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-rw-r--r--fs/btrfs/check-integrity.c2871
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diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c
new file mode 100644
index 0000000000..3caf339c4b
--- /dev/null
+++ b/fs/btrfs/check-integrity.c
@@ -0,0 +1,2871 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STRATO AG 2011. All rights reserved.
+ */
+
+/*
+ * 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 no write error was indicated 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.
+ *
+ * Expect millions of lines of information in the kernel log with an
+ * enabled check_int_print_mask. Therefore set LOG_BUF_SHIFT in the
+ * kernel config to at least 26 (which is 64MB). Usually the value is
+ * limited to 21 (which is 2MB) in init/Kconfig. The file needs to be
+ * changed like this before LOG_BUF_SHIFT can be set to a high value:
+ * config LOG_BUF_SHIFT
+ * int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
+ * range 12 30
+ */
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/blkdev.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <crypto/hash.h>
+#include "messages.h"
+#include "ctree.h"
+#include "disk-io.h"
+#include "transaction.h"
+#include "extent_io.h"
+#include "volumes.h"
+#include "print-tree.h"
+#include "locking.h"
+#include "check-integrity.h"
+#include "rcu-string.h"
+#include "compression.h"
+#include "accessors.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_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
+#define BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE 0x00002000
+
+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; /* 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_private;
+ bio_end_io_t *orig_bio_end_io;
+ blk_opf_t 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 referred 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;
+};
+
+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 **datav;
+ struct page **pagev;
+ void *mem_to_free;
+};
+
+/* 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;
+ struct list_head all_blocks_list;
+ struct btrfsic_block_hashtable block_hashtable;
+ struct btrfsic_block_link_hashtable block_link_hashtable;
+ struct btrfs_fs_info *fs_info;
+ u64 max_superblock_generation;
+ struct btrfsic_block *latest_superblock;
+ u32 metablock_size;
+ u32 datablock_size;
+};
+
+static int btrfsic_process_metablock(struct btrfsic_state *state,
+ struct btrfsic_block *block,
+ struct btrfsic_block_data_ctx *block_ctx,
+ int limit_nesting, int force_iodone_flag);
+static void btrfsic_read_from_block_data(
+ struct btrfsic_block_data_ctx *block_ctx,
+ void *dst, u32 offset, size_t len);
+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 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 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);
+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(dev_t dev);
+static void btrfsic_cmp_log_and_dev_bytenr(struct btrfsic_state *state,
+ u64 bytenr,
+ struct btrfsic_dev_state *dev_state,
+ u64 dev_bytenr);
+
+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_private = NULL;
+ b->orig_bio_end_io = 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;
+ 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 btrfsic_block *b;
+
+ list_for_each_entry(b, h->table + hashval, 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 btrfsic_block_link *l;
+
+ list_for_each_entry(l, h->table + hashval, 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->bd_dev)) &
+ (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(dev_t dev,
+ struct btrfsic_dev_state_hashtable *h)
+{
+ const unsigned int hashval =
+ dev & (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1);
+ struct btrfsic_dev_state *ds;
+
+ list_for_each_entry(ds, h->table + hashval, collision_resolving_node) {
+ if (ds->bdev->bd_dev == dev)
+ return ds;
+ }
+
+ return NULL;
+}
+
+static int btrfsic_process_superblock(struct btrfsic_state *state,
+ struct btrfs_fs_devices *fs_devices)
+{
+ 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 ret = 0;
+ int pass;
+
+ selected_super = kzalloc(sizeof(*selected_super), GFP_NOFS);
+ if (!selected_super)
+ return -ENOMEM;
+
+ 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->bd_dev);
+ 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) {
+ pr_info("btrfsic: no superblock found!\n");
+ kfree(selected_super);
+ return -1;
+ }
+
+ 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)
+ pr_info("root@%llu\n", 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)
+ pr_info("chunk@%llu\n", 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)
+ pr_info("log@%llu\n", next_bytenr);
+ break;
+ }
+
+ num_copies = btrfs_num_copies(state->fs_info, next_bytenr,
+ state->metablock_size);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
+ pr_info("num_copies(log_bytenr=%llu) = %d\n",
+ 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;
+
+ ret = btrfsic_map_block(state, next_bytenr,
+ state->metablock_size,
+ &tmp_next_block_ctx,
+ mirror_num);
+ if (ret) {
+ pr_info("btrfsic: btrfsic_map_block(root @%llu, mirror %d) failed!\n",
+ 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)PAGE_SIZE) {
+ pr_info("btrfsic: read @logical %llu failed!\n",
+ tmp_next_block_ctx.start);
+ btrfsic_release_block_ctx(&tmp_next_block_ctx);
+ kfree(selected_super);
+ return -1;
+ }
+
+ ret = btrfsic_process_metablock(state,
+ next_block,
+ &tmp_next_block_ctx,
+ 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_fs_info *fs_info = state->fs_info;
