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/*
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* Block driver for the QCOW version 2 format
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*
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* Copyright (c) 2004-2006 Fabrice Bellard
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "qemu-common.h" |
25 |
#include "block_int.h" |
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#include <zlib.h> |
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#include "aes.h" |
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#include <assert.h> |
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|
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/*
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Differences with QCOW:
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- Support for multiple incremental snapshots.
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- Memory management by reference counts.
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- Clusters which have a reference count of one have the bit
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QCOW_OFLAG_COPIED to optimize write performance.
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- Size of compressed clusters is stored in sectors to reduce bit usage
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in the cluster offsets.
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- Support for storing additional data (such as the VM state) in the
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snapshots.
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- If a backing store is used, the cluster size is not constrained
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(could be backported to QCOW).
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- L2 tables have always a size of one cluster.
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*/
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|
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//#define DEBUG_ALLOC
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//#define DEBUG_ALLOC2
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#define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb) |
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#define QCOW_VERSION 2 |
51 |
|
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#define QCOW_CRYPT_NONE 0 |
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#define QCOW_CRYPT_AES 1 |
54 |
|
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/* indicate that the refcount of the referenced cluster is exactly one. */
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#define QCOW_OFLAG_COPIED (1LL << 63) |
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/* indicate that the cluster is compressed (they never have the copied flag) */
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#define QCOW_OFLAG_COMPRESSED (1LL << 62) |
59 |
|
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#define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */ |
61 |
|
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#ifndef offsetof
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#define offsetof(type, field) ((size_t) &((type *)0)->field) |
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#endif
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|
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typedef struct QCowHeader { |
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uint32_t magic; |
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uint32_t version; |
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uint64_t backing_file_offset; |
70 |
uint32_t backing_file_size; |
71 |
uint32_t cluster_bits; |
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uint64_t size; /* in bytes */
|
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uint32_t crypt_method; |
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uint32_t l1_size; /* XXX: save number of clusters instead ? */
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uint64_t l1_table_offset; |
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uint64_t refcount_table_offset; |
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uint32_t refcount_table_clusters; |
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uint32_t nb_snapshots; |
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uint64_t snapshots_offset; |
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} QCowHeader; |
81 |
|
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typedef struct __attribute__((packed)) QCowSnapshotHeader { |
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/* header is 8 byte aligned */
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uint64_t l1_table_offset; |
85 |
|
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uint32_t l1_size; |
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uint16_t id_str_size; |
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uint16_t name_size; |
89 |
|
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uint32_t date_sec; |
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uint32_t date_nsec; |
92 |
|
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uint64_t vm_clock_nsec; |
94 |
|
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uint32_t vm_state_size; |
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uint32_t extra_data_size; /* for extension */
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/* extra data follows */
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/* id_str follows */
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/* name follows */
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} QCowSnapshotHeader; |
101 |
|
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#define L2_CACHE_SIZE 16 |
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|
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typedef struct QCowSnapshot { |
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uint64_t l1_table_offset; |
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uint32_t l1_size; |
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char *id_str;
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char *name;
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uint32_t vm_state_size; |
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uint32_t date_sec; |
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uint32_t date_nsec; |
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uint64_t vm_clock_nsec; |
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} QCowSnapshot; |
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|
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typedef struct BDRVQcowState { |
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BlockDriverState *hd; |
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int cluster_bits;
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int cluster_size;
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int cluster_sectors;
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int l2_bits;
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int l2_size;
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int l1_size;
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int l1_vm_state_index;
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int csize_shift;
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int csize_mask;
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uint64_t cluster_offset_mask; |
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uint64_t l1_table_offset; |
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uint64_t *l1_table; |
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uint64_t *l2_cache; |
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uint64_t l2_cache_offsets[L2_CACHE_SIZE]; |
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uint32_t l2_cache_counts[L2_CACHE_SIZE]; |
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uint8_t *cluster_cache; |
133 |
uint8_t *cluster_data; |
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uint64_t cluster_cache_offset; |
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|
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uint64_t *refcount_table; |
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uint64_t refcount_table_offset; |
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uint32_t refcount_table_size; |
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uint64_t refcount_block_cache_offset; |
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uint16_t *refcount_block_cache; |
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int64_t free_cluster_index; |
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int64_t free_byte_offset; |
143 |
|
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uint32_t crypt_method; /* current crypt method, 0 if no key yet */
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uint32_t crypt_method_header; |
146 |
AES_KEY aes_encrypt_key; |
147 |
AES_KEY aes_decrypt_key; |
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uint64_t snapshots_offset; |
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int snapshots_size;
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int nb_snapshots;
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QCowSnapshot *snapshots; |
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} BDRVQcowState; |
153 |
|
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static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset); |
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static int qcow_read(BlockDriverState *bs, int64_t sector_num, |
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uint8_t *buf, int nb_sectors);
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static int qcow_read_snapshots(BlockDriverState *bs); |
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static void qcow_free_snapshots(BlockDriverState *bs); |
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static int refcount_init(BlockDriverState *bs); |
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static void refcount_close(BlockDriverState *bs); |
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static int get_refcount(BlockDriverState *bs, int64_t cluster_index); |
162 |
static int update_cluster_refcount(BlockDriverState *bs, |
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int64_t cluster_index, |
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int addend);
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static void update_refcount(BlockDriverState *bs, |
