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 };
112
113 static struct cdevsw targ_cdevsw = {
114 .d_version = D_VERSION,
115 .d_open = targopen,
116 .d_read = targread,
117 .d_write = targwrite,
118 .d_ioctl = targioctl,
119 .d_poll = targpoll,
120 .d_name = "targ",
121 .d_kqfilter = targkqfilter
122 };
123
124 static cam_status targendislun(struct cam_path *path, int enable,
125 int grp6_len, int grp7_len);
126 static cam_status targenable(struct targ_softc *softc,
127 struct cam_path *path,
128 int grp6_len, int grp7_len);
129 static cam_status targdisable(struct targ_softc *softc);
130 static periph_ctor_t targctor;
131 static periph_dtor_t targdtor;
132 static periph_start_t targstart;
133 static int targusermerge(struct targ_softc *softc,
134 struct targ_cmd_descr *descr,
135 union ccb *ccb);
136 static int targsendccb(struct targ_softc *softc, union ccb *ccb,
137 struct targ_cmd_descr *descr);
138 static void targdone(struct cam_periph *periph,
139 union ccb *done_ccb);
140 static int targreturnccb(struct targ_softc *softc,
141 union ccb *ccb);
142 static union ccb * targgetccb(struct targ_softc *softc, xpt_opcode type,
143 int priority);
144 static void targfreeccb(struct targ_softc *softc, union ccb *ccb);
145 static struct targ_cmd_descr *
146 targgetdescr(struct targ_softc *softc);
147 static periph_init_t targinit;
148 static void targasync(void *callback_arg, uint32_t code,
149 struct cam_path *path, void *arg);
150 static void abort_all_pending(struct targ_softc *softc);
151 static void notify_user(struct targ_softc *softc);
152 static int targcamstatus(cam_status status);
153 static size_t targccblen(xpt_opcode func_code);
154
155 static struct periph_driver targdriver =
156 {
157 targinit, "targ",
158 TAILQ_HEAD_INITIALIZER(targdriver.units), /* generation */ 0
159 };
160 PERIPHDRIVER_DECLARE(targ, targdriver);
161
162 static MALLOC_DEFINE(M_TARG, "TARG", "TARG data");
163
164 /* Disable LUN if enabled and teardown softc */
165 static void
targcdevdtor(void * data)166 targcdevdtor(void *data)
167 {
168 struct targ_softc *softc;
169 struct cam_periph *periph;
170
171 softc = data;
172 if (softc->periph == NULL) {
173 printf("%s: destroying non-enabled target\n", __func__);
174 free(softc, M_TARG);
175 return;
176 }
177
178 /*
179 * Acquire a hold on the periph so that it doesn't go away before
180 * we are ready at the end of the function.
181 */
182 periph = softc->periph;
183 cam_periph_acquire(periph);
184 cam_periph_lock(periph);
185 (void)targdisable(softc);
186 if (softc->periph != NULL) {
187 cam_periph_invalidate(softc->periph);
188 softc->periph = NULL;
189 }
190 cam_periph_unlock(periph);
191 cam_periph_release(periph);
192 free(softc, M_TARG);
193 }
194
195 /*
196 * Create softc and initialize it. There is no locking here because a
197 * periph doesn't get created until an ioctl is issued to do so, and
198 * that can't happen until this method returns.
199 */
200 static int
targopen(struct cdev * dev,int flags,int fmt,struct thread * td)201 targopen(struct cdev *dev, int flags, int fmt, struct thread *td)
202 {
203 struct targ_softc *softc;
204
205 /* Allocate its softc, initialize it */
206 softc = malloc(sizeof(*softc), M_TARG,
207 M_WAITOK | M_ZERO);
208 softc->state = TARG_STATE_OPENED;
209 softc->periph = NULL;
210 softc->path = NULL;
211
212 TAILQ_INIT(&softc->pending_ccb_queue);
213 TAILQ_INIT(&softc->work_queue);
214 TAILQ_INIT(&softc->abort_queue);
215 TAILQ_INIT(&softc->user_ccb_queue);
216 knlist_init_mtx(&softc->read_select.si_note, NULL);
217
218 devfs_set_cdevpriv(softc, targcdevdtor);
219 return (0);
220 }
221
222 /* Enable/disable LUNs, set debugging level */
223 static int
targioctl(struct cdev * dev,u_long cmd,caddr_t addr,int flag,struct thread * td)224 targioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
225 {
226 struct targ_softc *softc;
227 cam_status status;
228
229 devfs_get_cdevpriv((void **)&softc);
230
231 switch (cmd) {
232 case TARGIOCENABLE:
233 {
234 struct ioc_enable_lun *new_lun;
235 struct cam_path *path;
236
237 new_lun = (struct ioc_enable_lun *)addr;
