#include "qemu/osdep.h"
-#define ZLIB_CONST
-#include <zlib.h>
-
-#include "block/block_int.h"
#include "block/qdict.h"
#include "sysemu/block-backend.h"
#include "qemu/module.h"
#include "qapi/qobject-input-visitor.h"
#include "qapi/qapi-visit-block-core.h"
#include "crypto.h"
-#include "block/thread-pool.h"
/*
Differences with QCOW:
#define QCOW2_EXT_MAGIC_FEATURE_TABLE 0x6803f857
#define QCOW2_EXT_MAGIC_CRYPTO_HEADER 0x0537be77
#define QCOW2_EXT_MAGIC_BITMAPS 0x23852875
+#define QCOW2_EXT_MAGIC_DATA_FILE 0x44415441
static int coroutine_fn
qcow2_co_preadv_compressed(BlockDriverState *bs,
/* Zero fill remaining space in cluster so it has predictable
* content in case of future spec changes */
clusterlen = size_to_clusters(s, headerlen) * s->cluster_size;
- assert(qcow2_pre_write_overlap_check(bs, 0, ret, clusterlen) == 0);
+ assert(qcow2_pre_write_overlap_check(bs, 0, ret, clusterlen, false) == 0);
ret = bdrv_pwrite_zeroes(bs->file,
ret + headerlen,
clusterlen - headerlen, 0);
}
s->crypto = qcrypto_block_open(s->crypto_opts, "encrypt.",
qcow2_crypto_hdr_read_func,
- bs, cflags, 1, errp);
+ bs, cflags, QCOW2_MAX_THREADS, errp);
if (!s->crypto) {
return -EINVAL;
}
#endif
break;
+ case QCOW2_EXT_MAGIC_DATA_FILE:
+ {
+ s->image_data_file = g_malloc0(ext.len + 1);
+ ret = bdrv_pread(bs->file, offset, s->image_data_file, ext.len);
+ if (ret < 0) {
+ error_setg_errno(errp, -ret,
+ "ERROR: Could not read data file name");
+ return ret;
+ }
+#ifdef DEBUG_EXT
+ printf("Qcow2: Got external data file %s\n", s->image_data_file);
+#endif
+ break;
+ }
+
default:
/* unknown magic - save it in case we need to rewrite the header */
/* If you add a new feature, make sure to also update the fast
return 0;
}
+static const char *const mutable_opts[] = {
+ QCOW2_OPT_LAZY_REFCOUNTS,
+ QCOW2_OPT_DISCARD_REQUEST,
+ QCOW2_OPT_DISCARD_SNAPSHOT,
+ QCOW2_OPT_DISCARD_OTHER,
+ QCOW2_OPT_OVERLAP,
+ QCOW2_OPT_OVERLAP_TEMPLATE,
+ QCOW2_OPT_OVERLAP_MAIN_HEADER,
+ QCOW2_OPT_OVERLAP_ACTIVE_L1,
+ QCOW2_OPT_OVERLAP_ACTIVE_L2,
+ QCOW2_OPT_OVERLAP_REFCOUNT_TABLE,
+ QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK,
+ QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE,
+ QCOW2_OPT_OVERLAP_INACTIVE_L1,
+ QCOW2_OPT_OVERLAP_INACTIVE_L2,
+ QCOW2_OPT_OVERLAP_BITMAP_DIRECTORY,
+ QCOW2_OPT_CACHE_SIZE,
+ QCOW2_OPT_L2_CACHE_SIZE,
+ QCOW2_OPT_L2_CACHE_ENTRY_SIZE,
+ QCOW2_OPT_REFCOUNT_CACHE_SIZE,
+ QCOW2_OPT_CACHE_CLEAN_INTERVAL,
+ NULL
+};
+
static QemuOptsList qcow2_runtime_opts = {
.name = "qcow2",
.head = QTAILQ_HEAD_INITIALIZER(qcow2_runtime_opts.head),
BDRVQcow2State *s = bs->opaque;
uint64_t combined_cache_size, l2_cache_max_setting;
bool l2_cache_size_set, refcount_cache_size_set, combined_cache_size_set;
+ bool l2_cache_entry_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);
+ l2_cache_entry_size_set = qemu_opt_get(opts, QCOW2_OPT_L2_CACHE_ENTRY_SIZE);
combined_cache_size = qemu_opt_get_size(opts, QCOW2_OPT_CACHE_SIZE, 0);
l2_cache_max_setting = qemu_opt_get_size(opts, QCOW2_OPT_L2_CACHE_SIZE,
}
}
}
+
+ /*
+ * If the L2 cache is not enough to cover the whole disk then
+ * default to 4KB entries. Smaller entries reduce the cost of
+ * loads and evictions and increase I/O performance.
