Commit 2a496a5b8b74 ("btrfs-progs: mkfs: precreate the uuid tree")
creates uuid tree at mkfs time.
However it doesn't populate uuid tree correctly nor just create an empty
root.
It uses create_tree(), which just copies the content of fs root,
containing meaningless INODE_ITEM:
v4.15 mkfs (no uuid tree creation) + kernel mount:
uuid tree key (UUID_TREE ROOT_ITEM 0)
leaf 30572544 items 1 free space 16250 generation 7 owner UUID_TREE
leaf 30572544 flags 0x1(WRITTEN) backref revision 1
fs uuid 33ecddef-fc86-481a-93ce-846b01c11376
chunk uuid 9e58f646-b0da-43ca-9c7d-8bbe3e120246
item 0 key (0x92457c59d31491be UUID_KEY_SUBVOL 0xef908b5e79aa76a1) itemoff 16275 itemsize 8
subvol_id 5
v4.19.1 mkfs (incorrect one), no kernel mount:
uuid tree key (UUID_TREE ROOT_ITEM 0)
leaf 30507008 items 2 free space 16061 generation 4 owner UUID_TREE
leaf 30507008 flags 0x1(WRITTEN) backref revision 1
fs uuid 162f5333-9b5d-4217-877c-ddaeaa79398e
chunk uuid 7bc2c5c6-a6d2-4eec-a513-142b549c6541
item 0 key (256 INODE_ITEM 0) itemoff 16123 itemsize 160
generation 3 transid 0 size 0 nbytes 16384
block group 0 mode 40755 links 1 uid 0 gid 0 rdev 0
sequence 0 flags 0x0(none)
item 1 key (256 INODE_REF 256) itemoff 16111 itemsize 12
index 0 namelen 2 name: ..
This patchset will fix it by populuating uuid tree properly:
(NOTE: due to tree-checker, kernel doesn't accept empty uuid tree, so we
can only fix it by populating uuid tree correctly)
w/ this patchset, no kernel mount:
uuid tree key (UUID_TREE ROOT_ITEM 0)
leaf 30507008 items 1 free space 16250 generation 4 owner UUID_TREE
leaf 30507008 flags 0x1(WRITTEN) backref revision 1
fs uuid ae53079e-dbbc-409b-a565-5326c7b27731
chunk uuid b5fb1bea-f20d-4af1-80f8-6ca3f0038d67
item 0 key (0x334ba6b032d89c07 UUID_KEY_SUBVOL 0x86cde09cb78bcca0) itemoff 16275 itemsize 8
subvol_id 5
For kernel, except tree-checker needs an non-empty uuid tree, both all
above behavior won't cause problem, but it's always better to keep a
good standardized behavior.
Furthermore, to avoid such problem from happening again, rename the
function create_tree() to create_empty_tree() and create_inode_tree(),
without an @root parameter to avoid such problem.
Fixes: 2a496a5b8b74 ("btrfs-progs: mkfs: precreate the uuid tree")
Signed-off-by: Qu Wenruo <wqu@xxxxxxxx>
---
disk-io.c | 4 ++
mkfs/common.c | 103 ++++++++++++++++++++++++++++++++++++++++++++++++++
mkfs/common.h | 3 ++
mkfs/main.c | 36 +-----------------
4 files changed, 112 insertions(+), 34 deletions(-)
diff --git a/disk-io.c b/disk-io.c
index 5fafa144c0d3..2cb7f2097fc9 100644
--- a/disk-io.c
+++ b/disk-io.c
@@ -694,6 +694,8 @@ void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
{
if (fs_info->quota_root)
free(fs_info->quota_root);
+ if (fs_info->uuid_root)
+ free(fs_info->uuid_root);
free(fs_info->tree_root);
free(fs_info->extent_root);
@@ -964,6 +966,8 @@ void btrfs_release_all_roots(struct btrfs_fs_info *fs_info)
free_extent_buffer(fs_info->log_root_tree->node);
if (fs_info->chunk_root)
free_extent_buffer(fs_info->chunk_root->node);
+ if (fs_info->uuid_root)
+ free_extent_buffer(fs_info->uuid_root->node);
}
static void free_map_lookup(struct cache_extent *ce)
diff --git a/mkfs/common.c b/mkfs/common.c
index f7e3badcf2b9..1f5e1d03a6e3 100644
--- a/mkfs/common.c
+++ b/mkfs/common.c
@@ -23,6 +23,7 @@
#include "disk-io.h"
#include "volumes.h"
#include "utils.h"
+#include "transaction.h"
#include "mkfs/common.h"
static u64 reference_root_table[] = {
@@ -822,4 +823,106 @@ int test_minimum_size(const char *file, u64 min_dev_size)
return 0;
}
+/*
+ * Create a tree with all its content copied from @source
+ *
+ * Caller must ensure @source only has one leaf.
