xref: /freebsd-13-stable/sys/cam/scsi/scsi_sg.c (revision 3bc80996974a61a4223eae4c1ccd47b6ee32a48a)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2007 Scott Long
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions, and the following disclaimer,
12  *    without modification, immediately at the beginning of the file.
13  * 2. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
20  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 /*
30  * scsi_sg peripheral driver.  This driver is meant to implement the Linux
31  * SG passthrough interface for SCSI.
32  */
33 
34 #include <sys/cdefs.h>
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 typedef enum {
62 	SG_FLAG_LOCKED		= 0x01,
63 	SG_FLAG_INVALID		= 0x02
64 } sg_flags;
65 
66 typedef enum {
67 	SG_STATE_NORMAL
68 } sg_state;
69 
70 typedef enum {
71 	SG_RDWR_FREE,
72 	SG_RDWR_INPROG,
73 	SG_RDWR_DONE
74 } sg_rdwr_state;
75 
76 typedef enum {
77 	SG_CCB_RDWR_IO
78 } sg_ccb_types;
79 
80 #define ccb_type	ppriv_field0
81 #define ccb_rdwr	ppriv_ptr1
82 
83 struct sg_rdwr {
84 	TAILQ_ENTRY(sg_rdwr)	rdwr_link;
85 	int			tag;
86 	int			state;
87 	int			buf_len;
88 	char			*buf;
89 	union ccb		*ccb;
90 	union {
91 		struct sg_header hdr;
92 		struct sg_io_hdr io_hdr;
93 	} hdr;
94 };
95 
96 struct sg_softc {
97 	sg_state		state;
98 	sg_flags		flags;
99 	int			open_count;
100 	u_int			maxio;
101 	struct devstat		*device_stats;
102 	TAILQ_HEAD(, sg_rdwr)	rdwr_done;
103 	struct cdev		*dev;
104 	int			sg_timeout;
105 	int			sg_user_timeout;
106 	uint8_t			pd_type;
107 	union ccb		saved_ccb;
108 };
109 
110 static d_open_t		sgopen;
111 static d_close_t	sgclose;
112 static d_ioctl_t	sgioctl;
113 static d_write_t	sgwrite;
114 static d_read_t		sgread;
115 
116 static periph_init_t	sginit;
117 static periph_ctor_t	sgregister;
118 static periph_oninv_t	sgoninvalidate;
119 static periph_dtor_t	sgcleanup;
120 static void		sgasync(void *callback_arg, uint32_t code,
121 				struct cam_path *path, void *arg);
122 static void		sgdone(struct cam_periph *periph, union ccb *done_ccb);
123 static int		sgsendccb(struct cam_periph *periph, union ccb *ccb);
124 static int		sgsendrdwr(struct cam_periph *periph, union ccb *ccb);
125 static int		sgerror(union ccb *ccb, uint32_t cam_flags,
126 				uint32_t sense_flags);
127 static void		sg_scsiio_status(struct ccb_scsiio *csio,
128 					 u_short *hoststat, u_short *drvstat);
129 
130 static int		scsi_group_len(u_char cmd);
131 
132 static struct periph_driver sgdriver =
133 {
134 	sginit, "sg",
135 	TAILQ_HEAD_INITIALIZER(sgdriver.units), /* gen */ 0
136 };
137 PERIPHDRIVER_DECLARE(sg, sgdriver);
138 
139 static struct cdevsw sg_cdevsw = {
140 	.d_version =	D_VERSION,
141 	.d_flags =	D_TRACKCLOSE,
142 	.d_open =	sgopen,
143 	.d_close =	sgclose,
144 	.d_ioctl =	sgioctl,
145 	.d_write =	sgwrite,
146 	.d_read =	sgread,
147 	.d_name =	"sg",
148 };
149 
150 static int sg_version = 30125;
151 
152 static void
sginit(void)153 sginit(void)
154 {
155 	cam_status status;
156 
157 	/*
158 	 * Install a global async callback.  This callback will receive aync
159 	 * callbacks like "new device found".
