On 10/23/2012 09:55 PM, Jan Schmidt wrote:
> Tree mod log treated old root buffers as always empty buffers when starting
> the rewind operations. However, the old root may still be part of the
> current tree at a lower level, with still some valid entries.
>
Reviewed-by: Liu Bo <bo.li.liu@xxxxxxxxxx>
Tested-by: Liu Bo <bo.li.liu@xxxxxxxxxx>
thanks,
liubo
> Signed-off-by: Jan Schmidt <list.btrfs@xxxxxxxxxxxxx>
> ---
> fs/btrfs/ctree.c | 16 ++++++++++++++--
> 1 files changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
> index e6b75cc..1b60c56 100644
> --- a/fs/btrfs/ctree.c
> +++ b/fs/btrfs/ctree.c
> @@ -1239,6 +1239,7 @@ get_old_root(struct btrfs_root *root, u64 time_seq)
> struct tree_mod_root *old_root = NULL;
> u64 old_generation = 0;
> u64 logical;
> + u32 blocksize;
>
> eb = btrfs_read_lock_root_node(root);
> tm = __tree_mod_log_oldest_root(root->fs_info, root, time_seq);
> @@ -1254,10 +1255,21 @@ get_old_root(struct btrfs_root *root, u64 time_seq)
> }
>
> tm = tree_mod_log_search(root->fs_info, logical, time_seq);
> - if (old_root)
> + if (old_root && tm && tm->op != MOD_LOG_KEY_REMOVE_WHILE_FREEING) {
> + blocksize = btrfs_level_size(root, old_root->level);
> + eb = read_tree_block(root, logical, blocksize, 0);
> + if (!eb) {
> + pr_warn("btrfs: failed to read tree block %llu from get_old_root\n",
> + logical);
> + WARN_ON(1);
> + } else {
> + eb = btrfs_clone_extent_buffer(eb);
> + }
> + } else if (old_root) {
> eb = alloc_dummy_extent_buffer(logical, root->nodesize);
> - else
> + } else {
> eb = btrfs_clone_extent_buffer(root->node);
> + }
> btrfs_tree_read_unlock(root->node);
> free_extent_buffer(root->node);
> if (!eb)
>
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
