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 <asm/errno.h>
18 #include <asm/chpid.h>
24 #include "cio_debug.h"
27 #define to_channelpath(device) container_of(device, struct channel_path, dev)
28 #define CHP_INFO_UPDATE_INTERVAL 1*HZ
36 /* Map for pending configure tasks. */
37 static enum cfg_task_t chp_cfg_task[__MAX_CSSID + 1][__MAX_CHPID + 1];
38 static DEFINE_MUTEX(cfg_lock);
41 /* Map for channel-path status. */
42 static struct sclp_chp_info chp_info;
43 static DEFINE_MUTEX(info_lock);
45 /* Time after which channel-path status may be outdated. */
46 static unsigned long chp_info_expires;
48 /* Workqueue to perform pending configure tasks. */
49 static struct workqueue_struct *chp_wq;
50 static struct work_struct cfg_work;
52 /* Wait queue for configure completion events. */
53 static wait_queue_head_t cfg_wait_queue;
55 /* Return channel_path struct for given chpid. */
56 static inline struct channel_path *chpid_to_chp(struct chp_id chpid)
58 return css[chpid.cssid]->chps[chpid.id];
61 /* Set vary state for given chpid. */
62 static void set_chp_logically_online(struct chp_id chpid, int onoff)
64 chpid_to_chp(chpid)->state = onoff;
67 /* On succes return 0 if channel-path is varied offline, 1 if it is varied
68 * online. Return -ENODEV if channel-path is not registered. */
69 int chp_get_status(struct chp_id chpid)
71 return (chpid_to_chp(chpid) ? chpid_to_chp(chpid)->state : -ENODEV);
75 * chp_get_sch_opm - return opm for subchannel
78 * Calculate and return the operational path mask (opm) based on the chpids
79 * used by the subchannel and the status of the associated channel-paths.
81 u8 chp_get_sch_opm(struct subchannel *sch)
89 for (i=0; i < 8; i++) {
91 chpid.id = sch->schib.pmcw.chpid[i];
92 if (chp_get_status(chpid) != 0)
99 * chp_is_registered - check if a channel-path is registered
100 * @chpid: channel-path ID
102 * Return non-zero if a channel-path with the given chpid is registered,
105 int chp_is_registered(struct chp_id chpid)
107 return chpid_to_chp(chpid) != NULL;
111 * Function: s390_vary_chpid
112 * Varies the specified chpid online or offline
114 static int s390_vary_chpid(struct chp_id chpid, int on)
119 sprintf(dbf_text, on?"varyon%x.%02x":"varyoff%x.%02x", chpid.cssid,
121 CIO_TRACE_EVENT( 2, dbf_text);
123 status = chp_get_status(chpid);
124 if (!on && !status) {
125 printk(KERN_ERR "cio: chpid %x.%02x is already offline\n",
126 chpid.cssid, chpid.id);
130 set_chp_logically_online(chpid, on);
131 chsc_chp_vary(chpid, on);
136 * Channel measurement related functions
138 static ssize_t chp_measurement_chars_read(struct kobject *kobj,
139 struct bin_attribute *bin_attr,
140 char *buf, loff_t off, size_t count)
142 struct channel_path *chp;
145 chp = to_channelpath(container_of(kobj, struct device, kobj));
149 size = sizeof(struct cmg_chars);
153 if (off + count > size)
155 memcpy(buf, chp->cmg_chars + off, count);
159 static struct bin_attribute chp_measurement_chars_attr = {
161 .name = "measurement_chars",
164 .size = sizeof(struct cmg_chars),
165 .read = chp_measurement_chars_read,
168 static void chp_measurement_copy_block(struct cmg_entry *buf,
169 struct channel_subsystem *css,
173 struct cmg_entry *entry, reference_buf;
176 if (chpid.id < 128) {
177 area = css->cub_addr1;
180 area = css->cub_addr2;
181 idx = chpid.id - 128;
183 entry = area + (idx * sizeof(struct cmg_entry));
185 memcpy(buf, entry, sizeof(*entry));
186 memcpy(&reference_buf, entry, sizeof(*entry));
187 } while (reference_buf.values[0] != buf->values[0]);
190 static ssize_t chp_measurement_read(struct kobject *kobj,
191 struct bin_attribute *bin_attr,
192 char *buf, loff_t off, size_t count)
194 struct channel_path *chp;
195 struct channel_subsystem *css;
198 chp = to_channelpath(container_of(kobj, struct device, kobj));
199 css = to_css(chp->dev.parent);
