1 /* SPDX-License-Identifier: GPL-1.0+ WITH Linux-syscall-note */ 2 /* 3 * include/linux/loop.h 4 * 5 * Written by Theodore Ts'o, 3/29/93. 6 * 7 * Copyright 1993 by Theodore Ts'o. Redistribution of this file is 8 * permitted under the GNU General Public License. 9 */ 10 #ifndef _UAPI_LINUX_LOOP_H 11 #define _UAPI_LINUX_LOOP_H 12 13 14 #define LO_NAME_SIZE 64 15 #define LO_KEY_SIZE 32 16 17 18 /* 19 * Loop flags 20 */ 21 enum { 22 LO_FLAGS_READ_ONLY = 1, 23 LO_FLAGS_AUTOCLEAR = 4, 24 LO_FLAGS_PARTSCAN = 8, 25 LO_FLAGS_DIRECT_IO = 16, 26 }; 27 28 /* LO_FLAGS that can be set using LOOP_SET_STATUS(64) */ 29 #define LOOP_SET_STATUS_SETTABLE_FLAGS (LO_FLAGS_AUTOCLEAR | LO_FLAGS_PARTSCAN) 30 31 /* LO_FLAGS that can be cleared using LOOP_SET_STATUS(64) */ 32 #define LOOP_SET_STATUS_CLEARABLE_FLAGS (LO_FLAGS_AUTOCLEAR) 33 34 /* LO_FLAGS that can be set using LOOP_CONFIGURE */ 35 #define LOOP_CONFIGURE_SETTABLE_FLAGS (LO_FLAGS_READ_ONLY | LO_FLAGS_AUTOCLEAR \ 36 | LO_FLAGS_PARTSCAN | LO_FLAGS_DIRECT_IO) 37 38 #include <asm/posix_types.h> /* for __kernel_old_dev_t */ 39 #include <linux/types.h> /* for __u64 */ 40 41 /* Backwards compatibility version */ 42 struct loop_info { 43 int lo_number; /* ioctl r/o */ 44 __kernel_old_dev_t lo_device; /* ioctl r/o */ 45 unsigned long lo_inode; /* ioctl r/o */ 46 __kernel_old_dev_t lo_rdevice; /* ioctl r/o */ 47 int lo_offset; 48 int lo_encrypt_type; /* obsolete, ignored */ 49 int lo_encrypt_key_size; /* ioctl w/o */ 50 int lo_flags; 51 char lo_name[LO_NAME_SIZE]; 52 unsigned char lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */ 53 unsigned long lo_init[2]; 54 char reserved[4]; 55 }; 56 57 struct loop_info64 { 58 __u64 lo_device; /* ioctl r/o */ 59 __u64 lo_inode; /* ioctl r/o */ 60 __u64 lo_rdevice; /* ioctl r/o */ 61 __u64 lo_offset; 62 __u64 lo_sizelimit;/* bytes, 0 == max available */ 63 __u32 lo_number; /* ioctl r/o */ 64 __u32 lo_encrypt_type; /* obsolete, ignored */ 65 __u32 lo_encrypt_key_size; /* ioctl w/o */ 66 __u32 lo_flags; 67 __u8 lo_file_name[LO_NAME_SIZE]; 68 __u8 lo_crypt_name[LO_NAME_SIZE]; 69 __u8 lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */ 70 __u64 lo_init[2]; 71 }; 72 73 /** 74 * struct loop_config - Complete configuration for a loop device. 75 * @fd: fd of the file to be used as a backing file for the loop device. 76 * @block_size: block size to use; ignored if 0. 77 * @info: struct loop_info64 to configure the loop device with. 78 * 79 * This structure is used with the LOOP_CONFIGURE ioctl, and can be used to 80 * atomically setup and configure all loop device parameters at once. 81 */ 82 struct loop_config { 83 __u32 fd; 84 __u32 block_size; 85 struct loop_info64 info; 86 __u64 __reserved[8]; 87 }; 88 89 /* 90 * Loop filter types 91 */ 92 93 #define LO_CRYPT_NONE 0 94 #define LO_CRYPT_XOR 1 95 #define LO_CRYPT_DES 2 96 #define LO_CRYPT_FISH2 3 /* Twofish encryption */ 97 #define LO_CRYPT_BLOW 4 98 #define LO_CRYPT_CAST128 5 99 #define LO_CRYPT_IDEA 6 100 #define LO_CRYPT_DUMMY 9 101 #define LO_CRYPT_SKIPJACK 10 102 #define LO_CRYPT_CRYPTOAPI 18 103 #define MAX_LO_CRYPT 20 104 105 /* 106 * IOCTL commands --- we will commandeer 0x4C ('L') 107 */ 108 109 #define LOOP_SET_FD 0x4C00 110 #define LOOP_CLR_FD 0x4C01 111 #define LOOP_SET_STATUS 0x4C02 112 #define LOOP_GET_STATUS 0x4C03 113 #define LOOP_SET_STATUS64 0x4C04 114 #define LOOP_GET_STATUS64 0x4C05 115 #define LOOP_CHANGE_FD 0x4C06 116 #define LOOP_SET_CAPACITY 0x4C07 117 #define LOOP_SET_DIRECT_IO 0x4C08 118 #define LOOP_SET_BLOCK_SIZE 0x4C09 119 #define LOOP_CONFIGURE 0x4C0A 120 121 /* /dev/loop-control interface */ 122 #define LOOP_CTL_ADD 0x4C80 123 #define LOOP_CTL_REMOVE 0x4C81 124 #define LOOP_CTL_GET_FREE 0x4C82 125 #endif /* _UAPI_LINUX_LOOP_H */ 126