[fio.git] / engines / sg.c

/*
 * scsi generic sg v3 io engine
 *
 */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <assert.h>
#include <sys/poll.h>

#include "../fio.h"
#include "../os.h"

#ifdef FIO_HAVE_SGIO

struct sgio_cmd {
	unsigned char cdb[10];
	int nr;
};

struct sgio_data {
	struct sgio_cmd *cmds;
	struct io_u **events;
	struct pollfd *pfds;
	int *fd_flags;
	void *sgbuf;
	unsigned int bs;
};

static void sgio_hdr_init(struct sgio_data *sd, struct sg_io_hdr *hdr,
			  struct io_u *io_u, int fs)
{
	struct sgio_cmd *sc = &sd->cmds[io_u->index];

	memset(hdr, 0, sizeof(*hdr));
	memset(sc->cdb, 0, sizeof(sc->cdb));

	hdr->interface_id = 'S';
	hdr->cmdp = sc->cdb;
	hdr->cmd_len = sizeof(sc->cdb);
	hdr->pack_id = io_u->index;
	hdr->usr_ptr = io_u;

	if (fs) {
		hdr->dxferp = io_u->xfer_buf;
		hdr->dxfer_len = io_u->xfer_buflen;
	}
}

static int pollin_events(struct pollfd *pfds, int fds)
{
	int i;

	for (i = 0; i < fds; i++)
		if (pfds[i].revents & POLLIN)
			return 1;

	return 0;
}

static int fio_sgio_getevents(struct thread_data *td, int min, int max,
			      struct timespec fio_unused *t)
{
	/*
	 * normally hard coding &td->files[0] is a bug that needs to be fixed,
	 * but it's ok here as all files should point to the same device.
	 */
	struct fio_file *f = &td->files[0];
	struct sgio_data *sd = td->io_ops->data;
	int left = max, ret, events, i, r = 0;
	void *buf = sd->sgbuf;

	/*
	 * Fill in the file descriptors
	 */
	for_each_file(td, f, i) {
		/*
		 * don't block for min events == 0
		 */
		if (!min) {
			sd->fd_flags[i] = fcntl(f->fd, F_GETFL);
			fcntl(f->fd, F_SETFL, sd->fd_flags[i] | O_NONBLOCK);
		}
		sd->pfds[i].fd = f->fd;
		sd->pfds[i].events = POLLIN;
	}

	while (left) {
		void *p;

		do {
			if (!min)
				break;

			ret = poll(sd->pfds, td->nr_files, -1);
			if (ret < 0) {
				if (!r)
					r = -errno;
				td_verror(td, errno, "poll");
				break;
			} else if (!ret)
				continue;

			if (pollin_events(sd->pfds, td->nr_files))
				break;
		} while (1);

		if (r < 0)
			break;

re_read:
		p = buf;
		events = 0;
		for_each_file(td, f, i) {
			ret = read(f->fd, p, left * sizeof(struct sg_io_hdr));
			if (ret < 0) {
				if (errno == EAGAIN)
					continue;
				r = -errno;
				td_verror(td, errno, "read");
				break;
			} else if (ret) {
				p += ret;
				events += ret / sizeof(struct sg_io_hdr);
			}
		}

		if (r < 0)
			break;
		if (!events) {
			usleep(1000);
			goto re_read;
		}

		left -= events;
		r += events;

		for (i = 0; i < events; i++) {
			struct sg_io_hdr *hdr = (struct sg_io_hdr *) buf + i;

			sd->events[i] = hdr->usr_ptr;
		}
	}

	if (!min) {
		for_each_file(td, f, i)
			fcntl(f->fd, F_SETFL, sd->fd_flags[i]);
	}

	return r;
}

static int fio_sgio_ioctl_doio(struct thread_data *td,
			       struct fio_file *f, struct io_u *io_u)
{
	struct sgio_data *sd = td->io_ops->data;
	struct sg_io_hdr *hdr = &io_u->hdr;
	int ret;

