fuse: handle mountflags properly

The internal mount API had no access to the generic
mountflags used by mount(2).

Thus the "ro" mount option that needs to be passed down to mount(2) as
as a mountflag was incorrectly mangled into the fuse-specific mount
parameter string (cf. http://review.gluster.com/655).

This commit fixes the internal API and the "ro" issue. It also adds a
check for the "rw" and "ro" mount options in tests/basic/mount.t.

Thanks to Csaba Henk (csaba@) for suggestions and proposing an updated
patch.

Change-Id: I7f7bf49ae44d148f5c16f10736a0e412fb8f5e67
BUG: 853895
Signed-off-by: Niels de Vos <ndevos@redhat.com>
Reviewed-on: http://review.gluster.org/4163
Reviewed-by: Csaba Henk <csaba@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>

4 files changed, 47 insertions, 14 deletions

diff --git a/contrib/fuse-include/fuse-mount.h b/contrib/fuse-include/fuse-mount.h
index 7a3756d92b8..9358ac810e1 100644
--- a/contrib/fuse-include/fuse-mount.h
+++ b/contrib/fuse-include/fuse-mount.h
@@ -8,5 +8,6 @@
 */
 
 void gf_fuse_unmount (const char *mountpoint, int fd);
-int gf_fuse_mount (const char *mountpoint, char *fsname, char *mnt_param,
+int gf_fuse_mount (const char *mountpoint, char *fsname,
+                   unsigned long mountflags, char *mnt_param,
                    pid_t *mtab_pid, int status_fd);
diff --git a/contrib/fuse-lib/mount.c b/contrib/fuse-lib/mount.c
index f02a835b3a8..fedde3fceea 100644
--- a/contrib/fuse-lib/mount.c
+++ b/contrib/fuse-lib/mount.c
@@ -100,7 +100,8 @@ escape (char *s)
 }
 
 static int
-fuse_mount_fusermount (const char *mountpoint, char *fsname, char *mnt_param,
+fuse_mount_fusermount (const char *mountpoint, char *fsname,
+                       unsigned long mountflags, char *mnt_param,
                        int fd)
 {
         int  pid = -1;
@@ -124,7 +125,8 @@ fuse_mount_fusermount (const char *mountpoint, char *fsname, char *mnt_param,
                 return -1;
         }
         ret = asprintf (&fm_mnt_params,
-                        "%s,fsname=%s,nonempty,subtype=glusterfs",
+                        "%s%s,fsname=%s,nonempty,subtype=glusterfs",
+                        (mountflags & MS_RDONLY) ? "ro," : "",
                         mnt_param, efsname);
         FREE (efsname);
         if (ret == -1) {
@@ -169,7 +171,8 @@ fuse_mount_fusermount (const char *mountpoint, char *fsname, char *mnt_param,
 }
 
 static int
-fuse_mount_sys (const char *mountpoint, char *fsname, char *mnt_param, int fd)
+fuse_mount_sys (const char *mountpoint, char *fsname,
+                unsigned long mountflags, char *mnt_param, int fd)
 {
         int ret = -1;
         unsigned mounted = 0;
@@ -185,7 +188,7 @@ fuse_mount_sys (const char *mountpoint, char *fsname, char *mnt_param, int fd)
 
                 goto out;
         }
-        ret = mount (source, mountpoint, fstype, 0,
+        ret = mount (source, mountpoint, fstype, mountflags,
                      mnt_param_mnt);
         if (ret == -1 && errno == ENODEV) {
                 /* fs subtype support was added by 79c0b2df aka
@@ -209,6 +212,7 @@ fuse_mount_sys (const char *mountpoint, char *fsname, char *mnt_param, int fd)
 #ifndef __NetBSD__
         if (geteuid () == 0) {
                 char *newmnt = fuse_mnt_resolve_path ("fuse", mountpoint);
+                char *mnt_param_mtab = NULL;
 
                 if (!newmnt) {
                         ret = -1;
@@ -216,8 +220,17 @@ fuse_mount_sys (const char *mountpoint, char *fsname, char *mnt_param, int fd)
                         goto out;
                 }
 
-                ret = fuse_mnt_add_mount ("fuse", source, newmnt, fstype,
-                                          mnt_param);
+                ret = asprintf (&mnt_param_mtab, "%s%s",
+                                mountflags & MS_RDONLY ? "ro," : "",
+                                mnt_param);
+                if (ret == -1)
+                        GFFUSE_LOGERR ("Out of memory");
+                else {
+                        ret = fuse_mnt_add_mount ("fuse", source, newmnt,
+                                                  fstype, mnt_param_mtab);
+                        FREE (mnt_param_mtab);
+                }
+
                 FREE (newmnt);
                 if (ret == -1) {
                         GFFUSE_LOGERR ("failed to add mtab entry");
@@ -240,7 +253,8 @@ out:
 }
 
 int
-gf_fuse_mount (const char *mountpoint, char *fsname, char *mnt_param,
+gf_fuse_mount (const char *mountpoint, char *fsname,
+               unsigned long mountflags, char *mnt_param,
                pid_t *mnt_pid, int status_fd)
 {
         int   fd  = -1;
@@ -268,14 +282,14 @@ gf_fuse_mount (const char *mountpoint, char *fsname, char *mnt_param,
                                 exit (pid == -1 ? 1 : 0);
                 }
 
