1126 lines
35 KiB
C
1126 lines
35 KiB
C
/*
|
|
* Block driver for the QCOW format
|
|
*
|
|
* Copyright (c) 2004-2006 Fabrice Bellard
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to deal
|
|
* in the Software without restriction, including without limitation the rights
|
|
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
* copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
|
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
|
* THE SOFTWARE.
|
|
*/
|
|
#include "qemu/osdep.h"
|
|
#include "qapi/error.h"
|
|
#include "qemu-common.h"
|
|
#include "qemu/error-report.h"
|
|
#include "block/block_int.h"
|
|
#include "sysemu/block-backend.h"
|
|
#include "qemu/module.h"
|
|
#include "qemu/bswap.h"
|
|
#include <zlib.h>
|
|
#include "qapi/qmp/qerror.h"
|
|
#include "qapi/qmp/qstring.h"
|
|
#include "crypto/block.h"
|
|
#include "migration/blocker.h"
|
|
#include "block/crypto.h"
|
|
|
|
/**************************************************************/
|
|
/* QEMU COW block driver with compression and encryption support */
|
|
|
|
#define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb)
|
|
#define QCOW_VERSION 1
|
|
|
|
#define QCOW_CRYPT_NONE 0
|
|
#define QCOW_CRYPT_AES 1
|
|
|
|
#define QCOW_OFLAG_COMPRESSED (1LL << 63)
|
|
|
|
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;
|
|
uint16_t padding;
|
|
uint32_t crypt_method;
|
|
uint64_t l1_table_offset;
|
|
} QEMU_PACKED QCowHeader;
|
|
|
|
#define L2_CACHE_SIZE 16
|
|
|
|
typedef struct BDRVQcowState {
|
|
int cluster_bits;
|
|
int cluster_size;
|
|
int cluster_sectors;
|
|
int l2_bits;
|
|
int l2_size;
|
|
unsigned int l1_size;
|
|
uint64_t cluster_offset_mask;
|
|
uint64_t l1_table_offset;
|
|
uint64_t *l1_table;
|
|
uint64_t *l2_cache;
|
|
uint64_t l2_cache_offsets[L2_CACHE_SIZE];
|
|
uint32_t l2_cache_counts[L2_CACHE_SIZE];
|
|
uint8_t *cluster_cache;
|
|
uint8_t *cluster_data;
|
|
uint64_t cluster_cache_offset;
|
|
QCryptoBlock *crypto; /* Disk encryption format driver */
|
|
uint32_t crypt_method_header;
|
|
CoMutex lock;
|
|
Error *migration_blocker;
|
|
} BDRVQcowState;
|
|
|
|
static int decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
|
|
|
|
static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename)
|
|
{
|
|
const QCowHeader *cow_header = (const void *)buf;
|
|
|
|
if (buf_size >= sizeof(QCowHeader) &&
|
|
be32_to_cpu(cow_header->magic) == QCOW_MAGIC &&
|
|
be32_to_cpu(cow_header->version) == QCOW_VERSION)
|
|
return 100;
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
static QemuOptsList qcow_runtime_opts = {
|
|
.name = "qcow",
|
|
.head = QTAILQ_HEAD_INITIALIZER(qcow_runtime_opts.head),
|
|
.desc = {
|
|
BLOCK_CRYPTO_OPT_DEF_QCOW_KEY_SECRET("encrypt."),
|
|
{ /* end of list */ }
|
|
},
|
|
};
|
|
|
|
static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
|
|
Error **errp)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
unsigned int len, i, shift;
|
|
int ret;
|
|
QCowHeader header;
|
|
Error *local_err = NULL;
|
|
QCryptoBlockOpenOptions *crypto_opts = NULL;
|
|
unsigned int cflags = 0;
|
|
QDict *encryptopts = NULL;
|
|
const char *encryptfmt;
|
|
|
|
qdict_extract_subqdict(options, &encryptopts, "encrypt.");
|
|
encryptfmt = qdict_get_try_str(encryptopts, "format");
|
|
|
|
bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
|
|
false, errp);
|
|
if (!bs->file) {
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
|
|
ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
be32_to_cpus(&header.magic);
|
|
be32_to_cpus(&header.version);
|
|
be64_to_cpus(&header.backing_file_offset);
|
|
be32_to_cpus(&header.backing_file_size);
|
|
be32_to_cpus(&header.mtime);
|
|
be64_to_cpus(&header.size);
|
|
be32_to_cpus(&header.crypt_method);
|
|
be64_to_cpus(&header.l1_table_offset);
|
|
|
|
if (header.magic != QCOW_MAGIC) {
|
|
error_setg(errp, "Image not in qcow format");
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
if (header.version != QCOW_VERSION) {
|
|
error_setg(errp, "Unsupported qcow version %" PRIu32, header.version);
|
|
ret = -ENOTSUP;
|
|
goto fail;
|
|
}
|
|
|
|
if (header.size <= 1) {
|
|
error_setg(errp, "Image size is too small (must be at least 2 bytes)");
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
if (header.cluster_bits < 9 || header.cluster_bits > 16) {
|
|
error_setg(errp, "Cluster size must be between 512 and 64k");
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
|
|
/* l2_bits specifies number of entries; storing a uint64_t in each entry,
|
|
* so bytes = num_entries << 3. */
|
|
if (header.l2_bits < 9 - 3 || header.l2_bits > 16 - 3) {
|
|
error_setg(errp, "L2 table size must be between 512 and 64k");
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
|
|
s->crypt_method_header = header.crypt_method;
|
|