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int64_t offset, int64_t length, |
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int addend);
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static int64_t alloc_clusters(BlockDriverState *bs, int64_t size);
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static int64_t alloc_bytes(BlockDriverState *bs, int size); |
170 |
static void free_clusters(BlockDriverState *bs, |
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int64_t offset, int64_t size); |
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#ifdef DEBUG_ALLOC
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static void check_refcounts(BlockDriverState *bs); |
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#endif
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static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename) |
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{ |
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const QCowHeader *cow_header = (const void *)buf; |
179 |
|
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if (buf_size >= sizeof(QCowHeader) && |
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be32_to_cpu(cow_header->magic) == QCOW_MAGIC && |
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be32_to_cpu(cow_header->version) == QCOW_VERSION) |
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return 100; |
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else
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return 0; |
186 |
} |
187 |
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static int qcow_open(BlockDriverState *bs, const char *filename, int flags) |
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{ |
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BDRVQcowState *s = bs->opaque; |
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int len, i, shift, ret;
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QCowHeader header; |
193 |
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ret = bdrv_file_open(&s->hd, filename, flags); |
195 |
if (ret < 0) |
196 |
return ret;
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if (bdrv_pread(s->hd, 0, &header, sizeof(header)) != sizeof(header)) |
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goto fail;
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be32_to_cpus(&header.magic); |
200 |
be32_to_cpus(&header.version); |
201 |
be64_to_cpus(&header.backing_file_offset); |
202 |
be32_to_cpus(&header.backing_file_size); |
203 |
be64_to_cpus(&header.size); |
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be32_to_cpus(&header.cluster_bits); |
205 |
be32_to_cpus(&header.crypt_method); |
206 |
be64_to_cpus(&header.l1_table_offset); |
207 |
be32_to_cpus(&header.l1_size); |
208 |
be64_to_cpus(&header.refcount_table_offset); |
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be32_to_cpus(&header.refcount_table_clusters); |
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be64_to_cpus(&header.snapshots_offset); |
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be32_to_cpus(&header.nb_snapshots); |
212 |
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if (header.magic != QCOW_MAGIC || header.version != QCOW_VERSION)
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goto fail;
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if (header.size <= 1 || |
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header.cluster_bits < 9 ||
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header.cluster_bits > 16)
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goto fail;
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if (header.crypt_method > QCOW_CRYPT_AES)
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goto fail;
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s->crypt_method_header = header.crypt_method; |
222 |
if (s->crypt_method_header)
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bs->encrypted = 1;
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s->cluster_bits = header.cluster_bits; |
225 |
s->cluster_size = 1 << s->cluster_bits;
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s->cluster_sectors = 1 << (s->cluster_bits - 9); |
227 |
s->l2_bits = s->cluster_bits - 3; /* L2 is always one cluster */ |
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s->l2_size = 1 << s->l2_bits;
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bs->total_sectors = header.size / 512;
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s->csize_shift = (62 - (s->cluster_bits - 8)); |
231 |
s->csize_mask = (1 << (s->cluster_bits - 8)) - 1; |
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s->cluster_offset_mask = (1LL << s->csize_shift) - 1; |
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s->refcount_table_offset = header.refcount_table_offset; |
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s->refcount_table_size = |
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header.refcount_table_clusters << (s->cluster_bits - 3);
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|
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s->snapshots_offset = header.snapshots_offset; |
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s->nb_snapshots = header.nb_snapshots; |
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|
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/* read the level 1 table */
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s->l1_size = header.l1_size; |
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shift = s->cluster_bits + s->l2_bits; |
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s->l1_vm_state_index = (header.size + (1LL << shift) - 1) >> shift; |
244 |
/* the L1 table must contain at least enough entries to put
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header.size bytes */
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if (s->l1_size < s->l1_vm_state_index)
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goto fail;
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s->l1_table_offset = header.l1_table_offset; |
249 |
s->l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t));
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if (!s->l1_table)
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goto fail;
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if (bdrv_pread(s->hd, s->l1_table_offset, s->l1_table, s->l1_size * sizeof(uint64_t)) != |
253 |
s->l1_size * sizeof(uint64_t))
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goto fail;
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for(i = 0;i < s->l1_size; i++) { |
256 |
be64_to_cpus(&s->l1_table[i]); |
257 |
} |
258 |
/* alloc L2 cache */
|
259 |
s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t));
|
260 |
if (!s->l2_cache)
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goto fail;
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262 |
s->cluster_cache = qemu_malloc(s->cluster_size); |
263 |
if (!s->cluster_cache)
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264 |
goto fail;
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265 |
/* one more sector for decompressed data alignment */
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266 |
s->cluster_data = qemu_malloc(s->cluster_size + 512);
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267 |
if (!s->cluster_data)
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268 |
goto fail;
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269 |
s->cluster_cache_offset = -1;
|
270 |
|
271 |
if (refcount_init(bs) < 0) |
272 |
goto fail;
|
273 |
|
274 |
/* read the backing file name */
|
275 |
if (header.backing_file_offset != 0) { |
276 |
len = header.backing_file_size; |
277 |
if (len > 1023) |
278 |
len = 1023;
|
279 |
if (bdrv_pread(s->hd, header.backing_file_offset, bs->backing_file, len) != len)
|
280 |
goto fail;
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281 |
bs->backing_file[len] = '\0';
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282 |
} |
283 |
if (qcow_read_snapshots(bs) < 0) |
284 |
goto fail;
|
285 |
|
286 |
#ifdef DEBUG_ALLOC
|
287 |
check_refcounts(bs); |
288 |
#endif
|
289 |
return 0; |
290 |
|
291 |
fail:
|
292 |
qcow_free_snapshots(bs); |
293 |
refcount_close(bs); |
294 |
qemu_free(s->l1_table); |
295 |
qemu_free(s->l2_cache); |
296 |
qemu_free(s->cluster_cache); |
297 |
qemu_free(s->cluster_data); |
298 |
bdrv_delete(s->hd); |
299 |
return -1; |
300 |
} |
301 |
|
302 |
static int qcow_set_key(BlockDriverState *bs, const char *key) |
303 |
{ |
304 |
BDRVQcowState *s = bs->opaque; |
305 |
uint8_t keybuf[16];
|
306 |
int len, i;
|
307 |
|
308 |
memset(keybuf, 0, 16); |
309 |
len = strlen(key); |
310 |
if (len > 16) |
311 |
len = 16;
|
312 |
/* XXX: we could compress the chars to 7 bits to increase
|
313 |
entropy */
|
314 |
for(i = 0;i < len;i++) { |
315 |
keybuf[i] = key[i]; |
316 |
} |
317 |
s->crypt_method = s->crypt_method_header; |
318 |
|
319 |
if (AES_set_encrypt_key(keybuf, 128, &s->aes_encrypt_key) != 0) |
320 |
return -1; |
321 |
if (AES_set_decrypt_key(keybuf, 128, &s->aes_decrypt_key) != 0) |
322 |
return -1; |
323 |
#if 0
|
324 |
/* test */
|
325 |
{
|
326 |
uint8_t in[16];
|
327 |
uint8_t out[16];
|
328 |
uint8_t tmp[16];
|
329 |
for(i=0;i<16;i++)
|
330 |
in[i] = i;
|
331 |
AES_encrypt(in, tmp, &s->aes_encrypt_key);
|
332 |
AES_decrypt(tmp, out, &s->aes_decrypt_key);
|
333 |
for(i = 0; i < 16; i++)
|
334 |
printf(" %02x", tmp[i]);
|
335 |
printf("\n");
|
336 |
for(i = 0; i < 16; i++)
|
337 |
printf(" %02x", out[i]);
|
338 |
printf("\n");
|
339 |
}
|
340 |
#endif
|
341 |
return 0; |
342 |
} |
343 |
|
344 |
/* The crypt function is compatible with the linux cryptoloop
|
345 |
algorithm for < 4 GB images. NOTE: out_buf == in_buf is
|
346 |
supported */
|
347 |
static void encrypt_sectors(BDRVQcowState *s, int64_t sector_num, |
348 |
uint8_t *out_buf, const uint8_t *in_buf,
|
349 |
int nb_sectors, int enc, |
350 |
const AES_KEY *key)
|
351 |
{ |
352 |
union {
|
353 |
uint64_t ll[2];
|
354 |
uint8_t b[16];
|
355 |
} ivec; |
356 |
int i;
|
357 |
|
358 |
for(i = 0; i < nb_sectors; i++) { |
359 |
ivec.ll[0] = cpu_to_le64(sector_num);
|
360 |
ivec.ll[1] = 0; |
361 |
AES_cbc_encrypt(in_buf, out_buf, 512, key,
|
362 |
ivec.b, enc); |
363 |
sector_num++; |
364 |
in_buf += 512;
|
365 |
out_buf += 512;
|
366 |
} |
367 |
} |
368 |
|
369 |
static int copy_sectors(BlockDriverState *bs, uint64_t start_sect, |
370 |
uint64_t cluster_offset, int n_start, int n_end) |
371 |
{ |
372 |
BDRVQcowState *s = bs->opaque; |
373 |
int n, ret;
|
374 |
|
375 |
n = n_end - n_start; |
376 |
