1 /*-
2 * Generic SCSI Target Kernel Mode Driver
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 *
6 * Copyright (c) 2002 Nate Lawson.
7 * Copyright (c) 1998, 1999, 2001, 2002 Justin T. Gibbs.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions, and the following disclaimer,
15 * without modification, immediately at the beginning of the file.
16 * 2. The name of the author may not be used to endorse or promote products
17 * derived from this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
23 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/conf.h>
36 #include <sys/malloc.h>
37 #include <sys/poll.h>
38 #include <sys/vnode.h>
39 #include <sys/lock.h>
40 #include <sys/mutex.h>
41 #include <sys/devicestat.h>
42 #include <sys/proc.h>
43 /* Includes to support callout */
44 #include <sys/types.h>
45 #include <sys/systm.h>
46
47 #include <cam/cam.h>
48 #include <cam/cam_ccb.h>
49 #include <cam/cam_periph.h>
50 #include <cam/cam_xpt_periph.h>
51 #include <cam/cam_sim.h>
52 #include <cam/scsi/scsi_targetio.h>
53
54 /* Transaction information attached to each CCB sent by the user */
55 struct targ_cmd_descr {
56 struct cam_periph_map_info mapinfo;
57 TAILQ_ENTRY(targ_cmd_descr) tqe;
58 union ccb *user_ccb;
59 int priority;
60 int func_code;
61 };
62
63 /* Offset into the private CCB area for storing our descriptor */
64 #define targ_descr periph_priv.entries[1].ptr
65
66 TAILQ_HEAD(descr_queue, targ_cmd_descr);
67
68 typedef enum {
69 TARG_STATE_RESV = 0x00, /* Invalid state */
70 TARG_STATE_OPENED = 0x01, /* Device opened, softc initialized */
71 TARG_STATE_LUN_ENABLED = 0x02 /* Device enabled for a path */
72 } targ_state;
73
74 /* Per-instance device software context */
75 struct targ_softc {
76 /* CCBs (CTIOs, ATIOs, INOTs) pending on the controller */
77 struct ccb_queue pending_ccb_queue;
78
79 /* Command descriptors awaiting CTIO resources from the XPT */
80 struct descr_queue work_queue;
81
82 /* Command descriptors that have been aborted back to the user. */
83 struct descr_queue abort_queue;
84
85 /*
86 * Queue of CCBs that have been copied out to userland, but our
87 * userland daemon has not yet seen.
88 */
89 struct ccb_queue user_ccb_queue;
90
91 struct cam_periph *periph;
92 struct cam_path *path;
93 targ_state state;
94 u_int maxio;
95 struct selinfo read_select;
96 struct devstat device_stats;
97 };
98
99 static d_open_t targopen;
100 static d_read_t targread;
101 static d_write_t targwrite;
102 static d_ioctl_t targioctl;
103 static d_poll_t targpoll;
104 static d_kqfilter_t targkqfilter;
105 static void targreadfiltdetach(struct knote *kn);
106 static int targreadfilt(struct knote *kn, long hint);
107 static const struct filterops targread_filtops = {
108 .f_isfd = 1,
109 .f_detach = targreadfiltdetach,
110 .f_event = targreadfilt,
111 .f_copy = knote_triv_copy,
112 };
113
114 static struct cdevsw targ_cdevsw = {
115 .d_version = D_VERSION,
116 .d_open = targopen,
117 .d_read = targread,
118 .d_write = targwrite,
119 .d_ioctl = targioctl,
120 .d_poll = targpoll,
121 .d_name = "targ",
122 .d_kqfilter = targkqfilter
123 };
124
125 static cam_status targendislun(struct cam_path *path, int enable,
126 int grp6_len, int grp7_len);
127 static cam_status targenable(struct targ_softc *softc,
128 struct cam_path *path,
129 int grp6_len, int grp7_len);
130 static cam_status targdisable(struct targ_softc *softc);
131 static periph_ctor_t targctor;
132 static periph_dtor_t targdtor;
133 static periph_start_t targstart;
134 static int targusermerge(struct targ_softc *softc,
135 struct targ_cmd_descr *descr,
136 union ccb *ccb);
137 static int targsendccb(struct targ_softc *softc, union ccb *ccb,
138 struct targ_cmd_descr *descr);
139 static void targdone(struct cam_periph *periph,
140 union ccb *done_ccb);
141 static int targreturnccb(struct targ_softc *softc,
142 union ccb *ccb);
143 static union ccb * targgetccb(struct targ_softc *softc, xpt_opcode type,
144 int priority);
145 static void targfreeccb(struct targ_softc *softc, union ccb *ccb);
146 static struct targ_cmd_descr *
147 targgetdescr(struct targ_softc *softc);
148 static periph_init_t targinit;
149 static void targasync(void *callback_arg, uint32_t code,
150 struct cam_path *path, void *arg);
151 static void abort_all_pending(struct targ_softc *softc);
152 static void notify_user(struct targ_softc *softc);
153 static int targcamstatus(cam_status status);
154 static size_t targccblen(xpt_opcode func_code);
155
156 static struct periph_driver targdriver =
157 {
158 targinit, "targ",
159 TAILQ_HEAD_INITIALIZER(targdriver.units), /* generation */ 0
160 };
161 PERIPHDRIVER_DECLARE(targ, targdriver);
162
163 static MALLOC_DEFINE(M_TARG, "TARG", "TARG data");
164
165 /* Disable LUN if enabled and teardown softc */
166 static void
targcdevdtor(void * data)167 targcdevdtor(void *data)
168 {
169 struct targ_softc *softc;
170 struct cam_periph *periph;
171
172 softc = data;
173 if (softc->periph == NULL) {
174 printf("%s: destroying non-enabled target\n", __func__);
175 free(softc, M_TARG);
176 return;
177 }
178
179 /*
180 * Acquire a hold on the periph so that it doesn't go away before
181 * we are ready at the end of the function.
