git.oblomov.eu Git - linux-2.6/blob - drivers/s390/crypto/ap_bus.c

   1 /*
   2  * linux/drivers/s390/crypto/ap_bus.c
   3  *
   4  * Copyright (C) 2006 IBM Corporation
   5  * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
   6  *            Martin Schwidefsky <schwidefsky@de.ibm.com>
   7  *            Ralph Wuerthner <rwuerthn@de.ibm.com>
   8  *            Felix Beck <felix.beck@de.ibm.com>
   9  *
  10  * Adjunct processor bus.
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2, or (at your option)
  15  * any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  25  */
  26
  27 #define KMSG_COMPONENT "ap"
  28 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  29
  30 #include <linux/module.h>
  31 #include <linux/init.h>
  32 #include <linux/delay.h>
  33 #include <linux/err.h>
  34 #include <linux/interrupt.h>
  35 #include <linux/workqueue.h>
  36 #include <linux/notifier.h>
  37 #include <linux/kthread.h>
  38 #include <linux/mutex.h>
  39 #include <asm/s390_rdev.h>
  40 #include <asm/reset.h>
  41 #include <asm/airq.h>
  42 #include <asm/atomic.h>
  43 #include <asm/system.h>
  44 #include <asm/isc.h>
  45 #include <linux/hrtimer.h>
  46 #include <linux/ktime.h>
  47
  48 #include "ap_bus.h"
  49
  50 /* Some prototypes. */
  51 static void ap_scan_bus(struct work_struct *);
  52 static void ap_poll_all(unsigned long);
  53 static enum hrtimer_restart ap_poll_timeout(struct hrtimer *);
  54 static int ap_poll_thread_start(void);
  55 static void ap_poll_thread_stop(void);
  56 static void ap_request_timeout(unsigned long);
  57 static inline void ap_schedule_poll_timer(void);
  58
  59 /*
  60  * Module description.
  61  */
  62 MODULE_AUTHOR("IBM Corporation");
  63 MODULE_DESCRIPTION("Adjunct Processor Bus driver, "
  64                    "Copyright 2006 IBM Corporation");
  65 MODULE_LICENSE("GPL");
  66
  67 /*
  68  * Module parameter
  69  */
  70 int ap_domain_index = -1;       /* Adjunct Processor Domain Index */
  71 module_param_named(domain, ap_domain_index, int, 0000);
  72 MODULE_PARM_DESC(domain, "domain index for ap devices");
  73 EXPORT_SYMBOL(ap_domain_index);
  74
  75 static int ap_thread_flag = 0;
  76 module_param_named(poll_thread, ap_thread_flag, int, 0000);
  77 MODULE_PARM_DESC(poll_thread, "Turn on/off poll thread, default is 0 (off).");
  78
  79 static struct device *ap_root_device = NULL;
  80 static DEFINE_SPINLOCK(ap_device_list_lock);
  81 static LIST_HEAD(ap_device_list);
  82
  83 /*
  84  * Workqueue & timer for bus rescan.
  85  */
  86 static struct workqueue_struct *ap_work_queue;
  87 static struct timer_list ap_config_timer;
  88 static int ap_config_time = AP_CONFIG_TIME;
  89 static DECLARE_WORK(ap_config_work, ap_scan_bus);
  90
  91 /*
  92  * Tasklet & timer for AP request polling and interrupts
  93  */
  94 static DECLARE_TASKLET(ap_tasklet, ap_poll_all, 0);
  95 static atomic_t ap_poll_requests = ATOMIC_INIT(0);
  96 static DECLARE_WAIT_QUEUE_HEAD(ap_poll_wait);
  97 static struct task_struct *ap_poll_kthread = NULL;
  98 static DEFINE_MUTEX(ap_poll_thread_mutex);
  99 static void *ap_interrupt_indicator;
 100 static struct hrtimer ap_poll_timer;
 101 /* In LPAR poll with 4kHz frequency. Poll every 250000 nanoseconds.
 102  * If z/VM change to 1500000 nanoseconds to adjust to z/VM polling.*/
 103 static unsigned long long poll_timeout = 250000;
 104
 105 /**
 106  * ap_using_interrupts() - Returns non-zero if interrupt support is
 107  * available.
 108  */
 109 static inline int ap_using_interrupts(void)
 110 {
 111         return ap_interrupt_indicator != NULL;
 112 }
 113
 114 /**
 115  * ap_intructions_available() - Test if AP instructions are available.
 116  *
 117  * Returns 0 if the AP instructions are installed.
 118  */
 119 static inline int ap_instructions_available(void)
 120 {
 121         register unsigned long reg0 asm ("0") = AP_MKQID(0,0);
 122         register unsigned long reg1 asm ("1") = -ENODEV;
 123         register unsigned long reg2 asm ("2") = 0UL;
 124
 125         asm volatile(
 126                 "   .long 0xb2af0000\n"         /* PQAP(TAPQ) */
 127                 "0: la    %1,0\n"
 128                 "1:\n"
 129                 EX_TABLE(0b, 1b)
 130                 : "+d" (reg0), "+d" (reg1), "+d" (reg2) : : "cc" );
 131         return reg1;
 132 }
 133
 134 /**
 135  * ap_interrupts_available(): Test if AP interrupts are available.
 136  *
 137  * Returns 1 if AP interrupts are available.
 138  */
 139 static int ap_interrupts_available(void)
 140 {
 141         unsigned long long facility_bits[2];
 142
 143         if (stfle(facility_bits, 2) <= 1)
 144                 return 0;
 145         if (!(facility_bits[0] & (1ULL << 61)) ||
 146             !(facility_bits[1] & (1ULL << 62)))
 147                 return 0;
 148         return 1;
 149 }
 150
 151 /**
 152  * ap_test_queue(): Test adjunct processor queue.
 153  * @qid: The AP queue number
 154  * @queue_depth: Pointer to queue depth value
 155  * @device_type: Pointer to device type value
 156  *
 157  * Returns AP queue status structure.
 158  */
 159 static inline struct ap_queue_status
 160 ap_test_queue(ap_qid_t qid, int *queue_depth, int *device_type)
 161 {
 162         register unsigned long reg0 asm ("0") = qid;
 163         register struct ap_queue_status reg1 asm ("1");
 164         register unsigned long reg2 asm ("2") = 0UL;
 165
 166         asm volatile(".long 0xb2af0000"         /* PQAP(TAPQ) */
 167                      : "+d" (reg0), "=d" (reg1), "+d" (reg2) : : "cc");
 168         *device_type = (int) (reg2 >> 24);
 169         *queue_depth = (int) (reg2 & 0xff);
 170         return reg1;
 171 }
 172
 173 /**
 174  * ap_reset_queue(): Reset adjunct processor queue.
 175  * @qid: The AP queue number
 176  *
 177  * Returns AP queue status structure.
 178  */
 179 static inline struct ap_queue_status ap_reset_queue(ap_qid_t qid)
 180 {
 181         register unsigned long reg0 asm ("0") = qid | 0x01000000UL;
 182         register struct ap_queue_status reg1 asm ("1");
 183         register unsigned long reg2 asm ("2") = 0UL;
 184
 185         asm volatile(
 186                 ".long 0xb2af0000"              /* PQAP(RAPQ) */
 187                 : "+d" (reg0), "=d" (reg1), "+d" (reg2) : : "cc");
 188         return reg1;
 189 }
 190
 191 #ifdef CONFIG_64BIT
 192 /**
 193  * ap_queue_interruption_control(): Enable interruption for a specific AP.
 194  * @qid: The AP queue number
 195  * @ind: The notification indicator byte
 196  *
 197  * Returns AP queue status.
 198  */
 199 static inline struct ap_queue_status
 200 ap_queue_interruption_control(ap_qid_t qid, void *ind)
 201 {
 202         register unsigned long reg0 asm ("0") = qid | 0x03000000UL;
 203         register unsigned long reg1_in asm ("1") = 0x0000800000000000UL | AP_ISC;
 204         register struct ap_queue_status reg1_out asm ("1");
 205         register void *reg2 asm ("2") = ind;
 206         asm volatile(
 207                 ".long 0xb2af0000"              /* PQAP(RAPQ) */
 208                 : "+d" (reg0), "+d" (reg1_in), "=d" (reg1_out), "+d" (reg2)
 209                 :
 210                 : "cc" );
 211         return reg1_out;
 212 }
 213 #endif
 214
 215 /**
 216  * ap_queue_enable_interruption(): Enable interruption on an AP.
