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cmf.c
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linux-6.19.14/drivers/s390/cio/cmf.c
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 pr_fmt(fmt) "cio: " fmt 14 15#include <linux/memblock.h> 16#include <linux/device.h> 17#include <linux/init.h> 18#include <linux/list.h> 19#include <linux/export.h> 20#include <linux/moduleparam.h> 21#include <linux/slab.h> 22#include <linux/timex.h> /* get_tod_clock() */ 23 24#include <asm/ccwdev.h> 25#include <asm/cio.h> 26#include <asm/cmb.h> 27#include <asm/div64.h> 28 29#include "cio.h" 30#include "css.h" 31#include "device.h" 32#include "ioasm.h" 33#include "chsc.h" 34 35/* 36 * parameter to enable cmf during boot, possible uses are: 37 * "s390cmf" -- enable cmf and allocate 2 MB of ram so measuring can be 38 * used on any subchannel 39 * "s390cmf=<num>" -- enable cmf and allocate enough memory to measure 40 * <num> subchannel, where <num> is an integer 41 * between 1 and 65535, default is 1024 42 */ 43#define ARGSTRING "s390cmf" 44 45/* indices for READCMB */ 46enum cmb_index { 47 avg_utilization = -1, 48 /* basic and extended format: */ 49 cmb_ssch_rsch_count = 0, 50 cmb_sample_count, 51 cmb_device_connect_time, 52 cmb_function_pending_time, 53 cmb_device_disconnect_time, 54 cmb_control_unit_queuing_time, 55 cmb_device_active_only_time, 56 /* extended format only: */ 57 cmb_device_busy_time, 58 cmb_initial_command_response_time, 59}; 60 61/** 62 * enum cmb_format - types of supported measurement block formats 63 * 64 * @CMF_BASIC: traditional channel measurement blocks supported 65 * by all machines that we run on 66 * @CMF_EXTENDED: improved format that was introduced with the z990 67 * machine 68 * @CMF_AUTODETECT: default: use extended format when running on a machine 69 * supporting extended format, otherwise fall back to 70 * basic format 71 */ 72enum cmb_format { 73 CMF_BASIC, 74 CMF_EXTENDED, 75 CMF_AUTODETECT = -1, 76}; 77 78/* 79 * format - actual format for all measurement blocks 80 * 81 * The format module parameter can be set to a value of 0 (zero) 82 * or 1, indicating basic or extended format as described for 83 * enum cmb_format. 84 */ 85static int format = CMF_AUTODETECT; 86module_param(format, bint, 0444); 87 88/** 89 * struct cmb_operations - functions to use depending on cmb_format 90 * 91 * Most of these functions operate on a struct ccw_device. There is only 92 * one instance of struct cmb_operations because the format of the measurement 93 * data is guaranteed to be the same for every ccw_device. 94 * 95 * @alloc: allocate memory for a channel measurement block, 96 * either with the help of a special pool or with kmalloc 97 * @free: free memory allocated with @alloc 98 * @set: enable or disable measurement 99 * @read: read a measurement entry at an index 100 * @readall: read a measurement block in a common format 101 * @reset: clear the data in the associated measurement block and 102 * reset its time stamp 103 */ 104struct cmb_operations { 105 int (*alloc) (struct ccw_device *); 106 void (*free) (struct ccw_device *); 107 int (*set) (struct ccw_device *, u32); 108 u64 (*read) (struct ccw_device *, int); 109 int (*readall)(struct ccw_device *, struct cmbdata *); 110 void (*reset) (struct ccw_device *); 111/* private: */ 112 struct attribute_group *attr_group; 113}; 114static struct cmb_operations *cmbops; 115 116struct cmb_data { 117 void *hw_block; /* Pointer to block updated by hardware */ 