1 #ifndef _LINUX_LOOP_H 2 #define _LINUX_LOOP_H 3 4 /* 5 * include/linux/loop.h 6 * 7 * Written by Theodore Ts'o, 3/29/93. 8 * 9 * Copyright 1993 by Theodore Ts'o. Redistribution of this file is 10 * permitted under the GNU General Public License. 11 */ 12 13 #define LO_NAME_SIZE 64 14 #define LO_KEY_SIZE 32 15 16 #ifdef __KERNEL__ 17 #include <linux/bio.h> 18 #include <linux/blkdev.h> 19 #include <linux/spinlock.h> 20 #include <linux/mutex.h> 21 22 /* Possible states of device */ 23 enum { 24 Lo_unbound, 25 Lo_bound, 26 Lo_rundown, 27 }; 28 29 struct loop_func_table; 30 31 struct loop_device { 32 int lo_number; 33 int lo_refcnt; 34 loff_t lo_offset; 35 loff_t lo_sizelimit; 36 int lo_flags; 37 int (*transfer)(struct loop_device *, int cmd, 38 struct page *raw_page, unsigned raw_off, 39 struct page *loop_page, unsigned loop_off, 40 int size, sector_t real_block); 41 char lo_file_name[LO_NAME_SIZE]; 42 char lo_crypt_name[LO_NAME_SIZE]; 43 char lo_encrypt_key[LO_KEY_SIZE]; 44 int lo_encrypt_key_size; 45 struct loop_func_table *lo_encryption; 46 __u32 lo_init[2]; 47 uid_t lo_key_owner; /* Who set the key */ 48 int (*ioctl)(struct loop_device *, int cmd, 49 unsigned long arg); 50 51 struct file * lo_backing_file; 52 struct block_device *lo_device; 53 unsigned lo_blocksize; 54 void *key_data; 55 56 gfp_t old_gfp_mask; 57 58 spinlock_t lo_lock; 59 struct bio *lo_bio; 60 struct bio *lo_biotail; 61 int lo_state; 62 struct completion lo_done; 63 struct completion lo_bh_done; 64 struct mutex lo_ctl_mutex; 65 int lo_pending; 66 67 request_queue_t *lo_queue; 68 }; 69 70 #endif /* __KERNEL__ */ 71 72 /* 73 * Loop flags 74 */ 75 enum { 76 LO_FLAGS_READ_ONLY = 1, 77 LO_FLAGS_USE_AOPS = 2, 78 }; 79 80 #include <asm/posix_types.h> /* for __kernel_old_dev_t */ 81 #include <asm/types.h> /* for __u64 */ 82 83 /* Backwards compatibility version */ 84 struct loop_info { 85 int lo_number; /* ioctl r/o */ 86 __kernel_old_dev_t lo_device; /* ioctl r/o */ 87 unsigned long lo_inode; /* ioctl r/o */ 88 __kernel_old_dev_t lo_rdevice; /* ioctl r/o */ 89 int lo_offset; 90 int lo_encrypt_type; 91 int lo_encrypt_key_size; /* ioctl w/o */ 92 int lo_flags; /* ioctl r/o */ 93 char lo_name[LO_NAME_SIZE]; 94 unsigned char lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */ 95 unsigned long lo_init[2]; 96 char reserved[4]; 97 }; 98 99 struct loop_info64 { 100 __u64 lo_device; /* ioctl r/o */ 101 __u64 lo_inode; /* ioctl r/o */ 102 __u64 lo_rdevice; /* ioctl r/o */ 103 __u64 lo_offset; 104 __u64 lo_sizelimit;/* bytes, 0 == max available */ 105 __u32 lo_number; /* ioctl r/o */ 106 __u32 lo_encrypt_type; 107 __u32 lo_encrypt_key_size; /* ioctl w/o */ 108 __u32 lo_flags; /* ioctl r/o */ 109 __u8 lo_file_name[LO_NAME_SIZE]; 110 __u8 lo_crypt_name[LO_NAME_SIZE]; 111 __u8 lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */ 112 __u64 lo_init[2]; 113 }; 114 115 /* 116 * Loop filter types 117 */ 118 119 #define LO_CRYPT_NONE 0 120 #define LO_CRYPT_XOR 1 121 #define LO_CRYPT_DES 2 122 #define LO_CRYPT_FISH2 3 /* Twofish encryption */ 123 #define LO_CRYPT_BLOW 4 124 #define LO_CRYPT_CAST128 5 125 #define LO_CRYPT_IDEA 6 126 #define LO_CRYPT_DUMMY 9 127 #define LO_CRYPT_SKIPJACK 10 128 #define LO_CRYPT_CRYPTOAPI 18 129 #define MAX_LO_CRYPT 20 130 131 #ifdef __KERNEL__ 132 /* Support for loadable transfer modules */ 133 struct loop_func_table { 134 int number; /* filter type */ 135 int (*transfer)(struct loop_device *lo, int cmd, 136 struct page *raw_page, unsigned raw_off, 137 struct page *loop_page, unsigned loop_off, 138 int size, sector_t real_block); 139 int (*init)(struct loop_device *, const struct loop_info64 *); 140 /* release is called from loop_unregister_transfer or clr_fd */ 141 int (*release)(struct loop_device *); 142 int (*ioctl)(struct loop_device *, int cmd, unsigned long arg); 143 struct module *owner; 144 }; 145 146 int loop_register_transfer(struct loop_func_table *funcs); 147 int loop_unregister_transfer(int number); 148 149 #endif 150 /* 151 * IOCTL commands --- we will commandeer 0x4C ('L') 152 */ 153 154 #define LOOP_SET_FD 0x4C00 155 #define LOOP_CLR_FD 0x4C01 156 #define LOOP_SET_STATUS 0x4C02 157 #define LOOP_GET_STATUS 0x4C03 158 #define LOOP_SET_STATUS64 0x4C04 159 #define LOOP_GET_STATUS64 0x4C05 160 #define LOOP_CHANGE_FD 0x4C06 161 162 #endif 163
