From ee3441b49092000402748f5345ee0a3d4c8ac04e Mon Sep 17 00:00:00 2001 From: Jeff Mahoney Date: Tue, 9 Jul 2013 16:37:21 -0400 Subject: [PATCH] btrfs: fall back to global reservation when removing subvolumes I recently did some ENOSPC testing that involved filling the disk while create and removing snapshots in a loop. During the test cycle, I ran into an ENOSPC when trying to remove a snapshot, leaving the fs stuck in ENOSPC even after a umount/mount cycle. This patch allow subvolume removal to fall back onto the global block reservation in order to succeed when it would have failed otherwise. Signed-off-by: Jeff Mahoney Signed-off-by: Josef Bacik Signed-off-by: Chris Mason --- fs/btrfs/ctree.h | 2 +- fs/btrfs/extent-tree.c | 8 +++++++- fs/btrfs/ioctl.c | 7 ++++--- 3 files changed, 12 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index e795bf135e80..8cc03321a368 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -3175,7 +3175,7 @@ void btrfs_orphan_release_metadata(struct inode *inode); int btrfs_subvolume_reserve_metadata(struct btrfs_root *root, struct btrfs_block_rsv *rsv, int nitems, - u64 *qgroup_reserved); + u64 *qgroup_reserved, bool use_global_rsv); void btrfs_subvolume_release_metadata(struct btrfs_root *root, struct btrfs_block_rsv *rsv, u64 qgroup_reserved); diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 3e7e05e6156f..7bea4d2f85dc 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -4742,10 +4742,12 @@ void btrfs_orphan_release_metadata(struct inode *inode) int btrfs_subvolume_reserve_metadata(struct btrfs_root *root, struct btrfs_block_rsv *rsv, int items, - u64 *qgroup_reserved) + u64 *qgroup_reserved, + bool use_global_rsv) { u64 num_bytes; int ret; + struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv; if (root->fs_info->quota_enabled) { /* One for parent inode, two for dir entries */ @@ -4764,6 +4766,10 @@ int btrfs_subvolume_reserve_metadata(struct btrfs_root *root, BTRFS_BLOCK_GROUP_METADATA); ret = btrfs_block_rsv_add(root, rsv, num_bytes, BTRFS_RESERVE_FLUSH_ALL); + + if (ret == -ENOSPC && use_global_rsv) + ret = btrfs_block_rsv_migrate(global_rsv, rsv, num_bytes); + if (ret) { if (*qgroup_reserved) btrfs_qgroup_free(root, *qgroup_reserved); diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 238a05545ee2..841044b80658 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -396,7 +396,7 @@ static noinline int create_subvol(struct inode *dir, * of create_snapshot(). */ ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, - 7, &qgroup_reserved); + 7, &qgroup_reserved, false); if (ret) return ret; @@ -576,7 +576,8 @@ static int create_snapshot(struct btrfs_root *root, struct inode *dir, */ ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root, &pending_snapshot->block_rsv, 7, - &pending_snapshot->qgroup_reserved); + &pending_snapshot->qgroup_reserved, + false); if (ret) goto out; @@ -2174,7 +2175,7 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file, * ref/backref. */ err = btrfs_subvolume_reserve_metadata(root, &block_rsv, - 5, &qgroup_reserved); + 5, &qgroup_reserved, true); if (err) goto out_up_write;