201 size = sizeof(struct cmg_entry);
203 /* Only allow single reads. */
204 if (off || count < size)
206 chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->chpid);
211 static struct bin_attribute chp_measurement_attr = {
213 .name = "measurement",
216 .size = sizeof(struct cmg_entry),
217 .read = chp_measurement_read,
220 void chp_remove_cmg_attr(struct channel_path *chp)
222 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
223 device_remove_bin_file(&chp->dev, &chp_measurement_attr);
226 int chp_add_cmg_attr(struct channel_path *chp)
230 ret = device_create_bin_file(&chp->dev, &chp_measurement_chars_attr);
233 ret = device_create_bin_file(&chp->dev, &chp_measurement_attr);
235 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
240 * Files for the channel path entries.
242 static ssize_t chp_status_show(struct device *dev,
243 struct device_attribute *attr, char *buf)
245 struct channel_path *chp = container_of(dev, struct channel_path, dev);
249 return (chp_get_status(chp->chpid) ? sprintf(buf, "online\n") :
250 sprintf(buf, "offline\n"));
253 static ssize_t chp_status_write(struct device *dev,
254 struct device_attribute *attr,
255 const char *buf, size_t count)
257 struct channel_path *cp = container_of(dev, struct channel_path, dev);
262 num_args = sscanf(buf, "%5s", cmd);
266 if (!strnicmp(cmd, "on", 2) || !strcmp(cmd, "1"))
267 error = s390_vary_chpid(cp->chpid, 1);
268 else if (!strnicmp(cmd, "off", 3) || !strcmp(cmd, "0"))
269 error = s390_vary_chpid(cp->chpid, 0);
273 return error < 0 ? error : count;
277 static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
279 static ssize_t chp_configure_show(struct device *dev,
280 struct device_attribute *attr, char *buf)
282 struct channel_path *cp;
285 cp = container_of(dev, struct channel_path, dev);
286 status = chp_info_get_status(cp->chpid);
290 return snprintf(buf, PAGE_SIZE, "%d\n", status);
293 static int cfg_wait_idle(void);
295 static ssize_t chp_configure_write(struct device *dev,
296 struct device_attribute *attr,
297 const char *buf, size_t count)
299 struct channel_path *cp;
303 if (sscanf(buf, "%d %c", &val, &delim) != 1)
305 if (val != 0 && val != 1)
307 cp = container_of(dev, struct channel_path, dev);
308 chp_cfg_schedule(cp->chpid, val);
314 static DEVICE_ATTR(configure, 0644, chp_configure_show, chp_configure_write);
316 static ssize_t chp_type_show(struct device *dev, struct device_attribute *attr,
319 struct channel_path *chp = container_of(dev, struct channel_path, dev);
323 return sprintf(buf, "%x\n", chp->desc.desc);
326 static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
328 static ssize_t chp_cmg_show(struct device *dev, struct device_attribute *attr,
331 struct channel_path *chp = to_channelpath(dev);
335 if (chp->cmg == -1) /* channel measurements not available */
336 return sprintf(buf, "unknown\n");
337 return sprintf(buf, "%x\n", chp->cmg);
340 static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL);
342 static ssize_t chp_shared_show(struct device *dev,
343 struct device_attribute *attr, char *buf)
345 struct channel_path *chp = to_channelpath(dev);
349 if (chp->shared == -1) /* channel measurements not available */
350 return sprintf(buf, "unknown\n");
351 return sprintf(buf, "%x\n", chp->shared);
354 static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL);
356 static struct attribute * chp_attrs[] = {
357 &dev_attr_status.attr,
358 &dev_attr_configure.attr,
361 &dev_attr_shared.attr,
365 static struct attribute_group chp_attr_group = {
369 static void chp_release(struct device *dev)
371 struct channel_path *cp;
373 cp = container_of(dev, struct channel_path, dev);
378 * chp_new - register a new channel-path
379 * @chpid - channel-path ID
381 * Create and register data structure representing new channel-path. Return
382 * zero on success, non-zero otherwise.
