X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=engines%2Fsg.c;h=360775fb831c32a0b0739a97c7677672f31fe973;hp=6c997bd47cad75523582ea77bc7da454396c69f0;hb=f39159a3e578a88459c80d9efd12529399c12550;hpb=6ab9e267d0a48de95c86875ba93fe17203163bb0

diff --git a/engines/sg.c b/engines/sg.c
index 6c997bd4..360775fb 100644
--- a/engines/sg.c
+++ b/engines/sg.c
@@ -1,5 +1,7 @@
 /*
- * scsi generic sg v3 io engine
+ * sg engine
+ *
+ * IO engine that uses the Linux SG v3 interface to talk to SCSI devices
  *
  */
 #include <stdio.h>
@@ -10,19 +12,28 @@
 #include <sys/poll.h>
 
 #include "../fio.h"
-#include "../os.h"
 
 #ifdef FIO_HAVE_SGIO
 
+#define MAX_10B_LBA  0xFFFFFFFFULL
+#define SCSI_TIMEOUT_MS 30000   // 30 second timeout; currently no method to override
+#define MAX_SB 64               // sense block maximum return size
+
 struct sgio_cmd {
-	unsigned char cdb[10];
+	unsigned char cdb[16];  	// increase to support 16 byte commands
+	unsigned char sb[MAX_SB];   // add sense block to commands
 	int nr;
 };
 
 struct sgio_data {
 	struct sgio_cmd *cmds;
 	struct io_u **events;
+	struct pollfd *pfds;
+	int *fd_flags;
+	void *sgbuf;
 	unsigned int bs;
+	long long max_lba;
+	int type_checked;
 };
 
 static void sgio_hdr_init(struct sgio_data *sd, struct sg_io_hdr *hdr,
@@ -36,6 +47,8 @@ static void sgio_hdr_init(struct sgio_data *sd, struct sg_io_hdr *hdr,
 	hdr->interface_id = 'S';
 	hdr->cmdp = sc->cdb;
 	hdr->cmd_len = sizeof(sc->cdb);
+	hdr->sbp = sc->sb;
+	hdr->mx_sb_len = sizeof(sc->sb);
 	hdr->pack_id = io_u->index;
 	hdr->usr_ptr = io_u;
 
@@ -45,21 +58,6 @@ static void sgio_hdr_init(struct sgio_data *sd, struct sg_io_hdr *hdr,
 	}
 }
 
-static int fio_sgio_ioctl_getevents(struct thread_data *td, int fio_unused min,
-				    int max, struct timespec fio_unused *t)
-{
-	assert(max <= 1);
-
-	/*
-	 * we can only have one finished io_u for sync io, since the depth
-	 * is always 1
-	 */
-	if (list_empty(&td->io_u_busylist))
-		return 0;
-
-	return 1;
-}
-
 static int pollin_events(struct pollfd *pfds, int fds)
 {
 	int i;
@@ -71,55 +69,80 @@ static int pollin_events(struct pollfd *pfds, int fds)
 	return 0;
 }
 
-static int fio_sgio_getevents(struct thread_data *td, int min, int max,
-			      struct timespec fio_unused *t)
+static int sg_fd_read(int fd, void *data, size_t size)
+{
+	int err = 0;
+
+	while (size) {
+		ssize_t ret;
+
+		ret = read(fd, data, size);
+		if (ret < 0) {
+			if (errno == EAGAIN || errno == EINTR)
+				continue;
+			err = errno;
+			break;
+		} else if (!ret)
+			break;
+		else {
+			data += ret;
+			size -= ret;
+		}
+	}
+
+	if (err)
+		return err;
+	if (size)
+		return EAGAIN;
+
+	return 0;
+}
+
+static int fio_sgio_getevents(struct thread_data *td, unsigned int min,
+			      unsigned int max,
+			      const 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, *fl;
-	struct pollfd *pfds;
-	void *buf;
+	int left = max, eventNum, ret, r = 0;
+	void *buf = sd->sgbuf;
+	unsigned int i, events;
+	struct fio_file *f;
 
