ath5k: fix values for bus error bits in ISR2
[linux-2.6/next.git] / drivers / s390 / char / tape_core.c
blob1d420d9475961719ecd625a5fab7c06f5a2713bd
1 /*
2 * drivers/s390/char/tape_core.c
3 * basic function of the tape device driver
5 * S390 and zSeries version
6 * Copyright IBM Corp. 2001, 2009
7 * Author(s): Carsten Otte <cotte@de.ibm.com>
8 * Michael Holzheu <holzheu@de.ibm.com>
9 * Tuan Ngo-Anh <ngoanh@de.ibm.com>
10 * Martin Schwidefsky <schwidefsky@de.ibm.com>
11 * Stefan Bader <shbader@de.ibm.com>
14 #define KMSG_COMPONENT "tape"
15 #include <linux/module.h>
16 #include <linux/init.h> // for kernel parameters
17 #include <linux/kmod.h> // for requesting modules
18 #include <linux/spinlock.h> // for locks
19 #include <linux/vmalloc.h>
20 #include <linux/list.h>
22 #include <asm/types.h> // for variable types
24 #define TAPE_DBF_AREA tape_core_dbf
26 #include "tape.h"
27 #include "tape_std.h"
29 #define LONG_BUSY_TIMEOUT 180 /* seconds */
31 static void __tape_do_irq (struct ccw_device *, unsigned long, struct irb *);
32 static void tape_delayed_next_request(struct work_struct *);
33 static void tape_long_busy_timeout(unsigned long data);
36 * One list to contain all tape devices of all disciplines, so
37 * we can assign the devices to minor numbers of the same major
38 * The list is protected by the rwlock
40 static LIST_HEAD(tape_device_list);
41 static DEFINE_RWLOCK(tape_device_lock);
44 * Pointer to debug area.
46 debug_info_t *TAPE_DBF_AREA = NULL;
47 EXPORT_SYMBOL(TAPE_DBF_AREA);
50 * Printable strings for tape enumerations.
52 const char *tape_state_verbose[TS_SIZE] =
54 [TS_UNUSED] = "UNUSED",
55 [TS_IN_USE] = "IN_USE",
56 [TS_BLKUSE] = "BLKUSE",
57 [TS_INIT] = "INIT ",
58 [TS_NOT_OPER] = "NOT_OP"
61 const char *tape_op_verbose[TO_SIZE] =
63 [TO_BLOCK] = "BLK", [TO_BSB] = "BSB",
64 [TO_BSF] = "BSF", [TO_DSE] = "DSE",
65 [TO_FSB] = "FSB", [TO_FSF] = "FSF",
66 [TO_LBL] = "LBL", [TO_NOP] = "NOP",
67 [TO_RBA] = "RBA", [TO_RBI] = "RBI",
68 [TO_RFO] = "RFO", [TO_REW] = "REW",
69 [TO_RUN] = "RUN", [TO_WRI] = "WRI",
70 [TO_WTM] = "WTM", [TO_MSEN] = "MSN",
71 [TO_LOAD] = "LOA", [TO_READ_CONFIG] = "RCF",
72 [TO_READ_ATTMSG] = "RAT",
73 [TO_DIS] = "DIS", [TO_ASSIGN] = "ASS",
74 [TO_UNASSIGN] = "UAS", [TO_CRYPT_ON] = "CON",
75 [TO_CRYPT_OFF] = "COF", [TO_KEKL_SET] = "KLS",
76 [TO_KEKL_QUERY] = "KLQ",[TO_RDC] = "RDC",
79 static int devid_to_int(struct ccw_dev_id *dev_id)
81 return dev_id->devno + (dev_id->ssid << 16);
85 * Some channel attached tape specific attributes.
87 * FIXME: In the future the first_minor and blocksize attribute should be
88 * replaced by a link to the cdev tree.
90 static ssize_t
91 tape_medium_state_show(struct device *dev, struct device_attribute *attr, char *buf)
93 struct tape_device *tdev;
95 tdev = dev_get_drvdata(dev);
96 return scnprintf(buf, PAGE_SIZE, "%i\n", tdev->medium_state);
99 static
100 DEVICE_ATTR(medium_state, 0444, tape_medium_state_show, NULL);
102 static ssize_t
103 tape_first_minor_show(struct device *dev, struct device_attribute *attr, char *buf)
105 struct tape_device *tdev;
107 tdev = dev_get_drvdata(dev);
108 return scnprintf(buf, PAGE_SIZE, "%i\n", tdev->first_minor);
111 static
112 DEVICE_ATTR(first_minor, 0444, tape_first_minor_show, NULL);
114 static ssize_t
115 tape_state_show(struct device *dev, struct device_attribute *attr, char *buf)
117 struct tape_device *tdev;
119 tdev = dev_get_drvdata(dev);
120 return scnprintf(buf, PAGE_SIZE, "%s\n", (tdev->first_minor < 0) ?
