diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/io.c | 56 |
1 files changed, 45 insertions, 11 deletions
diff --git a/block/io.c b/block/io.c index e2959920b8..ccf79c33c5 100644 --- a/block/io.c +++ b/block/io.c @@ -1531,28 +1531,54 @@ static int64_t coroutine_fn bdrv_co_get_block_status(BlockDriverState *bs, return ret; } -/* Coroutine wrapper for bdrv_get_block_status() */ -static void coroutine_fn bdrv_get_block_status_co_entry(void *opaque) +static int64_t coroutine_fn bdrv_co_get_block_status_above(BlockDriverState *bs, + BlockDriverState *base, + int64_t sector_num, + int nb_sectors, + int *pnum) +{ + BlockDriverState *p; + int64_t ret = 0; + + assert(bs != base); + for (p = bs; p != base; p = p->backing_hd) { + ret = bdrv_co_get_block_status(p, sector_num, nb_sectors, pnum); + if (ret < 0 || ret & BDRV_BLOCK_ALLOCATED) { + break; + } + /* [sector_num, pnum] unallocated on this layer, which could be only + * the first part of [sector_num, nb_sectors]. */ + nb_sectors = MIN(nb_sectors, *pnum); + } + return ret; +} + +/* Coroutine wrapper for bdrv_get_block_status_above() */ +static void coroutine_fn bdrv_get_block_status_above_co_entry(void *opaque) { BdrvCoGetBlockStatusData *data = opaque; - BlockDriverState *bs = data->bs; - data->ret = bdrv_co_get_block_status(bs, data->sector_num, data->nb_sectors, - data->pnum); + data->ret = bdrv_co_get_block_status_above(data->bs, data->base, + data->sector_num, + data->nb_sectors, + data->pnum); data->done = true; } /* - * Synchronous wrapper around bdrv_co_get_block_status(). + * Synchronous wrapper around bdrv_co_get_block_status_above(). * - * See bdrv_co_get_block_status() for details. + * See bdrv_co_get_block_status_above() for details. */ -int64_t bdrv_get_block_status(BlockDriverState *bs, int64_t sector_num, - int nb_sectors, int *pnum) +int64_t bdrv_get_block_status_above(BlockDriverState *bs, + BlockDriverState *base, + int64_t sector_num, + int nb_sectors, int *pnum) { Coroutine *co; BdrvCoGetBlockStatusData data = { .bs = bs, + .base = base, .sector_num = sector_num, .nb_sectors = nb_sectors, .pnum = pnum, @@ -1561,11 +1587,11 @@ int64_t bdrv_get_block_status(BlockDriverState *bs, int64_t sector_num, if (qemu_in_coroutine()) { /* Fast-path if already in coroutine context */ - bdrv_get_block_status_co_entry(&data); + bdrv_get_block_status_above_co_entry(&data); } else { AioContext *aio_context = bdrv_get_aio_context(bs); - co = qemu_coroutine_create(bdrv_get_block_status_co_entry); + co = qemu_coroutine_create(bdrv_get_block_status_above_co_entry); qemu_coroutine_enter(co, &data); while (!data.done) { aio_poll(aio_context, true); @@ -1574,6 +1600,14 @@ int64_t bdrv_get_block_status(BlockDriverState *bs, int64_t sector_num, return data.ret; } +int64_t bdrv_get_block_status(BlockDriverState *bs, + int64_t sector_num, + int nb_sectors, int *pnum) +{ + return bdrv_get_block_status_above(bs, bs->backing_hd, + sector_num, nb_sectors, pnum); +} + int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum) { |