROOT_ITEM_KEY == type) {
1056 struct btrfs_root_item root_item;
1057 u32 root_item_offset;
1058 u64 next_bytenr;
1059
1060 root_item_offset = item_offset +
1061 offsetof(struct btrfs_leaf, items);
1062 if (root_item_offset + item_size >
1063 sf->block_ctx->len)
1064 goto leaf_item_out_of_bounce_error;
1065 btrfsic_read_from_block_data(
1066 sf->block_ctx, &root_item,
1067 root_item_offset,
1068 item_size);
1069 next_bytenr = btrfs_root_bytenr(&root_item);
1070
1071 sf->error =
1072 btrfsic_create_link_to_next_block(
1073 state,
1074 sf->block,
1075 sf->block_ctx,
1076 next_bytenr,
1077 sf->limit_nesting,
1078 &sf->next_block_ctx,
1079 &sf->next_block,
1080 force_iodone_flag,
1081 &sf->num_copies,
1082 &sf->mirror_num,
1083 disk_key,
1084 btrfs_root_generation(
1085 &root_item));
1086 if (sf->error)
1087 goto one_stack_frame_backwards;
1088
1089 if (NULL != sf->next_block) {
1090 struct btrfs_header *const next_hdr =
1091 (struct btrfs_header *)
1092 sf->next_block_ctx.datav[0];
1093
1094 next_stack =
1095 btrfsic_stack_frame_alloc();
1096 if (NULL == next_stack) {
1097 btrfsic_release_block_ctx(
1098 &sf->
1099 next_block_ctx);
1100 goto one_stack_frame_backwards;
1101 }
1102
1103 next_stack->i = -1;
1104 next_stack->block = sf->next_block;
1105 next_stack->block_ctx =
1106 &sf->next_block_ctx;
1107 next_stack->next_block = NULL;
1108 next_stack->hdr = next_hdr;
1109 next_stack->limit_nesting =
1110 sf->limit_nesting - 1;
1111 next_stack->prev = sf;
1112 sf = next_stack;
1113 goto continue_with_new_stack_frame;
1114 }
1115 } else if (BTRFS_EXTENT_DATA_KEY == type &&
1116 state->include_extent_data) {
1117 sf->error = btrfsic_handle_extent_data(
1118 state,
1119 sf->block,
1120 sf->block_ctx,
1121 item_offset,
1122 force_iodone_flag);
1123 if (sf->error)
1124 goto one_stack_frame_backwards;
1125 }
1126
1127 goto continue_with_current_leaf_stack_frame;
1128 }
1129 } else {
1130 struct btrfs_node *const nodehdr = (struct btrfs_node *)sf->hdr;
1131
1132 if (-1 == sf->i) {
1133 sf->nr = btrfs_stack_header_nritems(&nodehdr->header);
1134
1135 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1136 printk(KERN_INFO "node %llu level %d items %d"
1137 " generation %llu owner %llu\n",
1138 sf->block_ctx->start,
1139 nodehdr->header.level, sf->nr,
1140 btrfs_stack_header_generation(
1141 &nodehdr->header),
1142 btrfs_stack_header_owner(
1143 &nodehdr->header));
1144 }
1145
1146 continue_with_current_node_stack_frame:
1147 if (0 == sf->num_copies || sf->mirror_num > sf->num_copies) {
1148 sf->i++;
1149 sf->num_copies = 0;
1150 }
1151
1152 if (sf->i < sf->nr) {
1153 struct btrfs_key_ptr key_ptr;
1154 u32 key_ptr_offset;
1155 u64 next_bytenr;
1156
1157 key_ptr_offset = (uintptr_t)(nodehdr->ptrs + sf->i) -
1158 (uintptr_t)nodehdr;
1159 if (key_ptr_offset + sizeof(struct btrfs_key_ptr) >
1160 sf->block_ctx->len) {
1161 printk(KERN_INFO
1162 "btrfsic: node item out of bounce at logical %llu, dev %s\n",
1163 sf->block_ctx->start,
1164 sf->block_ctx->dev->name);
1165 goto one_stack_frame_backwards;
1166 }
1167 btrfsic_read_from_block_data(
1168 sf->block_ctx, &key_ptr, key_ptr_offset,
1169 sizeof(struct btrfs_key_ptr));
1170 next_bytenr = btrfs_stack_key_blockptr(&key_ptr);
1171
1172 sf->error = btrfsic_create_link_to_next_block(
1173 state,
1174 sf->block,
1175 sf->block_ctx,
1176 next_bytenr,
1177 sf->limit_nesting,
1178 &sf->next_block_ctx,
1179 &sf->next_block,
1180 force_iodone_flag,
1181 &sf->num_copies,
1182 &sf->mirror_num,
1183 &key_ptr.key,
1184 btrfs_stack_key_generation(&key_ptr));
1185 if (sf->error)
1186 goto one_stack_frame_backwards;
1187
1188 if (NULL != sf->next_block) {
1189 struct btrfs_header *const next_hdr =
1190 (struct btrfs_header *)
1191 sf->next_block_ctx.datav[0];
1192
1193 next_stack = btrfsic_stack_frame_alloc();
1194 if (NULL == next_stack)
1195 goto one_stack_frame_backwards;
1196
1197 next_stack->i = -1;
1198 next_stack->block = sf->next_block;
1199 next_stack->block_ctx = &sf->next_block_ctx;
1200 next_stack->next_block = NULL;
1201 next_stack->hdr = next_hdr;
1202 next_stack->limit_nesting =
1203 sf->limit_nesting - 1;
1204 next_stack->prev = sf;
1205 sf = next_stack;
1206 goto continue_with_new_stack_frame;
1207 }
1208
1209 goto continue_with_current_node_stack_frame;
1210 }
1211 }
1212
1213 one_stack_frame_backwards:
1214 if (NULL != sf->prev) {
1215 struct btrfsic_stack_frame *const prev = sf->prev;
1216
1217 /* the one for the initial block is freed in the caller */
1218 btrfsic_release_block_ctx(sf->block_ctx);
1219
1220 if (sf->error) {
1221 prev->error = sf->error;
1222 btrfsic_stack_frame_free(sf);
1223 sf = prev;
1224 goto one_stack_frame_backwards;
1225 }
1226
1227 btrfsic_stack_frame_free(sf);
1228 sf = prev;
1229 goto continue_with_new_stack_frame;
1230 } else {
1231 BUG_ON(&initial_stack_frame != sf);
1232 }
1233
1234 return sf->error;
1235 }
1236
1237 static void btrfsic_read_from_block_data(
1238 struct btrfsic_block_data_ctx *block_ctx,
1239 void *dstv, u32 offset, size_t len)
1240 {
1241 size_t cur;
1242 size_t offset_in_page;
1243 char *kaddr;
1244 char *dst = (char *)dstv;
1245 size_t start_offset = block_ctx->start & ((u64)PAGE_CACHE_SIZE - 1);
1246 unsigned long i = (start_offset + offset) >> PAGE_CACHE_SHIFT;
1247
1248 WARN_ON(offset + len > block_ctx->len);
1249 offset_in_page = (start_offset + offset) & (PAGE_CACHE_SIZE - 1);
1250
1251 while (len > 0) {
1252 cur = min(len, ((size_t)PAGE_CACHE_SIZE - offset_in_page));
1253 BUG_ON(i >= (block_ctx->len + PAGE_CACHE_SIZE - 1) >>
1254 PAGE_CACHE_SHIFT);
1255 kaddr = block_ctx->datav[i];
1256 memcpy(dst, kaddr + offset_in_page, cur);
1257
1258 dst += cur;
1259 len -= cur;
1260 offset_in_page = 0;
1261 i++;
1262 }
1263 }
1264
1265 static int btrfsic_create_link_to_next_block(
1266 struct btrfsic_state *state,
1267 struct btrfsic_block *block,
1268 struct btrfsic_block_data_ctx *block_ctx,
1269 u64 next_bytenr,
1270 int limit_nesting,
1271 struct btrfsic_block_data_ctx *next_block_ctx,
1272 struct btrfsic_block **next_blockp,
1273 int force_iodone_flag,
1274 int *num_copiesp, int *mirror_nump,
1275 struct btrfs_disk_key *disk_key,
1276 u64 parent_generation)
1277 {
1278 struct btrfsic_block *next_block = NULL;
1279 int ret;
1280 struct btrfsic_block_link *l;
1281 int did_alloc_block_link;
1282 int block_was_created;
1283
1284 *next_blockp = NULL;
1285 if (0 == *num_copiesp) {
1286 *num_copiesp =
1287 btrfs_num_copies(state->root->fs_info,
1288 next_bytenr, state->metablock_size);
1289 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
1290 printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
1291 next_bytenr, *num_copiesp);
1292 *mirror_nump = 1;
1293 }
1294
1295 if (*mirror_nump > *num_copiesp)
1296 return 0;
1297
1298 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1299 printk(KERN_INFO
1300 "btrfsic_create_link_to_next_block(mirror_num=%d)\n",
1301 *mirror_nump);
1302 ret = btrfsic_map_block(state, next_bytenr,
1303 state->metablock_size,
1304 next_block_ctx, *mirror_nump);
1305 if (ret) {
1306 printk(KERN_INFO
1307 "btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n",
1308 next_bytenr, *mirror_nump);
1309 btrfsic_release_block_ctx(next_block_ctx);
1310 *next_blockp = NULL;
1311 return -1;
1312 }
1313
1314 next_block = btrfsic_block_lookup_or_add(state,
1315 next_block_ctx, "referenced ",
1316 1, force_iodone_flag,
1317 !force_iodone_flag,
1318 *mirror_nump,
1319 &block_was_created);
1320 if (NULL == next_block) {
1321 btrfsic_release_block_ctx(next_block_ctx);
1322 *next_blockp = NULL;
1323 return -1;
1324 }
1325 if (block_was_created) {
1326 l = NULL;
1327 next_block->generation = BTRFSIC_GENERATION_UNKNOWN;
1328 } else {
1329 if (next_block->logical_bytenr != next_bytenr &&
1330 !(!next_block->is_metadata &&
1331 0 == next_block->logical_bytenr)) {
1332 printk(KERN_INFO
1333 "Referenced block @%llu (%s/%llu/%d)"
1334 " found in hash table, %c,"
1335 " bytenr mismatch (!= stored %llu).\n",
1336 next_bytenr, next_block_ctx->dev->name,
1337 next_block_ctx->dev_bytenr, *mirror_nump,
1338 btrfsic_get_block_type(state, next_block),
1339 next_block->logical_bytenr);
1340 } else if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1341 printk(KERN_INFO
1342 "Referenced block @%llu (%s/%llu/%d)"
1343 " found in hash table, %c.\n",
1344 next_bytenr, next_block_ctx->dev->name,
