nfs: revalidate lookup converted to fresh lookup

Backport of http://review.gluster.org/15580

when an inode ctx is missing for a linked inode the revalidate
lookups are converted to fresh.

This could result in sending ESTALE when the gfid are recreated

We are not able to reproduce the issue with normal setup, most part of
RCA was done with code reading.

Possible scenario in which  this bug can reproduce,
Delete a file and recreate a new file with same name, at the same time
from another client process try to list/or access the file.

In this case the second client may throw an ESTALE error for such files

Thanks to Soumya and Pranith for doing the complete RCA

>Change-Id: I73992a65844b09a169cefaaedc0dcfb129d66ea1
>BUG: 1379720
>Signed-off-by: Mohammed Rafi KC <rkavunga@redhat.com>
>Reviewed-on: http://review.gluster.org/15580
>NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
>CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
>Smoke: Gluster Build System <jenkins@build.gluster.org>
>Reviewed-by: soumya k <skoduri@redhat.com>
>Reviewed-by: Kaleb KEITHLEY <kkeithle@redhat.com>

Change-Id: Ifd0d92e29e409e5b23790b677034cfc8f3184d1a
BUG: 1394635
Signed-off-by: Mohammed Rafi KC <rkavunga@redhat.com>
Reviewed-on: http://review.gluster.org/15840
Smoke: Gluster Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Niels de Vos <ndevos@redhat.com>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>

4 files changed, 15 insertions, 10 deletions

diff --git a/xlators/nfs/server/src/mount3.c b/xlators/nfs/server/src/mount3.c
index 2647e384a94..48b719d29aa 100644
--- a/xlators/nfs/server/src/mount3.c
+++ b/xlators/nfs/server/src/mount3.c
@@ -1059,7 +1059,7 @@ __mnt3_resolve_export_subdir_comp (mnt3_resolve_t *mres)
         nfs_loc_wipe (&mres->resolveloc);
         ret = nfs_entry_loc_fill (mres->mstate->nfsx, mres->exp->vol->itable,
                                   gfid, nextcomp, &mres->resolveloc,
-                                  NFS_RESOLVE_CREATE);
+                                  NFS_RESOLVE_CREATE, NULL);
         if ((ret < 0) && (ret != -2)) {
                 gf_msg (GF_MNT, GF_LOG_ERROR, EFAULT,
                         NFS_MSG_RESOLVE_INODE_FAIL, "Failed to resolve and "
@@ -1374,7 +1374,7 @@ __mnt3_resolve_subdir (mnt3_resolve_t *mres)
         rootgfid[15] = 1;
         ret = nfs_entry_loc_fill (mres->mstate->nfsx, mres->exp->vol->itable,
                                   rootgfid, firstcomp, &mres->resolveloc,
-                                  NFS_RESOLVE_CREATE);
+                                  NFS_RESOLVE_CREATE, NULL);
         if ((ret < 0) && (ret != -2)) {
                 gf_msg (GF_MNT, GF_LOG_ERROR, EFAULT,
                         NFS_MSG_RESOLVE_INODE_FAIL, "Failed to resolve and "
diff --git a/xlators/nfs/server/src/nfs-common.c b/xlators/nfs/server/src/nfs-common.c
index d9ea1e1ac47..af37f6b264c 100644
--- a/xlators/nfs/server/src/nfs-common.c
+++ b/xlators/nfs/server/src/nfs-common.c
@@ -308,7 +308,7 @@ err:
  */
 int
 nfs_entry_loc_fill (xlator_t *this, inode_table_t *itable, uuid_t pargfid,
-                    char *entry, loc_t *loc, int how)
+                    char *entry, loc_t *loc, int how, gf_boolean_t *freshlookup)
 {
         inode_t         *parent = NULL;
         inode_t         *entryinode = NULL;
@@ -337,8 +337,11 @@ nfs_entry_loc_fill (xlator_t *this, inode_table_t *itable, uuid_t pargfid,
                          * that the caller can use the filled loc to call
                          * lookup.
                          */
-                        if (!entryinode)
+                        if (!entryinode) {
                                 entryinode = inode_new (itable);
+                                if (freshlookup)
+                                        *freshlookup = _gf_true;
+                        }
                         /* Cannot change ret because that must
                          * continue to have -2.
                          */
diff --git a/xlators/nfs/server/src/nfs-common.h b/xlators/nfs/server/src/nfs-common.h
index 77bdfb0bbf0..8c9a1e33457 100644
--- a/xlators/nfs/server/src/nfs-common.h
+++ b/xlators/nfs/server/src/nfs-common.h
@@ -57,7 +57,8 @@ nfs_ino_loc_fill (inode_table_t *itable, uuid_t gfid, loc_t *l);
 
 extern int
 nfs_entry_loc_fill (xlator_t *this, inode_table_t *itable, uuid_t pargfid,
-                    char *entry, loc_t *loc, int how);
+                    char *entry, loc_t *loc, int how,
+                    gf_boolean_t *freshlookup);
 
 extern int
 nfs_root_loc_fill (inode_table_t *itable, loc_t *loc);
diff --git a/xlators/nfs/server/src/nfs3-helpers.c b/xlators/nfs/server/src/nfs3-helpers.c
index 5ed57bde0e2..0b977092fbb 100644
--- a/xlators/nfs/server/src/nfs3-helpers.c
+++ b/xlators/nfs/server/src/nfs3-helpers.c
@@ -3757,8 +3757,9 @@ out:
 int
 nfs3_fh_resolve_entry_hard (nfs3_call_state_t *cs)
 {
-        int             ret = -EFAULT;
-        nfs_user_t      nfu = {0, };
+        int                     ret             = -EFAULT;
+        nfs_user_t              nfu             = {0, };
+        gf_boolean_t            freshlookup     = _gf_false;
 
         if (!cs)
                 return ret;
@@ -3771,7 +3772,7 @@ nfs3_fh_resolve_entry_hard (nfs3_call_state_t *cs)
 
         ret = nfs_entry_loc_fill (cs->nfsx, cs->vol->itable, cs->resolvefh.gfid,
                                   cs->resolventry, &cs->resolvedloc,
-                                  NFS_RESOLVE_CREATE);
+                                  NFS_RESOLVE_CREATE, &freshlookup);
 
         if (ret == -2) {
                 gf_msg_trace (GF_NFS3, 0, "Entry needs lookup: %s",
@@ -3782,8 +3783,8 @@ nfs3_fh_resolve_entry_hard (nfs3_call_state_t *cs)
 		 * go ahead in the resume callback so that an EEXIST gets
 		 * handled at posix without an extra fop at this point.
 		 */
-                if (nfs3_lookup_op (cs) ||
-		    (nfs3_create_op (cs) && !nfs3_create_exclusive_op (cs))) {
+                if (freshlookup && (nfs3_lookup_op (cs) ||
+		    (nfs3_create_op (cs) && !nfs3_create_exclusive_op (cs)))) {
                         cs->lookuptype = GF_NFS3_FRESH;
                         cs->resolve_ret = 0;
                         cs->hardresolved = 0;