if (n <= 0) |
377 |
return 0; |
378 |
ret = qcow_read(bs, start_sect + n_start, s->cluster_data, n); |
379 |
if (ret < 0) |
380 |
return ret;
|
381 |
if (s->crypt_method) {
|
382 |
encrypt_sectors(s, start_sect + n_start, |
383 |
s->cluster_data, |
384 |
s->cluster_data, n, 1,
|
385 |
&s->aes_encrypt_key); |
386 |
} |
387 |
ret = bdrv_write(s->hd, (cluster_offset >> 9) + n_start,
|
388 |
s->cluster_data, n); |
389 |
if (ret < 0) |
390 |
return ret;
|
391 |
return 0; |
392 |
} |
393 |
|
394 |
static void l2_cache_reset(BlockDriverState *bs) |
395 |
{ |
396 |
BDRVQcowState *s = bs->opaque; |
397 |
|
398 |
memset(s->l2_cache, 0, s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t)); |
399 |
memset(s->l2_cache_offsets, 0, L2_CACHE_SIZE * sizeof(uint64_t)); |
400 |
memset(s->l2_cache_counts, 0, L2_CACHE_SIZE * sizeof(uint32_t)); |
401 |
} |
402 |
|
403 |
static inline int l2_cache_new_entry(BlockDriverState *bs) |
404 |
{ |
405 |
BDRVQcowState *s = bs->opaque; |
406 |
uint32_t min_count; |
407 |
int min_index, i;
|
408 |
|
409 |
/* find a new entry in the least used one */
|
410 |
min_index = 0;
|
411 |
min_count = 0xffffffff;
|
412 |
for(i = 0; i < L2_CACHE_SIZE; i++) { |
413 |
if (s->l2_cache_counts[i] < min_count) {
|
414 |
min_count = s->l2_cache_counts[i]; |
415 |
min_index = i; |
416 |
} |
417 |
} |
418 |
return min_index;
|
419 |
} |
420 |
|
421 |
static int64_t align_offset(int64_t offset, int n) |
422 |
{ |
423 |
offset = (offset + n - 1) & ~(n - 1); |
424 |
return offset;
|
425 |
} |
426 |
|
427 |
static int grow_l1_table(BlockDriverState *bs, int min_size) |
428 |
{ |
429 |
BDRVQcowState *s = bs->opaque; |
430 |
int new_l1_size, new_l1_size2, ret, i;
|
431 |
uint64_t *new_l1_table; |
432 |
uint64_t new_l1_table_offset; |
433 |
uint64_t data64; |
434 |
uint32_t data32; |
435 |
|
436 |
new_l1_size = s->l1_size; |
437 |
if (min_size <= new_l1_size)
|
438 |
return 0; |
439 |
while (min_size > new_l1_size) {
|
440 |
new_l1_size = (new_l1_size * 3 + 1) / 2; |
441 |
} |
442 |
#ifdef DEBUG_ALLOC2
|
443 |
printf("grow l1_table from %d to %d\n", s->l1_size, new_l1_size);
|
444 |
#endif
|
445 |
|
446 |
new_l1_size2 = sizeof(uint64_t) * new_l1_size;
|
447 |
new_l1_table = qemu_mallocz(new_l1_size2); |
448 |
if (!new_l1_table)
|
449 |
return -ENOMEM;
|
450 |
memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t));
|
451 |
|
452 |
/* write new table (align to cluster) */
|
453 |
new_l1_table_offset = alloc_clusters(bs, new_l1_size2); |
454 |
|
455 |
for(i = 0; i < s->l1_size; i++) |
456 |
new_l1_table[i] = cpu_to_be64(new_l1_table[i]); |
457 |
ret = bdrv_pwrite(s->hd, new_l1_table_offset, new_l1_table, new_l1_size2); |
458 |
if (ret != new_l1_size2)
|
459 |
goto fail;
|
460 |
for(i = 0; i < s->l1_size; i++) |
461 |
new_l1_table[i] = be64_to_cpu(new_l1_table[i]); |
462 |
|
463 |
/* set new table */
|
464 |
data64 = cpu_to_be64(new_l1_table_offset); |
465 |
if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_table_offset),
|
466 |
&data64, sizeof(data64)) != sizeof(data64)) |
467 |
goto fail;
|
468 |
data32 = cpu_to_be32(new_l1_size); |
469 |
if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_size),
|
470 |
&data32, sizeof(data32)) != sizeof(data32)) |
471 |
goto fail;
|
472 |
qemu_free(s->l1_table); |
473 |
free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t));
|
474 |
s->l1_table_offset = new_l1_table_offset; |
475 |
s->l1_table = new_l1_table; |
476 |
s->l1_size = new_l1_size; |
477 |
return 0; |
478 |
fail:
|
479 |
qemu_free(s->l1_table); |
480 |
return -EIO;
|
481 |
} |
482 |
|
483 |
/* 'allocate' is:
|
484 |
*
|
485 |
* 0 not to allocate.
|
486 |
*
|
487 |
* 1 to allocate a normal cluster (for sector indexes 'n_start' to
|
488 |
* 'n_end')
|
489 |
*
|
490 |
* 2 to allocate a compressed cluster of size
|
491 |
* 'compressed_size'. 'compressed_size' must be > 0 and <
|
492 |
* cluster_size
|
493 |
*
|
494 |
* return 0 if not allocated.
|
495 |
*/
|
496 |
static uint64_t get_cluster_offset(BlockDriverState *bs,
|
497 |
uint64_t offset, int allocate,
|
498 |
int compressed_size,
|
499 |
int n_start, int n_end) |
500 |
{ |
501 |
BDRVQcowState *s = bs->opaque; |
502 |
int min_index, i, j, l1_index, l2_index, ret;
|
503 |
uint64_t l2_offset, *l2_table, cluster_offset, tmp, old_l2_offset; |
504 |
|
505 |
l1_index = offset >> (s->l2_bits + s->cluster_bits); |
506 |
if (l1_index >= s->l1_size) {
|
507 |
/* outside l1 table is allowed: we grow the table if needed */
|
508 |
if (!allocate)
|
509 |
return 0; |
510 |
if (grow_l1_table(bs, l1_index + 1) < 0) |
511 |
return 0; |
512 |
} |
513 |
l2_offset = s->l1_table[l1_index]; |
514 |
if (!l2_offset) {
|
515 |
if (!allocate)
|
516 |
return 0; |
517 |
l2_allocate:
|
518 |
old_l2_offset = l2_offset; |
519 |
/* allocate a new l2 entry */
|
520 |
l2_offset = alloc_clusters(bs, s->l2_size * sizeof(uint64_t));
|
521 |
/* update the L1 entry */
|
522 |
s->l1_table[l1_index] = l2_offset | QCOW_OFLAG_COPIED; |
523 |
tmp = cpu_to_be64(l2_offset | QCOW_OFLAG_COPIED); |
524 |
if (bdrv_pwrite(s->hd, s->l1_table_offset + l1_index * sizeof(tmp), |
525 |
&tmp, sizeof(tmp)) != sizeof(tmp)) |
526 |
return 0; |
527 |
min_index = l2_cache_new_entry(bs); |
528 |
l2_table = s->l2_cache + (min_index << s->l2_bits); |
529 |
|
530 |
if (old_l2_offset == 0) { |
531 |
memset(l2_table, 0, s->l2_size * sizeof(uint64_t)); |
532 |
} else {
|
533 |
if (bdrv_pread(s->hd, old_l2_offset,
|
534 |
l2_table, s->l2_size * sizeof(uint64_t)) !=
|
535 |
s->l2_size * sizeof(uint64_t))
|
536 |
return 0; |
537 |
} |
538 |
if (bdrv_pwrite(s->hd, l2_offset,
|
539 |
l2_table, s->l2_size * sizeof(uint64_t)) !=
|
540 |
s->l2_size * sizeof(uint64_t))
|
541 |
return 0; |
542 |
} else {
|
543 |
if (!(l2_offset & QCOW_OFLAG_COPIED)) {
|
544 |
if (allocate) {
|
545 |
free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t));
|
546 |
goto l2_allocate;
|
547 |
} |
548 |
} else {
|
549 |
l2_offset &= ~QCOW_OFLAG_COPIED; |
550 |
} |
551 |
for(i = 0; i < L2_CACHE_SIZE; i++) { |
552 |
if (l2_offset == s->l2_cache_offsets[i]) {
|
553 |
/* increment the hit count */
|
554 |
if (++s->l2_cache_counts[i] == 0xffffffff) { |
555 |
for(j = 0; j < L2_CACHE_SIZE; j++) { |
556 |
s->l2_cache_counts[j] >>= 1;
|
557 |
} |
558 |
} |
559 |
l2_table = s->l2_cache + (i << s->l2_bits); |
560 |
goto found;
|
561 |
} |
562 |
} |
563 |
/* not found: load a new entry in the least used one */
|
564 |
min_index = l2_cache_new_entry(bs); |
565 |
l2_table = s->l2_cache + (min_index << s->l2_bits); |
566 |
if (bdrv_pread(s->hd, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) != |
567 |
s->l2_size * sizeof(uint64_t))
|
568 |
return 0; |
569 |
} |
570 |
s->l2_cache_offsets[min_index] = l2_offset; |
571 |
s->l2_cache_counts[min_index] = 1;
|
572 |
found:
|
573 |
l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
|
574 |
cluster_offset = be64_to_cpu(l2_table[l2_index]); |
575 |
if (!cluster_offset) {
|
576 |
if (!allocate)
|
577 |
return cluster_offset;
|
578 |
} else if (!(cluster_offset & QCOW_OFLAG_COPIED)) { |
579 |
if (!allocate)
|
580 |
return cluster_offset;
|
581 |
/* free the cluster */
|
582 |
if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
|
583 |
int nb_csectors;
|
584 |
nb_csectors = ((cluster_offset >> s->csize_shift) & |
585 |
s->csize_mask) + 1;
|
586 |
free_clusters(bs, (cluster_offset & s->cluster_offset_mask) & ~511,
|
587 |
nb_csectors * 512);
|
588 |
} else {
|
589 |
free_clusters(bs, cluster_offset, s->cluster_size); |
590 |
} |
591 |
} else {
|
592 |
cluster_offset &= ~QCOW_OFLAG_COPIED; |
593 |
return cluster_offset;
|
594 |
} |
595 |
if (allocate == 1) { |
596 |
/* allocate a new cluster */
|
597 |
cluster_offset = alloc_clusters(bs, s->cluster_size); |
598 |
|
599 |
/* we must initialize the cluster content which won't be
|
600 |
written */
|
601 |
if ((n_end - n_start) < s->cluster_sectors) {
|
602 |
uint64_t start_sect; |
603 |
|
604 |
start_sect = (offset & ~(s->cluster_size - 1)) >> 9; |
605 |
ret = copy_sectors(bs, start_sect, |
606 |
cluster_offset, 0, n_start);
|
607 |
if (ret < 0) |
608 |
return 0; |
609 |
ret = copy_sectors(bs, start_sect, |
610 |
cluster_offset, n_end, s->cluster_sectors); |
611 |
if (ret < 0) |
612 |
return 0; |
613 |
} |
614 |
tmp = cpu_to_be64(cluster_offset | QCOW_OFLAG_COPIED); |
615 |
} else {
|
616 |
int nb_csectors;
|
617 |
cluster_offset = alloc_bytes(bs, compressed_size); |
618 |
nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) - |
619 |
(cluster_offset >> 9);
|
620 |
cluster_offset |= QCOW_OFLAG_COMPRESSED | |
621 |
((uint64_t)nb_csectors << s->csize_shift); |
622 |
/* compressed clusters never have the copied flag */
|
623 |
tmp = cpu_to_be64(cluster_offset); |
624 |
} |
625 |
/* update L2 table */
|
626 |
l2_table[l2_index] = tmp; |
627 |
if (bdrv_pwrite(s->hd,
|
628 |
l2_offset + l2_index * sizeof(tmp), &tmp, sizeof(tmp)) != sizeof(tmp)) |
629 |
return 0; |
630 |
return cluster_offset;
|
631 |
} |
632 |
|
633 |
static int qcow_is_allocated(BlockDriverState *bs, int64_t sector_num, |
634 |
int nb_sectors, int *pnum) |
635 |
{ |
636 |
BDRVQcowState *s = bs->opaque; |
637 |
int index_in_cluster, n;
|
638 |
uint64_t cluster_offset; |
639 |
|
640 |
cluster_offset = get_cluster_offset(bs, sector_num << 9, 0, 0, 0, 0); |
641 |
index_in_cluster = sector_num & (s->cluster_sectors - 1);
|
642 |
n = s->cluster_sectors - index_in_cluster; |
643 |
if (n > nb_sectors)
|
644 |
n = nb_sectors; |
645 |
*pnum = n; |
646 |
return (cluster_offset != 0); |
647 |
} |
648 |
|
649 |
static int decompress_buffer(uint8_t *out_buf, int out_buf_size, |
650 |
const uint8_t *buf, int buf_size) |
651 |
{ |
652 |
z_stream strm1, *strm = &strm1; |
653 |
int ret, out_len;
|
654 |
|
655 |
memset(strm, 0, sizeof(*strm)); |
656 |
|
657 |
strm->next_in = (uint8_t *)buf; |
658 |
strm->avail_in = buf_size; |
659 |
strm->next_out = out_buf; |
660 |
strm->avail_out = out_buf_size; |
661 |
|
662 |
ret = inflateInit2(strm, -12);
|
663 |
if (ret != Z_OK)
|
664 |
return -1; |
665 |
ret = inflate(strm, Z_FINISH); |
666 |
out_len = strm->next_out - out_buf; |
667 |
if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) ||
|
668 |
out_len != out_buf_size) { |
669 |
inflateEnd(strm); |
670 |
return -1; |
671 |
} |
672 |
inflateEnd(strm); |
673 |
return 0; |
674 |
} |
675 |
|
676 |
static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset) |
677 |
{ |
678 |
int ret, csize, nb_csectors, sector_offset;
|
679 |
uint64_t coffset; |
680 |
|
681 |
coffset = cluster_offset & s->cluster_offset_mask; |
682 |
if (s->cluster_cache_offset != coffset) {
|
683 |
nb_csectors = ((cluster_offset >> s->csize_shift) & s->csize_mask) + 1;
|
684 |
sector_offset = coffset & 511;
|
685 |
csize = nb_csectors * 512 - sector_offset;
