aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2023-12-14 11:53:00 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2023-12-14 11:53:00 -0800
commitbdb2701f0b6822d711ec34968ccef70b73a91da7 (patch)
tree98520ebdf7acc0299fc9f0471fb0bc8b5403a160
parent829649443e78d85db0cff0c37cadb28fbb1a5f6f (diff)
parente85a0adacf170634878fffcbf34b725aff3f49ed (diff)
downloadlinux-bdb2701f0b6822d711ec34968ccef70b73a91da7.tar.gz
Merge tag 'for-6.7-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba: "Some fixes to quota accounting code, mostly around error handling and correctness: - free reserves on various error paths, after IO errors or transaction abort - don't clear reserved range at the folio release time, it'll be properly cleared after final write - fix integer overflow due to int used when passing around size of freed reservations - fix a regression in squota accounting that missed some cases with delayed refs" * tag 'for-6.7-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: ensure releasing squota reserve on head refs btrfs: don't clear qgroup reserved bit in release_folio btrfs: free qgroup pertrans reserve on transaction abort btrfs: fix qgroup_free_reserved_data int overflow btrfs: free qgroup reserve when ORDERED_IOERR is set
-rw-r--r--fs/btrfs/delalloc-space.c2
-rw-r--r--fs/btrfs/disk-io.c28
-rw-r--r--fs/btrfs/extent-tree.c48
-rw-r--r--fs/btrfs/extent_io.c3
-rw-r--r--fs/btrfs/file.c2
-rw-r--r--fs/btrfs/inode.c16
-rw-r--r--fs/btrfs/ordered-data.c11
-rw-r--r--fs/btrfs/qgroup.c44
-rw-r--r--fs/btrfs/qgroup.h7
-rw-r--r--fs/btrfs/transaction.c2
-rw-r--r--fs/btrfs/transaction.h3
11 files changed, 116 insertions, 50 deletions
diff --git a/fs/btrfs/delalloc-space.c b/fs/btrfs/delalloc-space.c
index 51453d4928fa40..2833e8ef4c098f 100644
--- a/fs/btrfs/delalloc-space.c
+++ b/fs/btrfs/delalloc-space.c
@@ -199,7 +199,7 @@ void btrfs_free_reserved_data_space(struct btrfs_inode *inode,
start = round_down(start, fs_info->sectorsize);
btrfs_free_reserved_data_space_noquota(fs_info, len);
- btrfs_qgroup_free_data(inode, reserved, start, len);
+ btrfs_qgroup_free_data(inode, reserved, start, len, NULL);
}
/*
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index bbcc3df776461f..62cb97f7c94fa2 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -4799,6 +4799,32 @@ void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *cur_trans,
}
}
+static void btrfs_free_all_qgroup_pertrans(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_root *gang[8];
+ int i;
+ int ret;
+
+ spin_lock(&fs_info->fs_roots_radix_lock);
+ while (1) {
+ ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix,
+ (void **)gang, 0,
+ ARRAY_SIZE(gang),
+ BTRFS_ROOT_TRANS_TAG);
+ if (ret == 0)
+ break;
+ for (i = 0; i < ret; i++) {
+ struct btrfs_root *root = gang[i];
+
+ btrfs_qgroup_free_meta_all_pertrans(root);
+ radix_tree_tag_clear(&fs_info->fs_roots_radix,
+ (unsigned long)root->root_key.objectid,
+ BTRFS_ROOT_TRANS_TAG);
+ }
+ }
+ spin_unlock(&fs_info->fs_roots_radix_lock);
+}
+
void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
struct btrfs_fs_info *fs_info)
{
@@ -4827,6 +4853,8 @@ void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
EXTENT_DIRTY);
btrfs_destroy_pinned_extent(fs_info, &cur_trans->pinned_extents);
+ btrfs_free_all_qgroup_pertrans(fs_info);
+
cur_trans->state =TRANS_STATE_COMPLETED;
wake_up(&cur_trans->commit_wait);
}
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 0455935ff55880..01423670bc8a2b 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1547,6 +1547,23 @@ out:
return ret;
}
+static void free_head_ref_squota_rsv(struct btrfs_fs_info *fs_info,
+ struct btrfs_delayed_ref_head *href)
+{
+ u64 root = href->owning_root;
+
+ /*
+ * Don't check must_insert_reserved, as this is called from contexts
+ * where it has already been unset.