182 */
183 periph = softc->periph;
184 cam_periph_acquire(periph);
185 cam_periph_lock(periph);
186 (void)targdisable(softc);
187 if (softc->periph != NULL) {
188 cam_periph_invalidate(softc->periph);
189 softc->periph = NULL;
190 }
191 cam_periph_unlock(periph);
192 cam_periph_release(periph);
193 free(softc, M_TARG);
194 }
195
196 /*
197 * Create softc and initialize it. There is no locking here because a
198 * periph doesn't get created until an ioctl is issued to do so, and
199 * that can't happen until this method returns.
200 */
201 static int
targopen(struct cdev * dev,int flags,int fmt,struct thread * td)202 targopen(struct cdev *dev, int flags, int fmt, struct thread *td)
203 {
204 struct targ_softc *softc;
205
206 /* Allocate its softc, initialize it */
207 softc = malloc(sizeof(*softc), M_TARG,
208 M_WAITOK | M_ZERO);
209 softc->state = TARG_STATE_OPENED;
210 softc->periph = NULL;
211 softc->path = NULL;
212
213 TAILQ_INIT(&softc->pending_ccb_queue);
214 TAILQ_INIT(&softc->work_queue);
215 TAILQ_INIT(&softc->abort_queue);
216 TAILQ_INIT(&softc->user_ccb_queue);
217 knlist_init_mtx(&softc->read_select.si_note, NULL);
218
219 devfs_set_cdevpriv(softc, targcdevdtor);
220 return (0);
221 }
222
223 /* Enable/disable LUNs, set debugging level */
224 static int
targioctl(struct cdev * dev,u_long cmd,caddr_t addr,int flag,struct thread * td)225 targioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
226 {
227 struct targ_softc *softc;
228 cam_status status;
229
230 devfs_get_cdevpriv((void **)&softc);
231
232 switch (cmd) {
233 case TARGIOCENABLE:
234 {
235 struct ioc_enable_lun *new_lun;
236 struct cam_path *path;
237
238 new_lun = (struct ioc_enable_lun *)addr;
239 status = xpt_create_path(&path, /*periph*/NULL,
240 new_lun->path_id,
241 new_lun->target_id,
242 new_lun->lun_id);
243 if (status != CAM_REQ_CMP) {
244 printf("Couldn't create path, status %#x\n", status);
245 break;
246 }
247 xpt_path_lock(path);
248 status = targenable(softc, path, new_lun->grp6_len,
249 new_lun->grp7_len);
250 xpt_path_unlock(path);
251 xpt_free_path(path);
252 break;
253 }
254 case TARGIOCDISABLE:
255 if (softc->periph == NULL) {
256 status = CAM_DEV_NOT_THERE;
257 break;
258 }
259 cam_periph_lock(softc->periph);
260 status = targdisable(softc);
261 cam_periph_unlock(softc->periph);
262 break;
263 case TARGIOCDEBUG:
264 {
265 struct ccb_debug cdbg;
266
267 /* If no periph available, disallow debugging changes */
268 if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
269 status = CAM_DEV_NOT_THERE;
270 break;
271 }
272 bzero(&cdbg, sizeof cdbg);
273 if (*((int *)addr) != 0)
274 cdbg.flags = CAM_DEBUG_PERIPH;
275 else
276 cdbg.flags = CAM_DEBUG_NONE;
277 xpt_setup_ccb(&cdbg.ccb_h, softc->path, CAM_PRIORITY_NORMAL);
278 cdbg.ccb_h.func_code = XPT_DEBUG;
279 cdbg.ccb_h.cbfcnp = targdone;
280 xpt_action((union ccb *)&cdbg);
281 status = cdbg.ccb_h.status & CAM_STATUS_MASK;
282 break;
283 }
284 default:
285 status = CAM_PROVIDE_FAIL;
286 break;
287 }
288
289 return (targcamstatus(status));
290 }
291
292 /* Writes are always ready, reads wait for user_ccb_queue or abort_queue */
293 static int
targpoll(struct cdev * dev,int poll_events,struct thread * td)294 targpoll(struct cdev *dev, int poll_events, struct thread *td)
295 {
296 struct targ_softc *softc;
297 int revents;
298
299 devfs_get_cdevpriv((void **)&softc);
300
301 /* Poll for write() is always ok. */
302 revents = poll_events & (POLLOUT | POLLWRNORM);
303 if ((poll_events & (POLLIN | POLLRDNORM)) != 0) {
304 /* Poll for read() depends on user and abort queues. */
305 cam_periph_lock(softc->periph);
306 if (!TAILQ_EMPTY(&softc->user_ccb_queue) ||
307 !TAILQ_EMPTY(&softc->abort_queue)) {
308 revents |= poll_events & (POLLIN | POLLRDNORM);
309 }
310 cam_periph_unlock(softc->periph);
