From mboxrd@z Thu Jan 1 00:00:00 1970 From: liubo Subject: Re: [PATCH] btrfs progs: fix extra metadata chunk allocation in --mixed case Date: Fri, 06 May 2011 09:05:28 +0800 Message-ID: <4DC34958.8010301@cn.fujitsu.com> References: <1304604972-31585-1-git-send-email-sensille@gmx.net> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: chris.mason@oracle.com, linux-btrfs@vger.kernel.org, josef@redhat.com To: Arne Jansen Return-path: In-Reply-To: <1304604972-31585-1-git-send-email-sensille@gmx.net> List-ID: On 05/05/2011 10:16 PM, Arne Jansen wrote: > When creating a mixed fs with mkfs, an extra metadata chunk got allocated. > This is because btrfs_reserve_extent calls do_chunk_alloc for METADATA, > which in turn wasn't able to find the proper space_info, as __find_space_info > did a hard compare of the flags. It is now sufficient for the space_info to > include the proper flag. This reflects the change done to the kernel code > to support mixed chunks. > Also for a subsequent chunk allocation (which should not be hit in the mkfs > case), the chunk is now created with the flags from the space_info instead > of the requested flags. A better solution would be to pull the full changeset > for the mixed case from the kernel into the user mode (or, even better, share > the code) > > The additional chunk probably confused block_rsv calculation, which in turn > led to severeal ENOSPC Oopses. > Good catch! Reviewed-by: Liu Bo > Signed-off-by: Arne Jansen > --- > extent-tree.c | 7 ++++--- > 1 files changed, 4 insertions(+), 3 deletions(-) > > diff --git a/extent-tree.c b/extent-tree.c > index b2f9bb2..c6c77c6 100644 > --- a/extent-tree.c > +++ b/extent-tree.c > @@ -1735,7 +1735,7 @@ static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info, > struct btrfs_space_info *found; > list_for_each(cur, head) { > found = list_entry(cur, struct btrfs_space_info, list); > - if (found->flags == flags) > + if (found->flags & flags) > return found; > } > return NULL; > @@ -1812,7 +1812,8 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans, > thresh) > return 0; > > - ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, flags); > + ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, > + space_info->flags); > if (ret == -ENOSPC) { > space_info->full = 1; > return 0; > @@ -1820,7 +1821,7 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans, > > BUG_ON(ret); > > - ret = btrfs_make_block_group(trans, extent_root, 0, flags, > + ret = btrfs_make_block_group(trans, extent_root, 0, space_info->flags, > BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes); > BUG_ON(ret); > return 0;