 	/*
 	 * Fill in the file descriptors
 	 */
-	pfds = malloc(sizeof(struct pollfd) * td->nr_files);
-	fl = malloc(sizeof(int) * td->nr_files);
-
 	for_each_file(td, f, i) {
 		/*
 		 * don't block for min events == 0
 		 */
-		if (!min) {
-			fl[i] = fcntl(f->fd, F_GETFL);
-			fcntl(f->fd, F_SETFL, fl[i] | O_NONBLOCK);
-		}
-		pfds[i].fd = f->fd;
-		pfds[i].events = POLLIN;
+		if (!min)
+			sd->fd_flags[i] = fio_set_fd_nonblocking(f->fd, "sg");
+		else
+			sd->fd_flags[i] = -1;
+
+		sd->pfds[i].fd = f->fd;
+		sd->pfds[i].events = POLLIN;
 	}
 
-	buf = malloc(max * sizeof(struct sg_io_hdr));
 	while (left) {
 		void *p;
 
+		dprint(FD_IO, "sgio_getevents: sd %p: left=%d\n", sd, left);
+
 		do {
 			if (!min)
 				break;
 
-			ret = poll(pfds, td->nr_files, -1);
+			ret = poll(sd->pfds, td->o.nr_files, -1);
 			if (ret < 0) {
-				td_verror(td, errno);
 				if (!r)
-					r = -1;
+					r = -errno;
+				td_verror(td, errno, "poll");
 				break;
 			} else if (!ret)
 				continue;
 
-			if (pollin_events(pfds, td->nr_files))
+			if (pollin_events(sd->pfds, td->o.nr_files))
 				break;
 		} while (1);
 
@@ -130,20 +153,21 @@ 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;
-				td_verror(td, errno);
-				r = -1;
-				break;
-			} else if (ret) {
-				p += ret;
-				events += ret / sizeof(struct sg_io_hdr);
+			for (eventNum = 0; eventNum < left; eventNum++) {
+				ret = sg_fd_read(f->fd, p, sizeof(struct sg_io_hdr));
+				dprint(FD_IO, "sgio_getevents: ret: %d\n", ret);
+				if (ret) {
+					r = -ret;
+					td_verror(td, r, "sg_read");
+					break;
+				}
+				p += sizeof(struct sg_io_hdr);
+				events++;
+				dprint(FD_IO, "sgio_getevents: events: %d\n", events);
 			}
 		}
 
-		if (r < 0)
+		if (r < 0 && !events)
 			break;
 		if (!events) {
 			usleep(1000);
@@ -155,19 +179,28 @@ re_read:
 
 		for (i = 0; i < events; i++) {
 			struct sg_io_hdr *hdr = (struct sg_io_hdr *) buf + i;
-
 			sd->events[i] = hdr->usr_ptr;
+
+			/* record if an io error occurred, ignore resid */
+			if (hdr->info & SG_INFO_CHECK) {
+				struct io_u *io_u;
+				io_u = (struct io_u *)(hdr->usr_ptr);
+				memcpy((void*)&(io_u->hdr), (void*)hdr, sizeof(struct sg_io_hdr));
+				sd->events[i]->error = EIO;
+			}
 		}
 	}
 
 	if (!min) {
-		for_each_file(td, f, i)
-			fcntl(f->fd, F_SETFL, fl[i]);
+		for_each_file(td, f, i) {
+			if (sd->fd_flags[i] == -1)
+				continue;
+
+			if (fcntl(f->fd, F_SETFL, sd->fd_flags[i]) < 0)
+				log_err("fio: sg failed to restore fcntl flags: %s\n", strerror(errno));
+		}
 	}
 
-	free(buf);
-	free(pfds);
-	free(fl);
 	return r;
 }
 
@@ -176,88 +209,145 @@ static int fio_sgio_ioctl_doio(struct thread_data *td,
 {
 	struct sgio_data *sd = td->io_ops->data;
 	struct sg_io_hdr *hdr = &io_u->hdr;
+	int ret;
 
 	sd->events[0] = io_u;
 
-	return ioctl(f->fd, SG_IO, hdr);
+	ret = ioctl(f->fd, SG_IO, hdr);
+	if (ret < 0)
+		return ret;
+
+	/* record if an io error occurred */
+	if (hdr->info & SG_INFO_CHECK)
+		io_u->error = EIO;
+
+	return FIO_Q_COMPLETED;
 }
 