	sd->events[0] = io_u;

	ret = ioctl(f->fd, SG_IO, hdr);
	if (ret < 0)
		return -errno;

	return FIO_Q_COMPLETED;
}

static int fio_sgio_rw_doio(struct fio_file *f, struct io_u *io_u, int sync)
{
	struct sg_io_hdr *hdr = &io_u->hdr;
	int ret;

	ret = write(f->fd, hdr, sizeof(*hdr));
	if (ret < 0)
		return errno;

	if (sync) {
		ret = read(f->fd, hdr, sizeof(*hdr));
		if (ret < 0)
			return -errno;
		return FIO_Q_COMPLETED;
	}

	return FIO_Q_QUEUED;
}

static int fio_sgio_doio(struct thread_data *td, struct io_u *io_u, int sync)
{
	struct fio_file *f = io_u->file;

	if (td->filetype == FIO_TYPE_BD)
		return fio_sgio_ioctl_doio(td, f, io_u);

	return fio_sgio_rw_doio(f, io_u, sync);
}

static int fio_sgio_prep(struct thread_data *td, struct io_u *io_u)
{
	struct sg_io_hdr *hdr = &io_u->hdr;
	struct sgio_data *sd = td->io_ops->data;
	int nr_blocks, lba;

	if (io_u->xfer_buflen & (sd->bs - 1)) {
		log_err("read/write not sector aligned\n");
		return EINVAL;
	}

	if (io_u->ddir == DDIR_READ) {
		sgio_hdr_init(sd, hdr, io_u, 1);

		hdr->dxfer_direction = SG_DXFER_FROM_DEV;
		hdr->cmdp[0] = 0x28;
	} else if (io_u->ddir == DDIR_WRITE) {
		sgio_hdr_init(sd, hdr, io_u, 1);

		hdr->dxfer_direction = SG_DXFER_TO_DEV;
		hdr->cmdp[0] = 0x2a;
	} else {
		sgio_hdr_init(sd, hdr, io_u, 0);

		hdr->dxfer_direction = SG_DXFER_NONE;
		hdr->cmdp[0] = 0x35;
	}

	if (hdr->dxfer_direction != SG_DXFER_NONE) {
		nr_blocks = io_u->xfer_buflen / sd->bs;
		lba = io_u->offset / sd->bs;
		hdr->cmdp[2] = (unsigned char) ((lba >> 24) & 0xff);
		hdr->cmdp[3] = (unsigned char) ((lba >> 16) & 0xff);
		hdr->cmdp[4] = (unsigned char) ((lba >>  8) & 0xff);
		hdr->cmdp[5] = (unsigned char) (lba & 0xff);
		hdr->cmdp[7] = (unsigned char) ((nr_blocks >> 8) & 0xff);
		hdr->cmdp[8] = (unsigned char) (nr_blocks & 0xff);
	}

	return 0;
}

static int fio_sgio_queue(struct thread_data *td, struct io_u *io_u)
{
	struct sg_io_hdr *hdr = &io_u->hdr;
	int ret;

	ret = fio_sgio_doio(td, io_u, io_u->ddir == DDIR_SYNC);

	if (ret < 0)
		io_u->error = errno;
	else if (hdr->status) {
		io_u->resid = hdr->resid;
		io_u->error = EIO;
	}

	if (io_u->error) {
		td_verror(td, io_u->error, "xfer");
		return FIO_Q_COMPLETED;
	}

	return ret;
}

static struct io_u *fio_sgio_event(struct thread_data *td, int event)
{
	struct sgio_data *sd = td->io_ops->data;

	return sd->events[event];
}

static int fio_sgio_get_bs(struct thread_data *td, unsigned int *bs)
{
	struct sgio_data *sd = td->io_ops->data;
	struct io_u *io_u;
	struct sg_io_hdr *hdr;
	unsigned char buf[8];
	int ret;

