Btrfs: fix memory leak of block group cache
While processing delayed refs, we may update block group's statistics
and attach it to cur_trans->dirty_bgs, and later writing dirty block
groups will process the list, which happens during
btrfs_commit_transaction().
For whatever reason, the transaction is aborted and dirty_bgs
is not processed in cleanup_transaction(), we end up with memory leak
of these dirty block group cache.
Since btrfs_start_dirty_block_groups() doesn't make it go to the commit
critical section, this also adds the cleanup work inside it.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 54bc8c7..754de24 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -4475,9 +4475,80 @@
return 0;
}
+static void btrfs_cleanup_bg_io(struct btrfs_block_group_cache *cache)
+{
+ struct inode *inode;
+
+ inode = cache->io_ctl.inode;
+ if (inode) {
+ invalidate_inode_pages2(inode->i_mapping);
+ BTRFS_I(inode)->generation = 0;
+ cache->io_ctl.inode = NULL;
+ iput(inode);
+ }
+ btrfs_put_block_group(cache);
+}
+
+void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *cur_trans,
+ struct btrfs_root *root)
+{
+ struct btrfs_block_group_cache *cache;
+
+ spin_lock(&cur_trans->dirty_bgs_lock);
+ while (!list_empty(&cur_trans->dirty_bgs)) {
+ cache = list_first_entry(&cur_trans->dirty_bgs,
+ struct btrfs_block_group_cache,
+ dirty_list);
+ if (!cache) {
+ btrfs_err(root->fs_info,
+ "orphan block group dirty_bgs list");
+ spin_unlock(&cur_trans->dirty_bgs_lock);
+ return;
+ }
+
+ if (!list_empty(&cache->io_list)) {
+ spin_unlock(&cur_trans->dirty_bgs_lock);
+ list_del_init(&cache->io_list);
+ btrfs_cleanup_bg_io(cache);
+ spin_lock(&cur_trans->dirty_bgs_lock);
+ }
+
+ list_del_init(&cache->dirty_list);
+ spin_lock(&cache->lock);
+ cache->disk_cache_state = BTRFS_DC_ERROR;
+ spin_unlock(&cache->lock);
+
+ spin_unlock(&cur_trans->dirty_bgs_lock);
+ btrfs_put_block_group(cache);
+ spin_lock(&cur_trans->dirty_bgs_lock);
+ }
+ spin_unlock(&cur_trans->dirty_bgs_lock);
+
+ while (!list_empty(&cur_trans->io_bgs)) {
+ cache = list_first_entry(&cur_trans->io_bgs,
+ struct btrfs_block_group_cache,
+ io_list);
+ if (!cache) {
+ btrfs_err(root->fs_info,
+ "orphan block group on io_bgs list");
+ return;
+ }
+
+ list_del_init(&cache->io_list);
+ spin_lock(&cache->lock);
+ cache->disk_cache_state = BTRFS_DC_ERROR;
+ spin_unlock(&cache->lock);
+ btrfs_cleanup_bg_io(cache);
+ }
+}
+
void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
struct btrfs_root *root)
{
+ btrfs_cleanup_dirty_bgs(cur_trans, root);
+ ASSERT(list_empty(&cur_trans->dirty_bgs));
+ ASSERT(list_empty(&cur_trans->io_bgs));
+
btrfs_destroy_delayed_refs(cur_trans, root);
cur_trans->state = TRANS_STATE_COMMIT_START;
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index f19a982..1a3237e 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -136,6 +136,8 @@
struct btrfs_fs_info *fs_info);
int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
+void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans,
+ struct btrfs_root *root);
void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans,
struct btrfs_root *root);
struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 665da8f..616c455 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3694,6 +3694,8 @@
goto again;
}
spin_unlock(&cur_trans->dirty_bgs_lock);
+ } else if (ret < 0) {
+ btrfs_cleanup_dirty_bgs(cur_trans, root);
}
btrfs_free_path(path);