-static int fio_sgio_rw_doio(struct fio_file *f, struct io_u *io_u, int sync)
+static int fio_sgio_rw_doio(struct fio_file *f, struct io_u *io_u, int do_sync)
 {
 	struct sg_io_hdr *hdr = &io_u->hdr;
 	int ret;
 
 	ret = write(f->fd, hdr, sizeof(*hdr));
 	if (ret < 0)
-		return errno;
+		return ret;
 
-	if (sync) {
+	if (do_sync) {
 		ret = read(f->fd, hdr, sizeof(*hdr));
 		if (ret < 0)
-			return errno;
+			return ret;
+
+		/* record if an io error occurred */
+		if (hdr->info & SG_INFO_CHECK)
+			io_u->error = EIO;
+
+		return FIO_Q_COMPLETED;
 	}
 
-	return 0;
+	return FIO_Q_QUEUED;
 }
 
-static int fio_sgio_doio(struct thread_data *td, struct io_u *io_u, int sync)
+static int fio_sgio_doio(struct thread_data *td, struct io_u *io_u, int do_sync)
 {
 	struct fio_file *f = io_u->file;
+	int ret;
 
-	if (td->filetype == FIO_TYPE_BD)
-		return fio_sgio_ioctl_doio(td, f, io_u);
+	if (f->filetype == FIO_TYPE_BD) {
+		ret = fio_sgio_ioctl_doio(td, f, io_u);
+		td->error = io_u->error;
+	} else {
+		ret = fio_sgio_rw_doio(f, io_u, do_sync);
+		if (do_sync)
+			td->error = io_u->error;
+	}
 
-	return fio_sgio_rw_doio(f, io_u, sync);
+	return ret;
 }
 
 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;
+	long long nr_blocks, lba;
 
 	if (io_u->xfer_buflen & (sd->bs - 1)) {
 		log_err("read/write not sector aligned\n");
 		return EINVAL;
 	}
 
+	nr_blocks = io_u->xfer_buflen / sd->bs;
+	lba = io_u->offset / sd->bs;
+
 	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;
+		if (lba < MAX_10B_LBA)
+			hdr->cmdp[0] = 0x28; // read(10)
+		else
+			hdr->cmdp[0] = 0x88; // read(16)
 	} 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;
+		if (lba < MAX_10B_LBA)
+			hdr->cmdp[0] = 0x2a; // write(10)
+		else
+			hdr->cmdp[0] = 0x8a; // write(16)
 	} else {
 		sgio_hdr_init(sd, hdr, io_u, 0);
-
 		hdr->dxfer_direction = SG_DXFER_NONE;
-		hdr->cmdp[0] = 0x35;
+		if (lba < MAX_10B_LBA)
+			hdr->cmdp[0] = 0x35; // synccache(10)
+		else
+			hdr->cmdp[0] = 0x91; // synccache(16)
 	}
 
+	/*
+	 * for synccache, we leave lba and length to 0 to sync all
+	 * blocks on medium.
+	 */
 	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);
+
+		if (lba < MAX_10B_LBA) {
+			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);
+		} else {
+			hdr->cmdp[2] = (unsigned char) ((lba >> 56) & 0xff);
+			hdr->cmdp[3] = (unsigned char) ((lba >> 48) & 0xff);
+			hdr->cmdp[4] = (unsigned char) ((lba >> 40) & 0xff);
+			hdr->cmdp[5] = (unsigned char) ((lba >> 32) & 0xff);
+			hdr->cmdp[6] = (unsigned char) ((lba >> 24) & 0xff);
+			hdr->cmdp[7] = (unsigned char) ((lba >> 16) & 0xff);
+			hdr->cmdp[8] = (unsigned char) ((lba >>  8) & 0xff);
+			hdr->cmdp[9] = (unsigned char) (lba & 0xff);
+			hdr->cmdp[10] = (unsigned char) ((nr_blocks >> 32) & 0xff);
+			hdr->cmdp[11] = (unsigned char) ((nr_blocks >> 16) & 0xff);
+			hdr->cmdp[12] = (unsigned char) ((nr_blocks >> 8) & 0xff);
+			hdr->cmdp[13] = (unsigned char) (nr_blocks & 0xff);
+		}
 	}
 
