This adds a preallocation=full mode to qcow2 image creation, which
creates a non-sparse image file.
Signed-off-by: Hu Tao <hu...@cn.fujitsu.com>
---
block/qcow2.c | 20 ++++++++++++++++----
1 file changed, 16 insertions(+), 4 deletions(-)
diff --git a/block/qcow2.c b/block/qcow2.c
index 487a595..3c41d4a 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -1386,7 +1386,7 @@ static int qcow2_change_backing_file(BlockDriverState *bs,
return qcow2_update_header(bs);
}
-static int preallocate(BlockDriverState *bs)
+static int preallocate(BlockDriverState *bs, enum prealloc_mode mode)
{
uint64_t nb_sectors;
uint64_t offset;
@@ -1395,9 +1395,19 @@ static int preallocate(BlockDriverState *bs)
int ret;
QCowL2Meta *meta;
+ assert(mode != PREALLOC_OFF);
+
nb_sectors = bdrv_getlength(bs) >> 9;
offset = 0;
+ if (mode == PREALLOC_FULL) {
+ ret = bdrv_preallocate(bs->file, 0, bdrv_getlength(bs));
+ if (ret < 0) {
+ return ret;
+ }
+ }
+
+ /* allocate metadata */
while (nb_sectors) {
num = MIN(nb_sectors, INT_MAX >> 9);
ret = qcow2_alloc_cluster_offset(bs, offset, 0, num, &num,
@@ -1577,11 +1587,11 @@ static int qcow2_create2(const char *filename, int64_t
total_size,
}
}
- /* And if we're supposed to preallocate metadata, do that now */
+ /* And if we're supposed to preallocate data, do that now */
if (prealloc) {
BDRVQcowState *s = bs->opaque;
qemu_co_mutex_lock(&s->lock);
- ret = preallocate(bs);
+ ret = preallocate(bs, prealloc);
qemu_co_mutex_unlock(&s->lock);
if (ret < 0) {
error_setg_errno(errp, -ret, "Could not preallocate metadata");
@@ -1638,6 +1648,8 @@ static int qcow2_create(const char *filename,
QEMUOptionParameter *options,
prealloc = PREALLOC_OFF;
} else if (!strcmp(options->value.s, "metadata")) {
prealloc = PREALLOC_METADATA;
+ } else if (!strcmp(options->value.s, "full")) {
+ prealloc = PREALLOC_FULL;
} else {
error_setg(errp, "Invalid preallocation mode: '%s'",
options->value.s);
@@ -2229,7 +2241,7 @@ static QEMUOptionParameter qcow2_create_options[] = {
{
.name = BLOCK_OPT_PREALLOC,
.type = OPT_STRING,
- .help = "Preallocation mode (allowed values: off, metadata)"
+ .help = "Preallocation mode (allowed values: off, metadata, full)"
},
{
.name = BLOCK_OPT_LAZY_REFCOUNTS,
--
1.7.11.7
