rpc.nfsd: mount up nfsdfs is it doesn't appear to be mounted yet

[nfs-utils.git] / utils / nfsd / nfssvc.c

diff --git a/utils/nfsd/nfssvc.c b/utils/nfsd/nfssvc.c
index 34c67ca11b927ff6201e2d6b61a2e9c8c605ae7b..7693626fc1a579110b3b163c71663a1bd11b8fcc 100644 (file)
--- a/utils/nfsd/nfssvc.c
+++ b/utils/nfsd/nfssvc.c
@@ -15,9 +15,11 @@
 #include <netdb.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
+#include <sys/stat.h>
 #include <unistd.h>
 #include <fcntl.h>
 #include <errno.h>
+#include <stdlib.h>
 
 #include "nfslib.h"
 #include "xlog.h"
@@ -31,9 +33,13 @@
  */
 #undef IPV6_SUPPORTED
 
-#define NFSD_PORTS_FILE     "/proc/fs/nfsd/portlist"
-#define NFSD_VERS_FILE    "/proc/fs/nfsd/versions"
-#define NFSD_THREAD_FILE  "/proc/fs/nfsd/threads"
+#ifndef NFSD_FS_DIR
+#define NFSD_FS_DIR      "/proc/fs/nfsd"
+#endif
+
+#define NFSD_PORTS_FILE   NFSD_FS_DIR "/portlist"
+#define NFSD_VERS_FILE    NFSD_FS_DIR "/versions"
+#define NFSD_THREAD_FILE  NFSD_FS_DIR "/threads"
 
 /*
  * declaring a common static scratch buffer here keeps us from having to
@@ -43,6 +49,46 @@
  */
 char buf[128];
 
+/*
+ * Using the "new" interfaces for nfsd requires that /proc/fs/nfsd is
+ * actually mounted. Make an attempt to mount it here if it doesn't appear
+ * to be. If the mount attempt fails, no big deal -- fall back to using nfsctl
+ * instead.
+ */
+void
+nfssvc_mount_nfsdfs(char *progname)
+{
+       int err;
+       struct stat statbuf;
+
+       err = stat(NFSD_THREAD_FILE, &statbuf);
+       if (err == 0)
+               return;
+
+       if (errno != ENOENT) {
+               xlog(L_ERROR, "Unable to stat %s: errno %d (%m)",
+                               NFSD_THREAD_FILE, errno);
+               return;
+       }
+
+       /*
+        * this call can return an error if modprobe is set up to automatically
+        * mount nfsdfs when nfsd.ko is plugged in. So, ignore the return
+        * code from it and just check for the "threads" file afterward.
+        */
+       system("/bin/mount -t nfsd nfsd " NFSD_FS_DIR " >/dev/null 2>&1");
+
+       err = stat(NFSD_THREAD_FILE, &statbuf);
+       if (err == 0)
+               return;
+
+       xlog(L_WARNING, "Unable to access " NFSD_FS_DIR " errno %d (%m)." 
+               "\nPlease try, as root, 'mount -t nfsd nfsd " NFSD_FS_DIR 
+               "' and then restart %s to correct the problem", errno, progname);
+
+       return;
+}
+
 /*
  * Are there already sockets configured? If not, then it is safe to try to
  * open some and pass them through.