diff options
Diffstat (limited to 'block/io.c')
| -rw-r--r-- | block/io.c | 175 |
1 files changed, 145 insertions, 30 deletions
diff --git a/block/io.c b/block/io.c index 5ac6256ad3..e00fb5d690 100644 --- a/block/io.c +++ b/block/io.c @@ -216,6 +216,8 @@ void bdrv_disable_copy_on_read(BlockDriverState *bs) /* Check if any requests are in-flight (including throttled requests) */ bool bdrv_requests_pending(BlockDriverState *bs) { + BdrvChild *child; + if (!QLIST_EMPTY(&bs->tracked_requests)) { return true; } @@ -225,17 +227,31 @@ bool bdrv_requests_pending(BlockDriverState *bs) if (!qemu_co_queue_empty(&bs->throttled_reqs[1])) { return true; } - if (bs->file && bdrv_requests_pending(bs->file->bs)) { - return true; - } - if (bs->backing && bdrv_requests_pending(bs->backing->bs)) { - return true; + + QLIST_FOREACH(child, &bs->children, next) { + if (bdrv_requests_pending(child->bs)) { + return true; + } } + return false; } +static void bdrv_drain_recurse(BlockDriverState *bs) +{ + BdrvChild *child; + + if (bs->drv && bs->drv->bdrv_drain) { + bs->drv->bdrv_drain(bs); + } + QLIST_FOREACH(child, &bs->children, next) { + bdrv_drain_recurse(child->bs); + } +} + /* - * Wait for pending requests to complete on a single BlockDriverState subtree + * Wait for pending requests to complete on a single BlockDriverState subtree, + * and suspend block driver's internal I/O until next request arrives. * * Note that unlike bdrv_drain_all(), the caller must hold the BlockDriverState * AioContext. @@ -248,6 +264,7 @@ void bdrv_drain(BlockDriverState *bs) { bool busy = true; + bdrv_drain_recurse(bs); while (busy) { /* Keep iterating */ bdrv_flush_io_queue(bs); @@ -345,13 +362,14 @@ static void tracked_request_end(BdrvTrackedRequest *req) static void tracked_request_begin(BdrvTrackedRequest *req, BlockDriverState *bs, int64_t offset, - unsigned int bytes, bool is_write) + unsigned int bytes, + enum BdrvTrackedRequestType type) { *req = (BdrvTrackedRequest){ .bs = bs, .offset = offset, .bytes = bytes, - .is_write = is_write, + .type = type, .co = qemu_coroutine_self(), .serialising = false, .overlap_offset = offset, @@ -845,7 +863,9 @@ static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs, mark_request_serialising(req, bdrv_get_cluster_size(bs)); } - wait_serialising_requests(req); + if (!(flags & BDRV_REQ_NO_SERIALISING)) { + wait_serialising_requests(req); + } if (flags & BDRV_REQ_COPY_ON_READ) { int pnum; @@ -934,7 +954,7 @@ static int coroutine_fn bdrv_co_do_preadv(BlockDriverState *bs, } /* Don't do copy-on-read if we read data before write operation */ - if (bs->copy_on_read && !(flags & BDRV_REQ_NO_COPY_ON_READ)) { + if (bs->copy_on_read && !(flags & BDRV_REQ_NO_SERIALISING)) { flags |= BDRV_REQ_COPY_ON_READ; } @@ -968,7 +988,7 @@ static int coroutine_fn bdrv_co_do_preadv(BlockDriverState *bs, bytes = ROUND_UP(bytes, align); } - tracked_request_begin(&req, bs, offset, bytes, false); + tracked_request_begin(&req, bs, offset, bytes, BDRV_TRACKED_READ); ret = bdrv_aligned_preadv(bs, &req, offset, bytes, align, use_local_qiov ? &local_qiov : qiov, flags); @@ -1003,13 +1023,13 @@ int coroutine_fn bdrv_co_readv(BlockDriverState *bs, int64_t sector_num, return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, 0); } -int coroutine_fn bdrv_co_no_copy_on_readv(BlockDriverState *bs, +int coroutine_fn bdrv_co_readv_no_serialising(BlockDriverState *bs, int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) { - trace_bdrv_co_no_copy_on_readv(bs, sector_num, nb_sectors); + trace_bdrv_co_readv_no_serialising(bs, sector_num, nb_sectors); return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, - BDRV_REQ_NO_COPY_ON_READ); + BDRV_REQ_NO_SERIALISING); } int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs, @@ -1289,7 +1309,7 @@ static int coroutine_fn bdrv_co_do_pwritev(BlockDriverState *bs, * Pad qiov with the read parts and be sure to have a tracked request not * only for bdrv_aligned_pwritev, but also for the reads of the RMW cycle. */ - tracked_request_begin(&req, bs, offset, bytes, true); + tracked_request_begin(&req, bs, offset, bytes, BDRV_TRACKED_WRITE); if (!qiov) { ret = bdrv_co_do_zero_pwritev(bs, offset, bytes, flags, &req); @@ -2314,18 +2334,20 @@ static void coroutine_fn bdrv_flush_co_entry(void *opaque) int coroutine_fn bdrv_co_flush(BlockDriverState *bs) { int ret; + BdrvTrackedRequest req; if (!bs || !bdrv_is_inserted(bs) || bdrv_is_read_only(bs) || bdrv_is_sg(bs)) { return 0; } + tracked_request_begin(&req, bs, 0, 0, BDRV_TRACKED_FLUSH); /* Write back cached data to the OS even with cache=unsafe */ BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_OS); if (bs->drv->bdrv_co_flush_to_os) { ret = bs->drv->bdrv_co_flush_to_os(bs); if (ret < 0) { - return ret; + goto out; } } @@ -2365,14 +2387,17 @@ int coroutine_fn bdrv_co_flush(BlockDriverState *bs) ret = 0; } if (ret < 0) { - return ret; + goto out; } /* Now flush the underlying protocol. It will also have BDRV_O_NO_FLUSH * in the case of cache=unsafe, so there are no useless flushes. */ flush_parent: - return bs->file ? bdrv_co_flush(bs->file->bs) : 0; + ret = bs->file ? bdrv_co_flush(bs->file->bs) : 0; +out: + tracked_request_end(&req); + return ret; } int bdrv_flush(BlockDriverState *bs) @@ -2415,6 +2440,7 @@ static void coroutine_fn bdrv_discard_co_entry(void *opaque) int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors) { + BdrvTrackedRequest req; int max_discard, ret; if (!bs->drv) { @@ -2437,6 +2463,8 @@ int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, return 0; } + tracked_request_begin(&req, bs, sector_num, nb_sectors, + BDRV_TRACKED_DISCARD); bdrv_set_dirty(bs, sector_num, nb_sectors); max_discard = MIN_NON_ZERO(bs->bl.max_discard, BDRV_REQUEST_MAX_SECTORS); @@ -2470,20 +2498,24 @@ int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, acb = bs->drv->bdrv_aio_discard(bs, sector_num, nb_sectors, bdrv_co_io_em_complete, &co); if (acb == NULL) { - return -EIO; + ret = -EIO; + goto out; } else { qemu_coroutine_yield(); ret = co.ret; } } if (ret && ret != -ENOTSUP) { - return ret; + goto out; } sector_num += num; nb_sectors -= num; } - return 0; + ret = 0; +out: + tracked_request_end(&req); + return ret; } int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors) @@ -2512,26 +2544,109 @@ int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors) return rwco.ret; } -/* needed for generic scsi interface */ +typedef struct { + CoroutineIOCompletion *co; + QEMUBH *bh; +} BdrvIoctlCompletionData; -int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf) +static void bdrv_ioctl_bh_cb(void *opaque) +{ + BdrvIoctlCompletionData *data = opaque; + + bdrv_co_io_em_complete(data->co, -ENOTSUP); + qemu_bh_delete(data->bh); +} + +static int bdrv_co_do_ioctl(BlockDriverState *bs, int req, void *buf) { BlockDriver *drv = bs->drv; + BdrvTrackedRequest tracked_req; + CoroutineIOCompletion co = { + .coroutine = qemu_coroutine_self(), + }; + BlockAIOCB *acb; - if (drv && drv->bdrv_ioctl) - return drv->bdrv_ioctl(bs, req, buf); - return -ENOTSUP; + tracked_request_begin(&tracked_req, bs, 0, 0, BDRV_TRACKED_IOCTL); + if (!drv || !drv->bdrv_aio_ioctl) { + co.ret = -ENOTSUP; + goto out; + } + + acb = drv->bdrv_aio_ioctl(bs, req, buf, bdrv_co_io_em_complete, &co); + if (!acb) { + BdrvIoctlCompletionData *data = g_new(BdrvIoctlCompletionData, 1); + data->bh = aio_bh_new(bdrv_get_aio_context(bs), + bdrv_ioctl_bh_cb, data); + data->co = &co; + qemu_bh_schedule(data->bh); + } + qemu_coroutine_yield(); +out: + tracked_request_end(&tracked_req); + return co.ret; +} + +typedef struct { + BlockDriverState *bs; + int req; + void *buf; + int ret; +} BdrvIoctlCoData; + +static void coroutine_fn bdrv_co_ioctl_entry(void *opaque) +{ + BdrvIoctlCoData *data = opaque; + data->ret = bdrv_co_do_ioctl(data->bs, data->req, data->buf); +} + +/* needed for generic scsi interface */ +int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf) +{ + BdrvIoctlCoData data = { + .bs = bs, + .req = req, + .buf = buf, + .ret = -EINPROGRESS, + }; + + if (qemu_in_coroutine()) { + /* Fast-path if already in coroutine context */ + bdrv_co_ioctl_entry(&data); + } else { + Coroutine *co = qemu_coroutine_create(bdrv_co_ioctl_entry); + qemu_coroutine_enter(co, &data); + } + while (data.ret == -EINPROGRESS) { + aio_poll(bdrv_get_aio_context(bs), true); + } + return data.ret; +} + +static void coroutine_fn bdrv_co_aio_ioctl_entry(void *opaque) +{ + BlockAIOCBCoroutine *acb = opaque; + acb->req.error = bdrv_co_do_ioctl(acb->common.bs, + acb->req.req, acb->req.buf); + bdrv_co_complete(acb); } BlockAIOCB *bdrv_aio_ioctl(BlockDriverState *bs, unsigned long int req, void *buf, BlockCompletionFunc *cb, void *opaque) { - BlockDriver *drv = bs->drv; + BlockAIOCBCoroutine *acb = qemu_aio_get(&bdrv_em_co_aiocb_info, + bs, cb, opaque); + Coroutine *co; + + acb->need_bh = true; + acb->req.error = -EINPROGRESS; + acb->req.req = req; + acb->req.buf = buf; + co = qemu_coroutine_create(bdrv_co_aio_ioctl_entry); + qemu_coroutine_enter(co, acb); - if (drv && drv->bdrv_aio_ioctl) - return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque); - return NULL; + bdrv_co_maybe_schedule_bh(acb); + return &acb->common; } void *qemu_blockalign(BlockDriverState *bs, size_t size) |