Bring in some CAM bug fixes from FreeBSD.
[dragonfly.git] / sys / bus / cam / scsi / scsi_target.c
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  * $FreeBSD: src/sys/cam/scsi/scsi_target.c,v 1.22.2.7 2003/02/18 22:07:10 njl Exp $
30  * $DragonFly: src/sys/bus/cam/scsi/scsi_target.c,v 1.10 2005/03/15 20:42:14 dillon Exp $
31  */
32
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/conf.h>
37 #include <sys/malloc.h>
38 #include <sys/poll.h>
39 #include <sys/vnode.h>
40 #include <sys/devicestat.h>
41
42 #include "../cam.h"
43 #include "../cam_ccb.h"
44 #include "../cam_periph.h"
45 #include "../cam_xpt_periph.h"
46 #include "scsi_targetio.h"
47
48 /* Transaction information attached to each CCB sent by the user */
49 struct targ_cmd_descr {
50         struct cam_periph_map_info  mapinfo;
51         TAILQ_ENTRY(targ_cmd_descr) tqe;
52         union ccb *user_ccb;
53         int        priority;
54         int        func_code;
55 };
56
57 /* Offset into the private CCB area for storing our descriptor */
58 #define targ_descr      periph_priv.entries[1].ptr
59
60 TAILQ_HEAD(descr_queue, targ_cmd_descr);
61
62 typedef enum {
63         TARG_STATE_RESV         = 0x00, /* Invalid state */
64         TARG_STATE_OPENED       = 0x01, /* Device opened, softc initialized */
65         TARG_STATE_LUN_ENABLED  = 0x02  /* Device enabled for a path */
66 } targ_state;
67
68 /* Per-instance device software context */
69 struct targ_softc {
70         /* CCBs (CTIOs, ATIOs, INOTs) pending on the controller */
71         struct ccb_queue         pending_ccb_queue;
72
73         /* Command descriptors awaiting CTIO resources from the XPT */
74         struct descr_queue       work_queue;
75
76         /* Command descriptors that have been aborted back to the user. */
77         struct descr_queue       abort_queue;
78
79         /*
80          * Queue of CCBs that have been copied out to userland, but our
81          * userland daemon has not yet seen.
82          */
83         struct ccb_queue         user_ccb_queue;
84
85         struct cam_periph       *periph;
86         struct cam_path         *path;
87         targ_state               state;
88         struct selinfo           read_select;
89         struct devstat           device_stats;
90 };
91
92 static d_open_t         targopen;
93 static d_close_t        targclose;
94 static d_read_t         targread;
95 static d_write_t        targwrite;
96 static d_ioctl_t        targioctl;
97 static d_poll_t         targpoll;
98 static d_kqfilter_t     targkqfilter;
99 static void             targreadfiltdetach(struct knote *kn);
100 static int              targreadfilt(struct knote *kn, long hint);
101 static struct filterops targread_filtops =
102         { 1, NULL, targreadfiltdetach, targreadfilt };
103
104 #define TARG_CDEV_MAJOR 65
105 static struct cdevsw targ_cdevsw = {
106         /* name */      "targ",
107         /* maj */       TARG_CDEV_MAJOR,
108         /* flags */     D_KQFILTER,
109         /* port */      NULL,
110         /* clone */     NULL,
111
112         /* open */      targopen,
113         /* close */     targclose,
114         /* read */      targread,
115         /* write */     targwrite,
116         /* ioctl */     targioctl,
117         /* poll */      targpoll,
118         /* mmap */      nommap,
119         /* strategy */  nostrategy,
120         /* dump */      nodump,
121         /* psize */     nopsize,
122         /* 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, u_int32_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 DATA_SET(periphdriver_set, targdriver);
162
163 static MALLOC_DEFINE(M_TARG, "TARG", "TARG data");
164
165 /* Create softc and initialize it. Only one proc can open each targ device. */
166 static int
167 targopen(dev_t dev, int flags, int fmt, struct proc *p)
168 {
169         struct targ_softc *softc;
170
171         if (dev->si_drv1 != 0) {
172                 return (EBUSY);
173         }
174         
175         /* Mark device busy before any potentially blocking operations */
176         dev->si_drv1 = (void *)~0;
177         reference_dev(dev);             /* save ref for later destroy_dev() */
178
179         /* Create the targ device, allocate its softc, initialize it */
180         make_dev(&targ_cdevsw, minor(dev), UID_ROOT, GID_WHEEL, 0600,
181                          "targ%d", lminor(dev));
182         MALLOC(softc, struct targ_softc *, sizeof(*softc), M_TARG,
183                M_INTWAIT | M_ZERO);
184         dev->si_drv1 = softc;
185         softc->state = TARG_STATE_OPENED;
186         softc->periph = NULL;
187         softc->path = NULL;
188
189         TAILQ_INIT(&softc->pending_ccb_queue);
190         TAILQ_INIT(&softc->work_queue);
191         TAILQ_INIT(&softc->abort_queue);
192         TAILQ_INIT(&softc->user_ccb_queue);
193
194         return (0);
195 }
196
197 /* Disable LUN if enabled and teardown softc */
198 static int
199 targclose(dev_t dev, int flag, int fmt, struct proc *p)
200 {
201         struct targ_softc     *softc;
202         int    error;
203
204         softc = (struct targ_softc *)dev->si_drv1;
