xref: /freebsd/sys/cam/scsi/scsi_sg.c (revision bfe691b2f75de2224c7ceb304ebcdef2b42d4179)
1 /*-
2  * Copyright (c) 2007 Scott Long
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions, and the following disclaimer,
10  *    without modification, immediately at the beginning of the file.
11  * 2. The name of the author may not be used to endorse or promote products
12  *    derived from this software without specific prior written permission.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
18  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 /*
28  * scsi_sg peripheral driver.  This driver is meant to implement the Linux
29  * SG passthrough interface for SCSI.
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/types.h>
39 #include <sys/bio.h>
40 #include <sys/malloc.h>
41 #include <sys/fcntl.h>
42 #include <sys/ioccom.h>
43 #include <sys/conf.h>
44 #include <sys/errno.h>
45 #include <sys/devicestat.h>
46 #include <sys/proc.h>
47 #include <sys/uio.h>
48 
49 #include <cam/cam.h>
50 #include <cam/cam_ccb.h>
51 #include <cam/cam_periph.h>
52 #include <cam/cam_queue.h>
53 #include <cam/cam_xpt_periph.h>
54 #include <cam/cam_debug.h>
55 #include <cam/cam_sim.h>
56 
57 #include <cam/scsi/scsi_all.h>
58 #include <cam/scsi/scsi_message.h>
59 #include <cam/scsi/scsi_sg.h>
60 
61 #include <compat/linux/linux_ioctl.h>
62 
63 typedef enum {
64 	SG_FLAG_OPEN		= 0x01,
65 	SG_FLAG_LOCKED		= 0x02,
66 	SG_FLAG_INVALID		= 0x04
67 } sg_flags;
68 
69 typedef enum {
70 	SG_STATE_NORMAL
71 } sg_state;
72 
73 typedef enum {
74 	SG_RDWR_INPROG,
75 	SG_RDWR_WAITING,
76 	SG_RDWR_DONE
77 } sg_rdwr_state;
78 
79 typedef enum {
80 	SG_CCB_RDWR_IO,
81 	SG_CCB_WAITING
82 } sg_ccb_types;
83 
84 #define ccb_type	ppriv_field0
85 #define ccb_rdwr	ppriv_ptr1
86 
87 struct sg_rdwr {
88 	TAILQ_ENTRY(sg_rdwr)	rdwr_link;
89 	int			tag;
90 	int			state;
91 	int			buf_len;
92 	char			*buf;
93 	union ccb		*ccb;
94 	union {
95 		struct sg_header hdr;
96 		struct sg_io_hdr io_hdr;
97 	} hdr;
98 };
99 
100 struct sg_softc {
101 	sg_state		state;
102 	sg_flags		flags;
103 	uint8_t			pd_type;
104 	struct devstat		*device_stats;
105 	TAILQ_HEAD(, sg_rdwr)	rdwr_done;
106 	struct cdev		*dev;
107 	struct cdev		*devalias;
108 	union ccb		saved_ccb;
109 };
110 
111 static d_open_t		sgopen;
112 static d_close_t	sgclose;
113 static d_ioctl_t	sgioctl;
114 static d_write_t	sgwrite;
115 static d_read_t		sgread;
116 
117 static periph_init_t	sginit;
118 static periph_ctor_t	sgregister;
119 static periph_oninv_t	sgoninvalidate;
120 static periph_dtor_t	sgcleanup;
121 static periph_start_t	sgstart;
122 static void		sgasync(void *callback_arg, uint32_t code,
123 				struct cam_path *path, void *arg);
124 static void		sgdone(struct cam_periph *periph, union ccb *done_ccb);
125 static int		sgsendccb(struct cam_periph *periph, union ccb *ccb);
126 static int		sgsendrdwr(struct cam_periph *periph, union ccb *ccb);
127 static int		sgerror(union ccb *ccb, uint32_t cam_flags,
128 				uint32_t sense_flags);
129 static void		sg_scsiio_status(struct ccb_scsiio *csio,
130 					 u_short *hoststat, u_short *drvstat);
131 
132 static int		scsi_group_len(u_char cmd);
133 
134 static struct periph_driver sgdriver =
135 {
136 	sginit, "sg",
137 	TAILQ_HEAD_INITIALIZER(sgdriver.units), /* gen */ 0
138 };
139 PERIPHDRIVER_DECLARE(sg, sgdriver);
140 
141 static struct cdevsw sg_cdevsw = {
142 	.d_version =	D_VERSION,
143 	.d_flags =	D_NEEDGIANT,
144 	.d_open =	sgopen,
145 	.d_close =	sgclose,
146 	.d_ioctl =	sgioctl,
147 	.d_write =	sgwrite,
148 	.d_read =	sgread,
149 	.d_name =	"sg",
150 };
151 
152 static int sg_version = 30125;
153 
154 static void
155 sginit(void)
156 {
157 	cam_status status;
158 	struct cam_path *path;
159 
160 	/*
161 	 * Install a global async callback.  This callback will receive aync
162 	 * callbacks like "new device found".
