1/*-
2 * Generic SCSI Target Kernel Mode Driver
3 *
4 * Copyright (c) 2002 Nate Lawson.
5 * Copyright (c) 1998, 1999, 2001, 2002 Justin T. Gibbs.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions, and the following disclaimer,
13 *    without modification, immediately at the beginning of the file.
14 * 2. The name of the author may not be used to endorse or promote products
15 *    derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
21 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD: releng/10.2/sys/cam/scsi/scsi_target.c 260387 2014-01-07 01:51:48Z scottl $");
32
33
34#include <sys/param.h>
35#include <sys/systm.h>
36#include <sys/kernel.h>
37#include <sys/conf.h>
38#include <sys/malloc.h>
39#include <sys/poll.h>
40#include <sys/vnode.h>
41#include <sys/lock.h>
42#include <sys/mutex.h>
43#include <sys/devicestat.h>
44#include <sys/proc.h>
45/* Includes to support callout */
46#include <sys/types.h>
47#include <sys/systm.h>
48
49#include <cam/cam.h>
50#include <cam/cam_ccb.h>
51#include <cam/cam_periph.h>
52#include <cam/cam_xpt_periph.h>
53#include <cam/cam_sim.h>
54#include <cam/scsi/scsi_targetio.h>
55
56
57/* Transaction information attached to each CCB sent by the user */
58struct targ_cmd_descr {
59	struct cam_periph_map_info  mapinfo;
60	TAILQ_ENTRY(targ_cmd_descr) tqe;
61	union ccb *user_ccb;
62	int	   priority;
63	int	   func_code;
64};
65
66/* Offset into the private CCB area for storing our descriptor */
67#define targ_descr	periph_priv.entries[1].ptr
68
69TAILQ_HEAD(descr_queue, targ_cmd_descr);
70
71typedef enum {
72	TARG_STATE_RESV		= 0x00, /* Invalid state */
73	TARG_STATE_OPENED	= 0x01, /* Device opened, softc initialized */
74	TARG_STATE_LUN_ENABLED	= 0x02  /* Device enabled for a path */
75} targ_state;
76
77/* Per-instance device software context */
78struct targ_softc {
79	/* CCBs (CTIOs, ATIOs, INOTs) pending on the controller */
80	struct ccb_queue	 pending_ccb_queue;
81
82	/* Command descriptors awaiting CTIO resources from the XPT */
83	struct descr_queue	 work_queue;
84
85	/* Command descriptors that have been aborted back to the user. */
86	struct descr_queue	 abort_queue;
87
88	/*
89	 * Queue of CCBs that have been copied out to userland, but our
90	 * userland daemon has not yet seen.
91	 */
92	struct ccb_queue	 user_ccb_queue;
93
94	struct cam_periph	*periph;
95	struct cam_path		*path;
96	targ_state		 state;
97	struct selinfo		 read_select;
98	struct devstat		 device_stats;
99};
100
101static d_open_t		targopen;
102static d_read_t		targread;
103static d_write_t	targwrite;
104static d_ioctl_t	targioctl;
105static d_poll_t		targpoll;
106static d_kqfilter_t	targkqfilter;
107static void		targreadfiltdetach(struct knote *kn);
108static int		targreadfilt(struct knote *kn, long hint);
109static struct filterops targread_filtops = {
110	.f_isfd = 1,
111	.f_detach = targreadfiltdetach,
112	.f_event = targreadfilt,
113};
114
115static struct cdevsw targ_cdevsw = {
116	.d_version =	D_VERSION,
117	.d_flags =	D_NEEDGIANT,
118	.d_open =	targopen,
119	.d_read =	targread,
120	.d_write =	targwrite,
121	.d_ioctl =	targioctl,
122	.d_poll =	targpoll,
123	.d_name =	"targ",
124	.d_kqfilter =	targkqfilter
125};
126
127static cam_status	targendislun(struct cam_path *path, int enable,
128				     int grp6_len, int grp7_len);
129static cam_status	targenable(struct targ_softc *softc,
130				   struct cam_path *path,
131				   int grp6_len, int grp7_len);
132static cam_status	targdisable(struct targ_softc *softc);
133static periph_ctor_t    targctor;
134static periph_dtor_t    targdtor;
135static periph_start_t   targstart;
136static int		targusermerge(struct targ_softc *softc,
137				      struct targ_cmd_descr *descr,
138				      union ccb *ccb);
139static int		targsendccb(struct targ_softc *softc, union ccb *ccb,
140				    struct targ_cmd_descr *descr);
141static void		targdone(struct cam_periph *periph,
142				 union  ccb *done_ccb);
143static int		targreturnccb(struct targ_softc *softc,
144				      union  ccb *ccb);
145static union ccb *	targgetccb(struct targ_softc *softc, xpt_opcode type,
146				   int priority);
147static void		targfreeccb(struct targ_softc *softc, union ccb *ccb);
148static struct targ_cmd_descr *
149			targgetdescr(struct targ_softc *softc);
150static periph_init_t	targinit;
151static void		targasync(void *callback_arg, u_int32_t code,
152				  struct cam_path *path, void *arg);
153static void		abort_all_pending(struct targ_softc *softc);
154static void		notify_user(struct targ_softc *softc);
155static int		targcamstatus(cam_status status);
156static size_t		targccblen(xpt_opcode func_code);
157
158static struct periph_driver targdriver =
159{
160	targinit, "targ",
161	TAILQ_HEAD_INITIALIZER(targdriver.units), /* generation */ 0
162};
163PERIPHDRIVER_DECLARE(targ, targdriver);
164
165static MALLOC_DEFINE(M_TARG, "TARG", "TARG data");
166
167/* Disable LUN if enabled and teardown softc */
168static void
169targcdevdtor(void *data)
170{
171	struct targ_softc *softc;
172	struct cam_periph *periph;
173
174	softc = data;
175	if (softc->periph == NULL) {
176		printf("%s: destroying non-enabled target\n", __func__);
177		free(softc, M_TARG);
178		return;
179	}
180
181	/*
182	 * Acquire a hold on the periph so that it doesn't go away before
183	 * we are ready at the end of the function.