+ */
+ if (*l2_cache_size < max_l2_cache && !l2_cache_entry_size_set) {
+ *l2_cache_entry_size = MIN(s->cluster_size, 4096);
+ }
+
/* l2_cache_size and refcount_cache_size are ensured to have at least
* their minimum values in qcow2_update_options_prepare() */
s->cluster_bits = header.cluster_bits;
s->cluster_size = 1 << s->cluster_bits;
- s->cluster_sectors = 1 << (s->cluster_bits - BDRV_SECTOR_BITS);
/* Initialise version 3 header fields */
if (header.version == 2) {
goto fail;
}
+ /* Open external data file */
+ s->data_file = bdrv_open_child(NULL, options, "data-file", bs, &child_file,
+ true, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ if (s->incompatible_features & QCOW2_INCOMPAT_DATA_FILE) {
+ if (!s->data_file && s->image_data_file) {
+ s->data_file = bdrv_open_child(s->image_data_file, options,
+ "data-file", bs, &child_file,
+ false, errp);
+ if (!s->data_file) {
+ ret = -EINVAL;
+ goto fail;
+ }
+ }
+ if (!s->data_file) {
+ error_setg(errp, "'data-file' is required for this image");
+ ret = -EINVAL;
+ goto fail;
+ }
+ } else {
+ if (s->data_file) {
+ error_setg(errp, "'data-file' can only be set for images with an "
+ "external data file");
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ s->data_file = bs->file;
+
+ if (data_file_is_raw(bs)) {
+ error_setg(errp, "data-file-raw requires a data file");
+ ret = -EINVAL;
+ goto fail;
+ }
+ }
+
/* qcow2_read_extension may have set up the crypto context
* if the crypt method needs a header region, some methods
* don't need header extensions, so must check here
cflags |= QCRYPTO_BLOCK_OPEN_NO_IO;
}
s->crypto = qcrypto_block_open(s->crypto_opts, "encrypt.",
- NULL, NULL, cflags, 1, errp);
+ NULL, NULL, cflags,
+ QCOW2_MAX_THREADS, errp);
if (!s->crypto) {
ret = -EINVAL;
goto fail;
}
#endif
- qemu_co_queue_init(&s->compress_wait_queue);
+ qemu_co_queue_init(&s->thread_task_queue);
return ret;
fail:
+ g_free(s->image_data_file);
+ if (has_data_file(bs)) {
+ bdrv_unref_child(bs, s->data_file);
+ }
g_free(s->unknown_header_fields);
cleanup_unknown_header_ext(bs);
qcow2_free_snapshots(bs);
unsigned int bytes;
int status = 0;
+ if (!s->metadata_preallocation_checked) {
+ ret = qcow2_detect_metadata_preallocation(bs);
+ s->metadata_preallocation = (ret == 1);
+ s->metadata_preallocation_checked = true;
+ }
+
bytes = MIN(INT_MAX, count);
qemu_co_mutex_lock(&s->lock);
ret = qcow2_get_cluster_offset(bs, offset, &bytes, &cluster_offset);
*pnum = bytes;
- if (cluster_offset != 0 && ret != QCOW2_CLUSTER_COMPRESSED &&
+ if ((ret == QCOW2_CLUSTER_NORMAL || ret == QCOW2_CLUSTER_ZERO_ALLOC) &&
!s->crypto) {
index_in_cluster = offset & (s->cluster_size - 1);
*map = cluster_offset | index_in_cluster;
- *file = bs->file->bs;
+ *file = s->data_file->bs;
status |= BDRV_BLOCK_OFFSET_VALID;
}
if (ret == QCOW2_CLUSTER_ZERO_PLAIN || ret == QCOW2_CLUSTER_ZERO_ALLOC) {
} else if (ret != QCOW2_CLUSTER_UNALLOCATED) {
status |= BDRV_BLOCK_DATA;
}
+ if (s->metadata_preallocation && (status & BDRV_BLOCK_DATA) &&
+ (status & BDRV_BLOCK_OFFSET_VALID))
+ {
+ status |= BDRV_BLOCK_RECURSE;
+ }
return status;
}
qemu_iovec_init(&hd_qiov, qiov->niov);
- qemu_co_mutex_lock(&s->lock);
-
while (bytes != 0) {
/* prepare next request */
QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size);
}
+ qemu_co_mutex_lock(&s->lock);
ret = qcow2_get_cluster_offset(bs, offset, &cur_bytes, &cluster_offset);
+ qemu_co_mutex_unlock(&s->lock);
if (ret < 0) {
goto fail;
}
if (bs->backing) {
BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO);
- qemu_co_mutex_unlock(&s->lock);
ret = bdrv_co_preadv(bs->backing, offset, cur_bytes,
&hd_qiov, 0);
- qemu_co_mutex_lock(&s->lock);
if (ret < 0) {
goto fail;
}
break;
case QCOW2_CLUSTER_COMPRESSED:
- 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;
}
*/
if (!cluster_data) {
cluster_data =
- qemu_try_blockalign(bs->file->bs,
+ qemu_try_blockalign(s->data_file->bs,
QCOW_MAX_CRYPT_CLUSTERS
* s->cluster_size);
if (cluster_data == NULL) {
}
BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO);
- qemu_co_mutex_unlock(&s->lock);
- ret = bdrv_co_preadv(bs->file,
+ ret = bdrv_co_preadv(s->data_file,
cluster_offset + offset_in_cluster,
cur_bytes, &hd_qiov, 0);
- qemu_co_mutex_lock(&s->lock);
if (ret < 0) {
goto fail;
}
assert(s->crypto);
assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0);
assert((cur_bytes & (BDRV_SECTOR_SIZE - 1)) == 0);
- if (qcrypto_block_decrypt(s->crypto,
- (s->crypt_physical_offset ?