121 "OFFLINE" : tape_state_verbose[tdev->tape_state]);
124 static
125 DEVICE_ATTR(state, 0444, tape_state_show, NULL);
127 static ssize_t
128 tape_operation_show(struct device *dev, struct device_attribute *attr, char *buf)
130 struct tape_device *tdev;
131 ssize_t rc;
133 tdev = dev_get_drvdata(dev);
134 if (tdev->first_minor < 0)
135 return scnprintf(buf, PAGE_SIZE, "N/A\n");
137 spin_lock_irq(get_ccwdev_lock(tdev->cdev));
138 if (list_empty(&tdev->req_queue))
139 rc = scnprintf(buf, PAGE_SIZE, "---\n");
140 else {
141 struct tape_request *req;
143 req = list_entry(tdev->req_queue.next, struct tape_request,
144 list);
145 rc = scnprintf(buf,PAGE_SIZE, "%s\n", tape_op_verbose[req->op]);
147 spin_unlock_irq(get_ccwdev_lock(tdev->cdev));
148 return rc;
151 static
152 DEVICE_ATTR(operation, 0444, tape_operation_show, NULL);
154 static ssize_t
155 tape_blocksize_show(struct device *dev, struct device_attribute *attr, char *buf)
157 struct tape_device *tdev;
159 tdev = dev_get_drvdata(dev);
161 return scnprintf(buf, PAGE_SIZE, "%i\n", tdev->char_data.block_size);
164 static
165 DEVICE_ATTR(blocksize, 0444, tape_blocksize_show, NULL);
167 static struct attribute *tape_attrs[] = {
168 &dev_attr_medium_state.attr,
169 &dev_attr_first_minor.attr,
170 &dev_attr_state.attr,
171 &dev_attr_operation.attr,
172 &dev_attr_blocksize.attr,
173 NULL
176 static struct attribute_group tape_attr_group = {
177 .attrs = tape_attrs,
181 * Tape state functions
183 void
184 tape_state_set(struct tape_device *device, enum tape_state newstate)
186 const char *str;
188 if (device->tape_state == TS_NOT_OPER) {
189 DBF_EVENT(3, "ts_set err: not oper\n");
190 return;
192 DBF_EVENT(4, "ts. dev: %x\n", device->first_minor);
193 DBF_EVENT(4, "old ts:\t\n");
194 if (device->tape_state < TS_SIZE && device->tape_state >=0 )
195 str = tape_state_verbose[device->tape_state];
196 else
197 str = "UNKNOWN TS";
198 DBF_EVENT(4, "%s\n", str);
199 DBF_EVENT(4, "new ts:\t\n");
200 if (newstate < TS_SIZE && newstate >= 0)
201 str = tape_state_verbose[newstate];
202 else
203 str = "UNKNOWN TS";
204 DBF_EVENT(4, "%s\n", str);
205 device->tape_state = newstate;
206 wake_up(&device->state_change_wq);
209 void
210 tape_med_state_set(struct tape_device *device, enum tape_medium_state newstate)
212 if (device->medium_state == newstate)
213 return;
214 switch(newstate){
215 case MS_UNLOADED:
216 device->tape_generic_status |= GMT_DR_OPEN(~0);
217 dev_info(&device->cdev->dev, "The tape cartridge has been "
218 "successfully unloaded\n");
219 break;
220 case MS_LOADED:
221 device->tape_generic_status &= ~GMT_DR_OPEN(~0);
222 dev_info(&device->cdev->dev, "A tape cartridge has been "
223 "mounted\n");
224 break;
225 default:
226 // print nothing
227 break;
229 device->medium_state = newstate;
230 wake_up(&device->state_change_wq);
234 * Stop running ccw. Has to be called with the device lock held.
236 static int
237 __tape_cancel_io(struct tape_device *device, struct tape_request *request)
239 int retries;
240 int rc;
242 /* Check if interrupt has already been processed */
243 if (request->callback == NULL)
244 return 0;
246 rc = 0;
247 for (retries = 0; retries < 5; retries++) {
248 rc = ccw_device_clear(device->cdev, (long) request);
250 switch (rc) {
251 case 0:
252 request->status = TAPE_REQUEST_DONE;
253 return 0;
254 case -EBUSY:
255 request->status = TAPE_REQUEST_CANCEL;
256 schedule_delayed_work(&device->tape_dnr, 0);
257 return 0;
258 case -ENODEV:
259 DBF_EXCEPTION(2, "device gone, retry\n");
260 break;
261 case -EIO:
262 DBF_EXCEPTION(2, "I/O error, retry\n");
263 break;
264 default:
265 BUG();
269 return rc;
273 * Add device into the sorted list, giving it the first
274 * available minor number.
276 static int
277 tape_assign_minor(struct tape_device *device)
279 struct tape_device *tmp;
280 int minor;
282 minor = 0;
283 write_lock(&tape_device_lock);
284 list_for_each_entry(tmp, &tape_device_list, node) {
285 if (minor < tmp->first_minor)
286 break;
287 minor += TAPE_MINORS_PER_DEV;
289 if (minor >= 256) {
290 write_unlock(&tape_device_lock);
291 return -ENODEV;
293 device->first_minor = minor;
294 list_add_tail(&device->node, &tmp->node);
295 write_unlock(&tape_device_lock);
296 return 0;
299 /* remove device from the list */
300 static void
301 tape_remove_minor(struct tape_device *device)
303 write_lock(&tape_device_lock);
304 list_del_init(&device->node);
305 device->first_minor = -1;
306 write_unlock(&tape_device_lock);
310 * Set a device online.
312 * This function is called by the common I/O layer to move a device from the
313 * detected but offline into the online state.
314 * If we return an error (RC < 0) the device remains in the offline state. This
315 * can happen if the device is assigned somewhere else, for example.
