[fio.git] / engines / windowsaio.c

/*
 * Native Windows async IO engine
 * Copyright (C) 2011 Bruce Cran <bruce@cran.org.uk>
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <errno.h>
#include <windows.h>

#include "../fio.h"

typedef BOOL (WINAPI *CANCELIOEX)(HANDLE hFile, LPOVERLAPPED lpOverlapped);

struct fio_overlapped {
	OVERLAPPED o;
	struct io_u *io_u;
	BOOL io_complete;
    BOOL io_free;
};

struct windowsaio_data {
	struct fio_overlapped *ovls;
	struct io_u **aio_events;
	HANDLE iothread;
	HANDLE iocomplete_event;
	CANCELIOEX pCancelIoEx;
	BOOL iothread_running;
};

struct thread_ctx {
	HANDLE iocp;
	struct windowsaio_data *wd;
};

static int fio_windowsaio_cancel(struct thread_data *td,
			       struct io_u *io_u);
static BOOL timeout_expired(DWORD start_count, DWORD end_count);
static int fio_windowsaio_getevents(struct thread_data *td, unsigned int min,
				    unsigned int max, struct timespec *t);
static struct io_u *fio_windowsaio_event(struct thread_data *td, int event);
static int fio_windowsaio_queue(struct thread_data *td,
			      struct io_u *io_u);
static void fio_windowsaio_cleanup(struct thread_data *td);
static DWORD WINAPI IoCompletionRoutine(LPVOID lpParameter);
static int fio_windowsaio_init(struct thread_data *td);
static int fio_windowsaio_open_file(struct thread_data *td, struct fio_file *f);
static int fio_windowsaio_close_file(struct thread_data fio_unused *td, struct fio_file *f);

int sync_file_range(int fd, off64_t offset, off64_t nbytes,
			   unsigned int flags)
{
	errno = ENOSYS;
	return -1;
}

static int fio_windowsaio_init(struct thread_data *td)
{
	struct windowsaio_data *wd;
	HANDLE hKernel32Dll;
	int rc = 0;
	int i;

	wd = malloc(sizeof(struct windowsaio_data));
	if (wd != NULL)
		ZeroMemory(wd, sizeof(struct windowsaio_data));
	else
		rc = 1;

	if (!rc) {
		wd->aio_events = malloc(td->o.iodepth * sizeof(struct io_u*));
		if (wd->aio_events == NULL)
			rc = 1;
	}

	if (!rc) {
		wd->ovls = malloc(td->o.iodepth * sizeof(struct fio_overlapped));
		if (wd->ovls == NULL)
			rc = 1;
	}

	if (!rc) {
	    for (i = 0; i < td->o.iodepth; i++) {
	        wd->ovls[i].io_free = TRUE;
	        wd->ovls[i].io_complete = FALSE;

			wd->ovls[i].o.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
			if (wd->ovls[i].o.hEvent == NULL) {
				rc = 1;
				break;
			}
	    }
	}

	if (!rc) {
		/* Create an auto-reset event */
		wd->iocomplete_event = CreateEvent(NULL, FALSE, FALSE, NULL);
		if (wd->iocomplete_event == NULL)
			rc = 1;
	}

	if (rc) {
		if (wd != NULL) {
			if (wd->ovls != NULL)
				free(wd->ovls);
			if (wd->aio_events != NULL)
				free(wd->aio_events);

			free(wd);
		}
	}

	hKernel32Dll = GetModuleHandle("kernel32.dll");
	wd->pCancelIoEx = GetProcAddress(hKernel32Dll, "CancelIoEx");

	td->io_ops->data = wd;
	return rc;
}

static void fio_windowsaio_cleanup(struct thread_data *td)
{
	int i;
	struct windowsaio_data *wd;

	wd = td->io_ops->data;

	if (wd != NULL) {
	    wd->iothread_running = FALSE;
    	WaitForSingleObject(wd->iothread, INFINITE);