+ */
+static int __create_tree(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 objectid)
+{
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ struct btrfs_key location;
+ struct btrfs_root_item root_item;
+ struct extent_buffer *tmp;
+ u8 uuid[BTRFS_UUID_SIZE] = {0};
+ int ret;
+
+ ASSERT(btrfs_header_level(root->node) == 0);
+
+ ret = btrfs_copy_root(trans, root, root->node, &tmp, objectid);
+ if (ret)
+ return ret;
+
+ memcpy(&root_item, &root->root_item, sizeof(root_item));
+ btrfs_set_root_bytenr(&root_item, tmp->start);
+ btrfs_set_root_level(&root_item, btrfs_header_level(tmp));
+ btrfs_set_root_generation(&root_item, trans->transid);
+ /* clear uuid and o/ctime of source tree */
+ memcpy(root_item.uuid, uuid, BTRFS_UUID_SIZE);
+ btrfs_set_stack_timespec_sec(&root_item.otime, 0);
+ btrfs_set_stack_timespec_sec(&root_item.ctime, 0);
+ free_extent_buffer(tmp);
+
+ location.objectid = objectid;
+ location.type = BTRFS_ROOT_ITEM_KEY;
+ location.offset = 0;
+ ret = btrfs_insert_root(trans, fs_info->tree_root,
+ &location, &root_item);
+
+ return ret;
+}
+
+/*
+ * Create an *EMPTY* tree
+ *
+ * Caller must ensure at the time of calling, csum tree is still empty
+ */
+static int create_empty_tree(struct btrfs_trans_handle *trans, u64 objectid)
+{
+ struct btrfs_root *csum_root = trans->fs_info->csum_root;
+
+ ASSERT(btrfs_header_level(csum_root->node) == 0 &&
+ btrfs_header_nritems(csum_root->node) == 0);
+ return __create_tree(trans, csum_root, objectid);
+}
+/*
+ * Create a tree containing an root inode
+ *
+ * Caller must ensure at the time of calling, fs tree only contains 2 items
+ * (one for INODE_ITEM and one for INODE_REF)
+ */
+int create_inode_tree(struct btrfs_trans_handle *trans, u64 objectid)
+{
+ struct btrfs_root *fs_root = trans->fs_info->fs_root;
+
+ ASSERT(btrfs_header_level(fs_root->node) == 0 &&
+ btrfs_header_nritems(fs_root->node) == 2);
+ return __create_tree(trans, fs_root, objectid);
+}
+
+int create_uuid_tree(struct btrfs_trans_handle *trans)
+{
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ struct btrfs_root *uuid_root = fs_info->uuid_root;
+ struct btrfs_key key;
+ int ret;
+
+ if (!uuid_root) {
+ ret = create_empty_tree(trans, BTRFS_UUID_TREE_OBJECTID);
+ if (ret < 0) {
+ errno = -ret;
+ error("failed to create uuid root: %m");
+ return ret;
+ }
+ key.objectid = BTRFS_UUID_TREE_OBJECTID;
+ key.type = BTRFS_ROOT_ITEM_KEY;
+ key.offset = 0;
+ uuid_root = btrfs_read_fs_root_no_cache(fs_info, &key);
+ if (IS_ERR(uuid_root)) {
+ errno = -PTR_ERR(uuid_root);