238 status = xpt_create_path(&path, /*periph*/NULL,
239 new_lun->path_id,
240 new_lun->target_id,
241 new_lun->lun_id);
242 if (status != CAM_REQ_CMP) {
243 printf("Couldn't create path, status %#x\n", status);
244 break;
245 }
246 xpt_path_lock(path);
247 status = targenable(softc, path, new_lun->grp6_len,
248 new_lun->grp7_len);
249 xpt_path_unlock(path);
250 xpt_free_path(path);
251 break;
252 }
253 case TARGIOCDISABLE:
254 if (softc->periph == NULL) {
255 status = CAM_DEV_NOT_THERE;
256 break;
257 }
258 cam_periph_lock(softc->periph);
259 status = targdisable(softc);
260 cam_periph_unlock(softc->periph);
261 break;
262 case TARGIOCDEBUG:
263 {
264 struct ccb_debug cdbg;
265
266 /* If no periph available, disallow debugging changes */
267 if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
268 status = CAM_DEV_NOT_THERE;
269 break;
270 }
271 bzero(&cdbg, sizeof cdbg);
272 if (*((int *)addr) != 0)
273 cdbg.flags = CAM_DEBUG_PERIPH;
274 else
275 cdbg.flags = CAM_DEBUG_NONE;
276 xpt_setup_ccb(&cdbg.ccb_h, softc->path, CAM_PRIORITY_NORMAL);
277 cdbg.ccb_h.func_code = XPT_DEBUG;
278 cdbg.ccb_h.cbfcnp = targdone;
279 xpt_action((union ccb *)&cdbg);
280 status = cdbg.ccb_h.status & CAM_STATUS_MASK;
281 break;
282 }
283 default:
284 status = CAM_PROVIDE_FAIL;
285 break;
286 }
287
288 return (targcamstatus(status));
289 }
290
291 /* Writes are always ready, reads wait for user_ccb_queue or abort_queue */
292 static int
targpoll(struct cdev * dev,int poll_events,struct thread * td)293 targpoll(struct cdev *dev, int poll_events, struct thread *td)
294 {
295 struct targ_softc *softc;
296 int revents;
297
298 devfs_get_cdevpriv((void **)&softc);
299
300 /* Poll for write() is always ok. */
301 revents = poll_events & (POLLOUT | POLLWRNORM);
302 if ((poll_events & (POLLIN | POLLRDNORM)) != 0) {
303 /* Poll for read() depends on user and abort queues. */
304 cam_periph_lock(softc->periph);
305 if (!TAILQ_EMPTY(&softc->user_ccb_queue) ||
306 !TAILQ_EMPTY(&softc->abort_queue)) {
307 revents |= poll_events & (POLLIN | POLLRDNORM);
308 }
309 cam_periph_unlock(softc->periph);
310 /* Only sleep if the user didn't poll for write. */
311 if (revents == 0)
312 selrecord(td, &softc->read_select);
313 }
314
315 return (revents);
316 }
317
318 static int
targkqfilter(struct cdev * dev,struct knote * kn)319 targkqfilter(struct cdev *dev, struct knote *kn)
320 {
321 struct targ_softc *softc;
322
323 devfs_get_cdevpriv((void **)&softc);
324 kn->kn_hook = (caddr_t)softc;
325 kn->kn_fop = &targread_filtops;
326 knlist_add(&softc->read_select.si_note, kn, 0);
327 return (0);
328 }
329
330 static void
targreadfiltdetach(struct knote * kn)331 targreadfiltdetach(struct knote *kn)
332 {
333 struct targ_softc *softc;
334
335 softc = (struct targ_softc *)kn->kn_hook;
336 knlist_remove(&softc->read_select.si_note, kn, 0);
337 }
338
339 /* Notify the user's kqueue when the user queue or abort queue gets a CCB */
340 static int
targreadfilt(struct knote * kn,long hint)341 targreadfilt(struct knote *kn, long hint)
342 {
343 struct targ_softc *softc;
344 int retval;
345
346 softc = (struct targ_softc *)kn->kn_hook;
347 cam_periph_lock(softc->periph);
348 retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
349 !TAILQ_EMPTY(&softc->abort_queue);
350 cam_periph_unlock(softc->periph);
351 return (retval);
352 }
353
354 /* Send the HBA the enable/disable message */
355 static cam_status
targendislun(struct cam_path * path,int enable,int grp6_len,int grp7_len)356 targendislun(struct cam_path *path, int enable, int grp6_len, int grp7_len)
357 {
358 struct ccb_en_lun en_ccb;
359 cam_status status;
360
361 /* Tell the lun to begin answering selects */
362 memset(&en_ccb, 0, sizeof(en_ccb));
363 xpt_setup_ccb(&en_ccb.ccb_h, path, CAM_PRIORITY_NORMAL);
364 en_ccb.ccb_h.func_code = XPT_EN_LUN;
365 /* Don't need support for any vendor specific commands */
366 en_ccb.grp6_len = grp6_len;
367 en_ccb.grp7_len = grp7_len;
368 en_ccb.enable = enable ? 1 : 0;
369 xpt_action((union ccb *)&en_ccb);
370 status = en_ccb.ccb_h.status & CAM_STATUS_MASK;
371 if (status != CAM_REQ_CMP) {