1345 next_block_ctx->dev_bytenr, *mirror_nump,
1346 btrfsic_get_block_type(state, next_block));
1347 next_block->logical_bytenr = next_bytenr;
1348
1349 next_block->mirror_num = *mirror_nump;
1350 l = btrfsic_block_link_hashtable_lookup(
1351 next_block_ctx->dev->bdev,
1352 next_block_ctx->dev_bytenr,
1353 block_ctx->dev->bdev,
1354 block_ctx->dev_bytenr,
1355 &state->block_link_hashtable);
1356 }
1357
1358 next_block->disk_key = *disk_key;
1359 if (NULL == l) {
1360 l = btrfsic_block_link_alloc();
1361 if (NULL == l) {
1362 printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
1363 btrfsic_release_block_ctx(next_block_ctx);
1364 *next_blockp = NULL;
1365 return -1;
1366 }
1367
1368 did_alloc_block_link = 1;
1369 l->block_ref_to = next_block;
1370 l->block_ref_from = block;
1371 l->ref_cnt = 1;
1372 l->parent_generation = parent_generation;
1373
1374 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1375 btrfsic_print_add_link(state, l);
1376
1377 list_add(&l->node_ref_to, &block->ref_to_list);
1378 list_add(&l->node_ref_from, &next_block->ref_from_list);
1379
1380 btrfsic_block_link_hashtable_add(l,
1381 &state->block_link_hashtable);
1382 } else {
1383 did_alloc_block_link = 0;
1384 if (0 == limit_nesting) {
1385 l->ref_cnt++;
1386 l->parent_generation = parent_generation;
1387 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1388 btrfsic_print_add_link(state, l);
1389 }
1390 }
1391
1392 if (limit_nesting > 0 && did_alloc_block_link) {
1393 ret = btrfsic_read_block(state, next_block_ctx);
1394 if (ret < (int)next_block_ctx->len) {
1395 printk(KERN_INFO
1396 "btrfsic: read block @logical %llu failed!\n",
1397 next_bytenr);
1398 btrfsic_release_block_ctx(next_block_ctx);
1399 *next_blockp = NULL;
1400 return -1;
1401 }
1402
1403 *next_blockp = next_block;
1404 } else {
1405 *next_blockp = NULL;
1406 }
1407 (*mirror_nump)++;
1408
1409 return 0;
1410 }
1411
1412 static int btrfsic_handle_extent_data(
1413 struct btrfsic_state *state,
1414 struct btrfsic_block *block,
1415 struct btrfsic_block_data_ctx *block_ctx,
1416 u32 item_offset, int force_iodone_flag)
1417 {
1418 int ret;
1419 struct btrfs_file_extent_item file_extent_item;
1420 u64 file_extent_item_offset;
1421 u64 next_bytenr;
1422 u64 num_bytes;
1423 u64 generation;
1424 struct btrfsic_block_link *l;
1425
1426 file_extent_item_offset = offsetof(struct btrfs_leaf, items) +
1427 item_offset;
1428 if (file_extent_item_offset +
1429 offsetof(struct btrfs_file_extent_item, disk_num_bytes) >
1430 block_ctx->len) {
1431 printk(KERN_INFO
1432 "btrfsic: file item out of bounce at logical %llu, dev %s\n",
1433 block_ctx->start, block_ctx->dev->name);
1434 return -1;
1435 }
1436
1437 btrfsic_read_from_block_data(block_ctx, &file_extent_item,
1438 file_extent_item_offset,
1439 offsetof(struct btrfs_file_extent_item, disk_num_bytes));
1440 if (BTRFS_FILE_EXTENT_REG != file_extent_item.type ||
1441 btrfs_stack_file_extent_disk_bytenr(&file_extent_item) == 0) {
1442 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE)
1443 printk(KERN_INFO "extent_data: type %u, disk_bytenr = %llu\n",
1444 file_extent_item.type,
1445 btrfs_stack_file_extent_disk_bytenr(
1446 &file_extent_item));
1447 return 0;
1448 }
1449
1450 if (file_extent_item_offset + sizeof(struct btrfs_file_extent_item) >
1451 block_ctx->len) {
1452 printk(KERN_INFO
1453 "btrfsic: file item out of bounce at logical %llu, dev %s\n",
1454 block_ctx->start, block_ctx->dev->name);
1455 return -1;
1456 }
1457 btrfsic_read_from_block_data(block_ctx, &file_extent_item,
1458 file_extent_item_offset,
1459 sizeof(struct btrfs_file_extent_item));
1460 next_bytenr = btrfs_stack_file_extent_disk_bytenr(&file_extent_item) +
1461 btrfs_stack_file_extent_offset(&file_extent_item);
1462 generation = btrfs_stack_file_extent_generation(&file_extent_item);
1463 num_bytes = btrfs_stack_file_extent_num_bytes(&file_extent_item);
1464 generation = btrfs_stack_file_extent_generation(&file_extent_item);
1465
1466 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE)
1467 printk(KERN_INFO "extent_data: type %u, disk_bytenr = %llu,"
1468 " offset = %llu, num_bytes = %llu\n",
1469 file_extent_item.type,
1470 btrfs_stack_file_extent_disk_bytenr(&file_extent_item),
1471 btrfs_stack_file_extent_offset(&file_extent_item),
1472 num_bytes);
1473 while (num_bytes > 0) {
1474 u32 chunk_len;
1475 int num_copies;
1476 int mirror_num;
1477
1478 if (num_bytes > state->datablock_size)
1479 chunk_len = state->datablock_size;
1480 else
1481 chunk_len = num_bytes;
1482
1483 num_copies =
1484 btrfs_num_copies(state->root->fs_info,
1485 next_bytenr, state->datablock_size);
1486 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
1487 printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
1488 next_bytenr, num_copies);
1489 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
1490 struct btrfsic_block_data_ctx next_block_ctx;
1491 struct btrfsic_block *next_block;
1492 int block_was_created;
1493
1494 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1495 printk(KERN_INFO "btrfsic_handle_extent_data("
1496 "mirror_num=%d)\n", mirror_num);
1497 if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE)
1498 printk(KERN_INFO
1499 "\tdisk_bytenr = %llu, num_bytes %u\n",
1500 next_bytenr, chunk_len);
1501 ret = btrfsic_map_block(state, next_bytenr,
1502 chunk_len, &next_block_ctx,
1503 mirror_num);
1504 if (ret) {
1505 printk(KERN_INFO
1506 "btrfsic: btrfsic_map_block(@%llu,"
1507 " mirror=%d) failed!\n",
1508 next_bytenr, mirror_num);
1509 return -1;
1510 }
1511
1512 next_block = btrfsic_block_lookup_or_add(
1513 state,
1514 &next_block_ctx,
1515 "referenced ",
1516 0,
1517 force_iodone_flag,
1518 !force_iodone_flag,
1519 mirror_num,
1520 &block_was_created);
1521 if (NULL == next_block) {
1522 printk(KERN_INFO
1523 "btrfsic: error, kmalloc failed!\n");
1524 btrfsic_release_block_ctx(&next_block_ctx);
1525 return -1;
1526 }
1527 if (!block_was_created) {
1528 if (next_block->logical_bytenr != next_bytenr &&
1529 !(!next_block->is_metadata &&
1530 0 == next_block->logical_bytenr)) {
1531 printk(KERN_INFO
1532 "Referenced block"
1533 " @%llu (%s/%llu/%d)"
1534 " found in hash table, D,"
1535 " bytenr mismatch"
1536 " (!= stored %llu).\n",
1537 next_bytenr,
1538 next_block_ctx.dev->name,
1539 next_block_ctx.dev_bytenr,
1540 mirror_num,
1541 next_block->logical_bytenr);
1542 }
1543 next_block->logical_bytenr = next_bytenr;
1544 next_block->mirror_num = mirror_num;
1545 }
1546
1547 l = btrfsic_block_link_lookup_or_add(state,
1548 &next_block_ctx,
1549 next_block, block,
1550 generation);
1551 btrfsic_release_block_ctx(&next_block_ctx);
1552 if (NULL == l)
1553 return -1;
1554 }
1555
1556 next_bytenr += chunk_len;
1557 num_bytes -= chunk_len;
1558 }
1559
1560 return 0;
1561 }
1562
1563 static int btrfsic_map_block(struct btrfsic_state *state, u64 bytenr, u32 len,
1564 struct btrfsic_block_data_ctx *block_ctx_out,
1565 int mirror_num)
1566 {
1567 int ret;
1568 u64 length;
1569 struct btrfs_bio *multi = NULL;
1570 struct btrfs_device *device;
1571
1572 length = len;
1573 ret = btrfs_map_block(state->root->fs_info, READ,
1574 bytenr, &length, &multi, mirror_num);
1575
1576 if (ret) {
1577 block_ctx_out->start = 0;
1578 block_ctx_out->dev_bytenr = 0;
1579 block_ctx_out->len = 0;
1580 block_ctx_out->dev = NULL;
1581 block_ctx_out->datav = NULL;
1582 block_ctx_out->pagev = NULL;
1583 block_ctx_out->mem_to_free = NULL;
1584
1585 return ret;
1586 }
1587
1588 device = multi->stripes[0].dev;
1589 block_ctx_out->dev = btrfsic_dev_state_lookup(device->bdev);
1590 block_ctx_out->dev_bytenr = multi->stripes[0].physical;
1591 block_ctx_out->start = bytenr;
1592 block_ctx_out->len = len;
1593 block_ctx_out->datav = NULL;
1594 block_ctx_out->pagev = NULL;
1595 block_ctx_out->mem_to_free = NULL;
1596
1597 kfree(multi);
1598 if (NULL == block_ctx_out->dev) {
1599 ret = -ENXIO;
1600 printk(KERN_INFO "btrfsic: error, cannot lookup dev (#1)!\n");
1601 }
1602
1603 return ret;
1604 }
1605
1606 static int btrfsic_map_superblock(struct btrfsic_state *state, u64 bytenr,
1607 u32 len, struct block_device *bdev,
1608 struct btrfsic_block_data_ctx *block_ctx_out)
1609 {
1610 block_ctx_out->dev = btrfsic_dev_state_lookup(bdev);
1611 block_ctx_out->dev_bytenr = bytenr;
1612 block_ctx_out->start = bytenr;
