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_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47 /* Time after which channel-path status may be outdated.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 /* Set vary state for given chpid. */
58 static void set_chp_logically_online(struct chp_id chpid
, int onoff
)
60 chpid_to_chp(chpid
)->state
= onoff
;
63 /* On success return 0 if channel-path is varied offline, 1 if it is varied
64 * online. Return -ENODEV if channel-path is not registered. */
65 int chp_get_status(struct chp_id chpid
)
67 return (chpid_to_chp(chpid
) ? chpid_to_chp(chpid
)->state
: -ENODEV
);
71 * chp_get_sch_opm - return opm for subchannel
74 * Calculate and return the operational path mask (opm) based on the chpids
75 * used by the subchannel and the status of the associated channel-paths.
77 u8
chp_get_sch_opm(struct subchannel
*sch
)
85 for (i
= 0; i
< 8; i
++) {
87 chpid
.id
= sch
->schib
.pmcw
.chpid
[i
];
88 if (chp_get_status(chpid
) != 0)
93 EXPORT_SYMBOL_GPL(chp_get_sch_opm
);
96 * chp_is_registered - check if a channel-path is registered
97 * @chpid: channel-path ID
99 * Return non-zero if a channel-path with the given chpid is registered,
102 int chp_is_registered(struct chp_id chpid
)
104 return chpid_to_chp(chpid
) != NULL
;
108 * Function: s390_vary_chpid
109 * Varies the specified chpid online or offline
111 static int s390_vary_chpid(struct chp_id chpid
, int on
)
116 sprintf(dbf_text
, on
?"varyon%x.%02x":"varyoff%x.%02x", chpid
.cssid
,
118 CIO_TRACE_EVENT(2, dbf_text
);
120 status
= chp_get_status(chpid
);
124 set_chp_logically_online(chpid
, on
);
125 chsc_chp_vary(chpid
, on
);
130 * Channel measurement related functions
132 static ssize_t
chp_measurement_chars_read(struct file
*filp
,
133 struct kobject
*kobj
,
134 struct bin_attribute
*bin_attr
,
135 char *buf
, loff_t off
, size_t count
)
137 struct channel_path
*chp
;
138 struct device
*device
;
140 device
= container_of(kobj
, struct device
, kobj
);
141 chp
= to_channelpath(device
);
145 return memory_read_from_buffer(buf
, count
, &off
,
146 chp
->cmg_chars
, sizeof(struct cmg_chars
));
149 static struct bin_attribute chp_measurement_chars_attr
= {
151 .name
= "measurement_chars",
154 .size
= sizeof(struct cmg_chars
),
155 .read
= chp_measurement_chars_read
,
158 static void chp_measurement_copy_block(struct cmg_entry
*buf
,
159 struct channel_subsystem
*css
,
163 struct cmg_entry
*entry
, reference_buf
;
166 if (chpid
.id
< 128) {
167 area
= css
->cub_addr1
;
170 area
= css
->cub_addr2
;
171 idx
= chpid
.id
- 128;
173 entry
= area
+ (idx
* sizeof(struct cmg_entry
));
175 memcpy(buf
, entry
, sizeof(*entry
));
176 memcpy(&reference_buf
, entry
, sizeof(*entry
));
177 } while (reference_buf
.values
[0] != buf
->values
[0]);
180 static ssize_t
chp_measurement_read(struct file
*filp
, struct kobject
*kobj
,
181 struct bin_attribute
*bin_attr
,
182 char *buf
, loff_t off
, size_t count
)
184 struct channel_path
*chp
;
185 struct channel_subsystem
*css
;
186 struct device
*device
;
189 device
= container_of(kobj
, struct device
, kobj
);
190 chp
= to_channelpath(device
);
191 css
= to_css(chp
->dev
.parent
);
193 size
= sizeof(struct cmg_entry
);
195 /* Only allow single reads. */
196 if (off
|| count
< size
)
198 chp_measurement_copy_block((struct cmg_entry
*)buf
, css
, chp
->chpid
);
203 static struct bin_attribute chp_measurement_attr
= {
205 .name
= "measurement",
208 .size
= sizeof(struct cmg_entry
),
209 .read
= chp_measurement_read
,
212 void chp_remove_cmg_attr(struct channel_path
*chp
)
214 device_remove_bin_file(&chp
->dev
, &chp_measurement_chars_attr
);
215 device_remove_bin_file(&chp
->dev
, &chp_measurement_attr
);
218 int chp_add_cmg_attr(struct channel_path
*chp
)
222 ret
= device_create_bin_file(&chp
->dev
, &chp_measurement_chars_attr
);
225 ret
= device_create_bin_file(&chp
->dev
, &chp_measurement_attr
);
227 device_remove_bin_file(&chp
->dev
, &chp_measurement_chars_attr
);
232 * Files for the channel path entries.