384 int chp_new(struct chp_id chpid)
386 struct channel_path *chp;
389 if (chp_is_registered(chpid))
391 chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL);
395 /* fill in status, etc. */
398 chp->dev.parent = &css[chpid.cssid]->device;
399 chp->dev.release = chp_release;
400 snprintf(chp->dev.bus_id, BUS_ID_SIZE, "chp%x.%02x", chpid.cssid,
403 /* Obtain channel path description and fill it in. */
404 ret = chsc_determine_channel_path_description(chpid, &chp->desc);
407 if ((chp->desc.flags & 0x80) == 0) {
411 /* Get channel-measurement characteristics. */
412 if (css_characteristics_avail && css_chsc_characteristics.scmc
413 && css_chsc_characteristics.secm) {
414 ret = chsc_get_channel_measurement_chars(chp);
421 /* make it known to the system */
422 ret = device_register(&chp->dev);
424 CIO_MSG_EVENT(0, "Could not register chp%x.%02x: %d\n",
425 chpid.cssid, chpid.id, ret);
428 ret = sysfs_create_group(&chp->dev.kobj, &chp_attr_group);
430 device_unregister(&chp->dev);
433 mutex_lock(&css[chpid.cssid]->mutex);
434 if (css[chpid.cssid]->cm_enabled) {
435 ret = chp_add_cmg_attr(chp);
437 sysfs_remove_group(&chp->dev.kobj, &chp_attr_group);
438 device_unregister(&chp->dev);
439 mutex_unlock(&css[chpid.cssid]->mutex);
443 css[chpid.cssid]->chps[chpid.id] = chp;
444 mutex_unlock(&css[chpid.cssid]->mutex);
452 * chp_get_chp_desc - return newly allocated channel-path description
453 * @chpid: channel-path ID
455 * On success return a newly allocated copy of the channel-path description
456 * data associated with the given channel-path ID. Return %NULL on error.
458 void *chp_get_chp_desc(struct chp_id chpid)
460 struct channel_path *chp;
461 struct channel_path_desc *desc;
463 chp = chpid_to_chp(chpid);
466 desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL);
469 memcpy(desc, &chp->desc, sizeof(struct channel_path_desc));
474 * chp_process_crw - process channel-path status change
475 * @id: channel-path ID number
476 * @status: non-zero if channel-path has become available, zero otherwise
478 * Handle channel-report-words indicating that the status of a channel-path
481 void chp_process_crw(int id, int status)
488 if (!chp_is_registered(chpid))
490 chsc_chp_online(chpid);
492 chsc_chp_offline(chpid);
495 static inline int info_bit_num(struct chp_id id)
497 return id.id + id.cssid * (__MAX_CHPID + 1);
500 /* Force chp_info refresh on next call to info_validate(). */
501 static void info_expire(void)
503 mutex_lock(&info_lock);
504 chp_info_expires = jiffies - 1;
505 mutex_unlock(&info_lock);
508 /* Ensure that chp_info is up-to-date. */
509 static int info_update(void)
513 mutex_lock(&info_lock);
515 if (time_after(jiffies, chp_info_expires)) {
516 /* Data is too old, update. */
517 rc = sclp_chp_read_info(&chp_info);
518 chp_info_expires = jiffies + CHP_INFO_UPDATE_INTERVAL ;
520 mutex_unlock(&info_lock);
526 * chp_info_get_status - retrieve configure status of a channel-path
527 * @chpid: channel-path ID
529 * On success, return 0 for standby, 1 for configured, 2 for reserved,
530 * 3 for not recognized. Return negative error code on error.