372 xpt_print(path, "%sable lun CCB rejected, status %#x\n",
373 enable ? "en" : "dis", status);
374 }
375 return (status);
376 }
377
378 /* Enable target mode on a LUN, given its path */
379 static cam_status
targenable(struct targ_softc * softc,struct cam_path * path,int grp6_len,int grp7_len)380 targenable(struct targ_softc *softc, struct cam_path *path, int grp6_len,
381 int grp7_len)
382 {
383 struct cam_periph *periph;
384 struct ccb_pathinq cpi;
385 cam_status status;
386
387 if ((softc->state & TARG_STATE_LUN_ENABLED) != 0)
388 return (CAM_LUN_ALRDY_ENA);
389
390 /* Make sure SIM supports target mode */
391 xpt_path_inq(&cpi, path);
392 status = cpi.ccb_h.status & CAM_STATUS_MASK;
393 if (status != CAM_REQ_CMP) {
394 printf("pathinq failed, status %#x\n", status);
395 goto enable_fail;
396 }
397 if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
398 printf("controller does not support target mode\n");
399 status = CAM_FUNC_NOTAVAIL;
400 goto enable_fail;
401 }
402 if (cpi.maxio == 0)
403 softc->maxio = DFLTPHYS; /* traditional default */
404 else if (cpi.maxio > maxphys)
405 softc->maxio = maxphys; /* for safety */
406 else
407 softc->maxio = cpi.maxio; /* real value */
408
409 /* Destroy any periph on our path if it is disabled */
410 periph = cam_periph_find(path, "targ");
411 if (periph != NULL) {
412 struct targ_softc *del_softc;
413
414 del_softc = (struct targ_softc *)periph->softc;
415 if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
416 cam_periph_invalidate(del_softc->periph);
417 del_softc->periph = NULL;
418 } else {
419 printf("Requested path still in use by targ%d\n",
420 periph->unit_number);
421 status = CAM_LUN_ALRDY_ENA;
422 goto enable_fail;
423 }
424 }
425
426 /* Create a periph instance attached to this path */
427 status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
428 "targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
429 if (status != CAM_REQ_CMP) {
430 printf("cam_periph_alloc failed, status %#x\n", status);
431 goto enable_fail;
432 }
433
434 /* Ensure that the periph now exists. */
435 if (cam_periph_find(path, "targ") == NULL) {
436 panic("targenable: succeeded but no periph?");
437 /* NOTREACHED */
438 }
439
440 /* Send the enable lun message */
441 status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
442 if (status != CAM_REQ_CMP) {
443 printf("enable lun failed, status %#x\n", status);
444 goto enable_fail;
445 }
446 softc->state |= TARG_STATE_LUN_ENABLED;
447
448 enable_fail:
449 return (status);
450 }
451
452 /* Disable this softc's target instance if enabled */
453 static cam_status
targdisable(struct targ_softc * softc)454 targdisable(struct targ_softc *softc)
455 {
456 cam_status status;
457
458 if ((softc->state & TARG_STATE_LUN_ENABLED) == 0)
459 return (CAM_REQ_CMP);
460
461 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targdisable\n"));
462
463 /* Abort any ccbs pending on the controller */
464 abort_all_pending(softc);
465
466 /* Disable this lun */
467 status = targendislun(softc->path, /*enable*/0,
468 /*grp6_len*/0, /*grp7_len*/0);
469 if (status == CAM_REQ_CMP)
470 softc->state &= ~TARG_STATE_LUN_ENABLED;
471 else
472 printf("Disable lun failed, status %#x\n", status);
473
474 return (status);
475 }
476
477 /* Initialize a periph (called from cam_periph_alloc) */
478 static cam_status
targctor(struct cam_periph * periph,void * arg)479 targctor(struct cam_periph *periph, void *arg)
480 {
481 struct targ_softc *softc;
482
483 /* Store pointer to softc for periph-driven routines */
484 softc = (struct targ_softc *)arg;
485 periph->softc = softc;
486 softc->periph = periph;
487 softc->path = periph->path;
488 return (CAM_REQ_CMP);
489 }
490
491 static void
targdtor(struct cam_periph * periph)492 targdtor(struct cam_periph *periph)
493 {
494 struct targ_softc *softc;
495 struct ccb_hdr *ccb_h;
496 struct targ_cmd_descr *descr;
497
498 softc = (struct targ_softc *)periph->softc;
499
500 /*
501 * targdisable() aborts CCBs back to the user and leaves them
502 * on user_ccb_queue and abort_queue in case the user is still
503 * interested in them. We free them now.