234 static ssize_t
chp_status_show(struct device
*dev
,
235 struct device_attribute
*attr
, char *buf
)
237 struct channel_path
*chp
= to_channelpath(dev
);
240 mutex_lock(&chp
->lock
);
242 mutex_unlock(&chp
->lock
);
244 return status
? sprintf(buf
, "online\n") : sprintf(buf
, "offline\n");
247 static ssize_t
chp_status_write(struct device
*dev
,
248 struct device_attribute
*attr
,
249 const char *buf
, size_t count
)
251 struct channel_path
*cp
= to_channelpath(dev
);
256 num_args
= sscanf(buf
, "%5s", cmd
);
260 if (!strnicmp(cmd
, "on", 2) || !strcmp(cmd
, "1")) {
261 mutex_lock(&cp
->lock
);
262 error
= s390_vary_chpid(cp
->chpid
, 1);
263 mutex_unlock(&cp
->lock
);
264 } else if (!strnicmp(cmd
, "off", 3) || !strcmp(cmd
, "0")) {
265 mutex_lock(&cp
->lock
);
266 error
= s390_vary_chpid(cp
->chpid
, 0);
267 mutex_unlock(&cp
->lock
);
271 return error
< 0 ? error
: count
;
274 static DEVICE_ATTR(status
, 0644, chp_status_show
, chp_status_write
);
276 static ssize_t
chp_configure_show(struct device
*dev
,
277 struct device_attribute
*attr
, char *buf
)
279 struct channel_path
*cp
;
282 cp
= to_channelpath(dev
);
283 status
= chp_info_get_status(cp
->chpid
);
287 return snprintf(buf
, PAGE_SIZE
, "%d\n", status
);
290 static int cfg_wait_idle(void);
292 static ssize_t
chp_configure_write(struct device
*dev
,
293 struct device_attribute
*attr
,
294 const char *buf
, size_t count
)
296 struct channel_path
*cp
;
300 if (sscanf(buf
, "%d %c", &val
, &delim
) != 1)
302 if (val
!= 0 && val
!= 1)
304 cp
= to_channelpath(dev
);
305 chp_cfg_schedule(cp
->chpid
, val
);
311 static DEVICE_ATTR(configure
, 0644, chp_configure_show
, chp_configure_write
);
313 static ssize_t
chp_type_show(struct device
*dev
, struct device_attribute
*attr
,
316 struct channel_path
*chp
= to_channelpath(dev
);
319 mutex_lock(&chp
->lock
);
320 type
= chp
->desc
.desc
;
321 mutex_unlock(&chp
->lock
);
322 return sprintf(buf
, "%x\n", type
);
325 static DEVICE_ATTR(type
, 0444, chp_type_show
, NULL
);
327 static ssize_t
chp_cmg_show(struct device
*dev
, struct device_attribute
*attr
,
330 struct channel_path
*chp
= to_channelpath(dev
);
334 if (chp
->cmg
== -1) /* channel measurements not available */
335 return sprintf(buf
, "unknown\n");
336 return sprintf(buf
, "%x\n", chp
->cmg
);
339 static DEVICE_ATTR(cmg
, 0444, chp_cmg_show
, NULL
);
341 static ssize_t
chp_shared_show(struct device
*dev
,
342 struct device_attribute
*attr
, char *buf
)
344 struct channel_path
*chp
= to_channelpath(dev
);
348 if (chp
->shared
== -1) /* channel measurements not available */
349 return sprintf(buf
, "unknown\n");
350 return sprintf(buf
, "%x\n", chp
->shared
);
353 static DEVICE_ATTR(shared
, 0444, chp_shared_show
, NULL
);
355 static struct attribute
*chp_attrs
[] = {
356 &dev_attr_status
.attr
,
357 &dev_attr_configure
.attr
,
360 &dev_attr_shared
.attr
,
363 static struct attribute_group chp_attr_group
= {
366 static const struct attribute_group
*chp_attr_groups
[] = {
371 static void chp_release(struct device
*dev
)
373 struct channel_path
*cp
;
375 cp
= to_channelpath(dev
);
380 * chp_new - register a new channel-path
381 * @chpid - channel-path ID
383 * Create and register data structure representing new channel-path. Return
384 * zero on success, non-zero otherwise.