+	hdr->timeout = SCSI_TIMEOUT_MS;
 	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;
+	int ret, do_sync = 0;
+
+	fio_ro_check(td, io_u);
+
+	if (td->o.sync_io || td->o.odirect || ddir_sync(io_u->ddir))
+		do_sync = 1;
 
-	ret = fio_sgio_doio(td, io_u, io_u->ddir == DDIR_SYNC);
+	ret = fio_sgio_doio(td, io_u, do_sync);
 
 	if (ret < 0)
 		io_u->error = errno;
@@ -266,7 +356,12 @@ static int fio_sgio_queue(struct thread_data *td, struct io_u *io_u)
 		io_u->error = EIO;
 	}
 
-	return io_u->error;
+	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)
@@ -276,102 +371,423 @@ static struct io_u *fio_sgio_event(struct thread_data *td, int event)
 	return sd->events[event];
 }
 
-static int fio_sgio_get_bs(struct thread_data *td, unsigned int *bs)
+static int fio_sgio_read_capacity(struct thread_data *td, unsigned int *bs,
+				  unsigned long long *max_lba)
 {
-	struct sgio_data *sd = td->io_ops->data;
-	struct io_u *io_u;
-	struct sg_io_hdr *hdr;
-	unsigned char buf[8];
+	/*
+	 * need to do read capacity operation w/o benefit of sd or
+	 * io_u structures, which are not initialized until later.
+	 */
+	struct sg_io_hdr hdr;
+	unsigned char cmd[16];
+	unsigned char sb[64];
+	unsigned char buf[32];  // read capacity return
 	int ret;
+	int fd = -1;
 
-	io_u = __get_io_u(td);
-	io_u->file = &td->files[0];
-	assert(io_u);
+	struct fio_file *f = td->files[0];
 
-	hdr = &io_u->hdr;
-	sgio_hdr_init(sd, hdr, io_u, 0);
-	memset(buf, 0, sizeof(buf));
+	/* open file independent of rest of application */
+	fd = open(f->file_name, O_RDONLY);
+	if (fd < 0)
+		return -errno;
 
-	hdr->cmdp[0] = 0x25;
-	hdr->dxfer_direction = SG_DXFER_FROM_DEV;
-	hdr->dxferp = buf;
-	hdr->dxfer_len = sizeof(buf);
+	memset(&hdr, 0, sizeof(hdr));
+	memset(cmd, 0, sizeof(cmd));
+	memset(sb, 0, sizeof(sb));
+	memset(buf, 0, sizeof(buf));
 
-	ret = fio_sgio_doio(td, io_u, 1);
-	if (ret) {
-		put_io_u(td, io_u);
+	/* First let's try a 10 byte read capacity. */
+	hdr.interface_id = 'S';
+	hdr.cmdp = cmd;
+	hdr.cmd_len = 10;
+	hdr.sbp = sb;
+	hdr.mx_sb_len = sizeof(sb);
+	hdr.timeout = SCSI_TIMEOUT_MS;
+	hdr.cmdp[0] = 0x25;  // Read Capacity(10)
+	hdr.dxfer_direction = SG_DXFER_FROM_DEV;
+	hdr.dxferp = buf;
+	hdr.dxfer_len = sizeof(buf);
+
+	ret = ioctl(fd, SG_IO, &hdr);
+	if (ret < 0) {
+		close(fd);
 		return ret;
 	}
 
