scsi_sg.c revision 168752
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: head/sys/cam/scsi/scsi_sg.c 168752 2007-04-15 08:49:19Z scottl $");
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
63typedef enum {
64	SG_FLAG_OPEN		= 0x01,
65	SG_FLAG_LOCKED		= 0x02,
66	SG_FLAG_INVALID		= 0x04
67} sg_flags;
68
69typedef enum {
70	SG_STATE_NORMAL
71} sg_state;
72
73typedef enum {
74	SG_RDWR_FREE,
75	SG_RDWR_INPROG,
76	SG_RDWR_DONE
77} sg_rdwr_state;
78
79typedef 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
87struct 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
100struct sg_softc {
101	sg_state		state;
102	sg_flags		flags;
103	struct devstat		*device_stats;
104	TAILQ_HEAD(, sg_rdwr)	rdwr_done;
105	struct cdev		*dev;
106	struct cdev		*devalias;
107	int			sg_timeout;
108	int			sg_user_timeout;
109	uint8_t			pd_type;
110	union ccb		saved_ccb;
111};
112
113static d_open_t		sgopen;
114static d_close_t	sgclose;
115static d_ioctl_t	sgioctl;
116static d_write_t	sgwrite;
117static d_read_t		sgread;
118
119static periph_init_t	sginit;
120static periph_ctor_t	sgregister;
121static periph_oninv_t	sgoninvalidate;
122static periph_dtor_t	sgcleanup;
123static periph_start_t	sgstart;
124static void		sgasync(void *callback_arg, uint32_t code,
125				struct cam_path *path, void *arg);
126static void		sgdone(struct cam_periph *periph, union ccb *done_ccb);
127static int		sgsendccb(struct cam_periph *periph, union ccb *ccb);
128static int		sgsendrdwr(struct cam_periph *periph, union ccb *ccb);
129static int		sgerror(union ccb *ccb, uint32_t cam_flags,
130				uint32_t sense_flags);
131static void		sg_scsiio_status(struct ccb_scsiio *csio,
132					 u_short *hoststat, u_short *drvstat);
133
134static int		scsi_group_len(u_char cmd);
135
136static struct periph_driver sgdriver =
137{
138	sginit, "sg",
139	TAILQ_HEAD_INITIALIZER(sgdriver.units), /* gen */ 0
140};
141PERIPHDRIVER_DECLARE(sg, sgdriver);
142
143static struct cdevsw sg_cdevsw = {
144	.d_version =	D_VERSION,
145	.d_flags =	D_NEEDGIANT,
146	.d_open =	sgopen,
147	.d_close =	sgclose,
148	.d_ioctl =	sgioctl,
149	.d_write =	sgwrite,
150	.d_read =	sgread,
151	.d_name =	"sg",
152};
153
154static int sg_version = 30125;
155
156static void
157sginit(void)
158{
159	cam_status status;
160	struct cam_path *path;
161
162	/*
163	 * Install a global async callback.  This callback will receive aync
164	 * callbacks like "new device found".
165	 */
166	status = xpt_create_path(&path, /*periph*/NULL, CAM_XPT_PATH_ID,
167				 CAM_TARGET_WILDCARD, CAM_LUN_WILDCARD);
168
169	if (status == CAM_REQ_CMP) {
170		struct ccb_setasync csa;
171
172		xpt_setup_ccb(&csa.ccb_h, path, /*priority*/5);
173		csa.ccb_h.func_code = XPT_SASYNC_CB;
174		csa.event_enable = AC_FOUND_DEVICE;
175		csa.callback = sgasync;
176		csa.callback_arg = NULL;
177		xpt_action((union ccb *)&csa);
178		status = csa.ccb_h.status;
179		xpt_free_path(path);
180	}
181
182	if (status != CAM_REQ_CMP) {
183		printf("sg: Failed to attach master async callbac "
184			"due to status 0x%x!\n", status);
185	}
186}
187
188static void
189sgoninvalidate(struct cam_periph *periph)
190{
191	struct sg_softc *softc;
192	struct ccb_setasync csa;
193
194	softc = (struct sg_softc *)periph->softc;
195
196	/*
197	 * Deregister any async callbacks.
