#define QCOW2_EXT_MAGIC_CRYPTO_HEADER 0x0537be77
#define QCOW2_EXT_MAGIC_BITMAPS 0x23852875
+static int coroutine_fn
+qcow2_co_preadv_compressed(BlockDriverState *bs,
+ uint64_t file_cluster_offset,
+ uint64_t offset,
+ uint64_t bytes,
+ QEMUIOVector *qiov);
+
static int qcow2_probe(const uint8_t *buf, int buf_size, const char *filename)
{
const QCowHeader *cow_header = (const void *)buf;
"pread fail from offset %" PRIu64, offset);
return 1;
}
- be32_to_cpus(&ext.magic);
- be32_to_cpus(&ext.len);
+ ext.magic = be32_to_cpu(ext.magic);
+ ext.len = be32_to_cpu(ext.len);
offset += sizeof(ext);
#ifdef DEBUG_EXT
printf("ext.magic = 0x%x\n", ext.magic);
"Unable to read CRYPTO header extension");
return ret;
}
- be64_to_cpus(&s->crypto_header.offset);
- be64_to_cpus(&s->crypto_header.length);
+ s->crypto_header.offset = be64_to_cpu(s->crypto_header.offset);
+ s->crypto_header.length = be64_to_cpu(s->crypto_header.length);
if ((s->crypto_header.offset % s->cluster_size) != 0) {
error_setg(errp, "Encryption header offset '%" PRIu64 "' is "
}
s->crypto = qcrypto_block_open(s->crypto_opts, "encrypt.",
qcow2_crypto_hdr_read_func,
- bs, cflags, errp);
+ bs, cflags, 1, errp);
if (!s->crypto) {
return -EINVAL;
}
return -EINVAL;
}
- be32_to_cpus(&bitmaps_ext.nb_bitmaps);
- be64_to_cpus(&bitmaps_ext.bitmap_directory_size);
- be64_to_cpus(&bitmaps_ext.bitmap_directory_offset);
+ bitmaps_ext.nb_bitmaps = be32_to_cpu(bitmaps_ext.nb_bitmaps);
+ bitmaps_ext.bitmap_directory_size =
+ be64_to_cpu(bitmaps_ext.bitmap_directory_size);
+ bitmaps_ext.bitmap_directory_offset =
+ be64_to_cpu(bitmaps_ext.bitmap_directory_offset);
if (bitmaps_ext.nb_bitmaps > QCOW2_MAX_BITMAPS) {
error_setg(errp,
uint64_t *refcount_cache_size, Error **errp)
{
BDRVQcow2State *s = bs->opaque;
- uint64_t combined_cache_size;
+ uint64_t combined_cache_size, l2_cache_max_setting;
bool l2_cache_size_set, refcount_cache_size_set, combined_cache_size_set;
int min_refcount_cache = MIN_REFCOUNT_CACHE_SIZE * s->cluster_size;
+ uint64_t virtual_disk_size = bs->total_sectors * BDRV_SECTOR_SIZE;
+ uint64_t max_l2_cache = virtual_disk_size / (s->cluster_size / 8);
combined_cache_size_set = qemu_opt_get(opts, QCOW2_OPT_CACHE_SIZE);
l2_cache_size_set = qemu_opt_get(opts, QCOW2_OPT_L2_CACHE_SIZE);
refcount_cache_size_set = qemu_opt_get(opts, QCOW2_OPT_REFCOUNT_CACHE_SIZE);
combined_cache_size = qemu_opt_get_size(opts, QCOW2_OPT_CACHE_SIZE, 0);
- *l2_cache_size = qemu_opt_get_size(opts, QCOW2_OPT_L2_CACHE_SIZE, 0);
+ l2_cache_max_setting = qemu_opt_get_size(opts, QCOW2_OPT_L2_CACHE_SIZE,
+ DEFAULT_L2_CACHE_MAX_SIZE);
*refcount_cache_size = qemu_opt_get_size(opts,
QCOW2_OPT_REFCOUNT_CACHE_SIZE, 0);
*l2_cache_entry_size = qemu_opt_get_size(
opts, QCOW2_OPT_L2_CACHE_ENTRY_SIZE, s->cluster_size);
+ *l2_cache_size = MIN(max_l2_cache, l2_cache_max_setting);
+
if (combined_cache_size_set) {
if (l2_cache_size_set && refcount_cache_size_set) {
error_setg(errp, QCOW2_OPT_CACHE_SIZE ", " QCOW2_OPT_L2_CACHE_SIZE
" and " QCOW2_OPT_REFCOUNT_CACHE_SIZE " may not be set "
"at the same time");
return;
- } else if (*l2_cache_size > combined_cache_size) {
+ } else if (l2_cache_size_set &&
+ (l2_cache_max_setting > combined_cache_size)) {
error_setg(errp, QCOW2_OPT_L2_CACHE_SIZE " may not exceed "
QCOW2_OPT_CACHE_SIZE);
return;
} else if (refcount_cache_size_set) {