160 	 */
161 	status = xpt_register_async(AC_FOUND_DEVICE, sgasync, NULL, NULL);
162 
163 	if (status != CAM_REQ_CMP) {
164 		printf("sg: Failed to attach master async callbac "
165 			"due to status 0x%x!\n", status);
166 	}
167 }
168 
169 static void
sgdevgonecb(void * arg)170 sgdevgonecb(void *arg)
171 {
172 	struct cam_periph *periph;
173 	struct sg_softc *softc;
174 	struct mtx *mtx;
175 	int i;
176 
177 	periph = (struct cam_periph *)arg;
178 	mtx = cam_periph_mtx(periph);
179 	mtx_lock(mtx);
180 
181 	softc = (struct sg_softc *)periph->softc;
182 	KASSERT(softc->open_count >= 0, ("Negative open count %d",
183 		softc->open_count));
184 
185 	/*
186 	 * When we get this callback, we will get no more close calls from
187 	 * devfs.  So if we have any dangling opens, we need to release the
188 	 * reference held for that particular context.
189 	 */
190 	for (i = 0; i < softc->open_count; i++)
191 		cam_periph_release_locked(periph);
192 
193 	softc->open_count = 0;
194 
195 	/*
196 	 * Release the reference held for the device node, it is gone now.
197 	 */
198 	cam_periph_release_locked(periph);
199 
200 	/*
201 	 * We reference the lock directly here, instead of using
202 	 * cam_periph_unlock().  The reason is that the final call to
203 	 * cam_periph_release_locked() above could result in the periph
204 	 * getting freed.  If that is the case, dereferencing the periph
205 	 * with a cam_periph_unlock() call would cause a page fault.
206 	 */
207 	mtx_unlock(mtx);
208 }
209 
210 static void
sgoninvalidate(struct cam_periph * periph)211 sgoninvalidate(struct cam_periph *periph)
212 {
213 	struct sg_softc *softc;
214 
215 	softc = (struct sg_softc *)periph->softc;
216 
217 	/*
218 	 * Deregister any async callbacks.
219 	 */
220 	xpt_register_async(0, sgasync, periph, periph->path);
221 
222 	softc->flags |= SG_FLAG_INVALID;
223 
224 	/*
225 	 * Tell devfs this device has gone away, and ask for a callback
226 	 * when it has cleaned up its state.
227 	 */
228 	destroy_dev_sched_cb(softc->dev, sgdevgonecb, periph);
229 
230 	/*
231 	 * XXX Return all queued I/O with ENXIO.
232 	 * XXX Handle any transactions queued to the card
233 	 *     with XPT_ABORT_CCB.
234 	 */
235 
236 }
237 
238 static void
sgcleanup(struct cam_periph * periph)239 sgcleanup(struct cam_periph *periph)
240 {
241 	struct sg_softc *softc;
242 
243 	softc = (struct sg_softc *)periph->softc;
244 
245 	devstat_remove_entry(softc->device_stats);
246 
247 	free(softc, M_DEVBUF);
248 }
249 
250 static void
sgasync(void * callback_arg,uint32_t code,struct cam_path * path,void * arg)251 sgasync(void *callback_arg, uint32_t code, struct cam_path *path, void *arg)
252 {
253 	struct cam_periph *periph;
254 
255 	periph = (struct cam_periph *)callback_arg;
256 
257 	switch (code) {
258 	case AC_FOUND_DEVICE:
259 	{
260 		struct ccb_getdev *cgd;
261 		cam_status status;
262 
263 		cgd = (struct ccb_getdev *)arg;
264 		if (cgd == NULL)
265 			break;
266 
267 		if (cgd->protocol != PROTO_SCSI)
268 			break;
269 
270 		/*
271 		 * Allocate a peripheral instance for this device and
272 		 * start the probe process.
273 		 */
274 		status = cam_periph_alloc(sgregister, sgoninvalidate,
275 					  sgcleanup, NULL, "sg",
276 					  CAM_PERIPH_BIO, path,
277 					  sgasync, AC_FOUND_DEVICE, cgd);
278 		if ((status != CAM_REQ_CMP) && (status != CAM_REQ_INPROG)) {
279 			const struct cam_status_entry *entry;
280 
281 			entry = cam_fetch_status_entry(status);
282 			printf("sgasync: Unable to attach new device "
283 				"due to status %#x: %s\n", status, entry ?
