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authorStefan Behrens <sbehrens@giantdisaster.de>2011-11-01 17:04:16 +0100
committerStefan Behrens <sbehrens@giantdisaster.de>2011-12-21 19:14:09 +0100
commit5db0276014b80484689eb6c1bf7b94af1c7d5b1a (patch)
treeaff97316126b8230a8a9bf16f9e6904f6ed03e25 /fs/btrfs/check-integrity.c
parentd85c8a6f1bc083279215ff6e79b7c292bf3ec905 (diff)
Btrfs: add optional integrity check code
The two files added in this patch contain all the code that is required to implement the integrity checks. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Diffstat (limited to 'fs/btrfs/check-integrity.c')
-rw-r--r--fs/btrfs/check-integrity.c3068
1 files changed, 3068 insertions, 0 deletions
diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c
new file mode 100644
index 00000000000..ad0b3ba735b
--- /dev/null
+++ b/fs/btrfs/check-integrity.c
@@ -0,0 +1,3068 @@
+/*
+ * Copyright (C) STRATO AG 2011. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+/*
+ * This module can be used to catch cases when the btrfs kernel
+ * code executes write requests to the disk that bring the file
+ * system in an inconsistent state. In such a state, a power-loss
+ * or kernel panic event would cause that the data on disk is
+ * lost or at least damaged.
+ *
+ * Code is added that examines all block write requests during
+ * runtime (including writes of the super block). Three rules
+ * are verified and an error is printed on violation of the
+ * rules:
+ * 1. It is not allowed to write a disk block which is
+ * currently referenced by the super block (either directly
+ * or indirectly).
+ * 2. When a super block is written, it is verified that all
+ * referenced (directly or indirectly) blocks fulfill the
+ * following requirements:
+ * 2a. All referenced blocks have either been present when
+ * the file system was mounted, (i.e., they have been
+ * referenced by the super block) or they have been
+ * written since then and the write completion callback
+ * was called and a FLUSH request to the device where
+ * these blocks are located was received and completed.
+ * 2b. All referenced blocks need to have a generation
+ * number which is equal to the parent's number.
+ *
+ * One issue that was found using this module was that the log
+ * tree on disk became temporarily corrupted because disk blocks
+ * that had been in use for the log tree had been freed and
+ * reused too early, while being referenced by the written super
+ * block.
+ *
+ * The search term in the kernel log that can be used to filter
+ * on the existence of detected integrity issues is
+ * "btrfs: attempt".
+ *
+ * The integrity check is enabled via mount options. These
+ * mount options are only supported if the integrity check
+ * tool is compiled by defining BTRFS_FS_CHECK_INTEGRITY.
+ *
+ * Example #1, apply integrity checks to all metadata:
+ * mount /dev/sdb1 /mnt -o check_int
+ *
+ * Example #2, apply integrity checks to all metadata and
+ * to data extents:
+ * mount /dev/sdb1 /mnt -o check_int_data
+ *
+ * Example #3, apply integrity checks to all metadata and dump
+ * the tree that the super block references to kernel messages
+ * each time after a super block was written:
+ * mount /dev/sdb1 /mnt -o check_int,check_int_print_mask=263
+ *
+ * If the integrity check tool is included and activated in
+ * the mount options, plenty of kernel memory is used, and
+ * plenty of additional CPU cycles are spent. Enabling this
+ * functionality is not intended for normal use. In most
+ * cases, unless you are a btrfs developer who needs to verify
+ * the integrity of (super)-block write requests, do not
+ * enable the config option BTRFS_FS_CHECK_INTEGRITY to
+ * include and compile the integrity check tool.
+ */
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/buffer_head.h>
+#include <linux/mutex.h>
+#include <linux/crc32c.h>
+#include <linux/genhd.h>
+#include <linux/blkdev.h>
+#include "ctree.h"
+#include "disk-io.h"
+#include "transaction.h"
+#include "extent_io.h"
+#include "disk-io.h"
+#include "volumes.h"
+#include "print-tree.h"
+#include "locking.h"
+#include "check-integrity.h"
+
+#define BTRFSIC_BLOCK_HASHTABLE_SIZE 0x10000
+#define BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE 0x10000
+#define BTRFSIC_DEV2STATE_HASHTABLE_SIZE 0x100
+#define BTRFSIC_BLOCK_MAGIC_NUMBER 0x14491051
+#define BTRFSIC_BLOCK_LINK_MAGIC_NUMBER 0x11070807
+#define BTRFSIC_DEV2STATE_MAGIC_NUMBER 0x20111530
+#define BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER 20111300
+#define BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL (200 - 6) /* in characters,
+ * excluding " [...]" */
+#define BTRFSIC_BLOCK_SIZE PAGE_SIZE
+
+#define BTRFSIC_GENERATION_UNKNOWN ((u64)-1)
+
+/*
+ * The definition of the bitmask fields for the print_mask.
+ * They are specified with the mount option check_integrity_print_mask.
+ */
+#define BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE 0x00000001
+#define BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION 0x00000002
+#define BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE 0x00000004
+#define BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE 0x00000008
+#define BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH 0x00000010
+#define BTRFSIC_PRINT_MASK_END_IO_BIO_BH 0x00000020
+#define BTRFSIC_PRINT_MASK_VERBOSE 0x00000040
+#define BTRFSIC_PRINT_MASK_VERY_VERBOSE 0x00000080
+#define BTRFSIC_PRINT_MASK_INITIAL_TREE 0x00000100
+#define BTRFSIC_PRINT_MASK_INITIAL_ALL_TREES 0x00000200
+#define BTRFSIC_PRINT_MASK_INITIAL_DATABASE 0x00000400
+#define BTRFSIC_PRINT_MASK_NUM_COPIES 0x00000800
+#define BTRFSIC_PRINT_MASK_TREE_WITH_ALL_MIRRORS 0x00001000
+
+struct btrfsic_dev_state;
+struct btrfsic_state;
+
+struct btrfsic_block {
+ u32 magic_num; /* only used for debug purposes */
+ unsigned int is_metadata:1; /* if it is meta-data, not data-data */
+ unsigned int is_superblock:1; /* if it is one of the superblocks */
+ unsigned int is_iodone:1; /* if is done by lower subsystem */
+ unsigned int iodone_w_error:1; /* error was indicated to endio */
+ unsigned int never_written:1; /* block was added because it was
+ * referenced, not because it was
+ * written */
+ unsigned int mirror_num:2; /* large enough to hold
+ * BTRFS_SUPER_MIRROR_MAX */
+ struct btrfsic_dev_state *dev_state;
+ u64 dev_bytenr; /* key, physical byte num on disk */
+ u64 logical_bytenr; /* logical byte num on disk */
+ u64 generation;
+ struct btrfs_disk_key disk_key; /* extra info to print in case of
+ * issues, will not always be correct */
+ struct list_head collision_resolving_node; /* list node */
+ struct list_head all_blocks_node; /* list node */
+
+ /* the following two lists contain block_link items */
+ struct list_head ref_to_list; /* list */
+ struct list_head ref_from_list; /* list */
+ struct btrfsic_block *next_in_same_bio;
+ void *orig_bio_bh_private;
+ union {
+ bio_end_io_t *bio;
+ bh_end_io_t *bh;
+ } orig_bio_bh_end_io;
+ int submit_bio_bh_rw;
+ u64 flush_gen; /* only valid if !never_written */
+};
+
+/*
+ * Elements of this type are allocated dynamically and required because
+ * each block object can refer to and can be ref from multiple blocks.
+ * The key to lookup them in the hashtable is the dev_bytenr of
+ * the block ref to plus the one from the block refered from.
+ * The fact that they are searchable via a hashtable and that a
+ * ref_cnt is maintained is not required for the btrfs integrity
+ * check algorithm itself, it is only used to make the output more
+ * beautiful in case that an error is detected (an error is defined
+ * as a write operation to a block while that block is still referenced).
+ */
+struct btrfsic_block_link {
+ u32 magic_num; /* only used for debug purposes */
+ u32 ref_cnt;
+ struct list_head node_ref_to; /* list node */
+ struct list_head node_ref_from; /* list node */
+ struct list_head collision_resolving_node; /* list node */
+ struct btrfsic_block *block_ref_to;
+ struct btrfsic_block *block_ref_from;
+ u64 parent_generation;
+};
+
+struct btrfsic_dev_state {
+ u32 magic_num; /* only used for debug purposes */
+ struct block_device *bdev;
+ struct btrfsic_state *state;
+ struct list_head collision_resolving_node; /* list node */
+ struct btrfsic_block dummy_block_for_bio_bh_flush;
+ u64 last_flush_gen;
+ char name[BDEVNAME_SIZE];
+};
+
+struct btrfsic_block_hashtable {
+ struct list_head table[BTRFSIC_BLOCK_HASHTABLE_SIZE];
+};
+
+struct btrfsic_block_link_hashtable {
+ struct list_head table[BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE];
+};
+
+struct btrfsic_dev_state_hashtable {
+ struct list_head table[BTRFSIC_DEV2STATE_HASHTABLE_SIZE];
+};
+
+struct btrfsic_block_data_ctx {
+ u64 start; /* virtual bytenr */
+ u64 dev_bytenr; /* physical bytenr on device */
+ u32 len;
+ struct btrfsic_dev_state *dev;
+ char *data;
+ struct buffer_head *bh; /* do not use if set to NULL */
+};
+
+/* This structure is used to implement recursion without occupying
+ * any stack space, refer to btrfsic_process_metablock() */
+struct btrfsic_stack_frame {
+ u32 magic;
+ u32 nr;
+ int error;
+ int i;
+ int limit_nesting;
+ int num_copies;
+ int mirror_num;
+ struct btrfsic_block *block;
+ struct btrfsic_block_data_ctx *block_ctx;
+ struct btrfsic_block *next_block;
+ struct btrfsic_block_data_ctx next_block_ctx;
+ struct btrfs_header *hdr;
+ struct btrfsic_stack_frame *prev;
+};
+
+/* Some state per mounted filesystem */
+struct btrfsic_state {
+ u32 print_mask;
+ int include_extent_data;
+ int csum_size;
+ struct list_head all_blocks_list;
+ struct btrfsic_block_hashtable block_hashtable;
+ struct btrfsic_block_link_hashtable block_link_hashtable;
+ struct btrfs_root *root;
+ u64 max_superblock_generation;
+ struct btrfsic_block *latest_superblock;
+};
+
+static void btrfsic_block_init(struct btrfsic_block *b);
+static struct btrfsic_block *btrfsic_block_alloc(void);
+static void btrfsic_block_free(struct btrfsic_block *b);
+static void btrfsic_block_link_init(struct btrfsic_block_link *n);
+static struct btrfsic_block_link *btrfsic_block_link_alloc(void);
+static void btrfsic_block_link_free(struct btrfsic_block_link *n);
+static void btrfsic_dev_state_init(struct btrfsic_dev_state *ds);
+static struct btrfsic_dev_state *btrfsic_dev_state_alloc(void);
+static void btrfsic_dev_state_free(struct btrfsic_dev_state *ds);
+static void btrfsic_block_hashtable_init(struct btrfsic_block_hashtable *h);
+static void btrfsic_block_hashtable_add(struct btrfsic_block *b,
+ struct btrfsic_block_hashtable *h);
+static void btrfsic_block_hashtable_remove(struct btrfsic_block *b);
+static struct btrfsic_block *btrfsic_block_hashtable_lookup(
+ struct block_device *bdev,
+ u64 dev_bytenr,
+ struct btrfsic_block_hashtable *h);
+static void btrfsic_block_link_hashtable_init(
+ struct btrfsic_block_link_hashtable *h);
+static void btrfsic_block_link_hashtable_add(
+ struct btrfsic_block_link *l,
+ struct btrfsic_block_link_hashtable *h);
+static void btrfsic_block_link_hashtable_remove(struct btrfsic_block_link *l);
+static struct btrfsic_block_link *btrfsic_block_link_hashtable_lookup(
+ struct block_device *bdev_ref_to,
+ u64 dev_bytenr_ref_to,
+ struct block_device *bdev_ref_from,
+ u64 dev_bytenr_ref_from,
+ struct btrfsic_block_link_hashtable *h);
+static void btrfsic_dev_state_hashtable_init(
+ struct btrfsic_dev_state_hashtable *h);
+static void btrfsic_dev_state_hashtable_add(
+ struct btrfsic_dev_state *ds,
+ struct btrfsic_dev_state_hashtable *h);
