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>

BUG: 1412922
Change-Id: I18c553adaa0cbc8df55876accc1e1dcd4ee9c116
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Reviewed-on: http://review.gluster.org/16394
Smoke: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Xavier Hernandez <xhernandez@datalab.es>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>

6 files changed, 42 insertions, 34 deletions

diff --git a/xlators/cluster/ec/src/ec-common.c b/xlators/cluster/ec/src/ec-common.c
index e65b1a1ae18..2b4cec406a9 100644
--- a/xlators/cluster/ec/src/ec-common.c
+++ b/xlators/cluster/ec/src/ec-common.c
@@ -1443,20 +1443,21 @@ gf_boolean_t ec_lock_acquire(ec_lock_link_t *link)
 {
     ec_lock_t *lock;
     ec_fop_data_t *fop;
+    gf_lkowner_t lk_owner;
 
     lock = link->lock;
     fop = link->fop;
 
     if (!lock->acquired) {
-        ec_owner_set(fop->frame, lock);
+        set_lk_owner_from_ptr(&lk_owner, lock);
 
         ec_trace("LOCK_ACQUIRE", fop, "lock=%p, inode=%p", lock,
                  lock->loc.inode);
 
         lock->flock.l_type = F_WRLCK;
-        ec_inodelk(fop->frame, fop->xl, -1, EC_MINIMUM_ALL, ec_locked,
-                   link, fop->xl->name, &lock->loc, F_SETLKW, &lock->flock,
-                   NULL);
+        ec_inodelk(fop->frame, fop->xl, &lk_owner, -1, EC_MINIMUM_ALL,
+                   ec_locked, link, fop->xl->name, &lock->loc, F_SETLKW,
+                   &lock->flock, NULL);
 
         return _gf_false;
     }
@@ -1761,6 +1762,7 @@ void ec_unlock_lock(ec_lock_link_t *link)
 {
     ec_lock_t *lock;
     ec_fop_data_t *fop;
+    gf_lkowner_t lk_owner;
 
     lock = link->lock;
     fop = link->fop;
@@ -1768,13 +1770,13 @@ void ec_unlock_lock(ec_lock_link_t *link)
     ec_clear_inode_info(fop, lock->loc.inode);
 
     if ((lock->mask != 0) && lock->acquired) {
-        ec_owner_set(fop->frame, lock);
+        set_lk_owner_from_ptr(&lk_owner, lock);
 
         lock->flock.l_type = F_UNLCK;
         ec_trace("UNLOCK_INODELK", fop, "lock=%p, inode=%p", lock,
                  lock->loc.inode);
 
-        ec_inodelk(fop->frame, fop->xl, lock->mask, EC_MINIMUM_ONE,
+        ec_inodelk(fop->frame, fop->xl, &lk_owner, lock->mask, EC_MINIMUM_ONE,
                    ec_unlocked, link, fop->xl->name, &lock->loc, F_SETLK,
                    &lock->flock, NULL);
     } else {
diff --git a/xlators/cluster/ec/src/ec-fops.h b/xlators/cluster/ec/src/ec-fops.h
index 8d938427a18..bbacedc0140 100644
--- a/xlators/cluster/ec/src/ec-fops.h
+++ b/xlators/cluster/ec/src/ec-fops.h
@@ -63,16 +63,16 @@ void ec_fheal(call_frame_t * frame, xlator_t * this, uintptr_t target,
               int32_t minimum, fop_fheal_cbk_t func, void *data, fd_t * fd,
               int32_t partial, dict_t *xdata);
 
-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_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,
+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);
 
+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);
+
 void ec_link(call_frame_t * frame, xlator_t * this, uintptr_t target,
              int32_t minimum, fop_link_cbk_t func, void *data, loc_t * oldloc,
              loc_t * newloc, dict_t * xdata);
diff --git a/xlators/cluster/ec/src/ec-heal.c b/xlators/cluster/ec/src/ec-heal.c
index 051d218331a..da08f6c9a75 100644
--- a/xlators/cluster/ec/src/ec-heal.c
+++ b/xlators/cluster/ec/src/ec-heal.c
@@ -177,14 +177,17 @@ void ec_heal_lock(ec_heal_t *heal, int32_t type, fd_t *fd, loc_t *loc,
 
     if (fd != NULL)
     {
-        ec_finodelk(heal->fop->frame, heal->xl, heal->fop->mask,
+        ec_finodelk(heal->fop->frame, heal->xl,
+                    &heal->fop->frame->root->lk_owner, heal->fop->mask,
                     EC_MINIMUM_ALL, cbk, heal, heal->xl->name, fd, F_SETLKW,
                     &flock, NULL);
     }
     else
     {
-        ec_inodelk(heal->fop->frame, heal->xl, heal->fop->mask, EC_MINIMUM_ALL,
-                   cbk, heal, heal->xl->name, loc, F_SETLKW, &flock, NULL);
+        ec_inodelk(heal->fop->frame, heal->xl,
+                   &heal->fop->frame->root->lk_owner, heal->fop->mask,
+                   EC_MINIMUM_ALL, cbk, heal, heal->xl->name, loc, F_SETLKW,
+                   &flock, NULL);
     }
 }
 
diff --git a/xlators/cluster/ec/src/ec-helpers.c b/xlators/cluster/ec/src/ec-helpers.c
index 7cf8232353d..7df83126ae5 100644
--- a/xlators/cluster/ec/src/ec-helpers.c
+++ b/xlators/cluster/ec/src/ec-helpers.c
@@ -643,10 +643,9 @@ void ec_owner_set(call_frame_t * frame, void * owner)
     set_lk_owner_from_ptr(&frame->root->lk_owner, owner);
 }
 
-void ec_owner_copy(call_frame_t * frame, gf_lkowner_t * owner)
+void ec_owner_copy(call_frame_t *frame, gf_lkowner_t *owner)
 {
-    frame->root->lk_owner.len = owner->len;
-    memcpy(frame->root->lk_owner.data, owner->data, owner->len);
+    lk_owner_copy (&frame->root->lk_owner, owner);
 }
 
 ec_inode_t * __ec_inode_get(inode_t * inode, xlator_t * xl)
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);
diff --git a/xlators/cluster/ec/src/ec.c b/xlators/cluster/ec/src/ec.c
index 94d1241b364..b5e6bc08216 100644
--- a/xlators/cluster/ec/src/ec.c
+++ b/xlators/cluster/ec/src/ec.c
@@ -839,8 +839,8 @@ int32_t ec_gf_inodelk(call_frame_t * frame, xlator_t * this,
     if (flock->l_type == F_UNLCK)
             minimum = EC_MINIMUM_ONE;
 
-    ec_inodelk(frame, this, -1, minimum, default_inodelk_cbk, NULL,
-               volume, loc, cmd, flock, xdata);
+    ec_inodelk(frame, this, &frame->root->lk_owner, -1, minimum,
+               default_inodelk_cbk, NULL, volume, loc, cmd, flock, xdata);
 
     return 0;
 }
@@ -852,8 +852,8 @@ int32_t ec_gf_finodelk(call_frame_t * frame, xlator_t * this,
     int32_t minimum = EC_MINIMUM_ALL;
     if (flock->l_type == F_UNLCK)
             minimum = EC_MINIMUM_ONE;
-    ec_finodelk(frame, this, -1, minimum, default_finodelk_cbk, NULL,
-                volume, fd, cmd, flock, xdata);
+    ec_finodelk(frame, this, &frame->root->lk_owner, -1, minimum,
+                default_finodelk_cbk, NULL, volume, fd, cmd, flock, xdata);
 
     return 0;
 }