284 				entry->status_text : "Unknown");
285 		}
286 		break;
287 	}
288 	default:
289 		cam_periph_async(periph, code, path, arg);
290 		break;
291 	}
292 }
293 
294 static cam_status
sgregister(struct cam_periph * periph,void * arg)295 sgregister(struct cam_periph *periph, void *arg)
296 {
297 	struct sg_softc *softc;
298 	struct ccb_getdev *cgd;
299 	struct ccb_pathinq cpi;
300 	struct make_dev_args args;
301 	int no_tags, error;
302 
303 	cgd = (struct ccb_getdev *)arg;
304 	if (cgd == NULL) {
305 		printf("sgregister: no getdev CCB, can't register device\n");
306 		return (CAM_REQ_CMP_ERR);
307 	}
308 
309 	softc = malloc(sizeof(*softc), M_DEVBUF, M_ZERO | M_NOWAIT);
310 	if (softc == NULL) {
311 		printf("sgregister: Unable to allocate softc\n");
312 		return (CAM_REQ_CMP_ERR);
313 	}
314 
315 	softc->state = SG_STATE_NORMAL;
316 	softc->pd_type = SID_TYPE(&cgd->inq_data);
317 	softc->sg_timeout = SG_DEFAULT_TIMEOUT / SG_DEFAULT_HZ * hz;
318 	softc->sg_user_timeout = SG_DEFAULT_TIMEOUT;
319 	TAILQ_INIT(&softc->rdwr_done);
320 	periph->softc = softc;
321 
322 	xpt_path_inq(&cpi, periph->path);
323 
324 	if (cpi.maxio == 0)
325 		softc->maxio = DFLTPHYS;	/* traditional default */
326 	else if (cpi.maxio > maxphys)
327 		softc->maxio = maxphys;		/* for safety */
328 	else
329 		softc->maxio = cpi.maxio;	/* real value */
330 
331 	/*
332 	 * We pass in 0 for all blocksize, since we don't know what the
333 	 * blocksize of the device is, if it even has a blocksize.
334 	 */
335 	cam_periph_unlock(periph);
336 	no_tags = (cgd->inq_data.flags & SID_CmdQue) == 0;
337 	softc->device_stats = devstat_new_entry("sg",
338 			periph->unit_number, 0,
339 			DEVSTAT_NO_BLOCKSIZE
340 			| (no_tags ? DEVSTAT_NO_ORDERED_TAGS : 0),
341 			softc->pd_type |
342 			XPORT_DEVSTAT_TYPE(cpi.transport) |
343 			DEVSTAT_TYPE_PASS,
344 			DEVSTAT_PRIORITY_PASS);
345 
346 	/*
347 	 * Acquire a reference to the periph before we create the devfs
348 	 * instance for it.  We'll release this reference once the devfs
349 	 * instance has been freed.
350 	 */
351 	if (cam_periph_acquire(periph) != 0) {
352 		xpt_print(periph->path, "%s: lost periph during "
353 			  "registration!\n", __func__);
354 		cam_periph_lock(periph);
355 		return (CAM_REQ_CMP_ERR);
356 	}
357 
358 	/* Register the device */
359 	make_dev_args_init(&args);
360 	args.mda_devsw = &sg_cdevsw;
361 	args.mda_unit = periph->unit_number;
362 	args.mda_uid = UID_ROOT;
363 	args.mda_gid = GID_OPERATOR;
364 	args.mda_mode = 0600;
365 	args.mda_si_drv1 = periph;
366 	error = make_dev_s(&args, &softc->dev, "%s%d",
367 	    periph->periph_name, periph->unit_number);
368 	if (error != 0) {
369 		cam_periph_lock(periph);
370 		cam_periph_release_locked(periph);
371 		return (CAM_REQ_CMP_ERR);
372 	}
373 	if (periph->unit_number < 26) {
374 		(void)make_dev_alias(softc->dev, "sg%c",
375 		    periph->unit_number + 'a');
376 	} else {
377 		(void)make_dev_alias(softc->dev, "sg%c%c",
378 		    ((periph->unit_number / 26) - 1) + 'a',
379 		    (periph->unit_number % 26) + 'a');
380 	}
381 	cam_periph_lock(periph);
382 
383 	/*
384 	 * Add as async callback so that we get
385 	 * notified if this device goes away.
386 	 */
387 	xpt_register_async(AC_LOST_DEVICE, sgasync, periph, periph->path);
388 
389 	if (bootverbose)
390 		xpt_announce_periph(periph, NULL);
391 
392 	return (CAM_REQ_CMP);
393 }
394 
395 static void
sgdone(struct cam_periph * periph,union ccb * done_ccb)396 sgdone(struct cam_periph *periph, union ccb *done_ccb)
397 {
398 	struct sg_softc *softc;
399 	struct ccb_scsiio *csio;
400 
401 	softc = (struct sg_softc *)periph->softc;
402 	csio = &done_ccb->csio;
403 	switch (csio->ccb_h.ccb_type) {
404 	case SG_CCB_RDWR_IO:
405 	{
406 		struct sg_rdwr *rdwr;
407 		int state;
408 
409 		devstat_end_transaction(softc->device_stats,
410 					csio->dxfer_len,
411 					csio->tag_action & 0xf,
412 					((csio->ccb_h.flags & CAM_DIR_MASK) ==
413 					CAM_DIR_NONE) ? DEVSTAT_NO_DATA :
414 					(csio->ccb_h.flags & CAM_DIR_OUT) ?