+static void btrfsic_dev_state_hashtable_remove(struct btrfsic_dev_state *ds);
+static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(
+ struct block_device *bdev,
+ struct btrfsic_dev_state_hashtable *h);
+static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void);
+static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf);
+static int btrfsic_process_superblock(struct btrfsic_state *state,
+ struct btrfs_fs_devices *fs_devices);
+static int btrfsic_process_metablock(struct btrfsic_state *state,
+ struct btrfsic_block *block,
+ struct btrfsic_block_data_ctx *block_ctx,
+ struct btrfs_header *hdr,
+ int limit_nesting, int force_iodone_flag);
+static int btrfsic_create_link_to_next_block(
+ struct btrfsic_state *state,
+ struct btrfsic_block *block,
+ struct btrfsic_block_data_ctx
+ *block_ctx, u64 next_bytenr,
+ int limit_nesting,
+ struct btrfsic_block_data_ctx *next_block_ctx,
+ struct btrfsic_block **next_blockp,
+ int force_iodone_flag,
+ int *num_copiesp, int *mirror_nump,
+ struct btrfs_disk_key *disk_key,
+ u64 parent_generation);
+static int btrfsic_handle_extent_data(struct btrfsic_state *state,
+ struct btrfsic_block *block,
+ struct btrfsic_block_data_ctx *block_ctx,
+ u32 item_offset, int force_iodone_flag);
+static int btrfsic_map_block(struct btrfsic_state *state, u64 bytenr, u32 len,
+ struct btrfsic_block_data_ctx *block_ctx_out,
+ int mirror_num);
+static int btrfsic_map_superblock(struct btrfsic_state *state, u64 bytenr,
+ u32 len, struct block_device *bdev,
+ struct btrfsic_block_data_ctx *block_ctx_out);
+static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx);
+static int btrfsic_read_block(struct btrfsic_state *state,
+ struct btrfsic_block_data_ctx *block_ctx);
+static void btrfsic_dump_database(struct btrfsic_state *state);
+static int btrfsic_test_for_metadata(struct btrfsic_state *state,
+ const u8 *data, unsigned int size);
+static void btrfsic_process_written_block(struct btrfsic_dev_state *dev_state,
+ u64 dev_bytenr, u8 *mapped_data,
+ unsigned int len, struct bio *bio,
+ int *bio_is_patched,
+ struct buffer_head *bh,
+ int submit_bio_bh_rw);
+static int btrfsic_process_written_superblock(
+ struct btrfsic_state *state,
+ struct btrfsic_block *const block,
+ struct btrfs_super_block *const super_hdr);
+static void btrfsic_bio_end_io(struct bio *bp, int bio_error_status);
+static void btrfsic_bh_end_io(struct buffer_head *bh, int uptodate);
+static int btrfsic_is_block_ref_by_superblock(const struct btrfsic_state *state,
+ const struct btrfsic_block *block,
+ int recursion_level);
+static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state,
+ struct btrfsic_block *const block,
+ int recursion_level);
+static void btrfsic_print_add_link(const struct btrfsic_state *state,
+ const struct btrfsic_block_link *l);
+static void btrfsic_print_rem_link(const struct btrfsic_state *state,
+ const struct btrfsic_block_link *l);
+static char btrfsic_get_block_type(const struct btrfsic_state *state,
+ const struct btrfsic_block *block);
+static void btrfsic_dump_tree(const struct btrfsic_state *state);
+static void btrfsic_dump_tree_sub(const struct btrfsic_state *state,
+ const struct btrfsic_block *block,
+ int indent_level);
+static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add(
+ struct btrfsic_state *state,
+ struct btrfsic_block_data_ctx *next_block_ctx,
+ struct btrfsic_block *next_block,
+ struct btrfsic_block *from_block,
+ u64 parent_generation);
+static struct btrfsic_block *btrfsic_block_lookup_or_add(
+ struct btrfsic_state *state,
+ struct btrfsic_block_data_ctx *block_ctx,
+ const char *additional_string,
+ int is_metadata,
+ int is_iodone,
+ int never_written,
+ int mirror_num,
+ int *was_created);
+static int btrfsic_process_superblock_dev_mirror(
+ struct btrfsic_state *state,
+ struct btrfsic_dev_state *dev_state,
+ struct btrfs_device *device,
+ int superblock_mirror_num,
+ struct btrfsic_dev_state **selected_dev_state,
+ struct btrfs_super_block *selected_super);
+static struct btrfsic_dev_state *btrfsic_dev_state_lookup(
+ struct block_device *bdev);
+static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state,
+ u64 bytenr,
+ struct btrfsic_dev_state *dev_state,
+ u64 dev_bytenr, char *data);
+
+static struct mutex btrfsic_mutex;
+static int btrfsic_is_initialized;
+static struct btrfsic_dev_state_hashtable btrfsic_dev_state_hashtable;
+
+
+static void btrfsic_block_init(struct btrfsic_block *b)
+{
+ b->magic_num = BTRFSIC_BLOCK_MAGIC_NUMBER;
+ b->dev_state = NULL;
+ b->dev_bytenr = 0;
+ b->logical_bytenr = 0;
+ b->generation = BTRFSIC_GENERATION_UNKNOWN;
+ b->disk_key.objectid = 0;
+ b->disk_key.type = 0;
+ b->disk_key.offset = 0;
+ b->is_metadata = 0;
+ b->is_superblock = 0;
+ b->is_iodone = 0;
+ b->iodone_w_error = 0;
+ b->never_written = 0;
+ b->mirror_num = 0;
+ b->next_in_same_bio = NULL;
+ b->orig_bio_bh_private = NULL;
+ b->orig_bio_bh_end_io.bio = NULL;
+ INIT_LIST_HEAD(&b->collision_resolving_node);
+ INIT_LIST_HEAD(&b->all_blocks_node);
+ INIT_LIST_HEAD(&b->ref_to_list);
+ INIT_LIST_HEAD(&b->ref_from_list);
+ b->submit_bio_bh_rw = 0;
+ b->flush_gen = 0;
+}
+
+static struct btrfsic_block *btrfsic_block_alloc(void)
+{
+ struct btrfsic_block *b;
+
+ b = kzalloc(sizeof(*b), GFP_NOFS);
+ if (NULL != b)
+ btrfsic_block_init(b);
+
+ return b;
+}
+
+static void btrfsic_block_free(struct btrfsic_block *b)
+{
+ BUG_ON(!(NULL == b || BTRFSIC_BLOCK_MAGIC_NUMBER == b->magic_num));
+ kfree(b);
+}
+
+static void btrfsic_block_link_init(struct btrfsic_block_link *l)
+{
+ l->magic_num = BTRFSIC_BLOCK_LINK_MAGIC_NUMBER;
+ l->ref_cnt = 1;
+ INIT_LIST_HEAD(&l->node_ref_to);
+ INIT_LIST_HEAD(&l->node_ref_from);
+ INIT_LIST_HEAD(&l->collision_resolving_node);
+ l->block_ref_to = NULL;
+ l->block_ref_from = NULL;
+}
+
+static struct btrfsic_block_link *btrfsic_block_link_alloc(void)
+{
+ struct btrfsic_block_link *l;
+
+ l = kzalloc(sizeof(*l), GFP_NOFS);
+ if (NULL != l)
+ btrfsic_block_link_init(l);
+
+ return l;
+}
+
+static void btrfsic_block_link_free(struct btrfsic_block_link *l)
+{
+ BUG_ON(!(NULL == l || BTRFSIC_BLOCK_LINK_MAGIC_NUMBER == l->magic_num));
+ kfree(l);
+}
+
+static void btrfsic_dev_state_init(struct btrfsic_dev_state *ds)
+{
+ ds->magic_num = BTRFSIC_DEV2STATE_MAGIC_NUMBER;
+ ds->bdev = NULL;
+ ds->state = NULL;
+ ds->name[0] = '\0';
+ INIT_LIST_HEAD(&ds->collision_resolving_node);
+ ds->last_flush_gen = 0;
+ btrfsic_block_init(&ds->dummy_block_for_bio_bh_flush);
+ ds->dummy_block_for_bio_bh_flush.is_iodone = 1;
+ ds->dummy_block_for_bio_bh_flush.dev_state = ds;
+}
+
+static struct btrfsic_dev_state *btrfsic_dev_state_alloc(void)
+{
+ struct btrfsic_dev_state *ds;
+
+ ds = kzalloc(sizeof(*ds), GFP_NOFS);
+ if (NULL != ds)
+ btrfsic_dev_state_init(ds);
+
+ return ds;
+}
+
+static void btrfsic_dev_state_free(struct btrfsic_dev_state *ds)
+{
+ BUG_ON(!(NULL == ds ||
+ BTRFSIC_DEV2STATE_MAGIC_NUMBER == ds->magic_num));
+ kfree(ds);
+}
+
+static void btrfsic_block_hashtable_init(struct btrfsic_block_hashtable *h)
+{
+ int i;
+
+ for (i = 0; i < BTRFSIC_BLOCK_HASHTABLE_SIZE; i++)
+ INIT_LIST_HEAD(h->table + i);
+}
+
+static void btrfsic_block_hashtable_add(struct btrfsic_block *b,
+ struct btrfsic_block_hashtable *h)
+{
+ const unsigned int hashval =
+ (((unsigned int)(b->dev_bytenr >> 16)) ^
+ ((unsigned int)((uintptr_t)b->dev_state->bdev))) &
+ (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1);
+
+ list_add(&b->collision_resolving_node, h->table + hashval);
+}
+
+static void btrfsic_block_hashtable_remove(struct btrfsic_block *b)
+{
+ list_del(&b->collision_resolving_node);
+}
+
+static struct btrfsic_block *btrfsic_block_hashtable_lookup(
+ struct block_device *bdev,
+ u64 dev_bytenr,
+ struct btrfsic_block_hashtable *h)
+{
+ const unsigned int hashval =
+ (((unsigned int)(dev_bytenr >> 16)) ^
+ ((unsigned int)((uintptr_t)bdev))) &
+ (BTRFSIC_BLOCK_HASHTABLE_SIZE - 1);
+ struct list_head *elem;
+
+ list_for_each(elem, h->table + hashval) {
+ struct btrfsic_block *const b =
+ list_entry(elem, struct btrfsic_block,
+ collision_resolving_node);
+
+ if (b->dev_state->bdev == bdev && b->dev_bytenr == dev_bytenr)
+ return b;
+ }
+
+ return NULL;
+}
+
+static void btrfsic_block_link_hashtable_init(
+ struct btrfsic_block_link_hashtable *h)
+{
+ int i;
+
+ for (i = 0; i < BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE; i++)
+ INIT_LIST_HEAD(h->table + i);
+}
+
+static void btrfsic_block_link_hashtable_add(
+ struct btrfsic_block_link *l,
+ struct btrfsic_block_link_hashtable *h)
+{
+ const unsigned int hashval =
+ (((unsigned int)(l->block_ref_to->dev_bytenr >> 16)) ^
+ ((unsigned int)(l->block_ref_from->dev_bytenr >> 16)) ^
+ ((unsigned int)((uintptr_t)l->block_ref_to->dev_state->bdev)) ^
+ ((unsigned int)((uintptr_t)l->block_ref_from->dev_state->bdev)))
+ & (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1);
+
+ BUG_ON(NULL == l->block_ref_to);
+ BUG_ON(NULL == l->block_ref_from);
+ list_add(&l->collision_resolving_node, h->table + hashval);
+}
+
+static void btrfsic_block_link_hashtable_remove(struct btrfsic_block_link *l)
+{
+ list_del(&l->collision_resolving_node);
+}
+
+static struct btrfsic_block_link *btrfsic_block_link_hashtable_lookup(
+ struct block_device *bdev_ref_to,
+ u64 dev_bytenr_ref_to,
+ struct block_device *bdev_ref_from,
+ u64 dev_bytenr_ref_from,
+ struct btrfsic_block_link_hashtable *h)
+{
+ const unsigned int hashval =
+ (((unsigned int)(dev_bytenr_ref_to >> 16)) ^
+ ((unsigned int)(dev_bytenr_ref_from >> 16)) ^
+ ((unsigned int)((uintptr_t)bdev_ref_to)) ^
+ ((unsigned int)((uintptr_t)bdev_ref_from))) &
+ (BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE - 1);
+ struct list_head *elem;
+
+ list_for_each(elem, h->table + hashval) {
+ struct btrfsic_block_link *const l =
+ list_entry(elem, struct btrfsic_block_link,
+ collision_resolving_node);
+
+ BUG_ON(NULL == l->block_ref_to);
+ BUG_ON(NULL == l->block_ref_from);
+ if (l->block_ref_to->dev_state->bdev == bdev_ref_to &&
+ l->block_ref_to->dev_bytenr == dev_bytenr_ref_to &&
+ l->block_ref_from->dev_state->bdev == bdev_ref_from &&
+ l->block_ref_from->dev_bytenr == dev_bytenr_ref_from)
+ return l;
+ }
+
+ return NULL;
+}
+
+static void btrfsic_dev_state_hashtable_init(
+ struct btrfsic_dev_state_hashtable *h)
+{
+ int i;
+
+ for (i = 0; i < BTRFSIC_DEV2STATE_HASHTABLE_SIZE; i++)
+ INIT_LIST_HEAD(h->table + i);
+}
+
+static void btrfsic_dev_state_hashtable_add(
+ struct btrfsic_dev_state *ds,
+ struct btrfsic_dev_state_hashtable *h)
+{
+ const unsigned int hashval =
+ (((unsigned int)((uintptr_t)ds->bdev)) &
+ (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1));
+
+ list_add(&ds->collision_resolving_node, h->table + hashval);
+}
+
+static void btrfsic_dev_state_hashtable_remove(struct btrfsic_dev_state *ds)
+{
+ list_del(&ds->collision_resolving_node);
+}
+
+static struct btrfsic_dev_state *btrfsic_dev_state_hashtable_lookup(
+ struct block_device *bdev,
+ struct btrfsic_dev_state_hashtable *h)
+{
+ const unsigned int hashval =
+ (((unsigned int)((uintptr_t)bdev)) &
+ (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1));
+ struct list_head *elem;
+
+ list_for_each(elem, h->table + hashval) {
+ struct btrfsic_dev_state *const ds =
+ list_entry(elem, struct btrfsic_dev_state,
+ collision_resolving_node);
+
+ if (ds->bdev == bdev)
+ return ds;
+ }
+
+ return NULL;
+}
+
+static int btrfsic_process_superblock(struct btrfsic_state *state,
+ struct btrfs_fs_devices *fs_devices)
+{
+ int ret;
+ struct btrfs_super_block *selected_super;
