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1/*
2 * linux/drivers/s390/cio/cmf.c
3 *
4 * Linux on zSeries Channel Measurement Facility support
5 *
6 * Copyright 2000,2006 IBM Corporation
7 *
8 * Authors: Arnd Bergmann <arndb@de.ibm.com>
9 * Cornelia Huck <cornelia.huck@de.ibm.com>
10 *
11 * original idea from Natarajan Krishnaswami <nkrishna@us.ibm.com>
12 *
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2, or (at your option)
16 * any later version.
17 *
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
22 *
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26 */
27
28#define KMSG_COMPONENT "cio"
29#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
30
31#include <linux/bootmem.h>
32#include <linux/device.h>
33#include <linux/init.h>
34#include <linux/list.h>
35#include <linux/module.h>
36#include <linux/moduleparam.h>
37#include <linux/slab.h>
38#include <linux/timex.h> /* get_clock() */
39
40#include <asm/ccwdev.h>
41#include <asm/cio.h>
42#include <asm/cmb.h>
43#include <asm/div64.h>
44
45#include "cio.h"
46#include "css.h"
47#include "device.h"
48#include "ioasm.h"
49#include "chsc.h"
50
51/*
52 * parameter to enable cmf during boot, possible uses are:
53 * "s390cmf" -- enable cmf and allocate 2 MB of ram so measuring can be
54 * used on any subchannel
55 * "s390cmf=<num>" -- enable cmf and allocate enough memory to measure
56 * <num> subchannel, where <num> is an integer
57 * between 1 and 65535, default is 1024
58 */
59#define ARGSTRING "s390cmf"
60
61/* indices for READCMB */
62enum cmb_index {
63 /* basic and exended format: */
64 cmb_ssch_rsch_count,
65 cmb_sample_count,
66 cmb_device_connect_time,
67 cmb_function_pending_time,
68 cmb_device_disconnect_time,
69 cmb_control_unit_queuing_time,
70 cmb_device_active_only_time,
71 /* extended format only: */
72 cmb_device_busy_time,
73 cmb_initial_command_response_time,
74};
75
76/**
77 * enum cmb_format - types of supported measurement block formats
78 *
79 * @CMF_BASIC: traditional channel measurement blocks supported
80 * by all machines that we run on
81 * @CMF_EXTENDED: improved format that was introduced with the z990
82 * machine
83 * @CMF_AUTODETECT: default: use extended format when running on a machine
84 * supporting extended format, otherwise fall back to
85 * basic format
86 */
87enum cmb_format {
88 CMF_BASIC,
89 CMF_EXTENDED,
90 CMF_AUTODETECT = -1,
91};
92
93/*
94 * format - actual format for all measurement blocks
95 *
96 * The format module parameter can be set to a value of 0 (zero)
97 * or 1, indicating basic or extended format as described for
98 * enum cmb_format.
99 */
100static int format = CMF_AUTODETECT;
101module_param(format, bool, 0444);
102
103/**
104 * struct cmb_operations - functions to use depending on cmb_format
105 *
106 * Most of these functions operate on a struct ccw_device. There is only
107 * one instance of struct cmb_operations because the format of the measurement
108 * data is guaranteed to be the same for every ccw_device.
109 *
110 * @alloc: allocate memory for a channel measurement block,
111 * either with the help of a special pool or with kmalloc
112 * @free: free memory allocated with @alloc
113 * @set: enable or disable measurement
114 * @read: read a measurement entry at an index
115 * @readall: read a measurement block in a common format
116 * @reset: clear the data in the associated measurement block and
117 * reset its time stamp
118 * @align: align an allocated block so that the hardware can use it
119 */
120struct cmb_operations {
121 int (*alloc) (struct ccw_device *);
122 void (*free) (struct ccw_device *);
123 int (*set) (struct ccw_device *, u32);
124 u64 (*read) (struct ccw_device *, int);
125 int (*readall)(struct ccw_device *, struct cmbdata *);
126 void (*reset) (struct ccw_device *);
127 void *(*align) (void *);
128/* private: */
129 struct attribute_group *attr_group;
130};
131static struct cmb_operations *cmbops;
132
133struct cmb_data {
134 void *hw_block; /* Pointer to block updated by hardware */
135 void *last_block; /* Last changed block copied from hardware block */
136 int size; /* Size of hw_block and last_block */
137 unsigned long long last_update; /* when last_block was updated */
138};
139
140/*
141 * Our user interface is designed in terms of nanoseconds,
142 * while the hardware measures total times in its own
143 * unit.
144 */
145static inline u64 time_to_nsec(u32 value)
146{
147 return ((u64)value) * 128000ull;
148}
149
150/*
151 * Users are usually interested in average times,
152 * not accumulated time.
153 * This also helps us with atomicity problems
154 * when reading sinlge values.
155 */
156static inline u64 time_to_avg_nsec(u32 value, u32 count)
157{
158 u64 ret;
159
160 /* no samples yet, avoid division by 0 */
161 if (count == 0)
162 return 0;
163
164 /* value comes in units of 128 µsec */
165 ret = time_to_nsec(value);
166 do_div(ret, count);
167
168 return ret;
169}
170
171/*
172 * Activate or deactivate the channel monitor. When area is NULL,
173 * the monitor is deactivated. The channel monitor needs to
174 * be active in order to measure subchannels, which also need
175 * to be enabled.
176 */
177static inline void cmf_activate(void *area, unsigned int onoff)
178{
179 register void * __gpr2 asm("2");
180 register long __gpr1 asm("1");
181
182 __gpr2 = area;
183 __gpr1 = onoff ? 2 : 0;
184 /* activate channel measurement */
185 asm("schm" : : "d" (__gpr2), "d" (__gpr1) );
186}
187
188static int set_schib(struct ccw_device *cdev, u32 mme, int mbfc,
189 unsigned long address)
190{
191 struct subchannel *sch;
192
193 sch = to_subchannel(cdev->dev.parent);
194
195 sch->config.mme = mme;
196 sch->config.mbfc = mbfc;
197 /* address can be either a block address or a block index */
198 if (mbfc)
199 sch->config.mba = address;
200 else
201 sch->config.mbi = address;
202
203 return cio_commit_config(sch);
204}
205
206struct set_schib_struct {
207 u32 mme;
208 int mbfc;
209 unsigned long address;
210 wait_queue_head_t wait;
211 int ret;
212 struct kref kref;
213};
214
215static void cmf_set_schib_release(struct kref *kref)
216{
217 struct set_schib_struct *set_data;
218
219 set_data = container_of(kref, struct set_schib_struct, kref);
220 kfree(set_data);
221}
222
223#define CMF_PENDING 1
224
225static int set_schib_wait(struct ccw_device *cdev, u32 mme,
226 int mbfc, unsigned long address)
227{
228 struct set_schib_struct *set_data;
229 int ret;
230
231 spin_lock_irq(cdev->ccwlock);
232 if (!cdev->private->cmb) {
233 ret = -ENODEV;
234 goto out;
235 }
236 set_data = kzalloc(sizeof(struct set_schib_struct), GFP_ATOMIC);
237 if (!set_data) {
238 ret = -ENOMEM;
239 goto out;
240 }
241 init_waitqueue_head(&set_data->wait);
242 kref_init(&set_data->kref);
243 set_data->mme = mme;
244 set_data->mbfc = mbfc;
245 set_data->address = address;
246
247 ret = set_schib(cdev, mme, mbfc, address);
248 if (ret != -EBUSY)
249 goto out_put;
250
251 if (cdev->private->state != DEV_STATE_ONLINE) {
252 /* if the device is not online, don't even try again */
253 ret = -EBUSY;
254 goto out_put;
255 }
256
257 cdev->private->state = DEV_STATE_CMFCHANGE;
258 set_data->ret = CMF_PENDING;
259 cdev->private->cmb_wait = set_data;
260
261 spin_unlock_irq(cdev->ccwlock);
262 if (wait_event_interruptible(set_data->wait,
263 set_data->ret != CMF_PENDING)) {
264 spin_lock_irq(cdev->ccwlock);
265 if (set_data->ret == CMF_PENDING) {
266 set_data->ret = -ERESTARTSYS;
267 if (cdev->private->state == DEV_STATE_CMFCHANGE)
268 cdev->private->state = DEV_STATE_ONLINE;
269 }
270 spin_unlock_irq(cdev->ccwlock);
271 }
272 spin_lock_irq(cdev->ccwlock);
273 cdev->private->cmb_wait = NULL;
274 ret = set_data->ret;
275out_put:
276 kref_put(&set_data->kref, cmf_set_schib_release);
277out:
278 spin_unlock_irq(cdev->ccwlock);
279 return ret;
280}
281
282void retry_set_schib(struct ccw_device *cdev)
283{
284 struct set_schib_struct *set_data;
285
286 set_data = cdev->private->cmb_wait;
287 if (!set_data) {
288 WARN_ON(1);
289 return;
290 }
291 kref_get(&set_data->kref);
292 set_data->ret = set_schib(cdev, set_data->mme, set_data->mbfc,
293 set_data->address);
294 wake_up(&set_data->wait);
295 kref_put(&set_data->kref, cmf_set_schib_release);
296}
297
298static int cmf_copy_block(struct ccw_device *cdev)
299{
300 struct subchannel *sch;
301 void *reference_buf;
302 void *hw_block;
303 struct cmb_data *cmb_data;
304
305 sch = to_subchannel(cdev->dev.parent);
306
307 if (cio_update_schib(sch))
308 return -ENODEV;
309
310 if (scsw_fctl(&sch->schib.scsw) & SCSW_FCTL_START_FUNC) {
311 /* Don't copy if a start function is in progress. */
312 if ((!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_SUSPENDED)) &&
313 (scsw_actl(&sch->schib.scsw) &
314 (SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT)) &&
315 (!(scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_SEC_STATUS)))
316 return -EBUSY;
317 }
318 cmb_data = cdev->private->cmb;
319 hw_block = cmbops->align(cmb_data->hw_block);
320 if (!memcmp(cmb_data->last_block, hw_block, cmb_data->size))
321 /* No need to copy. */
322 return 0;
323 reference_buf = kzalloc(cmb_data->size, GFP_ATOMIC);
324 if (!reference_buf)
325 return -ENOMEM;
326 /* Ensure consistency of block copied from hardware. */
327 do {
328 memcpy(cmb_data->last_block, hw_block, cmb_data->size);
329 memcpy(reference_buf, hw_block, cmb_data->size);
330 } while (memcmp(cmb_data->last_block, reference_buf, cmb_data->size));
331 cmb_data->last_update = get_clock();
332 kfree(reference_buf);
333 return 0;
334}
335
336struct copy_block_struct {
337 wait_queue_head_t wait;
338 int ret;
339 struct kref kref;
340};
341
342static void cmf_copy_block_release(struct kref *kref)
343{
344 struct copy_block_struct *copy_block;
345
346 copy_block = container_of(kref, struct copy_block_struct, kref);
347 kfree(copy_block);
348}
349
350static int cmf_cmb_copy_wait(struct ccw_device *cdev)
351{
352 struct copy_block_struct *copy_block;
353 int ret;
354 unsigned long flags;
355
356 spin_lock_irqsave(cdev->ccwlock, flags);
357 if (!cdev->private->cmb) {
358 ret = -ENODEV;
359 goto out;
360 }
361 copy_block = kzalloc(sizeof(struct copy_block_struct), GFP_ATOMIC);
362 if (!copy_block) {
363 ret = -ENOMEM;
364 goto out;
365 }
366 init_waitqueue_head(©_block->wait);
367 kref_init(©_block->kref);
368
369 ret = cmf_copy_block(cdev);
370 if (ret != -EBUSY)
371 goto out_put;
372
373 if (cdev->private->state != DEV_STATE_ONLINE) {
374 ret = -EBUSY;
375 goto out_put;
376 }
377
378 cdev->private->state = DEV_STATE_CMFUPDATE;
379 copy_block->ret = CMF_PENDING;
380 cdev->private->cmb_wait = copy_block;
381
382 spin_unlock_irqrestore(cdev->ccwlock, flags);
383 if (wait_event_interruptible(copy_block->wait,
384 copy_block->ret != CMF_PENDING)) {
385 spin_lock_irqsave(cdev->ccwlock, flags);
386 if (copy_block->ret == CMF_PENDING) {
387 copy_block->ret = -ERESTARTSYS;
388 if (cdev->private->state == DEV_STATE_CMFUPDATE)
389 cdev->private->state = DEV_STATE_ONLINE;
390 }
391 spin_unlock_irqrestore(cdev->ccwlock, flags);
392 }
393 spin_lock_irqsave(cdev->ccwlock, flags);
394 cdev->private->cmb_wait = NULL;
395 ret = copy_block->ret;
396out_put:
397 kref_put(©_block->kref, cmf_copy_block_release);
398out:
399 spin_unlock_irqrestore(cdev->ccwlock, flags);
400 return ret;
401}
402
403void cmf_retry_copy_block(struct ccw_device *cdev)
404{
405 struct copy_block_struct *copy_block;
406
407 copy_block = cdev->private->cmb_wait;
408 if (!copy_block) {
409 WARN_ON(1);
410 return;
411 }
412 kref_get(©_block->kref);
413 copy_block->ret = cmf_copy_block(cdev);
414 wake_up(©_block->wait);
415 kref_put(©_block->kref, cmf_copy_block_release);
416}
417
418static void cmf_generic_reset(struct ccw_device *cdev)
419{
420 struct cmb_data *cmb_data;
421
422 spin_lock_irq(cdev->ccwlock);
423 cmb_data = cdev->private->cmb;
424 if (cmb_data) {
425 memset(cmb_data->last_block, 0, cmb_data->size);
426 /*
427 * Need to reset hw block as well to make the hardware start
428 * from 0 again.