198	 */
199	xpt_setup_ccb(&csa.ccb_h, periph->path, /*priority*/5);
200	csa.ccb_h.func_code = XPT_SASYNC_CB;
201	csa.event_enable = 0;
202	csa.callback = sgasync;
203	csa.callback_arg = periph;
204	xpt_action((union ccb *)&csa);
205
206	softc->flags |= SG_FLAG_INVALID;
207
208	/*
209	 * XXX Return all queued I/O with ENXIO.
210	 * XXX Handle any transactions queued to the card
211	 *     with XPT_ABORT_CCB.
212	 */
213
214	if (bootverbose) {
215		xpt_print(periph->path, "lost device\n");
216	}
217}
218
219static void
220sgcleanup(struct cam_periph *periph)
221{
222	struct sg_softc *softc;
223
224	softc = (struct sg_softc *)periph->softc;
225	devstat_remove_entry(softc->device_stats);
226	destroy_dev(softc->dev);
227	destroy_dev(softc->devalias);
228	if (bootverbose) {
229		xpt_print(periph->path, "removing device entry\n");
230	}
231	free(softc, M_DEVBUF);
232}
233
234static void
235sgasync(void *callback_arg, uint32_t code, struct cam_path *path, void *arg)
236{
237	struct cam_periph *periph;
238
239	periph = (struct cam_periph *)callback_arg;
240
241	switch (code) {
242	case AC_FOUND_DEVICE:
243	{
244		struct ccb_getdev *cgd;
245		cam_status status;
246
247		cgd = (struct ccb_getdev *)arg;
248		if (cgd == NULL)
249			break;
250
251		/*
252		 * Allocate a peripheral instance for this device and
253		 * start the probe process.
254		 */
255		status = cam_periph_alloc(sgregister, sgoninvalidate,
256					  sgcleanup, sgstart, "sg",
257					  CAM_PERIPH_BIO, cgd->ccb_h.path,
258					  sgasync, AC_FOUND_DEVICE, cgd);
259		if ((status != CAM_REQ_CMP) && (status != CAM_REQ_INPROG)) {
260			const struct cam_status_entry *entry;
261
262			entry = cam_fetch_status_entry(status);
263			printf("sgasync: Unable to attach new device "
264				"due to status %#x: %s\n", status, entry ?
265				entry->status_text : "Unknown");
266		}
267		break;
268	}
269	default:
270		cam_periph_async(periph, code, path, arg);
271		break;
272	}
273}
274
275static cam_status
276sgregister(struct cam_periph *periph, void *arg)
277{
278	struct sg_softc *softc;
279	struct ccb_setasync csa;
280	struct ccb_getdev *cgd;
281	int no_tags;
282
283	cgd = (struct ccb_getdev *)arg;
284	if (periph == NULL) {
285		printf("sgregister: periph was NULL!!\n");
286		return (CAM_REQ_CMP_ERR);
287	}
288
289	if (cgd == NULL) {
290		printf("sgregister: no getdev CCB, can't register device\n");
291		return (CAM_REQ_CMP_ERR);
292	}
293
294	softc = malloc(sizeof(*softc), M_DEVBUF, M_ZERO | M_NOWAIT);
295	if (softc == NULL) {
296		printf("sgregister: Unable to allocate softc\n");
297		return (CAM_REQ_CMP_ERR);
298	}
299
300	softc->state = SG_STATE_NORMAL;
301	softc->pd_type = SID_TYPE(&cgd->inq_data);
302	softc->sg_timeout = SG_DEFAULT_TIMEOUT / SG_DEFAULT_HZ * hz;
303	softc->sg_user_timeout = SG_DEFAULT_TIMEOUT;
304	TAILQ_INIT(&softc->rdwr_done);
305	periph->softc = softc;
306
307	/*
308	 * We pass in 0 for all blocksize, since we don't know what the
309	 * blocksize of the device is, if it even has a blocksize.