	io_u = __get_io_u(td);
	io_u->file = &td->files[0];
	assert(io_u);

	hdr = &io_u->hdr;
	sgio_hdr_init(sd, hdr, io_u, 0);
	memset(buf, 0, sizeof(buf));

	hdr->cmdp[0] = 0x25;
	hdr->dxfer_direction = SG_DXFER_FROM_DEV;
	hdr->dxferp = buf;
	hdr->dxfer_len = sizeof(buf);

	ret = fio_sgio_doio(td, io_u, 1);
	if (ret) {
		put_io_u(td, io_u);
		return ret;
	}

	*bs = (buf[4] << 24) | (buf[5] << 16) | (buf[6] << 8) | buf[7];
	put_io_u(td, io_u);
	return 0;
}

static void fio_sgio_cleanup(struct thread_data *td)
{
	struct sgio_data *sd = td->io_ops->data;

	if (sd) {
		free(sd->events);
		free(sd->cmds);
		free(sd->fd_flags);
		free(sd->pfds);
		free(sd->sgbuf);
		free(sd);

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

static int fio_sgio_init(struct thread_data *td)
{
	struct fio_file *f = &td->files[0];
	struct sgio_data *sd;
	unsigned int bs;
	int ret;

	sd = malloc(sizeof(*sd));
	memset(sd, 0, sizeof(*sd));
	sd->cmds = malloc(td->iodepth * sizeof(struct sgio_cmd));
	memset(sd->cmds, 0, td->iodepth * sizeof(struct sgio_cmd));
	sd->events = malloc(td->iodepth * sizeof(struct io_u *));
	memset(sd->events, 0, td->iodepth * sizeof(struct io_u *));
	sd->pfds = malloc(sizeof(struct pollfd) * td->nr_files);
	memset(sd->pfds, 0, sizeof(struct pollfd) * td->nr_files);
	sd->fd_flags = malloc(sizeof(int) * td->nr_files);
	memset(sd->fd_flags, 0, sizeof(int) * td->nr_files);
	sd->sgbuf = malloc(sizeof(struct sg_io_hdr) * td->iodepth);
	memset(sd->sgbuf, 0, sizeof(struct sg_io_hdr) * td->iodepth);

	td->io_ops->data = sd;

	if (td->filetype == FIO_TYPE_BD) {
		if (ioctl(f->fd, BLKSSZGET, &bs) < 0) {
			td_verror(td, errno, "ioctl");
			goto err;
		}
	} else if (td->filetype == FIO_TYPE_CHAR) {
		int version;

		if (ioctl(f->fd, SG_GET_VERSION_NUM, &version) < 0) {
			td_verror(td, errno, "ioctl");
			goto err;
		}

		ret = fio_sgio_get_bs(td, &bs);
		if (ret)
			goto err;
	} else {
		log_err("ioengine sgio only works on block devices\n");
		goto err;
	}

	sd->bs = bs;

	if (td->filetype == FIO_TYPE_BD) {
		td->io_ops->getevents = NULL;
		td->io_ops->event = NULL;
	}

	/*
	 * we want to do it, regardless of whether odirect is set or not
	 */
	td->override_sync = 1;
	return 0;
err:
	free(sd->events);
	free(sd->cmds);
	free(sd->fd_flags);
	free(sd->pfds);
	free(sd->sgbuf);
	free(sd);
	td->io_ops->data = NULL;
	return 1;
}

static struct ioengine_ops ioengine = {
	.name		= "sg",
	.version	= FIO_IOOPS_VERSION,
	.init		= fio_sgio_init,
	.prep		= fio_sgio_prep,
	.queue		= fio_sgio_queue,
	.getevents	= fio_sgio_getevents,
	.event		= fio_sgio_event,
	.cleanup	= fio_sgio_cleanup,
	.flags		= FIO_SYNCIO | FIO_RAWIO,
};

