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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 register void * __gpr2 asm("2");
167 register long __gpr1 asm("1");
168
169 __gpr2 = area;
170 __gpr1 = onoff;
171 /* activate channel measurement */
172 asm("schm" : : "d" (__gpr2), "d" (__gpr1) );
173}
174
175static int set_schib(struct ccw_device *cdev, u32 mme, int mbfc,
176 unsigned long address)
177{
178 struct subchannel *sch = to_subchannel(cdev->dev.parent);
179 int ret;
180
181 sch->config.mme = mme;
182 sch->config.mbfc = mbfc;
183 /* address can be either a block address or a block index */
184 if (mbfc)
185 sch->config.mba = address;
186 else
187 sch->config.mbi = address;
188
189 ret = cio_commit_config(sch);
190 if (!mme && ret == -ENODEV) {
191 /*
192 * The task was to disable measurement block updates but
193 * the subchannel is already gone. Report success.
194 */
195 ret = 0;
196 }
197 return ret;
198}
199
200struct set_schib_struct {
201 u32 mme;
202 int mbfc;
203 unsigned long address;
204 wait_queue_head_t wait;
205 int ret;
206};
207
208#define CMF_PENDING 1
209#define SET_SCHIB_TIMEOUT (10 * HZ)
210
211static int set_schib_wait(struct ccw_device *cdev, u32 mme,
212 int mbfc, unsigned long address)
213{
214 struct set_schib_struct set_data;
215 int ret = -ENODEV;
216
217 spin_lock_irq(cdev->ccwlock);
218 if (!cdev->private->cmb)
219 goto out;
220
221 ret = set_schib(cdev, mme, mbfc, address);
222 if (ret != -EBUSY)
223 goto out;
224
225 /* if the device is not online, don't even try again */
226 if (cdev->private->state != DEV_STATE_ONLINE)
227 goto out;
228
229 init_waitqueue_head(&set_data.wait);
230 set_data.mme = mme;
231 set_data.mbfc = mbfc;
232 set_data.address = address;
233 set_data.ret = CMF_PENDING;
234
235 cdev->private->state = DEV_STATE_CMFCHANGE;
236 cdev->private->cmb_wait = &set_data;
237 spin_unlock_irq(cdev->ccwlock);
238
239 ret = wait_event_interruptible_timeout(set_data.wait,
240 set_data.ret != CMF_PENDING,
241 SET_SCHIB_TIMEOUT);
242 spin_lock_irq(cdev->ccwlock);
243 if (ret <= 0) {
244 if (set_data.ret == CMF_PENDING) {
245 set_data.ret = (ret == 0) ? -ETIME : ret;
246 if (cdev->private->state == DEV_STATE_CMFCHANGE)
247 cdev->private->state = DEV_STATE_ONLINE;
248 }
249 }
250 cdev->private->cmb_wait = NULL;
251 ret = set_data.ret;
252out:
253 spin_unlock_irq(cdev->ccwlock);
254 return ret;
255}
256
257void retry_set_schib(struct ccw_device *cdev)
258{
259 struct set_schib_struct *set_data = cdev->private->cmb_wait;
260
261 if (!set_data)
262 return;
263
264 set_data->ret = set_schib(cdev, set_data->mme, set_data->mbfc,
265 set_data->address);
266 wake_up(&set_data->wait);
267}
268
269static int cmf_copy_block(struct ccw_device *cdev)
270{
271 struct subchannel *sch = to_subchannel(cdev->dev.parent);
272 struct cmb_data *cmb_data;
273 void *hw_block;
274
275 if (cio_update_schib(sch))
276 return -ENODEV;
277
278 if (scsw_fctl(&sch->schib.scsw) & SCSW_FCTL_START_FUNC) {
279 /* Don't copy if a start function is in progress. */
280 if ((!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_SUSPENDED)) &&
281 (scsw_actl(&sch->schib.scsw) &
282 (SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT)) &&
283 (!(scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_SEC_STATUS)))
284 return -EBUSY;
285 }
286 cmb_data = cdev->private->cmb;
287 hw_block = cmb_data->hw_block;
288 memcpy(cmb_data->last_block, hw_block, cmb_data->size);
289 cmb_data->last_update = get_tod_clock();
290 return 0;
291}
292
293struct copy_block_struct {
294 wait_queue_head_t wait;
295 int ret;
296};
297
298static int cmf_cmb_copy_wait(struct ccw_device *cdev)
299{
300 struct copy_block_struct copy_block;
301 int ret = -ENODEV;
302
303 spin_lock_irq(cdev->ccwlock);
304 if (!cdev->private->cmb)
305 goto out;
306
307 ret = cmf_copy_block(cdev);
308 if (ret != -EBUSY)
309 goto out;
310
311 if (cdev->private->state != DEV_STATE_ONLINE)
312 goto out;
313
314 init_waitqueue_head(©_block.wait);
315 copy_block.ret = CMF_PENDING;
316
317 cdev->private->state = DEV_STATE_CMFUPDATE;
