2 * drivers/s390/cio/chp.c
4 * Copyright IBM Corp. 1999,2010
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 <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_MUTEX(cfg_lock);
43 /* Map for channel-path status. */
44 static struct sclp_chp_info chp_info;
45 static DEFINE_MUTEX(info_lock);
47 /* Time after which channel-path status may be outdated. */
48 static unsigned long chp_info_expires;
50 /* Workqueue to perform pending configure tasks. */
51 static struct workqueue_struct *chp_wq;
52 static struct work_struct cfg_work;
54 /* Wait queue for configure completion events. */
55 static wait_queue_head_t cfg_wait_queue;
57 /* Return channel_path struct for given chpid. */
58 static inline struct channel_path *chpid_to_chp(struct chp_id chpid)
60 return channel_subsystems[chpid.cssid]->chps[chpid.id];
63 /* Set vary state for given chpid. */
64 static void set_chp_logically_online(struct chp_id chpid, int onoff)
66 chpid_to_chp(chpid)->state = onoff;
69 /* On success return 0 if channel-path is varied offline, 1 if it is varied
70 * online. Return -ENODEV if channel-path is not registered. */
71 int chp_get_status(struct chp_id chpid)
73 return (chpid_to_chp(chpid) ? chpid_to_chp(chpid)->state : -ENODEV);
77 * chp_get_sch_opm - return opm for subchannel
80 * Calculate and return the operational path mask (opm) based on the chpids
81 * used by the subchannel and the status of the associated channel-paths.
83 u8 chp_get_sch_opm(struct subchannel *sch)
91 for (i = 0; i < 8; i++) {
93 chpid.id = sch->schib.pmcw.chpid[i];
94 if (chp_get_status(chpid) != 0)
99 EXPORT_SYMBOL_GPL(chp_get_sch_opm);
102 * chp_is_registered - check if a channel-path is registered
103 * @chpid: channel-path ID
105 * Return non-zero if a channel-path with the given chpid is registered,
108 int chp_is_registered(struct chp_id chpid)
110 return chpid_to_chp(chpid) != NULL;
114 * Function: s390_vary_chpid
115 * Varies the specified chpid online or offline
117 static int s390_vary_chpid(struct chp_id chpid, int on)
122 sprintf(dbf_text, on?"varyon%x.%02x":"varyoff%x.%02x", chpid.cssid,
124 CIO_TRACE_EVENT(2, dbf_text);
126 status = chp_get_status(chpid);
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 file *filp,
139 struct kobject *kobj,
140 struct bin_attribute *bin_attr,
141 char *buf, loff_t off, size_t count)
143 struct channel_path *chp;
144 struct device *device;
146 device = container_of(kobj, struct device, kobj);
147 chp = to_channelpath(device);
151 return memory_read_from_buffer(buf, count, &off,
152 chp->cmg_chars, sizeof(struct cmg_chars));
155 static struct bin_attribute chp_measurement_chars_attr = {
157 .name = "measurement_chars",
160 .size = sizeof(struct cmg_chars),
161 .read = chp_measurement_chars_read,
164 static void chp_measurement_copy_block(struct cmg_entry *buf,
165 struct channel_subsystem *css,
169 struct cmg_entry *entry, reference_buf;
172 if (chpid.id < 128) {
173 area = css->cub_addr1;
176 area = css->cub_addr2;
177 idx = chpid.id - 128;
179 entry = area + (idx * sizeof(struct cmg_entry));
181 memcpy(buf, entry, sizeof(*entry));
182 memcpy(&reference_buf, entry, sizeof(*entry));
183 } while (reference_buf.values[0] != buf->values[0]);
186 static ssize_t chp_measurement_read(struct file *filp, struct kobject *kobj,
187 struct bin_attribute *bin_attr,
188 char *buf, loff_t off, size_t count)
190 struct channel_path *chp;
191 struct channel_subsystem *css;
192 struct device *device;
195 device = container_of(kobj, struct device, kobj);
196 chp = to_channelpath(device);
197 css = to_css(chp->dev.parent);
199 size = sizeof(struct cmg_entry);
201 /* Only allow single reads. */
202 if (off || count < size)
204 chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->chpid);
209 static struct bin_attribute chp_measurement_attr = {
211 .name = "measurement",
214 .size = sizeof(struct cmg_entry),
215 .read = chp_measurement_read,
218 void chp_remove_cmg_attr(struct channel_path *chp)
220 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
221 device_remove_bin_file(&chp->dev, &chp_measurement_attr);
224 int chp_add_cmg_attr(struct channel_path *chp)
228 ret = device_create_bin_file(&chp->dev, &chp_measurement_chars_attr);
231 ret = device_create_bin_file(&chp->dev, &chp_measurement_attr);
233 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
238 * Files for the channel path entries.