*l2_cache_size = combined_cache_size - *refcount_cache_size;
} else {
- uint64_t virtual_disk_size = bs->total_sectors * BDRV_SECTOR_SIZE;
- uint64_t max_l2_cache = virtual_disk_size / (s->cluster_size / 8);
-
/* Assign as much memory as possible to the L2 cache, and
* use the remainder for the refcount cache */
if (combined_cache_size >= max_l2_cache + min_refcount_cache) {
*l2_cache_size = combined_cache_size - *refcount_cache_size;
}
}
- } else {
- if (!l2_cache_size_set) {
- *l2_cache_size = MAX(DEFAULT_L2_CACHE_BYTE_SIZE,
- (uint64_t)DEFAULT_L2_CACHE_CLUSTERS
- * s->cluster_size);
- }
- if (!refcount_cache_size_set) {
- *refcount_cache_size = min_refcount_cache;
- }
}
+ /* l2_cache_size and refcount_cache_size are ensured to have at least
+ * their minimum values in qcow2_update_options_prepare() */
if (*l2_cache_entry_size < (1 << MIN_CLUSTER_BITS) ||
*l2_cache_entry_size > s->cluster_size ||
/* New interval for cache cleanup timer */
r->cache_clean_interval =
qemu_opt_get_number(opts, QCOW2_OPT_CACHE_CLEAN_INTERVAL,
- s->cache_clean_interval);
+ DEFAULT_CACHE_CLEAN_INTERVAL);
#ifndef CONFIG_LINUX
if (r->cache_clean_interval != 0) {
error_setg(errp, QCOW2_OPT_CACHE_CLEAN_INTERVAL
uint64_t ext_end;
uint64_t l1_vm_state_index;
bool update_header = false;
- bool header_updated = false;
ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
if (ret < 0) {
error_setg_errno(errp, -ret, "Could not read qcow2 header");
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);
- be64_to_cpus(&header.size);
- be32_to_cpus(&header.cluster_bits);
- be32_to_cpus(&header.crypt_method);
- be64_to_cpus(&header.l1_table_offset);
- be32_to_cpus(&header.l1_size);
- be64_to_cpus(&header.refcount_table_offset);
- be32_to_cpus(&header.refcount_table_clusters);
- be64_to_cpus(&header.snapshots_offset);
- be32_to_cpus(&header.nb_snapshots);
+ header.magic = be32_to_cpu(header.magic);
+ header.version = be32_to_cpu(header.version);
+ header.backing_file_offset = be64_to_cpu(header.backing_file_offset);
+ header.backing_file_size = be32_to_cpu(header.backing_file_size);
+ header.size = be64_to_cpu(header.size);
+ header.cluster_bits = be32_to_cpu(header.cluster_bits);
+ header.crypt_method = be32_to_cpu(header.crypt_method);
+ header.l1_table_offset = be64_to_cpu(header.l1_table_offset);
+ header.l1_size = be32_to_cpu(header.l1_size);
+ header.refcount_table_offset = be64_to_cpu(header.refcount_table_offset);
+ header.refcount_table_clusters =
+ be32_to_cpu(header.refcount_table_clusters);
+ header.snapshots_offset = be64_to_cpu(header.snapshots_offset);
+ header.nb_snapshots = be32_to_cpu(header.nb_snapshots);
if (header.magic != QCOW_MAGIC) {
error_setg(errp, "Image is not in qcow2 format");
header.refcount_order = 4;
header.header_length = 72;
} else {
- be64_to_cpus(&header.incompatible_features);
- be64_to_cpus(&header.compatible_features);
- be64_to_cpus(&header.autoclear_features);
- be32_to_cpus(&header.refcount_order);
- be32_to_cpus(&header.header_length);
+ header.incompatible_features =
+ be64_to_cpu(header.incompatible_features);
+ header.compatible_features = be64_to_cpu(header.compatible_features);
+ header.autoclear_features = be64_to_cpu(header.autoclear_features);
+ header.refcount_order = be32_to_cpu(header.refcount_order);
+ header.header_length = be32_to_cpu(header.header_length);
if (header.header_length < 104) {
