drivers/s390/cio/cmf.c

   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 #include <linux/bootmem.h>
  29 #include <linux/device.h>
  30 #include <linux/init.h>
  31 #include <linux/list.h>
  32 #include <linux/module.h>
  33 #include <linux/moduleparam.h>
  34 #include <linux/slab.h>
  35 #include <linux/timex.h>        /* get_clock() */
  36
  37 #include <asm/ccwdev.h>
  38 #include <asm/cio.h>
  39 #include <asm/cmb.h>
  40 #include <asm/div64.h>
  41
  42 #include "cio.h"
  43 #include "css.h"
  44 #include "device.h"
  45 #include "ioasm.h"
  46 #include "chsc.h"
  47
  48 /*
  49  * parameter to enable cmf during boot, possible uses are:
  50  *  "s390cmf" -- enable cmf and allocate 2 MB of ram so measuring can be
  51  *               used on any subchannel
  52  *  "s390cmf=<num>" -- enable cmf and allocate enough memory to measure
  53  *                     <num> subchannel, where <num> is an integer
  54  *                     between 1 and 65535, default is 1024
  55  */
  56 #define ARGSTRING "s390cmf"
  57
  58 /* indices for READCMB */
  59 enum cmb_index {
  60  /* basic and exended format: */
  61         cmb_ssch_rsch_count,
  62         cmb_sample_count,
  63         cmb_device_connect_time,
  64         cmb_function_pending_time,
  65         cmb_device_disconnect_time,
  66         cmb_control_unit_queuing_time,
  67         cmb_device_active_only_time,
  68  /* extended format only: */
  69         cmb_device_busy_time,
  70         cmb_initial_command_response_time,
  71 };
  72
  73 /**
  74  * enum cmb_format - types of supported measurement block formats
  75  *
  76  * @CMF_BASIC:      traditional channel measurement blocks supported
  77  *                  by all machines that we run on
  78  * @CMF_EXTENDED:   improved format that was introduced with the z990
  79  *                  machine
  80  * @CMF_AUTODETECT: default: use extended format when running on a machine
  81  *                  supporting extended format, otherwise fall back to
  82  *                  basic format
  83  */
  84 enum cmb_format {
  85         CMF_BASIC,
  86         CMF_EXTENDED,
  87         CMF_AUTODETECT = -1,
  88 };
  89
  90 /*
  91  * format - actual format for all measurement blocks
  92  *
  93  * The format module parameter can be set to a value of 0 (zero)
  94  * or 1, indicating basic or extended format as described for
  95  * enum cmb_format.
  96  */
  97 static int format = CMF_AUTODETECT;
  98 module_param(format, bool, 0444);
  99
 100 /**
 101  * struct cmb_operations - functions to use depending on cmb_format
 102  *
 103  * Most of these functions operate on a struct ccw_device. There is only
 104  * one instance of struct cmb_operations because the format of the measurement
 105  * data is guaranteed to be the same for every ccw_device.
 106  *
 107  * @alloc:      allocate memory for a channel measurement block,
 108  *              either with the help of a special pool or with kmalloc
 109  * @free:       free memory allocated with @alloc
 110  * @set:        enable or disable measurement
 111  * @read:       read a measurement entry at an index
 112  * @readall:    read a measurement block in a common format
 113  * @reset:      clear the data in the associated measurement block and
 114  *              reset its time stamp
 115  * @align:      align an allocated block so that the hardware can use it
 116  */
 117 struct cmb_operations {
 118         int  (*alloc)  (struct ccw_device *);
 119         void (*free)   (struct ccw_device *);
 120         int  (*set)    (struct ccw_device *, u32);
 121         u64  (*read)   (struct ccw_device *, int);
 122         int  (*readall)(struct ccw_device *, struct cmbdata *);
 123         void (*reset)  (struct ccw_device *);
 124         void *(*align) (void *);
 125 /* private: */
 126         struct attribute_group *attr_group;
 127 };
 128 static struct cmb_operations *cmbops;
 129
 130 struct cmb_data {
 131         void *hw_block;   /* Pointer to block updated by hardware */
 132         void *last_block; /* Last changed block copied from hardware block */
 133         int size;         /* Size of hw_block and last_block */
 134         unsigned long long last_update;  /* when last_block was updated */
 135 };
 136
 137 /*
 138  * Our user interface is designed in terms of nanoseconds,
 139  * while the hardware measures total times in its own
 140  * unit.
 141  */
 142 static inline u64 time_to_nsec(u32 value)
 143 {
 144         return ((u64)value) * 128000ull;
 145 }
 146
 147 /*
 148  * Users are usually interested in average times,
 149  * not accumulated time.
 150  * This also helps us with atomicity problems
 151  * when reading sinlge values.
 152  */
 153 static inline u64 time_to_avg_nsec(u32 value, u32 count)
 154 {
 155         u64 ret;
 156
 157         /* no samples yet, avoid division by 0 */
 158         if (count == 0)
 159                 return 0;
 160
 161         /* value comes in units of 128 µsec */
 162         ret = time_to_nsec(value);
 163         do_div(ret, count);
 164
 165         return ret;
 166 }
 167
 168 /*
 169  * Activate or deactivate the channel monitor. When area is NULL,
 170  * the monitor is deactivated. The channel monitor needs to
 171  * be active in order to measure subchannels, which also need
 172  * to be enabled.