|
686 |
ret = bdrv_read(s->hd, coffset >> 9, s->cluster_data, nb_csectors);
|
687 |
if (ret < 0) { |
688 |
return -1; |
689 |
} |
690 |
if (decompress_buffer(s->cluster_cache, s->cluster_size,
|
691 |
s->cluster_data + sector_offset, csize) < 0) {
|
692 |
return -1; |
693 |
} |
694 |
s->cluster_cache_offset = coffset; |
695 |
} |
696 |
return 0; |
697 |
} |
698 |
|
699 |
/* handle reading after the end of the backing file */
|
700 |
static int backing_read1(BlockDriverState *bs, |
701 |
int64_t sector_num, uint8_t *buf, int nb_sectors)
|
702 |
{ |
703 |
int n1;
|
704 |
if ((sector_num + nb_sectors) <= bs->total_sectors)
|
705 |
return nb_sectors;
|
706 |
if (sector_num >= bs->total_sectors)
|
707 |
n1 = 0;
|
708 |
else
|
709 |
n1 = bs->total_sectors - sector_num; |
710 |
memset(buf + n1 * 512, 0, 512 * (nb_sectors - n1)); |
711 |
return n1;
|
712 |
} |
713 |
|
714 |
static int qcow_read(BlockDriverState *bs, int64_t sector_num, |
715 |
uint8_t *buf, int nb_sectors)
|
716 |
{ |
717 |
BDRVQcowState *s = bs->opaque; |
718 |
int ret, index_in_cluster, n, n1;
|
719 |
uint64_t cluster_offset; |
720 |
|
721 |
while (nb_sectors > 0) { |
722 |
cluster_offset = get_cluster_offset(bs, sector_num << 9, 0, 0, 0, 0); |
723 |
index_in_cluster = sector_num & (s->cluster_sectors - 1);
|
724 |
n = s->cluster_sectors - index_in_cluster; |
725 |
if (n > nb_sectors)
|
726 |
n = nb_sectors; |
727 |
if (!cluster_offset) {
|
728 |
if (bs->backing_hd) {
|
729 |
/* read from the base image */
|
730 |
n1 = backing_read1(bs->backing_hd, sector_num, buf, n); |
731 |
if (n1 > 0) { |
732 |
ret = bdrv_read(bs->backing_hd, sector_num, buf, n1); |
733 |
if (ret < 0) |
734 |
return -1; |
735 |
} |
736 |
} else {
|
737 |
memset(buf, 0, 512 * n); |
738 |
} |
739 |
} else if (cluster_offset & QCOW_OFLAG_COMPRESSED) { |
740 |
if (decompress_cluster(s, cluster_offset) < 0) |
741 |
return -1; |
742 |
memcpy(buf, s->cluster_cache + index_in_cluster * 512, 512 * n); |
743 |
} else {
|
744 |
ret = bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512); |
745 |
if (ret != n * 512) |
746 |
return -1; |
747 |
if (s->crypt_method) {
|
748 |
encrypt_sectors(s, sector_num, buf, buf, n, 0,
|
749 |
&s->aes_decrypt_key); |
750 |
} |
751 |
} |
752 |
nb_sectors -= n; |
753 |
sector_num += n; |
754 |
buf += n * 512;
|
755 |
} |
756 |
return 0; |
757 |
} |
758 |
|
759 |
static int qcow_write(BlockDriverState *bs, int64_t sector_num, |
760 |
const uint8_t *buf, int nb_sectors) |
761 |
{ |
762 |
BDRVQcowState *s = bs->opaque; |
763 |
int ret, index_in_cluster, n;
|
764 |
uint64_t cluster_offset; |
765 |
|
766 |
while (nb_sectors > 0) { |
767 |
index_in_cluster = sector_num & (s->cluster_sectors - 1);
|
768 |
n = s->cluster_sectors - index_in_cluster; |
769 |
if (n > nb_sectors)
|
770 |
n = nb_sectors; |
771 |
cluster_offset = get_cluster_offset(bs, sector_num << 9, 1, 0, |
772 |
index_in_cluster, |
773 |
index_in_cluster + n); |
774 |
if (!cluster_offset)
|
775 |
return -1; |
776 |
if (s->crypt_method) {
|
777 |
encrypt_sectors(s, sector_num, s->cluster_data, buf, n, 1,
|
778 |
&s->aes_encrypt_key); |
779 |
ret = bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512,
|
780 |
s->cluster_data, n * 512);
|
781 |
} else {
|
782 |
ret = bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512); |
783 |
} |
784 |
if (ret != n * 512) |
785 |
return -1; |
786 |
nb_sectors -= n; |
787 |
sector_num += n; |
788 |
buf += n * 512;
|
789 |
} |
790 |
s->cluster_cache_offset = -1; /* disable compressed cache */ |
791 |
return 0; |
792 |
} |
793 |
|
794 |
typedef struct QCowAIOCB { |
795 |
BlockDriverAIOCB common; |
796 |
int64_t sector_num; |
797 |
uint8_t *buf; |
798 |
int nb_sectors;
|
799 |
int n;
|
800 |
uint64_t cluster_offset; |
801 |
uint8_t *cluster_data; |
802 |
BlockDriverAIOCB *hd_aiocb; |
803 |
} QCowAIOCB; |
804 |
|
805 |
static void qcow_aio_read_cb(void *opaque, int ret) |
806 |
{ |
807 |
QCowAIOCB *acb = opaque; |
808 |
BlockDriverState *bs = acb->common.bs; |
809 |
BDRVQcowState *s = bs->opaque; |
810 |
int index_in_cluster, n1;
|
811 |
|
812 |
acb->hd_aiocb = NULL;
|
813 |
if (ret < 0) { |
814 |
fail:
|
815 |
acb->common.cb(acb->common.opaque, ret); |
816 |
qemu_aio_release(acb); |
817 |
return;
|
818 |
} |
819 |
|
820 |
redo:
|
821 |
/* post process the read buffer */
|
822 |
if (!acb->cluster_offset) {
|
823 |
/* nothing to do */
|
824 |
} else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) { |
825 |
/* nothing to do */
|
826 |
} else {
|
827 |
if (s->crypt_method) {
|
828 |
encrypt_sectors(s, acb->sector_num, acb->buf, acb->buf, |
829 |
acb->n, 0,
|
830 |
&s->aes_decrypt_key); |
831 |
} |
832 |
} |
833 |
|
834 |
acb->nb_sectors -= acb->n; |
835 |
acb->sector_num += acb->n; |
836 |
acb->buf += acb->n * 512;
|
837 |
|
838 |
if (acb->nb_sectors == 0) { |
839 |
/* request completed */
|
840 |
acb->common.cb(acb->common.opaque, 0);
|
841 |
qemu_aio_release(acb); |
842 |
return;
|
843 |
} |
844 |
|
845 |
/* prepare next AIO request */
|
846 |
acb->cluster_offset = get_cluster_offset(bs, acb->sector_num << 9,
|
847 |
0, 0, 0, 0); |
848 |
index_in_cluster = acb->sector_num & (s->cluster_sectors - 1);
|
849 |
acb->n = s->cluster_sectors - index_in_cluster; |
850 |
if (acb->n > acb->nb_sectors)
|
851 |
acb->n = acb->nb_sectors; |
852 |
|
853 |
if (!acb->cluster_offset) {
|
854 |
if (bs->backing_hd) {
|
855 |
/* read from the base image */
|
856 |
n1 = backing_read1(bs->backing_hd, acb->sector_num, |
857 |
acb->buf, acb->n); |
858 |
if (n1 > 0) { |
859 |
acb->hd_aiocb = bdrv_aio_read(bs->backing_hd, acb->sector_num, |
860 |
acb->buf, acb->n, qcow_aio_read_cb, acb); |
861 |
if (acb->hd_aiocb == NULL) |
862 |
goto fail;
|
863 |
} else {
|
864 |
goto redo;
|
865 |
} |
866 |
} else {
|
867 |
/* Note: in this case, no need to wait */
|
868 |
memset(acb->buf, 0, 512 * acb->n); |
869 |
goto redo;
|
870 |
} |
871 |
} else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) { |
872 |
/* add AIO support for compressed blocks ? */
|
873 |
if (decompress_cluster(s, acb->cluster_offset) < 0) |
874 |
goto fail;
|
875 |
memcpy(acb->buf, |
876 |
s->cluster_cache + index_in_cluster * 512, 512 * acb->n); |
877 |
goto redo;
|
878 |
} else {
|
879 |
if ((acb->cluster_offset & 511) != 0) { |
880 |
ret = -EIO; |
881 |
goto fail;
|
882 |
} |
883 |
acb->hd_aiocb = bdrv_aio_read(s->hd, |
884 |
(acb->cluster_offset >> 9) + index_in_cluster,
|
885 |
acb->buf, acb->n, qcow_aio_read_cb, acb); |
886 |
if (acb->hd_aiocb == NULL) |
887 |
goto fail;
|
888 |
} |
889 |
} |
890 |
|
891 |
static QCowAIOCB *qcow_aio_setup(BlockDriverState *bs,
|
892 |
int64_t sector_num, uint8_t *buf, int nb_sectors,
|
893 |
BlockDriverCompletionFunc *cb, void *opaque)
|
894 |
{ |
895 |
QCowAIOCB *acb; |
896 |
|
897 |
acb = qemu_aio_get(bs, cb, opaque); |
898 |
if (!acb)
|
899 |
return NULL; |
900 |
acb->hd_aiocb = NULL;
|
901 |
acb->sector_num = sector_num; |
902 |
acb->buf = buf; |
903 |
acb->nb_sectors = nb_sectors; |
904 |
acb->n = 0;
|
905 |
acb->cluster_offset = 0;
|
906 |
return acb;
|
907 |
} |
908 |
|
909 |
static BlockDriverAIOCB *qcow_aio_read(BlockDriverState *bs,
|
910 |
int64_t sector_num, uint8_t *buf, int nb_sectors,
|
911 |
BlockDriverCompletionFunc *cb, void *opaque)
|
912 |
{ |
913 |
QCowAIOCB *acb; |
914 |
|
915 |
acb = qcow_aio_setup(bs, sector_num, buf, nb_sectors, cb, opaque); |
916 |
if (!acb)
|
917 |
return NULL; |
918 |
|
919 |
qcow_aio_read_cb(acb, 0);
|
920 |
return &acb->common;
|
921 |
} |
922 |
|
923 |
static void qcow_aio_write_cb(void *opaque, int ret) |
924 |
{ |
925 |
QCowAIOCB *acb = opaque; |
926 |
BlockDriverState *bs = acb->common.bs; |
927 |
BDRVQcowState *s = bs->opaque; |
928 |
int index_in_cluster;
|
929 |
uint64_t cluster_offset; |
930 |
const uint8_t *src_buf;
|
931 |
|
932 |
acb->hd_aiocb = NULL;
|
933 |
|
934 |
if (ret < 0) { |
935 |
fail:
|
936 |
acb->common.cb(acb->common.opaque, ret); |
937 |
qemu_aio_release(acb); |
938 |
return;
|
939 |
} |
940 |
|
941 |
acb->nb_sectors -= acb->n; |
942 |
acb->sector_num += acb->n; |
943 |
acb->buf += acb->n * 512;
|
944 |
|
945 |
if (acb->nb_sectors == 0) { |
946 |
/* request completed */
|
947 |
acb->common.cb(acb->common.opaque, 0);
|
948 |
qemu_aio_release(acb); |
949 |
return;
|
950 |
} |
951 |
|
952 |
index_in_cluster = acb->sector_num & (s->cluster_sectors - 1);
|
953 |
acb->n = s->cluster_sectors - index_in_cluster; |
954 |
if (acb->n > acb->nb_sectors)
|
955 |
acb->n = acb->nb_sectors; |
956 |
cluster_offset = get_cluster_offset(bs, acb->sector_num << 9, 1, 0, |
957 |
index_in_cluster, |
958 |
index_in_cluster + acb->n); |
959 |
if (!cluster_offset || (cluster_offset & 511) != 0) { |
960 |
ret = -EIO; |
961 |
goto fail;
|
962 |
} |
963 |
if (s->crypt_method) {
|
964 |
if (!acb->cluster_data) {
|
965 |
acb->cluster_data = qemu_mallocz(s->cluster_size); |
966 |
if (!acb->cluster_data) {
|
967 |
ret = -ENOMEM; |
968 |
goto fail;
|
969 |
} |
970 |
} |
971 |
encrypt_sectors(s, acb->sector_num, acb->cluster_data, acb->buf, |
972 |
acb->n, 1, &s->aes_encrypt_key);
|
973 |
src_buf = acb->cluster_data; |
974 |
} else {
|
975 |
src_buf = acb->buf; |
976 |
} |
977 |
acb->hd_aiocb = bdrv_aio_write(s->hd, |
978 |
(cluster_offset >> 9) + index_in_cluster,
|
979 |
src_buf, acb->n, |
980 |
qcow_aio_write_cb, acb); |
981 |
if (acb->hd_aiocb == NULL) |
982 |
goto fail;
|
983 |
} |
984 |
|
985 |
static BlockDriverAIOCB *qcow_aio_write(BlockDriverState *bs,
|
986 |
int64_t sector_num, const uint8_t *buf, int nb_sectors, |
987 |
BlockDriverCompletionFunc *cb, void *opaque)
|
988 |
{ |
989 |
BDRVQcowState *s = bs->opaque; |
990 |
QCowAIOCB *acb; |
991 |
|
992 |
s->cluster_cache_offset = -1; /* disable compressed cache */ |
993 |
|
994 |
acb = qcow_aio_setup(bs, sector_num, (uint8_t*)buf, nb_sectors, cb, opaque); |
995 |
if (!acb)
|
996 |
return NULL; |
997 |
|
998 |
qcow_aio_write_cb(acb, 0);
|
999 |
return &acb->common;
|
1000 |
} |
1001 |
|
1002 |
static void qcow_aio_cancel(BlockDriverAIOCB *blockacb) |
1003 |
{ |
1004 |
QCowAIOCB *acb = (QCowAIOCB *)blockacb; |
1005 |
if (acb->hd_aiocb)
|
1006 |
bdrv_aio_cancel(acb->hd_aiocb); |
1007 |
qemu_aio_release(acb); |
1008 |
} |
1009 |
|
1010 |
static void qcow_close(BlockDriverState *bs) |
1011 |
{ |
1012 |
BDRVQcowState *s = bs->opaque; |
1013 |
qemu_free(s->l1_table); |
1014 |
qemu_free(s->l2_cache); |
1015 |
qemu_free(s->cluster_cache); |
1016 |
qemu_free(s->cluster_data); |
1017 |
refcount_close(bs); |
1018 |
bdrv_delete(s->hd); |
1019 |
} |
1020 |
|
1021 |
/* XXX: use std qcow open function ? */
|
1022 |
typedef struct QCowCreateState { |
1023 |
int cluster_size;
|
1024 |
int cluster_bits;
|
1025 |
uint16_t *refcount_block; |
1026 |
uint64_t *refcount_table; |
1027 |
int64_t l1_table_offset; |