318 tape_generic_online(struct tape_device *device,
319 struct tape_discipline *discipline)
321 int rc;
323 DBF_LH(6, "tape_enable_device(%p, %p)\n", device, discipline);
325 if (device->tape_state != TS_INIT) {
326 DBF_LH(3, "Tapestate not INIT (%d)\n", device->tape_state);
327 return -EINVAL;
330 init_timer(&device->lb_timeout);
331 device->lb_timeout.function = tape_long_busy_timeout;
333 /* Let the discipline have a go at the device. */
334 device->discipline = discipline;
335 if (!try_module_get(discipline->owner)) {
336 return -EINVAL;
339 rc = discipline->setup_device(device);
340 if (rc)
341 goto out;
342 rc = tape_assign_minor(device);
343 if (rc)
344 goto out_discipline;
346 rc = tapechar_setup_device(device);
347 if (rc)
348 goto out_minor;
349 rc = tapeblock_setup_device(device);
350 if (rc)
351 goto out_char;
353 tape_state_set(device, TS_UNUSED);
355 DBF_LH(3, "(%08x): Drive set online\n", device->cdev_id);
357 return 0;
359 out_char:
360 tapechar_cleanup_device(device);
361 out_discipline:
362 device->discipline->cleanup_device(device);
363 device->discipline = NULL;
364 out_minor:
365 tape_remove_minor(device);
366 out:
367 module_put(discipline->owner);
368 return rc;
371 static void
372 tape_cleanup_device(struct tape_device *device)
374 tapeblock_cleanup_device(device);
375 tapechar_cleanup_device(device);
376 device->discipline->cleanup_device(device);
377 module_put(device->discipline->owner);
378 tape_remove_minor(device);
379 tape_med_state_set(device, MS_UNKNOWN);
383 * Suspend device.
385 * Called by the common I/O layer if the drive should be suspended on user
386 * request. We refuse to suspend if the device is loaded or in use for the
387 * following reason:
388 * While the Linux guest is suspended, it might be logged off which causes
389 * devices to be detached. Tape devices are automatically rewound and unloaded
390 * during DETACH processing (unless the tape device was attached with the
391 * NOASSIGN or MULTIUSER option). After rewind/unload, there is no way to
392 * resume the original state of the tape device, since we would need to
393 * manually re-load the cartridge which was active at suspend time.
395 int tape_generic_pm_suspend(struct ccw_device *cdev)
397 struct tape_device *device;
399 device = dev_get_drvdata(&cdev->dev);
400 if (!device) {
401 return -ENODEV;
404 DBF_LH(3, "(%08x): tape_generic_pm_suspend(%p)\n",
405 device->cdev_id, device);
407 if (device->medium_state != MS_UNLOADED) {
408 pr_err("A cartridge is loaded in tape device %s, "
409 "refusing to suspend\n", dev_name(&cdev->dev));
410 return -EBUSY;
413 spin_lock_irq(get_ccwdev_lock(device->cdev));
414 switch (device->tape_state) {
415 case TS_INIT:
416 case TS_NOT_OPER:
417 case TS_UNUSED:
418 spin_unlock_irq(get_ccwdev_lock(device->cdev));
419 break;
420 default:
421 pr_err("Tape device %s is busy, refusing to "
422 "suspend\n", dev_name(&cdev->dev));
423 spin_unlock_irq(get_ccwdev_lock(device->cdev));
424 return -EBUSY;
427 DBF_LH(3, "(%08x): Drive suspended.\n", device->cdev_id);
428 return 0;
432 * Set device offline.
434 * Called by the common I/O layer if the drive should set offline on user
435 * request. We may prevent this by returning an error.
436 * Manual offline is only allowed while the drive is not in use.
439 tape_generic_offline(struct ccw_device *cdev)
441 struct tape_device *device;
443 device = dev_get_drvdata(&cdev->dev);
444 if (!device) {
445 return -ENODEV;
448 DBF_LH(3, "(%08x): tape_generic_offline(%p)\n",
449 device->cdev_id, device);
451 spin_lock_irq(get_ccwdev_lock(device->cdev));
452 switch (device->tape_state) {
453 case TS_INIT:
454 case TS_NOT_OPER:
455 spin_unlock_irq(get_ccwdev_lock(device->cdev));
456 break;
457 case TS_UNUSED:
458 tape_state_set(device, TS_INIT);
459 spin_unlock_irq(get_ccwdev_lock(device->cdev));
460 tape_cleanup_device(device);
461 break;
462 default:
463 DBF_EVENT(3, "(%08x): Set offline failed "
464 "- drive in use.\n",
465 device->cdev_id);
466 spin_unlock_irq(get_ccwdev_lock(device->cdev));
467 return -EBUSY;
470 DBF_LH(3, "(%08x): Drive set offline.\n", device->cdev_id);
471 return 0;
475 * Allocate memory for a new device structure.
477 static struct tape_device *
478 tape_alloc_device(void)
480 struct tape_device *device;
482 device = kzalloc(sizeof(struct tape_device), GFP_KERNEL);
483 if (device == NULL) {
484 DBF_EXCEPTION(2, "ti:no mem\n");
485 return ERR_PTR(-ENOMEM);
487 device->modeset_byte = kmalloc(1, GFP_KERNEL | GFP_DMA);
488 if (device->modeset_byte == NULL) {
489 DBF_EXCEPTION(2, "ti:no mem\n");
490 kfree(device);
491 return ERR_PTR(-ENOMEM);
493 INIT_LIST_HEAD(&device->req_queue);
494 INIT_LIST_HEAD(&device->node);
495 init_waitqueue_head(&device->state_change_wq);
496 init_waitqueue_head(&device->wait_queue);
497 device->tape_state = TS_INIT;
498 device->medium_state = MS_UNKNOWN;
499 *device->modeset_byte = 0;
500 device->first_minor = -1;
501 atomic_set(&device->ref_count, 1);
502 INIT_DELAYED_WORK(&device->tape_dnr, tape_delayed_next_request);
504 return device;
508 * Get a reference to an existing device structure. This will automatically
509 * increment the reference count.
