From c74d79af9002a9cb179f7950a2c266f0de964abe Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Tue, 6 Oct 2020 12:24:19 -0400 Subject: ceph: comment cleanups and clarifications Signed-off-by: Jeff Layton Signed-off-by: Ilya Dryomov --- fs/ceph/caps.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'fs/ceph/caps.c') diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index 0874ac445cdc..5027bbdca419 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -1922,12 +1922,24 @@ void ceph_check_caps(struct ceph_inode_info *ci, int flags, retry: spin_lock(&ci->i_ceph_lock); retry_locked: + /* Caps wanted by virtue of active open files. */ file_wanted = __ceph_caps_file_wanted(ci); + + /* Caps which have active references against them */ used = __ceph_caps_used(ci); + + /* + * "issued" represents the current caps that the MDS wants us to have. + * "implemented" is the set that we have been granted, and includes the + * ones that have not yet been returned to the MDS (the "revoking" set, + * usually because they have outstanding references). + */ issued = __ceph_caps_issued(ci, &implemented); revoking = implemented & ~issued; want = file_wanted; + + /* The ones we currently want to retain (may be adjusted below) */ retain = file_wanted | used | CEPH_CAP_PIN; if (!mdsc->stopping && inode->i_nlink > 0) { if (file_wanted) { @@ -2005,6 +2017,10 @@ retry_locked: /* NOTE: no side-effects allowed, until we take s_mutex */ + /* + * If we have an auth cap, we don't need to consider any + * overlapping caps as used. + */ cap_used = used; if (ci->i_auth_cap && cap != ci->i_auth_cap) cap_used &= ~ci->i_auth_cap->issued; -- cgit v1.2.3