2 * drivers/s390/cio/chp.c
4 * Copyright IBM Corp. 1999,2007
5 * Author(s): Cornelia Huck (cornelia.huck@de.ibm.com)
6 * Arnd Bergmann (arndb@de.ibm.com)
7 * Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
10 #include <linux/bug.h>
11 #include <linux/workqueue.h>
12 #include <linux/spinlock.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 <asm/chpid.h>
21 #include "../s390mach.h"
25 #include "cio_debug.h"
28 #define to_channelpath(device) container_of(device, struct channel_path, dev)
29 #define CHP_INFO_UPDATE_INTERVAL 1*HZ
37 /* Map for pending configure tasks. */
38 static enum cfg_task_t chp_cfg_task[__MAX_CSSID + 1][__MAX_CHPID + 1];
39 static DEFINE_MUTEX(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46 /* Time after which channel-path status may be outdated.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 /* Workqueue to perform pending configure tasks. */
50 static struct workqueue_struct *chp_wq;
51 static struct work_struct cfg_work;
53 /* Wait queue for configure completion events. */
54 static wait_queue_head_t cfg_wait_queue;
56 /* Return channel_path struct for given chpid. */
57 static inline struct channel_path *chpid_to_chp(struct chp_id chpid)
59 return channel_subsystems[chpid.cssid]->chps[chpid.id];
62 /* Set vary state for given chpid. */
63 static void set_chp_logically_online(struct chp_id chpid, int onoff)
65 chpid_to_chp(chpid)->state = onoff;
68 /* On succes return 0 if channel-path is varied offline, 1 if it is varied
69 * online. Return -ENODEV if channel-path is not registered. */
70 int chp_get_status(struct chp_id chpid)
72 return (chpid_to_chp(chpid) ? chpid_to_chp(chpid)->state : -ENODEV);
76 * chp_get_sch_opm - return opm for subchannel
79 * Calculate and return the operational path mask (opm) based on the chpids
80 * used by the subchannel and the status of the associated channel-paths.
82 u8 chp_get_sch_opm(struct subchannel *sch)
90 for (i = 0; i < 8; i++) {
92 chpid.id = sch->schib.pmcw.chpid[i];
93 if (chp_get_status(chpid) != 0)
98 EXPORT_SYMBOL_GPL(chp_get_sch_opm);
101 * chp_is_registered - check if a channel-path is registered
102 * @chpid: channel-path ID
104 * Return non-zero if a channel-path with the given chpid is registered,
107 int chp_is_registered(struct chp_id chpid)
109 return chpid_to_chp(chpid) != NULL;
113 * Function: s390_vary_chpid
114 * Varies the specified chpid online or offline
116 static int s390_vary_chpid(struct chp_id chpid, int on)
121 sprintf(dbf_text, on?"varyon%x.%02x":"varyoff%x.%02x", chpid.cssid,
123 CIO_TRACE_EVENT(2, dbf_text);
125 status = chp_get_status(chpid);
126 if (!on && !status) {
127 printk(KERN_ERR "cio: chpid %x.%02x is already offline\n",
128 chpid.cssid, chpid.id);
132 set_chp_logically_online(chpid, on);
133 chsc_chp_vary(chpid, on);
138 * Channel measurement related functions
140 static ssize_t chp_measurement_chars_read(struct kobject *kobj,
141 struct bin_attribute *bin_attr,
142 char *buf, loff_t off, size_t count)
144 struct channel_path *chp;
145 struct device *device;
148 device = container_of(kobj, struct device, kobj);
149 chp = to_channelpath(device);
153 size = sizeof(struct cmg_chars);
157 if (off + count > size)
159 memcpy(buf, chp->cmg_chars + off, count);
163 static struct bin_attribute chp_measurement_chars_attr = {
165 .name = "measurement_chars",
168 .size = sizeof(struct cmg_chars),
169 .read = chp_measurement_chars_read,
172 static void chp_measurement_copy_block(struct cmg_entry *buf,
173 struct channel_subsystem *css,
177 struct cmg_entry *entry, reference_buf;
180 if (chpid.id < 128) {
181 area = css->cub_addr1;
184 area = css->cub_addr2;
185 idx = chpid.id - 128;
187 entry = area + (idx * sizeof(struct cmg_entry));
189 memcpy(buf, entry, sizeof(*entry));
190 memcpy(&reference_buf, entry, sizeof(*entry));
191 } while (reference_buf.values[0] != buf->values[0]);
194 static ssize_t chp_measurement_read(struct kobject *kobj,
195 struct bin_attribute *bin_attr,
196 char *buf, loff_t off, size_t count)
198 struct channel_path *chp;
199 struct channel_subsystem *css;
200 struct device *device;
203 device = container_of(kobj, struct device, kobj);
204 chp = to_channelpath(device);
205 css = to_css(chp->dev.parent);
207 size = sizeof(struct cmg_entry);
209 /* Only allow single reads. */
210 if (off || count < size)
212 chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->chpid);
217 static struct bin_attribute chp_measurement_attr = {
219 .name = "measurement",
222 .size = sizeof(struct cmg_entry),
223 .read = chp_measurement_read,
226 void chp_remove_cmg_attr(struct channel_path *chp)
228 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
229 device_remove_bin_file(&chp->dev, &chp_measurement_attr);
232 int chp_add_cmg_attr(struct channel_path *chp)
236 ret = device_create_bin_file(&chp->dev, &chp_measurement_chars_attr);
239 ret = device_create_bin_file(&chp->dev, &chp_measurement_attr);
241 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
246 * Files for the channel path entries.