205         error = targdisable(softc);
206         if (error == CAM_REQ_CMP) {
207                 dev->si_drv1 = 0;
208                 if (softc->periph != NULL) {
209                         cam_periph_invalidate(softc->periph);
210                         softc->periph = NULL;
211                 }
212                 destroy_dev(dev);       /* eats the open ref */
213                 FREE(softc, M_TARG);
214         } else {
215                 release_dev(dev);
216         }
217         return (error);
218 }
219
220 /* Enable/disable LUNs, set debugging level */
221 static int
222 targioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
223 {
224         struct targ_softc *softc;
225         cam_status         status;
226
227         softc = (struct targ_softc *)dev->si_drv1;
228
229         switch (cmd) {
230         case TARGIOCENABLE:
231         {
232                 struct ioc_enable_lun   *new_lun;
233                 struct cam_path         *path;
234
235                 new_lun = (struct ioc_enable_lun *)addr;
236                 status = xpt_create_path(&path, /*periph*/NULL,
237                                          new_lun->path_id,
238                                          new_lun->target_id,
239                                          new_lun->lun_id);
240                 if (status != CAM_REQ_CMP) {
241                         printf("Couldn't create path, status %#x\n", status);
242                         break;
243                 }
244                 status = targenable(softc, path, new_lun->grp6_len,
245                                     new_lun->grp7_len);
246                 xpt_free_path(path);
247                 break;
248         }
249         case TARGIOCDISABLE:
250                 status = targdisable(softc);
251                 break;
252         case TARGIOCDEBUG:
253         {
254 #ifdef  CAMDEBUG
255                 struct ccb_debug cdbg;
256
257                 bzero(&cdbg, sizeof cdbg);
258                 if (*((int *)addr) != 0)
259                         cdbg.flags = CAM_DEBUG_PERIPH;
260                 else
261                         cdbg.flags = CAM_DEBUG_NONE;
262                 xpt_setup_ccb(&cdbg.ccb_h, softc->path, /*priority*/0);
263                 cdbg.ccb_h.func_code = XPT_DEBUG;
264                 cdbg.ccb_h.cbfcnp = targdone;
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                 xpt_action((union ccb *)&cdbg);
272                 status = cdbg.ccb_h.status & CAM_STATUS_MASK;
273 #else
274                 status = CAM_FUNC_NOTAVAIL;
275 #endif
276                 break;
277         }
278         default:
279                 status = CAM_PROVIDE_FAIL;
280                 break;
281         }
282
283         return (targcamstatus(status));
284 }
285
286 /* Writes are always ready, reads wait for user_ccb_queue or abort_queue */
287 static int
288 targpoll(dev_t dev, int poll_events, struct proc *p)
289 {
290         struct targ_softc *softc;
291         int     revents, s;
292
293         softc = (struct targ_softc *)dev->si_drv1;
294
295         /* Poll for write() is always ok. */
296         revents = poll_events & (POLLOUT | POLLWRNORM);
297         if ((poll_events & (POLLIN | POLLRDNORM)) != 0) {
298                 s = splsoftcam();
299                 /* Poll for read() depends on user and abort queues. */
300                 if (!TAILQ_EMPTY(&softc->user_ccb_queue) ||
301                     !TAILQ_EMPTY(&softc->abort_queue)) {
302                         revents |= poll_events & (POLLIN | POLLRDNORM);
303                 }
304                 /* Only sleep if the user didn't poll for write. */
305                 if (revents == 0)
306                         selrecord(p, &softc->read_select);
307                 splx(s);
308         }
309
310         return (revents);
311 }
312
313 static int
314 targkqfilter(dev_t dev, struct knote *kn)
315 {
316         struct  targ_softc *softc;
317         int     s;
318
319         softc = (struct targ_softc *)dev->si_drv1;
320         kn->kn_hook = (caddr_t)softc;
321         kn->kn_fop = &targread_filtops;
322         s = splsoftcam();
323         SLIST_INSERT_HEAD(&softc->read_select.si_note, kn, kn_selnext);
324         splx(s);
325         return (0);
326 }
327
328 static void
329 targreadfiltdetach(struct knote *kn)
330 {
331         struct  targ_softc *softc;
332         int     s;
333
334         softc = (struct targ_softc *)kn->kn_hook;
335         s = splsoftcam();
336         SLIST_REMOVE(&softc->read_select.si_note, kn, knote, kn_selnext);
337         splx(s);
338 }
339
340 /* Notify the user's kqueue when the user queue or abort queue gets a CCB */
341 static int
342 targreadfilt(struct knote *kn, long hint)
343 {
344         struct targ_softc *softc;
345         int     retval, s;
346
347         softc = (struct targ_softc *)kn->kn_hook;
348         s = splsoftcam();
349         retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
350                  !TAILQ_EMPTY(&softc->abort_queue);
351         splx(s);
352         return (retval);
353 }
354