+ struct list_head *dev_head = &fs_devices->devices;
+ struct btrfs_device *device;
+ struct btrfsic_dev_state *selected_dev_state = NULL;
+ int pass;
+
+ BUG_ON(NULL == state);
+ selected_super = kmalloc(sizeof(*selected_super), GFP_NOFS);
+ if (NULL == selected_super) {
+ printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
+ return -1;
+ }
+
+ list_for_each_entry(device, dev_head, dev_list) {
+ int i;
+ struct btrfsic_dev_state *dev_state;
+
+ if (!device->bdev || !device->name)
+ continue;
+
+ dev_state = btrfsic_dev_state_lookup(device->bdev);
+ BUG_ON(NULL == dev_state);
+ for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
+ ret = btrfsic_process_superblock_dev_mirror(
+ state, dev_state, device, i,
+ &selected_dev_state, selected_super);
+ if (0 != ret && 0 == i) {
+ kfree(selected_super);
+ return ret;
+ }
+ }
+ }
+
+ if (NULL == state->latest_superblock) {
+ printk(KERN_INFO "btrfsic: no superblock found!\n");
+ kfree(selected_super);
+ return -1;
+ }
+
+ state->csum_size = btrfs_super_csum_size(selected_super);
+
+ for (pass = 0; pass < 3; pass++) {
+ int num_copies;
+ int mirror_num;
+ u64 next_bytenr;
+
+ switch (pass) {
+ case 0:
+ next_bytenr = btrfs_super_root(selected_super);
+ if (state->print_mask &
+ BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
+ printk(KERN_INFO "root@%llu\n",
+ (unsigned long long)next_bytenr);
+ break;
+ case 1:
+ next_bytenr = btrfs_super_chunk_root(selected_super);
+ if (state->print_mask &
+ BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
+ printk(KERN_INFO "chunk@%llu\n",
+ (unsigned long long)next_bytenr);
+ break;
+ case 2:
+ next_bytenr = btrfs_super_log_root(selected_super);
+ if (0 == next_bytenr)
+ continue;
+ if (state->print_mask &
+ BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
+ printk(KERN_INFO "log@%llu\n",
+ (unsigned long long)next_bytenr);
+ break;
+ }
+
+ num_copies =
+ btrfs_num_copies(&state->root->fs_info->mapping_tree,
+ next_bytenr, PAGE_SIZE);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
+ printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
+ (unsigned long long)next_bytenr, num_copies);
+
+ for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
+ struct btrfsic_block *next_block;
+ struct btrfsic_block_data_ctx tmp_next_block_ctx;
+ struct btrfsic_block_link *l;
+ struct btrfs_header *hdr;
+
+ ret = btrfsic_map_block(state, next_bytenr, PAGE_SIZE,
+ &tmp_next_block_ctx,
+ mirror_num);
+ if (ret) {
+ printk(KERN_INFO "btrfsic:"
+ " btrfsic_map_block(root @%llu,"
+ " mirror %d) failed!\n",
+ (unsigned long long)next_bytenr,
+ mirror_num);
+ kfree(selected_super);
+ return -1;
+ }
+
+ next_block = btrfsic_block_hashtable_lookup(
+ tmp_next_block_ctx.dev->bdev,
+ tmp_next_block_ctx.dev_bytenr,
+ &state->block_hashtable);
+ BUG_ON(NULL == next_block);
+
+ l = btrfsic_block_link_hashtable_lookup(
+ tmp_next_block_ctx.dev->bdev,
+ tmp_next_block_ctx.dev_bytenr,
+ state->latest_superblock->dev_state->
+ bdev,
+ state->latest_superblock->dev_bytenr,
+ &state->block_link_hashtable);
+ BUG_ON(NULL == l);
+
+ ret = btrfsic_read_block(state, &tmp_next_block_ctx);
+ if (ret < (int)BTRFSIC_BLOCK_SIZE) {
+ printk(KERN_INFO
+ "btrfsic: read @logical %llu failed!\n",
+ (unsigned long long)
+ tmp_next_block_ctx.start);
+ btrfsic_release_block_ctx(&tmp_next_block_ctx);
+ kfree(selected_super);
+ return -1;
+ }
+
+ hdr = (struct btrfs_header *)tmp_next_block_ctx.data;
+ ret = btrfsic_process_metablock(state,
+ next_block,
+ &tmp_next_block_ctx,
+ hdr,
+ BTRFS_MAX_LEVEL + 3, 1);
+ btrfsic_release_block_ctx(&tmp_next_block_ctx);
+ }
+ }
+
+ kfree(selected_super);
+ return ret;
+}
+
+static int btrfsic_process_superblock_dev_mirror(
+ struct btrfsic_state *state,
+ struct btrfsic_dev_state *dev_state,
+ struct btrfs_device *device,
+ int superblock_mirror_num,
+ struct btrfsic_dev_state **selected_dev_state,
+ struct btrfs_super_block *selected_super)
+{
+ struct btrfs_super_block *super_tmp;
+ u64 dev_bytenr;
+ struct buffer_head *bh;
+ struct btrfsic_block *superblock_tmp;
+ int pass;
+ struct block_device *const superblock_bdev = device->bdev;
+
+ /* super block bytenr is always the unmapped device bytenr */
+ dev_bytenr = btrfs_sb_offset(superblock_mirror_num);
+ bh = __bread(superblock_bdev, dev_bytenr / 4096, 4096);
+ if (NULL == bh)
+ return -1;
+ super_tmp = (struct btrfs_super_block *)
+ (bh->b_data + (dev_bytenr & 4095));
+
+ if (btrfs_super_bytenr(super_tmp) != dev_bytenr ||
+ strncmp((char *)(&(super_tmp->magic)), BTRFS_MAGIC,
+ sizeof(super_tmp->magic)) ||
+ memcmp(device->uuid, super_tmp->dev_item.uuid, BTRFS_UUID_SIZE)) {
+ brelse(bh);
+ return 0;
+ }
+
+ superblock_tmp =
+ btrfsic_block_hashtable_lookup(superblock_bdev,
+ dev_bytenr,
+ &state->block_hashtable);
+ if (NULL == superblock_tmp) {
+ superblock_tmp = btrfsic_block_alloc();
+ if (NULL == superblock_tmp) {
+ printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
+ brelse(bh);
+ return -1;
+ }
+ /* for superblock, only the dev_bytenr makes sense */
+ superblock_tmp->dev_bytenr = dev_bytenr;
+ superblock_tmp->dev_state = dev_state;
+ superblock_tmp->logical_bytenr = dev_bytenr;
+ superblock_tmp->generation = btrfs_super_generation(super_tmp);
+ superblock_tmp->is_metadata = 1;
+ superblock_tmp->is_superblock = 1;
+ superblock_tmp->is_iodone = 1;
+ superblock_tmp->never_written = 0;
+ superblock_tmp->mirror_num = 1 + superblock_mirror_num;
+ if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
+ printk(KERN_INFO "New initial S-block (bdev %p, %s)"
+ " @%llu (%s/%llu/%d)\n",
+ superblock_bdev, device->name,
+ (unsigned long long)dev_bytenr,
+ dev_state->name,
+ (unsigned long long)dev_bytenr,
+ superblock_mirror_num);
+ list_add(&superblock_tmp->all_blocks_node,
+ &state->all_blocks_list);
+ btrfsic_block_hashtable_add(superblock_tmp,
+ &state->block_hashtable);
+ }
+
+ /* select the one with the highest generation field */
+ if (btrfs_super_generation(super_tmp) >
+ state->max_superblock_generation ||
+ 0 == state->max_superblock_generation) {
+ memcpy(selected_super, super_tmp, sizeof(*selected_super));
+ *selected_dev_state = dev_state;
+ state->max_superblock_generation =
+ btrfs_super_generation(super_tmp);
+ state->latest_superblock = superblock_tmp;
+ }
+
+ for (pass = 0; pass < 3; pass++) {
+ u64 next_bytenr;
+ int num_copies;
+ int mirror_num;
+ const char *additional_string = NULL;
+ struct btrfs_disk_key tmp_disk_key;
+
+ tmp_disk_key.type = BTRFS_ROOT_ITEM_KEY;
+ tmp_disk_key.offset = 0;
+ switch (pass) {
+ case 0:
+ tmp_disk_key.objectid =
+ cpu_to_le64(BTRFS_ROOT_TREE_OBJECTID);
+ additional_string = "initial root ";
+ next_bytenr = btrfs_super_root(super_tmp);
+ break;
+ case 1:
+ tmp_disk_key.objectid =
+ cpu_to_le64(BTRFS_CHUNK_TREE_OBJECTID);
+ additional_string = "initial chunk ";
+ next_bytenr = btrfs_super_chunk_root(super_tmp);
+ break;
+ case 2:
+ tmp_disk_key.objectid =
+ cpu_to_le64(BTRFS_TREE_LOG_OBJECTID);
+ additional_string = "initial log ";
+ next_bytenr = btrfs_super_log_root(super_tmp);
+ if (0 == next_bytenr)
+ continue;
+ break;
+ }
+
+ num_copies =
+ btrfs_num_copies(&state->root->fs_info->mapping_tree,
+ next_bytenr, PAGE_SIZE);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
+ printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
+ (unsigned long long)next_bytenr, num_copies);
+ for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
+ struct btrfsic_block *next_block;
+ struct btrfsic_block_data_ctx tmp_next_block_ctx;
+ struct btrfsic_block_link *l;
+
+ if (btrfsic_map_block(state, next_bytenr, PAGE_SIZE,
+ &tmp_next_block_ctx,
+ mirror_num)) {
+ printk(KERN_INFO "btrfsic: btrfsic_map_block("
+ "bytenr @%llu, mirror %d) failed!\n",
+ (unsigned long long)next_bytenr,
+ mirror_num);
+ brelse(bh);
+ return -1;
+ }
+
+ next_block = btrfsic_block_lookup_or_add(
+ state, &tmp_next_block_ctx,
+ additional_string, 1, 1, 0,
+ mirror_num, NULL);
+ if (NULL == next_block) {
+ btrfsic_release_block_ctx(&tmp_next_block_ctx);
+ brelse(bh);
+ return -1;
+ }
+
+ next_block->disk_key = tmp_disk_key;
+ next_block->generation = BTRFSIC_GENERATION_UNKNOWN;
+ l = btrfsic_block_link_lookup_or_add(
+ state, &tmp_next_block_ctx,
+ next_block, superblock_tmp,
+ BTRFSIC_GENERATION_UNKNOWN);
+ btrfsic_release_block_ctx(&tmp_next_block_ctx);
+ if (NULL == l) {
+ brelse(bh);
+ return -1;
+ }
+ }
+ }
+ if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_ALL_TREES)
+ btrfsic_dump_tree_sub(state, superblock_tmp, 0);
+
+ brelse(bh);
+ return 0;
+}
+
+static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void)
+{
+ struct btrfsic_stack_frame *sf;
+
+ sf = kzalloc(sizeof(*sf), GFP_NOFS);
+ if (NULL == sf)
+ printk(KERN_INFO "btrfsic: alloc memory failed!\n");
+ else
+ sf->magic = BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER;
+ return sf;
+}
+
+static void btrfsic_stack_frame_free(struct btrfsic_stack_frame *sf)
+{
+ BUG_ON(!(NULL == sf ||
+ BTRFSIC_BLOCK_STACK_FRAME_MAGIC_NUMBER == sf->magic));
+ kfree(sf);
+}
+
+static int btrfsic_process_metablock(
+ struct btrfsic_state *state,
+ struct btrfsic_block *const first_block,
+ struct btrfsic_block_data_ctx *const first_block_ctx,
+ struct btrfs_header *const first_hdr,
+ int first_limit_nesting, int force_iodone_flag)
+{
+ struct btrfsic_stack_frame initial_stack_frame = { 0 };
+ struct btrfsic_stack_frame *sf;
+ struct btrfsic_stack_frame *next_stack;
+
+ sf = &initial_stack_frame;
+ sf->error = 0;
+ sf->i = -1;
+ sf->limit_nesting = first_limit_nesting;
+ sf->block = first_block;
+ sf->block_ctx = first_block_ctx;
+ sf->next_block = NULL;
+ sf->hdr = first_hdr;
+ sf->prev = NULL;
+
+continue_with_new_stack_frame:
+ sf->block->generation = le64_to_cpu(sf->hdr->generation);
+ if (0 == sf->hdr->level) {
+ struct btrfs_leaf *const leafhdr =
+ (struct btrfs_leaf *)sf->hdr;
+
+ if (-1 == sf->i) {
+ sf->nr = le32_to_cpu(leafhdr->header.nritems);
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO
+ "leaf %llu items %d generation %llu"
+ " owner %llu\n",
+ (unsigned long long)
+ sf->block_ctx->start,
+ sf->nr,
+ (unsigned long long)
+ le64_to_cpu(leafhdr->header.generation),
+ (unsigned long long)
+ le64_to_cpu(leafhdr->header.owner));
+ }
+
+continue_with_current_leaf_stack_frame:
+ if (0 == sf->num_copies || sf->mirror_num > sf->num_copies) {
+ sf->i++;
+ sf->num_copies = 0;
+ }
+
+ if (sf->i < sf->nr) {
+ struct btrfs_item *disk_item = leafhdr->items + sf->i;
+ struct btrfs_disk_key *disk_key = &disk_item->key;
+ u8 type;
+ const u32 item_offset = le32_to_cpu(disk_item->offset);
+
+ type = disk_key->type;
+
+ if (BTRFS_ROOT_ITEM_KEY == type) {
+ const struct btrfs_root_item *const root_item =
+ (struct btrfs_root_item *)
+ (sf->block_ctx->data +
+ offsetof(struct btrfs_leaf, items) +
+ item_offset);
+ const u64 next_bytenr =
+ le64_to_cpu(root_item->bytenr);
+
+ sf->error =
+ btrfsic_create_link_to_next_block(
+ state,
+ sf->block,
+ sf->block_ctx,
+ next_bytenr,
+ sf->limit_nesting,
+ &sf->next_block_ctx,
+ &sf->next_block,
+ force_iodone_flag,
+ &sf->num_copies,
+ &sf->mirror_num,
+ disk_key,
+ le64_to_cpu(root_item->
+ generation));
+ if (sf->error)
+ goto one_stack_frame_backwards;
+
+ if (NULL != sf->next_block) {
+ struct btrfs_header *const next_hdr =
+ (struct btrfs_header *)
+ sf->next_block_ctx.data;
+
+ next_stack =
+ btrfsic_stack_frame_alloc();
+ if (NULL == next_stack) {
+ btrfsic_release_block_ctx(
+ &sf->
+ next_block_ctx);
+ goto one_stack_frame_backwards;
+ }
+
+ next_stack->i = -1;
+ next_stack->block = sf->next_block;
+ next_stack->block_ctx =
+ &sf->next_block_ctx;