 173  */
 174 static inline void cmf_activate(void *area, unsigned int onoff)
 175 {
 176         register void * __gpr2 asm("2");
 177         register long __gpr1 asm("1");
 178
 179         __gpr2 = area;
 180         __gpr1 = onoff ? 2 : 0;
 181         /* activate channel measurement */
 182         asm("schm" : : "d" (__gpr2), "d" (__gpr1) );
 183 }
 184
 185 static int set_schib(struct ccw_device *cdev, u32 mme, int mbfc,
 186                      unsigned long address)
 187 {
 188         int ret;
 189         int retry;
 190         struct subchannel *sch;
 191         struct schib *schib;
 192
 193         sch = to_subchannel(cdev->dev.parent);
 194         schib = &sch->schib;
 195         /* msch can silently fail, so do it again if necessary */
 196         for (retry = 0; retry < 3; retry++) {
 197                 /* prepare schib */
 198                 stsch(sch->schid, schib);
 199                 schib->pmcw.mme  = mme;
 200                 schib->pmcw.mbfc = mbfc;
 201                 /* address can be either a block address or a block index */
 202                 if (mbfc)
 203                         schib->mba = address;
 204                 else
 205                         schib->pmcw.mbi = address;
 206
 207                 /* try to submit it */
 208                 switch(ret = msch_err(sch->schid, schib)) {
 209                         case 0:
 210                                 break;
 211                         case 1:
 212                         case 2: /* in I/O or status pending */
 213                                 ret = -EBUSY;
 214                                 break;
 215                         case 3: /* subchannel is no longer valid */
 216                                 ret = -ENODEV;
 217                                 break;
 218                         default: /* msch caught an exception */
 219                                 ret = -EINVAL;
 220                                 break;
 221                 }
 222                 stsch(sch->schid, schib); /* restore the schib */
 223
 224                 if (ret)
 225                         break;
 226
 227                 /* check if it worked */
 228                 if (schib->pmcw.mme  == mme &&
 229                     schib->pmcw.mbfc == mbfc &&
 230                     (mbfc ? (schib->mba == address)
 231                           : (schib->pmcw.mbi == address)))
 232                         return 0;
 233
 234                 ret = -EINVAL;
 235         }
 236
 237         return ret;
 238 }
 239
 240 struct set_schib_struct {
 241         u32 mme;
 242         int mbfc;
 243         unsigned long address;
 244         wait_queue_head_t wait;
 245         int ret;
 246         struct kref kref;
 247 };
 248
 249 static void cmf_set_schib_release(struct kref *kref)
 250 {
 251         struct set_schib_struct *set_data;
 252
 253         set_data = container_of(kref, struct set_schib_struct, kref);
 254         kfree(set_data);
 255 }
 256
 257 #define CMF_PENDING 1
 258
 259 static int set_schib_wait(struct ccw_device *cdev, u32 mme,
 260                                 int mbfc, unsigned long address)
 261 {
 262         struct set_schib_struct *set_data;
 263         int ret;
 264
 265         spin_lock_irq(cdev->ccwlock);
 266         if (!cdev->private->cmb) {
 267                 ret = -ENODEV;
 268                 goto out;
 269         }
 270         set_data = kzalloc(sizeof(struct set_schib_struct), GFP_ATOMIC);
 271         if (!set_data) {
 272                 ret = -ENOMEM;
 273                 goto out;
 274         }
 275         init_waitqueue_head(&set_data->wait);
 276         kref_init(&set_data->kref);
 277         set_data->mme = mme;
 278         set_data->mbfc = mbfc;
 279         set_data->address = address;
 280
 281         ret = set_schib(cdev, mme, mbfc, address);
 282         if (ret != -EBUSY)
 283                 goto out_put;
 284
 285         if (cdev->private->state != DEV_STATE_ONLINE) {
 286                 /* if the device is not online, don't even try again */
 287                 ret = -EBUSY;
 288                 goto out_put;
 289         }
 290
 291         cdev->private->state = DEV_STATE_CMFCHANGE;
 292         set_data->ret = CMF_PENDING;
 293         cdev->private->cmb_wait = set_data;
 294
 295         spin_unlock_irq(cdev->ccwlock);
 296         if (wait_event_interruptible(set_data->wait,
 297                                      set_data->ret != CMF_PENDING)) {
 298                 spin_lock_irq(cdev->ccwlock);
 299                 if (set_data->ret == CMF_PENDING) {
 300                         set_data->ret = -ERESTARTSYS;
 301                         if (cdev->private->state == DEV_STATE_CMFCHANGE)
 302                                 cdev->private->state = DEV_STATE_ONLINE;
 303                 }
 304                 spin_unlock_irq(cdev->ccwlock);
 305         }
 306         spin_lock_irq(cdev->ccwlock);
 307         cdev->private->cmb_wait = NULL;
 308         ret = set_data->ret;
 309 out_put:
 310         kref_put(&set_data->kref, cmf_set_schib_release);
 311 out:
 312         spin_unlock_irq(cdev->ccwlock);
 313         return ret;
 314 }
 315
 316 void retry_set_schib(struct ccw_device *cdev)
 317 {
 318         struct set_schib_struct *set_data;
 319
 320         set_data = cdev->private->cmb_wait;
 321         if (!set_data) {
 322                 WARN_ON(1);
 323                 return;
 324         }
 325         kref_get(&set_data->kref);
 326         set_data->ret = set_schib(cdev, set_data->mme, set_data->mbfc,
 327                                   set_data->address);
 328         wake_up(&set_data->wait);
 329         kref_put(&set_data->kref, cmf_set_schib_release);
 330 }
 331
 332 static int cmf_copy_block(struct ccw_device *cdev)
 333 {
 334         struct subchannel *sch;
 335         void *reference_buf;
 336         void *hw_block;
 337         struct cmb_data *cmb_data;
 338
 339         sch = to_subchannel(cdev->dev.parent);
 340
 341         if (stsch(sch->schid, &sch->schib))
 342                 return -ENODEV;
 343
 344         if (sch->schib.scsw.fctl & SCSW_FCTL_START_FUNC) {
 345                 /* Don't copy if a start function is in progress. */
 346                 if ((!sch->schib.scsw.actl & SCSW_ACTL_SUSPENDED) &&
 347                     (sch->schib.scsw.actl &
 348                      (SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT)) &&
 349                     (!sch->schib.scsw.stctl & SCSW_STCTL_SEC_STATUS))
 350                         return -EBUSY;
 351         }
 352         cmb_data = cdev->private->cmb;
 353         hw_block = cmbops->align(cmb_data->hw_block);
 354         if (!memcmp(cmb_data->last_block, hw_block, cmb_data->size))