429 */
430 memset(cmbops->align(cmb_data->hw_block), 0, cmb_data->size);
431 cmb_data->last_update = 0;
432 }
433 cdev->private->cmb_start_time = get_clock();
434 spin_unlock_irq(cdev->ccwlock);
435}
436
437/**
438 * struct cmb_area - container for global cmb data
439 *
440 * @mem: pointer to CMBs (only in basic measurement mode)
441 * @list: contains a linked list of all subchannels
442 * @num_channels: number of channels to be measured
443 * @lock: protect concurrent access to @mem and @list
444 */
445struct cmb_area {
446 struct cmb *mem;
447 struct list_head list;
448 int num_channels;
449 spinlock_t lock;
450};
451
452static struct cmb_area cmb_area = {
453 .lock = __SPIN_LOCK_UNLOCKED(cmb_area.lock),
454 .list = LIST_HEAD_INIT(cmb_area.list),
455 .num_channels = 1024,
456};
457
458/* ****** old style CMB handling ********/
459
460/*
461 * Basic channel measurement blocks are allocated in one contiguous
462 * block of memory, which can not be moved as long as any channel
463 * is active. Therefore, a maximum number of subchannels needs to
464 * be defined somewhere. This is a module parameter, defaulting to
465 * a reasonable value of 1024, or 32 kb of memory.
466 * Current kernels don't allow kmalloc with more than 128kb, so the
467 * maximum is 4096.
468 */
469
470module_param_named(maxchannels, cmb_area.num_channels, uint, 0444);
471
472/**
473 * struct cmb - basic channel measurement block
474 * @ssch_rsch_count: number of ssch and rsch
475 * @sample_count: number of samples
476 * @device_connect_time: time of device connect
477 * @function_pending_time: time of function pending
478 * @device_disconnect_time: time of device disconnect
479 * @control_unit_queuing_time: time of control unit queuing
480 * @device_active_only_time: time of device active only
481 * @reserved: unused in basic measurement mode
482 *
483 * The measurement block as used by the hardware. The fields are described
484 * further in z/Architecture Principles of Operation, chapter 17.
485 *
486 * The cmb area made up from these blocks must be a contiguous array and may
487 * not be reallocated or freed.
488 * Only one cmb area can be present in the system.
489 */
490struct cmb {
491 u16 ssch_rsch_count;
492 u16 sample_count;
493 u32 device_connect_time;
494 u32 function_pending_time;
495 u32 device_disconnect_time;
496 u32 control_unit_queuing_time;
497 u32 device_active_only_time;
498 u32 reserved[2];
499};
500
501/*
502 * Insert a single device into the cmb_area list.
503 * Called with cmb_area.lock held from alloc_cmb.
504 */
505static int alloc_cmb_single(struct ccw_device *cdev,
506 struct cmb_data *cmb_data)
507{
508 struct cmb *cmb;
509 struct ccw_device_private *node;
510 int ret;
511
512 spin_lock_irq(cdev->ccwlock);
513 if (!list_empty(&cdev->private->cmb_list)) {
514 ret = -EBUSY;
515 goto out;
516 }
517
518 /*
519 * Find first unused cmb in cmb_area.mem.
520 * This is a little tricky: cmb_area.list
521 * remains sorted by ->cmb->hw_data pointers.
522 */
523 cmb = cmb_area.mem;
524 list_for_each_entry(node, &cmb_area.list, cmb_list) {
525 struct cmb_data *data;
526 data = node->cmb;
527 if ((struct cmb*)data->hw_block > cmb)
528 break;
529 cmb++;
530 }
531 if (cmb - cmb_area.mem >= cmb_area.num_channels) {
532 ret = -ENOMEM;
533 goto out;
534 }
535
536 /* insert new cmb */
537 list_add_tail(&cdev->private->cmb_list, &node->cmb_list);
538 cmb_data->hw_block = cmb;
539 cdev->private->cmb = cmb_data;
540 ret = 0;
541out:
542 spin_unlock_irq(cdev->ccwlock);
543 return ret;
544}
545
546static int alloc_cmb(struct ccw_device *cdev)
547{
548 int ret;
549 struct cmb *mem;
550 ssize_t size;
551 struct cmb_data *cmb_data;
552
553 /* Allocate private cmb_data. */
554 cmb_data = kzalloc(sizeof(struct cmb_data), GFP_KERNEL);
555 if (!cmb_data)
556 return -ENOMEM;
557
558 cmb_data->last_block = kzalloc(sizeof(struct cmb), GFP_KERNEL);
559 if (!cmb_data->last_block) {
560 kfree(cmb_data);
561 return -ENOMEM;
562 }
563 cmb_data->size = sizeof(struct cmb);
564 spin_lock(&cmb_area.lock);
565
566 if (!cmb_area.mem) {
567 /* there is no user yet, so we need a new area */
568 size = sizeof(struct cmb) * cmb_area.num_channels;
569 WARN_ON(!list_empty(&cmb_area.list));
570
571 spin_unlock(&cmb_area.lock);
572 mem = (void*)__get_free_pages(GFP_KERNEL | GFP_DMA,
573 get_order(size));
574 spin_lock(&cmb_area.lock);
575
576 if (cmb_area.mem) {
577 /* ok, another thread was faster */
578 free_pages((unsigned long)mem, get_order(size));
579 } else if (!mem) {
580 /* no luck */
581 ret = -ENOMEM;
582 goto out;
583 } else {
584 /* everything ok */
585 memset(mem, 0, size);
586 cmb_area.mem = mem;
587 cmf_activate(cmb_area.mem, 1);
588 }
589 }
590
591 /* do the actual allocation */
592 ret = alloc_cmb_single(cdev, cmb_data);
593out:
594 spin_unlock(&cmb_area.lock);
595 if (ret) {
596 kfree(cmb_data->last_block);
597 kfree(cmb_data);
598 }
599 return ret;
600}
601
602static void free_cmb(struct ccw_device *cdev)
603{
604 struct ccw_device_private *priv;
605 struct cmb_data *cmb_data;
606
607 spin_lock(&cmb_area.lock);
608 spin_lock_irq(cdev->ccwlock);
609
610 priv = cdev->private;
611
612 if (list_empty(&priv->cmb_list)) {
613 /* already freed */
614 goto out;
615 }
616
617 cmb_data = priv->cmb;
618 priv->cmb = NULL;
619 if (cmb_data)
620 kfree(cmb_data->last_block);
621 kfree(cmb_data);
622 list_del_init(&priv->cmb_list);
623
624 if (list_empty(&cmb_area.list)) {
625 ssize_t size;
626 size = sizeof(struct cmb) * cmb_area.num_channels;
627 cmf_activate(NULL, 0);
628 free_pages((unsigned long)cmb_area.mem, get_order(size));
629 cmb_area.mem = NULL;
630 }
631out:
632 spin_unlock_irq(cdev->ccwlock);
633 spin_unlock(&cmb_area.lock);
634}
635
636static int set_cmb(struct ccw_device *cdev, u32 mme)
637{
638 u16 offset;
639 struct cmb_data *cmb_data;
640 unsigned long flags;
641
642 spin_lock_irqsave(cdev->ccwlock, flags);
643 if (!cdev->private->cmb) {
644 spin_unlock_irqrestore(cdev->ccwlock, flags);
645 return -EINVAL;
646 }
647 cmb_data = cdev->private->cmb;
648 offset = mme ? (struct cmb *)cmb_data->hw_block - cmb_area.mem : 0;
649 spin_unlock_irqrestore(cdev->ccwlock, flags);
650
651 return set_schib_wait(cdev, mme, 0, offset);
652}
653
654static u64 read_cmb(struct ccw_device *cdev, int index)
655{
656 struct cmb *cmb;
657 u32 val;
658 int ret;
659 unsigned long flags;
660
661 ret = cmf_cmb_copy_wait(cdev);
662 if (ret < 0)
663 return 0;
664
665 spin_lock_irqsave(cdev->ccwlock, flags);
666 if (!cdev->private->cmb) {
667 ret = 0;
668 goto out;
669 }
670 cmb = ((struct cmb_data *)cdev->private->cmb)->last_block;
671
672 switch (index) {
673 case cmb_ssch_rsch_count:
674 ret = cmb->ssch_rsch_count;
675 goto out;
676 case cmb_sample_count:
677 ret = cmb->sample_count;
678 goto out;
679 case cmb_device_connect_time:
680 val = cmb->device_connect_time;
681 break;
682 case cmb_function_pending_time:
683 val = cmb->function_pending_time;
684 break;
685 case cmb_device_disconnect_time:
686 val = cmb->device_disconnect_time;
687 break;
688 case cmb_control_unit_queuing_time:
689 val = cmb->control_unit_queuing_time;
690 break;
691 case cmb_device_active_only_time:
692 val = cmb->device_active_only_time;
693 break;
694 default:
695 ret = 0;
696 goto out;
697 }
698 ret = time_to_avg_nsec(val, cmb->sample_count);
699out:
700 spin_unlock_irqrestore(cdev->ccwlock, flags);
701 return ret;
702}
703
704static int readall_cmb(struct ccw_device *cdev, struct cmbdata *data)
705{
706 struct cmb *cmb;
707 struct cmb_data *cmb_data;
708 u64 time;
709 unsigned long flags;
710 int ret;
711
712 ret = cmf_cmb_copy_wait(cdev);
713 if (ret < 0)
714 return ret;
715 spin_lock_irqsave(cdev->ccwlock, flags);
716 cmb_data = cdev->private->cmb;
717 if (!cmb_data) {
718 ret = -ENODEV;
719 goto out;
720 }
721 if (cmb_data->last_update == 0) {
722 ret = -EAGAIN;
723 goto out;
724 }
725 cmb = cmb_data->last_block;
726 time = cmb_data->last_update - cdev->private->cmb_start_time;
727
728 memset(data, 0, sizeof(struct cmbdata));
729
730 /* we only know values before device_busy_time */
731 data->size = offsetof(struct cmbdata, device_busy_time);