511 struct tape_device *
512 tape_get_device_reference(struct tape_device *device)
514 DBF_EVENT(4, "tape_get_device_reference(%p) = %i\n", device,
515 atomic_inc_return(&device->ref_count));
517 return device;
521 * Decrease the reference counter of a devices structure. If the
522 * reference counter reaches zero free the device structure.
523 * The function returns a NULL pointer to be used by the caller
524 * for clearing reference pointers.
526 struct tape_device *
527 tape_put_device(struct tape_device *device)
529 int remain;
531 remain = atomic_dec_return(&device->ref_count);
532 if (remain > 0) {
533 DBF_EVENT(4, "tape_put_device(%p) -> %i\n", device, remain);
534 } else {
535 if (remain < 0) {
536 DBF_EVENT(4, "put device without reference\n");
537 } else {
538 DBF_EVENT(4, "tape_free_device(%p)\n", device);
539 kfree(device->modeset_byte);
540 kfree(device);
544 return NULL;
548 * Find tape device by a device index.
550 struct tape_device *
551 tape_get_device(int devindex)
553 struct tape_device *device, *tmp;
555 device = ERR_PTR(-ENODEV);
556 read_lock(&tape_device_lock);
557 list_for_each_entry(tmp, &tape_device_list, node) {
558 if (tmp->first_minor / TAPE_MINORS_PER_DEV == devindex) {
559 device = tape_get_device_reference(tmp);
560 break;
563 read_unlock(&tape_device_lock);
564 return device;
568 * Driverfs tape probe function.
571 tape_generic_probe(struct ccw_device *cdev)
573 struct tape_device *device;
574 int ret;
575 struct ccw_dev_id dev_id;
577 device = tape_alloc_device();
578 if (IS_ERR(device))
579 return -ENODEV;
580 ccw_device_set_options(cdev, CCWDEV_DO_PATHGROUP);
581 ret = sysfs_create_group(&cdev->dev.kobj, &tape_attr_group);
582 if (ret) {
583 tape_put_device(device);
584 return ret;
586 dev_set_drvdata(&cdev->dev, device);
587 cdev->handler = __tape_do_irq;
588 device->cdev = cdev;
589 ccw_device_get_id(cdev, &dev_id);
590 device->cdev_id = devid_to_int(&dev_id);
591 return ret;
594 static void
595 __tape_discard_requests(struct tape_device *device)
597 struct tape_request * request;
598 struct list_head * l, *n;
600 list_for_each_safe(l, n, &device->req_queue) {
601 request = list_entry(l, struct tape_request, list);
602 if (request->status == TAPE_REQUEST_IN_IO)
603 request->status = TAPE_REQUEST_DONE;
604 list_del(&request->list);
606 /* Decrease ref_count for removed request. */
607 request->device = tape_put_device(device);
608 request->rc = -EIO;
609 if (request->callback != NULL)
610 request->callback(request, request->callback_data);
615 * Driverfs tape remove function.
617 * This function is called whenever the common I/O layer detects the device
618 * gone. This can happen at any time and we cannot refuse.
620 void
621 tape_generic_remove(struct ccw_device *cdev)
623 struct tape_device * device;
625 device = dev_get_drvdata(&cdev->dev);
626 if (!device) {
627 return;
629 DBF_LH(3, "(%08x): tape_generic_remove(%p)\n", device->cdev_id, cdev);
631 spin_lock_irq(get_ccwdev_lock(device->cdev));
632 switch (device->tape_state) {
633 case TS_INIT:
634 tape_state_set(device, TS_NOT_OPER);
635 case TS_NOT_OPER:
637 * Nothing to do.
639 spin_unlock_irq(get_ccwdev_lock(device->cdev));
640 break;
641 case TS_UNUSED:
643 * Need only to release the device.
645 tape_state_set(device, TS_NOT_OPER);
646 spin_unlock_irq(get_ccwdev_lock(device->cdev));
647 tape_cleanup_device(device);
648 break;
649 default:
651 * There may be requests on the queue. We will not get
652 * an interrupt for a request that was running. So we
653 * just post them all as I/O errors.