#else /* FIO_HAVE_SGIO */

/*
 * When we have a proper configure system in place, we simply wont build
 * and install this io engine. For now install a crippled version that
 * just complains and fails to load.
 */
static int fio_sgio_init(struct thread_data fio_unused *td)
{
	fprintf(stderr, "fio: sgio not available\n");
	return 1;
}

static struct ioengine_ops ioengine = {
	.name		= "sgio",
	.version	= FIO_IOOPS_VERSION,
	.init		= fio_sgio_init,
};

#endif

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

static void fio_exit fio_sgio_unregister(void)
{
	unregister_ioengine(&ioengine);
}
Commit	Line	Data
	1	/*
	2	* scsi generic sg v3 io engine
	3	*
	4	*/
	5	#include <stdio.h>
	6	#include <stdlib.h>
	7	#include <unistd.h>
	8	#include <errno.h>
	9	#include <assert.h>
	10	#include <sys/poll.h>
	11
	12	#include "../fio.h"
	13	#include "../os.h"
	14
	15	#ifdef FIO_HAVE_SGIO
	16
	17	struct sgio_cmd {
	18	unsigned char cdb[10];
	19	int nr;
	20	};
	21
	22	struct sgio_data {
	23	struct sgio_cmd *cmds;
	24	struct io_u **events;
	25	struct pollfd *pfds;
	26	int *fd_flags;
	27	void *sgbuf;
	28	unsigned int bs;
	29	};
	30
	31	static void sgio_hdr_init(struct sgio_data sd, struct sg_io_hdr hdr,
	32	struct io_u *io_u, int fs)
	33	{
	34	struct sgio_cmd *sc = &sd->cmds[io_u->index];
	35
	36	memset(hdr, 0, sizeof(*hdr));
	37	memset(sc->cdb, 0, sizeof(sc->cdb));
	38
	39	hdr->interface_id = 'S';
	40	hdr->cmdp = sc->cdb;
	41	hdr->cmd_len = sizeof(sc->cdb);
	42	hdr->pack_id = io_u->index;
	43	hdr->usr_ptr = io_u;
	44
	45	if (fs) {
	46	hdr->dxferp = io_u->xfer_buf;
	47	hdr->dxfer_len = io_u->xfer_buflen;
	48	}
	49	}
	50
	51	static int pollin_events(struct pollfd *pfds, int fds)
	52	{
	53	int i;
	54
	55	for (i = 0; i < fds; i++)
	56	if (pfds[i].revents & POLLIN)
	57	return 1;
	58
	59	return 0;
	60	}
	61
	62	static int fio_sgio_getevents(struct thread_data *td, int min, int max,
	63	struct timespec fio_unused *t)
	64	{
	65	/*
	66	* normally hard coding &td->files[0] is a bug that needs to be fixed,
	67	* but it's ok here as all files should point to the same device.
	68	*/
	69	struct fio_file *f = &td->files[0];
	70	struct sgio_data *sd = td->io_ops->data;
	71	int left = max, ret, events, i, r = 0;
	72	void *buf = sd->sgbuf;
	73
	74	/*
	75	* Fill in the file descriptors
	76	*/
	77	for_each_file(td, f, i) {
	78	/*
	79	* don't block for min events == 0
	80	*/
	81	if (!min) {
	82	sd->fd_flags[i] = fcntl(f->fd, F_GETFL);
	83	fcntl(f->fd, F_SETFL, sd->fd_flags[i] \| O_NONBLOCK);
	84	}
	85	sd->pfds[i].fd = f->fd;
	86	sd->pfds[i].events = POLLIN;
	87	}
	88
	89	while (left) {
	90	void *p;
	91
	92	do {
	93	if (!min)
	94	break;
	95
	96	ret = poll(sd->pfds, td->nr_files, -1);