248 static ssize_t chp_status_show(struct device *dev,
249 struct device_attribute *attr, char *buf)
251 struct channel_path *chp = to_channelpath(dev);
255 return (chp_get_status(chp->chpid) ? sprintf(buf, "online\n") :
256 sprintf(buf, "offline\n"));
259 static ssize_t chp_status_write(struct device *dev,
260 struct device_attribute *attr,
261 const char *buf, size_t count)
263 struct channel_path *cp = to_channelpath(dev);
268 num_args = sscanf(buf, "%5s", cmd);
272 if (!strnicmp(cmd, "on", 2) || !strcmp(cmd, "1"))
273 error = s390_vary_chpid(cp->chpid, 1);
274 else if (!strnicmp(cmd, "off", 3) || !strcmp(cmd, "0"))
275 error = s390_vary_chpid(cp->chpid, 0);
279 return error < 0 ? error : count;
283 static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
285 static ssize_t chp_configure_show(struct device *dev,
286 struct device_attribute *attr, char *buf)
288 struct channel_path *cp;
291 cp = to_channelpath(dev);
292 status = chp_info_get_status(cp->chpid);
296 return snprintf(buf, PAGE_SIZE, "%d\n", status);
299 static int cfg_wait_idle(void);
301 static ssize_t chp_configure_write(struct device *dev,
302 struct device_attribute *attr,
303 const char *buf, size_t count)
305 struct channel_path *cp;
309 if (sscanf(buf, "%d %c", &val, &delim) != 1)
311 if (val != 0 && val != 1)
313 cp = to_channelpath(dev);
314 chp_cfg_schedule(cp->chpid, val);
320 static DEVICE_ATTR(configure, 0644, chp_configure_show, chp_configure_write);
322 static ssize_t chp_type_show(struct device *dev, struct device_attribute *attr,
325 struct channel_path *chp = to_channelpath(dev);
329 return sprintf(buf, "%x\n", chp->desc.desc);
332 static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
334 static ssize_t chp_cmg_show(struct device *dev, struct device_attribute *attr,
337 struct channel_path *chp = to_channelpath(dev);
341 if (chp->cmg == -1) /* channel measurements not available */
342 return sprintf(buf, "unknown\n");
343 return sprintf(buf, "%x\n", chp->cmg);
346 static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL);
348 static ssize_t chp_shared_show(struct device *dev,
349 struct device_attribute *attr, char *buf)
351 struct channel_path *chp = to_channelpath(dev);
355 if (chp->shared == -1) /* channel measurements not available */
356 return sprintf(buf, "unknown\n");
357 return sprintf(buf, "%x\n", chp->shared);
360 static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL);
362 static struct attribute *chp_attrs[] = {
363 &dev_attr_status.attr,
364 &dev_attr_configure.attr,
367 &dev_attr_shared.attr,
371 static struct attribute_group chp_attr_group = {
375 static void chp_release(struct device *dev)
377 struct channel_path *cp;
379 cp = to_channelpath(dev);
384 * chp_new - register a new channel-path
385 * @chpid - channel-path ID
387 * Create and register data structure representing new channel-path. Return
388 * zero on success, non-zero otherwise.