error_setg(errp, "qcow2 header too short");
/* 2^(s->refcount_order - 3) is the refcount width in bytes */
s->refcount_block_bits = s->cluster_bits - (s->refcount_order - 3);
s->refcount_block_size = 1 << s->refcount_block_bits;
- bs->total_sectors = header.size / 512;
+ bs->total_sectors = header.size / BDRV_SECTOR_SIZE;
s->csize_shift = (62 - (s->cluster_bits - 8));
s->csize_mask = (1 << (s->cluster_bits - 8)) - 1;
s->cluster_offset_mask = (1LL << s->csize_shift) - 1;
goto fail;
}
for(i = 0;i < s->l1_size; i++) {
- be64_to_cpus(&s->l1_table[i]);
+ s->l1_table[i] = be64_to_cpu(s->l1_table[i]);
}
}
goto fail;
}
- s->cluster_cache_offset = -1;
s->flags = flags;
ret = qcow2_refcount_init(bs);
cflags |= QCRYPTO_BLOCK_OPEN_NO_IO;
}
s->crypto = qcrypto_block_open(s->crypto_opts, "encrypt.",
- NULL, NULL, cflags, errp);
+ NULL, NULL, cflags, 1, errp);
if (!s->crypto) {
ret = -EINVAL;
goto fail;
s->autoclear_features &= QCOW2_AUTOCLEAR_MASK;
}
- if (s->dirty_bitmaps_loaded) {
- /* It's some kind of reopen. There are no known cases where we need to
- * reload bitmaps in such a situation, so it's safer to skip them.
- *
- * Moreover, if we have some readonly bitmaps and we are reopening for
- * rw we should reopen bitmaps correspondingly.
- */
- if (bdrv_has_readonly_bitmaps(bs) &&
- !bdrv_is_read_only(bs) && !(bdrv_get_flags(bs) & BDRV_O_INACTIVE))
- {
- qcow2_reopen_bitmaps_rw_hint(bs, &header_updated, &local_err);
- }
- } else {
- header_updated = qcow2_load_dirty_bitmaps(bs, &local_err);
- s->dirty_bitmaps_loaded = true;
+ /* == Handle persistent dirty bitmaps ==
+ *
+ * We want load dirty bitmaps in three cases:
+ *
+ * 1. Normal open of the disk in active mode, not related to invalidation
+ * after migration.
+ *
+ * 2. Invalidation of the target vm after pre-copy phase of migration, if
+ * bitmaps are _not_ migrating through migration channel, i.e.
+ * 'dirty-bitmaps' capability is disabled.
+ *
+ * 3. Invalidation of source vm after failed or canceled migration.
+ * This is a very interesting case. There are two possible types of
+ * bitmaps:
+ *
+ * A. Stored on inactivation and removed. They should be loaded from the
+ * image.
+ *
+ * B. Not stored: not-persistent bitmaps and bitmaps, migrated through
+ * the migration channel (with dirty-bitmaps capability).
+ *
+ * On the other hand, there are two possible sub-cases:
+ *
+ * 3.1 disk was changed by somebody else while were inactive. In this
+ * case all in-RAM dirty bitmaps (both persistent and not) are
+ * definitely invalid. And we don't have any method to determine
+ * this.
+ *
+ * Simple and safe thing is to just drop all the bitmaps of type B on
+ * inactivation. But in this case we lose bitmaps in valid 4.2 case.
+ *
+ * On the other hand, resuming source vm, if disk was already changed
+ * is a bad thing anyway: not only bitmaps, the whole vm state is
+ * out of sync with disk.
+ *
+ * This means, that user or management tool, who for some reason
+ * decided to resume source vm, after disk was already changed by
+ * target vm, should at least drop all dirty bitmaps by hand.
+ *
+ * So, we can ignore this case for now, but TODO: "generation"
+ * extension for qcow2, to determine, that image was changed after
+ * last inactivation. And if it is changed, we will drop (or at least
+ * mark as 'invalid' all the bitmaps of type B, both persistent
+ * and not).
