f9850b41f54a4f81b2f4c1c50e0864a70dc7208c
[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 1.20 2008/07/18 00:07:23 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/device.h>
38 #include <sys/malloc.h>
39 #include <sys/poll.h>
40 #include <sys/vnode.h>
41 #include <sys/devicestat.h>
42 #include <sys/thread2.h>
43 #include <sys/devfs.h>
44
45 #include "../cam.h"
46 #include "../cam_ccb.h"
47 #include "../cam_periph.h"
48 #include "../cam_xpt_periph.h"
49 #include "../cam_sim.h"
50 #include "scsi_targetio.h"
51
52 /* Transaction information attached to each CCB sent by the user */
53 struct targ_cmd_descr {
54         struct cam_periph_map_info  mapinfo;
55         TAILQ_ENTRY(targ_cmd_descr) tqe;
56         union ccb *user_ccb;
57         int        priority;
58         int        func_code;
59 };
60
61 /* Offset into the private CCB area for storing our descriptor */
62 #define targ_descr      periph_priv.entries[1].ptr
63
64 TAILQ_HEAD(descr_queue, targ_cmd_descr);
65
66 typedef enum {
67         TARG_STATE_RESV         = 0x00, /* Invalid state */
68         TARG_STATE_OPENED       = 0x01, /* Device opened, softc initialized */
69         TARG_STATE_LUN_ENABLED  = 0x02  /* Device enabled for a path */
70 } targ_state;
71
72 /* Per-instance device software context */
73 struct targ_softc {
74         /* CCBs (CTIOs, ATIOs, INOTs) pending on the controller */
75         struct ccb_queue         pending_ccb_queue;
76
77         /* Command descriptors awaiting CTIO resources from the XPT */
78         struct descr_queue       work_queue;
79
80         /* Command descriptors that have been aborted back to the user. */
81         struct descr_queue       abort_queue;
82
83         /*
84          * Queue of CCBs that have been copied out to userland, but our
85          * userland daemon has not yet seen.
86          */
87         struct ccb_queue         user_ccb_queue;
88
89         struct cam_periph       *periph;
90         struct cam_path         *path;
91         targ_state               state;
92         struct selinfo           read_select;
93         struct devstat           device_stats;
94 };
95
96 static d_open_t         targopen;
97 static d_close_t        targclose;
98 static d_read_t         targread;
99 static d_write_t        targwrite;
100 static d_ioctl_t        targioctl;
101 static d_poll_t         targpoll;
102 static d_kqfilter_t     targkqfilter;
103 static d_clone_t        targclone;
104 DEVFS_DECLARE_CLONE_BITMAP(targ);
105
106 static void             targreadfiltdetach(struct knote *kn);
107 static int              targreadfilt(struct knote *kn, long hint);
108 static struct filterops targread_filtops =
109         { 1, NULL, targreadfiltdetach, targreadfilt };
110
111 #define TARG_CDEV_MAJOR 65
112 static struct dev_ops targ_ops = {
113         { "targ", TARG_CDEV_MAJOR, D_KQFILTER },
114         .d_open = targopen,
115         .d_close = targclose,
116         .d_read = targread,
117         .d_write = targwrite,
118         .d_ioctl = targioctl,
119         .d_poll = targpoll,
120         .d_kqfilter = targkqfilter
121 };
122
123 static cam_status       targendislun(struct cam_path *path, int enable,
124                                      int grp6_len, int grp7_len);
125 static cam_status       targenable(struct targ_softc *softc,
126                                    struct cam_path *path,
127                                    int grp6_len, int grp7_len);
128 static cam_status       targdisable(struct targ_softc *softc);
129 static periph_ctor_t    targctor;
130 static periph_dtor_t    targdtor;
131 static periph_start_t   targstart;
132 static int              targusermerge(struct targ_softc *softc,
133                                       struct targ_cmd_descr *descr,
134                                       union ccb *ccb);
135 static int              targsendccb(struct targ_softc *softc, union ccb *ccb,
136                                     struct targ_cmd_descr *descr);
137 static void             targdone(struct cam_periph *periph,
138                                  union  ccb *done_ccb);
139 static int              targreturnccb(struct targ_softc *softc,
140                                       union  ccb *ccb);
141 static union ccb *      targgetccb(struct targ_softc *softc, xpt_opcode type,
142                                    int priority);
143 static void             targfreeccb(struct targ_softc *softc, union ccb *ccb);
144 static struct targ_cmd_descr *
145                         targgetdescr(struct targ_softc *softc);
146 static periph_init_t    targinit;
147 static void             targasync(void *callback_arg, u_int32_t code,
148                                   struct cam_path *path, void *arg);
149 static void             abort_all_pending(struct targ_softc *softc);
150 static void             notify_user(struct targ_softc *softc);
151 static int              targcamstatus(cam_status status);
152 static size_t           targccblen(xpt_opcode func_code);
153
154 static struct periph_driver targdriver =
155 {
156         targinit, "targ",
157         TAILQ_HEAD_INITIALIZER(targdriver.units), /* generation */ 0
158 };
159 PERIPHDRIVER_DECLARE(targ, targdriver);
160
161 static MALLOC_DEFINE(M_TARG, "TARG", "TARG data");
162
163 /*
164  * Create softc and initialize it. Only one proc can open each targ device.
165  * There is no locking here because a periph doesn't get created until an
166  * ioctl is issued to do so, and that can't happen until this method returns.