118 void *last_block; /* Last changed block copied from hardware block */ 119 int size; /* Size of hw_block and last_block */ 120 unsigned long long last_update; /* when last_block was updated */ 121}; 122 123/* 124 * Our user interface is designed in terms of nanoseconds, 125 * while the hardware measures total times in its own 126 * unit. 127 */ 128static inline u64 time_to_nsec(u32 value) 129{ 130 return ((u64)value) * 128000ull; 131} 132 133/* 134 * Users are usually interested in average times, 135 * not accumulated time. 136 * This also helps us with atomicity problems 137 * when reading single values. 138 */ 139static inline u64 time_to_avg_nsec(u32 value, u32 count) 140{ 141 u64 ret; 142 143 /* no samples yet, avoid division by 0 */ 144 if (count == 0) 145 return 0; 146 147 /* value comes in units of 128 µsec */ 148 ret = time_to_nsec(value); 149 do_div(ret, count); 150 151 return ret; 152} 153 154#define CMF_OFF 0 155#define CMF_ON 2 156 157/* 158 * Activate or deactivate the channel monitor. When area is NULL, 159 * the monitor is deactivated. The channel monitor needs to 160 * be active in order to measure subchannels, which also need 161 * to be enabled. 162 */ 163static inline void cmf_activate(void *area, unsigned int onoff) 164{ 165 /* activate channel measurement */ 166 asm volatile( 167 " lgr 1,%[r1]\n" 168 " lgr 2,%[mbo]\n" 169 " schm" 170 : 171 : [r1] "d" ((unsigned long)onoff), 172 [mbo] "d" (virt_to_phys(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, 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 sysfs_emit(buf, "%lld\n", cmf_read(to_ccwdev(dev), idx)); 980} 981 982static ssize_t cmb_show_avg_sample_interval(struct device *dev, 983 struct device_attribute *attr, 984 char *buf) 985{ 986 struct ccw_device *cdev = to_ccwdev(dev); 987 unsigned long count; 988 long interval; 989 990 count = cmf_read(cdev, cmb_sample_count); 991 spin_lock_irq(cdev->ccwlock); 992 if (count) { 993 interval = get_tod_clock() - cdev->private->cmb_start_time; 994 interval = tod_to_ns(interval); 995 interval /= count; 996 } else 997 interval = -1; 998 spin_unlock_irq(cdev->ccwlock); 999 return sysfs_emit(buf, "%ld\n", interval); 1000} 1001 1002static ssize_t cmb_show_avg_utilization(struct device *dev, 1003 struct device_attribute *attr, 1004 char *buf) 1005{ 1006 unsigned long u = cmf_read(to_ccwdev(dev), avg_utilization); 1007 1008 return sysfs_emit(buf, "%02lu.%01lu%%\n", u / 10, u % 10); 1009} 1010 1011#define cmf_attr(name) \ 1012static ssize_t show_##name(struct device *dev, \ 1013 struct device_attribute *attr, char *buf) \ 1014{ return cmb_show_attr((dev), buf, cmb_##name); } \ 1015static DEVICE_ATTR(name, 0444, show_##name, NULL); 1016 1017#define cmf_attr_avg(name) \ 1018static ssize_t show_avg_##name(struct device *dev, \ 1019 struct device_attribute *attr, char *buf) \ 1020{ return cmb_show_attr((dev), buf, cmb_##name); } \ 1021static DEVICE_ATTR(avg_##name, 0444, show_avg_##name, NULL); 1022 1023cmf_attr(ssch_rsch_count); 1024cmf_attr(sample_count); 1025cmf_attr_avg(device_connect_time); 1026cmf_attr_avg(function_pending_time); 1027cmf_attr_avg(device_disconnect_time); 1028cmf_attr_avg(control_unit_queuing_time); 1029cmf_attr_avg(device_active_only_time); 1030cmf_attr_avg(device_busy_time); 1031cmf_attr_avg(initial_command_response_time); 1032 1033static DEVICE_ATTR(avg_sample_interval, 0444, cmb_show_avg_sample_interval, 1034 NULL); 1035static DEVICE_ATTR(avg_utilization, 0444, cmb_show_avg_utilization, NULL); 