+ *
+ * 3.2 disk was _not_ changed while were inactive. Bitmaps may be saved
+ * to disk ('dirty-bitmaps' capability disabled), or not saved
+ * ('dirty-bitmaps' capability enabled), but we don't need to care
+ * of: let's load bitmaps as always: stored bitmaps will be loaded,
+ * and not stored has flag IN_USE=1 in the image and will be skipped
+ * on loading.
+ *
+ * One remaining possible case when we don't want load bitmaps:
+ *
+ * 4. Open disk in inactive mode in target vm (bitmaps are migrating or
+ * will be loaded on invalidation, no needs try loading them before)
+ */
+
+ if (!(bdrv_get_flags(bs) & BDRV_O_INACTIVE)) {
+ /* It's case 1, 2 or 3.2. Or 3.1 which is BUG in management layer. */
+ bool header_updated = qcow2_load_dirty_bitmaps(bs, &local_err);
+
+ update_header = update_header && !header_updated;
}
- update_header = update_header && !header_updated;
if (local_err != NULL) {
error_propagate(errp, local_err);
ret = -EINVAL;
/* From bdrv_co_create. */
qcow2_open_entry(&qoc);
} else {
+ assert(qemu_get_current_aio_context() == qemu_get_aio_context());
qemu_coroutine_enter(qemu_coroutine_create(qcow2_open_entry, &qoc));
BDRV_POLL_WHILE(bs, qoc.ret == -EINPROGRESS);
}
if (bs->encrypted) {
/* Encryption works on a sector granularity */
- bs->bl.request_alignment = BDRV_SECTOR_SIZE;
+ bs->bl.request_alignment = qcrypto_block_get_sector_size(s->crypto);
}
bs->bl.pwrite_zeroes_alignment = s->cluster_size;
bs->bl.pdiscard_alignment = s->cluster_size;
break;
case QCOW2_CLUSTER_COMPRESSED:
- /* add AIO support for compressed blocks ? */
- ret = qcow2_decompress_cluster(bs, cluster_offset);
+ qemu_co_mutex_unlock(&s->lock);
+ ret = qcow2_co_preadv_compressed(bs, cluster_offset,
+ offset, cur_bytes,
+ &hd_qiov);
+ qemu_co_mutex_lock(&s->lock);
if (ret < 0) {
goto fail;
}
- qemu_iovec_from_buf(&hd_qiov, 0,
- s->cluster_cache + offset_in_cluster,
- cur_bytes);
break;
case QCOW2_CLUSTER_NORMAL:
qemu_iovec_init(&hd_qiov, qiov->niov);
- s->cluster_cache_offset = -1; /* disable compressed cache */
-
qemu_co_mutex_lock(&s->lock);
while (bytes != 0) {
qcow2_store_persistent_dirty_bitmaps(bs, &local_err);
if (local_err != NULL) {
result = -EINVAL;
- error_report_err(local_err);
- error_report("Persistent bitmaps are lost for node '%s'",
- bdrv_get_device_or_node_name(bs));
+ error_reportf_err(local_err, "Lost persistent bitmaps during "
+ "inactivation of node '%s': ",
+ bdrv_get_device_or_node_name(bs));
}
ret = qcow2_cache_flush(bs, s->l2_table_cache);
g_free(s->image_backing_file);
g_free(s->image_backing_format);
- g_free(s->cluster_cache);
- qemu_vfree(s->cluster_data);
qcow2_refcount_close(bs);
qcow2_free_snapshots(bs);
}
qemu_co_mutex_unlock(&s->lock);
qobject_unref(options);
if (local_err) {
- error_propagate(errp, local_err);
- error_prepend(errp, "Could not reopen qcow2 layer: ");
+ error_propagate_prepend(errp, local_err,
+ "Could not reopen qcow2 layer: ");
bs->drv = NULL;
return;
} else if (ret < 0) {