415 					DEVSTAT_WRITE : DEVSTAT_READ,
416 					NULL, NULL);
417 
418 		rdwr = done_ccb->ccb_h.ccb_rdwr;
419 		state = rdwr->state;
420 		rdwr->state = SG_RDWR_DONE;
421 		wakeup(rdwr);
422 		break;
423 	}
424 	default:
425 		panic("unknown sg CCB type");
426 	}
427 }
428 
429 static int
sgopen(struct cdev * dev,int flags,int fmt,struct thread * td)430 sgopen(struct cdev *dev, int flags, int fmt, struct thread *td)
431 {
432 	struct cam_periph *periph;
433 	struct sg_softc *softc;
434 	int error = 0;
435 
436 	periph = (struct cam_periph *)dev->si_drv1;
437 	if (cam_periph_acquire(periph) != 0)
438 		return (ENXIO);
439 
440 	/*
441 	 * Don't allow access when we're running at a high securelevel.
442 	 */
443 	error = securelevel_gt(td->td_ucred, 1);
444 	if (error) {
445 		cam_periph_release(periph);
446 		return (error);
447 	}
448 
449 	cam_periph_lock(periph);
450 
451 	softc = (struct sg_softc *)periph->softc;
452 	if (softc->flags & SG_FLAG_INVALID) {
453 		cam_periph_release_locked(periph);
454 		cam_periph_unlock(periph);
455 		return (ENXIO);
456 	}
457 
458 	softc->open_count++;
459 
460 	cam_periph_unlock(periph);
461 
462 	return (error);
463 }
464 
465 static int
sgclose(struct cdev * dev,int flag,int fmt,struct thread * td)466 sgclose(struct cdev *dev, int flag, int fmt, struct thread *td)
467 {
468 	struct cam_periph *periph;
469 	struct sg_softc   *softc;
470 	struct mtx *mtx;
471 
472 	periph = (struct cam_periph *)dev->si_drv1;
473 	mtx = cam_periph_mtx(periph);
474 	mtx_lock(mtx);
475 
476 	softc = periph->softc;
477 	softc->open_count--;
478 
479 	cam_periph_release_locked(periph);
480 
481 	/*
482 	 * We reference the lock directly here, instead of using
483 	 * cam_periph_unlock().  The reason is that the call to
484 	 * cam_periph_release_locked() above could result in the periph
485 	 * getting freed.  If that is the case, dereferencing the periph
486 	 * with a cam_periph_unlock() call would cause a page fault.
487 	 *
488 	 * cam_periph_release() avoids this problem using the same method,
489 	 * but we're manually acquiring and dropping the lock here to
490 	 * protect the open count and avoid another lock acquisition and
491 	 * release.
492 	 */
493 	mtx_unlock(mtx);
494 
495 	return (0);
496 }
497 
498 static int
sgioctl(struct cdev * dev,u_long cmd,caddr_t arg,int flag,struct thread * td)499 sgioctl(struct cdev *dev, u_long cmd, caddr_t arg, int flag, struct thread *td)
500 {
501 	union ccb *ccb;
502 	struct ccb_scsiio *csio;
503 	struct cam_periph *periph;
504 	struct sg_softc *softc;
505 	struct sg_io_hdr *req;
506 	int dir, error;
507 
508 	periph = (struct cam_periph *)dev->si_drv1;
509 	cam_periph_lock(periph);
510 
511 	softc = (struct sg_softc *)periph->softc;
512 	error = 0;
513 
514 	switch (cmd) {
515 	case SG_GET_VERSION_NUM:
516 	{
517 		int *version = (int *)arg;
518 
519 		*version = sg_version;
520 		break;
521 	}
522 	case SG_SET_TIMEOUT:
523 	{
524 		u_int user_timeout = *(u_int *)arg;
525 
526 		softc->sg_user_timeout = user_timeout;
527 		softc->sg_timeout = user_timeout / SG_DEFAULT_HZ * hz;
528 		break;
529 	}
530 	case SG_GET_TIMEOUT:
531 		/*
532 		 * The value is returned directly to the syscall.
