Signed-off-by: Zhi Yong Wu <wuzhy@xxxxxxxxxxxxxxxxxx> --- Makefile.objs | 2 +- block/blk-queue.c | 184 +++++++++++++++++++++++++++++++++++++++++++++++++++++ block/blk-queue.h | 59 +++++++++++++++++ 3 files changed, 244 insertions(+), 1 deletions(-) create mode 100644 block/blk-queue.c create mode 100644 block/blk-queue.h diff --git a/Makefile.objs b/Makefile.objs index d1f3e5d..96a7323 100644 --- a/Makefile.objs +++ b/Makefile.objs @@ -33,7 +33,7 @@ block-nested-y += raw.o cow.o qcow.o vdi.o vmdk.o cloop.o dmg.o bochs.o vpc.o vv block-nested-y += qcow2.o qcow2-refcount.o qcow2-cluster.o qcow2-snapshot.o qcow2-cache.o block-nested-y += qed.o qed-gencb.o qed-l2-cache.o qed-table.o qed-cluster.o block-nested-y += qed-check.o -block-nested-y += parallels.o nbd.o blkdebug.o sheepdog.o blkverify.o +block-nested-y += parallels.o nbd.o blkdebug.o sheepdog.o blkverify.o blk-queue.o block-nested-$(CONFIG_WIN32) += raw-win32.o block-nested-$(CONFIG_POSIX) += raw-posix.o block-nested-$(CONFIG_CURL) += curl.o diff --git a/block/blk-queue.c b/block/blk-queue.c new file mode 100644 index 0000000..da01fcb --- /dev/null +++ b/block/blk-queue.c @@ -0,0 +1,184 @@ +/* + * QEMU System Emulator queue definition for block layer + * + * Copyright (c) IBM, Corp. 2011 + * + * Authors: + * Zhi Yong Wu <wuzhy@xxxxxxxxxxxxxxxxxx> + * Stefan Hajnoczi <stefanha@xxxxxxxxxxxxxxxxxx> + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#include "block_int.h" +#include "block/blk-queue.h" +#include "qemu-common.h" + +/* The APIs for block request queue on qemu block layer. + */ + +struct BlockQueueAIOCB { + BlockDriverAIOCB common; + QTAILQ_ENTRY(BlockQueueAIOCB) entry; + BlockRequestHandler *handler; + BlockDriverAIOCB *real_acb; + + int64_t sector_num; + QEMUIOVector *qiov; + int nb_sectors; +}; + +typedef struct BlockQueueAIOCB BlockQueueAIOCB; + +struct BlockQueue { + QTAILQ_HEAD(requests, BlockQueueAIOCB) requests; + bool flushing; +}; + +static void qemu_block_queue_dequeue(BlockQueue *queue, + BlockQueueAIOCB *request) +{ + BlockQueueAIOCB *req; + + assert(queue); + while (!QTAILQ_EMPTY(&queue->requests)) { + req = QTAILQ_FIRST(&queue->requests); + if (req == request) { + QTAILQ_REMOVE(&queue->requests, req, entry); + break; + } + } +} + +static void qemu_block_queue_cancel(BlockDriverAIOCB *acb) +{ + BlockQueueAIOCB *request = container_of(acb, BlockQueueAIOCB, common); + if (request->real_acb) { + bdrv_aio_cancel(request->real_acb); + } else { + assert(request->common.bs->block_queue); + qemu_block_queue_dequeue(request->common.bs->block_queue, + request); + } + + qemu_aio_release(request); +} + +static AIOPool block_queue_pool = { + .aiocb_size = sizeof(struct BlockQueueAIOCB), + .cancel = qemu_block_queue_cancel, +}; + +BlockQueue *qemu_new_block_queue(void) +{ + BlockQueue *queue; + + queue = g_malloc0(sizeof(BlockQueue)); + + QTAILQ_INIT(&queue->requests); + + queue->flushing = false; + + return queue; +} + +void qemu_del_block_queue(BlockQueue *queue) +{ + BlockQueueAIOCB *request, *next; + + QTAILQ_FOREACH_SAFE(request, &queue->requests, entry, next) { + QTAILQ_REMOVE(&queue->requests, request, entry); + qemu_aio_release(request); + } + + g_free(queue); +} + +BlockDriverAIOCB *qemu_block_queue_enqueue(BlockQueue *queue, + BlockDriverState *bs, + BlockRequestHandler *handler, + int64_t sector_num, + QEMUIOVector *qiov, + int nb_sectors, + BlockDriverCompletionFunc *cb, + void *opaque) +{ + BlockDriverAIOCB *acb; + BlockQueueAIOCB *request; + + if (queue->flushing) { + return NULL; + } else { + acb = qemu_aio_get(&block_queue_pool, bs, + cb, opaque); + request = container_of(acb, BlockQueueAIOCB, common); + request->handler = handler; + request->sector_num = sector_num; + request->qiov = qiov; + request->nb_sectors = nb_sectors; + request->real_acb = NULL; + QTAILQ_INSERT_TAIL(&queue->requests, request, entry); + } + + return acb; +} + +static int qemu_block_queue_handler(BlockQueueAIOCB *request) +{ + int ret; + BlockDriverAIOCB *res; + + res = request->handler(request->common.bs, request->sector_num, + request->qiov, request->nb_sectors, + request->common.cb, request->common.opaque); + if (res) { + request->real_acb = res; + } + + ret = (res == NULL) ? 0 : 1; + + return ret; +} + +void qemu_block_queue_flush(BlockQueue *queue) +{ + queue->flushing = true; + while (!QTAILQ_EMPTY(&queue->requests)) { + BlockQueueAIOCB *request = NULL; + int ret = 0; + + request = QTAILQ_FIRST(&queue->requests); + QTAILQ_REMOVE(&queue->requests, request, entry); + + ret = qemu_block_queue_handler(request); + if (ret == 0) { + QTAILQ_INSERT_HEAD(&queue->requests, request, entry); + break; + } + + qemu_aio_release(request); + } + + queue->flushing = false; +} + +bool qemu_block_queue_has_pending(BlockQueue *queue) +{ + return !queue->flushing && !QTAILQ_EMPTY(&queue->requests); +} diff --git a/block/blk-queue.h b/block/blk-queue.h new file mode 100644 index 0000000..c1529f7 --- /dev/null +++ b/block/blk-queue.h @@ -0,0 +1,59 @@ +/* + * QEMU System Emulator queue declaration for block layer + * + * Copyright (c) IBM, Corp. 2011 + * + * Authors: + * Zhi Yong Wu <wuzhy@xxxxxxxxxxxxxxxxxx> + * Stefan Hajnoczi <stefanha@xxxxxxxxxxxxxxxxxx> + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#ifndef QEMU_BLOCK_QUEUE_H +#define QEMU_BLOCK_QUEUE_H + +#include "block.h" +#include "qemu-queue.h" + +typedef BlockDriverAIOCB* (BlockRequestHandler) (BlockDriverState *bs, + int64_t sector_num, QEMUIOVector *qiov, + int nb_sectors, BlockDriverCompletionFunc *cb, + void *opaque); + +typedef struct BlockQueue BlockQueue; + +BlockQueue *qemu_new_block_queue(void); + +void qemu_del_block_queue(BlockQueue *queue); + +BlockDriverAIOCB *qemu_block_queue_enqueue(BlockQueue *queue, + BlockDriverState *bs, + BlockRequestHandler *handler, + int64_t sector_num, + QEMUIOVector *qiov, + int nb_sectors, + BlockDriverCompletionFunc *cb, + void *opaque); + +void qemu_block_queue_flush(BlockQueue *queue); + +bool qemu_block_queue_has_pending(BlockQueue *queue); + +#endif /* QEMU_BLOCK_QUEUE_H */ -- 1.7.6 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html