[PATCH] struct loop_info64 with __u64

(i) Replace in struct loop_info the dev_t field by __kernel_old_dev_t,
where this type is defined in <asm/posix_types.h>, so that problems
with a differently sized dev_t in userspace are avoided.

(ii) Introduce a new loop_info64, with __u64 device, inode and offset
fields.

1 files changed, 37 insertions, 34 deletions

diff --git a/include/linux/loop.h b/include/linux/loop.h
index fe28a0ee8f34..f2e8d775f43a 100644
--- a/include/linux/loop.h
+++ b/include/linux/loop.h
@@ -1,8 +1,6 @@
 #ifndef _LINUX_LOOP_H
 #define _LINUX_LOOP_H
 
-#include <linux/kdev_t.h>
-
 /*
  * include/linux/loop.h
  *
@@ -74,34 +72,37 @@ typedef	int (* transfer_proc_t)(struct loop_device *, int cmd,
 #define LO_FLAGS_READ_ONLY	2
 #define LO_FLAGS_BH_REMAP	4
 
-/* 
- * Note that this structure gets the wrong offsets when directly used
- * from a glibc program, because glibc has a 32bit dev_t.
- * Prevent people from shooting in their own foot.  
- */
-#if __GLIBC__ >= 2 && !defined(dev_t)
-#error "Wrong dev_t in loop.h"
-#endif 
-
-/*
- *	This uses kdev_t because glibc currently has no appropiate
- *	conversion version for the loop ioctls. 
- * 	The situation is very unpleasant	
- */
+#include <asm/posix_types.h>	/* for __kernel_old_dev_t */
+#include <asm/types.h>		/* for __u64 */
 
+/* Backwards compatibility version */
 struct loop_info {
-	int		lo_number;	/* ioctl r/o */
-	dev_t		lo_device; 	/* ioctl r/o */
-	unsigned long	lo_inode; 	/* ioctl r/o */
-	dev_t		lo_rdevice; 	/* ioctl r/o */
-	int		lo_offset;
-	int		lo_encrypt_type;
-	int		lo_encrypt_key_size; 	/* ioctl w/o */
-	int		lo_flags;	/* ioctl r/o */
-	char		lo_name[LO_NAME_SIZE];
-	unsigned char	lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */
-	unsigned long	lo_init[2];
-	char		reserved[4];
+	int		   lo_number;		/* ioctl r/o */
+	__kernel_old_dev_t lo_device; 		/* ioctl r/o */
+	unsigned long	   lo_inode; 		/* ioctl r/o */
+	__kernel_old_dev_t lo_rdevice; 		/* ioctl r/o */
+	int		   lo_offset;
+	int		   lo_encrypt_type;
+	int		   lo_encrypt_key_size; 	/* ioctl w/o */
+	int		   lo_flags;			/* ioctl r/o */
+	char		   lo_name[LO_NAME_SIZE];
+	unsigned char	   lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */
+	unsigned long	   lo_init[2];
+	char		   reserved[4];
+};
+
+struct loop_info64 {
+	__u64		   lo_device; 		/* ioctl r/o */
+	__u64		   lo_inode; 		/* ioctl r/o */
+	__u64		   lo_rdevice; 		/* ioctl r/o */
+	__u64		   lo_offset;
+	__u32		   lo_number;		/* ioctl r/o */
+	__u32		   lo_encrypt_type;
+	__u32		   lo_encrypt_key_size; 	/* ioctl w/o */
+	__u32		   lo_flags;			/* ioctl r/o */
+	__u8		   lo_name[LO_NAME_SIZE];
+	__u8		   lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */
+	__u64		   lo_init[2];
 };
 
 /*
@@ -125,7 +126,7 @@ struct loop_func_table {
 	int number; 	/* filter type */ 
 	int (*transfer)(struct loop_device *lo, int cmd, char *raw_buf,
 			char *loop_buf, int size, sector_t real_block);
-	int (*init)(struct loop_device *, struct loop_info *); 
+	int (*init)(struct loop_device *, const struct loop_info64 *); 
 	/* release is called from loop_unregister_transfer or clr_fd */
 	int (*release)(struct loop_device *); 
 	int (*ioctl)(struct loop_device *, int cmd, unsigned long arg);
@@ -134,7 +135,7 @@ struct loop_func_table {
 	void (*unlock)(struct loop_device *);
 }; 
 
-int  loop_register_transfer(struct loop_func_table *funcs);
+int loop_register_transfer(struct loop_func_table *funcs);
 int loop_unregister_transfer(int number); 
 
 #endif
@@ -142,9 +143,11 @@ int loop_unregister_transfer(int number);
  * IOCTL commands --- we will commandeer 0x4C ('L')
  */
 
-#define LOOP_SET_FD	0x4C00
-#define LOOP_CLR_FD	0x4C01
-#define LOOP_SET_STATUS	0x4C02
-#define LOOP_GET_STATUS	0x4C03
+#define LOOP_SET_FD		0x4C00
+#define LOOP_CLR_FD		0x4C01
+#define LOOP_SET_STATUS		0x4C02
+#define LOOP_GET_STATUS		0x4C03
+#define LOOP_SET_STATUS64	0x4C04
+#define LOOP_GET_STATUS64	0x4C05
 
 #endif