diff options
author | Tejun Heo <tj@kernel.org> | 2019-08-26 09:06:53 -0700 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2019-08-27 09:22:38 -0600 |
commit | 34f8fe501f0624de115d087680c84000b5d9abc9 (patch) | |
tree | 7c21102bb603a5ac0519fcfded63f9df89c25736 /include | |
parent | 5b9cce4c7eb0696558dfd4946074ae1fb9d8f05d (diff) |
bdi: Add bdi->id
There currently is no way to universally identify and lookup a bdi
without holding a reference and pointer to it. This patch adds an
non-recycling bdi->id and implements bdi_get_by_id() which looks up
bdis by their ids. This will be used by memcg foreign inode flushing.
I left bdi_list alone for simplicity and because while rb_tree does
support rcu assignment it doesn't seem to guarantee lossless walk when
walk is racing aginst tree rebalance operations.
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/backing-dev-defs.h | 2 | ||||
-rw-r--r-- | include/linux/backing-dev.h | 1 |
2 files changed, 3 insertions, 0 deletions
diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h index 8fb740178d5d..1075f2552cfc 100644 --- a/include/linux/backing-dev-defs.h +++ b/include/linux/backing-dev-defs.h @@ -185,6 +185,8 @@ struct bdi_writeback { }; struct backing_dev_info { + u64 id; + struct rb_node rb_node; /* keyed by ->id */ struct list_head bdi_list; unsigned long ra_pages; /* max readahead in PAGE_SIZE units */ unsigned long io_pages; /* max allowed IO size */ diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 02650b1253a2..84cdcfbc763f 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -24,6 +24,7 @@ static inline struct backing_dev_info *bdi_get(struct backing_dev_info *bdi) return bdi; } +struct backing_dev_info *bdi_get_by_id(u64 id); void bdi_put(struct backing_dev_info *bdi); __printf(2, 3) |