 355                 /* No need to copy. */
 356                 return 0;
 357         reference_buf = kzalloc(cmb_data->size, GFP_ATOMIC);
 358         if (!reference_buf)
 359                 return -ENOMEM;
 360         /* Ensure consistency of block copied from hardware. */
 361         do {
 362                 memcpy(cmb_data->last_block, hw_block, cmb_data->size);
 363                 memcpy(reference_buf, hw_block, cmb_data->size);
 364         } while (memcmp(cmb_data->last_block, reference_buf, cmb_data->size));
 365         cmb_data->last_update = get_clock();
 366         kfree(reference_buf);
 367         return 0;
 368 }
 369
 370 struct copy_block_struct {
 371         wait_queue_head_t wait;
 372         int ret;
 373         struct kref kref;
 374 };
 375
 376 static void cmf_copy_block_release(struct kref *kref)
 377 {
 378         struct copy_block_struct *copy_block;
 379
 380         copy_block = container_of(kref, struct copy_block_struct, kref);
 381         kfree(copy_block);
 382 }
 383
 384 static int cmf_cmb_copy_wait(struct ccw_device *cdev)
 385 {
 386         struct copy_block_struct *copy_block;
 387         int ret;
 388         unsigned long flags;
 389
 390         spin_lock_irqsave(cdev->ccwlock, flags);
 391         if (!cdev->private->cmb) {
 392                 ret = -ENODEV;
 393                 goto out;
 394         }
 395         copy_block = kzalloc(sizeof(struct copy_block_struct), GFP_ATOMIC);
 396         if (!copy_block) {
 397                 ret = -ENOMEM;
 398                 goto out;
 399         }
 400         init_waitqueue_head(&copy_block->wait);
 401         kref_init(&copy_block->kref);
 402
 403         ret = cmf_copy_block(cdev);
 404         if (ret != -EBUSY)
 405                 goto out_put;
 406
 407         if (cdev->private->state != DEV_STATE_ONLINE) {
 408                 ret = -EBUSY;
 409                 goto out_put;
 410         }
 411
 412         cdev->private->state = DEV_STATE_CMFUPDATE;
 413         copy_block->ret = CMF_PENDING;
 414         cdev->private->cmb_wait = copy_block;
 415
 416         spin_unlock_irqrestore(cdev->ccwlock, flags);
 417         if (wait_event_interruptible(copy_block->wait,
 418                                      copy_block->ret != CMF_PENDING)) {
 419                 spin_lock_irqsave(cdev->ccwlock, flags);
 420                 if (copy_block->ret == CMF_PENDING) {
 421                         copy_block->ret = -ERESTARTSYS;
 422                         if (cdev->private->state == DEV_STATE_CMFUPDATE)
 423                                 cdev->private->state = DEV_STATE_ONLINE;
 424                 }
 425                 spin_unlock_irqrestore(cdev->ccwlock, flags);
 426         }
 427         spin_lock_irqsave(cdev->ccwlock, flags);
 428         cdev->private->cmb_wait = NULL;
 429         ret = copy_block->ret;
 430 out_put:
 431         kref_put(&copy_block->kref, cmf_copy_block_release);
 432 out:
 433         spin_unlock_irqrestore(cdev->ccwlock, flags);
 434         return ret;
 435 }
 436
 437 void cmf_retry_copy_block(struct ccw_device *cdev)
 438 {
 439         struct copy_block_struct *copy_block;
 440
 441         copy_block = cdev->private->cmb_wait;
 442         if (!copy_block) {
 443                 WARN_ON(1);
 444                 return;
 445         }
 446         kref_get(&copy_block->kref);
 447         copy_block->ret = cmf_copy_block(cdev);
 448         wake_up(&copy_block->wait);
 449         kref_put(&copy_block->kref, cmf_copy_block_release);
 450 }
 451
 452 static void cmf_generic_reset(struct ccw_device *cdev)
 453 {
 454         struct cmb_data *cmb_data;
 455
 456         spin_lock_irq(cdev->ccwlock);
 457         cmb_data = cdev->private->cmb;
 458         if (cmb_data) {
 459                 memset(cmb_data->last_block, 0, cmb_data->size);
 460                 /*
 461                  * Need to reset hw block as well to make the hardware start
 462                  * from 0 again.
 463                  */
 464                 memset(cmbops->align(cmb_data->hw_block), 0, cmb_data->size);
 465                 cmb_data->last_update = 0;
 466         }
 467         cdev->private->cmb_start_time = get_clock();
 468         spin_unlock_irq(cdev->ccwlock);
 469 }
 470
 471 /**
 472  * struct cmb_area - container for global cmb data
 473  *
 474  * @mem:        pointer to CMBs (only in basic measurement mode)
 475  * @list:       contains a linked list of all subchannels
 476  * @num_channels: number of channels to be measured
 477  * @lock:       protect concurrent access to @mem and @list
 478  */
 479 struct cmb_area {
 480         struct cmb *mem;
 481         struct list_head list;
 482         int num_channels;
 483         spinlock_t lock;
 484 };
 485
 486 static struct cmb_area cmb_area = {
 487         .lock = __SPIN_LOCK_UNLOCKED(cmb_area.lock),
 488         .list = LIST_HEAD_INIT(cmb_area.list),
 489         .num_channels  = 1024,
 490 };
 491
 492 /* ****** old style CMB handling ********/
 493
 494 /*
 495  * Basic channel measurement blocks are allocated in one contiguous
 496  * block of memory, which can not be moved as long as any channel
 497  * is active. Therefore, a maximum number of subchannels needs to
 498  * be defined somewhere. This is a module parameter, defaulting to
 499  * a resonable value of 1024, or 32 kb of memory.
 500  * Current kernels don't allow kmalloc with more than 128kb, so the
 501  * maximum is 4096.
 502  */
 503
 504 module_param_named(maxchannels, cmb_area.num_channels, uint, 0444);
 505
 506 /**
 507  * struct cmb - basic channel measurement block
 508  * @ssch_rsch_count: number of ssch and rsch
 509  * @sample_count: number of samples
 510  * @device_connect_time: time of device connect
 511  * @function_pending_time: time of function pending
 512  * @device_disconnect_time: time of device disconnect
 513  * @control_unit_queuing_time: time of control unit queuing
 514  * @device_active_only_time: time of device active only
 515  * @reserved: unused in basic measurement mode
 516  *
 517  * The measurement block as used by the hardware. The fields are described
 518  * further in z/Architecture Principles of Operation, chapter 17.
 519  *
 520  * The cmb area made up from these blocks must be a contiguous array and may
 521  * not be reallocated or freed.
 522  * Only one cmb area can be present in the system.
 523  */
 524 struct cmb {
 525         u16 ssch_rsch_count;
 526         u16 sample_count;
 527         u32 device_connect_time;
 528         u32 function_pending_time;
 529         u32 device_disconnect_time;
 530         u32 control_unit_queuing_time;
 531         u32 device_active_only_time;
 532         u32 reserved[2];
 533 };
 534
 535 /*
 536  * Insert a single device into the cmb_area list.