1613 block_ctx_out->len = len;
1614 block_ctx_out->datav = NULL;
1615 block_ctx_out->pagev = NULL;
1616 block_ctx_out->mem_to_free = NULL;
1617 if (NULL != block_ctx_out->dev) {
1618 return 0;
1619 } else {
1620 printk(KERN_INFO "btrfsic: error, cannot lookup dev (#2)!\n");
1621 return -ENXIO;
1622 }
1623 }
1624
1625 static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx)
1626 {
1627 if (block_ctx->mem_to_free) {
1628 unsigned int num_pages;
1629
1630 BUG_ON(!block_ctx->datav);
1631 BUG_ON(!block_ctx->pagev);
1632 num_pages = (block_ctx->len + (u64)PAGE_CACHE_SIZE - 1) >>
1633 PAGE_CACHE_SHIFT;
1634 while (num_pages > 0) {
1635 num_pages--;
1636 if (block_ctx->datav[num_pages]) {
1637 kunmap(block_ctx->pagev[num_pages]);
1638 block_ctx->datav[num_pages] = NULL;
1639 }
1640 if (block_ctx->pagev[num_pages]) {
1641 __free_page(block_ctx->pagev[num_pages]);
1642 block_ctx->pagev[num_pages] = NULL;
1643 }
1644 }
1645
1646 kfree(block_ctx->mem_to_free);
1647 block_ctx->mem_to_free = NULL;
1648 block_ctx->pagev = NULL;
1649 block_ctx->datav = NULL;
1650 }
1651 }
1652
1653 static int btrfsic_read_block(struct btrfsic_state *state,
1654 struct btrfsic_block_data_ctx *block_ctx)
1655 {
1656 unsigned int num_pages;
1657 unsigned int i;
1658 u64 dev_bytenr;
1659 int ret;
1660
1661 BUG_ON(block_ctx->datav);
1662 BUG_ON(block_ctx->pagev);
1663 BUG_ON(block_ctx->mem_to_free);
1664 if (block_ctx->dev_bytenr & ((u64)PAGE_CACHE_SIZE - 1)) {
1665 printk(KERN_INFO
1666 "btrfsic: read_block() with unaligned bytenr %llu\n",
1667 block_ctx->dev_bytenr);
1668 return -1;
1669 }
1670
1671 num_pages = (block_ctx->len + (u64)PAGE_CACHE_SIZE - 1) >>
1672 PAGE_CACHE_SHIFT;
1673 block_ctx->mem_to_free = kzalloc((sizeof(*block_ctx->datav) +
1674 sizeof(*block_ctx->pagev)) *
1675 num_pages, GFP_NOFS);
1676 if (!block_ctx->mem_to_free)
1677 return -1;
1678 block_ctx->datav = block_ctx->mem_to_free;
1679 block_ctx->pagev = (struct page **)(block_ctx->datav + num_pages);
1680 for (i = 0; i < num_pages; i++) {
1681 block_ctx->pagev[i] = alloc_page(GFP_NOFS);
1682 if (!block_ctx->pagev[i])
1683 return -1;
1684 }
1685
1686 dev_bytenr = block_ctx->dev_bytenr;
1687 for (i = 0; i < num_pages;) {
1688 struct bio *bio;
1689 unsigned int j;
1690 DECLARE_COMPLETION_ONSTACK(complete);
1691
1692 bio = btrfs_io_bio_alloc(GFP_NOFS, num_pages - i);
1693 if (!bio) {
1694 printk(KERN_INFO
1695 "btrfsic: bio_alloc() for %u pages failed!\n",
1696 num_pages - i);
1697 return -1;
1698 }
1699 bio->bi_bdev = block_ctx->dev->bdev;
1700 bio->bi_sector = dev_bytenr >> 9;
1701 bio->bi_end_io = btrfsic_complete_bio_end_io;
1702 bio->bi_private = &complete;
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 submit_bio(READ, bio);
1716
1717 /* this will also unplug the queue */
1718 wait_for_completion(&complete);
1719
1720 if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) {
1721 printk(KERN_INFO
1722 "btrfsic: read error at logical %llu dev %s!\n",
1723 block_ctx->start, block_ctx->dev->name);
1724 bio_put(bio);
1725 return -1;
1726 }
1727 bio_put(bio);
1728 dev_bytenr += (j - i) * PAGE_CACHE_SIZE;
1729 i = j;
1730 }
1731 for (i = 0; i < num_pages; i++) {
1732 block_ctx->datav[i] = kmap(block_ctx->pagev[i]);
1733 if (!block_ctx->datav[i]) {
1734 printk(KERN_INFO "btrfsic: kmap() failed (dev %s)!\n",
1735 block_ctx->dev->name);
1736 return -1;
1737 }
1738 }
1739
1740 return block_ctx->len;
1741 }
1742
1743 static void btrfsic_complete_bio_end_io(struct bio *bio, int err)
1744 {
1745 complete((struct completion *)bio->bi_private);
1746 }
1747
1748 static void btrfsic_dump_database(struct btrfsic_state *state)
1749 {
1750 struct list_head *elem_all;
1751
1752 BUG_ON(NULL == state);
1753
1754 printk(KERN_INFO "all_blocks_list:\n");
1755 list_for_each(elem_all, &state->all_blocks_list) {
1756 const struct btrfsic_block *const b_all =
1757 list_entry(elem_all, struct btrfsic_block,
1758 all_blocks_node);
1759 struct list_head *elem_ref_to;
1760 struct list_head *elem_ref_from;
1761
1762 printk(KERN_INFO "%c-block @%llu (%s/%llu/%d)\n",
1763 btrfsic_get_block_type(state, b_all),
1764 b_all->logical_bytenr, b_all->dev_state->name,
1765 b_all->dev_bytenr, b_all->mirror_num);
1766
1767 list_for_each(elem_ref_to, &b_all->ref_to_list) {
1768 const struct btrfsic_block_link *const l =
1769 list_entry(elem_ref_to,
1770 struct btrfsic_block_link,
1771 node_ref_to);
1772
1773 printk(KERN_INFO " %c @%llu (%s/%llu/%d)"
1774 " refers %u* to"
1775 " %c @%llu (%s/%llu/%d)\n",
1776 btrfsic_get_block_type(state, b_all),
1777 b_all->logical_bytenr, b_all->dev_state->name,
1778 b_all->dev_bytenr, b_all->mirror_num,
1779 l->ref_cnt,
1780 btrfsic_get_block_type(state, l->block_ref_to),
1781 l->block_ref_to->logical_bytenr,
1782 l->block_ref_to->dev_state->name,
1783 l->block_ref_to->dev_bytenr,
1784 l->block_ref_to->mirror_num);
1785 }
1786
1787 list_for_each(elem_ref_from, &b_all->ref_from_list) {
1788 const struct btrfsic_block_link *const l =
1789 list_entry(elem_ref_from,
1790 struct btrfsic_block_link,
1791 node_ref_from);
1792
1793 printk(KERN_INFO " %c @%llu (%s/%llu/%d)"
1794 " is ref %u* from"
1795 " %c @%llu (%s/%llu/%d)\n",
1796 btrfsic_get_block_type(state, b_all),
1797 b_all->logical_bytenr, b_all->dev_state->name,
1798 b_all->dev_bytenr, b_all->mirror_num,
1799 l->ref_cnt,
1800 btrfsic_get_block_type(state, l->block_ref_from),
1801 l->block_ref_from->logical_bytenr,
1802 l->block_ref_from->dev_state->name,
1803 l->block_ref_from->dev_bytenr,
1804 l->block_ref_from->mirror_num);
1805 }
1806
1807 printk(KERN_INFO "\n");
1808 }
1809 }
1810
1811 /*
1812 * Test whether the disk block contains a tree block (leaf or node)
1813 * (note that this test fails for the super block)
1814 */
1815 static int btrfsic_test_for_metadata(struct btrfsic_state *state,
1816 char **datav, unsigned int num_pages)
1817 {
1818 struct btrfs_header *h;
1819 u8 csum[BTRFS_CSUM_SIZE];
1820 u32 crc = ~(u32)0;
1821 unsigned int i;
1822
1823 if (num_pages * PAGE_CACHE_SIZE < state->metablock_size)
1824 return 1; /* not metadata */
1825 num_pages = state->metablock_size >> PAGE_CACHE_SHIFT;
1826 h = (struct btrfs_header *)datav[0];
1827
1828 if (memcmp(h->fsid, state->root->fs_info->fsid, BTRFS_UUID_SIZE))
1829 return 1;
1830
1831 for (i = 0; i < num_pages; i++) {
1832 u8 *data = i ? datav[i] : (datav[i] + BTRFS_CSUM_SIZE);
1833 size_t sublen = i ? PAGE_CACHE_SIZE :
1834 (PAGE_CACHE_SIZE - BTRFS_CSUM_SIZE);
1835
1836 crc = crc32c(crc, data, sublen);
1837 }
1838 btrfs_csum_final(crc, csum);
1839 if (memcmp(csum, h->csum, state->csum_size))
1840 return 1;
1841
1842 return 0; /* is metadata */
1843 }
1844
1845 static void btrfsic_process_written_block(struct btrfsic_dev_state *dev_state,
1846 u64 dev_bytenr, char **mapped_datav,
1847 unsigned int num_pages,
1848 struct bio *bio, int *bio_is_patched,
1849 struct buffer_head *bh,
1850 int submit_bio_bh_rw)
1851 {
1852 int is_metadata;
1853 struct btrfsic_block *block;
1854 struct btrfsic_block_data_ctx block_ctx;
1855 int ret;
1856 struct btrfsic_state *state = dev_state->state;
1857 struct block_device *bdev = dev_state->bdev;
1858 unsigned int processed_len;
1859
1860 if (NULL != bio_is_patched)
1861 *bio_is_patched = 0;
1862
1863 again:
1864 if (num_pages == 0)
1865 return;
1866
1867 processed_len = 0;
1868 is_metadata = (0 == btrfsic_test_for_metadata(state, mapped_datav,
1869 num_pages));
1870
1871 block = btrfsic_block_hashtable_lookup(bdev, dev_bytenr,
1872 &state->block_hashtable);
1873 if (NULL != block) {
1874 u64 bytenr = 0;
1875 struct list_head *elem_ref_to;
1876 struct list_head *tmp_ref_to;
1877
1878 if (block->is_superblock) {
1879 bytenr = btrfs_super_bytenr((struct btrfs_super_block *)
1880 mapped_datav[0]);
1881 if (num_pages * PAGE_CACHE_SIZE <
1882 BTRFS_SUPER_INFO_SIZE) {
1883 printk(KERN_INFO
1884 "btrfsic: cannot work with too short bios!\n");
1885 return;
1886 }
1887 is_metadata = 1;
1888 BUG_ON(BTRFS_SUPER_INFO_SIZE & (PAGE_CACHE_SIZE - 1));
1889 processed_len = BTRFS_SUPER_INFO_SIZE;
1890 if (state->print_mask &
1891 BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE) {
1892 printk(KERN_INFO
1893 "[before new superblock is written]:\n");
1894 btrfsic_dump_tree_sub(state, block, 0);
1895 }
1896 }
1897 if (is_metadata) {
1898 if (!block->is_superblock) {
