diff options
Diffstat (limited to 'block.c')
| -rw-r--r-- | block.c | 102 |
1 files changed, 91 insertions, 11 deletions
diff --git a/block.c b/block.c index 7b8b14d971..28508f21d1 100644 --- a/block.c +++ b/block.c @@ -1768,17 +1768,6 @@ int bdrv_has_zero_init(BlockDriverState *bs) return 1; } -int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors) -{ - if (!bs->drv) { - return -ENOMEDIUM; - } - if (!bs->drv->bdrv_discard) { - return 0; - } - return bs->drv->bdrv_discard(bs, sector_num, nb_sectors); -} - /* * Returns true iff the specified sector is present in the disk image. Drivers * not implementing the functionality are assumed to not support backing files, @@ -2754,6 +2743,34 @@ BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs, return &acb->common; } +static void coroutine_fn bdrv_aio_discard_co_entry(void *opaque) +{ + BlockDriverAIOCBCoroutine *acb = opaque; + BlockDriverState *bs = acb->common.bs; + + acb->req.error = bdrv_co_discard(bs, acb->req.sector, acb->req.nb_sectors); + acb->bh = qemu_bh_new(bdrv_co_em_bh, acb); + qemu_bh_schedule(acb->bh); +} + +BlockDriverAIOCB *bdrv_aio_discard(BlockDriverState *bs, + int64_t sector_num, int nb_sectors, + BlockDriverCompletionFunc *cb, void *opaque) +{ + Coroutine *co; + BlockDriverAIOCBCoroutine *acb; + + trace_bdrv_aio_discard(bs, sector_num, nb_sectors, opaque); + + acb = qemu_aio_get(&bdrv_em_co_aio_pool, bs, cb, opaque); + acb->req.sector = sector_num; + acb->req.nb_sectors = nb_sectors; + co = qemu_coroutine_create(bdrv_aio_discard_co_entry); + qemu_coroutine_enter(co, acb); + + return &acb->common; +} + void bdrv_init(void) { module_call_init(MODULE_INIT_BLOCK); @@ -2915,6 +2932,69 @@ int bdrv_flush(BlockDriverState *bs) return rwco.ret; } +static void coroutine_fn bdrv_discard_co_entry(void *opaque) +{ + RwCo *rwco = opaque; + + rwco->ret = bdrv_co_discard(rwco->bs, rwco->sector_num, rwco->nb_sectors); +} + +int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, + int nb_sectors) +{ + if (!bs->drv) { + return -ENOMEDIUM; + } else if (bdrv_check_request(bs, sector_num, nb_sectors)) { + return -EIO; + } else if (bs->read_only) { + return -EROFS; + } else if (bs->drv->bdrv_co_discard) { + return bs->drv->bdrv_co_discard(bs, sector_num, nb_sectors); + } else if (bs->drv->bdrv_aio_discard) { + BlockDriverAIOCB *acb; + CoroutineIOCompletion co = { + .coroutine = qemu_coroutine_self(), + }; + + acb = bs->drv->bdrv_aio_discard(bs, sector_num, nb_sectors, + bdrv_co_io_em_complete, &co); + if (acb == NULL) { + return -EIO; + } else { + qemu_coroutine_yield(); + return co.ret; + } + } else if (bs->drv->bdrv_discard) { + return bs->drv->bdrv_discard(bs, sector_num, nb_sectors); + } else { + return 0; + } +} + +int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors) +{ + Coroutine *co; + RwCo rwco = { + .bs = bs, + .sector_num = sector_num, + .nb_sectors = nb_sectors, + .ret = NOT_DONE, + }; + + if (qemu_in_coroutine()) { + /* Fast-path if already in coroutine context */ + bdrv_discard_co_entry(&rwco); + } else { + co = qemu_coroutine_create(bdrv_discard_co_entry); + qemu_coroutine_enter(co, &rwco); + while (rwco.ret == NOT_DONE) { + qemu_aio_wait(); + } + } + + return rwco.ret; +} + /**************************************************************/ /* removable device support */ |