/* Full disk encryption header pointer extension */
if (s->crypto_header.offset != 0) {
- cpu_to_be64s(&s->crypto_header.offset);
- cpu_to_be64s(&s->crypto_header.length);
+ s->crypto_header.offset = cpu_to_be64(s->crypto_header.offset);
+ s->crypto_header.length = cpu_to_be64(s->crypto_header.length);
ret = header_ext_add(buf, QCOW2_EXT_MAGIC_CRYPTO_HEADER,
&s->crypto_header, sizeof(s->crypto_header),
buflen);
- be64_to_cpus(&s->crypto_header.offset);
- be64_to_cpus(&s->crypto_header.length);
+ s->crypto_header.offset = be64_to_cpu(s->crypto_header.offset);
+ s->crypto_header.length = be64_to_cpu(s->crypto_header.length);
if (ret < 0) {
goto fail;
}
QCowL2Meta *l2meta = NULL;
assert(!bs->encrypted);
- s->cluster_cache_offset = -1; /* disable compressed cache */
qemu_co_mutex_lock(&s->lock);
uint64_t old_length;
int64_t new_l1_size;
int ret;
+ QDict *options;
if (prealloc != PREALLOC_MODE_OFF && prealloc != PREALLOC_MODE_METADATA &&
prealloc != PREALLOC_MODE_FALLOC && prealloc != PREALLOC_MODE_FULL)
goto fail;
}
- old_length = bs->total_sectors * 512;
+ old_length = bs->total_sectors * BDRV_SECTOR_SIZE;
new_l1_size = size_to_l1(s, offset);
if (offset < old_length) {
}
}
+ bs->total_sectors = offset / BDRV_SECTOR_SIZE;
+
/* write updated header.size */
offset = cpu_to_be64(offset);
ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, size),
}
s->l1_vm_state_index = new_l1_size;
+
+ /* Update cache sizes */
+ options = qdict_clone_shallow(bs->options);
+ ret = qcow2_update_options(bs, options, s->flags, errp);
+ qobject_unref(options);
+ if (ret < 0) {
+ goto fail;
+ }
ret = 0;
fail:
qemu_co_mutex_unlock(&s->lock);
/*
* qcow2_compress()
*
- * @dest - destination buffer, at least of @size-1 bytes
- * @src - source buffer, @size bytes
+ * @dest - destination buffer, @dest_size bytes
+ * @src - source buffer, @src_size bytes
*
* Returns: compressed size on success
- * -1 if compression is inefficient
+ * -1 destination buffer is not enough to store compressed data
* -2 on any other error
*/
-static ssize_t qcow2_compress(void *dest, const void *src, size_t size)
+static ssize_t qcow2_compress(void *dest, size_t dest_size,
+ const void *src, size_t src_size)
{
ssize_t ret;
z_stream strm;
memset(&strm, 0, sizeof(strm));
ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, Z_DEFLATED,
-12, 9, Z_DEFAULT_STRATEGY);
- if (ret != 0) {
+ if (ret != Z_OK) {
return -2;
}
/* strm.next_in is not const in old zlib versions, such as those used on
* OpenBSD/NetBSD, so cast the const away */
- strm.avail_in = size;
+ strm.avail_in = src_size;
strm.next_in = (void *) src;
- strm.avail_out = size - 1;
+ strm.avail_out = dest_size;
strm.next_out = dest;
ret = deflate(&strm, Z_FINISH);
if (ret == Z_STREAM_END) {
- ret = size - 1 - strm.avail_out;
+ ret = dest_size - strm.avail_out;
} else {
ret = (ret == Z_OK ? -1 : -2);
}
return ret;
}
+/*
+ * qcow2_decompress()
+ *
+ * Decompress some data (not more than @src_size bytes) to produce exactly
+ * @dest_size bytes.