310	 */
311	no_tags = (cgd->inq_data.flags & SID_CmdQue) == 0;
312	softc->device_stats = devstat_new_entry("sg",
313			unit2minor(periph->unit_number), 0,
314			DEVSTAT_NO_BLOCKSIZE
315			| (no_tags ? DEVSTAT_NO_ORDERED_TAGS : 0),
316			softc->pd_type |
317			DEVSTAT_TYPE_IF_SCSI |
318			DEVSTAT_TYPE_PASS,
319			DEVSTAT_PRIORITY_PASS);
320
321	/* Register the device */
322	cam_periph_unlock(periph);
323	softc->dev = make_dev(&sg_cdevsw, unit2minor(periph->unit_number),
324			      UID_ROOT, GID_OPERATOR, 0600, "%s%d",
325			      periph->periph_name, periph->unit_number);
326	softc->devalias = make_dev_alias(softc->dev, "sg%c",
327					 'a' + periph->unit_number);
328	cam_periph_lock(periph);
329	softc->dev->si_drv1 = periph;
330
331	/*
332	 * Add as async callback so that we get
333	 * notified if this device goes away.
334	 */
335	xpt_setup_ccb(&csa.ccb_h, periph->path, /*priority*/5);
336	csa.ccb_h.func_code = XPT_SASYNC_CB;
337	csa.event_enable = AC_LOST_DEVICE;
338	csa.callback = sgasync;
339	csa.callback_arg = periph;
340	xpt_action((union ccb *)&csa);
341
342	if (bootverbose)
343		xpt_announce_periph(periph, NULL);
344
345	return (CAM_REQ_CMP);
346}
347
348static void
349sgstart(struct cam_periph *periph, union ccb *start_ccb)
350{
351	struct sg_softc *softc;
352
353	softc = (struct sg_softc *)periph->softc;
354
355	switch (softc->state) {
356	case SG_STATE_NORMAL:
357		start_ccb->ccb_h.ccb_type = SG_CCB_WAITING;
358		SLIST_INSERT_HEAD(&periph->ccb_list, &start_ccb->ccb_h,
359				  periph_links.sle);
360		periph->immediate_priority = CAM_PRIORITY_NONE;
361		wakeup(&periph->ccb_list);
362		break;
363	}
364}
365
366static void
367sgdone(struct cam_periph *periph, union ccb *done_ccb)
368{
369	struct sg_softc *softc;
370	struct ccb_scsiio *csio;
371
372	softc = (struct sg_softc *)periph->softc;
373	csio = &done_ccb->csio;
374	switch (csio->ccb_h.ccb_type) {
375	case SG_CCB_WAITING:
376		/* Caller will release the CCB */
377		wakeup(&done_ccb->ccb_h.cbfcnp);
378		return;
379	case SG_CCB_RDWR_IO:
380	{
381		struct sg_rdwr *rdwr;
382		int state;
383
384		devstat_end_transaction(softc->device_stats,
385					csio->dxfer_len,
386					csio->tag_action & 0xf,
387					((csio->ccb_h.flags & CAM_DIR_MASK) ==
388					CAM_DIR_NONE) ? DEVSTAT_NO_DATA :
389					(csio->ccb_h.flags & CAM_DIR_OUT) ?