-	*bs = (buf[4] << 24) | (buf[5] << 16) | (buf[6] << 8) | buf[7];
-	put_io_u(td, io_u);
+	*bs	 = (buf[4] << 24) | (buf[5] << 16) | (buf[6] << 8) | buf[7];
+	*max_lba = ((buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3]) & 0x00000000FFFFFFFFULL;  // for some reason max_lba is being sign extended even though unsigned.
+
+
+	/*
+	 * If max lba is 0xFFFFFFFF, then need to retry with
+	 * 16 byteread capacity
+	 */
+	if (*max_lba == MAX_10B_LBA) {
+		hdr.cmd_len = 16;
+		hdr.cmdp[0] = 0x9e; // Read Capacity(16)
+		hdr.cmdp[1] = 0x10; // service action
+		hdr.cmdp[10] = (unsigned char) ((sizeof(buf) >> 24) & 0xff);
+		hdr.cmdp[11] = (unsigned char) ((sizeof(buf) >> 16) & 0xff);
+		hdr.cmdp[12] = (unsigned char) ((sizeof(buf) >> 8) & 0xff);
+		hdr.cmdp[13] = (unsigned char) (sizeof(buf) & 0xff);
+
+		hdr.dxfer_direction = SG_DXFER_FROM_DEV;
+		hdr.dxferp = buf;
+		hdr.dxfer_len = sizeof(buf);
+
+		ret = ioctl(fd, SG_IO, &hdr);
+		if (ret < 0) {
+			close(fd);
+			return ret;
+		}
+
+		/* record if an io error occurred */
+		if (hdr.info & SG_INFO_CHECK)
+			td_verror(td, EIO, "fio_sgio_read_capacity");
+
+		*bs = (buf[8] << 24) | (buf[9] << 16) | (buf[10] << 8) | buf[11];
+		*max_lba = ((unsigned long long)buf[0] << 56) |
+				((unsigned long long)buf[1] << 48) |
+				((unsigned long long)buf[2] << 40) |
+				((unsigned long long)buf[3] << 32) |
+				((unsigned long long)buf[4] << 24) |
+				((unsigned long long)buf[5] << 16) |
+				((unsigned long long)buf[6] << 8) |
+				(unsigned long long)buf[7];
+	}
+
+	close(fd);
 	return 0;
 }
 
 static void fio_sgio_cleanup(struct thread_data *td)
 {
-	if (td->io_ops->data) {
-		free(td->io_ops->data);
-		td->io_ops->data = NULL;
+	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);
 	}
 }
 
 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->cmds = malloc(td->o.iodepth * sizeof(struct sgio_cmd));
+	memset(sd->cmds, 0, td->o.iodepth * sizeof(struct sgio_cmd));
+	sd->events = malloc(td->o.iodepth * sizeof(struct io_u *));
+	memset(sd->events, 0, td->o.iodepth * sizeof(struct io_u *));
+	sd->pfds = malloc(sizeof(struct pollfd) * td->o.nr_files);
+	memset(sd->pfds, 0, sizeof(struct pollfd) * td->o.nr_files);
+	sd->fd_flags = malloc(sizeof(int) * td->o.nr_files);
+	memset(sd->fd_flags, 0, sizeof(int) * td->o.nr_files);
+	sd->sgbuf = malloc(sizeof(struct sg_io_hdr) * td->o.iodepth);
+	memset(sd->sgbuf, 0, sizeof(struct sg_io_hdr) * td->o.iodepth);
+	sd->type_checked = 0;
 	td->io_ops->data = sd;
 
-	if (td->filetype == FIO_TYPE_BD) {
+	/*
+	 * we want to do it, regardless of whether odirect is set or not
+	 */
+	td->o.override_sync = 1;
+	return 0;
+}
+
+static int fio_sgio_type_check(struct thread_data *td, struct fio_file *f)
+{
+	struct sgio_data *sd = td->io_ops->data;
+	unsigned int bs = 0;
+	unsigned long long max_lba = 0;
+
+
+	if (f->filetype == FIO_TYPE_BD) {
 		if (ioctl(f->fd, BLKSSZGET, &bs) < 0) {
-			td_verror(td, errno);
-			goto err;
+			td_verror(td, errno, "ioctl");
+			return 1;
 		}
-	} else if (td->filetype == FIO_TYPE_CHAR) {
-		int version;
+	} else if (f->filetype == FIO_TYPE_CHAR) {
+		int version, ret;
 
 		if (ioctl(f->fd, SG_GET_VERSION_NUM, &version) < 0) {
-			td_verror(td, errno);
-			goto err;
+			td_verror(td, errno, "ioctl");
+			return 1;
 		}
 
