nilfs2: add compat ioctl

The current FS_IOC_GETFLAGS/SETFLAGS/GETVERSION will fail if
application is 32 bit and kernel is 64 bit.

This issue is avoidable by adding compat_ioctl method.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

1 files changed, 21 insertions, 0 deletions

diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index 3aad6413aba4..d89173edd7fe 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -26,6 +26,7 @@
 #include <linux/capability.h>   /* capable() */
 #include <linux/uaccess.h>      /* copy_from_user(), copy_to_user() */
 #include <linux/vmalloc.h>
+#include <linux/compat.h>       /* compat_ptr() */
 #include <linux/mount.h>        /* mnt_want_write(), mnt_drop_write() */
 #include <linux/nilfs2_fs.h>
 #include "nilfs.h"
@@ -766,3 +767,23 @@ long nilfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
                 return -ENOTTY;
         }
 }
+
+#ifdef CONFIG_COMPAT
+long nilfs_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+        switch (cmd) {
+        case FS_IOC32_GETFLAGS:
+                cmd = FS_IOC_GETFLAGS;
+                break;
+        case FS_IOC32_SETFLAGS:
+                cmd = FS_IOC_SETFLAGS;
+                break;
+        case FS_IOC32_GETVERSION:
+                cmd = FS_IOC_GETVERSION;
+                break;
+        default:
+                return -ENOIOCTLCMD;
+        }
+        return nilfs_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
+}
+#endif