1036 1037static struct attribute *cmf_attributes[] = { 1038 &dev_attr_avg_sample_interval.attr, 1039 &dev_attr_avg_utilization.attr, 1040 &dev_attr_ssch_rsch_count.attr, 1041 &dev_attr_sample_count.attr, 1042 &dev_attr_avg_device_connect_time.attr, 1043 &dev_attr_avg_function_pending_time.attr, 1044 &dev_attr_avg_device_disconnect_time.attr, 1045 &dev_attr_avg_control_unit_queuing_time.attr, 1046 &dev_attr_avg_device_active_only_time.attr, 1047 NULL, 1048}; 1049 1050static struct attribute_group cmf_attr_group = { 1051 .name = "cmf", 1052 .attrs = cmf_attributes, 1053}; 1054 1055static struct attribute *cmf_attributes_ext[] = { 1056 &dev_attr_avg_sample_interval.attr, 1057 &dev_attr_avg_utilization.attr, 1058 &dev_attr_ssch_rsch_count.attr, 1059 &dev_attr_sample_count.attr, 1060 &dev_attr_avg_device_connect_time.attr, 1061 &dev_attr_avg_function_pending_time.attr, 1062 &dev_attr_avg_device_disconnect_time.attr, 1063 &dev_attr_avg_control_unit_queuing_time.attr, 1064 &dev_attr_avg_device_active_only_time.attr, 1065 &dev_attr_avg_device_busy_time.attr, 1066 &dev_attr_avg_initial_command_response_time.attr, 1067 NULL, 1068}; 1069 1070static struct attribute_group cmf_attr_group_ext = { 1071 .name = "cmf", 1072 .attrs = cmf_attributes_ext, 1073}; 1074 1075static ssize_t cmb_enable_show(struct device *dev, 1076 struct device_attribute *attr, 1077 char *buf) 1078{ 1079 struct ccw_device *cdev = to_ccwdev(dev); 1080 1081 return sysfs_emit(buf, "%d\n", cmf_enabled(cdev)); 1082} 1083 1084static ssize_t cmb_enable_store(struct device *dev, 1085 struct device_attribute *attr, const char *buf, 1086 size_t c) 1087{ 1088 struct ccw_device *cdev = to_ccwdev(dev); 1089 unsigned long val; 1090 int ret; 1091 1092 ret = kstrtoul(buf, 16, &val); 1093 if (ret) 1094 return ret; 1095 1096 switch (val) { 1097 case 0: 1098 ret = disable_cmf(cdev); 1099 break; 1100 case 1: 1101 ret = enable_cmf(cdev); 1102 break; 1103 default: 1104 ret = -EINVAL; 1105 } 1106 1107 return ret ? ret : c; 1108} 1109DEVICE_ATTR_RW(cmb_enable); 1110 1111/** 1112 * enable_cmf() - switch on the channel measurement for a specific device 1113 * @cdev: The ccw device to be enabled 1114 * 1115 * Enable channel measurements for @cdev. If this is called on a device 1116 * for which channel measurement is already enabled a reset of the 1117 * measurement data is triggered. 1118 * Returns: %0 for success or a negative error value. 1119 * Context: 1120 * non-atomic 1121 */ 1122int enable_cmf(struct ccw_device *cdev) 1123{ 1124 int ret = 0; 1125 1126 device_lock(&cdev->dev); 1127 if (cmf_enabled(cdev)) { 1128 cmbops->reset(cdev); 1129 goto out_unlock; 1130 } 1131 get_device(&cdev->dev); 1132 ret = cmbops->alloc(cdev); 1133 if (ret) 1134 goto out; 1135 cmbops->reset(cdev); 1136 ret = sysfs_create_group(&cdev->dev.kobj, cmbops->attr_group); 1137 if (ret) { 1138 cmbops->free(cdev); 1139 goto out; 1140 } 1141 ret = cmbops->set(cdev, 2); 1142 if (ret) { 1143 sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group); 1144 cmbops->free(cdev); 1145 } 1146out: 1147 if (ret) 1148 put_device(&cdev->dev); 1149out_unlock: 1150 device_unlock(&cdev->dev); 1151 return ret; 1152} 1153 1154/** 1155 * __disable_cmf() - switch off the channel measurement for a specific device 1156 * @cdev: The ccw device to be disabled 1157 * 1158 * Returns: %0 for success or a negative error value. 