		CloseHandle(wd->iothread);
		CloseHandle(wd->iocomplete_event);

		for (i = 0; i < td->o.iodepth; i++) {
			CloseHandle(wd->ovls[i].o.hEvent);
		}

		free(wd->aio_events);
		free(wd->ovls);
		free(wd);

		td->io_ops->data = NULL;
	}
}


static int fio_windowsaio_open_file(struct thread_data *td, struct fio_file *f)
{
	int rc = 0;
	HANDLE hFile;
	DWORD flags = FILE_FLAG_POSIX_SEMANTICS | FILE_FLAG_OVERLAPPED;
	DWORD sharemode = FILE_SHARE_READ | FILE_SHARE_WRITE;
	DWORD openmode = OPEN_ALWAYS;
	DWORD access;

	dprint(FD_FILE, "fd open %s\n", f->file_name);

	if (f->filetype == FIO_TYPE_PIPE) {
		log_err("fio: windowsaio doesn't support pipes\n");
		return 1;
	}

	if (!strcmp(f->file_name, "-")) {
		log_err("fio: can't read/write to stdin/out\n");
		return 1;
	}

	if (td->o.odirect)
		flags |= FILE_FLAG_NO_BUFFERING;
	if (td->o.sync_io)
		flags |= FILE_FLAG_WRITE_THROUGH;

	if (td->o.td_ddir == TD_DDIR_READ  ||
		td->o.td_ddir == TD_DDIR_WRITE)
		flags |= FILE_FLAG_SEQUENTIAL_SCAN;
	else
		flags |= FILE_FLAG_RANDOM_ACCESS;

	if (!td_write(td) || read_only)
		access = GENERIC_READ;
	else
		access = (GENERIC_READ | GENERIC_WRITE);

	if (td->o.create_on_open > 0)
		openmode = OPEN_ALWAYS;
	else
		openmode = OPEN_EXISTING;

	f->hFile = CreateFile(f->file_name, access, sharemode,
		NULL, openmode, flags, NULL);

	if (f->hFile == INVALID_HANDLE_VALUE)
		rc = 1;

	/* Only set up the competion port and thread if we're not just
	 * querying the device size */
    if (!rc && td->io_ops->data != NULL) {
		struct thread_ctx *ctx;
        struct windowsaio_data *wd;
		hFile = CreateIoCompletionPort(f->hFile, NULL, 0, 0);

        wd = td->io_ops->data;

		wd->iothread_running = TRUE;

		if (!rc) {
			ctx = malloc(sizeof(struct thread_ctx));
			ctx->iocp = hFile;
			ctx->wd = wd;

			wd->iothread = CreateThread(NULL, 0, IoCompletionRoutine, ctx, 0, NULL);
		}

		if (rc || wd->iothread == NULL)
			rc = 1;
	}

	return rc;
}

static int fio_windowsaio_close_file(struct thread_data fio_unused *td, struct fio_file *f)
{
	int rc = 0;
	
	dprint(FD_FILE, "fd close %s\n", f->file_name);

	if (f->hFile != INVALID_HANDLE_VALUE) {
		if (!CloseHandle(f->hFile))
			rc = 1;
	}

	f->hFile = INVALID_HANDLE_VALUE;
	return rc;
}

static BOOL timeout_expired(DWORD start_count, DWORD end_count)
{
	BOOL expired = FALSE;
	DWORD current_time;

	current_time = GetTickCount();

	if ((end_count > start_count) && current_time >= end_count)
		expired = TRUE;
	else if (current_time < start_count && current_time > end_count)
		expired = TRUE;

	return expired;
}

static struct io_u* fio_windowsaio_event(struct thread_data *td, int event)
{
	struct windowsaio_data *wd = td->io_ops->data;
	return wd->aio_events[event];
}

static int fio_windowsaio_getevents(struct thread_data *td, unsigned int min,
				    unsigned int max, struct timespec *t)
{
	struct windowsaio_data *wd = td->io_ops->data;
	struct flist_head *entry;
	unsigned int dequeued = 0;
	struct io_u *io_u;
	struct fio_overlapped *fov;
	DWORD start_count = 0;
	DWORD end_count = 0;
	DWORD status;
	DWORD mswait = 250;

	if (t != NULL) {
		mswait = (t->tv_sec * 1000) + (t->tv_nsec / 1000000);
		start_count = GetTickCount();
		end_count = start_count + (t->tv_sec * 1000) + (t->tv_nsec / 1000000);
	}

	do {
		flist_for_each(entry, &td->io_u_busylist) {
			io_u = flist_entry(entry, struct io_u, list);
			fov = (struct fio_overlapped*)io_u->engine_data;

			if (fov->io_complete) {
                fov->io_complete = FALSE;
				fov->io_free  = TRUE;
				wd->aio_events[dequeued] = io_u;
				dequeued++;
			}