 217  * @qid: The AP queue number
 218  * @ind: the notification indicator byte
 219  *
 220  * Enables interruption on AP queue via ap_queue_interruption_control(). Based
 221  * on the return value it waits a while and tests the AP queue if interrupts
 222  * have been switched on using ap_test_queue().
 223  */
 224 static int ap_queue_enable_interruption(ap_qid_t qid, void *ind)
 225 {
 226 #ifdef CONFIG_64BIT
 227         struct ap_queue_status status;
 228         int t_depth, t_device_type, rc, i;
 229
 230         rc = -EBUSY;
 231         status = ap_queue_interruption_control(qid, ind);
 232
 233         for (i = 0; i < AP_MAX_RESET; i++) {
 234                 switch (status.response_code) {
 235                 case AP_RESPONSE_NORMAL:
 236                         if (status.int_enabled)
 237                                 return 0;
 238                         break;
 239                 case AP_RESPONSE_RESET_IN_PROGRESS:
 240                 case AP_RESPONSE_BUSY:
 241                         break;
 242                 case AP_RESPONSE_Q_NOT_AVAIL:
 243                 case AP_RESPONSE_DECONFIGURED:
 244                 case AP_RESPONSE_CHECKSTOPPED:
 245                 case AP_RESPONSE_INVALID_ADDRESS:
 246                         return -ENODEV;
 247                 case AP_RESPONSE_OTHERWISE_CHANGED:
 248                         if (status.int_enabled)
 249                                 return 0;
 250                         break;
 251                 default:
 252                         break;
 253                 }
 254                 if (i < AP_MAX_RESET - 1) {
 255                         udelay(5);
 256                         status = ap_test_queue(qid, &t_depth, &t_device_type);
 257                 }
 258         }
 259         return rc;
 260 #else
 261         return -EINVAL;
 262 #endif
 263 }
 264
 265 /**
 266  * __ap_send(): Send message to adjunct processor queue.
 267  * @qid: The AP queue number
 268  * @psmid: The program supplied message identifier
 269  * @msg: The message text
 270  * @length: The message length
 271  *
 272  * Returns AP queue status structure.
 273  * Condition code 1 on NQAP can't happen because the L bit is 1.
 274  * Condition code 2 on NQAP also means the send is incomplete,
 275  * because a segment boundary was reached. The NQAP is repeated.
 276  */
 277 static inline struct ap_queue_status
 278 __ap_send(ap_qid_t qid, unsigned long long psmid, void *msg, size_t length)
 279 {
 280         typedef struct { char _[length]; } msgblock;
 281         register unsigned long reg0 asm ("0") = qid | 0x40000000UL;
 282         register struct ap_queue_status reg1 asm ("1");
 283         register unsigned long reg2 asm ("2") = (unsigned long) msg;
 284         register unsigned long reg3 asm ("3") = (unsigned long) length;
 285         register unsigned long reg4 asm ("4") = (unsigned int) (psmid >> 32);
 286         register unsigned long reg5 asm ("5") = (unsigned int) psmid;
 287
 288         asm volatile (
 289                 "0: .long 0xb2ad0042\n"         /* DQAP */
 290                 "   brc   2,0b"
 291                 : "+d" (reg0), "=d" (reg1), "+d" (reg2), "+d" (reg3)
 292                 : "d" (reg4), "d" (reg5), "m" (*(msgblock *) msg)
 293                 : "cc" );
 294         return reg1;
 295 }
 296
 297 int ap_send(ap_qid_t qid, unsigned long long psmid, void *msg, size_t length)
 298 {
 299         struct ap_queue_status status;
 300
 301         status = __ap_send(qid, psmid, msg, length);
 302         switch (status.response_code) {
 303         case AP_RESPONSE_NORMAL:
 304                 return 0;
 305         case AP_RESPONSE_Q_FULL:
 306         case AP_RESPONSE_RESET_IN_PROGRESS:
 307                 return -EBUSY;
 308         default:        /* Device is gone. */
 309                 return -ENODEV;
 310         }
 311 }
 312 EXPORT_SYMBOL(ap_send);
 313
 314 /**
 315  * __ap_recv(): Receive message from adjunct processor queue.
 316  * @qid: The AP queue number
 317  * @psmid: Pointer to program supplied message identifier
 318  * @msg: The message text
 319  * @length: The message length
 320  *
 321  * Returns AP queue status structure.
 322  * Condition code 1 on DQAP means the receive has taken place
 323  * but only partially.  The response is incomplete, hence the
 324  * DQAP is repeated.
 325  * Condition code 2 on DQAP also means the receive is incomplete,
 326  * this time because a segment boundary was reached. Again, the
 327  * DQAP is repeated.
 328  * Note that gpr2 is used by the DQAP instruction to keep track of
 329  * any 'residual' length, in case the instruction gets interrupted.
 330  * Hence it gets zeroed before the instruction.
 331  */
 332 static inline struct ap_queue_status
 333 __ap_recv(ap_qid_t qid, unsigned long long *psmid, void *msg, size_t length)
 334 {
 335         typedef struct { char _[length]; } msgblock;
 336         register unsigned long reg0 asm("0") = qid | 0x80000000UL;
 337         register struct ap_queue_status reg1 asm ("1");
 338         register unsigned long reg2 asm("2") = 0UL;
 339         register unsigned long reg4 asm("4") = (unsigned long) msg;
 340         register unsigned long reg5 asm("5") = (unsigned long) length;
 341         register unsigned long reg6 asm("6") = 0UL;
 342         register unsigned long reg7 asm("7") = 0UL;
 343
 344
 345         asm volatile(
 346                 "0: .long 0xb2ae0064\n"
 347                 "   brc   6,0b\n"
 348                 : "+d" (reg0), "=d" (reg1), "+d" (reg2),
 349                 "+d" (reg4), "+d" (reg5), "+d" (reg6), "+d" (reg7),
 350                 "=m" (*(msgblock *) msg) : : "cc" );
 351         *psmid = (((unsigned long long) reg6) << 32) + reg7;
 352         return reg1;
 353 }
 354
 355 int ap_recv(ap_qid_t qid, unsigned long long *psmid, void *msg, size_t length)
 356 {
 357         struct ap_queue_status status;
 358
 359         status = __ap_recv(qid, psmid, msg, length);
 360         switch (status.response_code) {
 361         case AP_RESPONSE_NORMAL:
 362                 return 0;
 363         case AP_RESPONSE_NO_PENDING_REPLY:
 364                 if (status.queue_empty)
 365                         return -ENOENT;
 366                 return -EBUSY;
 367         case AP_RESPONSE_RESET_IN_PROGRESS:
 368                 return -EBUSY;
 369         default:
 370                 return -ENODEV;
 371         }
 372 }
 373 EXPORT_SYMBOL(ap_recv);
 374
 375 /**
 376  * ap_query_queue(): Check if an AP queue is available.
 377  * @qid: The AP queue number
 378  * @queue_depth: Pointer to queue depth value
 379  * @device_type: Pointer to device type value
 380  *
 381  * The test is repeated for AP_MAX_RESET times.