533 		 */
534 		td->td_retval[0] = softc->sg_user_timeout;
535 		error = 0;
536 		break;
537 	case SG_IO:
538 		req = (struct sg_io_hdr *)arg;
539 
540 		if (req->cmd_len > IOCDBLEN) {
541 			error = EINVAL;
542 			break;
543 		}
544 
545 		if (req->iovec_count != 0) {
546 			error = EOPNOTSUPP;
547 			break;
548 		}
549 
550 		ccb = cam_periph_getccb(periph, CAM_PRIORITY_NORMAL);
551 		csio = &ccb->csio;
552 
553 		error = copyin(req->cmdp, &csio->cdb_io.cdb_bytes,
554 		    req->cmd_len);
555 		if (error) {
556 			xpt_release_ccb(ccb);
557 			break;
558 		}
559 
560 		switch(req->dxfer_direction) {
561 		case SG_DXFER_TO_DEV:
562 			dir = CAM_DIR_OUT;
563 			break;
564 		case SG_DXFER_FROM_DEV:
565 			dir = CAM_DIR_IN;
566 			break;
567 		case SG_DXFER_TO_FROM_DEV:
568 			dir = CAM_DIR_BOTH;
569 			break;
570 		case SG_DXFER_NONE:
571 		default:
572 			dir = CAM_DIR_NONE;
573 			break;
574 		}
575 
576 		cam_fill_csio(csio,
577 			      /*retries*/1,
578 			      /*cbfcnp*/NULL,
579 			      dir|CAM_DEV_QFRZDIS,
580 			      MSG_SIMPLE_Q_TAG,
581 			      req->dxferp,
582 			      req->dxfer_len,
583 			      req->mx_sb_len,
584 			      req->cmd_len,
585 			      req->timeout);
586 
587 		error = sgsendccb(periph, ccb);
588 		if (error) {
589 			req->host_status = DID_ERROR;
590 			req->driver_status = DRIVER_INVALID;
591 			xpt_release_ccb(ccb);
592 			break;
593 		}
594 
595 		req->status = csio->scsi_status;
596 		req->masked_status = (csio->scsi_status >> 1) & 0x7f;
597 		sg_scsiio_status(csio, &req->host_status, &req->driver_status);
598 		req->resid = csio->resid;
599 		req->duration = csio->ccb_h.timeout;
600 		req->info = 0;
601 
602 		if ((csio->ccb_h.status & CAM_AUTOSNS_VALID)
603 		    && (req->sbp != NULL)) {
604 			req->sb_len_wr = req->mx_sb_len - csio->sense_resid;
605 			error = copyout(&csio->sense_data, req->sbp,
606 					req->sb_len_wr);
607 		}
608 
609 		xpt_release_ccb(ccb);
610 		break;
611 
612 	case SG_GET_RESERVED_SIZE:
613 	{
614 		int *size = (int *)arg;
615 		*size = DFLTPHYS;
616 		break;
617 	}
618 
619 	case SG_GET_SCSI_ID:
620 	{
621 		struct sg_scsi_id *id = (struct sg_scsi_id *)arg;
622 
623 		id->host_no = cam_sim_path(xpt_path_sim(periph->path));
624 		id->channel = xpt_path_path_id(periph->path);
625 		id->scsi_id = xpt_path_target_id(periph->path);
626 		id->lun = xpt_path_lun_id(periph->path);
627 		id->scsi_type = softc->pd_type;
628 		id->h_cmd_per_lun = 1;
629 		id->d_queue_depth = 1;
630 		id->unused[0] = 0;
631 		id->unused[1] = 0;
632 		break;
633 	}
634 
635 	case SG_GET_SG_TABLESIZE:
636 	{
637 		int *size = (int *)arg;
638 		*size = 0;
639 		break;
640 	}
641 
642 	case SG_EMULATED_HOST:
643 	case SG_SET_TRANSFORM:
644 	case SG_GET_TRANSFORM:
645 	case SG_GET_NUM_WAITING:
646 	case SG_SCSI_RESET:
647 	case SG_GET_REQUEST_TABLE:
648 	case SG_SET_KEEP_ORPHAN:
649 	case SG_GET_KEEP_ORPHAN:
650 	case SG_GET_ACCESS_COUNT:
651 	case SG_SET_FORCE_LOW_DMA:
652 	case SG_GET_LOW_DMA:
653 	case SG_SET_FORCE_PACK_ID:
654 	case SG_GET_PACK_ID:
655 	case SG_SET_RESERVED_SIZE:
656 	case SG_GET_COMMAND_Q:
657 	case SG_SET_COMMAND_Q:
658 	case SG_SET_DEBUG:
659 	case SG_NEXT_CMD_LEN:
660 	default:
661 #ifdef CAMDEBUG
662 		printf("sgioctl: rejecting cmd 0x%lx\n", cmd);
663 #endif
664 		error = ENODEV;
665 		break;
666 	}
667 
668 	cam_periph_unlock(periph);
669 	return (error);
670 }
671 
672 static int
sgwrite(struct cdev * dev,struct uio * uio,int ioflag)673 sgwrite(struct cdev *dev, struct uio *uio, int ioflag)
674 {
675 	union ccb *ccb;
676 	struct cam_periph *periph;
677 	struct ccb_scsiio *csio;
678 	struct sg_softc *sc;
679 	struct sg_header *hdr;
680 	struct sg_rdwr *rdwr;
681 	u_char cdb_cmd;
682 	char *buf;
683 	int error = 0, cdb_len, buf_len, dir;
684 
685 	periph = dev->si_drv1;
686 	rdwr = malloc(sizeof(*rdwr), M_DEVBUF, M_WAITOK | M_ZERO);
687 	hdr = &rdwr->hdr.hdr;
688 
689 	/* Copy in the header block and sanity check it */
690 	if (uio->uio_resid < sizeof(*hdr)) {
691 		error = EINVAL;
692 		goto out_hdr;
693 	}
694 	error = uiomove(hdr, sizeof(*hdr), uio);
695 	if (error)
696 		goto out_hdr;
697 
698 	/* XXX: We don't support SG 3.x read/write API. */
699 	if (hdr->reply_len < 0) {
700 		error = ENODEV;
701 		goto out_hdr;
702 	}
703 
704 	ccb = xpt_alloc_ccb();
705 	if (ccb == NULL) {
706 		error = ENOMEM;
707 		goto out_hdr;
708 	}
709 	csio = &ccb->csio;
710 
711 	/*
712 	 * Copy in the CDB block.  The designers of the interface didn't
713 	 * bother to provide a size for this in the header, so we have to
714 	 * figure it out ourselves.
715 	 */
716 	if (uio->uio_resid < 1)
717 		goto out_ccb;
718 	error = uiomove(&cdb_cmd, 1, uio);
719 	if (error)
720 		goto out_ccb;
721 	if (hdr->twelve_byte)
722 		cdb_len = 12;
723 	else
724 		cdb_len = scsi_group_len(cdb_cmd);
725 	/*
726 	 * We've already read the first byte of the CDB and advanced the uio
727 	 * pointer.  Just read the rest.
728 	 */
729 	csio->cdb_io.cdb_bytes[0] = cdb_cmd;
730 	error = uiomove(&csio->cdb_io.cdb_bytes[1], cdb_len - 1, uio);
731 	if (error)
732 		goto out_ccb;
733 
734 	/*
735 	 * Now set up the data block.  Again, the designers didn't bother
736 	 * to make this reliable.
737 	 */
738 	buf_len = uio->uio_resid;
739 	if (buf_len != 0) {
740 		buf = malloc(buf_len, M_DEVBUF, M_WAITOK | M_ZERO);
741 		error = uiomove(buf, buf_len, uio);
742 		if (error)
743 			goto out_buf;
744 		dir = CAM_DIR_OUT;
745 	} else if (hdr->reply_len != 0) {
746 		buf = malloc(hdr->reply_len, M_DEVBUF, M_WAITOK | M_ZERO);
747 		buf_len = hdr->reply_len;
748 		dir = CAM_DIR_IN;
749 	} else {
750 		buf = NULL;
751 		buf_len = 0;
752 		dir = CAM_DIR_NONE;
753 	}
754 
755 	cam_periph_lock(periph);
756 	sc = periph->softc;
757 	xpt_setup_ccb(&ccb->ccb_h, periph->path, CAM_PRIORITY_NORMAL);
758 	cam_fill_csio(csio,
759 		      /*retries*/1,
760 		      sgdone,
761 		      dir|CAM_DEV_QFRZDIS,
762 		      MSG_SIMPLE_Q_TAG,
763 		      buf,
764 		      buf_len,
765 		      SG_MAX_SENSE,
766 		      cdb_len,
767 		      sc->sg_timeout);
768 
769 	/*
770 	 * Send off the command and hope that it works. This path does not
771 	 * go through sgstart because the I/O is supposed to be asynchronous.