318 cdev->private->cmb_wait = ©_block;
319 spin_unlock_irq(cdev->ccwlock);
320
321 ret = wait_event_interruptible(copy_block.wait,
322 copy_block.ret != CMF_PENDING);
323 spin_lock_irq(cdev->ccwlock);
324 if (ret) {
325 if (copy_block.ret == CMF_PENDING) {
326 copy_block.ret = -ERESTARTSYS;
327 if (cdev->private->state == DEV_STATE_CMFUPDATE)
328 cdev->private->state = DEV_STATE_ONLINE;
329 }
330 }
331 cdev->private->cmb_wait = NULL;
332 ret = copy_block.ret;
333out:
334 spin_unlock_irq(cdev->ccwlock);
335 return ret;
336}
337
338void cmf_retry_copy_block(struct ccw_device *cdev)
339{
340 struct copy_block_struct *copy_block = cdev->private->cmb_wait;
341
342 if (!copy_block)
343 return;
344
345 copy_block->ret = cmf_copy_block(cdev);
346 wake_up(©_block->wait);
347}
348
349static void cmf_generic_reset(struct ccw_device *cdev)
350{
351 struct cmb_data *cmb_data;
352
353 spin_lock_irq(cdev->ccwlock);
354 cmb_data = cdev->private->cmb;
355 if (cmb_data) {
356 memset(cmb_data->last_block, 0, cmb_data->size);
357 /*
358 * Need to reset hw block as well to make the hardware start
359 * from 0 again.
360 */
361 memset(cmb_data->hw_block, 0, cmb_data->size);
362 cmb_data->last_update = 0;
363 }
364 cdev->private->cmb_start_time = get_tod_clock();
365 spin_unlock_irq(cdev->ccwlock);
366}
367
368/**
369 * struct cmb_area - container for global cmb data
370 *
371 * @mem: pointer to CMBs (only in basic measurement mode)
372 * @list: contains a linked list of all subchannels
373 * @num_channels: number of channels to be measured
374 * @lock: protect concurrent access to @mem and @list
375 */
376struct cmb_area {
377 struct cmb *mem;
378 struct list_head list;
379 int num_channels;
380 spinlock_t lock;
381};
382
383static struct cmb_area cmb_area = {
384 .lock = __SPIN_LOCK_UNLOCKED(cmb_area.lock),
385 .list = LIST_HEAD_INIT(cmb_area.list),
386 .num_channels = 1024,
387};
388
389/* ****** old style CMB handling ********/
390
391/*
392 * Basic channel measurement blocks are allocated in one contiguous
393 * block of memory, which can not be moved as long as any channel
394 * is active. Therefore, a maximum number of subchannels needs to
395 * be defined somewhere. This is a module parameter, defaulting to
396 * a reasonable value of 1024, or 32 kb of memory.
397 * Current kernels don't allow kmalloc with more than 128kb, so the
398 * maximum is 4096.
399 */
400
401module_param_named(maxchannels, cmb_area.num_channels, uint, 0444);
402
403/**
404 * struct cmb - basic channel measurement block
405 * @ssch_rsch_count: number of ssch and rsch
406 * @sample_count: number of samples
407 * @device_connect_time: time of device connect
408 * @function_pending_time: time of function pending
409 * @device_disconnect_time: time of device disconnect
410 * @control_unit_queuing_time: time of control unit queuing
411 * @device_active_only_time: time of device active only
412 * @reserved: unused in basic measurement mode
413 *
414 * The measurement block as used by the hardware. The fields are described
415 * further in z/Architecture Principles of Operation, chapter 17.
416 *
417 * The cmb area made up from these blocks must be a contiguous array and may
418 * not be reallocated or freed.
419 * Only one cmb area can be present in the system.
420 */
421struct cmb {
422 u16 ssch_rsch_count;
423 u16 sample_count;
424 u32 device_connect_time;
425 u32 function_pending_time;
426 u32 device_disconnect_time;
427 u32 control_unit_queuing_time;
428 u32 device_active_only_time;
429 u32 reserved[2];
430};
431
432/*
433 * Insert a single device into the cmb_area list.
434 * Called with cmb_area.lock held from alloc_cmb.
435 */
436static int alloc_cmb_single(struct ccw_device *cdev,
437 struct cmb_data *cmb_data)
438{
439 struct cmb *cmb;
440 struct ccw_device_private *node;
441 int ret;
442
443 spin_lock_irq(cdev->ccwlock);
444 if (!list_empty(&cdev->private->cmb_list)) {
445 ret = -EBUSY;
446 goto out;
447 }
448
449 /*
450 * Find first unused cmb in cmb_area.mem.
451 * This is a little tricky: cmb_area.list
452 * remains sorted by ->cmb->hw_data pointers.
