Linux kernel & device driver programming

Cross-Referenced Linux and Device Driver Code

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Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  1 /*
  2  * SCSI Enclosure Services
  3  *
  4  * Copyright (C) 2008 James Bottomley <James.Bottomley@HansenPartnership.com>
  5  *
  6 **-----------------------------------------------------------------------------
  7 **
  8 **  This program is free software; you can redistribute it and/or
  9 **  modify it under the terms of the GNU General Public License
 10 **  version 2 as published by the Free Software Foundation.
 11 **
 12 **  This program is distributed in the hope that it will be useful,
 13 **  but WITHOUT ANY WARRANTY; without even the implied warranty of
 14 **  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15 **  GNU General Public License for more details.
 16 **
 17 **  You should have received a copy of the GNU General Public License
 18 **  along with this program; if not, write to the Free Software
 19 **  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 20 **
 21 **-----------------------------------------------------------------------------
 22 */
 23 
 24 #include <linux/module.h>
 25 #include <linux/kernel.h>
 26 #include <linux/enclosure.h>
 27 
 28 #include <scsi/scsi.h>
 29 #include <scsi/scsi_cmnd.h>
 30 #include <scsi/scsi_dbg.h>
 31 #include <scsi/scsi_device.h>
 32 #include <scsi/scsi_driver.h>
 33 #include <scsi/scsi_host.h>
 34 
 35 struct ses_device {
 36         unsigned char *page1;
 37         unsigned char *page2;
 38         unsigned char *page10;
 39         short page1_len;
 40         short page2_len;
 41         short page10_len;
 42 };
 43 
 44 struct ses_component {
 45         u64 addr;
 46         unsigned char *desc;
 47 };
 48 
 49 static int ses_probe(struct device *dev)
 50 {
 51         struct scsi_device *sdev = to_scsi_device(dev);
 52         int err = -ENODEV;
 53 
 54         if (sdev->type != TYPE_ENCLOSURE)
 55                 goto out;
 56 
 57         err = 0;
 58         sdev_printk(KERN_NOTICE, sdev, "Attached Enclosure device\n");
 59 
 60  out:
 61         return err;
 62 }
 63 
 64 #define SES_TIMEOUT (30 * HZ)
 65 #define SES_RETRIES 3
 66 
 67 static int ses_recv_diag(struct scsi_device *sdev, int page_code,
 68                          void *buf, int bufflen)
 69 {
 70         unsigned char cmd[] = {
 71                 RECEIVE_DIAGNOSTIC,
 72                 1,              /* Set PCV bit */
 73                 page_code,
 74                 bufflen >> 8,
 75                 bufflen & 0xff,
 76                 0
 77         };
 78 
 79         return scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buf, bufflen,
 80                                 NULL, SES_TIMEOUT, SES_RETRIES, NULL);
 81 }
 82 
 83 static int ses_send_diag(struct scsi_device *sdev, int page_code,
 84                          void *buf, int bufflen)
 85 {
 86         u32 result;
 87 
 88         unsigned char cmd[] = {
 89                 SEND_DIAGNOSTIC,
 90                 0x10,           /* Set PF bit */
 91                 0,
 92                 bufflen >> 8,
 93                 bufflen & 0xff,
 94                 0
 95         };
 96 
 97         result = scsi_execute_req(sdev, cmd, DMA_TO_DEVICE, buf, bufflen,
 98                                   NULL, SES_TIMEOUT, SES_RETRIES, NULL);
 99         if (result)
100                 sdev_printk(KERN_ERR, sdev, "SEND DIAGNOSTIC result: %8x\n",
101                             result);
102         return result;
103 }
104 
105 static int ses_set_page2_descriptor(struct enclosure_device *edev,
106                                       struct enclosure_component *ecomp,
107                                       unsigned char *desc)
108 {
109         int i, j, count = 0, descriptor = ecomp->number;
110         struct scsi_device *sdev = to_scsi_device(edev->edev.parent);
111         struct ses_device *ses_dev = edev->scratch;
112         unsigned char *type_ptr = ses_dev->page1 + 12 + ses_dev->page1[11];
113         unsigned char *desc_ptr = ses_dev->page2 + 8;
114 
115         /* Clear everything */