311 /* Only sleep if the user didn't poll for write. */
312 if (revents == 0)
313 selrecord(td, &softc->read_select);
314 }
315
316 return (revents);
317 }
318
319 static int
targkqfilter(struct cdev * dev,struct knote * kn)320 targkqfilter(struct cdev *dev, struct knote *kn)
321 {
322 struct targ_softc *softc;
323
324 devfs_get_cdevpriv((void **)&softc);
325 kn->kn_hook = (caddr_t)softc;
326 kn->kn_fop = &targread_filtops;
327 knlist_add(&softc->read_select.si_note, kn, 0);
328 return (0);
329 }
330
331 static void
targreadfiltdetach(struct knote * kn)332 targreadfiltdetach(struct knote *kn)
333 {
334 struct targ_softc *softc;
335
336 softc = (struct targ_softc *)kn->kn_hook;
337 knlist_remove(&softc->read_select.si_note, kn, 0);
338 }
339
340 /* Notify the user's kqueue when the user queue or abort queue gets a CCB */
341 static int
targreadfilt(struct knote * kn,long hint)342 targreadfilt(struct knote *kn, long hint)
343 {
344 struct targ_softc *softc;
345 int retval;
346
347 softc = (struct targ_softc *)kn->kn_hook;
348 cam_periph_lock(softc->periph);
349 retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
350 !TAILQ_EMPTY(&softc->abort_queue);
351 cam_periph_unlock(softc->periph);
352 return (retval);
353 }
354
355 /* Send the HBA the enable/disable message */
356 static cam_status
targendislun(struct cam_path * path,int enable,int grp6_len,int grp7_len)357 targendislun(struct cam_path *path, int enable, int grp6_len, int grp7_len)
358 {
359 struct ccb_en_lun en_ccb;
360 cam_status status;
361
362 /* Tell the lun to begin answering selects */
363 memset(&en_ccb, 0, sizeof(en_ccb));
364 xpt_setup_ccb(&en_ccb.ccb_h, path, CAM_PRIORITY_NORMAL);
365 en_ccb.ccb_h.func_code = XPT_EN_LUN;
366 /* Don't need support for any vendor specific commands */
367 en_ccb.grp6_len = grp6_len;
368 en_ccb.grp7_len = grp7_len;
369 en_ccb.enable = enable ? 1 : 0;
370 xpt_action((union ccb *)&en_ccb);
371 status = en_ccb.ccb_h.status & CAM_STATUS_MASK;
372 if (status != CAM_REQ_CMP) {
373 xpt_print(path, "%sable lun CCB rejected, status %#x\n",
374 enable ? "en" : "dis", status);
375 }
376 return (status);
377 }
378
379 /* Enable target mode on a LUN, given its path */
380 static cam_status
targenable(struct targ_softc * softc,struct cam_path * path,int grp6_len,int grp7_len)381 targenable(struct targ_softc *softc, struct cam_path *path, int grp6_len,
382 int grp7_len)
383 {
384 struct cam_periph *periph;
385 struct ccb_pathinq cpi;
386 cam_status status;
387
388 if ((softc->state & TARG_STATE_LUN_ENABLED) != 0)
389 return (CAM_LUN_ALRDY_ENA);
390
391 /* Make sure SIM supports target mode */
392 xpt_path_inq(&cpi, path);
393 status = cpi.ccb_h.status & CAM_STATUS_MASK;
394 if (status != CAM_REQ_CMP) {
395 printf("pathinq failed, status %#x\n", status);
396 goto enable_fail;
397 }
398 if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
399 printf("controller does not support target mode\n");
400 status = CAM_FUNC_NOTAVAIL;
401 goto enable_fail;
402 }
403 if (cpi.maxio == 0)
404 softc->maxio = DFLTPHYS; /* traditional default */
405 else if (cpi.maxio > maxphys)
406 softc->maxio = maxphys; /* for safety */
407 else
408 softc->maxio = cpi.maxio; /* real value */
409
410 /* Destroy any periph on our path if it is disabled */
411 periph = cam_periph_find(path, "targ");
412 if (periph != NULL) {
413 struct targ_softc *del_softc;
414
415 del_softc = (struct targ_softc *)periph->softc;
416 if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
417 cam_periph_invalidate(del_softc->periph);
418 del_softc->periph = NULL;
419 } else {
420 printf("Requested path still in use by targ%d\n",
421 periph->unit_number);
422 status = CAM_LUN_ALRDY_ENA;
423 goto enable_fail;
424 }
425 }
426
427 /* Create a periph instance attached to this path */
