Commit 7cdb1f6d authored by MORITA Kazutaka's avatar MORITA Kazutaka Committed by Kevin Wolf
Browse files

block: call the snapshot handlers of the protocol drivers 



When snapshot handlers are not defined in the format driver, it is
better to call the ones of the protocol driver.  This enables us to
implement snapshot support in the protocol driver.

We need to call bdrv_close() and bdrv_open() handlers of the format
driver before and after bdrv_snapshot_goto() call of the protocol.  It is
because the contents of the block driver state may need to be changed
after loading vmstate.

Signed-off-by: default avatarMORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent 2bc93fed

block.c

+43 −18
Original line number Diff line number Diff line
@@ -1631,9 +1631,11 @@ int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 
    BlockDriver *drv = bs->drv;

    if (!drv)

        return -ENOMEDIUM;

    if (!drv->bdrv_save_vmstate)

        return -ENOTSUP;

    if (drv->bdrv_save_vmstate)

        return drv->bdrv_save_vmstate(bs, buf, pos, size);

    if (bs->file)

        return bdrv_save_vmstate(bs->file, buf, pos, size);

    return -ENOTSUP;

}



int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
@@ -1642,9 +1644,11 @@ int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 
    BlockDriver *drv = bs->drv;

    if (!drv)

        return -ENOMEDIUM;

    if (!drv->bdrv_load_vmstate)

        return -ENOTSUP;

    if (drv->bdrv_load_vmstate)

        return drv->bdrv_load_vmstate(bs, buf, pos, size);

    if (bs->file)

        return bdrv_load_vmstate(bs->file, buf, pos, size);

    return -ENOTSUP;

}



void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event)
@@ -1668,20 +1672,37 @@ int bdrv_snapshot_create(BlockDriverState *bs, 
    BlockDriver *drv = bs->drv;

    if (!drv)

        return -ENOMEDIUM;

    if (!drv->bdrv_snapshot_create)

        return -ENOTSUP;

    if (drv->bdrv_snapshot_create)

        return drv->bdrv_snapshot_create(bs, sn_info);

    if (bs->file)

        return bdrv_snapshot_create(bs->file, sn_info);

    return -ENOTSUP;

}



int bdrv_snapshot_goto(BlockDriverState *bs,

                       const char *snapshot_id)

{

    BlockDriver *drv = bs->drv;

    int ret, open_ret;



    if (!drv)

        return -ENOMEDIUM;

    if (!drv->bdrv_snapshot_goto)

        return -ENOTSUP;

    if (drv->bdrv_snapshot_goto)

        return drv->bdrv_snapshot_goto(bs, snapshot_id);



    if (bs->file) {

        drv->bdrv_close(bs);

        ret = bdrv_snapshot_goto(bs->file, snapshot_id);

        open_ret = drv->bdrv_open(bs, bs->open_flags);

        if (open_ret < 0) {

            bdrv_delete(bs->file);

            bs->drv = NULL;

            return open_ret;

        }

        return ret;

    }



    return -ENOTSUP;

}



int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
@@ -1689,9 +1710,11 @@ int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id) 
    BlockDriver *drv = bs->drv;

    if (!drv)

        return -ENOMEDIUM;

    if (!drv->bdrv_snapshot_delete)

        return -ENOTSUP;

    if (drv->bdrv_snapshot_delete)

        return drv->bdrv_snapshot_delete(bs, snapshot_id);

    if (bs->file)

        return bdrv_snapshot_delete(bs->file, snapshot_id);

    return -ENOTSUP;

}



int bdrv_snapshot_list(BlockDriverState *bs,
@@ -1700,9 +1723,11 @@ int bdrv_snapshot_list(BlockDriverState *bs, 
    BlockDriver *drv = bs->drv;

    if (!drv)

        return -ENOMEDIUM;

    if (!drv->bdrv_snapshot_list)

        return -ENOTSUP;

    if (drv->bdrv_snapshot_list)

        return drv->bdrv_snapshot_list(bs, psn_info);

    if (bs->file)

        return bdrv_snapshot_list(bs->file, psn_info);

    return -ENOTSUP;

}



#define NB_SUFFIXES 4