240 static ssize_t chp_status_show(struct device *dev,
241 struct device_attribute *attr, char *buf)
243 struct channel_path *chp = to_channelpath(dev);
246 mutex_lock(&chp->lock);
248 mutex_unlock(&chp->lock);
250 return status ? sprintf(buf, "online\n") : 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 = to_channelpath(dev);
262 num_args = sscanf(buf, "%5s", cmd);
266 if (!strnicmp(cmd, "on", 2) || !strcmp(cmd, "1")) {
267 mutex_lock(&cp->lock);
268 error = s390_vary_chpid(cp->chpid, 1);
269 mutex_unlock(&cp->lock);
270 } else if (!strnicmp(cmd, "off", 3) || !strcmp(cmd, "0")) {
271 mutex_lock(&cp->lock);
272 error = s390_vary_chpid(cp->chpid, 0);
273 mutex_unlock(&cp->lock);
277 return error < 0 ? error : count;
280 static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
282 static ssize_t chp_configure_show(struct device *dev,
283 struct device_attribute *attr, char *buf)
285 struct channel_path *cp;
288 cp = to_channelpath(dev);
289 status = chp_info_get_status(cp->chpid);
293 return snprintf(buf, PAGE_SIZE, "%d\n", status);
296 static int cfg_wait_idle(void);
298 static ssize_t chp_configure_write(struct device *dev,
299 struct device_attribute *attr,
300 const char *buf, size_t count)
302 struct channel_path *cp;
306 if (sscanf(buf, "%d %c", &val, &delim) != 1)
308 if (val != 0 && val != 1)
310 cp = to_channelpath(dev);
311 chp_cfg_schedule(cp->chpid, val);
317 static DEVICE_ATTR(configure, 0644, chp_configure_show, chp_configure_write);
319 static ssize_t chp_type_show(struct device *dev, struct device_attribute *attr,
322 struct channel_path *chp = to_channelpath(dev);
325 mutex_lock(&chp->lock);
326 type = chp->desc.desc;
327 mutex_unlock(&chp->lock);
328 return sprintf(buf, "%x\n", type);
331 static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
333 static ssize_t chp_cmg_show(struct device *dev, struct device_attribute *attr,
336 struct channel_path *chp = to_channelpath(dev);
340 if (chp->cmg == -1) /* channel measurements not available */
341 return sprintf(buf, "unknown\n");
342 return sprintf(buf, "%x\n", chp->cmg);
345 static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL);
347 static ssize_t chp_shared_show(struct device *dev,
348 struct device_attribute *attr, char *buf)
350 struct channel_path *chp = to_channelpath(dev);
354 if (chp->shared == -1) /* channel measurements not available */
355 return sprintf(buf, "unknown\n");
356 return sprintf(buf, "%x\n", chp->shared);
359 static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL);
361 static struct attribute *chp_attrs[] = {
362 &dev_attr_status.attr,
363 &dev_attr_configure.attr,
366 &dev_attr_shared.attr,
370 static struct attribute_group chp_attr_group = {
374 static void chp_release(struct device *dev)
376 struct channel_path *cp;
378 cp = to_channelpath(dev);
383 * chp_new - register a new channel-path
384 * @chpid - channel-path ID
386 * Create and register data structure representing new channel-path. Return
387 * zero on success, non-zero otherwise.