167  */
168 static int
169 targopen(struct dev_open_args *ap)
170 {
171         cdev_t dev = ap->a_head.a_dev;
172         struct targ_softc *softc;
173
174         if (dev->si_drv1 != 0) {
175                 return (EBUSY);
176         }
177         
178         /* Mark device busy before any potentially blocking operations */
179         dev->si_drv1 = (void *)~0;
180         reference_dev(dev);             /* save ref for later destroy_dev() */
181
182         /* Create the targ device, allocate its softc, initialize it */
183 #if 0
184         make_dev(&targ_ops, minor(dev), UID_ROOT, GID_WHEEL, 0600,
185                          "targ%d", lminor(dev));
186 #endif
187         MALLOC(softc, struct targ_softc *, sizeof(*softc), M_TARG,
188                M_INTWAIT | M_ZERO);
189         dev->si_drv1 = softc;
190         softc->state = TARG_STATE_OPENED;
191         softc->periph = NULL;
192         softc->path = NULL;
193
194         TAILQ_INIT(&softc->pending_ccb_queue);
195         TAILQ_INIT(&softc->work_queue);
196         TAILQ_INIT(&softc->abort_queue);
197         TAILQ_INIT(&softc->user_ccb_queue);
198
199         return (0);
200 }
201
202 /* Disable LUN if enabled and teardown softc */
203 static int
204 targclose(struct dev_close_args *ap)
205 {
206         cdev_t dev = ap->a_head.a_dev;
207         struct targ_softc     *softc;
208         struct cam_periph     *periph;
209         int    error;
210
211         softc = (struct targ_softc *)dev->si_drv1;
212         if ((softc->periph == NULL) ||
213             (softc->state & TARG_STATE_LUN_ENABLED) == 0) {
214                 devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(targ), dev->si_uminor);
215                 destroy_dev(dev);
216                 FREE(softc, M_TARG);
217                 return (0);
218         }
219
220         /*
221          * Acquire a hold on the periph so that it doesn't go away before
222          * we are ready at the end of the function.
223          */
224         periph = softc->periph;
225         cam_periph_acquire(periph);
226         cam_periph_lock(periph);
227         error = targdisable(softc);
228         if (error == CAM_REQ_CMP) {
229                 dev->si_drv1 = 0;
230                 if (softc->periph != NULL) {
231                         cam_periph_invalidate(softc->periph);
232                         softc->periph = NULL;
233                 }
234                 destroy_dev(dev);       /* eats the open ref */
235                 devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(targ), dev->si_uminor);
236                 FREE(softc, M_TARG);
237         } else {
238                 release_dev(dev);
239         }
240         cam_periph_unlock(periph);
241         cam_periph_release(periph);
242
243         return (error);
244 }
245
246 /* Enable/disable LUNs, set debugging level */
247 static int
248 targioctl(struct dev_ioctl_args *ap)
249 {
250         struct targ_softc *softc;
251         cam_status         status;
252
253         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
254
255         switch (ap->a_cmd) {
256         case TARGIOCENABLE:
257         {
258                 struct ioc_enable_lun   *new_lun;
259                 struct cam_path         *path;
260                 struct cam_sim          *sim;
261
262                 new_lun = (struct ioc_enable_lun *)ap->a_data;
263                 status = xpt_create_path_unlocked(&path, /*periph*/NULL,
264                                                   new_lun->path_id,
265                                                   new_lun->target_id,
266                                                   new_lun->lun_id);
267                 if (status != CAM_REQ_CMP) {
268                         kprintf("Couldn't create path, status %#x\n", status);
269                         break;
270                 }
271                 sim = xpt_path_sim(path);
272                 CAM_SIM_LOCK(sim);
273                 status = targenable(softc, path, new_lun->grp6_len,
274                                     new_lun->grp7_len);
275                 xpt_free_path(path);
276                 CAM_SIM_UNLOCK(sim);
277                 break;
278         }
279         case TARGIOCDISABLE:
280                 if (softc->periph == NULL) {
281                         status = CAM_DEV_NOT_THERE;
282                         break;
283                 }
284                 cam_periph_lock(softc->periph);
285                 status = targdisable(softc);
286                 cam_periph_unlock(softc->periph);
287                 break;
288         case TARGIOCDEBUG:
289         {
290 #ifdef  CAMDEBUG
291                 struct ccb_debug cdbg;
292
293                 /* If no periph available, disallow debugging changes */
294                 if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
295                         status = CAM_DEV_NOT_THERE;
296                         break;
297                 }
298                 bzero(&cdbg, sizeof cdbg);
299                 if (*((int *)ap->a_data) != 0)
300                         cdbg.flags = CAM_DEBUG_PERIPH;
301                 else
302                         cdbg.flags = CAM_DEBUG_NONE;
303                 cam_periph_lock(softc->periph);
304                 xpt_setup_ccb(&cdbg.ccb_h, softc->path, /*priority*/0);
305                 cdbg.ccb_h.func_code = XPT_DEBUG;
306                 cdbg.ccb_h.cbfcnp = targdone;
307
308                 xpt_action((union ccb *)&cdbg);
309                 cam_periph_unlock(softc->periph);
310                 status = cdbg.ccb_h.status & CAM_STATUS_MASK;
311 #else
312                 status = CAM_FUNC_NOTAVAIL;
313 #endif
314                 break;
315         }
316         default:
317                 status = CAM_PROVIDE_FAIL;
318                 break;
319         }
320
321         return (targcamstatus(status));
322 }
323
324 /* Writes are always ready, reads wait for user_ccb_queue or abort_queue */
325 static int
326 targpoll(struct dev_poll_args *ap)
327 {
328         struct targ_softc *softc;
329         int     revents;
330
331         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
332
333         /* Poll for write() is always ok. */
334         revents = ap->a_events & (POLLOUT | POLLWRNORM);
335         if ((ap->a_events & (POLLIN | POLLRDNORM)) != 0) {