390					DEVSTAT_WRITE : DEVSTAT_READ,
391					NULL, NULL);
392
393		rdwr = done_ccb->ccb_h.ccb_rdwr;
394		state = rdwr->state;
395		rdwr->state = SG_RDWR_DONE;
396		wakeup(rdwr);
397		break;
398	}
399	default:
400		panic("unknown sg CCB type");
401	}
402}
403
404static int
405sgopen(struct cdev *dev, int flags, int fmt, struct thread *td)
406{
407	struct cam_periph *periph;
408	struct sg_softc *softc;
409	int error = 0;
410
411	periph = (struct cam_periph *)dev->si_drv1;
412	if (periph == NULL)
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	cam_periph_lock(periph);
423
424	softc = (struct sg_softc *)periph->softc;
425	if (softc->flags & SG_FLAG_INVALID) {
426		cam_periph_unlock(periph);
427		return (ENXIO);
428	}
429
430	if ((softc->flags & SG_FLAG_OPEN) == 0) {
431		softc->flags |= SG_FLAG_OPEN;
432	} else {
433		/* Device closes aren't symmetrical, fix up the refcount. */
434		cam_periph_release(periph);
435	}
436
437	cam_periph_unlock(periph);
438
439	return (error);
440}
441
442static int
443sgclose(struct cdev *dev, int flag, int fmt, struct thread *td)
444{
445	struct cam_periph *periph;
446	struct sg_softc *softc;
447
448	periph = (struct cam_periph *)dev->si_drv1;
449	if (periph == NULL)
450		return (ENXIO);
451
452	cam_periph_lock(periph);
453
454	softc = (struct sg_softc *)periph->softc;
455	softc->flags &= ~SG_FLAG_OPEN;
456
457	cam_periph_unlock(periph);
458	cam_periph_release(periph);
459
460	return (0);
461}
462
463static int
464sgioctl(struct cdev *dev, u_long cmd, caddr_t arg, int flag, struct thread *td)
465{
466	union ccb *ccb;
467	struct ccb_scsiio *csio;
468	struct cam_periph *periph;
469	struct sg_softc *softc;
470	struct sg_io_hdr req;
471	int dir, error;
472
473	periph = (struct cam_periph *)dev->si_drv1;
474	if (periph == NULL)
475		return (ENXIO);
476
477	cam_periph_lock(periph);
478
479	softc = (struct sg_softc *)periph->softc;
480	error = 0;
481
482	switch (cmd) {
483	case LINUX_SCSI_GET_BUS_NUMBER: {
484		int busno;
485
486		busno = xpt_path_path_id(periph->path);
487		error = copyout(&busno, arg, sizeof(busno));
488		break;
489	}
490	case LINUX_SCSI_GET_IDLUN: {
491		struct scsi_idlun idlun;
492		struct cam_sim *sim;
493
494		idlun.dev_id = xpt_path_target_id(periph->path);
495		sim = xpt_path_sim(periph->path);
496		idlun.host_unique_id = sim->unit_number;
497		error = copyout(&idlun, arg, sizeof(idlun));
498		break;
499	}
500	case SG_GET_VERSION_NUM:
501	case LINUX_SG_GET_VERSION_NUM:
502		error = copyout(&sg_version, arg, sizeof(sg_version));
503		break;
504	case SG_SET_TIMEOUT:
505	case LINUX_SG_SET_TIMEOUT: {
506		u_int user_timeout;
507
508		error = copyin(arg, &user_timeout, sizeof(u_int));
509		if (error == 0) {
510			softc->sg_user_timeout = user_timeout;
511			softc->sg_timeout = user_timeout / SG_DEFAULT_HZ * hz;
512		}
513		break;
514	}
515	case SG_GET_TIMEOUT:
516	case LINUX_SG_GET_TIMEOUT:
517		/*
518		 * The value is returned directly to the syscall.
519		 */
520		td->td_retval[0] = softc->sg_user_timeout;
521		error = 0;
522		break;
523	case SG_IO:
524	case LINUX_SG_IO:
525		error = copyin(arg, &req, sizeof(req));
526		if (error)
527			break;
528