355 /* Send the HBA the enable/disable message */
356 static cam_status
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         xpt_setup_ccb(&en_ccb.ccb_h, path, /*priority*/1);
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(path);
373                 printf("%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
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_setup_ccb(&cpi.ccb_h, path, /*priority*/1);
393         cpi.ccb_h.func_code = XPT_PATH_INQ;
394         xpt_action((union ccb *)&cpi);
395         status = cpi.ccb_h.status & CAM_STATUS_MASK;
396         if (status != CAM_REQ_CMP) {
397                 printf("pathinq failed, status %#x\n", status);
398                 goto enable_fail;
399         }
400         if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
401                 printf("controller does not support target mode\n");
402                 status = CAM_FUNC_NOTAVAIL;
403                 goto enable_fail;
404         }
405
406         /* Destroy any periph on our path if it is disabled */
407         periph = cam_periph_find(path, "targ");
408         if (periph != NULL) {
409                 struct targ_softc *del_softc;
410
411                 del_softc = (struct targ_softc *)periph->softc;
412                 if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
413                         cam_periph_invalidate(del_softc->periph);
414                         del_softc->periph = NULL;
415                 } else {
416                         printf("Requested path still in use by targ%d\n",
417                                periph->unit_number);
418                         status = CAM_LUN_ALRDY_ENA;
419                         goto enable_fail;
420                 }
421         }
422
423         /* Create a periph instance attached to this path */
424         status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
425                         "targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
426         if (status != CAM_REQ_CMP) {
427                 printf("cam_periph_alloc failed, status %#x\n", status);
428                 goto enable_fail;
429         }
430
431         /* Ensure that the periph now exists. */
432         if (cam_periph_find(path, "targ") == NULL) {
433                 panic("targenable: succeeded but no periph?");
434                 /* NOTREACHED */
435         }
436
437         /* Send the enable lun message */
438         status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
439         if (status != CAM_REQ_CMP) {
440                 printf("enable lun failed, status %#x\n", status);
441                 goto enable_fail;
442         }
443         softc->state |= TARG_STATE_LUN_ENABLED;
444
445 enable_fail:
446         return (status);
447 }
448
449 /* Disable this softc's target instance if enabled */
450 static cam_status
451 targdisable(struct targ_softc *softc)
452 {
453         cam_status status;
454         int s;
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         s = splcam();
463         abort_all_pending(softc);
464         splx(s);
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
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
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
521 targwrite(dev_t 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, s;
527         int func_code, priority;
528
529         softc = (struct targ_softc *)dev->si_drv1;
530         write_len = error = 0;
531         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
532                   ("write - uio_resid %d\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 = fuword(&user_ccb->ccb_h.pinfo.priority);
543                 if (priority == -1) {
544                         error = EINVAL;
545                         break;
546                 }
547                 func_code = fuword(&user_ccb->ccb_h.func_code);
548                 switch (func_code) {
549                 case XPT_ACCEPT_TARGET_IO:
550                 case XPT_IMMED_NOTIFY:
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                         s = splsoftcam();
559                         TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
560                                           &ccb->ccb_h,
561                                           periph_links.tqe);
562                         splx(s);
563                         break;
564                 default:
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                                 s = splsoftcam();
574                                 TAILQ_INSERT_TAIL(&softc->work_queue,
575                                                   descr, tqe);
576                                 splx(s);
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                         break;
593                 }
594                 write_len += sizeof(user_ccb);
595         }
596         
597         /*
598          * If we've successfully taken in some amount of
599          * data, return success for that data first.  If
600          * an error is persistent, it will be reported
601          * on the next write.