 537  * Called with cmb_area.lock held from alloc_cmb.
 538  */
 539 static int alloc_cmb_single(struct ccw_device *cdev,
 540                             struct cmb_data *cmb_data)
 541 {
 542         struct cmb *cmb;
 543         struct ccw_device_private *node;
 544         int ret;
 545
 546         spin_lock_irq(cdev->ccwlock);
 547         if (!list_empty(&cdev->private->cmb_list)) {
 548                 ret = -EBUSY;
 549                 goto out;
 550         }
 551
 552         /*
 553          * Find first unused cmb in cmb_area.mem.
 554          * This is a little tricky: cmb_area.list
 555          * remains sorted by ->cmb->hw_data pointers.
 556          */
 557         cmb = cmb_area.mem;
 558         list_for_each_entry(node, &cmb_area.list, cmb_list) {
 559                 struct cmb_data *data;
 560                 data = node->cmb;
 561                 if ((struct cmb*)data->hw_block > cmb)
 562                         break;
 563                 cmb++;
 564         }
 565         if (cmb - cmb_area.mem >= cmb_area.num_channels) {
 566                 ret = -ENOMEM;
 567                 goto out;
 568         }
 569
 570         /* insert new cmb */
 571         list_add_tail(&cdev->private->cmb_list, &node->cmb_list);
 572         cmb_data->hw_block = cmb;
 573         cdev->private->cmb = cmb_data;
 574         ret = 0;
 575 out:
 576         spin_unlock_irq(cdev->ccwlock);
 577         return ret;
 578 }
 579
 580 static int alloc_cmb(struct ccw_device *cdev)
 581 {
 582         int ret;
 583         struct cmb *mem;
 584         ssize_t size;
 585         struct cmb_data *cmb_data;
 586
 587         /* Allocate private cmb_data. */
 588         cmb_data = kzalloc(sizeof(struct cmb_data), GFP_KERNEL);
 589         if (!cmb_data)
 590                 return -ENOMEM;
 591
 592         cmb_data->last_block = kzalloc(sizeof(struct cmb), GFP_KERNEL);
 593         if (!cmb_data->last_block) {
 594                 kfree(cmb_data);
 595                 return -ENOMEM;
 596         }
 597         cmb_data->size = sizeof(struct cmb);
 598         spin_lock(&cmb_area.lock);
 599
 600         if (!cmb_area.mem) {
 601                 /* there is no user yet, so we need a new area */
 602                 size = sizeof(struct cmb) * cmb_area.num_channels;
 603                 WARN_ON(!list_empty(&cmb_area.list));
 604
 605                 spin_unlock(&cmb_area.lock);
 606                 mem = (void*)__get_free_pages(GFP_KERNEL | GFP_DMA,
 607                                  get_order(size));
 608                 spin_lock(&cmb_area.lock);
 609
 610                 if (cmb_area.mem) {
 611                         /* ok, another thread was faster */
 612                         free_pages((unsigned long)mem, get_order(size));
 613                 } else if (!mem) {
 614                         /* no luck */
 615                         printk(KERN_WARNING "cio: failed to allocate area "
 616                                "for measuring %d subchannels\n",
 617                                cmb_area.num_channels);
 618                         ret = -ENOMEM;
 619                         goto out;
 620                 } else {
 621                         /* everything ok */
 622                         memset(mem, 0, size);
 623                         cmb_area.mem = mem;
 624                         cmf_activate(cmb_area.mem, 1);
 625                 }
 626         }
 627
 628         /* do the actual allocation */
 629         ret = alloc_cmb_single(cdev, cmb_data);
 630 out:
 631         spin_unlock(&cmb_area.lock);
 632         if (ret) {
 633                 kfree(cmb_data->last_block);
 634                 kfree(cmb_data);
 635         }
 636         return ret;
 637 }
 638
 639 static void free_cmb(struct ccw_device *cdev)
 640 {
 641         struct ccw_device_private *priv;
 642         struct cmb_data *cmb_data;
 643
 644         spin_lock(&cmb_area.lock);
 645         spin_lock_irq(cdev->ccwlock);
 646
 647         priv = cdev->private;
 648
 649         if (list_empty(&priv->cmb_list)) {
 650                 /* already freed */
 651                 goto out;
 652         }
 653
 654         cmb_data = priv->cmb;
 655         priv->cmb = NULL;
 656         if (cmb_data)
 657                 kfree(cmb_data->last_block);
 658         kfree(cmb_data);
 659         list_del_init(&priv->cmb_list);
 660
 661         if (list_empty(&cmb_area.list)) {
 662                 ssize_t size;
 663                 size = sizeof(struct cmb) * cmb_area.num_channels;
 664                 cmf_activate(NULL, 0);
 665                 free_pages((unsigned long)cmb_area.mem, get_order(size));
 666                 cmb_area.mem = NULL;
 667         }
 668 out:
 669         spin_unlock_irq(cdev->ccwlock);
 670         spin_unlock(&cmb_area.lock);
 671 }
 672
 673 static int set_cmb(struct ccw_device *cdev, u32 mme)
 674 {
 675         u16 offset;
 676         struct cmb_data *cmb_data;
 677         unsigned long flags;
 678
 679         spin_lock_irqsave(cdev->ccwlock, flags);
 680         if (!cdev->private->cmb) {
 681                 spin_unlock_irqrestore(cdev->ccwlock, flags);
 682                 return -EINVAL;
 683         }
 684         cmb_data = cdev->private->cmb;
 685         offset = mme ? (struct cmb *)cmb_data->hw_block - cmb_area.mem : 0;
 686         spin_unlock_irqrestore(cdev->ccwlock, flags);
 687
 688         return set_schib_wait(cdev, mme, 0, offset);
 689 }
 690
 691 static u64 read_cmb(struct ccw_device *cdev, int index)
 692 {
 693         struct cmb *cmb;
 694         u32 val;
 695         int ret;
