* THE SOFTWARE.
*/
#include "qemu-common.h"
-#include "block_int.h"
-#include "module.h"
+#include "block/block_int.h"
+#include "qemu/module.h"
#include <zlib.h>
-#include "aes.h"
+#include "block/aes.h"
#include "block/qcow2.h"
-#include "qemu-error.h"
-#include "qerror.h"
+#include "qemu/error-report.h"
+#include "qapi/qmp/qerror.h"
#include "trace.h"
/*
uint32_t magic;
uint32_t len;
} QCowExtension;
+
#define QCOW2_EXT_MAGIC_END 0
#define QCOW2_EXT_MAGIC_BACKING_FORMAT 0xE2792ACA
#define QCOW2_EXT_MAGIC_FEATURE_TABLE 0x6803f857
}
}
+/*
+ * Sets the dirty bit and flushes afterwards if necessary.
+ *
+ * The incompatible_features bit is only set if the image file header was
+ * updated successfully. Therefore it is not required to check the return
+ * value of this function.
+ */
+int qcow2_mark_dirty(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+ uint64_t val;
+ int ret;
+
+ assert(s->qcow_version >= 3);
+
+ if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) {
+ return 0; /* already dirty */
+ }
+
+ val = cpu_to_be64(s->incompatible_features | QCOW2_INCOMPAT_DIRTY);
+ ret = bdrv_pwrite(bs->file, offsetof(QCowHeader, incompatible_features),
+ &val, sizeof(val));
+ if (ret < 0) {
+ return ret;
+ }
+ ret = bdrv_flush(bs->file);
+ if (ret < 0) {
+ return ret;
+ }
+
+ /* Only treat image as dirty if the header was updated successfully */
+ s->incompatible_features |= QCOW2_INCOMPAT_DIRTY;
+ return 0;
+}
+
+/*
+ * Clears the dirty bit and flushes before if necessary. Only call this
+ * function when there are no pending requests, it does not guard against
+ * concurrent requests dirtying the image.
+ */
+static int qcow2_mark_clean(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+
+ if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) {
+ int ret = bdrv_flush(bs);
+ if (ret < 0) {
+ return ret;
+ }
+
+ s->incompatible_features &= ~QCOW2_INCOMPAT_DIRTY;
+ return qcow2_update_header(bs);
+ }
+ return 0;
+}
+
+static int qcow2_check(BlockDriverState *bs, BdrvCheckResult *result,
+ BdrvCheckMode fix)
+{
+ int ret = qcow2_check_refcounts(bs, result, fix);
+ if (ret < 0) {
+ return ret;
+ }
+
+ if (fix && result->check_errors == 0 && result->corruptions == 0) {
+ return qcow2_mark_clean(bs);
+ }
+ return ret;
+}
+
static int qcow2_open(BlockDriverState *bs, int flags)
{
BDRVQcowState *s = bs->opaque;
s->compatible_features = header.compatible_features;
s->autoclear_features = header.autoclear_features;
- if (s->incompatible_features != 0) {
+ if (s->incompatible_features & ~QCOW2_INCOMPAT_MASK) {
void *feature_table = NULL;
qcow2_read_extensions(bs, header.header_length, ext_end,
&feature_table);
report_unsupported_feature(bs, feature_table,
- s->incompatible_features);
+ s->incompatible_features &
+ ~QCOW2_INCOMPAT_MASK);
ret = -ENOTSUP;
goto fail;
}
/* Initialise locks */
qemu_co_mutex_init(&s->lock);
+ /* Repair image if dirty */
+ if (!(flags & BDRV_O_CHECK) && !bs->read_only &&
+ (s->incompatible_features & QCOW2_INCOMPAT_DIRTY)) {
+ BdrvCheckResult result = {0};
+
+ ret = qcow2_check(bs, &result, BDRV_FIX_ERRORS);
+ if (ret < 0) {
+ goto fail;
+ }
+ }
+
#ifdef DEBUG_ALLOC
{
BdrvCheckResult result = {0};
return 0;
}
+/* We have nothing to do for QCOW2 reopen, stubs just return
+ * success */
+static int qcow2_reopen_prepare(BDRVReopenState *state,