184	 */
185	periph = softc->periph;
186	cam_periph_acquire(periph);
187	cam_periph_lock(periph);
188	(void)targdisable(softc);
189	if (softc->periph != NULL) {
190		cam_periph_invalidate(softc->periph);
191		softc->periph = NULL;
192	}
193	cam_periph_unlock(periph);
194	cam_periph_release(periph);
195	free(softc, M_TARG);
196}
197
198/*
199 * Create softc and initialize it.  There is no locking here because a
200 * periph doesn't get created until an ioctl is issued to do so, and
201 * that can't happen until this method returns.
202 */
203static int
204targopen(struct cdev *dev, int flags, int fmt, struct thread *td)
205{
206	struct targ_softc *softc;
207
208	/* Allocate its softc, initialize it */
209	softc = malloc(sizeof(*softc), M_TARG,
210	       M_WAITOK | M_ZERO);
211	softc->state = TARG_STATE_OPENED;
212	softc->periph = NULL;
213	softc->path = NULL;
214
215	TAILQ_INIT(&softc->pending_ccb_queue);
216	TAILQ_INIT(&softc->work_queue);
217	TAILQ_INIT(&softc->abort_queue);
218	TAILQ_INIT(&softc->user_ccb_queue);
219	knlist_init_mtx(&softc->read_select.si_note, NULL);
220
221	devfs_set_cdevpriv(softc, targcdevdtor);
222	return (0);
223}
224
225/* Enable/disable LUNs, set debugging level */
226static int
227targioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
228{
229	struct targ_softc *softc;
230	cam_status	   status;
231
232	devfs_get_cdevpriv((void **)&softc);
233
234	switch (cmd) {
235	case TARGIOCENABLE:
236	{
237		struct ioc_enable_lun	*new_lun;
238		struct cam_path		*path;
239
240		new_lun = (struct ioc_enable_lun *)addr;
241		status = xpt_create_path(&path, /*periph*/NULL,
242					  new_lun->path_id,
243					  new_lun->target_id,
244					  new_lun->lun_id);
245		if (status != CAM_REQ_CMP) {
246			printf("Couldn't create path, status %#x\n", status);
247			break;
248		}
249		xpt_path_lock(path);
250		status = targenable(softc, path, new_lun->grp6_len,
251				    new_lun->grp7_len);
252		xpt_path_unlock(path);
253		xpt_free_path(path);
254		break;
255	}
256	case TARGIOCDISABLE:
257		if (softc->periph == NULL) {
258			status = CAM_DEV_NOT_THERE;
259			break;
260		}
261		cam_periph_lock(softc->periph);
262		status = targdisable(softc);
263		cam_periph_unlock(softc->periph);
264		break;
265	case TARGIOCDEBUG:
266	{
267		struct ccb_debug cdbg;
268
269		/* If no periph available, disallow debugging changes */
270		if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
271			status = CAM_DEV_NOT_THERE;
272			break;
273		}
274		bzero(&cdbg, sizeof cdbg);
275		if (*((int *)addr) != 0)
276			cdbg.flags = CAM_DEBUG_PERIPH;
277		else
278			cdbg.flags = CAM_DEBUG_NONE;
279		xpt_setup_ccb(&cdbg.ccb_h, softc->path, CAM_PRIORITY_NORMAL);
280		cdbg.ccb_h.func_code = XPT_DEBUG;
281		cdbg.ccb_h.cbfcnp = targdone;
282		xpt_action((union ccb *)&cdbg);
283		status = cdbg.ccb_h.status & CAM_STATUS_MASK;
284		break;
285	}
286	default:
287		status = CAM_PROVIDE_FAIL;
288		break;
289	}
290
291	return (targcamstatus(status));
292}
293
294/* Writes are always ready, reads wait for user_ccb_queue or abort_queue */
295static int
296targpoll(struct cdev *dev, int poll_events, struct thread *td)
297{
298	struct targ_softc *softc;
299	int	revents;
300
301	devfs_get_cdevpriv((void **)&softc);
302
303	/* Poll for write() is always ok. */
304	revents = poll_events & (POLLOUT | POLLWRNORM);
305	if ((poll_events & (POLLIN | POLLRDNORM)) != 0) {
306		/* Poll for read() depends on user and abort queues. */
307		cam_periph_lock(softc->periph);
308		if (!TAILQ_EMPTY(&softc->user_ccb_queue) ||
309		    !TAILQ_EMPTY(&softc->abort_queue)) {
310			revents |= poll_events & (POLLIN | POLLRDNORM);
311		}
312		cam_periph_unlock(softc->periph);
313		/* Only sleep if the user didn't poll for write. */
314		if (revents == 0)
315			selrecord(td, &softc->read_select);
316	}
317
318	return (revents);
319}
320
321static int
322targkqfilter(struct cdev *dev, struct knote *kn)
323{
324	struct  targ_softc *softc;
325
326	devfs_get_cdevpriv((void **)&softc);
327	kn->kn_hook = (caddr_t)softc;
328	kn->kn_fop = &targread_filtops;
329	knlist_add(&softc->read_select.si_note, kn, 0);
330	return (0);
331}
332
333static void
334targreadfiltdetach(struct knote *kn)
335{
336	struct  targ_softc *softc;