- cluster_offset + offset_in_cluster :
- offset),
- cluster_data,
- cur_bytes,
- NULL) < 0) {
+ if (qcow2_co_decrypt(bs, cluster_offset, offset,
+ cluster_data, cur_bytes) < 0) {
ret = -EIO;
goto fail;
}
ret = 0;
fail:
- qemu_co_mutex_unlock(&s->lock);
-
qemu_iovec_destroy(&hd_qiov);
qemu_vfree(cluster_data);
continue;
}
+ /* If COW regions are handled already, skip this too */
+ if (m->skip_cow) {
+ continue;
+ }
+
/* The data (middle) region must be immediately after the
* start region */
if (l2meta_cow_start(m) + m->cow_start.nb_bytes != offset) {
return false;
}
+static bool is_unallocated(BlockDriverState *bs, int64_t offset, int64_t bytes)
+{
+ int64_t nr;
+ return !bytes ||
+ (!bdrv_is_allocated_above(bs, NULL, false, offset, bytes, &nr) &&
+ nr == bytes);
+}
+
+static bool is_zero_cow(BlockDriverState *bs, QCowL2Meta *m)
+{
+ /*
+ * This check is designed for optimization shortcut so it must be
+ * efficient.
+ * Instead of is_zero(), use is_unallocated() as it is faster (but not
+ * as accurate and can result in false negatives).
+ */
+ return is_unallocated(bs, m->offset + m->cow_start.offset,
+ m->cow_start.nb_bytes) &&
+ is_unallocated(bs, m->offset + m->cow_end.offset,
+ m->cow_end.nb_bytes);
+}
+
+static int handle_alloc_space(BlockDriverState *bs, QCowL2Meta *l2meta)
+{
+ BDRVQcow2State *s = bs->opaque;
+ QCowL2Meta *m;
+
+ if (!(s->data_file->bs->supported_zero_flags & BDRV_REQ_NO_FALLBACK)) {
+ return 0;
+ }
+
+ if (bs->encrypted) {
+ return 0;
+ }
+
+ for (m = l2meta; m != NULL; m = m->next) {
+ int ret;
+
+ if (!m->cow_start.nb_bytes && !m->cow_end.nb_bytes) {
+ continue;
+ }
+
+ if (!is_zero_cow(bs, m)) {
+ continue;
+ }
+
+ /*
+ * instead of writing zero COW buffers,
+ * efficiently zero out the whole clusters
+ */
+
+ ret = qcow2_pre_write_overlap_check(bs, 0, m->alloc_offset,
+ m->nb_clusters * s->cluster_size,
+ true);
+ if (ret < 0) {
+ return ret;
+ }
+
+ BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC_SPACE);
+ ret = bdrv_co_pwrite_zeroes(s->data_file, m->alloc_offset,
+ m->nb_clusters * s->cluster_size,
+ BDRV_REQ_NO_FALLBACK);
+ if (ret < 0) {
+ if (ret != -ENOTSUP && ret != -EAGAIN) {
+ return ret;
+ }
+ continue;
+ }
+
+ trace_qcow2_skip_cow(qemu_coroutine_self(), m->offset, m->nb_clusters);
+ m->skip_cow = true;
+ }
+ return 0;
+}
+
static coroutine_fn int qcow2_co_pwritev(BlockDriverState *bs, uint64_t offset,
uint64_t bytes, QEMUIOVector *qiov,
int flags)
ret = qcow2_alloc_cluster_offset(bs, offset, &cur_bytes,
&cluster_offset, &l2meta);
if (ret < 0) {
- goto fail;
+ goto out_locked;
}
assert((cluster_offset & 511) == 0);
+ ret = qcow2_pre_write_overlap_check(bs, 0,
+ cluster_offset + offset_in_cluster,
+ cur_bytes, true);
+ if (ret < 0) {
+ goto out_locked;
+ }
+
+ qemu_co_mutex_unlock(&s->lock);
+
qemu_iovec_reset(&hd_qiov);
qemu_iovec_concat(&hd_qiov, qiov, bytes_done, cur_bytes);
* s->cluster_size);
if (cluster_data == NULL) {
ret = -ENOMEM;
- goto fail;
+ goto out_unlocked;
}
}
QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size);
qemu_iovec_to_buf(&hd_qiov, 0, cluster_data, hd_qiov.size);
- if (qcrypto_block_encrypt(s->crypto,
- (s->crypt_physical_offset ?