 382  */
 383 static int ap_query_queue(ap_qid_t qid, int *queue_depth, int *device_type)
 384 {
 385         struct ap_queue_status status;
 386         int t_depth, t_device_type, rc, i;
 387
 388         rc = -EBUSY;
 389         for (i = 0; i < AP_MAX_RESET; i++) {
 390                 status = ap_test_queue(qid, &t_depth, &t_device_type);
 391                 switch (status.response_code) {
 392                 case AP_RESPONSE_NORMAL:
 393                         *queue_depth = t_depth + 1;
 394                         *device_type = t_device_type;
 395                         rc = 0;
 396                         break;
 397                 case AP_RESPONSE_Q_NOT_AVAIL:
 398                         rc = -ENODEV;
 399                         break;
 400                 case AP_RESPONSE_RESET_IN_PROGRESS:
 401                         break;
 402                 case AP_RESPONSE_DECONFIGURED:
 403                         rc = -ENODEV;
 404                         break;
 405                 case AP_RESPONSE_CHECKSTOPPED:
 406                         rc = -ENODEV;
 407                         break;
 408                 case AP_RESPONSE_INVALID_ADDRESS:
 409                         rc = -ENODEV;
 410                         break;
 411                 case AP_RESPONSE_OTHERWISE_CHANGED:
 412                         break;
 413                 case AP_RESPONSE_BUSY:
 414                         break;
 415                 default:
 416                         BUG();
 417                 }
 418                 if (rc != -EBUSY)
 419                         break;
 420                 if (i < AP_MAX_RESET - 1)
 421                         udelay(5);
 422         }
 423         return rc;
 424 }
 425
 426 /**
 427  * ap_init_queue(): Reset an AP queue.
 428  * @qid: The AP queue number
 429  *
 430  * Reset an AP queue and wait for it to become available again.
 431  */
 432 static int ap_init_queue(ap_qid_t qid)
 433 {
 434         struct ap_queue_status status;
 435         int rc, dummy, i;
 436
 437         rc = -ENODEV;
 438         status = ap_reset_queue(qid);
 439         for (i = 0; i < AP_MAX_RESET; i++) {
 440                 switch (status.response_code) {
 441                 case AP_RESPONSE_NORMAL:
 442                         if (status.queue_empty)
 443                                 rc = 0;
 444                         break;
 445                 case AP_RESPONSE_Q_NOT_AVAIL:
 446                 case AP_RESPONSE_DECONFIGURED:
 447                 case AP_RESPONSE_CHECKSTOPPED:
 448                         i = AP_MAX_RESET;       /* return with -ENODEV */
 449                         break;
 450                 case AP_RESPONSE_RESET_IN_PROGRESS:
 451                         rc = -EBUSY;
 452                 case AP_RESPONSE_BUSY:
 453                 default:
 454                         break;
 455                 }
 456                 if (rc != -ENODEV && rc != -EBUSY)
 457                         break;
 458                 if (i < AP_MAX_RESET - 1) {
 459                         udelay(5);
 460                         status = ap_test_queue(qid, &dummy, &dummy);
 461                 }
 462         }
 463         if (rc == 0 && ap_using_interrupts()) {
 464                 rc = ap_queue_enable_interruption(qid, ap_interrupt_indicator);
 465                 /* If interruption mode is supported by the machine,
 466                 * but an AP can not be enabled for interruption then
 467                 * the AP will be discarded.    */
 468                 if (rc)
 469                         pr_err("Registering adapter interrupts for "
 470                                "AP %d failed\n", AP_QID_DEVICE(qid));
 471         }
 472         return rc;
 473 }
 474
 475 /**
 476  * ap_increase_queue_count(): Arm request timeout.
 477  * @ap_dev: Pointer to an AP device.
 478  *
 479  * Arm request timeout if an AP device was idle and a new request is submitted.
 480  */
 481 static void ap_increase_queue_count(struct ap_device *ap_dev)
 482 {
 483         int timeout = ap_dev->drv->request_timeout;
 484
 485         ap_dev->queue_count++;
 486         if (ap_dev->queue_count == 1) {
 487                 mod_timer(&ap_dev->timeout, jiffies + timeout);
 488                 ap_dev->reset = AP_RESET_ARMED;
 489         }
 490 }
 491
 492 /**
 493  * ap_decrease_queue_count(): Decrease queue count.
 494  * @ap_dev: Pointer to an AP device.
 495  *
 496  * If AP device is still alive, re-schedule request timeout if there are still
 497  * pending requests.
 498  */
 499 static void ap_decrease_queue_count(struct ap_device *ap_dev)
 500 {
 501         int timeout = ap_dev->drv->request_timeout;
 502
 503         ap_dev->queue_count--;
 504         if (ap_dev->queue_count > 0)
 505                 mod_timer(&ap_dev->timeout, jiffies + timeout);
 506         else
 507                 /*
 508                  * The timeout timer should to be disabled now - since
 509                  * del_timer_sync() is very expensive, we just tell via the
 510                  * reset flag to ignore the pending timeout timer.
 511                  */
 512                 ap_dev->reset = AP_RESET_IGNORE;
 513 }
 514
 515 /*
 516  * AP device related attributes.
 517  */
 518 static ssize_t ap_hwtype_show(struct device *dev,
 519                               struct device_attribute *attr, char *buf)
 520 {
 521         struct ap_device *ap_dev = to_ap_dev(dev);
 522         return snprintf(buf, PAGE_SIZE, "%d\n", ap_dev->device_type);
 523 }
 524
 525 static DEVICE_ATTR(hwtype, 0444, ap_hwtype_show, NULL);
 526 static ssize_t ap_depth_show(struct device *dev, struct device_attribute *attr,
 527                              char *buf)
 528 {
 529         struct ap_device *ap_dev = to_ap_dev(dev);
 530         return snprintf(buf, PAGE_SIZE, "%d\n", ap_dev->queue_depth);
 531 }
 532
 533 static DEVICE_ATTR(depth, 0444, ap_depth_show, NULL);
 534 static ssize_t ap_request_count_show(struct device *dev,
 535                                      struct device_attribute *attr,
 536                                      char *buf)
 537 {
 538         struct ap_device *ap_dev = to_ap_dev(dev);
 539         int rc;
 540
 541         spin_lock_bh(&ap_dev->lock);
 542         rc = snprintf(buf, PAGE_SIZE, "%d\n", ap_dev->total_request_count);
 543         spin_unlock_bh(&ap_dev->lock);
 544         return rc;
 545 }
 546
 547 static DEVICE_ATTR(request_count, 0444, ap_request_count_show, NULL);
 548
 549 static ssize_t ap_modalias_show(struct device *dev,
 550                                 struct device_attribute *attr, char *buf)
 551 {
 552         return sprintf(buf, "ap:t%02X", to_ap_dev(dev)->device_type);
 553 }
 554
 555 static DEVICE_ATTR(modalias, 0444, ap_modalias_show, NULL);
 556
 557 static struct attribute *ap_dev_attrs[] = {
 558         &dev_attr_hwtype.attr,
 559         &dev_attr_depth.attr,
 560         &dev_attr_request_count.attr,
 561         &dev_attr_modalias.attr,
 562         NULL
 563 };
 564 static struct attribute_group ap_dev_attr_group = {
 565         .attrs = ap_dev_attrs
 566 };
 567
 568 /**
 569  * ap_bus_match()
 570  * @dev: Pointer to device
 571  * @drv: Pointer to device_driver
 572  *
 573  * AP bus driver registration/unregistration.
 574  */
 575 static int ap_bus_match(struct device *dev, struct device_driver *drv)
 576 {
 577         struct ap_device *ap_dev = to_ap_dev(dev);
 578         struct ap_driver *ap_drv = to_ap_drv(drv);
 579         struct ap_device_id *id;
 580
 581         /*
 582          * Compare device type of the device with the list of
 583          * supported types of the device_driver.
 584          */
 585         for (id = ap_drv->ids; id->match_flags; id++) {
 586                 if ((id->match_flags & AP_DEVICE_ID_MATCH_DEVICE_TYPE) &&
 587                     (id->dev_type != ap_dev->device_type))
 588                         continue;
 589                 return 1;
 590         }
 591         return 0;
 592 }
 593
 594 /**
 595  * ap_uevent(): Uevent function for AP devices.
 596  * @dev: Pointer to device
 597  * @env: Pointer to kobj_uevent_env
 598  *
 599  * It sets up a single environment variable DEV_TYPE which contains the
 600  * hardware device type.