504 */
505 while ((ccb_h = TAILQ_FIRST(&softc->user_ccb_queue)) != NULL) {
506 TAILQ_REMOVE(&softc->user_ccb_queue, ccb_h, periph_links.tqe);
507 targfreeccb(softc, (union ccb *)ccb_h);
508 }
509 while ((descr = TAILQ_FIRST(&softc->abort_queue)) != NULL) {
510 TAILQ_REMOVE(&softc->abort_queue, descr, tqe);
511 free(descr, M_TARG);
512 }
513
514 softc->periph = NULL;
515 softc->path = NULL;
516 periph->softc = NULL;
517 }
518
519 /* Receive CCBs from user mode proc and send them to the HBA */
520 static int
targwrite(struct cdev * dev,struct uio * uio,int ioflag)521 targwrite(struct cdev *dev, struct uio *uio, int ioflag)
522 {
523 union ccb *user_ccb;
524 struct targ_softc *softc;
525 struct targ_cmd_descr *descr;
526 int write_len, error;
527 int func_code, priority;
528
529 devfs_get_cdevpriv((void **)&softc);
530 write_len = error = 0;
531 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
532 ("write - uio_resid %zd\n", uio->uio_resid));
533 while (uio->uio_resid >= sizeof(user_ccb) && error == 0) {
534 union ccb *ccb;
535
536 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
537 if (error != 0) {
538 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
539 ("write - uiomove failed (%d)\n", error));
540 break;
541 }
542 priority = fuword32(&user_ccb->ccb_h.pinfo.priority);
543 if (priority == CAM_PRIORITY_NONE) {
544 error = EINVAL;
545 break;
546 }
547 func_code = fuword32(&user_ccb->ccb_h.func_code);
548 switch (func_code) {
549 case XPT_ACCEPT_TARGET_IO:
550 case XPT_IMMED_NOTIFY:
551 case XPT_IMMEDIATE_NOTIFY:
552 cam_periph_lock(softc->periph);
553 ccb = targgetccb(softc, func_code, priority);
554 descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
555 descr->user_ccb = user_ccb;
556 descr->func_code = func_code;
557 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
558 ("Sent ATIO/INOT (%p)\n", user_ccb));
559 xpt_action(ccb);
560 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
561 &ccb->ccb_h,
562 periph_links.tqe);
563 cam_periph_unlock(softc->periph);
564 break;
565 default:
566 cam_periph_lock(softc->periph);
567 if ((func_code & XPT_FC_QUEUED) != 0) {
568 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
569 ("Sending queued ccb %#x (%p)\n",
570 func_code, user_ccb));
571 descr = targgetdescr(softc);
572 descr->user_ccb = user_ccb;
573 descr->priority = priority;
574 descr->func_code = func_code;
575 TAILQ_INSERT_TAIL(&softc->work_queue,
576 descr, tqe);
577 xpt_schedule(softc->periph, priority);
578 } else {
579 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
580 ("Sending inline ccb %#x (%p)\n",
581 func_code, user_ccb));
582 ccb = targgetccb(softc, func_code, priority);
583 descr = (struct targ_cmd_descr *)
584 ccb->ccb_h.targ_descr;
585 descr->user_ccb = user_ccb;
586 descr->priority = priority;
587 descr->func_code = func_code;
588 if (targusermerge(softc, descr, ccb) != EFAULT)
589 targsendccb(softc, ccb, descr);
590 targreturnccb(softc, ccb);
591 }
592 cam_periph_unlock(softc->periph);
593 break;
594 }
595 write_len += sizeof(user_ccb);
596 }
597
598 /*
599 * If we've successfully taken in some amount of
600 * data, return success for that data first. If
601 * an error is persistent, it will be reported
602 * on the next write.
