2 * Copyright IBM Corp. 1999, 2010
3 * Author(s): Cornelia Huck (cornelia.huck@de.ibm.com)
4 * Arnd Bergmann (arndb@de.ibm.com)
5 * Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
9 #include <linux/workqueue.h>
10 #include <linux/spinlock.h>
11 #include <linux/export.h>
12 #include <linux/sched.h>
13 #include <linux/init.h>
14 #include <linux/jiffies.h>
15 #include <linux/wait.h>
16 #include <linux/mutex.h>
17 #include <linux/errno.h>
18 #include <linux/slab.h>
19 #include <asm/chpid.h>
26 #include "cio_debug.h"
29 #define to_channelpath(device) container_of(device, struct channel_path, dev)
30 #define CHP_INFO_UPDATE_INTERVAL 1*HZ
38 /* Map for pending configure tasks. */
39 static enum cfg_task_t chp_cfg_task[__MAX_CSSID + 1][__MAX_CHPID + 1];
40 static DEFINE_SPINLOCK(cfg_lock);
42 /* Map for channel-path status. */
43 static struct sclp_chp_info chp_info;
44 static DEFINE_MUTEX(info_lock);
46 /* Time after which channel-path status may be outdated. */
47 static unsigned long chp_info_expires;
49 static struct work_struct cfg_work;
51 /* Wait queue for configure completion events. */
52 static wait_queue_head_t cfg_wait_queue;
54 /* Set vary state for given chpid. */
55 static void set_chp_logically_online(struct chp_id chpid, int onoff)
57 chpid_to_chp(chpid)->state = onoff;
60 /* On success return 0 if channel-path is varied offline, 1 if it is varied
61 * online. Return -ENODEV if channel-path is not registered. */
62 int chp_get_status(struct chp_id chpid)
64 return (chpid_to_chp(chpid) ? chpid_to_chp(chpid)->state : -ENODEV);
68 * chp_get_sch_opm - return opm for subchannel
71 * Calculate and return the operational path mask (opm) based on the chpids
72 * used by the subchannel and the status of the associated channel-paths.
74 u8 chp_get_sch_opm(struct subchannel *sch)
82 for (i = 0; i < 8; i++) {
84 chpid.id = sch->schib.pmcw.chpid[i];
85 if (chp_get_status(chpid) != 0)
90 EXPORT_SYMBOL_GPL(chp_get_sch_opm);
93 * chp_is_registered - check if a channel-path is registered
94 * @chpid: channel-path ID
96 * Return non-zero if a channel-path with the given chpid is registered,
99 int chp_is_registered(struct chp_id chpid)
101 return chpid_to_chp(chpid) != NULL;
105 * Function: s390_vary_chpid
106 * Varies the specified chpid online or offline
108 static int s390_vary_chpid(struct chp_id chpid, int on)
113 sprintf(dbf_text, on?"varyon%x.%02x":"varyoff%x.%02x", chpid.cssid,
115 CIO_TRACE_EVENT(2, dbf_text);
117 status = chp_get_status(chpid);
121 set_chp_logically_online(chpid, on);
122 chsc_chp_vary(chpid, on);
127 * Channel measurement related functions
129 static ssize_t chp_measurement_chars_read(struct file *filp,
130 struct kobject *kobj,
131 struct bin_attribute *bin_attr,
132 char *buf, loff_t off, size_t count)
134 struct channel_path *chp;
135 struct device *device;
137 device = container_of(kobj, struct device, kobj);
138 chp = to_channelpath(device);
142 return memory_read_from_buffer(buf, count, &off, &chp->cmg_chars,
143 sizeof(chp->cmg_chars));
146 static struct bin_attribute chp_measurement_chars_attr = {
148 .name = "measurement_chars",
151 .size = sizeof(struct cmg_chars),
152 .read = chp_measurement_chars_read,
155 static void chp_measurement_copy_block(struct cmg_entry *buf,
156 struct channel_subsystem *css,
160 struct cmg_entry *entry, reference_buf;
163 if (chpid.id < 128) {
164 area = css->cub_addr1;
167 area = css->cub_addr2;
168 idx = chpid.id - 128;
170 entry = area + (idx * sizeof(struct cmg_entry));
172 memcpy(buf, entry, sizeof(*entry));