			if (dequeued >= min)
				break;
		}

        if (dequeued < min) {
			status = WaitForSingleObject(wd->iocomplete_event, mswait);
			if (status != WAIT_OBJECT_0 && dequeued > 0)
			    break;
		}

		if (dequeued >= min || (t != NULL && timeout_expired(start_count, end_count)))
			break;
	} while (1);

	return dequeued;
}

static int fio_windowsaio_queue(struct thread_data *td,
			      struct io_u *io_u)
{
    LPOVERLAPPED lpOvl = NULL;
	struct windowsaio_data *wd;
	DWORD iobytes;
	BOOL success;
	int index;
	int rc = FIO_Q_COMPLETED;

	fio_ro_check(td, io_u);

	wd = td->io_ops->data;

    for (index = 0; index < td->o.iodepth; index++) {
        if (wd->ovls[index].io_free) {
            wd->ovls[index].io_free = FALSE;
            ResetEvent(wd->ovls[index].o.hEvent);
            break;
        }
    }

    assert(index < td->o.iodepth);

    lpOvl = &wd->ovls[index].o;
    wd->ovls[index].io_u = io_u;
	lpOvl->Internal = STATUS_PENDING;
	lpOvl->InternalHigh = 0;
	lpOvl->Offset = io_u->offset & 0xFFFFFFFF;
	lpOvl->OffsetHigh = io_u->offset >> 32;
	lpOvl->Pointer = NULL;
    io_u->engine_data = &wd->ovls[index];

	switch (io_u->ddir) {
    case DDIR_WRITE:
		success = WriteFile(io_u->file->hFile, io_u->xfer_buf, io_u->xfer_buflen, &iobytes, lpOvl);
		break;
	case DDIR_READ:
		success = ReadFile(io_u->file->hFile, io_u->xfer_buf, io_u->xfer_buflen, &iobytes, lpOvl);
		break;
	case DDIR_SYNC:
	case DDIR_DATASYNC:
	case DDIR_SYNC_FILE_RANGE:
		success = FlushFileBuffers(io_u->file->hFile);
		if (!success)
		    io_u->error = GetLastError();

		return FIO_Q_COMPLETED;
		break;
	case DDIR_TRIM:
		log_err("manual TRIM isn't supported on Windows");
		io_u->error = 1;
		io_u->resid = io_u->xfer_buflen;
		return FIO_Q_COMPLETED;
		break;
	default:
		assert(0);
	}

    if (success || GetLastError() == ERROR_IO_PENDING) {
		rc = FIO_Q_QUEUED;
	} else {
		io_u->error = GetLastError();
		io_u->resid = io_u->xfer_buflen;
	}

	return rc;
}

/* Runs as a thread and waits for queued IO to complete */
static DWORD WINAPI IoCompletionRoutine(LPVOID lpParameter)
{
	OVERLAPPED *ovl;
	struct fio_overlapped *fov;
	struct io_u *io_u;
	struct windowsaio_data *wd;
	struct thread_ctx *ctx;
	ULONG_PTR ulKey = 0;
	DWORD bytes;

	ctx = (struct thread_ctx*)lpParameter;
	wd = ctx->wd;

	do {
		if (!GetQueuedCompletionStatus(ctx->iocp, &bytes, &ulKey, &ovl, 250))
			continue;

		fov = CONTAINING_RECORD(ovl, struct fio_overlapped, o);
		io_u = fov->io_u;

		if (ovl->Internal == ERROR_SUCCESS) {
			io_u->resid = io_u->xfer_buflen - ovl->InternalHigh;
			io_u->error = 0;
		} else {
			io_u->resid = io_u->xfer_buflen;
			io_u->error = ovl->Internal;
		}

        fov->io_complete = TRUE;
		SetEvent(wd->iocomplete_event);
	} while (ctx->wd->iothread_running);

	CloseHandle(ctx->iocp);
	free(ctx);
	return 0;
}

static int fio_windowsaio_cancel(struct thread_data *td,
			       struct io_u *io_u)
{
	int rc = 0;

	struct windowsaio_data *wd = td->io_ops->data;