- cluster_offset + offset_in_cluster :
- offset),
- cluster_data,
- cur_bytes, NULL) < 0) {
+ if (qcow2_co_encrypt(bs, cluster_offset, offset,
+ cluster_data, cur_bytes) < 0) {
ret = -EIO;
- goto fail;
+ goto out_unlocked;
}
qemu_iovec_reset(&hd_qiov);
qemu_iovec_add(&hd_qiov, cluster_data, cur_bytes);
}
- ret = qcow2_pre_write_overlap_check(bs, 0,
- cluster_offset + offset_in_cluster, cur_bytes);
+ /* Try to efficiently initialize the physical space with zeroes */
+ ret = handle_alloc_space(bs, l2meta);
if (ret < 0) {
- goto fail;
+ goto out_unlocked;
}
/* If we need to do COW, check if it's possible to merge the
* If it's not possible (or not necessary) then write the
* guest data now. */
if (!merge_cow(offset, cur_bytes, &hd_qiov, l2meta)) {
- qemu_co_mutex_unlock(&s->lock);
BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO);
trace_qcow2_writev_data(qemu_coroutine_self(),
cluster_offset + offset_in_cluster);
- ret = bdrv_co_pwritev(bs->file,
+ ret = bdrv_co_pwritev(s->data_file,
cluster_offset + offset_in_cluster,
cur_bytes, &hd_qiov, 0);
- qemu_co_mutex_lock(&s->lock);
if (ret < 0) {
- goto fail;
+ goto out_unlocked;
}
}
+ qemu_co_mutex_lock(&s->lock);
+
ret = qcow2_handle_l2meta(bs, &l2meta, true);
if (ret) {
- goto fail;
+ goto out_locked;
}
bytes -= cur_bytes;
trace_qcow2_writev_done_part(qemu_coroutine_self(), cur_bytes);
}
ret = 0;
+ goto out_locked;
-fail:
+out_unlocked:
+ qemu_co_mutex_lock(&s->lock);
+
+out_locked:
qcow2_handle_l2meta(bs, &l2meta, false);
qemu_co_mutex_unlock(&s->lock);
g_free(s->unknown_header_fields);
cleanup_unknown_header_ext(bs);
+ g_free(s->image_data_file);
g_free(s->image_backing_file);
g_free(s->image_backing_format);
+ if (has_data_file(bs)) {
+ bdrv_unref_child(bs, s->data_file);
+ }
+
qcow2_refcount_close(bs);
qcow2_free_snapshots(bs);
}
buflen -= ret;
}
+ /* External data file header extension */
+ if (has_data_file(bs) && s->image_data_file) {
+ ret = header_ext_add(buf, QCOW2_EXT_MAGIC_DATA_FILE,
+ s->image_data_file, strlen(s->image_data_file),
+ buflen);
+ if (ret < 0) {
+ goto fail;
+ }
+
+ buf += ret;
+ buflen -= ret;
+ }
+
/* Full disk encryption header pointer extension */
if (s->crypto_header.offset != 0) {
s->crypto_header.offset = cpu_to_be64(s->crypto_header.offset);
.bit = QCOW2_INCOMPAT_CORRUPT_BITNR,
.name = "corrupt bit",
},
+ {
+ .type = QCOW2_FEAT_TYPE_INCOMPATIBLE,
+ .bit = QCOW2_INCOMPAT_DATA_FILE_BITNR,
+ .name = "external data file",
+ },
{
.type = QCOW2_FEAT_TYPE_COMPATIBLE,
.bit = QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
{
BDRVQcow2State *s = bs->opaque;
+ /* Adding a backing file means that the external data file alone won't be
+ * enough to make sense of the content */
+ if (backing_file && data_file_is_raw(bs)) {
+ return -EINVAL;
+ }
+
if (backing_file && strlen(backing_file) > 1023) {
return -EINVAL;
}
* Returns: 0 on success, -errno on failure.
*/
static int coroutine_fn preallocate_co(BlockDriverState *bs, uint64_t offset,
- uint64_t new_length)
+ uint64_t new_length, PreallocMode mode,
+ Error **errp)
{
+ BDRVQcow2State *s = bs->opaque;
uint64_t bytes;
uint64_t host_offset = 0;
+ int64_t file_length;
unsigned int cur_bytes;
int ret;
QCowL2Meta *meta;
bytes = new_length - offset;
while (bytes) {
- cur_bytes = MIN(bytes, INT_MAX);
+ cur_bytes = MIN(bytes, QEMU_ALIGN_DOWN(INT_MAX, s->cluster_size));
ret = qcow2_alloc_cluster_offset(bs, offset, &cur_bytes,
&host_offset, &meta);
if (ret < 0) {
+ error_setg_errno(errp, -ret, "Allocating clusters failed");
return ret;
}
ret = qcow2_alloc_cluster_link_l2(bs, meta);
if (ret < 0) {
+ error_setg_errno(errp, -ret, "Mapping clusters failed");
qcow2_free_any_clusters(bs, meta->alloc_offset,
meta->nb_clusters, QCOW2_DISCARD_NEVER);
return ret;
* all of the allocated clusters (otherwise we get failing reads after
* EOF). Extend the image to the last allocated sector.