173 memcpy(&reference_buf, entry, sizeof(*entry));
174 } while (reference_buf.values[0] != buf->values[0]);
177 static ssize_t chp_measurement_read(struct file *filp, struct kobject *kobj,
178 struct bin_attribute *bin_attr,
179 char *buf, loff_t off, size_t count)
181 struct channel_path *chp;
182 struct channel_subsystem *css;
183 struct device *device;
186 device = container_of(kobj, struct device, kobj);
187 chp = to_channelpath(device);
188 css = to_css(chp->dev.parent);
190 size = sizeof(struct cmg_entry);
192 /* Only allow single reads. */
193 if (off || count < size)
195 chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->chpid);
200 static struct bin_attribute chp_measurement_attr = {
202 .name = "measurement",
205 .size = sizeof(struct cmg_entry),
206 .read = chp_measurement_read,
209 void chp_remove_cmg_attr(struct channel_path *chp)
211 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
212 device_remove_bin_file(&chp->dev, &chp_measurement_attr);
215 int chp_add_cmg_attr(struct channel_path *chp)
219 ret = device_create_bin_file(&chp->dev, &chp_measurement_chars_attr);
222 ret = device_create_bin_file(&chp->dev, &chp_measurement_attr);
224 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
229 * Files for the channel path entries.
231 static ssize_t chp_status_show(struct device *dev,
232 struct device_attribute *attr, char *buf)
234 struct channel_path *chp = to_channelpath(dev);
237 mutex_lock(&chp->lock);
239 mutex_unlock(&chp->lock);
241 return status ? sprintf(buf, "online\n") : sprintf(buf, "offline\n");
244 static ssize_t chp_status_write(struct device *dev,
245 struct device_attribute *attr,
246 const char *buf, size_t count)
248 struct channel_path *cp = to_channelpath(dev);
253 num_args = sscanf(buf, "%5s", cmd);
257 if (!strncasecmp(cmd, "on", 2) || !strcmp(cmd, "1")) {
258 mutex_lock(&cp->lock);
259 error = s390_vary_chpid(cp->chpid, 1);
260 mutex_unlock(&cp->lock);
261 } else if (!strncasecmp(cmd, "off", 3) || !strcmp(cmd, "0")) {
262 mutex_lock(&cp->lock);
263 error = s390_vary_chpid(cp->chpid, 0);
264 mutex_unlock(&cp->lock);
268 return error < 0 ? error : count;
271 static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
273 static ssize_t chp_configure_show(struct device *dev,
274 struct device_attribute *attr, char *buf)
276 struct channel_path *cp;
279 cp = to_channelpath(dev);
280 status = chp_info_get_status(cp->chpid);
284 return snprintf(buf, PAGE_SIZE, "%d\n", status);
287 static int cfg_wait_idle(void);
289 static ssize_t chp_configure_write(struct device *dev,
290 struct device_attribute *attr,
291 const char *buf, size_t count)
293 struct channel_path *cp;
297 if (sscanf(buf, "%d %c", &val, &delim) != 1)
299 if (val != 0 && val != 1)
301 cp = to_channelpath(dev);
302 chp_cfg_schedule(cp->chpid, val);
308 static DEVICE_ATTR(configure, 0644, chp_configure_show, chp_configure_write);
310 static ssize_t chp_type_show(struct device *dev, struct device_attribute *attr,
313 struct channel_path *chp = to_channelpath(dev);
316 mutex_lock(&chp->lock);
317 type = chp->desc.desc;
318 mutex_unlock(&chp->lock);
319 return sprintf(buf, "%x\n", type);
322 static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
324 static ssize_t chp_cmg_show(struct device *dev, struct device_attribute *attr,
327 struct channel_path *chp = to_channelpath(dev);
331 if (chp->cmg == -1) /* channel measurements not available */
332 return sprintf(buf, "unknown\n");
333 return sprintf(buf, "%x\n", chp->cmg);
336 static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL);