1899 if (num_pages * PAGE_CACHE_SIZE <
1900 state->metablock_size) {
1901 printk(KERN_INFO
1902 "btrfsic: cannot work with too short bios!\n");
1903 return;
1904 }
1905 processed_len = state->metablock_size;
1906 bytenr = btrfs_stack_header_bytenr(
1907 (struct btrfs_header *)
1908 mapped_datav[0]);
1909 btrfsic_cmp_log_and_dev_bytenr(state, bytenr,
1910 dev_state,
1911 dev_bytenr);
1912 }
1913 if (block->logical_bytenr != bytenr &&
1914 !(!block->is_metadata &&
1915 block->logical_bytenr == 0))
1916 printk(KERN_INFO
1917 "Written block @%llu (%s/%llu/%d)"
1918 " found in hash table, %c,"
1919 " bytenr mismatch"
1920 " (!= stored %llu).\n",
1921 bytenr, dev_state->name, dev_bytenr,
1922 block->mirror_num,
1923 btrfsic_get_block_type(state, block),
1924 block->logical_bytenr);
1925 else if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1926 printk(KERN_INFO
1927 "Written block @%llu (%s/%llu/%d)"
1928 " found in hash table, %c.\n",
1929 bytenr, dev_state->name, dev_bytenr,
1930 block->mirror_num,
1931 btrfsic_get_block_type(state, block));
1932 block->logical_bytenr = bytenr;
1933 } else {
1934 if (num_pages * PAGE_CACHE_SIZE <
1935 state->datablock_size) {
1936 printk(KERN_INFO
1937 "btrfsic: cannot work with too short bios!\n");
1938 return;
1939 }
1940 processed_len = state->datablock_size;
1941 bytenr = block->logical_bytenr;
1942 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1943 printk(KERN_INFO
1944 "Written block @%llu (%s/%llu/%d)"
1945 " found in hash table, %c.\n",
1946 bytenr, dev_state->name, dev_bytenr,
1947 block->mirror_num,
1948 btrfsic_get_block_type(state, block));
1949 }
1950
1951 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
1952 printk(KERN_INFO
1953 "ref_to_list: %cE, ref_from_list: %cE\n",
1954 list_empty(&block->ref_to_list) ? ' ' : '!',
1955 list_empty(&block->ref_from_list) ? ' ' : '!');
1956 if (btrfsic_is_block_ref_by_superblock(state, block, 0)) {
1957 printk(KERN_INFO "btrfs: attempt to overwrite %c-block"
1958 " @%llu (%s/%llu/%d), old(gen=%llu,"
1959 " objectid=%llu, type=%d, offset=%llu),"
1960 " new(gen=%llu),"
1961 " which is referenced by most recent superblock"
1962 " (superblockgen=%llu)!\n",
1963 btrfsic_get_block_type(state, block), bytenr,
1964 dev_state->name, dev_bytenr, block->mirror_num,
1965 block->generation,
1966 btrfs_disk_key_objectid(&block->disk_key),
1967 block->disk_key.type,
1968 btrfs_disk_key_offset(&block->disk_key),
1969 btrfs_stack_header_generation(
1970 (struct btrfs_header *) mapped_datav[0]),
1971 state->max_superblock_generation);
1972 btrfsic_dump_tree(state);
1973 }
1974
1975 if (!block->is_iodone && !block->never_written) {
1976 printk(KERN_INFO "btrfs: attempt to overwrite %c-block"
1977 " @%llu (%s/%llu/%d), oldgen=%llu, newgen=%llu,"
1978 " which is not yet iodone!\n",
1979 btrfsic_get_block_type(state, block), bytenr,
1980 dev_state->name, dev_bytenr, block->mirror_num,
1981 block->generation,
1982 btrfs_stack_header_generation(
1983 (struct btrfs_header *)
1984 mapped_datav[0]));
1985 /* it would not be safe to go on */
1986 btrfsic_dump_tree(state);
1987 goto continue_loop;
1988 }
1989
1990 /*
1991 * Clear all references of this block. Do not free
1992 * the block itself even if is not referenced anymore
1993 * because it still carries valueable information
1994 * like whether it was ever written and IO completed.
1995 */
1996 list_for_each_safe(elem_ref_to, tmp_ref_to,
1997 &block->ref_to_list) {
1998 struct btrfsic_block_link *const l =
1999 list_entry(elem_ref_to,
2000 struct btrfsic_block_link,
2001 node_ref_to);
2002
2003 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2004 btrfsic_print_rem_link(state, l);
2005 l->ref_cnt--;
2006 if (0 == l->ref_cnt) {
2007 list_del(&l->node_ref_to);
2008 list_del(&l->node_ref_from);
2009 btrfsic_block_link_hashtable_remove(l);
2010 btrfsic_block_link_free(l);
2011 }
2012 }
2013
2014 if (block->is_superblock)
2015 ret = btrfsic_map_superblock(state, bytenr,
2016 processed_len,
2017 bdev, &block_ctx);
2018 else
2019 ret = btrfsic_map_block(state, bytenr, processed_len,
2020 &block_ctx, 0);
2021 if (ret) {
2022 printk(KERN_INFO
2023 "btrfsic: btrfsic_map_block(root @%llu)"
2024 " failed!\n", bytenr);
2025 goto continue_loop;
2026 }
2027 block_ctx.datav = mapped_datav;
2028 /* the following is required in case of writes to mirrors,
2029 * use the same that was used for the lookup */
2030 block_ctx.dev = dev_state;
2031 block_ctx.dev_bytenr = dev_bytenr;
2032
2033 if (is_metadata || state->include_extent_data) {
2034 block->never_written = 0;
2035 block->iodone_w_error = 0;
2036 if (NULL != bio) {
2037 block->is_iodone = 0;
2038 BUG_ON(NULL == bio_is_patched);
2039 if (!*bio_is_patched) {
2040 block->orig_bio_bh_private =
2041 bio->bi_private;
2042 block->orig_bio_bh_end_io.bio =
2043 bio->bi_end_io;
2044 block->next_in_same_bio = NULL;
2045 bio->bi_private = block;
2046 bio->bi_end_io = btrfsic_bio_end_io;
2047 *bio_is_patched = 1;
2048 } else {
2049 struct btrfsic_block *chained_block =
2050 (struct btrfsic_block *)
2051 bio->bi_private;
2052
2053 BUG_ON(NULL == chained_block);
2054 block->orig_bio_bh_private =
2055 chained_block->orig_bio_bh_private;
2056 block->orig_bio_bh_end_io.bio =
2057 chained_block->orig_bio_bh_end_io.
2058 bio;
2059 block->next_in_same_bio = chained_block;
2060 bio->bi_private = block;
2061 }
2062 } else if (NULL != bh) {
2063 block->is_iodone = 0;
2064 block->orig_bio_bh_private = bh->b_private;
2065 block->orig_bio_bh_end_io.bh = bh->b_end_io;
2066 block->next_in_same_bio = NULL;
2067 bh->b_private = block;
2068 bh->b_end_io = btrfsic_bh_end_io;
2069 } else {
2070 block->is_iodone = 1;
2071 block->orig_bio_bh_private = NULL;
2072 block->orig_bio_bh_end_io.bio = NULL;
2073 block->next_in_same_bio = NULL;
2074 }
2075 }
2076
2077 block->flush_gen = dev_state->last_flush_gen + 1;
2078 block->submit_bio_bh_rw = submit_bio_bh_rw;
2079 if (is_metadata) {
2080 block->logical_bytenr = bytenr;
2081 block->is_metadata = 1;
2082 if (block->is_superblock) {
2083 BUG_ON(PAGE_CACHE_SIZE !=
2084 BTRFS_SUPER_INFO_SIZE);
2085 ret = btrfsic_process_written_superblock(
2086 state,
2087 block,
2088 (struct btrfs_super_block *)
2089 mapped_datav[0]);
2090 if (state->print_mask &
2091 BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE) {
2092 printk(KERN_INFO
2093 "[after new superblock is written]:\n");
2094 btrfsic_dump_tree_sub(state, block, 0);
2095 }
2096 } else {
2097 block->mirror_num = 0; /* unknown */
2098 ret = btrfsic_process_metablock(
2099 state,
2100 block,
2101 &block_ctx,
2102 0, 0);
2103 }
2104 if (ret)
2105 printk(KERN_INFO
2106 "btrfsic: btrfsic_process_metablock"
2107 "(root @%llu) failed!\n",
2108 dev_bytenr);
2109 } else {
2110 block->is_metadata = 0;
2111 block->mirror_num = 0; /* unknown */
2112 block->generation = BTRFSIC_GENERATION_UNKNOWN;
2113 if (!state->include_extent_data
2114 && list_empty(&block->ref_from_list)) {
2115 /*
2116 * disk block is overwritten with extent
2117 * data (not meta data) and we are configured
2118 * to not include extent data: take the
2119 * chance and free the block's memory
2120 */
2121 btrfsic_block_hashtable_remove(block);
2122 list_del(&block->all_blocks_node);
2123 btrfsic_block_free(block);
2124 }
2125 }
2126 btrfsic_release_block_ctx(&block_ctx);
2127 } else {
2128 /* block has not been found in hash table */
2129 u64 bytenr;
2130
2131 if (!is_metadata) {
2132 processed_len = state->datablock_size;
2133 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2134 printk(KERN_INFO "Written block (%s/%llu/?)"
2135 " !found in hash table, D.\n",
2136 dev_state->name, dev_bytenr);
2137 if (!state->include_extent_data) {
2138 /* ignore that written D block */
2139 goto continue_loop;
2140 }
2141
2142 /* this is getting ugly for the
2143 * include_extent_data case... */
2144 bytenr = 0; /* unknown */
2145 block_ctx.start = bytenr;
2146 block_ctx.len = processed_len;
2147 block_ctx.mem_to_free = NULL;
2148 block_ctx.pagev = NULL;
2149 } else {
2150 processed_len = state->metablock_size;
2151 bytenr = btrfs_stack_header_bytenr(
2152 (struct btrfs_header *)
2153 mapped_datav[0]);
2154 btrfsic_cmp_log_and_dev_bytenr(state, bytenr, dev_state,
2155 dev_bytenr);
2156 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2157 printk(KERN_INFO
2158 "Written block @%llu (%s/%llu/?)"
