loop.h (3395B) - Raw
1 /* SPDX-License-Identifier: GPL-1.0+ WITH Linux-syscall-note */ 2 /* 3 * Copyright 1993 by Theodore Ts'o. 4 */ 5 #ifndef _LINUX_LOOP_H 6 #define _LINUX_LOOP_H 7 8 9 #define LO_NAME_SIZE 64 10 #define LO_KEY_SIZE 32 11 12 13 /* 14 * Loop flags 15 */ 16 enum { 17 LO_FLAGS_READ_ONLY = 1, 18 LO_FLAGS_AUTOCLEAR = 4, 19 LO_FLAGS_PARTSCAN = 8, 20 LO_FLAGS_DIRECT_IO = 16, 21 }; 22 23 /* LO_FLAGS that can be set using LOOP_SET_STATUS(64) */ 24 #define LOOP_SET_STATUS_SETTABLE_FLAGS (LO_FLAGS_AUTOCLEAR | LO_FLAGS_PARTSCAN) 25 26 /* LO_FLAGS that can be cleared using LOOP_SET_STATUS(64) */ 27 #define LOOP_SET_STATUS_CLEARABLE_FLAGS (LO_FLAGS_AUTOCLEAR) 28 29 /* LO_FLAGS that can be set using LOOP_CONFIGURE */ 30 #define LOOP_CONFIGURE_SETTABLE_FLAGS (LO_FLAGS_READ_ONLY | LO_FLAGS_AUTOCLEAR \ 31 | LO_FLAGS_PARTSCAN | LO_FLAGS_DIRECT_IO) 32 33 #include <asm/posix_types.h> /* for __kernel_old_dev_t */ 34 #include <linux/types.h> /* for __u64 */ 35 36 /* Backwards compatibility version */ 37 struct loop_info { 38 int lo_number; /* ioctl r/o */ 39 __kernel_old_dev_t lo_device; /* ioctl r/o */ 40 unsigned long lo_inode; /* ioctl r/o */ 41 __kernel_old_dev_t lo_rdevice; /* ioctl r/o */ 42 int lo_offset; 43 int lo_encrypt_type; /* obsolete, ignored */ 44 int lo_encrypt_key_size; /* ioctl w/o */ 45 int lo_flags; 46 char lo_name[LO_NAME_SIZE]; 47 unsigned char lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */ 48 unsigned long lo_init[2]; 49 char reserved[4]; 50 }; 51 52 struct loop_info64 { 53 __u64 lo_device; /* ioctl r/o */ 54 __u64 lo_inode; /* ioctl r/o */ 55 __u64 lo_rdevice; /* ioctl r/o */ 56 __u64 lo_offset; 57 __u64 lo_sizelimit;/* bytes, 0 == max available */ 58 __u32 lo_number; /* ioctl r/o */ 59 __u32 lo_encrypt_type; /* obsolete, ignored */ 60 __u32 lo_encrypt_key_size; /* ioctl w/o */ 61 __u32 lo_flags; 62 __u8 lo_file_name[LO_NAME_SIZE]; 63 __u8 lo_crypt_name[LO_NAME_SIZE]; 64 __u8 lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */ 65 __u64 lo_init[2]; 66 }; 67 68 /** 69 * struct loop_config - Complete configuration for a loop device. 70 * @fd: fd of the file to be used as a backing file for the loop device. 71 * @block_size: block size to use; ignored if 0. 72 * @info: struct loop_info64 to configure the loop device with. 73 * 74 * This structure is used with the LOOP_CONFIGURE ioctl, and can be used to 75 * atomically setup and configure all loop device parameters at once. 76 */ 77 struct loop_config { 78 __u32 fd; 79 __u32 block_size; 80 struct loop_info64 info; 81 __u64 __reserved[8]; 82 }; 83 84 /* 85 * Loop filter types 86 */ 87 88 #define LO_CRYPT_NONE 0 89 #define LO_CRYPT_XOR 1 90 #define LO_CRYPT_DES 2 91 #define LO_CRYPT_FISH2 3 /* Twofish encryption */ 92 #define LO_CRYPT_BLOW 4 93 #define LO_CRYPT_CAST128 5 94 #define LO_CRYPT_IDEA 6 95 #define LO_CRYPT_DUMMY 9 96 #define LO_CRYPT_SKIPJACK 10 97 #define LO_CRYPT_CRYPTOAPI 18 98 #define MAX_LO_CRYPT 20 99 100 /* 101 * IOCTL commands --- we will commandeer 0x4C ('L') 102 */ 103 104 #define LOOP_SET_FD 0x4C00 105 #define LOOP_CLR_FD 0x4C01 106 #define LOOP_SET_STATUS 0x4C02 107 #define LOOP_GET_STATUS 0x4C03 108 #define LOOP_SET_STATUS64 0x4C04 109 #define LOOP_GET_STATUS64 0x4C05 110 #define LOOP_CHANGE_FD 0x4C06 111 #define LOOP_SET_CAPACITY 0x4C07 112 #define LOOP_SET_DIRECT_IO 0x4C08 113 #define LOOP_SET_BLOCK_SIZE 0x4C09 114 #define LOOP_CONFIGURE 0x4C0A 115 116 /* /dev/loop-control interface */ 117 #define LOOP_CTL_ADD 0x4C80 118 #define LOOP_CTL_REMOVE 0x4C81 119 #define LOOP_CTL_GET_FREE 0x4C82 120 #endif /* _LINUX_LOOP_H */