From 5dced3d1b3deca80e01415a2e35dc7972dcbfae7 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Fri, 19 Apr 2024 11:25:10 +0200 Subject: Adding upstream version 1.47.0. Signed-off-by: Daniel Baumann --- lib/ext2fs/qcow2.h | 114 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 114 insertions(+) create mode 100644 lib/ext2fs/qcow2.h (limited to 'lib/ext2fs/qcow2.h') diff --git a/lib/ext2fs/qcow2.h b/lib/ext2fs/qcow2.h new file mode 100644 index 0000000..b649c9c --- /dev/null +++ b/lib/ext2fs/qcow2.h @@ -0,0 +1,114 @@ +/* + * qcow2.h --- structures and function prototypes for qcow2.c to generate + * qcow2 formatted disk images. This format is used originally by QEMU + * for virtual machines, and stores the filesystem data on disk in a + * packed format to avoid creating sparse image files that need lots of + * seeking to read and write. + * + * The qcow2 format supports zlib compression, but that is not yet + * implemented. + * + * It is possible to directly mount a qcow2 image using qemu-nbd: + * + * [root]# modprobe nbd max_part=63 + * [root]# qemu-nbd -c /dev/nbd0 image.img + * [root]# mount /dev/nbd0p1 /mnt/qemu + * + * Format details at http://people.gnome.org/~markmc/qcow-image-format.html + * + * Copyright (C) 2010 Red Hat, Inc., Lukas Czerner + * + * %Begin-Header% + * This file may be redistributed under the terms of the GNU Public + * License. + * %End-Header% + */ + +/* Number of l2 tables in memory before writeback */ +#define L2_CACHE_PREALLOC 512 + + +#define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb) +#define QCOW_VERSION 2 +#define QCOW_OFLAG_COPIED (1ULL << 63) +#define QCOW_OFLAG_COMPRESSED (1ULL << 62) + +#define QCOW_COMPRESSED 1 +#define QCOW_ENCRYPTED 2 +#define QCOW_CORRUPTED 3 + +struct ext2_qcow2_hdr { + __u32 magic; + __u32 version; + + __u64 backing_file_offset; + __u32 backing_file_size; + + __u32 cluster_bits; + __u64 size; + __u32 crypt_method; + + __u32 l1_size; + __u64 l1_table_offset; + + __u64 refcount_table_offset; + __u32 refcount_table_clusters; + + __u32 nb_snapshots; + __u64 snapshots_offset; +}; + +typedef struct ext2_qcow2_l2_table L2_CACHE_HEAD; + +struct ext2_qcow2_l2_table { + __u32 l1_index; + __u64 offset; + __u64 *data; + L2_CACHE_HEAD *next; +}; + +struct ext2_qcow2_l2_cache { + L2_CACHE_HEAD *used_head; + L2_CACHE_HEAD *used_tail; + L2_CACHE_HEAD *free_head; + __u32 free; + __u32 count; + __u64 next_offset; +}; + +struct ext2_qcow2_refcount { + __u64 *refcount_table; + __u64 refcount_table_offset; + __u64 refcount_block_offset; + + __u32 refcount_table_clusters; + __u32 refcount_table_index; + __u32 refcount_block_index; + + __u16 *refcount_block; +}; + +struct ext2_qcow2_image { + int fd; + struct ext2_qcow2_hdr *hdr; + struct ext2_qcow2_l2_cache *l2_cache; + struct ext2_qcow2_refcount refcount; + __u32 cluster_size; + __u32 cluster_bits; + __u32 l1_size; + __u32 l2_size; + + __u64 *l1_table; + __u64 l2_offset; + __u64 l1_offset; + __u64 image_size; +}; + +/* Function prototypes */ + +/* qcow2.c */ + +/* Functions for converting qcow2 image into raw image */ +struct ext2_qcow2_hdr *qcow2_read_header(int); +int qcow2_write_raw_image(int, int, struct ext2_qcow2_hdr *); + -- cgit v1.2.3