53bb724f94
After a bit of poking around wondering why my 32-bit user-space can't seem to send a proper ioctl(BLKPG) to an MTD on my 64-bit kernel (ARM64), I noticed that struct blkpg_ioctl_arg is actually pretty unsuitable for use in the ioctl() ABI, due to its use of raw pointers, and its lack of alignment/packing restrictions (32-bit arch'es tend to pack the 4 fields into 4 32-bit words, whereas 64-bit arch'es would add padding after the third int, and make this 6 32-bit words). Anyway, this means BLKPG deserves some special compat_ioctl handling. Do the conversion in a small shim for MTD. block/compat_ioctl.c already has compat support for the block subsystem, but it does so by a re-marshalling data to/from user-space (see compat_blkpg_ioctl()). Personally, I think this approach is cleaner. Tested only on MTD, with an ARM32 user space on an ARM64 kernel. Signed-off-by: Brian Norris <computersforpeace@gmail.com>
60 lines
1.6 KiB
C
60 lines
1.6 KiB
C
#ifndef _UAPI__LINUX_BLKPG_H
|
|
#define _UAPI__LINUX_BLKPG_H
|
|
|
|
/*
|
|
* Partition table and disk geometry handling
|
|
*
|
|
* A single ioctl with lots of subfunctions:
|
|
*
|
|
* Device number stuff:
|
|
* get_whole_disk() (given the device number of a partition,
|
|
* find the device number of the encompassing disk)
|
|
* get_all_partitions() (given the device number of a disk, return the
|
|
* device numbers of all its known partitions)
|
|
*
|
|
* Partition stuff:
|
|
* add_partition()
|
|
* delete_partition()
|
|
* test_partition_in_use() (also for test_disk_in_use)
|
|
*
|
|
* Geometry stuff:
|
|
* get_geometry()
|
|
* set_geometry()
|
|
* get_bios_drivedata()
|
|
*
|
|
* For today, only the partition stuff - aeb, 990515
|
|
*/
|
|
#include <linux/compiler.h>
|
|
#include <linux/ioctl.h>
|
|
|
|
#define BLKPG _IO(0x12,105)
|
|
|
|
/* The argument structure */
|
|
struct blkpg_ioctl_arg {
|
|
int op;
|
|
int flags;
|
|
int datalen;
|
|
void __user *data;
|
|
};
|
|
|
|
/* The subfunctions (for the op field) */
|
|
#define BLKPG_ADD_PARTITION 1
|
|
#define BLKPG_DEL_PARTITION 2
|
|
#define BLKPG_RESIZE_PARTITION 3
|
|
|
|
/* Sizes of name fields. Unused at present. */
|
|
#define BLKPG_DEVNAMELTH 64
|
|
#define BLKPG_VOLNAMELTH 64
|
|
|
|
/* The data structure for ADD_PARTITION and DEL_PARTITION */
|
|
struct blkpg_partition {
|
|
long long start; /* starting offset in bytes */
|
|
long long length; /* length in bytes */
|
|
int pno; /* partition number */
|
|
char devname[BLKPG_DEVNAMELTH]; /* partition name, like sda5 or c0d1p2,
|
|
to be used in kernel messages */
|
|
char volname[BLKPG_VOLNAMELTH]; /* volume label */
|
|
};
|
|
|
|
#endif /* _UAPI__LINUX_BLKPG_H */
|