	97	if (ret < 0) {
	98	if (!r)
	99	r = -errno;
	100	td_verror(td, errno, "poll");
	101	break;
	102	} else if (!ret)
	103	continue;
	104
	105	if (pollin_events(sd->pfds, td->nr_files))
	106	break;
	107	} while (1);
	108
	109	if (r < 0)
	110	break;
	111
	112	re_read:
	113	p = buf;
	114	events = 0;
	115	for_each_file(td, f, i) {
	116	ret = read(f->fd, p, left * sizeof(struct sg_io_hdr));
	117	if (ret < 0) {
	118	if (errno == EAGAIN)
	119	continue;
	120	r = -errno;
	121	td_verror(td, errno, "read");
	122	break;
	123	} else if (ret) {
	124	p += ret;
	125	events += ret / sizeof(struct sg_io_hdr);
	126	}
	127	}
	128
	129	if (r < 0)
	130	break;
	131	if (!events) {
	132	usleep(1000);
	133	goto re_read;
	134	}
	135
	136	left -= events;
	137	r += events;
	138
	139	for (i = 0; i < events; i++) {
	140	struct sg_io_hdr hdr = (struct sg_io_hdr ) buf + i;
	141
	142	sd->events[i] = hdr->usr_ptr;
	143	}
	144	}
	145
	146	if (!min) {
	147	for_each_file(td, f, i)
	148	fcntl(f->fd, F_SETFL, sd->fd_flags[i]);
	149	}
	150
	151	return r;
	152	}
	153
	154	static int fio_sgio_ioctl_doio(struct thread_data *td,
	155	struct fio_file f, struct io_u io_u)
	156	{
	157	struct sgio_data *sd = td->io_ops->data;
	158	struct sg_io_hdr *hdr = &io_u->hdr;
	159	int ret;
	160
	161	sd->events[0] = io_u;
	162
	163	ret = ioctl(f->fd, SG_IO, hdr);
	164	if (ret < 0)
	165	return -errno;
	166
	167	return FIO_Q_COMPLETED;
	168	}
	169
	170	static int fio_sgio_rw_doio(struct fio_file f, struct io_u io_u, int sync)
	171	{
	172	struct sg_io_hdr *hdr = &io_u->hdr;
	173	int ret;
	174
	175	ret = write(f->fd, hdr, sizeof(*hdr));
	176	if (ret < 0)
	177	return errno;
	178
	179	if (sync) {
	180	ret = read(f->fd, hdr, sizeof(*hdr));
	181	if (ret < 0)
	182	return -errno;
	183	return FIO_Q_COMPLETED;
	184	}
	185
	186	return FIO_Q_QUEUED;
	187	}
	188
	189	static int fio_sgio_doio(struct thread_data td, struct io_u io_u, int sync)
	190	{
	191	struct fio_file *f = io_u->file;
	192
	193	if (td->filetype == FIO_TYPE_BD)
	194	return fio_sgio_ioctl_doio(td, f, io_u);
	195
	196	return fio_sgio_rw_doio(f, io_u, sync);
	197	}
	198
	199	static int fio_sgio_prep(struct thread_data td, struct io_u io_u)
	200	{
	201	struct sg_io_hdr *hdr = &io_u->hdr;
	202	struct sgio_data *sd = td->io_ops->data;
	203	int nr_blocks, lba;
	204
	205	if (io_u->xfer_buflen & (sd->bs - 1)) {
	206	log_err("read/write not sector aligned\n");
	207	return EINVAL;
	208	}
	209
	210	if (io_u->ddir == DDIR_READ) {
	211	sgio_hdr_init(sd, hdr, io_u, 1);
	212
	213	hdr->dxfer_direction = SG_DXFER_FROM_DEV;
	214	hdr->cmdp[0] = 0x28;
	215	} else if (io_u->ddir == DDIR_WRITE) {
	216	sgio_hdr_init(sd, hdr, io_u, 1);
	217
	218	hdr->dxfer_direction = SG_DXFER_TO_DEV;
