raw-win32: add emulated AIO support (fc4edb84) · Commits · SUMMER2020 / students / proj-2021291

block/raw-win32.c

+138 −49

Original line number	Diff line number	Diff line
		@@ -25,6 +25,10 @@
		#include "qemu-timer.h"
		#include "block_int.h"
		#include "module.h"
		#include "raw-aio.h"
		#include "trace.h"
		#include "thread-pool.h"
		#include "iov.h"
		#include <windows.h>
		#include <winioctl.h>

		@@ -32,12 +36,127 @@
		#define FTYPE_CD 1
		#define FTYPE_HARDDISK 2

		typedef struct RawWin32AIOData {
		BlockDriverState *bs;
		HANDLE hfile;
		struct iovec *aio_iov;
		int aio_niov;
		size_t aio_nbytes;
		off64_t aio_offset;
		int aio_type;
		} RawWin32AIOData;

		typedef struct BDRVRawState {
		HANDLE hfile;
		int type;
		char drive_path[16]; /* format: "d:\" */
		} BDRVRawState;

		/*
		* Read/writes the data to/from a given linear buffer.
		*
		* Returns the number of bytes handles or -errno in case of an error. Short
		* reads are only returned if the end of the file is reached.
		*/
		static size_t handle_aiocb_rw(RawWin32AIOData *aiocb)
		{
		size_t offset = 0;
		int i;

		for (i = 0; i < aiocb->aio_niov; i++) {
		OVERLAPPED ov;
		DWORD ret, ret_count, len;

		memset(&ov, 0, sizeof(ov));
		ov.Offset = (aiocb->aio_offset + offset);
		ov.OffsetHigh = (aiocb->aio_offset + offset) >> 32;
		len = aiocb->aio_iov[i].iov_len;
		if (aiocb->aio_type & QEMU_AIO_WRITE) {
		ret = WriteFile(aiocb->hfile, aiocb->aio_iov[i].iov_base,
		len, &ret_count, &ov);
		} else {
		ret = ReadFile(aiocb->hfile, aiocb->aio_iov[i].iov_base,
		len, &ret_count, &ov);
		}
		if (!ret) {
		ret_count = 0;
		}
		if (ret_count != len) {
		break;
		}
		offset += len;
		}

		return offset;
		}

		static int aio_worker(void *arg)
		{
		RawWin32AIOData *aiocb = arg;
		ssize_t ret = 0;
		size_t count;

		switch (aiocb->aio_type & QEMU_AIO_TYPE_MASK) {
		case QEMU_AIO_READ:
		count = handle_aiocb_rw(aiocb);
		if (count < aiocb->aio_nbytes && aiocb->bs->growable) {
		/* A short read means that we have reached EOF. Pad the buffer
		* with zeros for bytes after EOF. */
		iov_memset(aiocb->aio_iov, aiocb->aio_niov, count,
		0, aiocb->aio_nbytes - count);

		count = aiocb->aio_nbytes;
		}
		if (count == aiocb->aio_nbytes) {
		ret = 0;
		} else {
		ret = -EINVAL;
		}
		break;
		case QEMU_AIO_WRITE:
		count = handle_aiocb_rw(aiocb);
		if (count == aiocb->aio_nbytes) {
		count = 0;
		} else {
		count = -EINVAL;
		}
		break;
		case QEMU_AIO_FLUSH:
		if (!FlushFileBuffers(aiocb->hfile)) {
		return -EIO;
		}
		break;
		default:
		fprintf(stderr, "invalid aio request (0x%x)\n", aiocb->aio_type);
		ret = -EINVAL;
		break;
		}

		g_slice_free(RawWin32AIOData, aiocb);
		return ret;
		}

		static BlockDriverAIOCB paio_submit(BlockDriverState bs, HANDLE hfile,
		int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
		BlockDriverCompletionFunc cb, void opaque, int type)
		{
		RawWin32AIOData *acb = g_slice_new(RawWin32AIOData);

		acb->bs = bs;
		acb->hfile = hfile;
		acb->aio_type = type;

		if (qiov) {
		acb->aio_iov = qiov->iov;
		acb->aio_niov = qiov->niov;
		}
		acb->aio_nbytes = nb_sectors * 512;
		acb->aio_offset = sector_num * 512;