428 status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
429 "targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
430 if (status != CAM_REQ_CMP) {
431 printf("cam_periph_alloc failed, status %#x\n", status);
432 goto enable_fail;
433 }
434
435 /* Ensure that the periph now exists. */
436 if (cam_periph_find(path, "targ") == NULL) {
437 panic("targenable: succeeded but no periph?");
438 /* NOTREACHED */
439 }
440
441 /* Send the enable lun message */
442 status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
443 if (status != CAM_REQ_CMP) {
444 printf("enable lun failed, status %#x\n", status);
445 goto enable_fail;
446 }
447 softc->state |= TARG_STATE_LUN_ENABLED;
448
449 enable_fail:
450 return (status);
451 }
452
453 /* Disable this softc's target instance if enabled */
454 static cam_status
targdisable(struct targ_softc * softc)455 targdisable(struct targ_softc *softc)
456 {
457 cam_status status;
458
459 if ((softc->state & TARG_STATE_LUN_ENABLED) == 0)
460 return (CAM_REQ_CMP);
461
462 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targdisable\n"));
463
464 /* Abort any ccbs pending on the controller */
465 abort_all_pending(softc);
466
467 /* Disable this lun */
468 status = targendislun(softc->path, /*enable*/0,
469 /*grp6_len*/0, /*grp7_len*/0);
470 if (status == CAM_REQ_CMP)
471 softc->state &= ~TARG_STATE_LUN_ENABLED;
472 else
473 printf("Disable lun failed, status %#x\n", status);
474
475 return (status);
476 }
477
478 /* Initialize a periph (called from cam_periph_alloc) */
479 static cam_status
targctor(struct cam_periph * periph,void * arg)480 targctor(struct cam_periph *periph, void *arg)
481 {
482 struct targ_softc *softc;
483
484 /* Store pointer to softc for periph-driven routines */
485 softc = (struct targ_softc *)arg;
486 periph->softc = softc;
487 softc->periph = periph;
488 softc->path = periph->path;
489 return (CAM_REQ_CMP);
490 }
491
492 static void
targdtor(struct cam_periph * periph)493 targdtor(struct cam_periph *periph)
494 {
495 struct targ_softc *softc;
496 struct ccb_hdr *ccb_h;
497 struct targ_cmd_descr *descr;
498
499 softc = (struct targ_softc *)periph->softc;
500
501 /*
502 * targdisable() aborts CCBs back to the user and leaves them
503 * on user_ccb_queue and abort_queue in case the user is still
504 * interested in them. We free them now.
505 */
506 while ((ccb_h = TAILQ_FIRST(&softc->user_ccb_queue)) != NULL) {
507 TAILQ_REMOVE(&softc->user_ccb_queue, ccb_h, periph_links.tqe);
508 targfreeccb(softc, (union ccb *)ccb_h);
509 }
510 while ((descr = TAILQ_FIRST(&softc->abort_queue)) != NULL) {
511 TAILQ_REMOVE(&softc->abort_queue, descr, tqe);
512 free(descr, M_TARG);
513 }
514
515 softc->periph = NULL;
516 softc->path = NULL;
517 periph->softc = NULL;
518 }
519
520 /* Receive CCBs from user mode proc and send them to the HBA */
521 static int
targwrite(struct cdev * dev,struct uio * uio,int ioflag)522 targwrite(struct cdev *dev, struct uio *uio, int ioflag)
523 {
524 union ccb *user_ccb;
525 struct targ_softc *softc;
526 struct targ_cmd_descr *descr;
527 int write_len, error;
528 int func_code, priority;
529
530 devfs_get_cdevpriv((void **)&softc);
531 write_len = error = 0;
532 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
533 ("write - uio_resid %zd\n", uio->uio_resid));
534 while (uio->uio_resid >= sizeof(user_ccb) && error == 0) {
535 union ccb *ccb;
536
537 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
538 if (error != 0) {
539 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
540 ("write - uiomove failed (%d)\n", error));
541 break;
542 }
543 priority = fuword32(&user_ccb->ccb_h.pinfo.priority);
544 if (priority == CAM_PRIORITY_NONE) {
545 error = EINVAL;
546 break;
547 }
548 func_code = fuword32(&user_ccb->ccb_h.func_code);
549 switch (func_code) {