336                 /* Poll for read() depends on user and abort queues. */
337                 cam_periph_lock(softc->periph);
338                 if (!TAILQ_EMPTY(&softc->user_ccb_queue) ||
339                     !TAILQ_EMPTY(&softc->abort_queue)) {
340                         revents |= ap->a_events & (POLLIN | POLLRDNORM);
341                 }
342                 cam_periph_unlock(softc->periph);
343                 /* Only sleep if the user didn't poll for write. */
344                 if (revents == 0)
345                         selrecord(curthread, &softc->read_select);
346         }
347         ap->a_events = revents;
348         return (0);
349 }
350
351 static int
352 targkqfilter(struct dev_kqfilter_args *ap)
353 {
354         struct  knote *kn = ap->a_kn;
355         struct  targ_softc *softc;
356
357         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
358         kn->kn_hook = (caddr_t)softc;
359         kn->kn_fop = &targread_filtops;
360         crit_enter();
361         SLIST_INSERT_HEAD(&softc->read_select.si_note, kn, kn_selnext);
362         crit_exit();
363         return (0);
364 }
365
366 static void
367 targreadfiltdetach(struct knote *kn)
368 {
369         struct  targ_softc *softc;
370
371         softc = (struct targ_softc *)kn->kn_hook;
372         crit_enter();
373         SLIST_REMOVE(&softc->read_select.si_note, kn, knote, kn_selnext);
374         crit_exit();
375 }
376
377 /* Notify the user's kqueue when the user queue or abort queue gets a CCB */
378 static int
379 targreadfilt(struct knote *kn, long hint)
380 {
381         struct targ_softc *softc;
382         int     retval;
383
384         softc = (struct targ_softc *)kn->kn_hook;
385         cam_periph_lock(softc->periph);
386         retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
387                  !TAILQ_EMPTY(&softc->abort_queue);
388         cam_periph_unlock(softc->periph);
389         return (retval);
390 }
391
392 /* Send the HBA the enable/disable message */
393 static cam_status
394 targendislun(struct cam_path *path, int enable, int grp6_len, int grp7_len)
395 {
396         struct ccb_en_lun en_ccb;
397         cam_status        status;
398
399         /* Tell the lun to begin answering selects */
400         xpt_setup_ccb(&en_ccb.ccb_h, path, /*priority*/1);
401         en_ccb.ccb_h.func_code = XPT_EN_LUN;
402         /* Don't need support for any vendor specific commands */
403         en_ccb.grp6_len = grp6_len;
404         en_ccb.grp7_len = grp7_len;
405         en_ccb.enable = enable ? 1 : 0;
406         xpt_action((union ccb *)&en_ccb);
407         status = en_ccb.ccb_h.status & CAM_STATUS_MASK;
408         if (status != CAM_REQ_CMP) {
409                 xpt_print(path, "%sable lun CCB rejected, status %#x\n",
410                     enable ? "en" : "dis", status);
411         }
412         return (status);
413 }
414
415 /* Enable target mode on a LUN, given its path */
416 static cam_status
417 targenable(struct targ_softc *softc, struct cam_path *path, int grp6_len,
418            int grp7_len)
419 {
420         struct cam_periph *periph;
421         struct ccb_pathinq cpi;
422         cam_status         status;
423
424         if ((softc->state & TARG_STATE_LUN_ENABLED) != 0)
425                 return (CAM_LUN_ALRDY_ENA);
426
427         /* Make sure SIM supports target mode */
428         xpt_setup_ccb(&cpi.ccb_h, path, /*priority*/1);
429         cpi.ccb_h.func_code = XPT_PATH_INQ;
430         xpt_action((union ccb *)&cpi);
431         status = cpi.ccb_h.status & CAM_STATUS_MASK;
432         if (status != CAM_REQ_CMP) {
433                 kprintf("pathinq failed, status %#x\n", status);
434                 goto enable_fail;
435         }
436         if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
437                 kprintf("controller does not support target mode\n");
438                 status = CAM_FUNC_NOTAVAIL;
439                 goto enable_fail;
440         }
441
442         /* Destroy any periph on our path if it is disabled */
443         periph = cam_periph_find(path, "targ");
444         if (periph != NULL) {
445                 struct targ_softc *del_softc;
446
447                 del_softc = (struct targ_softc *)periph->softc;
448                 if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
449                         cam_periph_invalidate(del_softc->periph);
450                         del_softc->periph = NULL;
451                 } else {
452                         kprintf("Requested path still in use by targ%d\n",
453                                periph->unit_number);
454                         status = CAM_LUN_ALRDY_ENA;
455                         goto enable_fail;
456                 }
457         }
458
459         /* Create a periph instance attached to this path */
460         status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
461                         "targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
462         if (status != CAM_REQ_CMP) {
463                 kprintf("cam_periph_alloc failed, status %#x\n", status);
464                 goto enable_fail;
465         }
466
467         /* Ensure that the periph now exists. */
468         if (cam_periph_find(path, "targ") == NULL) {
469                 panic("targenable: succeeded but no periph?");
470                 /* NOTREACHED */
471         }
472
473         /* Send the enable lun message */
474         status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
475         if (status != CAM_REQ_CMP) {
476                 kprintf("enable lun failed, status %#x\n", status);
477                 goto enable_fail;
478         }
479         softc->state |= TARG_STATE_LUN_ENABLED;
480
481 enable_fail:
482         return (status);
483 }
484
485 /* Disable this softc's target instance if enabled */
486 static cam_status
487 targdisable(struct targ_softc *softc)
488 {
489         cam_status status;
490
491         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0)
492                 return (CAM_REQ_CMP);
493
494         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targdisable\n"));
495
496         /* Abort any ccbs pending on the controller */
497         crit_enter();
498         abort_all_pending(softc);
499         crit_exit();
500
501         /* Disable this lun */
502         status = targendislun(softc->path, /*enable*/0,