338 static ssize_t chp_shared_show(struct device *dev,
339 struct device_attribute *attr, char *buf)
341 struct channel_path *chp = to_channelpath(dev);
345 if (chp->shared == -1) /* channel measurements not available */
346 return sprintf(buf, "unknown\n");
347 return sprintf(buf, "%x\n", chp->shared);
350 static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL);
352 static ssize_t chp_chid_show(struct device *dev, struct device_attribute *attr,
355 struct channel_path *chp = to_channelpath(dev);
358 mutex_lock(&chp->lock);
359 if (chp->desc_fmt1.flags & 0x10)
360 rc = sprintf(buf, "%04x\n", chp->desc_fmt1.chid);
363 mutex_unlock(&chp->lock);
367 static DEVICE_ATTR(chid, 0444, chp_chid_show, NULL);
369 static ssize_t chp_chid_external_show(struct device *dev,
370 struct device_attribute *attr, char *buf)
372 struct channel_path *chp = to_channelpath(dev);
375 mutex_lock(&chp->lock);
376 if (chp->desc_fmt1.flags & 0x10)
377 rc = sprintf(buf, "%x\n", chp->desc_fmt1.flags & 0x8 ? 1 : 0);
380 mutex_unlock(&chp->lock);
384 static DEVICE_ATTR(chid_external, 0444, chp_chid_external_show, NULL);
386 static struct attribute *chp_attrs[] = {
387 &dev_attr_status.attr,
388 &dev_attr_configure.attr,
391 &dev_attr_shared.attr,
393 &dev_attr_chid_external.attr,
396 static struct attribute_group chp_attr_group = {
399 static const struct attribute_group *chp_attr_groups[] = {
404 static void chp_release(struct device *dev)
406 struct channel_path *cp;
408 cp = to_channelpath(dev);
413 * chp_update_desc - update channel-path description
414 * @chp - channel-path
416 * Update the channel-path description of the specified channel-path
417 * including channel measurement related information.
418 * Return zero on success, non-zero otherwise.
420 int chp_update_desc(struct channel_path *chp)
424 rc = chsc_determine_base_channel_path_desc(chp->chpid, &chp->desc);
429 * Fetching the following data is optional. Not all machines or
430 * hypervisors implement the required chsc commands.
432 chsc_determine_fmt1_channel_path_desc(chp->chpid, &chp->desc_fmt1);
433 chsc_get_channel_measurement_chars(chp);
439 * chp_new - register a new channel-path
440 * @chpid - channel-path ID
442 * Create and register data structure representing new channel-path. Return
443 * zero on success, non-zero otherwise.
445 int chp_new(struct chp_id chpid)
447 struct channel_subsystem *css = css_by_id(chpid.cssid);
448 struct channel_path *chp;
451 if (chp_is_registered(chpid))
453 chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL);
457 /* fill in status, etc. */
460 chp->dev.parent = &css->device;
461 chp->dev.groups = chp_attr_groups;
462 chp->dev.release = chp_release;
463 mutex_init(&chp->lock);
465 /* Obtain channel path description and fill it in. */
466 ret = chp_update_desc(chp);
469 if ((chp->desc.flags & 0x80) == 0) {
473 dev_set_name(&chp->dev, "chp%x.%02x", chpid.cssid, chpid.id);
475 /* make it known to the system */
476 ret = device_register(&chp->dev);
478 CIO_MSG_EVENT(0, "Could not register chp%x.%02x: %d\n",
479 chpid.cssid, chpid.id, ret);
480 put_device(&chp->dev);
483 mutex_lock(&css->mutex);
484 if (css->cm_enabled) {
485 ret = chp_add_cmg_attr(chp);
487 device_unregister(&chp->dev);
488 mutex_unlock(&css->mutex);
492 css->chps[chpid.id] = chp;
493 mutex_unlock(&css->mutex);
502 * chp_get_chp_desc - return newly allocated channel-path description
503 * @chpid: channel-path ID
505 * On success return a newly allocated copy of the channel-path description
506 * data associated with the given channel-path ID. Return %NULL on error.