*/
- if (host_offset != 0) {
- uint8_t data = 0;
- ret = bdrv_pwrite(bs->file, (host_offset + cur_bytes) - 1,
- &data, 1);
+ file_length = bdrv_getlength(s->data_file->bs);
+ if (file_length < 0) {
+ error_setg_errno(errp, -file_length, "Could not get file size");
+ return file_length;
+ }
+
+ if (host_offset + cur_bytes > file_length) {
+ if (mode == PREALLOC_MODE_METADATA) {
+ mode = PREALLOC_MODE_OFF;
+ }
+ ret = bdrv_co_truncate(s->data_file, host_offset + cur_bytes, mode,
+ errp);
if (ret < 0) {
return ret;
}
*/
BlockBackend *blk = NULL;
BlockDriverState *bs = NULL;
+ BlockDriverState *data_bs = NULL;
QCowHeader *header;
size_t cluster_size;
int version;
}
refcount_order = ctz32(qcow2_opts->refcount_bits);
+ if (qcow2_opts->data_file_raw && !qcow2_opts->data_file) {
+ error_setg(errp, "data-file-raw requires data-file");
+ ret = -EINVAL;
+ goto out;
+ }
+ if (qcow2_opts->data_file_raw && qcow2_opts->has_backing_file) {
+ error_setg(errp, "Backing file and data-file-raw cannot be used at "
+ "the same time");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (qcow2_opts->data_file) {
+ if (version < 3) {
+ error_setg(errp, "External data files are only supported with "
+ "compatibility level 1.1 and above (use version=v3 or "
+ "greater)");
+ ret = -EINVAL;
+ goto out;
+ }
+ data_bs = bdrv_open_blockdev_ref(qcow2_opts->data_file, errp);
+ if (data_bs == NULL) {
+ ret = -EIO;
+ goto out;
+ }
+ }
/* Create BlockBackend to write to the image */
- blk = blk_new(BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL);
+ blk = blk_new(bdrv_get_aio_context(bs),
+ BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL);
ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
goto out;
goto out;
}
- if (qcow2_opts->preallocation == PREALLOC_MODE_FULL ||
- qcow2_opts->preallocation == PREALLOC_MODE_FALLOC)
- {
- int64_t prealloc_size =
- qcow2_calc_prealloc_size(qcow2_opts->size, cluster_size,
- refcount_order);
-
- ret = blk_truncate(blk, prealloc_size, qcow2_opts->preallocation, errp);
- if (ret < 0) {
- goto out;
- }
- }
-
/* Write the header */
QEMU_BUILD_BUG_ON((1 << MIN_CLUSTER_BITS) < sizeof(*header));
header = g_malloc0(cluster_size);
header->compatible_features |=
cpu_to_be64(QCOW2_COMPAT_LAZY_REFCOUNTS);
}
+ if (data_bs) {
+ header->incompatible_features |=
+ cpu_to_be64(QCOW2_INCOMPAT_DATA_FILE);
+ }
+ if (qcow2_opts->data_file_raw) {
+ header->autoclear_features |=
+ cpu_to_be64(QCOW2_AUTOCLEAR_DATA_FILE_RAW);
+ }
ret = blk_pwrite(blk, 0, header, cluster_size, 0);
g_free(header);
options = qdict_new();
qdict_put_str(options, "driver", "qcow2");
qdict_put_str(options, "file", bs->node_name);
+ if (data_bs) {
+ qdict_put_str(options, "data-file", data_bs->node_name);
+ }
blk = blk_new_open(NULL, NULL, options,
BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_NO_FLUSH,
&local_err);
abort();
}
+ /* Set the external data file if necessary */
+ if (data_bs) {
+ BDRVQcow2State *s = blk_bs(blk)->opaque;
+ s->image_data_file = g_strdup(data_bs->filename);
+ }
+
/* Create a full header (including things like feature table) */
ret = qcow2_update_header(blk_bs(blk));
if (ret < 0) {
}
/* Okay, now that we have a valid image, let's give it the right size */
- ret = blk_truncate(blk, qcow2_opts->size, PREALLOC_MODE_OFF, errp);
+ ret = blk_truncate(blk, qcow2_opts->size, qcow2_opts->preallocation, errp);
if (ret < 0) {
error_prepend(errp, "Could not resize image: ");
goto out;
}
}
- /* And if we're supposed to preallocate metadata, do that now */
- if (qcow2_opts->preallocation != PREALLOC_MODE_OFF) {
- BDRVQcow2State *s = blk_bs(blk)->opaque;
- qemu_co_mutex_lock(&s->lock);
- ret = preallocate_co(blk_bs(blk), 0, qcow2_opts->size);
- qemu_co_mutex_unlock(&s->lock);
-
- if (ret < 0) {
- error_setg_errno(errp, -ret, "Could not preallocate metadata");
- goto out;
- }
- }
-
blk_unref(blk);