 601  */
 602 static int ap_uevent (struct device *dev, struct kobj_uevent_env *env)
 603 {
 604         struct ap_device *ap_dev = to_ap_dev(dev);
 605         int retval = 0;
 606
 607         if (!ap_dev)
 608                 return -ENODEV;
 609
 610         /* Set up DEV_TYPE environment variable. */
 611         retval = add_uevent_var(env, "DEV_TYPE=%04X", ap_dev->device_type);
 612         if (retval)
 613                 return retval;
 614
 615         /* Add MODALIAS= */
 616         retval = add_uevent_var(env, "MODALIAS=ap:t%02X", ap_dev->device_type);
 617
 618         return retval;
 619 }
 620
 621 static struct bus_type ap_bus_type = {
 622         .name = "ap",
 623         .match = &ap_bus_match,
 624         .uevent = &ap_uevent,
 625 };
 626
 627 static int ap_device_probe(struct device *dev)
 628 {
 629         struct ap_device *ap_dev = to_ap_dev(dev);
 630         struct ap_driver *ap_drv = to_ap_drv(dev->driver);
 631         int rc;
 632
 633         ap_dev->drv = ap_drv;
 634         rc = ap_drv->probe ? ap_drv->probe(ap_dev) : -ENODEV;
 635         if (!rc) {
 636                 spin_lock_bh(&ap_device_list_lock);
 637                 list_add(&ap_dev->list, &ap_device_list);
 638                 spin_unlock_bh(&ap_device_list_lock);
 639         }
 640         return rc;
 641 }
 642
 643 /**
 644  * __ap_flush_queue(): Flush requests.
 645  * @ap_dev: Pointer to the AP device
 646  *
 647  * Flush all requests from the request/pending queue of an AP device.
 648  */
 649 static void __ap_flush_queue(struct ap_device *ap_dev)
 650 {
 651         struct ap_message *ap_msg, *next;
 652
 653         list_for_each_entry_safe(ap_msg, next, &ap_dev->pendingq, list) {
 654                 list_del_init(&ap_msg->list);
 655                 ap_dev->pendingq_count--;
 656                 ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV));
 657         }
 658         list_for_each_entry_safe(ap_msg, next, &ap_dev->requestq, list) {
 659                 list_del_init(&ap_msg->list);
 660                 ap_dev->requestq_count--;
 661                 ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV));
 662         }
 663 }
 664
 665 void ap_flush_queue(struct ap_device *ap_dev)
 666 {
 667         spin_lock_bh(&ap_dev->lock);
 668         __ap_flush_queue(ap_dev);
 669         spin_unlock_bh(&ap_dev->lock);
 670 }
 671 EXPORT_SYMBOL(ap_flush_queue);
 672
 673 static int ap_device_remove(struct device *dev)
 674 {
 675         struct ap_device *ap_dev = to_ap_dev(dev);
 676         struct ap_driver *ap_drv = ap_dev->drv;
 677
 678         ap_flush_queue(ap_dev);
 679         del_timer_sync(&ap_dev->timeout);
 680         spin_lock_bh(&ap_device_list_lock);
 681         list_del_init(&ap_dev->list);
 682         spin_unlock_bh(&ap_device_list_lock);
 683         if (ap_drv->remove)
 684                 ap_drv->remove(ap_dev);
 685         spin_lock_bh(&ap_dev->lock);
 686         atomic_sub(ap_dev->queue_count, &ap_poll_requests);
 687         spin_unlock_bh(&ap_dev->lock);
 688         return 0;
 689 }
 690
 691 int ap_driver_register(struct ap_driver *ap_drv, struct module *owner,
 692                        char *name)
 693 {
 694         struct device_driver *drv = &ap_drv->driver;
 695
 696         drv->bus = &ap_bus_type;
 697         drv->probe = ap_device_probe;
 698         drv->remove = ap_device_remove;
 699         drv->owner = owner;
 700         drv->name = name;
 701         return driver_register(drv);
 702 }
 703 EXPORT_SYMBOL(ap_driver_register);
 704
 705 void ap_driver_unregister(struct ap_driver *ap_drv)
 706 {
 707         driver_unregister(&ap_drv->driver);
 708 }
 709 EXPORT_SYMBOL(ap_driver_unregister);
 710
 711 /*
 712  * AP bus attributes.
 713  */
 714 static ssize_t ap_domain_show(struct bus_type *bus, char *buf)
 715 {
 716         return snprintf(buf, PAGE_SIZE, "%d\n", ap_domain_index);
 717 }
 718
 719 static BUS_ATTR(ap_domain, 0444, ap_domain_show, NULL);
 720
 721 static ssize_t ap_config_time_show(struct bus_type *bus, char *buf)
 722 {
 723         return snprintf(buf, PAGE_SIZE, "%d\n", ap_config_time);
 724 }
 725
 726 static ssize_t ap_interrupts_show(struct bus_type *bus, char *buf)
 727 {
 728         return snprintf(buf, PAGE_SIZE, "%d\n",
 729                         ap_using_interrupts() ? 1 : 0);
 730 }
 731
 732 static BUS_ATTR(ap_interrupts, 0444, ap_interrupts_show, NULL);
 733
 734 static ssize_t ap_config_time_store(struct bus_type *bus,
 735                                     const char *buf, size_t count)
 736 {
 737         int time;
 738
 739         if (sscanf(buf, "%d\n", &time) != 1 || time < 5 || time > 120)
 740                 return -EINVAL;
 741         ap_config_time = time;
 742         if (!timer_pending(&ap_config_timer) ||
 743             !mod_timer(&ap_config_timer, jiffies + ap_config_time * HZ)) {
 744                 ap_config_timer.expires = jiffies + ap_config_time * HZ;
 745                 add_timer(&ap_config_timer);
 746         }
 747         return count;
 748 }
 749
 750 static BUS_ATTR(config_time, 0644, ap_config_time_show, ap_config_time_store);
 751
 752 static ssize_t ap_poll_thread_show(struct bus_type *bus, char *buf)
 753 {
 754         return snprintf(buf, PAGE_SIZE, "%d\n", ap_poll_kthread ? 1 : 0);
 755 }
 756
 757 static ssize_t ap_poll_thread_store(struct bus_type *bus,
 758                                     const char *buf, size_t count)
 759 {
 760         int flag, rc;
 761
 762         if (sscanf(buf, "%d\n", &flag) != 1)
 763                 return -EINVAL;
 764         if (flag) {
 765                 rc = ap_poll_thread_start();
 766                 if (rc)
 767                         return rc;
 768         }
 769         else
 770                 ap_poll_thread_stop();
 771         return count;
 772 }
 773
 774 static BUS_ATTR(poll_thread, 0644, ap_poll_thread_show, ap_poll_thread_store);
 775
 776 static ssize_t poll_timeout_show(struct bus_type *bus, char *buf)
 777 {
 778         return snprintf(buf, PAGE_SIZE, "%llu\n", poll_timeout);
 779 }
 780
 781 static ssize_t poll_timeout_store(struct bus_type *bus, const char *buf,
 782                                   size_t count)
 783 {
 784         unsigned long long time;
 785         ktime_t hr_time;
 786
 787         /* 120 seconds = maximum poll interval */
 788         if (sscanf(buf, "%llu\n", &time) != 1 || time < 1 ||
 789             time > 120000000000ULL)
 790                 return -EINVAL;
 791         poll_timeout = time;
 792         hr_time = ktime_set(0, poll_timeout);
 793
 794         if (!hrtimer_is_queued(&ap_poll_timer) ||
 795             !hrtimer_forward(&ap_poll_timer, hrtimer_get_expires(&ap_poll_timer), hr_time)) {
 796                 hrtimer_set_expires(&ap_poll_timer, hr_time);
 797                 hrtimer_start_expires(&ap_poll_timer, HRTIMER_MODE_ABS);
 798         }
 799         return count;
 800 }
 801
 802 static BUS_ATTR(poll_timeout, 0644, poll_timeout_show, poll_timeout_store);
 803
 804 static struct bus_attribute *const ap_bus_attrs[] = {
 805         &bus_attr_ap_domain,
 806         &bus_attr_config_time,
 807         &bus_attr_poll_thread,
 808         &bus_attr_ap_interrupts,
 809         &bus_attr_poll_timeout,
 810         NULL,
 811 };
 812
 813 /**
 814  * ap_select_domain(): Select an AP domain.
 815  *
 816  * Pick one of the 16 AP domains.
