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gerrit-public.fairphone.software / kernel / msm / 333f981720d619e2038b980a55ad01b10580eb9f / . / include / linux / loop.h
blob: 8220d9c9da0073e2f2b35bd4fe4ce0b2c29e4332 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]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
21/* Possible states of device */
22enum {
23 Lo_unbound,
24 Lo_bound,
25 Lo_rundown,
26};
27
28struct loop_func_table;
29
30struct loop_device {
31 int lo_number;
32 int lo_refcnt;
33 loff_t lo_offset;
34 loff_t lo_sizelimit;
35 int lo_flags;
36 int (*transfer)(struct loop_device *, int cmd,
37 struct page *raw_page, unsigned raw_off,
38 struct page *loop_page, unsigned loop_off,
39 int size, sector_t real_block);
40 char lo_file_name[LO_NAME_SIZE];
41 char lo_crypt_name[LO_NAME_SIZE];
42 char lo_encrypt_key[LO_KEY_SIZE];
43 int lo_encrypt_key_size;
44 struct loop_func_table *lo_encryption;
45 __u32 lo_init[2];
46 uid_t lo_key_owner; /* Who set the key */
47 int (*ioctl)(struct loop_device *, int cmd,
48 unsigned long arg);
49
50 struct file * lo_backing_file;
51 struct block_device *lo_device;
52 unsigned lo_blocksize;
53 void *key_data;
54
55 int old_gfp_mask;
56
57 spinlock_t lo_lock;
58 struct bio *lo_bio;
59 struct bio *lo_biotail;
60 int lo_state;
61 struct semaphore lo_sem;
62 struct semaphore lo_ctl_mutex;
63 struct semaphore lo_bh_mutex;
64 atomic_t lo_pending;
65
66 request_queue_t *lo_queue;
67};
68
69#endif /* __KERNEL__ */
70
71/*
72 * Loop flags
73 */
74enum {
75 LO_FLAGS_READ_ONLY = 1,
76 LO_FLAGS_USE_AOPS = 2,
77};
78
79#include <asm/posix_types.h> /* for __kernel_old_dev_t */
80#include <asm/types.h> /* for __u64 */
81
82/* Backwards compatibility version */
83struct loop_info {
84 int lo_number; /* ioctl r/o */
85 __kernel_old_dev_t lo_device; /* ioctl r/o */
86 unsigned long lo_inode; /* ioctl r/o */
87 __kernel_old_dev_t lo_rdevice; /* ioctl r/o */
88 int lo_offset;
89 int lo_encrypt_type;
90 int lo_encrypt_key_size; /* ioctl w/o */
91 int lo_flags; /* ioctl r/o */
92 char lo_name[LO_NAME_SIZE];
93 unsigned char lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */
94 unsigned long lo_init[2];
95 char reserved[4];
96};
97
98struct loop_info64 {
99 __u64 lo_device; /* ioctl r/o */
100 __u64 lo_inode; /* ioctl r/o */
101 __u64 lo_rdevice; /* ioctl r/o */
102 __u64 lo_offset;
103 __u64 lo_sizelimit;/* bytes, 0 == max available */
104 __u32 lo_number; /* ioctl r/o */
105 __u32 lo_encrypt_type;
106 __u32 lo_encrypt_key_size; /* ioctl w/o */
107 __u32 lo_flags; /* ioctl r/o */
108 __u8 lo_file_name[LO_NAME_SIZE];
109 __u8 lo_crypt_name[LO_NAME_SIZE];
110 __u8 lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */
111 __u64 lo_init[2];
112};
113
114/*
115 * Loop filter types
116 */
117
118#define LO_CRYPT_NONE 0
119#define LO_CRYPT_XOR 1
120#define LO_CRYPT_DES 2
121#define LO_CRYPT_FISH2 3 /* Twofish encryption */
122#define LO_CRYPT_BLOW 4
123#define LO_CRYPT_CAST128 5
124#define LO_CRYPT_IDEA 6
125#define LO_CRYPT_DUMMY 9
126#define LO_CRYPT_SKIPJACK 10
127#define LO_CRYPT_CRYPTOAPI 18
128#define MAX_LO_CRYPT 20
129
130#ifdef __KERNEL__
131/* Support for loadable transfer modules */
132struct loop_func_table {
133 int number; /* filter type */
134 int (*transfer)(struct loop_device *lo, int cmd,
135 struct page *raw_page, unsigned raw_off,
136 struct page *loop_page, unsigned loop_off,
137 int size, sector_t real_block);
138 int (*init)(struct loop_device *, const struct loop_info64 *);
139 /* release is called from loop_unregister_transfer or clr_fd */
140 int (*release)(struct loop_device *);
141 int (*ioctl)(struct loop_device *, int cmd, unsigned long arg);
142 struct module *owner;
143};
144
145int loop_register_transfer(struct loop_func_table *funcs);
146int loop_unregister_transfer(int number);
147
148#endif
149/*
150 * IOCTL commands --- we will commandeer 0x4C ('L')
151 */
152
153#define LOOP_SET_FD 0x4C00
154#define LOOP_CLR_FD 0x4C01
155#define LOOP_SET_STATUS 0x4C02
156#define LOOP_GET_STATUS 0x4C03
157#define LOOP_SET_STATUS64 0x4C04
158#define LOOP_GET_STATUS64 0x4C05
159#define LOOP_CHANGE_FD 0x4C06
160
161#endif