Do not hardcode umount(8) path, emulate lazy umount

1) Use a system-dependent macro for umount(8) location instead of
relying on $PATH  to find it, for security and portability sake.

2) Introduce gf_umount_lazy() to replace umount -l (-l for lazy) invocations,
which is only supported on Linux; On Linux behavior in unchanged. On other
systems, we fork an external process (umountd) that will take care of
periodically attempt to unmount, and optionally rmdir.

Backport of Ia91167c0652f8ddab85136324b08f87c5ac1edd51d

BUG: 1138897
Change-Id: I9d82c87e85af0dee79f2de39bc697c486b7103c8
Signed-off-by: Emmanuel Dreyfus <manu@netbsd.org>
Reviewed-on: http://review.gluster.org/8863
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Csaba Henk <csaba@redhat.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

1 files changed, 2 insertions, 12 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-utils.c b/xlators/mgmt/glusterd/src/glusterd-utils.c
index bee17e50c51..0696725c717 100644
--- a/xlators/mgmt/glusterd/src/glusterd-utils.c
+++ b/xlators/mgmt/glusterd/src/glusterd-utils.c
@@ -11972,7 +11972,6 @@ int
 glusterd_remove_auxiliary_mount (char *volname)
 {
         int       ret                = -1;
-        runner_t  runner             = {0,};
         char      mountdir[PATH_MAX] = {0,};
         char      pidfile[PATH_MAX]  = {0,};
         xlator_t *this               = NULL;
@@ -11989,20 +11988,11 @@ glusterd_remove_auxiliary_mount (char *volname)
         }
 
         GLUSTERD_GET_QUOTA_AUX_MOUNT_PATH (mountdir, volname, "/");
-        runinit (&runner);
-        runner_add_args (&runner, "umount",
-
-#if GF_LINUX_HOST_OS
-                        "-l",
-#endif
-                        mountdir, NULL);
-        ret = runner_run_reuse (&runner);
+        ret = gf_umount_lazy (this->name, mountdir, 1);
         if (ret)
                 gf_log (this->name, GF_LOG_ERROR, "umount on %s failed, "
                         "reason : %s", mountdir, strerror (errno));
-        runner_end (&runner);
 
-        rmdir (mountdir);
         return ret;
 }
 
@@ -12127,7 +12117,7 @@ glusterd_umount (const char *path)
 
         runinit (&runner);
         snprintf (msg, sizeof (msg), "umount path %s", path);
-        runner_add_args (&runner, "umount", "-f", path, NULL);
+        runner_add_args (&runner, _PATH_UMOUNT, "-f", path, NULL);
         runner_log (&runner, this->name, GF_LOG_DEBUG, msg);
         ret = runner_run (&runner);
         if (ret)