+ struct btrfs_super_block *super_tmp;
+ u64 dev_bytenr;
+ struct btrfsic_block *superblock_tmp;
+ int pass;
+ struct block_device *const superblock_bdev = device->bdev;
+ struct page *page;
+ struct address_space *mapping = superblock_bdev->bd_inode->i_mapping;
+ int ret = 0;
+
+ /* super block bytenr is always the unmapped device bytenr */
+ dev_bytenr = btrfs_sb_offset(superblock_mirror_num);
+ if (dev_bytenr + BTRFS_SUPER_INFO_SIZE > device->commit_total_bytes)
+ return -1;
+
+ page = read_cache_page_gfp(mapping, dev_bytenr >> PAGE_SHIFT, GFP_NOFS);
+ if (IS_ERR(page))
+ return -1;
+
+ super_tmp = page_address(page);
+
+ if (btrfs_super_bytenr(super_tmp) != dev_bytenr ||
+ btrfs_super_magic(super_tmp) != BTRFS_MAGIC ||
+ memcmp(device->uuid, super_tmp->dev_item.uuid, BTRFS_UUID_SIZE) ||
+ btrfs_super_nodesize(super_tmp) != state->metablock_size ||
+ btrfs_super_sectorsize(super_tmp) != state->datablock_size) {
+ ret = 0;
+ goto out;
+ }
+
+ 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) {
+ ret = -1;
+ goto out;
+ }
+ /* 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)
+ btrfs_info_in_rcu(fs_info,
+ "new initial S-block (bdev %p, %s) @%llu (%pg/%llu/%d)",
+ superblock_bdev,
+ btrfs_dev_name(device), dev_bytenr,
+ dev_state->bdev, 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:
+ btrfs_set_disk_key_objectid(&tmp_disk_key,
+ BTRFS_ROOT_TREE_OBJECTID);
+ additional_string = "initial root ";
+ next_bytenr = btrfs_super_root(super_tmp);
+ break;
+ case 1:
+ btrfs_set_disk_key_objectid(&tmp_disk_key,
+ BTRFS_CHUNK_TREE_OBJECTID);
+ additional_string = "initial chunk ";
+ next_bytenr = btrfs_super_chunk_root(super_tmp);
+ break;
+ case 2:
+ btrfs_set_disk_key_objectid(&tmp_disk_key,
+ 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(fs_info, next_bytenr,
+ state->metablock_size);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
+ pr_info("num_copies(log_bytenr=%llu) = %d\n",
+ 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,
+ state->metablock_size,
+ &tmp_next_block_ctx,
+ mirror_num)) {
+ pr_info("btrfsic: btrfsic_map_block(bytenr @%llu, mirror %d) failed!\n",
+ next_bytenr, mirror_num);
+ ret = -1;
+ goto out;
+ }
+
+ 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);
+ ret = -1;
+ goto out;
+ }
+
+ 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) {
+ ret = -1;
+ goto out;
+ }
+ }
+ }
+ if (state->print_mask & BTRFSIC_PRINT_MASK_INITIAL_ALL_TREES)
+ btrfsic_dump_tree_sub(state, superblock_tmp, 0);
+
+out:
+ put_page(page);
+ return ret;
+}
+
+static struct btrfsic_stack_frame *btrfsic_stack_frame_alloc(void)
+{
+ struct btrfsic_stack_frame *sf;
+
+ sf = kzalloc(sizeof(*sf), GFP_NOFS);
+ if (sf)
+ 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 noinline_for_stack int btrfsic_process_metablock(
+ struct btrfsic_state *state,
+ struct btrfsic_block *const first_block,
+ struct btrfsic_block_data_ctx *const first_block_ctx,
+ 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;
+ struct btrfs_header *const first_hdr =
+ (struct btrfs_header *)first_block_ctx->datav[0];
+
+ BUG_ON(!first_hdr);
+ 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 = btrfs_stack_header_generation(sf->hdr);
+ if (0 == sf->hdr->level) {
+ struct btrfs_leaf *const leafhdr =
+ (struct btrfs_leaf *)sf->hdr;
+
+ if (-1 == sf->i) {
+ sf->nr = btrfs_stack_header_nritems(&leafhdr->header);
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ pr_info("leaf %llu items %d generation %llu owner %llu\n",
+ sf->block_ctx->start, sf->nr,
+ btrfs_stack_header_generation(
+ &leafhdr->header),
+ btrfs_stack_header_owner(
+ &leafhdr->header));
+ }
+
+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;
+ u32 disk_item_offset =
+ (uintptr_t)(leafhdr->items + sf->i) -
+ (uintptr_t)leafhdr;
+ struct btrfs_disk_key *disk_key;
+ u8 type;
+ u32 item_offset;
+ u32 item_size;
+
+ if (disk_item_offset + sizeof(struct btrfs_item) >
+ sf->block_ctx->len) {
+leaf_item_out_of_bounce_error:
+ pr_info(
+ "btrfsic: leaf item out of bounce at logical %llu, dev %pg\n",
+ sf->block_ctx->start,
+ sf->block_ctx->dev->bdev);
+ goto one_stack_frame_backwards;
+ }
+ btrfsic_read_from_block_data(sf->block_ctx,
+ &disk_item,
+ disk_item_offset,
+ sizeof(struct btrfs_item));
+ item_offset = btrfs_stack_item_offset(&disk_item);
+ item_size = btrfs_stack_item_size(&disk_item);
+ disk_key = &disk_item.key;
+ type = btrfs_disk_key_type(disk_key);
+
+ if (BTRFS_ROOT_ITEM_KEY == type) {
+ struct btrfs_root_item root_item;
+ u32 root_item_offset;
+ u64 next_bytenr;
+
+ root_item_offset = item_offset +
+ offsetof(struct btrfs_leaf, items);
+ if (root_item_offset + item_size >
+ sf->block_ctx->len)
+ goto leaf_item_out_of_bounce_error;
+ btrfsic_read_from_block_data(
+ sf->block_ctx, &root_item,
+ root_item_offset,
+ item_size);
+ next_bytenr = btrfs_root_bytenr(&root_item);
+
+ 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,
+ btrfs_root_generation(
+ &root_item));
+ 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.datav[0];
+
+ next_stack =
+ btrfsic_stack_frame_alloc();
+ if (NULL == next_stack) {
+ sf->error = -1;
+ 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 = btrfs_stack_header_nritems(&nodehdr->header);
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ pr_info("node %llu level %d items %d generation %llu owner %llu\n",
+ sf->block_ctx->start,
+ nodehdr->header.level, sf->nr,
+ btrfs_stack_header_generation(
+ &nodehdr->header),
+ btrfs_stack_header_owner(
+ &nodehdr->header));
+ }
+
+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 key_ptr;