337
338	softc = (struct targ_softc *)kn->kn_hook;
339	knlist_remove(&softc->read_select.si_note, kn, 0);
340}
341
342/* Notify the user's kqueue when the user queue or abort queue gets a CCB */
343static int
344targreadfilt(struct knote *kn, long hint)
345{
346	struct targ_softc *softc;
347	int	retval;
348
349	softc = (struct targ_softc *)kn->kn_hook;
350	cam_periph_lock(softc->periph);
351	retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
352		 !TAILQ_EMPTY(&softc->abort_queue);
353	cam_periph_unlock(softc->periph);
354	return (retval);
355}
356
357/* Send the HBA the enable/disable message */
358static cam_status
359targendislun(struct cam_path *path, int enable, int grp6_len, int grp7_len)
360{
361	struct ccb_en_lun en_ccb;
362	cam_status	  status;
363
364	/* Tell the lun to begin answering selects */
365	xpt_setup_ccb(&en_ccb.ccb_h, path, CAM_PRIORITY_NORMAL);
366	en_ccb.ccb_h.func_code = XPT_EN_LUN;
367	/* Don't need support for any vendor specific commands */
368	en_ccb.grp6_len = grp6_len;
369	en_ccb.grp7_len = grp7_len;
370	en_ccb.enable = enable ? 1 : 0;
371	xpt_action((union ccb *)&en_ccb);
372	status = en_ccb.ccb_h.status & CAM_STATUS_MASK;
373	if (status != CAM_REQ_CMP) {
374		xpt_print(path, "%sable lun CCB rejected, status %#x\n",
375		    enable ? "en" : "dis", status);
376	}
377	return (status);
378}
379
380/* Enable target mode on a LUN, given its path */
381static cam_status
382targenable(struct targ_softc *softc, struct cam_path *path, int grp6_len,
383	   int grp7_len)
384{
385	struct cam_periph *periph;
386	struct ccb_pathinq cpi;
387	cam_status	   status;
388
389	if ((softc->state & TARG_STATE_LUN_ENABLED) != 0)
390		return (CAM_LUN_ALRDY_ENA);
391
392	/* Make sure SIM supports target mode */
393	xpt_setup_ccb(&cpi.ccb_h, path, CAM_PRIORITY_NORMAL);
394	cpi.ccb_h.func_code = XPT_PATH_INQ;
395	xpt_action((union ccb *)&cpi);
396	status = cpi.ccb_h.status & CAM_STATUS_MASK;
397	if (status != CAM_REQ_CMP) {
398		printf("pathinq failed, status %#x\n", status);
399		goto enable_fail;
400	}
401	if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
402		printf("controller does not support target mode\n");
403		status = CAM_FUNC_NOTAVAIL;
404		goto enable_fail;
405	}
406
407	/* Destroy any periph on our path if it is disabled */
408	periph = cam_periph_find(path, "targ");
409	if (periph != NULL) {
410		struct targ_softc *del_softc;
411
412		del_softc = (struct targ_softc *)periph->softc;
413		if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
414			cam_periph_invalidate(del_softc->periph);
415			del_softc->periph = NULL;
416		} else {
417			printf("Requested path still in use by targ%d\n",
418			       periph->unit_number);
419			status = CAM_LUN_ALRDY_ENA;
420			goto enable_fail;
421		}
422	}
423
424	/* Create a periph instance attached to this path */
425	status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
426			"targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
427	if (status != CAM_REQ_CMP) {
428		printf("cam_periph_alloc failed, status %#x\n", status);
429		goto enable_fail;
430	}
431
432	/* Ensure that the periph now exists. */
433	if (cam_periph_find(path, "targ") == NULL) {
434		panic("targenable: succeeded but no periph?");
435		/* NOTREACHED */
436	}
437
438	/* Send the enable lun message */
439	status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
440	if (status != CAM_REQ_CMP) {
441		printf("enable lun failed, status %#x\n", status);
442		goto enable_fail;
443	}
444	softc->state |= TARG_STATE_LUN_ENABLED;
445
446enable_fail:
447	return (status);
448}
449
450/* Disable this softc's target instance if enabled */
451static cam_status
452targdisable(struct targ_softc *softc)
453{
454	cam_status status;
455
456	if ((softc->state & TARG_STATE_LUN_ENABLED) == 0)
457		return (CAM_REQ_CMP);
458
459	CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targdisable\n"));
460
461	/* Abort any ccbs pending on the controller */
462	abort_all_pending(softc);
463
464	/* Disable this lun */
465	status = targendislun(softc->path, /*enable*/0,
466			      /*grp6_len*/0, /*grp7_len*/0);
467	if (status == CAM_REQ_CMP)
468		softc->state &= ~TARG_STATE_LUN_ENABLED;
469	else