453 */
454 cmb = cmb_area.mem;
455 list_for_each_entry(node, &cmb_area.list, cmb_list) {
456 struct cmb_data *data;
457 data = node->cmb;
458 if ((struct cmb*)data->hw_block > cmb)
459 break;
460 cmb++;
461 }
462 if (cmb - cmb_area.mem >= cmb_area.num_channels) {
463 ret = -ENOMEM;
464 goto out;
465 }
466
467 /* insert new cmb */
468 list_add_tail(&cdev->private->cmb_list, &node->cmb_list);
469 cmb_data->hw_block = cmb;
470 cdev->private->cmb = cmb_data;
471 ret = 0;
472out:
473 spin_unlock_irq(cdev->ccwlock);
474 return ret;
475}
476
477static int alloc_cmb(struct ccw_device *cdev)
478{
479 int ret;
480 struct cmb *mem;
481 ssize_t size;
482 struct cmb_data *cmb_data;
483
484 /* Allocate private cmb_data. */
485 cmb_data = kzalloc(sizeof(struct cmb_data), GFP_KERNEL);
486 if (!cmb_data)
487 return -ENOMEM;
488
489 cmb_data->last_block = kzalloc(sizeof(struct cmb), GFP_KERNEL);
490 if (!cmb_data->last_block) {
491 kfree(cmb_data);
492 return -ENOMEM;
493 }
494 cmb_data->size = sizeof(struct cmb);
495 spin_lock(&cmb_area.lock);
496
497 if (!cmb_area.mem) {
498 /* there is no user yet, so we need a new area */
499 size = sizeof(struct cmb) * cmb_area.num_channels;
500 WARN_ON(!list_empty(&cmb_area.list));
501
502 spin_unlock(&cmb_area.lock);
503 mem = (void*)__get_free_pages(GFP_KERNEL | GFP_DMA,
504 get_order(size));
505 spin_lock(&cmb_area.lock);
506
507 if (cmb_area.mem) {
508 /* ok, another thread was faster */
509 free_pages((unsigned long)mem, get_order(size));
510 } else if (!mem) {
511 /* no luck */
512 ret = -ENOMEM;
513 goto out;
514 } else {
515 /* everything ok */
516 memset(mem, 0, size);
517 cmb_area.mem = mem;
518 cmf_activate(cmb_area.mem, CMF_ON);
519 }
520 }
521
522 /* do the actual allocation */
523 ret = alloc_cmb_single(cdev, cmb_data);
524out:
525 spin_unlock(&cmb_area.lock);
526 if (ret) {
527 kfree(cmb_data->last_block);
528 kfree(cmb_data);
529 }
530 return ret;
531}
532
533static void free_cmb(struct ccw_device *cdev)
534{
535 struct ccw_device_private *priv;
536 struct cmb_data *cmb_data;
537
538 spin_lock(&cmb_area.lock);
539 spin_lock_irq(cdev->ccwlock);
540
541 priv = cdev->private;
542 cmb_data = priv->cmb;
543 priv->cmb = NULL;
544 if (cmb_data)
545 kfree(cmb_data->last_block);
546 kfree(cmb_data);
547 list_del_init(&priv->cmb_list);
548
549 if (list_empty(&cmb_area.list)) {
550 ssize_t size;
551 size = sizeof(struct cmb) * cmb_area.num_channels;
552 cmf_activate(NULL, CMF_OFF);
553 free_pages((unsigned long)cmb_area.mem, get_order(size));
554 cmb_area.mem = NULL;
555 }
556 spin_unlock_irq(cdev->ccwlock);
557 spin_unlock(&cmb_area.lock);
558}
559
560static int set_cmb(struct ccw_device *cdev, u32 mme)
561{
562 u16 offset;
563 struct cmb_data *cmb_data;
564 unsigned long flags;
565
566 spin_lock_irqsave(cdev->ccwlock, flags);
567 if (!cdev->private->cmb) {
568 spin_unlock_irqrestore(cdev->ccwlock, flags);
569 return -EINVAL;
570 }
571 cmb_data = cdev->private->cmb;
572 offset = mme ? (struct cmb *)cmb_data->hw_block - cmb_area.mem : 0;
573 spin_unlock_irqrestore(cdev->ccwlock, flags);
574
575 return set_schib_wait(cdev, mme, 0, offset);
576}
577
578/* calculate utilization in 0.1 percent units */
579static u64 __cmb_utilization(u64 device_connect_time, u64 function_pending_time,
580 u64 device_disconnect_time, u64 start_time)
581{
582 u64 utilization, elapsed_time;
583
584 utilization = time_to_nsec(device_connect_time +
585 function_pending_time +
586 device_disconnect_time);
587
588 elapsed_time = get_tod_clock() - start_time;
589 elapsed_time = tod_to_ns(elapsed_time);
590 elapsed_time /= 1000;
591
592 return elapsed_time ? (utilization / elapsed_time) : 0;
593}
594
595static u64 read_cmb(struct ccw_device *cdev, int index)
596{
597 struct cmb_data *cmb_data;
598 unsigned long flags;
599 struct cmb *cmb;
600 u64 ret = 0;
601 u32 val;
602
603 spin_lock_irqsave(cdev->ccwlock, flags);
604 cmb_data = cdev->private->cmb;
605 if (!cmb_data)