	/* If we're running on Vista or newer, we can cancel individual IO requests */
	if (wd->pCancelIoEx != NULL) {
		struct fio_overlapped *ovl = io_u->engine_data;
		if (!wd->pCancelIoEx(io_u->file->hFile, &ovl->o))
			rc = 1;
	} else
		rc = 1;

	return rc;
}

static struct ioengine_ops ioengine = {
	.name		= "windowsaio",
	.version	= FIO_IOOPS_VERSION,
	.init		= fio_windowsaio_init,
	.queue		= fio_windowsaio_queue,
	.cancel		= fio_windowsaio_cancel,
	.getevents	= fio_windowsaio_getevents,
	.event		= fio_windowsaio_event,
	.cleanup	= fio_windowsaio_cleanup,
	.open_file	= fio_windowsaio_open_file,
	.close_file	= fio_windowsaio_close_file,
	.get_file_size	= generic_get_file_size
};

static void fio_init fio_posixaio_register(void)
{
	register_ioengine(&ioengine);
}

static void fio_exit fio_posixaio_unregister(void)
{
	unregister_ioengine(&ioengine);
}
Commit	Line	Data
	1	/*
	2	* Native Windows async IO engine
	3	* Copyright (C) 2011 Bruce Cran <bruce@cran.org.uk>
	4	*/
	5
	6	#include <stdio.h>
	7	#include <stdlib.h>
	8	#include <unistd.h>
	9	#include <signal.h>
	10	#include <errno.h>
	11	#include <windows.h>
	12
	13	#include "../fio.h"
	14
	15	typedef BOOL (WINAPI *CANCELIOEX)(HANDLE hFile, LPOVERLAPPED lpOverlapped);
	16
	17	struct fio_overlapped {
	18	OVERLAPPED o;
	19	struct io_u *io_u;
	20	BOOL io_complete;
	21	BOOL io_free;
	22	};
	23
	24	struct windowsaio_data {
	25	struct fio_overlapped *ovls;
	26	struct io_u **aio_events;
	27	HANDLE iothread;
	28	HANDLE iocomplete_event;
	29	CANCELIOEX pCancelIoEx;
	30	BOOL iothread_running;
	31	};
	32
	33	struct thread_ctx {
	34	HANDLE iocp;
	35	struct windowsaio_data *wd;
	36	};
	37
	38	static int fio_windowsaio_cancel(struct thread_data *td,
	39	struct io_u *io_u);
	40	static BOOL timeout_expired(DWORD start_count, DWORD end_count);
	41	static int fio_windowsaio_getevents(struct thread_data *td, unsigned int min,
	42	unsigned int max, struct timespec *t);
	43	static struct io_u fio_windowsaio_event(struct thread_data td, int event);
	44	static int fio_windowsaio_queue(struct thread_data *td,
	45	struct io_u *io_u);
	46	static void fio_windowsaio_cleanup(struct thread_data *td);
	47	static DWORD WINAPI IoCompletionRoutine(LPVOID lpParameter);
	48	static int fio_windowsaio_init(struct thread_data *td);
	49	static int fio_windowsaio_open_file(struct thread_data td, struct fio_file f);
	50	static int fio_windowsaio_close_file(struct thread_data fio_unused td, struct fio_file f);
	51
	52	int sync_file_range(int fd, off64_t offset, off64_t nbytes,
	53	unsigned int flags)
	54	{
	55	errno = ENOSYS;
	56	return -1;
	57	}
	58
	59	static int fio_windowsaio_init(struct thread_data *td)
	60	{
	61	struct windowsaio_data *wd;
	62	HANDLE hKernel32Dll;
	63	int rc = 0;
	64	int i;
	65
	66	wd = malloc(sizeof(struct windowsaio_data));
	67	if (wd != NULL)
	68	ZeroMemory(wd, sizeof(struct windowsaio_data));
	69	else
	70	rc = 1;
	71
	72	if (!rc) {
	73	wd->aio_events = malloc(td->o.iodepth * sizeof(struct io_u*));
	74	if (wd->aio_events == NULL)
	75	rc = 1;
	76	}
	77
	78	if (!rc) {
	79	wd->ovls = malloc(td->o.iodepth * sizeof(struct fio_overlapped));
	80	if (wd->ovls == NULL)
	81	rc = 1;
	82	}
	83
	84	if (!rc) {