602          */
603         if (error != 0 && write_len == 0)
604                 return (error);
605         if (write_len == 0 && uio->uio_resid != 0)
606                 return (ENOSPC);
607         return (0);
608 }
609
610 /* Process requests (descrs) via the periph-supplied CCBs */
611 static void
612 targstart(struct cam_periph *periph, union ccb *start_ccb)
613 {
614         struct targ_softc *softc;
615         struct targ_cmd_descr *descr, *next_descr;
616         int s, error;
617
618         softc = (struct targ_softc *)periph->softc;
619         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
620
621         s = splsoftcam();
622         descr = TAILQ_FIRST(&softc->work_queue);
623         if (descr == NULL) {
624                 splx(s);
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                 splx(s);
630
631                 /* Initiate a transaction using the descr and supplied CCB */
632                 error = targusermerge(softc, descr, start_ccb);
633                 if (error == 0)
634                         error = targsendccb(softc, start_ccb, descr);
635                 if (error != 0) {
636                         xpt_print_path(periph->path);
637                         printf("targsendccb failed, err %d\n", error);
638                         xpt_release_ccb(start_ccb);
639                         suword(&descr->user_ccb->ccb_h.status,
640                                CAM_REQ_CMP_ERR);
641                         s = splsoftcam();
642                         TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
643                         splx(s);
644                         notify_user(softc);
645                 }
646
647                 /* If we have more work to do, stay scheduled */
648                 if (next_descr != NULL)
649                         xpt_schedule(periph, next_descr->priority);
650         }
651 }
652
653 static int
654 targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
655               union ccb *ccb)
656 {
657         struct ccb_hdr *u_ccbh, *k_ccbh;
658         size_t ccb_len;
659         int error;
660
661         u_ccbh = &descr->user_ccb->ccb_h;
662         k_ccbh = &ccb->ccb_h;
663
664         /*
665          * There are some fields in the CCB header that need to be
666          * preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
667          */
668         xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
669         k_ccbh->retry_count = fuword(&u_ccbh->retry_count);
670         k_ccbh->func_code = descr->func_code;
671         k_ccbh->flags = fuword(&u_ccbh->flags);
672         k_ccbh->timeout = fuword(&u_ccbh->timeout);
673         ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
674         error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
675         if (error != 0) {
676                 k_ccbh->status = CAM_REQ_CMP_ERR;
677                 return (error);
678         }
679
680         /* Translate usermode abort_ccb pointer to its kernel counterpart */
681         if (k_ccbh->func_code == XPT_ABORT) {
682                 struct ccb_abort *cab;
683                 struct ccb_hdr *ccb_h;
684                 int s;
685
686                 cab = (struct ccb_abort *)ccb;
687                 s = splsoftcam();
688                 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
689                     periph_links.tqe) {
690                         struct targ_cmd_descr *ab_descr;
691
692                         ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
693                         if (ab_descr->user_ccb == cab->abort_ccb) {
694                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
695                                           ("Changing abort for %p to %p\n",
696                                           cab->abort_ccb, ccb_h));
697                                 cab->abort_ccb = (union ccb *)ccb_h;
698                                 break;
699                         }
700                 }
701                 splx(s);
702                 /* CCB not found, set appropriate status */
703                 if (ccb_h == NULL) {
704                         k_ccbh->status = CAM_PATH_INVALID;
705                         error = ESRCH;
706                 }
707         }
708
709         return (error);
710 }
711
712 /* Build and send a kernel CCB formed from descr->user_ccb */
713 static int
714 targsendccb(struct targ_softc *softc, union ccb *ccb,
715             struct targ_cmd_descr *descr)
716 {
717         struct cam_periph_map_info *mapinfo;
718         struct ccb_hdr *ccb_h;
719         int error;
720
721         ccb_h = &ccb->ccb_h;
722         mapinfo = &descr->mapinfo;
723         mapinfo->num_bufs_used = 0;
724
725         /*
726          * There's no way for the user to have a completion
727          * function, so we put our own completion function in here.