+ u32 key_ptr_offset;
+ u64 next_bytenr;
+
+ key_ptr_offset = (uintptr_t)(nodehdr->ptrs + sf->i) -
+ (uintptr_t)nodehdr;
+ if (key_ptr_offset + sizeof(struct btrfs_key_ptr) >
+ sf->block_ctx->len) {
+ pr_info(
+ "btrfsic: node item out of bounce at logical %llu, dev %pg\n",
+ sf->block_ctx->start,
+ sf->block_ctx->dev->bdev);
+ goto one_stack_frame_backwards;
+ }
+ btrfsic_read_from_block_data(
+ sf->block_ctx, &key_ptr, key_ptr_offset,
+ sizeof(struct btrfs_key_ptr));
+ next_bytenr = btrfs_stack_key_blockptr(&key_ptr);
+
+ 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,
+ &key_ptr.key,
+ btrfs_stack_key_generation(&key_ptr));
+ 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.datav[0];
+
+ next_stack = btrfsic_stack_frame_alloc();
+ if (NULL == next_stack) {
+ sf->error = -1;
+ 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 void btrfsic_read_from_block_data(
+ struct btrfsic_block_data_ctx *block_ctx,
+ void *dstv, u32 offset, size_t len)
+{
+ size_t cur;
+ size_t pgoff;
+ char *kaddr;
+ char *dst = (char *)dstv;
+ size_t start_offset = offset_in_page(block_ctx->start);
+ unsigned long i = (start_offset + offset) >> PAGE_SHIFT;
+
+ WARN_ON(offset + len > block_ctx->len);
+ pgoff = offset_in_page(start_offset + offset);
+
+ while (len > 0) {
+ cur = min(len, ((size_t)PAGE_SIZE - pgoff));
+ BUG_ON(i >= DIV_ROUND_UP(block_ctx->len, PAGE_SIZE));
+ kaddr = block_ctx->datav[i];
+ memcpy(dst, kaddr + pgoff, cur);
+
+ dst += cur;
+ len -= cur;
+ pgoff = 0;
+ i++;
+ }
+}
+
+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 btrfs_fs_info *fs_info = state->fs_info;
+ 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(fs_info, next_bytenr,
+ state->metablock_size);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
+ pr_info("num_copies(log_bytenr=%llu) = %d\n",
+ next_bytenr, *num_copiesp);
+ *mirror_nump = 1;
+ }
+
+ if (*mirror_nump > *num_copiesp)
+ return 0;
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ pr_info("btrfsic_create_link_to_next_block(mirror_num=%d)\n",
+ *mirror_nump);
+ ret = btrfsic_map_block(state, next_bytenr,
+ state->metablock_size,
+ next_block_ctx, *mirror_nump);
+ if (ret) {
+ pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n",
+ 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 (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) {
+ if (next_block->logical_bytenr != next_bytenr &&
+ !(!next_block->is_metadata &&
+ 0 == next_block->logical_bytenr))
+ pr_info(
+"referenced block @%llu (%pg/%llu/%d) found in hash table, %c, bytenr mismatch (!= stored %llu)\n",
+ next_bytenr, next_block_ctx->dev->bdev,
+ next_block_ctx->dev_bytenr, *mirror_nump,
+ btrfsic_get_block_type(state,
+ next_block),
+ next_block->logical_bytenr);
+ else
+ pr_info(
+ "referenced block @%llu (%pg/%llu/%d) found in hash table, %c\n",
+ next_bytenr, next_block_ctx->dev->bdev,
+ 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) {
+ 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)next_block_ctx->len) {
+ pr_info("btrfsic: read block @logical %llu failed!\n",
+ 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)
+{
+ struct btrfs_fs_info *fs_info = state->fs_info;
+ struct btrfs_file_extent_item file_extent_item;
+ u64 file_extent_item_offset;
+ u64 next_bytenr;
+ u64 num_bytes;
+ u64 generation;
+ struct btrfsic_block_link *l;
+ int ret;
+
+ file_extent_item_offset = offsetof(struct btrfs_leaf, items) +
+ item_offset;
+ if (file_extent_item_offset +
+ offsetof(struct btrfs_file_extent_item, disk_num_bytes) >
+ block_ctx->len) {
+ pr_info("btrfsic: file item out of bounce at logical %llu, dev %pg\n",
+ block_ctx->start, block_ctx->dev->bdev);
+ return -1;
+ }
+
+ btrfsic_read_from_block_data(block_ctx, &file_extent_item,
+ file_extent_item_offset,
+ offsetof(struct btrfs_file_extent_item, disk_num_bytes));
+ if (BTRFS_FILE_EXTENT_REG != file_extent_item.type ||
+ btrfs_stack_file_extent_disk_bytenr(&file_extent_item) == 0) {
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE)
+ pr_info("extent_data: type %u, disk_bytenr = %llu\n",
+ file_extent_item.type,
+ btrfs_stack_file_extent_disk_bytenr(
+ &file_extent_item));
+ return 0;
+ }
+
+ if (file_extent_item_offset + sizeof(struct btrfs_file_extent_item) >
+ block_ctx->len) {
+ pr_info("btrfsic: file item out of bounce at logical %llu, dev %pg\n",
+ block_ctx->start, block_ctx->dev->bdev);
+ return -1;
+ }
+ btrfsic_read_from_block_data(block_ctx, &file_extent_item,
+ file_extent_item_offset,
+ sizeof(struct btrfs_file_extent_item));
+ next_bytenr = btrfs_stack_file_extent_disk_bytenr(&file_extent_item);
+ if (btrfs_stack_file_extent_compression(&file_extent_item) ==
+ BTRFS_COMPRESS_NONE) {
+ next_bytenr += btrfs_stack_file_extent_offset(&file_extent_item);
+ num_bytes = btrfs_stack_file_extent_num_bytes(&file_extent_item);
+ } else {
+ num_bytes = btrfs_stack_file_extent_disk_num_bytes(&file_extent_item);
+ }
+ generation = btrfs_stack_file_extent_generation(&file_extent_item);
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE)
+ pr_info("extent_data: type %u, disk_bytenr = %llu, offset = %llu, num_bytes = %llu\n",
+ file_extent_item.type,
+ btrfs_stack_file_extent_disk_bytenr(&file_extent_item),
+ btrfs_stack_file_extent_offset(&file_extent_item),
+ num_bytes);
+ while (num_bytes > 0) {
+ u32 chunk_len;
+ int num_copies;
+ int mirror_num;
+
+ if (num_bytes > state->datablock_size)
+ chunk_len = state->datablock_size;
+ else
+ chunk_len = num_bytes;
+
+ num_copies = btrfs_num_copies(fs_info, next_bytenr,
+ state->datablock_size);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