+ BlockReopenQueue *queue, Error **errp)
+{
+ return 0;
+}
+
static int coroutine_fn qcow2_co_is_allocated(BlockDriverState *bs,
int64_t sector_num, int nb_sectors, int *pnum)
{
else
n1 = bs->total_sectors - sector_num;
- qemu_iovec_memset_skip(qiov, 0, 512 * (nb_sectors - n1), 512 * n1);
+ qemu_iovec_memset(qiov, 512 * n1, 0, 512 * (nb_sectors - n1));
return n1;
}
index_in_cluster = sector_num & (s->cluster_sectors - 1);
qemu_iovec_reset(&hd_qiov);
- qemu_iovec_copy(&hd_qiov, qiov, bytes_done,
+ qemu_iovec_concat(&hd_qiov, qiov, bytes_done,
cur_nr_sectors * 512);
switch (ret) {
}
} else {
/* Note: in this case, no need to wait */
- qemu_iovec_memset(&hd_qiov, 0, 512 * cur_nr_sectors);
+ qemu_iovec_memset(&hd_qiov, 0, 0, 512 * cur_nr_sectors);
}
break;
ret = -EIO;
goto fail;
}
- qemu_iovec_memset(&hd_qiov, 0, 512 * cur_nr_sectors);
+ qemu_iovec_memset(&hd_qiov, 0, 0, 512 * cur_nr_sectors);
break;
case QCOW2_CLUSTER_COMPRESSED:
goto fail;
}
- qemu_iovec_from_buffer(&hd_qiov,
+ qemu_iovec_from_buf(&hd_qiov, 0,
s->cluster_cache + index_in_cluster * 512,
512 * cur_nr_sectors);
break;
if (s->crypt_method) {
qcow2_encrypt_sectors(s, sector_num, cluster_data,
cluster_data, cur_nr_sectors, 0, &s->aes_decrypt_key);
- qemu_iovec_reset(&hd_qiov);
- qemu_iovec_copy(&hd_qiov, qiov, bytes_done,
- cur_nr_sectors * 512);
- qemu_iovec_from_buffer(&hd_qiov, cluster_data,
- 512 * cur_nr_sectors);
+ qemu_iovec_from_buf(qiov, bytes_done,
+ cluster_data, 512 * cur_nr_sectors);
}
break;
return ret;
}
-static void run_dependent_requests(BDRVQcowState *s, QCowL2Meta *m)
-{
- /* Take the request off the list of running requests */
- if (m->nb_clusters != 0) {
- QLIST_REMOVE(m, next_in_flight);
- }
-
- /* Restart all dependent requests */
- if (!qemu_co_queue_empty(&m->dependent_requests)) {
- qemu_co_mutex_unlock(&s->lock);
- qemu_co_queue_restart_all(&m->dependent_requests);
- qemu_co_mutex_lock(&s->lock);
- }
-}
-
static coroutine_fn int qcow2_co_writev(BlockDriverState *bs,
int64_t sector_num,
int remaining_sectors,
QEMUIOVector hd_qiov;
uint64_t bytes_done = 0;
uint8_t *cluster_data = NULL;
- QCowL2Meta l2meta = {
- .nb_clusters = 0,
- };
+ QCowL2Meta *l2meta;
trace_qcow2_writev_start_req(qemu_coroutine_self(), sector_num,
remaining_sectors);
- qemu_co_queue_init(&l2meta.dependent_requests);
-
qemu_iovec_init(&hd_qiov, qiov->niov);
s->cluster_cache_offset = -1; /* disable compressed cache */
while (remaining_sectors != 0) {
+ l2meta = NULL;
+
trace_qcow2_writev_start_part(qemu_coroutine_self());
index_in_cluster = sector_num & (s->cluster_sectors - 1);
n_end = index_in_cluster + remaining_sectors;
}
ret = qcow2_alloc_cluster_offset(bs, sector_num << 9,
- index_in_cluster, n_end, &cur_nr_sectors, &l2meta);
+ index_in_cluster, n_end, &cur_nr_sectors, &cluster_offset, &l2meta);
if (ret < 0) {
goto fail;
}
- cluster_offset = l2meta.cluster_offset;
assert((cluster_offset & 511) == 0);
qemu_iovec_reset(&hd_qiov);
- qemu_iovec_copy(&hd_qiov, qiov, bytes_done,
+ qemu_iovec_concat(&hd_qiov, qiov, bytes_done,
cur_nr_sectors * 512);
if (s->crypt_method) {
assert(hd_qiov.size <=
QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size);
- qemu_iovec_to_buffer(&hd_qiov, cluster_data);
+ qemu_iovec_to_buf(&hd_qiov, 0, cluster_data, hd_qiov.size);