532 int chp_info_get_status(struct chp_id chpid)
541 bit = info_bit_num(chpid);
542 mutex_lock(&info_lock);
543 if (!chp_test_bit(chp_info.recognized, bit))
544 rc = CHP_STATUS_NOT_RECOGNIZED;
545 else if (chp_test_bit(chp_info.configured, bit))
546 rc = CHP_STATUS_CONFIGURED;
547 else if (chp_test_bit(chp_info.standby, bit))
548 rc = CHP_STATUS_STANDBY;
550 rc = CHP_STATUS_RESERVED;
551 mutex_unlock(&info_lock);
556 /* Return configure task for chpid. */
557 static enum cfg_task_t cfg_get_task(struct chp_id chpid)
559 return chp_cfg_task[chpid.cssid][chpid.id];
562 /* Set configure task for chpid. */
563 static void cfg_set_task(struct chp_id chpid, enum cfg_task_t cfg)
565 chp_cfg_task[chpid.cssid][chpid.id] = cfg;
568 /* Perform one configure/deconfigure request. Reschedule work function until
570 static void cfg_func(struct work_struct *work)
575 mutex_lock(&cfg_lock);
577 chp_id_for_each(&chpid) {
578 t = cfg_get_task(chpid);
580 cfg_set_task(chpid, cfg_none);
584 mutex_unlock(&cfg_lock);
588 sclp_chp_configure(chpid);
590 chsc_chp_online(chpid);
592 case cfg_deconfigure:
593 sclp_chp_deconfigure(chpid);
595 chsc_chp_offline(chpid);
598 /* Get updated information after last change. */
600 mutex_lock(&cfg_lock);
602 mutex_unlock(&cfg_lock);
603 wake_up_interruptible(&cfg_wait_queue);
606 queue_work(chp_wq, &cfg_work);
610 * chp_cfg_schedule - schedule chpid configuration request
611 * @chpid - channel-path ID
612 * @configure - Non-zero for configure, zero for deconfigure
614 * Schedule a channel-path configuration/deconfiguration request.
616 void chp_cfg_schedule(struct chp_id chpid, int configure)
618 CIO_MSG_EVENT(2, "chp_cfg_sched%x.%02x=%d\n", chpid.cssid, chpid.id,
620 mutex_lock(&cfg_lock);
621 cfg_set_task(chpid, configure ? cfg_configure : cfg_deconfigure);
623 mutex_unlock(&cfg_lock);
624 queue_work(chp_wq, &cfg_work);
628 * chp_cfg_cancel_deconfigure - cancel chpid deconfiguration request
629 * @chpid - channel-path ID
631 * Cancel an active channel-path deconfiguration request if it has not yet
634 void chp_cfg_cancel_deconfigure(struct chp_id chpid)
636 CIO_MSG_EVENT(2, "chp_cfg_cancel:%x.%02x\n", chpid.cssid, chpid.id);
637 mutex_lock(&cfg_lock);
638 if (cfg_get_task(chpid) == cfg_deconfigure)
639 cfg_set_task(chpid, cfg_none);
640 mutex_unlock(&cfg_lock);
643 static int cfg_wait_idle(void)
645 if (wait_event_interruptible(cfg_wait_queue, !cfg_busy))
650 static int __init chp_init(void)
654 chp_wq = create_singlethread_workqueue("cio_chp");
657 INIT_WORK(&cfg_work, cfg_func);
658 init_waitqueue_head(&cfg_wait_queue);
661 /* Register available channel-paths. */
662 chp_id_for_each(&chpid) {
663 if (chp_info_get_status(chpid) != CHP_STATUS_NOT_RECOGNIZED)
670 subsys_initcall(chp_init);