655 DBF_EVENT(3, "(%08x): Drive in use vanished!\n",
656 device->cdev_id);
657 dev_warn(&device->cdev->dev, "A tape unit was detached"
658 " while in use\n");
659 tape_state_set(device, TS_NOT_OPER);
660 __tape_discard_requests(device);
661 spin_unlock_irq(get_ccwdev_lock(device->cdev));
662 tape_cleanup_device(device);
665 if (!dev_get_drvdata(&cdev->dev)) {
666 sysfs_remove_group(&cdev->dev.kobj, &tape_attr_group);
667 dev_set_drvdata(&cdev->dev, tape_put_device(dev_get_drvdata(&cdev->dev)));
672 * Allocate a new tape ccw request
674 struct tape_request *
675 tape_alloc_request(int cplength, int datasize)
677 struct tape_request *request;
679 BUG_ON(datasize > PAGE_SIZE || (cplength*sizeof(struct ccw1)) > PAGE_SIZE);
681 DBF_LH(6, "tape_alloc_request(%d, %d)\n", cplength, datasize);
683 request = kzalloc(sizeof(struct tape_request), GFP_KERNEL);
684 if (request == NULL) {
685 DBF_EXCEPTION(1, "cqra nomem\n");
686 return ERR_PTR(-ENOMEM);
688 /* allocate channel program */
689 if (cplength > 0) {
690 request->cpaddr = kcalloc(cplength, sizeof(struct ccw1),
691 GFP_ATOMIC | GFP_DMA);
692 if (request->cpaddr == NULL) {
693 DBF_EXCEPTION(1, "cqra nomem\n");
694 kfree(request);
695 return ERR_PTR(-ENOMEM);
698 /* alloc small kernel buffer */
699 if (datasize > 0) {
700 request->cpdata = kzalloc(datasize, GFP_KERNEL | GFP_DMA);
701 if (request->cpdata == NULL) {
702 DBF_EXCEPTION(1, "cqra nomem\n");
703 kfree(request->cpaddr);
704 kfree(request);
705 return ERR_PTR(-ENOMEM);
708 DBF_LH(6, "New request %p(%p/%p)\n", request, request->cpaddr,
709 request->cpdata);
711 return request;
715 * Free tape ccw request
717 void
718 tape_free_request (struct tape_request * request)
720 DBF_LH(6, "Free request %p\n", request);
722 if (request->device != NULL) {
723 request->device = tape_put_device(request->device);
725 kfree(request->cpdata);
726 kfree(request->cpaddr);
727 kfree(request);
730 static int
731 __tape_start_io(struct tape_device *device, struct tape_request *request)
733 int rc;
735 #ifdef CONFIG_S390_TAPE_BLOCK
736 if (request->op == TO_BLOCK)
737 device->discipline->check_locate(device, request);
738 #endif
739 rc = ccw_device_start(
740 device->cdev,
741 request->cpaddr,
742 (unsigned long) request,
743 0x00,
744 request->options
746 if (rc == 0) {
747 request->status = TAPE_REQUEST_IN_IO;
748 } else if (rc == -EBUSY) {
749 /* The common I/O subsystem is currently busy. Retry later. */
750 request->status = TAPE_REQUEST_QUEUED;
751 schedule_delayed_work(&device->tape_dnr, 0);
752 rc = 0;
753 } else {
754 /* Start failed. Remove request and indicate failure. */
755 DBF_EVENT(1, "tape: start request failed with RC = %i\n", rc);
757 return rc;
760 static void
761 __tape_start_next_request(struct tape_device *device)
763 struct list_head *l, *n;
764 struct tape_request *request;
765 int rc;
767 DBF_LH(6, "__tape_start_next_request(%p)\n", device);
769 * Try to start each request on request queue until one is
770 * started successful.
772 list_for_each_safe(l, n, &device->req_queue) {
773 request = list_entry(l, struct tape_request, list);
776 * Avoid race condition if bottom-half was triggered more than
777 * once.
779 if (request->status == TAPE_REQUEST_IN_IO)
780 return;
782 * Request has already been stopped. We have to wait until
783 * the request is removed from the queue in the interrupt
784 * handling.
786 if (request->status == TAPE_REQUEST_DONE)
787 return;
790 * We wanted to cancel the request but the common I/O layer
791 * was busy at that time. This can only happen if this
792 * function is called by delayed_next_request.
793 * Otherwise we start the next request on the queue.
795 if (request->status == TAPE_REQUEST_CANCEL) {
796 rc = __tape_cancel_io(device, request);
797 } else {
798 rc = __tape_start_io(device, request);
800 if (rc == 0)
801 return;
803 /* Set ending status. */
804 request->rc = rc;
805 request->status = TAPE_REQUEST_DONE;
807 /* Remove from request queue. */
808 list_del(&request->list);
810 /* Do callback. */
811 if (request->callback != NULL)
812 request->callback(request, request->callback_data);
816 static void
817 tape_delayed_next_request(struct work_struct *work)
819 struct tape_device *device =
820 container_of(work, struct tape_device, tape_dnr.work);
822 DBF_LH(6, "tape_delayed_next_request(%p)\n", device);
823 spin_lock_irq(get_ccwdev_lock(device->cdev));
824 __tape_start_next_request(device);
825 spin_unlock_irq(get_ccwdev_lock(device->cdev));
828 static void tape_long_busy_timeout(unsigned long data)
830 struct tape_request *request;
831 struct tape_device *device;
833 device = (struct tape_device *) data;
834 spin_lock_irq(get_ccwdev_lock(device->cdev));
835 request = list_entry(device->req_queue.next, struct tape_request, list);
836 BUG_ON(request->status != TAPE_REQUEST_LONG_BUSY);
837 DBF_LH(6, "%08x: Long busy timeout.\n", device->cdev_id);
838 __tape_start_next_request(device);
839 device->lb_timeout.data = (unsigned long) tape_put_device(device);
840 spin_unlock_irq(get_ccwdev_lock(device->cdev));
843 static void
844 __tape_end_request(
845 struct tape_device * device,
846 struct tape_request * request,
847 int rc)
849 DBF_LH(6, "__tape_end_request(%p, %p, %i)\n", device, request, rc);
850 if (request) {
851 request->rc = rc;
852 request->status = TAPE_REQUEST_DONE;
854 /* Remove from request queue. */
855 list_del(&request->list);
857 /* Do callback. */
858 if (request->callback != NULL)
859 request->callback(request, request->callback_data);
862 /* Start next request. */
863 if (!list_empty(&device->req_queue))
864 __tape_start_next_request(device);
868 * Write sense data to dbf
870 void
871 tape_dump_sense_dbf(struct tape_device *device, struct tape_request *request,
872 struct irb *irb)
874 unsigned int *sptr;
875 const char* op;
877 if (request != NULL)
878 op = tape_op_verbose[request->op];
879 else
880 op = "---";
881 DBF_EVENT(3, "DSTAT : %02x CSTAT: %02x\n",
882 irb->scsw.cmd.dstat, irb->scsw.cmd.cstat);
883 DBF_EVENT(3, "DEVICE: %08x OP\t: %s\n", device->cdev_id, op);
884 sptr = (unsigned int *) irb->ecw;
885 DBF_EVENT(3, "%08x %08x\n", sptr[0], sptr[1]);
886 DBF_EVENT(3, "%08x %08x\n", sptr[2], sptr[3]);
887 DBF_EVENT(3, "%08x %08x\n", sptr[4], sptr[5]);
888 DBF_EVENT(3, "%08x %08x\n", sptr[6], sptr[7]);
892 * I/O helper function. Adds the request to the request queue
893 * and starts it if the tape is idle. Has to be called with
894 * the device lock held.