+ */
+ if (btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_SIMPLE ||
+ !href->is_data || !is_fstree(root))
+ return;
+
+ btrfs_qgroup_free_refroot(fs_info, root, href->reserved_bytes,
+ BTRFS_QGROUP_RSV_DATA);
+}
+
static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
struct btrfs_delayed_ref_head *href,
struct btrfs_delayed_ref_node *node,
@@ -1569,7 +1586,6 @@ static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
struct btrfs_squota_delta delta = {
.root = href->owning_root,
.num_bytes = node->num_bytes,
- .rsv_bytes = href->reserved_bytes,
.is_data = true,
.is_inc = true,
.generation = trans->transid,
@@ -1586,11 +1602,9 @@ static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
flags, ref->objectid,
ref->offset, &key,
node->ref_mod, href->owning_root);
+ free_head_ref_squota_rsv(trans->fs_info, href);
if (!ret)
ret = btrfs_record_squota_delta(trans->fs_info, &delta);
- else
- btrfs_qgroup_free_refroot(trans->fs_info, delta.root,
- delta.rsv_bytes, BTRFS_QGROUP_RSV_DATA);
} else if (node->action == BTRFS_ADD_DELAYED_REF) {
ret = __btrfs_inc_extent_ref(trans, node, parent, ref->root,
ref->objectid, ref->offset,
@@ -1742,7 +1756,6 @@ static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
struct btrfs_squota_delta delta = {
.root = href->owning_root,
.num_bytes = fs_info->nodesize,
- .rsv_bytes = 0,
.is_data = false,
.is_inc = true,
.generation = trans->transid,
@@ -1774,8 +1787,10 @@ static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
int ret = 0;
if (TRANS_ABORTED(trans)) {
- if (insert_reserved)
+ if (insert_reserved) {
btrfs_pin_extent(trans, node->bytenr, node->num_bytes, 1);
+ free_head_ref_squota_rsv(trans->fs_info, href);
+ }
return 0;
}
@@ -1871,6 +1886,8 @@ u64 btrfs_cleanup_ref_head_accounting(struct btrfs_fs_info *fs_info,
struct btrfs_delayed_ref_root *delayed_refs,
struct btrfs_delayed_ref_head *head)
{
+ u64 ret = 0;
+
/*
* We had csum deletions accounted for in our delayed refs rsv, we need
* to drop the csum leaves for this update from our delayed_refs_rsv.
@@ -1885,14 +1902,13 @@ u64 btrfs_cleanup_ref_head_accounting(struct btrfs_fs_info *fs_info,
btrfs_delayed_refs_rsv_release(fs_info, 0, nr_csums);
- return btrfs_calc_delayed_ref_csum_bytes(fs_info, nr_csums);
+ ret = btrfs_calc_delayed_ref_csum_bytes(fs_info, nr_csums);
}
- if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE &&
- head->must_insert_reserved && head->is_data)
- btrfs_qgroup_free_refroot(fs_info, head->owning_root,
- head->reserved_bytes, BTRFS_QGROUP_RSV_DATA);
+ /* must_insert_reserved can be set only if we didn't run the head ref. */
+ if (head->must_insert_reserved)
+ free_head_ref_squota_rsv(fs_info, head);
- return 0;
+ return ret;
}
static int cleanup_ref_head(struct btrfs_trans_handle *trans,
@@ -2033,6 +2049,12 @@ static int btrfs_run_delayed_refs_for_head(struct btrfs_trans_handle *trans,
* spin lock.
*/
must_insert_reserved = locked_ref->must_insert_reserved;
+ /*
+ * Unsetting this on the head ref relinquishes ownership of
+ * the rsv_bytes, so it is critical that every possible code
+ * path from here forward frees all reserves including qgroup
+ * reserve.
+ */
locked_ref->must_insert_reserved = false;
extent_op = locked_ref->extent_op;
@@ -3292,7 +3314,6 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
struct btrfs_squota_delta delta = {
.root = delayed_ref_root,
.num_bytes = num_bytes,
- .rsv_bytes = 0,
.is_data = is_data,
.is_inc = false,
.generation = btrfs_extent_generation(leaf, ei),
@@ -4937,7 +4958,6 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
.root = root_objectid,
.num_bytes = ins->offset,
.generation = trans->transid,
- .rsv_bytes = 0,
.is_data = true,
.is_inc = true,
};
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index e6230a6ffa9859..8f724c54fc8e9c 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2302,7 +2302,8 @@ static int try_release_extent_state(struct extent_io_tree *tree,
ret = 0;
} else {
u32 clear_bits = ~(EXTENT_LOCKED | EXTENT_NODATASUM |
- EXTENT_DELALLOC_NEW | EXTENT_CTLBITS);
+ EXTENT_DELALLOC_NEW | EXTENT_CTLBITS |
+ EXTENT_QGROUP_RESERVED);
/*
* At this point we can safely clear everything except the
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index f47731c45bb504..32611a4edd6b23 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -3192,7 +3192,7 @@ static long btrfs_fallocate(struct file *file, int mode,
qgroup_reserved -= range->len;
} else if (qgroup_reserved > 0) {
btrfs_qgroup_free_data(BTRFS_I(inode), data_reserved,
- range->start, range->len);
+ range->start, range->len, NULL);
qgroup_reserved -= range->len;
}
list_del(&range->list);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 9f5a9894f88f49..fb3c3f43c3fa40 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -688,7 +688,7 @@ out:
* And at reserve time, it's always aligned to page size, so
* just free one page here.