470		printf("Disable lun failed, status %#x\n", status);
471
472	return (status);
473}
474
475/* Initialize a periph (called from cam_periph_alloc) */
476static cam_status
477targctor(struct cam_periph *periph, void *arg)
478{
479	struct targ_softc *softc;
480
481	/* Store pointer to softc for periph-driven routines */
482	softc = (struct targ_softc *)arg;
483	periph->softc = softc;
484	softc->periph = periph;
485	softc->path = periph->path;
486	return (CAM_REQ_CMP);
487}
488
489static void
490targdtor(struct cam_periph *periph)
491{
492	struct targ_softc     *softc;
493	struct ccb_hdr	      *ccb_h;
494	struct targ_cmd_descr *descr;
495
496	softc = (struct targ_softc *)periph->softc;
497
498	/*
499	 * targdisable() aborts CCBs back to the user and leaves them
500	 * on user_ccb_queue and abort_queue in case the user is still
501	 * interested in them.  We free them now.
502	 */
503	while ((ccb_h = TAILQ_FIRST(&softc->user_ccb_queue)) != NULL) {
504		TAILQ_REMOVE(&softc->user_ccb_queue, ccb_h, periph_links.tqe);
505		targfreeccb(softc, (union ccb *)ccb_h);
506	}
507	while ((descr = TAILQ_FIRST(&softc->abort_queue)) != NULL) {
508		TAILQ_REMOVE(&softc->abort_queue, descr, tqe);
509		free(descr, M_TARG);
510	}
511
512	softc->periph = NULL;
513	softc->path = NULL;
514	periph->softc = NULL;
515}
516
517/* Receive CCBs from user mode proc and send them to the HBA */
518static int
519targwrite(struct cdev *dev, struct uio *uio, int ioflag)
520{
521	union ccb *user_ccb;
522	struct targ_softc *softc;
523	struct targ_cmd_descr *descr;
524	int write_len, error;
525	int func_code, priority;
526
527	devfs_get_cdevpriv((void **)&softc);
528	write_len = error = 0;
529	CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
530		  ("write - uio_resid %zd\n", uio->uio_resid));
531	while (uio->uio_resid >= sizeof(user_ccb) && error == 0) {
532		union ccb *ccb;
533
534		error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
535		if (error != 0) {
536			CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
537				  ("write - uiomove failed (%d)\n", error));
538			break;
539		}
540		priority = fuword32(&user_ccb->ccb_h.pinfo.priority);
541		if (priority == CAM_PRIORITY_NONE) {
542			error = EINVAL;
543			break;
544		}
545		func_code = fuword32(&user_ccb->ccb_h.func_code);
546		switch (func_code) {
547		case XPT_ACCEPT_TARGET_IO:
548		case XPT_IMMED_NOTIFY:
549		case XPT_IMMEDIATE_NOTIFY:
550			cam_periph_lock(softc->periph);
551			ccb = targgetccb(softc, func_code, priority);
552			descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
553			descr->user_ccb = user_ccb;
554			descr->func_code = func_code;
555			CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
556				  ("Sent ATIO/INOT (%p)\n", user_ccb));
557			xpt_action(ccb);
558			TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
559					  &ccb->ccb_h,
560					  periph_links.tqe);
561			cam_periph_unlock(softc->periph);
562			break;
563		default:
564			cam_periph_lock(softc->periph);
565			if ((func_code & XPT_FC_QUEUED) != 0) {
566				CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
567					  ("Sending queued ccb %#x (%p)\n",
568					  func_code, user_ccb));
569				descr = targgetdescr(softc);
570				descr->user_ccb = user_ccb;
571				descr->priority = priority;
572				descr->func_code = func_code;
573				TAILQ_INSERT_TAIL(&softc->work_queue,
574						  descr, tqe);
575				xpt_schedule(softc->periph, priority);
576			} else {
577				CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
578					  ("Sending inline ccb %#x (%p)\n",
579					  func_code, user_ccb));
580				ccb = targgetccb(softc, func_code, priority);
581				descr = (struct targ_cmd_descr *)
582					 ccb->ccb_h.targ_descr;
583				descr->user_ccb = user_ccb;
584				descr->priority = priority;
585				descr->func_code = func_code;
586				if (targusermerge(softc, descr, ccb) != EFAULT)
587					targsendccb(softc, ccb, descr);
588				targreturnccb(softc, ccb);
589			}
590			cam_periph_unlock(softc->periph);
591			break;
592		}
593		write_len += sizeof(user_ccb);
594	}
595
596	/*
597	 * If we've successfully taken in some amount of
598	 * data, return success for that data first.  If
599	 * an error is persistent, it will be reported
600	 * on the next write.