163 	 */
164 	status = xpt_create_path(&path, /*periph*/NULL, CAM_XPT_PATH_ID,
165 				 CAM_TARGET_WILDCARD, CAM_LUN_WILDCARD);
166 
167 	if (status == CAM_REQ_CMP) {
168 		struct ccb_setasync csa;
169 
170 		xpt_setup_ccb(&csa.ccb_h, path, /*priority*/5);
171 		csa.ccb_h.func_code = XPT_SASYNC_CB;
172 		csa.event_enable = AC_FOUND_DEVICE;
173 		csa.callback = sgasync;
174 		csa.callback_arg = NULL;
175 		xpt_action((union ccb *)&csa);
176 		status = csa.ccb_h.status;
177 		xpt_free_path(path);
178 	}
179 
180 	if (status != CAM_REQ_CMP) {
181 		printf("sg: Failed to attach master async callbac "
182 			"due to status 0x%x!\n", status);
183 	}
184 }
185 
186 static void
187 sgoninvalidate(struct cam_periph *periph)
188 {
189 	struct sg_softc *softc;
190 	struct ccb_setasync csa;
191 
192 	softc = (struct sg_softc *)periph->softc;
193 
194 	/*
195 	 * Deregister any async callbacks.
196 	 */
197 	xpt_setup_ccb(&csa.ccb_h, periph->path, /*priority*/5);
198 	csa.ccb_h.func_code = XPT_SASYNC_CB;
199 	csa.event_enable = 0;
200 	csa.callback = sgasync;
201 	csa.callback_arg = periph;
202 	xpt_action((union ccb *)&csa);
203 
204 	softc->flags |= SG_FLAG_INVALID;
205 
206 	/*
207 	 * XXX Return all queued I/O with ENXIO.
208 	 * XXX Handle any transactions queued to the card
209 	 *     with XPT_ABORT_CCB.
210 	 */
211 
212 	if (bootverbose) {
213 		xpt_print(periph->path, "lost device\n");
214 	}
215 }
216 
217 static void
218 sgcleanup(struct cam_periph *periph)
219 {
220 	struct sg_softc *softc;
221 
222 	softc = (struct sg_softc *)periph->softc;
223 	devstat_remove_entry(softc->device_stats);
224 	destroy_dev(softc->dev);
225 	destroy_dev(softc->devalias);
226 	if (bootverbose) {
227 		xpt_print(periph->path, "removing device entry\n");
228 	}
229 	free(softc, M_DEVBUF);
230 }
231 
232 static void
233 sgasync(void *callback_arg, uint32_t code, struct cam_path *path, void *arg)
234 {
235 	struct cam_periph *periph;
236 
237 	periph = (struct cam_periph *)callback_arg;
238 
239 	switch (code) {
240 	case AC_FOUND_DEVICE:
241 	{
242 		struct ccb_getdev *cgd;
243 		cam_status status;
244 
245 		cgd = (struct ccb_getdev *)arg;
246 		if (cgd == NULL)
247 			break;
248 
249 		/*
250 		 * Allocate a peripheral instance for this device and
251 		 * start the probe process.
252 		 */
253 		status = cam_periph_alloc(sgregister, sgoninvalidate,
254 					  sgcleanup, sgstart, "sg",
255 					  CAM_PERIPH_BIO, cgd->ccb_h.path,
256 					  sgasync, AC_FOUND_DEVICE, cgd);
257 		if ((status != CAM_REQ_CMP) && (status != CAM_REQ_INPROG)) {
258 			const struct cam_status_entry *entry;
259 
260 			entry = cam_fetch_status_entry(status);
261 			printf("sgasync: Unable to attach new device "
262 				"due to status %#x: %s\n", status, entry ?