529		if (req.cmd_len > IOCDBLEN) {
530			error = EINVAL;
531			break;
532		}
533
534		if (req.iovec_count != 0) {
535			error = EOPNOTSUPP;
536			break;
537		}
538
539		ccb = cam_periph_getccb(periph, /*priority*/5);
540		csio = &ccb->csio;
541
542		error = copyin(req.cmdp, &csio->cdb_io.cdb_bytes,
543		    req.cmd_len);
544		if (error) {
545			xpt_release_ccb(ccb);
546			break;
547		}
548
549		switch(req.dxfer_direction) {
550		case SG_DXFER_TO_DEV:
551			dir = CAM_DIR_OUT;
552			break;
553		case SG_DXFER_FROM_DEV:
554			dir = CAM_DIR_IN;
555			break;
556		case SG_DXFER_TO_FROM_DEV:
557			dir = CAM_DIR_IN | CAM_DIR_OUT;
558			break;
559		case SG_DXFER_NONE:
560		default:
561			dir = CAM_DIR_NONE;
562			break;
563		}
564
565		cam_fill_csio(csio,
566			      /*retries*/1,
567			      sgdone,
568			      dir|CAM_DEV_QFRZDIS,
569			      MSG_SIMPLE_Q_TAG,
570			      req.dxferp,
571			      req.dxfer_len,
572			      req.mx_sb_len,
573			      req.cmd_len,
574			      req.timeout);
575
576		error = sgsendccb(periph, ccb);
577		if (error) {
578			req.host_status = DID_ERROR;
579			req.driver_status = DRIVER_INVALID;
580			xpt_release_ccb(ccb);
581			break;
582		}
583
584		req.status = csio->scsi_status;
585		req.masked_status = (csio->scsi_status >> 1) & 0x7f;
586		sg_scsiio_status(csio, &req.host_status, &req.driver_status);
587		req.resid = csio->resid;
588		req.duration = csio->ccb_h.timeout;
589		req.info = 0;
590
591		error = copyout(&req, arg, sizeof(req));
592		if ((error == 0) && (csio->ccb_h.status & CAM_AUTOSNS_VALID)
593		    && (req.sbp != NULL)) {
594			req.sb_len_wr = req.mx_sb_len - csio->sense_resid;
595			error = copyout(&csio->sense_data, req.sbp,
596					req.sb_len_wr);
597		}
598
599		xpt_release_ccb(ccb);
600		break;
601
602	case SG_GET_RESERVED_SIZE:
603	case LINUX_SG_GET_RESERVED_SIZE: {
604		int size = 32768;
605
606		error = copyout(&size, arg, sizeof(size));
607		break;
608	}
609
610	case SG_GET_SCSI_ID:
611	case LINUX_SG_GET_SCSI_ID:
612	{
613		struct sg_scsi_id id;
614
615		id.host_no = 0; /* XXX */
616		id.channel = xpt_path_path_id(periph->path);
617		id.scsi_id = xpt_path_target_id(periph->path);
618		id.lun = xpt_path_lun_id(periph->path);
619		id.scsi_type = softc->pd_type;
620		id.h_cmd_per_lun = 1;
621		id.d_queue_depth = 1;
622		id.unused[0] = 0;
623		id.unused[1] = 0;
624
625		error = copyout(&id, arg, sizeof(id));
626		break;
627	}
628
629	case SG_EMULATED_HOST:
630	case SG_SET_TRANSFORM:
631	case SG_GET_TRANSFORM:
632	case SG_GET_NUM_WAITING:
633	case SG_SCSI_RESET:
634	case SG_GET_REQUEST_TABLE:
635	case SG_SET_KEEP_ORPHAN:
636	case SG_GET_KEEP_ORPHAN:
637	case SG_GET_ACCESS_COUNT:
638	case SG_SET_FORCE_LOW_DMA:
639	case SG_GET_LOW_DMA:
640	case SG_GET_SG_TABLESIZE:
641	case SG_SET_FORCE_PACK_ID:
642	case SG_GET_PACK_ID:
643	case SG_SET_RESERVED_SIZE:
644	case SG_GET_COMMAND_Q:
645	case SG_SET_COMMAND_Q:
646	case SG_SET_DEBUG:
647	case SG_NEXT_CMD_LEN:
648	case LINUX_SG_EMULATED_HOST:
649	case LINUX_SG_SET_TRANSFORM:
650	case LINUX_SG_GET_TRANSFORM:
651	case LINUX_SG_GET_NUM_WAITING:
652	case LINUX_SG_SCSI_RESET:
653	case LINUX_SG_GET_REQUEST_TABLE:
654	case LINUX_SG_SET_KEEP_ORPHAN:
655	case LINUX_SG_GET_KEEP_ORPHAN:
656	case LINUX_SG_GET_ACCESS_COUNT:
657	case LINUX_SG_SET_FORCE_LOW_DMA:
658	case LINUX_SG_GET_LOW_DMA:
659	case LINUX_SG_GET_SG_TABLESIZE:
660	case LINUX_SG_SET_FORCE_PACK_ID:
661	case LINUX_SG_GET_PACK_ID:
662	case LINUX_SG_SET_RESERVED_SIZE:
663	case LINUX_SG_GET_COMMAND_Q:
664	case LINUX_SG_SET_COMMAND_Q:
665	case LINUX_SG_SET_DEBUG:
666	case LINUX_SG_NEXT_CMD_LEN:
667	default:
668#ifdef CAMDEBUG
669		printf("sgioctl: rejecting cmd 0x%lx\n", cmd);
670#endif
671		error = ENODEV;
672		break;
673	}
674
675	cam_periph_unlock(periph);
676	return (error);
677}
678
679static int
680sgwrite(struct cdev *dev, struct uio *uio, int ioflag)
681{
682	union ccb *ccb;
683	struct cam_periph *periph;
684	struct ccb_scsiio *csio;
685	struct sg_softc *sc;
686	struct sg_header *hdr;
687	struct sg_rdwr *rdwr;
688	u_char cdb_cmd;
689	char *buf;
690	int error = 0, cdb_len, buf_len, dir;
691
692	periph = dev->si_drv1;
693	rdwr = malloc(sizeof(*rdwr), M_DEVBUF, M_WAITOK | M_ZERO);
694	hdr = &rdwr->hdr.hdr;
695
696	/* Copy in the header block and sanity check it */
697	if (uio->uio_resid < sizeof(*hdr)) {
698		error = EINVAL;
699		goto out_hdr;
700	}
701	error = uiomove(hdr, sizeof(*hdr), uio);
702	if (error)
703		goto out_hdr;
704
705	ccb = xpt_alloc_ccb(periph->sim);
706	if (ccb == NULL) {
707		error = ENOMEM;
708		goto out_hdr;
709	}
710	csio = &ccb->csio;
711
712	/*
713	 * Copy in the CDB block.  The designers of the interface didn't
714	 * bother to provide a size for this in the header, so we have to
715	 * figure it out ourselves.
716	 */
717	if (uio->uio_resid < 1)
718		goto out_ccb;
719	error = uiomove(&cdb_cmd, 1, uio);
720	if (error)
721		goto out_ccb;
722	if (hdr->twelve_byte)
723		cdb_len = 12;
724	else
725		cdb_len = scsi_group_len(cdb_cmd);
726	/*
727	 * We've already read the first byte of the CDB and advanced the uio
728	 * pointer.  Just read the rest.
729	 */
730	csio->cdb_io.cdb_bytes[0] = cdb_cmd;
731	error = uiomove(&csio->cdb_io.cdb_bytes[1], cdb_len - 1, uio);
732	if (error)
733		goto out_ccb;
734
735	/*
736	 * Now set up the data block.  Again, the designers didn't bother
737	 * to make this reliable.
738	 */
739	buf_len = uio->uio_resid;
740	if (buf_len != 0) {
741		buf = malloc(buf_len, M_DEVBUF, M_WAITOK | M_ZERO);
742		error = uiomove(buf, buf_len, uio);
743		if (error)
744			goto out_buf;
745		dir = CAM_DIR_OUT;
746	} else if (hdr->reply_len != 0) {
747		buf = malloc(hdr->reply_len, M_DEVBUF, M_WAITOK | M_ZERO);
748		buf_len = hdr->reply_len;
749		dir = CAM_DIR_IN;
750	} else {
751		buf = NULL;
752		buf_len = 0;
753		dir = CAM_DIR_NONE;
754	}
755
756	cam_periph_lock(periph);
757	sc = periph->softc;
758	xpt_setup_ccb(&ccb->ccb_h, periph->path, /*priority*/5);
759	cam_fill_csio(csio,
760		      /*retries*/1,
761		      sgdone,
762		      dir|CAM_DEV_QFRZDIS,
763		      MSG_SIMPLE_Q_TAG,
764		      buf,
765		      buf_len,
766		      SG_MAX_SENSE,
767		      cdb_len,
768		      sc->sg_timeout);
769
770	/*
771	 * Send off the command and hope that it works. This path does not
772	 * go through sgstart because the I/O is supposed to be asynchronous.