+ error("failed to read uuid root: %m");
+ return PTR_ERR(uuid_root);
+ }
+ fs_info->uuid_root = uuid_root;
+ }
+ ret = btrfs_uuid_tree_add(trans, fs_info->fs_root->root_item.uuid,
+ BTRFS_UUID_KEY_SUBVOL,
+ fs_info->fs_root->root_key.objectid);
+ if (ret < 0) {
+ errno = -ret;
+ error("failed to add uuid tree entry for fs root: %m");
+ }
+ return ret;
+}
diff --git a/mkfs/common.h b/mkfs/common.h
index 28912906d0a9..adb5d561c38d 100644
--- a/mkfs/common.h
+++ b/mkfs/common.h
@@ -75,4 +75,7 @@ int test_num_disk_vs_raid(u64 metadata_profile, u64 data_profile,
int test_status_for_mkfs(const char *file, bool force_overwrite);
int test_dev_for_mkfs(const char *file, int force_overwrite);
+int create_uuid_tree(struct btrfs_trans_handle *trans);
+int create_inode_tree(struct btrfs_trans_handle *trans, u64 objectid);
+
#endif
diff --git a/mkfs/main.c b/mkfs/main.c
index b6748f7fe853..ea3d1ae80e5e 100644
--- a/mkfs/main.c
+++ b/mkfs/main.c
@@ -309,38 +309,6 @@ static int create_raid_groups(struct btrfs_trans_handle *trans,
return ret;
}
-static int create_tree(struct btrfs_trans_handle *trans,
- struct btrfs_root *root, u64 objectid)
-{
- struct btrfs_key location;
- struct btrfs_root_item root_item;
- struct extent_buffer *tmp;
- u8 uuid[BTRFS_UUID_SIZE] = {0};
- int ret;
-
- ret = btrfs_copy_root(trans, root, root->node, &tmp, objectid);
- if (ret)
- return ret;
-
- memcpy(&root_item, &root->root_item, sizeof(root_item));
- btrfs_set_root_bytenr(&root_item, tmp->start);
- btrfs_set_root_level(&root_item, btrfs_header_level(tmp));
- btrfs_set_root_generation(&root_item, trans->transid);
- /* clear uuid and o/ctime of source tree */
- memcpy(root_item.uuid, uuid, BTRFS_UUID_SIZE);
- btrfs_set_stack_timespec_sec(&root_item.otime, 0);
- btrfs_set_stack_timespec_sec(&root_item.ctime, 0);
- free_extent_buffer(tmp);
-
- location.objectid = objectid;
- location.type = BTRFS_ROOT_ITEM_KEY;
- location.offset = 0;
- ret = btrfs_insert_root(trans, root->fs_info->tree_root,
- &location, &root_item);
-
- return ret;
-}
-
static void print_usage(int ret)
{
printf("Usage: mkfs.btrfs [options] dev [ dev ... ]\n");
@@ -1203,13 +1171,13 @@ raid_groups:
goto out;
}
- ret = create_tree(trans, root, BTRFS_DATA_RELOC_TREE_OBJECTID);
+ ret = create_inode_tree(trans, BTRFS_DATA_RELOC_TREE_OBJECTID);
if (ret) {
error("unable to create data reloc tree: %d", ret);
goto out;
}
- ret = create_tree(trans, root, BTRFS_UUID_TREE_OBJECTID);
+ ret = create_uuid_tree(trans);
if (ret)
warning(
"unable to create uuid tree, will be created after mount: %d", ret);
--
2.20.1