	219	hdr->cmdp[0] = 0x2a;
	220	} else {
	221	sgio_hdr_init(sd, hdr, io_u, 0);
	222
	223	hdr->dxfer_direction = SG_DXFER_NONE;
	224	hdr->cmdp[0] = 0x35;
	225	}
	226
	227	if (hdr->dxfer_direction != SG_DXFER_NONE) {
	228	nr_blocks = io_u->xfer_buflen / sd->bs;
	229	lba = io_u->offset / sd->bs;
	230	hdr->cmdp[2] = (unsigned char) ((lba >> 24) & 0xff);
	231	hdr->cmdp[3] = (unsigned char) ((lba >> 16) & 0xff);
	232	hdr->cmdp[4] = (unsigned char) ((lba >> 8) & 0xff);
	233	hdr->cmdp[5] = (unsigned char) (lba & 0xff);
	234	hdr->cmdp[7] = (unsigned char) ((nr_blocks >> 8) & 0xff);
	235	hdr->cmdp[8] = (unsigned char) (nr_blocks & 0xff);
	236	}
	237
	238	return 0;
	239	}
	240
	241	static int fio_sgio_queue(struct thread_data td, struct io_u io_u)
	242	{
	243	struct sg_io_hdr *hdr = &io_u->hdr;
	244	int ret;
	245
	246	ret = fio_sgio_doio(td, io_u, io_u->ddir == DDIR_SYNC);
	247
	248	if (ret < 0)
	249	io_u->error = errno;
	250	else if (hdr->status) {
	251	io_u->resid = hdr->resid;
	252	io_u->error = EIO;
	253	}
	254
	255	if (io_u->error) {
	256	td_verror(td, io_u->error, "xfer");
	257	return FIO_Q_COMPLETED;
	258	}
	259
	260	return ret;
	261	}
	262
	263	static struct io_u fio_sgio_event(struct thread_data td, int event)
	264	{
	265	struct sgio_data *sd = td->io_ops->data;
	266
	267	return sd->events[event];
	268	}
	269
	270	static int fio_sgio_get_bs(struct thread_data td, unsigned int bs)
	271	{
	272	struct sgio_data *sd = td->io_ops->data;
	273	struct io_u *io_u;
	274	struct sg_io_hdr *hdr;
	275	unsigned char buf[8];
	276	int ret;
	277
	278	io_u = __get_io_u(td);
	279	io_u->file = &td->files[0];
	280	assert(io_u);
	281
	282	hdr = &io_u->hdr;
	283	sgio_hdr_init(sd, hdr, io_u, 0);
	284	memset(buf, 0, sizeof(buf));
	285
	286	hdr->cmdp[0] = 0x25;
	287	hdr->dxfer_direction = SG_DXFER_FROM_DEV;
	288	hdr->dxferp = buf;
	289	hdr->dxfer_len = sizeof(buf);
	290
	291	ret = fio_sgio_doio(td, io_u, 1);
	292	if (ret) {
	293	put_io_u(td, io_u);
	294	return ret;
	295	}
	296
	297	*bs = (buf[4] << 24) \| (buf[5] << 16) \| (buf[6] << 8) \| buf[7];
	298	put_io_u(td, io_u);
	299	return 0;
	300	}
	301
	302	static void fio_sgio_cleanup(struct thread_data *td)
	303	{
	304	struct sgio_data *sd = td->io_ops->data;
	305
	306	if (sd) {
	307	free(sd->events);
	308	free(sd->cmds);
	309	free(sd->fd_flags);
	310	free(sd->pfds);
	311	free(sd->sgbuf);
	312	free(sd);
	313
	314	td->io_ops->data = NULL;
	315	}
	316	}
	317
	318	static int fio_sgio_init(struct thread_data *td)
	319	{
	320	struct fio_file *f = &td->files[0];
	321	struct sgio_data *sd;
	322	unsigned int bs;
	323	int ret;
	324
	325	sd = malloc(sizeof(*sd));
	326	memset(sd, 0, sizeof(*sd));
	327	sd->cmds = malloc(td->iodepth * sizeof(struct sgio_cmd));