896 static int
897 __tape_start_request(struct tape_device *device, struct tape_request *request)
899 int rc;
901 switch (request->op) {
902 case TO_MSEN:
903 case TO_ASSIGN:
904 case TO_UNASSIGN:
905 case TO_READ_ATTMSG:
906 case TO_RDC:
907 if (device->tape_state == TS_INIT)
908 break;
909 if (device->tape_state == TS_UNUSED)
910 break;
911 default:
912 if (device->tape_state == TS_BLKUSE)
913 break;
914 if (device->tape_state != TS_IN_USE)
915 return -ENODEV;
918 /* Increase use count of device for the added request. */
919 request->device = tape_get_device_reference(device);
921 if (list_empty(&device->req_queue)) {
922 /* No other requests are on the queue. Start this one. */
923 rc = __tape_start_io(device, request);
924 if (rc)
925 return rc;
927 DBF_LH(5, "Request %p added for execution.\n", request);
928 list_add(&request->list, &device->req_queue);
929 } else {
930 DBF_LH(5, "Request %p add to queue.\n", request);
931 request->status = TAPE_REQUEST_QUEUED;
932 list_add_tail(&request->list, &device->req_queue);
934 return 0;
938 * Add the request to the request queue, try to start it if the
939 * tape is idle. Return without waiting for end of i/o.
942 tape_do_io_async(struct tape_device *device, struct tape_request *request)
944 int rc;
946 DBF_LH(6, "tape_do_io_async(%p, %p)\n", device, request);
948 spin_lock_irq(get_ccwdev_lock(device->cdev));
949 /* Add request to request queue and try to start it. */
950 rc = __tape_start_request(device, request);
951 spin_unlock_irq(get_ccwdev_lock(device->cdev));
952 return rc;
956 * tape_do_io/__tape_wake_up
957 * Add the request to the request queue, try to start it if the
958 * tape is idle and wait uninterruptible for its completion.
960 static void
961 __tape_wake_up(struct tape_request *request, void *data)
963 request->callback = NULL;
964 wake_up((wait_queue_head_t *) data);
968 tape_do_io(struct tape_device *device, struct tape_request *request)
970 int rc;
972 spin_lock_irq(get_ccwdev_lock(device->cdev));
973 /* Setup callback */
974 request->callback = __tape_wake_up;
975 request->callback_data = &device->wait_queue;
976 /* Add request to request queue and try to start it. */
977 rc = __tape_start_request(device, request);
978 spin_unlock_irq(get_ccwdev_lock(device->cdev));
979 if (rc)
980 return rc;
981 /* Request added to the queue. Wait for its completion. */
982 wait_event(device->wait_queue, (request->callback == NULL));
983 /* Get rc from request */
984 return request->rc;
988 * tape_do_io_interruptible/__tape_wake_up_interruptible
989 * Add the request to the request queue, try to start it if the
990 * tape is idle and wait uninterruptible for its completion.
992 static void
993 __tape_wake_up_interruptible(struct tape_request *request, void *data)
995 request->callback = NULL;
996 wake_up_interruptible((wait_queue_head_t *) data);
1000 tape_do_io_interruptible(struct tape_device *device,
1001 struct tape_request *request)
1003 int rc;
1005 spin_lock_irq(get_ccwdev_lock(device->cdev));
1006 /* Setup callback */
1007 request->callback = __tape_wake_up_interruptible;
1008 request->callback_data = &device->wait_queue;
1009 rc = __tape_start_request(device, request);
1010 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1011 if (rc)
1012 return rc;
1013 /* Request added to the queue. Wait for its completion. */
1014 rc = wait_event_interruptible(device->wait_queue,
1015 (request->callback == NULL));
1016 if (rc != -ERESTARTSYS)
1017 /* Request finished normally. */
1018 return request->rc;
1020 /* Interrupted by a signal. We have to stop the current request. */
1021 spin_lock_irq(get_ccwdev_lock(device->cdev));
1022 rc = __tape_cancel_io(device, request);
1023 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1024 if (rc == 0) {
1025 /* Wait for the interrupt that acknowledges the halt. */
1026 do {
1027 rc = wait_event_interruptible(
1028 device->wait_queue,
1029 (request->callback == NULL)
1031 } while (rc == -ERESTARTSYS);
1033 DBF_EVENT(3, "IO stopped on %08x\n", device->cdev_id);
1034 rc = -ERESTARTSYS;
1036 return rc;
1040 * Stop running ccw.