+ pr_info("num_copies(log_bytenr=%llu) = %d\n",
+ 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)
+ pr_info("btrfsic_handle_extent_data(mirror_num=%d)\n",
+ mirror_num);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERY_VERBOSE)
+ pr_info("\tdisk_bytenr = %llu, num_bytes %u\n",
+ next_bytenr, chunk_len);
+ ret = btrfsic_map_block(state, next_bytenr,
+ chunk_len, &next_block_ctx,
+ mirror_num);
+ if (ret) {
+ pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n",
+ 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) {
+ btrfsic_release_block_ctx(&next_block_ctx);
+ return -1;
+ }
+ if (!block_was_created) {
+ if ((state->print_mask &
+ BTRFSIC_PRINT_MASK_VERBOSE) &&
+ next_block->logical_bytenr != next_bytenr &&
+ !(!next_block->is_metadata &&
+ 0 == next_block->logical_bytenr)) {
+ pr_info(
+"referenced block @%llu (%pg/%llu/%d) found in hash table, D, bytenr mismatch (!= stored %llu)\n",
+ next_bytenr,
+ next_block_ctx.dev->bdev,
+ next_block_ctx.dev_bytenr,
+ mirror_num,
+ 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)
+{
+ struct btrfs_fs_info *fs_info = state->fs_info;
+ int ret;
+ u64 length;
+ struct btrfs_io_context *bioc = NULL;
+ struct btrfs_io_stripe smap, *map;
+ struct btrfs_device *device;
+
+ length = len;
+ ret = btrfs_map_block(fs_info, BTRFS_MAP_READ, bytenr, &length, &bioc,
+ NULL, &mirror_num, 0);
+ if (ret) {
+ block_ctx_out->start = 0;
+ block_ctx_out->dev_bytenr = 0;
+ block_ctx_out->len = 0;
+ block_ctx_out->dev = NULL;
+ block_ctx_out->datav = NULL;
+ block_ctx_out->pagev = NULL;
+ block_ctx_out->mem_to_free = NULL;
+
+ return ret;
+ }
+
+ if (bioc)
+ map = &bioc->stripes[0];
+ else
+ map = &smap;
+
+ device = map->dev;
+ if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state) ||
+ !device->bdev || !device->name)
+ block_ctx_out->dev = NULL;
+ else
+ block_ctx_out->dev = btrfsic_dev_state_lookup(
+ device->bdev->bd_dev);
+ block_ctx_out->dev_bytenr = map->physical;
+ block_ctx_out->start = bytenr;
+ block_ctx_out->len = len;
+ block_ctx_out->datav = NULL;
+ block_ctx_out->pagev = NULL;
+ block_ctx_out->mem_to_free = NULL;
+
+ kfree(bioc);
+ if (NULL == block_ctx_out->dev) {
+ ret = -ENXIO;
+ pr_info("btrfsic: error, cannot lookup dev (#1)!\n");
+ }
+
+ return ret;
+}
+
+static void btrfsic_release_block_ctx(struct btrfsic_block_data_ctx *block_ctx)
+{
+ if (block_ctx->mem_to_free) {
+ unsigned int num_pages;
+
+ BUG_ON(!block_ctx->datav);
+ BUG_ON(!block_ctx->pagev);
+ num_pages = (block_ctx->len + (u64)PAGE_SIZE - 1) >>
+ PAGE_SHIFT;
+ /* Pages must be unmapped in reverse order */
+ while (num_pages > 0) {
+ num_pages--;
+ if (block_ctx->datav[num_pages])
+ block_ctx->datav[num_pages] = NULL;
+ if (block_ctx->pagev[num_pages]) {
+ __free_page(block_ctx->pagev[num_pages]);
+ block_ctx->pagev[num_pages] = NULL;
+ }
+ }
+
+ kfree(block_ctx->mem_to_free);
+ block_ctx->mem_to_free = NULL;
+ block_ctx->pagev = NULL;
+ block_ctx->datav = NULL;
+ }
+}
+
+static int btrfsic_read_block(struct btrfsic_state *state,
+ struct btrfsic_block_data_ctx *block_ctx)
+{
+ unsigned int num_pages;
+ unsigned int i;
+ size_t size;
+ u64 dev_bytenr;
+ int ret;
+
+ BUG_ON(block_ctx->datav);
+ BUG_ON(block_ctx->pagev);
+ BUG_ON(block_ctx->mem_to_free);
+ if (!PAGE_ALIGNED(block_ctx->dev_bytenr)) {
+ pr_info("btrfsic: read_block() with unaligned bytenr %llu\n",
+ block_ctx->dev_bytenr);
+ return -1;
+ }
+
+ num_pages = (block_ctx->len + (u64)PAGE_SIZE - 1) >>
+ PAGE_SHIFT;
+ size = sizeof(*block_ctx->datav) + sizeof(*block_ctx->pagev);
+ block_ctx->mem_to_free = kcalloc(num_pages, size, GFP_NOFS);
+ if (!block_ctx->mem_to_free)
+ return -ENOMEM;
+ block_ctx->datav = block_ctx->mem_to_free;
+ block_ctx->pagev = (struct page **)(block_ctx->datav + num_pages);
+ ret = btrfs_alloc_page_array(num_pages, block_ctx->pagev);
+ if (ret)
+ return ret;
+
+ dev_bytenr = block_ctx->dev_bytenr;
+ for (i = 0; i < num_pages;) {
+ struct bio *bio;
+ unsigned int j;
+
+ bio = bio_alloc(block_ctx->dev->bdev, num_pages - i,
+ REQ_OP_READ, GFP_NOFS);
+ bio->bi_iter.bi_sector = dev_bytenr >> SECTOR_SHIFT;
+
+ for (j = i; j < num_pages; j++) {
+ ret = bio_add_page(bio, block_ctx->pagev[j],
+ PAGE_SIZE, 0);
+ if (PAGE_SIZE != ret)
+ break;
+ }
+ if (j == i) {
+ pr_info("btrfsic: error, failed to add a single page!\n");
+ return -1;
+ }
+ if (submit_bio_wait(bio)) {
+ pr_info("btrfsic: read error at logical %llu dev %pg!\n",
+ block_ctx->start, block_ctx->dev->bdev);
+ bio_put(bio);
+ return -1;
+ }
+ bio_put(bio);
+ dev_bytenr += (j - i) * PAGE_SIZE;
+ i = j;
+ }
+ for (i = 0; i < num_pages; i++)
+ block_ctx->datav[i] = page_address(block_ctx->pagev[i]);
+
+ return block_ctx->len;
+}
+
+static void btrfsic_dump_database(struct btrfsic_state *state)
+{
+ const struct btrfsic_block *b_all;
+
+ BUG_ON(NULL == state);
+
+ pr_info("all_blocks_list:\n");
+ list_for_each_entry(b_all, &state->all_blocks_list, all_blocks_node) {
+ const struct btrfsic_block_link *l;
+
+ pr_info("%c-block @%llu (%pg/%llu/%d)\n",
+ btrfsic_get_block_type(state, b_all),
+ b_all->logical_bytenr, b_all->dev_state->bdev,
+ b_all->dev_bytenr, b_all->mirror_num);
+
+ list_for_each_entry(l, &b_all->ref_to_list, node_ref_to) {
+ pr_info(
+ " %c @%llu (%pg/%llu/%d) refers %u* to %c @%llu (%pg/%llu/%d)\n",
+ btrfsic_get_block_type(state, b_all),
+ b_all->logical_bytenr, b_all->dev_state->bdev,
+ b_all->dev_bytenr, b_all->mirror_num,
+ l->ref_cnt,
+ btrfsic_get_block_type(state, l->block_ref_to),
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->bdev,
+ l->block_ref_to->dev_bytenr,