2159 " !found in hash table, M.\n",
2160 bytenr, dev_state->name, dev_bytenr);
2161
2162 ret = btrfsic_map_block(state, bytenr, processed_len,
2163 &block_ctx, 0);
2164 if (ret) {
2165 printk(KERN_INFO
2166 "btrfsic: btrfsic_map_block(root @%llu)"
2167 " failed!\n",
2168 dev_bytenr);
2169 goto continue_loop;
2170 }
2171 }
2172 block_ctx.datav = mapped_datav;
2173 /* the following is required in case of writes to mirrors,
2174 * use the same that was used for the lookup */
2175 block_ctx.dev = dev_state;
2176 block_ctx.dev_bytenr = dev_bytenr;
2177
2178 block = btrfsic_block_alloc();
2179 if (NULL == block) {
2180 printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
2181 btrfsic_release_block_ctx(&block_ctx);
2182 goto continue_loop;
2183 }
2184 block->dev_state = dev_state;
2185 block->dev_bytenr = dev_bytenr;
2186 block->logical_bytenr = bytenr;
2187 block->is_metadata = is_metadata;
2188 block->never_written = 0;
2189 block->iodone_w_error = 0;
2190 block->mirror_num = 0; /* unknown */
2191 block->flush_gen = dev_state->last_flush_gen + 1;
2192 block->submit_bio_bh_rw = submit_bio_bh_rw;
2193 if (NULL != bio) {
2194 block->is_iodone = 0;
2195 BUG_ON(NULL == bio_is_patched);
2196 if (!*bio_is_patched) {
2197 block->orig_bio_bh_private = bio->bi_private;
2198 block->orig_bio_bh_end_io.bio = bio->bi_end_io;
2199 block->next_in_same_bio = NULL;
2200 bio->bi_private = block;
2201 bio->bi_end_io = btrfsic_bio_end_io;
2202 *bio_is_patched = 1;
2203 } else {
2204 struct btrfsic_block *chained_block =
2205 (struct btrfsic_block *)
2206 bio->bi_private;
2207
2208 BUG_ON(NULL == chained_block);
2209 block->orig_bio_bh_private =
2210 chained_block->orig_bio_bh_private;
2211 block->orig_bio_bh_end_io.bio =
2212 chained_block->orig_bio_bh_end_io.bio;
2213 block->next_in_same_bio = chained_block;
2214 bio->bi_private = block;
2215 }
2216 } else if (NULL != bh) {
2217 block->is_iodone = 0;
2218 block->orig_bio_bh_private = bh->b_private;
2219 block->orig_bio_bh_end_io.bh = bh->b_end_io;
2220 block->next_in_same_bio = NULL;
2221 bh->b_private = block;
2222 bh->b_end_io = btrfsic_bh_end_io;
2223 } else {
2224 block->is_iodone = 1;
2225 block->orig_bio_bh_private = NULL;
2226 block->orig_bio_bh_end_io.bio = NULL;
2227 block->next_in_same_bio = NULL;
2228 }
2229 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2230 printk(KERN_INFO
2231 "New written %c-block @%llu (%s/%llu/%d)\n",
2232 is_metadata ? 'M' : 'D',
2233 block->logical_bytenr, block->dev_state->name,
2234 block->dev_bytenr, block->mirror_num);
2235 list_add(&block->all_blocks_node, &state->all_blocks_list);
2236 btrfsic_block_hashtable_add(block, &state->block_hashtable);
2237
2238 if (is_metadata) {
2239 ret = btrfsic_process_metablock(state, block,
2240 &block_ctx, 0, 0);
2241 if (ret)
2242 printk(KERN_INFO
2243 "btrfsic: process_metablock(root @%llu)"
2244 " failed!\n",
2245 dev_bytenr);
2246 }
2247 btrfsic_release_block_ctx(&block_ctx);
2248 }
2249
2250 continue_loop:
2251 BUG_ON(!processed_len);
2252 dev_bytenr += processed_len;
2253 mapped_datav += processed_len >> PAGE_CACHE_SHIFT;
2254 num_pages -= processed_len >> PAGE_CACHE_SHIFT;
2255 goto again;
2256 }
2257
2258 static void btrfsic_bio_end_io(struct bio *bp, int bio_error_status)
2259 {
2260 struct btrfsic_block *block = (struct btrfsic_block *)bp->bi_private;
2261 int iodone_w_error;
2262
2263 /* mutex is not held! This is not save if IO is not yet completed
2264 * on umount */
2265 iodone_w_error = 0;
2266 if (bio_error_status)
2267 iodone_w_error = 1;
2268
2269 BUG_ON(NULL == block);
2270 bp->bi_private = block->orig_bio_bh_private;
2271 bp->bi_end_io = block->orig_bio_bh_end_io.bio;
2272
2273 do {
2274 struct btrfsic_block *next_block;
2275 struct btrfsic_dev_state *const dev_state = block->dev_state;
2276
2277 if ((dev_state->state->print_mask &
2278 BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
2279 printk(KERN_INFO
2280 "bio_end_io(err=%d) for %c @%llu (%s/%llu/%d)\n",
2281 bio_error_status,
2282 btrfsic_get_block_type(dev_state->state, block),
2283 block->logical_bytenr, dev_state->name,
2284 block->dev_bytenr, block->mirror_num);
2285 next_block = block->next_in_same_bio;
2286 block->iodone_w_error = iodone_w_error;
2287 if (block->submit_bio_bh_rw & REQ_FLUSH) {
2288 dev_state->last_flush_gen++;
2289 if ((dev_state->state->print_mask &
2290 BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
2291 printk(KERN_INFO
2292 "bio_end_io() new %s flush_gen=%llu\n",
2293 dev_state->name,
2294 dev_state->last_flush_gen);
2295 }
2296 if (block->submit_bio_bh_rw & REQ_FUA)
2297 block->flush_gen = 0; /* FUA completed means block is
2298 * on disk */
2299 block->is_iodone = 1; /* for FLUSH, this releases the block */
2300 block = next_block;
2301 } while (NULL != block);
2302
2303 bp->bi_end_io(bp, bio_error_status);
2304 }
2305
2306 static void btrfsic_bh_end_io(struct buffer_head *bh, int uptodate)
2307 {
2308 struct btrfsic_block *block = (struct btrfsic_block *)bh->b_private;
2309 int iodone_w_error = !uptodate;
2310 struct btrfsic_dev_state *dev_state;
2311
2312 BUG_ON(NULL == block);
2313 dev_state = block->dev_state;
2314 if ((dev_state->state->print_mask & BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
2315 printk(KERN_INFO
2316 "bh_end_io(error=%d) for %c @%llu (%s/%llu/%d)\n",
2317 iodone_w_error,
2318 btrfsic_get_block_type(dev_state->state, block),
2319 block->logical_bytenr, block->dev_state->name,
2320 block->dev_bytenr, block->mirror_num);
2321
2322 block->iodone_w_error = iodone_w_error;
2323 if (block->submit_bio_bh_rw & REQ_FLUSH) {
2324 dev_state->last_flush_gen++;
2325 if ((dev_state->state->print_mask &
2326 BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
2327 printk(KERN_INFO
2328 "bh_end_io() new %s flush_gen=%llu\n",
2329 dev_state->name, dev_state->last_flush_gen);
2330 }
2331 if (block->submit_bio_bh_rw & REQ_FUA)
2332 block->flush_gen = 0; /* FUA completed means block is on disk */
2333
2334 bh->b_private = block->orig_bio_bh_private;
2335 bh->b_end_io = block->orig_bio_bh_end_io.bh;
2336 block->is_iodone = 1; /* for FLUSH, this releases the block */
2337 bh->b_end_io(bh, uptodate);
2338 }
2339
2340 static int btrfsic_process_written_superblock(
2341 struct btrfsic_state *state,
2342 struct btrfsic_block *const superblock,
2343 struct btrfs_super_block *const super_hdr)
2344 {
2345 int pass;
2346
2347 superblock->generation = btrfs_super_generation(super_hdr);
2348 if (!(superblock->generation > state->max_superblock_generation ||
2349 0 == state->max_superblock_generation)) {
2350 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
2351 printk(KERN_INFO
2352 "btrfsic: superblock @%llu (%s/%llu/%d)"
2353 " with old 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 } else {
2360 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
2361 printk(KERN_INFO
2362 "btrfsic: got new superblock @%llu (%s/%llu/%d)"
2363 " with new gen %llu > %llu\n",
2364 superblock->logical_bytenr,
2365 superblock->dev_state->name,
2366 superblock->dev_bytenr, superblock->mirror_num,
2367 btrfs_super_generation(super_hdr),
2368 state->max_superblock_generation);
2369
2370 state->max_superblock_generation =
2371 btrfs_super_generation(super_hdr);
2372 state->latest_superblock = superblock;
2373 }
2374
2375 for (pass = 0; pass < 3; pass++) {
2376 int ret;
2377 u64 next_bytenr;
2378 struct btrfsic_block *next_block;
2379 struct btrfsic_block_data_ctx tmp_next_block_ctx;
2380 struct btrfsic_block_link *l;
2381 int num_copies;
2382 int mirror_num;
2383 const char *additional_string = NULL;
2384 struct btrfs_disk_key tmp_disk_key = {0};
2385
2386 btrfs_set_disk_key_objectid(&tmp_disk_key,
2387 BTRFS_ROOT_ITEM_KEY);
2388 btrfs_set_disk_key_objectid(&tmp_disk_key, 0);
2389
2390 switch (pass) {
2391 case 0:
2392 btrfs_set_disk_key_objectid(&tmp_disk_key,
2393 BTRFS_ROOT_TREE_OBJECTID);
2394 additional_string = "root ";
2395 next_bytenr = btrfs_super_root(super_hdr);
2396 if (state->print_mask &
2397 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
2398 printk(KERN_INFO "root@%llu\n", next_bytenr);
2399 break;
2400 case 1:
2401 btrfs_set_disk_key_objectid(&tmp_disk_key,
2402 BTRFS_CHUNK_TREE_OBJECTID);
2403 additional_string = "chunk ";
2404 next_bytenr = btrfs_super_chunk_root(super_hdr);
2405 if (state->print_mask &
2406 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
2407 printk(KERN_INFO "chunk@%llu\n", next_bytenr);
2408 break;
2409 case 2:
2410 btrfs_set_disk_key_objectid(&tmp_disk_key,
2411 BTRFS_TREE_LOG_OBJECTID);
2412 additional_string = "log ";
2413 next_bytenr = btrfs_super_log_root(super_hdr);
2414 if (0 == next_bytenr)
2415 continue;
2416 if (state->print_mask &
2417 BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
2418 printk(KERN_INFO "log@%llu\n", next_bytenr);
2419 break;
2420 }
2421
2422 num_copies =
2423 btrfs_num_copies(state->root->fs_info,
2424 next_bytenr, BTRFS_SUPER_INFO_SIZE);
2425 if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
2426 printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
2427 next_bytenr, num_copies);
2428 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
2429 int was_created;
2430
2431 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2432 printk(KERN_INFO
2433 "btrfsic_process_written_superblock("
2434 "mirror_num=%d)\n", mirror_num);
2435 ret = btrfsic_map_block(state, next_bytenr,
2436 BTRFS_SUPER_INFO_SIZE,
2437 &tmp_next_block_ctx,
2438 mirror_num);
2439 if (ret) {
2440 printk(KERN_INFO
2441 "btrfsic: btrfsic_map_block(@%llu,"
2442 " mirror=%d) failed!\n",
2443 next_bytenr, mirror_num);
2444 return -1;
2445 }
2446
2447 next_block = btrfsic_block_lookup_or_add(
2448 state,
2449 &tmp_next_block_ctx,
2450 additional_string,
2451 1, 0, 1,
2452 mirror_num,
2453 &was_created);
2454 if (NULL == next_block) {
2455 printk(KERN_INFO
2456 "btrfsic: error, kmalloc failed!\n");
2457 btrfsic_release_block_ctx(&tmp_next_block_ctx);
2458 return -1;
2459 }
2460
2461 next_block->disk_key = tmp_disk_key;
2462 if (was_created)
2463 next_block->generation =
2464 BTRFSIC_GENERATION_UNKNOWN;
2465 l = btrfsic_block_link_lookup_or_add(
2466 state,
2467 &tmp_next_block_ctx,
2468 next_block,
2469 superblock,
2470 BTRFSIC_GENERATION_UNKNOWN);
2471 btrfsic_release_block_ctx(&tmp_next_block_ctx);
2472 if (NULL == l)
2473 return -1;
2474 }
2475 }
2476
2477 if (WARN_ON(-1 == btrfsic_check_all_ref_blocks(state, superblock, 0)))
2478 btrfsic_dump_tree(state);
2479
2480 return 0;
2481 }
2482
2483 static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state,
2484 struct btrfsic_block *const block,
2485 int recursion_level)
2486 {
2487 struct list_head *elem_ref_to;
2488 int ret = 0;
2489
2490 if (recursion_level >= 3 + BTRFS_MAX_LEVEL) {
2491 /*
2492 * Note that this situation can happen and does not
2493 * indicate an error in regular cases. It happens
2494 * when disk blocks are freed and later reused.