390 int chp_new(struct chp_id chpid)
392 struct channel_path *chp;
395 if (chp_is_registered(chpid))
397 chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL);
401 /* fill in status, etc. */
404 chp->dev.parent = &channel_subsystems[chpid.cssid]->device;
405 chp->dev.release = chp_release;
406 snprintf(chp->dev.bus_id, BUS_ID_SIZE, "chp%x.%02x", chpid.cssid,
409 /* Obtain channel path description and fill it in. */
410 ret = chsc_determine_channel_path_description(chpid, &chp->desc);
413 if ((chp->desc.flags & 0x80) == 0) {
417 /* Get channel-measurement characteristics. */
418 if (css_chsc_characteristics.scmc && css_chsc_characteristics.secm) {
419 ret = chsc_get_channel_measurement_chars(chp);
426 /* make it known to the system */
427 ret = device_register(&chp->dev);
429 CIO_MSG_EVENT(0, "Could not register chp%x.%02x: %d\n",
430 chpid.cssid, chpid.id, ret);
433 ret = sysfs_create_group(&chp->dev.kobj, &chp_attr_group);
435 device_unregister(&chp->dev);
438 mutex_lock(&channel_subsystems[chpid.cssid]->mutex);
439 if (channel_subsystems[chpid.cssid]->cm_enabled) {
440 ret = chp_add_cmg_attr(chp);
442 sysfs_remove_group(&chp->dev.kobj, &chp_attr_group);
443 device_unregister(&chp->dev);
444 mutex_unlock(&channel_subsystems[chpid.cssid]->mutex);
448 channel_subsystems[chpid.cssid]->chps[chpid.id] = chp;
449 mutex_unlock(&channel_subsystems[chpid.cssid]->mutex);
457 * chp_get_chp_desc - return newly allocated channel-path description
458 * @chpid: channel-path ID
460 * On success return a newly allocated copy of the channel-path description
461 * data associated with the given channel-path ID. Return %NULL on error.
463 void *chp_get_chp_desc(struct chp_id chpid)
465 struct channel_path *chp;
466 struct channel_path_desc *desc;
468 chp = chpid_to_chp(chpid);
471 desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL);
474 memcpy(desc, &chp->desc, sizeof(struct channel_path_desc));
479 * chp_process_crw - process channel-path status change
480 * @crw0: channel report-word to handler
481 * @crw1: second channel-report word (always NULL)
482 * @overflow: crw overflow indication
484 * Handle channel-report-words indicating that the status of a channel-path
487 static void chp_process_crw(struct crw *crw0, struct crw *crw1,
493 css_schedule_eval_all();
496 CIO_CRW_EVENT(2, "CRW reports slct=%d, oflw=%d, "
497 "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
498 crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
499 crw0->erc, crw0->rsid);
501 * Check for solicited machine checks. These are
502 * created by reset channel path and need not be
506 CIO_CRW_EVENT(2, "solicited machine check for "
507 "channel path %02X\n", crw0->rsid);
511 chpid.id = crw0->rsid;
513 case CRW_ERC_IPARM: /* Path has come. */
514 if (!chp_is_registered(chpid))
516 chsc_chp_online(chpid);
518 case CRW_ERC_PERRI: /* Path has gone. */
520 chsc_chp_offline(chpid);
523 CIO_CRW_EVENT(2, "Don't know how to handle erc=%x\n",
528 int chp_ssd_get_mask(struct chsc_ssd_info *ssd, struct chp_link *link)
533 for (i = 0; i < 8; i++) {
535 if (!(ssd->path_mask & mask))
537 if (!chp_id_is_equal(&ssd->chpid[i], &link->chpid))
539 if ((ssd->fla_valid_mask & mask) &&
540 ((ssd->fla[i] & link->fla_mask) != link->fla))
546 EXPORT_SYMBOL_GPL(chp_ssd_get_mask);
548 static inline int info_bit_num(struct chp_id id)
550 return id.id + id.cssid * (__MAX_CHPID + 1);
553 /* Force chp_info refresh on next call to info_validate(). */
554 static void info_expire(void)
556 mutex_lock(&info_lock);
557 chp_info_expires = jiffies - 1;
558 mutex_unlock(&info_lock);
561 /* Ensure that chp_info is up-to-date. */
562 static int info_update(void)
566 mutex_lock(&info_lock);
568 if (time_after(jiffies, chp_info_expires)) {
569 /* Data is too old, update. */
570 rc = sclp_chp_read_info(&chp_info);
571 chp_info_expires = jiffies + CHP_INFO_UPDATE_INTERVAL ;
573 mutex_unlock(&info_lock);
579 * chp_info_get_status - retrieve configure status of a channel-path
580 * @chpid: channel-path ID
582 * On success, return 0 for standby, 1 for configured, 2 for reserved,
583 * 3 for not recognized. Return negative error code on error.