+ next_stack->next_block = NULL;
+ next_stack->hdr = next_hdr;
+ next_stack->limit_nesting =
+ sf->limit_nesting - 1;
+ next_stack->prev = sf;
+ sf = next_stack;
+ goto continue_with_new_stack_frame;
+ }
+ } else if (BTRFS_EXTENT_DATA_KEY == type &&
+ state->include_extent_data) {
+ sf->error = btrfsic_handle_extent_data(
+ state,
+ sf->block,
+ sf->block_ctx,
+ item_offset,
+ force_iodone_flag);
+ if (sf->error)
+ goto one_stack_frame_backwards;
+ }
+
+ goto continue_with_current_leaf_stack_frame;
+ }
+ } else {
+ struct btrfs_node *const nodehdr = (struct btrfs_node *)sf->hdr;
+
+ if (-1 == sf->i) {
+ sf->nr = le32_to_cpu(nodehdr->header.nritems);
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO "node %llu level %d items %d"
+ " generation %llu owner %llu\n",
+ (unsigned long long)
+ sf->block_ctx->start,
+ nodehdr->header.level, sf->nr,
+ (unsigned long long)
+ le64_to_cpu(nodehdr->header.generation),
+ (unsigned long long)
+ le64_to_cpu(nodehdr->header.owner));
+ }
+
+continue_with_current_node_stack_frame:
+ if (0 == sf->num_copies || sf->mirror_num > sf->num_copies) {
+ sf->i++;
+ sf->num_copies = 0;
+ }
+
+ if (sf->i < sf->nr) {
+ struct btrfs_key_ptr *disk_key_ptr =
+ nodehdr->ptrs + sf->i;
+ const u64 next_bytenr =
+ le64_to_cpu(disk_key_ptr->blockptr);
+
+ sf->error = btrfsic_create_link_to_next_block(
+ state,
+ sf->block,
+ sf->block_ctx,
+ next_bytenr,
+ sf->limit_nesting,
+ &sf->next_block_ctx,
+ &sf->next_block,
+ force_iodone_flag,
+ &sf->num_copies,
+ &sf->mirror_num,
+ &disk_key_ptr->key,
+ le64_to_cpu(disk_key_ptr->generation));
+ if (sf->error)
+ goto one_stack_frame_backwards;
+
+ if (NULL != sf->next_block) {
+ struct btrfs_header *const next_hdr =
+ (struct btrfs_header *)
+ sf->next_block_ctx.data;
+
+ next_stack = btrfsic_stack_frame_alloc();
+ if (NULL == next_stack)
+ goto one_stack_frame_backwards;
+
+ next_stack->i = -1;
+ next_stack->block = sf->next_block;
+ next_stack->block_ctx = &sf->next_block_ctx;
+ next_stack->next_block = NULL;
+ next_stack->hdr = next_hdr;
+ next_stack->limit_nesting =
+ sf->limit_nesting - 1;
+ next_stack->prev = sf;
+ sf = next_stack;
+ goto continue_with_new_stack_frame;
+ }
+
+ goto continue_with_current_node_stack_frame;
+ }
+ }
+
+one_stack_frame_backwards:
+ if (NULL != sf->prev) {
+ struct btrfsic_stack_frame *const prev = sf->prev;
+
+ /* the one for the initial block is freed in the caller */
+ btrfsic_release_block_ctx(sf->block_ctx);
+
+ if (sf->error) {
+ prev->error = sf->error;
+ btrfsic_stack_frame_free(sf);
+ sf = prev;
+ goto one_stack_frame_backwards;
+ }
+
+ btrfsic_stack_frame_free(sf);
+ sf = prev;
+ goto continue_with_new_stack_frame;
+ } else {
+ BUG_ON(&initial_stack_frame != sf);
+ }
+
+ return sf->error;
+}
+
+static int btrfsic_create_link_to_next_block(
+ struct btrfsic_state *state,
+ struct btrfsic_block *block,
+ struct btrfsic_block_data_ctx *block_ctx,
+ u64 next_bytenr,
+ int limit_nesting,
+ struct btrfsic_block_data_ctx *next_block_ctx,
+ struct btrfsic_block **next_blockp,
+ int force_iodone_flag,
+ int *num_copiesp, int *mirror_nump,
+ struct btrfs_disk_key *disk_key,
+ u64 parent_generation)
+{
+ struct btrfsic_block *next_block = NULL;
+ int ret;
+ struct btrfsic_block_link *l;
+ int did_alloc_block_link;
+ int block_was_created;
+
+ *next_blockp = NULL;
+ if (0 == *num_copiesp) {
+ *num_copiesp =
+ btrfs_num_copies(&state->root->fs_info->mapping_tree,
+ next_bytenr, PAGE_SIZE);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
+ printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
+ (unsigned long long)next_bytenr, *num_copiesp);
+ *mirror_nump = 1;
+ }
+
+ if (*mirror_nump > *num_copiesp)
+ return 0;
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO
+ "btrfsic_create_link_to_next_block(mirror_num=%d)\n",
+ *mirror_nump);
+ ret = btrfsic_map_block(state, next_bytenr,
+ BTRFSIC_BLOCK_SIZE,
+ next_block_ctx, *mirror_nump);
+ if (ret) {
+ printk(KERN_INFO
+ "btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n",
+ (unsigned long long)next_bytenr, *mirror_nump);
+ btrfsic_release_block_ctx(next_block_ctx);
+ *next_blockp = NULL;
+ return -1;
+ }
+
+ next_block = btrfsic_block_lookup_or_add(state,
+ next_block_ctx, "referenced ",
+ 1, force_iodone_flag,
+ !force_iodone_flag,
+ *mirror_nump,
+ &block_was_created);
+ if (NULL == next_block) {
+ btrfsic_release_block_ctx(next_block_ctx);
+ *next_blockp = NULL;
+ return -1;
+ }
+ if (block_was_created) {
+ l = NULL;
+ next_block->generation = BTRFSIC_GENERATION_UNKNOWN;
+ } else {
+ if (next_block->logical_bytenr != next_bytenr &&
+ !(!next_block->is_metadata &&
+ 0 == next_block->logical_bytenr)) {
+ printk(KERN_INFO
+ "Referenced block @%llu (%s/%llu/%d)"
+ " found in hash table, %c,"
+ " bytenr mismatch (!= stored %llu).\n",
+ (unsigned long long)next_bytenr,
+ next_block_ctx->dev->name,
+ (unsigned long long)next_block_ctx->dev_bytenr,
+ *mirror_nump,
+ btrfsic_get_block_type(state, next_block),
+ (unsigned long long)next_block->logical_bytenr);
+ } else if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO
+ "Referenced block @%llu (%s/%llu/%d)"
+ " found in hash table, %c.\n",
+ (unsigned long long)next_bytenr,
+ next_block_ctx->dev->name,
+ (unsigned long long)next_block_ctx->dev_bytenr,
+ *mirror_nump,
+ btrfsic_get_block_type(state, next_block));
+ next_block->logical_bytenr = next_bytenr;
+
+ next_block->mirror_num = *mirror_nump;
+ l = btrfsic_block_link_hashtable_lookup(
+ next_block_ctx->dev->bdev,
+ next_block_ctx->dev_bytenr,
+ block_ctx->dev->bdev,
+ block_ctx->dev_bytenr,
+ &state->block_link_hashtable);
+ }
+
+ next_block->disk_key = *disk_key;
+ if (NULL == l) {
+ l = btrfsic_block_link_alloc();
+ if (NULL == l) {
+ printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
+ btrfsic_release_block_ctx(next_block_ctx);
+ *next_blockp = NULL;
+ return -1;
+ }
+
+ did_alloc_block_link = 1;
+ l->block_ref_to = next_block;
+ l->block_ref_from = block;
+ l->ref_cnt = 1;
+ l->parent_generation = parent_generation;
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ btrfsic_print_add_link(state, l);
+
+ list_add(&l->node_ref_to, &block->ref_to_list);
+ list_add(&l->node_ref_from, &next_block->ref_from_list);
+
+ btrfsic_block_link_hashtable_add(l,
+ &state->block_link_hashtable);
+ } else {
+ did_alloc_block_link = 0;
+ if (0 == limit_nesting) {
+ l->ref_cnt++;
+ l->parent_generation = parent_generation;
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ btrfsic_print_add_link(state, l);
+ }
+ }
+
+ if (limit_nesting > 0 && did_alloc_block_link) {
+ ret = btrfsic_read_block(state, next_block_ctx);
+ if (ret < (int)BTRFSIC_BLOCK_SIZE) {
+ printk(KERN_INFO
+ "btrfsic: read block @logical %llu failed!\n",
+ (unsigned long long)next_bytenr);
+ btrfsic_release_block_ctx(next_block_ctx);
+ *next_blockp = NULL;
+ return -1;
+ }
+
+ *next_blockp = next_block;
+ } else {
+ *next_blockp = NULL;
+ }
+ (*mirror_nump)++;
+
+ return 0;
+}
+
+static int btrfsic_handle_extent_data(
+ struct btrfsic_state *state,
+ struct btrfsic_block *block,
+ struct btrfsic_block_data_ctx *block_ctx,
+ u32 item_offset, int force_iodone_flag)
+{
+ int ret;
+ struct btrfs_file_extent_item *file_extent_item =
+ (struct btrfs_file_extent_item *)(block_ctx->data +
+ offsetof(struct btrfs_leaf,
+ items) + item_offset);
+ u64 next_bytenr =
+ le64_to_cpu(file_extent_item->disk_bytenr) +
+ le64_to_cpu(file_extent_item->offset);
+ u64 num_bytes = le64_to_cpu(file_extent_item->num_bytes);
+ u64 generation = le64_to_cpu(file_extent_item->generation);
+ struct btrfsic_block_link *l;
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE)
+ printk(KERN_INFO "extent_data: type %u, disk_bytenr = %llu,"
+ " offset = %llu, num_bytes = %llu\n",
+ file_extent_item->type,
+ (unsigned long long)
+ le64_to_cpu(file_extent_item->disk_bytenr),
+ (unsigned long long)
+ le64_to_cpu(file_extent_item->offset),
+ (unsigned long long)
+ le64_to_cpu(file_extent_item->num_bytes));
+ if (BTRFS_FILE_EXTENT_REG != file_extent_item->type ||
+ ((u64)0) == le64_to_cpu(file_extent_item->disk_bytenr))
+ return 0;
+ while (num_bytes > 0) {
+ u32 chunk_len;
+ int num_copies;
+ int mirror_num;
+
+ if (num_bytes > BTRFSIC_BLOCK_SIZE)
+ chunk_len = BTRFSIC_BLOCK_SIZE;
+ else
+ chunk_len = num_bytes;
+
+ num_copies =
+ btrfs_num_copies(&state->root->fs_info->mapping_tree,
+ next_bytenr, PAGE_SIZE);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
+ printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
+ (unsigned long long)next_bytenr, num_copies);
+ for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
+ struct btrfsic_block_data_ctx next_block_ctx;
+ struct btrfsic_block *next_block;
+ int block_was_created;
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO "btrfsic_handle_extent_data("
+ "mirror_num=%d)\n", mirror_num);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE)
+ printk(KERN_INFO
+ "\tdisk_bytenr = %llu, num_bytes %u\n",
+ (unsigned long long)next_bytenr,
+ chunk_len);
+ ret = btrfsic_map_block(state, next_bytenr,
+ chunk_len, &next_block_ctx,
+ mirror_num);
+ if (ret) {
+ printk(KERN_INFO
+ "btrfsic: btrfsic_map_block(@%llu,"
+ " mirror=%d) failed!\n",
+ (unsigned long long)next_bytenr,
+ mirror_num);
+ return -1;
+ }
+
+ next_block = btrfsic_block_lookup_or_add(
+ state,
+ &next_block_ctx,
+ "referenced ",
+ 0,
+ force_iodone_flag,
+ !force_iodone_flag,
+ mirror_num,
+ &block_was_created);
+ if (NULL == next_block) {
+ printk(KERN_INFO
+ "btrfsic: error, kmalloc failed!\n");
+ btrfsic_release_block_ctx(&next_block_ctx);
+ return -1;
+ }
+ if (!block_was_created) {
+ if (next_block->logical_bytenr != next_bytenr &&
+ !(!next_block->is_metadata &&
+ 0 == next_block->logical_bytenr)) {
+ printk(KERN_INFO
+ "Referenced block"
+ " @%llu (%s/%llu/%d)"
+ " found in hash table, D,"
+ " bytenr mismatch"
+ " (!= stored %llu).\n",
+ (unsigned long long)next_bytenr,
+ next_block_ctx.dev->name,
+ (unsigned long long)
+ next_block_ctx.dev_bytenr,
+ mirror_num,
+ (unsigned long long)
+ next_block->logical_bytenr);
+ }
+ next_block->logical_bytenr = next_bytenr;
+ next_block->mirror_num = mirror_num;
+ }
+
+ l = btrfsic_block_link_lookup_or_add(state,
+ &next_block_ctx,
+ next_block, block,
+ generation);
+ btrfsic_release_block_ctx(&next_block_ctx);
+ if (NULL == l)
+ return -1;
+ }
+
+ next_bytenr += chunk_len;
+ num_bytes -= chunk_len;
+ }
+
+ return 0;
+}
+
+static int btrfsic_map_block(struct btrfsic_state *state, u64 bytenr, u32 len,
+ struct btrfsic_block_data_ctx *block_ctx_out,
+ int mirror_num)
+{
+ int ret;
+ u64 length;
+ struct btrfs_bio *multi = NULL;
+ struct btrfs_device *device;
+
+ length = len;
+ ret = btrfs_map_block(&state->root->fs_info->mapping_tree, READ,
+ bytenr, &length, &multi, mirror_num);
+
+ device = multi->stripes[0].dev;
+ block_ctx_out->dev = btrfsic_dev_state_lookup(device->bdev);
+ block_ctx_out->dev_bytenr = multi->stripes[0].physical;
+ block_ctx_out->start = bytenr;
+ block_ctx_out->len = len;
+ block_ctx_out->data = NULL;
+ block_ctx_out->bh = NULL;
+
+ if (0 == ret)
+ kfree(multi);
+ if (NULL == block_ctx_out->dev) {
+ ret = -ENXIO;
+ printk(KERN_INFO "btrfsic: error, cannot lookup dev (#1)!\n");
+ }
+
+ return ret;
+}
+
+static int btrfsic_map_superblock(struct btrfsic_state *state, u64 bytenr,
+ u32 len, struct block_device *bdev,
+ struct btrfsic_block_data_ctx *block_ctx_out)
+{
+ block_ctx_out->dev = btrfsic_dev_state_lookup(bdev);
+ block_ctx_out->dev_bytenr = bytenr;
+ block_ctx_out->start = bytenr;
+ block_ctx_out->len = len;
+ block_ctx_out->data = NULL;