606 goto out;
607
608 cmb = cmb_data->hw_block;
609 switch (index) {
610 case avg_utilization:
611 ret = __cmb_utilization(cmb->device_connect_time,
612 cmb->function_pending_time,
613 cmb->device_disconnect_time,
614 cdev->private->cmb_start_time);
615 goto out;
616 case cmb_ssch_rsch_count:
617 ret = cmb->ssch_rsch_count;
618 goto out;
619 case cmb_sample_count:
620 ret = cmb->sample_count;
621 goto out;
622 case cmb_device_connect_time:
623 val = cmb->device_connect_time;
624 break;
625 case cmb_function_pending_time:
626 val = cmb->function_pending_time;
627 break;
628 case cmb_device_disconnect_time:
629 val = cmb->device_disconnect_time;
630 break;
631 case cmb_control_unit_queuing_time:
632 val = cmb->control_unit_queuing_time;
633 break;
634 case cmb_device_active_only_time:
635 val = cmb->device_active_only_time;
636 break;
637 default:
638 goto out;
639 }
640 ret = time_to_avg_nsec(val, cmb->sample_count);
641out:
642 spin_unlock_irqrestore(cdev->ccwlock, flags);
643 return ret;
644}
645
646static int readall_cmb(struct ccw_device *cdev, struct cmbdata *data)
647{
648 struct cmb *cmb;
649 struct cmb_data *cmb_data;
650 u64 time;
651 unsigned long flags;
652 int ret;
653
654 ret = cmf_cmb_copy_wait(cdev);
655 if (ret < 0)
656 return ret;
657 spin_lock_irqsave(cdev->ccwlock, flags);
658 cmb_data = cdev->private->cmb;
659 if (!cmb_data) {
660 ret = -ENODEV;
661 goto out;
662 }
663 if (cmb_data->last_update == 0) {
664 ret = -EAGAIN;
665 goto out;
666 }
667 cmb = cmb_data->last_block;
668 time = cmb_data->last_update - cdev->private->cmb_start_time;
669
670 memset(data, 0, sizeof(struct cmbdata));
671
672 /* we only know values before device_busy_time */
673 data->size = offsetof(struct cmbdata, device_busy_time);
674
675 data->elapsed_time = tod_to_ns(time);
676
677 /* copy data to new structure */
678 data->ssch_rsch_count = cmb->ssch_rsch_count;
679 data->sample_count = cmb->sample_count;
680
681 /* time fields are converted to nanoseconds while copying */
682 data->device_connect_time = time_to_nsec(cmb->device_connect_time);
683 data->function_pending_time = time_to_nsec(cmb->function_pending_time);
684 data->device_disconnect_time =
685 time_to_nsec(cmb->device_disconnect_time);
686 data->control_unit_queuing_time
687 = time_to_nsec(cmb->control_unit_queuing_time);
688 data->device_active_only_time
689 = time_to_nsec(cmb->device_active_only_time);
690 ret = 0;
691out:
692 spin_unlock_irqrestore(cdev->ccwlock, flags);
693 return ret;
694}
695
696static void reset_cmb(struct ccw_device *cdev)
697{
698 cmf_generic_reset(cdev);
699}
700
701static int cmf_enabled(struct ccw_device *cdev)
702{
703 int enabled;
704
705 spin_lock_irq(cdev->ccwlock);
706 enabled = !!cdev->private->cmb;
707 spin_unlock_irq(cdev->ccwlock);
708
709 return enabled;
710}
711
712static struct attribute_group cmf_attr_group;
713
714static struct cmb_operations cmbops_basic = {
715 .alloc = alloc_cmb,
716 .free = free_cmb,
717 .set = set_cmb,
718 .read = read_cmb,
719 .readall = readall_cmb,
720 .reset = reset_cmb,
721 .attr_group = &cmf_attr_group,
722};
723
724/* ******** extended cmb handling ********/
725
726/**
727 * struct cmbe - extended channel measurement block
728 * @ssch_rsch_count: number of ssch and rsch
729 * @sample_count: number of samples
730 * @device_connect_time: time of device connect
731 * @function_pending_time: time of function pending
732 * @device_disconnect_time: time of device disconnect
733 * @control_unit_queuing_time: time of control unit queuing
734 * @device_active_only_time: time of device active only
735 * @device_busy_time: time of device busy
736 * @initial_command_response_time: initial command response time
737 * @reserved: unused
738 *
739 * The measurement block as used by the hardware. May be in any 64 bit physical
740 * location.
741 * The fields are described further in z/Architecture Principles of Operation,
742 * third edition, chapter 17.