*/
- btrfs_qgroup_free_data(inode, NULL, 0, PAGE_SIZE);
+ btrfs_qgroup_free_data(inode, NULL, 0, PAGE_SIZE, NULL);
btrfs_free_path(path);
btrfs_end_transaction(trans);
return ret;
@@ -5132,7 +5132,7 @@ static void evict_inode_truncate_pages(struct inode *inode)
*/
if (state_flags & EXTENT_DELALLOC)
btrfs_qgroup_free_data(BTRFS_I(inode), NULL, start,
- end - start + 1);
+ end - start + 1, NULL);
clear_extent_bit(io_tree, start, end,
EXTENT_CLEAR_ALL_BITS | EXTENT_DO_ACCOUNTING,
@@ -8059,7 +8059,7 @@ next:
* reserved data space.
* Since the IO will never happen for this page.
*/
- btrfs_qgroup_free_data(inode, NULL, cur, range_end + 1 - cur);
+ btrfs_qgroup_free_data(inode, NULL, cur, range_end + 1 - cur, NULL);
if (!inode_evicting) {
clear_extent_bit(tree, cur, range_end, EXTENT_LOCKED |
EXTENT_DELALLOC | EXTENT_UPTODATE |
@@ -9491,7 +9491,7 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent(
struct btrfs_path *path;
u64 start = ins->objectid;
u64 len = ins->offset;
- int qgroup_released;
+ u64 qgroup_released = 0;
int ret;
memset(&stack_fi, 0, sizeof(stack_fi));
@@ -9504,9 +9504,9 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent(
btrfs_set_stack_file_extent_compression(&stack_fi, BTRFS_COMPRESS_NONE);
/* Encryption and other encoding is reserved and all 0 */
- qgroup_released = btrfs_qgroup_release_data(inode, file_offset, len);
- if (qgroup_released < 0)
- return ERR_PTR(qgroup_released);
+ ret = btrfs_qgroup_release_data(inode, file_offset, len, &qgroup_released);
+ if (ret < 0)
+ return ERR_PTR(ret);
if (trans) {
ret = insert_reserved_file_extent(trans, inode,
@@ -10401,7 +10401,7 @@ out_delalloc_release:
btrfs_delalloc_release_metadata(inode, disk_num_bytes, ret < 0);
out_qgroup_free_data:
if (ret < 0)
- btrfs_qgroup_free_data(inode, data_reserved, start, num_bytes);
+ btrfs_qgroup_free_data(inode, data_reserved, start, num_bytes, NULL);
out_free_data_space:
/*
* If btrfs_reserve_extent() succeeded, then we already decremented
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 574e8a55e24a2b..a82e1417c4d278 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -152,11 +152,12 @@ static struct btrfs_ordered_extent *alloc_ordered_extent(
{
struct btrfs_ordered_extent *entry;
int ret;
+ u64 qgroup_rsv = 0;
if (flags &
((1 << BTRFS_ORDERED_NOCOW) | (1 << BTRFS_ORDERED_PREALLOC))) {
/* For nocow write, we can release the qgroup rsv right now */
- ret = btrfs_qgroup_free_data(inode, NULL, file_offset, num_bytes);
+ ret = btrfs_qgroup_free_data(inode, NULL, file_offset, num_bytes, &qgroup_rsv);
if (ret < 0)
return ERR_PTR(ret);
} else {
@@ -164,7 +165,7 @@ static struct btrfs_ordered_extent *alloc_ordered_extent(
* The ordered extent has reserved qgroup space, release now
* and pass the reserved number for qgroup_record to free.