116         memset(desc_ptr, 0, ses_dev->page2_len - 8);
117         for (i = 0; i < ses_dev->page1[10]; i++, type_ptr += 4) {
118                 for (j = 0; j < type_ptr[1]; j++) {
119                         desc_ptr += 4;
120                         if (type_ptr[0] != ENCLOSURE_COMPONENT_DEVICE &&
121                             type_ptr[0] != ENCLOSURE_COMPONENT_ARRAY_DEVICE)
122                                 continue;
123                         if (count++ == descriptor) {
124                                 memcpy(desc_ptr, desc, 4);
125                                 /* set select */
126                                 desc_ptr[0] |= 0x80;
127                                 /* clear reserved, just in case */
128                                 desc_ptr[0] &= 0xf0;
129                         }
130                 }
131         }
132 
133         return ses_send_diag(sdev, 2, ses_dev->page2, ses_dev->page2_len);
134 }
135 
136 static unsigned char *ses_get_page2_descriptor(struct enclosure_device *edev,
137                                       struct enclosure_component *ecomp)
138 {
139         int i, j, count = 0, descriptor = ecomp->number;
140         struct scsi_device *sdev = to_scsi_device(edev->edev.parent);
141         struct ses_device *ses_dev = edev->scratch;
142         unsigned char *type_ptr = ses_dev->page1 + 12 + ses_dev->page1[11];
143         unsigned char *desc_ptr = ses_dev->page2 + 8;
144 
145         ses_recv_diag(sdev, 2, ses_dev->page2, ses_dev->page2_len);
146 
147         for (i = 0; i < ses_dev->page1[10]; i++, type_ptr += 4) {
148                 for (j = 0; j < type_ptr[1]; j++) {
149                         desc_ptr += 4;
150                         if (type_ptr[0] != ENCLOSURE_COMPONENT_DEVICE &&
151                             type_ptr[0] != ENCLOSURE_COMPONENT_ARRAY_DEVICE)
152                                 continue;
153                         if (count++ == descriptor)
154                                 return desc_ptr;
155                 }
156         }
157         return NULL;
158 }
159 
160 static void ses_get_fault(struct enclosure_device *edev,
161                           struct enclosure_component *ecomp)
162 {
163         unsigned char *desc;
164 
165         desc = ses_get_page2_descriptor(edev, ecomp);
166         if (desc)
167                 ecomp->fault = (desc[3] & 0x60) >> 4;
168 }
169 
170 static int ses_set_fault(struct enclosure_device *edev,
171                           struct enclosure_component *ecomp,
172                          enum enclosure_component_setting val)
173 {
174         unsigned char desc[4] = {0 };
175 
176         switch (val) {
177         case ENCLOSURE_SETTING_DISABLED:
178                 /* zero is disabled */
179                 break;
180         case ENCLOSURE_SETTING_ENABLED:
181                 desc[2] = 0x02;
182                 break;
183         default:
184                 /* SES doesn't do the SGPIO blink settings */
185                 return -EINVAL;
186         }
187 
188         return ses_set_page2_descriptor(edev, ecomp, desc);
189 }
190 
191 static void ses_get_status(struct enclosure_device *edev,
192                            struct enclosure_component *ecomp)
193 {
194         unsigned char *desc;
195 
196         desc = ses_get_page2_descriptor(edev, ecomp);
197         if (desc)
198                 ecomp->status = (desc[0] & 0x0f);
199 }
200 
201 static void ses_get_locate(struct enclosure_device *edev,
202                            struct enclosure_component *ecomp)
203 {
204         unsigned char *desc;
205 
206         desc = ses_get_page2_descriptor(edev, ecomp);
207         if (desc)
208                 ecomp->locate = (desc[2] & 0x02) ? 1 : 0;
209 }
210 
211 static int ses_set_locate(struct enclosure_device *edev,
212                           struct enclosure_component *ecomp,
213                           enum enclosure_component_setting val)
214 {
215         unsigned char desc[4] = {0 };
216 
217         switch (val) {
218         case ENCLOSURE_SETTING_DISABLED:
219                 /* zero is disabled */
220                 break;
221         case ENCLOSURE_SETTING_ENABLED:
222                 desc[2] = 0x02;