743 */
744struct cmbe {
745 u32 ssch_rsch_count;
746 u32 sample_count;
747 u32 device_connect_time;
748 u32 function_pending_time;
749 u32 device_disconnect_time;
750 u32 control_unit_queuing_time;
751 u32 device_active_only_time;
752 u32 device_busy_time;
753 u32 initial_command_response_time;
754 u32 reserved[7];
755} __packed __aligned(64);
756
757static struct kmem_cache *cmbe_cache;
758
759static int alloc_cmbe(struct ccw_device *cdev)
760{
761 struct cmb_data *cmb_data;
762 struct cmbe *cmbe;
763 int ret = -ENOMEM;
764
765 cmbe = kmem_cache_zalloc(cmbe_cache, GFP_KERNEL);
766 if (!cmbe)
767 return ret;
768
769 cmb_data = kzalloc(sizeof(*cmb_data), GFP_KERNEL);
770 if (!cmb_data)
771 goto out_free;
772
773 cmb_data->last_block = kzalloc(sizeof(struct cmbe), GFP_KERNEL);
774 if (!cmb_data->last_block)
775 goto out_free;
776
777 cmb_data->size = sizeof(*cmbe);
778 cmb_data->hw_block = cmbe;
779
780 spin_lock(&cmb_area.lock);
781 spin_lock_irq(cdev->ccwlock);
782 if (cdev->private->cmb)
783 goto out_unlock;
784
785 cdev->private->cmb = cmb_data;
786
787 /* activate global measurement if this is the first channel */
788 if (list_empty(&cmb_area.list))
789 cmf_activate(NULL, CMF_ON);
790 list_add_tail(&cdev->private->cmb_list, &cmb_area.list);
791
792 spin_unlock_irq(cdev->ccwlock);
793 spin_unlock(&cmb_area.lock);
794 return 0;
795
796out_unlock:
797 spin_unlock_irq(cdev->ccwlock);
798 spin_unlock(&cmb_area.lock);
799 ret = -EBUSY;
800out_free:
801 if (cmb_data)
802 kfree(cmb_data->last_block);
803 kfree(cmb_data);
804 kmem_cache_free(cmbe_cache, cmbe);
805
806 return ret;
807}
808
809static void free_cmbe(struct ccw_device *cdev)
810{
811 struct cmb_data *cmb_data;
812
813 spin_lock(&cmb_area.lock);
814 spin_lock_irq(cdev->ccwlock);
815 cmb_data = cdev->private->cmb;
816 cdev->private->cmb = NULL;
817 if (cmb_data) {
818 kfree(cmb_data->last_block);
819 kmem_cache_free(cmbe_cache, cmb_data->hw_block);
820 }
821 kfree(cmb_data);
822
823 /* deactivate global measurement if this is the last channel */
824 list_del_init(&cdev->private->cmb_list);
825 if (list_empty(&cmb_area.list))
826 cmf_activate(NULL, CMF_OFF);
827 spin_unlock_irq(cdev->ccwlock);
828 spin_unlock(&cmb_area.lock);
829}
830
831static int set_cmbe(struct ccw_device *cdev, u32 mme)
832{
833 unsigned long mba;
834 struct cmb_data *cmb_data;
835 unsigned long flags;
836
837 spin_lock_irqsave(cdev->ccwlock, flags);
838 if (!cdev->private->cmb) {
839 spin_unlock_irqrestore(cdev->ccwlock, flags);
840 return -EINVAL;
841 }
842 cmb_data = cdev->private->cmb;
843 mba = mme ? (unsigned long) cmb_data->hw_block : 0;
844 spin_unlock_irqrestore(cdev->ccwlock, flags);
845
846 return set_schib_wait(cdev, mme, 1, mba);
847}
848
849static u64 read_cmbe(struct ccw_device *cdev, int index)
850{
851 struct cmb_data *cmb_data;
852 unsigned long flags;
853 struct cmbe *cmb;
854 u64 ret = 0;
855 u32 val;
856
857 spin_lock_irqsave(cdev->ccwlock, flags);
858 cmb_data = cdev->private->cmb;
859 if (!cmb_data)
860 goto out;
861
862 cmb = cmb_data->hw_block;
863 switch (index) {
864 case avg_utilization:
865 ret = __cmb_utilization(cmb->device_connect_time,
866 cmb->function_pending_time,
867 cmb->device_disconnect_time,
868 cdev->private->cmb_start_time);
869 goto out;
870 case cmb_ssch_rsch_count:
871 ret = cmb->ssch_rsch_count;
872 goto out;
873 case cmb_sample_count:
874 ret = cmb->sample_count;
875 goto out;
876 case cmb_device_connect_time:
877 val = cmb->device_connect_time;
878 break;
879 case cmb_function_pending_time:
880 val = cmb->function_pending_time;
881 break;
882 case cmb_device_disconnect_time:
883 val = cmb->device_disconnect_time;
884 break;
885 case cmb_control_unit_queuing_time:
886 val = cmb->control_unit_queuing_time;
887 break;
888 case cmb_device_active_only_time:
889 val = cmb->device_active_only_time;
890 break;
891 case cmb_device_busy_time:
892 val = cmb->device_busy_time;
893 break;