601	 */
602	if (error != 0 && write_len == 0)
603		return (error);
604	if (write_len == 0 && uio->uio_resid != 0)
605		return (ENOSPC);
606	return (0);
607}
608
609/* Process requests (descrs) via the periph-supplied CCBs */
610static void
611targstart(struct cam_periph *periph, union ccb *start_ccb)
612{
613	struct targ_softc *softc;
614	struct targ_cmd_descr *descr, *next_descr;
615	int error;
616
617	softc = (struct targ_softc *)periph->softc;
618	CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
619
620	descr = TAILQ_FIRST(&softc->work_queue);
621	if (descr == NULL) {
622		xpt_release_ccb(start_ccb);
623	} else {
624		TAILQ_REMOVE(&softc->work_queue, descr, tqe);
625		next_descr = TAILQ_FIRST(&softc->work_queue);
626
627		/* Initiate a transaction using the descr and supplied CCB */
628		error = targusermerge(softc, descr, start_ccb);
629		if (error == 0)
630			error = targsendccb(softc, start_ccb, descr);
631		if (error != 0) {
632			xpt_print(periph->path,
633			    "targsendccb failed, err %d\n", error);
634			xpt_release_ccb(start_ccb);
635			suword(&descr->user_ccb->ccb_h.status,
636			       CAM_REQ_CMP_ERR);
637			TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
638			notify_user(softc);
639		}
640
641		/* If we have more work to do, stay scheduled */
642		if (next_descr != NULL)
643			xpt_schedule(periph, next_descr->priority);
644	}
645}
646
647static int
648targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
649	      union ccb *ccb)
650{
651	struct ccb_hdr *u_ccbh, *k_ccbh;
652	size_t ccb_len;
653	int error;
654
655	u_ccbh = &descr->user_ccb->ccb_h;
656	k_ccbh = &ccb->ccb_h;
657
658	/*
659	 * There are some fields in the CCB header that need to be
660	 * preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
661	 */
662	xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
663	k_ccbh->retry_count = fuword32(&u_ccbh->retry_count);
664	k_ccbh->func_code = descr->func_code;
665	k_ccbh->flags = fuword32(&u_ccbh->flags);
666	k_ccbh->timeout = fuword32(&u_ccbh->timeout);
667	ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
668	error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
669	if (error != 0) {
670		k_ccbh->status = CAM_REQ_CMP_ERR;
671		return (error);
672	}
673
674	/* Translate usermode abort_ccb pointer to its kernel counterpart */
675	if (k_ccbh->func_code == XPT_ABORT) {
676		struct ccb_abort *cab;
677		struct ccb_hdr *ccb_h;
678
679		cab = (struct ccb_abort *)ccb;
680		TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
681		    periph_links.tqe) {
682			struct targ_cmd_descr *ab_descr;
683
684			ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
685			if (ab_descr->user_ccb == cab->abort_ccb) {
686				CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
687					  ("Changing abort for %p to %p\n",
688					  cab->abort_ccb, ccb_h));
689				cab->abort_ccb = (union ccb *)ccb_h;
690				break;
691			}
692		}
693		/* CCB not found, set appropriate status */
694		if (ccb_h == NULL) {
695			k_ccbh->status = CAM_PATH_INVALID;
696			error = ESRCH;
697		}
698	}
699
700	return (error);
701}
702
703/* Build and send a kernel CCB formed from descr->user_ccb */
704static int
705targsendccb(struct targ_softc *softc, union ccb *ccb,
706	    struct targ_cmd_descr *descr)
707{
708	struct cam_periph_map_info *mapinfo;
709	struct ccb_hdr *ccb_h;
710	int error;
711
712	ccb_h = &ccb->ccb_h;
713	mapinfo = &descr->mapinfo;
714	mapinfo->num_bufs_used = 0;
715
716	/*
717	 * There's no way for the user to have a completion
718	 * function, so we put our own completion function in here.
719	 * We also stash in a reference to our descriptor so targreturnccb()
720	 * can find our mapping info.
721	 */
722	ccb_h->cbfcnp = targdone;
723	ccb_h->targ_descr = descr;
724
725	if ((ccb_h->func_code == XPT_CONT_TARGET_IO) ||
726	    (ccb_h->func_code == XPT_DEV_MATCH)) {
727
728		error = cam_periph_mapmem(ccb, mapinfo);
729
730		/*
731		 * cam_periph_mapmem returned an error, we can't continue.
732		 * Return the error to the user.