 696         unsigned long flags;
 697
 698         ret = cmf_cmb_copy_wait(cdev);
 699         if (ret < 0)
 700                 return 0;
 701
 702         spin_lock_irqsave(cdev->ccwlock, flags);
 703         if (!cdev->private->cmb) {
 704                 ret = 0;
 705                 goto out;
 706         }
 707         cmb = ((struct cmb_data *)cdev->private->cmb)->last_block;
 708
 709         switch (index) {
 710         case cmb_ssch_rsch_count:
 711                 ret = cmb->ssch_rsch_count;
 712                 goto out;
 713         case cmb_sample_count:
 714                 ret = cmb->sample_count;
 715                 goto out;
 716         case cmb_device_connect_time:
 717                 val = cmb->device_connect_time;
 718                 break;
 719         case cmb_function_pending_time:
 720                 val = cmb->function_pending_time;
 721                 break;
 722         case cmb_device_disconnect_time:
 723                 val = cmb->device_disconnect_time;
 724                 break;
 725         case cmb_control_unit_queuing_time:
 726                 val = cmb->control_unit_queuing_time;
 727                 break;
 728         case cmb_device_active_only_time:
 729                 val = cmb->device_active_only_time;
 730                 break;
 731         default:
 732                 ret = 0;
 733                 goto out;
 734         }
 735         ret = time_to_avg_nsec(val, cmb->sample_count);
 736 out:
 737         spin_unlock_irqrestore(cdev->ccwlock, flags);
 738         return ret;
 739 }
 740
 741 static int readall_cmb(struct ccw_device *cdev, struct cmbdata *data)
 742 {
 743         struct cmb *cmb;
 744         struct cmb_data *cmb_data;
 745         u64 time;
 746         unsigned long flags;
 747         int ret;
 748
 749         ret = cmf_cmb_copy_wait(cdev);
 750         if (ret < 0)
 751                 return ret;
 752         spin_lock_irqsave(cdev->ccwlock, flags);
 753         cmb_data = cdev->private->cmb;
 754         if (!cmb_data) {
 755                 ret = -ENODEV;
 756                 goto out;
 757         }
 758         if (cmb_data->last_update == 0) {
 759                 ret = -EAGAIN;
 760                 goto out;
 761         }
 762         cmb = cmb_data->last_block;
 763         time = cmb_data->last_update - cdev->private->cmb_start_time;
 764
 765         memset(data, 0, sizeof(struct cmbdata));
 766
 767         /* we only know values before device_busy_time */
 768         data->size = offsetof(struct cmbdata, device_busy_time);
 769
 770         /* convert to nanoseconds */
 771         data->elapsed_time = (time * 1000) >> 12;
 772
 773         /* copy data to new structure */
 774         data->ssch_rsch_count = cmb->ssch_rsch_count;
 775         data->sample_count = cmb->sample_count;
 776
 777         /* time fields are converted to nanoseconds while copying */
 778         data->device_connect_time = time_to_nsec(cmb->device_connect_time);
 779         data->function_pending_time = time_to_nsec(cmb->function_pending_time);
 780         data->device_disconnect_time =
 781                 time_to_nsec(cmb->device_disconnect_time);
 782         data->control_unit_queuing_time
 783                 = time_to_nsec(cmb->control_unit_queuing_time);
 784         data->device_active_only_time
 785                 = time_to_nsec(cmb->device_active_only_time);
 786         ret = 0;
 787 out:
 788         spin_unlock_irqrestore(cdev->ccwlock, flags);
 789         return ret;
 790 }
 791
 792 static void reset_cmb(struct ccw_device *cdev)
 793 {
 794         cmf_generic_reset(cdev);
 795 }
 796
 797 static void * align_cmb(void *area)
 798 {
 799         return area;
 800 }
 801
 802 static struct attribute_group cmf_attr_group;
 803
 804 static struct cmb_operations cmbops_basic = {
 805         .alloc  = alloc_cmb,
 806         .free   = free_cmb,
 807         .set    = set_cmb,
 808         .read   = read_cmb,
 809         .readall    = readall_cmb,
 810         .reset      = reset_cmb,
 811         .align      = align_cmb,
 812         .attr_group = &cmf_attr_group,
 813 };
 814
 815 /* ******** extended cmb handling ********/
 816
 817 /**
 818  * struct cmbe - extended channel measurement block
 819  * @ssch_rsch_count: number of ssch and rsch
 820  * @sample_count: number of samples
 821  * @device_connect_time: time of device connect
 822  * @function_pending_time: time of function pending
 823  * @device_disconnect_time: time of device disconnect
 824  * @control_unit_queuing_time: time of control unit queuing
 825  * @device_active_only_time: time of device active only
 826  * @device_busy_time: time of device busy
 827  * @initial_command_response_time: initial command response time
 828  * @reserved: unused
 829  *
 830  * The measurement block as used by the hardware. May be in any 64 bit physical
 831  * location.
 832  * The fields are described further in z/Architecture Principles of Operation,
 833  * third edition, chapter 17.
 834  */
 835 struct cmbe {
 836         u32 ssch_rsch_count;
 837         u32 sample_count;
 838         u32 device_connect_time;
 839         u32 function_pending_time;
 840         u32 device_disconnect_time;
 841         u32 control_unit_queuing_time;
 842         u32 device_active_only_time;
 843         u32 device_busy_time;
 844         u32 initial_command_response_time;
 845         u32 reserved[7];
 846 };
 847
 848 /*
 849  * kmalloc only guarantees 8 byte alignment, but we need cmbe
 850  * pointers to be naturally aligned. Make sure to allocate
 851  * enough space for two cmbes.