blk = NULL;
options = qdict_new();
qdict_put_str(options, "driver", "qcow2");
qdict_put_str(options, "file", bs->node_name);
+ if (data_bs) {
+ qdict_put_str(options, "data-file", data_bs->node_name);
+ }
blk = blk_new_open(NULL, NULL, options,
BDRV_O_RDWR | BDRV_O_NO_BACKING | BDRV_O_NO_IO,
&local_err);
out:
blk_unref(blk);
bdrv_unref(bs);
+ bdrv_unref(data_bs);
return ret;
}
QDict *qdict;
Visitor *v;
BlockDriverState *bs = NULL;
+ BlockDriverState *data_bs = NULL;
Error *local_err = NULL;
const char *val;
int ret;
{ BLOCK_OPT_REFCOUNT_BITS, "refcount-bits" },
{ BLOCK_OPT_ENCRYPT, BLOCK_OPT_ENCRYPT_FORMAT },
{ BLOCK_OPT_COMPAT_LEVEL, "version" },
+ { BLOCK_OPT_DATA_FILE_RAW, "data-file-raw" },
{ NULL, NULL },
};
goto finish;
}
+ /* Create and open an external data file (protocol layer) */
+ val = qdict_get_try_str(qdict, BLOCK_OPT_DATA_FILE);
+ if (val) {
+ ret = bdrv_create_file(val, opts, errp);
+ if (ret < 0) {
+ goto finish;
+ }
+
+ data_bs = bdrv_open(val, NULL, NULL,
+ BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL,
+ errp);
+ if (data_bs == NULL) {
+ ret = -EIO;
+ goto finish;
+ }
+
+ qdict_del(qdict, BLOCK_OPT_DATA_FILE);
+ qdict_put_str(qdict, "data-file", data_bs->node_name);
+ }
+
/* Set 'driver' and 'node' options */
qdict_put_str(qdict, "driver", "qcow2");
qdict_put_str(qdict, "file", bs->node_name);
finish:
qobject_unref(qdict);
bdrv_unref(bs);
+ bdrv_unref(data_bs);
qapi_free_BlockdevCreateOptions(create_options);
return ret;
}
goto out;
case QCOW2_CLUSTER_NORMAL:
- child = bs->file;
+ child = s->data_file;
copy_offset += offset_into_cluster(s, src_offset);
if ((copy_offset & 511) != 0) {
ret = -EIO;
assert((cluster_offset & 511) == 0);
ret = qcow2_pre_write_overlap_check(bs, 0,
- cluster_offset + offset_in_cluster, cur_bytes);
+ cluster_offset + offset_in_cluster, cur_bytes, true);
if (ret < 0) {
goto fail;
}
qemu_co_mutex_unlock(&s->lock);
ret = bdrv_co_copy_range_to(src, src_offset,
- bs->file,
+ s->data_file,
cluster_offset + offset_in_cluster,
cur_bytes, read_flags, write_flags);
qemu_co_mutex_lock(&s->lock);
}
/* cannot proceed if image has bitmaps */
- if (s->nb_bitmaps) {
- /* TODO: resize bitmaps in the image */
- error_setg(errp, "Can't resize an image which has bitmaps");
+ if (qcow2_truncate_bitmaps_check(bs, errp)) {
ret = -ENOTSUP;
goto fail;
}
switch (prealloc) {
case PREALLOC_MODE_OFF:
+ if (has_data_file(bs)) {
+ ret = bdrv_co_truncate(s->data_file, offset, prealloc, errp);
+ if (ret < 0) {
+ goto fail;
+ }
+ }
break;
case PREALLOC_MODE_METADATA:
- ret = preallocate_co(bs, old_length, offset);
+ ret = preallocate_co(bs, old_length, offset, prealloc, errp);
if (ret < 0) {
- error_setg_errno(errp, -ret, "Preallocation failed");
goto fail;
}
break;
int64_t old_file_size, new_file_size;
uint64_t nb_new_data_clusters, nb_new_l2_tables;
+ /* With a data file, preallocation means just allocating the metadata
+ * and forwarding the truncate request to the data file */
+ if (has_data_file(bs)) {
+ ret = preallocate_co(bs, old_length, offset, prealloc, errp);
+ if (ret < 0) {
+ goto fail;
+ }
+ break;
+ }
+
old_file_size = bdrv_getlength(bs->file->bs);
if (old_file_size < 0) {
error_setg_errno(errp, -old_file_size,
return ret;
}
-/*
- * qcow2_compress()
- *
- * @dest - destination buffer, @dest_size bytes
- * @src - source buffer, @src_size bytes
- *
- * Returns: compressed size on success
- * -1 destination buffer is not enough to store compressed data
- * -2 on any other error
- */
-static ssize_t qcow2_compress(void *dest, size_t dest_size,
- const void *src, size_t src_size)
-{
- ssize_t ret;
- z_stream strm;
-
- /* 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 != 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 = src_size;
- strm.next_in = (void *) src;
- strm.avail_out = dest_size;
- strm.next_out = dest;
-