733		 */
734		if (error) {
735			ccb_h->status = CAM_REQ_CMP_ERR;
736			mapinfo->num_bufs_used = 0;
737			return (error);
738		}
739	}
740
741	/*
742	 * Once queued on the pending CCB list, this CCB will be protected
743	 * by our error recovery handler.
744	 */
745	CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
746	if (XPT_FC_IS_QUEUED(ccb)) {
747		TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
748				  periph_links.tqe);
749	}
750	xpt_action(ccb);
751
752	return (0);
753}
754
755/* Completion routine for CCBs (called at splsoftcam) */
756static void
757targdone(struct cam_periph *periph, union ccb *done_ccb)
758{
759	struct targ_softc *softc;
760	cam_status status;
761
762	CAM_DEBUG(periph->path, CAM_DEBUG_PERIPH, ("targdone %p\n", done_ccb));
763	softc = (struct targ_softc *)periph->softc;
764	TAILQ_REMOVE(&softc->pending_ccb_queue, &done_ccb->ccb_h,
765		     periph_links.tqe);
766	status = done_ccb->ccb_h.status & CAM_STATUS_MASK;
767
768	/* If we're no longer enabled, throw away CCB */
769	if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
770		targfreeccb(softc, done_ccb);
771		return;
772	}
773	/* abort_all_pending() waits for pending queue to be empty */
774	if (TAILQ_EMPTY(&softc->pending_ccb_queue))
775		wakeup(&softc->pending_ccb_queue);
776
777	switch (done_ccb->ccb_h.func_code) {
778	/* All FC_*_QUEUED CCBs go back to userland */
779	case XPT_IMMED_NOTIFY:
780	case XPT_IMMEDIATE_NOTIFY:
781	case XPT_ACCEPT_TARGET_IO:
782	case XPT_CONT_TARGET_IO:
783		TAILQ_INSERT_TAIL(&softc->user_ccb_queue, &done_ccb->ccb_h,
784				  periph_links.tqe);
785 		cam_periph_unlock(softc->periph);
786		notify_user(softc);
787 		cam_periph_lock(softc->periph);
788		break;
789	default:
790		panic("targdone: impossible xpt opcode %#x",
791		      done_ccb->ccb_h.func_code);
792		/* NOTREACHED */
793	}
794}
795
796/* Return CCBs to the user from the user queue and abort queue */
797static int
798targread(struct cdev *dev, struct uio *uio, int ioflag)
799{
800	struct descr_queue	*abort_queue;
801	struct targ_cmd_descr	*user_descr;
802	struct targ_softc	*softc;
803	struct ccb_queue  *user_queue;
804	struct ccb_hdr	  *ccb_h;
805	union  ccb	  *user_ccb;
806	int		   read_len, error;
807
808	error = 0;
809	read_len = 0;
810	devfs_get_cdevpriv((void **)&softc);
811	user_queue = &softc->user_ccb_queue;
812	abort_queue = &softc->abort_queue;
813	CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targread\n"));
814
815	/* If no data is available, wait or return immediately */
816	cam_periph_lock(softc->periph);
817	ccb_h = TAILQ_FIRST(user_queue);
818	user_descr = TAILQ_FIRST(abort_queue);
819	while (ccb_h == NULL && user_descr == NULL) {
820		if ((ioflag & IO_NDELAY) == 0) {
821			error = cam_periph_sleep(softc->periph, user_queue,
822			    PRIBIO | PCATCH, "targrd", 0);
823			ccb_h = TAILQ_FIRST(user_queue);
824			user_descr = TAILQ_FIRST(abort_queue);
825			if (error != 0) {
826				if (error == ERESTART) {
827					continue;
828				} else {
829					goto read_fail;
830				}
831			}
832		} else {
833			cam_periph_unlock(softc->periph);
834			return (EAGAIN);
835		}
836	}
837
838	/* Data is available so fill the user's buffer */
839	while (ccb_h != NULL) {
840		struct targ_cmd_descr *descr;
841
842		if (uio->uio_resid < sizeof(user_ccb))
843			break;
844		TAILQ_REMOVE(user_queue, ccb_h, periph_links.tqe);
845		descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
846		user_ccb = descr->user_ccb;
847		CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
848			  ("targread ccb %p (%p)\n", ccb_h, user_ccb));
849		error = targreturnccb(softc, (union ccb *)ccb_h);
850		if (error != 0)
851			goto read_fail;
852		cam_periph_unlock(softc->periph);
853		error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
854		cam_periph_lock(softc->periph);
855		if (error != 0)
856			goto read_fail;
857		read_len += sizeof(user_ccb);
858
859		ccb_h = TAILQ_FIRST(user_queue);
860	}
861
862	/* Flush out any aborted descriptors */
863	while (user_descr != NULL) {
864		if (uio->uio_resid < sizeof(user_ccb))
865			break;
866		TAILQ_REMOVE(abort_queue, user_descr, tqe);
867		user_ccb = user_descr->user_ccb;
868		CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
869			  ("targread aborted descr %p (%p)\n",
870			  user_descr, user_ccb));
871		suword(&user_ccb->ccb_h.status, CAM_REQ_ABORTED);
872		cam_periph_unlock(softc->periph);
873		error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
874		cam_periph_lock(softc->periph);
875		if (error != 0)
876			goto read_fail;
877		read_len += sizeof(user_ccb);
878
879		user_descr = TAILQ_FIRST(abort_queue);
880	}
881
882	/*
883	 * If we've successfully read some amount of data, don't report an
884	 * error.  If the error is persistent, it will be reported on the
885	 * next read().
