X-Git-Url: http://wagnertech.de/git?a=blobdiff_plain;f=i686-linux-gnu-4.7%2Fusr%2Finclude%2Flinux%2Fcramfs_fs.h;fp=i686-linux-gnu-4.7%2Fusr%2Finclude%2Flinux%2Fcramfs_fs.h;h=a4ce74e34bfc18e7580a6f3c78b32526f9499693;hb=94df942c2c7bd3457276fe5b7367623cbb8c1302;hp=0000000000000000000000000000000000000000;hpb=4dd7d9155a920895ff7b1cb6b9c9c676aa62000a;p=cross.git

diff --git a/i686-linux-gnu-4.7/usr/include/linux/cramfs_fs.h b/i686-linux-gnu-4.7/usr/include/linux/cramfs_fs.h
new file mode 100644
index 0000000..a4ce74e
--- /dev/null
+++ b/i686-linux-gnu-4.7/usr/include/linux/cramfs_fs.h
@@ -0,0 +1,113 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef __CRAMFS_H
+#define __CRAMFS_H
+
+#include <linux/types.h>
+#include <linux/magic.h>
+
+#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 */
+#define CRAMFS_FLAG_EXT_BLOCK_POINTERS	0x00000800	/* block pointer extensions */
+
+/*
+ * 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 \
+				| CRAMFS_FLAG_EXT_BLOCK_POINTERS )
+
+/*
+ * Block pointer flags
+ *
+ * The maximum block offset that needs to be represented is roughly:
+ *
+ *   (1 << CRAMFS_OFFSET_WIDTH) * 4 +
+ *   (1 << CRAMFS_SIZE_WIDTH) / PAGE_SIZE * (4 + PAGE_SIZE)
+ *   = 0x11004000
+ *
+ * That leaves room for 3 flag bits in the block pointer table.
+ */
+#define CRAMFS_BLK_FLAG_UNCOMPRESSED	(1 << 31)
+#define CRAMFS_BLK_FLAG_DIRECT_PTR	(1 << 30)
+
+#define CRAMFS_BLK_FLAGS	( CRAMFS_BLK_FLAG_UNCOMPRESSED \
+				| CRAMFS_BLK_FLAG_DIRECT_PTR )
+
+/*
+ * Direct blocks are at least 4-byte aligned.
+ * Pointers to direct blocks are shifted down by 2 bits.
+ */
+#define CRAMFS_BLK_DIRECT_PTR_SHIFT	2
+
+#endif /* __CRAMFS_H */