 852  */
 853 static inline struct cmbe *cmbe_align(struct cmbe *c)
 854 {
 855         unsigned long addr;
 856         addr = ((unsigned long)c + sizeof (struct cmbe) - sizeof(long)) &
 857                                  ~(sizeof (struct cmbe) - sizeof(long));
 858         return (struct cmbe*)addr;
 859 }
 860
 861 static int alloc_cmbe(struct ccw_device *cdev)
 862 {
 863         struct cmbe *cmbe;
 864         struct cmb_data *cmb_data;
 865         int ret;
 866
 867         cmbe = kzalloc (sizeof (*cmbe) * 2, GFP_KERNEL);
 868         if (!cmbe)
 869                 return -ENOMEM;
 870         cmb_data = kzalloc(sizeof(struct cmb_data), GFP_KERNEL);
 871         if (!cmb_data) {
 872                 ret = -ENOMEM;
 873                 goto out_free;
 874         }
 875         cmb_data->last_block = kzalloc(sizeof(struct cmbe), GFP_KERNEL);
 876         if (!cmb_data->last_block) {
 877                 ret = -ENOMEM;
 878                 goto out_free;
 879         }
 880         cmb_data->size = sizeof(struct cmbe);
 881         spin_lock_irq(cdev->ccwlock);
 882         if (cdev->private->cmb) {
 883                 spin_unlock_irq(cdev->ccwlock);
 884                 ret = -EBUSY;
 885                 goto out_free;
 886         }
 887         cmb_data->hw_block = cmbe;
 888         cdev->private->cmb = cmb_data;
 889         spin_unlock_irq(cdev->ccwlock);
 890
 891         /* activate global measurement if this is the first channel */
 892         spin_lock(&cmb_area.lock);
 893         if (list_empty(&cmb_area.list))
 894                 cmf_activate(NULL, 1);
 895         list_add_tail(&cdev->private->cmb_list, &cmb_area.list);
 896         spin_unlock(&cmb_area.lock);
 897
 898         return 0;
 899 out_free:
 900         if (cmb_data)
 901                 kfree(cmb_data->last_block);
 902         kfree(cmb_data);
 903         kfree(cmbe);
 904         return ret;
 905 }
 906
 907 static void free_cmbe(struct ccw_device *cdev)
 908 {
 909         struct cmb_data *cmb_data;
 910
 911         spin_lock_irq(cdev->ccwlock);
 912         cmb_data = cdev->private->cmb;
 913         cdev->private->cmb = NULL;
 914         if (cmb_data)
 915                 kfree(cmb_data->last_block);
 916         kfree(cmb_data);
 917         spin_unlock_irq(cdev->ccwlock);
 918
 919         /* deactivate global measurement if this is the last channel */
 920         spin_lock(&cmb_area.lock);
 921         list_del_init(&cdev->private->cmb_list);
 922         if (list_empty(&cmb_area.list))
 923                 cmf_activate(NULL, 0);
 924         spin_unlock(&cmb_area.lock);
 925 }
 926
 927 static int set_cmbe(struct ccw_device *cdev, u32 mme)
 928 {
 929         unsigned long mba;
 930         struct cmb_data *cmb_data;
 931         unsigned long flags;
 932
 933         spin_lock_irqsave(cdev->ccwlock, flags);
 934         if (!cdev->private->cmb) {
 935                 spin_unlock_irqrestore(cdev->ccwlock, flags);
 936                 return -EINVAL;
 937         }
 938         cmb_data = cdev->private->cmb;
 939         mba = mme ? (unsigned long) cmbe_align(cmb_data->hw_block) : 0;
 940         spin_unlock_irqrestore(cdev->ccwlock, flags);
 941
 942         return set_schib_wait(cdev, mme, 1, mba);
 943 }
 944
 945
 946 static u64 read_cmbe(struct ccw_device *cdev, int index)
 947 {
 948         struct cmbe *cmb;
 949         struct cmb_data *cmb_data;
 950         u32 val;
 951         int ret;
 952         unsigned long flags;
 953
 954         ret = cmf_cmb_copy_wait(cdev);
 955         if (ret < 0)
 956                 return 0;
 957
 958         spin_lock_irqsave(cdev->ccwlock, flags);
 959         cmb_data = cdev->private->cmb;
 960         if (!cmb_data) {
 961                 ret = 0;
 962                 goto out;
 963         }
 964         cmb = cmb_data->last_block;
 965
 966         switch (index) {
 967         case cmb_ssch_rsch_count:
 968                 ret = cmb->ssch_rsch_count;
 969                 goto out;
 970         case cmb_sample_count:
 971                 ret = cmb->sample_count;
 972                 goto out;
 973         case cmb_device_connect_time:
 974                 val = cmb->device_connect_time;
 975                 break;
 976         case cmb_function_pending_time:
 977                 val = cmb->function_pending_time;
 978                 break;
 979         case cmb_device_disconnect_time:
 980                 val = cmb->device_disconnect_time;
 981                 break;
 982         case cmb_control_unit_queuing_time:
 983                 val = cmb->control_unit_queuing_time;
 984                 break;
 985         case cmb_device_active_only_time:
 986                 val = cmb->device_active_only_time;
 987                 break;
 988         case cmb_device_busy_time:
 989                 val = cmb->device_busy_time;
 990                 break;
 991         case cmb_initial_command_response_time:
 992                 val = cmb->initial_command_response_time;
 993                 break;
 994         default:
 995                 ret = 0;
 996                 goto out;
 997         }
 998         ret = time_to_avg_nsec(val, cmb->sample_count);
 999 out:
1000         spin_unlock_irqrestore(cdev->ccwlock, flags);
1001         return ret;
1002 }
1003
1004 static int readall_cmbe(struct ccw_device *cdev, struct cmbdata *data)
1005 {
1006         struct cmbe *cmb;
1007         struct cmb_data *cmb_data;
1008         u64 time;
1009         unsigned long flags;
1010         int ret;
1011
1012         ret = cmf_cmb_copy_wait(cdev);
1013         if (ret < 0)
1014                 return ret;
1015         spin_lock_irqsave(cdev->ccwlock, flags);
1016         cmb_data = cdev->private->cmb;
1017         if (!cmb_data) {
1018                 ret = -ENODEV;
1019                 goto out;
1020         }
1021         if (cmb_data->last_update == 0) {
1022                 ret = -EAGAIN;
1023                 goto out;
1024         }
1025         time = cmb_data->last_update - cdev->private->cmb_start_time;
1026
1027         memset (data, 0, sizeof(struct cmbdata));
1028
1029         /* we only know values before device_busy_time */
1030         data->size = offsetof(struct cmbdata, device_busy_time);
1031
1032         /* conver to nanoseconds */
1033         data->elapsed_time = (time * 1000) >> 12;
1034
1035         cmb = cmb_data->last_block;
1036         /* copy data to new structure */
1037         data->ssch_rsch_count = cmb->ssch_rsch_count;
1038         data->sample_count = cmb->sample_count;
1039
1040         /* time fields are converted to nanoseconds while copying */
1041         data->device_connect_time = time_to_nsec(cmb->device_connect_time);
1042         data->function_pending_time = time_to_nsec(cmb->function_pending_time);
1043         data->device_disconnect_time =
1044                 time_to_nsec(cmb->device_disconnect_time);
1045         data->control_unit_queuing_time
1046                 = time_to_nsec(cmb->control_unit_queuing_time);
1047         data->device_active_only_time
1048                 = time_to_nsec(cmb->device_active_only_time);
1049         data->device_busy_time = time_to_nsec(cmb->device_busy_time);
1050         data->initial_command_response_time