qcow2_encrypt_sectors(s, sector_num, cluster_data,
cluster_data, cur_nr_sectors, 1, &s->aes_encrypt_key);
cur_nr_sectors * 512);
}
- BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO);
qemu_co_mutex_unlock(&s->lock);
+ BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO);
trace_qcow2_writev_data(qemu_coroutine_self(),
(cluster_offset >> 9) + index_in_cluster);
ret = bdrv_co_writev(bs->file,
goto fail;
}
- ret = qcow2_alloc_cluster_link_l2(bs, &l2meta);
- if (ret < 0) {
- goto fail;
- }
+ if (l2meta != NULL) {
+ ret = qcow2_alloc_cluster_link_l2(bs, l2meta);
+ if (ret < 0) {
+ goto fail;
+ }
+
+ /* Take the request off the list of running requests */
+ if (l2meta->nb_clusters != 0) {
+ QLIST_REMOVE(l2meta, next_in_flight);
+ }
- run_dependent_requests(s, &l2meta);
+ qemu_co_mutex_unlock(&s->lock);
+ qemu_co_queue_restart_all(&l2meta->dependent_requests);
+ qemu_co_mutex_lock(&s->lock);
+
+ g_free(l2meta);
+ l2meta = NULL;
+ }
remaining_sectors -= cur_nr_sectors;
sector_num += cur_nr_sectors;
ret = 0;
fail:
- run_dependent_requests(s, &l2meta);
-
qemu_co_mutex_unlock(&s->lock);
+ if (l2meta != NULL) {
+ if (l2meta->nb_clusters != 0) {
+ QLIST_REMOVE(l2meta, next_in_flight);
+ }
+ qemu_co_queue_restart_all(&l2meta->dependent_requests);
+ g_free(l2meta);
+ }
+
qemu_iovec_destroy(&hd_qiov);
qemu_vfree(cluster_data);
trace_qcow2_writev_done_req(qemu_coroutine_self(), ret);
qcow2_cache_flush(bs, s->l2_table_cache);
qcow2_cache_flush(bs, s->refcount_block_cache);
+ qcow2_mark_clean(bs);
+
qcow2_cache_destroy(bs, s->l2_table_cache);
qcow2_cache_destroy(bs, s->refcount_block_cache);
/* Feature table */
Qcow2Feature features[] = {
- /* no feature defined yet */
+ {
+ .type = QCOW2_FEAT_TYPE_INCOMPATIBLE,
+ .bit = QCOW2_INCOMPAT_DIRTY_BITNR,
+ .name = "dirty bit",
+ },
+ {
+ .type = QCOW2_FEAT_TYPE_COMPATIBLE,
+ .bit = QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
+ .name = "lazy refcounts",
+ },
};
ret = header_ext_add(buf, QCOW2_EXT_MAGIC_FEATURE_TABLE,
goto fail;
}
+ /* Using strncpy is ok here, since buf is not NUL-terminated. */
strncpy(buf, bs->backing_file, buflen);
header->backing_file_offset = cpu_to_be64(buf - ((char*) header));
{
uint64_t nb_sectors;
uint64_t offset;
+ uint64_t host_offset = 0;
int num;
int ret;
- QCowL2Meta meta;
+ QCowL2Meta *meta;
nb_sectors = bdrv_getlength(bs) >> 9;
offset = 0;
- qemu_co_queue_init(&meta.dependent_requests);
- meta.cluster_offset = 0;
while (nb_sectors) {
num = MIN(nb_sectors, INT_MAX >> 9);
- ret = qcow2_alloc_cluster_offset(bs, offset, 0, num, &num, &meta);
+ ret = qcow2_alloc_cluster_offset(bs, offset, 0, num, &num,
+ &host_offset, &meta);
if (ret < 0) {
return ret;
}
- ret = qcow2_alloc_cluster_link_l2(bs, &meta);
+ ret = qcow2_alloc_cluster_link_l2(bs, meta);
if (ret < 0) {
- qcow2_free_any_clusters(bs, meta.cluster_offset, meta.nb_clusters);
+ qcow2_free_any_clusters(bs, meta->alloc_offset, meta->nb_clusters);
return ret;
}
/* There are no dependent requests, but we need to remove our request
* from the list of in-flight requests */
- run_dependent_requests(bs->opaque, &meta);
+ if (meta != NULL) {
+ QLIST_REMOVE(meta, next_in_flight);
+ }
/* TODO Preallocate data if requested */
* all of the allocated clusters (otherwise we get failing reads after
* EOF). Extend the image to the last allocated sector.