 817  */
 818 static int ap_select_domain(void)
 819 {
 820         int queue_depth, device_type, count, max_count, best_domain;
 821         int rc, i, j;
 822
 823         /*
 824          * We want to use a single domain. Either the one specified with
 825          * the "domain=" parameter or the domain with the maximum number
 826          * of devices.
 827          */
 828         if (ap_domain_index >= 0 && ap_domain_index < AP_DOMAINS)
 829                 /* Domain has already been selected. */
 830                 return 0;
 831         best_domain = -1;
 832         max_count = 0;
 833         for (i = 0; i < AP_DOMAINS; i++) {
 834                 count = 0;
 835                 for (j = 0; j < AP_DEVICES; j++) {
 836                         ap_qid_t qid = AP_MKQID(j, i);
 837                         rc = ap_query_queue(qid, &queue_depth, &device_type);
 838                         if (rc)
 839                                 continue;
 840                         count++;
 841                 }
 842                 if (count > max_count) {
 843                         max_count = count;
 844                         best_domain = i;
 845                 }
 846         }
 847         if (best_domain >= 0){
 848                 ap_domain_index = best_domain;
 849                 return 0;
 850         }
 851         return -ENODEV;
 852 }
 853
 854 /**
 855  * ap_probe_device_type(): Find the device type of an AP.
 856  * @ap_dev: pointer to the AP device.
 857  *
 858  * Find the device type if query queue returned a device type of 0.
 859  */
 860 static int ap_probe_device_type(struct ap_device *ap_dev)
 861 {
 862         static unsigned char msg[] = {
 863                 0x00,0x06,0x00,0x00,0x00,0x00,0x00,0x00,
 864                 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 865                 0x00,0x00,0x00,0x58,0x00,0x00,0x00,0x00,
 866                 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 867                 0x01,0x00,0x43,0x43,0x41,0x2d,0x41,0x50,
 868                 0x50,0x4c,0x20,0x20,0x20,0x01,0x01,0x01,
 869                 0x00,0x00,0x00,0x00,0x50,0x4b,0x00,0x00,
 870                 0x00,0x00,0x01,0x1c,0x00,0x00,0x00,0x00,
 871                 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 872                 0x00,0x00,0x05,0xb8,0x00,0x00,0x00,0x00,
 873                 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 874                 0x70,0x00,0x41,0x00,0x00,0x00,0x00,0x00,
 875                 0x00,0x00,0x54,0x32,0x01,0x00,0xa0,0x00,
 876                 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 877                 0x00,0x00,0x00,0x00,0xb8,0x05,0x00,0x00,
 878                 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 879                 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 880                 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 881                 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 882                 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 883                 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 884                 0x00,0x00,0x0a,0x00,0x00,0x00,0x00,0x00,
 885                 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 886                 0x00,0x00,0x00,0x00,0x00,0x00,0x08,0x00,
 887                 0x49,0x43,0x53,0x46,0x20,0x20,0x20,0x20,
 888                 0x50,0x4b,0x0a,0x00,0x50,0x4b,0x43,0x53,
 889                 0x2d,0x31,0x2e,0x32,0x37,0x00,0x11,0x22,
 890                 0x33,0x44,0x55,0x66,0x77,0x88,0x99,0x00,
 891                 0x11,0x22,0x33,0x44,0x55,0x66,0x77,0x88,
 892                 0x99,0x00,0x11,0x22,0x33,0x44,0x55,0x66,
 893                 0x77,0x88,0x99,0x00,0x11,0x22,0x33,0x44,
 894                 0x55,0x66,0x77,0x88,0x99,0x00,0x11,0x22,
 895                 0x33,0x44,0x55,0x66,0x77,0x88,0x99,0x00,
 896                 0x11,0x22,0x33,0x5d,0x00,0x5b,0x00,0x77,
 897                 0x88,0x1e,0x00,0x00,0x57,0x00,0x00,0x00,
 898                 0x00,0x04,0x00,0x00,0x4f,0x00,0x00,0x00,
 899                 0x03,0x02,0x00,0x00,0x40,0x01,0x00,0x01,
 900                 0xce,0x02,0x68,0x2d,0x5f,0xa9,0xde,0x0c,
 901                 0xf6,0xd2,0x7b,0x58,0x4b,0xf9,0x28,0x68,
 902                 0x3d,0xb4,0xf4,0xef,0x78,0xd5,0xbe,0x66,
 903                 0x63,0x42,0xef,0xf8,0xfd,0xa4,0xf8,0xb0,
 904                 0x8e,0x29,0xc2,0xc9,0x2e,0xd8,0x45,0xb8,
 905                 0x53,0x8c,0x6f,0x4e,0x72,0x8f,0x6c,0x04,
 906                 0x9c,0x88,0xfc,0x1e,0xc5,0x83,0x55,0x57,
 907                 0xf7,0xdd,0xfd,0x4f,0x11,0x36,0x95,0x5d,
 908         };
 909         struct ap_queue_status status;
 910         unsigned long long psmid;
 911         char *reply;
 912         int rc, i;
 913
 914         reply = (void *) get_zeroed_page(GFP_KERNEL);
 915         if (!reply) {
 916                 rc = -ENOMEM;
 917                 goto out;
 918         }
 919
 920         status = __ap_send(ap_dev->qid, 0x0102030405060708ULL,
 921                            msg, sizeof(msg));
 922         if (status.response_code != AP_RESPONSE_NORMAL) {
 923                 rc = -ENODEV;
 924                 goto out_free;
 925         }
 926
 927         /* Wait for the test message to complete. */
 928         for (i = 0; i < 6; i++) {
 929                 mdelay(300);
 930                 status = __ap_recv(ap_dev->qid, &psmid, reply, 4096);
 931                 if (status.response_code == AP_RESPONSE_NORMAL &&
 932                     psmid == 0x0102030405060708ULL)
 933                         break;
 934         }
 935         if (i < 6) {
 936                 /* Got an answer. */
 937                 if (reply[0] == 0x00 && reply[1] == 0x86)
 938                         ap_dev->device_type = AP_DEVICE_TYPE_PCICC;
 939                 else
 940                         ap_dev->device_type = AP_DEVICE_TYPE_PCICA;
 941                 rc = 0;
 942         } else
 943                 rc = -ENODEV;
 944
 945 out_free:
 946         free_page((unsigned long) reply);
 947 out:
 948         return rc;
 949 }
 950
 951 static void ap_interrupt_handler(void *unused1, void *unused2)
 952 {
 953         tasklet_schedule(&ap_tasklet);
 954 }
 955
 956 /**
 957  * __ap_scan_bus(): Scan the AP bus.
 958  * @dev: Pointer to device
 959  * @data: Pointer to data
 960  *
 961  * Scan the AP bus for new devices.
