From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Yan, Zheng" Subject: Re: [PATCH 3/3] mds: fix race between cap issue and revoke Date: Mon, 24 Jun 2013 16:16:30 +0800 Message-ID: <51C8005E.9020105@intel.com> References: <1372056089-11603-1-git-send-email-zheng.z.yan@intel.com> <1372056089-11603-3-git-send-email-zheng.z.yan@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mga14.intel.com ([143.182.124.37]:14615 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753129Ab3FXIQc (ORCPT ); Mon, 24 Jun 2013 04:16:32 -0400 In-Reply-To: <1372056089-11603-3-git-send-email-zheng.z.yan@intel.com> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: ceph-devel@vger.kernel.org Cc: sage@inktank.com, alex.elder@linaro.org This patch's title is wrong, please ignore it. Thanks Yan, Zheng On 06/24/2013 02:41 PM, Yan, Zheng wrote: > From: "Yan, Zheng" > > 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 > --- > fs/ceph/caps.c | 29 ++++++++++++++++++++--------- > 1 file changed, 20 insertions(+), 9 deletions(-) > > diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c > index a8c616b..9b8b1aa 100644 > --- a/fs/ceph/caps.c > +++ b/fs/ceph/caps.c > @@ -813,22 +813,28 @@ 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); > @@ -2491,6 +2497,11 @@ 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 >