1028 |
int64_t refcount_table_offset; |
1029 |
int64_t refcount_block_offset; |
1030 |
} QCowCreateState; |
1031 |
|
1032 |
static void create_refcount_update(QCowCreateState *s, |
1033 |
int64_t offset, int64_t size) |
1034 |
{ |
1035 |
int refcount;
|
1036 |
int64_t start, last, cluster_offset; |
1037 |
uint16_t *p; |
1038 |
|
1039 |
start = offset & ~(s->cluster_size - 1);
|
1040 |
last = (offset + size - 1) & ~(s->cluster_size - 1); |
1041 |
for(cluster_offset = start; cluster_offset <= last;
|
1042 |
cluster_offset += s->cluster_size) { |
1043 |
p = &s->refcount_block[cluster_offset >> s->cluster_bits]; |
1044 |
refcount = be16_to_cpu(*p); |
1045 |
refcount++; |
1046 |
*p = cpu_to_be16(refcount); |
1047 |
} |
1048 |
} |
1049 |
|
1050 |
static int qcow_create(const char *filename, int64_t total_size, |
1051 |
const char *backing_file, int flags) |
1052 |
{ |
1053 |
int fd, header_size, backing_filename_len, l1_size, i, shift, l2_bits;
|
1054 |
QCowHeader header; |
1055 |
uint64_t tmp, offset; |
1056 |
QCowCreateState s1, *s = &s1; |
1057 |
|
1058 |
memset(s, 0, sizeof(*s)); |
1059 |
|
1060 |
fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0644);
|
1061 |
if (fd < 0) |
1062 |
return -1; |
1063 |
memset(&header, 0, sizeof(header)); |
1064 |
header.magic = cpu_to_be32(QCOW_MAGIC); |
1065 |
header.version = cpu_to_be32(QCOW_VERSION); |
1066 |
header.size = cpu_to_be64(total_size * 512);
|
1067 |
header_size = sizeof(header);
|
1068 |
backing_filename_len = 0;
|
1069 |
if (backing_file) {
|
1070 |
header.backing_file_offset = cpu_to_be64(header_size); |
1071 |
backing_filename_len = strlen(backing_file); |
1072 |
header.backing_file_size = cpu_to_be32(backing_filename_len); |
1073 |
header_size += backing_filename_len; |
1074 |
} |
1075 |
s->cluster_bits = 12; /* 4 KB clusters */ |
1076 |
s->cluster_size = 1 << s->cluster_bits;
|
1077 |
header.cluster_bits = cpu_to_be32(s->cluster_bits); |
1078 |
header_size = (header_size + 7) & ~7; |
1079 |
if (flags & BLOCK_FLAG_ENCRYPT) {
|
1080 |
header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES); |
1081 |
} else {
|
1082 |
header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE); |
1083 |
} |
1084 |
l2_bits = s->cluster_bits - 3;
|
1085 |
shift = s->cluster_bits + l2_bits; |
1086 |
l1_size = (((total_size * 512) + (1LL << shift) - 1) >> shift); |
1087 |
offset = align_offset(header_size, s->cluster_size); |
1088 |
s->l1_table_offset = offset; |
1089 |
header.l1_table_offset = cpu_to_be64(s->l1_table_offset); |
1090 |
header.l1_size = cpu_to_be32(l1_size); |
1091 |
offset += align_offset(l1_size * sizeof(uint64_t), s->cluster_size);
|
1092 |
|
1093 |
s->refcount_table = qemu_mallocz(s->cluster_size); |
1094 |
if (!s->refcount_table)
|
1095 |
goto fail;
|
1096 |
s->refcount_block = qemu_mallocz(s->cluster_size); |
1097 |
if (!s->refcount_block)
|
1098 |
goto fail;
|
1099 |
|
1100 |
s->refcount_table_offset = offset; |
1101 |
header.refcount_table_offset = cpu_to_be64(offset); |
1102 |
header.refcount_table_clusters = cpu_to_be32(1);
|
1103 |
offset += s->cluster_size; |
1104 |
|
1105 |
s->refcount_table[0] = cpu_to_be64(offset);
|
1106 |
s->refcount_block_offset = offset; |
1107 |
offset += s->cluster_size; |
1108 |
|
1109 |
/* update refcounts */
|
1110 |
create_refcount_update(s, 0, header_size);
|
1111 |
create_refcount_update(s, s->l1_table_offset, l1_size * sizeof(uint64_t));
|
1112 |
create_refcount_update(s, s->refcount_table_offset, s->cluster_size); |
1113 |
create_refcount_update(s, s->refcount_block_offset, s->cluster_size); |
1114 |
|
1115 |
/* write all the data */
|
1116 |
write(fd, &header, sizeof(header));
|
1117 |
if (backing_file) {
|
1118 |
write(fd, backing_file, backing_filename_len); |
1119 |
} |
1120 |
lseek(fd, s->l1_table_offset, SEEK_SET); |
1121 |
tmp = 0;
|
1122 |
for(i = 0;i < l1_size; i++) { |
1123 |
write(fd, &tmp, sizeof(tmp));
|
1124 |
} |
1125 |
lseek(fd, s->refcount_table_offset, SEEK_SET); |
1126 |
write(fd, s->refcount_table, s->cluster_size); |
1127 |
|
1128 |
lseek(fd, s->refcount_block_offset, SEEK_SET); |
1129 |
write(fd, s->refcount_block, s->cluster_size); |
1130 |
|
1131 |
qemu_free(s->refcount_table); |
1132 |
qemu_free(s->refcount_block); |
1133 |
close(fd); |
1134 |
return 0; |
1135 |
fail:
|
1136 |
qemu_free(s->refcount_table); |
1137 |
qemu_free(s->refcount_block); |
1138 |
close(fd); |
1139 |
return -ENOMEM;
|
1140 |
} |
1141 |
|
1142 |
static int qcow_make_empty(BlockDriverState *bs) |
1143 |
{ |
1144 |
#if 0
|
1145 |
/* XXX: not correct */
|
1146 |
BDRVQcowState *s = bs->opaque;
|
1147 |
uint32_t l1_length = s->l1_size * sizeof(uint64_t);
|
1148 |
int ret;
|
1149 |
|
1150 |
memset(s->l1_table, 0, l1_length);
|
1151 |
if (bdrv_pwrite(s->hd, s->l1_table_offset, s->l1_table, l1_length) < 0)
|
1152 |
return -1;
|
1153 |
ret = bdrv_truncate(s->hd, s->l1_table_offset + l1_length);
|
1154 |
if (ret < 0)
|
1155 |
return ret;
|
1156 |
|
1157 |
l2_cache_reset(bs);
|
1158 |
#endif
|
1159 |
return 0; |
1160 |
} |
1161 |
|
1162 |
/* XXX: put compressed sectors first, then all the cluster aligned
|
1163 |
tables to avoid losing bytes in alignment */
|
1164 |
static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num, |
1165 |
const uint8_t *buf, int nb_sectors) |
1166 |
{ |
1167 |
BDRVQcowState *s = bs->opaque; |
1168 |
z_stream strm; |
1169 |
int ret, out_len;
|
1170 |
uint8_t *out_buf; |
1171 |
uint64_t cluster_offset; |
1172 |
|
1173 |
if (nb_sectors == 0) { |
1174 |
/* align end of file to a sector boundary to ease reading with
|
1175 |
sector based I/Os */
|
1176 |
cluster_offset = bdrv_getlength(s->hd); |
1177 |
cluster_offset = (cluster_offset + 511) & ~511; |
1178 |
bdrv_truncate(s->hd, cluster_offset); |
1179 |
return 0; |
1180 |
} |
1181 |
|
1182 |
if (nb_sectors != s->cluster_sectors)
|
1183 |
return -EINVAL;
|
1184 |
|
1185 |
out_buf = qemu_malloc(s->cluster_size + (s->cluster_size / 1000) + 128); |
1186 |
if (!out_buf)
|
1187 |
return -ENOMEM;
|
1188 |
|
1189 |
/* best compression, small window, no zlib header */
|
1190 |
memset(&strm, 0, sizeof(strm)); |
1191 |
ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, |
1192 |
Z_DEFLATED, -12,
|
1193 |
9, Z_DEFAULT_STRATEGY);
|
1194 |
if (ret != 0) { |
1195 |
qemu_free(out_buf); |
1196 |
return -1; |
1197 |
} |
1198 |
|
1199 |
strm.avail_in = s->cluster_size; |
1200 |
strm.next_in = (uint8_t *)buf; |
1201 |
strm.avail_out = s->cluster_size; |
1202 |
strm.next_out = out_buf; |
1203 |
|
1204 |
ret = deflate(&strm, Z_FINISH); |
1205 |
if (ret != Z_STREAM_END && ret != Z_OK) {
|
1206 |
qemu_free(out_buf); |
1207 |
deflateEnd(&strm); |
1208 |
return -1; |
1209 |
} |
1210 |
out_len = strm.next_out - out_buf; |
1211 |
|
1212 |
deflateEnd(&strm); |
1213 |
|
1214 |
if (ret != Z_STREAM_END || out_len >= s->cluster_size) {
|
1215 |
/* could not compress: write normal cluster */
|
1216 |
qcow_write(bs, sector_num, buf, s->cluster_sectors); |
1217 |
} else {
|
1218 |
cluster_offset = get_cluster_offset(bs, sector_num << 9, 2, |
1219 |
out_len, 0, 0); |
1220 |
cluster_offset &= s->cluster_offset_mask; |
1221 |
if (bdrv_pwrite(s->hd, cluster_offset, out_buf, out_len) != out_len) {
|
1222 |
qemu_free(out_buf); |
1223 |
return -1; |
1224 |
} |
1225 |
} |
1226 |
|
1227 |
qemu_free(out_buf); |
1228 |
return 0; |
1229 |
} |
1230 |
|
1231 |
static void qcow_flush(BlockDriverState *bs) |
1232 |
{ |
1233 |
BDRVQcowState *s = bs->opaque; |
1234 |
bdrv_flush(s->hd); |
1235 |
} |
1236 |
|
1237 |
static int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
1238 |
{ |
1239 |
BDRVQcowState *s = bs->opaque; |
1240 |
bdi->cluster_size = s->cluster_size; |
1241 |
bdi->vm_state_offset = (int64_t)s->l1_vm_state_index << |
1242 |
(s->cluster_bits + s->l2_bits); |
1243 |
return 0; |
1244 |
} |
1245 |
|
1246 |
/*********************************************************/
|
1247 |
/* snapshot support */
|
1248 |
|
1249 |
/* update the refcounts of snapshots and the copied flag */
|
1250 |
static int update_snapshot_refcount(BlockDriverState *bs, |
1251 |
int64_t l1_table_offset, |
1252 |
int l1_size,
|
1253 |
int addend)
|
1254 |
{ |
1255 |
BDRVQcowState *s = bs->opaque; |
1256 |
uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2, l1_allocated; |
1257 |
int64_t old_offset, old_l2_offset; |
1258 |
int l2_size, i, j, l1_modified, l2_modified, nb_csectors, refcount;
|
1259 |
|
1260 |
l2_cache_reset(bs); |
1261 |
|
1262 |
l2_table = NULL;
|
1263 |
l1_table = NULL;
|
1264 |
l1_size2 = l1_size * sizeof(uint64_t);
|
1265 |
l1_allocated = 0;
|
1266 |
if (l1_table_offset != s->l1_table_offset) {
|
1267 |
l1_table = qemu_malloc(l1_size2); |
1268 |
if (!l1_table)
|
1269 |
goto fail;
|
1270 |
l1_allocated = 1;
|
1271 |
if (bdrv_pread(s->hd, l1_table_offset,
|
1272 |
l1_table, l1_size2) != l1_size2) |
1273 |
goto fail;
|
1274 |
for(i = 0;i < l1_size; i++) |
1275 |
be64_to_cpus(&l1_table[i]); |
1276 |
} else {
|
1277 |
assert(l1_size == s->l1_size); |
1278 |
l1_table = s->l1_table; |
1279 |
l1_allocated = 0;
|
1280 |
} |
1281 |
|
1282 |
l2_size = s->l2_size * sizeof(uint64_t);
|
1283 |
l2_table = qemu_malloc(l2_size); |
1284 |
if (!l2_table)
|
1285 |
goto fail;
|
1286 |
l1_modified = 0;
|
1287 |
for(i = 0; i < l1_size; i++) { |
1288 |
l2_offset = l1_table[i]; |
1289 |
if (l2_offset) {
|
1290 |
old_l2_offset = l2_offset; |
1291 |
l2_offset &= ~QCOW_OFLAG_COPIED; |
1292 |
l2_modified = 0;
|
1293 |
if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size)
|
1294 |
goto fail;
|
1295 |
for(j = 0; j < s->l2_size; j++) { |
1296 |
offset = be64_to_cpu(l2_table[j]); |
1297 |
if (offset != 0) { |
1298 |
old_offset = offset; |
1299 |
offset &= ~QCOW_OFLAG_COPIED; |
1300 |
if (offset & QCOW_OFLAG_COMPRESSED) {
|
1301 |
nb_csectors = ((offset >> s->csize_shift) & |
1302 |
s->csize_mask) + 1;
|
1303 |
if (addend != 0) |
1304 |
update_refcount(bs, (offset & s->cluster_offset_mask) & ~511,
|
1305 |
nb_csectors * 512, addend);
|
1306 |
/* compressed clusters are never modified */
|
1307 |
refcount = 2;
|
1308 |
} else {
|
1309 |
if (addend != 0) { |
1310 |
refcount = update_cluster_refcount(bs, offset >> s->cluster_bits, addend); |
1311 |
} else {
|
1312 |
refcount = get_refcount(bs, offset >> s->cluster_bits); |
1313 |
} |
1314 |
} |
1315 |
|
1316 |
if (refcount == 1) { |
1317 |
offset |= QCOW_OFLAG_COPIED; |
1318 |
} |
1319 |
if (offset != old_offset) {
|
1320 |
l2_table[j] = cpu_to_be64(offset); |
1321 |
l2_modified = 1;
|
1322 |
} |
1323 |
} |
1324 |
} |
1325 |
if (l2_modified) {
|
1326 |
if (bdrv_pwrite(s->hd,
|
1327 |
l2_offset, l2_table, l2_size) != l2_size) |
1328 |
goto fail;
|
1329 |
} |
1330 |
|
1331 |
if (addend != 0) { |
1332 |
refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend); |
1333 |
} else {
|
