From 6ee6b95373dfa1d0a4c9bc76689ec10a60c1d6f2 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Tue, 2 Jul 2013 12:40:21 +0800 Subject: ceph: fix race between cap issue and revoke If we receive new caps from the auth MDS and the non-auth MDS is revoking the newly issued caps, we should release the caps from the non-auth MDS. The scenario is filelock's state changes from SYNC to LOCK. Non-auth MDS revokes Fc cap, the client gets Fc cap from the auth MDS at the same time. Signed-off-by: Yan, Zheng Reviewed-by: Sage Weil --- fs/ceph/caps.c | 29 ++++++++++++++++++++--------- 1 file changed, 20 insertions(+), 9 deletions(-) (limited to 'fs') diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index 7045a8dfaad..25442b40c25 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -806,22 +806,28 @@ int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int touch) /* * Return true if mask caps are currently being revoked by an MDS. */ -int ceph_caps_revoking(struct ceph_inode_info *ci, int mask) +int __ceph_caps_revoking_other(struct ceph_inode_info *ci, + struct ceph_cap *ocap, int mask) { - struct inode *inode = &ci->vfs_inode; struct ceph_cap *cap; struct rb_node *p; - int ret = 0; - spin_lock(&ci->i_ceph_lock); for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) { cap = rb_entry(p, struct ceph_cap, ci_node); - if (__cap_is_valid(cap) && - (cap->implemented & ~cap->issued & mask)) { - ret = 1; - break; - } + if (cap != ocap && __cap_is_valid(cap) && + (cap->implemented & ~cap->issued & mask)) + return 1; } + return 0; +} + +int ceph_caps_revoking(struct ceph_inode_info *ci, int mask) +{ + struct inode *inode = &ci->vfs_inode; + int ret; + + spin_lock(&ci->i_ceph_lock); + ret = __ceph_caps_revoking_other(ci, NULL, mask); spin_unlock(&ci->i_ceph_lock); dout("ceph_caps_revoking %p %s = %d\n", inode, ceph_cap_string(mask), ret); @@ -2488,6 +2494,11 @@ static void handle_cap_grant(struct inode *inode, struct ceph_mds_caps *grant, } else { dout("grant: %s -> %s\n", ceph_cap_string(cap->issued), ceph_cap_string(newcaps)); + /* non-auth MDS is revoking the newly grant caps ? */ + if (cap == ci->i_auth_cap && + __ceph_caps_revoking_other(ci, cap, newcaps)) + check_caps = 2; + cap->issued = newcaps; cap->implemented |= newcaps; /* add bits only, to * avoid stepping on a -- cgit v1.2.3