if (s->crypt_method_header) {
|
|
if (bdrv_uses_whitelist() &&
|
|
s->crypt_method_header == QCOW_CRYPT_AES) {
|
|
error_setg(errp,
|
|
"Use of AES-CBC encrypted qcow images is no longer "
|
|
"supported in system emulators");
|
|
error_append_hint(errp,
|
|
"You can use 'qemu-img convert' to convert your "
|
|
"image to an alternative supported format, such "
|
|
"as unencrypted qcow, or raw with the LUKS "
|
|
"format instead.\n");
|
|
ret = -ENOSYS;
|
|
goto fail;
|
|
}
|
|
if (s->crypt_method_header == QCOW_CRYPT_AES) {
|
|
if (encryptfmt && !g_str_equal(encryptfmt, "aes")) {
|
|
error_setg(errp,
|
|
"Header reported 'aes' encryption format but "
|
|
"options specify '%s'", encryptfmt);
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
qdict_del(encryptopts, "format");
|
|
crypto_opts = block_crypto_open_opts_init(
|
|
Q_CRYPTO_BLOCK_FORMAT_QCOW, encryptopts, errp);
|
|
if (!crypto_opts) {
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
|
|
if (flags & BDRV_O_NO_IO) {
|
|
cflags |= QCRYPTO_BLOCK_OPEN_NO_IO;
|
|
}
|
|
s->crypto = qcrypto_block_open(crypto_opts, "encrypt.",
|
|
NULL, NULL, cflags, errp);
|
|
if (!s->crypto) {
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
} else {
|
|
error_setg(errp, "invalid encryption method in qcow header");
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
bs->encrypted = true;
|
|
} else {
|
|
if (encryptfmt) {
|
|
error_setg(errp, "No encryption in image header, but options "
|
|
"specified format '%s'", encryptfmt);
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
}
|
|
s->cluster_bits = header.cluster_bits;
|
|
s->cluster_size = 1 << s->cluster_bits;
|
|
s->cluster_sectors = 1 << (s->cluster_bits - 9);
|
|
s->l2_bits = header.l2_bits;
|
|
s->l2_size = 1 << s->l2_bits;
|
|
bs->total_sectors = header.size / 512;
|
|
s->cluster_offset_mask = (1LL << (63 - s->cluster_bits)) - 1;
|
|
|
|
/* read the level 1 table */
|
|
shift = s->cluster_bits + s->l2_bits;
|
|
if (header.size > UINT64_MAX - (1LL << shift)) {
|
|
error_setg(errp, "Image too large");
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
} else {
|
|
uint64_t l1_size = (header.size + (1LL << shift) - 1) >> shift;
|
|
if (l1_size > INT_MAX / sizeof(uint64_t)) {
|
|
error_setg(errp, "Image too large");
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
s->l1_size = l1_size;
|
|
}
|
|
|
|
s->l1_table_offset = header.l1_table_offset;
|
|
s->l1_table = g_try_new(uint64_t, s->l1_size);
|
|
if (s->l1_table == NULL) {
|
|
error_setg(errp, "Could not allocate memory for L1 table");
|
|
ret = -ENOMEM;
|
|
goto fail;
|
|
}
|
|
|
|
ret = bdrv_pread(bs->file, s->l1_table_offset, s->l1_table,
|
|
s->l1_size * sizeof(uint64_t));
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
|
|
for(i = 0;i < s->l1_size; i++) {
|
|
be64_to_cpus(&s->l1_table[i]);
|
|
}
|
|
|
|
/* alloc L2 cache (max. 64k * 16 * 8 = 8 MB) */
|
|
s->l2_cache =
|
|
qemu_try_blockalign(bs->file->bs,
|
|
s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t));
|
|
if (s->l2_cache == NULL) {
|
|
error_setg(errp, "Could not allocate L2 table cache");
|
|
ret = -ENOMEM;
|
|
goto fail;
|
|
}
|
|
s->cluster_cache = g_malloc(s->cluster_size);
|
|
s->cluster_data = g_malloc(s->cluster_size);
|
|
s->cluster_cache_offset = -1;
|
|
|
|
/* read the backing file name */
|
|
if (header.backing_file_offset != 0) {
|
|
len = header.backing_file_size;
|
|
if (len > 1023 || len >= sizeof(bs->backing_file)) {
|
|
error_setg(errp, "Backing file name too long");
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
ret = bdrv_pread(bs->file, header.backing_file_offset,
|
|
bs->backing_file, len);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
bs->backing_file[len] = '\0';
|
|
}
|
|
|
|
/* Disable migration when qcow images are used */
|
|
error_setg(&s->migration_blocker, "The qcow format used by node '%s' "
|
|
"does not support live migration",
|
|
bdrv_get_device_or_node_name(bs));
|
|
ret = migrate_add_blocker(s->migration_blocker, &local_err);
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
error_free(s->migration_blocker);
|
|
goto fail;
|
|
}
|
|
|
|
QDECREF(encryptopts);
|
|
qapi_free_QCryptoBlockOpenOptions(crypto_opts);
|
|
qemu_co_mutex_init(&s->lock);
|
|
return 0;
|
|
|
|
fail:
|
|
g_free(s->l1_table);
|
|
qemu_vfree(s->l2_cache);
|
|
g_free(s->cluster_cache);
|
|
g_free(s->cluster_data);
|
|
qcrypto_block_free(s->crypto);
|
|
QDECREF(encryptopts);
|
|
qapi_free_QCryptoBlockOpenOptions(crypto_opts);
|
|
return ret;
|
|
}
|
|
|
|
|
|
/* We have nothing to do for QCOW reopen, stubs just return
|
|
* success */
|
|
static int qcow_reopen_prepare(BDRVReopenState *state,
|
|
BlockReopenQueue *queue, Error **errp)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* 'allocate' is:
|
|
*
|
|
* 0 to not allocate.