1159 * 1160 * Context: 1161 * non-atomic, device_lock() held. 1162 */ 1163int __disable_cmf(struct ccw_device *cdev) 1164{ 1165 int ret; 1166 1167 ret = cmbops->set(cdev, 0); 1168 if (ret) 1169 return ret; 1170 1171 sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group); 1172 cmbops->free(cdev); 1173 put_device(&cdev->dev); 1174 1175 return ret; 1176} 1177 1178/** 1179 * disable_cmf() - switch off the channel measurement for a specific device 1180 * @cdev: The ccw device to be disabled 1181 * 1182 * Returns: %0 for success or a negative error value. 1183 * 1184 * Context: 1185 * non-atomic 1186 */ 1187int disable_cmf(struct ccw_device *cdev) 1188{ 1189 int ret; 1190 1191 device_lock(&cdev->dev); 1192 ret = __disable_cmf(cdev); 1193 device_unlock(&cdev->dev); 1194 1195 return ret; 1196} 1197 1198/** 1199 * cmf_read() - read one value from the current channel measurement block 1200 * @cdev: the channel to be read 1201 * @index: the index of the value to be read 1202 * 1203 * Returns: The value read or %0 if the value cannot be read. 1204 * 1205 * Context: 1206 * any 1207 */ 1208u64 cmf_read(struct ccw_device *cdev, int index) 1209{ 1210 return cmbops->read(cdev, index); 1211} 1212 1213/** 1214 * cmf_readall() - read the current channel measurement block 1215 * @cdev: the channel to be read 1216 * @data: a pointer to a data block that will be filled 1217 * 1218 * Returns: %0 on success, a negative error value otherwise. 1219 * 1220 * Context: 1221 * any 1222 */ 1223int cmf_readall(struct ccw_device *cdev, struct cmbdata *data) 1224{ 1225 return cmbops->readall(cdev, data); 1226} 1227 1228/* Re-enable cmf when a disconnected device becomes available again. */ 1229int cmf_reenable(struct ccw_device *cdev) 1230{ 1231 cmbops->reset(cdev); 1232 return cmbops->set(cdev, 2); 1233} 1234 1235/** 1236 * cmf_reactivate() - reactivate measurement block updates 1237 * 1238 * Use this during resume from hibernate. 1239 */ 1240void cmf_reactivate(void) 1241{ 1242 spin_lock(&cmb_area.lock); 1243 if (!list_empty(&cmb_area.list)) 1244 cmf_activate(cmb_area.mem, CMF_ON); 1245 spin_unlock(&cmb_area.lock); 1246} 1247 1248static int __init init_cmbe(void) 1249{ 1250 cmbe_cache = kmem_cache_create("cmbe_cache", sizeof(struct cmbe), 1251 __alignof__(struct cmbe), 0, NULL); 1252 1253 return cmbe_cache ? 0 : -ENOMEM; 1254} 1255 1256static int __init init_cmf(void) 1257{ 1258 char *format_string; 1259 char *detect_string; 1260 int ret; 1261 1262 /* 1263 * If the user did not give a parameter, see if we are running on a 1264 * machine supporting extended measurement blocks, otherwise fall back 1265 * to basic mode. 1266 */ 1267 if (format == CMF_AUTODETECT) { 1268 if (!css_general_characteristics.ext_mb) { 1269 format = CMF_BASIC; 1270 } else { 1271 format = CMF_EXTENDED; 1272 } 1273 detect_string = "autodetected"; 1274 } else { 1275 detect_string = "parameter"; 1276 } 1277 1278 switch (format) { 1279 case CMF_BASIC: 1280 format_string = "basic"; 1281 cmbops = &cmbops_basic; 1282 break; 1283 case CMF_EXTENDED: 1284 format_string = "extended"; 1285 cmbops = &cmbops_extended; 1286 1287 ret = init_cmbe(); 1288 if (ret) 1289 return ret; 1290 break; 1291 default: 1292 return -EINVAL; 1293 } 1294 pr_info("Channel measurement facility initialized using format " 1295 "%s (mode %s)\n", format_string, detect_string); 1296 return 0; 1297} 1298device_initcall(init_cmf); 1299 1300EXPORT_SYMBOL_GPL(enable_cmf); 1301EXPORT_SYMBOL_GPL(disable_cmf); 1302EXPORT_SYMBOL_GPL(cmf_read); 1303EXPORT_SYMBOL_GPL(cmf_readall);
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