	85	for (i = 0; i < td->o.iodepth; i++) {
	86	wd->ovls[i].io_free = TRUE;
	87	wd->ovls[i].io_complete = FALSE;
	88
	89	wd->ovls[i].o.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
	90	if (wd->ovls[i].o.hEvent == NULL) {
	91	rc = 1;
	92	break;
	93	}
	94	}
	95	}
	96
	97	if (!rc) {
	98	/* Create an auto-reset event */
	99	wd->iocomplete_event = CreateEvent(NULL, FALSE, FALSE, NULL);
	100	if (wd->iocomplete_event == NULL)
	101	rc = 1;
	102	}
	103
	104	if (rc) {
	105	if (wd != NULL) {
	106	if (wd->ovls != NULL)
	107	free(wd->ovls);
	108	if (wd->aio_events != NULL)
	109	free(wd->aio_events);
	110
	111	free(wd);
	112	}
	113	}
	114
	115	hKernel32Dll = GetModuleHandle("kernel32.dll");
	116	wd->pCancelIoEx = GetProcAddress(hKernel32Dll, "CancelIoEx");
	117
	118	td->io_ops->data = wd;
	119	return rc;
	120	}
	121
	122	static void fio_windowsaio_cleanup(struct thread_data *td)
	123	{
	124	int i;
	125	struct windowsaio_data *wd;
	126
	127	wd = td->io_ops->data;
	128
	129	if (wd != NULL) {
	130	wd->iothread_running = FALSE;
	131	WaitForSingleObject(wd->iothread, INFINITE);
	132
	133	CloseHandle(wd->iothread);
	134	CloseHandle(wd->iocomplete_event);
	135
	136	for (i = 0; i < td->o.iodepth; i++) {
	137	CloseHandle(wd->ovls[i].o.hEvent);
	138	}
	139
	140	free(wd->aio_events);
	141	free(wd->ovls);
	142	free(wd);
	143
	144	td->io_ops->data = NULL;
	145	}
	146	}
	147
	148
	149	static int fio_windowsaio_open_file(struct thread_data td, struct fio_file f)
	150	{
	151	int rc = 0;
	152	HANDLE hFile;
	153	DWORD flags = FILE_FLAG_POSIX_SEMANTICS \| FILE_FLAG_OVERLAPPED;
	154	DWORD sharemode = FILE_SHARE_READ \| FILE_SHARE_WRITE;
	155	DWORD openmode = OPEN_ALWAYS;
	156	DWORD access;
	157
	158	dprint(FD_FILE, "fd open %s\n", f->file_name);
	159
	160	if (f->filetype == FIO_TYPE_PIPE) {
	161	log_err("fio: windowsaio doesn't support pipes\n");
	162	return 1;
	163	}
	164
	165	if (!strcmp(f->file_name, "-")) {
	166	log_err("fio: can't read/write to stdin/out\n");
	167	return 1;
	168	}
	169
	170	if (td->o.odirect)
	171	flags \|= FILE_FLAG_NO_BUFFERING;
	172	if (td->o.sync_io)
	173	flags \|= FILE_FLAG_WRITE_THROUGH;
	174
	175	if (td->o.td_ddir == TD_DDIR_READ \|\|
	176	td->o.td_ddir == TD_DDIR_WRITE)
	177	flags \|= FILE_FLAG_SEQUENTIAL_SCAN;
	178	else
	179	flags \|= FILE_FLAG_RANDOM_ACCESS;
	180
	181	if (!td_write(td) \|\| read_only)
	182	access = GENERIC_READ;
	183	else
	184	access = (GENERIC_READ \| GENERIC_WRITE);
	185
	186	if (td->o.create_on_open > 0)
	187	openmode = OPEN_ALWAYS;
	188	else
	189	openmode = OPEN_EXISTING;
	190
	191	f->hFile = CreateFile(f->file_name, access, sharemode,
	192	NULL, openmode, flags, NULL);
	193
	194	if (f->hFile == INVALID_HANDLE_VALUE)
	195	rc = 1;
	196
	197	/* Only set up the competion port and thread if we're not just
	198	* querying the device size */
	199	if (!rc && td->io_ops->data != NULL) {
	200	struct thread_ctx *ctx;
	201	struct windowsaio_data *wd;
	202	hFile = CreateIoCompletionPort(f->hFile, NULL, 0, 0);
	203
	204	wd = td->io_ops->data;
	205
	206	wd->iothread_running = TRUE;
	207
	208	if (!rc) {
	209	ctx = malloc(sizeof(struct thread_ctx));
	210	ctx->iocp = hFile;
	211	ctx->wd = wd;
	212