- ret = deflate(&strm, Z_FINISH);
- if (ret == Z_STREAM_END) {
- ret = dest_size - strm.avail_out;
- } else {
- ret = (ret == Z_OK ? -1 : -2);
- }
-
- deflateEnd(&strm);
-
- 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 src_size;
- ssize_t ret;
-
- Qcow2CompressFunc func;
-} Qcow2CompressData;
-
-static int qcow2_compress_pool_func(void *opaque)
-{
- Qcow2CompressData *data = opaque;
-
- data->ret = data->func(data->dest, data->dest_size,
- data->src, data->src_size);
-
- return 0;
-}
-
-static void qcow2_compress_complete(void *opaque, int ret)
-{
- qemu_coroutine_enter(opaque);
-}
-
-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,
- .src_size = src_size,
- .func = func,
- };
-
- while (s->nb_compress_threads >= MAX_COMPRESS_THREADS) {
- qemu_co_queue_wait(&s->compress_wait_queue, NULL);
- }
-
- s->nb_compress_threads++;
- acb = thread_pool_submit_aio(pool, qcow2_compress_pool_func, &arg,
- qcow2_compress_complete,
- qemu_coroutine_self());
-
- if (!acb) {
- s->nb_compress_threads--;
- return -EINVAL;
- }
- qemu_coroutine_yield();
- s->nb_compress_threads--;
- qemu_co_queue_next(&s->compress_wait_queue);
-
- 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
uint64_t bytes, QEMUIOVector *qiov)
{
BDRVQcow2State *s = bs->opaque;
- QEMUIOVector hd_qiov;
int ret;
- size_t out_len;
+ ssize_t out_len;
uint8_t *buf, *out_buf;
- int64_t cluster_offset;
+ uint64_t cluster_offset;
+
+ if (has_data_file(bs)) {
+ return -ENOTSUP;
+ }
if (bytes == 0) {
/* align end of file to a sector boundary to ease reading with
sector based I/Os */
- cluster_offset = bdrv_getlength(bs->file->bs);
- if (cluster_offset < 0) {
- return cluster_offset;
+ int64_t len = bdrv_getlength(bs->file->bs);
+ if (len < 0) {
+ return len;
}
- return bdrv_co_truncate(bs->file, cluster_offset, PREALLOC_MODE_OFF,
- NULL);
+ return bdrv_co_truncate(bs->file, len, PREALLOC_MODE_OFF, NULL);
}
if (offset_into_cluster(s, offset)) {
out_len = qcow2_co_compress(bs, out_buf, s->cluster_size - 1,
buf, s->cluster_size);
- if (out_len == -2) {
- ret = -EINVAL;
- goto fail;
- } else if (out_len == -1) {
+ if (out_len == -ENOMEM) {
/* could not compress: write normal cluster */
ret = qcow2_co_pwritev(bs, offset, bytes, qiov, 0);
if (ret < 0) {
goto fail;
}
goto success;
+ } else if (out_len < 0) {
+ ret = -EINVAL;
+ goto fail;
}
qemu_co_mutex_lock(&s->lock);
- cluster_offset =
- qcow2_alloc_compressed_cluster_offset(bs, offset, out_len);
- if (!cluster_offset) {
+ ret = qcow2_alloc_compressed_cluster_offset(bs, offset, out_len,
+ &cluster_offset);
+ if (ret < 0) {
qemu_co_mutex_unlock(&s->lock);
- ret = -EIO;
goto fail;
}
- cluster_offset &= s->cluster_offset_mask;
- ret = qcow2_pre_write_overlap_check(bs, 0, cluster_offset, out_len);
+ ret = qcow2_pre_write_overlap_check(bs, 0, cluster_offset, out_len, true);
qemu_co_mutex_unlock(&s->lock);
if (ret < 0) {
goto fail;
}
- qemu_iovec_init_buf(&hd_qiov, out_buf, out_len);
-
- BLKDBG_EVENT(bs->file, BLKDBG_WRITE_COMPRESSED);
- ret = bdrv_co_pwritev(bs->file, cluster_offset, out_len, &hd_qiov, 0);
+ BLKDBG_EVENT(s->data_file, BLKDBG_WRITE_COMPRESSED);
+ ret = bdrv_co_pwrite(s->data_file, cluster_offset, out_len, out_buf, 0);
if (ret < 0) {
goto fail;
}
int ret = 0, csize, nb_csectors;
uint64_t coffset;
uint8_t *buf, *out_buf;
- 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);
+ csize = nb_csectors * QCOW2_COMPRESSED_SECTOR_SIZE -
+ (coffset & ~QCOW2_COMPRESSED_SECTOR_MASK);
buf = g_try_malloc(csize);
if (!buf) {
return -ENOMEM;
}
- qemu_iovec_init_buf(&local_qiov, buf, csize);
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);
+ ret = bdrv_co_pread(bs->file, coffset, csize, buf, 0);
if (ret < 0) {
goto fail;
}
if (s->qcow_version >= 3 && !s->snapshots && !s->nb_bitmaps &&
3 + l1_clusters <= s->refcount_block_size &&
- s->crypt_method_header != QCOW_CRYPT_LUKS) {