|
|
*
|
|
* 1 to allocate a normal cluster (for sector indexes 'n_start' to
|
|
* 'n_end')
|
|
*
|
|
* 2 to allocate a compressed cluster of size
|
|
* 'compressed_size'. 'compressed_size' must be > 0 and <
|
|
* cluster_size
|
|
*
|
|
* return 0 if not allocated, 1 if *result is assigned, and negative
|
|
* errno on failure.
|
|
*/
|
|
static int get_cluster_offset(BlockDriverState *bs,
|
|
uint64_t offset, int allocate,
|
|
int compressed_size,
|
|
int n_start, int n_end, uint64_t *result)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
int min_index, i, j, l1_index, l2_index, ret;
|
|
int64_t l2_offset;
|
|
uint64_t *l2_table, cluster_offset, tmp;
|
|
uint32_t min_count;
|
|
int new_l2_table;
|
|
|
|
*result = 0;
|
|
l1_index = offset >> (s->l2_bits + s->cluster_bits);
|
|
l2_offset = s->l1_table[l1_index];
|
|
new_l2_table = 0;
|
|
if (!l2_offset) {
|
|
if (!allocate)
|
|
return 0;
|
|
/* allocate a new l2 entry */
|
|
l2_offset = bdrv_getlength(bs->file->bs);
|
|
if (l2_offset < 0) {
|
|
return l2_offset;
|
|
}
|
|
/* round to cluster size */
|
|
l2_offset = QEMU_ALIGN_UP(l2_offset, s->cluster_size);
|
|
/* update the L1 entry */
|
|
s->l1_table[l1_index] = l2_offset;
|
|
tmp = cpu_to_be64(l2_offset);
|
|
ret = bdrv_pwrite_sync(bs->file,
|
|
s->l1_table_offset + l1_index * sizeof(tmp),
|
|
&tmp, sizeof(tmp));
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
new_l2_table = 1;
|
|
}
|
|
for(i = 0; i < L2_CACHE_SIZE; i++) {
|
|
if (l2_offset == s->l2_cache_offsets[i]) {
|
|
/* increment the hit count */
|
|
if (++s->l2_cache_counts[i] == 0xffffffff) {
|
|
for(j = 0; j < L2_CACHE_SIZE; j++) {
|
|
s->l2_cache_counts[j] >>= 1;
|
|
}
|
|
}
|
|
l2_table = s->l2_cache + (i << s->l2_bits);
|
|
goto found;
|
|
}
|
|
}
|
|
/* not found: load a new entry in the least used one */
|
|
min_index = 0;
|
|
min_count = 0xffffffff;
|
|
for(i = 0; i < L2_CACHE_SIZE; i++) {
|
|
if (s->l2_cache_counts[i] < min_count) {
|
|
min_count = s->l2_cache_counts[i];
|
|
min_index = i;
|
|
}
|
|
}
|
|
l2_table = s->l2_cache + (min_index << s->l2_bits);
|
|
if (new_l2_table) {
|
|
memset(l2_table, 0, s->l2_size * sizeof(uint64_t));
|
|
ret = bdrv_pwrite_sync(bs->file, l2_offset, l2_table,
|
|
s->l2_size * sizeof(uint64_t));
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
} else {
|
|
ret = bdrv_pread(bs->file, l2_offset, l2_table,
|
|
s->l2_size * sizeof(uint64_t));
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
}
|
|
s->l2_cache_offsets[min_index] = l2_offset;
|
|
s->l2_cache_counts[min_index] = 1;
|
|
found:
|
|
l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
|
|
cluster_offset = be64_to_cpu(l2_table[l2_index]);
|
|
if (!cluster_offset ||
|
|
((cluster_offset & QCOW_OFLAG_COMPRESSED) && allocate == 1)) {
|
|
if (!allocate)
|
|
return 0;
|
|
/* allocate a new cluster */
|
|
if ((cluster_offset & QCOW_OFLAG_COMPRESSED) &&
|
|
(n_end - n_start) < s->cluster_sectors) {
|
|
/* if the cluster is already compressed, we must
|
|
decompress it in the case it is not completely
|
|
overwritten */
|
|
if (decompress_cluster(bs, cluster_offset) < 0) {
|
|
return -EIO;
|
|
}
|
|
cluster_offset = bdrv_getlength(bs->file->bs);
|
|
if ((int64_t) cluster_offset < 0) {
|
|
return cluster_offset;
|
|
}
|
|
cluster_offset = QEMU_ALIGN_UP(cluster_offset, s->cluster_size);
|
|
/* write the cluster content */
|
|
ret = bdrv_pwrite(bs->file, cluster_offset, s->cluster_cache,
|
|
s->cluster_size);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
} else {
|
|
cluster_offset = bdrv_getlength(bs->file->bs);
|
|
if ((int64_t) cluster_offset < 0) {
|
|
return cluster_offset;
|
|
}
|
|
if (allocate == 1) {
|
|