550 case XPT_ACCEPT_TARGET_IO:
551 case XPT_IMMED_NOTIFY:
552 case XPT_IMMEDIATE_NOTIFY:
553 cam_periph_lock(softc->periph);
554 ccb = targgetccb(softc, func_code, priority);
555 descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
556 descr->user_ccb = user_ccb;
557 descr->func_code = func_code;
558 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
559 ("Sent ATIO/INOT (%p)\n", user_ccb));
560 xpt_action(ccb);
561 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
562 &ccb->ccb_h,
563 periph_links.tqe);
564 cam_periph_unlock(softc->periph);
565 break;
566 default:
567 cam_periph_lock(softc->periph);
568 if ((func_code & XPT_FC_QUEUED) != 0) {
569 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
570 ("Sending queued ccb %#x (%p)\n",
571 func_code, user_ccb));
572 descr = targgetdescr(softc);
573 descr->user_ccb = user_ccb;
574 descr->priority = priority;
575 descr->func_code = func_code;
576 TAILQ_INSERT_TAIL(&softc->work_queue,
577 descr, tqe);
578 xpt_schedule(softc->periph, priority);
579 } else {
580 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
581 ("Sending inline ccb %#x (%p)\n",
582 func_code, user_ccb));
583 ccb = targgetccb(softc, func_code, priority);
584 descr = (struct targ_cmd_descr *)
585 ccb->ccb_h.targ_descr;
586 descr->user_ccb = user_ccb;
587 descr->priority = priority;
588 descr->func_code = func_code;
589 if (targusermerge(softc, descr, ccb) != EFAULT)
590 targsendccb(softc, ccb, descr);
591 targreturnccb(softc, ccb);
592 }
593 cam_periph_unlock(softc->periph);
594 break;
595 }
596 write_len += sizeof(user_ccb);
597 }
598
599 /*
600 * If we've successfully taken in some amount of
601 * data, return success for that data first. If
602 * an error is persistent, it will be reported
603 * on the next write.
604 */
605 if (error != 0 && write_len == 0)
606 return (error);
607 if (write_len == 0 && uio->uio_resid != 0)
608 return (ENOSPC);
609 return (0);
610 }
611
612 /* Process requests (descrs) via the periph-supplied CCBs */
613 static void
targstart(struct cam_periph * periph,union ccb * start_ccb)614 targstart(struct cam_periph *periph, union ccb *start_ccb)
615 {
616 struct targ_softc *softc;
617 struct targ_cmd_descr *descr, *next_descr;
618 int error;
619
620 softc = (struct targ_softc *)periph->softc;
621 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
622
623 descr = TAILQ_FIRST(&softc->work_queue);
624 if (descr == NULL) {
625 xpt_release_ccb(start_ccb);
626 } else {
627 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
628 next_descr = TAILQ_FIRST(&softc->work_queue);
629
630 /* Initiate a transaction using the descr and supplied CCB */
631 error = targusermerge(softc, descr, start_ccb);
632 if (error == 0)
633 error = targsendccb(softc, start_ccb, descr);
634 if (error != 0) {
635 xpt_print(periph->path,
636 "targsendccb failed, err %d\n", error);
637 xpt_release_ccb(start_ccb);
638 (void)suword(&descr->user_ccb->ccb_h.status,
639 CAM_REQ_CMP_ERR);
640 TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
641 notify_user(softc);
642 }
643
644 /* If we have more work to do, stay scheduled */
645 if (next_descr != NULL)
646 xpt_schedule(periph, next_descr->priority);
647 }
648 }
649
650 static int
targusermerge(struct targ_softc * softc,struct targ_cmd_descr * descr,union ccb * ccb)651 targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
652 union ccb *ccb)
653 {
654 struct ccb_hdr *u_ccbh, *k_ccbh;
655 size_t ccb_len;
656 int error;
657
658 u_ccbh = &descr->user_ccb->ccb_h;
659 k_ccbh = &ccb->ccb_h;
660
661 /*
662 * There are some fields in the CCB header that need to be
663 * preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
664 */
665 xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
666 k_ccbh->retry_count = fuword32(&u_ccbh->retry_count);