*/
- ret = btrfs_qgroup_release_data(inode, file_offset, num_bytes);
+ ret = btrfs_qgroup_release_data(inode, file_offset, num_bytes, &qgroup_rsv);
if (ret < 0)
return ERR_PTR(ret);
}
@@ -182,7 +183,7 @@ static struct btrfs_ordered_extent *alloc_ordered_extent(
entry->inode = igrab(&inode->vfs_inode);
entry->compress_type = compress_type;
entry->truncated_len = (u64)-1;
- entry->qgroup_rsv = ret;
+ entry->qgroup_rsv = qgroup_rsv;
entry->flags = flags;
refcount_set(&entry->refs, 1);
init_waitqueue_head(&entry->wait);
@@ -599,7 +600,9 @@ void btrfs_remove_ordered_extent(struct btrfs_inode *btrfs_inode,
release = entry->disk_num_bytes;
else
release = entry->num_bytes;
- btrfs_delalloc_release_metadata(btrfs_inode, release, false);
+ btrfs_delalloc_release_metadata(btrfs_inode, release,
+ test_bit(BTRFS_ORDERED_IOERR,
+ &entry->flags));
}
percpu_counter_add_batch(&fs_info->ordered_bytes, -entry->num_bytes,
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index ce446d9d7f23da..e46774e8f49fd6 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -4057,13 +4057,14 @@ int btrfs_qgroup_reserve_data(struct btrfs_inode *inode,
/* Free ranges specified by @reserved, normally in error path */
static int qgroup_free_reserved_data(struct btrfs_inode *inode,
- struct extent_changeset *reserved, u64 start, u64 len)
+ struct extent_changeset *reserved,
+ u64 start, u64 len, u64 *freed_ret)
{
struct btrfs_root *root = inode->root;
struct ulist_node *unode;
struct ulist_iterator uiter;
struct extent_changeset changeset;
- int freed = 0;
+ u64 freed = 0;
int ret;
extent_changeset_init(&changeset);
@@ -4104,7 +4105,9 @@ static int qgroup_free_reserved_data(struct btrfs_inode *inode,
}
btrfs_qgroup_free_refroot(root->fs_info, root->root_key.objectid, freed,
BTRFS_QGROUP_RSV_DATA);
- ret = freed;
+ if (freed_ret)
+ *freed_ret = freed;
+ ret = 0;
out:
extent_changeset_release(&changeset);
return ret;
@@ -4112,7 +4115,7 @@ out:
static int __btrfs_qgroup_release_data(struct btrfs_inode *inode,
struct extent_changeset *reserved, u64 start, u64 len,
- int free)
+ u64 *released, int free)
{
struct extent_changeset changeset;
int trace_op = QGROUP_RELEASE;
@@ -4128,7 +4131,7 @@ static int __btrfs_qgroup_release_data(struct btrfs_inode *inode,
/* In release case, we shouldn't have @reserved */
WARN_ON(!free && reserved);
if (free && reserved)
- return qgroup_free_reserved_data(inode, reserved, start, len);
+ return qgroup_free_reserved_data(inode, reserved, start, len, released);
extent_changeset_init(&changeset);
ret = clear_record_extent_bits(&inode->io_tree, start, start + len -1,
EXTENT_QGROUP_RESERVED, &changeset);
@@ -4143,7 +4146,8 @@ static int __btrfs_qgroup_release_data(struct btrfs_inode *inode,
btrfs_qgroup_free_refroot(inode->root->fs_info,
inode->root->root_key.objectid,
changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
- ret = changeset.bytes_changed;
+ if (released)
+ *released = changeset.bytes_changed;
out:
extent_changeset_release(&changeset);
return ret;
@@ -4162,9 +4166,10 @@ out:
* NOTE: This function may sleep for memory allocation.
*/
int btrfs_qgroup_free_data(struct btrfs_inode *inode,
- struct extent_changeset *reserved, u64 start, u64 len)
+ struct extent_changeset *reserved,
+ u64 start, u64 len, u64 *freed)
{
- return __btrfs_qgroup_release_data(inode, reserved, start, len, 1);
+ return __btrfs_qgroup_release_data(inode, reserved, start, len, freed, 1);
}
/*
@@ -4182,9 +4187,9 @@ int btrfs_qgroup_free_data(struct btrfs_inode *inode,
*
* NOTE: This function may sleep for memory allocation.