-                ret = fuse_mount_sys (mountpoint, fsname, mnt_param, fd);
+                ret = fuse_mount_sys (mountpoint, fsname, mountflags, mnt_param, fd);
                 if (ret == -1) {
                         gf_log ("glusterfs-fuse", GF_LOG_INFO,
                                 "direct mount failed (%s), "
                                 "retry to mount via fusermount",
                                 strerror (errno));
 
-                        ret = fuse_mount_fusermount (mountpoint, fsname,
+                        ret = fuse_mount_fusermount (mountpoint, fsname, mountflags,
                                                      mnt_param, fd);
                 }
 
diff --git a/tests/basic/mount.t b/tests/basic/mount.t
index 0fdef65de55..7b2769643a8 100755
--- a/tests/basic/mount.t
+++ b/tests/basic/mount.t
@@ -34,9 +34,20 @@ EXPECT 'Started' volinfo_field $V0 'Status';
 ## Make volume tightly consistent for metdata
 TEST $CLI volume set $V0 performance.stat-prefetch off;
 
-## Mount FUSE with caching disabled
+## Mount FUSE with caching disabled (read-write)
 TEST glusterfs --entry-timeout=0 --attribute-timeout=0 -s $H0 --volfile-id $V0 $M0;
 
+## Check consistent "rw" option
+TEST 'mount -t fuse.glusterfs | grep -E "^$H0:$V0 .+ \(rw,"';
+TEST 'grep -E "^$H0:$V0 .+ ,?rw," /proc/mounts';
+
+## Mount FUSE with caching disabled (read-only)
+TEST glusterfs --entry-timeout=0 --attribute-timeout=0 --read-only -s $H0 --volfile-id $V0 $M1;
+
+## Check consistent "ro" option
+TEST 'mount -t fuse.glusterfs | grep -E "^$H0:$V0 .+ \(ro,"';
+TEST 'grep -E "^$H0:$V0 .+ ,?ro,.+" /proc/mounts';
+
 ## Wait for volume to register with rpc.mountd
 sleep 5;
 
@@ -45,11 +56,16 @@ TEST mount -t nfs -o vers=3,nolock,soft,intr $H0:/$V0 $N0;
 
 
 ## Test for consistent views between NFS and FUSE mounts
+## write access to $M1 should fail
 TEST ! stat $M0/newfile;
+TEST ! touch $M1/newfile;
 TEST touch $M0/newfile;
+TEST stat $M1/newfile;
 TEST stat $N0/newfile;
+TEST ! rm $M1/newfile;
 TEST rm $N0/newfile;
 TEST ! stat $M0/newfile;
+TEST ! stat $M1/newfile;
 
 
 ## Finish up
diff --git a/xlators/mount/fuse/src/fuse-bridge.c b/xlators/mount/fuse/src/fuse-bridge.c
index 9be7d91cc45..544dec0c3b5 100644
--- a/xlators/mount/fuse/src/fuse-bridge.c
+++ b/xlators/mount/fuse/src/fuse-bridge.c
@@ -4678,6 +4678,7 @@ init (xlator_t *this_xl)
         int                fsname_allocated = 0;
         glusterfs_ctx_t   *ctx = NULL;
         gf_boolean_t       sync_to_mount = _gf_false;
+        unsigned long      mntflags = 0;
         char              *mnt_args = NULL;
         eh_t              *event = NULL;
 
@@ -4889,8 +4890,9 @@ init (xlator_t *this_xl)
                 goto cleanup_exit;
         }
 
-        gf_asprintf (&mnt_args, "%s%s%s%sallow_other,max_read=131072",
-                     priv->read_only ? "ro," : "",
+        if (priv->read_only)
+                mntflags |= MS_RDONLY;
+        gf_asprintf (&mnt_args, "%s%s%sallow_other,max_read=131072",
                      priv->acl ? "" : "default_permissions,",
                      priv->fuse_mountopts ? priv->fuse_mountopts : "",
                      priv->fuse_mountopts ? "," : "");
@@ -4903,7 +4905,7 @@ init (xlator_t *this_xl)
                 goto cleanup_exit;
         }
 
-        priv->fd = gf_fuse_mount (priv->mount_point, fsname, mnt_args,
+        priv->fd = gf_fuse_mount (priv->mount_point, fsname, mntflags, mnt_args,
                                   sync_to_mount ? &ctx->mnt_pid : NULL,
                                   priv->status_pipe[1]);
         if (priv->fd == -1)