223                 break;
224         default:
225                 /* SES doesn't do the SGPIO blink settings */
226                 return -EINVAL;
227         }
228         return ses_set_page2_descriptor(edev, ecomp, desc);
229 }
230 
231 static int ses_set_active(struct enclosure_device *edev,
232                           struct enclosure_component *ecomp,
233                           enum enclosure_component_setting val)
234 {
235         unsigned char desc[4] = {0 };
236 
237         switch (val) {
238         case ENCLOSURE_SETTING_DISABLED:
239                 /* zero is disabled */
240                 ecomp->active = 0;
241                 break;
242         case ENCLOSURE_SETTING_ENABLED:
243                 desc[2] = 0x80;
244                 ecomp->active = 1;
245                 break;
246         default:
247                 /* SES doesn't do the SGPIO blink settings */
248                 return -EINVAL;
249         }
250         return ses_set_page2_descriptor(edev, ecomp, desc);
251 }
252 
253 static struct enclosure_component_callbacks ses_enclosure_callbacks = {
254         .get_fault              = ses_get_fault,
255         .set_fault              = ses_set_fault,
256         .get_status             = ses_get_status,
257         .get_locate             = ses_get_locate,
258         .set_locate             = ses_set_locate,
259         .set_active             = ses_set_active,
260 };
261 
262 struct ses_host_edev {
263         struct Scsi_Host *shost;
264         struct enclosure_device *edev;
265 };
266 
267 #if 0
268 int ses_match_host(struct enclosure_device *edev, void *data)
269 {
270         struct ses_host_edev *sed = data;
271         struct scsi_device *sdev;
272 
273         if (!scsi_is_sdev_device(edev->edev.parent))
274                 return 0;
275 
276         sdev = to_scsi_device(edev->edev.parent);
277 
278         if (sdev->host != sed->shost)
279                 return 0;
280 
281         sed->edev = edev;
282         return 1;
283 }
284 #endif  /*  0  */
285 
286 static void ses_process_descriptor(struct enclosure_component *ecomp,
287                                    unsigned char *desc)
288 {
289         int eip = desc[0] & 0x10;
290         int invalid = desc[0] & 0x80;
291         enum scsi_protocol proto = desc[0] & 0x0f;
292         u64 addr = 0;
293         struct ses_component *scomp = ecomp->scratch;
294         unsigned char *d;
295 
296         scomp->desc = desc;
297 
298         if (invalid)
299                 return;
300 
301         switch (proto) {
302         case SCSI_PROTOCOL_SAS:
303                 if (eip)
304                         d = desc + 8;
305                 else
306                         d = desc + 4;
307                 /* only take the phy0 addr */
308                 addr = (u64)d[12] << 56 |
309                         (u64)d[13] << 48 |
310                         (u64)d[14] << 40 |
311                         (u64)d[15] << 32 |
312                         (u64)d[16] << 24 |
313                         (u64)d[17] << 16 |
314                         (u64)d[18] << 8 |
315                         (u64)d[19];
316                 break;
317         default:
318                 /* FIXME: Need to add more protocols than just SAS */
319                 break;
320         }
321         scomp->addr = addr;
322 }
323 
324 struct efd {
325         u64 addr;
326         struct device *dev;
327 };
328 
329 static int ses_enclosure_find_by_addr(struct enclosure_device *edev,
330                                       void *data)
331 {
332         struct efd *efd = data;
333         int i;
334         struct ses_component *scomp;
335 
336         if (!edev->component[0].scratch)
337                 return 0;
338 
339         for (i = 0; i < edev->components; i++) {
340                 scomp = edev->component[i].scratch;
341                 if (scomp->addr != efd->addr)
342                         continue;
343 
344                 enclosure_add_device(edev, i, efd->dev);
345                 return 1;
346         }
347         return 0;
348 }
349 
350 static void ses_match_to_enclosure(struct enclosure_device *edev,