 962  */
 963 static int __ap_scan_bus(struct device *dev, void *data)
 964 {
 965         return to_ap_dev(dev)->qid == (ap_qid_t)(unsigned long) data;
 966 }
 967
 968 static void ap_device_release(struct device *dev)
 969 {
 970         struct ap_device *ap_dev = to_ap_dev(dev);
 971
 972         kfree(ap_dev);
 973 }
 974
 975 static void ap_scan_bus(struct work_struct *unused)
 976 {
 977         struct ap_device *ap_dev;
 978         struct device *dev;
 979         ap_qid_t qid;
 980         int queue_depth, device_type;
 981         int rc, i;
 982
 983         if (ap_select_domain() != 0)
 984                 return;
 985         for (i = 0; i < AP_DEVICES; i++) {
 986                 qid = AP_MKQID(i, ap_domain_index);
 987                 dev = bus_find_device(&ap_bus_type, NULL,
 988                                       (void *)(unsigned long)qid,
 989                                       __ap_scan_bus);
 990                 rc = ap_query_queue(qid, &queue_depth, &device_type);
 991                 if (dev) {
 992                         if (rc == -EBUSY) {
 993                                 set_current_state(TASK_UNINTERRUPTIBLE);
 994                                 schedule_timeout(AP_RESET_TIMEOUT);
 995                                 rc = ap_query_queue(qid, &queue_depth,
 996                                                     &device_type);
 997                         }
 998                         ap_dev = to_ap_dev(dev);
 999                         spin_lock_bh(&ap_dev->lock);
1000                         if (rc || ap_dev->unregistered) {
1001                                 spin_unlock_bh(&ap_dev->lock);
1002                                 device_unregister(dev);
1003                                 put_device(dev);
1004                                 continue;
1005                         }
1006                         spin_unlock_bh(&ap_dev->lock);
1007                         put_device(dev);
1008                         continue;
1009                 }
1010                 if (rc)
1011                         continue;
1012                 rc = ap_init_queue(qid);
1013                 if (rc)
1014                         continue;
1015                 ap_dev = kzalloc(sizeof(*ap_dev), GFP_KERNEL);
1016                 if (!ap_dev)
1017                         break;
1018                 ap_dev->qid = qid;
1019                 ap_dev->queue_depth = queue_depth;
1020                 ap_dev->unregistered = 1;
1021                 spin_lock_init(&ap_dev->lock);
1022                 INIT_LIST_HEAD(&ap_dev->pendingq);
1023                 INIT_LIST_HEAD(&ap_dev->requestq);
1024                 INIT_LIST_HEAD(&ap_dev->list);
1025                 setup_timer(&ap_dev->timeout, ap_request_timeout,
1026                             (unsigned long) ap_dev);
1027                 if (device_type == 0)
1028                         ap_probe_device_type(ap_dev);
1029                 else
1030                         ap_dev->device_type = device_type;
1031
1032                 ap_dev->device.bus = &ap_bus_type;
1033                 ap_dev->device.parent = ap_root_device;
1034                 dev_set_name(&ap_dev->device, "card%02x",
1035                              AP_QID_DEVICE(ap_dev->qid));
1036                 ap_dev->device.release = ap_device_release;
1037                 rc = device_register(&ap_dev->device);
1038                 if (rc) {
1039                         kfree(ap_dev);
1040                         continue;
1041                 }
1042                 /* Add device attributes. */
1043                 rc = sysfs_create_group(&ap_dev->device.kobj,
1044                                         &ap_dev_attr_group);
1045                 if (!rc) {
1046                         spin_lock_bh(&ap_dev->lock);
1047                         ap_dev->unregistered = 0;
1048                         spin_unlock_bh(&ap_dev->lock);
1049                 }
1050                 else
1051                         device_unregister(&ap_dev->device);
1052         }
1053 }
1054
1055 static void
1056 ap_config_timeout(unsigned long ptr)
1057 {
1058         queue_work(ap_work_queue, &ap_config_work);
1059         ap_config_timer.expires = jiffies + ap_config_time * HZ;
1060         add_timer(&ap_config_timer);
1061 }
1062
1063 /**
1064  * ap_schedule_poll_timer(): Schedule poll timer.
1065  *
1066  * Set up the timer to run the poll tasklet
1067  */
1068 static inline void ap_schedule_poll_timer(void)
1069 {
1070         if (ap_using_interrupts())
1071                 return;
1072         if (hrtimer_is_queued(&ap_poll_timer))
1073                 return;
1074         hrtimer_start(&ap_poll_timer, ktime_set(0, poll_timeout),
1075                       HRTIMER_MODE_ABS);
1076 }
1077
1078 /**
1079  * ap_poll_read(): Receive pending reply messages from an AP device.
1080  * @ap_dev: pointer to the AP device
1081  * @flags: pointer to control flags, bit 2^0 is set if another poll is
1082  *         required, bit 2^1 is set if the poll timer needs to get armed
1083  *
1084  * Returns 0 if the device is still present, -ENODEV if not.
1085  */
1086 static int ap_poll_read(struct ap_device *ap_dev, unsigned long *flags)
1087 {
1088         struct ap_queue_status status;
1089         struct ap_message *ap_msg;
1090
1091         if (ap_dev->queue_count <= 0)
1092                 return 0;
1093         status = __ap_recv(ap_dev->qid, &ap_dev->reply->psmid,
1094                            ap_dev->reply->message, ap_dev->reply->length);
1095         switch (status.response_code) {
1096         case AP_RESPONSE_NORMAL:
1097                 atomic_dec(&ap_poll_requests);
1098                 ap_decrease_queue_count(ap_dev);
1099                 list_for_each_entry(ap_msg, &ap_dev->pendingq, list) {
1100                         if (ap_msg->psmid != ap_dev->reply->psmid)
1101                                 continue;
1102                         list_del_init(&ap_msg->list);
1103                         ap_dev->pendingq_count--;
1104                         ap_dev->drv->receive(ap_dev, ap_msg, ap_dev->reply);
1105                         break;
1106                 }
1107                 if (ap_dev->queue_count > 0)
1108                         *flags |= 1;
1109                 break;
1110         case AP_RESPONSE_NO_PENDING_REPLY:
1111                 if (status.queue_empty) {
1112                         /* The card shouldn't forget requests but who knows. */
1113                         atomic_sub(ap_dev->queue_count, &ap_poll_requests);
1114                         ap_dev->queue_count = 0;
1115                         list_splice_init(&ap_dev->pendingq, &ap_dev->requestq);
1116                         ap_dev->requestq_count += ap_dev->pendingq_count;
1117                         ap_dev->pendingq_count = 0;
1118                 } else
1119                         *flags |= 2;
1120                 break;
1121         default:
1122                 return -ENODEV;
1123         }
1124         return 0;
1125 }
1126
1127 /**
1128  * ap_poll_write(): Send messages from the request queue to an AP device.
1129  * @ap_dev: pointer to the AP device
1130  * @flags: pointer to control flags, bit 2^0 is set if another poll is
1131  *         required, bit 2^1 is set if the poll timer needs to get armed
1132  *
1133  * Returns 0 if the device is still present, -ENODEV if not.
1134  */
1135 static int ap_poll_write(struct ap_device *ap_dev, unsigned long *flags)
1136 {
1137         struct ap_queue_status status;
1138         struct ap_message *ap_msg;
1139
1140         if (ap_dev->requestq_count <= 0 ||
1141             ap_dev->queue_count >= ap_dev->queue_depth)
1142                 return 0;
1143         /* Start the next request on the queue. */
1144         ap_msg = list_entry(ap_dev->requestq.next, struct ap_message, list);
1145         status = __ap_send(ap_dev->qid, ap_msg->psmid,
1146                            ap_msg->message, ap_msg->length);
1147         switch (status.response_code) {
1148         case AP_RESPONSE_NORMAL:
1149                 atomic_inc(&ap_poll_requests);
1150                 ap_increase_queue_count(ap_dev);
1151                 list_move_tail(&ap_msg->list, &ap_dev->pendingq);
1152                 ap_dev->requestq_count--;
1153                 ap_dev->pendingq_count++;
1154                 if (ap_dev->queue_count < ap_dev->queue_depth &&
1155                     ap_dev->requestq_count > 0)
1156                         *flags |= 1;
1157                 *flags |= 2;
1158                 break;
1159         case AP_RESPONSE_Q_FULL:
1160         case AP_RESPONSE_RESET_IN_PROGRESS:
1161                 *flags |= 2;
1162                 break;
1163         case AP_RESPONSE_MESSAGE_TOO_BIG:
1164                 return -EINVAL;
1165         default:
1166                 return -ENODEV;
1167         }
1168         return 0;
1169 }
1170
1171 /**
1172  * ap_poll_queue(): Poll AP device for pending replies and send new messages.
1173  * @ap_dev: pointer to the bus device
1174  * @flags: pointer to control flags, bit 2^0 is set if another poll is
1175  *         required, bit 2^1 is set if the poll timer needs to get armed
1176  *
1177  * Poll AP device for pending replies and send new messages. If either
1178  * ap_poll_read or ap_poll_write returns -ENODEV unregister the device.
1179  * Returns 0.
1180  */
1181 static inline int ap_poll_queue(struct ap_device *ap_dev, unsigned long *flags)
1182 {
1183         int rc;
1184
1185         rc = ap_poll_read(ap_dev, flags);
1186         if (rc)
1187                 return rc;
1188         return ap_poll_write(ap_dev, flags);
1189 }
1190
1191 /**
1192  * __ap_queue_message(): Queue a message to a device.
1193  * @ap_dev: pointer to the AP device
1194  * @ap_msg: the message to be queued
1195  *
1196  * Queue a message to a device. Returns 0 if successful.