263 				entry->status_text : "Unknown");
264 		}
265 		break;
266 	}
267 	default:
268 		cam_periph_async(periph, code, path, arg);
269 		break;
270 	}
271 }
272 
273 static cam_status
274 sgregister(struct cam_periph *periph, void *arg)
275 {
276 	struct sg_softc *softc;
277 	struct ccb_setasync csa;
278 	struct ccb_getdev *cgd;
279 	int no_tags;
280 
281 	cgd = (struct ccb_getdev *)arg;
282 	if (periph == NULL) {
283 		printf("sgregister: periph was NULL!!\n");
284 		return (CAM_REQ_CMP_ERR);
285 	}
286 
287 	if (cgd == NULL) {
288 		printf("sgregister: no getdev CCB, can't register device\n");
289 		return (CAM_REQ_CMP_ERR);
290 	}
291 
292 	softc = (struct sg_softc *)malloc(sizeof(*softc), M_DEVBUF, M_NOWAIT);
293 	if (softc == NULL) {
294 		printf("sgregister: Unable to allocate softc\n");
295 		return (CAM_REQ_CMP_ERR);
296 	}
297 
298 	bzero(softc, sizeof(*softc));
299 	softc->state = SG_STATE_NORMAL;
300 	softc->pd_type = SID_TYPE(&cgd->inq_data);
301 	TAILQ_INIT(&softc->rdwr_done);
302 	periph->softc = softc;
303 
304 	/*
305 	 * We pass in 0 for all blocksize, since we don't know what the
306 	 * blocksize of the device is, if it even has a blocksize.
307 	 */
308 	no_tags = (cgd->inq_data.flags & SID_CmdQue) == 0;
309 	softc->device_stats = devstat_new_entry("sg",
310 			unit2minor(periph->unit_number), 0,
311 			DEVSTAT_NO_BLOCKSIZE
312 			| (no_tags ? DEVSTAT_NO_ORDERED_TAGS : 0),
313 			softc->pd_type |
314 			DEVSTAT_TYPE_IF_SCSI |
315 			DEVSTAT_TYPE_PASS,
316 			DEVSTAT_PRIORITY_PASS);
317 
318 	/* Register the device */
319 	softc->dev = make_dev(&sg_cdevsw, unit2minor(periph->unit_number),
320 			      UID_ROOT, GID_OPERATOR, 0600, "%s%d",
321 			      periph->periph_name, periph->unit_number);
322 	softc->devalias = make_dev_alias(softc->dev, "sg%c",
323 					 'a' + periph->unit_number);
324 	softc->dev->si_drv1 = periph;
325 
326 	/*
327 	 * Add as async callback so that we get
328 	 * notified if this device goes away.
329 	 */
330 	xpt_setup_ccb(&csa.ccb_h, periph->path, /*priority*/5);
331 	csa.ccb_h.func_code = XPT_SASYNC_CB;
332 	csa.event_enable = AC_LOST_DEVICE;
333 	csa.callback = sgasync;
334 	csa.callback_arg = periph;
335 	xpt_action((union ccb *)&csa);
336 
337 	if (bootverbose)
338 		xpt_announce_periph(periph, NULL);
339 
340 	return (CAM_REQ_CMP);
341 }
342 
343 static void
344 sgstart(struct cam_periph *periph, union ccb *start_ccb)
345 {
346 	struct sg_softc *softc;
347 
348 	softc = (struct sg_softc *)periph->softc;
349 
350 	switch (softc->state) {
351 	case SG_STATE_NORMAL:
352 		start_ccb->ccb_h.ccb_type = SG_CCB_WAITING;
353 		SLIST_INSERT_HEAD(&periph->ccb_list, &start_ccb->ccb_h,
354 				  periph_links.sle);
355 		periph->immediate_priority = CAM_PRIORITY_NONE;
356 		wakeup(&periph->ccb_list);
357 		break;
358 	}
359 }
360 
361 static void
362 sgdone(struct cam_periph *periph, union ccb *done_ccb)
363 {
364 	struct sg_softc *softc;
365 	struct ccb_scsiio *csio;
366 
367 	softc = (struct sg_softc *)periph->softc;
368 	csio = &done_ccb->csio;
369 	switch (csio->ccb_h.ccb_type) {
370 	case SG_CCB_WAITING:
371 		/* Caller will release the CCB */
372 		wakeup(&done_ccb->ccb_h.cbfcnp);
373 		return;
374 	case SG_CCB_RDWR_IO:
375 	{
376 		struct sg_rdwr *rdwr;
377 		int state;
378 
379 		devstat_end_transaction(softc->device_stats,
380 					csio->dxfer_len,
381 					csio->tag_action & 0xf,
382 					((csio->ccb_h.flags & CAM_DIR_MASK) ==
383 					CAM_DIR_NONE) ? DEVSTAT_NO_DATA :
384 					(csio->ccb_h.flags & CAM_DIR_OUT) ?