351                                    struct scsi_device *sdev)
352 {
353         unsigned char *buf;
354         unsigned char *desc;
355         unsigned int vpd_len;
356         struct efd efd = {
357                 .addr = 0,
358         };
359 
360         buf = scsi_get_vpd_page(sdev, 0x83);
361         if (!buf)
362                 return;
363 
364         vpd_len = ((buf[2] << 8) | buf[3]) + 4;
365 
366         desc = buf + 4;
367         while (desc < buf + vpd_len) {
368                 enum scsi_protocol proto = desc[0] >> 4;
369                 u8 code_set = desc[0] & 0x0f;
370                 u8 piv = desc[1] & 0x80;
371                 u8 assoc = (desc[1] & 0x30) >> 4;
372                 u8 type = desc[1] & 0x0f;
373                 u8 len = desc[3];
374 
375                 if (piv && code_set == 1 && assoc == 1
376                     && proto == SCSI_PROTOCOL_SAS && type == 3 && len == 8)
377                         efd.addr = (u64)desc[4] << 56 |
378                                 (u64)desc[5] << 48 |
379                                 (u64)desc[6] << 40 |
380                                 (u64)desc[7] << 32 |
381                                 (u64)desc[8] << 24 |
382                                 (u64)desc[9] << 16 |
383                                 (u64)desc[10] << 8 |
384                                 (u64)desc[11];
385 
386                 desc += len + 4;
387         }
388         if (!efd.addr)
389                 goto free;
390 
391         efd.dev = &sdev->sdev_gendev;
392 
393         enclosure_for_each_device(ses_enclosure_find_by_addr, &efd);
394  free:
395         kfree(buf);
396 }
397 
398 #define INIT_ALLOC_SIZE 32
399 
400 static int ses_intf_add(struct device *cdev,
401                         struct class_interface *intf)
402 {
403         struct scsi_device *sdev = to_scsi_device(cdev->parent);
404         struct scsi_device *tmp_sdev;
405         unsigned char *buf = NULL, *hdr_buf, *type_ptr, *desc_ptr = NULL,
406                 *addl_desc_ptr = NULL;
407         struct ses_device *ses_dev;
408         u32 result;
409         int i, j, types, len, page7_len = 0, components = 0;
410         int err = -ENOMEM;
411         struct enclosure_device *edev;
412         struct ses_component *scomp = NULL;
413 
414         if (!scsi_device_enclosure(sdev)) {
415                 /* not an enclosure, but might be in one */
416                 edev = enclosure_find(&sdev->host->shost_gendev);
417                 if (edev) {
418                         ses_match_to_enclosure(edev, sdev);
419                         put_device(&edev->edev);
420                 }
421                 return -ENODEV;
422         }
423 
424         /* TYPE_ENCLOSURE prints a message in probe */
425         if (sdev->type != TYPE_ENCLOSURE)
426                 sdev_printk(KERN_NOTICE, sdev, "Embedded Enclosure Device\n");
427 
428         ses_dev = kzalloc(sizeof(*ses_dev), GFP_KERNEL);
429         hdr_buf = kzalloc(INIT_ALLOC_SIZE, GFP_KERNEL);
430         if (!hdr_buf || !ses_dev)
431                 goto err_init_free;
432 
433         result = ses_recv_diag(sdev, 1, hdr_buf, INIT_ALLOC_SIZE);
434         if (result)
435                 goto recv_failed;
436 
437         if (hdr_buf[1] != 0) {
438                 /* FIXME: need subenclosure support; I've just never
439                  * seen a device with subenclosures and it makes the
440                  * traversal routines more complex */
441                 sdev_printk(KERN_ERR, sdev,
442                         "FIXME driver has no support for subenclosures (%d)\n",
443                         hdr_buf[1]);
444                 goto err_free;
445         }
446 
447         len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
448         buf = kzalloc(len, GFP_KERNEL);
449         if (!buf)
450                 goto err_free;
451 
452         result = ses_recv_diag(sdev, 1, buf, len);
453         if (result)
454                 goto recv_failed;
455 
456         types = buf[10];
457 
458         type_ptr = buf + 12 + buf[11];
459 
460         for (i = 0; i < types; i++, type_ptr += 4) {
461                 if (type_ptr[0] == ENCLOSURE_COMPONENT_DEVICE ||