886	 */
887	if (read_len == 0 && uio->uio_resid != 0)
888		error = ENOSPC;
889
890read_fail:
891	cam_periph_unlock(softc->periph);
892	return (error);
893}
894
895/* Copy completed ccb back to the user */
896static int
897targreturnccb(struct targ_softc *softc, union ccb *ccb)
898{
899	struct targ_cmd_descr *descr;
900	struct ccb_hdr *u_ccbh;
901	size_t ccb_len;
902	int error;
903
904	CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
905	descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
906	u_ccbh = &descr->user_ccb->ccb_h;
907
908	/* Copy out the central portion of the ccb_hdr */
909	copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
910		offsetof(struct ccb_hdr, periph_priv) -
911		offsetof(struct ccb_hdr, retry_count));
912
913	/* Copy out the rest of the ccb (after the ccb_hdr) */
914	ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
915	if (descr->mapinfo.num_bufs_used != 0)
916		cam_periph_unmapmem(ccb, &descr->mapinfo);
917	error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
918	if (error != 0) {
919		xpt_print(softc->path,
920		    "targreturnccb - CCB copyout failed (%d)\n", error);
921	}
922	/* Free CCB or send back to devq. */
923	targfreeccb(softc, ccb);
924
925	return (error);
926}
927
928static union ccb *
929targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
930{
931	union ccb *ccb;
932	int ccb_len;
933
934	ccb_len = targccblen(type);
935	ccb = malloc(ccb_len, M_TARG, M_NOWAIT);
936	CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
937	if (ccb == NULL) {
938		return (ccb);
939	}
940	xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
941	ccb->ccb_h.func_code = type;
942	ccb->ccb_h.cbfcnp = targdone;
943	ccb->ccb_h.targ_descr = targgetdescr(softc);
944	if (ccb->ccb_h.targ_descr == NULL) {
945		free (ccb, M_TARG);
946		ccb = NULL;
947	}
948	return (ccb);
949}
950
951static void
952targfreeccb(struct targ_softc *softc, union ccb *ccb)
953{
954	CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
955			ccb->ccb_h.targ_descr));
956	free(ccb->ccb_h.targ_descr, M_TARG);
957
958	switch (ccb->ccb_h.func_code) {
959	case XPT_ACCEPT_TARGET_IO:
960	case XPT_IMMED_NOTIFY:
961	case XPT_IMMEDIATE_NOTIFY:
962		CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
963		free(ccb, M_TARG);
964		break;
965	default:
966		/* Send back CCB if we got it from the periph */
967		if (XPT_FC_IS_QUEUED(ccb)) {
968			CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
969					("returning queued ccb %p\n", ccb));
970			xpt_release_ccb(ccb);
971		} else {
972			CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
973					("freeing ccb %p\n", ccb));
974			free(ccb, M_TARG);
975		}
976		break;
977	}
978}
979
980static struct targ_cmd_descr *
981targgetdescr(struct targ_softc *softc)
982{
983	struct targ_cmd_descr *descr;
984
985	descr = malloc(sizeof(*descr), M_TARG,
986	       M_NOWAIT);
987	if (descr) {
988		descr->mapinfo.num_bufs_used = 0;
989	}
990	return (descr);
991}
992
993static void
994targinit(void)
995{
996	struct cdev *dev;
997
998	/* Add symbolic link to targ0 for compatibility. */
999	dev = make_dev(&targ_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "targ");
1000	make_dev_alias(dev, "targ0");
1001}
1002
1003static void
1004targasync(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg)
1005{
1006	/* All events are handled in usermode by INOTs */
1007	panic("targasync() called, should be an INOT instead");
1008}
1009
1010/* Cancel all pending requests and CCBs awaiting work. */
1011static void
1012abort_all_pending(struct targ_softc *softc)
1013{
1014	struct targ_cmd_descr   *descr;
1015	struct ccb_abort	 cab;
1016	struct ccb_hdr		*ccb_h;
1017
1018	CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("abort_all_pending\n"));
1019
1020	/* First abort the descriptors awaiting resources */
1021	while ((descr = TAILQ_FIRST(&softc->work_queue)) != NULL) {
1022		CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1023			  ("Aborting descr from workq %p\n", descr));
1024		TAILQ_REMOVE(&softc->work_queue, descr, tqe);
1025		TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
1026	}
1027
1028	/*
1029	 * Then abort all pending CCBs.
