Commit 77a5a000 authored by Stefan Hajnoczi's avatar Stefan Hajnoczi Committed by Kevin Wolf
Browse files

qed: support for growing images 



The .bdrv_truncate() operation resizes images and growing is easy to
implement in QED.  Simply check that the new size is valid and then
update the image_size header field to reflect the new size.

Signed-off-by: default avatarStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent f6a00aa1

block/qed.c

+21 −1
Original line number Diff line number Diff line
@@ -1333,9 +1333,29 @@ static BlockDriverAIOCB *bdrv_qed_aio_flush(BlockDriverState *bs, 


static int bdrv_qed_truncate(BlockDriverState *bs, int64_t offset)

{

    BDRVQEDState *s = bs->opaque;

    uint64_t old_image_size;

    int ret;



    if (!qed_is_image_size_valid(offset, s->header.cluster_size,

                                 s->header.table_size)) {

        return -EINVAL;

    }



    /* Shrinking is currently not supported */

    if ((uint64_t)offset < s->header.image_size) {

        return -ENOTSUP;

    }



    old_image_size = s->header.image_size;

    s->header.image_size = offset;

    ret = qed_write_header_sync(s);

    if (ret < 0) {

        s->header.image_size = old_image_size;

    }

    return ret;

}



static int64_t bdrv_qed_getlength(BlockDriverState *bs)

{

    BDRVQEDState *s = bs->opaque;