773	 */
774	rdwr->buf = buf;
775	rdwr->buf_len = buf_len;
776	rdwr->tag = hdr->pack_id;
777	rdwr->ccb = ccb;
778	rdwr->state = SG_RDWR_INPROG;
779	ccb->ccb_h.ccb_rdwr = rdwr;
780	ccb->ccb_h.ccb_type = SG_CCB_RDWR_IO;
781	TAILQ_INSERT_TAIL(&sc->rdwr_done, rdwr, rdwr_link);
782	error = sgsendrdwr(periph, ccb);
783	cam_periph_unlock(periph);
784	return (error);
785
786out_buf:
787	free(buf, M_DEVBUF);
788out_ccb:
789	xpt_free_ccb(ccb);
790out_hdr:
791	free(rdwr, M_DEVBUF);
792	return (error);
793}
794
795static int
796sgread(struct cdev *dev, struct uio *uio, int ioflag)
797{
798	struct ccb_scsiio *csio;
799	struct cam_periph *periph;
800	struct sg_softc *sc;
801	struct sg_header *hdr;
802	struct sg_rdwr *rdwr;
803	u_short hstat, dstat;
804	int error, pack_len, reply_len, pack_id;
805
806	periph = dev->si_drv1;
807
808	/* XXX The pack len field needs to be updated and written out instead
809	 * of discarded.  Not sure how to do that.
810	 */
811	uio->uio_rw = UIO_WRITE;
812	if ((error = uiomove(&pack_len, 4, uio)) != 0)
813		return (error);
814	if ((error = uiomove(&reply_len, 4, uio)) != 0)
815		return (error);
816	if ((error = uiomove(&pack_id, 4, uio)) != 0)
817		return (error);
818	uio->uio_rw = UIO_READ;
819
820	cam_periph_lock(periph);
821	sc = periph->softc;
822search:
823	TAILQ_FOREACH(rdwr, &sc->rdwr_done, rdwr_link) {
824		if (rdwr->tag == pack_id)
825			break;
826	}
827	if ((rdwr == NULL) || (rdwr->state != SG_RDWR_DONE)) {
828		if (msleep(rdwr, periph->sim->mtx, PCATCH, "sgread", 0) == ERESTART)
829			return (EAGAIN);
830		goto search;
831	}
832	TAILQ_REMOVE(&sc->rdwr_done, rdwr, rdwr_link);
833	cam_periph_unlock(periph);
834
835	hdr = &rdwr->hdr.hdr;
836	csio = &rdwr->ccb->csio;
837	sg_scsiio_status(csio, &hstat, &dstat);
838	hdr->host_status = hstat;
839	hdr->driver_status = dstat;
840	hdr->target_status = csio->scsi_status >> 1;
841
842	switch (hstat) {
843	case DID_OK:
844	case DID_PASSTHROUGH:
845	case DID_SOFT_ERROR:
846		hdr->result = 0;
847		break;
848	case DID_NO_CONNECT:
849	case DID_BUS_BUSY:
850	case DID_TIME_OUT:
851		hdr->result = EBUSY;
852		break;
853	case DID_BAD_TARGET:
854	case DID_ABORT:
855	case DID_PARITY:
856	case DID_RESET:
857	case DID_BAD_INTR:
858	case DID_ERROR:
859	default:
860		hdr->result = EIO;
861		break;
862	}
863
864	if (dstat == DRIVER_SENSE) {
865		bcopy(&csio->sense_data, hdr->sense_buffer,
866		      min(csio->sense_len, SG_MAX_SENSE));
867#ifdef CAMDEBUG
868		scsi_sense_print(csio);
869#endif
870	}
871
872	error = uiomove(&hdr->result, sizeof(*hdr) -
873			offsetof(struct sg_header, result), uio);
874	if ((error == 0) && (hdr->result == 0))
875		error = uiomove(rdwr->buf, rdwr->buf_len, uio);
876
877	cam_periph_lock(periph);
878	xpt_free_ccb(rdwr->ccb);
879	cam_periph_unlock(periph);
880	free(rdwr->buf, M_DEVBUF);
881	free(rdwr, M_DEVBUF);
882	return (error);
883}
884
885static int
886sgsendccb(struct cam_periph *periph, union ccb *ccb)
887{
888	struct sg_softc *softc;
889	struct cam_periph_map_info mapinfo;
890	int error, need_unmap = 0;
891
892	softc = periph->softc;
893	if (((ccb->ccb_h.flags & CAM_DIR_MASK) != CAM_DIR_NONE)
894	    && (ccb->csio.data_ptr != NULL)) {
895		bzero(&mapinfo, sizeof(mapinfo));
896
897		/*
898		 * cam_periph_mapmem calls into proc and vm functions that can
899		 * sleep as well as trigger I/O, so we can't hold the lock.