+ l->block_ref_to->mirror_num);
+ }
+
+ list_for_each_entry(l, &b_all->ref_from_list, node_ref_from) {
+ pr_info(
+ " %c @%llu (%pg/%llu/%d) is ref %u* from %c @%llu (%pg/%llu/%d)\n",
+ btrfsic_get_block_type(state, b_all),
+ b_all->logical_bytenr, b_all->dev_state->bdev,
+ b_all->dev_bytenr, b_all->mirror_num,
+ l->ref_cnt,
+ btrfsic_get_block_type(state, l->block_ref_from),
+ l->block_ref_from->logical_bytenr,
+ l->block_ref_from->dev_state->bdev,
+ l->block_ref_from->dev_bytenr,
+ l->block_ref_from->mirror_num);
+ }
+
+ pr_info("\n");
+ }
+}
+
+/*
+ * Test whether the disk block contains a tree block (leaf or node)
+ * (note that this test fails for the super block)
+ */
+static noinline_for_stack int btrfsic_test_for_metadata(
+ struct btrfsic_state *state,
+ char **datav, unsigned int num_pages)
+{
+ struct btrfs_fs_info *fs_info = state->fs_info;
+ SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
+ struct btrfs_header *h;
+ u8 csum[BTRFS_CSUM_SIZE];
+ unsigned int i;
+
+ if (num_pages * PAGE_SIZE < state->metablock_size)
+ return 1; /* not metadata */
+ num_pages = state->metablock_size >> PAGE_SHIFT;
+ h = (struct btrfs_header *)datav[0];
+
+ if (memcmp(h->fsid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE))
+ return 1;
+
+ shash->tfm = fs_info->csum_shash;
+ crypto_shash_init(shash);
+
+ for (i = 0; i < num_pages; i++) {
+ u8 *data = i ? datav[i] : (datav[i] + BTRFS_CSUM_SIZE);
+ size_t sublen = i ? PAGE_SIZE :
+ (PAGE_SIZE - BTRFS_CSUM_SIZE);
+
+ crypto_shash_update(shash, data, sublen);
+ }
+ crypto_shash_final(shash, csum);
+ if (memcmp(csum, h->csum, fs_info->csum_size))
+ return 1;
+
+ return 0; /* is metadata */
+}
+
+static void btrfsic_process_written_block(struct btrfsic_dev_state *dev_state,
+ u64 dev_bytenr, char **mapped_datav,
+ unsigned int num_pages,
+ struct bio *bio, int *bio_is_patched,
+ blk_opf_t 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;
+ unsigned int processed_len;
+
+ if (NULL != bio_is_patched)
+ *bio_is_patched = 0;
+
+again:
+ if (num_pages == 0)
+ return;
+
+ processed_len = 0;
+ is_metadata = (0 == btrfsic_test_for_metadata(state, mapped_datav,
+ num_pages));
+
+ block = btrfsic_block_hashtable_lookup(bdev, dev_bytenr,
+ &state->block_hashtable);
+ if (NULL != block) {
+ u64 bytenr = 0;
+ struct btrfsic_block_link *l, *tmp;
+
+ if (block->is_superblock) {
+ bytenr = btrfs_super_bytenr((struct btrfs_super_block *)
+ mapped_datav[0]);
+ if (num_pages * PAGE_SIZE <
+ BTRFS_SUPER_INFO_SIZE) {
+ pr_info("btrfsic: cannot work with too short bios!\n");
+ return;
+ }
+ is_metadata = 1;
+ BUG_ON(!PAGE_ALIGNED(BTRFS_SUPER_INFO_SIZE));
+ processed_len = BTRFS_SUPER_INFO_SIZE;
+ if (state->print_mask &
+ BTRFSIC_PRINT_MASK_TREE_BEFORE_SB_WRITE) {
+ pr_info("[before new superblock is written]:\n");
+ btrfsic_dump_tree_sub(state, block, 0);
+ }
+ }
+ if (is_metadata) {
+ if (!block->is_superblock) {
+ if (num_pages * PAGE_SIZE <
+ state->metablock_size) {
+ pr_info("btrfsic: cannot work with too short bios!\n");
+ return;
+ }
+ processed_len = state->metablock_size;
+ bytenr = btrfs_stack_header_bytenr(
+ (struct btrfs_header *)
+ mapped_datav[0]);
+ btrfsic_cmp_log_and_dev_bytenr(state, bytenr,
+ dev_state,
+ dev_bytenr);
+ }
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE) {
+ if (block->logical_bytenr != bytenr &&
+ !(!block->is_metadata &&
+ block->logical_bytenr == 0))
+ pr_info(
+"written block @%llu (%pg/%llu/%d) found in hash table, %c, bytenr mismatch (!= stored %llu)\n",
+ bytenr, dev_state->bdev,
+ dev_bytenr,
+ block->mirror_num,
+ btrfsic_get_block_type(state,
+ block),
+ block->logical_bytenr);
+ else
+ pr_info(
+ "written block @%llu (%pg/%llu/%d) found in hash table, %c\n",
+ bytenr, dev_state->bdev,
+ dev_bytenr, block->mirror_num,
+ btrfsic_get_block_type(state,
+ block));
+ }
+ block->logical_bytenr = bytenr;
+ } else {
+ if (num_pages * PAGE_SIZE <
+ state->datablock_size) {
+ pr_info("btrfsic: cannot work with too short bios!\n");
+ return;
+ }
+ processed_len = state->datablock_size;
+ bytenr = block->logical_bytenr;
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ pr_info(
+ "written block @%llu (%pg/%llu/%d) found in hash table, %c\n",
+ bytenr, dev_state->bdev, dev_bytenr,
+ block->mirror_num,
+ btrfsic_get_block_type(state, block));
+ }
+
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ pr_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)) {
+ pr_info(
+"btrfs: attempt to overwrite %c-block @%llu (%pg/%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), bytenr,
+ dev_state->bdev, dev_bytenr, block->mirror_num,
+ block->generation,
+ btrfs_disk_key_objectid(&block->disk_key),
+ block->disk_key.type,
+ btrfs_disk_key_offset(&block->disk_key),
+ btrfs_stack_header_generation(
+ (struct btrfs_header *) mapped_datav[0]),
+ state->max_superblock_generation);
+ btrfsic_dump_tree(state);
+ }
+
+ if (!block->is_iodone && !block->never_written) {
+ pr_info(
+"btrfs: attempt to overwrite %c-block @%llu (%pg/%llu/%d), oldgen=%llu, newgen=%llu, which is not yet iodone!\n",
+ btrfsic_get_block_type(state, block), bytenr,
+ dev_state->bdev, dev_bytenr, block->mirror_num,
+ block->generation,
+ btrfs_stack_header_generation(
+ (struct btrfs_header *)
+ mapped_datav[0]));
+ /* it would not be safe to go on */
+ btrfsic_dump_tree(state);
+ goto continue_loop;
+ }
+
+ /*
+ * Clear all references of this block. Do not free
+ * the block itself even if is not referenced anymore
+ * because it still carries valuable information
+ * like whether it was ever written and IO completed.