+ block_ctx_out->bh = NULL;
+ if (NULL != block_ctx_out->dev) {
+ return 0;
+ } else {
+ printk(KERN_INFO "btrfsic: error, cannot lookup dev (#2)!\n");
+ return -ENXIO;
+ }
+}
+
+static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx)
+{
+ if (NULL != block_ctx->bh) {
+ brelse(block_ctx->bh);
+ block_ctx->bh = NULL;
+ }
+}
+
+static int btrfsic_read_block(struct btrfsic_state *state,
+ struct btrfsic_block_data_ctx *block_ctx)
+{
+ block_ctx->bh = NULL;
+ if (block_ctx->dev_bytenr & 4095) {
+ printk(KERN_INFO
+ "btrfsic: read_block() with unaligned bytenr %llu\n",
+ (unsigned long long)block_ctx->dev_bytenr);
+ return -1;
+ }
+ if (block_ctx->len > 4096) {
+ printk(KERN_INFO
+ "btrfsic: read_block() with too huge size %d\n",
+ block_ctx->len);
+ return -1;
+ }
+
+ block_ctx->bh = __bread(block_ctx->dev->bdev,
+ block_ctx->dev_bytenr >> 12, 4096);
+ if (NULL == block_ctx->bh)
+ return -1;
+ block_ctx->data = block_ctx->bh->b_data;
+
+ return block_ctx->len;
+}
+
+static void btrfsic_dump_database(struct btrfsic_state *state)
+{
+ struct list_head *elem_all;
+
+ BUG_ON(NULL == state);
+
+ printk(KERN_INFO "all_blocks_list:\n");
+ list_for_each(elem_all, &state->all_blocks_list) {
+ const struct btrfsic_block *const b_all =
+ list_entry(elem_all, struct btrfsic_block,
+ all_blocks_node);
+ struct list_head *elem_ref_to;
+ struct list_head *elem_ref_from;
+
+ printk(KERN_INFO "%c-block @%llu (%s/%llu/%d)\n",
+ btrfsic_get_block_type(state, b_all),
+ (unsigned long long)b_all->logical_bytenr,
+ b_all->dev_state->name,
+ (unsigned long long)b_all->dev_bytenr,
+ b_all->mirror_num);
+
+ list_for_each(elem_ref_to, &b_all->ref_to_list) {
+ const struct btrfsic_block_link *const l =
+ list_entry(elem_ref_to,
+ struct btrfsic_block_link,
+ node_ref_to);
+
+ printk(KERN_INFO " %c @%llu (%s/%llu/%d)"
+ " refers %u* to"
+ " %c @%llu (%s/%llu/%d)\n",
+ btrfsic_get_block_type(state, b_all),
+ (unsigned long long)b_all->logical_bytenr,
+ b_all->dev_state->name,
+ (unsigned long long)b_all->dev_bytenr,
+ b_all->mirror_num,
+ l->ref_cnt,
+ btrfsic_get_block_type(state, l->block_ref_to),
+ (unsigned long long)
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->name,
+ (unsigned long long)l->block_ref_to->dev_bytenr,
+ l->block_ref_to->mirror_num);
+ }
+
+ list_for_each(elem_ref_from, &b_all->ref_from_list) {
+ const struct btrfsic_block_link *const l =
+ list_entry(elem_ref_from,
+ struct btrfsic_block_link,
+ node_ref_from);
+
+ printk(KERN_INFO " %c @%llu (%s/%llu/%d)"
+ " is ref %u* from"
+ " %c @%llu (%s/%llu/%d)\n",
+ btrfsic_get_block_type(state, b_all),
+ (unsigned long long)b_all->logical_bytenr,
+ b_all->dev_state->name,
+ (unsigned long long)b_all->dev_bytenr,
+ b_all->mirror_num,
+ l->ref_cnt,
+ btrfsic_get_block_type(state, l->block_ref_from),
+ (unsigned long long)
+ l->block_ref_from->logical_bytenr,
+ l->block_ref_from->dev_state->name,
+ (unsigned long long)
+ l->block_ref_from->dev_bytenr,
+ l->block_ref_from->mirror_num);
+ }
+
+ printk(KERN_INFO "\n");
+ }
+}
+
+/*
+ * Test whether the disk block contains a tree block (leaf or node)
+ * (note that this test fails for the super block)
+ */
+static int btrfsic_test_for_metadata(struct btrfsic_state *state,
+ const u8 *data, unsigned int size)
+{
+ struct btrfs_header *h;
+ u8 csum[BTRFS_CSUM_SIZE];
+ u32 crc = ~(u32)0;
+ int fail = 0;
+ int crc_fail = 0;
+
+ h = (struct btrfs_header *)data;
+
+ if (memcmp(h->fsid, state->root->fs_info->fsid, BTRFS_UUID_SIZE))
+ fail++;
+
+ crc = crc32c(crc, data + BTRFS_CSUM_SIZE, PAGE_SIZE - BTRFS_CSUM_SIZE);
+ btrfs_csum_final(crc, csum);
+ if (memcmp(csum, h->csum, state->csum_size))
+ crc_fail++;
+
+ return fail || crc_fail;
+}
+
+static void btrfsic_process_written_block(struct btrfsic_dev_state *dev_state,
+ u64 dev_bytenr,
+ u8 *mapped_data, unsigned int len,
+ struct bio *bio,
+ int *bio_is_patched,
+ struct buffer_head *bh,
+ int submit_bio_bh_rw)
+{
+ int is_metadata;
+ struct btrfsic_block *block;
+ struct btrfsic_block_data_ctx block_ctx;
+ int ret;
+ struct btrfsic_state *state = dev_state->state;
+ struct block_device *bdev = dev_state->bdev;
+
+ WARN_ON(len > PAGE_SIZE);
+ is_metadata = (0 == btrfsic_test_for_metadata(state, mapped_data, len));
+ if (NULL != bio_is_patched)
+ *bio_is_patched = 0;
+
+ block = btrfsic_block_hashtable_lookup(bdev, dev_bytenr,
+ &state->block_hashtable);
+ if (NULL != block) {
+ u64 bytenr;
+ struct list_head *elem_ref_to;
+ struct list_head *tmp_ref_to;
+
+ if (block->is_superblock) {
+ bytenr = le64_to_cpu(((struct btrfs_super_block *)
+ mapped_data)->bytenr);
+ is_metadata = 1;
+ if (state->print_mask &
+ BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE) {
+ printk(KERN_INFO
+ "[before new superblock is written]:\n");
+ btrfsic_dump_tree_sub(state, block, 0);
+ }
+ }
+ if (is_metadata) {
+ if (!block->is_superblock) {
+ bytenr = le64_to_cpu(((struct btrfs_header *)
+ mapped_data)->bytenr);
+ btrfsic_cmp_log_and_dev_bytenr(state, bytenr,
+ dev_state,
+ dev_bytenr,
+ mapped_data);
+ }
+ if (block->logical_bytenr != bytenr) {
+ printk(KERN_INFO
+ "Written block @%llu (%s/%llu/%d)"
+ " found in hash table, %c,"
+ " bytenr mismatch"
+ " (!= stored %llu).\n",
+ (unsigned long long)bytenr,
+ dev_state->name,
+ (unsigned long long)dev_bytenr,
+ block->mirror_num,
+ btrfsic_get_block_type(state, block),
+ (unsigned long long)
+ block->logical_bytenr);
+ block->logical_bytenr = bytenr;
+ } else if (state->print_mask &
+ BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO
+ "Written block @%llu (%s/%llu/%d)"
+ " found in hash table, %c.\n",
+ (unsigned long long)bytenr,
+ dev_state->name,
+ (unsigned long long)dev_bytenr,
+ block->mirror_num,
+ btrfsic_get_block_type(state, block));
+ } else {
+ bytenr = block->logical_bytenr;
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO
+ "Written block @%llu (%s/%llu/%d)"
+ " found in hash table, %c.\n",
+ (unsigned long long)bytenr,
+ dev_state->name,
+ (unsigned long long)dev_bytenr,
+ block->mirror_num,
+ btrfsic_get_block_type(state, block));
+ }
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO
+ "ref_to_list: %cE, ref_from_list: %cE\n",
+ list_empty(&block->ref_to_list) ? ' ' : '!',
+ list_empty(&block->ref_from_list) ? ' ' : '!');
+ if (btrfsic_is_block_ref_by_superblock(state, block, 0)) {
+ printk(KERN_INFO "btrfs: attempt to overwrite %c-block"
+ " @%llu (%s/%llu/%d), old(gen=%llu,"
+ " objectid=%llu, type=%d, offset=%llu),"
+ " new(gen=%llu),"
+ " which is referenced by most recent superblock"
+ " (superblockgen=%llu)!\n",
+ btrfsic_get_block_type(state, block),
+ (unsigned long long)bytenr,
+ dev_state->name,
+ (unsigned long long)dev_bytenr,
+ block->mirror_num,
+ (unsigned long long)block->generation,
+ (unsigned long long)
+ le64_to_cpu(block->disk_key.objectid),
+ block->disk_key.type,
+ (unsigned long long)
+ le64_to_cpu(block->disk_key.offset),
+ (unsigned long long)
+ le64_to_cpu(((struct btrfs_header *)
+ mapped_data)->generation),
+ (unsigned long long)
+ state->max_superblock_generation);
+ btrfsic_dump_tree(state);
+ }
+
+ if (!block->is_iodone && !block->never_written) {
+ printk(KERN_INFO "btrfs: attempt to overwrite %c-block"
+ " @%llu (%s/%llu/%d), oldgen=%llu, newgen=%llu,"
+ " which is not yet iodone!\n",
+ btrfsic_get_block_type(state, block),
+ (unsigned long long)bytenr,
+ dev_state->name,
+ (unsigned long long)dev_bytenr,
+ block->mirror_num,
+ (unsigned long long)block->generation,
+ (unsigned long long)
+ le64_to_cpu(((struct btrfs_header *)
+ mapped_data)->generation));
+ /* it would not be safe to go on */
+ btrfsic_dump_tree(state);
+ return;
+ }
+
+ /*
+ * Clear all references of this block. Do not free
+ * the block itself even if is not referenced anymore
+ * because it still carries valueable information
+ * like whether it was ever written and IO completed.
+ */
+ list_for_each_safe(elem_ref_to, tmp_ref_to,
+ &block->ref_to_list) {
+ struct btrfsic_block_link *const l =
+ list_entry(elem_ref_to,
+ struct btrfsic_block_link,
+ node_ref_to);
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ btrfsic_print_rem_link(state, l);
+ l->ref_cnt--;
+ if (0 == l->ref_cnt) {
+ list_del(&l->node_ref_to);
+ list_del(&l->node_ref_from);
+ btrfsic_block_link_hashtable_remove(l);
+ btrfsic_block_link_free(l);
+ }
+ }
+
+ if (block->is_superblock)
+ ret = btrfsic_map_superblock(state, bytenr, len,
+ bdev, &block_ctx);
+ else
+ ret = btrfsic_map_block(state, bytenr, len,
+ &block_ctx, 0);
+ if (ret) {
+ printk(KERN_INFO
+ "btrfsic: btrfsic_map_block(root @%llu)"
+ " failed!\n", (unsigned long long)bytenr);
+ return;
+ }
+ block_ctx.data = mapped_data;
+ /* the following is required in case of writes to mirrors,
+ * use the same that was used for the lookup */
+ block_ctx.dev = dev_state;
+ block_ctx.dev_bytenr = dev_bytenr;
+
+ if (is_metadata || state->include_extent_data) {
+ block->never_written = 0;
+ block->iodone_w_error = 0;
+ if (NULL != bio) {
+ block->is_iodone = 0;
+ BUG_ON(NULL == bio_is_patched);
+ if (!*bio_is_patched) {
+ block->orig_bio_bh_private =
+ bio->bi_private;
+ block->orig_bio_bh_end_io.bio =
+ bio->bi_end_io;
+ block->next_in_same_bio = NULL;
+ bio->bi_private = block;
+ bio->bi_end_io = btrfsic_bio_end_io;
+ *bio_is_patched = 1;
+ } else {
+ struct btrfsic_block *chained_block =
+ (struct btrfsic_block *)
+ bio->bi_private;
+
+ BUG_ON(NULL == chained_block);
+ block->orig_bio_bh_private =
+ chained_block->orig_bio_bh_private;
+ block->orig_bio_bh_end_io.bio =
+ chained_block->orig_bio_bh_end_io.
+ bio;
+ block->next_in_same_bio = chained_block;
+ bio->bi_private = block;
+ }
+ } else if (NULL != bh) {
+ block->is_iodone = 0;
+ block->orig_bio_bh_private = bh->b_private;
+ block->orig_bio_bh_end_io.bh = bh->b_end_io;
+ block->next_in_same_bio = NULL;
+ bh->b_private = block;
+ bh->b_end_io = btrfsic_bh_end_io;
+ } else {
+ block->is_iodone = 1;
+ block->orig_bio_bh_private = NULL;
+ block->orig_bio_bh_end_io.bio = NULL;
+ block->next_in_same_bio = NULL;
+ }
+ }
+
+ block->flush_gen = dev_state->last_flush_gen + 1;
+ block->submit_bio_bh_rw = submit_bio_bh_rw;
+ if (is_metadata) {
+ block->logical_bytenr = bytenr;
+ block->is_metadata = 1;
+ if (block->is_superblock) {
+ ret = btrfsic_process_written_superblock(
+ state,
+ block,
+ (struct btrfs_super_block *)
+ mapped_data);
+ if (state->print_mask &
+ BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE) {
+ printk(KERN_INFO
+ "[after new superblock is written]:\n");
+ btrfsic_dump_tree_sub(state, block, 0);
+ }
+ } else {
+ block->mirror_num = 0; /* unknown */
+ ret = btrfsic_process_metablock(
+ state,
+ block,
+ &block_ctx,
+ (struct btrfs_header *)
+ block_ctx.data,
+ 0, 0);
+ }
+ if (ret)
+ printk(KERN_INFO
+ "btrfsic: btrfsic_process_metablock"
+ "(root @%llu) failed!\n",
+ (unsigned long long)dev_bytenr);
+ } else {
+ block->is_metadata = 0;
+ block->mirror_num = 0; /* unknown */
+ block->generation = BTRFSIC_GENERATION_UNKNOWN;
+ if (!state->include_extent_data
+ && list_empty(&block->ref_from_list)) {
+ /*
+ * disk block is overwritten with extent
+ * data (not meta data) and we are configured
+ * to not include extent data: take the
+ * chance and free the block's memory
+ */
+ btrfsic_block_hashtable_remove(block);
+ list_del(&block->all_blocks_node);
+ btrfsic_block_free(block);
+ }
+ }
+ btrfsic_release_block_ctx(&block_ctx);
+ } else {
+ /* block has not been found in hash table */
+ u64 bytenr;
+
+ if (!is_metadata) {
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO "Written block (%s/%llu/?)"
