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git.ipfire.org Git - thirdparty/util-linux.git/blob - include/loopdev.h
2 * No copyright is claimed. This code is in the public domain; do with
5 #ifndef UTIL_LINUX_LOOPDEV_H
6 #define UTIL_LINUX_LOOPDEV_H
11 * loop_info.lo_encrypt_type
13 #define LO_CRYPT_NONE 0
14 #define LO_CRYPT_XOR 1
15 #define LO_CRYPT_DES 2
16 #define LO_CRYPT_CRYPTOAPI 18
18 #define LOOP_SET_FD 0x4C00
19 #define LOOP_CLR_FD 0x4C01
21 * Obsolete (kernel < 2.6)
23 * #define LOOP_SET_STATUS 0x4C02
24 * #define LOOP_GET_STATUS 0x4C03
26 #define LOOP_SET_STATUS64 0x4C04
27 #define LOOP_GET_STATUS64 0x4C05
28 /* #define LOOP_CHANGE_FD 0x4C06 */
29 #define LOOP_SET_CAPACITY 0x4C07
30 #define LOOP_SET_DIRECT_IO 0x4C08
31 #define LOOP_SET_BLOCK_SIZE 0x4C09
33 /* /dev/loop-control interface */
35 # define LOOP_CTL_ADD 0x4C80
36 # define LOOP_CTL_REMOVE 0x4C81
37 # define LOOP_CTL_GET_FREE 0x4C82
44 LO_FLAGS_READ_ONLY
= 1,
45 LO_FLAGS_USE_AOPS
= 2,
46 LO_FLAGS_AUTOCLEAR
= 4, /* kernel >= 2.6.25 */
47 LO_FLAGS_PARTSCAN
= 8, /* kernel >= 3.2 */
48 LO_FLAGS_DIRECT_IO
= 16, /* kernel >= 4.2 */
51 #define LO_NAME_SIZE 64
52 #define LO_KEY_SIZE 32
55 * Linux LOOP_{SET,GET}_STATUS64 ioctl struct
62 uint64_t lo_sizelimit
; /* bytes, 0 == max available */
64 uint32_t lo_encrypt_type
;
65 uint32_t lo_encrypt_key_size
;
67 uint8_t lo_file_name
[LO_NAME_SIZE
];
68 uint8_t lo_crypt_name
[LO_NAME_SIZE
];
69 uint8_t lo_encrypt_key
[LO_KEY_SIZE
];
73 #ifndef LOOP_CONFIGURE
75 * Since Linux v5.8-rc1 (commit 3448914e8cc550ba792d4ccc74471d1ca4293aae)
77 # define LOOP_CONFIGURE 0x4C0A
81 struct loop_info64 info
;
82 uint64_t __reserved
[8];
86 #define LOOPDEV_MAJOR 7 /* loop major number */
87 #define LOOPDEV_DEFAULT_NNODES 8 /* default number of loop devices */
90 FILE *proc
; /* /proc/partitions */
91 DIR *sysblock
; /* /sys/block */
92 int ncur
; /* current position */
93 int *minors
; /* ary of minor numbers (when scan whole /dev) */
94 int nminors
; /* number of items in *minors */
95 int ct_perm
; /* count permission problems */
96 int ct_succ
; /* count number of detected devices */
98 unsigned int done
:1; /* scanning done */
99 unsigned int default_check
:1;/* check first LOOPDEV_NLOOPS */
100 int flags
; /* LOOPITER_FL_* flags */
104 LOOPITER_FL_FREE
= (1 << 0),
105 LOOPITER_FL_USED
= (1 << 1)
109 * handler for work with loop devices
112 char device
[128]; /* device path (e.g. /dev/loop<N>) */
113 char *filename
; /* backing file for loopcxt_set_... */
114 int fd
; /* open(/dev/looo<N>) */
115 mode_t mode
; /* fd mode O_{RDONLY,RDWR} */
116 uint64_t blocksize
; /* used by loopcxt_setup_device() */
118 int flags
; /* LOOPDEV_FL_* flags */
119 unsigned int has_info
:1; /* .info contains data */
120 unsigned int extra_check
:1; /* unusual stuff for iterator */
121 unsigned int info_failed
:1; /* LOOP_GET_STATUS ioctl failed */
122 unsigned int control_ok
:1; /* /dev/loop-control success */
124 struct path_cxt
*sysfs
; /* pointer to /sys/dev/block/<maj:min>/ */
125 struct loop_config config
; /* for GET/SET ioctl */
126 struct loopdev_iter iter
; /* scans /sys or /dev for used/free devices */
129 #define UL_LOOPDEVCXT_EMPTY { .fd = -1 }
135 LOOPDEV_FL_OFFSET
= (1 << 4),
136 LOOPDEV_FL_NOSYSFS
= (1 << 5),
137 LOOPDEV_FL_NOIOCTL
= (1 << 6),
138 LOOPDEV_FL_DEVSUBDIR
= (1 << 7),
139 LOOPDEV_FL_CONTROL
= (1 << 8), /* system with /dev/loop-control */
140 LOOPDEV_FL_SIZELIMIT
= (1 << 9)
146 extern int loopmod_supports_partscan(void);
148 extern int is_loopdev(const char *device
);
149 extern int loopdev_is_autoclear(const char *device
);
151 extern char *loopdev_get_backing_file(const char *device