-		ret = fio_sgio_get_bs(td, &bs);
-		if (ret)
-			goto err;
+		ret = fio_sgio_read_capacity(td, &bs, &max_lba);
+		if (ret) {
+			td_verror(td, td->error, "fio_sgio_read_capacity");
+			log_err("ioengine sg unable to read capacity successfully\n");
+			return 1;
+		}
 	} else {
-		log_err("ioengine sgio only works on block devices\n");
-		goto err;
+		td_verror(td, EINVAL, "wrong file type");
+		log_err("ioengine sg only works on block devices\n");
+		return 1;
 	}
 
 	sd->bs = bs;
+	// Determine size of commands needed based on max_lba
+	sd->max_lba = max_lba;
+	if (max_lba > MAX_10B_LBA) {
+		dprint(FD_IO, "sgio_type_check: using 16 byte operations: max_lba = 0x%016llx\n", max_lba);
+	}
+
+
+	if (f->filetype == FIO_TYPE_BD) {
+		td->io_ops->getevents = NULL;
+		td->io_ops->event = NULL;
+	}
+	sd->type_checked = 1;
+
+	return 0;
+}
+
+static int fio_sgio_open(struct thread_data *td, struct fio_file *f)
+{
+	struct sgio_data *sd = td->io_ops->data;
+	int ret;
 
-	if (td->filetype == FIO_TYPE_BD)
-		td->io_ops->getevents = fio_sgio_ioctl_getevents;
-	else
-		td->io_ops->getevents = fio_sgio_getevents;
+	ret = generic_open_file(td, f);
+	if (ret)
+		return ret;
+
+	if (sd && !sd->type_checked && fio_sgio_type_check(td, f)) {
+		ret = generic_close_file(td, f);
+		return 1;
+	}
+
+	return 0;
+}
+
+/*
+ * Build an error string with details about the driver, host or scsi
+ * error contained in the sg header Caller will use as necessary.
+ */
+static char *fio_sgio_errdetails(struct io_u *io_u)
+{
+	struct sg_io_hdr *hdr = &io_u->hdr;
+#define MAXERRDETAIL 1024
+#define MAXMSGCHUNK  128
+	char *msg, msgchunk[MAXMSGCHUNK], *ret = NULL;
+	int i;
+
+	msg = calloc(MAXERRDETAIL, 1);
 