728          * We also stash in a reference to our descriptor so targreturnccb()
729          * can find our mapping info.
730          */
731         ccb_h->cbfcnp = targdone;
732         ccb_h->targ_descr = descr;
733
734         /*
735          * We only attempt to map the user memory into kernel space
736          * if they haven't passed in a physical memory pointer,
737          * and if there is actually an I/O operation to perform.
738          * Right now cam_periph_mapmem() only supports SCSI and device
739          * match CCBs.  For the SCSI CCBs, we only pass the CCB in if
740          * there's actually data to map.  cam_periph_mapmem() will do the
741          * right thing, even if there isn't data to map, but since CCBs
742          * without data are a reasonably common occurance (e.g. test unit
743          * ready), it will save a few cycles if we check for it here.
744          */
745         if (((ccb_h->flags & CAM_DATA_PHYS) == 0)
746          && (((ccb_h->func_code == XPT_CONT_TARGET_IO)
747             && ((ccb_h->flags & CAM_DIR_MASK) != CAM_DIR_NONE))
748           || (ccb_h->func_code == XPT_DEV_MATCH))) {
749
750                 error = cam_periph_mapmem(ccb, mapinfo);
751
752                 /*
753                  * cam_periph_mapmem returned an error, we can't continue.
754                  * Return the error to the user.
755                  */
756                 if (error) {
757                         ccb_h->status = CAM_REQ_CMP_ERR;
758                         mapinfo->num_bufs_used = 0;
759                         return (error);
760                 }
761         }
762
763         /*
764          * Once queued on the pending CCB list, this CCB will be protected
765          * by our error recovery handler.
766          */
767         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
768         if (XPT_FC_IS_QUEUED(ccb)) {
769                 int s;
770
771                 s = splsoftcam();
772                 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
773                                   periph_links.tqe);
774                 splx(s);
775         }
776         xpt_action(ccb);
777
778         return (0);
779 }
780
781 /* Completion routine for CCBs (called at splsoftcam) */
782 static void
783 targdone(struct cam_periph *periph, union ccb *done_ccb)
784 {
785         struct targ_softc *softc;
786         cam_status status;
787
788         CAM_DEBUG(periph->path, CAM_DEBUG_PERIPH, ("targdone %p\n", done_ccb));
789         softc = (struct targ_softc *)periph->softc;
790         TAILQ_REMOVE(&softc->pending_ccb_queue, &done_ccb->ccb_h,
791                      periph_links.tqe);
792         status = done_ccb->ccb_h.status & CAM_STATUS_MASK;
793
794         /* If we're no longer enabled, throw away CCB */
795         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
796                 targfreeccb(softc, done_ccb);
797                 return;
798         }
799         /* abort_all_pending() waits for pending queue to be empty */
800         if (TAILQ_EMPTY(&softc->pending_ccb_queue))
801                 wakeup(&softc->pending_ccb_queue);
802
803         switch (done_ccb->ccb_h.func_code) {
804         /* All FC_*_QUEUED CCBs go back to userland */
805         case XPT_IMMED_NOTIFY:
806         case XPT_ACCEPT_TARGET_IO:
807         case XPT_CONT_TARGET_IO:
808                 TAILQ_INSERT_TAIL(&softc->user_ccb_queue, &done_ccb->ccb_h,
809                                   periph_links.tqe);
810                 notify_user(softc);
811                 break;
812         default:
813                 panic("targdone: impossible xpt opcode %#x",
814                       done_ccb->ccb_h.func_code);
815                 /* NOTREACHED */
816         }
817 }
818
819 /* Return CCBs to the user from the user queue and abort queue */
820 static int
821 targread(dev_t dev, struct uio *uio, int ioflag)
