| 1 |
13 |
serginhofr |
#ifndef __CRAMFS_H
|
| 2 |
|
|
#define __CRAMFS_H
|
| 3 |
|
|
|
| 4 |
|
|
#include <linux/types.h>
|
| 5 |
|
|
#include <linux/magic.h>
|
| 6 |
|
|
|
| 7 |
|
|
#define CRAMFS_SIGNATURE "Compressed ROMFS"
|
| 8 |
|
|
|
| 9 |
|
|
/*
|
| 10 |
|
|
* Width of various bitfields in struct cramfs_inode.
|
| 11 |
|
|
* Primarily used to generate warnings in mkcramfs.
|
| 12 |
|
|
*/
|
| 13 |
|
|
#define CRAMFS_MODE_WIDTH 16
|
| 14 |
|
|
#define CRAMFS_UID_WIDTH 16
|
| 15 |
|
|
#define CRAMFS_SIZE_WIDTH 24
|
| 16 |
|
|
#define CRAMFS_GID_WIDTH 8
|
| 17 |
|
|
#define CRAMFS_NAMELEN_WIDTH 6
|
| 18 |
|
|
#define CRAMFS_OFFSET_WIDTH 26
|
| 19 |
|
|
|
| 20 |
|
|
/*
|
| 21 |
|
|
* Since inode.namelen is a unsigned 6-bit number, the maximum cramfs
|
| 22 |
|
|
* path length is 63 << 2 = 252.
|
| 23 |
|
|
*/
|
| 24 |
|
|
#define CRAMFS_MAXPATHLEN (((1 << CRAMFS_NAMELEN_WIDTH) - 1) << 2)
|
| 25 |
|
|
|
| 26 |
|
|
/*
|
| 27 |
|
|
* Reasonably terse representation of the inode data.
|
| 28 |
|
|
*/
|
| 29 |
|
|
struct cramfs_inode {
|
| 30 |
|
|
__u32 mode:CRAMFS_MODE_WIDTH, uid:CRAMFS_UID_WIDTH;
|
| 31 |
|
|
/* SIZE for device files is i_rdev */
|
| 32 |
|
|
__u32 size:CRAMFS_SIZE_WIDTH, gid:CRAMFS_GID_WIDTH;
|
| 33 |
|
|
/* NAMELEN is the length of the file name, divided by 4 and
|
| 34 |
|
|
rounded up. (cramfs doesn't support hard links.) */
|
| 35 |
|
|
/* OFFSET: For symlinks and non-empty regular files, this
|
| 36 |
|
|
contains the offset (divided by 4) of the file data in
|
| 37 |
|
|
compressed form (starting with an array of block pointers;
|
| 38 |
|
|
see README). For non-empty directories it is the offset
|
| 39 |
|
|
(divided by 4) of the inode of the first file in that
|
| 40 |
|
|
directory. For anything else, offset is zero. */
|
| 41 |
|
|
__u32 namelen:CRAMFS_NAMELEN_WIDTH, offset:CRAMFS_OFFSET_WIDTH;
|
| 42 |
|
|
};
|
| 43 |
|
|
|
| 44 |
|
|
struct cramfs_info {
|
| 45 |
|
|
__u32 crc;
|
| 46 |
|
|
__u32 edition;
|
| 47 |
|
|
__u32 blocks;
|
| 48 |
|
|
__u32 files;
|
| 49 |
|
|
};
|
| 50 |
|
|
|
| 51 |
|
|
/*
|
| 52 |
|
|
* Superblock information at the beginning of the FS.
|
| 53 |
|
|
*/
|
| 54 |
|
|
struct cramfs_super {
|
| 55 |
|
|
__u32 magic; /* 0x28cd3d45 - random number */
|
| 56 |
|
|
__u32 size; /* length in bytes */
|
| 57 |
|
|
__u32 flags; /* feature flags */
|
| 58 |
|
|
__u32 future; /* reserved for future use */
|
| 59 |
|
|
__u8 signature[16]; /* "Compressed ROMFS" */
|
| 60 |
|
|
struct cramfs_info fsid; /* unique filesystem info */
|
| 61 |
|
|
__u8 name[16]; /* user-defined name */
|
| 62 |
|
|
struct cramfs_inode root; /* root inode data */
|
| 63 |
|
|
};
|
| 64 |
|
|
|
| 65 |
|
|
/*
|
| 66 |
|
|
* Feature flags
|
| 67 |
|
|
*
|
| 68 |
|
|
* 0x00000000 - 0x000000ff: features that work for all past kernels
|
| 69 |
|
|
* 0x00000100 - 0xffffffff: features that don't work for past kernels
|
| 70 |
|
|
*/
|
| 71 |
|
|
#define CRAMFS_FLAG_FSID_VERSION_2 0x00000001 /* fsid version #2 */
|
| 72 |
|
|
#define CRAMFS_FLAG_SORTED_DIRS 0x00000002 /* sorted dirs */
|
| 73 |
|
|
#define CRAMFS_FLAG_HOLES 0x00000100 /* support for holes */
|
| 74 |
|
|
#define CRAMFS_FLAG_WRONG_SIGNATURE 0x00000200 /* reserved */
|
| 75 |
|
|
#define CRAMFS_FLAG_SHIFTED_ROOT_OFFSET 0x00000400 /* shifted root fs */
|
| 76 |
|
|
|
| 77 |
|
|
/*
|
| 78 |
|
|
* Valid values in super.flags. Currently we refuse to mount
|
| 79 |
|
|
* if (flags & ~CRAMFS_SUPPORTED_FLAGS). Maybe that should be
|
| 80 |
|
|
* changed to test super.future instead.
|
| 81 |
|
|
*/
|
| 82 |
|
|
#define CRAMFS_SUPPORTED_FLAGS ( 0x000000ff \
|
| 83 |
|
|
| CRAMFS_FLAG_HOLES \
|
| 84 |
|
|
| CRAMFS_FLAG_WRONG_SIGNATURE \
|
| 85 |
|
|
| CRAMFS_FLAG_SHIFTED_ROOT_OFFSET )
|
| 86 |
|
|
|
| 87 |
|
|
|
| 88 |
|
|
#endif /* __CRAMFS_H */
|