 	/*
-	 * we want to do it, regardless of whether odirect is set or not
+	 * can't seem to find sg_err.h, so I'll just echo the define values
+	 * so others can search on internet to find clearer clues of meaning.
+	 */
+	if (hdr->info & SG_INFO_CHECK) {
+		ret = msg;
+		if (hdr->host_status) {
+			snprintf(msgchunk, MAXMSGCHUNK, "SG Host Status: 0x%02x; ", hdr->host_status);
+			strlcat(msg, msgchunk, MAXERRDETAIL);
+			switch (hdr->host_status) {
+			case 0x01:
+				strlcat(msg, "SG_ERR_DID_NO_CONNECT", MAXERRDETAIL);
+				break;
+			case 0x02:
+				strlcat(msg, "SG_ERR_DID_BUS_BUSY", MAXERRDETAIL);
+				break;
+			case 0x03:
+				strlcat(msg, "SG_ERR_DID_TIME_OUT", MAXERRDETAIL);
+				break;
+			case 0x04:
+				strlcat(msg, "SG_ERR_DID_BAD_TARGET", MAXERRDETAIL);
+				break;
+			case 0x05:
+				strlcat(msg, "SG_ERR_DID_ABORT", MAXERRDETAIL);
+				break;
+			case 0x06:
+				strlcat(msg, "SG_ERR_DID_PARITY", MAXERRDETAIL);
+				break;
+			case 0x07:
+				strlcat(msg, "SG_ERR_DID_ERROR (internal error)", MAXERRDETAIL);
+				break;
+			case 0x08:
+				strlcat(msg, "SG_ERR_DID_RESET", MAXERRDETAIL);
+				break;
+			case 0x09:
+				strlcat(msg, "SG_ERR_DID_BAD_INTR (unexpected)", MAXERRDETAIL);
+				break;
+			case 0x0a:
+				strlcat(msg, "SG_ERR_DID_PASSTHROUGH", MAXERRDETAIL);
+				break;
+			case 0x0b:
+				strlcat(msg, "SG_ERR_DID_SOFT_ERROR (driver retry?)", MAXERRDETAIL);
+				break;
+			case 0x0c:
+				strlcat(msg, "SG_ERR_DID_IMM_RETRY", MAXERRDETAIL);
+				break;
+			case 0x0d:
+				strlcat(msg, "SG_ERR_DID_REQUEUE", MAXERRDETAIL);
+				break;
+			default:
+				strlcat(msg, "Unknown", MAXERRDETAIL);
+				break;
+			}
+			strlcat(msg, ". ", MAXERRDETAIL);
+		}
+		if (hdr->driver_status) {
+			snprintf(msgchunk, MAXMSGCHUNK, "SG Driver Status: 0x%02x; ", hdr->driver_status);
+			strlcat(msg, msgchunk, MAXERRDETAIL);
+			switch (hdr->driver_status & 0x0F) {
+			case 0x01:
+				strlcat(msg, "SG_ERR_DRIVER_BUSY", MAXERRDETAIL);
+				break;
+			case 0x02:
+				strlcat(msg, "SG_ERR_DRIVER_SOFT", MAXERRDETAIL);
+				break;
+			case 0x03:
+				strlcat(msg, "SG_ERR_DRIVER_MEDIA", MAXERRDETAIL);
+				break;
+			case 0x04:
+				strlcat(msg, "SG_ERR_DRIVER_ERROR", MAXERRDETAIL);
+				break;
+			case 0x05:
+				strlcat(msg, "SG_ERR_DRIVER_INVALID", MAXERRDETAIL);
+				break;
+			case 0x06:
+				strlcat(msg, "SG_ERR_DRIVER_TIMEOUT", MAXERRDETAIL);
+				break;
+			case 0x07:
+				strlcat(msg, "SG_ERR_DRIVER_HARD", MAXERRDETAIL);
+				break;
+			case 0x08:
+				strlcat(msg, "SG_ERR_DRIVER_SENSE", MAXERRDETAIL);
+				break;
+			default:
+				strlcat(msg, "Unknown", MAXERRDETAIL);
+				break;
+			}
+			strlcat(msg, "; ", MAXERRDETAIL);
+			switch (hdr->driver_status & 0xF0) {
+			case 0x10:
+				strlcat(msg, "SG_ERR_SUGGEST_RETRY", MAXERRDETAIL);
+				break;
+			case 0x20:
+				strlcat(msg, "SG_ERR_SUGGEST_ABORT", MAXERRDETAIL);
+				break;
+			case 0x30:
+				strlcat(msg, "SG_ERR_SUGGEST_REMAP", MAXERRDETAIL);
+				break;
+			case 0x40:
+				strlcat(msg, "SG_ERR_SUGGEST_DIE", MAXERRDETAIL);
+				break;
+			case 0x80:
+				strlcat(msg, "SG_ERR_SUGGEST_SENSE", MAXERRDETAIL);
+				break;
+			}
+			strlcat(msg, ". ", MAXERRDETAIL);
+		}
+		if (hdr->status) {
+			snprintf(msgchunk, MAXMSGCHUNK, "SG SCSI Status: 0x%02x; ", hdr->status);
+			strlcat(msg, msgchunk, MAXERRDETAIL);
+			// SCSI 3 status codes
+			switch (hdr->status) {
+			case 0x02:
+				strlcat(msg, "CHECK_CONDITION", MAXERRDETAIL);
+				break;
+			case 0x04:
+				strlcat(msg, "CONDITION_MET", MAXERRDETAIL);
+				break;
+			case 0x08:
+				strlcat(msg, "BUSY", MAXERRDETAIL);
+				break;
+			case 0x10:
+				strlcat(msg, "INTERMEDIATE", MAXERRDETAIL);
+				break;
+			case 0x14:
+				strlcat(msg, "INTERMEDIATE_CONDITION_MET", MAXERRDETAIL);
+				break;
+			case 0x18:
+				strlcat(msg, "RESERVATION_CONFLICT", MAXERRDETAIL);
+				break;
+			case 0x22:
+				strlcat(msg, "COMMAND_TERMINATED", MAXERRDETAIL);
+				break;
+			case 0x28:
+				strlcat(msg, "TASK_SET_FULL", MAXERRDETAIL);
+				break;
+			case 0x30:
+				strlcat(msg, "ACA_ACTIVE", MAXERRDETAIL);
+				break;
+			case 0x40:
+				strlcat(msg, "TASK_ABORTED", MAXERRDETAIL);
+				break;
+			default:
+				strlcat(msg, "Unknown", MAXERRDETAIL);
+				break;
+			}
+			strlcat(msg, ". ", MAXERRDETAIL);
+		}
+		if (hdr->sb_len_wr) {
+			snprintf(msgchunk, MAXMSGCHUNK, "Sense Data (%d bytes):", hdr->sb_len_wr);
+			strlcat(msg, msgchunk, MAXERRDETAIL);
+			for (i = 0; i < hdr->sb_len_wr; i++) {
+				snprintf(msgchunk, MAXMSGCHUNK, " %02x", hdr->sbp[i]);
+				strlcat(msg, msgchunk, MAXERRDETAIL);
+			}
+			strlcat(msg, ". ", MAXERRDETAIL);
+		}
+		if (hdr->resid != 0) {
+			snprintf(msgchunk, MAXMSGCHUNK, "SG Driver: %d bytes out of %d not transferred. ", hdr->resid, hdr->dxfer_len);
+			strlcat(msg, msgchunk, MAXERRDETAIL);
+			ret = msg;
+		}
+	}
+
+	if (!ret)
+		ret = strdup("SG Driver did not report a Host, Driver or Device check");
+
+	return ret;
+}
+
+/*
+ * get max file size from read capacity.
+ */
+static int fio_sgio_get_file_size(struct thread_data *td, struct fio_file *f)
+{
+	/*
+	 * get_file_size is being called even before sgio_init is
+	 * called, so none of the sg_io structures are
+	 * initialized in the thread_data yet.  So we need to do the
+	 * ReadCapacity without any of those helpers.  One of the effects
+	 * is that ReadCapacity may get called 4 times on each open:
+	 * readcap(10) followed by readcap(16) if needed - just to get
+	 * the file size after the init occurs - it will be called
+	 * again when "type_check" is called during structure
+	 * initialization I'm not sure how to prevent this little
+	 * inefficiency.
 	 */
-	td->override_sync = 1;
+	unsigned int bs = 0;
+	unsigned long long max_lba = 0;
+	int ret;
+
+	if (fio_file_size_known(f))
+		return 0;
+
+	ret = fio_sgio_read_capacity(td, &bs, &max_lba);
+	if (ret ) {
+		td_verror(td, td->error, "fio_sgio_read_capacity");
+		log_err("ioengine sg unable to successfully execute read capacity to get block size and maximum lba\n");
+		return 1;
+	}
+
+	f->real_file_size = (max_lba + 1) * bs;
+	fio_file_set_size_known(f);
 	return 0;
-err:
-	free(sd->events);
-	free(sd->cmds);
-	free(sd);
-	td->io_ops->data = NULL;
-	return 1;
 }
 
+
 static struct ioengine_ops ioengine = {
 	.name		= "sg",
 	.version	= FIO_IOOPS_VERSION,
@@ -379,8 +795,12 @@ static struct ioengine_ops ioengine = {
 	.prep		= fio_sgio_prep,
 	.queue		= fio_sgio_queue,
 	.getevents	= fio_sgio_getevents,
+	.errdetails	= fio_sgio_errdetails,
 	.event		= fio_sgio_event,
 	.cleanup	= fio_sgio_cleanup,
+	.open_file	= fio_sgio_open,
+	.close_file	= generic_close_file,
+	.get_file_size	= fio_sgio_get_file_size, // generic_get_file_size
 	.flags		= FIO_SYNCIO | FIO_RAWIO,
 };
 
@@ -393,12 +813,12 @@ static struct ioengine_ops ioengine = {
  */
 static int fio_sgio_init(struct thread_data fio_unused *td)
 {
-	fprintf(stderr, "fio: sgio not available\n");
+	log_err("fio: ioengine sg not available\n");
 	return 1;
 }
 
 static struct ioengine_ops ioengine = {
-	.name		= "sgio",
+	.name		= "sg",
 	.version	= FIO_IOOPS_VERSION,
 	.init		= fio_sgio_init,
 };