462                     type_ptr[0] == ENCLOSURE_COMPONENT_ARRAY_DEVICE)
463                         components += type_ptr[1];
464         }
465         ses_dev->page1 = buf;
466         ses_dev->page1_len = len;
467         buf = NULL;
468 
469         result = ses_recv_diag(sdev, 2, hdr_buf, INIT_ALLOC_SIZE);
470         if (result)
471                 goto recv_failed;
472 
473         len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
474         buf = kzalloc(len, GFP_KERNEL);
475         if (!buf)
476                 goto err_free;
477 
478         /* make sure getting page 2 actually works */
479         result = ses_recv_diag(sdev, 2, buf, len);
480         if (result)
481                 goto recv_failed;
482         ses_dev->page2 = buf;
483         ses_dev->page2_len = len;
484         buf = NULL;
485 
486         /* The additional information page --- allows us
487          * to match up the devices */
488         result = ses_recv_diag(sdev, 10, hdr_buf, INIT_ALLOC_SIZE);
489         if (!result) {
490 
491                 len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
492                 buf = kzalloc(len, GFP_KERNEL);
493                 if (!buf)
494                         goto err_free;
495 
496                 result = ses_recv_diag(sdev, 10, buf, len);
497                 if (result)
498                         goto recv_failed;
499                 ses_dev->page10 = buf;
500                 ses_dev->page10_len = len;
501                 buf = NULL;
502         }
503 
504         scomp = kzalloc(sizeof(struct ses_component) * components, GFP_KERNEL);
505         if (!scomp)
506                 goto err_free;
507 
508         edev = enclosure_register(cdev->parent, dev_name(&sdev->sdev_gendev),
509                                   components, &ses_enclosure_callbacks);
510         if (IS_ERR(edev)) {
511                 err = PTR_ERR(edev);
512                 goto err_free;
513         }
514 
515         edev->scratch = ses_dev;
516         for (i = 0; i < components; i++)
517                 edev->component[i].scratch = scomp + i;
518 
519         /* Page 7 for the descriptors is optional */
520         result = ses_recv_diag(sdev, 7, hdr_buf, INIT_ALLOC_SIZE);
521         if (result)
522                 goto simple_populate;
523 
524         page7_len = len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
525         /* add 1 for trailing '\0' we'll use */
526         buf = kzalloc(len + 1, GFP_KERNEL);
527         if (!buf)
528                 goto simple_populate;
529         result = ses_recv_diag(sdev, 7, buf, len);
530         if (result) {
531  simple_populate:
532                 kfree(buf);
533                 buf = NULL;
534                 desc_ptr = NULL;
535                 addl_desc_ptr = NULL;
536         } else {
537                 desc_ptr = buf + 8;
538                 len = (desc_ptr[2] << 8) + desc_ptr[3];
539                 /* skip past overall descriptor */
540                 desc_ptr += len + 4;
541                 if (ses_dev->page10)
542                         addl_desc_ptr = ses_dev->page10 + 8;
543         }
544         type_ptr = ses_dev->page1 + 12 + ses_dev->page1[11];
545         components = 0;
546         for (i = 0; i < types; i++, type_ptr += 4) {
547                 for (j = 0; j < type_ptr[1]; j++) {
548                         char *name = NULL;
549                         struct enclosure_component *ecomp;
550 
551                         if (desc_ptr) {
552                                 if (desc_ptr >= buf + page7_len) {
553                                         desc_ptr = NULL;
554                                 } else {
555                                         len = (desc_ptr[2] << 8) + desc_ptr[3];
556                                         desc_ptr += 4;
557                                         /* Add trailing zero - pushes into
558                                          * reserved space */
559                                         desc_ptr[len] = '\0';
560                                         name = desc_ptr;
561                                 }
562                         }
