This tree is not created by mkfs.btrfs. Therefore when a filesystem
is mounted writable and the UUID tree does not exist, this tree is
created if required. The tree is also added to the fs_info structure
and initialized, but this commit does not yet read or write UUID tree
elements.
Signed-off-by: Stefan Behrens <sbehr...@giantdisaster.de>
---
fs/btrfs/ctree.h | 1 +
fs/btrfs/disk-io.c | 40 +++++++++++++++++++++++++++++++++++++++-
fs/btrfs/volumes.c | 27 +++++++++++++++++++++++++++
fs/btrfs/volumes.h | 1 +
4 files changed, 68 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index ca9149a..6f9d760 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1305,6 +1305,7 @@ struct btrfs_fs_info {
struct btrfs_root *fs_root;
struct btrfs_root *csum_root;
struct btrfs_root *quota_root;
+ struct btrfs_root *uuid_root;
/* the log root tree is a directory of all the other log roots */
struct btrfs_root *log_root_tree;
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 4904d7f..3c2bf74 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1499,6 +1499,9 @@ struct btrfs_root *btrfs_read_fs_root_no_name(struct
btrfs_fs_info *fs_info,
if (location->objectid == BTRFS_QUOTA_TREE_OBJECTID)
return fs_info->quota_root ? fs_info->quota_root :
ERR_PTR(-ENOENT);
+ if (location->objectid == BTRFS_UUID_TREE_OBJECTID)
+ return fs_info->uuid_root ? fs_info->uuid_root :
+ ERR_PTR(-ENOENT);
again:
spin_lock(&fs_info->fs_roots_radix_lock);
root = radix_tree_lookup(&fs_info->fs_roots_radix,
@@ -1955,6 +1958,10 @@ static void free_root_pointers(struct btrfs_fs_info
*info, int chunk_root)
free_extent_buffer(info->quota_root->node);
free_extent_buffer(info->quota_root->commit_root);
}
+ if (info->uuid_root) {
+ free_extent_buffer(info->uuid_root->node);
+ free_extent_buffer(info->uuid_root->commit_root);
+ }
info->tree_root->node = NULL;
info->tree_root->commit_root = NULL;
@@ -1968,6 +1975,10 @@ static void free_root_pointers(struct btrfs_fs_info
*info, int chunk_root)
info->quota_root->node = NULL;
info->quota_root->commit_root = NULL;
}
+ if (info->uuid_root) {
+ info->uuid_root->node = NULL;
+ info->uuid_root->commit_root = NULL;
+ }
if (chunk_root) {
free_extent_buffer(info->chunk_root->node);
@@ -2029,11 +2040,13 @@ int open_ctree(struct super_block *sb,
struct btrfs_root *chunk_root;
struct btrfs_root *dev_root;
struct btrfs_root *quota_root;
+ struct btrfs_root *uuid_root;
struct btrfs_root *log_tree_root;
int ret;
int err = -EINVAL;
int num_backups_tried = 0;
int backup_index = 0;
+ bool create_uuid_tree = false;
tree_root = fs_info->tree_root = btrfs_alloc_root(fs_info);
extent_root = fs_info->extent_root = btrfs_alloc_root(fs_info);
@@ -2041,9 +2054,10 @@ int open_ctree(struct super_block *sb,
chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info);
dev_root = fs_info->dev_root = btrfs_alloc_root(fs_info);
quota_root = fs_info->quota_root = btrfs_alloc_root(fs_info);
+ uuid_root = fs_info->uuid_root = btrfs_alloc_root(fs_info);
if (!tree_root || !extent_root || !csum_root ||
- !chunk_root || !dev_root || !quota_root) {
+ !chunk_root || !dev_root || !quota_root || !uuid_root) {
err = -ENOMEM;
goto fail;
}
@@ -2604,6 +2618,19 @@ retry_root_backup:
fs_info->pending_quota_state = 1;
}
+ ret = find_and_setup_root(tree_root, fs_info,
+ BTRFS_UUID_TREE_OBJECTID, uuid_root);
+ if (ret) {
+ if (ret != -ENOENT)
+ goto recovery_tree_root;
+
+ kfree(uuid_root);
+ uuid_root = fs_info->uuid_root = NULL;
+ create_uuid_tree = true;
+ } else {
+ uuid_root->track_dirty = 1;
+ }
+
fs_info->generation = generation;
fs_info->last_trans_committed = generation;
@@ -2788,6 +2815,17 @@ retry_root_backup:
return ret;
}
+ if (create_uuid_tree) {
+ pr_info("btrfs: creating UUID tree\n");
+ ret = btrfs_create_uuid_tree(fs_info);
+ if (ret) {
+ pr_warn("btrfs: failed to create the UUID tree %d\n",
+ ret);
+ close_ctree(tree_root);
+ return ret;
+ }
+ }
+
return 0;
fail_qgroup:
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index a191bac..e6f5b88 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -3427,6 +3427,33 @@ int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
return 0;
}
+int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_trans_handle *trans;
+ struct btrfs_root *tree_root = fs_info->tree_root;
+ struct btrfs_root *uuid_root;
+
+ /*
+ * 1 - root node
+ * 1 - root item
+ */
+ trans = btrfs_start_transaction(tree_root, 2);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+
+ uuid_root = btrfs_create_tree(trans, fs_info,
+ BTRFS_UUID_TREE_OBJECTID);
+ if (IS_ERR(uuid_root)) {
+ btrfs_abort_transaction(trans, tree_root,
+ PTR_ERR(uuid_root));
+ return PTR_ERR(uuid_root);
+ }
+
+ fs_info->uuid_root = uuid_root;
+ uuid_root->track_dirty = 1;
+
+ return btrfs_commit_transaction(trans, tree_root);
+}
/*
* shrinking a device means finding all of the device extents past
* the new size, and then following the back refs to the chunks.
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 845ccbb..3479532 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -295,6 +295,7 @@ int btrfs_resume_balance_async(struct btrfs_fs_info
*fs_info);
int btrfs_recover_balance(struct btrfs_fs_info *fs_info);
int btrfs_pause_balance(struct btrfs_fs_info *fs_info);
int btrfs_cancel_balance(struct btrfs_fs_info *fs_info);
+int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info);
int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
u64 *start, u64 *max_avail);
--
1.8.2.2
--
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