*/
-int btrfs_qgroup_release_data(struct btrfs_inode *inode, u64 start, u64 len)
+int btrfs_qgroup_release_data(struct btrfs_inode *inode, u64 start, u64 len, u64 *released)
{
- return __btrfs_qgroup_release_data(inode, NULL, start, len, 0);
+ return __btrfs_qgroup_release_data(inode, NULL, start, len, released, 0);
}
static void add_root_meta_rsv(struct btrfs_root *root, int num_bytes,
@@ -4332,8 +4337,9 @@ static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
qgroup_rsv_release(fs_info, qgroup, num_bytes,
BTRFS_QGROUP_RSV_META_PREALLOC);
- qgroup_rsv_add(fs_info, qgroup, num_bytes,
- BTRFS_QGROUP_RSV_META_PERTRANS);
+ if (!sb_rdonly(fs_info->sb))
+ qgroup_rsv_add(fs_info, qgroup, num_bytes,
+ BTRFS_QGROUP_RSV_META_PERTRANS);
list_for_each_entry(glist, &qgroup->groups, next_group)
qgroup_iterator_add(&qgroup_list, glist->group);
@@ -4655,6 +4661,17 @@ void btrfs_qgroup_destroy_extent_records(struct btrfs_transaction *trans)
*root = RB_ROOT;
}
+void btrfs_free_squota_rsv(struct btrfs_fs_info *fs_info, u64 root, u64 rsv_bytes)
+{
+ if (btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_SIMPLE)
+ return;
+
+ if (!is_fstree(root))
+ return;
+
+ btrfs_qgroup_free_refroot(fs_info, root, rsv_bytes, BTRFS_QGROUP_RSV_DATA);
+}
+
int btrfs_record_squota_delta(struct btrfs_fs_info *fs_info,
struct btrfs_squota_delta *delta)
{
@@ -4699,8 +4716,5 @@ int btrfs_record_squota_delta(struct btrfs_fs_info *fs_info,
out:
spin_unlock(&fs_info->qgroup_lock);
- if (!ret && delta->rsv_bytes)
- btrfs_qgroup_free_refroot(fs_info, root, delta->rsv_bytes,
- BTRFS_QGROUP_RSV_DATA);
return ret;
}
diff --git a/fs/btrfs/qgroup.h b/fs/btrfs/qgroup.h
index 855a4f97876185..be18c862e64ede 100644
--- a/fs/btrfs/qgroup.h
+++ b/fs/btrfs/qgroup.h
@@ -274,8 +274,6 @@ struct btrfs_squota_delta {
u64 root;
/* The number of bytes in the extent being counted. */
u64 num_bytes;
- /* The number of bytes reserved for this extent. */
- u64 rsv_bytes;
/* The generation the extent was created in. */
u64 generation;
/* Whether we are using or freeing the extent. */
@@ -358,10 +356,10 @@ int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
/* New io_tree based accurate qgroup reserve API */
int btrfs_qgroup_reserve_data(struct btrfs_inode *inode,
struct extent_changeset **reserved, u64 start, u64 len);
-int btrfs_qgroup_release_data(struct btrfs_inode *inode, u64 start, u64 len);
+int btrfs_qgroup_release_data(struct btrfs_inode *inode, u64 start, u64 len, u64 *released);
int btrfs_qgroup_free_data(struct btrfs_inode *inode,
struct extent_changeset *reserved, u64 start,
- u64 len);
+ u64 len, u64 *freed);
int btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
enum btrfs_qgroup_rsv_type type, bool enforce);
int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
@@ -422,6 +420,7 @@ int btrfs_qgroup_trace_subtree_after_cow(struct btrfs_trans_handle *trans,
struct btrfs_root *root, struct extent_buffer *eb);
void btrfs_qgroup_destroy_extent_records(struct btrfs_transaction *trans);
bool btrfs_check_quota_leak(struct btrfs_fs_info *fs_info);
+void btrfs_free_squota_rsv(struct btrfs_fs_info *fs_info, u64 root, u64 rsv_bytes);
int btrfs_record_squota_delta(struct btrfs_fs_info *fs_info,
struct btrfs_squota_delta *delta);
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index bfc0eb5e3b7c22..5b3333ceef0481 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -37,8 +37,6 @@
static struct kmem_cache *btrfs_trans_handle_cachep;
-#define BTRFS_ROOT_TRANS_TAG 0
-
/*
* Transaction states and transitions
*
diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h
index 18c4f6e83b7883..2bf8bbdfd0b38b 100644
--- a/fs/btrfs/transaction.h
+++ b/fs/btrfs/transaction.h
@@ -12,6 +12,9 @@
#include "ctree.h"
#include "misc.h"
+/* Radix-tree tag for roots that are part of the trasaction. */
+#define BTRFS_ROOT_TRANS_TAG 0
+
enum btrfs_trans_state {
TRANS_STATE_RUNNING,
TRANS_STATE_COMMIT_PREP,