1 files changed, 45 insertions, 6 deletions

diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 51844048937f..4e042105fb6e 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -39,6 +39,7 @@ enum {
         NFSD_Versions,
         NFSD_Ports,
         NFSD_MaxBlkSize,
+        NFSD_MaxConnections,
         NFSD_SupportedEnctypes,
         /*
          * The below MUST come last.  Otherwise we leave a hole in nfsd_files[]
@@ -62,6 +63,7 @@ static ssize_t write_pool_threads(struct file *file, char *buf, size_t size);
 static ssize_t write_versions(struct file *file, char *buf, size_t size);
 static ssize_t write_ports(struct file *file, char *buf, size_t size);
 static ssize_t write_maxblksize(struct file *file, char *buf, size_t size);
+static ssize_t write_maxconn(struct file *file, char *buf, size_t size);
 #ifdef CONFIG_NFSD_V4
 static ssize_t write_leasetime(struct file *file, char *buf, size_t size);
 static ssize_t write_gracetime(struct file *file, char *buf, size_t size);
@@ -77,6 +79,7 @@ static ssize_t (*write_op[])(struct file *, char *, size_t) = {
         [NFSD_Versions] = write_versions,
         [NFSD_Ports] = write_ports,
         [NFSD_MaxBlkSize] = write_maxblksize,
+        [NFSD_MaxConnections] = write_maxconn,
 #ifdef CONFIG_NFSD_V4
         [NFSD_Leasetime] = write_leasetime,
         [NFSD_Gracetime] = write_gracetime,
@@ -369,8 +372,7 @@ static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
 
         if (maxsize < NFS_FHSIZE)
                 return -EINVAL;
-        if (maxsize > NFS3_FHSIZE)
-                maxsize = NFS3_FHSIZE;
+        maxsize = min(maxsize, NFS3_FHSIZE);
 
         if (qword_get(&mesg, mesg, size)>0)
                 return -EINVAL;
@@ -871,10 +873,8 @@ static ssize_t write_maxblksize(struct file *file, char *buf, size_t size)
                 /* force bsize into allowed range and
                  * required alignment.
                  */
-                if (bsize < 1024)
-                        bsize = 1024;
-                if (bsize > NFSSVC_MAXBLKSIZE)
-                        bsize = NFSSVC_MAXBLKSIZE;
+                bsize = max_t(int, bsize, 1024);
+                bsize = min_t(int, bsize, NFSSVC_MAXBLKSIZE);
                 bsize &= ~(1024-1);
                 mutex_lock(&nfsd_mutex);
                 if (nn->nfsd_serv) {
@@ -889,6 +889,44 @@ static ssize_t write_maxblksize(struct file *file, char *buf, size_t size)
                                                         nfsd_max_blksize);
 }
 
+/**
+ * write_maxconn - Set or report the current max number of connections
+ *
+ * Input:
+ *                      buf:            ignored
+ *                      size:           zero
+ * OR
+ *
+ * Input:
+ *                      buf:            C string containing an unsigned
+ *                                      integer value representing the new
+ *                                      number of max connections
+ *                      size:           non-zero length of C string in @buf
+ * Output:
+ *      On success:     passed-in buffer filled with '\n'-terminated C string
+ *                      containing numeric value of max_connections setting
+ *                      for this net namespace;
+ *                      return code is the size in bytes of the string
+ *      On error:       return code is zero or a negative errno value
+ */
+static ssize_t write_maxconn(struct file *file, char *buf, size_t size)
+{
+        char *mesg = buf;
+        struct net *net = file->f_dentry->d_sb->s_fs_info;
+        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+        unsigned int maxconn = nn->max_connections;
+
+        if (size > 0) {
+                int rv = get_uint(&mesg, &maxconn);
+
+                if (rv)
+                        return rv;
+                nn->max_connections = maxconn;
+        }
+
+        return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%u\n", maxconn);
+}
+
 #ifdef CONFIG_NFSD_V4
 static ssize_t __nfsd4_write_time(struct file *file, char *buf, size_t size,
                                   time_t *time, struct nfsd_net *nn)
@@ -1064,6 +1102,7 @@ static int nfsd_fill_super(struct super_block * sb, void * data, int silent)
                 [NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR},
                 [NFSD_Ports] = {"portlist", &transaction_ops, S_IWUSR|S_IRUGO},
                 [NFSD_MaxBlkSize] = {"max_block_size", &transaction_ops, S_IWUSR|S_IRUGO},
+                [NFSD_MaxConnections] = {"max_connections", &transaction_ops, S_IWUSR|S_IRUGO},
 #if defined(CONFIG_SUNRPC_GSS) || defined(CONFIG_SUNRPC_GSS_MODULE)
                 [NFSD_SupportedEnctypes] = {"supported_krb5_enctypes", &supported_enctypes_ops, S_IRUGO},
 #endif /* CONFIG_SUNRPC_GSS or CONFIG_SUNRPC_GSS_MODULE */