/* round to cluster size */
|
|
cluster_offset = QEMU_ALIGN_UP(cluster_offset, s->cluster_size);
|
|
if (cluster_offset + s->cluster_size > INT64_MAX) {
|
|
return -E2BIG;
|
|
}
|
|
ret = bdrv_truncate(bs->file, cluster_offset + s->cluster_size,
|
|
PREALLOC_MODE_OFF, NULL);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
/* if encrypted, we must initialize the cluster
|
|
content which won't be written */
|
|
if (bs->encrypted &&
|
|
(n_end - n_start) < s->cluster_sectors) {
|
|
uint64_t start_sect;
|
|
assert(s->crypto);
|
|
start_sect = (offset & ~(s->cluster_size - 1)) >> 9;
|
|
for(i = 0; i < s->cluster_sectors; i++) {
|
|
if (i < n_start || i >= n_end) {
|
|
memset(s->cluster_data, 0x00, 512);
|
|
if (qcrypto_block_encrypt(s->crypto, start_sect + i,
|
|
s->cluster_data,
|
|
BDRV_SECTOR_SIZE,
|
|
NULL) < 0) {
|
|
return -EIO;
|
|
}
|
|
ret = bdrv_pwrite(bs->file,
|
|
cluster_offset + i * 512,
|
|
s->cluster_data, 512);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
} else if (allocate == 2) {
|
|
cluster_offset |= QCOW_OFLAG_COMPRESSED |
|
|
(uint64_t)compressed_size << (63 - s->cluster_bits);
|
|
}
|
|
}
|
|
/* update L2 table */
|
|
tmp = cpu_to_be64(cluster_offset);
|
|
l2_table[l2_index] = tmp;
|
|
ret = bdrv_pwrite_sync(bs->file, l2_offset + l2_index * sizeof(tmp),
|
|
&tmp, sizeof(tmp));
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
}
|
|
*result = cluster_offset;
|
|
return 1;
|
|
}
|
|
|
|
static int64_t coroutine_fn qcow_co_get_block_status(BlockDriverState *bs,
|
|
int64_t sector_num, int nb_sectors, int *pnum, BlockDriverState **file)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
int index_in_cluster, n, ret;
|
|
uint64_t cluster_offset;
|
|
|
|
qemu_co_mutex_lock(&s->lock);
|
|
ret = get_cluster_offset(bs, sector_num << 9, 0, 0, 0, 0, &cluster_offset);
|
|
qemu_co_mutex_unlock(&s->lock);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
index_in_cluster = sector_num & (s->cluster_sectors - 1);
|
|
n = s->cluster_sectors - index_in_cluster;
|
|
if (n > nb_sectors)
|
|
n = nb_sectors;
|
|
*pnum = n;
|
|
if (!cluster_offset) {
|
|
return 0;
|
|
}
|
|
if ((cluster_offset & QCOW_OFLAG_COMPRESSED) || s->crypto) {
|
|
return BDRV_BLOCK_DATA;
|
|
}
|
|
cluster_offset |= (index_in_cluster << BDRV_SECTOR_BITS);
|
|
*file = bs->file->bs;
|
|
return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID | cluster_offset;
|
|
}
|
|
|
|
static int decompress_buffer(uint8_t *out_buf, int out_buf_size,
|
|
const uint8_t *buf, int buf_size)
|
|
{
|
|
z_stream strm1, *strm = &strm1;
|
|
int ret, out_len;
|
|
|
|
memset(strm, 0, sizeof(*strm));
|
|
|
|
strm->next_in = (uint8_t *)buf;
|
|
strm->avail_in = buf_size;
|
|
strm->next_out = out_buf;
|
|
strm->avail_out = out_buf_size;
|
|
|
|
ret = inflateInit2(strm, -12);
|
|
if (ret != Z_OK)
|
|
return -1;
|
|
ret = inflate(strm, Z_FINISH);
|
|
out_len = strm->next_out - out_buf;
|
|
if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) ||
|
|
out_len != out_buf_size) {
|
|
inflateEnd(strm);
|
|
return -1;
|
|
}
|
|
inflateEnd(strm);
|
|
return 0;
|
|
}
|
|
|
|
static int decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
int ret, csize;
|
|
uint64_t coffset;
|
|
|
|
coffset = cluster_offset & s->cluster_offset_mask;
|
|
if (s->cluster_cache_offset != coffset) {
|
|
csize = cluster_offset >> (63 - s->cluster_bits);
|
|
csize &= (s->cluster_size - 1);
|
|
ret = bdrv_pread(bs->file, coffset, s->cluster_data, csize);
|
|
if (ret != csize)
|
|
return -1;
|
|
if (decompress_buffer(s->cluster_cache, s->cluster_size,
|
|
s->cluster_data, csize) < 0) {
|
|
return -1;
|
|
}
|
|