503                               /*grp6_len*/0, /*grp7_len*/0);
504         if (status == CAM_REQ_CMP)
505                 softc->state &= ~TARG_STATE_LUN_ENABLED;
506         else
507                 kprintf("Disable lun failed, status %#x\n", status);
508
509         return (status);
510 }
511
512 /* Initialize a periph (called from cam_periph_alloc) */
513 static cam_status
514 targctor(struct cam_periph *periph, void *arg)
515 {
516         struct targ_softc *softc;
517
518         /* Store pointer to softc for periph-driven routines */
519         softc = (struct targ_softc *)arg;
520         periph->softc = softc;
521         softc->periph = periph;
522         softc->path = periph->path;
523         return (CAM_REQ_CMP);
524 }
525
526 static void
527 targdtor(struct cam_periph *periph)
528 {
529         struct targ_softc     *softc;
530         struct ccb_hdr        *ccb_h;
531         struct targ_cmd_descr *descr;
532
533         softc = (struct targ_softc *)periph->softc;
534
535         /* 
536          * targdisable() aborts CCBs back to the user and leaves them
537          * on user_ccb_queue and abort_queue in case the user is still
538          * interested in them.  We free them now.
539          */
540         while ((ccb_h = TAILQ_FIRST(&softc->user_ccb_queue)) != NULL) {
541                 TAILQ_REMOVE(&softc->user_ccb_queue, ccb_h, periph_links.tqe);
542                 targfreeccb(softc, (union ccb *)ccb_h);
543         }
544         while ((descr = TAILQ_FIRST(&softc->abort_queue)) != NULL) {
545                 TAILQ_REMOVE(&softc->abort_queue, descr, tqe);
546                 FREE(descr, M_TARG);
547         }
548
549         softc->periph = NULL;
550         softc->path = NULL;
551         periph->softc = NULL;
552 }
553
554 /* Receive CCBs from user mode proc and send them to the HBA */
555 static int
556 targwrite(struct dev_write_args *ap)
557 {
558         struct uio *uio = ap->a_uio;
559         union ccb *user_ccb;
560         struct targ_softc *softc;
561         struct targ_cmd_descr *descr;
562         int write_len, error;
563         int func_code, priority;
564
565         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
566         write_len = error = 0;
567         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
568                   ("write - uio_resid %d\n", uio->uio_resid));
569         while (uio->uio_resid >= sizeof(user_ccb) && error == 0) {
570                 union ccb *ccb;
571
572                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
573                 if (error != 0) {
574                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
575                                   ("write - uiomove failed (%d)\n", error));
576                         break;
577                 }
578                 priority = fuword(&user_ccb->ccb_h.pinfo.priority);
579                 if (priority == -1) {
580                         error = EINVAL;
581                         break;
582                 }
583                 func_code = fuword(&user_ccb->ccb_h.func_code);
584                 switch (func_code) {
585                 case XPT_ACCEPT_TARGET_IO:
586                 case XPT_IMMED_NOTIFY:
587                         cam_periph_lock(softc->periph);
588                         ccb = targgetccb(softc, func_code, priority);
589                         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
590                         descr->user_ccb = user_ccb;
591                         descr->func_code = func_code;
592                         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
593                                   ("Sent ATIO/INOT (%p)\n", user_ccb));
594                         xpt_action(ccb);
595                         TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
596                                           &ccb->ccb_h,
597                                           periph_links.tqe);
598                         cam_periph_unlock(softc->periph);
599                         break;
600                 default:
601                         cam_periph_lock(softc->periph);
602                         if ((func_code & XPT_FC_QUEUED) != 0) {
603                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
604                                           ("Sending queued ccb %#x (%p)\n",
605                                           func_code, user_ccb));
606                                 descr = targgetdescr(softc);
607                                 descr->user_ccb = user_ccb;
608                                 descr->priority = priority;
609                                 descr->func_code = func_code;
610                                 crit_enter();
611                                 TAILQ_INSERT_TAIL(&softc->work_queue,
612                                                   descr, tqe);
613                                 crit_exit();
614                                 xpt_schedule(softc->periph, priority);
615                         } else {
616                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
617                                           ("Sending inline ccb %#x (%p)\n",
618                                           func_code, user_ccb));
619                                 ccb = targgetccb(softc, func_code, priority);
620                                 descr = (struct targ_cmd_descr *)
621                                          ccb->ccb_h.targ_descr;
622                                 descr->user_ccb = user_ccb;
623                                 descr->priority = priority;
624                                 descr->func_code = func_code;
625                                 if (targusermerge(softc, descr, ccb) != EFAULT)
626                                         targsendccb(softc, ccb, descr);
627                                 targreturnccb(softc, ccb);
628                         }
629                         cam_periph_unlock(softc->periph);
630                         break;
631                 }
632                 write_len += sizeof(user_ccb);
633         }
634         
635         /*
636          * If we've successfully taken in some amount of
637          * data, return success for that data first.  If
638          * an error is persistent, it will be reported
639          * on the next write.