+ " !found in hash table, D.\n",
+ dev_state->name,
+ (unsigned long long)dev_bytenr);
+ if (!state->include_extent_data)
+ return; /* ignore that written D block */
+
+ /* this is getting ugly for the
+ * include_extent_data case... */
+ bytenr = 0; /* unknown */
+ block_ctx.start = bytenr;
+ block_ctx.len = len;
+ block_ctx.bh = NULL;
+ } else {
+ bytenr = le64_to_cpu(((struct btrfs_header *)
+ mapped_data)->bytenr);
+ btrfsic_cmp_log_and_dev_bytenr(state, bytenr, dev_state,
+ dev_bytenr,
+ mapped_data);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO
+ "Written block @%llu (%s/%llu/?)"
+ " !found in hash table, M.\n",
+ (unsigned long long)bytenr,
+ dev_state->name,
+ (unsigned long long)dev_bytenr);
+
+ ret = btrfsic_map_block(state, bytenr, len, &block_ctx,
+ 0);
+ if (ret) {
+ printk(KERN_INFO
+ "btrfsic: btrfsic_map_block(root @%llu)"
+ " failed!\n",
+ (unsigned long long)dev_bytenr);
+ return;
+ }
+ }
+ block_ctx.data = mapped_data;
+ /* the following is required in case of writes to mirrors,
+ * use the same that was used for the lookup */
+ block_ctx.dev = dev_state;
+ block_ctx.dev_bytenr = dev_bytenr;
+
+ block = btrfsic_block_alloc();
+ if (NULL == block) {
+ printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
+ btrfsic_release_block_ctx(&block_ctx);
+ return;
+ }
+ block->dev_state = dev_state;
+ block->dev_bytenr = dev_bytenr;
+ block->logical_bytenr = bytenr;
+ block->is_metadata = is_metadata;
+ block->never_written = 0;
+ block->iodone_w_error = 0;
+ block->mirror_num = 0; /* unknown */
+ block->flush_gen = dev_state->last_flush_gen + 1;
+ block->submit_bio_bh_rw = submit_bio_bh_rw;
+ if (NULL != bio) {
+ block->is_iodone = 0;
+ BUG_ON(NULL == bio_is_patched);
+ if (!*bio_is_patched) {
+ block->orig_bio_bh_private = bio->bi_private;
+ block->orig_bio_bh_end_io.bio = bio->bi_end_io;
+ block->next_in_same_bio = NULL;
+ bio->bi_private = block;
+ bio->bi_end_io = btrfsic_bio_end_io;
+ *bio_is_patched = 1;
+ } else {
+ struct btrfsic_block *chained_block =
+ (struct btrfsic_block *)
+ bio->bi_private;
+
+ BUG_ON(NULL == chained_block);
+ block->orig_bio_bh_private =
+ chained_block->orig_bio_bh_private;
+ block->orig_bio_bh_end_io.bio =
+ chained_block->orig_bio_bh_end_io.bio;
+ block->next_in_same_bio = chained_block;
+ bio->bi_private = block;
+ }
+ } else if (NULL != bh) {
+ block->is_iodone = 0;
+ block->orig_bio_bh_private = bh->b_private;
+ block->orig_bio_bh_end_io.bh = bh->b_end_io;
+ block->next_in_same_bio = NULL;
+ bh->b_private = block;
+ bh->b_end_io = btrfsic_bh_end_io;
+ } else {
+ block->is_iodone = 1;
+ block->orig_bio_bh_private = NULL;
+ block->orig_bio_bh_end_io.bio = NULL;
+ block->next_in_same_bio = NULL;
+ }
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO
+ "New written %c-block @%llu (%s/%llu/%d)\n",
+ is_metadata ? 'M' : 'D',
+ (unsigned long long)block->logical_bytenr,
+ block->dev_state->name,
+ (unsigned long long)block->dev_bytenr,
+ block->mirror_num);
+ list_add(&block->all_blocks_node, &state->all_blocks_list);
+ btrfsic_block_hashtable_add(block, &state->block_hashtable);
+
+ if (is_metadata) {
+ ret = btrfsic_process_metablock(state, block,
+ &block_ctx,
+ (struct btrfs_header *)
+ block_ctx.data, 0, 0);
+ if (ret)
+ printk(KERN_INFO
+ "btrfsic: process_metablock(root @%llu)"
+ " failed!\n",
+ (unsigned long long)dev_bytenr);
+ }
+ btrfsic_release_block_ctx(&block_ctx);
+ }
+}
+
+static void btrfsic_bio_end_io(struct bio *bp, int bio_error_status)
+{
+ struct btrfsic_block *block = (struct btrfsic_block *)bp->bi_private;
+ int iodone_w_error;
+
+ /* mutex is not held! This is not save if IO is not yet completed
+ * on umount */
+ iodone_w_error = 0;
+ if (bio_error_status)
+ iodone_w_error = 1;
+
+ BUG_ON(NULL == block);
+ bp->bi_private = block->orig_bio_bh_private;
+ bp->bi_end_io = block->orig_bio_bh_end_io.bio;
+
+ do {
+ struct btrfsic_block *next_block;
+ struct btrfsic_dev_state *const dev_state = block->dev_state;
+
+ if ((dev_state->state->print_mask &
+ BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
+ printk(KERN_INFO
+ "bio_end_io(err=%d) for %c @%llu (%s/%llu/%d)\n",
+ bio_error_status,
+ btrfsic_get_block_type(dev_state->state, block),
+ (unsigned long long)block->logical_bytenr,
+ dev_state->name,
+ (unsigned long long)block->dev_bytenr,
+ block->mirror_num);
+ next_block = block->next_in_same_bio;
+ block->iodone_w_error = iodone_w_error;
+ if (block->submit_bio_bh_rw & REQ_FLUSH) {
+ dev_state->last_flush_gen++;
+ if ((dev_state->state->print_mask &
+ BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
+ printk(KERN_INFO
+ "bio_end_io() new %s flush_gen=%llu\n",
+ dev_state->name,
+ (unsigned long long)
+ dev_state->last_flush_gen);
+ }
+ if (block->submit_bio_bh_rw & REQ_FUA)
+ block->flush_gen = 0; /* FUA completed means block is
+ * on disk */
+ block->is_iodone = 1; /* for FLUSH, this releases the block */
+ block = next_block;
+ } while (NULL != block);
+
+ bp->bi_end_io(bp, bio_error_status);
+}
+
+static void btrfsic_bh_end_io(struct buffer_head *bh, int uptodate)
+{
+ struct btrfsic_block *block = (struct btrfsic_block *)bh->b_private;
+ int iodone_w_error = !uptodate;
+ struct btrfsic_dev_state *dev_state;
+
+ BUG_ON(NULL == block);
+ dev_state = block->dev_state;
+ if ((dev_state->state->print_mask & BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
+ printk(KERN_INFO
+ "bh_end_io(error=%d) for %c @%llu (%s/%llu/%d)\n",
+ iodone_w_error,
+ btrfsic_get_block_type(dev_state->state, block),
+ (unsigned long long)block->logical_bytenr,
+ block->dev_state->name,
+ (unsigned long long)block->dev_bytenr,
+ block->mirror_num);
+
+ block->iodone_w_error = iodone_w_error;
+ if (block->submit_bio_bh_rw & REQ_FLUSH) {
+ dev_state->last_flush_gen++;
+ if ((dev_state->state->print_mask &
+ BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
+ printk(KERN_INFO
+ "bh_end_io() new %s flush_gen=%llu\n",
+ dev_state->name,
+ (unsigned long long)dev_state->last_flush_gen);
+ }
+ if (block->submit_bio_bh_rw & REQ_FUA)
+ block->flush_gen = 0; /* FUA completed means block is on disk */
+
+ bh->b_private = block->orig_bio_bh_private;
+ bh->b_end_io = block->orig_bio_bh_end_io.bh;
+ block->is_iodone = 1; /* for FLUSH, this releases the block */
+ bh->b_end_io(bh, uptodate);
+}
+
+static int btrfsic_process_written_superblock(
+ struct btrfsic_state *state,
+ struct btrfsic_block *const superblock,
+ struct btrfs_super_block *const super_hdr)
+{
+ int pass;
+
+ superblock->generation = btrfs_super_generation(super_hdr);
+ if (!(superblock->generation > state->max_superblock_generation ||
+ 0 == state->max_superblock_generation)) {
+ if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
+ printk(KERN_INFO
+ "btrfsic: superblock @%llu (%s/%llu/%d)"
+ " with old gen %llu <= %llu\n",
+ (unsigned long long)superblock->logical_bytenr,
+ superblock->dev_state->name,
+ (unsigned long long)superblock->dev_bytenr,
+ superblock->mirror_num,
+ (unsigned long long)
+ btrfs_super_generation(super_hdr),
+ (unsigned long long)
+ state->max_superblock_generation);
+ } else {
+ if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
+ printk(KERN_INFO
+ "btrfsic: got new superblock @%llu (%s/%llu/%d)"
+ " with new gen %llu > %llu\n",
+ (unsigned long long)superblock->logical_bytenr,
+ superblock->dev_state->name,
+ (unsigned long long)superblock->dev_bytenr,
+ superblock->mirror_num,
+ (unsigned long long)
+ btrfs_super_generation(super_hdr),
+ (unsigned long long)
+ state->max_superblock_generation);
+
+ state->max_superblock_generation =
+ btrfs_super_generation(super_hdr);
+ state->latest_superblock = superblock;
+ }
+
+ for (pass = 0; pass < 3; pass++) {
+ int ret;
+ u64 next_bytenr;
+ struct btrfsic_block *next_block;
+ struct btrfsic_block_data_ctx tmp_next_block_ctx;
+ struct btrfsic_block_link *l;
+ int num_copies;
+ int mirror_num;
+ const char *additional_string = NULL;
+ struct btrfs_disk_key tmp_disk_key;
+
+ tmp_disk_key.type = BTRFS_ROOT_ITEM_KEY;
+ tmp_disk_key.offset = 0;
+
+ switch (pass) {
+ case 0:
+ tmp_disk_key.objectid =
+ cpu_to_le64(BTRFS_ROOT_TREE_OBJECTID);
+ additional_string = "root ";
+ next_bytenr = btrfs_super_root(super_hdr);
+ if (state->print_mask &
+ BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
+ printk(KERN_INFO "root@%llu\n",
+ (unsigned long long)next_bytenr);
+ break;
+ case 1:
+ tmp_disk_key.objectid =
+ cpu_to_le64(BTRFS_CHUNK_TREE_OBJECTID);
+ additional_string = "chunk ";
+ next_bytenr = btrfs_super_chunk_root(super_hdr);
+ if (state->print_mask &
+ BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
+ printk(KERN_INFO "chunk@%llu\n",
+ (unsigned long long)next_bytenr);
+ break;
+ case 2:
+ tmp_disk_key.objectid =
+ cpu_to_le64(BTRFS_TREE_LOG_OBJECTID);
+ additional_string = "log ";
+ next_bytenr = btrfs_super_log_root(super_hdr);
+ if (0 == next_bytenr)
+ continue;
+ if (state->print_mask &
+ BTRFSIC_PRINT_MASK_ROOT_CHUNK_LOG_TREE_LOCATION)
+ printk(KERN_INFO "log@%llu\n",
+ (unsigned long long)next_bytenr);
+ break;
+ }
+
+ num_copies =
+ btrfs_num_copies(&state->root->fs_info->mapping_tree,
+ next_bytenr, PAGE_SIZE);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
+ printk(KERN_INFO "num_copies(log_bytenr=%llu) = %d\n",
+ (unsigned long long)next_bytenr, num_copies);
+ for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
+ int was_created;
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO
+ "btrfsic_process_written_superblock("
+ "mirror_num=%d)\n", mirror_num);
+ ret = btrfsic_map_block(state, next_bytenr, PAGE_SIZE,
+ &tmp_next_block_ctx,
+ mirror_num);
+ if (ret) {
+ printk(KERN_INFO
+ "btrfsic: btrfsic_map_block(@%llu,"
+ " mirror=%d) failed!\n",
+ (unsigned long long)next_bytenr,
+ mirror_num);
+ return -1;
+ }
+
+ next_block = btrfsic_block_lookup_or_add(
+ state,
+ &tmp_next_block_ctx,
+ additional_string,
+ 1, 0, 1,
+ mirror_num,
+ &was_created);
+ if (NULL == next_block) {
+ printk(KERN_INFO
+ "btrfsic: error, kmalloc failed!\n");
+ btrfsic_release_block_ctx(&tmp_next_block_ctx);
+ return -1;
+ }
+
+ next_block->disk_key = tmp_disk_key;
+ if (was_created)
+ next_block->generation =
+ BTRFSIC_GENERATION_UNKNOWN;
+ l = btrfsic_block_link_lookup_or_add(
+ state,
+ &tmp_next_block_ctx,
+ next_block,
+ superblock,
+ BTRFSIC_GENERATION_UNKNOWN);
+ btrfsic_release_block_ctx(&tmp_next_block_ctx);
+ if (NULL == l)
+ return -1;
+ }
+ }
+
+ if (-1 == btrfsic_check_all_ref_blocks(state, superblock, 0)) {
+ WARN_ON(1);
+ btrfsic_dump_tree(state);
+ }
+
+ return 0;
+}
+
+static int btrfsic_check_all_ref_blocks(struct btrfsic_state *state,
+ struct btrfsic_block *const block,
+ int recursion_level)
+{
+ struct list_head *elem_ref_to;
+ int ret = 0;
+
+ if (recursion_level >= 3 + BTRFS_MAX_LEVEL) {
+ /*
+ * Note that this situation can happen and does not
+ * indicate an error in regular cases. It happens
+ * when disk blocks are freed and later reused.