1043 tape_cancel_io(struct tape_device *device, struct tape_request *request)
1045 int rc;
1047 spin_lock_irq(get_ccwdev_lock(device->cdev));
1048 rc = __tape_cancel_io(device, request);
1049 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1050 return rc;
1054 * Tape interrupt routine, called from the ccw_device layer
1056 static void
1057 __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
1059 struct tape_device *device;
1060 struct tape_request *request;
1061 int rc;
1063 device = dev_get_drvdata(&cdev->dev);
1064 if (device == NULL) {
1065 return;
1067 request = (struct tape_request *) intparm;
1069 DBF_LH(6, "__tape_do_irq(device=%p, request=%p)\n", device, request);
1071 /* On special conditions irb is an error pointer */
1072 if (IS_ERR(irb)) {
1073 /* FIXME: What to do with the request? */
1074 switch (PTR_ERR(irb)) {
1075 case -ETIMEDOUT:
1076 DBF_LH(1, "(%s): Request timed out\n",
1077 dev_name(&cdev->dev));
1078 case -EIO:
1079 __tape_end_request(device, request, -EIO);
1080 break;
1081 default:
1082 DBF_LH(1, "(%s): Unexpected i/o error %li\n",
1083 dev_name(&cdev->dev),
1084 PTR_ERR(irb));
1086 return;
1090 * If the condition code is not zero and the start function bit is
1091 * still set, this is an deferred error and the last start I/O did
1092 * not succeed. At this point the condition that caused the deferred
1093 * error might still apply. So we just schedule the request to be
1094 * started later.
1096 if (irb->scsw.cmd.cc != 0 &&
1097 (irb->scsw.cmd.fctl & SCSW_FCTL_START_FUNC) &&
1098 (request->status == TAPE_REQUEST_IN_IO)) {
1099 DBF_EVENT(3,"(%08x): deferred cc=%i, fctl=%i. restarting\n",
1100 device->cdev_id, irb->scsw.cmd.cc, irb->scsw.cmd.fctl);
1101 request->status = TAPE_REQUEST_QUEUED;
1102 schedule_delayed_work(&device->tape_dnr, HZ);
1103 return;
1106 /* May be an unsolicited irq */
1107 if(request != NULL)
1108 request->rescnt = irb->scsw.cmd.count;
1109 else if ((irb->scsw.cmd.dstat == 0x85 || irb->scsw.cmd.dstat == 0x80) &&
1110 !list_empty(&device->req_queue)) {
1111 /* Not Ready to Ready after long busy ? */
1112 struct tape_request *req;
1113 req = list_entry(device->req_queue.next,
1114 struct tape_request, list);
1115 if (req->status == TAPE_REQUEST_LONG_BUSY) {
1116 DBF_EVENT(3, "(%08x): del timer\n", device->cdev_id);
1117 if (del_timer(&device->lb_timeout)) {
1118 device->lb_timeout.data = (unsigned long)
1119 tape_put_device(device);
1120 __tape_start_next_request(device);
1122 return;
1125 if (irb->scsw.cmd.dstat != 0x0c) {
1126 /* Set the 'ONLINE' flag depending on sense byte 1 */
1127 if(*(((__u8 *) irb->ecw) + 1) & SENSE_DRIVE_ONLINE)
1128 device->tape_generic_status |= GMT_ONLINE(~0);
1129 else
1130 device->tape_generic_status &= ~GMT_ONLINE(~0);
1133 * Any request that does not come back with channel end
1134 * and device end is unusual. Log the sense data.
1136 DBF_EVENT(3,"-- Tape Interrupthandler --\n");
1137 tape_dump_sense_dbf(device, request, irb);
1138 } else {
1139 /* Upon normal completion the device _is_ online */
1140 device->tape_generic_status |= GMT_ONLINE(~0);
1142 if (device->tape_state == TS_NOT_OPER) {
1143 DBF_EVENT(6, "tape:device is not operational\n");
1144 return;
1148 * Request that were canceled still come back with an interrupt.
1149 * To detect these request the state will be set to TAPE_REQUEST_DONE.
1151 if(request != NULL && request->status == TAPE_REQUEST_DONE) {
1152 __tape_end_request(device, request, -EIO);
1153 return;
1156 rc = device->discipline->irq(device, request, irb);
1158 * rc < 0 : request finished unsuccessfully.
1159 * rc == TAPE_IO_SUCCESS: request finished successfully.
1160 * rc == TAPE_IO_PENDING: request is still running. Ignore rc.
1161 * rc == TAPE_IO_RETRY: request finished but needs another go.
1162 * rc == TAPE_IO_STOP: request needs to get terminated.
1164 switch (rc) {
1165 case TAPE_IO_SUCCESS:
1166 /* Upon normal completion the device _is_ online */
1167 device->tape_generic_status |= GMT_ONLINE(~0);
1168 __tape_end_request(device, request, rc);
1169 break;
1170 case TAPE_IO_PENDING:
1171 break;
1172 case TAPE_IO_LONG_BUSY:
1173 device->lb_timeout.data =
1174 (unsigned long)tape_get_device_reference(device);
1175 device->lb_timeout.expires = jiffies +
1176 LONG_BUSY_TIMEOUT * HZ;
1177 DBF_EVENT(3, "(%08x): add timer\n", device->cdev_id);
1178 add_timer(&device->lb_timeout);
1179 request->status = TAPE_REQUEST_LONG_BUSY;
1180 break;
1181 case TAPE_IO_RETRY:
1182 rc = __tape_start_io(device, request);
1183 if (rc)
1184 __tape_end_request(device, request, rc);
1185 break;
1186 case TAPE_IO_STOP:
1187 rc = __tape_cancel_io(device, request);
1188 if (rc)
1189 __tape_end_request(device, request, rc);
1190 break;
1191 default:
1192 if (rc > 0) {
1193 DBF_EVENT(6, "xunknownrc\n");
1194 __tape_end_request(device, request, -EIO);
1195 } else {
1196 __tape_end_request(device, request, rc);
1198 break;
1203 * Tape device open function used by tape_char & tape_block frontends.