s->cluster_cache_offset = coffset;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static coroutine_fn int qcow_co_readv(BlockDriverState *bs, int64_t sector_num,
|
|
int nb_sectors, QEMUIOVector *qiov)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
int index_in_cluster;
|
|
int ret = 0, n;
|
|
uint64_t cluster_offset;
|
|
struct iovec hd_iov;
|
|
QEMUIOVector hd_qiov;
|
|
uint8_t *buf;
|
|
void *orig_buf;
|
|
|
|
if (qiov->niov > 1) {
|
|
buf = orig_buf = qemu_try_blockalign(bs, qiov->size);
|
|
if (buf == NULL) {
|
|
return -ENOMEM;
|
|
}
|
|
} else {
|
|
orig_buf = NULL;
|
|
buf = (uint8_t *)qiov->iov->iov_base;
|
|
}
|
|
|
|
qemu_co_mutex_lock(&s->lock);
|
|
|
|
while (nb_sectors != 0) {
|
|
/* prepare next request */
|
|
ret = get_cluster_offset(bs, sector_num << 9,
|
|
0, 0, 0, 0, &cluster_offset);
|
|
if (ret < 0) {
|
|
break;
|
|
}
|
|
index_in_cluster = sector_num & (s->cluster_sectors - 1);
|
|
n = s->cluster_sectors - index_in_cluster;
|
|
if (n > nb_sectors) {
|
|
n = nb_sectors;
|
|
}
|
|
|
|
if (!cluster_offset) {
|
|
if (bs->backing) {
|
|
/* read from the base image */
|
|
hd_iov.iov_base = (void *)buf;
|
|
hd_iov.iov_len = n * 512;
|
|
qemu_iovec_init_external(&hd_qiov, &hd_iov, 1);
|
|
qemu_co_mutex_unlock(&s->lock);
|
|
ret = bdrv_co_readv(bs->backing, sector_num, n, &hd_qiov);
|
|
qemu_co_mutex_lock(&s->lock);
|
|
if (ret < 0) {
|
|
break;
|
|
}
|
|
} else {
|
|
/* Note: in this case, no need to wait */
|
|
memset(buf, 0, 512 * n);
|
|
}
|
|
} else if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
|
|
/* add AIO support for compressed blocks ? */
|
|
if (decompress_cluster(bs, cluster_offset) < 0) {
|
|
ret = -EIO;
|
|
break;
|
|
}
|
|
memcpy(buf,
|
|
s->cluster_cache + index_in_cluster * 512, 512 * n);
|
|
} else {
|
|
if ((cluster_offset & 511) != 0) {
|
|
ret = -EIO;
|
|
break;
|
|
}
|
|
hd_iov.iov_base = (void *)buf;
|
|
hd_iov.iov_len = n * 512;
|
|
qemu_iovec_init_external(&hd_qiov, &hd_iov, 1);
|
|
qemu_co_mutex_unlock(&s->lock);
|
|
ret = bdrv_co_readv(bs->file,
|
|
(cluster_offset >> 9) + index_in_cluster,
|
|
n, &hd_qiov);
|
|
qemu_co_mutex_lock(&s->lock);
|
|
if (ret < 0) {
|
|
break;
|
|
}
|
|
if (bs->encrypted) {
|
|
assert(s->crypto);
|
|
if (qcrypto_block_decrypt(s->crypto, sector_num, buf,
|
|
n * BDRV_SECTOR_SIZE, NULL) < 0) {
|
|
ret = -EIO;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
ret = 0;
|
|
|
|
nb_sectors -= n;
|
|
sector_num += n;
|
|
buf += n * 512;
|
|
}
|
|
|
|
qemu_co_mutex_unlock(&s->lock);
|
|
|
|
if (qiov->niov > 1) {
|
|
qemu_iovec_from_buf(qiov, 0, orig_buf, qiov->size);
|
|
qemu_vfree(orig_buf);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static coroutine_fn int qcow_co_writev(BlockDriverState *bs, int64_t sector_num,
|
|
int nb_sectors, QEMUIOVector *qiov)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
int index_in_cluster;
|
|
uint64_t cluster_offset;
|
|
int ret = 0, n;
|
|
struct iovec hd_iov;
|
|
QEMUIOVector hd_qiov;
|
|
uint8_t *buf;
|
|
void *orig_buf;
|
|
|
|
s->cluster_cache_offset = -1; /* disable compressed cache */
|
|
|
|
/* We must always copy the iov when encrypting, so we
|
|
* don't modify the original data buffer during encryption */
|
|
if (bs->encrypted || qiov->niov > 1) {
|
|
buf = orig_buf = qemu_try_blockalign(bs, qiov->size);
|
|
if (buf == NULL) {
|
|
return -ENOMEM;
|
|
}
|
|
qemu_iovec_to_buf(qiov, 0, buf, qiov->size);
|
|
} else {
|
|
orig_buf = NULL;
|
|
buf = (uint8_t *)qiov->iov->iov_base;
|
|
}
|
|
|
|
qemu_co_mutex_lock(&s->lock);
|
|
|
|
while (nb_sectors != 0) {
|
|
|
|
index_in_cluster = sector_num & (s->cluster_sectors - 1);
|
|
n = s->cluster_sectors - index_in_cluster;
|
|
if (n > nb_sectors) {
|
|
