3 files changed, 74 insertions, 17 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 5c97d47676ae..bf11d6879ab4 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -3249,12 +3249,14 @@ nfs4_state_shutdown(void)
         nfs4_unlock_state();
 }
 
+/*
+ * user_recovery_dirname is protected by the nfsd_mutex since it's only
+ * accessed when nfsd is starting.
+ */
 static void
 nfs4_set_recdir(char *recdir)
 {
-        nfs4_lock_state();
         strcpy(user_recovery_dirname, recdir);
-        nfs4_unlock_state();
 }
 
 /*
@@ -3278,6 +3280,12 @@ nfs4_reset_recoverydir(char *recdir)
         return status;
 }
 
+char *
+nfs4_recoverydir(void)
+{
+        return user_recovery_dirname;
+}
+
 /*
  * Called when leasetime is changed.
  *
@@ -3286,11 +3294,12 @@ nfs4_reset_recoverydir(char *recdir)
  * we start to register any changes in lease time.  If the administrator
  * really wants to change the lease time *now*, they can go ahead and bring
  * nfsd down and then back up again after changing the lease time.
+ *
+ * user_lease_time is protected by nfsd_mutex since it's only really accessed
+ * when nfsd is starting
  */
 void
 nfs4_reset_lease(time_t leasetime)
 {
-        lock_kernel();
         user_lease_time = leasetime;
-        unlock_kernel();
 }
diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 049d2a9c7715..2c2eb8796c10 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -509,7 +509,7 @@ out_free:
         return rv;
 }
 
-static ssize_t write_versions(struct file *file, char *buf, size_t size)
+static ssize_t __write_versions(struct file *file, char *buf, size_t size)
 {
         /*
          * Format:
@@ -572,6 +572,16 @@ static ssize_t write_versions(struct file *file, char *buf, size_t size)
         return len;
 }
 
+static ssize_t write_versions(struct file *file, char *buf, size_t size)
+{
+        ssize_t rv;
+
+        mutex_lock(&nfsd_mutex);
+        rv = __write_versions(file, buf, size);
+        mutex_unlock(&nfsd_mutex);
+        return rv;
+}
+
 static ssize_t __write_ports(struct file *file, char *buf, size_t size)
 {
         if (size == 0) {
@@ -675,6 +685,7 @@ static ssize_t __write_ports(struct file *file, char *buf, size_t size)
 static ssize_t write_ports(struct file *file, char *buf, size_t size)
 {
         ssize_t rv;
+
         mutex_lock(&nfsd_mutex);
         rv = __write_ports(file, buf, size);
         mutex_unlock(&nfsd_mutex);
@@ -714,16 +725,17 @@ static ssize_t write_maxblksize(struct file *file, char *buf, size_t size)
 #ifdef CONFIG_NFSD_V4
 extern time_t nfs4_leasetime(void);
 
-static ssize_t write_leasetime(struct file *file, char *buf, size_t size)
+static ssize_t __write_leasetime(struct file *file, char *buf, size_t size)
 {
         /* if size > 10 seconds, call
          * nfs4_reset_lease() then write out the new lease (seconds) as reply
          */
         char *mesg = buf;
-        int rv;
+        int rv, lease;
 
         if (size > 0) {
-                int lease;
+                if (nfsd_serv)
+                        return -EBUSY;
                 rv = get_int(&mesg, &lease);
                 if (rv)
                         return rv;
@@ -735,24 +747,52 @@ static ssize_t write_leasetime(struct file *file, char *buf, size_t size)
         return strlen(buf);
 }
 
-static ssize_t write_recoverydir(struct file *file, char *buf, size_t size)
+static ssize_t write_leasetime(struct file *file, char *buf, size_t size)
+{
+        ssize_t rv;
+
+        mutex_lock(&nfsd_mutex);
+        rv = __write_leasetime(file, buf, size);
+        mutex_unlock(&nfsd_mutex);
+        return rv;
+}
+
+extern char *nfs4_recoverydir(void);
+
+static ssize_t __write_recoverydir(struct file *file, char *buf, size_t size)
 {
         char *mesg = buf;
         char *recdir;
         int len, status;
 
-        if (size == 0 || size > PATH_MAX || buf[size-1] != '\n')
-                return -EINVAL;
-        buf[size-1] = 0;
+        if (size > 0) {
+                if (nfsd_serv)
+                        return -EBUSY;
+                if (size > PATH_MAX || buf[size-1] != '\n')
+                        return -EINVAL;
+                buf[size-1] = 0;
 
-        recdir = mesg;
-        len = qword_get(&mesg, recdir, size);
-        if (len <= 0)
-                return -EINVAL;
+                recdir = mesg;
+                len = qword_get(&mesg, recdir, size);
+                if (len <= 0)
+                        return -EINVAL;
 
-        status = nfs4_reset_recoverydir(recdir);
+                status = nfs4_reset_recoverydir(recdir);
+        }
+        sprintf(buf, "%s\n", nfs4_recoverydir());
         return strlen(buf);
 }
+
+static ssize_t write_recoverydir(struct file *file, char *buf, size_t size)
+{
+        ssize_t rv;
+
+        mutex_lock(&nfsd_mutex);
+        rv = __write_recoverydir(file, buf, size);
+        mutex_unlock(&nfsd_mutex);
+        return rv;
+}
+
 #endif
 
 /*----------------------------------------------------------------------------*/
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index 512bd04c6dda..929af233510e 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -70,6 +70,14 @@ static DEFINE_SPINLOCK(nfsd_call_lock);
  * Transitions of the thread count between zero and non-zero are of particular
  * interest since the svc_serv needs to be created and initialized at that
  * point, or freed.
+ *
+ * Finally, the nfsd_mutex also protects some of the global variables that are
+ * accessed when nfsd starts and that are settable via the write_* routines in
+ * nfsctl.c. In particular:
+ *
+ *      user_recovery_dirname
+ *      user_lease_time
+ *      nfsd_versions
  */
 DEFINE_MUTEX(nfsd_mutex);
 struct svc_serv                 *nfsd_serv;