diff options
Diffstat (limited to 'include/cramfs')
| -rw-r--r-- | include/cramfs/cramfs_fs.h | 98 | ||||
| -rw-r--r-- | include/cramfs/cramfs_fs_sb.h | 19 |
2 files changed, 117 insertions, 0 deletions
diff --git a/include/cramfs/cramfs_fs.h b/include/cramfs/cramfs_fs.h new file mode 100644 index 0000000..7b292c0 --- /dev/null +++ b/include/cramfs/cramfs_fs.h @@ -0,0 +1,98 @@ +#ifndef __CRAMFS_H +#define __CRAMFS_H + +#ifndef __KERNEL__ + +typedef unsigned char u8; +typedef unsigned short u16; +typedef unsigned int u32; + +#endif + +#define CRAMFS_MAGIC 0x28cd3d45 /* some random number */ +#define CRAMFS_SIGNATURE "Compressed ROMFS" + +/* + * Width of various bitfields in struct cramfs_inode. + * Primarily used to generate warnings in mkcramfs. + */ +#define CRAMFS_MODE_WIDTH 16 +#define CRAMFS_UID_WIDTH 16 +#define CRAMFS_SIZE_WIDTH 24 +#define CRAMFS_GID_WIDTH 8 +#define CRAMFS_NAMELEN_WIDTH 6 +#define CRAMFS_OFFSET_WIDTH 26 + +/* + * Since inode.namelen is a unsigned 6-bit number, the maximum cramfs + * path length is 63 << 2 = 252. + */ +#define CRAMFS_MAXPATHLEN (((1 << CRAMFS_NAMELEN_WIDTH) - 1) << 2) + +/* + * Reasonably terse representation of the inode data. + */ +struct cramfs_inode { + u32 mode:CRAMFS_MODE_WIDTH, uid:CRAMFS_UID_WIDTH; + /* SIZE for device files is i_rdev */ + u32 size:CRAMFS_SIZE_WIDTH, gid:CRAMFS_GID_WIDTH; + /* NAMELEN is the length of the file name, divided by 4 and + rounded up. (cramfs doesn't support hard links.) */ + /* OFFSET: For symlinks and non-empty regular files, this + contains the offset (divided by 4) of the file data in + compressed form (starting with an array of block pointers; + see README). For non-empty directories it is the offset + (divided by 4) of the inode of the first file in that + directory. For anything else, offset is zero. */ + u32 namelen:CRAMFS_NAMELEN_WIDTH, offset:CRAMFS_OFFSET_WIDTH; +}; + +struct cramfs_info { + u32 crc; + u32 edition; + u32 blocks; + u32 files; +}; + +/* + * Superblock information at the beginning of the FS. + */ +struct cramfs_super { + u32 magic; /* 0x28cd3d45 - random number */ + u32 size; /* length in bytes */ + u32 flags; /* feature flags */ + u32 future; /* reserved for future use */ + u8 signature[16]; /* "Compressed ROMFS" */ + struct cramfs_info fsid; /* unique filesystem info */ + u8 name[16]; /* user-defined name */ + struct cramfs_inode root; /* root inode data */ +}; + +/* + * Feature flags + * + * 0x00000000 - 0x000000ff: features that work for all past kernels + * 0x00000100 - 0xffffffff: features that don't work for past kernels + */ +#define CRAMFS_FLAG_FSID_VERSION_2 0x00000001 /* fsid version #2 */ +#define CRAMFS_FLAG_SORTED_DIRS 0x00000002 /* sorted dirs */ +#define CRAMFS_FLAG_HOLES 0x00000100 /* support for holes */ +#define CRAMFS_FLAG_WRONG_SIGNATURE 0x00000200 /* reserved */ +#define CRAMFS_FLAG_SHIFTED_ROOT_OFFSET 0x00000400 /* shifted root fs */ + +/* + * Valid values in super.flags. Currently we refuse to mount + * if (flags & ~CRAMFS_SUPPORTED_FLAGS). Maybe that should be + * changed to test super.future instead. + */ +#define CRAMFS_SUPPORTED_FLAGS ( 0x000000ff \ + | CRAMFS_FLAG_HOLES \ + | CRAMFS_FLAG_WRONG_SIGNATURE \ + | CRAMFS_FLAG_SHIFTED_ROOT_OFFSET ) + +/* Uncompression interfaces to the underlying zlib */ +int cramfs_uncompress_block(void *dst, int dstlen, void *src, int srclen); +int cramfs_uncompress_init(void); +int cramfs_uncompress_exit(void); + +#endif diff --git a/include/cramfs/cramfs_fs_sb.h b/include/cramfs/cramfs_fs_sb.h new file mode 100644 index 0000000..bc23f94 --- /dev/null +++ b/include/cramfs/cramfs_fs_sb.h @@ -0,0 +1,19 @@ +#ifndef _CRAMFS_FS_SB +#define _CRAMFS_FS_SB + +/* + * cramfs super-block data in memory + */ +struct cramfs_sb_info { + unsigned long magic; + unsigned long size; + unsigned long blocks; + unsigned long files; + unsigned long flags; +#ifdef CONFIG_CRAMFS_LINEAR + unsigned long linear_phys_addr; + char * linear_virt_addr; +#endif +}; + +#endif |