386 int chp_new(struct chp_id chpid
)
388 struct channel_path
*chp
;
391 if (chp_is_registered(chpid
))
393 chp
= kzalloc(sizeof(struct channel_path
), GFP_KERNEL
);
397 /* fill in status, etc. */
400 chp
->dev
.parent
= &channel_subsystems
[chpid
.cssid
]->device
;
401 chp
->dev
.groups
= chp_attr_groups
;
402 chp
->dev
.release
= chp_release
;
403 mutex_init(&chp
->lock
);
405 /* Obtain channel path description and fill it in. */
406 ret
= chsc_determine_base_channel_path_desc(chpid
, &chp
->desc
);
409 if ((chp
->desc
.flags
& 0x80) == 0) {
413 /* Get channel-measurement characteristics. */
414 if (css_chsc_characteristics
.scmc
&& css_chsc_characteristics
.secm
) {
415 ret
= chsc_get_channel_measurement_chars(chp
);
421 dev_set_name(&chp
->dev
, "chp%x.%02x", chpid
.cssid
, chpid
.id
);
423 /* make it known to the system */
424 ret
= device_register(&chp
->dev
);
426 CIO_MSG_EVENT(0, "Could not register chp%x.%02x: %d\n",
427 chpid
.cssid
, chpid
.id
, ret
);
428 put_device(&chp
->dev
);
431 mutex_lock(&channel_subsystems
[chpid
.cssid
]->mutex
);
432 if (channel_subsystems
[chpid
.cssid
]->cm_enabled
) {
433 ret
= chp_add_cmg_attr(chp
);
435 device_unregister(&chp
->dev
);
436 mutex_unlock(&channel_subsystems
[chpid
.cssid
]->mutex
);
440 channel_subsystems
[chpid
.cssid
]->chps
[chpid
.id
] = chp
;
441 mutex_unlock(&channel_subsystems
[chpid
.cssid
]->mutex
);
450 * chp_get_chp_desc - return newly allocated channel-path description
451 * @chpid: channel-path ID
453 * On success return a newly allocated copy of the channel-path description
454 * data associated with the given channel-path ID. Return %NULL on error.
456 void *chp_get_chp_desc(struct chp_id chpid
)
458 struct channel_path
*chp
;
459 struct channel_path_desc
*desc
;
461 chp
= chpid_to_chp(chpid
);
464 desc
= kmalloc(sizeof(struct channel_path_desc
), GFP_KERNEL
);
468 mutex_lock(&chp
->lock
);
469 memcpy(desc
, &chp
->desc
, sizeof(struct channel_path_desc
));
470 mutex_unlock(&chp
->lock
);
475 * chp_process_crw - process channel-path status change
476 * @crw0: channel report-word to handler
477 * @crw1: second channel-report word (always NULL)
478 * @overflow: crw overflow indication
480 * Handle channel-report-words indicating that the status of a channel-path
483 static void chp_process_crw(struct crw
*crw0
, struct crw
*crw1
,
489 css_schedule_eval_all();
492 CIO_CRW_EVENT(2, "CRW reports slct=%d, oflw=%d, "
493 "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
494 crw0
->slct
, crw0
->oflw
, crw0
->chn
, crw0
->rsc
, crw0
->anc
,
495 crw0
->erc
, crw0
->rsid
);
497 * Check for solicited machine checks. These are
498 * created by reset channel path and need not be
502 CIO_CRW_EVENT(2, "solicited machine check for "
503 "channel path %02X\n", crw0
->rsid
);
507 chpid
.id
= crw0
->rsid
;
509 case CRW_ERC_IPARM
: /* Path has come. */
510 if (!chp_is_registered(chpid
))
512 chsc_chp_online(chpid
);
514 case CRW_ERC_PERRI
: /* Path has gone. */
516 chsc_chp_offline(chpid
);
519 CIO_CRW_EVENT(2, "Don't know how to handle erc=%x\n",
524 int chp_ssd_get_mask(struct chsc_ssd_info
*ssd
, struct chp_link
*link
)
529 for (i
= 0; i
< 8; i
++) {
531 if (!(ssd
->path_mask
& mask
))
533 if (!chp_id_is_equal(&ssd
->chpid
[i
], &link
->chpid
))
535 if ((ssd
->fla_valid_mask
& mask
) &&
536 ((ssd
->fla
[i
] & link
->fla_mask
) != link
->fla
))
542 EXPORT_SYMBOL_GPL(chp_ssd_get_mask
);
544 static inline int info_bit_num(struct chp_id id
)
546 return id
.id
+ id
.cssid
* (__MAX_CHPID
+ 1);
549 /* Force chp_info refresh on next call to info_validate(). */
550 static void info_expire(void)
552 mutex_lock(&info_lock
);
553 chp_info_expires
= jiffies
- 1;
554 mutex_unlock(&info_lock
);
557 /* Ensure that chp_info is up-to-date. */
558 static int info_update(void)
562 mutex_lock(&info_lock
);
564 if (time_after(jiffies
, chp_info_expires
)) {
565 /* Data is too old, update. */
566 rc
= sclp_chp_read_info(&chp_info
);
567 chp_info_expires
= jiffies
+ CHP_INFO_UPDATE_INTERVAL
;
569 mutex_unlock(&info_lock
);
575 * chp_info_get_status - retrieve configure status of a channel-path
576 * @chpid: channel-path ID
578 * On success, return 0 for standby, 1 for configured, 2 for reserved,
579 * 3 for not recognized. Return negative error code on error.