732
733 /* convert to nanoseconds */
734 data->elapsed_time = (time * 1000) >> 12;
735
736 /* copy data to new structure */
737 data->ssch_rsch_count = cmb->ssch_rsch_count;
738 data->sample_count = cmb->sample_count;
739
740 /* time fields are converted to nanoseconds while copying */
741 data->device_connect_time = time_to_nsec(cmb->device_connect_time);
742 data->function_pending_time = time_to_nsec(cmb->function_pending_time);
743 data->device_disconnect_time =
744 time_to_nsec(cmb->device_disconnect_time);
745 data->control_unit_queuing_time
746 = time_to_nsec(cmb->control_unit_queuing_time);
747 data->device_active_only_time
748 = time_to_nsec(cmb->device_active_only_time);
749 ret = 0;
750out:
751 spin_unlock_irqrestore(cdev->ccwlock, flags);
752 return ret;
753}
754
755static void reset_cmb(struct ccw_device *cdev)
756{
757 cmf_generic_reset(cdev);
758}
759
760static void * align_cmb(void *area)
761{
762 return area;
763}
764
765static struct attribute_group cmf_attr_group;
766
767static struct cmb_operations cmbops_basic = {
768 .alloc = alloc_cmb,
769 .free = free_cmb,
770 .set = set_cmb,
771 .read = read_cmb,
772 .readall = readall_cmb,
773 .reset = reset_cmb,
774 .align = align_cmb,
775 .attr_group = &cmf_attr_group,
776};
777
778/* ******** extended cmb handling ********/
779
780/**
781 * struct cmbe - extended channel measurement block
782 * @ssch_rsch_count: number of ssch and rsch
783 * @sample_count: number of samples
784 * @device_connect_time: time of device connect
785 * @function_pending_time: time of function pending
786 * @device_disconnect_time: time of device disconnect
787 * @control_unit_queuing_time: time of control unit queuing
788 * @device_active_only_time: time of device active only
789 * @device_busy_time: time of device busy
790 * @initial_command_response_time: initial command response time
791 * @reserved: unused
792 *
793 * The measurement block as used by the hardware. May be in any 64 bit physical
794 * location.
795 * The fields are described further in z/Architecture Principles of Operation,
796 * third edition, chapter 17.
797 */
798struct cmbe {
799 u32 ssch_rsch_count;
800 u32 sample_count;
801 u32 device_connect_time;
802 u32 function_pending_time;
803 u32 device_disconnect_time;
804 u32 control_unit_queuing_time;
805 u32 device_active_only_time;
806 u32 device_busy_time;
807 u32 initial_command_response_time;
808 u32 reserved[7];
809};
810
811/*
812 * kmalloc only guarantees 8 byte alignment, but we need cmbe
813 * pointers to be naturally aligned. Make sure to allocate
814 * enough space for two cmbes.
815 */
816static inline struct cmbe *cmbe_align(struct cmbe *c)
817{
818 unsigned long addr;
819 addr = ((unsigned long)c + sizeof (struct cmbe) - sizeof(long)) &
820 ~(sizeof (struct cmbe) - sizeof(long));
821 return (struct cmbe*)addr;
822}
823
824static int alloc_cmbe(struct ccw_device *cdev)
825{
826 struct cmbe *cmbe;
827 struct cmb_data *cmb_data;
828 int ret;
829
830 cmbe = kzalloc (sizeof (*cmbe) * 2, GFP_KERNEL);
831 if (!cmbe)
832 return -ENOMEM;
833 cmb_data = kzalloc(sizeof(struct cmb_data), GFP_KERNEL);
834 if (!cmb_data) {
835 ret = -ENOMEM;
836 goto out_free;
837 }
838 cmb_data->last_block = kzalloc(sizeof(struct cmbe), GFP_KERNEL);
839 if (!cmb_data->last_block) {
840 ret = -ENOMEM;
841 goto out_free;
842 }
843 cmb_data->size = sizeof(struct cmbe);
844 spin_lock_irq(cdev->ccwlock);
845 if (cdev->private->cmb) {
846 spin_unlock_irq(cdev->ccwlock);
847 ret = -EBUSY;
848 goto out_free;
849 }
850 cmb_data->hw_block = cmbe;
851 cdev->private->cmb = cmb_data;
852 spin_unlock_irq(cdev->ccwlock);
853
854 /* activate global measurement if this is the first channel */
855 spin_lock(&cmb_area.lock);
856 if (list_empty(&cmb_area.list))
857 cmf_activate(NULL, 1);
858 list_add_tail(&cdev->private->cmb_list, &cmb_area.list);
859 spin_unlock(&cmb_area.lock);
860
861 return 0;
862out_free:
863 if (cmb_data)
864 kfree(cmb_data->last_block);
865 kfree(cmb_data);
866 kfree(cmbe);
867 return ret;
868}
869
870static void free_cmbe(struct ccw_device *cdev)
871{
872 struct cmb_data *cmb_data;
873
874 spin_lock_irq(cdev->ccwlock);
875 cmb_data = cdev->private->cmb;
876 cdev->private->cmb = NULL;
877 if (cmb_data)
878 kfree(cmb_data->last_block);
879 kfree(cmb_data);
880 spin_unlock_irq(cdev->ccwlock);
881
882 /* deactivate global measurement if this is the last channel */
883 spin_lock(&cmb_area.lock);
884 list_del_init(&cdev->private->cmb_list);
885 if (list_empty(&cmb_area.list))
886 cmf_activate(NULL, 0);
887 spin_unlock(&cmb_area.lock);
888}
889
890static int set_cmbe(struct ccw_device *cdev, u32 mme)
891{
892 unsigned long mba;
893 struct cmb_data *cmb_data;
894 unsigned long flags;
895
896 spin_lock_irqsave(cdev->ccwlock, flags);
897 if (!cdev->private->cmb) {
898 spin_unlock_irqrestore(cdev->ccwlock, flags);
899 return -EINVAL;
900 }
901 cmb_data = cdev->private->cmb;
902 mba = mme ? (unsigned long) cmbe_align(cmb_data->hw_block) : 0;
903 spin_unlock_irqrestore(cdev->ccwlock, flags);
904
905 return set_schib_wait(cdev, mme, 1, mba);
906}
907
908
909static u64 read_cmbe(struct ccw_device *cdev, int index)
910{
911 struct cmbe *cmb;
912 struct cmb_data *cmb_data;
913 u32 val;
914 int ret;
915 unsigned long flags;
916
917 ret = cmf_cmb_copy_wait(cdev);
918 if (ret < 0)
919 return 0;
920
921 spin_lock_irqsave(cdev->ccwlock, flags);
922 cmb_data = cdev->private->cmb;
923 if (!cmb_data) {
924 ret = 0;
925 goto out;
926 }
927 cmb = cmb_data->last_block;
928
929 switch (index) {
930 case cmb_ssch_rsch_count:
931 ret = cmb->ssch_rsch_count;
932 goto out;
933 case cmb_sample_count:
934 ret = cmb->sample_count;
935 goto out;
936 case cmb_device_connect_time:
937 val = cmb->device_connect_time;
938 break;
939 case cmb_function_pending_time:
940 val = cmb->function_pending_time;
941 break;
942 case cmb_device_disconnect_time:
943 val = cmb->device_disconnect_time;
944 break;
945 case cmb_control_unit_queuing_time:
946 val = cmb->control_unit_queuing_time;
947 break;
948 case cmb_device_active_only_time:
949 val = cmb->device_active_only_time;
950 break;
951 case cmb_device_busy_time:
952 val = cmb->device_busy_time;
953 break;
954 case cmb_initial_command_response_time:
955 val = cmb->initial_command_response_time;
956 break;
957 default:
958 ret = 0;
959 goto out;
960 }
961 ret = time_to_avg_nsec(val, cmb->sample_count);
962out:
963 spin_unlock_irqrestore(cdev->ccwlock, flags);
964 return ret;
965}
966
967static int readall_cmbe(struct ccw_device *cdev, struct cmbdata *data)
968{
969 struct cmbe *cmb;
970 struct cmb_data *cmb_data;
971 u64 time;
972 unsigned long flags;
973 int ret;
974
975 ret = cmf_cmb_copy_wait(cdev);
976 if (ret < 0)
977 return ret;
978 spin_lock_irqsave(cdev->ccwlock, flags);
979 cmb_data = cdev->private->cmb;
980 if (!cmb_data) {
981 ret = -ENODEV;
982 goto out;
983 }
984 if (cmb_data->last_update == 0) {
985 ret = -EAGAIN;
986 goto out;
987 }
988 time = cmb_data->last_update - cdev->private->cmb_start_time;
989
990 memset (data, 0, sizeof(struct cmbdata));
991
992 /* we only know values before device_busy_time */
993 data->size = offsetof(struct cmbdata, device_busy_time);
994
995 /* conver to nanoseconds */
996 data->elapsed_time = (time * 1000) >> 12;
997
998 cmb = cmb_data->last_block;
999 /* copy data to new structure */
1000 data->ssch_rsch_count = cmb->ssch_rsch_count;
1001 data->sample_count = cmb->sample_count;
1002
1003 /* time fields are converted to nanoseconds while copying */
1004 data->device_connect_time = time_to_nsec(cmb->device_connect_time);
1005 data->function_pending_time = time_to_nsec(cmb->function_pending_time);
1006 data->device_disconnect_time =
1007 time_to_nsec(cmb->device_disconnect_time);
1008 data->control_unit_queuing_time
1009 = time_to_nsec(cmb->control_unit_queuing_time);
1010 data->device_active_only_time
1011 = time_to_nsec(cmb->device_active_only_time);
1012 data->device_busy_time = time_to_nsec(cmb->device_busy_time);
1013 data->initial_command_response_time
1014 = time_to_nsec(cmb->initial_command_response_time);
1015
1016 ret = 0;
1017out:
1018 spin_unlock_irqrestore(cdev->ccwlock, flags);
1019 return ret;
1020}
1021
1022static void reset_cmbe(struct ccw_device *cdev)
1023{
1024 cmf_generic_reset(cdev);
1025}
1026
1027static void * align_cmbe(void *area)
1028{
1029 return cmbe_align(area);
1030}
1031
1032static struct attribute_group cmf_attr_group_ext;
1033
1034static struct cmb_operations cmbops_extended = {
1035 .alloc = alloc_cmbe,
1036 .free = free_cmbe,
1037 .set = set_cmbe,
1038 .read = read_cmbe,
1039 .readall = readall_cmbe,
1040 .reset = reset_cmbe,
1041 .align = align_cmbe,
1042 .attr_group = &cmf_attr_group_ext,
1043};
1044
1045static ssize_t cmb_show_attr(struct device *dev, char *buf, enum cmb_index idx)
1046{
1047 return sprintf(buf, "%lld\n",
1048 (unsigned long long) cmf_read(to_ccwdev(dev), idx));
1049}
1050
1051static ssize_t cmb_show_avg_sample_interval(struct device *dev,
1052 struct device_attribute *attr,
1053 char *buf)
1054{
1055 struct ccw_device *cdev;
1056 long interval;
1057 unsigned long count;
1058 struct cmb_data *cmb_data;
1059
1060 cdev = to_ccwdev(dev);
1061 count = cmf_read(cdev, cmb_sample_count);
1062 spin_lock_irq(cdev->ccwlock);
1063 cmb_data = cdev->private->cmb;
1064 if (count) {
1065 interval = cmb_data->last_update -
1066 cdev->private->cmb_start_time;
1067 interval = (interval * 1000) >> 12;
1068 interval /= count;
1069 } else
1070 interval = -1;
1071 spin_unlock_irq(cdev->ccwlock);
1072 return sprintf(buf, "%ld\n", interval);
1073}
1074
1075static ssize_t cmb_show_avg_utilization(struct device *dev,
1076 struct device_attribute *attr,
1077 char *buf)
1078{
1079 struct cmbdata data;
1080 u64 utilization;
1081 unsigned long t, u;
1082 int ret;
1083
1084 ret = cmf_readall(to_ccwdev(dev), &data);
1085 if (ret == -EAGAIN || ret == -ENODEV)
1086 /* No data (yet/currently) available to use for calculation. */
1087 return sprintf(buf, "n/a\n");
1088 else if (ret)
1089 return ret;
1090
1091 utilization = data.device_connect_time +
1092 data.function_pending_time +
1093 data.device_disconnect_time;
1094
1095 /* shift to avoid long long division */
1096 while (-1ul < (data.elapsed_time | utilization)) {
1097 utilization >>= 8;
1098 data.elapsed_time >>= 8;
1099 }
1100
1101 /* calculate value in 0.1 percent units */
1102 t = (unsigned long) data.elapsed_time / 1000;
1103 u = (unsigned long) utilization / t;
1104
1105 return sprintf(buf, "%02ld.%01ld%%\n", u/ 10, u - (u/ 10) * 10);
1106}
1107
1108#define cmf_attr(name) \
1109static ssize_t show_##name(struct device *dev, \
1110 struct device_attribute *attr, char *buf) \
1111{ return cmb_show_attr((dev), buf, cmb_##name); } \
1112static DEVICE_ATTR(name, 0444, show_##name, NULL);
1113
1114#define cmf_attr_avg(name) \
1115static ssize_t show_avg_##name(struct device *dev, \
1116 struct device_attribute *attr, char *buf) \
1117{ return cmb_show_attr((dev), buf, cmb_##name); } \
1118static DEVICE_ATTR(avg_##name, 0444, show_avg_##name, NULL);
1119
1120cmf_attr(ssch_rsch_count);
1121cmf_attr(sample_count);
1122cmf_attr_avg(device_connect_time);
1123cmf_attr_avg(function_pending_time);
1124cmf_attr_avg(device_disconnect_time);
1125cmf_attr_avg(control_unit_queuing_time);
1126cmf_attr_avg(device_active_only_time);
1127cmf_attr_avg(device_busy_time);
1128cmf_attr_avg(initial_command_response_time);
1129
1130static DEVICE_ATTR(avg_sample_interval, 0444, cmb_show_avg_sample_interval,
1131 NULL);
1132static DEVICE_ATTR(avg_utilization, 0444, cmb_show_avg_utilization, NULL);
1133
1134static struct attribute *cmf_attributes[] = {
1135 &dev_attr_avg_sample_interval.attr,
1136 &dev_attr_avg_utilization.attr,
1137 &dev_attr_ssch_rsch_count.attr,
1138 &dev_attr_sample_count.attr,
1139 &dev_attr_avg_device_connect_time.attr,
1140 &dev_attr_avg_function_pending_time.attr,
1141 &dev_attr_avg_device_disconnect_time.attr,
1142 &dev_attr_avg_control_unit_queuing_time.attr,
1143 &dev_attr_avg_device_active_only_time.attr,
1144 NULL,
1145};
1146
1147static struct attribute_group cmf_attr_group = {
1148 .name = "cmf",
1149 .attrs = cmf_attributes,
1150};
1151
1152static struct attribute *cmf_attributes_ext[] = {
1153 &dev_attr_avg_sample_interval.attr,
1154 &dev_attr_avg_utilization.attr,
1155 &dev_attr_ssch_rsch_count.attr,
1156 &dev_attr_sample_count.attr,
1157 &dev_attr_avg_device_connect_time.attr,
1158 &dev_attr_avg_function_pending_time.attr,
1159 &dev_attr_avg_device_disconnect_time.attr,
1160 &dev_attr_avg_control_unit_queuing_time.attr,
1161 &dev_attr_avg_device_active_only_time.attr,
1162 &dev_attr_avg_device_busy_time.attr,
1163 &dev_attr_avg_initial_command_response_time.attr,
1164 NULL,
1165};
1166
1167static struct attribute_group cmf_attr_group_ext = {
1168 .name = "cmf",
1169 .attrs = cmf_attributes_ext,
1170};
1171
1172static ssize_t cmb_enable_show(struct device *dev,
1173 struct device_attribute *attr,
1174 char *buf)
1175{
1176 return sprintf(buf, "%d\n", to_ccwdev(dev)->private->cmb ? 1 : 0);
1177}
1178
1179static ssize_t cmb_enable_store(struct device *dev,
1180 struct device_attribute *attr, const char *buf,
1181 size_t c)
1182{
1183 struct ccw_device *cdev;
1184 int ret;
1185 unsigned long val;
1186
1187 ret = strict_strtoul(buf, 16, &val);
1188 if (ret)
1189 return ret;
1190
1191 cdev = to_ccwdev(dev);
1192
1193 switch (val) {
1194 case 0:
1195 ret = disable_cmf(cdev);
1196 break;
1197 case 1:
1198 ret = enable_cmf(cdev);
1199 break;
1200 }
1201
1202 return c;
1203}
1204
1205DEVICE_ATTR(cmb_enable, 0644, cmb_enable_show, cmb_enable_store);
1206
1207int ccw_set_cmf(struct ccw_device *cdev, int enable)
1208{
1209 return cmbops->set(cdev, enable ? 2 : 0);
1210}
1211
1212/**
1213 * enable_cmf() - switch on the channel measurement for a specific device
1214 * @cdev: The ccw device to be enabled
1215 *
1216 * Returns %0 for success or a negative error value.
1217 *
1218 * Context:
1219 * non-atomic
1220 */
1221int enable_cmf(struct ccw_device *cdev)
1222{
1223 int ret;
1224
1225 ret = cmbops->alloc(cdev);
1226 cmbops->reset(cdev);
1227 if (ret)
1228 return ret;
1229 ret = cmbops->set(cdev, 2);
1230 if (ret) {
1231 cmbops->free(cdev);
1232 return ret;
1233 }
1234 ret = sysfs_create_group(&cdev->dev.kobj, cmbops->attr_group);
1235 if (!ret)
1236 return 0;
1237 cmbops->set(cdev, 0); //FIXME: this can fail
1238 cmbops->free(cdev);
1239 return ret;
1240}
1241
1242/**
1243 * disable_cmf() - switch off the channel measurement for a specific device
1244 * @cdev: The ccw device to be disabled
1245 *
1246 * Returns %0 for success or a negative error value.
1247 *
1248 * Context:
1249 * non-atomic
1250 */
1251int disable_cmf(struct ccw_device *cdev)
1252{
1253 int ret;
1254
1255 ret = cmbops->set(cdev, 0);
1256 if (ret)
1257 return ret;
1258 cmbops->free(cdev);
1259 sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);
1260 return ret;
1261}
1262
1263/**
1264 * cmf_read() - read one value from the current channel measurement block
1265 * @cdev: the channel to be read
1266 * @index: the index of the value to be read
1267 *
1268 * Returns the value read or %0 if the value cannot be read.
1269 *
1270 * Context:
1271 * any
1272 */
1273u64 cmf_read(struct ccw_device *cdev, int index)
1274{
1275 return cmbops->read(cdev, index);
1276}
1277
1278/**
1279 * cmf_readall() - read the current channel measurement block
1280 * @cdev: the channel to be read
1281 * @data: a pointer to a data block that will be filled
1282 *
1283 * Returns %0 on success, a negative error value otherwise.
1284 *
1285 * Context:
1286 * any
1287 */
1288int cmf_readall(struct ccw_device *cdev, struct cmbdata *data)
1289{
1290 return cmbops->readall(cdev, data);
1291}
1292
1293/* Reenable cmf when a disconnected device becomes available again. */
1294int cmf_reenable(struct ccw_device *cdev)
1295{
1296 cmbops->reset(cdev);
1297 return cmbops->set(cdev, 2);
1298}
1299
1300static int __init init_cmf(void)
1301{
1302 char *format_string;
1303 char *detect_string = "parameter";
1304
1305 /*
1306 * If the user did not give a parameter, see if we are running on a
1307 * machine supporting extended measurement blocks, otherwise fall back
1308 * to basic mode.