900		 * Dropping it here is reasonably safe.
901		 */
902		cam_periph_unlock(periph);
903		error = cam_periph_mapmem(ccb, &mapinfo);
904		cam_periph_lock(periph);
905		if (error)
906			return (error);
907		need_unmap = 1;
908	}
909
910	error = cam_periph_runccb(ccb,
911				  sgerror,
912				  CAM_RETRY_SELTO,
913				  SF_RETRY_UA,
914				  softc->device_stats);
915
916	if (need_unmap)
917		cam_periph_unmapmem(ccb, &mapinfo);
918
919	return (error);
920}
921
922static int
923sgsendrdwr(struct cam_periph *periph, union ccb *ccb)
924{
925	struct sg_softc *softc;
926
927	softc = periph->softc;
928	devstat_start_transaction(softc->device_stats, NULL);
929	xpt_action(ccb);
930	return (0);
931}
932
933static int
934sgerror(union ccb *ccb, uint32_t cam_flags, uint32_t sense_flags)
935{
936	struct cam_periph *periph;
937	struct sg_softc *softc;
938
939	periph = xpt_path_periph(ccb->ccb_h.path);
940	softc = (struct sg_softc *)periph->softc;
941
942	return (cam_periph_error(ccb, cam_flags, sense_flags,
943				 &softc->saved_ccb));
944}
945
946static void
947sg_scsiio_status(struct ccb_scsiio *csio, u_short *hoststat, u_short *drvstat)
948{
949	int status;
950
951	status = csio->ccb_h.status;
952
953	switch (status & CAM_STATUS_MASK) {
954	case CAM_REQ_CMP:
955		*hoststat = DID_OK;
956		*drvstat = 0;
957		break;
958	case CAM_REQ_CMP_ERR:
959		*hoststat = DID_ERROR;
960		*drvstat = 0;
961		break;
962	case CAM_REQ_ABORTED:
963		*hoststat = DID_ABORT;
964		*drvstat = 0;
965		break;
966	case CAM_REQ_INVALID:
967		*hoststat = DID_ERROR;
968		*drvstat = DRIVER_INVALID;
969		break;
970	case CAM_DEV_NOT_THERE:
971		*hoststat = DID_BAD_TARGET;
972		*drvstat = 0;
973	case CAM_SEL_TIMEOUT:
974		*hoststat = DID_NO_CONNECT;
975		*drvstat = 0;
976		break;
977	case CAM_CMD_TIMEOUT:
978		*hoststat = DID_TIME_OUT;
979		*drvstat = 0;
980		break;
981	case CAM_SCSI_STATUS_ERROR:
982		*hoststat = DID_ERROR;
983		*drvstat = 0;
984	case CAM_SCSI_BUS_RESET:
985		*hoststat = DID_RESET;
986		*drvstat = 0;
987		break;
988	case CAM_UNCOR_PARITY:
989		*hoststat = DID_PARITY;
990		*drvstat = 0;
991		break;
992	case CAM_SCSI_BUSY:
993		*hoststat = DID_BUS_BUSY;
994		*drvstat = 0;
995	default:
996		*hoststat = DID_ERROR;
997		*drvstat = DRIVER_ERROR;
998	}
999
1000	if (status & CAM_AUTOSNS_VALID)
1001		*drvstat = DRIVER_SENSE;
1002}
1003
1004static int
1005scsi_group_len(u_char cmd)
1006{
1007	int len[] = {6, 10, 10, 12, 12, 12, 10, 10};
1008	int group;
1009
1010	group = (cmd >> 5) & 0x7;
1011	return (len[group]);
1012}
1013
1014