385 					DEVSTAT_WRITE : DEVSTAT_READ,
386 					NULL, NULL);
387 
388 		rdwr = done_ccb->ccb_h.ccb_rdwr;
389 		state = rdwr->state;
390 		rdwr->state = SG_RDWR_DONE;
391 		if (state == SG_RDWR_WAITING)
392 			wakeup(rdwr);
393 		break;
394 	}
395 	default:
396 		panic("unknown sg CCB type");
397 	}
398 }
399 
400 static int
401 sgopen(struct cdev *dev, int flags, int fmt, struct thread *td)
402 {
403 	struct cam_periph *periph;
404 	struct sg_softc *softc;
405 	int error = 0;
406 
407 	periph = (struct cam_periph *)dev->si_drv1;
408 	if (periph == NULL)
409 		return (ENXIO);
410 
411 	softc = (struct sg_softc *)periph->softc;
412 	if (softc->flags & SG_FLAG_INVALID)
413 		return (ENXIO);
414 
415 	/*
416 	 * Don't allow access when we're running at a high securelevel.
417 	 */
418 	error = securelevel_gt(td->td_ucred, 1);
419 	if (error)
420 		return (error);
421 
422 	if ((error = cam_periph_lock(periph, PRIBIO | PCATCH)) != 0)
423 		return (error);
424 
425 	if ((softc->flags & SG_FLAG_OPEN) == 0) {
426 		if (cam_periph_acquire(periph) != CAM_REQ_CMP)
427 			return (ENXIO);
428 		softc->flags |= SG_FLAG_OPEN;
429 	}
430 
431 	cam_periph_unlock(periph);
432 
433 	return (error);
434 }
435 
436 static int
437 sgclose(struct cdev *dev, int flag, int fmt, struct thread *td)
438 {
439 	struct cam_periph *periph;
440 	struct sg_softc *softc;
441 	int error;
442 
443 	periph = (struct cam_periph *)dev->si_drv1;
444 	if (periph == NULL)
445 		return (ENXIO);
446 
447 	softc = (struct sg_softc *)periph->softc;
448 
449 	if ((error = cam_periph_lock(periph, PRIBIO)) != 0)
450 		return (error);
451 
452 	softc->flags &= ~SG_FLAG_OPEN;
453 
454 	cam_periph_unlock(periph);
455 	cam_periph_release(periph);
456 
457 	return (0);
458 }
459 
460 static int
461 sgioctl(struct cdev *dev, u_long cmd, caddr_t arg, int flag, struct thread *td)
462 {
463 	union ccb *ccb;
464 	struct ccb_scsiio *csio;
465 	struct cam_periph *periph;
466 	struct sg_softc *softc;
467 	struct sg_io_hdr req;
468 	int dir, error;
469 
470 	periph = (struct cam_periph *)dev->si_drv1;
471 	if (periph == NULL)
472 		return (ENXIO);
473 
474 	softc = (struct sg_softc *)periph->softc;
475 	error = 0;
476 
477 	switch (cmd) {
478 	case LINUX_SCSI_GET_BUS_NUMBER: {
479 		int busno;
480 
481 		busno = xpt_path_path_id(periph->path);
482 		error = copyout(&busno, arg, sizeof(busno));
483 		break;
484 	}
485 	case LINUX_SCSI_GET_IDLUN: {
486 		struct scsi_idlun idlun;
487 		struct cam_sim *sim;
488 
489 		idlun.dev_id = xpt_path_target_id(periph->path);
490 		sim = xpt_path_sim(periph->path);
491 		idlun.host_unique_id = sim->unit_number;
492 		error = copyout(&idlun, arg, sizeof(idlun));
493 		break;
494 	}
495 	case SG_GET_VERSION_NUM:
496 	case LINUX_SG_GET_VERSION_NUM:
497 		error = copyout(&sg_version, arg, sizeof(sg_version));
498 		break;
499 	case SG_SET_TIMEOUT:
500 	case LINUX_SG_SET_TIMEOUT:
501 		break;
502 	case SG_GET_TIMEOUT:
503 	case LINUX_SG_GET_TIMEOUT:
504 		/*
505 		 * XXX This ioctl is highly brain damaged because it requires
506 		 *     that the value be returned in the syscall return value.
507 		 *     The linuxolator seems to have a hard time with this,
508 		 *     so just return 0 and hope that apps can cope.