+ */
+ list_for_each_entry_safe(l, tmp, &block->ref_to_list,
+ 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);
+ }
+ }
+
+ block_ctx.dev = dev_state;
+ block_ctx.dev_bytenr = dev_bytenr;
+ block_ctx.start = bytenr;
+ block_ctx.len = processed_len;
+ block_ctx.pagev = NULL;
+ block_ctx.mem_to_free = NULL;
+ block_ctx.datav = mapped_datav;
+
+ 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_private =
+ bio->bi_private;
+ block->orig_bio_end_io =
+ 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_private =
+ chained_block->orig_bio_private;
+ block->orig_bio_end_io =
+ chained_block->orig_bio_end_io;
+ block->next_in_same_bio = chained_block;
+ bio->bi_private = block;
+ }
+ } else {
+ block->is_iodone = 1;
+ block->orig_bio_private = NULL;
+ block->orig_bio_end_io = 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) {
+ BUG_ON(PAGE_SIZE !=
+ BTRFS_SUPER_INFO_SIZE);
+ ret = btrfsic_process_written_superblock(
+ state,
+ block,
+ (struct btrfs_super_block *)
+ mapped_datav[0]);
+ if (state->print_mask &
+ BTRFSIC_PRINT_MASK_TREE_AFTER_SB_WRITE) {
+ pr_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,
+ 0, 0);
+ }
+ if (ret)
+ pr_info("btrfsic: btrfsic_process_metablock(root @%llu) failed!\n",
+ 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) {
+ processed_len = state->datablock_size;
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ pr_info(
+ "written block (%pg/%llu/?) !found in hash table, D\n",
+ dev_state->bdev, dev_bytenr);
+ if (!state->include_extent_data) {
+ /* ignore that written D block */
+ goto continue_loop;
+ }
+
+ /* this is getting ugly for the
+ * include_extent_data case... */
+ bytenr = 0; /* unknown */
+ } else {
+ processed_len = state->metablock_size;
+ bytenr = btrfs_stack_header_bytenr(
+ (struct btrfs_header *)
+ mapped_datav[0]);
+ btrfsic_cmp_log_and_dev_bytenr(state, bytenr, dev_state,
+ dev_bytenr);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ pr_info(
+ "written block @%llu (%pg/%llu/?) !found in hash table, M\n",
+ bytenr, dev_state->bdev, dev_bytenr);
+ }
+
+ block_ctx.dev = dev_state;
+ block_ctx.dev_bytenr = dev_bytenr;
+ block_ctx.start = bytenr;
+ block_ctx.len = processed_len;
+ block_ctx.pagev = NULL;
+ block_ctx.mem_to_free = NULL;
+ block_ctx.datav = mapped_datav;
+
+ block = btrfsic_block_alloc();
+ if (NULL == block) {
+ btrfsic_release_block_ctx(&block_ctx);
+ goto continue_loop;
+ }
+ 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_private = bio->bi_private;
+ block->orig_bio_end_io = 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_private =
+ chained_block->orig_bio_private;
+ block->orig_bio_end_io =
+ chained_block->orig_bio_end_io;
+ block->next_in_same_bio = chained_block;
+ bio->bi_private = block;
+ }
+ } else {
+ block->is_iodone = 1;
+ block->orig_bio_private = NULL;
+ block->orig_bio_end_io = NULL;
+ block->next_in_same_bio = NULL;
+ }
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ pr_info("new written %c-block @%llu (%pg/%llu/%d)\n",
+ is_metadata ? 'M' : 'D',
+ block->logical_bytenr, block->dev_state->bdev,
+ 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, 0, 0);
+ if (ret)
+ pr_info("btrfsic: process_metablock(root @%llu) failed!\n",
+ dev_bytenr);
+ }
+ btrfsic_release_block_ctx(&block_ctx);
+ }
+
+continue_loop:
+ BUG_ON(!processed_len);
+ dev_bytenr += processed_len;
+ mapped_datav += processed_len >> PAGE_SHIFT;
+ num_pages -= processed_len >> PAGE_SHIFT;
+ goto again;
+}
+
+static void btrfsic_bio_end_io(struct bio *bp)
+{
+ struct btrfsic_block *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 (bp->bi_status)
+ iodone_w_error = 1;
+
+ BUG_ON(NULL == block);
+ bp->bi_private = block->orig_bio_private;
+ bp->bi_end_io = block->orig_bio_end_io;
+
+ 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))
+ pr_info("bio_end_io(err=%d) for %c @%llu (%pg/%llu/%d)\n",
+ bp->bi_status,
+ btrfsic_get_block_type(dev_state->state, block),
+ block->logical_bytenr, dev_state->bdev,
+ 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_PREFLUSH) {
+ dev_state->last_flush_gen++;
+ if ((dev_state->state->print_mask &
+ BTRFSIC_PRINT_MASK_END_IO_BIO_BH))
+ pr_info("bio_end_io() new %pg flush_gen=%llu\n",
+ dev_state->bdev,
+ 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);
+}
+
+static int btrfsic_process_written_superblock(
+ struct btrfsic_state *state,
+ struct btrfsic_block *const superblock,
+ struct btrfs_super_block *const super_hdr)
+{
+ struct btrfs_fs_info *fs_info = state->fs_info;
+ 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)
+ pr_info(
+ "btrfsic: superblock @%llu (%pg/%llu/%d) with old gen %llu <= %llu\n",
+ superblock->logical_bytenr,
+ superblock->dev_state->bdev,
+ superblock->dev_bytenr, superblock->mirror_num,
+ btrfs_super_generation(super_hdr),
+ state->max_superblock_generation);
+ } else {
+ if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
+ pr_info(
+ "btrfsic: got new superblock @%llu (%pg/%llu/%d) with new gen %llu > %llu\n",
+ superblock->logical_bytenr,
+ superblock->dev_state->bdev,
+ superblock->dev_bytenr, superblock->mirror_num,
+ btrfs_super_generation(super_hdr),
+ 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 = {0};
+
+ btrfs_set_disk_key_objectid(&tmp_disk_key,
+ BTRFS_ROOT_ITEM_KEY);
+ btrfs_set_disk_key_objectid(&tmp_disk_key, 0);
+
+ switch (pass) {
+ case 0:
+ btrfs_set_disk_key_objectid(&tmp_disk_key,
+ 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)
+ pr_info("root@%llu\n", next_bytenr);
+ break;
+ case 1:
+ btrfs_set_disk_key_objectid(&tmp_disk_key,
+ 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)
+ pr_info("chunk@%llu\n", next_bytenr);
+ break;
+ case 2:
+ btrfs_set_disk_key_objectid(&tmp_disk_key,
+ 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)
+ pr_info("log@%llu\n", next_bytenr);
+ break;
+ }
+
+ num_copies = btrfs_num_copies(fs_info, next_bytenr,
+ BTRFS_SUPER_INFO_SIZE);
+ if (state->print_mask & BTRFSIC_PRINT_MASK_NUM_COPIES)
+ pr_info("num_copies(log_bytenr=%llu) = %d\n",
+ 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)
+ pr_info("btrfsic_process_written_superblock(mirror_num=%d)\n", mirror_num);
+ ret = btrfsic_map_block(state, next_bytenr,
+ BTRFS_SUPER_INFO_SIZE,
+ &tmp_next_block_ctx,
+ mirror_num);
+ if (ret) {
+ pr_info("btrfsic: btrfsic_map_block(@%llu, mirror=%d) failed!\n",
+ 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) {
+ 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 (WARN_ON(-1 == btrfsic_check_all_ref_blocks(state, superblock, 0)))
+ 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)
+{
+ const struct btrfsic_block_link *l;
+ 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 information. This
+ * causes no harm unless such blocks are referenced
+ * by the most recent super block.