+ * The check-integrity module is not aware of any
+ * block free operations, it just recognizes block
+ * write operations. Therefore it keeps the linkage
+ * information for a block until a block is
+ * rewritten. This can temporarily cause incorrect
+ * and even circular linkage informations. This
+ * causes no harm unless such blocks are referenced
+ * by the most recent super block.
+ */
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO
+ "btrfsic: abort cyclic linkage (case 1).\n");
+
+ return ret;
+ }
+
+ /*
+ * This algorithm is recursive because the amount of used stack
+ * space is very small and the max recursion depth is limited.
+ */
+ list_for_each(elem_ref_to, &block->ref_to_list) {
+ const struct btrfsic_block_link *const l =
+ list_entry(elem_ref_to, struct btrfsic_block_link,
+ node_ref_to);
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO
+ "rl=%d, %c @%llu (%s/%llu/%d)"
+ " %u* refers to %c @%llu (%s/%llu/%d)\n",
+ recursion_level,
+ btrfsic_get_block_type(state, block),
+ (unsigned long long)block->logical_bytenr,
+ block->dev_state->name,
+ (unsigned long long)block->dev_bytenr,
+ block->mirror_num,
+ l->ref_cnt,
+ btrfsic_get_block_type(state, l->block_ref_to),
+ (unsigned long long)
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->name,
+ (unsigned long long)l->block_ref_to->dev_bytenr,
+ l->block_ref_to->mirror_num);
+ if (l->block_ref_to->never_written) {
+ printk(KERN_INFO "btrfs: attempt to write superblock"
+ " which references block %c @%llu (%s/%llu/%d)"
+ " which is never written!\n",
+ btrfsic_get_block_type(state, l->block_ref_to),
+ (unsigned long long)
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->name,
+ (unsigned long long)l->block_ref_to->dev_bytenr,
+ l->block_ref_to->mirror_num);
+ ret = -1;
+ } else if (!l->block_ref_to->is_iodone) {
+ printk(KERN_INFO "btrfs: attempt to write superblock"
+ " which references block %c @%llu (%s/%llu/%d)"
+ " which is not yet iodone!\n",
+ btrfsic_get_block_type(state, l->block_ref_to),
+ (unsigned long long)
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->name,
+ (unsigned long long)l->block_ref_to->dev_bytenr,
+ l->block_ref_to->mirror_num);
+ ret = -1;
+ } else if (l->parent_generation !=
+ l->block_ref_to->generation &&
+ BTRFSIC_GENERATION_UNKNOWN !=
+ l->parent_generation &&
+ BTRFSIC_GENERATION_UNKNOWN !=
+ l->block_ref_to->generation) {
+ printk(KERN_INFO "btrfs: attempt to write superblock"
+ " which references block %c @%llu (%s/%llu/%d)"
+ " with generation %llu !="
+ " parent generation %llu!\n",
+ btrfsic_get_block_type(state, l->block_ref_to),
+ (unsigned long long)
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->name,
+ (unsigned long long)l->block_ref_to->dev_bytenr,
+ l->block_ref_to->mirror_num,
+ (unsigned long long)l->block_ref_to->generation,
+ (unsigned long long)l->parent_generation);
+ ret = -1;
+ } else if (l->block_ref_to->flush_gen >
+ l->block_ref_to->dev_state->last_flush_gen) {
+ printk(KERN_INFO "btrfs: attempt to write superblock"
+ " which references block %c @%llu (%s/%llu/%d)"
+ " which is not flushed out of disk's write cache"
+ " (block flush_gen=%llu,"
+ " dev->flush_gen=%llu)!\n",
+ btrfsic_get_block_type(state, l->block_ref_to),
+ (unsigned long long)
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->name,
+ (unsigned long long)l->block_ref_to->dev_bytenr,
+ l->block_ref_to->mirror_num,
+ (unsigned long long)block->flush_gen,
+ (unsigned long long)
+ l->block_ref_to->dev_state->last_flush_gen);
+ ret = -1;
+ } else if (-1 == btrfsic_check_all_ref_blocks(state,
+ l->block_ref_to,
+ recursion_level +
+ 1)) {
+ ret = -1;
+ }
+ }
+
+ return ret;
+}
+
+static int btrfsic_is_block_ref_by_superblock(
+ const struct btrfsic_state *state,
+ const struct btrfsic_block *block,
+ int recursion_level)
+{
+ struct list_head *elem_ref_from;
+
+ if (recursion_level >= 3 + BTRFS_MAX_LEVEL) {
+ /* refer to comment at "abort cyclic linkage (case 1)" */
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO
+ "btrfsic: abort cyclic linkage (case 2).\n");
+
+ return 0;
+ }
+
+ /*
+ * This algorithm is recursive because the amount of used stack space
+ * is very small and the max recursion depth is limited.
+ */
+ list_for_each(elem_ref_from, &block->ref_from_list) {
+ const struct btrfsic_block_link *const l =
+ list_entry(elem_ref_from, struct btrfsic_block_link,
+ node_ref_from);
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO
+ "rl=%d, %c @%llu (%s/%llu/%d)"
+ " is ref %u* from %c @%llu (%s/%llu/%d)\n",
+ recursion_level,
+ btrfsic_get_block_type(state, block),
+ (unsigned long long)block->logical_bytenr,
+ block->dev_state->name,
+ (unsigned long long)block->dev_bytenr,
+ block->mirror_num,
+ l->ref_cnt,
+ btrfsic_get_block_type(state, l->block_ref_from),
+ (unsigned long long)
+ l->block_ref_from->logical_bytenr,
+ l->block_ref_from->dev_state->name,
+ (unsigned long long)
+ l->block_ref_from->dev_bytenr,
+ l->block_ref_from->mirror_num);
+ if (l->block_ref_from->is_superblock &&
+ state->latest_superblock->dev_bytenr ==
+ l->block_ref_from->dev_bytenr &&
+ state->latest_superblock->dev_state->bdev ==
+ l->block_ref_from->dev_state->bdev)
+ return 1;
+ else if (btrfsic_is_block_ref_by_superblock(state,
+ l->block_ref_from,
+ recursion_level +
+ 1))
+ return 1;
+ }
+
+ return 0;
+}
+
+static void btrfsic_print_add_link(const struct btrfsic_state *state,
+ const struct btrfsic_block_link *l)
+{
+ printk(KERN_INFO
+ "Add %u* link from %c @%llu (%s/%llu/%d)"
+ " to %c @%llu (%s/%llu/%d).\n",
+ l->ref_cnt,
+ btrfsic_get_block_type(state, l->block_ref_from),
+ (unsigned long long)l->block_ref_from->logical_bytenr,
+ l->block_ref_from->dev_state->name,
+ (unsigned long long)l->block_ref_from->dev_bytenr,
+ l->block_ref_from->mirror_num,
+ btrfsic_get_block_type(state, l->block_ref_to),
+ (unsigned long long)l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->name,
+ (unsigned long long)l->block_ref_to->dev_bytenr,
+ l->block_ref_to->mirror_num);
+}
+
+static void btrfsic_print_rem_link(const struct btrfsic_state *state,
+ const struct btrfsic_block_link *l)
+{
+ printk(KERN_INFO
+ "Rem %u* link from %c @%llu (%s/%llu/%d)"
+ " to %c @%llu (%s/%llu/%d).\n",
+ l->ref_cnt,
+ btrfsic_get_block_type(state, l->block_ref_from),
+ (unsigned long long)l->block_ref_from->logical_bytenr,
+ l->block_ref_from->dev_state->name,
+ (unsigned long long)l->block_ref_from->dev_bytenr,
+ l->block_ref_from->mirror_num,
+ btrfsic_get_block_type(state, l->block_ref_to),
+ (unsigned long long)l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->name,
+ (unsigned long long)l->block_ref_to->dev_bytenr,
+ l->block_ref_to->mirror_num);
+}
+
+static char btrfsic_get_block_type(const struct btrfsic_state *state,
+ const struct btrfsic_block *block)
+{
+ if (block->is_superblock &&
+ state->latest_superblock->dev_bytenr == block->dev_bytenr &&
+ state->latest_superblock->dev_state->bdev == block->dev_state->bdev)
+ return 'S';
+ else if (block->is_superblock)
+ return 's';
+ else if (block->is_metadata)
+ return 'M';
+ else
+ return 'D';
+}
+
+static void btrfsic_dump_tree(const struct btrfsic_state *state)
+{
+ btrfsic_dump_tree_sub(state, state->latest_superblock, 0);
+}
+
+static void btrfsic_dump_tree_sub(const struct btrfsic_state *state,
+ const struct btrfsic_block *block,
+ int indent_level)
+{
+ struct list_head *elem_ref_to;
+ int indent_add;
+ static char buf[80];
+ int cursor_position;
+
+ /*
+ * Should better fill an on-stack buffer with a complete line and
+ * dump it at once when it is time to print a newline character.
+ */
+
+ /*
+ * This algorithm is recursive because the amount of used stack space
+ * is very small and the max recursion depth is limited.
+ */
+ indent_add = sprintf(buf, "%c-%llu(%s/%llu/%d)",
+ btrfsic_get_block_type(state, block),
+ (unsigned long long)block->logical_bytenr,
+ block->dev_state->name,
+ (unsigned long long)block->dev_bytenr,
+ block->mirror_num);
+ if (indent_level + indent_add > BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) {
+ printk("[...]\n");
+ return;
+ }
+ printk(buf);
+ indent_level += indent_add;
+ if (list_empty(&block->ref_to_list)) {
+ printk("\n");
+ return;
+ }
+ if (block->mirror_num > 1 &&
+ !(state->print_mask & BTRFSIC_PRINT_MASK_TREE_WITH_ALL_MIRRORS)) {
+ printk(" [...]\n");
+ return;
+ }
+
+ cursor_position = indent_level;
+ list_for_each(elem_ref_to, &block->ref_to_list) {
+ const struct btrfsic_block_link *const l =
+ list_entry(elem_ref_to, struct btrfsic_block_link,
+ node_ref_to);
+
+ while (cursor_position < indent_level) {
+ printk(" ");
+ cursor_position++;
+ }
+ if (l->ref_cnt > 1)
+ indent_add = sprintf(buf, " %d*--> ", l->ref_cnt);
+ else
+ indent_add = sprintf(buf, " --> ");
+ if (indent_level + indent_add >
+ BTRFSIC_TREE_DUMP_MAX_INDENT_LEVEL) {
+ printk("[...]\n");
+ cursor_position = 0;
+ continue;
+ }
+
+ printk(buf);
+
+ btrfsic_dump_tree_sub(state, l->block_ref_to,
+ indent_level + indent_add);
+ cursor_position = 0;
+ }
+}
+
+static struct btrfsic_block_link *btrfsic_block_link_lookup_or_add(
+ struct btrfsic_state *state,
+ struct btrfsic_block_data_ctx *next_block_ctx,
+ struct btrfsic_block *next_block,
+ struct btrfsic_block *from_block,
+ u64 parent_generation)
+{
+ struct btrfsic_block_link *l;
+
+ l = btrfsic_block_link_hashtable_lookup(next_block_ctx->dev->bdev,
+ next_block_ctx->dev_bytenr,
+ from_block->dev_state->bdev,
+ from_block->dev_bytenr,
+ &state->block_link_hashtable);
+ if (NULL == l) {
+ l = btrfsic_block_link_alloc();
+ if (NULL == l) {
+ printk(KERN_INFO
+ "btrfsic: error, kmalloc" " failed!\n");
+ return NULL;
+ }
+
+ l->block_ref_to = next_block;
+ l->block_ref_from = from_block;
+ l->ref_cnt = 1;
+ l->parent_generation = parent_generation;
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ btrfsic_print_add_link(state, l);
+
+ list_add(&l->node_ref_to, &from_block->ref_to_list);
+ list_add(&l->node_ref_from, &next_block->ref_from_list);
+
+ btrfsic_block_link_hashtable_add(l,
+ &state->block_link_hashtable);
+ } else {
+ l->ref_cnt++;
+ l->parent_generation = parent_generation;
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ btrfsic_print_add_link(state, l);
+ }
+
+ return l;
+}
+
+static struct btrfsic_block *btrfsic_block_lookup_or_add(
+ struct btrfsic_state *state,
+ struct btrfsic_block_data_ctx *block_ctx,
+ const char *additional_string,
+ int is_metadata,
+ int is_iodone,
+ int never_written,
+ int mirror_num,
+ int *was_created)
+{
+ struct btrfsic_block *block;
+
+ block = btrfsic_block_hashtable_lookup(block_ctx->dev->bdev,
+ block_ctx->dev_bytenr,
+ &state->block_hashtable);
+ if (NULL == block) {
+ struct btrfsic_dev_state *dev_state;
+
+ block = btrfsic_block_alloc();
+ if (NULL == block) {
+ printk(KERN_INFO "btrfsic: error, kmalloc failed!\n");
+ return NULL;
+ }
+ dev_state = btrfsic_dev_state_lookup(block_ctx->dev->bdev);
+ if (NULL == dev_state) {
+ printk(KERN_INFO
+ "btrfsic: error, lookup dev_state failed!\n");
+ btrfsic_block_free(block);
+ return NULL;
+ }
+ block->dev_state = dev_state;
+ block->dev_bytenr = block_ctx->dev_bytenr;
+ block->logical_bytenr = block_ctx->start;