508 struct channel_path_desc *chp_get_chp_desc(struct chp_id chpid)
510 struct channel_path *chp;
511 struct channel_path_desc *desc;
513 chp = chpid_to_chp(chpid);
516 desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL);
520 mutex_lock(&chp->lock);
521 memcpy(desc, &chp->desc, sizeof(struct channel_path_desc));
522 mutex_unlock(&chp->lock);
527 * chp_process_crw - process channel-path status change
528 * @crw0: channel report-word to handler
529 * @crw1: second channel-report word (always NULL)
530 * @overflow: crw overflow indication
532 * Handle channel-report-words indicating that the status of a channel-path
535 static void chp_process_crw(struct crw *crw0, struct crw *crw1,
541 css_schedule_eval_all();
544 CIO_CRW_EVENT(2, "CRW reports slct=%d, oflw=%d, "
545 "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
546 crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
547 crw0->erc, crw0->rsid);
549 * Check for solicited machine checks. These are
550 * created by reset channel path and need not be
554 CIO_CRW_EVENT(2, "solicited machine check for "
555 "channel path %02X\n", crw0->rsid);
559 chpid.id = crw0->rsid;
561 case CRW_ERC_IPARM: /* Path has come. */
562 if (!chp_is_registered(chpid))
564 chsc_chp_online(chpid);
566 case CRW_ERC_PERRI: /* Path has gone. */
568 chsc_chp_offline(chpid);
571 CIO_CRW_EVENT(2, "Don't know how to handle erc=%x\n",
576 int chp_ssd_get_mask(struct chsc_ssd_info *ssd, struct chp_link *link)
581 for (i = 0; i < 8; i++) {
583 if (!(ssd->path_mask & mask))
585 if (!chp_id_is_equal(&ssd->chpid[i], &link->chpid))
587 if ((ssd->fla_valid_mask & mask) &&
588 ((ssd->fla[i] & link->fla_mask) != link->fla))
594 EXPORT_SYMBOL_GPL(chp_ssd_get_mask);
596 static inline int info_bit_num(struct chp_id id)
598 return id.id + id.cssid * (__MAX_CHPID + 1);
601 /* Force chp_info refresh on next call to info_validate(). */
602 static void info_expire(void)
604 mutex_lock(&info_lock);
605 chp_info_expires = jiffies - 1;
606 mutex_unlock(&info_lock);
609 /* Ensure that chp_info is up-to-date. */
610 static int info_update(void)
614 mutex_lock(&info_lock);
616 if (time_after(jiffies, chp_info_expires)) {
617 /* Data is too old, update. */
618 rc = sclp_chp_read_info(&chp_info);
619 chp_info_expires = jiffies + CHP_INFO_UPDATE_INTERVAL ;
621 mutex_unlock(&info_lock);
627 * chp_info_get_status - retrieve configure status of a channel-path
628 * @chpid: channel-path ID
630 * On success, return 0 for standby, 1 for configured, 2 for reserved,
631 * 3 for not recognized. Return negative error code on error.