1197  */
1198 static int __ap_queue_message(struct ap_device *ap_dev, struct ap_message *ap_msg)
1199 {
1200         struct ap_queue_status status;
1201
1202         if (list_empty(&ap_dev->requestq) &&
1203             ap_dev->queue_count < ap_dev->queue_depth) {
1204                 status = __ap_send(ap_dev->qid, ap_msg->psmid,
1205                                    ap_msg->message, ap_msg->length);
1206                 switch (status.response_code) {
1207                 case AP_RESPONSE_NORMAL:
1208                         list_add_tail(&ap_msg->list, &ap_dev->pendingq);
1209                         atomic_inc(&ap_poll_requests);
1210                         ap_dev->pendingq_count++;
1211                         ap_increase_queue_count(ap_dev);
1212                         ap_dev->total_request_count++;
1213                         break;
1214                 case AP_RESPONSE_Q_FULL:
1215                 case AP_RESPONSE_RESET_IN_PROGRESS:
1216                         list_add_tail(&ap_msg->list, &ap_dev->requestq);
1217                         ap_dev->requestq_count++;
1218                         ap_dev->total_request_count++;
1219                         return -EBUSY;
1220                 case AP_RESPONSE_MESSAGE_TOO_BIG:
1221                         ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-EINVAL));
1222                         return -EINVAL;
1223                 default:        /* Device is gone. */
1224                         ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV));
1225                         return -ENODEV;
1226                 }
1227         } else {
1228                 list_add_tail(&ap_msg->list, &ap_dev->requestq);
1229                 ap_dev->requestq_count++;
1230                 ap_dev->total_request_count++;
1231                 return -EBUSY;
1232         }
1233         ap_schedule_poll_timer();
1234         return 0;
1235 }
1236
1237 void ap_queue_message(struct ap_device *ap_dev, struct ap_message *ap_msg)
1238 {
1239         unsigned long flags;
1240         int rc;
1241
1242         spin_lock_bh(&ap_dev->lock);
1243         if (!ap_dev->unregistered) {
1244                 /* Make room on the queue by polling for finished requests. */
1245                 rc = ap_poll_queue(ap_dev, &flags);
1246                 if (!rc)
1247                         rc = __ap_queue_message(ap_dev, ap_msg);
1248                 if (!rc)
1249                         wake_up(&ap_poll_wait);
1250                 if (rc == -ENODEV)
1251                         ap_dev->unregistered = 1;
1252         } else {
1253                 ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV));
1254                 rc = -ENODEV;
1255         }
1256         spin_unlock_bh(&ap_dev->lock);
1257         if (rc == -ENODEV)
1258                 device_unregister(&ap_dev->device);
1259 }
1260 EXPORT_SYMBOL(ap_queue_message);
1261
1262 /**
1263  * ap_cancel_message(): Cancel a crypto request.
1264  * @ap_dev: The AP device that has the message queued
1265  * @ap_msg: The message that is to be removed
1266  *
1267  * Cancel a crypto request. This is done by removing the request
1268  * from the device pending or request queue. Note that the
1269  * request stays on the AP queue. When it finishes the message
1270  * reply will be discarded because the psmid can't be found.
1271  */
1272 void ap_cancel_message(struct ap_device *ap_dev, struct ap_message *ap_msg)
1273 {
1274         struct ap_message *tmp;
1275
1276         spin_lock_bh(&ap_dev->lock);
1277         if (!list_empty(&ap_msg->list)) {
1278                 list_for_each_entry(tmp, &ap_dev->pendingq, list)
1279                         if (tmp->psmid == ap_msg->psmid) {
1280                                 ap_dev->pendingq_count--;
1281                                 goto found;
1282                         }
1283                 ap_dev->requestq_count--;
1284         found:
1285                 list_del_init(&ap_msg->list);
1286         }
1287         spin_unlock_bh(&ap_dev->lock);
1288 }
1289 EXPORT_SYMBOL(ap_cancel_message);
1290
1291 /**
1292  * ap_poll_timeout(): AP receive polling for finished AP requests.
1293  * @unused: Unused pointer.
1294  *
1295  * Schedules the AP tasklet using a high resolution timer.
1296  */
1297 static enum hrtimer_restart ap_poll_timeout(struct hrtimer *unused)
1298 {
1299         tasklet_schedule(&ap_tasklet);
1300         return HRTIMER_NORESTART;
1301 }
1302
1303 /**
1304  * ap_reset(): Reset a not responding AP device.
1305  * @ap_dev: Pointer to the AP device
1306  *
1307  * Reset a not responding AP device and move all requests from the
1308  * pending queue to the request queue.
1309  */
1310 static void ap_reset(struct ap_device *ap_dev)
1311 {
1312         int rc;
1313
1314         ap_dev->reset = AP_RESET_IGNORE;
1315         atomic_sub(ap_dev->queue_count, &ap_poll_requests);
1316         ap_dev->queue_count = 0;
1317         list_splice_init(&ap_dev->pendingq, &ap_dev->requestq);
1318         ap_dev->requestq_count += ap_dev->pendingq_count;
1319         ap_dev->pendingq_count = 0;
1320         rc = ap_init_queue(ap_dev->qid);
1321         if (rc == -ENODEV)
1322                 ap_dev->unregistered = 1;
1323 }
1324
1325 static int __ap_poll_device(struct ap_device *ap_dev, unsigned long *flags)
1326 {
1327         spin_lock(&ap_dev->lock);
1328         if (!ap_dev->unregistered) {
1329                 if (ap_poll_queue(ap_dev, flags))
1330                         ap_dev->unregistered = 1;
1331                 if (ap_dev->reset == AP_RESET_DO)
1332                         ap_reset(ap_dev);
1333         }
1334         spin_unlock(&ap_dev->lock);
1335         return 0;
1336 }
1337
1338 /**
1339  * ap_poll_all(): Poll all AP devices.
1340  * @dummy: Unused variable
1341  *
1342  * Poll all AP devices on the bus in a round robin fashion. Continue
1343  * polling until bit 2^0 of the control flags is not set. If bit 2^1
1344  * of the control flags has been set arm the poll timer.
1345  */
1346 static void ap_poll_all(unsigned long dummy)
1347 {
1348         unsigned long flags;
1349         struct ap_device *ap_dev;
1350
1351         /* Reset the indicator if interrupts are used. Thus new interrupts can
1352          * be received. Doing it in the beginning of the tasklet is therefor
1353          * important that no requests on any AP get lost.
1354          */
1355         if (ap_using_interrupts())
1356                 xchg((u8 *)ap_interrupt_indicator, 0);
1357         do {
1358                 flags = 0;
1359                 spin_lock(&ap_device_list_lock);
1360                 list_for_each_entry(ap_dev, &ap_device_list, list) {
1361                         __ap_poll_device(ap_dev, &flags);
1362                 }
1363                 spin_unlock(&ap_device_list_lock);
1364         } while (flags & 1);
1365         if (flags & 2)
1366                 ap_schedule_poll_timer();
1367 }
1368
1369 /**
1370  * ap_poll_thread(): Thread that polls for finished requests.
1371  * @data: Unused pointer
1372  *
1373  * AP bus poll thread. The purpose of this thread is to poll for
1374  * finished requests in a loop if there is a "free" cpu - that is
1375  * a cpu that doesn't have anything better to do. The polling stops
1376  * as soon as there is another task or if all messages have been
1377  * delivered.