603 */
604 if (error != 0 && write_len == 0)
605 return (error);
606 if (write_len == 0 && uio->uio_resid != 0)
607 return (ENOSPC);
608 return (0);
609 }
610
611 /* Process requests (descrs) via the periph-supplied CCBs */
612 static void
targstart(struct cam_periph * periph,union ccb * start_ccb)613 targstart(struct cam_periph *periph, union ccb *start_ccb)
614 {
615 struct targ_softc *softc;
616 struct targ_cmd_descr *descr, *next_descr;
617 int error;
618
619 softc = (struct targ_softc *)periph->softc;
620 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
621
622 descr = TAILQ_FIRST(&softc->work_queue);
623 if (descr == NULL) {
624 xpt_release_ccb(start_ccb);
625 } else {
626 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
627 next_descr = TAILQ_FIRST(&softc->work_queue);
628
629 /* Initiate a transaction using the descr and supplied CCB */
630 error = targusermerge(softc, descr, start_ccb);
631 if (error == 0)
632 error = targsendccb(softc, start_ccb, descr);
633 if (error != 0) {
634 xpt_print(periph->path,
635 "targsendccb failed, err %d\n", error);
636 xpt_release_ccb(start_ccb);
637 (void)suword(&descr->user_ccb->ccb_h.status,
638 CAM_REQ_CMP_ERR);
639 TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
640 notify_user(softc);
641 }
642
643 /* If we have more work to do, stay scheduled */
644 if (next_descr != NULL)
645 xpt_schedule(periph, next_descr->priority);
646 }
647 }
648
649 static int
targusermerge(struct targ_softc * softc,struct targ_cmd_descr * descr,union ccb * ccb)650 targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
651 union ccb *ccb)
652 {
653 struct ccb_hdr *u_ccbh, *k_ccbh;
654 size_t ccb_len;
655 int error;
656
657 u_ccbh = &descr->user_ccb->ccb_h;
658 k_ccbh = &ccb->ccb_h;
659
660 /*
661 * There are some fields in the CCB header that need to be
662 * preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
663 */
664 xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
665 k_ccbh->retry_count = fuword32(&u_ccbh->retry_count);
666 k_ccbh->func_code = descr->func_code;
667 k_ccbh->flags = fuword32(&u_ccbh->flags);
668 k_ccbh->timeout = fuword32(&u_ccbh->timeout);
669 ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
670 error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
671 if (error != 0) {
672 k_ccbh->status = CAM_REQ_CMP_ERR;
673 return (error);
674 }
675
676 /* Translate usermode abort_ccb pointer to its kernel counterpart */
677 if (k_ccbh->func_code == XPT_ABORT) {
678 struct ccb_abort *cab;
679 struct ccb_hdr *ccb_h;
680
681 cab = (struct ccb_abort *)ccb;
682 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
683 periph_links.tqe) {
684 struct targ_cmd_descr *ab_descr;
685
686 ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
687 if (ab_descr->user_ccb == cab->abort_ccb) {
688 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
689 ("Changing abort for %p to %p\n",
690 cab->abort_ccb, ccb_h));
691 cab->abort_ccb = (union ccb *)ccb_h;
692 break;
693 }
694 }
695 /* CCB not found, set appropriate status */
696 if (ccb_h == NULL) {
697 k_ccbh->status = CAM_PATH_INVALID;
698 error = ESRCH;
699 }
700 }
701
702 return (error);
703 }
704
705 /* Build and send a kernel CCB formed from descr->user_ccb */
706 static int
targsendccb(struct targ_softc * softc,union ccb * ccb,struct targ_cmd_descr * descr)707 targsendccb(struct targ_softc *softc, union ccb *ccb,
708 struct targ_cmd_descr *descr)
709 {
710 struct cam_periph_map_info *mapinfo;
711 struct ccb_hdr *ccb_h;
712 int error;
713
714 ccb_h = &ccb->ccb_h;
715 mapinfo = &descr->mapinfo;
716 mapinfo->num_bufs_used = 0;
717
718 /*
719 * There's no way for the user to have a completion
720 * function, so we put our own completion function in here.
721 * We also stash in a reference to our descriptor so targreturnccb()
722 * can find our mapping info.
723 */
724 ccb_h->cbfcnp = targdone;
725 ccb_h->targ_descr = descr;
726
727 if ((ccb_h->func_code == XPT_CONT_TARGET_IO) ||
728 (ccb_h->func_code == XPT_DEV_MATCH)) {
729 error = cam_periph_mapmem(ccb, mapinfo, softc->maxio);
730
731 /*
732 * cam_periph_mapmem returned an error, we can't continue.
733 * Return the error to the user.
734 */
735 if (error) {
736 ccb_h->status = CAM_REQ_CMP_ERR;
737 mapinfo->num_bufs_used = 0;
738 return (error);
739 }
740 }
741
742 /*
743 * Once queued on the pending CCB list, this CCB will be protected
744 * by our error recovery handler.
