diff mbox

[2/3] VFAT GET_VOLUME_ID ioctl

Message ID 1368694144-20863-2-git-send-email-dmitry.pervushin@linaro.org
State New
Headers show

Commit Message

Dmitry Pervushin May 16, 2013, 8:49 a.m. UTC 
Add VFAT_GET_VOLUME_ID ioctl, which returns the volume id via passed
pointer to u32
---
 fs/fat/dir.c                  | 22 +++++++++++++++++++---
 include/uapi/linux/msdos_fs.h |  1 +
 2 files changed, 20 insertions(+), 3 deletions(-)
diff mbox

Patch

diff --git a/fs/fat/dir.c b/fs/fat/dir.c
index eef52ee..37849b1 100644
--- a/fs/fat/dir.c
+++ b/fs/fat/dir.c
@@ -783,6 +783,24 @@  static int fat_ioctl_volume_id(struct inode *dir)
 	return sbi->vol_id;
 }
 
+static long fat_dir_generic_ioctl(struct file *filp, unsigned int cmd,
+				  unsigned long arg)
+{
+	struct inode *inode = file_inode(filp);
+	u32 id;
+
+	switch (cmd) {
+	case VFAT_IOCTL_GET_VOLUME_ID_BROKEN:
+		return fat_ioctl_volume_id(inode);
+	case VFAT_IOCTL_GET_VOLUME_ID:
+		if (inode->i_ino != MSDOS_ROOT_INO)
+			return -EINVAL;
+		id = fat_ioctl_volume_id(inode);
+		return copy_to_user((u32 *)arg, &id, sizeof(id));
+	}
+	return fat_generic_ioctl(filp, cmd, arg);
+}
+
 static long fat_dir_ioctl(struct file *filp, unsigned int cmd,
 			  unsigned long arg)
 {
@@ -799,10 +817,8 @@  static long fat_dir_ioctl(struct file *filp, unsigned int cmd,
 		short_only = 0;
 		both = 1;
 		break;
-	case VFAT_IOCTL_GET_VOLUME_ID_BROKEN:
-		return fat_ioctl_volume_id(inode);
 	default:
-		return fat_generic_ioctl(filp, cmd, arg);
+		return fat_dir_generic_ioctl(filp, cmd, arg);
 	}
 
 	if (!access_ok(VERIFY_WRITE, d1, sizeof(struct __fat_dirent[2])))
diff --git a/include/uapi/linux/msdos_fs.h b/include/uapi/linux/msdos_fs.h
index fddfc61..b322512 100644
--- a/include/uapi/linux/msdos_fs.h
+++ b/include/uapi/linux/msdos_fs.h
@@ -105,6 +105,7 @@  struct __fat_dirent {
 #define FAT_IOCTL_GET_ATTRIBUTES	_IOR('r', 0x10, __u32)
 #define FAT_IOCTL_SET_ATTRIBUTES	_IOW('r', 0x11, __u32)
 #define VFAT_IOCTL_GET_VOLUME_ID_BROKEN	_IOR('r', 0x12, __u32)
+#define VFAT_IOCTL_GET_VOLUME_ID	_IOR('r', 0x13, __u32)
 
 struct fat_boot_sector {
 	__u8	ignored[3];	/* Boot strap short or near jump */