dht/md-cache: Filter invalidate if the file is made a linkto file

Upcall as a part of setattr, sends an invalidation and the
invalidation carries the resulting stat value. When a file
is converted to linkto files, even then an invalidation
is set and as a result the mountpoint shows the sticky
bit in the stat of the file.
eg: ---------T. 945 root root 0 Nov  8 10:14 hardlink.999

Fix:
When dht recieves a notification of sticky bit change, it updates
the flag, to indicate md-cache to send the subsequent lookup.

Change-Id: Ic2fd7a5b196db0754f9b97072e644e6bf69da606
BUG: 1392713
Signed-off-by: Poornima G <pgurusid@redhat.com>
Reviewed-on: http://review.gluster.org/15789
Smoke: Gluster Build System <jenkins@build.gluster.org>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
Reviewed-by: Niels de Vos <ndevos@redhat.com>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Susant Palai <spalai@redhat.com>
Reviewed-by: Rajesh Joseph <rjoseph@redhat.com>

1 files changed, 51 insertions, 0 deletions

diff --git a/xlators/performance/md-cache/src/md-cache.c b/xlators/performance/md-cache/src/md-cache.c
index aa1c22ade51..9edbdf4aebe 100644
--- a/xlators/performance/md-cache/src/md-cache.c
+++ b/xlators/performance/md-cache/src/md-cache.c
@@ -40,6 +40,8 @@ struct mdc_statistics {
                                      sent to bricks */
         uint64_t stat_invals; /* No. of invalidates recieved from upcall*/
         uint64_t xattr_invals; /* No. of invalidates recieved from upcall*/
+        uint64_t need_lookup; /* No. of lookups issued, because other xlators
+                               * requested for explicit lookup */
         gf_lock_t lock;
 };
 
@@ -153,6 +155,7 @@ struct md_cache {
         char         *linkname;
 	time_t        ia_time;
 	time_t        xa_time;
+        gf_boolean_t  need_lookup;
         gf_lock_t     lock;
 };
 
@@ -791,6 +794,43 @@ out:
         return ret;
 }
 
+gf_boolean_t
+mdc_inode_reset_need_lookup (xlator_t *this, inode_t *inode)
+{
+        struct md_cache *mdc  = NULL;
+        gf_boolean_t     need = _gf_false;
+
+        if (mdc_inode_ctx_get (this, inode, &mdc) != 0)
+                goto out;
+
+        LOCK (&mdc->lock);
+        {
+                need = mdc->need_lookup;
+                mdc->need_lookup = _gf_false;
+        }
+        UNLOCK (&mdc->lock);
+
+out:
+        return need;
+}
+
+void
+mdc_inode_set_need_lookup (xlator_t *this, inode_t *inode, gf_boolean_t need)
+{
+        struct md_cache *mdc = NULL;
+
+        if (mdc_inode_ctx_get (this, inode, &mdc) != 0)
+                goto out;
+
+        LOCK (&mdc->lock);
+        {
+                mdc->need_lookup = need;
+        }
+        UNLOCK (&mdc->lock);
+
+out:
+        return;
+}
 
 void
 mdc_inode_iatt_invalidate (xlator_t *this, inode_t *inode)
@@ -1034,6 +1074,12 @@ mdc_lookup (call_frame_t *frame, xlator_t *this, loc_t *loc,
 		goto uncached;
         }
 
+        if (mdc_inode_reset_need_lookup (this, loc->inode)) {
+                INCREMENT_ATOMIC (conf->mdc_counter.lock,
+                                  conf->mdc_counter.need_lookup);
+                goto uncached;
+        }
+
         ret = mdc_inode_iatt_get (this, loc->inode, &stbuf);
         if (ret != 0) {
                 INCREMENT_ATOMIC (conf->mdc_counter.lock,
@@ -2593,6 +2639,11 @@ mdc_invalidate (xlator_t *this, void *data)
                                 mdc_update_gfid_stat (this, &up_ci->oldp_stat);
         }
 
+        if (up_ci->flags & UP_EXPLICIT_LOOKUP) {
+                mdc_inode_set_need_lookup (this, inode, _gf_true);
+                goto out;
+        }
+
         if ((up_ci->flags & (UP_NLINK | UP_RENAME_FLAGS | UP_FORGET)) ||
             (up_ci->dict && dict_get (up_ci->dict, MDC_INVALIDATE_IATT))) {
                 mdc_inode_iatt_invalidate (this, inode);