745 */
746 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
747 if (XPT_FC_IS_QUEUED(ccb)) {
748 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
749 periph_links.tqe);
750 }
751 xpt_action(ccb);
752
753 return (0);
754 }
755
756 /* Completion routine for CCBs (called at splsoftcam) */
757 static void
targdone(struct cam_periph * periph,union ccb * done_ccb)758 targdone(struct cam_periph *periph, union ccb *done_ccb)
759 {
760 struct targ_softc *softc;
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
767 /* If we're no longer enabled, throw away CCB */
768 if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
769 targfreeccb(softc, done_ccb);
770 return;
771 }
772 /* abort_all_pending() waits for pending queue to be empty */
773 if (TAILQ_EMPTY(&softc->pending_ccb_queue))
774 wakeup(&softc->pending_ccb_queue);
775
776 switch (done_ccb->ccb_h.func_code) {
777 /* All FC_*_QUEUED CCBs go back to userland */
778 case XPT_IMMED_NOTIFY:
779 case XPT_IMMEDIATE_NOTIFY:
780 case XPT_ACCEPT_TARGET_IO:
781 case XPT_CONT_TARGET_IO:
782 TAILQ_INSERT_TAIL(&softc->user_ccb_queue, &done_ccb->ccb_h,
783 periph_links.tqe);
784 cam_periph_unlock(softc->periph);
785 notify_user(softc);
786 cam_periph_lock(softc->periph);
787 break;
788 default:
789 panic("targdone: impossible xpt opcode %#x",
790 done_ccb->ccb_h.func_code);
791 /* NOTREACHED */
792 }
793 }
794
795 /* Return CCBs to the user from the user queue and abort queue */
796 static int
targread(struct cdev * dev,struct uio * uio,int ioflag)797 targread(struct cdev *dev, struct uio *uio, int ioflag)
798 {
799 struct descr_queue *abort_queue;
800 struct targ_cmd_descr *user_descr;
801 struct targ_softc *softc;
802 struct ccb_queue *user_queue;
803 struct ccb_hdr *ccb_h;
804 union ccb *user_ccb;
805 int read_len, error;
806
807 error = 0;
808 read_len = 0;
809 devfs_get_cdevpriv((void **)&softc);
810 user_queue = &softc->user_ccb_queue;
811 abort_queue = &softc->abort_queue;
812 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targread\n"));
813
814 /* If no data is available, wait or return immediately */
815 cam_periph_lock(softc->periph);
816 ccb_h = TAILQ_FIRST(user_queue);
817 user_descr = TAILQ_FIRST(abort_queue);
818 while (ccb_h == NULL && user_descr == NULL) {
819 if ((ioflag & IO_NDELAY) == 0) {
820 error = cam_periph_sleep(softc->periph, user_queue,
821 PRIBIO | PCATCH, "targrd", 0);
822 ccb_h = TAILQ_FIRST(user_queue);
823 user_descr = TAILQ_FIRST(abort_queue);
824 if (error != 0) {
825 if (error == ERESTART) {
826 continue;
827 } else {
828 goto read_fail;
829 }
830 }
831 } else {
832 cam_periph_unlock(softc->periph);
833 return (EAGAIN);
834 }
835 }
836
837 /* Data is available so fill the user's buffer */
838 while (ccb_h != NULL) {
839 struct targ_cmd_descr *descr;
840
841 if (uio->uio_resid < sizeof(user_ccb))
842 break;
843 TAILQ_REMOVE(user_queue, ccb_h, periph_links.tqe);
844 descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
845 user_ccb = descr->user_ccb;
846 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
847 ("targread ccb %p (%p)\n", ccb_h, user_ccb));
848 error = targreturnccb(softc, (union ccb *)ccb_h);
849 if (error != 0)
850 goto read_fail;
851 cam_periph_unlock(softc->periph);
852 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
853 cam_periph_lock(softc->periph);
854 if (error != 0)
855 goto read_fail;
856 read_len += sizeof(user_ccb);
857
858 ccb_h = TAILQ_FIRST(user_queue);
859 }
860
861 /* Flush out any aborted descriptors */
862 while (user_descr != NULL) {
863 if (uio->uio_resid < sizeof(user_ccb))
864 break;
865 TAILQ_REMOVE(abort_queue, user_descr, tqe);
866 user_ccb = user_descr->user_ccb;
867 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
868 ("targread aborted descr %p (%p)\n",
869 user_descr, user_ccb));
870 if (suword(&user_ccb->ccb_h.status, CAM_REQ_ABORTED) != 0) {
871 error = EFAULT;
872 goto read_fail;
873 }
874 cam_periph_unlock(softc->periph);
875 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
876 cam_periph_lock(softc->periph);
877 if (error != 0)
878 goto read_fail;
879 read_len += sizeof(user_ccb);
880
881 user_descr = TAILQ_FIRST(abort_queue);
882 }
883
884 /*
885 * If we've successfully read some amount of data, don't report an
886 * error. If the error is persistent, it will be reported on the
887 * next read().