	213	wd->iothread = CreateThread(NULL, 0, IoCompletionRoutine, ctx, 0, NULL);
	214	}
	215
	216	if (rc \|\| wd->iothread == NULL)
	217	rc = 1;
	218	}
	219
	220	return rc;
	221	}
	222
	223	static int fio_windowsaio_close_file(struct thread_data fio_unused td, struct fio_file f)
	224	{
	225	int rc = 0;
	226
	227	dprint(FD_FILE, "fd close %s\n", f->file_name);
	228
	229	if (f->hFile != INVALID_HANDLE_VALUE) {
	230	if (!CloseHandle(f->hFile))
	231	rc = 1;
	232	}
	233
	234	f->hFile = INVALID_HANDLE_VALUE;
	235	return rc;
	236	}
	237
	238	static BOOL timeout_expired(DWORD start_count, DWORD end_count)
	239	{
	240	BOOL expired = FALSE;
	241	DWORD current_time;
	242
	243	current_time = GetTickCount();
	244
	245	if ((end_count > start_count) && current_time >= end_count)
	246	expired = TRUE;
	247	else if (current_time < start_count && current_time > end_count)
	248	expired = TRUE;
	249
	250	return expired;
	251	}
	252
	253	static struct io_u* fio_windowsaio_event(struct thread_data *td, int event)
	254	{
	255	struct windowsaio_data *wd = td->io_ops->data;
	256	return wd->aio_events[event];
	257	}
	258
	259	static int fio_windowsaio_getevents(struct thread_data *td, unsigned int min,
	260	unsigned int max, struct timespec *t)
	261	{
	262	struct windowsaio_data *wd = td->io_ops->data;
	263	struct flist_head *entry;
	264	unsigned int dequeued = 0;
	265	struct io_u *io_u;
	266	struct fio_overlapped *fov;
	267	DWORD start_count = 0;
	268	DWORD end_count = 0;
	269	DWORD status;
	270	DWORD mswait = 250;
	271
	272	if (t != NULL) {
	273	mswait = (t->tv_sec * 1000) + (t->tv_nsec / 1000000);
	274	start_count = GetTickCount();
	275	end_count = start_count + (t->tv_sec * 1000) + (t->tv_nsec / 1000000);
	276	}
	277
	278	do {
	279	flist_for_each(entry, &td->io_u_busylist) {
	280	io_u = flist_entry(entry, struct io_u, list);
	281	fov = (struct fio_overlapped*)io_u->engine_data;
	282
	283	if (fov->io_complete) {
	284	fov->io_complete = FALSE;
	285	fov->io_free = TRUE;
	286	wd->aio_events[dequeued] = io_u;
	287	dequeued++;
	288	}
	289
	290	if (dequeued >= min)
	291	break;
	292	}
	293
	294	if (dequeued < min) {
	295	status = WaitForSingleObject(wd->iocomplete_event, mswait);
	296	if (status != WAIT_OBJECT_0 && dequeued > 0)
	297	break;
	298	}
	299
	300	if (dequeued >= min \|\| (t != NULL && timeout_expired(start_count, end_count)))
	301	break;
	302	} while (1);
	303
	304	return dequeued;
	305	}
	306
	307	static int fio_windowsaio_queue(struct thread_data *td,
	308	struct io_u *io_u)
	309	{
	310	LPOVERLAPPED lpOvl = NULL;
	311	struct windowsaio_data *wd;
	312	DWORD iobytes;
	313	BOOL success;
	314	int index;
	315	int rc = FIO_Q_COMPLETED;
	316
	317	fio_ro_check(td, io_u);
	318
	319	wd = td->io_ops->data;
	320
	321	for (index = 0; index < td->o.iodepth; index++) {
	322	if (wd->ovls[index].io_free) {
	323	wd->ovls[index].io_free = FALSE;
	324	ResetEvent(wd->ovls[index].o.hEvent);
	325	break;
	326	}
	327	}
	328
	329	assert(index < td->o.iodepth);
	330
	331	lpOvl = &wd->ovls[index].o;
	332	wd->ovls[index].io_u = io_u;
	333	lpOvl->Internal = STATUS_PENDING;
	334	lpOvl->InternalHigh = 0;
	335	lpOvl->Offset = io_u->offset & 0xFFFFFFFF;
	336	lpOvl->OffsetHigh = io_u->offset >> 32;