1051                 = time_to_nsec(cmb->initial_command_response_time);
1052
1053         ret = 0;
1054 out:
1055         spin_unlock_irqrestore(cdev->ccwlock, flags);
1056         return ret;
1057 }
1058
1059 static void reset_cmbe(struct ccw_device *cdev)
1060 {
1061         cmf_generic_reset(cdev);
1062 }
1063
1064 static void * align_cmbe(void *area)
1065 {
1066         return cmbe_align(area);
1067 }
1068
1069 static struct attribute_group cmf_attr_group_ext;
1070
1071 static struct cmb_operations cmbops_extended = {
1072         .alloc      = alloc_cmbe,
1073         .free       = free_cmbe,
1074         .set        = set_cmbe,
1075         .read       = read_cmbe,
1076         .readall    = readall_cmbe,
1077         .reset      = reset_cmbe,
1078         .align      = align_cmbe,
1079         .attr_group = &cmf_attr_group_ext,
1080 };
1081
1082 static ssize_t cmb_show_attr(struct device *dev, char *buf, enum cmb_index idx)
1083 {
1084         return sprintf(buf, "%lld\n",
1085                 (unsigned long long) cmf_read(to_ccwdev(dev), idx));
1086 }
1087
1088 static ssize_t cmb_show_avg_sample_interval(struct device *dev,
1089                                             struct device_attribute *attr,
1090                                             char *buf)
1091 {
1092         struct ccw_device *cdev;
1093         long interval;
1094         unsigned long count;
1095         struct cmb_data *cmb_data;
1096
1097         cdev = to_ccwdev(dev);
1098         count = cmf_read(cdev, cmb_sample_count);
1099         spin_lock_irq(cdev->ccwlock);
1100         cmb_data = cdev->private->cmb;
1101         if (count) {
1102                 interval = cmb_data->last_update -
1103                         cdev->private->cmb_start_time;
1104                 interval = (interval * 1000) >> 12;
1105                 interval /= count;
1106         } else
1107                 interval = -1;
1108         spin_unlock_irq(cdev->ccwlock);
1109         return sprintf(buf, "%ld\n", interval);
1110 }
1111
1112 static ssize_t cmb_show_avg_utilization(struct device *dev,
1113                                         struct device_attribute *attr,
1114                                         char *buf)
1115 {
1116         struct cmbdata data;
1117         u64 utilization;
1118         unsigned long t, u;
1119         int ret;
1120
1121         ret = cmf_readall(to_ccwdev(dev), &data);
1122         if (ret == -EAGAIN || ret == -ENODEV)
1123                 /* No data (yet/currently) available to use for calculation. */
1124                 return sprintf(buf, "n/a\n");
1125         else if (ret)
1126                 return ret;
1127
1128         utilization = data.device_connect_time +
1129                       data.function_pending_time +
1130                       data.device_disconnect_time;
1131
1132         /* shift to avoid long long division */
1133         while (-1ul < (data.elapsed_time | utilization)) {
1134                 utilization >>= 8;
1135                 data.elapsed_time >>= 8;
1136         }
1137
1138         /* calculate value in 0.1 percent units */
1139         t = (unsigned long) data.elapsed_time / 1000;
1140         u = (unsigned long) utilization / t;
1141
1142         return sprintf(buf, "%02ld.%01ld%%\n", u/ 10, u - (u/ 10) * 10);
1143 }
1144
1145 #define cmf_attr(name) \
1146 static ssize_t show_##name(struct device *dev, \
1147                            struct device_attribute *attr, char *buf)    \
1148 { return cmb_show_attr((dev), buf, cmb_##name); } \
1149 static DEVICE_ATTR(name, 0444, show_##name, NULL);
1150
1151 #define cmf_attr_avg(name) \
1152 static ssize_t show_avg_##name(struct device *dev, \
1153                                struct device_attribute *attr, char *buf) \
1154 { return cmb_show_attr((dev), buf, cmb_##name); } \
1155 static DEVICE_ATTR(avg_##name, 0444, show_avg_##name, NULL);
1156
1157 cmf_attr(ssch_rsch_count);
1158 cmf_attr(sample_count);
1159 cmf_attr_avg(device_connect_time);
1160 cmf_attr_avg(function_pending_time);
1161 cmf_attr_avg(device_disconnect_time);
1162 cmf_attr_avg(control_unit_queuing_time);
1163 cmf_attr_avg(device_active_only_time);
1164 cmf_attr_avg(device_busy_time);
1165 cmf_attr_avg(initial_command_response_time);
1166
1167 static DEVICE_ATTR(avg_sample_interval, 0444, cmb_show_avg_sample_interval,
1168                    NULL);
1169 static DEVICE_ATTR(avg_utilization, 0444, cmb_show_avg_utilization, NULL);
1170
1171 static struct attribute *cmf_attributes[] = {
1172         &dev_attr_avg_sample_interval.attr,
1173         &dev_attr_avg_utilization.attr,
1174         &dev_attr_ssch_rsch_count.attr,
1175         &dev_attr_sample_count.attr,
1176         &dev_attr_avg_device_connect_time.attr,
1177         &dev_attr_avg_function_pending_time.attr,
1178         &dev_attr_avg_device_disconnect_time.attr,
1179         &dev_attr_avg_control_unit_queuing_time.attr,
1180         &dev_attr_avg_device_active_only_time.attr,
1181         NULL,
1182 };
1183
1184 static struct attribute_group cmf_attr_group = {
1185         .name  = "cmf",
1186         .attrs = cmf_attributes,
1187 };
1188
1189 static struct attribute *cmf_attributes_ext[] = {
1190         &dev_attr_avg_sample_interval.attr,
1191         &dev_attr_avg_utilization.attr,
1192         &dev_attr_ssch_rsch_count.attr,
1193         &dev_attr_sample_count.attr,
1194         &dev_attr_avg_device_connect_time.attr,
1195         &dev_attr_avg_function_pending_time.attr,
1196         &dev_attr_avg_device_disconnect_time.attr,
1197         &dev_attr_avg_control_unit_queuing_time.attr,
1198         &dev_attr_avg_device_active_only_time.attr,
1199         &dev_attr_avg_device_busy_time.attr,
1200         &dev_attr_avg_initial_command_response_time.attr,
1201         NULL,
1202 };
1203
1204 static struct attribute_group cmf_attr_group_ext = {
1205         .name  = "cmf",
1206         .attrs = cmf_attributes_ext,
1207 };
1208
1209 static ssize_t cmb_enable_show(struct device *dev,
1210                                struct device_attribute *attr,
1211                                char *buf)
1212 {
1213         return sprintf(buf, "%d\n", to_ccwdev(dev)->private->cmb ? 1 : 0);
1214 }
1215
1216 static ssize_t cmb_enable_store(struct device *dev,
1217                                 struct device_attribute *attr, const char *buf,
1218                                 size_t c)
1219 {
1220         struct ccw_device *cdev;
1221         int ret;
1222
1223         cdev = to_ccwdev(dev);
1224
1225         switch (buf[0]) {
1226         case '0':
1227                 ret = disable_cmf(cdev);
1228                 if (ret)
1229                         dev_info(&cdev->dev, "disable_cmf failed (%d)\n", ret);
1230                 break;
1231         case '1':
1232                 ret = enable_cmf(cdev);
1233                 if (ret && ret != -EBUSY)
1234                         dev_info(&cdev->dev, "enable_cmf failed (%d)\n", ret);
1235                 break;
1236         }
1237
1238         return c;
1239 }
1240
1241 DEVICE_ATTR(cmb_enable, 0644, cmb_enable_show, cmb_enable_store);
1242
1243 /**
1244  * enable_cmf() - switch on the channel measurement for a specific device
1245  *  @cdev:      The ccw device to be enabled
1246  *
1247  *  Returns %0 for success or a negative error value.