389 int chp_new(struct chp_id chpid)
391 struct channel_path *chp;
394 if (chp_is_registered(chpid))
396 chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL);
400 /* fill in status, etc. */
403 chp->dev.parent = &channel_subsystems[chpid.cssid]->device;
404 chp->dev.release = chp_release;
405 mutex_init(&chp->lock);
407 /* Obtain channel path description and fill it in. */
408 ret = chsc_determine_base_channel_path_desc(chpid, &chp->desc);
411 if ((chp->desc.flags & 0x80) == 0) {
415 /* Get channel-measurement characteristics. */
416 if (css_chsc_characteristics.scmc && css_chsc_characteristics.secm) {
417 ret = chsc_get_channel_measurement_chars(chp);
423 dev_set_name(&chp->dev, "chp%x.%02x", chpid.cssid, chpid.id);
425 /* make it known to the system */
426 ret = device_register(&chp->dev);
428 CIO_MSG_EVENT(0, "Could not register chp%x.%02x: %d\n",
429 chpid.cssid, chpid.id, ret);
430 put_device(&chp->dev);
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);
458 * chp_get_chp_desc - return newly allocated channel-path description
459 * @chpid: channel-path ID
461 * On success return a newly allocated copy of the channel-path description
462 * data associated with the given channel-path ID. Return %NULL on error.
464 void *chp_get_chp_desc(struct chp_id chpid)
466 struct channel_path *chp;
467 struct channel_path_desc *desc;
469 chp = chpid_to_chp(chpid);
472 desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL);
476 mutex_lock(&chp->lock);
477 memcpy(desc, &chp->desc, sizeof(struct channel_path_desc));
478 mutex_unlock(&chp->lock);
483 * chp_process_crw - process channel-path status change
484 * @crw0: channel report-word to handler
485 * @crw1: second channel-report word (always NULL)
486 * @overflow: crw overflow indication
488 * Handle channel-report-words indicating that the status of a channel-path
491 static void chp_process_crw(struct crw *crw0, struct crw *crw1,
497 css_schedule_eval_all();
500 CIO_CRW_EVENT(2, "CRW reports slct=%d, oflw=%d, "
501 "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
502 crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
503 crw0->erc, crw0->rsid);
505 * Check for solicited machine checks. These are
506 * created by reset channel path and need not be
510 CIO_CRW_EVENT(2, "solicited machine check for "
511 "channel path %02X\n", crw0->rsid);
515 chpid.id = crw0->rsid;
517 case CRW_ERC_IPARM: /* Path has come. */
518 if (!chp_is_registered(chpid))
520 chsc_chp_online(chpid);
522 case CRW_ERC_PERRI: /* Path has gone. */
524 chsc_chp_offline(chpid);
527 CIO_CRW_EVENT(2, "Don't know how to handle erc=%x\n",
532 int chp_ssd_get_mask(struct chsc_ssd_info *ssd, struct chp_link *link)
537 for (i = 0; i < 8; i++) {
539 if (!(ssd->path_mask & mask))
541 if (!chp_id_is_equal(&ssd->chpid[i], &link->chpid))
543 if ((ssd->fla_valid_mask & mask) &&
544 ((ssd->fla[i] & link->fla_mask) != link->fla))
550 EXPORT_SYMBOL_GPL(chp_ssd_get_mask);
552 static inline int info_bit_num(struct chp_id id)
554 return id.id + id.cssid * (__MAX_CHPID + 1);
557 /* Force chp_info refresh on next call to info_validate(). */
558 static void info_expire(void)
560 mutex_lock(&info_lock);
561 chp_info_expires = jiffies - 1;
562 mutex_unlock(&info_lock);
565 /* Ensure that chp_info is up-to-date. */
566 static int info_update(void)
570 mutex_lock(&info_lock);
572 if (time_after(jiffies, chp_info_expires)) {
573 /* Data is too old, update. */
574 rc = sclp_chp_read_info(&chp_info);
575 chp_info_expires = jiffies + CHP_INFO_UPDATE_INTERVAL ;
577 mutex_unlock(&info_lock);
583 * chp_info_get_status - retrieve configure status of a channel-path
584 * @chpid: channel-path ID
586 * On success, return 0 for standby, 1 for configured, 2 for reserved,
587 * 3 for not recognized. Return negative error code on error.