	328	memset(sd->cmds, 0, td->iodepth * sizeof(struct sgio_cmd));
	329	sd->events = malloc(td->iodepth * sizeof(struct io_u *));
	330	memset(sd->events, 0, td->iodepth * sizeof(struct io_u *));
	331	sd->pfds = malloc(sizeof(struct pollfd) * td->nr_files);
	332	memset(sd->pfds, 0, sizeof(struct pollfd) * td->nr_files);
	333	sd->fd_flags = malloc(sizeof(int) * td->nr_files);
	334	memset(sd->fd_flags, 0, sizeof(int) * td->nr_files);
	335	sd->sgbuf = malloc(sizeof(struct sg_io_hdr) * td->iodepth);
	336	memset(sd->sgbuf, 0, sizeof(struct sg_io_hdr) * td->iodepth);
	337
	338	td->io_ops->data = sd;
	339
	340	if (td->filetype == FIO_TYPE_BD) {
	341	if (ioctl(f->fd, BLKSSZGET, &bs) < 0) {
	342	td_verror(td, errno, "ioctl");
	343	goto err;
	344	}
	345	} else if (td->filetype == FIO_TYPE_CHAR) {
	346	int version;
	347
	348	if (ioctl(f->fd, SG_GET_VERSION_NUM, &version) < 0) {
	349	td_verror(td, errno, "ioctl");
	350	goto err;
	351	}
	352
	353	ret = fio_sgio_get_bs(td, &bs);
	354	if (ret)
	355	goto err;
	356	} else {
	357	log_err("ioengine sgio only works on block devices\n");
	358	goto err;
	359	}
	360
	361	sd->bs = bs;
	362
	363	if (td->filetype == FIO_TYPE_BD) {
	364	td->io_ops->getevents = NULL;
	365	td->io_ops->event = NULL;
	366	}
	367
	368	/*
	369	* we want to do it, regardless of whether odirect is set or not
	370	*/
	371	td->override_sync = 1;
	372	return 0;
	373	err:
	374	free(sd->events);
	375	free(sd->cmds);
	376	free(sd->fd_flags);
	377	free(sd->pfds);
	378	free(sd->sgbuf);
	379	free(sd);
	380	td->io_ops->data = NULL;
	381	return 1;
	382	}
	383
	384	static struct ioengine_ops ioengine = {
	385	.name = "sg",
	386	.version = FIO_IOOPS_VERSION,
	387	.init = fio_sgio_init,
	388	.prep = fio_sgio_prep,
	389	.queue = fio_sgio_queue,
	390	.getevents = fio_sgio_getevents,
	391	.event = fio_sgio_event,
	392	.cleanup = fio_sgio_cleanup,
	393	.flags = FIO_SYNCIO \| FIO_RAWIO,
	394	};
	395
	396	#else /* FIO_HAVE_SGIO */
	397
	398	/*
	399	* When we have a proper configure system in place, we simply wont build
	400	* and install this io engine. For now install a crippled version that
	401	* just complains and fails to load.
	402	*/
	403	static int fio_sgio_init(struct thread_data fio_unused *td)
	404	{
	405	fprintf(stderr, "fio: sgio not available\n");
	406	return 1;
	407	}
	408
	409	static struct ioengine_ops ioengine = {
	410	.name = "sgio",
	411	.version = FIO_IOOPS_VERSION,
	412	.init = fio_sgio_init,
	413	};
	414
	415	#endif
	416
	417	static void fio_init fio_sgio_register(void)
	418	{
	419	register_ioengine(&ioengine);
	420	}
	421
	422	static void fio_exit fio_sgio_unregister(void)
	423	{
	424	unregister_ioengine(&ioengine);
	425	}