640          */
641         if (error != 0 && write_len == 0)
642                 return (error);
643         if (write_len == 0 && uio->uio_resid != 0)
644                 return (ENOSPC);
645         return (0);
646 }
647
648 /* Process requests (descrs) via the periph-supplied CCBs */
649 static void
650 targstart(struct cam_periph *periph, union ccb *start_ccb)
651 {
652         struct targ_softc *softc;
653         struct targ_cmd_descr *descr, *next_descr;
654         int error;
655
656         softc = (struct targ_softc *)periph->softc;
657         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
658
659         crit_enter();
660         descr = TAILQ_FIRST(&softc->work_queue);
661         if (descr == NULL) {
662                 crit_exit();
663                 xpt_release_ccb(start_ccb);
664         } else {
665                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
666                 next_descr = TAILQ_FIRST(&softc->work_queue);
667                 crit_exit();
668
669                 /* Initiate a transaction using the descr and supplied CCB */
670                 error = targusermerge(softc, descr, start_ccb);
671                 if (error == 0)
672                         error = targsendccb(softc, start_ccb, descr);
673                 if (error != 0) {
674                         xpt_print(periph->path,
675                             "targsendccb failed, err %d\n", error);
676                         xpt_release_ccb(start_ccb);
677                         suword(&descr->user_ccb->ccb_h.status,
678                                CAM_REQ_CMP_ERR);
679                         crit_enter();
680                         TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
681                         crit_exit();
682                         notify_user(softc);
683                 }
684
685                 /* If we have more work to do, stay scheduled */
686                 if (next_descr != NULL)
687                         xpt_schedule(periph, next_descr->priority);
688         }
689 }
690
691 static int
692 targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
693               union ccb *ccb)
694 {
695         struct ccb_hdr *u_ccbh, *k_ccbh;
696         size_t ccb_len;
697         int error;
698
699         u_ccbh = &descr->user_ccb->ccb_h;
700         k_ccbh = &ccb->ccb_h;
701
702         /*
703          * There are some fields in the CCB header that need to be
704          * preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
705          */
706         xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
707         k_ccbh->retry_count = fuword(&u_ccbh->retry_count);
708         k_ccbh->func_code = descr->func_code;
709         k_ccbh->flags = fuword(&u_ccbh->flags);
710         k_ccbh->timeout = fuword(&u_ccbh->timeout);
711         ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
712         error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
713         if (error != 0) {
714                 k_ccbh->status = CAM_REQ_CMP_ERR;
715                 return (error);
716         }
717
718         /* Translate usermode abort_ccb pointer to its kernel counterpart */
719         if (k_ccbh->func_code == XPT_ABORT) {
720                 struct ccb_abort *cab;
721                 struct ccb_hdr *ccb_h;
722
723                 cab = (struct ccb_abort *)ccb;
724                 crit_enter();
725                 TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
726                     periph_links.tqe) {
727                         struct targ_cmd_descr *ab_descr;
728
729                         ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
730                         if (ab_descr->user_ccb == cab->abort_ccb) {
731                                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
732                                           ("Changing abort for %p to %p\n",
733                                           cab->abort_ccb, ccb_h));
734                                 cab->abort_ccb = (union ccb *)ccb_h;
735                                 break;
736                         }
737                 }
738                 crit_exit();
739                 /* CCB not found, set appropriate status */
740                 if (ccb_h == NULL) {
741                         k_ccbh->status = CAM_PATH_INVALID;
742                         error = ESRCH;
743                 }
744         }
745
746         return (error);
747 }
748
749 /* Build and send a kernel CCB formed from descr->user_ccb */
750 static int
751 targsendccb(struct targ_softc *softc, union ccb *ccb,
752             struct targ_cmd_descr *descr)
753 {
754         struct cam_periph_map_info *mapinfo;
755         struct ccb_hdr *ccb_h;
756         int error;
757
758         ccb_h = &ccb->ccb_h;
759         mapinfo = &descr->mapinfo;
760         mapinfo->num_bufs_used = 0;
761
762         /*
763          * There's no way for the user to have a completion
764          * function, so we put our own completion function in here.
765          * We also stash in a reference to our descriptor so targreturnccb()
766          * can find our mapping info.
767          */
768         ccb_h->cbfcnp = targdone;
769         ccb_h->targ_descr = descr;
770
771         /*
772          * We only attempt to map the user memory into kernel space
773          * if they haven't passed in a physical memory pointer,
774          * and if there is actually an I/O operation to perform.
775          * Right now cam_periph_mapmem() only supports SCSI and device
776          * match CCBs.  For the SCSI CCBs, we only pass the CCB in if
777          * there's actually data to map.  cam_periph_mapmem() will do the
778          * right thing, even if there isn't data to map, but since CCBs
779          * without data are a reasonably common occurance (e.g. test unit
780          * ready), it will save a few cycles if we check for it here.
