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