n = nb_sectors;
|
|
}
|
|
ret = get_cluster_offset(bs, sector_num << 9, 1, 0,
|
|
index_in_cluster,
|
|
index_in_cluster + n, &cluster_offset);
|
|
if (ret < 0) {
|
|
break;
|
|
}
|
|
if (!cluster_offset || (cluster_offset & 511) != 0) {
|
|
ret = -EIO;
|
|
break;
|
|
}
|
|
if (bs->encrypted) {
|
|
assert(s->crypto);
|
|
if (qcrypto_block_encrypt(s->crypto, sector_num, buf,
|
|
n * BDRV_SECTOR_SIZE, NULL) < 0) {
|
|
ret = -EIO;
|
|
break;
|
|
}
|
|
}
|
|
|
|
hd_iov.iov_base = (void *)buf;
|
|
hd_iov.iov_len = n * 512;
|
|
qemu_iovec_init_external(&hd_qiov, &hd_iov, 1);
|
|
qemu_co_mutex_unlock(&s->lock);
|
|
ret = bdrv_co_writev(bs->file,
|
|
(cluster_offset >> 9) + index_in_cluster,
|
|
n, &hd_qiov);
|
|
qemu_co_mutex_lock(&s->lock);
|
|
if (ret < 0) {
|
|
break;
|
|
}
|
|
ret = 0;
|
|
|
|
nb_sectors -= n;
|
|
sector_num += n;
|
|
buf += n * 512;
|
|
}
|
|
qemu_co_mutex_unlock(&s->lock);
|
|
|
|
qemu_vfree(orig_buf);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void qcow_close(BlockDriverState *bs)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
|
|
qcrypto_block_free(s->crypto);
|
|
s->crypto = NULL;
|
|
g_free(s->l1_table);
|
|
qemu_vfree(s->l2_cache);
|
|
g_free(s->cluster_cache);
|
|
g_free(s->cluster_data);
|
|
|
|
migrate_del_blocker(s->migration_blocker);
|
|
error_free(s->migration_blocker);
|
|
}
|
|
|
|
static int qcow_create(const char *filename, QemuOpts *opts, Error **errp)
|
|
{
|
|
int header_size, backing_filename_len, l1_size, shift, i;
|
|
QCowHeader header;
|
|
uint8_t *tmp;
|
|
int64_t total_size = 0;
|
|
char *backing_file = NULL;
|
|
Error *local_err = NULL;
|
|
int ret;
|
|
BlockBackend *qcow_blk;
|
|
char *encryptfmt = NULL;
|
|
QDict *options;
|
|
QDict *encryptopts = NULL;
|
|
QCryptoBlockCreateOptions *crypto_opts = NULL;
|
|
QCryptoBlock *crypto = NULL;
|
|
|
|
/* Read out options */
|
|
total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
|
|
BDRV_SECTOR_SIZE);
|
|
if (total_size == 0) {
|
|
error_setg(errp, "Image size is too small, cannot be zero length");
|
|
ret = -EINVAL;
|
|
goto cleanup;
|
|
}
|
|
|
|
backing_file = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FILE);
|
|
encryptfmt = qemu_opt_get_del(opts, BLOCK_OPT_ENCRYPT_FORMAT);
|
|
if (encryptfmt) {
|
|
if (qemu_opt_get(opts, BLOCK_OPT_ENCRYPT)) {
|
|
error_setg(errp, "Options " BLOCK_OPT_ENCRYPT " and "
|
|
BLOCK_OPT_ENCRYPT_FORMAT " are mutually exclusive");
|
|
ret = -EINVAL;
|
|
goto cleanup;
|
|
}
|
|
} else if (qemu_opt_get_bool_del(opts, BLOCK_OPT_ENCRYPT, false)) {
|
|
encryptfmt = g_strdup("aes");
|
|
}
|
|
|
|
ret = bdrv_create_file(filename, opts, &local_err);
|
|
if (ret < 0) {
|
|
error_propagate(errp, local_err);
|
|
goto cleanup;
|
|
}
|
|
|
|
qcow_blk = blk_new_open(filename, NULL, NULL,
|
|
BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL,
|
|
&local_err);
|
|
if (qcow_blk == NULL) {
|
|
error_propagate(errp, local_err);
|
|
ret = -EIO;
|
|
goto cleanup;
|
|
}
|
|
|
|
blk_set_allow_write_beyond_eof(qcow_blk, true);
|
|
|
|
ret = blk_truncate(qcow_blk, 0, PREALLOC_MODE_OFF, errp);
|
|
if (ret < 0) {
|
|
goto exit;
|
|
}
|
|
|
|
memset(&header, 0, sizeof(header));
|
|
header.magic = cpu_to_be32(QCOW_MAGIC);
|
|
header.version = cpu_to_be32(QCOW_VERSION);
|
|
header.size = cpu_to_be64(total_size);
|
|
header_size = sizeof(header);
|
|
backing_filename_len = 0;
|
|
if (backing_file) {
|
|
if (strcmp(backing_file, "fat:")) {
|
|
header.backing_file_offset = cpu_to_be64(header_size);
|
|
backing_filename_len = strlen(backing_file);
|
|
header.backing_file_size = cpu_to_be32(backing_filename_len);
|
|
header_size += backing_filename_len;
|
|
} else {
|
|