781          */
782         if (((ccb_h->flags & CAM_DATA_PHYS) == 0)
783          && (((ccb_h->func_code == XPT_CONT_TARGET_IO)
784             && ((ccb_h->flags & CAM_DIR_MASK) != CAM_DIR_NONE))
785           || (ccb_h->func_code == XPT_DEV_MATCH))) {
786
787                 error = cam_periph_mapmem(ccb, mapinfo);
788
789                 /*
790                  * cam_periph_mapmem returned an error, we can't continue.
791                  * Return the error to the user.
792                  */
793                 if (error) {
794                         ccb_h->status = CAM_REQ_CMP_ERR;
795                         mapinfo->num_bufs_used = 0;
796                         return (error);
797                 }
798         }
799
800         /*
801          * Once queued on the pending CCB list, this CCB will be protected
802          * by our error recovery handler.
803          */
804         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
805         if (XPT_FC_IS_QUEUED(ccb)) {
806                 crit_enter();
807                 TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
808                                   periph_links.tqe);
809                 crit_exit();
810         }
811         xpt_action(ccb);
812
813         return (0);
814 }
815
816 /* Completion routine for CCBs (called in a critical section) */
817 static void
818 targdone(struct cam_periph *periph, union ccb *done_ccb)
819 {
820         struct targ_softc *softc;
821         cam_status status;
822
823         CAM_DEBUG(periph->path, CAM_DEBUG_PERIPH, ("targdone %p\n", done_ccb));
824         softc = (struct targ_softc *)periph->softc;
825         TAILQ_REMOVE(&softc->pending_ccb_queue, &done_ccb->ccb_h,
826                      periph_links.tqe);
827         status = done_ccb->ccb_h.status & CAM_STATUS_MASK;
828
829         /* If we're no longer enabled, throw away CCB */
830         if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
831                 targfreeccb(softc, done_ccb);
832                 return;
833         }
834         /* abort_all_pending() waits for pending queue to be empty */
835         if (TAILQ_EMPTY(&softc->pending_ccb_queue))
836                 wakeup(&softc->pending_ccb_queue);
837
838         switch (done_ccb->ccb_h.func_code) {
839         /* All FC_*_QUEUED CCBs go back to userland */
840         case XPT_IMMED_NOTIFY:
841         case XPT_ACCEPT_TARGET_IO:
842         case XPT_CONT_TARGET_IO:
843                 TAILQ_INSERT_TAIL(&softc->user_ccb_queue, &done_ccb->ccb_h,
844                                   periph_links.tqe);
845                 notify_user(softc);
846                 break;
847         default:
848                 panic("targdone: impossible xpt opcode %#x",
849                       done_ccb->ccb_h.func_code);
850                 /* NOTREACHED */
851         }
852 }
853
854 /* Return CCBs to the user from the user queue and abort queue */
855 static int
856 targread(struct dev_read_args *ap)
857 {
858         struct uio *uio = ap->a_uio;
859         struct descr_queue      *abort_queue;
860         struct targ_cmd_descr   *user_descr;
861         struct targ_softc       *softc;
862         struct ccb_queue  *user_queue;
863         struct ccb_hdr    *ccb_h;
864         union  ccb        *user_ccb;
865         int                read_len, error;
866
867         error = 0;
868         read_len = 0;
869         softc = (struct targ_softc *)ap->a_head.a_dev->si_drv1;
870         user_queue = &softc->user_ccb_queue;
871         abort_queue = &softc->abort_queue;
872         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targread\n"));
873
874         /* If no data is available, wait or return immediately */
875         cam_periph_lock(softc->periph);
876         ccb_h = TAILQ_FIRST(user_queue);
877         user_descr = TAILQ_FIRST(abort_queue);
878         while (ccb_h == NULL && user_descr == NULL) {
879                 if ((ap->a_ioflag & IO_NDELAY) == 0) {
880                         error = sim_lock_sleep(user_queue, PCATCH, "targrd", 0,
881                                                softc->periph->sim->lock);
882                         ccb_h = TAILQ_FIRST(user_queue);
883                         user_descr = TAILQ_FIRST(abort_queue);
884                         if (error != 0) {
885                                 if (error == ERESTART) {
886                                         continue;
887                                 } else {
888                                         goto read_fail;
889                                 }
890                         }
891                 } else {
892                         cam_periph_unlock(softc->periph);
893                         return (EAGAIN);
894                 }
895         }
896
897         /* Data is available so fill the user's buffer */
898         while (ccb_h != NULL) {
899                 struct targ_cmd_descr *descr;
900
901                 if (uio->uio_resid < sizeof(user_ccb))
902                         break;
903                 TAILQ_REMOVE(user_queue, ccb_h, periph_links.tqe);
904                 descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
905                 user_ccb = descr->user_ccb;
906                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
907                           ("targread ccb %p (%p)\n", ccb_h, user_ccb));
908                 error = targreturnccb(softc, (union ccb *)ccb_h);
909                 if (error != 0)
910                         goto read_fail;
911                 cam_periph_unlock(softc->periph);
912                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
913                 cam_periph_lock(softc->periph);
914                 if (error != 0)
915                         goto read_fail;
916                 read_len += sizeof(user_ccb);
917
918                 ccb_h = TAILQ_FIRST(user_queue);
919         }
920
921         /* Flush out any aborted descriptors */
922         while (user_descr != NULL) {
923                 if (uio->uio_resid < sizeof(user_ccb))
924                         break;
925                 TAILQ_REMOVE(abort_queue, user_descr, tqe);
926                 user_ccb = user_descr->user_ccb;
927                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
928                           ("targread aborted descr %p (%p)\n",
929                           user_descr, user_ccb));
930                 suword(&user_ccb->ccb_h.status, CAM_REQ_ABORTED);
931                 cam_periph_unlock(softc->periph);
932                 error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
933                 cam_periph_lock(softc->periph);
934                 if (error != 0)
935                         goto read_fail;
936                 read_len += sizeof(user_ccb);
937
938                 user_descr = TAILQ_FIRST(abort_queue);
939         }
940
941         /*
942          * If we've successfully read some amount of data, don't report an
943          * error.  If the error is persistent, it will be reported on the
944          * next read().