1309 */
1310 if (format == CMF_AUTODETECT) {
1311 if (!css_general_characteristics.ext_mb) {
1312 format = CMF_BASIC;
1313 } else {
1314 format = CMF_EXTENDED;
1315 }
1316 detect_string = "autodetected";
1317 } else {
1318 detect_string = "parameter";
1319 }
1320
1321 switch (format) {
1322 case CMF_BASIC:
1323 format_string = "basic";
1324 cmbops = &cmbops_basic;
1325 break;
1326 case CMF_EXTENDED:
1327 format_string = "extended";
1328 cmbops = &cmbops_extended;
1329 break;
1330 default:
1331 return 1;
1332 }
1333 pr_info("Channel measurement facility initialized using format "
1334 "%s (mode %s)\n", format_string, detect_string);
1335 return 0;
1336}
1337
1338module_init(init_cmf);
1339
1340
1341MODULE_AUTHOR("Arnd Bergmann <arndb@de.ibm.com>");
1342MODULE_LICENSE("GPL");
1343MODULE_DESCRIPTION("channel measurement facility base driver\n"
1344 "Copyright 2003 IBM Corporation\n");
1345
1346EXPORT_SYMBOL_GPL(enable_cmf);
1347EXPORT_SYMBOL_GPL(disable_cmf);
1348EXPORT_SYMBOL_GPL(cmf_read);
1349EXPORT_SYMBOL_GPL(cmf_readall);
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Linux on zSeries Channel Measurement Facility support
4 *
5 * Copyright IBM Corp. 2000, 2006
6 *
7 * Authors: Arnd Bergmann <arndb@de.ibm.com>
8 * Cornelia Huck <cornelia.huck@de.ibm.com>
9 *
10 * original idea from Natarajan Krishnaswami <nkrishna@us.ibm.com>
11 */
12
13#define KMSG_COMPONENT "cio"
14#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
15
16#include <linux/memblock.h>
17#include <linux/device.h>
18#include <linux/init.h>
19#include <linux/list.h>
20#include <linux/export.h>
21#include <linux/moduleparam.h>
22#include <linux/slab.h>
23#include <linux/timex.h> /* get_tod_clock() */
24
25#include <asm/ccwdev.h>
26#include <asm/cio.h>
27#include <asm/cmb.h>
28#include <asm/div64.h>
29
30#include "cio.h"
31#include "css.h"
32#include "device.h"
33#include "ioasm.h"
34#include "chsc.h"
35
36/*
37 * parameter to enable cmf during boot, possible uses are:
38 * "s390cmf" -- enable cmf and allocate 2 MB of ram so measuring can be
39 * used on any subchannel
40 * "s390cmf=<num>" -- enable cmf and allocate enough memory to measure
41 * <num> subchannel, where <num> is an integer
42 * between 1 and 65535, default is 1024
43 */
44#define ARGSTRING "s390cmf"
45
46/* indices for READCMB */
47enum cmb_index {
48 avg_utilization = -1,
49 /* basic and exended format: */
50 cmb_ssch_rsch_count = 0,
51 cmb_sample_count,
52 cmb_device_connect_time,
53 cmb_function_pending_time,
54 cmb_device_disconnect_time,
55 cmb_control_unit_queuing_time,
56 cmb_device_active_only_time,
57 /* extended format only: */
58 cmb_device_busy_time,
59 cmb_initial_command_response_time,
60};
61
62/**
63 * enum cmb_format - types of supported measurement block formats
64 *
65 * @CMF_BASIC: traditional channel measurement blocks supported
66 * by all machines that we run on
67 * @CMF_EXTENDED: improved format that was introduced with the z990
68 * machine
69 * @CMF_AUTODETECT: default: use extended format when running on a machine
70 * supporting extended format, otherwise fall back to
71 * basic format
72 */
73enum cmb_format {
74 CMF_BASIC,
75 CMF_EXTENDED,
76 CMF_AUTODETECT = -1,
77};
78
79/*
80 * format - actual format for all measurement blocks
81 *
82 * The format module parameter can be set to a value of 0 (zero)
83 * or 1, indicating basic or extended format as described for
84 * enum cmb_format.
85 */
86static int format = CMF_AUTODETECT;
87module_param(format, bint, 0444);
88
89/**
90 * struct cmb_operations - functions to use depending on cmb_format
91 *
92 * Most of these functions operate on a struct ccw_device. There is only
93 * one instance of struct cmb_operations because the format of the measurement
94 * data is guaranteed to be the same for every ccw_device.
95 *
96 * @alloc: allocate memory for a channel measurement block,
97 * either with the help of a special pool or with kmalloc
98 * @free: free memory allocated with @alloc
99 * @set: enable or disable measurement
100 * @read: read a measurement entry at an index
101 * @readall: read a measurement block in a common format
102 * @reset: clear the data in the associated measurement block and
103 * reset its time stamp
104 */
105struct cmb_operations {
106 int (*alloc) (struct ccw_device *);
107 void (*free) (struct ccw_device *);
108 int (*set) (struct ccw_device *, u32);
109 u64 (*read) (struct ccw_device *, int);
110 int (*readall)(struct ccw_device *, struct cmbdata *);
111 void (*reset) (struct ccw_device *);
112/* private: */
113 struct attribute_group *attr_group;
114};
115static struct cmb_operations *cmbops;
116
117struct cmb_data {
118 void *hw_block; /* Pointer to block updated by hardware */
119 void *last_block; /* Last changed block copied from hardware block */
120 int size; /* Size of hw_block and last_block */
121 unsigned long long last_update; /* when last_block was updated */
122};
123
124/*
125 * Our user interface is designed in terms of nanoseconds,
126 * while the hardware measures total times in its own
127 * unit.
128 */
129static inline u64 time_to_nsec(u32 value)
130{
131 return ((u64)value) * 128000ull;
132}
133
134/*
135 * Users are usually interested in average times,
136 * not accumulated time.
137 * This also helps us with atomicity problems
138 * when reading sinlge values.
139 */
140static inline u64 time_to_avg_nsec(u32 value, u32 count)
141{
142 u64 ret;
143
144 /* no samples yet, avoid division by 0 */
145 if (count == 0)
146 return 0;
147
148 /* value comes in units of 128 µsec */
149 ret = time_to_nsec(value);
150 do_div(ret, count);
151
152 return ret;
153}
154
155#define CMF_OFF 0
156#define CMF_ON 2
157
158/*
159 * Activate or deactivate the channel monitor. When area is NULL,
160 * the monitor is deactivated. The channel monitor needs to
161 * be active in order to measure subchannels, which also need
162 * to be enabled.
163 */
164static inline void cmf_activate(void *area, unsigned int onoff)
165{
166 /* activate channel measurement */
167 asm volatile(
168 " lgr 1,%[r1]\n"
169 " lgr 2,%[mbo]\n"
170 " schm\n"
171 :
172 : [r1] "d" ((unsigned long)onoff), [mbo] "d" (area)
173 : "1", "2");
174}
175
176static int set_schib(struct ccw_device *cdev, u32 mme, int mbfc,
177 unsigned long address)
178{
179 struct subchannel *sch = to_subchannel(cdev->dev.parent);
180 int ret;
181
182 sch->config.mme = mme;
183 sch->config.mbfc = mbfc;
184 /* address can be either a block address or a block index */
185 if (mbfc)
186 sch->config.mba = address;
187 else
188 sch->config.mbi = address;
189
190 ret = cio_commit_config(sch);
191 if (!mme && ret == -ENODEV) {
192 /*
193 * The task was to disable measurement block updates but
194 * the subchannel is already gone. Report success.
195 */
196 ret = 0;
197 }
198 return ret;
199}
200
201struct set_schib_struct {
202 u32 mme;
203 int mbfc;
204 unsigned long address;
205 wait_queue_head_t wait;
206 int ret;
207};
208
209#define CMF_PENDING 1
210#define SET_SCHIB_TIMEOUT (10 * HZ)
211
212static int set_schib_wait(struct ccw_device *cdev, u32 mme,
213 int mbfc, unsigned long address)
214{
215 struct set_schib_struct set_data;
216 int ret = -ENODEV;
217
218 spin_lock_irq(cdev->ccwlock);
219 if (!cdev->private->cmb)
220 goto out;
221
222 ret = set_schib(cdev, mme, mbfc, address);
223 if (ret != -EBUSY)
224 goto out;
225
226 /* if the device is not online, don't even try again */
227 if (cdev->private->state != DEV_STATE_ONLINE)
228 goto out;
229
230 init_waitqueue_head(&set_data.wait);
231 set_data.mme = mme;
232 set_data.mbfc = mbfc;
233 set_data.address = address;
234 set_data.ret = CMF_PENDING;
235
236 cdev->private->state = DEV_STATE_CMFCHANGE;
237 cdev->private->cmb_wait = &set_data;
238 spin_unlock_irq(cdev->ccwlock);
239
240 ret = wait_event_interruptible_timeout(set_data.wait,
241 set_data.ret != CMF_PENDING,
242 SET_SCHIB_TIMEOUT);
243 spin_lock_irq(cdev->ccwlock);
244 if (ret <= 0) {
245 if (set_data.ret == CMF_PENDING) {
246 set_data.ret = (ret == 0) ? -ETIME : ret;
247 if (cdev->private->state == DEV_STATE_CMFCHANGE)
248 cdev->private->state = DEV_STATE_ONLINE;
249 }
250 }
251 cdev->private->cmb_wait = NULL;
252 ret = set_data.ret;
253out:
254 spin_unlock_irq(cdev->ccwlock);
255 return ret;
256}
257
258void retry_set_schib(struct ccw_device *cdev)
259{
260 struct set_schib_struct *set_data = cdev->private->cmb_wait;
261
262 if (!set_data)
263 return;
264
265 set_data->ret = set_schib(cdev, set_data->mme, set_data->mbfc,
266 set_data->address);
267 wake_up(&set_data->wait);
268}
269
270static int cmf_copy_block(struct ccw_device *cdev)
271{
272 struct subchannel *sch = to_subchannel(cdev->dev.parent);
273 struct cmb_data *cmb_data;
274 void *hw_block;
275
276 if (cio_update_schib(sch))
277 return -ENODEV;
278
279 if (scsw_fctl(&sch->schib.scsw) & SCSW_FCTL_START_FUNC) {
280 /* Don't copy if a start function is in progress. */
281 if ((!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_SUSPENDED)) &&
282 (scsw_actl(&sch->schib.scsw) &
283 (SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT)) &&
284 (!(scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_SEC_STATUS)))
285 return -EBUSY;
286 }
287 cmb_data = cdev->private->cmb;
288 hw_block = cmb_data->hw_block;
289 memcpy(cmb_data->last_block, hw_block, cmb_data->size);
290 cmb_data->last_update = get_tod_clock();
291 return 0;
292}
293
294struct copy_block_struct {
295 wait_queue_head_t wait;
296 int ret;
297};
298
299static int cmf_cmb_copy_wait(struct ccw_device *cdev)
300{
301 struct copy_block_struct copy_block;
302 int ret = -ENODEV;
303
304 spin_lock_irq(cdev->ccwlock);
305 if (!cdev->private->cmb)
306 goto out;
307
308 ret = cmf_copy_block(cdev);
309 if (ret != -EBUSY)
310 goto out;
311
312 if (cdev->private->state != DEV_STATE_ONLINE)
313 goto out;
314
315 init_waitqueue_head(©_block.wait);
316 copy_block.ret = CMF_PENDING;
317
318 cdev->private->state = DEV_STATE_CMFUPDATE;
319 cdev->private->cmb_wait = ©_block;
320 spin_unlock_irq(cdev->ccwlock);
321
322 ret = wait_event_interruptible(copy_block.wait,
323 copy_block.ret != CMF_PENDING);
324 spin_lock_irq(cdev->ccwlock);
325 if (ret) {
326 if (copy_block.ret == CMF_PENDING) {
327 copy_block.ret = -ERESTARTSYS;
328 if (cdev->private->state == DEV_STATE_CMFUPDATE)
329 cdev->private->state = DEV_STATE_ONLINE;
330 }
331 }
332 cdev->private->cmb_wait = NULL;
333 ret = copy_block.ret;
334out:
335 spin_unlock_irq(cdev->ccwlock);
336 return ret;
337}
338
339void cmf_retry_copy_block(struct ccw_device *cdev)
340{
341 struct copy_block_struct *copy_block = cdev->private->cmb_wait;
342
343 if (!copy_block)
344 return;
345
346 copy_block->ret = cmf_copy_block(cdev);
347 wake_up(©_block->wait);
348}
349
350static void cmf_generic_reset(struct ccw_device *cdev)
351{
352 struct cmb_data *cmb_data;
353
354 spin_lock_irq(cdev->ccwlock);
355 cmb_data = cdev->private->cmb;
356 if (cmb_data) {
357 memset(cmb_data->last_block, 0, cmb_data->size);
358 /*
359 * Need to reset hw block as well to make the hardware start
360 * from 0 again.
