cluster/ec: Fix lk-owner set race in ec_unlock

Problem:
Rename does two locks. There is a case where when it tries to unlock it sends
xattrop of the directory with new version, callback of these two xattrops can
be picked up by two separate epoll threads. Both of them will try to set the
lk-owner for unlock in parallel on the same frame so one of these unlocks will
fail because the lk-owner doesn't match.

Fix:
Specify the lk-owner which will be set on inodelk frame which will not be over
written by any other thread/operation.

BUG: 1402710
Change-Id: I666ffc931440dc5253d72df666efe0ef1d73f99a
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Reviewed-on: http://review.gluster.org/16074
Reviewed-by: Xavier Hernandez <xhernandez@datalab.es>
Smoke: Gluster Build System <jenkins@build.gluster.org>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>

1 files changed, 14 insertions, 10 deletions

diff --git a/xlators/cluster/ec/src/ec-locks.c b/xlators/cluster/ec/src/ec-locks.c
index ed835f1aadc..bd525723ddf 100644
--- a/xlators/cluster/ec/src/ec-locks.c
+++ b/xlators/cluster/ec/src/ec-locks.c
@@ -608,12 +608,14 @@ int32_t ec_manager_inodelk(ec_fop_data_t * fop, int32_t state)
                         flock.l_owner.len = 0;
 
                         if (fop->id == GF_FOP_INODELK) {
-                            ec_inodelk(fop->frame, fop->xl, mask, 1,
+                            ec_inodelk(fop->frame, fop->xl,
+                                       &fop->frame->root->lk_owner, mask, 1,
                                        ec_lock_unlocked, NULL, fop->str[0],
                                        &fop->loc[0], F_SETLK, &flock,
                                        fop->xdata);
                         } else {
-                            ec_finodelk(fop->frame, fop->xl, mask, 1,
+                            ec_finodelk(fop->frame, fop->xl,
+                                        &fop->frame->root->lk_owner, mask, 1,
                                         ec_lock_unlocked, NULL, fop->str[0],
                                         fop->fd, F_SETLK, &flock, fop->xdata);
                         }
@@ -692,10 +694,10 @@ int32_t ec_manager_inodelk(ec_fop_data_t * fop, int32_t state)
     }
 }
 
-void ec_inodelk(call_frame_t * frame, xlator_t * this, uintptr_t target,
-                int32_t minimum, fop_inodelk_cbk_t func, void * data,
-                const char * volume, loc_t * loc, int32_t cmd,
-                struct gf_flock * flock, dict_t * xdata)
+void ec_inodelk (call_frame_t *frame, xlator_t *this, gf_lkowner_t *owner,
+                 uintptr_t target, int32_t minimum, fop_inodelk_cbk_t func,
+                 void *data, const char *volume, loc_t *loc, int32_t cmd,
+                 struct gf_flock *flock, dict_t *xdata)
 {
     ec_cbk_t callback = { .inodelk = func };
     ec_fop_data_t * fop = NULL;
@@ -715,6 +717,7 @@ void ec_inodelk(call_frame_t * frame, xlator_t * this, uintptr_t target,
     }
 
     fop->int32 = cmd;
+    ec_owner_copy (fop->frame, owner);
 
     if (volume != NULL) {
         fop->str[0] = gf_strdup(volume);
@@ -828,10 +831,10 @@ void ec_wind_finodelk(ec_t * ec, ec_fop_data_t * fop, int32_t idx)
                       fop->xdata);
 }
 
-void ec_finodelk(call_frame_t * frame, xlator_t * this, uintptr_t target,
-                 int32_t minimum, fop_finodelk_cbk_t func, void * data,
-                 const char * volume, fd_t * fd, int32_t cmd,
-                 struct gf_flock * flock, dict_t * xdata)
+void ec_finodelk(call_frame_t *frame, xlator_t *this, gf_lkowner_t *owner,
+                 uintptr_t target, int32_t minimum, fop_finodelk_cbk_t func,
+                 void *data, const char *volume, fd_t *fd, int32_t cmd,
+                 struct gf_flock *flock, dict_t *xdata)
 {
     ec_cbk_t callback = { .finodelk = func };
     ec_fop_data_t * fop = NULL;
@@ -853,6 +856,7 @@ void ec_finodelk(call_frame_t * frame, xlator_t * this, uintptr_t target,
     fop->use_fd = 1;
 
     fop->int32 = cmd;
+    ec_owner_copy (fop->frame, owner);
 
     if (volume != NULL) {
         fop->str[0] = gf_strdup(volume);