822 {
823         struct descr_queue      *abort_queue;
824         struct targ_cmd_descr   *user_descr;
825         struct targ_softc       *softc;
826         struct ccb_queue  *user_queue;
827         struct ccb_hdr    *ccb_h;
828         union  ccb        *user_ccb;
829         int                read_len, error, s;
830
831         error = 0;
832         read_len = 0;
833         softc = (struct targ_softc *)dev->si_drv1;
834         user_queue = &softc->user_ccb_queue;
835         abort_queue = &softc->abort_queue;
836         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targread\n"));
837
838         /* If no data is available, wait or return immediately */
839         s = splsoftcam();
840         ccb_h = TAILQ_FIRST(user_queue);
841         user_descr = TAILQ_FIRST(abort_queue);
842         while (ccb_h == NULL && user_descr == NULL) {
843                 if ((ioflag & IO_NDELAY) == 0) {
844                         error = tsleep(user_queue, PCATCH, "targrd", 0);
845                         ccb_h = TAILQ_FIRST(user_queue);
846                         user_descr = TAILQ_FIRST(abort_queue);
847                         if (error != 0) {
848                                 if (error == ERESTART) {
849                                         continue;
850                                 } else {
851                                         splx(s);
852                                         goto read_fail;
853                                 }
854                         }
855                 } else {
856                         splx(s);
857                         return (EAGAIN);
858                 }
859         }
860
861         /* Data is available so fill the user's buffer */
862         while (ccb_h != NULL) {
863                 struct targ_cmd_descr *descr;
864
865                 if (uio->uio_resid < sizeof(user_ccb))
866                         break;
867                 TAILQ_REMOVE(user_queue, ccb_h, periph_links.tqe);
868                 splx(s);
869                 descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
870                 user_ccb = descr->user_ccb;
871                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
872                           ("targread ccb %p (%p)\n", ccb_h, user_ccb));
873                 error = targreturnccb(softc, (union ccb *)ccb_h);
874                 if (error != 0)
875                         goto read_fail;
876                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
877                 if (error != 0)
878                         goto read_fail;
879                 read_len += sizeof(user_ccb);
880
881                 s = splsoftcam();
882                 ccb_h = TAILQ_FIRST(user_queue);
883         }
884
885         /* Flush out any aborted descriptors */
886         while (user_descr != NULL) {
887                 if (uio->uio_resid < sizeof(user_ccb))
888                         break;
889                 TAILQ_REMOVE(abort_queue, user_descr, tqe);
890                 splx(s);
891                 user_ccb = user_descr->user_ccb;
892                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
893                           ("targread aborted descr %p (%p)\n",
894                           user_descr, user_ccb));
895                 suword(&user_ccb->ccb_h.status, CAM_REQ_ABORTED);
896                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
897                 if (error != 0)
898                         goto read_fail;
899                 read_len += sizeof(user_ccb);
900
901                 s = splsoftcam();
902                 user_descr = TAILQ_FIRST(abort_queue);
903         }
904         splx(s);
905
906         /*
907          * If we've successfully read some amount of data, don't report an
908          * error.  If the error is persistent, it will be reported on the
909          * next read().