667 k_ccbh->func_code = descr->func_code;
668 k_ccbh->flags = fuword32(&u_ccbh->flags);
669 k_ccbh->timeout = fuword32(&u_ccbh->timeout);
670 ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
671 error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
672 if (error != 0) {
673 k_ccbh->status = CAM_REQ_CMP_ERR;
674 return (error);
675 }
676
677 /* Translate usermode abort_ccb pointer to its kernel counterpart */
678 if (k_ccbh->func_code == XPT_ABORT) {
679 struct ccb_abort *cab;
680 struct ccb_hdr *ccb_h;
681
682 cab = (struct ccb_abort *)ccb;
683 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
684 periph_links.tqe) {
685 struct targ_cmd_descr *ab_descr;
686
687 ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
688 if (ab_descr->user_ccb == cab->abort_ccb) {
689 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
690 ("Changing abort for %p to %p\n",
691 cab->abort_ccb, ccb_h));
692 cab->abort_ccb = (union ccb *)ccb_h;
693 break;
694 }
695 }
696 /* CCB not found, set appropriate status */
697 if (ccb_h == NULL) {
698 k_ccbh->status = CAM_PATH_INVALID;
699 error = ESRCH;
700 }
701 }
702
703 return (error);
704 }
705
706 /* Build and send a kernel CCB formed from descr->user_ccb */
707 static int
targsendccb(struct targ_softc * softc,union ccb * ccb,struct targ_cmd_descr * descr)708 targsendccb(struct targ_softc *softc, union ccb *ccb,
709 struct targ_cmd_descr *descr)
710 {
711 struct cam_periph_map_info *mapinfo;
712 struct ccb_hdr *ccb_h;
713 int error;
714
715 ccb_h = &ccb->ccb_h;
716 mapinfo = &descr->mapinfo;
717 mapinfo->num_bufs_used = 0;
718
719 /*
720 * There's no way for the user to have a completion
721 * function, so we put our own completion function in here.
722 * We also stash in a reference to our descriptor so targreturnccb()
723 * can find our mapping info.
724 */
725 ccb_h->cbfcnp = targdone;
726 ccb_h->targ_descr = descr;
727
728 if ((ccb_h->func_code == XPT_CONT_TARGET_IO) ||
729 (ccb_h->func_code == XPT_DEV_MATCH)) {
730 error = cam_periph_mapmem(ccb, mapinfo, softc->maxio);
731
732 /*
733 * cam_periph_mapmem returned an error, we can't continue.
734 * Return the error to the user.
735 */
736 if (error) {
737 ccb_h->status = CAM_REQ_CMP_ERR;
738 mapinfo->num_bufs_used = 0;
739 return (error);
740 }
741 }
742
743 /*
744 * Once queued on the pending CCB list, this CCB will be protected
745 * by our error recovery handler.
746 */
747 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
748 if (XPT_FC_IS_QUEUED(ccb)) {
749 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
750 periph_links.tqe);
751 }
752 xpt_action(ccb);
753
754 return (0);
755 }
756
757 /* Completion routine for CCBs (called at splsoftcam) */
758 static void
targdone(struct cam_periph * periph,union ccb * done_ccb)759 targdone(struct cam_periph *periph, union ccb *done_ccb)
760 {
761 struct targ_softc *softc;
762
763 CAM_DEBUG(periph->path, CAM_DEBUG_PERIPH, ("targdone %p\n", done_ccb));
764 softc = (struct targ_softc *)periph->softc;
765 TAILQ_REMOVE(&softc->pending_ccb_queue, &done_ccb->ccb_h,
766 periph_links.tqe);
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 */
797 static int
targread(struct cdev * dev,struct uio * uio,int ioflag)798 targread(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 if (suword(&user_ccb->ccb_h.status, CAM_REQ_ABORTED) != 0) {
872 error = EFAULT;
873 goto read_fail;
874 }
875 cam_periph_unlock(softc->periph);
876 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
877 cam_periph_lock(softc->periph);
878 if (error != 0)
879 goto read_fail;
880 read_len += sizeof(user_ccb);
881
882 user_descr = TAILQ_FIRST(abort_queue);
883 }
884
885 /*
886 * If we've successfully read some amount of data, don't report an
887 * error. If the error is persistent, it will be reported on the
888 * next read().