772 	 */
773 	rdwr->buf = buf;
774 	rdwr->buf_len = buf_len;
775 	rdwr->tag = hdr->pack_id;
776 	rdwr->ccb = ccb;
777 	rdwr->state = SG_RDWR_INPROG;
778 	ccb->ccb_h.ccb_rdwr = rdwr;
779 	ccb->ccb_h.ccb_type = SG_CCB_RDWR_IO;
780 	TAILQ_INSERT_TAIL(&sc->rdwr_done, rdwr, rdwr_link);
781 	error = sgsendrdwr(periph, ccb);
782 	cam_periph_unlock(periph);
783 	return (error);
784 
785 out_buf:
786 	free(buf, M_DEVBUF);
787 out_ccb:
788 	xpt_free_ccb(ccb);
789 out_hdr:
790 	free(rdwr, M_DEVBUF);
791 	return (error);
792 }
793 
794 static int
sgread(struct cdev * dev,struct uio * uio,int ioflag)795 sgread(struct cdev *dev, struct uio *uio, int ioflag)
796 {
797 	struct ccb_scsiio *csio;
798 	struct cam_periph *periph;
799 	struct sg_softc *sc;
800 	struct sg_header *hdr;
801 	struct sg_rdwr *rdwr;
802 	u_short hstat, dstat;
803 	int error, pack_len, reply_len, pack_id;
804 
805 	periph = dev->si_drv1;
806 
807 	/* XXX The pack len field needs to be updated and written out instead
808 	 * of discarded.  Not sure how to do that.
809 	 */
810 	uio->uio_rw = UIO_WRITE;
811 	if ((error = uiomove(&pack_len, 4, uio)) != 0)
812 		return (error);
813 	if ((error = uiomove(&reply_len, 4, uio)) != 0)
814 		return (error);
815 	if ((error = uiomove(&pack_id, 4, uio)) != 0)
816 		return (error);
817 	uio->uio_rw = UIO_READ;
818 
819 	cam_periph_lock(periph);
820 	sc = periph->softc;
821 search:
822 	TAILQ_FOREACH(rdwr, &sc->rdwr_done, rdwr_link) {
823 		if (rdwr->tag == pack_id)
824 			break;
825 	}
826 	if ((rdwr == NULL) || (rdwr->state != SG_RDWR_DONE)) {
827 		if (cam_periph_sleep(periph, rdwr, PCATCH, "sgread", 0) == ERESTART)
828 			return (EAGAIN);
829 		goto search;
830 	}
831 	TAILQ_REMOVE(&sc->rdwr_done, rdwr, rdwr_link);
832 	cam_periph_unlock(periph);
833 
834 	hdr = &rdwr->hdr.hdr;
835 	csio = &rdwr->ccb->csio;
836 	sg_scsiio_status(csio, &hstat, &dstat);
837 	hdr->host_status = hstat;
838 	hdr->driver_status = dstat;
839 	hdr->target_status = csio->scsi_status >> 1;
840 
841 	switch (hstat) {
842 	case DID_OK:
843 	case DID_PASSTHROUGH:
844 	case DID_SOFT_ERROR:
845 		hdr->result = 0;
846 		break;
847 	case DID_NO_CONNECT:
848 	case DID_BUS_BUSY:
849 	case DID_TIME_OUT:
850 		hdr->result = EBUSY;
851 		break;
852 	case DID_BAD_TARGET:
853 	case DID_ABORT:
854 	case DID_PARITY:
855 	case DID_RESET:
856 	case DID_BAD_INTR:
857 	case DID_ERROR:
858 	default:
859 		hdr->result = EIO;
860 		break;
861 	}
862 
863 	if (dstat == DRIVER_SENSE) {
864 		bcopy(&csio->sense_data, hdr->sense_buffer,
865 		      min(csio->sense_len, SG_MAX_SENSE));
866 #ifdef CAMDEBUG
867 		scsi_sense_print(csio);
868 #endif
869 	}
870 
871 	error = uiomove(&hdr->result, sizeof(*hdr) -
872 			offsetof(struct sg_header, result), uio);
873 	if ((error == 0) && (hdr->result == 0))
874 		error = uiomove(rdwr->buf, rdwr->buf_len, uio);
875 
876 	cam_periph_lock(periph);
877 	xpt_free_ccb(rdwr->ccb);
878 	cam_periph_unlock(periph);
879 	free(rdwr->buf, M_DEVBUF);
880 	free(rdwr, M_DEVBUF);
881 	return (error);
882 }
883 
884 static int
sgsendccb(struct cam_periph * periph,union ccb * ccb)885 sgsendccb(struct cam_periph *periph, union ccb *ccb)
886 {
887 	struct sg_softc *softc;
888 	struct cam_periph_map_info mapinfo;
889 	int error;
890 
891 	softc = periph->softc;
892 	bzero(&mapinfo, sizeof(mapinfo));
893 
894 	/*
895 	 * cam_periph_mapmem calls into proc and vm functions that can
896 	 * sleep as well as trigger I/O, so we can't hold the lock.