581 int chp_info_get_status(struct chp_id chpid
)
590 bit
= info_bit_num(chpid
);
591 mutex_lock(&info_lock
);
592 if (!chp_test_bit(chp_info
.recognized
, bit
))
593 rc
= CHP_STATUS_NOT_RECOGNIZED
;
594 else if (chp_test_bit(chp_info
.configured
, bit
))
595 rc
= CHP_STATUS_CONFIGURED
;
596 else if (chp_test_bit(chp_info
.standby
, bit
))
597 rc
= CHP_STATUS_STANDBY
;
599 rc
= CHP_STATUS_RESERVED
;
600 mutex_unlock(&info_lock
);
605 /* Return configure task for chpid. */
606 static enum cfg_task_t
cfg_get_task(struct chp_id chpid
)
608 return chp_cfg_task
[chpid
.cssid
][chpid
.id
];
611 /* Set configure task for chpid. */
612 static void cfg_set_task(struct chp_id chpid
, enum cfg_task_t cfg
)
614 chp_cfg_task
[chpid
.cssid
][chpid
.id
] = cfg
;
617 /* Perform one configure/deconfigure request. Reschedule work function until
619 static void cfg_func(struct work_struct
*work
)
625 mutex_lock(&cfg_lock
);
627 chp_id_for_each(&chpid
) {
628 t
= cfg_get_task(chpid
);
630 cfg_set_task(chpid
, cfg_none
);
634 mutex_unlock(&cfg_lock
);
638 rc
= sclp_chp_configure(chpid
);
640 CIO_MSG_EVENT(2, "chp: sclp_chp_configure(%x.%02x)="
641 "%d\n", chpid
.cssid
, chpid
.id
, rc
);
644 chsc_chp_online(chpid
);
647 case cfg_deconfigure
:
648 rc
= sclp_chp_deconfigure(chpid
);
650 CIO_MSG_EVENT(2, "chp: sclp_chp_deconfigure(%x.%02x)="
651 "%d\n", chpid
.cssid
, chpid
.id
, rc
);
654 chsc_chp_offline(chpid
);
658 /* Get updated information after last change. */
660 mutex_lock(&cfg_lock
);
662 mutex_unlock(&cfg_lock
);
663 wake_up_interruptible(&cfg_wait_queue
);
666 queue_work(chp_wq
, &cfg_work
);
670 * chp_cfg_schedule - schedule chpid configuration request
671 * @chpid - channel-path ID
672 * @configure - Non-zero for configure, zero for deconfigure
674 * Schedule a channel-path configuration/deconfiguration request.
676 void chp_cfg_schedule(struct chp_id chpid
, int configure
)
678 CIO_MSG_EVENT(2, "chp_cfg_sched%x.%02x=%d\n", chpid
.cssid
, chpid
.id
,
680 mutex_lock(&cfg_lock
);
681 cfg_set_task(chpid
, configure
? cfg_configure
: cfg_deconfigure
);
683 mutex_unlock(&cfg_lock
);
684 queue_work(chp_wq
, &cfg_work
);
688 * chp_cfg_cancel_deconfigure - cancel chpid deconfiguration request
689 * @chpid - channel-path ID
691 * Cancel an active channel-path deconfiguration request if it has not yet
694 void chp_cfg_cancel_deconfigure(struct chp_id chpid
)
696 CIO_MSG_EVENT(2, "chp_cfg_cancel:%x.%02x\n", chpid
.cssid
, chpid
.id
);
697 mutex_lock(&cfg_lock
);
698 if (cfg_get_task(chpid
) == cfg_deconfigure
)
699 cfg_set_task(chpid
, cfg_none
);
700 mutex_unlock(&cfg_lock
);
703 static int cfg_wait_idle(void)
705 if (wait_event_interruptible(cfg_wait_queue
, !cfg_busy
))
710 static int __init
chp_init(void)
715 ret
= crw_register_handler(CRW_RSC_CPATH
, chp_process_crw
);
718 chp_wq
= create_singlethread_workqueue("cio_chp");
720 crw_unregister_handler(CRW_RSC_CPATH
);
723 INIT_WORK(&cfg_work
, cfg_func
);
724 init_waitqueue_head(&cfg_wait_queue
);
727 /* Register available channel-paths. */
728 chp_id_for_each(&chpid
) {
729 if (chp_info_get_status(chpid
) != CHP_STATUS_NOT_RECOGNIZED
)
736 subsys_initcall(chp_init
);