1334 |
refcount = get_refcount(bs, l2_offset >> s->cluster_bits); |
1335 |
} |
1336 |
if (refcount == 1) { |
1337 |
l2_offset |= QCOW_OFLAG_COPIED; |
1338 |
} |
1339 |
if (l2_offset != old_l2_offset) {
|
1340 |
l1_table[i] = l2_offset; |
1341 |
l1_modified = 1;
|
1342 |
} |
1343 |
} |
1344 |
} |
1345 |
if (l1_modified) {
|
1346 |
for(i = 0; i < l1_size; i++) |
1347 |
cpu_to_be64s(&l1_table[i]); |
1348 |
if (bdrv_pwrite(s->hd, l1_table_offset, l1_table,
|
1349 |
l1_size2) != l1_size2) |
1350 |
goto fail;
|
1351 |
for(i = 0; i < l1_size; i++) |
1352 |
be64_to_cpus(&l1_table[i]); |
1353 |
} |
1354 |
if (l1_allocated)
|
1355 |
qemu_free(l1_table); |
1356 |
qemu_free(l2_table); |
1357 |
return 0; |
1358 |
fail:
|
1359 |
if (l1_allocated)
|
1360 |
qemu_free(l1_table); |
1361 |
qemu_free(l2_table); |
1362 |
return -EIO;
|
1363 |
} |
1364 |
|
1365 |
static void qcow_free_snapshots(BlockDriverState *bs) |
1366 |
{ |
1367 |
BDRVQcowState *s = bs->opaque; |
1368 |
int i;
|
1369 |
|
1370 |
for(i = 0; i < s->nb_snapshots; i++) { |
1371 |
qemu_free(s->snapshots[i].name); |
1372 |
qemu_free(s->snapshots[i].id_str); |
1373 |
} |
1374 |
qemu_free(s->snapshots); |
1375 |
s->snapshots = NULL;
|
1376 |
s->nb_snapshots = 0;
|
1377 |
} |
1378 |
|
1379 |
static int qcow_read_snapshots(BlockDriverState *bs) |
1380 |
{ |
1381 |
BDRVQcowState *s = bs->opaque; |
1382 |
QCowSnapshotHeader h; |
1383 |
QCowSnapshot *sn; |
1384 |
int i, id_str_size, name_size;
|
1385 |
int64_t offset; |
1386 |
uint32_t extra_data_size; |
1387 |
|
1388 |
offset = s->snapshots_offset; |
1389 |
s->snapshots = qemu_mallocz(s->nb_snapshots * sizeof(QCowSnapshot));
|
1390 |
if (!s->snapshots)
|
1391 |
goto fail;
|
1392 |
for(i = 0; i < s->nb_snapshots; i++) { |
1393 |
offset = align_offset(offset, 8);
|
1394 |
if (bdrv_pread(s->hd, offset, &h, sizeof(h)) != sizeof(h)) |
1395 |
goto fail;
|
1396 |
offset += sizeof(h);
|
1397 |
sn = s->snapshots + i; |
1398 |
sn->l1_table_offset = be64_to_cpu(h.l1_table_offset); |
1399 |
sn->l1_size = be32_to_cpu(h.l1_size); |
1400 |
sn->vm_state_size = be32_to_cpu(h.vm_state_size); |
1401 |
sn->date_sec = be32_to_cpu(h.date_sec); |
1402 |
sn->date_nsec = be32_to_cpu(h.date_nsec); |
1403 |
sn->vm_clock_nsec = be64_to_cpu(h.vm_clock_nsec); |
1404 |
extra_data_size = be32_to_cpu(h.extra_data_size); |
1405 |
|
1406 |
id_str_size = be16_to_cpu(h.id_str_size); |
1407 |
name_size = be16_to_cpu(h.name_size); |
1408 |
|
1409 |
offset += extra_data_size; |
1410 |
|
1411 |
sn->id_str = qemu_malloc(id_str_size + 1);
|
1412 |
if (!sn->id_str)
|
1413 |
goto fail;
|
1414 |
if (bdrv_pread(s->hd, offset, sn->id_str, id_str_size) != id_str_size)
|
1415 |
goto fail;
|
1416 |
offset += id_str_size; |
1417 |
sn->id_str[id_str_size] = '\0';
|
1418 |
|
1419 |
sn->name = qemu_malloc(name_size + 1);
|
1420 |
if (!sn->name)
|
1421 |
goto fail;
|
1422 |
if (bdrv_pread(s->hd, offset, sn->name, name_size) != name_size)
|
1423 |
goto fail;
|
1424 |
offset += name_size; |
1425 |
sn->name[name_size] = '\0';
|
1426 |
} |
1427 |
s->snapshots_size = offset - s->snapshots_offset; |
1428 |
return 0; |
1429 |
fail:
|
1430 |
qcow_free_snapshots(bs); |
1431 |
return -1; |
1432 |
} |
1433 |
|
1434 |
/* add at the end of the file a new list of snapshots */
|
1435 |
static int qcow_write_snapshots(BlockDriverState *bs) |
1436 |
{ |
1437 |
BDRVQcowState *s = bs->opaque; |
1438 |
QCowSnapshot *sn; |
1439 |
QCowSnapshotHeader h; |
1440 |
int i, name_size, id_str_size, snapshots_size;
|
1441 |
uint64_t data64; |
1442 |
uint32_t data32; |
1443 |
int64_t offset, snapshots_offset; |
1444 |
|
1445 |
/* compute the size of the snapshots */
|
1446 |
offset = 0;
|
1447 |
for(i = 0; i < s->nb_snapshots; i++) { |
1448 |
sn = s->snapshots + i; |
1449 |
offset = align_offset(offset, 8);
|
1450 |
offset += sizeof(h);
|
1451 |
offset += strlen(sn->id_str); |
1452 |
offset += strlen(sn->name); |
1453 |
} |
1454 |
snapshots_size = offset; |
1455 |
|
1456 |
snapshots_offset = alloc_clusters(bs, snapshots_size); |
1457 |
offset = snapshots_offset; |
1458 |
|
1459 |
for(i = 0; i < s->nb_snapshots; i++) { |
1460 |
sn = s->snapshots + i; |
1461 |
memset(&h, 0, sizeof(h)); |
1462 |
h.l1_table_offset = cpu_to_be64(sn->l1_table_offset); |
1463 |
h.l1_size = cpu_to_be32(sn->l1_size); |
1464 |
h.vm_state_size = cpu_to_be32(sn->vm_state_size); |
1465 |
h.date_sec = cpu_to_be32(sn->date_sec); |
1466 |
h.date_nsec = cpu_to_be32(sn->date_nsec); |
1467 |
h.vm_clock_nsec = cpu_to_be64(sn->vm_clock_nsec); |
1468 |
|
1469 |
id_str_size = strlen(sn->id_str); |
1470 |
name_size = strlen(sn->name); |
1471 |
h.id_str_size = cpu_to_be16(id_str_size); |
1472 |
h.name_size = cpu_to_be16(name_size); |
1473 |
offset = align_offset(offset, 8);
|
1474 |
if (bdrv_pwrite(s->hd, offset, &h, sizeof(h)) != sizeof(h)) |
1475 |
goto fail;
|
1476 |
offset += sizeof(h);
|
1477 |
if (bdrv_pwrite(s->hd, offset, sn->id_str, id_str_size) != id_str_size)
|
1478 |
goto fail;
|
1479 |
offset += id_str_size; |
1480 |
if (bdrv_pwrite(s->hd, offset, sn->name, name_size) != name_size)
|
1481 |
goto fail;
|
1482 |
offset += name_size; |
1483 |
} |
1484 |
|
1485 |
/* update the various header fields */
|
1486 |
data64 = cpu_to_be64(snapshots_offset); |
1487 |
if (bdrv_pwrite(s->hd, offsetof(QCowHeader, snapshots_offset),
|
1488 |
&data64, sizeof(data64)) != sizeof(data64)) |
1489 |
goto fail;
|
1490 |
data32 = cpu_to_be32(s->nb_snapshots); |
1491 |
if (bdrv_pwrite(s->hd, offsetof(QCowHeader, nb_snapshots),
|
1492 |
&data32, sizeof(data32)) != sizeof(data32)) |
1493 |
goto fail;
|
1494 |
|
1495 |
/* free the old snapshot table */
|
1496 |
free_clusters(bs, s->snapshots_offset, s->snapshots_size); |
1497 |
s->snapshots_offset = snapshots_offset; |
1498 |
s->snapshots_size = snapshots_size; |
1499 |
return 0; |
1500 |
fail:
|
1501 |
return -1; |
1502 |
} |
1503 |
|
1504 |
static void find_new_snapshot_id(BlockDriverState *bs, |
1505 |
char *id_str, int id_str_size) |
1506 |
{ |
1507 |
BDRVQcowState *s = bs->opaque; |
1508 |
QCowSnapshot *sn; |
1509 |
int i, id, id_max = 0; |
1510 |
|
1511 |
for(i = 0; i < s->nb_snapshots; i++) { |
1512 |
sn = s->snapshots + i; |
1513 |
id = strtoul(sn->id_str, NULL, 10); |
1514 |
if (id > id_max)
|
1515 |
id_max = id; |
1516 |
} |
1517 |
snprintf(id_str, id_str_size, "%d", id_max + 1); |
1518 |
} |
1519 |
|
1520 |
static int find_snapshot_by_id(BlockDriverState *bs, const char *id_str) |
1521 |
{ |
1522 |
BDRVQcowState *s = bs->opaque; |
1523 |
int i;
|
1524 |
|
1525 |
for(i = 0; i < s->nb_snapshots; i++) { |
1526 |
if (!strcmp(s->snapshots[i].id_str, id_str))
|
1527 |
return i;
|
1528 |
} |
1529 |
return -1; |
1530 |
} |
1531 |
|
1532 |
static int find_snapshot_by_id_or_name(BlockDriverState *bs, const char *name) |
1533 |
{ |
1534 |
BDRVQcowState *s = bs->opaque; |
1535 |
int i, ret;
|
1536 |
|
1537 |
ret = find_snapshot_by_id(bs, name); |
1538 |
if (ret >= 0) |
1539 |
return ret;
|
1540 |
for(i = 0; i < s->nb_snapshots; i++) { |
1541 |
if (!strcmp(s->snapshots[i].name, name))
|
1542 |
return i;
|
1543 |
} |
1544 |
return -1; |
1545 |
} |
1546 |
|
1547 |
/* if no id is provided, a new one is constructed */
|
1548 |
static int qcow_snapshot_create(BlockDriverState *bs, |
1549 |
QEMUSnapshotInfo *sn_info) |
1550 |
{ |
1551 |
BDRVQcowState *s = bs->opaque; |
1552 |
QCowSnapshot *snapshots1, sn1, *sn = &sn1; |
1553 |
int i, ret;
|
1554 |
uint64_t *l1_table = NULL;
|
1555 |
|
1556 |
memset(sn, 0, sizeof(*sn)); |
1557 |
|
1558 |
if (sn_info->id_str[0] == '\0') { |
1559 |
/* compute a new id */
|
1560 |
find_new_snapshot_id(bs, sn_info->id_str, sizeof(sn_info->id_str));
|
1561 |
} |
1562 |
|
1563 |
/* check that the ID is unique */
|
1564 |
if (find_snapshot_by_id(bs, sn_info->id_str) >= 0) |
1565 |
return -ENOENT;
|
1566 |
|
1567 |
sn->id_str = qemu_strdup(sn_info->id_str); |
1568 |
if (!sn->id_str)
|
1569 |
goto fail;
|
1570 |
sn->name = qemu_strdup(sn_info->name); |
1571 |
if (!sn->name)
|
1572 |
goto fail;
|
1573 |
sn->vm_state_size = sn_info->vm_state_size; |
1574 |
sn->date_sec = sn_info->date_sec; |
1575 |
sn->date_nsec = sn_info->date_nsec; |
1576 |
sn->vm_clock_nsec = sn_info->vm_clock_nsec; |
1577 |
|
1578 |
ret = update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1);
|
1579 |
if (ret < 0) |
1580 |
goto fail;
|
1581 |
|
1582 |
/* create the L1 table of the snapshot */
|
1583 |
sn->l1_table_offset = alloc_clusters(bs, s->l1_size * sizeof(uint64_t));
|
1584 |
sn->l1_size = s->l1_size; |
1585 |
|
1586 |
l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t));
|
1587 |
if (!l1_table)
|
1588 |
goto fail;
|
1589 |
for(i = 0; i < s->l1_size; i++) { |
1590 |
l1_table[i] = cpu_to_be64(s->l1_table[i]); |
1591 |
} |
1592 |
if (bdrv_pwrite(s->hd, sn->l1_table_offset,
|
1593 |
l1_table, s->l1_size * sizeof(uint64_t)) !=
|
1594 |
(s->l1_size * sizeof(uint64_t)))
|
1595 |
goto fail;
|
1596 |
qemu_free(l1_table); |
1597 |
l1_table = NULL;
|
1598 |
|
1599 |
snapshots1 = qemu_malloc((s->nb_snapshots + 1) * sizeof(QCowSnapshot)); |
1600 |
if (!snapshots1)
|
1601 |
goto fail;
|
1602 |
memcpy(snapshots1, s->snapshots, s->nb_snapshots * sizeof(QCowSnapshot));
|
1603 |
s->snapshots = snapshots1; |
1604 |
s->snapshots[s->nb_snapshots++] = *sn; |
1605 |
|
1606 |
if (qcow_write_snapshots(bs) < 0) |
1607 |
goto fail;
|
1608 |
#ifdef DEBUG_ALLOC
|
1609 |
check_refcounts(bs); |
1610 |
#endif
|
1611 |
return 0; |
1612 |
fail:
|
1613 |
qemu_free(sn->name); |
1614 |
qemu_free(l1_table); |
1615 |
return -1; |
1616 |
} |
1617 |
|
1618 |
/* copy the snapshot 'snapshot_name' into the current disk image */
|
1619 |
static int qcow_snapshot_goto(BlockDriverState *bs, |
1620 |
const char *snapshot_id) |
1621 |
{ |
1622 |
BDRVQcowState *s = bs->opaque; |
1623 |
QCowSnapshot *sn; |
1624 |
int i, snapshot_index, l1_size2;
|
1625 |
|
1626 |
snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id); |
1627 |
if (snapshot_index < 0) |
1628 |
return -ENOENT;
|
1629 |
sn = &s->snapshots[snapshot_index]; |
1630 |
|
1631 |
if (update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, -1) < 0) |
1632 |
goto fail;
|
1633 |
|
1634 |
if (grow_l1_table(bs, sn->l1_size) < 0) |
1635 |
goto fail;
|
1636 |
|
1637 |
s->l1_size = sn->l1_size; |
1638 |
l1_size2 = s->l1_size * sizeof(uint64_t);
|
1639 |
/* copy the snapshot l1 table to the current l1 table */
|
1640 |
if (bdrv_pread(s->hd, sn->l1_table_offset,
|
1641 |
s->l1_table, l1_size2) != l1_size2) |
1642 |
goto fail;
|
1643 |
if (bdrv_pwrite(s->hd, s->l1_table_offset,
|
1644 |
s->l1_table, l1_size2) != l1_size2) |
1645 |
goto fail;
|
1646 |
for(i = 0;i < s->l1_size; i++) { |
1647 |
be64_to_cpus(&s->l1_table[i]); |
1648 |
} |
1649 |
|
1650 |
if (update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1) < 0) |