		trace_paio_submit(acb, opaque, sector_num, nb_sectors, type);
		return thread_pool_submit_aio(aio_worker, acb, cb, opaque);
		}

		int qemu_ftruncate64(int fd, int64_t length)
		{
		LARGE_INTEGER li;
		@@ -117,59 +236,29 @@ static int raw_open(BlockDriverState bs, const char filename, int flags)
		return 0;
		}

		static int raw_read(BlockDriverState *bs, int64_t sector_num,
		uint8_t *buf, int nb_sectors)
		static BlockDriverAIOCB raw_aio_readv(BlockDriverState bs,
		int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
		BlockDriverCompletionFunc cb, void opaque)
		{
		BDRVRawState *s = bs->opaque;
		OVERLAPPED ov;
		DWORD ret_count;
		int ret;
		int64_t offset = sector_num * 512;
		int count = nb_sectors * 512;

		memset(&ov, 0, sizeof(ov));
		ov.Offset = offset;
		ov.OffsetHigh = offset >> 32;
		ret = ReadFile(s->hfile, buf, count, &ret_count, &ov);
		if (!ret)
		return ret_count;
		if (ret_count == count)
		ret_count = 0;
		return ret_count;
		return paio_submit(bs, s->hfile, sector_num, qiov, nb_sectors,
		cb, opaque, QEMU_AIO_READ);
		}

		static int raw_write(BlockDriverState *bs, int64_t sector_num,
		const uint8_t *buf, int nb_sectors)
		static BlockDriverAIOCB raw_aio_writev(BlockDriverState bs,
		int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
		BlockDriverCompletionFunc cb, void opaque)
		{
		BDRVRawState *s = bs->opaque;
		OVERLAPPED ov;
		DWORD ret_count;
		int ret;
		int64_t offset = sector_num * 512;
		int count = nb_sectors * 512;

		memset(&ov, 0, sizeof(ov));
		ov.Offset = offset;
		ov.OffsetHigh = offset >> 32;
		ret = WriteFile(s->hfile, buf, count, &ret_count, &ov);
		if (!ret)
		return ret_count;
		if (ret_count == count)
		ret_count = 0;
		return ret_count;
		return paio_submit(bs, s->hfile, sector_num, qiov, nb_sectors,
		cb, opaque, QEMU_AIO_WRITE);
		}

		static int raw_flush(BlockDriverState *bs)
		static BlockDriverAIOCB raw_aio_flush(BlockDriverState bs,
		BlockDriverCompletionFunc cb, void opaque)
		{
		BDRVRawState *s = bs->opaque;
		int ret;

		ret = FlushFileBuffers(s->hfile);
		if (ret == 0) {
		return -EIO;
		}

		return 0;
		return paio_submit(bs, s->hfile, 0, NULL, 0, cb, opaque, QEMU_AIO_FLUSH);
		}

		static void raw_close(BlockDriverState *bs)
		@@ -290,9 +379,9 @@ static BlockDriver bdrv_file = {
		.bdrv_close = raw_close,
		.bdrv_create = raw_create,

		.bdrv_read = raw_read,
		.bdrv_write = raw_write,
		.bdrv_co_flush_to_disk = raw_flush,
		.bdrv_aio_readv = raw_aio_readv,
		.bdrv_aio_writev = raw_aio_writev,
		.bdrv_aio_flush = raw_aio_flush,

		.bdrv_truncate = raw_truncate,
		.bdrv_getlength = raw_getlength,
		@@ -413,9 +502,9 @@ static BlockDriver bdrv_host_device = {
		.bdrv_close = raw_close,
		.bdrv_has_zero_init = hdev_has_zero_init,

		.bdrv_read = raw_read,
		.bdrv_write = raw_write,
		.bdrv_co_flush_to_disk = raw_flush,
		.bdrv_aio_readv = raw_aio_readv,
		.bdrv_aio_writev = raw_aio_writev,
		.bdrv_aio_flush = raw_aio_flush,

		.bdrv_getlength = raw_getlength,
		.bdrv_get_allocated_file_size