361 */
362 memset(cmb_data->hw_block, 0, cmb_data->size);
363 cmb_data->last_update = 0;
364 }
365 cdev->private->cmb_start_time = get_tod_clock();
366 spin_unlock_irq(cdev->ccwlock);
367}
368
369/**
370 * struct cmb_area - container for global cmb data
371 *
372 * @mem: pointer to CMBs (only in basic measurement mode)
373 * @list: contains a linked list of all subchannels
374 * @num_channels: number of channels to be measured
375 * @lock: protect concurrent access to @mem and @list
376 */
377struct cmb_area {
378 struct cmb *mem;
379 struct list_head list;
380 int num_channels;
381 spinlock_t lock;
382};
383
384static struct cmb_area cmb_area = {
385 .lock = __SPIN_LOCK_UNLOCKED(cmb_area.lock),
386 .list = LIST_HEAD_INIT(cmb_area.list),
387 .num_channels = 1024,
388};
389
390/* ****** old style CMB handling ********/
391
392/*
393 * Basic channel measurement blocks are allocated in one contiguous
394 * block of memory, which can not be moved as long as any channel
395 * is active. Therefore, a maximum number of subchannels needs to
396 * be defined somewhere. This is a module parameter, defaulting to
397 * a reasonable value of 1024, or 32 kb of memory.
398 * Current kernels don't allow kmalloc with more than 128kb, so the
399 * maximum is 4096.
400 */
401
402module_param_named(maxchannels, cmb_area.num_channels, uint, 0444);
403
404/**
405 * struct cmb - basic channel measurement block
406 * @ssch_rsch_count: number of ssch and rsch
407 * @sample_count: number of samples
408 * @device_connect_time: time of device connect
409 * @function_pending_time: time of function pending
410 * @device_disconnect_time: time of device disconnect
411 * @control_unit_queuing_time: time of control unit queuing
412 * @device_active_only_time: time of device active only
413 * @reserved: unused in basic measurement mode
414 *
415 * The measurement block as used by the hardware. The fields are described
416 * further in z/Architecture Principles of Operation, chapter 17.
417 *
418 * The cmb area made up from these blocks must be a contiguous array and may
419 * not be reallocated or freed.
420 * Only one cmb area can be present in the system.
421 */
422struct cmb {
423 u16 ssch_rsch_count;
424 u16 sample_count;
425 u32 device_connect_time;
426 u32 function_pending_time;
427 u32 device_disconnect_time;
428 u32 control_unit_queuing_time;
429 u32 device_active_only_time;
430 u32 reserved[2];
431};
432
433/*
434 * Insert a single device into the cmb_area list.
435 * Called with cmb_area.lock held from alloc_cmb.
436 */
437static int alloc_cmb_single(struct ccw_device *cdev,
438 struct cmb_data *cmb_data)
439{
440 struct cmb *cmb;
441 struct ccw_device_private *node;
442 int ret;
443
444 spin_lock_irq(cdev->ccwlock);
445 if (!list_empty(&cdev->private->cmb_list)) {
446 ret = -EBUSY;
447 goto out;
448 }
449
450 /*
451 * Find first unused cmb in cmb_area.mem.
452 * This is a little tricky: cmb_area.list
453 * remains sorted by ->cmb->hw_data pointers.
454 */
455 cmb = cmb_area.mem;
456 list_for_each_entry(node, &cmb_area.list, cmb_list) {
457 struct cmb_data *data;
458 data = node->cmb;
459 if ((struct cmb*)data->hw_block > cmb)
460 break;
461 cmb++;
462 }
463 if (cmb - cmb_area.mem >= cmb_area.num_channels) {
464 ret = -ENOMEM;
465 goto out;
466 }
467
468 /* insert new cmb */
469 list_add_tail(&cdev->private->cmb_list, &node->cmb_list);
470 cmb_data->hw_block = cmb;
471 cdev->private->cmb = cmb_data;
472 ret = 0;
473out:
474 spin_unlock_irq(cdev->ccwlock);
475 return ret;
476}
477
478static int alloc_cmb(struct ccw_device *cdev)
479{
480 int ret;
481 struct cmb *mem;
482 ssize_t size;
483 struct cmb_data *cmb_data;
484
485 /* Allocate private cmb_data. */
486 cmb_data = kzalloc(sizeof(struct cmb_data), GFP_KERNEL);
487 if (!cmb_data)
488 return -ENOMEM;
489
490 cmb_data->last_block = kzalloc(sizeof(struct cmb), GFP_KERNEL);
491 if (!cmb_data->last_block) {
492 kfree(cmb_data);
493 return -ENOMEM;
494 }
495 cmb_data->size = sizeof(struct cmb);
496 spin_lock(&cmb_area.lock);
497
498 if (!cmb_area.mem) {
499 /* there is no user yet, so we need a new area */
500 size = sizeof(struct cmb) * cmb_area.num_channels;
501 WARN_ON(!list_empty(&cmb_area.list));
502
503 spin_unlock(&cmb_area.lock);
504 mem = (void*)__get_free_pages(GFP_KERNEL | GFP_DMA,
505 get_order(size));
506 spin_lock(&cmb_area.lock);
507
508 if (cmb_area.mem) {
509 /* ok, another thread was faster */
510 free_pages((unsigned long)mem, get_order(size));
511 } else if (!mem) {
512 /* no luck */
513 ret = -ENOMEM;
514 goto out;
515 } else {
516 /* everything ok */
517 memset(mem, 0, size);
518 cmb_area.mem = mem;
519 cmf_activate(cmb_area.mem, CMF_ON);
520 }
521 }
522
523 /* do the actual allocation */
524 ret = alloc_cmb_single(cdev, cmb_data);
525out:
526 spin_unlock(&cmb_area.lock);
527 if (ret) {
528 kfree(cmb_data->last_block);
529 kfree(cmb_data);
530 }
531 return ret;
532}
533
534static void free_cmb(struct ccw_device *cdev)
535{
536 struct ccw_device_private *priv;
537 struct cmb_data *cmb_data;
538
539 spin_lock(&cmb_area.lock);
540 spin_lock_irq(cdev->ccwlock);
541
542 priv = cdev->private;
543 cmb_data = priv->cmb;
544 priv->cmb = NULL;
545 if (cmb_data)
546 kfree(cmb_data->last_block);
547 kfree(cmb_data);
548 list_del_init(&priv->cmb_list);
549
550 if (list_empty(&cmb_area.list)) {
551 ssize_t size;
552 size = sizeof(struct cmb) * cmb_area.num_channels;
553 cmf_activate(NULL, CMF_OFF);
554 free_pages((unsigned long)cmb_area.mem, get_order(size));
555 cmb_area.mem = NULL;
556 }
557 spin_unlock_irq(cdev->ccwlock);
558 spin_unlock(&cmb_area.lock);
559}
560
561static int set_cmb(struct ccw_device *cdev, u32 mme)
562{
563 u16 offset;
564 struct cmb_data *cmb_data;
565 unsigned long flags;
566
567 spin_lock_irqsave(cdev->ccwlock, flags);
568 if (!cdev->private->cmb) {
569 spin_unlock_irqrestore(cdev->ccwlock, flags);
570 return -EINVAL;
571 }
572 cmb_data = cdev->private->cmb;
573 offset = mme ? (struct cmb *)cmb_data->hw_block - cmb_area.mem : 0;
574 spin_unlock_irqrestore(cdev->ccwlock, flags);
575
576 return set_schib_wait(cdev, mme, 0, offset);
577}
578
579/* calculate utilization in 0.1 percent units */
580static u64 __cmb_utilization(u64 device_connect_time, u64 function_pending_time,
581 u64 device_disconnect_time, u64 start_time)
582{
583 u64 utilization, elapsed_time;
584
585 utilization = time_to_nsec(device_connect_time +
586 function_pending_time +
587 device_disconnect_time);
588
589 elapsed_time = get_tod_clock() - start_time;
590 elapsed_time = tod_to_ns(elapsed_time);
591 elapsed_time /= 1000;
592
593 return elapsed_time ? (utilization / elapsed_time) : 0;
594}
595
596static u64 read_cmb(struct ccw_device *cdev, int index)
597{
598 struct cmb_data *cmb_data;
599 unsigned long flags;
600 struct cmb *cmb;
601 u64 ret = 0;
602 u32 val;
603
604 spin_lock_irqsave(cdev->ccwlock, flags);
605 cmb_data = cdev->private->cmb;
606 if (!cmb_data)
607 goto out;
608
609 cmb = cmb_data->hw_block;
610 switch (index) {
611 case avg_utilization:
612 ret = __cmb_utilization(cmb->device_connect_time,
613 cmb->function_pending_time,
614 cmb->device_disconnect_time,
615 cdev->private->cmb_start_time);
616 goto out;
617 case cmb_ssch_rsch_count:
618 ret = cmb->ssch_rsch_count;
619 goto out;
620 case cmb_sample_count:
621 ret = cmb->sample_count;
622 goto out;
623 case cmb_device_connect_time:
624 val = cmb->device_connect_time;
625 break;
626 case cmb_function_pending_time:
627 val = cmb->function_pending_time;
628 break;
629 case cmb_device_disconnect_time:
630 val = cmb->device_disconnect_time;
631 break;
632 case cmb_control_unit_queuing_time:
633 val = cmb->control_unit_queuing_time;
634 break;
635 case cmb_device_active_only_time:
636 val = cmb->device_active_only_time;
637 break;
638 default:
639 goto out;
640 }
641 ret = time_to_avg_nsec(val, cmb->sample_count);
642out:
643 spin_unlock_irqrestore(cdev->ccwlock, flags);
644 return ret;
645}
646
647static int readall_cmb(struct ccw_device *cdev, struct cmbdata *data)
648{
649 struct cmb *cmb;
650 struct cmb_data *cmb_data;
651 u64 time;
652 unsigned long flags;
653 int ret;
654
655 ret = cmf_cmb_copy_wait(cdev);
656 if (ret < 0)
657 return ret;
658 spin_lock_irqsave(cdev->ccwlock, flags);
659 cmb_data = cdev->private->cmb;
660 if (!cmb_data) {
661 ret = -ENODEV;
662 goto out;
663 }
664 if (cmb_data->last_update == 0) {
665 ret = -EAGAIN;
666 goto out;
667 }
668 cmb = cmb_data->last_block;
669 time = cmb_data->last_update - cdev->private->cmb_start_time;
670
671 memset(data, 0, sizeof(struct cmbdata));
672
673 /* we only know values before device_busy_time */
674 data->size = offsetof(struct cmbdata, device_busy_time);
675
676 data->elapsed_time = tod_to_ns(time);
677
678 /* copy data to new structure */
679 data->ssch_rsch_count = cmb->ssch_rsch_count;
680 data->sample_count = cmb->sample_count;
681
682 /* time fields are converted to nanoseconds while copying */
683 data->device_connect_time = time_to_nsec(cmb->device_connect_time);
684 data->function_pending_time = time_to_nsec(cmb->function_pending_time);
685 data->device_disconnect_time =
686 time_to_nsec(cmb->device_disconnect_time);
687 data->control_unit_queuing_time
688 = time_to_nsec(cmb->control_unit_queuing_time);
689 data->device_active_only_time
690 = time_to_nsec(cmb->device_active_only_time);
691 ret = 0;
692out:
693 spin_unlock_irqrestore(cdev->ccwlock, flags);
694 return ret;
695}
696
697static void reset_cmb(struct ccw_device *cdev)
698{
699 cmf_generic_reset(cdev);
700}
701
702static int cmf_enabled(struct ccw_device *cdev)
703{
704 int enabled;
705
706 spin_lock_irq(cdev->ccwlock);
707 enabled = !!cdev->private->cmb;
708 spin_unlock_irq(cdev->ccwlock);
709
710 return enabled;
711}
712
713static struct attribute_group cmf_attr_group;
714
715static struct cmb_operations cmbops_basic = {
716 .alloc = alloc_cmb,
717 .free = free_cmb,
718 .set = set_cmb,
719 .read = read_cmb,
720 .readall = readall_cmb,
721 .reset = reset_cmb,
722 .attr_group = &cmf_attr_group,
723};
724
725/* ******** extended cmb handling ********/
726
727/**
728 * struct cmbe - extended channel measurement block
729 * @ssch_rsch_count: number of ssch and rsch
730 * @sample_count: number of samples
731 * @device_connect_time: time of device connect
732 * @function_pending_time: time of function pending
733 * @device_disconnect_time: time of device disconnect
734 * @control_unit_queuing_time: time of control unit queuing
735 * @device_active_only_time: time of device active only
736 * @device_busy_time: time of device busy
737 * @initial_command_response_time: initial command response time
738 * @reserved: unused
739 *
740 * The measurement block as used by the hardware. May be in any 64 bit physical
741 * location.