1651 |
goto fail;
|
1652 |
|
1653 |
#ifdef DEBUG_ALLOC
|
1654 |
check_refcounts(bs); |
1655 |
#endif
|
1656 |
return 0; |
1657 |
fail:
|
1658 |
return -EIO;
|
1659 |
} |
1660 |
|
1661 |
static int qcow_snapshot_delete(BlockDriverState *bs, const char *snapshot_id) |
1662 |
{ |
1663 |
BDRVQcowState *s = bs->opaque; |
1664 |
QCowSnapshot *sn; |
1665 |
int snapshot_index, ret;
|
1666 |
|
1667 |
snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id); |
1668 |
if (snapshot_index < 0) |
1669 |
return -ENOENT;
|
1670 |
sn = &s->snapshots[snapshot_index]; |
1671 |
|
1672 |
ret = update_snapshot_refcount(bs, sn->l1_table_offset, sn->l1_size, -1);
|
1673 |
if (ret < 0) |
1674 |
return ret;
|
1675 |
/* must update the copied flag on the current cluster offsets */
|
1676 |
ret = update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 0);
|
1677 |
if (ret < 0) |
1678 |
return ret;
|
1679 |
free_clusters(bs, sn->l1_table_offset, sn->l1_size * sizeof(uint64_t));
|
1680 |
|
1681 |
qemu_free(sn->id_str); |
1682 |
qemu_free(sn->name); |
1683 |
memmove(sn, sn + 1, (s->nb_snapshots - snapshot_index - 1) * sizeof(*sn)); |
1684 |
s->nb_snapshots--; |
1685 |
ret = qcow_write_snapshots(bs); |
1686 |
if (ret < 0) { |
1687 |
/* XXX: restore snapshot if error ? */
|
1688 |
return ret;
|
1689 |
} |
1690 |
#ifdef DEBUG_ALLOC
|
1691 |
check_refcounts(bs); |
1692 |
#endif
|
1693 |
return 0; |
1694 |
} |
1695 |
|
1696 |
static int qcow_snapshot_list(BlockDriverState *bs, |
1697 |
QEMUSnapshotInfo **psn_tab) |
1698 |
{ |
1699 |
BDRVQcowState *s = bs->opaque; |
1700 |
QEMUSnapshotInfo *sn_tab, *sn_info; |
1701 |
QCowSnapshot *sn; |
1702 |
int i;
|
1703 |
|
1704 |
sn_tab = qemu_mallocz(s->nb_snapshots * sizeof(QEMUSnapshotInfo));
|
1705 |
if (!sn_tab)
|
1706 |
goto fail;
|
1707 |
for(i = 0; i < s->nb_snapshots; i++) { |
1708 |
sn_info = sn_tab + i; |
1709 |
sn = s->snapshots + i; |
1710 |
pstrcpy(sn_info->id_str, sizeof(sn_info->id_str),
|
1711 |
sn->id_str); |
1712 |
pstrcpy(sn_info->name, sizeof(sn_info->name),
|
1713 |
sn->name); |
1714 |
sn_info->vm_state_size = sn->vm_state_size; |
1715 |
sn_info->date_sec = sn->date_sec; |
1716 |
sn_info->date_nsec = sn->date_nsec; |
1717 |
sn_info->vm_clock_nsec = sn->vm_clock_nsec; |
1718 |
} |
1719 |
*psn_tab = sn_tab; |
1720 |
return s->nb_snapshots;
|
1721 |
fail:
|
1722 |
qemu_free(sn_tab); |
1723 |
*psn_tab = NULL;
|
1724 |
return -ENOMEM;
|
1725 |
} |
1726 |
|
1727 |
/*********************************************************/
|
1728 |
/* refcount handling */
|
1729 |
|
1730 |
static int refcount_init(BlockDriverState *bs) |
1731 |
{ |
1732 |
BDRVQcowState *s = bs->opaque; |
1733 |
int ret, refcount_table_size2, i;
|
1734 |
|
1735 |
s->refcount_block_cache = qemu_malloc(s->cluster_size); |
1736 |
if (!s->refcount_block_cache)
|
1737 |
goto fail;
|
1738 |
refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t);
|
1739 |
s->refcount_table = qemu_malloc(refcount_table_size2); |
1740 |
if (!s->refcount_table)
|
1741 |
goto fail;
|
1742 |
if (s->refcount_table_size > 0) { |
1743 |
ret = bdrv_pread(s->hd, s->refcount_table_offset, |
1744 |
s->refcount_table, refcount_table_size2); |
1745 |
if (ret != refcount_table_size2)
|
1746 |
goto fail;
|
1747 |
for(i = 0; i < s->refcount_table_size; i++) |
1748 |
be64_to_cpus(&s->refcount_table[i]); |
1749 |
} |
1750 |
return 0; |
1751 |
fail:
|
1752 |
return -ENOMEM;
|
1753 |
} |
1754 |
|
1755 |
static void refcount_close(BlockDriverState *bs) |
1756 |
{ |
1757 |
BDRVQcowState *s = bs->opaque; |
1758 |
qemu_free(s->refcount_block_cache); |
1759 |
qemu_free(s->refcount_table); |
1760 |
} |
1761 |
|
1762 |
|
1763 |
static int load_refcount_block(BlockDriverState *bs, |
1764 |
int64_t refcount_block_offset) |
1765 |
{ |
1766 |
BDRVQcowState *s = bs->opaque; |
1767 |
int ret;
|
1768 |
ret = bdrv_pread(s->hd, refcount_block_offset, s->refcount_block_cache, |
1769 |
s->cluster_size); |
1770 |
if (ret != s->cluster_size)
|
1771 |
return -EIO;
|
1772 |
s->refcount_block_cache_offset = refcount_block_offset; |
1773 |
return 0; |
1774 |
} |
1775 |
|
1776 |
static int get_refcount(BlockDriverState *bs, int64_t cluster_index) |
1777 |
{ |
1778 |
BDRVQcowState *s = bs->opaque; |
1779 |
int refcount_table_index, block_index;
|
1780 |
int64_t refcount_block_offset; |
1781 |
|
1782 |
refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); |
1783 |
if (refcount_table_index >= s->refcount_table_size)
|
1784 |
return 0; |
1785 |
refcount_block_offset = s->refcount_table[refcount_table_index]; |
1786 |
if (!refcount_block_offset)
|
1787 |
return 0; |
1788 |
if (refcount_block_offset != s->refcount_block_cache_offset) {
|
1789 |
/* better than nothing: return allocated if read error */
|
1790 |
if (load_refcount_block(bs, refcount_block_offset) < 0) |
1791 |
return 1; |
1792 |
} |
1793 |
block_index = cluster_index & |
1794 |
((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
1795 |
return be16_to_cpu(s->refcount_block_cache[block_index]);
|
1796 |
} |
1797 |
|
1798 |
/* return < 0 if error */
|
1799 |
static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size)
|
1800 |
{ |
1801 |
BDRVQcowState *s = bs->opaque; |
1802 |
int i, nb_clusters;
|
1803 |
|
1804 |
nb_clusters = (size + s->cluster_size - 1) >> s->cluster_bits;
|
1805 |
for(;;) {
|
1806 |
if (get_refcount(bs, s->free_cluster_index) == 0) { |
1807 |
s->free_cluster_index++; |
1808 |
for(i = 1; i < nb_clusters; i++) { |
1809 |
if (get_refcount(bs, s->free_cluster_index) != 0) |
1810 |
goto not_found;
|
1811 |
s->free_cluster_index++; |
1812 |
} |
1813 |
#ifdef DEBUG_ALLOC2
|
1814 |
printf("alloc_clusters: size=%lld -> %lld\n",
|
1815 |
size, |
1816 |
(s->free_cluster_index - nb_clusters) << s->cluster_bits); |
1817 |
#endif
|
1818 |
return (s->free_cluster_index - nb_clusters) << s->cluster_bits;
|
1819 |
} else {
|
1820 |
not_found:
|
1821 |
s->free_cluster_index++; |
1822 |
} |
1823 |
} |
1824 |
} |
1825 |
|
1826 |
static int64_t alloc_clusters(BlockDriverState *bs, int64_t size)
|
1827 |
{ |
1828 |
int64_t offset; |
1829 |
|
1830 |
offset = alloc_clusters_noref(bs, size); |
1831 |
update_refcount(bs, offset, size, 1);
|
1832 |
return offset;
|
1833 |
} |
1834 |
|
1835 |
/* only used to allocate compressed sectors. We try to allocate
|
1836 |
contiguous sectors. size must be <= cluster_size */
|
1837 |
static int64_t alloc_bytes(BlockDriverState *bs, int size) |
1838 |
{ |
1839 |
BDRVQcowState *s = bs->opaque; |
1840 |
int64_t offset, cluster_offset; |
1841 |
int free_in_cluster;
|
1842 |
|
1843 |
assert(size > 0 && size <= s->cluster_size);
|
1844 |
if (s->free_byte_offset == 0) { |
1845 |
s->free_byte_offset = alloc_clusters(bs, s->cluster_size); |
1846 |
} |
1847 |
redo:
|
1848 |
free_in_cluster = s->cluster_size - |
1849 |
(s->free_byte_offset & (s->cluster_size - 1));
|
1850 |
if (size <= free_in_cluster) {
|
1851 |
/* enough space in current cluster */
|
1852 |
offset = s->free_byte_offset; |
1853 |
s->free_byte_offset += size; |
1854 |
free_in_cluster -= size; |
1855 |
if (free_in_cluster == 0) |
1856 |
s->free_byte_offset = 0;
|
1857 |
if ((offset & (s->cluster_size - 1)) != 0) |
1858 |
update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
|
1859 |
} else {
|
1860 |
offset = alloc_clusters(bs, s->cluster_size); |
1861 |
cluster_offset = s->free_byte_offset & ~(s->cluster_size - 1);
|
1862 |
if ((cluster_offset + s->cluster_size) == offset) {
|
1863 |
/* we are lucky: contiguous data */
|
1864 |
offset = s->free_byte_offset; |
1865 |
update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
|
1866 |
s->free_byte_offset += size; |
1867 |
} else {
|
1868 |
s->free_byte_offset = offset; |
1869 |
goto redo;
|
1870 |
} |
1871 |
} |
1872 |
return offset;
|
1873 |
} |
1874 |
|
1875 |
static void free_clusters(BlockDriverState *bs, |
1876 |
int64_t offset, int64_t size) |
1877 |
{ |
1878 |
update_refcount(bs, offset, size, -1);
|
1879 |
} |
1880 |
|
1881 |
static int grow_refcount_table(BlockDriverState *bs, int min_size) |
1882 |
{ |
1883 |
BDRVQcowState *s = bs->opaque; |
1884 |
int new_table_size, new_table_size2, refcount_table_clusters, i, ret;
|
1885 |
uint64_t *new_table; |
1886 |
int64_t table_offset; |
1887 |
uint64_t data64; |
1888 |
uint32_t data32; |
1889 |
int old_table_size;
|
1890 |
int64_t old_table_offset; |
1891 |
|
1892 |
if (min_size <= s->refcount_table_size)
|
1893 |
return 0; |
1894 |
/* compute new table size */
|
1895 |
refcount_table_clusters = s->refcount_table_size >> (s->cluster_bits - 3);
|
1896 |
for(;;) {
|
1897 |
if (refcount_table_clusters == 0) { |
1898 |
refcount_table_clusters = 1;
|
1899 |
} else {
|
1900 |
refcount_table_clusters = (refcount_table_clusters * 3 + 1) / 2; |
1901 |
} |
1902 |
new_table_size = refcount_table_clusters << (s->cluster_bits - 3);
|
1903 |
if (min_size <= new_table_size)
|
1904 |
break;
|
1905 |
} |
1906 |
#ifdef DEBUG_ALLOC2
|
1907 |
printf("grow_refcount_table from %d to %d\n",
|
1908 |
s->refcount_table_size, |
1909 |
new_table_size); |
1910 |
#endif
|
1911 |
new_table_size2 = new_table_size * sizeof(uint64_t);
|
1912 |
new_table = qemu_mallocz(new_table_size2); |
1913 |
if (!new_table)
|
1914 |
return -ENOMEM;
|
1915 |
memcpy(new_table, s->refcount_table, |
1916 |
s->refcount_table_size * sizeof(uint64_t));
|
1917 |
for(i = 0; i < s->refcount_table_size; i++) |
1918 |
cpu_to_be64s(&new_table[i]); |
1919 |
/* Note: we cannot update the refcount now to avoid recursion */
|
1920 |
table_offset = alloc_clusters_noref(bs, new_table_size2); |
1921 |
ret = bdrv_pwrite(s->hd, table_offset, new_table, new_table_size2); |
1922 |
if (ret != new_table_size2)
|
1923 |
goto fail;
|
1924 |
for(i = 0; i < s->refcount_table_size; i++) |
1925 |
be64_to_cpus(&new_table[i]); |
1926 |
|
1927 |
data64 = cpu_to_be64(table_offset); |
1928 |
if (bdrv_pwrite(s->hd, offsetof(QCowHeader, refcount_table_offset),
|
1929 |
&data64, sizeof(data64)) != sizeof(data64)) |
1930 |
goto fail;
|
1931 |
data32 = cpu_to_be32(refcount_table_clusters); |
1932 |
if (bdrv_pwrite(s->hd, offsetof(QCowHeader, refcount_table_clusters),
|
1933 |
&data32, sizeof(data32)) != sizeof(data32)) |
1934 |
goto fail;
|
1935 |
qemu_free(s->refcount_table); |
1936 |
old_table_offset = s->refcount_table_offset; |
1937 |
old_table_size = s->refcount_table_size; |
1938 |
s->refcount_table = new_table; |
1939 |
s->refcount_table_size = new_table_size; |
1940 |
s->refcount_table_offset = table_offset; |
1941 |
|
1942 |
update_refcount(bs, table_offset, new_table_size2, 1);
|
1943 |
free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t));
|
1944 |
return 0; |
1945 |
fail:
|
1946 |
free_clusters(bs, table_offset, new_table_size2); |
1947 |
qemu_free(new_table); |
1948 |
return -EIO;
|
1949 |
} |