894 case cmb_initial_command_response_time:
895 val = cmb->initial_command_response_time;
896 break;
897 default:
898 goto out;
899 }
900 ret = time_to_avg_nsec(val, cmb->sample_count);
901out:
902 spin_unlock_irqrestore(cdev->ccwlock, flags);
903 return ret;
904}
905
906static int readall_cmbe(struct ccw_device *cdev, struct cmbdata *data)
907{
908 struct cmbe *cmb;
909 struct cmb_data *cmb_data;
910 u64 time;
911 unsigned long flags;
912 int ret;
913
914 ret = cmf_cmb_copy_wait(cdev);
915 if (ret < 0)
916 return ret;
917 spin_lock_irqsave(cdev->ccwlock, flags);
918 cmb_data = cdev->private->cmb;
919 if (!cmb_data) {
920 ret = -ENODEV;
921 goto out;
922 }
923 if (cmb_data->last_update == 0) {
924 ret = -EAGAIN;
925 goto out;
926 }
927 time = cmb_data->last_update - cdev->private->cmb_start_time;
928
929 memset (data, 0, sizeof(struct cmbdata));
930
931 /* we only know values before device_busy_time */
932 data->size = offsetof(struct cmbdata, device_busy_time);
933
934 data->elapsed_time = tod_to_ns(time);
935
936 cmb = cmb_data->last_block;
937 /* copy data to new structure */
938 data->ssch_rsch_count = cmb->ssch_rsch_count;
939 data->sample_count = cmb->sample_count;
940
941 /* time fields are converted to nanoseconds while copying */
942 data->device_connect_time = time_to_nsec(cmb->device_connect_time);
943 data->function_pending_time = time_to_nsec(cmb->function_pending_time);
944 data->device_disconnect_time =
945 time_to_nsec(cmb->device_disconnect_time);
946 data->control_unit_queuing_time
947 = time_to_nsec(cmb->control_unit_queuing_time);
948 data->device_active_only_time
949 = time_to_nsec(cmb->device_active_only_time);
950 data->device_busy_time = time_to_nsec(cmb->device_busy_time);
951 data->initial_command_response_time
952 = time_to_nsec(cmb->initial_command_response_time);
953
954 ret = 0;
955out:
956 spin_unlock_irqrestore(cdev->ccwlock, flags);
957 return ret;
958}
959
960static void reset_cmbe(struct ccw_device *cdev)
961{
962 cmf_generic_reset(cdev);
963}
964
965static struct attribute_group cmf_attr_group_ext;
966
967static struct cmb_operations cmbops_extended = {
968 .alloc = alloc_cmbe,
969 .free = free_cmbe,
970 .set = set_cmbe,
971 .read = read_cmbe,
972 .readall = readall_cmbe,
973 .reset = reset_cmbe,
974 .attr_group = &cmf_attr_group_ext,
975};
976
977static ssize_t cmb_show_attr(struct device *dev, char *buf, enum cmb_index idx)
978{
979 return sprintf(buf, "%lld\n",
980 (unsigned long long) cmf_read(to_ccwdev(dev), idx));
981}
982
983static ssize_t cmb_show_avg_sample_interval(struct device *dev,
984 struct device_attribute *attr,
985 char *buf)
986{
987 struct ccw_device *cdev = to_ccwdev(dev);
988 unsigned long count;
989 long interval;
990
991 count = cmf_read(cdev, cmb_sample_count);
992 spin_lock_irq(cdev->ccwlock);
993 if (count) {
994 interval = get_tod_clock() - cdev->private->cmb_start_time;
995 interval = tod_to_ns(interval);
996 interval /= count;
997 } else
998 interval = -1;
999 spin_unlock_irq(cdev->ccwlock);
1000 return sprintf(buf, "%ld\n", interval);
1001}
1002
1003static ssize_t cmb_show_avg_utilization(struct device *dev,
1004 struct device_attribute *attr,
1005 char *buf)
1006{
1007 unsigned long u = cmf_read(to_ccwdev(dev), avg_utilization);
1008
1009 return sprintf(buf, "%02lu.%01lu%%\n", u / 10, u % 10);
1010}
1011
1012#define cmf_attr(name) \
1013static ssize_t show_##name(struct device *dev, \
1014 struct device_attribute *attr, char *buf) \
1015{ return cmb_show_attr((dev), buf, cmb_##name); } \
1016static DEVICE_ATTR(name, 0444, show_##name, NULL);
1017
1018#define cmf_attr_avg(name) \
1019static ssize_t show_avg_##name(struct device *dev, \
1020 struct device_attribute *attr, char *buf) \
1021{ return cmb_show_attr((dev), buf, cmb_##name); } \
1022static DEVICE_ATTR(avg_##name, 0444, show_avg_##name, NULL);
1023
1024cmf_attr(ssch_rsch_count);
1025cmf_attr(sample_count);
1026cmf_attr_avg(device_connect_time);