509 		 */
510 		error = 0;
511 		break;
512 	case SG_IO:
513 	case LINUX_SG_IO:
514 		error = copyin(arg, &req, sizeof(req));
515 		if (error)
516 			break;
517 
518 		if (req.cmd_len > IOCDBLEN) {
519 			error = EINVAL;
520 			break;
521 		}
522 
523 		if (req.iovec_count != 0) {
524 			error = EOPNOTSUPP;
525 			break;
526 		}
527 
528 		ccb = cam_periph_getccb(periph, /*priority*/5);
529 		csio = &ccb->csio;
530 
531 		error = copyin(req.cmdp, &csio->cdb_io.cdb_bytes,
532 		    req.cmd_len);
533 		if (error) {
534 			xpt_release_ccb(ccb);
535 			break;
536 		}
537 
538 		switch(req.dxfer_direction) {
539 		case SG_DXFER_TO_DEV:
540 			dir = CAM_DIR_OUT;
541 			break;
542 		case SG_DXFER_FROM_DEV:
543 			dir = CAM_DIR_IN;
544 			break;
545 		case SG_DXFER_TO_FROM_DEV:
546 			dir = CAM_DIR_IN | CAM_DIR_OUT;
547 			break;
548 		case SG_DXFER_NONE:
549 		default:
550 			dir = CAM_DIR_NONE;
551 			break;
552 		}
553 
554 		cam_fill_csio(csio,
555 			      /*retries*/1,
556 			      sgdone,
557 			      dir|CAM_DEV_QFRZDIS,
558 			      MSG_SIMPLE_Q_TAG,
559 			      req.dxferp,
560 			      req.dxfer_len,
561 			      req.mx_sb_len,
562 			      req.cmd_len,
563 			      req.timeout);
564 
565 		error = sgsendccb(periph, ccb);
566 		if (error) {
567 			req.host_status = DID_ERROR;
568 			req.driver_status = DRIVER_INVALID;
569 			xpt_release_ccb(ccb);
570 			break;
571 		}
572 
573 		req.status = csio->scsi_status;
574 		req.masked_status = (csio->scsi_status >> 1) & 0x7f;
575 		sg_scsiio_status(csio, &req.host_status, &req.driver_status);
576 		req.resid = csio->resid;
577 		req.duration = csio->ccb_h.timeout;
578 		req.info = 0;
579 
580 		error = copyout(&req, arg, sizeof(req));
581 		if ((error == 0) && (csio->ccb_h.status & CAM_AUTOSNS_VALID)
582 		    && (req.sbp != NULL)) {
583 			req.sb_len_wr = req.mx_sb_len - csio->sense_resid;
584 			error = copyout(&csio->sense_data, req.sbp,
585 					req.sb_len_wr);
586 		}
587 
588 		xpt_release_ccb(ccb);
589 		break;
590 
591 	case SG_GET_RESERVED_SIZE:
592 	case LINUX_SG_GET_RESERVED_SIZE: {
593 		int size = 32768;
594 
595 		error = copyout(&size, arg, sizeof(size));
596 		break;
597 	}
598 
599 	case SG_GET_SCSI_ID:
600 	case LINUX_SG_GET_SCSI_ID:
601 	{
602 		struct sg_scsi_id id;
603 
604 		id.host_no = 0; /* XXX */
605 		id.channel = xpt_path_path_id(periph->path);
606 		id.scsi_id = xpt_path_target_id(periph->path);
607 		id.lun = xpt_path_lun_id(periph->path);
608 		id.scsi_type = softc->pd_type;
609 		id.h_cmd_per_lun = 1;
610 		id.d_queue_depth = 1;
611 		id.unused[0] = 0;
612 		id.unused[1] = 0;
613 
614 		error = copyout(&id, arg, sizeof(id));
615 		break;
616 	}
617 
618 	case SG_EMULATED_HOST:
619 	case SG_SET_TRANSFORM:
620 	case SG_GET_TRANSFORM:
621 	case SG_GET_NUM_WAITING:
622 	case SG_SCSI_RESET:
623 	case SG_GET_REQUEST_TABLE:
624 	case SG_SET_KEEP_ORPHAN:
625 	case SG_GET_KEEP_ORPHAN:
626 	case SG_GET_ACCESS_COUNT:
627 	case SG_SET_FORCE_LOW_DMA:
628 	case SG_GET_LOW_DMA:
629 	case SG_GET_SG_TABLESIZE:
630 	case SG_SET_FORCE_PACK_ID:
631 	case SG_GET_PACK_ID:
632 	case SG_SET_RESERVED_SIZE:
633 	case SG_GET_COMMAND_Q:
634 	case SG_SET_COMMAND_Q:
635 	case SG_SET_DEBUG:
636 	case SG_NEXT_CMD_LEN:
637 	case LINUX_SG_EMULATED_HOST:
638 	case LINUX_SG_SET_TRANSFORM:
639 	case LINUX_SG_GET_TRANSFORM:
640 	case LINUX_SG_GET_NUM_WAITING:
641 	case LINUX_SG_SCSI_RESET:
642 	case LINUX_SG_GET_REQUEST_TABLE:
643 	case LINUX_SG_SET_KEEP_ORPHAN:
644 	case LINUX_SG_GET_KEEP_ORPHAN:
645 	case LINUX_SG_GET_ACCESS_COUNT:
646 	case LINUX_SG_SET_FORCE_LOW_DMA:
647 	case LINUX_SG_GET_LOW_DMA:
648 	case LINUX_SG_GET_SG_TABLESIZE:
649 	case LINUX_SG_SET_FORCE_PACK_ID:
650 	case LINUX_SG_GET_PACK_ID:
651 	case LINUX_SG_SET_RESERVED_SIZE:
652 	case LINUX_SG_GET_COMMAND_Q:
653 	case LINUX_SG_SET_COMMAND_Q:
654 	case LINUX_SG_SET_DEBUG:
655 	case LINUX_SG_NEXT_CMD_LEN:
656 	default:
657 #ifdef CAMDEBUG
658 		printf("sgioctl: rejecting cmd 0x%lx\n", cmd);
659 #endif
660 		error = ENODEV;
661 		break;
662 	}
663 
664 	return (error);
665 }
666 
667 static int
668 sgwrite(struct cdev *dev, struct uio *uio, int ioflag)
669 {
670 	union ccb *ccb;
671 	struct cam_periph *periph;
672 	struct ccb_scsiio *csio;
673 	struct sg_softc *sc;
674 	struct sg_header *hdr;
675 	struct sg_rdwr *rdwr;
676 	u_char cdb_cmd;
677 	char *buf;
678 	int error = 0, cdb_len, buf_len, dir;
679 
680 	periph = dev->si_drv1;
681 	sc = periph->softc;
682 	rdwr = malloc(sizeof(*rdwr), M_DEVBUF, M_WAITOK);
683 	hdr = &rdwr->hdr.hdr;
684 
685 	/* Copy in the header block and sanity check it */
686 	if (uio->uio_resid < sizeof(*hdr)) {
687 		error = EINVAL;
688 		goto out_hdr;
689 	}
690 	error = uiomove(hdr, sizeof(*hdr), uio);
691 	if (error)
692 		goto out_hdr;
693 
694 	ccb = xpt_alloc_ccb();
695 	if (ccb == NULL) {
696 		error = ENOMEM;
697 		goto out_hdr;
698 	}
699 	xpt_setup_ccb(&ccb->ccb_h, periph->path, /*priority*/5);
700 	csio = &ccb->csio;
701 
702 	/*
703 	 * Copy in the CDB block.  The designers of the interface didn't
704 	 * bother to provide a size for this in the header, so we have to
705 	 * figure it out ourselves.
706 	 */
707 	if (uio->uio_resid < 1)
708 		goto out_ccb;
709 	error = uiomove(&cdb_cmd, 1, uio);
710 	if (error)
711 		goto out_ccb;
712 	if (hdr->twelve_byte)
713 		cdb_len = 12;
714 	else
715 		cdb_len = scsi_group_len(cdb_cmd);
716 	/*
717 	 * We've already read the first byte of the CDB and advanced the uio
718 	 * pointer.  Just read the rest.
719 	 */
720 	csio->cdb_io.cdb_bytes[0] = cdb_cmd;
721 	error = uiomove(&csio->cdb_io.cdb_bytes[1], cdb_len - 1, uio);
722 	if (error)
723 		goto out_ccb;
724 
725 	/*
726 	 * Now set up the data block.  Again, the designers didn't bother
727 	 * to make this reliable.