1030	 * targdone() will return the aborted CCB via user_ccb_queue
1031	 */
1032	xpt_setup_ccb(&cab.ccb_h, softc->path, CAM_PRIORITY_NORMAL);
1033	cab.ccb_h.func_code = XPT_ABORT;
1034	cab.ccb_h.status = CAM_REQ_CMP_ERR;
1035	TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue, periph_links.tqe) {
1036		CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1037			  ("Aborting pending CCB %p\n", ccb_h));
1038		cab.abort_ccb = (union ccb *)ccb_h;
1039		xpt_action((union ccb *)&cab);
1040		if (cab.ccb_h.status != CAM_REQ_CMP) {
1041			xpt_print(cab.ccb_h.path,
1042			    "Unable to abort CCB, status %#x\n",
1043			    cab.ccb_h.status);
1044		}
1045	}
1046
1047	/* If we aborted at least one pending CCB ok, wait for it. */
1048	if (cab.ccb_h.status == CAM_REQ_CMP) {
1049		cam_periph_sleep(softc->periph, &softc->pending_ccb_queue,
1050		       PRIBIO | PCATCH, "tgabrt", 0);
1051	}
1052
1053	/* If we aborted anything from the work queue, wakeup user. */
1054	if (!TAILQ_EMPTY(&softc->user_ccb_queue)
1055	 || !TAILQ_EMPTY(&softc->abort_queue)) {
1056		cam_periph_unlock(softc->periph);
1057		notify_user(softc);
1058		cam_periph_lock(softc->periph);
1059	}
1060}
1061
1062/* Notify the user that data is ready */
1063static void
1064notify_user(struct targ_softc *softc)
1065{
1066	/*
1067	 * Notify users sleeping via poll(), kqueue(), and
1068	 * blocking read().
1069	 */
1070	selwakeuppri(&softc->read_select, PRIBIO);
1071	KNOTE_UNLOCKED(&softc->read_select.si_note, 0);
1072	wakeup(&softc->user_ccb_queue);
1073}
1074
1075/* Convert CAM status to errno values */
1076static int
1077targcamstatus(cam_status status)
1078{
1079	switch (status & CAM_STATUS_MASK) {
1080	case CAM_REQ_CMP:	/* CCB request completed without error */
1081		return (0);
1082	case CAM_REQ_INPROG:	/* CCB request is in progress */
1083		return (EINPROGRESS);
1084	case CAM_REQ_CMP_ERR:	/* CCB request completed with an error */
1085		return (EIO);
1086	case CAM_PROVIDE_FAIL:	/* Unable to provide requested capability */
1087		return (ENOTTY);
1088	case CAM_FUNC_NOTAVAIL:	/* The requested function is not available */
1089		return (ENOTSUP);
1090	case CAM_LUN_ALRDY_ENA:	/* LUN is already enabled for target mode */
1091		return (EADDRINUSE);
1092	case CAM_PATH_INVALID:	/* Supplied Path ID is invalid */
1093	case CAM_DEV_NOT_THERE:	/* SCSI Device Not Installed/there */
1094		return (ENOENT);
1095	case CAM_REQ_ABORTED:	/* CCB request aborted by the host */
1096		return (ECANCELED);
1097	case CAM_CMD_TIMEOUT:	/* Command timeout */
1098		return (ETIMEDOUT);
1099	case CAM_REQUEUE_REQ:	/* Requeue to preserve transaction ordering */
1100		return (EAGAIN);
1101	case CAM_REQ_INVALID:	/* CCB request was invalid */
1102		return (EINVAL);
1103	case CAM_RESRC_UNAVAIL:	/* Resource Unavailable */
1104		return (ENOMEM);
1105	case CAM_BUSY:		/* CAM subsystem is busy */
1106	case CAM_UA_ABORT:	/* Unable to abort CCB request */
1107		return (EBUSY);
1108	default:
1109		return (ENXIO);
1110	}
1111}
1112
1113static size_t
1114targccblen(xpt_opcode func_code)
1115{
1116	int len;
1117
1118	/* Codes we expect to see as a target */
1119	switch (func_code) {
1120	case XPT_CONT_TARGET_IO:
1121	case XPT_SCSI_IO:
1122		len = sizeof(struct ccb_scsiio);
1123		break;
1124	case XPT_ACCEPT_TARGET_IO:
1125		len = sizeof(struct ccb_accept_tio);
1126		break;
1127	case XPT_IMMED_NOTIFY:
1128		len = sizeof(struct ccb_immed_notify);
1129		break;
1130	case XPT_IMMEDIATE_NOTIFY:
1131		len = sizeof(struct ccb_immediate_notify);
1132		break;
1133	case XPT_REL_SIMQ:
1134		len = sizeof(struct ccb_relsim);
1135		break;
1136	case XPT_PATH_INQ:
1137		len = sizeof(struct ccb_pathinq);
1138		break;
1139	case XPT_DEBUG:
1140		len = sizeof(struct ccb_debug);
1141		break;
1142	case XPT_ABORT:
1143		len = sizeof(struct ccb_abort);
1144		break;
1145	case XPT_EN_LUN:
1146		len = sizeof(struct ccb_en_lun);
1147		break;
1148	default:
1149		len = sizeof(union ccb);
1150		break;
1151	}
1152
1153	return (len);
1154}
1155