diff mbox

Btrfs: update drop progress before stopping snapshot dropping

Message ID 1373903973-2904-1-git-send-email-jbacik@fusionio.com (mailing list archive)
State Accepted, archived
Headers show

Commit Message

Josef Bacik July 15, 2013, 3:59 p.m. UTC
Alex pointed out a problem and fix that exists in the drop one snapshot at a
time patch.  If we decide we need to exit for whatever reason (umount for
example) we will just exit the snapshot dropping without updating the drop
progress.  So the next time we go to resume we will BUG_ON() because we can't
find the extent we left off at because we never updated it.  This patch fixes
the problem.

Cc: stable@vger.kernel.org
Reported-by: Alex Lyakas <alex.btrfs@zadarastorage.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
---
 fs/btrfs/extent-tree.c |   14 ++++++++------
 1 files changed, 8 insertions(+), 6 deletions(-)

Comments

Alex Lyakas July 30, 2013, 7:14 a.m. UTC | #1
Thanks for posting that patch, Josef.

On Mon, Jul 15, 2013 at 6:59 PM, Josef Bacik <jbacik@fusionio.com> wrote:
>
> Alex pointed out a problem and fix that exists in the drop one snapshot at
> a
> time patch.  If we decide we need to exit for whatever reason (umount for
> example) we will just exit the snapshot dropping without updating the drop
> progress.  So the next time we go to resume we will BUG_ON() because we
> can't
> find the extent we left off at because we never updated it.  This patch
> fixes
> the problem.
>
> Cc: stable@vger.kernel.org
> Reported-by: Alex Lyakas <alex.btrfs@zadarastorage.com>
> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
> ---
>  fs/btrfs/extent-tree.c |   14 ++++++++------
>  1 files changed, 8 insertions(+), 6 deletions(-)
>
> diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
> index bc00b24..8c204e1 100644
> --- a/fs/btrfs/extent-tree.c
> +++ b/fs/btrfs/extent-tree.c
> @@ -7584,11 +7584,6 @@ int btrfs_drop_snapshot(struct btrfs_root *root,
>         wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
>
>         while (1) {
> -               if (!for_reloc && btrfs_need_cleaner_sleep(root)) {
> -                       pr_debug("btrfs: drop snapshot early exit\n");
> -                       err = -EAGAIN;
> -                       goto out_end_trans;
> -               }
>
>                 ret = walk_down_tree(trans, root, path, wc);
>                 if (ret < 0) {
> @@ -7616,7 +7611,8 @@ int btrfs_drop_snapshot(struct btrfs_root *root,
>                 }
>
>                 BUG_ON(wc->level == 0);
> -               if (btrfs_should_end_transaction(trans, tree_root)) {
> +               if (btrfs_should_end_transaction(trans, tree_root) ||
> +                   (!for_reloc && btrfs_need_cleaner_sleep(root))) {
>                         ret = btrfs_update_root(trans, tree_root,
>                                                 &root->root_key,
>                                                 root_item);
> @@ -7627,6 +7623,12 @@ int btrfs_drop_snapshot(struct btrfs_root *root,
>                         }
>
>                         btrfs_end_transaction_throttle(trans, tree_root);
> +                       if (!for_reloc && btrfs_need_cleaner_sleep(root))
> {
> +                               pr_debug("btrfs: drop snapshot early
> exit\n");
> +                               err = -EAGAIN;
> +                               goto out_free;
> +                       }
> +
>                         trans = btrfs_start_transaction(tree_root, 0);
>                         if (IS_ERR(trans)) {
>                                 err = PTR_ERR(trans);
> --
> 1.7.7.6
>
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diff mbox

Patch

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index bc00b24..8c204e1 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -7584,11 +7584,6 @@  int btrfs_drop_snapshot(struct btrfs_root *root,
 	wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
 
 	while (1) {
-		if (!for_reloc && btrfs_need_cleaner_sleep(root)) {
-			pr_debug("btrfs: drop snapshot early exit\n");
-			err = -EAGAIN;
-			goto out_end_trans;
-		}
 
 		ret = walk_down_tree(trans, root, path, wc);
 		if (ret < 0) {
@@ -7616,7 +7611,8 @@  int btrfs_drop_snapshot(struct btrfs_root *root,
 		}
 
 		BUG_ON(wc->level == 0);
-		if (btrfs_should_end_transaction(trans, tree_root)) {
+		if (btrfs_should_end_transaction(trans, tree_root) ||
+		    (!for_reloc && btrfs_need_cleaner_sleep(root))) {
 			ret = btrfs_update_root(trans, tree_root,
 						&root->root_key,
 						root_item);
@@ -7627,6 +7623,12 @@  int btrfs_drop_snapshot(struct btrfs_root *root,
 			}
 
 			btrfs_end_transaction_throttle(trans, tree_root);
+			if (!for_reloc && btrfs_need_cleaner_sleep(root)) {
+				pr_debug("btrfs: drop snapshot early exit\n");
+				err = -EAGAIN;
+				goto out_free;
+			}
+
 			trans = btrfs_start_transaction(tree_root, 0);
 			if (IS_ERR(trans)) {
 				err = PTR_ERR(trans);