1027cmf_attr_avg(function_pending_time);
1028cmf_attr_avg(device_disconnect_time);
1029cmf_attr_avg(control_unit_queuing_time);
1030cmf_attr_avg(device_active_only_time);
1031cmf_attr_avg(device_busy_time);
1032cmf_attr_avg(initial_command_response_time);
1033
1034static DEVICE_ATTR(avg_sample_interval, 0444, cmb_show_avg_sample_interval,
1035 NULL);
1036static DEVICE_ATTR(avg_utilization, 0444, cmb_show_avg_utilization, NULL);
1037
1038static struct attribute *cmf_attributes[] = {
1039 &dev_attr_avg_sample_interval.attr,
1040 &dev_attr_avg_utilization.attr,
1041 &dev_attr_ssch_rsch_count.attr,
1042 &dev_attr_sample_count.attr,
1043 &dev_attr_avg_device_connect_time.attr,
1044 &dev_attr_avg_function_pending_time.attr,
1045 &dev_attr_avg_device_disconnect_time.attr,
1046 &dev_attr_avg_control_unit_queuing_time.attr,
1047 &dev_attr_avg_device_active_only_time.attr,
1048 NULL,
1049};
1050
1051static struct attribute_group cmf_attr_group = {
1052 .name = "cmf",
1053 .attrs = cmf_attributes,
1054};
1055
1056static struct attribute *cmf_attributes_ext[] = {
1057 &dev_attr_avg_sample_interval.attr,
1058 &dev_attr_avg_utilization.attr,
1059 &dev_attr_ssch_rsch_count.attr,
1060 &dev_attr_sample_count.attr,
1061 &dev_attr_avg_device_connect_time.attr,
1062 &dev_attr_avg_function_pending_time.attr,
1063 &dev_attr_avg_device_disconnect_time.attr,
1064 &dev_attr_avg_control_unit_queuing_time.attr,
1065 &dev_attr_avg_device_active_only_time.attr,
1066 &dev_attr_avg_device_busy_time.attr,
1067 &dev_attr_avg_initial_command_response_time.attr,
1068 NULL,
1069};
1070
1071static struct attribute_group cmf_attr_group_ext = {
1072 .name = "cmf",
1073 .attrs = cmf_attributes_ext,
1074};
1075
1076static ssize_t cmb_enable_show(struct device *dev,
1077 struct device_attribute *attr,
1078 char *buf)
1079{
1080 struct ccw_device *cdev = to_ccwdev(dev);
1081
1082 return sprintf(buf, "%d\n", cmf_enabled(cdev));
1083}
1084
1085static ssize_t cmb_enable_store(struct device *dev,
1086 struct device_attribute *attr, const char *buf,
1087 size_t c)
1088{
1089 struct ccw_device *cdev = to_ccwdev(dev);
1090 unsigned long val;
1091 int ret;
1092
1093 ret = kstrtoul(buf, 16, &val);
1094 if (ret)
1095 return ret;
1096
1097 switch (val) {
1098 case 0:
1099 ret = disable_cmf(cdev);
1100 break;
1101 case 1:
1102 ret = enable_cmf(cdev);
1103 break;
1104 default:
1105 ret = -EINVAL;
1106 }
1107
1108 return ret ? ret : c;
1109}
1110DEVICE_ATTR_RW(cmb_enable);
1111
1112int ccw_set_cmf(struct ccw_device *cdev, int enable)
1113{
1114 return cmbops->set(cdev, enable ? 2 : 0);
1115}
1116
1117/**
1118 * enable_cmf() - switch on the channel measurement for a specific device
1119 * @cdev: The ccw device to be enabled
1120 *
1121 * Enable channel measurements for @cdev. If this is called on a device
1122 * for which channel measurement is already enabled a reset of the
1123 * measurement data is triggered.
1124 * Returns: %0 for success or a negative error value.
1125 * Context:
1126 * non-atomic
1127 */
1128int enable_cmf(struct ccw_device *cdev)
1129{
1130 int ret = 0;
1131
1132 device_lock(&cdev->dev);
1133 if (cmf_enabled(cdev)) {
1134 cmbops->reset(cdev);
1135 goto out_unlock;
1136 }
1137 get_device(&cdev->dev);
1138 ret = cmbops->alloc(cdev);
1139 if (ret)
1140 goto out;
1141 cmbops->reset(cdev);
1142 ret = sysfs_create_group(&cdev->dev.kobj, cmbops->attr_group);
1143 if (ret) {
1144 cmbops->free(cdev);
1145 goto out;
1146 }
1147 ret = cmbops->set(cdev, 2);
1148 if (ret) {
1149 sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);
1150 cmbops->free(cdev);
1151 }
1152out:
1153 if (ret)
1154 put_device(&cdev->dev);
1155out_unlock:
1156 device_unlock(&cdev->dev);
1157 return ret;
1158}
1159
1160/**
1161 * __disable_cmf() - switch off the channel measurement for a specific device
1162 * @cdev: The ccw device to be disabled
1163 *
1164 * Returns: %0 for success or a negative error value.