910          */
911         if (read_len == 0 && uio->uio_resid != 0)
912                 error = ENOSPC;
913
914 read_fail:
915         return (error);
916 }
917
918 /* Copy completed ccb back to the user */
919 static int
920 targreturnccb(struct targ_softc *softc, union ccb *ccb)
921 {
922         struct targ_cmd_descr *descr;
923         struct ccb_hdr *u_ccbh;
924         size_t ccb_len;
925         int error;
926
927         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
928         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
929         u_ccbh = &descr->user_ccb->ccb_h;
930
931         /* Copy out the central portion of the ccb_hdr */
932         copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
933                 offsetof(struct ccb_hdr, periph_priv) -
934                 offsetof(struct ccb_hdr, retry_count));
935
936         /* Copy out the rest of the ccb (after the ccb_hdr) */
937         ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
938         if (descr->mapinfo.num_bufs_used != 0)
939                 cam_periph_unmapmem(ccb, &descr->mapinfo);
940         error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
941         if (error != 0) {
942                 xpt_print_path(softc->path);
943                 printf("targreturnccb - CCB copyout failed (%d)\n",
944                        error);
945         }
946         /* Free CCB or send back to devq. */
947         targfreeccb(softc, ccb);
948
949         return (error);
950 }
951
952 static union ccb *
953 targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
954 {
955         union ccb *ccb;
956         int ccb_len;
957
958         ccb_len = targccblen(type);
959         MALLOC(ccb, union ccb *, ccb_len, M_TARG, M_INTWAIT);
960         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
961
962         xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
963         ccb->ccb_h.func_code = type;
964         ccb->ccb_h.cbfcnp = targdone;
965         ccb->ccb_h.targ_descr = targgetdescr(softc);
966         return (ccb);
967 }
968
969 static void
970 targfreeccb(struct targ_softc *softc, union ccb *ccb)
971 {
972         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
973                         ccb->ccb_h.targ_descr));
974         FREE(ccb->ccb_h.targ_descr, M_TARG);
975
976         switch (ccb->ccb_h.func_code) {
977         case XPT_ACCEPT_TARGET_IO:
978         case XPT_IMMED_NOTIFY:
979                 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
980                 FREE(ccb, M_TARG);
981                 break;
982         default:
983                 /* Send back CCB if we got it from the periph */
984                 if (XPT_FC_IS_QUEUED(ccb)) {
985                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
986                                         ("returning queued ccb %p\n", ccb));
987                         xpt_release_ccb(ccb);
988                 } else {
989                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
990                                         ("freeing ccb %p\n", ccb));
991                         FREE(ccb, M_TARG);
992                 }
993                 break;
994         }
995 }
996
997 static struct targ_cmd_descr *
998 targgetdescr(struct targ_softc *softc)
999 {
1000         struct targ_cmd_descr *descr;
1001
1002         MALLOC(descr, struct targ_cmd_descr *, sizeof(*descr),
1003                 M_TARG, M_INTWAIT);
1004         descr->mapinfo.num_bufs_used = 0;
1005         return (descr);
1006 }
1007
1008 static void
1009 targinit(void)
1010 {
1011         cdevsw_add(&targ_cdevsw, 0, 0);
1012 }
1013
1014 static void
1015 targasync(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg)
1016 {
1017         /* All events are handled in usermode by INOTs */
1018         panic("targasync() called, should be an INOT instead");
1019 }
1020
1021 /* Cancel all pending requests and CCBs awaiting work. */
1022 static void
1023 abort_all_pending(struct targ_softc *softc)
1024 {
1025         struct targ_cmd_descr   *descr;
1026         struct ccb_abort         cab;
1027         struct ccb_hdr          *ccb_h;
1028
1029         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("abort_all_pending\n"));
1030
1031         /* First abort the descriptors awaiting resources */
1032         while ((descr = TAILQ_FIRST(&softc->work_queue)) != NULL) {
1033                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1034                           ("Aborting descr from workq %p\n", descr));
1035                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
1036                 TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
1037         }
1038
1039         /* 
1040          * Then abort all pending CCBs.
1041          * targdone() will return the aborted CCB via user_ccb_queue
1042          */
1043         xpt_setup_ccb(&cab.ccb_h, softc->path, /*priority*/0);
1044         cab.ccb_h.func_code = XPT_ABORT;
1045         cab.ccb_h.status = CAM_REQ_CMP_ERR;
1046         TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue, periph_links.tqe) {
1047                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1048                           ("Aborting pending CCB %p\n", ccb_h));
1049                 cab.abort_ccb = (union ccb *)ccb_h;
1050                 xpt_action((union ccb *)&cab);
1051                 if (cab.ccb_h.status != CAM_REQ_CMP) {
1052                         xpt_print_path(cab.ccb_h.path);
1053                         printf("Unable to abort CCB, status %#x\n",
1054                                cab.ccb_h.status);
1055                 }
1056         }
1057
1058         /* If we aborted at least one pending CCB ok, wait for it. */
1059         if (cab.ccb_h.status == CAM_REQ_CMP) {
1060                 tsleep(&softc->pending_ccb_queue, PCATCH, "tgabrt", 0);
1061         }
1062
1063         /* If we aborted anything from the work queue, wakeup user. */
1064         if (!TAILQ_EMPTY(&softc->user_ccb_queue)
1065          || !TAILQ_EMPTY(&softc->abort_queue))
1066                 notify_user(softc);
1067 }
1068
1069 /* Notify the user that data is ready */
1070 static void
1071 notify_user(struct targ_softc *softc)
1072 {
1073         /*
1074          * Notify users sleeping via poll(), kqueue(), and
1075          * blocking read().