563                         if (type_ptr[0] == ENCLOSURE_COMPONENT_DEVICE ||
564                             type_ptr[0] == ENCLOSURE_COMPONENT_ARRAY_DEVICE) {
565 
566                                 ecomp = enclosure_component_register(edev,
567                                                              components++,
568                                                              type_ptr[0],
569                                                              name);
570 
571                                 if (!IS_ERR(ecomp) && addl_desc_ptr)
572                                         ses_process_descriptor(ecomp,
573                                                                addl_desc_ptr);
574                         }
575                         if (desc_ptr)
576                                 desc_ptr += len;
577 
578                         if (addl_desc_ptr)
579                                 addl_desc_ptr += addl_desc_ptr[1] + 2;
580 
581                 }
582         }
583         kfree(buf);
584         kfree(hdr_buf);
585 
586         /* see if there are any devices matching before
587          * we found the enclosure */
588         shost_for_each_device(tmp_sdev, sdev->host) {
589                 if (tmp_sdev->lun != 0 || scsi_device_enclosure(tmp_sdev))
590                         continue;
591                 ses_match_to_enclosure(edev, tmp_sdev);
592         }
593 
594         return 0;
595 
596  recv_failed:
597         sdev_printk(KERN_ERR, sdev, "Failed to get diagnostic page 0x%x\n",
598                     result);
599         err = -ENODEV;
600  err_free:
601         kfree(buf);
602         kfree(scomp);
603         kfree(ses_dev->page10);
604         kfree(ses_dev->page2);
605         kfree(ses_dev->page1);
606  err_init_free:
607         kfree(ses_dev);
608         kfree(hdr_buf);
609         sdev_printk(KERN_ERR, sdev, "Failed to bind enclosure %d\n", err);
610         return err;
611 }
612 
613 static int ses_remove(struct device *dev)
614 {
615         return 0;
616 }
617 
618 static void ses_intf_remove(struct device *cdev,
619                             struct class_interface *intf)
620 {
621         struct scsi_device *sdev = to_scsi_device(cdev->parent);
622         struct enclosure_device *edev;
623         struct ses_device *ses_dev;
624 
625         if (!scsi_device_enclosure(sdev))
626                 return;
627 
628         edev = enclosure_find(cdev->parent);
629         if (!edev)
630                 return;
631 
632         ses_dev = edev->scratch;
633         edev->scratch = NULL;
634 
635         kfree(ses_dev->page10);
636         kfree(ses_dev->page1);
637         kfree(ses_dev->page2);
638         kfree(ses_dev);
639 
640         kfree(edev->component[0].scratch);
641 
642         put_device(&edev->edev);
643         enclosure_unregister(edev);
644 }
645 
646 static struct class_interface ses_interface = {
647         .add_dev        = ses_intf_add,
648         .remove_dev     = ses_intf_remove,
649 };
650 
651 static struct scsi_driver ses_template = {
652         .owner                  = THIS_MODULE,
653         .gendrv = {
654                 .name           = "ses",
655                 .probe          = ses_probe,
656                 .remove         = ses_remove,
657         },
658 };
659 
660 static int __init ses_init(void)
661 {
662         int err;
663 
664         err = scsi_register_interface(&ses_interface);
665         if (err)
666                 return err;
667 
668         err = scsi_register_driver(&ses_template.gendrv);
669         if (err)
670                 goto out_unreg;
671 
672         return 0;
673 
674  out_unreg:
675         scsi_unregister_interface(&ses_interface);
676         return err;
677 }
678 
679 static void __exit ses_exit(void)
680 {
681         scsi_unregister_driver(&ses_template.gendrv);
682         scsi_unregister_interface(&ses_interface);
683 }
684 
685 module_init(ses_init);
686 module_exit(ses_exit);
687 
688 MODULE_ALIAS_SCSI_DEVICE(TYPE_ENCLOSURE);
689 
690 MODULE_AUTHOR("James Bottomley");
691 MODULE_DESCRIPTION("SCSI Enclosure Services (ses) driver");
692 MODULE_LICENSE("GPL v2");
693 
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