1378  */
1379 static int ap_poll_thread(void *data)
1380 {
1381         DECLARE_WAITQUEUE(wait, current);
1382         unsigned long flags;
1383         int requests;
1384         struct ap_device *ap_dev;
1385
1386         set_user_nice(current, 19);
1387         while (1) {
1388                 if (need_resched()) {
1389                         schedule();
1390                         continue;
1391                 }
1392                 add_wait_queue(&ap_poll_wait, &wait);
1393                 set_current_state(TASK_INTERRUPTIBLE);
1394                 if (kthread_should_stop())
1395                         break;
1396                 requests = atomic_read(&ap_poll_requests);
1397                 if (requests <= 0)
1398                         schedule();
1399                 set_current_state(TASK_RUNNING);
1400                 remove_wait_queue(&ap_poll_wait, &wait);
1401
1402                 flags = 0;
1403                 spin_lock_bh(&ap_device_list_lock);
1404                 list_for_each_entry(ap_dev, &ap_device_list, list) {
1405                         __ap_poll_device(ap_dev, &flags);
1406                 }
1407                 spin_unlock_bh(&ap_device_list_lock);
1408         }
1409         set_current_state(TASK_RUNNING);
1410         remove_wait_queue(&ap_poll_wait, &wait);
1411         return 0;
1412 }
1413
1414 static int ap_poll_thread_start(void)
1415 {
1416         int rc;
1417
1418         if (ap_using_interrupts())
1419                 return 0;
1420         mutex_lock(&ap_poll_thread_mutex);
1421         if (!ap_poll_kthread) {
1422                 ap_poll_kthread = kthread_run(ap_poll_thread, NULL, "appoll");
1423                 rc = IS_ERR(ap_poll_kthread) ? PTR_ERR(ap_poll_kthread) : 0;
1424                 if (rc)
1425                         ap_poll_kthread = NULL;
1426         }
1427         else
1428                 rc = 0;
1429         mutex_unlock(&ap_poll_thread_mutex);
1430         return rc;
1431 }
1432
1433 static void ap_poll_thread_stop(void)
1434 {
1435         mutex_lock(&ap_poll_thread_mutex);
1436         if (ap_poll_kthread) {
1437                 kthread_stop(ap_poll_kthread);
1438                 ap_poll_kthread = NULL;
1439         }
1440         mutex_unlock(&ap_poll_thread_mutex);
1441 }
1442
1443 /**
1444  * ap_request_timeout(): Handling of request timeouts
1445  * @data: Holds the AP device.
1446  *
1447  * Handles request timeouts.
1448  */
1449 static void ap_request_timeout(unsigned long data)
1450 {
1451         struct ap_device *ap_dev = (struct ap_device *) data;
1452
1453         if (ap_dev->reset == AP_RESET_ARMED) {
1454                 ap_dev->reset = AP_RESET_DO;
1455
1456                 if (ap_using_interrupts())
1457                         tasklet_schedule(&ap_tasklet);
1458         }
1459 }
1460
1461 static void ap_reset_domain(void)
1462 {
1463         int i;
1464
1465         if (ap_domain_index != -1)
1466                 for (i = 0; i < AP_DEVICES; i++)
1467                         ap_reset_queue(AP_MKQID(i, ap_domain_index));
1468 }
1469
1470 static void ap_reset_all(void)
1471 {
1472         int i, j;
1473
1474         for (i = 0; i < AP_DOMAINS; i++)
1475                 for (j = 0; j < AP_DEVICES; j++)
1476                         ap_reset_queue(AP_MKQID(j, i));
1477 }
1478
1479 static struct reset_call ap_reset_call = {
1480         .fn = ap_reset_all,
1481 };
1482
1483 /**
1484  * ap_module_init(): The module initialization code.
1485  *
1486  * Initializes the module.
1487  */
1488 int __init ap_module_init(void)
1489 {
1490         int rc, i;
1491
1492         if (ap_domain_index < -1 || ap_domain_index >= AP_DOMAINS) {
1493                 pr_warning("%d is not a valid cryptographic domain\n",
1494                            ap_domain_index);
1495                 return -EINVAL;
1496         }
1497         if (ap_instructions_available() != 0) {
1498                 pr_warning("The hardware system does not support "
1499                            "AP instructions\n");
1500                 return -ENODEV;
1501         }
1502         if (ap_interrupts_available()) {
1503                 isc_register(AP_ISC);
1504                 ap_interrupt_indicator = s390_register_adapter_interrupt(
1505                         &ap_interrupt_handler, NULL, AP_ISC);
1506                 if (IS_ERR(ap_interrupt_indicator)) {
1507                         ap_interrupt_indicator = NULL;
1508                         isc_unregister(AP_ISC);
1509                 }
1510         }
1511
1512         register_reset_call(&ap_reset_call);
1513
1514         /* Create /sys/bus/ap. */
1515         rc = bus_register(&ap_bus_type);
1516         if (rc)
1517                 goto out;
1518         for (i = 0; ap_bus_attrs[i]; i++) {
1519                 rc = bus_create_file(&ap_bus_type, ap_bus_attrs[i]);
1520                 if (rc)
1521                         goto out_bus;
1522         }
1523
1524         /* Create /sys/devices/ap. */
1525         ap_root_device = s390_root_dev_register("ap");
1526         rc = IS_ERR(ap_root_device) ? PTR_ERR(ap_root_device) : 0;
1527         if (rc)
1528                 goto out_bus;
1529
1530         ap_work_queue = create_singlethread_workqueue("kapwork");
1531         if (!ap_work_queue) {
1532                 rc = -ENOMEM;
1533                 goto out_root;
1534         }
1535
1536         if (ap_select_domain() == 0)
1537                 ap_scan_bus(NULL);
1538
1539         /* Setup the AP bus rescan timer. */
1540         init_timer(&ap_config_timer);
1541         ap_config_timer.function = ap_config_timeout;
1542         ap_config_timer.data = 0;
1543         ap_config_timer.expires = jiffies + ap_config_time * HZ;
1544         add_timer(&ap_config_timer);
1545
1546         /* Setup the high resultion poll timer.
1547          * If we are running under z/VM adjust polling to z/VM polling rate.
1548          */
1549         if (MACHINE_IS_VM)
1550                 poll_timeout = 1500000;
1551         hrtimer_init(&ap_poll_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
1552         ap_poll_timer.function = ap_poll_timeout;
1553
1554         /* Start the low priority AP bus poll thread. */
1555         if (ap_thread_flag) {
1556                 rc = ap_poll_thread_start();
1557                 if (rc)
1558                         goto out_work;
1559         }
1560
1561         return 0;
1562
1563 out_work:
1564         del_timer_sync(&ap_config_timer);
1565         hrtimer_cancel(&ap_poll_timer);
1566         destroy_workqueue(ap_work_queue);
1567 out_root:
1568         s390_root_dev_unregister(ap_root_device);
1569 out_bus:
1570         while (i--)
1571                 bus_remove_file(&ap_bus_type, ap_bus_attrs[i]);
1572         bus_unregister(&ap_bus_type);
1573 out:
1574         unregister_reset_call(&ap_reset_call);
1575         if (ap_using_interrupts()) {
1576                 s390_unregister_adapter_interrupt(ap_interrupt_indicator, AP_ISC);
1577                 isc_unregister(AP_ISC);
1578         }
1579         return rc;
1580 }
1581
1582 static int __ap_match_all(struct device *dev, void *data)
1583 {
1584         return 1;
1585 }
1586
1587 /**
1588  * ap_modules_exit(): The module termination code
1589  *
1590  * Terminates the module.
1591  */
1592 void ap_module_exit(void)
1593 {
1594         int i;
1595         struct device *dev;
1596
1597         ap_reset_domain();
1598         ap_poll_thread_stop();
1599         del_timer_sync(&ap_config_timer);
1600         hrtimer_cancel(&ap_poll_timer);
1601         destroy_workqueue(ap_work_queue);
1602         tasklet_kill(&ap_tasklet);
1603         s390_root_dev_unregister(ap_root_device);
1604         while ((dev = bus_find_device(&ap_bus_type, NULL, NULL,
1605                     __ap_match_all)))
1606         {
1607                 device_unregister(dev);
1608                 put_device(dev);
1609         }
1610         for (i = 0; ap_bus_attrs[i]; i++)
1611                 bus_remove_file(&ap_bus_type, ap_bus_attrs[i]);
1612         bus_unregister(&ap_bus_type);
1613         unregister_reset_call(&ap_reset_call);
1614         if (ap_using_interrupts()) {
1615                 s390_unregister_adapter_interrupt(ap_interrupt_indicator, AP_ISC);
1616                 isc_unregister(AP_ISC);
1617         }
1618 }
1619
1620 #ifndef CONFIG_ZCRYPT_MONOLITHIC
1621 module_init(ap_module_init);
1622 module_exit(ap_module_exit);
1623 #endif