633 int chp_info_get_status(struct chp_id chpid)
642 bit = info_bit_num(chpid);
643 mutex_lock(&info_lock);
644 if (!chp_test_bit(chp_info.recognized, bit))
645 rc = CHP_STATUS_NOT_RECOGNIZED;
646 else if (chp_test_bit(chp_info.configured, bit))
647 rc = CHP_STATUS_CONFIGURED;
648 else if (chp_test_bit(chp_info.standby, bit))
649 rc = CHP_STATUS_STANDBY;
651 rc = CHP_STATUS_RESERVED;
652 mutex_unlock(&info_lock);
657 /* Return configure task for chpid. */
658 static enum cfg_task_t cfg_get_task(struct chp_id chpid)
660 return chp_cfg_task[chpid.cssid][chpid.id];
663 /* Set configure task for chpid. */
664 static void cfg_set_task(struct chp_id chpid, enum cfg_task_t cfg)
666 chp_cfg_task[chpid.cssid][chpid.id] = cfg;
669 /* Fetch the first configure task. Set chpid accordingly. */
670 static enum cfg_task_t chp_cfg_fetch_task(struct chp_id *chpid)
672 enum cfg_task_t t = cfg_none;
674 chp_id_for_each(chpid) {
675 t = cfg_get_task(*chpid);
683 /* Perform one configure/deconfigure request. Reschedule work function until
685 static void cfg_func(struct work_struct *work)
691 spin_lock(&cfg_lock);
692 t = chp_cfg_fetch_task(&chpid);
693 spin_unlock(&cfg_lock);
697 rc = sclp_chp_configure(chpid);
699 CIO_MSG_EVENT(2, "chp: sclp_chp_configure(%x.%02x)="
700 "%d\n", chpid.cssid, chpid.id, rc);
703 chsc_chp_online(chpid);
706 case cfg_deconfigure:
707 rc = sclp_chp_deconfigure(chpid);
709 CIO_MSG_EVENT(2, "chp: sclp_chp_deconfigure(%x.%02x)="
710 "%d\n", chpid.cssid, chpid.id, rc);
713 chsc_chp_offline(chpid);
717 /* Get updated information after last change. */
719 wake_up_interruptible(&cfg_wait_queue);
722 spin_lock(&cfg_lock);
723 if (t == cfg_get_task(chpid))
724 cfg_set_task(chpid, cfg_none);
725 spin_unlock(&cfg_lock);
726 schedule_work(&cfg_work);
730 * chp_cfg_schedule - schedule chpid configuration request
731 * @chpid - channel-path ID
732 * @configure - Non-zero for configure, zero for deconfigure
734 * Schedule a channel-path configuration/deconfiguration request.
736 void chp_cfg_schedule(struct chp_id chpid, int configure)
738 CIO_MSG_EVENT(2, "chp_cfg_sched%x.%02x=%d\n", chpid.cssid, chpid.id,
740 spin_lock(&cfg_lock);
741 cfg_set_task(chpid, configure ? cfg_configure : cfg_deconfigure);
742 spin_unlock(&cfg_lock);
743 schedule_work(&cfg_work);
747 * chp_cfg_cancel_deconfigure - cancel chpid deconfiguration request
748 * @chpid - channel-path ID
750 * Cancel an active channel-path deconfiguration request if it has not yet
753 void chp_cfg_cancel_deconfigure(struct chp_id chpid)
755 CIO_MSG_EVENT(2, "chp_cfg_cancel:%x.%02x\n", chpid.cssid, chpid.id);
756 spin_lock(&cfg_lock);
757 if (cfg_get_task(chpid) == cfg_deconfigure)
758 cfg_set_task(chpid, cfg_none);
759 spin_unlock(&cfg_lock);
762 static bool cfg_idle(void)
767 spin_lock(&cfg_lock);
768 t = chp_cfg_fetch_task(&chpid);
769 spin_unlock(&cfg_lock);
771 return t == cfg_none;
774 static int cfg_wait_idle(void)
776 if (wait_event_interruptible(cfg_wait_queue, cfg_idle()))
781 static int __init chp_init(void)
786 ret = crw_register_handler(CRW_RSC_CPATH, chp_process_crw);
789 INIT_WORK(&cfg_work, cfg_func);
790 init_waitqueue_head(&cfg_wait_queue);
793 /* Register available channel-paths. */
794 chp_id_for_each(&chpid) {
795 state = chp_info_get_status(chpid);
796 if (state == CHP_STATUS_CONFIGURED ||
797 state == CHP_STATUS_STANDBY)
804 subsys_initcall(chp_init);