945          */
946         if (read_len == 0 && uio->uio_resid != 0)
947                 error = ENOSPC;
948
949 read_fail:
950         cam_periph_unlock(softc->periph);
951         return (error);
952 }
953
954 /* Copy completed ccb back to the user */
955 static int
956 targreturnccb(struct targ_softc *softc, union ccb *ccb)
957 {
958         struct targ_cmd_descr *descr;
959         struct ccb_hdr *u_ccbh;
960         size_t ccb_len;
961         int error;
962
963         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
964         descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
965         u_ccbh = &descr->user_ccb->ccb_h;
966
967         /* Copy out the central portion of the ccb_hdr */
968         copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
969                 offsetof(struct ccb_hdr, periph_priv) -
970                 offsetof(struct ccb_hdr, retry_count));
971
972         /* Copy out the rest of the ccb (after the ccb_hdr) */
973         ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
974         if (descr->mapinfo.num_bufs_used != 0)
975                 cam_periph_unmapmem(ccb, &descr->mapinfo);
976         error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
977         if (error != 0) {
978                 xpt_print(softc->path,
979                     "targreturnccb - CCB copyout failed (%d)\n", error);
980         }
981         /* Free CCB or send back to devq. */
982         targfreeccb(softc, ccb);
983
984         return (error);
985 }
986
987 static union ccb *
988 targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
989 {
990         union ccb *ccb;
991         int ccb_len;
992
993         ccb_len = targccblen(type);
994         MALLOC(ccb, union ccb *, ccb_len, M_TARG, M_INTWAIT);
995         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
996
997         xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
998         ccb->ccb_h.func_code = type;
999         ccb->ccb_h.cbfcnp = targdone;
1000         ccb->ccb_h.targ_descr = targgetdescr(softc);
1001         return (ccb);
1002 }
1003
1004 static void
1005 targfreeccb(struct targ_softc *softc, union ccb *ccb)
1006 {
1007         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
1008                         ccb->ccb_h.targ_descr));
1009         FREE(ccb->ccb_h.targ_descr, M_TARG);
1010
1011         switch (ccb->ccb_h.func_code) {
1012         case XPT_ACCEPT_TARGET_IO:
1013         case XPT_IMMED_NOTIFY:
1014                 CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
1015                 FREE(ccb, M_TARG);
1016                 break;
1017         default:
1018                 /* Send back CCB if we got it from the periph */
1019                 if (XPT_FC_IS_QUEUED(ccb)) {
1020                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
1021                                         ("returning queued ccb %p\n", ccb));
1022                         xpt_release_ccb(ccb);
1023                 } else {
1024                         CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
1025                                         ("freeing ccb %p\n", ccb));
1026                         FREE(ccb, M_TARG);
1027                 }
1028                 break;
1029         }
1030 }
1031
1032 static struct targ_cmd_descr *
1033 targgetdescr(struct targ_softc *softc)
1034 {
1035         struct targ_cmd_descr *descr;
1036
1037         MALLOC(descr, struct targ_cmd_descr *, sizeof(*descr),
1038                 M_TARG, M_INTWAIT);
1039         descr->mapinfo.num_bufs_used = 0;
1040         return (descr);
1041 }
1042
1043 static int
1044 targclone(struct dev_clone_args *ap)
1045 {
1046         int unit;
1047
1048         unit = devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(targ), 0);
1049         ap->a_dev = make_only_dev(&targ_ops, unit, UID_ROOT, GID_WHEEL,
1050                                   0600, "targ%d", unit);
1051         return 0;
1052 }
1053
1054 static void
1055 targinit(void)
1056 {
1057         make_autoclone_dev(&targ_ops, &DEVFS_CLONE_BITMAP(targ),
1058                 targclone, UID_ROOT, GID_WHEEL, 0600, "targ");
1059         /* XXX: need uninit or so? */
1060 }
1061
1062 static void
1063 targasync(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg)
1064 {
1065         /* All events are handled in usermode by INOTs */
1066         panic("targasync() called, should be an INOT instead");
1067 }
1068
1069 /* Cancel all pending requests and CCBs awaiting work. */
1070 static void
1071 abort_all_pending(struct targ_softc *softc)
1072 {
1073         struct targ_cmd_descr   *descr;
1074         struct ccb_abort         cab;
1075         struct ccb_hdr          *ccb_h;
1076         struct cam_sim          *sim;
1077
1078         CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("abort_all_pending\n"));
1079
1080         /* First abort the descriptors awaiting resources */
1081         while ((descr = TAILQ_FIRST(&softc->work_queue)) != NULL) {
1082                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1083                           ("Aborting descr from workq %p\n", descr));
1084                 TAILQ_REMOVE(&softc->work_queue, descr, tqe);
1085                 TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
1086         }
1087
1088         /* 
1089          * Then abort all pending CCBs.