+ */
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ pr_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_entry(l, &block->ref_to_list, node_ref_to) {
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ pr_info(
+ "rl=%d, %c @%llu (%pg/%llu/%d) %u* refers to %c @%llu (%pg/%llu/%d)\n",
+ recursion_level,
+ btrfsic_get_block_type(state, block),
+ block->logical_bytenr, block->dev_state->bdev,
+ block->dev_bytenr, block->mirror_num,
+ l->ref_cnt,
+ btrfsic_get_block_type(state, l->block_ref_to),
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->bdev,
+ l->block_ref_to->dev_bytenr,
+ l->block_ref_to->mirror_num);
+ if (l->block_ref_to->never_written) {
+ pr_info(
+"btrfs: attempt to write superblock which references block %c @%llu (%pg/%llu/%d) which is never written!\n",
+ btrfsic_get_block_type(state, l->block_ref_to),
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->bdev,
+ l->block_ref_to->dev_bytenr,
+ l->block_ref_to->mirror_num);
+ ret = -1;
+ } else if (!l->block_ref_to->is_iodone) {
+ pr_info(
+"btrfs: attempt to write superblock which references block %c @%llu (%pg/%llu/%d) which is not yet iodone!\n",
+ btrfsic_get_block_type(state, l->block_ref_to),
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->bdev,
+ l->block_ref_to->dev_bytenr,
+ l->block_ref_to->mirror_num);
+ ret = -1;
+ } else if (l->block_ref_to->iodone_w_error) {
+ pr_info(
+"btrfs: attempt to write superblock which references block %c @%llu (%pg/%llu/%d) which has write error!\n",
+ btrfsic_get_block_type(state, l->block_ref_to),
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->bdev,
+ 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) {
+ pr_info(
+"btrfs: attempt to write superblock which references block %c @%llu (%pg/%llu/%d) with generation %llu != parent generation %llu!\n",
+ btrfsic_get_block_type(state, l->block_ref_to),
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->bdev,
+ l->block_ref_to->dev_bytenr,
+ l->block_ref_to->mirror_num,
+ l->block_ref_to->generation,
+ l->parent_generation);
+ ret = -1;
+ } else if (l->block_ref_to->flush_gen >
+ l->block_ref_to->dev_state->last_flush_gen) {
+ pr_info(
+"btrfs: attempt to write superblock which references block %c @%llu (%pg/%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),
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->bdev,
+ l->block_ref_to->dev_bytenr,
+ l->block_ref_to->mirror_num, block->flush_gen,
+ 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)
+{
+ const struct btrfsic_block_link *l;
+
+ if (recursion_level >= 3 + BTRFS_MAX_LEVEL) {
+ /* refer to comment at "abort cyclic linkage (case 1)" */
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ pr_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_entry(l, &block->ref_from_list, node_ref_from) {
+ if (state->print_mask & BTRFSIC_PRINT_MASK_VERBOSE)
+ pr_info(
+ "rl=%d, %c @%llu (%pg/%llu/%d) is ref %u* from %c @%llu (%pg/%llu/%d)\n",
+ recursion_level,
+ btrfsic_get_block_type(state, block),
+ block->logical_bytenr, block->dev_state->bdev,
+ block->dev_bytenr, block->mirror_num,
+ l->ref_cnt,
+ btrfsic_get_block_type(state, l->block_ref_from),
+ l->block_ref_from->logical_bytenr,
+ l->block_ref_from->dev_state->bdev,
+ 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)
+{
+ pr_info("add %u* link from %c @%llu (%pg/%llu/%d) to %c @%llu (%pg/%llu/%d)\n",
+ l->ref_cnt,
+ btrfsic_get_block_type(state, l->block_ref_from),
+ l->block_ref_from->logical_bytenr,
+ l->block_ref_from->dev_state->bdev,
+ l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num,
+ btrfsic_get_block_type(state, l->block_ref_to),
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->bdev, 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)
+{
+ pr_info("rem %u* link from %c @%llu (%pg/%llu/%d) to %c @%llu (%pg/%llu/%d)\n",
+ l->ref_cnt,
+ btrfsic_get_block_type(state, l->block_ref_from),
+ l->block_ref_from->logical_bytenr,
+ l->block_ref_from->dev_state->bdev,
+ l->block_ref_from->dev_bytenr, l->block_ref_from->mirror_num,
+ btrfsic_get_block_type(state, l->block_ref_to),
+ l->block_ref_to->logical_bytenr,
+ l->block_ref_to->dev_state->bdev, 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)
+{
+ const struct btrfsic_block_link *l;
+ 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(%pg/%llu/%u)",
+ btrfsic_get_block_type(state, block),
+ block->logical_bytenr, block->dev_state->bdev,
+ 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_entry(l, &block->ref_to_list, 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 (!l)
+ 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 (!block)
+ return NULL;
+
+ dev_state = btrfsic_dev_state_lookup(block_ctx->dev->bdev->bd_dev);
+ if (NULL == dev_state) {
+ pr_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)
+ pr_info("New %s%c-block @%llu (%pg/%llu/%d)\n",
+ additional_string,
+ btrfsic_get_block_type(state, block),
+ block->logical_bytenr, dev_state->bdev,
+ 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)
+{
+ struct btrfs_fs_info *fs_info = state->fs_info;
+ struct btrfsic_block_data_ctx block_ctx;
+ int num_copies;
+ int mirror_num;
+ int match = 0;
+ int ret;
+
+ num_copies = btrfs_num_copies(fs_info, bytenr, state->metablock_size);
+
+ for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
+ ret = btrfsic_map_block(state, bytenr, state->metablock_size,
+ &block_ctx, mirror_num);
+ if (ret) {
+ pr_info("btrfsic: btrfsic_map_block(logical @%llu, mirror %d) failed!\n",