1076          */
1077         selwakeup(&softc->read_select);
1078         KNOTE(&softc->read_select.si_note, 0);
1079         wakeup(&softc->user_ccb_queue);
1080 }
1081
1082 /* Convert CAM status to errno values */
1083 static int
1084 targcamstatus(cam_status status)
1085 {
1086         switch (status & CAM_STATUS_MASK) {
1087         case CAM_REQ_CMP:       /* CCB request completed without error */
1088                 return (0);
1089         case CAM_REQ_INPROG:    /* CCB request is in progress */
1090                 return (EINPROGRESS);
1091         case CAM_REQ_CMP_ERR:   /* CCB request completed with an error */
1092                 return (EIO);
1093         case CAM_PROVIDE_FAIL:  /* Unable to provide requested capability */
1094                 return (ENOTTY);
1095         case CAM_FUNC_NOTAVAIL: /* The requested function is not available */
1096                 return (ENOTSUP);
1097         case CAM_LUN_ALRDY_ENA: /* LUN is already enabled for target mode */
1098                 return (EADDRINUSE);
1099         case CAM_PATH_INVALID:  /* Supplied Path ID is invalid */
1100         case CAM_DEV_NOT_THERE: /* SCSI Device Not Installed/there */
1101                 return (ENOENT);
1102         case CAM_REQ_ABORTED:   /* CCB request aborted by the host */
1103                 return (ECANCELED);
1104         case CAM_CMD_TIMEOUT:   /* Command timeout */
1105                 return (ETIMEDOUT);
1106         case CAM_REQUEUE_REQ:   /* Requeue to preserve transaction ordering */
1107                 return (EAGAIN);
1108         case CAM_REQ_INVALID:   /* CCB request was invalid */
1109                 return (EINVAL);
1110         case CAM_RESRC_UNAVAIL: /* Resource Unavailable */
1111                 return (ENOMEM);
1112         case CAM_BUSY:          /* CAM subsytem is busy */
1113         case CAM_UA_ABORT:      /* Unable to abort CCB request */
1114                 return (EBUSY);
1115         default:
1116                 return (ENXIO);
1117         }
1118 }
1119
1120 static size_t
1121 targccblen(xpt_opcode func_code)
1122 {
1123         int len;
1124
1125         /* Codes we expect to see as a target */
1126         switch (func_code) {
1127         case XPT_CONT_TARGET_IO:
1128         case XPT_SCSI_IO:
1129                 len = sizeof(struct ccb_scsiio);
1130                 break;
1131         case XPT_ACCEPT_TARGET_IO:
1132                 len = sizeof(struct ccb_accept_tio);
1133                 break;
1134         case XPT_IMMED_NOTIFY:
1135                 len = sizeof(struct ccb_immed_notify);
1136                 break;
1137         case XPT_REL_SIMQ:
1138                 len = sizeof(struct ccb_relsim);
1139                 break;
1140         case XPT_PATH_INQ:
1141                 len = sizeof(struct ccb_pathinq);
1142                 break;
1143         case XPT_DEBUG:
1144                 len = sizeof(struct ccb_debug);
1145                 break;
1146         case XPT_ABORT:
1147                 len = sizeof(struct ccb_abort);
1148                 break;
1149         case XPT_EN_LUN:
1150                 len = sizeof(struct ccb_en_lun);
1151                 break;
1152         default:
1153                 len = sizeof(union ccb);
1154                 break;
1155         }
1156
1157         return (len);
1158 }