	337	lpOvl->Pointer = NULL;
	338	io_u->engine_data = &wd->ovls[index];
	339
	340	switch (io_u->ddir) {
	341	case DDIR_WRITE:
	342	success = WriteFile(io_u->file->hFile, io_u->xfer_buf, io_u->xfer_buflen, &iobytes, lpOvl);
	343	break;
	344	case DDIR_READ:
	345	success = ReadFile(io_u->file->hFile, io_u->xfer_buf, io_u->xfer_buflen, &iobytes, lpOvl);
	346	break;
	347	case DDIR_SYNC:
	348	case DDIR_DATASYNC:
	349	case DDIR_SYNC_FILE_RANGE:
	350	success = FlushFileBuffers(io_u->file->hFile);
	351	if (!success)
	352	io_u->error = GetLastError();
	353
	354	return FIO_Q_COMPLETED;
	355	break;
	356	case DDIR_TRIM:
	357	log_err("manual TRIM isn't supported on Windows");
	358	io_u->error = 1;
	359	io_u->resid = io_u->xfer_buflen;
	360	return FIO_Q_COMPLETED;
	361	break;
	362	default:
	363	assert(0);
	364	}
	365
	366	if (success \|\| GetLastError() == ERROR_IO_PENDING) {
	367	rc = FIO_Q_QUEUED;
	368	} else {
	369	io_u->error = GetLastError();
	370	io_u->resid = io_u->xfer_buflen;
	371	}
	372
	373	return rc;
	374	}
	375
	376	/* Runs as a thread and waits for queued IO to complete */
	377	static DWORD WINAPI IoCompletionRoutine(LPVOID lpParameter)
	378	{
	379	OVERLAPPED *ovl;
	380	struct fio_overlapped *fov;
	381	struct io_u *io_u;
	382	struct windowsaio_data *wd;
	383	struct thread_ctx *ctx;
	384	ULONG_PTR ulKey = 0;
	385	DWORD bytes;
	386
	387	ctx = (struct thread_ctx*)lpParameter;
	388	wd = ctx->wd;
	389
	390	do {
	391	if (!GetQueuedCompletionStatus(ctx->iocp, &bytes, &ulKey, &ovl, 250))
	392	continue;
	393
	394	fov = CONTAINING_RECORD(ovl, struct fio_overlapped, o);
	395	io_u = fov->io_u;
	396
	397	if (ovl->Internal == ERROR_SUCCESS) {
	398	io_u->resid = io_u->xfer_buflen - ovl->InternalHigh;
	399	io_u->error = 0;
	400	} else {
	401	io_u->resid = io_u->xfer_buflen;
	402	io_u->error = ovl->Internal;
	403	}
	404
	405	fov->io_complete = TRUE;
	406	SetEvent(wd->iocomplete_event);
	407	} while (ctx->wd->iothread_running);
	408
	409	CloseHandle(ctx->iocp);
	410	free(ctx);
	411	return 0;
	412	}
	413
	414	static int fio_windowsaio_cancel(struct thread_data *td,
	415	struct io_u *io_u)
	416	{
	417	int rc = 0;
	418
	419	struct windowsaio_data *wd = td->io_ops->data;
	420
	421	/* If we're running on Vista or newer, we can cancel individual IO requests */
	422	if (wd->pCancelIoEx != NULL) {
	423	struct fio_overlapped *ovl = io_u->engine_data;
	424	if (!wd->pCancelIoEx(io_u->file->hFile, &ovl->o))
	425	rc = 1;
	426	} else
	427	rc = 1;
	428
	429	return rc;
	430	}
	431
	432	static struct ioengine_ops ioengine = {
	433	.name = "windowsaio",
	434	.version = FIO_IOOPS_VERSION,
	435	.init = fio_windowsaio_init,
	436	.queue = fio_windowsaio_queue,
	437	.cancel = fio_windowsaio_cancel,
	438	.getevents = fio_windowsaio_getevents,
	439	.event = fio_windowsaio_event,
	440	.cleanup = fio_windowsaio_cleanup,
	441	.open_file = fio_windowsaio_open_file,
	442	.close_file = fio_windowsaio_close_file,
	443	.get_file_size = generic_get_file_size
	444	};
	445
	446	static void fio_init fio_posixaio_register(void)
	447	{
	448	register_ioengine(&ioengine);
	449	}
	450
	451	static void fio_exit fio_posixaio_unregister(void)
	452	{
	453	unregister_ioengine(&ioengine);
	454	}