728 	 */
729 	buf_len = uio->uio_resid;
730 	if (buf_len != 0) {
731 		buf = malloc(buf_len, M_DEVBUF, M_WAITOK);
732 		error = uiomove(buf, buf_len, uio);
733 		if (error)
734 			goto out_buf;
735 		dir = CAM_DIR_OUT;
736 	} else if (hdr->reply_len != 0) {
737 		buf = malloc(hdr->reply_len, M_DEVBUF, M_WAITOK);
738 		buf_len = hdr->reply_len;
739 		dir = CAM_DIR_IN;
740 	} else {
741 		buf = NULL;
742 		buf_len = 0;
743 		dir = CAM_DIR_NONE;
744 	}
745 
746 	cam_fill_csio(csio,
747 		      /*retries*/1,
748 		      sgdone,
749 		      dir|CAM_DEV_QFRZDIS,
750 		      MSG_SIMPLE_Q_TAG,
751 		      buf,
752 		      buf_len,
753 		      SG_MAX_SENSE,
754 		      cdb_len,
755 		      60*hz);
756 
757 	/*
758 	 * Send off the command and hope that it works. This path does not
759 	 * go through sgstart because the I/O is supposed to be asynchronous.
760 	 */
761 	rdwr->buf = buf;
762 	rdwr->buf_len = buf_len;
763 	rdwr->tag = hdr->pack_id;
764 	rdwr->ccb = ccb;
765 	rdwr->state = SG_RDWR_INPROG;
766 	ccb->ccb_h.ccb_rdwr = rdwr;
767 	ccb->ccb_h.ccb_type = SG_CCB_RDWR_IO;
768 	TAILQ_INSERT_TAIL(&sc->rdwr_done, rdwr, rdwr_link);
769 	return (sgsendrdwr(periph, ccb));
770 
771 out_buf:
772 	free(buf, M_DEVBUF);
773 out_ccb:
774 	xpt_free_ccb(ccb);
775 out_hdr:
776 	free(rdwr, M_DEVBUF);
777 	return (error);
778 }
779 
780 static int
781 sgread(struct cdev *dev, struct uio *uio, int ioflag)
782 {
783 	struct ccb_scsiio *csio;
784 	struct cam_periph *periph;
785 	struct sg_softc *sc;
786 	struct sg_header *hdr;
787 	struct sg_rdwr *rdwr;
788 	u_short hstat, dstat;
789 	int error, pack_len, reply_len, pack_id;
790 
791 	periph = dev->si_drv1;
792 	sc = periph->softc;
793 
794 	/* XXX The pack len field needs to be updated and written out instead
795 	 * of discarded.  Not sure how to do that.
796 	 */
797 	uio->uio_rw = UIO_WRITE;
798 	if ((error = uiomove(&pack_len, 4, uio)) != 0)
799 		return (error);
800 	if ((error = uiomove(&reply_len, 4, uio)) != 0)
801 		return (error);
802 	if ((error = uiomove(&pack_id, 4, uio)) != 0)
803 		return (error);
804 	uio->uio_rw = UIO_READ;
805 
806 search:
807 	TAILQ_FOREACH(rdwr, &sc->rdwr_done, rdwr_link) {
808 		if (rdwr->tag == pack_id)
809 			break;
810 	}
811 	if ((rdwr == NULL) || (rdwr->state != SG_RDWR_DONE)) {
812 		rdwr->state = SG_RDWR_WAITING;
813 		if (tsleep(rdwr, PCATCH, "sgread", 0) == ERESTART)
814 			return (EAGAIN);
815 		goto search;
816 	}
817 	TAILQ_REMOVE(&sc->rdwr_done, rdwr, rdwr_link);
818 
819 	hdr = &rdwr->hdr.hdr;
820 	csio = &rdwr->ccb->csio;
821 	sg_scsiio_status(csio, &hstat, &dstat);
822 	hdr->host_status = hstat;
823 	hdr->driver_status = dstat;
824 	hdr->target_status = csio->scsi_status >> 1;
825 
826 	switch (hstat) {
827 	case DID_OK:
828 	case DID_PASSTHROUGH:
829 	case DID_SOFT_ERROR:
830 		hdr->result = 0;
831 		break;
832 	case DID_NO_CONNECT:
833 	case DID_BUS_BUSY:
834 	case DID_TIME_OUT:
835 		hdr->result = EBUSY;
836 		break;
837 	case DID_BAD_TARGET:
838 	case DID_ABORT:
839 	case DID_PARITY:
840 	case DID_RESET:
841 	case DID_BAD_INTR:
842 	case DID_ERROR:
843 	default:
844 		hdr->result = EIO;
845 		break;
846 	}
847 
848 	if (dstat == DRIVER_SENSE) {
849 		bcopy(&csio->sense_data, hdr->sense_buffer,
850 		      min(csio->sense_len, SG_MAX_SENSE));