742 * The fields are described further in z/Architecture Principles of Operation,
743 * third edition, chapter 17.
744 */
745struct cmbe {
746 u32 ssch_rsch_count;
747 u32 sample_count;
748 u32 device_connect_time;
749 u32 function_pending_time;
750 u32 device_disconnect_time;
751 u32 control_unit_queuing_time;
752 u32 device_active_only_time;
753 u32 device_busy_time;
754 u32 initial_command_response_time;
755 u32 reserved[7];
756} __packed __aligned(64);
757
758static struct kmem_cache *cmbe_cache;
759
760static int alloc_cmbe(struct ccw_device *cdev)
761{
762 struct cmb_data *cmb_data;
763 struct cmbe *cmbe;
764 int ret = -ENOMEM;
765
766 cmbe = kmem_cache_zalloc(cmbe_cache, GFP_KERNEL);
767 if (!cmbe)
768 return ret;
769
770 cmb_data = kzalloc(sizeof(*cmb_data), GFP_KERNEL);
771 if (!cmb_data)
772 goto out_free;
773
774 cmb_data->last_block = kzalloc(sizeof(struct cmbe), GFP_KERNEL);
775 if (!cmb_data->last_block)
776 goto out_free;
777
778 cmb_data->size = sizeof(*cmbe);
779 cmb_data->hw_block = cmbe;
780
781 spin_lock(&cmb_area.lock);
782 spin_lock_irq(cdev->ccwlock);
783 if (cdev->private->cmb)
784 goto out_unlock;
785
786 cdev->private->cmb = cmb_data;
787
788 /* activate global measurement if this is the first channel */
789 if (list_empty(&cmb_area.list))
790 cmf_activate(NULL, CMF_ON);
791 list_add_tail(&cdev->private->cmb_list, &cmb_area.list);
792
793 spin_unlock_irq(cdev->ccwlock);
794 spin_unlock(&cmb_area.lock);
795 return 0;
796
797out_unlock:
798 spin_unlock_irq(cdev->ccwlock);
799 spin_unlock(&cmb_area.lock);
800 ret = -EBUSY;
801out_free:
802 if (cmb_data)
803 kfree(cmb_data->last_block);
804 kfree(cmb_data);
805 kmem_cache_free(cmbe_cache, cmbe);
806
807 return ret;
808}
809
810static void free_cmbe(struct ccw_device *cdev)
811{
812 struct cmb_data *cmb_data;
813
814 spin_lock(&cmb_area.lock);
815 spin_lock_irq(cdev->ccwlock);
816 cmb_data = cdev->private->cmb;
817 cdev->private->cmb = NULL;
818 if (cmb_data) {
819 kfree(cmb_data->last_block);
820 kmem_cache_free(cmbe_cache, cmb_data->hw_block);
821 }
822 kfree(cmb_data);
823
824 /* deactivate global measurement if this is the last channel */
825 list_del_init(&cdev->private->cmb_list);
826 if (list_empty(&cmb_area.list))
827 cmf_activate(NULL, CMF_OFF);
828 spin_unlock_irq(cdev->ccwlock);
829 spin_unlock(&cmb_area.lock);
830}
831
832static int set_cmbe(struct ccw_device *cdev, u32 mme)
833{
834 unsigned long mba;
835 struct cmb_data *cmb_data;
836 unsigned long flags;
837
838 spin_lock_irqsave(cdev->ccwlock, flags);
839 if (!cdev->private->cmb) {
840 spin_unlock_irqrestore(cdev->ccwlock, flags);
841 return -EINVAL;
842 }
843 cmb_data = cdev->private->cmb;
844 mba = mme ? (unsigned long) cmb_data->hw_block : 0;
845 spin_unlock_irqrestore(cdev->ccwlock, flags);
846
847 return set_schib_wait(cdev, mme, 1, mba);
848}
849
850static u64 read_cmbe(struct ccw_device *cdev, int index)
851{
852 struct cmb_data *cmb_data;
853 unsigned long flags;
854 struct cmbe *cmb;
855 u64 ret = 0;
856 u32 val;
857
858 spin_lock_irqsave(cdev->ccwlock, flags);
859 cmb_data = cdev->private->cmb;
860 if (!cmb_data)
861 goto out;
862
863 cmb = cmb_data->hw_block;
864 switch (index) {
865 case avg_utilization:
866 ret = __cmb_utilization(cmb->device_connect_time,
867 cmb->function_pending_time,
868 cmb->device_disconnect_time,
869 cdev->private->cmb_start_time);
870 goto out;
871 case cmb_ssch_rsch_count:
872 ret = cmb->ssch_rsch_count;
873 goto out;
874 case cmb_sample_count:
875 ret = cmb->sample_count;
876 goto out;
877 case cmb_device_connect_time:
878 val = cmb->device_connect_time;
879 break;
880 case cmb_function_pending_time:
881 val = cmb->function_pending_time;
882 break;
883 case cmb_device_disconnect_time:
884 val = cmb->device_disconnect_time;
885 break;
886 case cmb_control_unit_queuing_time:
887 val = cmb->control_unit_queuing_time;
888 break;
889 case cmb_device_active_only_time:
890 val = cmb->device_active_only_time;
891 break;
892 case cmb_device_busy_time:
893 val = cmb->device_busy_time;
894 break;
895 case cmb_initial_command_response_time:
896 val = cmb->initial_command_response_time;
897 break;
898 default:
899 goto out;
900 }
901 ret = time_to_avg_nsec(val, cmb->sample_count);
902out:
903 spin_unlock_irqrestore(cdev->ccwlock, flags);
904 return ret;
905}
906
907static int readall_cmbe(struct ccw_device *cdev, struct cmbdata *data)
908{
909 struct cmbe *cmb;
910 struct cmb_data *cmb_data;
911 u64 time;
912 unsigned long flags;
913 int ret;
914
915 ret = cmf_cmb_copy_wait(cdev);
916 if (ret < 0)
917 return ret;
918 spin_lock_irqsave(cdev->ccwlock, flags);
919 cmb_data = cdev->private->cmb;
920 if (!cmb_data) {
921 ret = -ENODEV;
922 goto out;
923 }
924 if (cmb_data->last_update == 0) {
925 ret = -EAGAIN;
926 goto out;
927 }
928 time = cmb_data->last_update - cdev->private->cmb_start_time;
929
930 memset (data, 0, sizeof(struct cmbdata));
931
932 /* we only know values before device_busy_time */
933 data->size = offsetof(struct cmbdata, device_busy_time);
934
935 data->elapsed_time = tod_to_ns(time);
936
937 cmb = cmb_data->last_block;
938 /* copy data to new structure */
939 data->ssch_rsch_count = cmb->ssch_rsch_count;
940 data->sample_count = cmb->sample_count;
941
942 /* time fields are converted to nanoseconds while copying */
943 data->device_connect_time = time_to_nsec(cmb->device_connect_time);
944 data->function_pending_time = time_to_nsec(cmb->function_pending_time);
945 data->device_disconnect_time =
946 time_to_nsec(cmb->device_disconnect_time);
947 data->control_unit_queuing_time
948 = time_to_nsec(cmb->control_unit_queuing_time);
949 data->device_active_only_time
950 = time_to_nsec(cmb->device_active_only_time);
951 data->device_busy_time = time_to_nsec(cmb->device_busy_time);
952 data->initial_command_response_time
953 = time_to_nsec(cmb->initial_command_response_time);
954
955 ret = 0;
956out:
957 spin_unlock_irqrestore(cdev->ccwlock, flags);
958 return ret;
959}
960
961static void reset_cmbe(struct ccw_device *cdev)
962{
963 cmf_generic_reset(cdev);
964}
965
966static struct attribute_group cmf_attr_group_ext;
967
968static struct cmb_operations cmbops_extended = {
969 .alloc = alloc_cmbe,
970 .free = free_cmbe,
971 .set = set_cmbe,
972 .read = read_cmbe,
973 .readall = readall_cmbe,
974 .reset = reset_cmbe,
975 .attr_group = &cmf_attr_group_ext,
976};
977
978static ssize_t cmb_show_attr(struct device *dev, char *buf, enum cmb_index idx)
979{
980 return sprintf(buf, "%lld\n",
981 (unsigned long long) cmf_read(to_ccwdev(dev), idx));
982}
983
984static ssize_t cmb_show_avg_sample_interval(struct device *dev,
985 struct device_attribute *attr,
986 char *buf)
987{
988 struct ccw_device *cdev = to_ccwdev(dev);
989 unsigned long count;
990 long interval;
991
992 count = cmf_read(cdev, cmb_sample_count);
993 spin_lock_irq(cdev->ccwlock);
994 if (count) {
995 interval = get_tod_clock() - cdev->private->cmb_start_time;
996 interval = tod_to_ns(interval);
997 interval /= count;
998 } else
999 interval = -1;
1000 spin_unlock_irq(cdev->ccwlock);
1001 return sprintf(buf, "%ld\n", interval);
1002}
1003
1004static ssize_t cmb_show_avg_utilization(struct device *dev,
1005 struct device_attribute *attr,
1006 char *buf)
1007{
1008 unsigned long u = cmf_read(to_ccwdev(dev), avg_utilization);
1009
1010 return sprintf(buf, "%02lu.%01lu%%\n", u / 10, u % 10);
1011}
1012
1013#define cmf_attr(name) \
1014static ssize_t show_##name(struct device *dev, \
1015 struct device_attribute *attr, char *buf) \
1016{ return cmb_show_attr((dev), buf, cmb_##name); } \
1017static DEVICE_ATTR(name, 0444, show_##name, NULL);
1018
1019#define cmf_attr_avg(name) \