1090          * targdone() will return the aborted CCB via user_ccb_queue
1091          */
1092         xpt_setup_ccb(&cab.ccb_h, softc->path, /*priority*/0);
1093         cab.ccb_h.func_code = XPT_ABORT;
1094         cab.ccb_h.status = CAM_REQ_CMP_ERR;
1095         TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue, periph_links.tqe) {
1096                 CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
1097                           ("Aborting pending CCB %p\n", ccb_h));
1098                 cab.abort_ccb = (union ccb *)ccb_h;
1099                 xpt_action((union ccb *)&cab);
1100                 if (cab.ccb_h.status != CAM_REQ_CMP) {
1101                         xpt_print(cab.ccb_h.path,
1102                             "Unable to abort CCB, status %#x\n",
1103                             cab.ccb_h.status);
1104                 }
1105         }
1106
1107         /* If we aborted at least one pending CCB ok, wait for it. */
1108         if (cab.ccb_h.status == CAM_REQ_CMP) {
1109                 sim = xpt_path_sim(softc->path);
1110                 sim_lock_sleep(&softc->pending_ccb_queue, PCATCH, "tgabrt", 0,
1111                                sim->lock);
1112         }
1113
1114         /* If we aborted anything from the work queue, wakeup user. */
1115         if (!TAILQ_EMPTY(&softc->user_ccb_queue)
1116          || !TAILQ_EMPTY(&softc->abort_queue))
1117                 notify_user(softc);
1118 }
1119
1120 /* Notify the user that data is ready */
1121 static void
1122 notify_user(struct targ_softc *softc)
1123 {
1124         /*
1125          * Notify users sleeping via poll(), kqueue(), and
1126          * blocking read().
1127          */
1128         selwakeup(&softc->read_select);
1129         KNOTE(&softc->read_select.si_note, 0);
1130         wakeup(&softc->user_ccb_queue);
1131 }
1132
1133 /* Convert CAM status to errno values */
1134 static int
1135 targcamstatus(cam_status status)
1136 {
1137         switch (status & CAM_STATUS_MASK) {
1138         case CAM_REQ_CMP:       /* CCB request completed without error */
1139                 return (0);
1140         case CAM_REQ_INPROG:    /* CCB request is in progress */
1141                 return (EINPROGRESS);
1142         case CAM_REQ_CMP_ERR:   /* CCB request completed with an error */
1143                 return (EIO);
1144         case CAM_PROVIDE_FAIL:  /* Unable to provide requested capability */
1145                 return (ENOTTY);
1146         case CAM_FUNC_NOTAVAIL: /* The requested function is not available */
1147                 return (ENOTSUP);
1148         case CAM_LUN_ALRDY_ENA: /* LUN is already enabled for target mode */
1149                 return (EADDRINUSE);
1150         case CAM_PATH_INVALID:  /* Supplied Path ID is invalid */
1151         case CAM_DEV_NOT_THERE: /* SCSI Device Not Installed/there */
1152                 return (ENOENT);
1153         case CAM_REQ_ABORTED:   /* CCB request aborted by the host */
1154                 return (ECANCELED);
1155         case CAM_CMD_TIMEOUT:   /* Command timeout */
1156                 return (ETIMEDOUT);
1157         case CAM_REQUEUE_REQ:   /* Requeue to preserve transaction ordering */
1158                 return (EAGAIN);
1159         case CAM_REQ_INVALID:   /* CCB request was invalid */
1160                 return (EINVAL);
1161         case CAM_RESRC_UNAVAIL: /* Resource Unavailable */
1162                 return (ENOMEM);
1163         case CAM_BUSY:          /* CAM subsytem is busy */
1164         case CAM_UA_ABORT:      /* Unable to abort CCB request */
1165                 return (EBUSY);
1166         default:
1167                 return (ENXIO);
1168         }
1169 }
1170
1171 static size_t
1172 targccblen(xpt_opcode func_code)
1173 {
1174         int len;
1175
1176         /* Codes we expect to see as a target */
1177         switch (func_code) {
1178         case XPT_CONT_TARGET_IO:
1179         case XPT_SCSI_IO:
1180                 len = sizeof(struct ccb_scsiio);
1181                 break;
1182         case XPT_ACCEPT_TARGET_IO:
1183                 len = sizeof(struct ccb_accept_tio);
1184                 break;
1185         case XPT_IMMED_NOTIFY:
1186                 len = sizeof(struct ccb_immed_notify);
1187                 break;
1188         case XPT_REL_SIMQ:
1189                 len = sizeof(struct ccb_relsim);
1190                 break;
1191         case XPT_PATH_INQ:
1192                 len = sizeof(struct ccb_pathinq);
1193                 break;
1194         case XPT_DEBUG:
1195                 len = sizeof(struct ccb_debug);
1196                 break;
1197         case XPT_ABORT:
1198                 len = sizeof(struct ccb_abort);
1199                 break;
1200         case XPT_EN_LUN:
1201                 len = sizeof(struct ccb_en_lun);
1202                 break;
1203         default:
1204                 len = sizeof(union ccb);
1205                 break;
1206         }
1207
1208         return (len);
1209 }