585 int chp_info_get_status(struct chp_id chpid)
594 bit = info_bit_num(chpid);
595 mutex_lock(&info_lock);
596 if (!chp_test_bit(chp_info.recognized, bit))
597 rc = CHP_STATUS_NOT_RECOGNIZED;
598 else if (chp_test_bit(chp_info.configured, bit))
599 rc = CHP_STATUS_CONFIGURED;
600 else if (chp_test_bit(chp_info.standby, bit))
601 rc = CHP_STATUS_STANDBY;
603 rc = CHP_STATUS_RESERVED;
604 mutex_unlock(&info_lock);
609 /* Return configure task for chpid. */
610 static enum cfg_task_t cfg_get_task(struct chp_id chpid)
612 return chp_cfg_task[chpid.cssid][chpid.id];
615 /* Set configure task for chpid. */
616 static void cfg_set_task(struct chp_id chpid, enum cfg_task_t cfg)
618 chp_cfg_task[chpid.cssid][chpid.id] = cfg;
621 /* Perform one configure/deconfigure request. Reschedule work function until
623 static void cfg_func(struct work_struct *work)
629 mutex_lock(&cfg_lock);
631 chp_id_for_each(&chpid) {
632 t = cfg_get_task(chpid);
634 cfg_set_task(chpid, cfg_none);
638 mutex_unlock(&cfg_lock);
642 rc = sclp_chp_configure(chpid);
644 CIO_MSG_EVENT(2, "chp: sclp_chp_configure(%x.%02x)="
645 "%d\n", chpid.cssid, chpid.id, rc);
648 chsc_chp_online(chpid);
651 case cfg_deconfigure:
652 rc = sclp_chp_deconfigure(chpid);
654 CIO_MSG_EVENT(2, "chp: sclp_chp_deconfigure(%x.%02x)="
655 "%d\n", chpid.cssid, chpid.id, rc);
658 chsc_chp_offline(chpid);
662 /* Get updated information after last change. */
664 mutex_lock(&cfg_lock);
666 mutex_unlock(&cfg_lock);
667 wake_up_interruptible(&cfg_wait_queue);
670 queue_work(chp_wq, &cfg_work);
674 * chp_cfg_schedule - schedule chpid configuration request
675 * @chpid - channel-path ID
676 * @configure - Non-zero for configure, zero for deconfigure
678 * Schedule a channel-path configuration/deconfiguration request.
680 void chp_cfg_schedule(struct chp_id chpid, int configure)
682 CIO_MSG_EVENT(2, "chp_cfg_sched%x.%02x=%d\n", chpid.cssid, chpid.id,
684 mutex_lock(&cfg_lock);
685 cfg_set_task(chpid, configure ? cfg_configure : cfg_deconfigure);
687 mutex_unlock(&cfg_lock);
688 queue_work(chp_wq, &cfg_work);
692 * chp_cfg_cancel_deconfigure - cancel chpid deconfiguration request
693 * @chpid - channel-path ID
695 * Cancel an active channel-path deconfiguration request if it has not yet
698 void chp_cfg_cancel_deconfigure(struct chp_id chpid)
700 CIO_MSG_EVENT(2, "chp_cfg_cancel:%x.%02x\n", chpid.cssid, chpid.id);
701 mutex_lock(&cfg_lock);
702 if (cfg_get_task(chpid) == cfg_deconfigure)
703 cfg_set_task(chpid, cfg_none);
704 mutex_unlock(&cfg_lock);
707 static int cfg_wait_idle(void)
709 if (wait_event_interruptible(cfg_wait_queue, !cfg_busy))
714 static int __init chp_init(void)
719 ret = s390_register_crw_handler(CRW_RSC_CPATH, chp_process_crw);
722 chp_wq = create_singlethread_workqueue("cio_chp");
724 s390_unregister_crw_handler(CRW_RSC_CPATH);
727 INIT_WORK(&cfg_work, cfg_func);
728 init_waitqueue_head(&cfg_wait_queue);
731 /* Register available channel-paths. */
732 chp_id_for_each(&chpid) {
733 if (chp_info_get_status(chpid) != CHP_STATUS_NOT_RECOGNIZED)
740 subsys_initcall(chp_init);