+ block->is_metadata = is_metadata;
+ block->is_iodone = is_iodone;
+ block->never_written = never_written;
+ block->mirror_num = mirror_num;
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ printk(KERN_INFO
+ "New %s%c-block @%llu (%s/%llu/%d)\n",
+ additional_string,
+ btrfsic_get_block_type(state, block),
+ (unsigned long long)block->logical_bytenr,
+ dev_state->name,
+ (unsigned long long)block->dev_bytenr,
+ mirror_num);
+ list_add(&block->all_blocks_node, &state->all_blocks_list);
+ btrfsic_block_hashtable_add(block, &state->block_hashtable);
+ if (NULL != was_created)
+ *was_created = 1;
+ } else {
+ if (NULL != was_created)
+ *was_created = 0;
+ }
+
+ return block;
+}
+
+static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state,
+ u64 bytenr,
+ struct btrfsic_dev_state *dev_state,
+ u64 dev_bytenr, char *data)
+{
+ int num_copies;
+ int mirror_num;
+ int ret;
+ struct btrfsic_block_data_ctx block_ctx;
+ int match = 0;
+
+ num_copies = btrfs_num_copies(&state->root->fs_info->mapping_tree,
+ bytenr, PAGE_SIZE);
+
+ for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
+ ret = btrfsic_map_block(state, bytenr, PAGE_SIZE,
+ &block_ctx, mirror_num);
+ if (ret) {
+ printk(KERN_INFO "btrfsic:"
+ " btrfsic_map_block(logical @%llu,"
+ " mirror %d) failed!\n",
+ (unsigned long long)bytenr, mirror_num);
+ continue;
+ }
+
+ if (dev_state->bdev == block_ctx.dev->bdev &&
+ dev_bytenr == block_ctx.dev_bytenr) {
+ match++;
+ btrfsic_release_block_ctx(&block_ctx);
+ break;
+ }
+ btrfsic_release_block_ctx(&block_ctx);
+ }
+
+ if (!match) {
+ printk(KERN_INFO "btrfs: attempt to write M-block which contains logical bytenr that doesn't map to dev+physical bytenr of submit_bio,"
+ " buffer->log_bytenr=%llu, submit_bio(bdev=%s,"
+ " phys_bytenr=%llu)!\n",
+ (unsigned long long)bytenr, dev_state->name,
+ (unsigned long long)dev_bytenr);
+ for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
+ ret = btrfsic_map_block(state, bytenr, PAGE_SIZE,
+ &block_ctx, mirror_num);
+ if (ret)
+ continue;
+
+ printk(KERN_INFO "Read logical bytenr @%llu maps to"
+ " (%s/%llu/%d)\n",
+ (unsigned long long)bytenr,
+ block_ctx.dev->name,
+ (unsigned long long)block_ctx.dev_bytenr,
+ mirror_num);
+ }
+ WARN_ON(1);
+ }
+}
+
+static struct btrfsic_dev_state *btrfsic_dev_state_lookup(
+ struct block_device *bdev)
+{
+ struct btrfsic_dev_state *ds;
+
+ ds = btrfsic_dev_state_hashtable_lookup(bdev,
+ &btrfsic_dev_state_hashtable);
+ return ds;
+}
+
+int btrfsic_submit_bh(int rw, struct buffer_head *bh)
+{
+ struct btrfsic_dev_state *dev_state;
+
+ if (!btrfsic_is_initialized)
+ return submit_bh(rw, bh);
+
+ mutex_lock(&btrfsic_mutex);
+ /* since btrfsic_submit_bh() might also be called before
+ * btrfsic_mount(), this might return NULL */
+ dev_state = btrfsic_dev_state_lookup(bh->b_bdev);
+
+ /* Only called to write the superblock (incl. FLUSH/FUA) */
+ if (NULL != dev_state &&
+ (rw & WRITE) && bh->b_size > 0) {
+ u64 dev_bytenr;
+
+ dev_bytenr = 4096 * bh->b_blocknr;
+ if (dev_state->state->print_mask &
+ BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
+ printk(KERN_INFO
+ "submit_bh(rw=0x%x, blocknr=%lu (bytenr %llu),"
+ " size=%lu, data=%p, bdev=%p)\n",
+ rw, bh->b_blocknr,
+ (unsigned long long)dev_bytenr, bh->b_size,
+ bh->b_data, bh->b_bdev);
+ btrfsic_process_written_block(dev_state, dev_bytenr,
+ bh->b_data, bh->b_size, NULL,
+ NULL, bh, rw);
+ } else if (NULL != dev_state && (rw & REQ_FLUSH)) {
+ if (dev_state->state->print_mask &
+ BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
+ printk(KERN_INFO
+ "submit_bh(rw=0x%x) FLUSH, bdev=%p)\n",
+ rw, bh->b_bdev);
+ if (!dev_state->dummy_block_for_bio_bh_flush.is_iodone) {
+ if ((dev_state->state->print_mask &
+ (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH |
+ BTRFSIC_PRINT_MASK_VERBOSE)))
+ printk(KERN_INFO
+ "btrfsic_submit_bh(%s) with FLUSH"
+ " but dummy block already in use"
+ " (ignored)!\n",
+ dev_state->name);
+ } else {
+ struct btrfsic_block *const block =
+ &dev_state->dummy_block_for_bio_bh_flush;
+
+ block->is_iodone = 0;
+ block->never_written = 0;
+ block->iodone_w_error = 0;
+ block->flush_gen = dev_state->last_flush_gen + 1;
+ block->submit_bio_bh_rw = rw;
+ block->orig_bio_bh_private = bh->b_private;
+ block->orig_bio_bh_end_io.bh = bh->b_end_io;
+ block->next_in_same_bio = NULL;
+ bh->b_private = block;
+ bh->b_end_io = btrfsic_bh_end_io;
+ }
+ }
+ mutex_unlock(&btrfsic_mutex);
+ return submit_bh(rw, bh);
+}
+
+void btrfsic_submit_bio(int rw, struct bio *bio)
+{
+ struct btrfsic_dev_state *dev_state;
+
+ if (!btrfsic_is_initialized) {
+ submit_bio(rw, bio);
+ return;
+ }
+
+ mutex_lock(&btrfsic_mutex);
+ /* since btrfsic_submit_bio() is also called before
+ * btrfsic_mount(), this might return NULL */
+ dev_state = btrfsic_dev_state_lookup(bio->bi_bdev);
+ if (NULL != dev_state &&
+ (rw & WRITE) && NULL != bio->bi_io_vec) {
+ unsigned int i;
+ u64 dev_bytenr;
+ int bio_is_patched;
+
+ dev_bytenr = 512 * bio->bi_sector;
+ bio_is_patched = 0;
+ if (dev_state->state->print_mask &
+ BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
+ printk(KERN_INFO
+ "submit_bio(rw=0x%x, bi_vcnt=%u,"
+ " bi_sector=%lu (bytenr %llu), bi_bdev=%p)\n",
+ rw, bio->bi_vcnt, bio->bi_sector,
+ (unsigned long long)dev_bytenr,
+ bio->bi_bdev);
+
+ for (i = 0; i < bio->bi_vcnt; i++) {
+ u8 *mapped_data;
+
+ mapped_data = kmap(bio->bi_io_vec[i].bv_page);
+ if ((BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH |
+ BTRFSIC_PRINT_MASK_VERBOSE) ==
+ (dev_state->state->print_mask &
+ (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH |
+ BTRFSIC_PRINT_MASK_VERBOSE)))
+ printk(KERN_INFO
+ "#%u: page=%p, mapped=%p, len=%u,"
+ " offset=%u\n",
+ i, bio->bi_io_vec[i].bv_page,
+ mapped_data,
+ bio->bi_io_vec[i].bv_len,
+ bio->bi_io_vec[i].bv_offset);
+ btrfsic_process_written_block(dev_state, dev_bytenr,
+ mapped_data,
+ bio->bi_io_vec[i].bv_len,
+ bio, &bio_is_patched,
+ NULL, rw);
+ kunmap(bio->bi_io_vec[i].bv_page);
+ dev_bytenr += bio->bi_io_vec[i].bv_len;
+ }
+ } else if (NULL != dev_state && (rw & REQ_FLUSH)) {
+ if (dev_state->state->print_mask &
+ BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
+ printk(KERN_INFO
+ "submit_bio(rw=0x%x) FLUSH, bdev=%p)\n",
+ rw, bio->bi_bdev);
+ if (!dev_state->dummy_block_for_bio_bh_flush.is_iodone) {
+ if ((dev_state->state->print_mask &
+ (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH |
+ BTRFSIC_PRINT_MASK_VERBOSE)))
+ printk(KERN_INFO
+ "btrfsic_submit_bio(%s) with FLUSH"
+ " but dummy block already in use"
+ " (ignored)!\n",
+ dev_state->name);
+ } else {
+ struct btrfsic_block *const block =
+ &dev_state->dummy_block_for_bio_bh_flush;
+
+ block->is_iodone = 0;
+ block->never_written = 0;
+ block->iodone_w_error = 0;
+ block->flush_gen = dev_state->last_flush_gen + 1;
+ block->submit_bio_bh_rw = rw;
+ block->orig_bio_bh_private = bio->bi_private;
+ block->orig_bio_bh_end_io.bio = bio->bi_end_io;
+ block->next_in_same_bio = NULL;
+ bio->bi_private = block;
+ bio->bi_end_io = btrfsic_bio_end_io;
+ }
+ }
+ mutex_unlock(&btrfsic_mutex);
+
+ submit_bio(rw, bio);
+}
+
+int btrfsic_mount(struct btrfs_root *root,
+ struct btrfs_fs_devices *fs_devices,
+ int including_extent_data, u32 print_mask)
+{
+ int ret;
+ struct btrfsic_state *state;
+ struct list_head *dev_head = &fs_devices->devices;
+ struct btrfs_device *device;
+
+ state = kzalloc(sizeof(*state), GFP_NOFS);
+ if (NULL == state) {
+ printk(KERN_INFO "btrfs check-integrity: kmalloc() failed!\n");
+ return -1;
+ }
+
+ if (!btrfsic_is_initialized) {
+ mutex_init(&btrfsic_mutex);
+ btrfsic_dev_state_hashtable_init(&btrfsic_dev_state_hashtable);
+ btrfsic_is_initialized = 1;
+ }
+ mutex_lock(&btrfsic_mutex);
+ state->root = root;
+ state->print_mask = print_mask;
+ state->include_extent_data = including_extent_data;
+ state->csum_size = 0;
+ INIT_LIST_HEAD(&state->all_blocks_list);
+ btrfsic_block_hashtable_init(&state->block_hashtable);
+ btrfsic_block_link_hashtable_init(&state->block_link_hashtable);
+ state->max_superblock_generation = 0;
+ state->latest_superblock = NULL;
+
+ list_for_each_entry(device, dev_head, dev_list) {
+ struct btrfsic_dev_state *ds;
+ char *p;
+
+ if (!device->bdev || !device->name)
+ continue;
+
+ ds = btrfsic_dev_state_alloc();
+ if (NULL == ds) {
+ printk(KERN_INFO
+ "btrfs check-integrity: kmalloc() failed!\n");
+ mutex_unlock(&btrfsic_mutex);
+ return -1;
+ }
+ ds->bdev = device->bdev;
+ ds->state = state;
+ bdevname(ds->bdev, ds->name);
+ ds->name[BDEVNAME_SIZE - 1] = '\0';
+ for (p = ds->name; *p != '\0'; p++);
+ while (p > ds->name && *p != '/')
+ p--;
+ if (*p == '/')
+ p++;
+ strlcpy(ds->name, p, sizeof(ds->name));
+ btrfsic_dev_state_hashtable_add(ds,
+ &btrfsic_dev_state_hashtable);
+ }
+
+ ret = btrfsic_process_superblock(state, fs_devices);
+ if (0 != ret) {
+ mutex_unlock(&btrfsic_mutex);
+ btrfsic_unmount(root, fs_devices);
+ return ret;
+ }
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_DATABASE)
+ btrfsic_dump_database(state);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_TREE)
+ btrfsic_dump_tree(state);
+
+ mutex_unlock(&btrfsic_mutex);
+ return 0;
+}
+
+void btrfsic_unmount(struct btrfs_root *root,
+ struct btrfs_fs_devices *fs_devices)
+{
+ struct list_head *elem_all;
+ struct list_head *tmp_all;
+ struct btrfsic_state *state;
+ struct list_head *dev_head = &fs_devices->devices;
+ struct btrfs_device *device;
+
+ if (!btrfsic_is_initialized)
+ return;
+
+ mutex_lock(&btrfsic_mutex);
+
+ state = NULL;
+ list_for_each_entry(device, dev_head, dev_list) {
+ struct btrfsic_dev_state *ds;
+
+ if (!device->bdev || !device->name)
+ continue;
+
+ ds = btrfsic_dev_state_hashtable_lookup(
+ device->bdev,
+ &btrfsic_dev_state_hashtable);
+ if (NULL != ds) {
+ state = ds->state;
+ btrfsic_dev_state_hashtable_remove(ds);
+ btrfsic_dev_state_free(ds);
+ }
+ }
+
+ if (NULL == state) {
+ printk(KERN_INFO
+ "btrfsic: error, cannot find state information"
+ " on umount!\n");
+ mutex_unlock(&btrfsic_mutex);
+ return;
+ }
+
+ /*
+ * Don't care about keeping the lists' state up to date,
+ * just free all memory that was allocated dynamically.
+ * Free the blocks and the block_links.
+ */
+ list_for_each_safe(elem_all, tmp_all, &state->all_blocks_list) {
+ struct btrfsic_block *const b_all =
+ list_entry(elem_all, struct btrfsic_block,
+ all_blocks_node);
+ struct list_head *elem_ref_to;
+ struct list_head *tmp_ref_to;
+
+ list_for_each_safe(elem_ref_to, tmp_ref_to,
+ &b_all->ref_to_list) {
+ struct btrfsic_block_link *const l =
+ list_entry(elem_ref_to,
+ struct btrfsic_block_link,
+ node_ref_to);
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ btrfsic_print_rem_link(state, l);
+
+ l->ref_cnt--;
+ if (0 == l->ref_cnt)
+ btrfsic_block_link_free(l);
+ }
+
+ if (b_all->is_iodone)
+ btrfsic_block_free(b_all);
+ else
+ printk(KERN_INFO "btrfs: attempt to free %c-block"
+ " @%llu (%s/%llu/%d) on umount which is"
+ " not yet iodone!\n",
+ btrfsic_get_block_type(state, b_all),
+ (unsigned long long)b_all->logical_bytenr,
+ b_all->dev_state->name,
+ (unsigned long long)b_all->dev_bytenr,
+ b_all->mirror_num);
+ }
+
+ mutex_unlock(&btrfsic_mutex);
+
+ kfree(state);
+}