589 int chp_info_get_status(struct chp_id chpid)
598 bit = info_bit_num(chpid);
599 mutex_lock(&info_lock);
600 if (!chp_test_bit(chp_info.recognized, bit))
601 rc = CHP_STATUS_NOT_RECOGNIZED;
602 else if (chp_test_bit(chp_info.configured, bit))
603 rc = CHP_STATUS_CONFIGURED;
604 else if (chp_test_bit(chp_info.standby, bit))
605 rc = CHP_STATUS_STANDBY;
607 rc = CHP_STATUS_RESERVED;
608 mutex_unlock(&info_lock);
613 /* Return configure task for chpid. */
614 static enum cfg_task_t cfg_get_task(struct chp_id chpid)
616 return chp_cfg_task[chpid.cssid][chpid.id];
619 /* Set configure task for chpid. */
620 static void cfg_set_task(struct chp_id chpid, enum cfg_task_t cfg)
622 chp_cfg_task[chpid.cssid][chpid.id] = cfg;
625 /* Perform one configure/deconfigure request. Reschedule work function until
627 static void cfg_func(struct work_struct *work)
633 mutex_lock(&cfg_lock);
635 chp_id_for_each(&chpid) {
636 t = cfg_get_task(chpid);
638 cfg_set_task(chpid, cfg_none);
642 mutex_unlock(&cfg_lock);
646 rc = sclp_chp_configure(chpid);
648 CIO_MSG_EVENT(2, "chp: sclp_chp_configure(%x.%02x)="
649 "%d\n", chpid.cssid, chpid.id, rc);
652 chsc_chp_online(chpid);
655 case cfg_deconfigure:
656 rc = sclp_chp_deconfigure(chpid);
658 CIO_MSG_EVENT(2, "chp: sclp_chp_deconfigure(%x.%02x)="
659 "%d\n", chpid.cssid, chpid.id, rc);
662 chsc_chp_offline(chpid);
666 /* Get updated information after last change. */
668 mutex_lock(&cfg_lock);
670 mutex_unlock(&cfg_lock);
671 wake_up_interruptible(&cfg_wait_queue);
674 queue_work(chp_wq, &cfg_work);
678 * chp_cfg_schedule - schedule chpid configuration request
679 * @chpid - channel-path ID
680 * @configure - Non-zero for configure, zero for deconfigure
682 * Schedule a channel-path configuration/deconfiguration request.
684 void chp_cfg_schedule(struct chp_id chpid, int configure)
686 CIO_MSG_EVENT(2, "chp_cfg_sched%x.%02x=%d\n", chpid.cssid, chpid.id,
688 mutex_lock(&cfg_lock);
689 cfg_set_task(chpid, configure ? cfg_configure : cfg_deconfigure);
691 mutex_unlock(&cfg_lock);
692 queue_work(chp_wq, &cfg_work);
696 * chp_cfg_cancel_deconfigure - cancel chpid deconfiguration request
697 * @chpid - channel-path ID
699 * Cancel an active channel-path deconfiguration request if it has not yet
702 void chp_cfg_cancel_deconfigure(struct chp_id chpid)
704 CIO_MSG_EVENT(2, "chp_cfg_cancel:%x.%02x\n", chpid.cssid, chpid.id);
705 mutex_lock(&cfg_lock);
706 if (cfg_get_task(chpid) == cfg_deconfigure)
707 cfg_set_task(chpid, cfg_none);
708 mutex_unlock(&cfg_lock);
711 static int cfg_wait_idle(void)
713 if (wait_event_interruptible(cfg_wait_queue, !cfg_busy))
718 static int __init chp_init(void)
723 ret = crw_register_handler(CRW_RSC_CPATH, chp_process_crw);
726 chp_wq = create_singlethread_workqueue("cio_chp");
728 crw_unregister_handler(CRW_RSC_CPATH);
731 INIT_WORK(&cfg_work, cfg_func);
732 init_waitqueue_head(&cfg_wait_queue);
735 /* Register available channel-paths. */
736 chp_id_for_each(&chpid) {
737 if (chp_info_get_status(chpid) != CHP_STATUS_NOT_RECOGNIZED)
744 subsys_initcall(chp_init);