/* special backing file for vvfat */
|
|
g_free(backing_file);
|
|
backing_file = NULL;
|
|
}
|
|
header.cluster_bits = 9; /* 512 byte cluster to avoid copying
|
|
unmodified sectors */
|
|
header.l2_bits = 12; /* 32 KB L2 tables */
|
|
} else {
|
|
header.cluster_bits = 12; /* 4 KB clusters */
|
|
header.l2_bits = 9; /* 4 KB L2 tables */
|
|
}
|
|
header_size = (header_size + 7) & ~7;
|
|
shift = header.cluster_bits + header.l2_bits;
|
|
l1_size = (total_size + (1LL << shift) - 1) >> shift;
|
|
|
|
header.l1_table_offset = cpu_to_be64(header_size);
|
|
|
|
options = qemu_opts_to_qdict(opts, NULL);
|
|
qdict_extract_subqdict(options, &encryptopts, "encrypt.");
|
|
QDECREF(options);
|
|
if (encryptfmt) {
|
|
if (!g_str_equal(encryptfmt, "aes")) {
|
|
error_setg(errp, "Unknown encryption format '%s', expected 'aes'",
|
|
encryptfmt);
|
|
ret = -EINVAL;
|
|
goto exit;
|
|
}
|
|
header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES);
|
|
|
|
crypto_opts = block_crypto_create_opts_init(
|
|
Q_CRYPTO_BLOCK_FORMAT_QCOW, encryptopts, errp);
|
|
if (!crypto_opts) {
|
|
ret = -EINVAL;
|
|
goto exit;
|
|
}
|
|
|
|
crypto = qcrypto_block_create(crypto_opts, "encrypt.",
|
|
NULL, NULL, NULL, errp);
|
|
if (!crypto) {
|
|
ret = -EINVAL;
|
|
goto exit;
|
|
}
|
|
} else {
|
|
header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE);
|
|
}
|
|
|
|
/* write all the data */
|
|
ret = blk_pwrite(qcow_blk, 0, &header, sizeof(header), 0);
|
|
if (ret != sizeof(header)) {
|
|
goto exit;
|
|
}
|
|
|
|
if (backing_file) {
|
|
ret = blk_pwrite(qcow_blk, sizeof(header),
|
|
backing_file, backing_filename_len, 0);
|
|
if (ret != backing_filename_len) {
|
|
goto exit;
|
|
}
|
|
}
|
|
|
|
tmp = g_malloc0(BDRV_SECTOR_SIZE);
|
|
for (i = 0; i < DIV_ROUND_UP(sizeof(uint64_t) * l1_size, BDRV_SECTOR_SIZE);
|
|
i++) {
|
|
ret = blk_pwrite(qcow_blk, header_size + BDRV_SECTOR_SIZE * i,
|
|
tmp, BDRV_SECTOR_SIZE, 0);
|
|
if (ret != BDRV_SECTOR_SIZE) {
|
|
g_free(tmp);
|
|
goto exit;
|
|
}
|
|
}
|
|
|
|
g_free(tmp);
|
|
ret = 0;
|
|
exit:
|
|
blk_unref(qcow_blk);
|
|
cleanup:
|
|
QDECREF(encryptopts);
|
|
g_free(encryptfmt);
|
|
qcrypto_block_free(crypto);
|
|
qapi_free_QCryptoBlockCreateOptions(crypto_opts);
|
|
g_free(backing_file);
|
|
return ret;
|
|
}
|
|
|
|
static int qcow_make_empty(BlockDriverState *bs)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
uint32_t l1_length = s->l1_size * sizeof(uint64_t);
|
|
int ret;
|
|
|
|
memset(s->l1_table, 0, l1_length);
|
|
if (bdrv_pwrite_sync(bs->file, s->l1_table_offset, s->l1_table,
|
|
l1_length) < 0)
|
|
return -1;
|
|
ret = bdrv_truncate(bs->file, s->l1_table_offset + l1_length,
|
|
PREALLOC_MODE_OFF, NULL);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
memset(s->l2_cache, 0, s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t));
|
|
memset(s->l2_cache_offsets, 0, L2_CACHE_SIZE * sizeof(uint64_t));
|
|
memset(s->l2_cache_counts, 0, L2_CACHE_SIZE * sizeof(uint32_t));
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* XXX: put compressed sectors first, then all the cluster aligned
|
|
tables to avoid losing bytes in alignment */
|
|
static coroutine_fn int
|
|
qcow_co_pwritev_compressed(BlockDriverState *bs, uint64_t offset,
|
|
uint64_t bytes, QEMUIOVector *qiov)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
QEMUIOVector hd_qiov;
|
|
struct iovec iov;
|
|
z_stream strm;
|
|
int ret, out_len;
|
|
uint8_t *buf, *out_buf;
|
|
uint64_t cluster_offset;
|
|
|
|
buf = qemu_blockalign(bs, s->cluster_size);
|
|
if (bytes != s->cluster_size) {
|
|
if (bytes > s->cluster_size ||
|
|
offset + bytes != bs->total_sectors << BDRV_SECTOR_BITS)
|
|
{
|
|
qemu_vfree(buf);
