diff options
| -rw-r--r-- | block/raw-posix.c | 4 | ||||
| -rw-r--r-- | block_int.h | 3 | ||||
| -rw-r--r-- | qemu-img.c | 4 |
3 files changed, 9 insertions, 2 deletions
diff --git a/block/raw-posix.c b/block/raw-posix.c index 266d8415dc..706799fa39 100644 --- a/block/raw-posix.c +++ b/block/raw-posix.c @@ -1014,6 +1014,7 @@ static BlockDriver bdrv_host_device = { .bdrv_close = raw_close, .bdrv_create = hdev_create, .create_options = raw_create_options, + .no_zero_init = 1, .bdrv_flush = raw_flush, .bdrv_aio_readv = raw_aio_readv, @@ -1110,6 +1111,7 @@ static BlockDriver bdrv_host_floppy = { .bdrv_close = raw_close, .bdrv_create = hdev_create, .create_options = raw_create_options, + .no_zero_init = 1, .bdrv_flush = raw_flush, .bdrv_aio_readv = raw_aio_readv, @@ -1192,6 +1194,7 @@ static BlockDriver bdrv_host_cdrom = { .bdrv_close = raw_close, .bdrv_create = hdev_create, .create_options = raw_create_options, + .no_zero_init = 1, .bdrv_flush = raw_flush, .bdrv_aio_readv = raw_aio_readv, @@ -1313,6 +1316,7 @@ static BlockDriver bdrv_host_cdrom = { .bdrv_close = raw_close, .bdrv_create = hdev_create, .create_options = raw_create_options, + .no_zero_init = 1, .bdrv_flush = raw_flush, .bdrv_aio_readv = raw_aio_readv, diff --git a/block_int.h b/block_int.h index 907e864101..9a3b2e09de 100644 --- a/block_int.h +++ b/block_int.h @@ -117,6 +117,9 @@ struct BlockDriver { /* Returns number of errors in image, -errno for internal errors */ int (*bdrv_check)(BlockDriverState* bs); + /* Set if newly created images are not guaranteed to contain only zeros */ + int no_zero_init; + struct BlockDriver *next; }; diff --git a/qemu-img.c b/qemu-img.c index 972843ab82..f19c6440e1 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -743,7 +743,7 @@ static int img_convert(int argc, char **argv) if (n > bs_offset + bs_sectors - sector_num) n = bs_offset + bs_sectors - sector_num; - if (strcmp(drv->format_name, "host_device")) { + if (!drv->no_zero_init) { /* If the output image is being created as a copy on write image, assume that sectors which are unallocated in the input image are present in both the output's and input's base images (no @@ -776,7 +776,7 @@ static int img_convert(int argc, char **argv) If the output is to a host device, we also write out sectors that are entirely 0, since whatever data was already there is garbage, not 0s. */ - if (strcmp(drv->format_name, "host_device") == 0 || out_baseimg || + if (drv->no_zero_init || out_baseimg || is_allocated_sectors(buf1, n, &n1)) { if (bdrv_write(out_bs, sector_num, buf1, n1) < 0) error("error while writing"); |