From 922453bca6a927bb527068ae8679d587cfa45dbc Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Wed, 30 Nov 2011 12:23:43 +0000 Subject: block: convert qemu_aio_flush() calls to bdrv_drain_all() Many places in QEMU call qemu_aio_flush() to complete all pending asynchronous I/O. Most of these places actually want to drain all block requests but there is no block layer API to do so. This patch introduces the bdrv_drain_all() API to wait for requests across all BlockDriverStates to complete. As a bonus we perform checks after qemu_aio_wait() to ensure that requests really have finished. Signed-off-by: Stefan Hajnoczi Signed-off-by: Kevin Wolf --- block-migration.c | 2 +- block.c | 19 +++++++++++++++++++ block.h | 1 + blockdev.c | 4 ++-- cpus.c | 2 +- hw/ide/macio.c | 5 +++-- hw/ide/pci.c | 2 +- hw/virtio-blk.c | 2 +- hw/xen_platform.c | 2 +- qemu-io.c | 4 ++-- savevm.c | 2 +- xen-mapcache.c | 2 +- 12 files changed, 34 insertions(+), 13 deletions(-) diff --git a/block-migration.c b/block-migration.c index 5f10486416..423c5a07b6 100644 --- a/block-migration.c +++ b/block-migration.c @@ -387,7 +387,7 @@ static int mig_save_device_dirty(Monitor *mon, QEMUFile *f, for (sector = bmds->cur_dirty; sector < bmds->total_sectors;) { if (bmds_aio_inflight(bmds, sector)) { - qemu_aio_flush(); + bdrv_drain_all(); } if (bdrv_get_dirty(bmds->bs, sector)) { diff --git a/block.c b/block.c index 50ce2be48e..aa9d14245b 100644 --- a/block.c +++ b/block.c @@ -846,6 +846,25 @@ void bdrv_close_all(void) } } +/* + * Wait for pending requests to complete across all BlockDriverStates + * + * This function does not flush data to disk, use bdrv_flush_all() for that + * after calling this function. + */ +void bdrv_drain_all(void) +{ + BlockDriverState *bs; + + qemu_aio_flush(); + + /* If requests are still pending there is a bug somewhere */ + QTAILQ_FOREACH(bs, &bdrv_states, list) { + assert(QLIST_EMPTY(&bs->tracked_requests)); + assert(qemu_co_queue_empty(&bs->throttled_reqs)); + } +} + /* make a BlockDriverState anonymous by removing from bdrv_state list. Also, NULL terminate the device_name to prevent double remove */ void bdrv_make_anon(BlockDriverState *bs) diff --git a/block.h b/block.h index 5f8a98a746..1790f9988c 100644 --- a/block.h +++ b/block.h @@ -214,6 +214,7 @@ int bdrv_flush(BlockDriverState *bs); int coroutine_fn bdrv_co_flush(BlockDriverState *bs); void bdrv_flush_all(void); void bdrv_close_all(void); +void bdrv_drain_all(void); int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors); int bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors); diff --git a/blockdev.c b/blockdev.c index af4e239b93..dbf0251a77 100644 --- a/blockdev.c +++ b/blockdev.c @@ -653,7 +653,7 @@ int do_snapshot_blkdev(Monitor *mon, const QDict *qdict, QObject **ret_data) goto out; } - qemu_aio_flush(); + bdrv_drain_all(); bdrv_flush(bs); bdrv_close(bs); @@ -840,7 +840,7 @@ int do_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data) } /* quiesce block driver; prevent further io */ - qemu_aio_flush(); + bdrv_drain_all(); bdrv_flush(bs); bdrv_close(bs); diff --git a/cpus.c b/cpus.c index 82530c4a03..58e173c1d9 100644 --- a/cpus.c +++ b/cpus.c @@ -396,7 +396,7 @@ static void do_vm_stop(RunState state) pause_all_vcpus(); runstate_set(state); vm_state_notify(0, state); - qemu_aio_flush(); + bdrv_drain_all(); bdrv_flush_all(); monitor_protocol_event(QEVENT_STOP, NULL); } diff --git a/hw/ide/macio.c b/hw/ide/macio.c index 70b33422d2..c09d2e0a35 100644 --- a/hw/ide/macio.c +++ b/hw/ide/macio.c @@ -200,8 +200,9 @@ static void pmac_ide_flush(DBDMA_io *io) { MACIOIDEState *m = io->opaque; - if (m->aiocb) - qemu_aio_flush(); + if (m->aiocb) { + bdrv_drain_all(); + } } /* PowerMac IDE memory IO */ diff --git a/hw/ide/pci.c b/hw/ide/pci.c index 49b823df79..5078c0b565 100644 --- a/hw/ide/pci.c +++ b/hw/ide/pci.c @@ -309,7 +309,7 @@ void bmdma_cmd_writeb(BMDMAState *bm, uint32_t val) * aio operation with preadv/pwritev. */ if (bm->bus->dma->aiocb) { - qemu_aio_flush(); + bdrv_drain_all(); assert(bm->bus->dma->aiocb == NULL); assert((bm->status & BM_STATUS_DMAING) == 0); } diff --git a/hw/virtio-blk.c b/hw/virtio-blk.c index d6d1f87cda..4b0d113ba8 100644 --- a/hw/virtio-blk.c +++ b/hw/virtio-blk.c @@ -474,7 +474,7 @@ static void virtio_blk_reset(VirtIODevice *vdev) * This should cancel pending requests, but can't do nicely until there * are per-device request lists. */ - qemu_aio_flush(); + bdrv_drain_all(); } /* coalesce internal state, copy to pci i/o region 0 diff --git a/hw/xen_platform.c b/hw/xen_platform.c index 5e792f56f6..e62eaef7d1 100644 --- a/hw/xen_platform.c +++ b/hw/xen_platform.c @@ -120,7 +120,7 @@ static void platform_fixed_ioport_writew(void *opaque, uint32_t addr, uint32_t v devices, and bit 2 the non-primary-master IDE devices. */ if (val & UNPLUG_ALL_IDE_DISKS) { DPRINTF("unplug disks\n"); - qemu_aio_flush(); + bdrv_drain_all(); bdrv_flush_all(); pci_unplug_disks(s->pci_dev.bus); } diff --git a/qemu-io.c b/qemu-io.c index de26422fcf..b35adbb00f 100644 --- a/qemu-io.c +++ b/qemu-io.c @@ -1853,9 +1853,9 @@ int main(int argc, char **argv) command_loop(); /* - * Make sure all outstanding requests get flushed the program exits. + * Make sure all outstanding requests complete before the program exits. */ - qemu_aio_flush(); + bdrv_drain_all(); if (bs) { bdrv_delete(bs); diff --git a/savevm.c b/savevm.c index f53cd4c154..0443554b39 100644 --- a/savevm.c +++ b/savevm.c @@ -2104,7 +2104,7 @@ int load_vmstate(const char *name) } /* Flush all IO requests so they don't interfere with the new state. */ - qemu_aio_flush(); + bdrv_drain_all(); bs = NULL; while ((bs = bdrv_next(bs))) { diff --git a/xen-mapcache.c b/xen-mapcache.c index 7bcb86e4f8..9fecc64e97 100644 --- a/xen-mapcache.c +++ b/xen-mapcache.c @@ -351,7 +351,7 @@ void xen_invalidate_map_cache(void) MapCacheRev *reventry; /* Flush pending AIO before destroying the mapcache */ - qemu_aio_flush(); + bdrv_drain_all(); QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) { DPRINTF("There should be no locked mappings at this time, " -- cgit v1.2.1