summaryrefslogtreecommitdiffstats
path: root/lib/ubsan.c
diff options
context:
space:
mode:
authorQu Wenruo <wqu@suse.com>2017-12-12 08:34:32 +0100
committerDavid Sterba <dsterba@suse.com>2018-03-31 01:41:14 +0200
commit43b18595d6603cb4197fb9b063915cd7802141a6 (patch)
treeca7fc2969398f5deec170c705f4602018ab28f2d /lib/ubsan.c
parentbtrfs: qgroup: Introduce function to convert META_PREALLOC into META_PERTRANS (diff)
downloadlinux-43b18595d6603cb4197fb9b063915cd7802141a6.tar.xz
linux-43b18595d6603cb4197fb9b063915cd7802141a6.zip
btrfs: qgroup: Use separate meta reservation type for delalloc
Before this patch, btrfs qgroup is mixing per-transcation meta rsv with preallocated meta rsv, making it quite easy to underflow qgroup meta reservation. Since we have the new qgroup meta rsv types, apply it to delalloc reservation. Now for delalloc, most of its reserved space will use META_PREALLOC qgroup rsv type. And for callers reducing outstanding extent like btrfs_finish_ordered_io(), they will convert corresponding META_PREALLOC reservation to META_PERTRANS. This is mainly due to the fact that current qgroup numbers will only be updated in btrfs_commit_transaction(), that's to say if we don't keep such placeholder reservation, we can exceed qgroup limitation. And for callers freeing outstanding extent in error handler, we will just free META_PREALLOC bytes. This behavior makes callers of btrfs_qgroup_release_meta() or btrfs_qgroup_convert_meta() to be aware of which type they are. So in this patch, btrfs_delalloc_release_metadata() and its callers get an extra parameter to info qgroup to do correct meta convert/release. The good news is, even we use the wrong type (convert or free), it won't cause obvious bug, as prealloc type is always in good shape, and the type only affects how per-trans meta is increased or not. So the worst case will be at most metadata limitation can be sometimes exceeded (no convert at all) or metadata limitation is reached too soon (no free at all). Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'lib/ubsan.c')
0 files changed, 0 insertions, 0 deletions