+ s->crypt_method_header != QCOW_CRYPT_LUKS &&
+ !has_data_file(bs)) {
/* The following function only works for qcow2 v3 images (it
* requires the dirty flag) and only as long as there are no
* features that reserve extra clusters (such as snapshots,
* LUKS header, or persistent bitmaps), because it completely
* empties the image. Furthermore, the L1 table and three
* additional clusters (image header, refcount table, one
- * refcount block) have to fit inside one refcount block. */
+ * refcount block) have to fit inside one refcount block. It
+ * only resets the image file, i.e. does not work with an
+ * external data file. */
return make_completely_empty(bs);
}
.refcount_bits = s->refcount_bits,
.has_bitmaps = !!bitmaps,
.bitmaps = bitmaps,
+ .has_data_file = !!s->image_data_file,
+ .data_file = g_strdup(s->image_data_file),
+ .has_data_file_raw = has_data_file(bs),
+ .data_file_raw = data_file_is_raw(bs),
};
} else {
/* if this assertion fails, this probably means a new version was
return -ENOTSUP;
}
+ if (has_data_file(bs)) {
+ error_setg(errp, "Cannot downgrade an image with a data file");
+ return -ENOTSUP;
+ }
+
/* clear incompatible features */
if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) {
ret = qcow2_mark_clean(bs);
BDRVQcow2State *s = bs->opaque;
int old_version = s->qcow_version, new_version = old_version;
uint64_t new_size = 0;
- const char *backing_file = NULL, *backing_format = NULL;
+ const char *backing_file = NULL, *backing_format = NULL, *data_file = NULL;
bool lazy_refcounts = s->use_lazy_refcounts;
+ bool data_file_raw = data_file_is_raw(bs);
const char *compat = NULL;
uint64_t cluster_size = s->cluster_size;
bool encrypt;
"may not exceed 64 bits");
return -EINVAL;
}
+ } else if (!strcmp(desc->name, BLOCK_OPT_DATA_FILE)) {
+ data_file = qemu_opt_get(opts, BLOCK_OPT_DATA_FILE);
+ if (data_file && !has_data_file(bs)) {
+ error_setg(errp, "data-file can only be set for images that "
+ "use an external data file");
+ return -EINVAL;
+ }
+ } else if (!strcmp(desc->name, BLOCK_OPT_DATA_FILE_RAW)) {
+ data_file_raw = qemu_opt_get_bool(opts, BLOCK_OPT_DATA_FILE_RAW,
+ data_file_raw);
+ if (data_file_raw && !data_file_is_raw(bs)) {
+ error_setg(errp, "data-file-raw cannot be set on existing "
+ "images");
+ return -EINVAL;
+ }
} else {
/* if this point is reached, this probably means a new option was
* added without having it covered here */
}
}
+ /* data-file-raw blocks backing files, so clear it first if requested */
+ if (data_file_raw) {
+ s->autoclear_features |= QCOW2_AUTOCLEAR_DATA_FILE_RAW;
+ } else {
+ s->autoclear_features &= ~QCOW2_AUTOCLEAR_DATA_FILE_RAW;
+ }
+
+ if (data_file) {
+ g_free(s->image_data_file);
+ s->image_data_file = *data_file ? g_strdup(data_file) : NULL;
+ }
+
+ ret = qcow2_update_header(bs);
+ if (ret < 0) {
+ error_setg_errno(errp, -ret, "Failed to update the image header");
+ return ret;
+ }
+
if (backing_file || backing_format) {
ret = qcow2_change_backing_file(bs,
backing_file ?: s->image_backing_file,
}
if (new_size) {
- BlockBackend *blk = blk_new(BLK_PERM_RESIZE, BLK_PERM_ALL);
+ BlockBackend *blk = blk_new(bdrv_get_aio_context(bs),
+ BLK_PERM_RESIZE, BLK_PERM_ALL);
ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
blk_unref(blk);
.type = QEMU_OPT_STRING,
.help = "Image format of the base image"
},
+ {
+ .name = BLOCK_OPT_DATA_FILE,
+ .type = QEMU_OPT_STRING,
+ .help = "File name of an external data file"
+ },
+ {
+ .name = BLOCK_OPT_DATA_FILE_RAW,
+ .type = QEMU_OPT_BOOL,
+ .help = "The external data file must stay valid as a raw image"
+ },
{
.name = BLOCK_OPT_ENCRYPT,
.type = QEMU_OPT_BOOL,
.create_opts = &qcow2_create_opts,
.strong_runtime_opts = qcow2_strong_runtime_opts,
+ .mutable_opts = mutable_opts,
.bdrv_co_check = qcow2_co_check,
.bdrv_amend_options = qcow2_amend_options,
projects / mirror_qemu.git / blobdiff