888 */
889 if (read_len == 0 && uio->uio_resid != 0)
890 error = ENOSPC;
891
892 read_fail:
893 cam_periph_unlock(softc->periph);
894 return (error);
895 }
896
897 /* Copy completed ccb back to the user */
898 static int
targreturnccb(struct targ_softc * softc,union ccb * ccb)899 targreturnccb(struct targ_softc *softc, union ccb *ccb)
900 {
901 struct targ_cmd_descr *descr;
902 struct ccb_hdr *u_ccbh;
903 size_t ccb_len;
904 int error;
905
906 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
907 descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
908 u_ccbh = &descr->user_ccb->ccb_h;
909
910 /* Copy out the central portion of the ccb_hdr */
911 error = copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
912 offsetof(struct ccb_hdr, periph_priv) -
913 offsetof(struct ccb_hdr, retry_count));
914 if (error != 0) {
915 xpt_print(softc->path,
916 "targreturnccb - CCB header copyout failed (%d)\n", error);
917 }
918
919 /* Copy out the rest of the ccb (after the ccb_hdr) */
920 ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
921 if (descr->mapinfo.num_bufs_used != 0) {
922 int error1;
923
924 error1 = cam_periph_unmapmem(ccb, &descr->mapinfo);
925 if (error == 0)
926 error = error1;
927 }
928 if (error == 0) {
929 error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
930 if (error != 0) {
931 xpt_print(softc->path,
932 "targreturnccb - CCB copyout failed (%d)\n", error);
933 }
934 }
935 /* Free CCB or send back to devq. */
936 targfreeccb(softc, ccb);
937
938 return (error);
939 }
940
941 static union ccb *
targgetccb(struct targ_softc * softc,xpt_opcode type,int priority)942 targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
943 {
944 union ccb *ccb;
945 int ccb_len;
946
947 ccb_len = targccblen(type);
948 ccb = malloc(ccb_len, M_TARG, M_NOWAIT | M_ZERO);
949 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
950 if (ccb == NULL) {
951 return (ccb);
952 }
953 xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
954 ccb->ccb_h.func_code = type;
955 ccb->ccb_h.cbfcnp = targdone;
956 ccb->ccb_h.targ_descr = targgetdescr(softc);
957 if (ccb->ccb_h.targ_descr == NULL) {
958 free (ccb, M_TARG);
959 ccb = NULL;
960 }
961 return (ccb);
962 }
963
964 static void
targfreeccb(struct targ_softc * softc,union ccb * ccb)965 targfreeccb(struct targ_softc *softc, union ccb *ccb)
966 {
967 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
968 ccb->ccb_h.targ_descr));
969 free(ccb->ccb_h.targ_descr, M_TARG);
970
971 switch (ccb->ccb_h.func_code) {
972 case XPT_ACCEPT_TARGET_IO:
973 case XPT_IMMED_NOTIFY:
974 case XPT_IMMEDIATE_NOTIFY:
975 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
976 free(ccb, M_TARG);
977 break;
978 default:
979 /* Send back CCB if we got it from the periph */
980 if (XPT_FC_IS_QUEUED(ccb)) {
981 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
982 ("returning queued ccb %p\n", ccb));
983 xpt_release_ccb(ccb);
984 } else {
985 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
986 ("freeing ccb %p\n", ccb));
987 free(ccb, M_TARG);
988 }
989 break;
990 }
991 }
992
993 static struct targ_cmd_descr *
targgetdescr(struct targ_softc * softc)994 targgetdescr(struct targ_softc *softc)
995 {
996 struct targ_cmd_descr *descr;
997
998 descr = malloc(sizeof(*descr), M_TARG,
999 M_NOWAIT);
1000 if (descr) {
1001 descr->mapinfo.num_bufs_used = 0;
1002 }
1003 return (descr);
1004 }
1005
1006 static void
targinit(void)1007 targinit(void)
1008 {
1009 struct cdev *dev;
1010
1011 /* Add symbolic link to targ0 for compatibility. */
1012 dev = make_dev(&targ_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "targ");
1013 make_dev_alias(dev, "targ0");
1014 }
1015
1016 static void
targasync(void * callback_arg,uint32_t code,struct cam_path * path,void * arg)1017 targasync(void *callback_arg, uint32_t code, struct cam_path *path, void *arg)
1018 {
1019 /* All events are handled in usermode by INOTs */
1020 panic("targasync() called, should be an INOT instead");
1021 }
1022
1023 /* Cancel all pending requests and CCBs awaiting work. */
1024 static void
abort_all_pending(struct targ_softc * softc)1025 abort_all_pending(struct targ_softc *softc)
1026 {
1027 struct targ_cmd_descr *descr;
1028 struct ccb_abort cab;
1029 struct ccb_hdr *ccb_h;
1030
1031 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("abort_all_pending\n"));
1032
1033 /* First abort the descriptors awaiting resources */
1034 while ((descr = TAILQ_FIRST(&softc->work_queue)) != NULL) {
1035 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1036 ("Aborting descr from workq %p\n", descr));
1037 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
1038 TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
1039 }
1040
1041 /*
1042 * Then abort all pending CCBs.