1020static ssize_t show_avg_##name(struct device *dev, \
1021 struct device_attribute *attr, char *buf) \
1022{ return cmb_show_attr((dev), buf, cmb_##name); } \
1023static DEVICE_ATTR(avg_##name, 0444, show_avg_##name, NULL);
1024
1025cmf_attr(ssch_rsch_count);
1026cmf_attr(sample_count);
1027cmf_attr_avg(device_connect_time);
1028cmf_attr_avg(function_pending_time);
1029cmf_attr_avg(device_disconnect_time);
1030cmf_attr_avg(control_unit_queuing_time);
1031cmf_attr_avg(device_active_only_time);
1032cmf_attr_avg(device_busy_time);
1033cmf_attr_avg(initial_command_response_time);
1034
1035static DEVICE_ATTR(avg_sample_interval, 0444, cmb_show_avg_sample_interval,
1036 NULL);
1037static DEVICE_ATTR(avg_utilization, 0444, cmb_show_avg_utilization, NULL);
1038
1039static struct attribute *cmf_attributes[] = {
1040 &dev_attr_avg_sample_interval.attr,
1041 &dev_attr_avg_utilization.attr,
1042 &dev_attr_ssch_rsch_count.attr,
1043 &dev_attr_sample_count.attr,
1044 &dev_attr_avg_device_connect_time.attr,
1045 &dev_attr_avg_function_pending_time.attr,
1046 &dev_attr_avg_device_disconnect_time.attr,
1047 &dev_attr_avg_control_unit_queuing_time.attr,
1048 &dev_attr_avg_device_active_only_time.attr,
1049 NULL,
1050};
1051
1052static struct attribute_group cmf_attr_group = {
1053 .name = "cmf",
1054 .attrs = cmf_attributes,
1055};
1056
1057static struct attribute *cmf_attributes_ext[] = {
1058 &dev_attr_avg_sample_interval.attr,
1059 &dev_attr_avg_utilization.attr,
1060 &dev_attr_ssch_rsch_count.attr,
1061 &dev_attr_sample_count.attr,
1062 &dev_attr_avg_device_connect_time.attr,
1063 &dev_attr_avg_function_pending_time.attr,
1064 &dev_attr_avg_device_disconnect_time.attr,
1065 &dev_attr_avg_control_unit_queuing_time.attr,
1066 &dev_attr_avg_device_active_only_time.attr,
1067 &dev_attr_avg_device_busy_time.attr,
1068 &dev_attr_avg_initial_command_response_time.attr,
1069 NULL,
1070};
1071
1072static struct attribute_group cmf_attr_group_ext = {
1073 .name = "cmf",
1074 .attrs = cmf_attributes_ext,
1075};
1076
1077static ssize_t cmb_enable_show(struct device *dev,
1078 struct device_attribute *attr,
1079 char *buf)
1080{
1081 struct ccw_device *cdev = to_ccwdev(dev);
1082
1083 return sprintf(buf, "%d\n", cmf_enabled(cdev));
1084}
1085
1086static ssize_t cmb_enable_store(struct device *dev,
1087 struct device_attribute *attr, const char *buf,
1088 size_t c)
1089{
1090 struct ccw_device *cdev = to_ccwdev(dev);
1091 unsigned long val;
1092 int ret;
1093
1094 ret = kstrtoul(buf, 16, &val);
1095 if (ret)
1096 return ret;
1097
1098 switch (val) {
1099 case 0:
1100 ret = disable_cmf(cdev);
1101 break;
1102 case 1:
1103 ret = enable_cmf(cdev);
1104 break;
1105 default:
1106 ret = -EINVAL;
1107 }
1108
1109 return ret ? ret : c;
1110}
1111DEVICE_ATTR_RW(cmb_enable);
1112
1113/**
1114 * enable_cmf() - switch on the channel measurement for a specific device
1115 * @cdev: The ccw device to be enabled
1116 *
1117 * Enable channel measurements for @cdev. If this is called on a device
1118 * for which channel measurement is already enabled a reset of the
1119 * measurement data is triggered.
1120 * Returns: %0 for success or a negative error value.
1121 * Context:
1122 * non-atomic
1123 */
1124int enable_cmf(struct ccw_device *cdev)
1125{
1126 int ret = 0;
1127
1128 device_lock(&cdev->dev);
1129 if (cmf_enabled(cdev)) {
1130 cmbops->reset(cdev);
1131 goto out_unlock;
1132 }
1133 get_device(&cdev->dev);
1134 ret = cmbops->alloc(cdev);
1135 if (ret)
1136 goto out;
1137 cmbops->reset(cdev);
1138 ret = sysfs_create_group(&cdev->dev.kobj, cmbops->attr_group);
1139 if (ret) {
1140 cmbops->free(cdev);
1141 goto out;
1142 }
1143 ret = cmbops->set(cdev, 2);
1144 if (ret) {
1145 sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);
1146 cmbops->free(cdev);
1147 }
1148out:
1149 if (ret)
1150 put_device(&cdev->dev);
1151out_unlock:
1152 device_unlock(&cdev->dev);
1153 return ret;
1154}
1155
1156/**
1157 * __disable_cmf() - switch off the channel measurement for a specific device
1158 * @cdev: The ccw device to be disabled
1159 *
1160 * Returns: %0 for success or a negative error value.
1161 *
1162 * Context:
1163 * non-atomic, device_lock() held.
1164 */
1165int __disable_cmf(struct ccw_device *cdev)
1166{
1167 int ret;
1168
1169 ret = cmbops->set(cdev, 0);
1170 if (ret)
1171 return ret;
1172
1173 sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);
1174 cmbops->free(cdev);
1175 put_device(&cdev->dev);
1176
1177 return ret;
1178}
1179
1180/**
1181 * disable_cmf() - switch off the channel measurement for a specific device
1182 * @cdev: The ccw device to be disabled
1183 *
1184 * Returns: %0 for success or a negative error value.
1185 *
1186 * Context:
1187 * non-atomic
1188 */
1189int disable_cmf(struct ccw_device *cdev)
1190{
1191 int ret;
1192
1193 device_lock(&cdev->dev);
1194 ret = __disable_cmf(cdev);
1195 device_unlock(&cdev->dev);
1196
1197 return ret;
1198}
1199
1200/**
1201 * cmf_read() - read one value from the current channel measurement block
1202 * @cdev: the channel to be read
1203 * @index: the index of the value to be read
1204 *
1205 * Returns: The value read or %0 if the value cannot be read.
1206 *
1207 * Context:
1208 * any
1209 */
1210u64 cmf_read(struct ccw_device *cdev, int index)
1211{
1212 return cmbops->read(cdev, index);
1213}
1214
1215/**
1216 * cmf_readall() - read the current channel measurement block
1217 * @cdev: the channel to be read
1218 * @data: a pointer to a data block that will be filled
1219 *
1220 * Returns: %0 on success, a negative error value otherwise.
1221 *
1222 * Context:
1223 * any
1224 */
1225int cmf_readall(struct ccw_device *cdev, struct cmbdata *data)
1226{
1227 return cmbops->readall(cdev, data);
1228}
1229
1230/* Reenable cmf when a disconnected device becomes available again. */
1231int cmf_reenable(struct ccw_device *cdev)
1232{
1233 cmbops->reset(cdev);
1234 return cmbops->set(cdev, 2);
1235}
1236
1237/**
1238 * cmf_reactivate() - reactivate measurement block updates
1239 *
1240 * Use this during resume from hibernate.
1241 */
1242void cmf_reactivate(void)
1243{
1244 spin_lock(&cmb_area.lock);
1245 if (!list_empty(&cmb_area.list))
1246 cmf_activate(cmb_area.mem, CMF_ON);
1247 spin_unlock(&cmb_area.lock);
1248}
1249
1250static int __init init_cmbe(void)
1251{
1252 cmbe_cache = kmem_cache_create("cmbe_cache", sizeof(struct cmbe),
1253 __alignof__(struct cmbe), 0, NULL);
1254
1255 return cmbe_cache ? 0 : -ENOMEM;
1256}
1257
1258static int __init init_cmf(void)
1259{
1260 char *format_string;
1261 char *detect_string;
1262 int ret;
1263
1264 /*
1265 * If the user did not give a parameter, see if we are running on a
1266 * machine supporting extended measurement blocks, otherwise fall back
1267 * to basic mode.
1268 */
1269 if (format == CMF_AUTODETECT) {
1270 if (!css_general_characteristics.ext_mb) {
1271 format = CMF_BASIC;
1272 } else {
1273 format = CMF_EXTENDED;
1274 }
1275 detect_string = "autodetected";
1276 } else {
1277 detect_string = "parameter";
1278 }
1279
1280 switch (format) {
1281 case CMF_BASIC:
1282 format_string = "basic";
1283 cmbops = &cmbops_basic;
1284 break;
1285 case CMF_EXTENDED:
1286 format_string = "extended";
1287 cmbops = &cmbops_extended;
1288
1289 ret = init_cmbe();
1290 if (ret)
1291 return ret;
1292 break;
1293 default:
1294 return -EINVAL;
1295 }
1296 pr_info("Channel measurement facility initialized using format "
1297 "%s (mode %s)\n", format_string, detect_string);
1298 return 0;
1299}
1300device_initcall(init_cmf);
1301
1302EXPORT_SYMBOL_GPL(enable_cmf);
1303EXPORT_SYMBOL_GPL(disable_cmf);
1304EXPORT_SYMBOL_GPL(cmf_read);
1305EXPORT_SYMBOL_GPL(cmf_readall);