2495 * The check-integrity module is not aware of any
2496 * block free operations, it just recognizes block
2497 * write operations. Therefore it keeps the linkage
2498 * information for a block until a block is
2499 * rewritten. This can temporarily cause incorrect
2500 * and even circular linkage informations. This
2501 * causes no harm unless such blocks are referenced
2502 * by the most recent super block.
2503 */
2504 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2505 printk(KERN_INFO
2506 "btrfsic: abort cyclic linkage (case 1).\n");
2507
2508 return ret;
2509 }
2510
2511 /*
2512 * This algorithm is recursive because the amount of used stack
2513 * space is very small and the max recursion depth is limited.
2514 */
2515 list_for_each(elem_ref_to, &block->ref_to_list) {
2516 const struct btrfsic_block_link *const l =
2517 list_entry(elem_ref_to, struct btrfsic_block_link,
2518 node_ref_to);
2519
2520 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2521 printk(KERN_INFO
2522 "rl=%d, %c @%llu (%s/%llu/%d)"
2523 " %u* refers to %c @%llu (%s/%llu/%d)\n",
2524 recursion_level,
2525 btrfsic_get_block_type(state, block),
2526 block->logical_bytenr, block->dev_state->name,
2527 block->dev_bytenr, block->mirror_num,
2528 l->ref_cnt,
2529 btrfsic_get_block_type(state, l->block_ref_to),
2530 l->block_ref_to->logical_bytenr,
2531 l->block_ref_to->dev_state->name,
2532 l->block_ref_to->dev_bytenr,
2533 l->block_ref_to->mirror_num);
2534 if (l->block_ref_to->never_written) {
2535 printk(KERN_INFO "btrfs: attempt to write superblock"
2536 " which references block %c @%llu (%s/%llu/%d)"
2537 " which is never written!\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->is_iodone) {
2545 printk(KERN_INFO "btrfs: attempt to write superblock"
2546 " which references block %c @%llu (%s/%llu/%d)"
2547 " which is not yet iodone!\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->block_ref_to->iodone_w_error) {
2555 printk(KERN_INFO "btrfs: attempt to write superblock"
2556 " which references block %c @%llu (%s/%llu/%d)"
2557 " which has write error!\n",
2558 btrfsic_get_block_type(state, l->block_ref_to),
2559 l->block_ref_to->logical_bytenr,
2560 l->block_ref_to->dev_state->name,
2561 l->block_ref_to->dev_bytenr,
2562 l->block_ref_to->mirror_num);
2563 ret = -1;
2564 } else if (l->parent_generation !=
2565 l->block_ref_to->generation &&
2566 BTRFSIC_GENERATION_UNKNOWN !=
2567 l->parent_generation &&
2568 BTRFSIC_GENERATION_UNKNOWN !=
2569 l->block_ref_to->generation) {
2570 printk(KERN_INFO "btrfs: attempt to write superblock"
2571 " which references block %c @%llu (%s/%llu/%d)"
2572 " with generation %llu !="
2573 " parent generation %llu!\n",
2574 btrfsic_get_block_type(state, l->block_ref_to),
2575 l->block_ref_to->logical_bytenr,
2576 l->block_ref_to->dev_state->name,
2577 l->block_ref_to->dev_bytenr,
2578 l->block_ref_to->mirror_num,
2579 l->block_ref_to->generation,
2580 l->parent_generation);
2581 ret = -1;
2582 } else if (l->block_ref_to->flush_gen >
2583 l->block_ref_to->dev_state->last_flush_gen) {
2584 printk(KERN_INFO "btrfs: attempt to write superblock"
2585 " which references block %c @%llu (%s/%llu/%d)"
2586 " which is not flushed out of disk's write cache"
2587 " (block flush_gen=%llu,"
2588 " dev->flush_gen=%llu)!\n",
2589 btrfsic_get_block_type(state, l->block_ref_to),
2590 l->block_ref_to->logical_bytenr,
2591 l->block_ref_to->dev_state->name,
2592 l->block_ref_to->dev_bytenr,
2593 l->block_ref_to->mirror_num, block->flush_gen,
2594 l->block_ref_to->dev_state->last_flush_gen);
2595 ret = -1;
2596 } else if (-1 == btrfsic_check_all_ref_blocks(state,
2597 l->block_ref_to,
2598 recursion_level +
2599 1)) {
2600 ret = -1;
2601 }
2602 }
2603
2604 return ret;
2605 }
2606
2607 static int btrfsic_is_block_ref_by_superblock(
2608 const struct btrfsic_state *state,
2609 const struct btrfsic_block *block,
2610 int recursion_level)
2611 {
2612 struct list_head *elem_ref_from;
2613
2614 if (recursion_level >= 3 + BTRFS_MAX_LEVEL) {
2615 /* refer to comment at "abort cyclic linkage (case 1)" */
2616 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2617 printk(KERN_INFO
2618 "btrfsic: abort cyclic linkage (case 2).\n");
2619
2620 return 0;
2621 }
2622
2623 /*
2624 * This algorithm is recursive because the amount of used stack space
2625 * is very small and the max recursion depth is limited.
2626 */
2627 list_for_each(elem_ref_from, &block->ref_from_list) {
2628 const struct btrfsic_block_link *const l =
2629 list_entry(elem_ref_from, struct btrfsic_block_link,
2630 node_ref_from);
2631
2632 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2633 printk(KERN_INFO
2634 "rl=%d, %c @%llu (%s/%llu/%d)"
2635 " is ref %u* from %c @%llu (%s/%llu/%d)\n",
2636 recursion_level,
2637 btrfsic_get_block_type(state, block),
2638 block->logical_bytenr, block->dev_state->name,
2639 block->dev_bytenr, block->mirror_num,
2640 l->ref_cnt,
2641 btrfsic_get_block_type(state, l->block_ref_from),
2642 l->block_ref_from->logical_bytenr,
2643 l->block_ref_from->dev_state->name,
2644 l->block_ref_from->dev_bytenr,
2645 l->block_ref_from->mirror_num);
2646 if (l->block_ref_from->is_superblock &&
2647 state->latest_superblock->dev_bytenr ==
2648 l->block_ref_from->dev_bytenr &&
2649 state->latest_superblock->dev_state->bdev ==
2650 l->block_ref_from->dev_state->bdev)
2651 return 1;
2652 else if (btrfsic_is_block_ref_by_superblock(state,
2653 l->block_ref_from,
2654 recursion_level +
2655 1))
2656 return 1;
2657 }
2658
2659 return 0;
2660 }
2661
2662 static void btrfsic_print_add_link(const struct btrfsic_state *state,
2663 const struct btrfsic_block_link *l)
2664 {
2665 printk(KERN_INFO
2666 "Add %u* link from %c @%llu (%s/%llu/%d)"
2667 " to %c @%llu (%s/%llu/%d).\n",
2668 l->ref_cnt,
2669 btrfsic_get_block_type(state, l->block_ref_from),
2670 l->block_ref_from->logical_bytenr,
2671 l->block_ref_from->dev_state->name,
2672 l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num,
2673 btrfsic_get_block_type(state, l->block_ref_to),
2674 l->block_ref_to->logical_bytenr,
2675 l->block_ref_to->dev_state->name, l->block_ref_to->dev_bytenr,
2676 l->block_ref_to->mirror_num);
2677 }
2678
2679 static void btrfsic_print_rem_link(const struct btrfsic_state *state,
2680 const struct btrfsic_block_link *l)
2681 {
2682 printk(KERN_INFO
2683 "Rem %u* link from %c @%llu (%s/%llu/%d)"
2684 " to %c @%llu (%s/%llu/%d).\n",
2685 l->ref_cnt,
2686 btrfsic_get_block_type(state, l->block_ref_from),
2687 l->block_ref_from->logical_bytenr,
2688 l->block_ref_from->dev_state->name,
2689 l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num,
2690 btrfsic_get_block_type(state, l->block_ref_to),
2691 l->block_ref_to->logical_bytenr,
2692 l->block_ref_to->dev_state->name, l->block_ref_to->dev_bytenr,
2693 l->block_ref_to->mirror_num);
2694 }
2695
2696 static char btrfsic_get_block_type(const struct btrfsic_state *state,
2697 const struct btrfsic_block *block)
2698 {
2699 if (block->is_superblock &&
2700 state->latest_superblock->dev_bytenr == block->dev_bytenr &&
2701 state->latest_superblock->dev_state->bdev == block->dev_state->bdev)
2702 return 'S';
2703 else if (block->is_superblock)
2704 return 's';
2705 else if (block->is_metadata)
2706 return 'M';
2707 else
2708 return 'D';
2709 }
2710
2711 static void btrfsic_dump_tree(const struct btrfsic_state *state)
2712 {
2713 btrfsic_dump_tree_sub(state, state->latest_superblock, 0);
2714 }
2715
2716 static void btrfsic_dump_tree_sub(const struct btrfsic_state *state,
2717 const struct btrfsic_block *block,
2718 int indent_level)
2719 {
2720 struct list_head *elem_ref_to;
2721 int indent_add;
2722 static char buf[80];
2723 int cursor_position;
2724
2725 /*
2726 * Should better fill an on-stack buffer with a complete line and
2727 * dump it at once when it is time to print a newline character.
2728 */
2729
2730 /*
2731 * This algorithm is recursive because the amount of used stack space
2732 * is very small and the max recursion depth is limited.