1043 * targdone() will return the aborted CCB via user_ccb_queue
1044 */
1045 memset(&cab, 0, sizeof(cab));
1046 xpt_setup_ccb(&cab.ccb_h, softc->path, CAM_PRIORITY_NORMAL);
1047 cab.ccb_h.func_code = XPT_ABORT;
1048 cab.ccb_h.status = CAM_REQ_CMP_ERR;
1049 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue, periph_links.tqe) {
1050 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1051 ("Aborting pending CCB %p\n", ccb_h));
1052 cab.abort_ccb = (union ccb *)ccb_h;
1053 xpt_action((union ccb *)&cab);
1054 if (cab.ccb_h.status != CAM_REQ_CMP) {
1055 xpt_print(cab.ccb_h.path,
1056 "Unable to abort CCB, status %#x\n",
1057 cab.ccb_h.status);
1058 }
1059 }
1060
1061 /* If we aborted at least one pending CCB ok, wait for it. */
1062 if (cab.ccb_h.status == CAM_REQ_CMP) {
1063 cam_periph_sleep(softc->periph, &softc->pending_ccb_queue,
1064 PRIBIO | PCATCH, "tgabrt", 0);
1065 }
1066
1067 /* If we aborted anything from the work queue, wakeup user. */
1068 if (!TAILQ_EMPTY(&softc->user_ccb_queue)
1069 || !TAILQ_EMPTY(&softc->abort_queue)) {
1070 cam_periph_unlock(softc->periph);
1071 notify_user(softc);
1072 cam_periph_lock(softc->periph);
1073 }
1074 }
1075
1076 /* Notify the user that data is ready */
1077 static void
notify_user(struct targ_softc * softc)1078 notify_user(struct targ_softc *softc)
1079 {
1080 /*
1081 * Notify users sleeping via poll(), kqueue(), and
1082 * blocking read().
1083 */
1084 selwakeuppri(&softc->read_select, PRIBIO);
1085 KNOTE_UNLOCKED(&softc->read_select.si_note, 0);
1086 wakeup(&softc->user_ccb_queue);
1087 }
1088
1089 /* Convert CAM status to errno values */
1090 static int
targcamstatus(cam_status status)1091 targcamstatus(cam_status status)
1092 {
1093 switch (status & CAM_STATUS_MASK) {
1094 case CAM_REQ_CMP: /* CCB request completed without error */
1095 return (0);
1096 case CAM_REQ_INPROG: /* CCB request is in progress */
1097 return (EINPROGRESS);
1098 case CAM_REQ_CMP_ERR: /* CCB request completed with an error */
1099 return (EIO);
1100 case CAM_PROVIDE_FAIL: /* Unable to provide requested capability */
1101 return (ENOTTY);
1102 case CAM_FUNC_NOTAVAIL: /* The requested function is not available */
1103 return (ENOTSUP);
1104 case CAM_LUN_ALRDY_ENA: /* LUN is already enabled for target mode */
1105 return (EADDRINUSE);
1106 case CAM_PATH_INVALID: /* Supplied Path ID is invalid */
1107 case CAM_DEV_NOT_THERE: /* SCSI Device Not Installed/there */
1108 return (ENOENT);
1109 case CAM_REQ_ABORTED: /* CCB request aborted by the host */
1110 return (ECANCELED);
1111 case CAM_CMD_TIMEOUT: /* Command timeout */
1112 return (ETIMEDOUT);
1113 case CAM_REQUEUE_REQ: /* Requeue to preserve transaction ordering */
1114 return (EAGAIN);
1115 case CAM_REQ_INVALID: /* CCB request was invalid */
1116 return (EINVAL);
1117 case CAM_RESRC_UNAVAIL: /* Resource Unavailable */
1118 return (ENOMEM);
1119 case CAM_BUSY: /* CAM subsystem is busy */
1120 case CAM_UA_ABORT: /* Unable to abort CCB request */
1121 return (EBUSY);
1122 default:
1123 return (ENXIO);
1124 }
1125 }
1126
1127 static size_t
targccblen(xpt_opcode func_code)1128 targccblen(xpt_opcode func_code)
1129 {
1130 int len;
1131
1132 /* Codes we expect to see as a target */
1133 switch (func_code) {
1134 case XPT_CONT_TARGET_IO:
1135 case XPT_SCSI_IO:
1136 len = sizeof(struct ccb_scsiio);
1137 break;
1138 case XPT_ACCEPT_TARGET_IO:
1139 len = sizeof(struct ccb_accept_tio);
1140 break;
1141 case XPT_IMMED_NOTIFY:
1142 len = sizeof(struct ccb_immed_notify);
1143 break;
1144 case XPT_IMMEDIATE_NOTIFY:
1145 len = sizeof(struct ccb_immediate_notify);
1146 break;
1147 case XPT_REL_SIMQ:
1148 len = sizeof(struct ccb_relsim);
1149 break;
1150 case XPT_PATH_INQ:
1151 len = sizeof(struct ccb_pathinq);
1152 break;
1153 case XPT_DEBUG:
1154 len = sizeof(struct ccb_debug);
1155 break;
1156 case XPT_ABORT:
1157 len = sizeof(struct ccb_abort);
1158 break;
1159 case XPT_EN_LUN:
1160 len = sizeof(struct ccb_en_lun);
1161 break;
1162 default:
1163 len = sizeof(union ccb);
1164 break;
1165 }
1166
1167 return (len);
1168 }
1169