+ *
+ * @dest - destination buffer, @dest_size bytes
+ * @src - source buffer, @src_size bytes
+ *
+ * Returns: 0 on success
+ * -1 on fail
+ */
+static ssize_t qcow2_decompress(void *dest, size_t dest_size,
+ const void *src, size_t src_size)
+{
+ int ret = 0;
+ z_stream strm;
+
+ memset(&strm, 0, sizeof(strm));
+ strm.avail_in = src_size;
+ strm.next_in = (void *) src;
+ strm.avail_out = dest_size;
+ strm.next_out = dest;
+
+ ret = inflateInit2(&strm, -12);
+ if (ret != Z_OK) {
+ return -1;
+ }
+
+ ret = inflate(&strm, Z_FINISH);
+ if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) || strm.avail_out != 0) {
+ /* We approve Z_BUF_ERROR because we need @dest buffer to be filled, but
+ * @src buffer may be processed partly (because in qcow2 we know size of
+ * compressed data with precision of one sector) */
+ ret = -1;
+ }
+
+ inflateEnd(&strm);
+
+ return ret;
+}
+
#define MAX_COMPRESS_THREADS 4
+typedef ssize_t (*Qcow2CompressFunc)(void *dest, size_t dest_size,
+ const void *src, size_t src_size);
typedef struct Qcow2CompressData {
void *dest;
+ size_t dest_size;
const void *src;
- size_t size;
+ size_t src_size;
ssize_t ret;
+
+ Qcow2CompressFunc func;
} Qcow2CompressData;
static int qcow2_compress_pool_func(void *opaque)
{
Qcow2CompressData *data = opaque;
- data->ret = qcow2_compress(data->dest, data->src, data->size);
+ data->ret = data->func(data->dest, data->dest_size,
+ data->src, data->src_size);
return 0;
}
qemu_coroutine_enter(opaque);
}
-/* See qcow2_compress definition for parameters description */
-static ssize_t qcow2_co_compress(BlockDriverState *bs,
- void *dest, const void *src, size_t size)
+static ssize_t coroutine_fn
+qcow2_co_do_compress(BlockDriverState *bs, void *dest, size_t dest_size,
+ const void *src, size_t src_size, Qcow2CompressFunc func)
{
BDRVQcow2State *s = bs->opaque;
BlockAIOCB *acb;
ThreadPool *pool = aio_get_thread_pool(bdrv_get_aio_context(bs));
Qcow2CompressData arg = {
.dest = dest,
+ .dest_size = dest_size,
.src = src,
- .size = size,
+ .src_size = src_size,
+ .func = func,
};
while (s->nb_compress_threads >= MAX_COMPRESS_THREADS) {
return arg.ret;
}
+static ssize_t coroutine_fn
+qcow2_co_compress(BlockDriverState *bs, void *dest, size_t dest_size,
+ const void *src, size_t src_size)
+{
+ return qcow2_co_do_compress(bs, dest, dest_size, src, src_size,
+ qcow2_compress);
+}
+
+static ssize_t coroutine_fn
+qcow2_co_decompress(BlockDriverState *bs, void *dest, size_t dest_size,
+ const void *src, size_t src_size)
+{
+ return qcow2_co_do_compress(bs, dest, dest_size, src, src_size,
+ qcow2_decompress);
+}
+
/* XXX: put compressed sectors first, then all the cluster aligned
tables to avoid losing bytes in alignment */
static coroutine_fn int
out_buf = g_malloc(s->cluster_size);
- out_len = qcow2_co_compress(bs, out_buf, buf, s->cluster_size);
+ out_len = qcow2_co_compress(bs, out_buf, s->cluster_size - 1,
+ buf, s->cluster_size);
if (out_len == -2) {
ret = -EINVAL;
goto fail;
return ret;
}
+static int coroutine_fn
+qcow2_co_preadv_compressed(BlockDriverState *bs,
+ uint64_t file_cluster_offset,
+ uint64_t offset,
+ uint64_t bytes,
+ QEMUIOVector *qiov)
+{
+ BDRVQcow2State *s = bs->opaque;
+ int ret = 0, csize, nb_csectors;
+ uint64_t coffset;
+ uint8_t *buf, *out_buf;
+ struct iovec iov;
+ QEMUIOVector local_qiov;
+ int offset_in_cluster = offset_into_cluster(s, offset);
+
+ coffset = file_cluster_offset & s->cluster_offset_mask;
+ nb_csectors = ((file_cluster_offset >> s->csize_shift) & s->csize_mask) + 1;
+ csize = nb_csectors * 512 - (coffset & 511);
+
+ buf = g_try_malloc(csize);
+ if (!buf) {
+ return -ENOMEM;
+ }
+ iov.iov_base = buf;
+ iov.iov_len = csize;
+ qemu_iovec_init_external(&local_qiov, &iov, 1);
+
+ out_buf = qemu_blockalign(bs, s->cluster_size);
+
+ BLKDBG_EVENT(bs->file, BLKDBG_READ_COMPRESSED);
+ ret = bdrv_co_preadv(bs->file, coffset, csize, &local_qiov, 0);
+ if (ret < 0) {
+ goto fail;
+ }
+
+ if (qcow2_co_decompress(bs, out_buf, s->cluster_size, buf, csize) < 0) {
+ ret = -EIO;
+ goto fail;
+ }
+
+ qemu_iovec_from_buf(qiov, 0, out_buf + offset_in_cluster, bytes);
+
+fail:
+ qemu_vfree(out_buf);
+ g_free(buf);
+
+ return ret;
+}
+
static int make_completely_empty(BlockDriverState *bs)
{
BDRVQcow2State *s = bs->opaque;
projects / mirror_qemu.git / blobdiff