);
152 extern int loopdev_has_backing_file(const char *device
);
153 extern int loopdev_is_used(const char *device
, const char *filename
,
154 uint64_t offset
, uint64_t sizelimit
, int flags
);
155 extern char *loopdev_find_by_backing_file(const char *filename
,
156 uint64_t offset
, uint64_t sizelimit
, int flags
);
157 extern int loopcxt_find_unused(struct loopdev_cxt
*lc
);
158 extern int loopdev_delete(const char *device
);
159 extern int loopdev_count_by_backing_file(const char *filename
, char **loopdev
);
164 extern int loopcxt_init(struct loopdev_cxt
*lc
, int flags
)
165 __attribute__ ((warn_unused_result
));
166 extern void loopcxt_deinit(struct loopdev_cxt
*lc
);
168 extern int loopcxt_set_device(struct loopdev_cxt
*lc
, const char *device
)
169 __attribute__ ((warn_unused_result
));
170 extern int loopcxt_has_device(struct loopdev_cxt
*lc
);
171 extern int loopcxt_add_device(struct loopdev_cxt
*lc
);
172 extern char *loopcxt_strdup_device(struct loopdev_cxt
*lc
);
173 extern const char *loopcxt_get_device(struct loopdev_cxt
*lc
);
174 extern struct loop_info64
*loopcxt_get_info(struct loopdev_cxt
*lc
);
176 extern int loopcxt_get_fd(struct loopdev_cxt
*lc
);
177 extern int loopcxt_set_fd(struct loopdev_cxt
*lc
, int fd
, mode_t mode
);
179 extern int loopcxt_init_iterator(struct loopdev_cxt
*lc
, int flags
);
180 extern int loopcxt_deinit_iterator(struct loopdev_cxt
*lc
);
181 extern int loopcxt_next(struct loopdev_cxt
*lc
);
183 extern int loopcxt_setup_device(struct loopdev_cxt
*lc
);
184 extern int loopcxt_delete_device(struct loopdev_cxt
*lc
);
186 extern int loopcxt_ioctl_status(struct loopdev_cxt
*lc
);
187 extern int loopcxt_ioctl_capacity(struct loopdev_cxt
*lc
);
188 extern int loopcxt_ioctl_dio(struct loopdev_cxt
*lc
, unsigned long use_dio
);
189 extern int loopcxt_ioctl_blocksize(struct loopdev_cxt
*lc
, uint64_t blocksize
);
191 int loopcxt_set_offset(struct loopdev_cxt
*lc
, uint64_t offset
);
192 int loopcxt_set_sizelimit(struct loopdev_cxt
*lc
, uint64_t sizelimit
);
193 int loopcxt_set_blocksize(struct loopdev_cxt
*lc
, uint64_t blocksize
);
194 int loopcxt_set_flags(struct loopdev_cxt
*lc
, uint32_t flags
);
195 int loopcxt_set_backing_file(struct loopdev_cxt
*lc
, const char *filename
);
196 int loopcxt_set_refname(struct loopdev_cxt
*lc
, const char *refname
);
198 extern char *loopcxt_get_backing_file(struct loopdev_cxt
*lc
);
199 extern char *loopcxt_get_refname(struct loopdev_cxt
*lc
);
200 extern int loopcxt_get_backing_devno(struct loopdev_cxt
*lc
, dev_t
*devno
);
201 extern int loopcxt_get_backing_inode(struct loopdev_cxt
*lc
, ino_t
*ino
);
202 extern int loopcxt_get_offset(struct loopdev_cxt
*lc
, uint64_t *offset
);
203 extern int loopcxt_get_blocksize(struct loopdev_cxt
*lc
, uint64_t *blocksize
);
204 extern int loopcxt_get_sizelimit(struct loopdev_cxt
*lc
, uint64_t *size
);
205 extern int loopcxt_get_encrypt_type(struct loopdev_cxt
*lc
, uint32_t *type
);
206 extern const char *loopcxt_get_crypt_name(struct loopdev_cxt
*lc
);
207 extern int loopcxt_is_autoclear(struct loopdev_cxt
*lc
);
208 extern int loopcxt_is_readonly(struct loopdev_cxt
*lc
);
209 extern int loopcxt_is_dio(struct loopdev_cxt
*lc
);
210 extern int loopcxt_is_partscan(struct loopdev_cxt
*lc
);
211 extern int loopcxt_find_by_backing_file(struct loopdev_cxt
*lc
,
212 const char *filename
,
213 uint64_t offset
, uint64_t sizelimit
,
215 extern int loopcxt_find_overlap(struct loopdev_cxt
*lc
,
216 const char *filename
,
217 uint64_t offset
, uint64_t sizelimit
);
219 extern int loopcxt_is_used(struct loopdev_cxt
*lc
,
221 const char *backing_file
,
226 #endif /* UTIL_LINUX_LOOPDEV_H */