linux-headers/linux/loop.h
2023-06-07 11:35:51 +00:00

121 lines
3.3 KiB
C

/* SPDX-License-Identifier: GPL-1.0+ WITH Linux-syscall-note */
/*
* Copyright 1993 by Theodore Ts'o.
*/
#ifndef _LINUX_LOOP_H
#define _LINUX_LOOP_H
#define LO_NAME_SIZE 64
#define LO_KEY_SIZE 32
/*
* Loop flags
*/
enum {
LO_FLAGS_READ_ONLY = 1,
LO_FLAGS_AUTOCLEAR = 4,
LO_FLAGS_PARTSCAN = 8,
LO_FLAGS_DIRECT_IO = 16,
};
/* LO_FLAGS that can be set using LOOP_SET_STATUS(64) */
#define LOOP_SET_STATUS_SETTABLE_FLAGS (LO_FLAGS_AUTOCLEAR | LO_FLAGS_PARTSCAN)
/* LO_FLAGS that can be cleared using LOOP_SET_STATUS(64) */
#define LOOP_SET_STATUS_CLEARABLE_FLAGS (LO_FLAGS_AUTOCLEAR)
/* LO_FLAGS that can be set using LOOP_CONFIGURE */
#define LOOP_CONFIGURE_SETTABLE_FLAGS (LO_FLAGS_READ_ONLY | LO_FLAGS_AUTOCLEAR \
| LO_FLAGS_PARTSCAN | LO_FLAGS_DIRECT_IO)
#include <asm/posix_types.h> /* for __kernel_old_dev_t */
#include <linux/types.h> /* for __u64 */
/* Backwards compatibility version */
struct loop_info {
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; /* obsolete, ignored */
int lo_encrypt_key_size; /* ioctl w/o */
int lo_flags;
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;
__u64 lo_sizelimit;/* bytes, 0 == max available */
__u32 lo_number; /* ioctl r/o */
__u32 lo_encrypt_type; /* obsolete, ignored */
__u32 lo_encrypt_key_size; /* ioctl w/o */
__u32 lo_flags;
__u8 lo_file_name[LO_NAME_SIZE];
__u8 lo_crypt_name[LO_NAME_SIZE];
__u8 lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */
__u64 lo_init[2];
};
/**
* struct loop_config - Complete configuration for a loop device.
* @fd: fd of the file to be used as a backing file for the loop device.
* @block_size: block size to use; ignored if 0.
* @info: struct loop_info64 to configure the loop device with.
*
* This structure is used with the LOOP_CONFIGURE ioctl, and can be used to
* atomically setup and configure all loop device parameters at once.
*/
struct loop_config {
__u32 fd;
__u32 block_size;
struct loop_info64 info;
__u64 __reserved[8];
};
/*
* Loop filter types
*/
#define LO_CRYPT_NONE 0
#define LO_CRYPT_XOR 1
#define LO_CRYPT_DES 2
#define LO_CRYPT_FISH2 3 /* Twofish encryption */
#define LO_CRYPT_BLOW 4
#define LO_CRYPT_CAST128 5
#define LO_CRYPT_IDEA 6
#define LO_CRYPT_DUMMY 9
#define LO_CRYPT_SKIPJACK 10
#define LO_CRYPT_CRYPTOAPI 18
#define MAX_LO_CRYPT 20
/*
* 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_STATUS64 0x4C04
#define LOOP_GET_STATUS64 0x4C05
#define LOOP_CHANGE_FD 0x4C06
#define LOOP_SET_CAPACITY 0x4C07
#define LOOP_SET_DIRECT_IO 0x4C08
#define LOOP_SET_BLOCK_SIZE 0x4C09
#define LOOP_CONFIGURE 0x4C0A
/* /dev/loop-control interface */
#define LOOP_CTL_ADD 0x4C80
#define LOOP_CTL_REMOVE 0x4C81
#define LOOP_CTL_GET_FREE 0x4C82
#endif /* _LINUX_LOOP_H */