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/*
* Copyright (c) 2008, XenSource Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of XenSource Inc. nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
* OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _QCOW_H_
#define _QCOW_H_
#include "aes.h"
/**************************************************************/
/* QEMU COW block driver with compression and encryption support */
#define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb)
#define XEN_MAGIC (('X' << 24) | ('E' << 16) | ('N' << 8) | 0xfb)
#define QCOW_VERSION 1
#define QCOW_CRYPT_NONE 0x00
#define QCOW_CRYPT_AES 0x01
#define QCOW_OFLAG_COMPRESSED (1LL << 63)
#define SPARSE_FILE 0x01
#define EXTHDR_L1_BIG_ENDIAN 0x02
#ifndef O_BINARY
#define O_BINARY 0
#endif
#define ROUNDUP(l, s) \
({ \
(uint64_t)( \
(l + (s - 1)) - ((l + (s - 1)) % s)); \
})
typedef struct QCowHeader {
uint32_t magic;
uint32_t version;
uint64_t backing_file_offset;
uint32_t backing_file_size;
uint32_t mtime;
uint64_t size; /* in bytes */
uint8_t cluster_bits;
uint8_t l2_bits;
uint32_t crypt_method;
uint64_t l1_table_offset;
} QCowHeader;
/*Extended header for Xen enhancements*/
typedef struct QCowHeader_ext {
uint32_t xmagic;
uint32_t cksum;
uint32_t min_cluster_alloc;
uint32_t flags;
} QCowHeader_ext;
uint32_t gen_cksum(char *ptr, int len);
int get_filesize(char *filename, uint64_t *size, struct stat *st);
int qtruncate(int fd, off_t length, int sparse);
#define L2_CACHE_SIZE 16 /*Fixed allocation in Qemu*/
struct tdqcow_state {
int fd; /*Main Qcow file descriptor */
uint64_t fd_end; /*Store a local record of file length */
char *name; /*Record of the filename*/
uint32_t backing_file_size;
uint64_t backing_file_offset;
uint8_t extended; /*File contains extended header*/
int encrypted; /*File contents are encrypted or plain*/
int cluster_bits; /*Determines length of cluster as
*indicated by file hdr*/
int cluster_size; /*Length of cluster*/
int cluster_sectors; /*Number of sectors per cluster*/
int cluster_alloc; /*Blktap fix for allocating full
*extents*/
int min_cluster_alloc; /*Blktap historical extent alloc*/
int sparse; /*Indicates whether to preserve sparseness*/
int l2_bits; /*Size of L2 table entry*/
int l2_size; /*Full table size*/
int l1_size; /*L1 table size*/
uint64_t cluster_offset_mask;
uint64_t l1_table_offset; /*L1 table offset from beginning of
*file*/
uint64_t *l1_table; /*L1 table entries*/
uint64_t *l2_cache; /*We maintain a cache of size
*L2_CACHE_SIZE of most read entries*/
uint64_t l2_cache_offsets[L2_CACHE_SIZE]; /*L2 cache entries*/
uint32_t l2_cache_counts[L2_CACHE_SIZE]; /*Cache access record*/
uint8_t *cluster_cache;
uint8_t *cluster_data;
uint64_t cluster_cache_offset; /**/
uint32_t crypt_method; /*current crypt method, 0 if no
*key yet */
uint32_t crypt_method_header; /**/
AES_KEY aes_encrypt_key; /*AES key*/
AES_KEY aes_decrypt_key; /*AES key*/
/* libaio state */
int aio_free_count;
int max_aio_reqs;
struct qcow_request *aio_requests;
struct qcow_request **aio_free_list;
};
int qcow_create(const char *filename, uint64_t total_size,
const char *backing_file, int sparse);
#endif //_QCOW_H_
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