1 files changed, 36 insertions, 6 deletions

diff --git a/drivers/usb/core/inode.c b/drivers/usb/core/inode.c
index cd4f11157280..83a373e9cc36 100644
--- a/drivers/usb/core/inode.c
+++ b/drivers/usb/core/inode.c
@@ -38,10 +38,15 @@
 #include <linux/usbdevice_fs.h>
 #include <linux/parser.h>
 #include <linux/notifier.h>
+#include <linux/seq_file.h>
 #include <asm/byteorder.h>
 #include "usb.h"
 #include "hcd.h"
 
+#define USBFS_DEFAULT_DEVMODE (S_IWUSR | S_IRUGO)
+#define USBFS_DEFAULT_BUSMODE (S_IXUGO | S_IRUGO)
+#define USBFS_DEFAULT_LISTMODE S_IRUGO
+
 static struct super_operations usbfs_ops;
 static const struct file_operations default_file_operations;
 static struct vfsmount *usbfs_mount;
@@ -57,9 +62,33 @@ static uid_t listuid;	/* = 0 */
 static gid_t devgid;    /* = 0 */
 static gid_t busgid;    /* = 0 */
 static gid_t listgid;   /* = 0 */
-static umode_t devmode = S_IWUSR | S_IRUGO;
-static umode_t busmode = S_IXUGO | S_IRUGO;
-static umode_t listmode = S_IRUGO;
+static umode_t devmode = USBFS_DEFAULT_DEVMODE;
+static umode_t busmode = USBFS_DEFAULT_BUSMODE;
+static umode_t listmode = USBFS_DEFAULT_LISTMODE;
+
+static int usbfs_show_options(struct seq_file *seq, struct vfsmount *mnt)
+{
+        if (devuid != 0)
+                seq_printf(seq, ",devuid=%u", devuid);
+        if (devgid != 0)
+                seq_printf(seq, ",devgid=%u", devgid);
+        if (devmode != USBFS_DEFAULT_DEVMODE)
+                seq_printf(seq, ",devmode=%o", devmode);
+        if (busuid != 0)
+                seq_printf(seq, ",busuid=%u", busuid);
+        if (busgid != 0)
+                seq_printf(seq, ",busgid=%u", busgid);
+        if (busmode != USBFS_DEFAULT_BUSMODE)
+                seq_printf(seq, ",busmode=%o", busmode);
+        if (listuid != 0)
+                seq_printf(seq, ",listuid=%u", listuid);
+        if (listgid != 0)
+                seq_printf(seq, ",listgid=%u", listgid);
+        if (listmode != USBFS_DEFAULT_LISTMODE)
+                seq_printf(seq, ",listmode=%o", listmode);
+
+        return 0;
+}
 
 enum {
         Opt_devuid, Opt_devgid, Opt_devmode,
@@ -93,9 +122,9 @@ static int parse_options(struct super_block *s, char *data)
         devgid = 0;
         busgid = 0;
         listgid = 0;
-        devmode = S_IWUSR | S_IRUGO;
-        busmode = S_IXUGO | S_IRUGO;
-        listmode = S_IRUGO;
+        devmode = USBFS_DEFAULT_DEVMODE;
+        busmode = USBFS_DEFAULT_BUSMODE;
+        listmode = USBFS_DEFAULT_LISTMODE;
 
         while ((p = strsep(&data, ",")) != NULL) {
                 substring_t args[MAX_OPT_ARGS];
@@ -418,6 +447,7 @@ static struct super_operations usbfs_ops = {
         .statfs =       simple_statfs,
         .drop_inode =   generic_delete_inode,
         .remount_fs =   remount,
+        .show_options = usbfs_show_options,
 };
 
 static int usbfs_fill_super(struct super_block *sb, void *data, int silent)