889 */
890 if (read_len == 0 && uio->uio_resid != 0)
891 error = ENOSPC;
892
893 read_fail:
894 cam_periph_unlock(softc->periph);
895 return (error);
896 }
897
898 /* Copy completed ccb back to the user */
899 static int
targreturnccb(struct targ_softc * softc,union ccb * ccb)900 targreturnccb(struct targ_softc *softc, union ccb *ccb)
901 {
902 struct targ_cmd_descr *descr;
903 struct ccb_hdr *u_ccbh;
904 size_t ccb_len;
905 int error;
906
907 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
908 descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
909 u_ccbh = &descr->user_ccb->ccb_h;
910
911 /* Copy out the central portion of the ccb_hdr */
912 error = copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
913 offsetof(struct ccb_hdr, periph_priv) -
914 offsetof(struct ccb_hdr, retry_count));
915 if (error != 0) {
916 xpt_print(softc->path,
917 "targreturnccb - CCB header copyout failed (%d)\n", error);
918 }
919
920 /* Copy out the rest of the ccb (after the ccb_hdr) */
921 ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
922 if (descr->mapinfo.num_bufs_used != 0) {
923 int error1;
924
925 error1 = cam_periph_unmapmem(ccb, &descr->mapinfo);
926 if (error == 0)
927 error = error1;
928 }
929 if (error == 0) {
930 error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
931 if (error != 0) {
932 xpt_print(softc->path,
933 "targreturnccb - CCB copyout failed (%d)\n", error);
934 }
935 }
936 /* Free CCB or send back to devq. */
937 targfreeccb(softc, ccb);
938
939 return (error);
940 }
941
942 static union ccb *
targgetccb(struct targ_softc * softc,xpt_opcode type,int priority)943 targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
944 {
945 union ccb *ccb;
946 int ccb_len;
947
948 ccb_len = targccblen(type);
949 ccb = malloc(ccb_len, M_TARG, M_NOWAIT | M_ZERO);
950 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
951 if (ccb == NULL) {
952 return (ccb);
953 }
954 xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
955 ccb->ccb_h.func_code = type;
956 ccb->ccb_h.cbfcnp = targdone;
957 ccb->ccb_h.targ_descr = targgetdescr(softc);
958 if (ccb->ccb_h.targ_descr == NULL) {
959 free (ccb, M_TARG);
960 ccb = NULL;
961 }
962 return (ccb);
963 }
964
965 static void
targfreeccb(struct targ_softc * softc,union ccb * ccb)966 targfreeccb(struct targ_softc *softc, union ccb *ccb)
967 {
968 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
969 ccb->ccb_h.targ_descr));
970 free(ccb->ccb_h.targ_descr, M_TARG);
971
972 switch (ccb->ccb_h.func_code) {
973 case XPT_ACCEPT_TARGET_IO:
974 case XPT_IMMED_NOTIFY:
975 case XPT_IMMEDIATE_NOTIFY:
976 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
977 free(ccb, M_TARG);
978 break;
979 default:
980 /* Send back CCB if we got it from the periph */
981 if (XPT_FC_IS_QUEUED(ccb)) {
982 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
983 ("returning queued ccb %p\n", ccb));
984 xpt_release_ccb(ccb);
985 } else {
986 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
987 ("freeing ccb %p\n", ccb));
988 free(ccb, M_TARG);
989 }
990 break;
991 }
992 }
993
994 static struct targ_cmd_descr *
targgetdescr(struct targ_softc * softc)995 targgetdescr(struct targ_softc *softc)
996 {
997 struct targ_cmd_descr *descr;
998
999 descr = malloc(sizeof(*descr), M_TARG,
1000 M_NOWAIT);
1001 if (descr) {
1002 descr->mapinfo.num_bufs_used = 0;
1003 }
1004 return (descr);
1005 }
1006
1007 static void
targinit(void)1008 targinit(void)
1009 {
1010 struct cdev *dev;
1011
1012 /* Add symbolic link to targ0 for compatibility. */
1013 dev = make_dev(&targ_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "targ");
1014 make_dev_alias(dev, "targ0");
1015 }
1016
1017 static void
targasync(void * callback_arg,uint32_t code,struct cam_path * path,void * arg)1018 targasync(void *callback_arg, uint32_t code, struct cam_path *path, void *arg)
1019 {
1020 /* All events are handled in usermode by INOTs */
1021 panic("targasync() called, should be an INOT instead");
1022 }
1023
1024 /* Cancel all pending requests and CCBs awaiting work. */
1025 static void
abort_all_pending(struct targ_softc * softc)1026 abort_all_pending(struct targ_softc *softc)
1027 {
1028 struct targ_cmd_descr *descr;
1029 struct ccb_abort cab;
1030 struct ccb_hdr *ccb_h;
1031
1032 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("abort_all_pending\n"));
1033
1034 /* First abort the descriptors awaiting resources */
1035 while ((descr = TAILQ_FIRST(&softc->work_queue)) != NULL) {
1036 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1037 ("Aborting descr from workq %p\n", descr));
1038 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
1039 TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
1040 }
1041
1042 /*
1043 * Then abort all pending CCBs.