1950 |
|
1951 |
/* addend must be 1 or -1 */
|
1952 |
/* XXX: cache several refcount block clusters ? */
|
1953 |
static int update_cluster_refcount(BlockDriverState *bs, |
1954 |
int64_t cluster_index, |
1955 |
int addend)
|
1956 |
{ |
1957 |
BDRVQcowState *s = bs->opaque; |
1958 |
int64_t offset, refcount_block_offset; |
1959 |
int ret, refcount_table_index, block_index, refcount;
|
1960 |
uint64_t data64; |
1961 |
|
1962 |
refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); |
1963 |
if (refcount_table_index >= s->refcount_table_size) {
|
1964 |
if (addend < 0) |
1965 |
return -EINVAL;
|
1966 |
ret = grow_refcount_table(bs, refcount_table_index + 1);
|
1967 |
if (ret < 0) |
1968 |
return ret;
|
1969 |
} |
1970 |
refcount_block_offset = s->refcount_table[refcount_table_index]; |
1971 |
if (!refcount_block_offset) {
|
1972 |
if (addend < 0) |
1973 |
return -EINVAL;
|
1974 |
/* create a new refcount block */
|
1975 |
/* Note: we cannot update the refcount now to avoid recursion */
|
1976 |
offset = alloc_clusters_noref(bs, s->cluster_size); |
1977 |
memset(s->refcount_block_cache, 0, s->cluster_size);
|
1978 |
ret = bdrv_pwrite(s->hd, offset, s->refcount_block_cache, s->cluster_size); |
1979 |
if (ret != s->cluster_size)
|
1980 |
return -EINVAL;
|
1981 |
s->refcount_table[refcount_table_index] = offset; |
1982 |
data64 = cpu_to_be64(offset); |
1983 |
ret = bdrv_pwrite(s->hd, s->refcount_table_offset + |
1984 |
refcount_table_index * sizeof(uint64_t),
|
1985 |
&data64, sizeof(data64));
|
1986 |
if (ret != sizeof(data64)) |
1987 |
return -EINVAL;
|
1988 |
|
1989 |
refcount_block_offset = offset; |
1990 |
s->refcount_block_cache_offset = offset; |
1991 |
update_refcount(bs, offset, s->cluster_size, 1);
|
1992 |
} else {
|
1993 |
if (refcount_block_offset != s->refcount_block_cache_offset) {
|
1994 |
if (load_refcount_block(bs, refcount_block_offset) < 0) |
1995 |
return -EIO;
|
1996 |
} |
1997 |
} |
1998 |
/* we can update the count and save it */
|
1999 |
block_index = cluster_index & |
2000 |
((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
2001 |
refcount = be16_to_cpu(s->refcount_block_cache[block_index]); |
2002 |
refcount += addend; |
2003 |
if (refcount < 0 || refcount > 0xffff) |
2004 |
return -EINVAL;
|
2005 |
if (refcount == 0 && cluster_index < s->free_cluster_index) { |
2006 |
s->free_cluster_index = cluster_index; |
2007 |
} |
2008 |
s->refcount_block_cache[block_index] = cpu_to_be16(refcount); |
2009 |
if (bdrv_pwrite(s->hd,
|
2010 |
refcount_block_offset + (block_index << REFCOUNT_SHIFT), |
2011 |
&s->refcount_block_cache[block_index], 2) != 2) |
2012 |
return -EIO;
|
2013 |
return refcount;
|
2014 |
} |
2015 |
|
2016 |
static void update_refcount(BlockDriverState *bs, |
2017 |
int64_t offset, int64_t length, |
2018 |
int addend)
|
2019 |
{ |
2020 |
BDRVQcowState *s = bs->opaque; |
2021 |
int64_t start, last, cluster_offset; |
2022 |
|
2023 |
#ifdef DEBUG_ALLOC2
|
2024 |
printf("update_refcount: offset=%lld size=%lld addend=%d\n",
|
2025 |
offset, length, addend); |
2026 |
#endif
|
2027 |
if (length <= 0) |
2028 |
return;
|
2029 |
start = offset & ~(s->cluster_size - 1);
|
2030 |
last = (offset + length - 1) & ~(s->cluster_size - 1); |
2031 |
for(cluster_offset = start; cluster_offset <= last;
|
2032 |
cluster_offset += s->cluster_size) { |
2033 |
update_cluster_refcount(bs, cluster_offset >> s->cluster_bits, addend); |
2034 |
} |
2035 |
} |
2036 |
|
2037 |
#ifdef DEBUG_ALLOC
|
2038 |
static void inc_refcounts(BlockDriverState *bs, |
2039 |
uint16_t *refcount_table, |
2040 |
int refcount_table_size,
|
2041 |
int64_t offset, int64_t size) |
2042 |
{ |
2043 |
BDRVQcowState *s = bs->opaque; |
2044 |
int64_t start, last, cluster_offset; |
2045 |
int k;
|
2046 |
|
2047 |
if (size <= 0) |
2048 |
return;
|
2049 |
|
2050 |
start = offset & ~(s->cluster_size - 1);
|
2051 |
last = (offset + size - 1) & ~(s->cluster_size - 1); |
2052 |
for(cluster_offset = start; cluster_offset <= last;
|
2053 |
cluster_offset += s->cluster_size) { |
2054 |
k = cluster_offset >> s->cluster_bits; |
2055 |
if (k < 0 || k >= refcount_table_size) { |
2056 |
printf("ERROR: invalid cluster offset=0x%llx\n", cluster_offset);
|
2057 |
} else {
|
2058 |
if (++refcount_table[k] == 0) { |
2059 |
printf("ERROR: overflow cluster offset=0x%llx\n", cluster_offset);
|
2060 |
} |
2061 |
} |
2062 |
} |
2063 |
} |
2064 |
|
2065 |
static int check_refcounts_l1(BlockDriverState *bs, |
2066 |
uint16_t *refcount_table, |
2067 |
int refcount_table_size,
|
2068 |
int64_t l1_table_offset, int l1_size,
|
2069 |
int check_copied)
|
2070 |
{ |
2071 |
BDRVQcowState *s = bs->opaque; |
2072 |
uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2; |
2073 |
int l2_size, i, j, nb_csectors, refcount;
|
2074 |
|
2075 |
l2_table = NULL;
|
2076 |
l1_size2 = l1_size * sizeof(uint64_t);
|
2077 |
|
2078 |
inc_refcounts(bs, refcount_table, refcount_table_size, |
2079 |
l1_table_offset, l1_size2); |
2080 |
|
2081 |
l1_table = qemu_malloc(l1_size2); |
2082 |
if (!l1_table)
|
2083 |
goto fail;
|
2084 |
if (bdrv_pread(s->hd, l1_table_offset,
|
2085 |
l1_table, l1_size2) != l1_size2) |
2086 |
goto fail;
|
2087 |
for(i = 0;i < l1_size; i++) |
2088 |
be64_to_cpus(&l1_table[i]); |
2089 |
|
2090 |
l2_size = s->l2_size * sizeof(uint64_t);
|
2091 |
l2_table = qemu_malloc(l2_size); |
2092 |
if (!l2_table)
|
2093 |
goto fail;
|
2094 |
for(i = 0; i < l1_size; i++) { |
2095 |
l2_offset = l1_table[i]; |
2096 |
if (l2_offset) {
|
2097 |
if (check_copied) {
|
2098 |
refcount = get_refcount(bs, (l2_offset & ~QCOW_OFLAG_COPIED) >> s->cluster_bits); |
2099 |
if ((refcount == 1) != ((l2_offset & QCOW_OFLAG_COPIED) != 0)) { |
2100 |
printf("ERROR OFLAG_COPIED: l2_offset=%llx refcount=%d\n",
|
2101 |
l2_offset, refcount); |
2102 |
} |
2103 |
} |
2104 |
l2_offset &= ~QCOW_OFLAG_COPIED; |
2105 |
if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size)
|
2106 |
goto fail;
|
2107 |
for(j = 0; j < s->l2_size; j++) { |
2108 |
offset = be64_to_cpu(l2_table[j]); |
2109 |
if (offset != 0) { |
2110 |
if (offset & QCOW_OFLAG_COMPRESSED) {
|
2111 |
if (offset & QCOW_OFLAG_COPIED) {
|
2112 |
printf("ERROR: cluster %lld: copied flag must never be set for compressed clusters\n",
|
2113 |
offset >> s->cluster_bits); |
2114 |
offset &= ~QCOW_OFLAG_COPIED; |
2115 |
} |
2116 |
nb_csectors = ((offset >> s->csize_shift) & |
2117 |
s->csize_mask) + 1;
|
2118 |
offset &= s->cluster_offset_mask; |
2119 |
inc_refcounts(bs, refcount_table, |
2120 |
refcount_table_size, |
2121 |
offset & ~511, nb_csectors * 512); |
2122 |
} else {
|
2123 |
if (check_copied) {
|
2124 |
refcount = get_refcount(bs, (offset & ~QCOW_OFLAG_COPIED) >> s->cluster_bits); |
2125 |
if ((refcount == 1) != ((offset & QCOW_OFLAG_COPIED) != 0)) { |
2126 |
printf("ERROR OFLAG_COPIED: offset=%llx refcount=%d\n",
|
2127 |
offset, refcount); |
2128 |
} |
2129 |
} |
2130 |
offset &= ~QCOW_OFLAG_COPIED; |
2131 |
inc_refcounts(bs, refcount_table, |
2132 |
refcount_table_size, |
2133 |
offset, s->cluster_size); |
2134 |
} |
2135 |
} |
2136 |
} |
2137 |
inc_refcounts(bs, refcount_table, |
2138 |
refcount_table_size, |
2139 |
l2_offset, |
2140 |
s->cluster_size); |
2141 |
} |
2142 |
} |
2143 |
qemu_free(l1_table); |
2144 |
qemu_free(l2_table); |
2145 |
return 0; |
2146 |
fail:
|
2147 |
printf("ERROR: I/O error in check_refcounts_l1\n");
|
2148 |
qemu_free(l1_table); |
2149 |
qemu_free(l2_table); |
2150 |
return -EIO;
|
2151 |
} |
2152 |
|
2153 |
static void check_refcounts(BlockDriverState *bs) |
2154 |
{ |
2155 |
BDRVQcowState *s = bs->opaque; |
2156 |
int64_t size; |
2157 |
int nb_clusters, refcount1, refcount2, i;
|
2158 |
QCowSnapshot *sn; |
2159 |
uint16_t *refcount_table; |
2160 |
|
2161 |
size = bdrv_getlength(s->hd); |
2162 |
nb_clusters = (size + s->cluster_size - 1) >> s->cluster_bits;
|
2163 |
refcount_table = qemu_mallocz(nb_clusters * sizeof(uint16_t));
|
2164 |
|
2165 |
/* header */
|
2166 |
inc_refcounts(bs, refcount_table, nb_clusters, |
2167 |
0, s->cluster_size);
|
2168 |
|
2169 |
check_refcounts_l1(bs, refcount_table, nb_clusters, |
2170 |
s->l1_table_offset, s->l1_size, 1);
|
2171 |
|
2172 |
/* snapshots */
|
2173 |
for(i = 0; i < s->nb_snapshots; i++) { |
2174 |
sn = s->snapshots + i; |
2175 |
check_refcounts_l1(bs, refcount_table, nb_clusters, |
2176 |
sn->l1_table_offset, sn->l1_size, 0);
|
2177 |
} |
2178 |
inc_refcounts(bs, refcount_table, nb_clusters, |
2179 |
s->snapshots_offset, s->snapshots_size); |
2180 |
|
2181 |
/* refcount data */
|
2182 |
inc_refcounts(bs, refcount_table, nb_clusters, |
2183 |
s->refcount_table_offset, |
2184 |
s->refcount_table_size * sizeof(uint64_t));
|
2185 |
for(i = 0; i < s->refcount_table_size; i++) { |
2186 |
int64_t offset; |
2187 |
offset = s->refcount_table[i]; |
2188 |
if (offset != 0) { |
2189 |
inc_refcounts(bs, refcount_table, nb_clusters, |
2190 |
offset, s->cluster_size); |
2191 |
} |
2192 |
} |
2193 |
|
2194 |
/* compare ref counts */
|
2195 |
for(i = 0; i < nb_clusters; i++) { |
2196 |
refcount1 = get_refcount(bs, i); |
2197 |
refcount2 = refcount_table[i]; |
2198 |
if (refcount1 != refcount2)
|
2199 |
printf("ERROR cluster %d refcount=%d reference=%d\n",
|
2200 |
i, refcount1, refcount2); |
2201 |
} |
2202 |
|
2203 |
qemu_free(refcount_table); |
2204 |
} |
2205 |
|
2206 |
#if 0
|
2207 |
static void dump_refcounts(BlockDriverState *bs)
|
2208 |
{
|
2209 |
BDRVQcowState *s = bs->opaque;
|
2210 |
int64_t nb_clusters, k, k1, size;
|
2211 |
int refcount;
|
2212 |
|
2213 |
size = bdrv_getlength(s->hd);
|
2214 |
nb_clusters = (size + s->cluster_size - 1) >> s->cluster_bits;
|
2215 |
for(k = 0; k < nb_clusters;) {
|
2216 |
k1 = k;
|
2217 |
refcount = get_refcount(bs, k);
|
2218 |
k++;
|
2219 |
while (k < nb_clusters && get_refcount(bs, k) == refcount)
|
2220 |
k++;
|
2221 |
printf("%lld: refcount=%d nb=%lld\n", k, refcount, k - k1);
|
2222 |
}
|
2223 |
}
|
2224 |
#endif
|
2225 |
#endif
|
2226 |
|
2227 |
BlockDriver bdrv_qcow2 = { |
2228 |
"qcow2",
|
2229 |
sizeof(BDRVQcowState),
|
2230 |
qcow_probe, |
2231 |
qcow_open, |
2232 |
NULL,
|
2233 |
NULL,
|
2234 |
qcow_close, |
2235 |
qcow_create, |
2236 |
qcow_flush, |
2237 |
qcow_is_allocated, |
2238 |
qcow_set_key, |
2239 |
qcow_make_empty, |
2240 |
|
2241 |
.bdrv_aio_read = qcow_aio_read, |
2242 |
.bdrv_aio_write = qcow_aio_write, |
2243 |
.bdrv_aio_cancel = qcow_aio_cancel, |
2244 |
.aiocb_size = sizeof(QCowAIOCB),
|
2245 |
.bdrv_write_compressed = qcow_write_compressed, |
2246 |
|
2247 |
.bdrv_snapshot_create = qcow_snapshot_create, |
2248 |
.bdrv_snapshot_goto = qcow_snapshot_goto, |
2249 |
.bdrv_snapshot_delete = qcow_snapshot_delete, |
2250 |
.bdrv_snapshot_list = qcow_snapshot_list, |
2251 |
.bdrv_get_info = qcow_get_info, |
2252 |
}; |