897 	 * Dropping it here is reasonably safe.
898 	 * The only CCB opcode that is possible here is XPT_SCSI_IO, no
899 	 * need for additional checks.
900 	 */
901 	cam_periph_unlock(periph);
902 	error = cam_periph_mapmem(ccb, &mapinfo, softc->maxio);
903 	cam_periph_lock(periph);
904 	if (error)
905 		return (error);
906 
907 	error = cam_periph_runccb(ccb,
908 				  sgerror,
909 				  CAM_RETRY_SELTO,
910 				  SF_RETRY_UA,
911 				  softc->device_stats);
912 
913 	cam_periph_unlock(periph);
914 	cam_periph_unmapmem(ccb, &mapinfo);
915 	cam_periph_lock(periph);
916 
917 	return (error);
918 }
919 
920 static int
sgsendrdwr(struct cam_periph * periph,union ccb * ccb)921 sgsendrdwr(struct cam_periph *periph, union ccb *ccb)
922 {
923 	struct sg_softc *softc;
924 
925 	softc = periph->softc;
926 	devstat_start_transaction(softc->device_stats, NULL);
927 	xpt_action(ccb);
928 	return (0);
929 }
930 
931 static int
sgerror(union ccb * ccb,uint32_t cam_flags,uint32_t sense_flags)932 sgerror(union ccb *ccb, uint32_t cam_flags, uint32_t sense_flags)
933 {
934 	struct cam_periph *periph;
935 	struct sg_softc *softc;
936 
937 	periph = xpt_path_periph(ccb->ccb_h.path);
938 	softc = (struct sg_softc *)periph->softc;
939 
940 	return (cam_periph_error(ccb, cam_flags, sense_flags));
941 }
942 
943 static void
sg_scsiio_status(struct ccb_scsiio * csio,u_short * hoststat,u_short * drvstat)944 sg_scsiio_status(struct ccb_scsiio *csio, u_short *hoststat, u_short *drvstat)
945 {
946 	int status;
947 
948 	status = csio->ccb_h.status;
949 
950 	switch (status & CAM_STATUS_MASK) {
951 	case CAM_REQ_CMP:
952 		*hoststat = DID_OK;
953 		*drvstat = 0;
954 		break;
955 	case CAM_REQ_CMP_ERR:
956 		*hoststat = DID_ERROR;
957 		*drvstat = 0;
958 		break;
959 	case CAM_REQ_ABORTED:
960 		*hoststat = DID_ABORT;
961 		*drvstat = 0;
962 		break;
963 	case CAM_REQ_INVALID:
964 		*hoststat = DID_ERROR;
965 		*drvstat = DRIVER_INVALID;
966 		break;
967 	case CAM_DEV_NOT_THERE:
968 		*hoststat = DID_BAD_TARGET;
969 		*drvstat = 0;
970 		break;
971 	case CAM_SEL_TIMEOUT:
972 		*hoststat = DID_NO_CONNECT;
973 		*drvstat = 0;
974 		break;
975 	case CAM_CMD_TIMEOUT:
976 		*hoststat = DID_TIME_OUT;
977 		*drvstat = 0;
978 		break;
979 	case CAM_SCSI_STATUS_ERROR:
980 		*hoststat = DID_ERROR;
981 		*drvstat = 0;
982 		break;
983 	case CAM_SCSI_BUS_RESET:
984 		*hoststat = DID_RESET;
985 		*drvstat = 0;
986 		break;
987 	case CAM_UNCOR_PARITY:
988 		*hoststat = DID_PARITY;
989 		*drvstat = 0;
990 		break;
991 	case CAM_SCSI_BUSY:
992 		*hoststat = DID_BUS_BUSY;
993 		*drvstat = 0;
994 		break;
995 	default:
996 		*hoststat = DID_ERROR;
997 		*drvstat = DRIVER_ERROR;
998 	}
999 
1000 	if (status & CAM_AUTOSNS_VALID)
1001 		*drvstat = DRIVER_SENSE;
1002 }
1003 
1004 static int
scsi_group_len(u_char cmd)1005 scsi_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