1248  *
1249  *  Context:
1250  *    non-atomic
1251  */
1252 int enable_cmf(struct ccw_device *cdev)
1253 {
1254         int ret;
1255
1256         ret = cmbops->alloc(cdev);
1257         cmbops->reset(cdev);
1258         if (ret)
1259                 return ret;
1260         ret = cmbops->set(cdev, 2);
1261         if (ret) {
1262                 cmbops->free(cdev);
1263                 return ret;
1264         }
1265         ret = sysfs_create_group(&cdev->dev.kobj, cmbops->attr_group);
1266         if (!ret)
1267                 return 0;
1268         cmbops->set(cdev, 0);  //FIXME: this can fail
1269         cmbops->free(cdev);
1270         return ret;
1271 }
1272
1273 /**
1274  * disable_cmf() - switch off the channel measurement for a specific device
1275  *  @cdev:      The ccw device to be disabled
1276  *
1277  *  Returns %0 for success or a negative error value.
1278  *
1279  *  Context:
1280  *    non-atomic
1281  */
1282 int disable_cmf(struct ccw_device *cdev)
1283 {
1284         int ret;
1285
1286         ret = cmbops->set(cdev, 0);
1287         if (ret)
1288                 return ret;
1289         cmbops->free(cdev);
1290         sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);
1291         return ret;
1292 }
1293
1294 /**
1295  * cmf_read() - read one value from the current channel measurement block
1296  * @cdev:       the channel to be read
1297  * @index:      the index of the value to be read
1298  *
1299  * Returns the value read or %0 if the value cannot be read.
1300  *
1301  *  Context:
1302  *    any
1303  */
1304 u64 cmf_read(struct ccw_device *cdev, int index)
1305 {
1306         return cmbops->read(cdev, index);
1307 }
1308
1309 /**
1310  * cmf_readall() - read the current channel measurement block
1311  * @cdev:       the channel to be read
1312  * @data:       a pointer to a data block that will be filled
1313  *
1314  * Returns %0 on success, a negative error value otherwise.
1315  *
1316  *  Context:
1317  *    any
1318  */
1319 int cmf_readall(struct ccw_device *cdev, struct cmbdata *data)
1320 {
1321         return cmbops->readall(cdev, data);
1322 }
1323
1324 /* Reenable cmf when a disconnected device becomes available again. */
1325 int cmf_reenable(struct ccw_device *cdev)
1326 {
1327         cmbops->reset(cdev);
1328         return cmbops->set(cdev, 2);
1329 }
1330
1331 static int __init init_cmf(void)
1332 {
1333         char *format_string;
1334         char *detect_string = "parameter";
1335
1336         /*
1337          * If the user did not give a parameter, see if we are running on a
1338          * machine supporting extended measurement blocks, otherwise fall back
1339          * to basic mode.
1340          */
1341         if (format == CMF_AUTODETECT) {
1342                 if (!css_characteristics_avail ||
1343                     !css_general_characteristics.ext_mb) {
1344                         format = CMF_BASIC;
1345                 } else {
1346                         format = CMF_EXTENDED;
1347                 }
1348                 detect_string = "autodetected";
1349         } else {
1350                 detect_string = "parameter";
1351         }
1352
1353         switch (format) {
1354         case CMF_BASIC:
1355                 format_string = "basic";
1356                 cmbops = &cmbops_basic;
1357                 break;
1358         case CMF_EXTENDED:
1359                 format_string = "extended";
1360                 cmbops = &cmbops_extended;
1361                 break;
1362         default:
1363                 printk(KERN_ERR "cio: Invalid format %d for channel "
1364                         "measurement facility\n", format);
1365                 return 1;
1366         }
1367
1368         printk(KERN_INFO "cio: Channel measurement facility using %s "
1369                "format (%s)\n", format_string, detect_string);
1370         return 0;
1371 }
1372
1373 module_init(init_cmf);
1374
1375
1376 MODULE_AUTHOR("Arnd Bergmann <arndb@de.ibm.com>");
1377 MODULE_LICENSE("GPL");
1378 MODULE_DESCRIPTION("channel measurement facility base driver\n"
1379                    "Copyright 2003 IBM Corporation\n");
1380
1381 EXPORT_SYMBOL_GPL(enable_cmf);
1382 EXPORT_SYMBOL_GPL(disable_cmf);
1383 EXPORT_SYMBOL_GPL(cmf_read);
1384 EXPORT_SYMBOL_GPL(cmf_readall);