+ 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 (WARN_ON(!match)) {
+ pr_info(
+"btrfs: attempt to write M-block which contains logical bytenr that doesn't map to dev+physical bytenr of submit_bio, buffer->log_bytenr=%llu, submit_bio(bdev=%pg, phys_bytenr=%llu)!\n",
+ bytenr, dev_state->bdev, dev_bytenr);
+ for (mirror_num = 1; mirror_num <= num_copies; mirror_num++) {
+ ret = btrfsic_map_block(state, bytenr,
+ state->metablock_size,
+ &block_ctx, mirror_num);
+ if (ret)
+ continue;
+
+ pr_info("read logical bytenr @%llu maps to (%pg/%llu/%d)\n",
+ bytenr, block_ctx.dev->bdev,
+ block_ctx.dev_bytenr, mirror_num);
+ }
+ }
+}
+
+static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev)
+{
+ return btrfsic_dev_state_hashtable_lookup(dev,
+ &btrfsic_dev_state_hashtable);
+}
+
+static void btrfsic_check_write_bio(struct bio *bio, struct btrfsic_dev_state *dev_state)
+{
+ unsigned int segs = bio_segments(bio);
+ u64 dev_bytenr = 512 * bio->bi_iter.bi_sector;
+ u64 cur_bytenr = dev_bytenr;
+ struct bvec_iter iter;
+ struct bio_vec bvec;
+ char **mapped_datav;
+ int bio_is_patched = 0;
+ int i = 0;
+
+ if (dev_state->state->print_mask & BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
+ pr_info(
+"submit_bio(rw=%d,0x%x, bi_vcnt=%u, bi_sector=%llu (bytenr %llu), bi_bdev=%p)\n",
+ bio_op(bio), bio->bi_opf, segs,
+ bio->bi_iter.bi_sector, dev_bytenr, bio->bi_bdev);
+
+ mapped_datav = kmalloc_array(segs, sizeof(*mapped_datav), GFP_NOFS);
+ if (!mapped_datav)
+ return;
+
+ bio_for_each_segment(bvec, bio, iter) {
+ BUG_ON(bvec.bv_len != PAGE_SIZE);
+ mapped_datav[i] = page_address(bvec.bv_page);
+ i++;
+
+ if (dev_state->state->print_mask &
+ BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE)
+ pr_info("#%u: bytenr=%llu, len=%u, offset=%u\n",
+ i, cur_bytenr, bvec.bv_len, bvec.bv_offset);
+ cur_bytenr += bvec.bv_len;
+ }
+
+ btrfsic_process_written_block(dev_state, dev_bytenr, mapped_datav, segs,
+ bio, &bio_is_patched, bio->bi_opf);
+ kfree(mapped_datav);
+}
+
+static void btrfsic_check_flush_bio(struct bio *bio, struct btrfsic_dev_state *dev_state)
+{
+ if (dev_state->state->print_mask & BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
+ pr_info("submit_bio(rw=%d,0x%x FLUSH, bdev=%p)\n",
+ bio_op(bio), bio->bi_opf, bio->bi_bdev);
+
+ if (dev_state->dummy_block_for_bio_bh_flush.is_iodone) {
+ 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 = bio->bi_opf;
+ block->orig_bio_private = bio->bi_private;
+ block->orig_bio_end_io = bio->bi_end_io;
+ block->next_in_same_bio = NULL;
+ bio->bi_private = block;
+ bio->bi_end_io = btrfsic_bio_end_io;
+ } else if ((dev_state->state->print_mask &
+ (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH |
+ BTRFSIC_PRINT_MASK_VERBOSE))) {
+ pr_info(
+"btrfsic_submit_bio(%pg) with FLUSH but dummy block already in use (ignored)!\n",
+ dev_state->bdev);
+ }
+}
+
+void btrfsic_check_bio(struct bio *bio)
+{
+ struct btrfsic_dev_state *dev_state;
+
+ if (!btrfsic_is_initialized)
+ return;
+
+ /*
+ * We can be called before btrfsic_mount, so there might not be a
+ * dev_state.
+ */
+ dev_state = btrfsic_dev_state_lookup(bio->bi_bdev->bd_dev);
+ mutex_lock(&btrfsic_mutex);
+ if (dev_state) {
+ if (bio_op(bio) == REQ_OP_WRITE && bio_has_data(bio))
+ btrfsic_check_write_bio(bio, dev_state);
+ else if (bio->bi_opf & REQ_PREFLUSH)
+ btrfsic_check_flush_bio(bio, dev_state);
+ }
+ mutex_unlock(&btrfsic_mutex);
+}
+
+int btrfsic_mount(struct btrfs_fs_info *fs_info,
+ 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;
+
+ if (!PAGE_ALIGNED(fs_info->nodesize)) {
+ pr_info("btrfsic: cannot handle nodesize %d not being a multiple of PAGE_SIZE %ld!\n",
+ fs_info->nodesize, PAGE_SIZE);
+ return -1;
+ }
+ if (!PAGE_ALIGNED(fs_info->sectorsize)) {
+ pr_info("btrfsic: cannot handle sectorsize %d not being a multiple of PAGE_SIZE %ld!\n",
+ fs_info->sectorsize, PAGE_SIZE);
+ return -1;
+ }
+ state = kvzalloc(sizeof(*state), GFP_KERNEL);
+ if (!state)
+ return -ENOMEM;
+
+ 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->fs_info = fs_info;
+ state->print_mask = print_mask;
+ state->include_extent_data = including_extent_data;
+ state->metablock_size = fs_info->nodesize;
+ state->datablock_size = fs_info->sectorsize;
+ 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;
+
+ if (!device->bdev || !device->name)
+ continue;
+
+ ds = btrfsic_dev_state_alloc();
+ if (NULL == ds) {
+ mutex_unlock(&btrfsic_mutex);
+ return -ENOMEM;
+ }
+ ds->bdev = device->bdev;
+ ds->state = state;
+ 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(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_fs_devices *fs_devices)
+{
+ struct btrfsic_block *b_all, *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->bd_dev,
+ &btrfsic_dev_state_hashtable);
+ if (NULL != ds) {
+ state = ds->state;
+ btrfsic_dev_state_hashtable_remove(ds);
+ btrfsic_dev_state_free(ds);
+ }
+ }
+
+ if (NULL == state) {
+ pr_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_entry_safe(b_all, tmp_all, &state->all_blocks_list,
+ all_blocks_node) {
+ struct btrfsic_block_link *l, *tmp;
+
+ list_for_each_entry_safe(l, tmp, &b_all->ref_to_list,
+ 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 || b_all->never_written)
+ btrfsic_block_free(b_all);
+ else
+ pr_info(
+"btrfs: attempt to free %c-block @%llu (%pg/%llu/%d) on umount which is not yet iodone!\n",
+ btrfsic_get_block_type(state, b_all),
+ b_all->logical_bytenr, b_all->dev_state->bdev,
+ b_all->dev_bytenr, b_all->mirror_num);
+ }
+
+ mutex_unlock(&btrfsic_mutex);
+
+ kvfree(state);
+}