851 #ifdef CAMDEBUG
852 		scsi_sense_print(csio);
853 #endif
854 	}
855 
856 	error = uiomove(&hdr->result, sizeof(*hdr) -
857 			offsetof(struct sg_header, result), uio);
858 	if ((error == 0) && (hdr->result == 0))
859 		error = uiomove(rdwr->buf, rdwr->buf_len, uio);
860 
861 	xpt_free_ccb(rdwr->ccb);
862 	free(rdwr->buf, M_DEVBUF);
863 	free(rdwr, M_DEVBUF);
864 	return (error);
865 }
866 
867 static int
868 sgsendccb(struct cam_periph *periph, union ccb *ccb)
869 {
870 	struct sg_softc *softc;
871 	struct cam_periph_map_info mapinfo;
872 	int error, need_unmap = 0;
873 
874 	softc = periph->softc;
875 	if (((ccb->ccb_h.flags & CAM_DIR_MASK) != CAM_DIR_NONE)
876 	    && (ccb->csio.data_ptr != NULL)) {
877 		bzero(&mapinfo, sizeof(mapinfo));
878 		error = cam_periph_mapmem(ccb, &mapinfo);
879 		if (error)
880 			return (error);
881 		need_unmap = 1;
882 	}
883 
884 	error = cam_periph_runccb(ccb,
885 				  sgerror,
886 				  CAM_RETRY_SELTO,
887 				  SF_RETRY_UA,
888 				  softc->device_stats);
889 
890 	if (need_unmap)
891 		cam_periph_unmapmem(ccb, &mapinfo);
892 
893 	return (error);
894 }
895 
896 static int
897 sgsendrdwr(struct cam_periph *periph, union ccb *ccb)
898 {
899 	struct sg_softc *softc;
900 
901 	softc = periph->softc;
902 	devstat_start_transaction(softc->device_stats, NULL);
903 	xpt_action(ccb);
904 	return (0);
905 }
906 
907 static int
908 sgerror(union ccb *ccb, uint32_t cam_flags, uint32_t sense_flags)
909 {
910 	struct cam_periph *periph;
911 	struct sg_softc *softc;
912 
913 	periph = xpt_path_periph(ccb->ccb_h.path);
914 	softc = (struct sg_softc *)periph->softc;
915 
916 	return (cam_periph_error(ccb, cam_flags, sense_flags,
917 				 &softc->saved_ccb));
918 }
919 
920 static void
921 sg_scsiio_status(struct ccb_scsiio *csio, u_short *hoststat, u_short *drvstat)
922 {
923 	int status;
924 
925 	status = csio->ccb_h.status;
926 
927 	switch (status & CAM_STATUS_MASK) {
928 	case CAM_REQ_CMP:
929 		*hoststat = DID_OK;
930 		*drvstat = 0;
931 		break;
932 	case CAM_REQ_CMP_ERR:
933 		*hoststat = DID_ERROR;
934 		*drvstat = 0;
935 		break;
936 	case CAM_REQ_ABORTED:
937 		*hoststat = DID_ABORT;
938 		*drvstat = 0;
939 		break;
940 	case CAM_REQ_INVALID:
941 		*hoststat = DID_ERROR;
942 		*drvstat = DRIVER_INVALID;
943 		break;
944 	case CAM_DEV_NOT_THERE:
945 		*hoststat = DID_BAD_TARGET;
946 		*drvstat = 0;
947 	case CAM_SEL_TIMEOUT:
948 		*hoststat = DID_NO_CONNECT;
949 		*drvstat = 0;
950 		break;
951 	case CAM_CMD_TIMEOUT:
952 		*hoststat = DID_TIME_OUT;
953 		*drvstat = 0;
954 		break;
955 	case CAM_SCSI_STATUS_ERROR:
956 		*hoststat = DID_ERROR;
957 		*drvstat = 0;
958 	case CAM_SCSI_BUS_RESET:
959 		*hoststat = DID_RESET;
960 		*drvstat = 0;
961 		break;
962 	case CAM_UNCOR_PARITY:
963 		*hoststat = DID_PARITY;
964 		*drvstat = 0;
965 		break;
966 	case CAM_SCSI_BUSY:
967 		*hoststat = DID_BUS_BUSY;
968 		*drvstat = 0;
969 	default:
970 		*hoststat = DID_ERROR;
971 		*drvstat = DRIVER_ERROR;
972 	}
973 
974 	if (status & CAM_AUTOSNS_VALID)
975 		*drvstat = DRIVER_SENSE;
976 }
977 
978 static int
979 scsi_group_len(u_char cmd)
980 {
981 	int len[] = {6, 10, 10, 12, 12, 12, 10, 10};
982 	int group;
983 
984 	group = (cmd >> 5) & 0x7;
985 	return (len[group]);
986 }
987 
988