1165 *
1166 * Context:
1167 * non-atomic, device_lock() held.
1168 */
1169int __disable_cmf(struct ccw_device *cdev)
1170{
1171 int ret;
1172
1173 ret = cmbops->set(cdev, 0);
1174 if (ret)
1175 return ret;
1176
1177 sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);
1178 cmbops->free(cdev);
1179 put_device(&cdev->dev);
1180
1181 return ret;
1182}
1183
1184/**
1185 * disable_cmf() - switch off the channel measurement for a specific device
1186 * @cdev: The ccw device to be disabled
1187 *
1188 * Returns: %0 for success or a negative error value.
1189 *
1190 * Context:
1191 * non-atomic
1192 */
1193int disable_cmf(struct ccw_device *cdev)
1194{
1195 int ret;
1196
1197 device_lock(&cdev->dev);
1198 ret = __disable_cmf(cdev);
1199 device_unlock(&cdev->dev);
1200
1201 return ret;
1202}
1203
1204/**
1205 * cmf_read() - read one value from the current channel measurement block
1206 * @cdev: the channel to be read
1207 * @index: the index of the value to be read
1208 *
1209 * Returns: The value read or %0 if the value cannot be read.
1210 *
1211 * Context:
1212 * any
1213 */
1214u64 cmf_read(struct ccw_device *cdev, int index)
1215{
1216 return cmbops->read(cdev, index);
1217}
1218
1219/**
1220 * cmf_readall() - read the current channel measurement block
1221 * @cdev: the channel to be read
1222 * @data: a pointer to a data block that will be filled
1223 *
1224 * Returns: %0 on success, a negative error value otherwise.
1225 *
1226 * Context:
1227 * any
1228 */
1229int cmf_readall(struct ccw_device *cdev, struct cmbdata *data)
1230{
1231 return cmbops->readall(cdev, data);
1232}
1233
1234/* Reenable cmf when a disconnected device becomes available again. */
1235int cmf_reenable(struct ccw_device *cdev)
1236{
1237 cmbops->reset(cdev);
1238 return cmbops->set(cdev, 2);
1239}
1240
1241/**
1242 * cmf_reactivate() - reactivate measurement block updates
1243 *
1244 * Use this during resume from hibernate.
1245 */
1246void cmf_reactivate(void)
1247{
1248 spin_lock(&cmb_area.lock);
1249 if (!list_empty(&cmb_area.list))
1250 cmf_activate(cmb_area.mem, CMF_ON);
1251 spin_unlock(&cmb_area.lock);
1252}
1253
1254static int __init init_cmbe(void)
1255{
1256 cmbe_cache = kmem_cache_create("cmbe_cache", sizeof(struct cmbe),
1257 __alignof__(struct cmbe), 0, NULL);
1258
1259 return cmbe_cache ? 0 : -ENOMEM;
1260}
1261
1262static int __init init_cmf(void)
1263{
1264 char *format_string;
1265 char *detect_string;
1266 int ret;
1267
1268 /*
1269 * If the user did not give a parameter, see if we are running on a
1270 * machine supporting extended measurement blocks, otherwise fall back
1271 * to basic mode.
1272 */
1273 if (format == CMF_AUTODETECT) {
1274 if (!css_general_characteristics.ext_mb) {
1275 format = CMF_BASIC;
1276 } else {
1277 format = CMF_EXTENDED;
1278 }
1279 detect_string = "autodetected";
1280 } else {
1281 detect_string = "parameter";
1282 }
1283
1284 switch (format) {
1285 case CMF_BASIC:
1286 format_string = "basic";
1287 cmbops = &cmbops_basic;
1288 break;
1289 case CMF_EXTENDED:
1290 format_string = "extended";
1291 cmbops = &cmbops_extended;
1292
1293 ret = init_cmbe();
1294 if (ret)
1295 return ret;
1296 break;
1297 default:
1298 return -EINVAL;
1299 }
1300 pr_info("Channel measurement facility initialized using format "
1301 "%s (mode %s)\n", format_string, detect_string);
1302 return 0;
1303}
1304device_initcall(init_cmf);
1305
1306EXPORT_SYMBOL_GPL(enable_cmf);
1307EXPORT_SYMBOL_GPL(disable_cmf);
1308EXPORT_SYMBOL_GPL(cmf_read);
1309EXPORT_SYMBOL_GPL(cmf_readall);