2733 */
2734 indent_add = sprintf(buf, "%c-%llu(%s/%llu/%d)",
2735 btrfsic_get_block_type(state, block),
2736 block->logical_bytenr, block->dev_state->name,
2737 block->dev_bytenr, block->mirror_num);
2738 if (indent_level + indent_add > BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) {
2739 printk("[...]\n");
2740 return;
2741 }
2742 printk(buf);
2743 indent_level += indent_add;
2744 if (list_empty(&block->ref_to_list)) {
2745 printk("\n");
2746 return;
2747 }
2748 if (block->mirror_num > 1 &&
2749 !(state->print_mask & BTRFSIC_PRINT_MASK_TREE_WITH_ALL_MIRRORS)) {
2750 printk(" [...]\n");
2751 return;
2752 }
2753
2754 cursor_position = indent_level;
2755 list_for_each(elem_ref_to, &block->ref_to_list) {
2756 const struct btrfsic_block_link *const l =
2757 list_entry(elem_ref_to, struct btrfsic_block_link,
2758 node_ref_to);
2759
2760 while (cursor_position < indent_level) {
2761 printk(" ");
2762 cursor_position++;
2763 }
2764 if (l->ref_cnt > 1)
2765 indent_add = sprintf(buf, " %d*--> ", l->ref_cnt);
2766 else
2767 indent_add = sprintf(buf, " --> ");
2768 if (indent_level + indent_add >
2769 BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) {
2770 printk("[...]\n");
2771 cursor_position = 0;
2772 continue;
2773 }
2774
2775 printk(buf);
2776
2777 btrfsic_dump_tree_sub(state, l->block_ref_to,
2778 indent_level + indent_add);
2779 cursor_position = 0;
2780 }
2781 }
2782
2783 static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add(
2784 struct btrfsic_state *state,
2785 struct btrfsic_block_data_ctx *next_block_ctx,
2786 struct btrfsic_block *next_block,
2787 struct btrfsic_block *from_block,
2788 u64 parent_generation)
2789 {
2790 struct btrfsic_block_link *l;
2791
2792 l = btrfsic_block_link_hashtable_lookup(next_block_ctx->dev->bdev,
2793 next_block_ctx->dev_bytenr,
2794 from_block->dev_state->bdev,
2795 from_block->dev_bytenr,
2796 &state->block_link_hashtable);
2797 if (NULL == l) {
2798 l = btrfsic_block_link_alloc();
2799 if (NULL == l) {
2800 printk(KERN_INFO
2801 "btrfsic: error, kmalloc" " failed!\n");
2802 return NULL;
2803 }
2804
2805 l->block_ref_to = next_block;
2806 l->block_ref_from = from_block;
2807 l->ref_cnt = 1;
2808 l->parent_generation = parent_generation;
2809
2810 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2811 btrfsic_print_add_link(state, l);
2812
2813 list_add(&l->node_ref_to, &from_block->ref_to_list);
2814 list_add(&l->node_ref_from, &next_block->ref_from_list);
2815
2816 btrfsic_block_link_hashtable_add(l,
2817 &state->block_link_hashtable);
2818 } else {
2819 l->ref_cnt++;
2820 l->parent_generation = parent_generation;
2821 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2822 btrfsic_print_add_link(state, l);
2823 }
2824
2825 return l;
2826 }
2827
2828 static struct btrfsic_block *btrfsic_block_lookup_or_add(
2829 struct btrfsic_state *state,
2830 struct btrfsic_block_data_ctx *block_ctx,
2831 const char *additional_string,
2832 int is_metadata,
2833 int is_iodone,
2834 int never_written,
2835 int mirror_num,
2836 int *was_created)
2837 {
2838 struct btrfsic_block *block;
2839
2840 block = btrfsic_block_hashtable_lookup(block_ctx->dev->bdev,
2841 block_ctx->dev_bytenr,
2842 &state->block_hashtable);
2843 if (NULL == block) {
2844 struct btrfsic_dev_state *dev_state;
2845
2846 block = btrfsic_block_alloc();
2847 if (NULL == block) {
2848 printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
2849 return NULL;
2850 }
2851 dev_state = btrfsic_dev_state_lookup(block_ctx->dev->bdev);
2852 if (NULL == dev_state) {
2853 printk(KERN_INFO
2854 "btrfsic: error, lookup dev_state failed!\n");
2855 btrfsic_block_free(block);
2856 return NULL;
2857 }
2858 block->dev_state = dev_state;
2859 block->dev_bytenr = block_ctx->dev_bytenr;
2860 block->logical_bytenr = block_ctx->start;
2861 block->is_metadata = is_metadata;
2862 block->is_iodone = is_iodone;
2863 block->never_written = never_written;
2864 block->mirror_num = mirror_num;
2865 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
2866 printk(KERN_INFO
2867 "New %s%c-block @%llu (%s/%llu/%d)\n",
2868 additional_string,
2869 btrfsic_get_block_type(state, block),
2870 block->logical_bytenr, dev_state->name,
2871 block->dev_bytenr, mirror_num);
2872 list_add(&block->all_blocks_node, &state->all_blocks_list);
2873 btrfsic_block_hashtable_add(block, &state->block_hashtable);
2874 if (NULL != was_created)
2875 *was_created = 1;
2876 } else {
2877 if (NULL != was_created)
2878 *was_created = 0;
2879 }
2880
2881 return block;
2882 }
2883
2884 static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state,
2885 u64 bytenr,
2886 struct btrfsic_dev_state *dev_state,
2887 u64 dev_bytenr)
2888 {
2889 int num_copies;
2890 int mirror_num;
2891 int ret;
2892 struct btrfsic_block_data_ctx block_ctx;
2893 int match = 0;
2894
2895 num_copies = btrfs_num_copies(state->root->fs_info,
2896 bytenr, state->metablock_size);
2897
2898 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
2899 ret = btrfsic_map_block(state, bytenr, state->metablock_size,
2900 &block_ctx, mirror_num);
2901 if (ret) {
2902 printk(KERN_INFO "btrfsic:"
2903 " btrfsic_map_block(logical @%llu,"
2904 " mirror %d) failed!\n",
2905 bytenr, mirror_num);
2906 continue;
2907 }
2908
2909 if (dev_state->bdev == block_ctx.dev->bdev &&
2910 dev_bytenr == block_ctx.dev_bytenr) {
2911 match++;
2912 btrfsic_release_block_ctx(&block_ctx);
2913 break;
2914 }
2915 btrfsic_release_block_ctx(&block_ctx);
2916 }
2917
2918 if (WARN_ON(!match)) {
2919 printk(KERN_INFO "btrfs: attempt to write M-block which contains logical bytenr that doesn't map to dev+physical bytenr of submit_bio,"
2920 " buffer->log_bytenr=%llu, submit_bio(bdev=%s,"
2921 " phys_bytenr=%llu)!\n",
2922 bytenr, dev_state->name, dev_bytenr);
2923 for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
2924 ret = btrfsic_map_block(state, bytenr,
2925 state->metablock_size,
2926 &block_ctx, mirror_num);
2927 if (ret)
2928 continue;
2929
2930 printk(KERN_INFO "Read logical bytenr @%llu maps to"
2931 " (%s/%llu/%d)\n",
2932 bytenr, block_ctx.dev->name,
2933 block_ctx.dev_bytenr, mirror_num);
2934 }
2935 }
2936 }
2937
2938 static struct btrfsic_dev_state *btrfsic_dev_state_lookup(
2939 struct block_device *bdev)
2940 {
2941 struct btrfsic_dev_state *ds;
2942
2943 ds = btrfsic_dev_state_hashtable_lookup(bdev,
2944 &btrfsic_dev_state_hashtable);
2945 return ds;
2946 }
2947
2948 int btrfsic_submit_bh(int rw, struct buffer_head *bh)
2949 {
2950 struct btrfsic_dev_state *dev_state;
2951
2952 if (!btrfsic_is_initialized)
2953 return submit_bh(rw, bh);
2954
2955 mutex_lock(&btrfsic_mutex);
2956 /* since btrfsic_submit_bh() might also be called before
2957 * btrfsic_mount(), this might return NULL */
2958 dev_state = btrfsic_dev_state_lookup(bh->b_bdev);
2959
2960 /* Only called to write the superblock (incl. FLUSH/FUA) */
2961 if (NULL != dev_state &&
2962 (rw & WRITE) && bh->b_size > 0) {
2963 u64 dev_bytenr;
2964
2965 dev_bytenr = 4096 * bh->b_blocknr;
2966 if (dev_state->state->print_mask &
2967 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
2968 printk(KERN_INFO
2969 "submit_bh(rw=0x%x, blocknr=%llu (bytenr %llu),"
2970 " size=%zu, data=%p, bdev=%p)\n",
2971 rw, (unsigned long long)bh->b_blocknr,
2972 dev_bytenr, bh->b_size, bh->b_data, bh->b_bdev);
2973 btrfsic_process_written_block(dev_state, dev_bytenr,
2974 &bh->b_data, 1, NULL,
2975 NULL, bh, rw);
2976 } else if (NULL != dev_state && (rw & REQ_FLUSH)) {
2977 if (dev_state->state->print_mask &
2978 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
2979 printk(KERN_INFO
2980 "submit_bh(rw=0x%x FLUSH, bdev=%p)\n",
2981 rw, bh->b_bdev);
2982 if (!dev_state->dummy_block_for_bio_bh_flush.is_iodone) {
2983 if ((dev_state->state->print_mask &
2984 (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH |
2985 BTRFSIC_PRINT_MASK_VERBOSE)))
2986 printk(KERN_INFO
2987 "btrfsic_submit_bh(%s) with FLUSH"
2988 " but dummy block already in use"
2989 " (ignored)!\n",
2990 dev_state->name);
2991 } else {
2992 struct btrfsic_block *const block =
2993 &dev_state->dummy_block_for_bio_bh_flush;
2994
2995 block->is_iodone = 0;
2996 block->never_written = 0;
2997 block->iodone_w_error = 0;
2998 block->flush_gen = dev_state->last_flush_gen + 1;
2999 block->submit_bio_bh_rw = rw;
3000 block->orig_bio_bh_private = bh->b_private;
3001 block->orig_bio_bh_end_io.bh = bh->b_end_io;
3002 block->next_in_same_bio = NULL;
3003 bh->b_private = block;
3004 bh->b_end_io = btrfsic_bh_end_io;
3005 }
3006 }
3007 mutex_unlock(&btrfsic_mutex);
3008 return submit_bh(rw, bh);
3009 }
3010
3011 void btrfsic_submit_bio(int rw, struct bio *bio)
3012 {