*/
- if (meta.cluster_offset != 0) {
+ if (host_offset != 0) {
uint8_t buf[512];
memset(buf, 0, 512);
- ret = bdrv_write(bs->file, (meta.cluster_offset >> 9) + num - 1, buf, 1);
+ ret = bdrv_write(bs->file, (host_offset >> 9) + num - 1, buf, 1);
if (ret < 0) {
return ret;
}
header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE);
}
+ if (flags & BLOCK_FLAG_LAZY_REFCOUNTS) {
+ header.compatible_features |=
+ cpu_to_be64(QCOW2_COMPAT_LAZY_REFCOUNTS);
+ }
+
ret = bdrv_pwrite(bs, 0, &header, sizeof(header));
if (ret < 0) {
goto out;
options->value.s);
return -EINVAL;
}
+ } else if (!strcmp(options->name, BLOCK_OPT_LAZY_REFCOUNTS)) {
+ flags |= options->value.n ? BLOCK_FLAG_LAZY_REFCOUNTS : 0;
}
options++;
}
return -EINVAL;
}
+ if (version < 3 && (flags & BLOCK_FLAG_LAZY_REFCOUNTS)) {
+ fprintf(stderr, "Lazy refcounts only supported with compatibility "
+ "level 1.1 and above (use compat=1.1 or greater)\n");
+ return -EINVAL;
+ }
+
return qcow2_create2(filename, sectors, backing_file, backing_fmt, flags,
cluster_size, prealloc, options, version);
}
return ret;
}
- ret = qcow2_cache_flush(bs, s->refcount_block_cache);
- if (ret < 0) {
- qemu_co_mutex_unlock(&s->lock);
- return ret;
+ if (qcow2_need_accurate_refcounts(s)) {
+ ret = qcow2_cache_flush(bs, s->refcount_block_cache);
+ if (ret < 0) {
+ qemu_co_mutex_unlock(&s->lock);
+ return ret;
+ }
}
qemu_co_mutex_unlock(&s->lock);
return 0;
}
-
-static int qcow2_check(BlockDriverState *bs, BdrvCheckResult *result,
- BdrvCheckMode fix)
-{
- return qcow2_check_refcounts(bs, result, fix);
-}
-
#if 0
static void dump_refcounts(BlockDriverState *bs)
{
.type = OPT_STRING,
.help = "Preallocation mode (allowed values: off, metadata)"
},
+ {
+ .name = BLOCK_OPT_LAZY_REFCOUNTS,
+ .type = OPT_FLAG,
+ .help = "Postpone refcount updates",
+ },
{ NULL }
};
.bdrv_probe = qcow2_probe,
.bdrv_open = qcow2_open,
.bdrv_close = qcow2_close,
+ .bdrv_reopen_prepare = qcow2_reopen_prepare,
.bdrv_create = qcow2_create,
.bdrv_co_is_allocated = qcow2_co_is_allocated,
.bdrv_set_key = qcow2_set_key,
projects / qemu.git / blobdiff