1206 tape_open(struct tape_device *device)
1208 int rc;
1210 spin_lock_irq(get_ccwdev_lock(device->cdev));
1211 if (device->tape_state == TS_NOT_OPER) {
1212 DBF_EVENT(6, "TAPE:nodev\n");
1213 rc = -ENODEV;
1214 } else if (device->tape_state == TS_IN_USE) {
1215 DBF_EVENT(6, "TAPE:dbusy\n");
1216 rc = -EBUSY;
1217 } else if (device->tape_state == TS_BLKUSE) {
1218 DBF_EVENT(6, "TAPE:dbusy\n");
1219 rc = -EBUSY;
1220 } else if (device->discipline != NULL &&
1221 !try_module_get(device->discipline->owner)) {
1222 DBF_EVENT(6, "TAPE:nodisc\n");
1223 rc = -ENODEV;
1224 } else {
1225 tape_state_set(device, TS_IN_USE);
1226 rc = 0;
1228 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1229 return rc;
1233 * Tape device release function used by tape_char & tape_block frontends.
1236 tape_release(struct tape_device *device)
1238 spin_lock_irq(get_ccwdev_lock(device->cdev));
1239 if (device->tape_state == TS_IN_USE)
1240 tape_state_set(device, TS_UNUSED);
1241 module_put(device->discipline->owner);
1242 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1243 return 0;
1247 * Execute a magnetic tape command a number of times.
1250 tape_mtop(struct tape_device *device, int mt_op, int mt_count)
1252 tape_mtop_fn fn;
1253 int rc;
1255 DBF_EVENT(6, "TAPE:mtio\n");
1256 DBF_EVENT(6, "TAPE:ioop: %x\n", mt_op);
1257 DBF_EVENT(6, "TAPE:arg: %x\n", mt_count);
1259 if (mt_op < 0 || mt_op >= TAPE_NR_MTOPS)
1260 return -EINVAL;
1261 fn = device->discipline->mtop_array[mt_op];
1262 if (fn == NULL)
1263 return -EINVAL;
1265 /* We assume that the backends can handle count up to 500. */
1266 if (mt_op == MTBSR || mt_op == MTFSR || mt_op == MTFSF ||
1267 mt_op == MTBSF || mt_op == MTFSFM || mt_op == MTBSFM) {
1268 rc = 0;
1269 for (; mt_count > 500; mt_count -= 500)
1270 if ((rc = fn(device, 500)) != 0)
1271 break;
1272 if (rc == 0)
1273 rc = fn(device, mt_count);
1274 } else
1275 rc = fn(device, mt_count);
1276 return rc;
1281 * Tape init function.
1283 static int
1284 tape_init (void)
1286 TAPE_DBF_AREA = debug_register ( "tape", 2, 2, 4*sizeof(long));
1287 debug_register_view(TAPE_DBF_AREA, &debug_sprintf_view);
1288 #ifdef DBF_LIKE_HELL
1289 debug_set_level(TAPE_DBF_AREA, 6);
1290 #endif
1291 DBF_EVENT(3, "tape init\n");
1292 tape_proc_init();
1293 tapechar_init ();
1294 tapeblock_init ();
1295 return 0;
1299 * Tape exit function.
1301 static void
1302 tape_exit(void)
1304 DBF_EVENT(6, "tape exit\n");
1306 /* Get rid of the frontends */
1307 tapechar_exit();
1308 tapeblock_exit();
1309 tape_proc_cleanup();
1310 debug_unregister (TAPE_DBF_AREA);
1313 MODULE_AUTHOR("(C) 2001 IBM Deutschland Entwicklung GmbH by Carsten Otte and "
1314 "Michael Holzheu (cotte@de.ibm.com,holzheu@de.ibm.com)");
1315 MODULE_DESCRIPTION("Linux on zSeries channel attached tape device driver");
1316 MODULE_LICENSE("GPL");
1318 module_init(tape_init);
1319 module_exit(tape_exit);
1321 EXPORT_SYMBOL(tape_generic_remove);
1322 EXPORT_SYMBOL(tape_generic_probe);
1323 EXPORT_SYMBOL(tape_generic_online);
1324 EXPORT_SYMBOL(tape_generic_offline);
1325 EXPORT_SYMBOL(tape_generic_pm_suspend);
1326 EXPORT_SYMBOL(tape_put_device);
1327 EXPORT_SYMBOL(tape_get_device_reference);
1328 EXPORT_SYMBOL(tape_state_verbose);
1329 EXPORT_SYMBOL(tape_op_verbose);
1330 EXPORT_SYMBOL(tape_state_set);
1331 EXPORT_SYMBOL(tape_med_state_set);
1332 EXPORT_SYMBOL(tape_alloc_request);
1333 EXPORT_SYMBOL(tape_free_request);
1334 EXPORT_SYMBOL(tape_dump_sense_dbf);
1335 EXPORT_SYMBOL(tape_do_io);
1336 EXPORT_SYMBOL(tape_do_io_async);
1337 EXPORT_SYMBOL(tape_do_io_interruptible);
1338 EXPORT_SYMBOL(tape_cancel_io);
1339 EXPORT_SYMBOL(tape_mtop);