3013 struct btrfsic_dev_state *dev_state;
3014
3015 if (!btrfsic_is_initialized) {
3016 submit_bio(rw, bio);
3017 return;
3018 }
3019
3020 mutex_lock(&btrfsic_mutex);
3021 /* since btrfsic_submit_bio() is also called before
3022 * btrfsic_mount(), this might return NULL */
3023 dev_state = btrfsic_dev_state_lookup(bio->bi_bdev);
3024 if (NULL != dev_state &&
3025 (rw & WRITE) && NULL != bio->bi_io_vec) {
3026 unsigned int i;
3027 u64 dev_bytenr;
3028 u64 cur_bytenr;
3029 int bio_is_patched;
3030 char **mapped_datav;
3031
3032 dev_bytenr = 512 * bio->bi_sector;
3033 bio_is_patched = 0;
3034 if (dev_state->state->print_mask &
3035 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
3036 printk(KERN_INFO
3037 "submit_bio(rw=0x%x, bi_vcnt=%u,"
3038 " bi_sector=%llu (bytenr %llu), bi_bdev=%p)\n",
3039 rw, bio->bi_vcnt,
3040 (unsigned long long)bio->bi_sector, dev_bytenr,
3041 bio->bi_bdev);
3042
3043 mapped_datav = kmalloc(sizeof(*mapped_datav) * bio->bi_vcnt,
3044 GFP_NOFS);
3045 if (!mapped_datav)
3046 goto leave;
3047 cur_bytenr = dev_bytenr;
3048 for (i = 0; i < bio->bi_vcnt; i++) {
3049 BUG_ON(bio->bi_io_vec[i].bv_len != PAGE_CACHE_SIZE);
3050 mapped_datav[i] = kmap(bio->bi_io_vec[i].bv_page);
3051 if (!mapped_datav[i]) {
3052 while (i > 0) {
3053 i--;
3054 kunmap(bio->bi_io_vec[i].bv_page);
3055 }
3056 kfree(mapped_datav);
3057 goto leave;
3058 }
3059 if (dev_state->state->print_mask &
3060 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE)
3061 printk(KERN_INFO
3062 "#%u: bytenr=%llu, len=%u, offset=%u\n",
3063 i, cur_bytenr, bio->bi_io_vec[i].bv_len,
3064 bio->bi_io_vec[i].bv_offset);
3065 cur_bytenr += bio->bi_io_vec[i].bv_len;
3066 }
3067 btrfsic_process_written_block(dev_state, dev_bytenr,
3068 mapped_datav, bio->bi_vcnt,
3069 bio, &bio_is_patched,
3070 NULL, rw);
3071 while (i > 0) {
3072 i--;
3073 kunmap(bio->bi_io_vec[i].bv_page);
3074 }
3075 kfree(mapped_datav);
3076 } else if (NULL != dev_state && (rw & REQ_FLUSH)) {
3077 if (dev_state->state->print_mask &
3078 BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
3079 printk(KERN_INFO
3080 "submit_bio(rw=0x%x FLUSH, bdev=%p)\n",
3081 rw, bio->bi_bdev);
3082 if (!dev_state->dummy_block_for_bio_bh_flush.is_iodone) {
3083 if ((dev_state->state->print_mask &
3084 (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH |
3085 BTRFSIC_PRINT_MASK_VERBOSE)))
3086 printk(KERN_INFO
3087 "btrfsic_submit_bio(%s) with FLUSH"
3088 " but dummy block already in use"
3089 " (ignored)!\n",
3090 dev_state->name);
3091 } else {
3092 struct btrfsic_block *const block =
3093 &dev_state->dummy_block_for_bio_bh_flush;
3094
3095 block->is_iodone = 0;
3096 block->never_written = 0;
3097 block->iodone_w_error = 0;
3098 block->flush_gen = dev_state->last_flush_gen + 1;
3099 block->submit_bio_bh_rw = rw;
3100 block->orig_bio_bh_private = bio->bi_private;
3101 block->orig_bio_bh_end_io.bio = bio->bi_end_io;
3102 block->next_in_same_bio = NULL;
3103 bio->bi_private = block;
3104 bio->bi_end_io = btrfsic_bio_end_io;
3105 }
3106 }
3107 leave:
3108 mutex_unlock(&btrfsic_mutex);
3109
3110 submit_bio(rw, bio);
3111 }
3112
3113 int btrfsic_mount(struct btrfs_root *root,
3114 struct btrfs_fs_devices *fs_devices,
3115 int including_extent_data, u32 print_mask)
3116 {
3117 int ret;
3118 struct btrfsic_state *state;
3119 struct list_head *dev_head = &fs_devices->devices;
3120 struct btrfs_device *device;
3121
3122 if (root->nodesize != root->leafsize) {
3123 printk(KERN_INFO
3124 "btrfsic: cannot handle nodesize %d != leafsize %d!\n",
3125 root->nodesize, root->leafsize);
3126 return -1;
3127 }
3128 if (root->nodesize & ((u64)PAGE_CACHE_SIZE - 1)) {
3129 printk(KERN_INFO
3130 "btrfsic: cannot handle nodesize %d not being a multiple of PAGE_CACHE_SIZE %ld!\n",
3131 root->nodesize, PAGE_CACHE_SIZE);
3132 return -1;
3133 }
3134 if (root->leafsize & ((u64)PAGE_CACHE_SIZE - 1)) {
3135 printk(KERN_INFO
3136 "btrfsic: cannot handle leafsize %d not being a multiple of PAGE_CACHE_SIZE %ld!\n",
3137 root->leafsize, PAGE_CACHE_SIZE);
3138 return -1;
3139 }
3140 if (root->sectorsize & ((u64)PAGE_CACHE_SIZE - 1)) {
3141 printk(KERN_INFO
3142 "btrfsic: cannot handle sectorsize %d not being a multiple of PAGE_CACHE_SIZE %ld!\n",
3143 root->sectorsize, PAGE_CACHE_SIZE);
3144 return -1;
3145 }
3146 state = kzalloc(sizeof(*state), GFP_NOFS);
3147 if (NULL == state) {
3148 printk(KERN_INFO "btrfs check-integrity: kmalloc() failed!\n");
3149 return -1;
3150 }
3151
3152 if (!btrfsic_is_initialized) {
3153 mutex_init(&btrfsic_mutex);
3154 btrfsic_dev_state_hashtable_init(&btrfsic_dev_state_hashtable);
3155 btrfsic_is_initialized = 1;
3156 }
3157 mutex_lock(&btrfsic_mutex);
3158 state->root = root;
3159 state->print_mask = print_mask;
3160 state->include_extent_data = including_extent_data;
3161 state->csum_size = 0;
3162 state->metablock_size = root->nodesize;
3163 state->datablock_size = root->sectorsize;
3164 INIT_LIST_HEAD(&state->all_blocks_list);
3165 btrfsic_block_hashtable_init(&state->block_hashtable);
3166 btrfsic_block_link_hashtable_init(&state->block_link_hashtable);
3167 state->max_superblock_generation = 0;
3168 state->latest_superblock = NULL;
3169
3170 list_for_each_entry(device, dev_head, dev_list) {
3171 struct btrfsic_dev_state *ds;
3172 char *p;
3173
3174 if (!device->bdev || !device->name)
3175 continue;
3176
3177 ds = btrfsic_dev_state_alloc();
3178 if (NULL == ds) {
3179 printk(KERN_INFO
3180 "btrfs check-integrity: kmalloc() failed!\n");
3181 mutex_unlock(&btrfsic_mutex);
3182 return -1;
3183 }
3184 ds->bdev = device->bdev;
3185 ds->state = state;
3186 bdevname(ds->bdev, ds->name);
3187 ds->name[BDEVNAME_SIZE - 1] = '\0';
3188 for (p = ds->name; *p != '\0'; p++);
3189 while (p > ds->name && *p != '/')
3190 p--;
3191 if (*p == '/')
3192 p++;
3193 strlcpy(ds->name, p, sizeof(ds->name));
3194 btrfsic_dev_state_hashtable_add(ds,
3195 &btrfsic_dev_state_hashtable);
3196 }
3197
3198 ret = btrfsic_process_superblock(state, fs_devices);
3199 if (0 != ret) {
3200 mutex_unlock(&btrfsic_mutex);
3201 btrfsic_unmount(root, fs_devices);
3202 return ret;
3203 }
3204
3205 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_DATABASE)
3206 btrfsic_dump_database(state);
3207 if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_TREE)
3208 btrfsic_dump_tree(state);
3209
3210 mutex_unlock(&btrfsic_mutex);
3211 return 0;
3212 }
3213
3214 void btrfsic_unmount(struct btrfs_root *root,
3215 struct btrfs_fs_devices *fs_devices)
3216 {
3217 struct list_head *elem_all;
3218 struct list_head *tmp_all;
3219 struct btrfsic_state *state;
3220 struct list_head *dev_head = &fs_devices->devices;
3221 struct btrfs_device *device;
3222
3223 if (!btrfsic_is_initialized)
3224 return;
3225
3226 mutex_lock(&btrfsic_mutex);
3227
3228 state = NULL;
3229 list_for_each_entry(device, dev_head, dev_list) {
3230 struct btrfsic_dev_state *ds;
3231
3232 if (!device->bdev || !device->name)
3233 continue;
3234
3235 ds = btrfsic_dev_state_hashtable_lookup(
3236 device->bdev,
3237 &btrfsic_dev_state_hashtable);
3238 if (NULL != ds) {
3239 state = ds->state;
3240 btrfsic_dev_state_hashtable_remove(ds);
3241 btrfsic_dev_state_free(ds);
3242 }
3243 }
3244
3245 if (NULL == state) {
3246 printk(KERN_INFO
3247 "btrfsic: error, cannot find state information"
3248 " on umount!\n");
3249 mutex_unlock(&btrfsic_mutex);
3250 return;
3251 }
3252
3253 /*
3254 * Don't care about keeping the lists' state up to date,
3255 * just free all memory that was allocated dynamically.
3256 * Free the blocks and the block_links.
3257 */
3258 list_for_each_safe(elem_all, tmp_all, &state->all_blocks_list) {
3259 struct btrfsic_block *const b_all =
3260 list_entry(elem_all, struct btrfsic_block,
3261 all_blocks_node);
3262 struct list_head *elem_ref_to;
3263 struct list_head *tmp_ref_to;
3264
3265 list_for_each_safe(elem_ref_to, tmp_ref_to,
3266 &b_all->ref_to_list) {
3267 struct btrfsic_block_link *const l =
3268 list_entry(elem_ref_to,
3269 struct btrfsic_block_link,
3270 node_ref_to);
3271
3272 if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
3273 btrfsic_print_rem_link(state, l);
3274
3275 l->ref_cnt--;
3276 if (0 == l->ref_cnt)
3277 btrfsic_block_link_free(l);
3278 }
3279
3280 if (b_all->is_iodone || b_all->never_written)
3281 btrfsic_block_free(b_all);
3282 else
3283 printk(KERN_INFO "btrfs: attempt to free %c-block"
3284 " @%llu (%s/%llu/%d) on umount which is"
3285 " not yet iodone!\n",
3286 btrfsic_get_block_type(state, b_all),
3287 b_all->logical_bytenr, b_all->dev_state->name,
3288 b_all->dev_bytenr, b_all->mirror_num);
3289 }
3290
3291 mutex_unlock(&btrfsic_mutex);
3292
3293 kfree(state);
3294 }
Linus' kernel tree