1044 * targdone() will return the aborted CCB via user_ccb_queue
1045 */
1046 memset(&cab, 0, sizeof(cab));
1047 xpt_setup_ccb(&cab.ccb_h, softc->path, CAM_PRIORITY_NORMAL);
1048 cab.ccb_h.func_code = XPT_ABORT;
1049 cab.ccb_h.status = CAM_REQ_CMP_ERR;
1050 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue, periph_links.tqe) {
1051 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1052 ("Aborting pending CCB %p\n", ccb_h));
1053 cab.abort_ccb = (union ccb *)ccb_h;
1054 xpt_action((union ccb *)&cab);
1055 if (cab.ccb_h.status != CAM_REQ_CMP) {
1056 xpt_print(cab.ccb_h.path,
1057 "Unable to abort CCB, status %#x\n",
1058 cab.ccb_h.status);
1059 }
1060 }
1061
1062 /* If we aborted at least one pending CCB ok, wait for it. */
1063 if (cab.ccb_h.status == CAM_REQ_CMP) {
1064 cam_periph_sleep(softc->periph, &softc->pending_ccb_queue,
1065 PRIBIO | PCATCH, "tgabrt", 0);
1066 }
1067
1068 /* If we aborted anything from the work queue, wakeup user. */
1069 if (!TAILQ_EMPTY(&softc->user_ccb_queue)
1070 || !TAILQ_EMPTY(&softc->abort_queue)) {
1071 cam_periph_unlock(softc->periph);
1072 notify_user(softc);
1073 cam_periph_lock(softc->periph);
1074 }
1075 }
1076
1077 /* Notify the user that data is ready */
1078 static void
notify_user(struct targ_softc * softc)1079 notify_user(struct targ_softc *softc)
1080 {
1081 /*
1082 * Notify users sleeping via poll(), kqueue(), and
1083 * blocking read().
1084 */
1085 selwakeuppri(&softc->read_select, PRIBIO);
1086 KNOTE_UNLOCKED(&softc->read_select.si_note, 0);
1087 wakeup(&softc->user_ccb_queue);
1088 }
1089
1090 /* Convert CAM status to errno values */
1091 static int
targcamstatus(cam_status status)1092 targcamstatus(cam_status status)
1093 {
1094 switch (status & CAM_STATUS_MASK) {
1095 case CAM_REQ_CMP: /* CCB request completed without error */
1096 return (0);
1097 case CAM_REQ_INPROG: /* CCB request is in progress */
1098 return (EINPROGRESS);
1099 case CAM_REQ_CMP_ERR: /* CCB request completed with an error */
1100 return (EIO);
1101 case CAM_PROVIDE_FAIL: /* Unable to provide requested capability */
1102 return (ENOTTY);
1103 case CAM_FUNC_NOTAVAIL: /* The requested function is not available */
1104 return (ENOTSUP);
1105 case CAM_LUN_ALRDY_ENA: /* LUN is already enabled for target mode */
1106 return (EADDRINUSE);
1107 case CAM_PATH_INVALID: /* Supplied Path ID is invalid */
1108 case CAM_DEV_NOT_THERE: /* SCSI Device Not Installed/there */
1109 return (ENOENT);
1110 case CAM_REQ_ABORTED: /* CCB request aborted by the host */
1111 return (ECANCELED);
1112 case CAM_CMD_TIMEOUT: /* Command timeout */
1113 return (ETIMEDOUT);
1114 case CAM_REQUEUE_REQ: /* Requeue to preserve transaction ordering */
1115 return (EAGAIN);
1116 case CAM_REQ_INVALID: /* CCB request was invalid */
1117 return (EINVAL);
1118 case CAM_RESRC_UNAVAIL: /* Resource Unavailable */
1119 return (ENOMEM);
1120 case CAM_BUSY: /* CAM subsystem is busy */
1121 case CAM_UA_ABORT: /* Unable to abort CCB request */
1122 return (EBUSY);
1123 default:
1124 return (ENXIO);
1125 }
1126 }
1127
1128 static size_t
targccblen(xpt_opcode func_code)1129 targccblen(xpt_opcode func_code)
1130 {
1131 int len;
1132
1133 /* Codes we expect to see as a target */
1134 switch (func_code) {
1135 case XPT_CONT_TARGET_IO:
1136 case XPT_SCSI_IO:
1137 len = sizeof(struct ccb_scsiio);
1138 break;
1139 case XPT_ACCEPT_TARGET_IO:
1140 len = sizeof(struct ccb_accept_tio);
1141 break;
1142 case XPT_IMMED_NOTIFY:
1143 len = sizeof(struct ccb_immed_notify);
1144 break;
1145 case XPT_IMMEDIATE_NOTIFY:
1146 len = sizeof(struct ccb_immediate_notify);
1147 break;
1148 case XPT_REL_SIMQ:
1149 len = sizeof(struct ccb_relsim);
1150 break;
1151 case XPT_PATH_INQ:
1152 len = sizeof(struct ccb_pathinq);
1153 break;
1154 case XPT_DEBUG:
1155 len = sizeof(struct ccb_debug);
1156 break;
1157 case XPT_ABORT:
1158 len = sizeof(struct ccb_abort);
1159 break;
1160 case XPT_EN_LUN:
1161 len = sizeof(struct ccb_en_lun);
1162 break;
1163 default:
1164 len = sizeof(union ccb);
1165 break;
1166 }
1167
1168 return (len);
1169 }
1170