|
|
return -EINVAL;
|
|
}
|
|
/* Zero-pad last write if image size is not cluster aligned */
|
|
memset(buf + bytes, 0, s->cluster_size - bytes);
|
|
}
|
|
qemu_iovec_to_buf(qiov, 0, buf, qiov->size);
|
|
|
|
out_buf = g_malloc(s->cluster_size);
|
|
|
|
/* best compression, small window, no zlib header */
|
|
memset(&strm, 0, sizeof(strm));
|
|
ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION,
|
|
Z_DEFLATED, -12,
|
|
9, Z_DEFAULT_STRATEGY);
|
|
if (ret != 0) {
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
|
|
strm.avail_in = s->cluster_size;
|
|
strm.next_in = (uint8_t *)buf;
|
|
strm.avail_out = s->cluster_size;
|
|
strm.next_out = out_buf;
|
|
|
|
ret = deflate(&strm, Z_FINISH);
|
|
if (ret != Z_STREAM_END && ret != Z_OK) {
|
|
deflateEnd(&strm);
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
out_len = strm.next_out - out_buf;
|
|
|
|
deflateEnd(&strm);
|
|
|
|
if (ret != Z_STREAM_END || out_len >= s->cluster_size) {
|
|
/* could not compress: write normal cluster */
|
|
ret = qcow_co_writev(bs, offset >> BDRV_SECTOR_BITS,
|
|
bytes >> BDRV_SECTOR_BITS, qiov);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
goto success;
|
|
}
|
|
qemu_co_mutex_lock(&s->lock);
|
|
ret = get_cluster_offset(bs, offset, 2, out_len, 0, 0, &cluster_offset);
|
|
qemu_co_mutex_unlock(&s->lock);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
if (cluster_offset == 0) {
|
|
ret = -EIO;
|
|
goto fail;
|
|
}
|
|
cluster_offset &= s->cluster_offset_mask;
|
|
|
|
iov = (struct iovec) {
|
|
.iov_base = out_buf,
|
|
.iov_len = out_len,
|
|
};
|
|
qemu_iovec_init_external(&hd_qiov, &iov, 1);
|
|
ret = bdrv_co_pwritev(bs->file, cluster_offset, out_len, &hd_qiov, 0);
|
|
if (ret < 0) {
|
|
goto fail;
|
|
}
|
|
success:
|
|
ret = 0;
|
|
fail:
|
|
qemu_vfree(buf);
|
|
g_free(out_buf);
|
|
return ret;
|
|
}
|
|
|
|
static int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
|
|
{
|
|
BDRVQcowState *s = bs->opaque;
|
|
bdi->cluster_size = s->cluster_size;
|
|
return 0;
|
|
}
|
|
|
|
static QemuOptsList qcow_create_opts = {
|
|
.name = "qcow-create-opts",
|
|
.head = QTAILQ_HEAD_INITIALIZER(qcow_create_opts.head),
|
|
.desc = {
|
|
{
|
|
.name = BLOCK_OPT_SIZE,
|
|
.type = QEMU_OPT_SIZE,
|
|
.help = "Virtual disk size"
|
|
},
|
|
{
|
|
.name = BLOCK_OPT_BACKING_FILE,
|
|
.type = QEMU_OPT_STRING,
|
|
.help = "File name of a base image"
|
|
},
|
|
{
|
|
.name = BLOCK_OPT_ENCRYPT,
|
|
.type = QEMU_OPT_BOOL,
|
|
.help = "Encrypt the image with format 'aes'. (Deprecated "
|
|
"in favor of " BLOCK_OPT_ENCRYPT_FORMAT "=aes)",
|
|
},
|
|
{
|
|
.name = BLOCK_OPT_ENCRYPT_FORMAT,
|
|
.type = QEMU_OPT_STRING,
|
|
.help = "Encrypt the image, format choices: 'aes'",
|
|
},
|
|
BLOCK_CRYPTO_OPT_DEF_QCOW_KEY_SECRET("encrypt."),
|
|
{ /* end of list */ }
|
|
}
|
|
};
|
|
|
|
static BlockDriver bdrv_qcow = {
|
|
.format_name = "qcow",
|
|
.instance_size = sizeof(BDRVQcowState),
|
|
.bdrv_probe = qcow_probe,
|
|
.bdrv_open = qcow_open,
|
|
.bdrv_close = qcow_close,
|
|
.bdrv_child_perm = bdrv_format_default_perms,
|
|
.bdrv_reopen_prepare = qcow_reopen_prepare,
|
|
.bdrv_create = qcow_create,
|
|
.bdrv_has_zero_init = bdrv_has_zero_init_1,
|
|
.supports_backing = true,
|
|
|
|
.bdrv_co_readv = qcow_co_readv,
|
|
.bdrv_co_writev = qcow_co_writev,
|
|
.bdrv_co_get_block_status = qcow_co_get_block_status,
|
|
|
|
.bdrv_make_empty = qcow_make_empty,
|
|
.bdrv_co_pwritev_compressed = qcow_co_pwritev_compressed,
|
|
.bdrv_get_info = qcow_get_info,
|
|
|
|
.create_opts = &qcow_create_opts,
|
|
};
|
|
|
|
static void bdrv_qcow_init(void)
|
|
{
|
|
bdrv_register(&bdrv_qcow);
|
|
}
|
|
|
|
block_init(bdrv_qcow_init);
|