nfs3: Force root lookup before starting fh resolution

Signed-off-by: Shehjar Tikoo <shehjart@gluster.com>
Signed-off-by: Anand V. Avati <avati@dev.gluster.com>

BUG: 2200 (cp dies with "Invalid argument" after failover)
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=2200

3 files changed, 127 insertions, 7 deletions

diff --git a/xlators/nfs/server/src/nfs3-helpers.c b/xlators/nfs/server/src/nfs3-helpers.c
index a74a90412..05baee3aa 100644
--- a/xlators/nfs/server/src/nfs3-helpers.c
+++ b/xlators/nfs/server/src/nfs3-helpers.c
@@ -37,6 +37,13 @@
 #include "iatt.h"
 #include <string.h>
 
+extern int
+nfs3_set_root_looked_up (struct nfs3_state *nfs3, struct nfs3_fh *rootfh);
+
+extern int
+nfs3_is_root_looked_up (struct nfs3_state *nfs3, struct nfs3_fh *rootfh);
+
+
 #define nfs3_call_resume(cst)                                   \
         do {                                                    \
                 if (((cst)) && (cst)->resume_fn)                \
@@ -3116,6 +3123,85 @@ nfs3_fh_resolve_entry (nfs3_call_state_t *cs)
         return 0;
 }
 
+
+int
+nfs3_fh_resolve_resume (nfs3_call_state_t *cs)
+{
+        int     ret = -EFAULT;
+
+        if (!cs)
+                return ret;
+
+        if (cs->resolve_ret < 0)
+                goto err_resume_call;
+
+        if (!cs->resolventry)
+                ret = nfs3_fh_resolve_inode (cs);
+        else
+                ret = nfs3_fh_resolve_entry (cs);
+
+err_resume_call:
+        if (ret < 0)
+                nfs3_call_resume (cs);
+
+        return ret;
+}
+
+
+int32_t
+nfs3_fh_resolve_root_lookup_cbk (call_frame_t *frame, void *cookie,
+                                 xlator_t *this, int32_t op_ret,
+                                 int32_t op_errno, inode_t *inode,
+                                 struct iatt *buf, dict_t *xattr,
+                                 struct iatt *postparent)
+{
+        nfs3_call_state_t       *cs = NULL;
+
+        cs = frame->local;
+        cs->resolve_ret = op_ret;
+        cs->resolve_errno = op_errno;
+
+        if (op_ret == -1) {
+                gf_log (GF_NFS3, GF_LOG_TRACE, "Lookup failed: %s: %s",
+                        cs->resolvedloc.path, strerror (op_errno));
+                goto err;
+        } else
+                gf_log (GF_NFS3, GF_LOG_TRACE, "Entry looked up: %s",
+                        cs->resolvedloc.path);
+
+        nfs3_set_root_looked_up (cs->nfs3state, &cs->resolvefh);
+err:
+        nfs3_fh_resolve_resume (cs);
+        return 0;
+}
+
+
+int
+nfs3_fh_resolve_root (nfs3_call_state_t *cs)
+{
+        int             ret = -EFAULT;
+        nfs_user_t      nfu = {0, };
+
+        if (!cs)
+                return ret;
+
+        if (nfs3_is_root_looked_up (cs->nfs3state, &cs->resolvefh)) {
+                ret = nfs3_fh_resolve_resume (cs);
+                goto out;
+        }
+
+        nfs_user_root_create (&nfu);
+        gf_log (GF_NFS3, GF_LOG_TRACE, "Root needs lookup");
+        ret = nfs_root_loc_fill (cs->vol->itable, &cs->resolvedloc);
+
+        ret = nfs_lookup (cs->nfsx, cs->vol, &nfu, &cs->resolvedloc,
+                          nfs3_fh_resolve_root_lookup_cbk, cs);
+
+out:
+        return ret;
+}
+
+
 int
 nfs3_fh_resolve_and_resume (nfs3_call_state_t *cs, struct nfs3_fh *fh,
                             char *entry, nfs3_resume_fn_t resum_fn)
@@ -3136,18 +3222,13 @@ nfs3_fh_resolve_and_resume (nfs3_call_state_t *cs, struct nfs3_fh *fh,
          *
          * b. (fh, basename) resolution
          */
-        if (!entry)     /* a */
-                ret = nfs3_fh_resolve_inode (cs);
-        else {          /* b */
+        if (entry) {    /* b */
                 cs->resolventry = gf_strdup (entry);
                 if (!cs->resolventry)
                         goto err;
-
-                ret = nfs3_fh_resolve_entry (cs);
         }
 
+        ret = nfs3_fh_resolve_root (cs);
 err:
         return ret;
 }
-
-
diff --git a/xlators/nfs/server/src/nfs3.c b/xlators/nfs/server/src/nfs3.c
index 46f7f7c5c..de32a2de0 100644
--- a/xlators/nfs/server/src/nfs3.c
+++ b/xlators/nfs/server/src/nfs3.c
@@ -174,6 +174,44 @@ out:
 }
 
 
+int
+nfs3_is_root_looked_up (struct nfs3_state *nfs3, struct nfs3_fh *rootfh)
+{
+        struct nfs3_export      *exp = NULL;
+        int                     ret = 0;
+
+        if ((!nfs3) || (!rootfh))
+                return 0;
+
+        exp = __nfs3_get_export_by_exportid (nfs3, rootfh->exportid);
+        if (!exp)
+                goto out;
+
+        ret = exp->rootlookedup;
+out:
+        return ret;
+}
+
+
+int
+nfs3_set_root_looked_up (struct nfs3_state *nfs3, struct nfs3_fh *rootfh)
+{
+        struct nfs3_export      *exp = NULL;
+        int                     ret = 0;
+
+        if ((!nfs3) || (!rootfh))
+                return 0;
+
+        exp = __nfs3_get_export_by_exportid (nfs3, rootfh->exportid);
+        if (!exp)
+                goto out;
+
+        exp->rootlookedup = 1;
+out:
+        return ret;
+}
+
+
 #define nfs3_map_fh_to_volume(nfs3state, handle, rqst, volume, status, label) \
         do {                                                            \
                 volume = nfs3_fh_to_xlator ((nfs3state), handle);       \
diff --git a/xlators/nfs/server/src/nfs3.h b/xlators/nfs/server/src/nfs3.h
index 7301fe0d8..bf4371a8a 100644
--- a/xlators/nfs/server/src/nfs3.h
+++ b/xlators/nfs/server/src/nfs3.h
@@ -88,6 +88,7 @@ struct nfs3_export {
         int                     access;
         int                     trusted_sync;
         int                     trusted_write;
+        int                     rootlookedup;
 };
 
 #define GF_NFS3_DEFAULT_VOLACCESS       (GF_NFS3_VOLACCESS_RW)