From 1cf03a68e791b1673bc4daaa88a0820f34f538f8 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Wed, 1 Apr 2020 17:07:52 -0400 Subject: ceph: convert mdsc->cap_dirty to a per-session list This is a per-sb list now, but that makes it difficult to tell when the cap is the last dirty one associated with the session. Switch this to be a per-session list, but continue using the mdsc->cap_dirty_lock to protect the lists. This list is only ever walked in ceph_flush_dirty_caps, so change that to walk the sessions array and then flush the caps for inodes on each session's list. If the auth cap ever changes while the inode has dirty caps, then move the inode to the appropriate session for the new auth_cap. Also, ensure that we never remove an auth cap while the inode is still on the s_cap_dirty list. Signed-off-by: Jeff Layton Reviewed-by: "Yan, Zheng" Signed-off-by: Ilya Dryomov --- fs/ceph/super.h | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) (limited to 'fs/ceph/super.h') diff --git a/fs/ceph/super.h b/fs/ceph/super.h index bb372859c0ad..3a95395a4217 100644 --- a/fs/ceph/super.h +++ b/fs/ceph/super.h @@ -351,9 +351,22 @@ struct ceph_inode_info { struct rb_root i_caps; /* cap list */ struct ceph_cap *i_auth_cap; /* authoritative cap, if any */ unsigned i_dirty_caps, i_flushing_caps; /* mask of dirtied fields */ - struct list_head i_dirty_item, i_flushing_item; /* protected by - * mdsc->cap_dirty_lock - */ + + /* + * Link to the the auth cap's session's s_cap_dirty list. s_cap_dirty + * is protected by the mdsc->cap_dirty_lock, but each individual item + * is also protected by the inode's i_ceph_lock. Walking s_cap_dirty + * requires the mdsc->cap_dirty_lock. List presence for an item can + * be tested under the i_ceph_lock. Changing anything requires both. + */ + struct list_head i_dirty_item; + + /* + * Link to session's s_cap_flushing list. Protected by + * mdsc->cap_dirty_lock. + */ + struct list_head i_flushing_item; + /* we need to track cap writeback on a per-cap-bit basis, to allow * overlapping, pipelined cap flushes to the mds. we can probably * reduce the tid to 8 bits if we're concerned about inode size. */ -- cgit v1.2.3-70-g09d2