linux/net/iucv/iucv.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * IUCV base infrastructure.
   4 *
   5 * Copyright IBM Corp. 2001, 2009
   6 *
   7 * Author(s):
   8 *    Original source:
   9 *      Alan Altmark (Alan_Altmark@us.ibm.com)  Sept. 2000
  10 *      Xenia Tkatschow (xenia@us.ibm.com)
  11 *    2Gb awareness and general cleanup:
  12 *      Fritz Elfert (elfert@de.ibm.com, felfert@millenux.com)
  13 *    Rewritten for af_iucv:
  14 *      Martin Schwidefsky <schwidefsky@de.ibm.com>
  15 *    PM functions:
  16 *      Ursula Braun (ursula.braun@de.ibm.com)
  17 *
  18 * Documentation used:
  19 *    The original source
  20 *    CP Programming Service, IBM document # SC24-5760
  21 */
  22
  23#define KMSG_COMPONENT "iucv"
  24#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  25
  26#include <linux/kernel_stat.h>
  27#include <linux/module.h>
  28#include <linux/moduleparam.h>
  29#include <linux/spinlock.h>
  30#include <linux/kernel.h>
  31#include <linux/slab.h>
  32#include <linux/init.h>
  33#include <linux/interrupt.h>
  34#include <linux/list.h>
  35#include <linux/errno.h>
  36#include <linux/err.h>
  37#include <linux/device.h>
  38#include <linux/cpu.h>
  39#include <linux/reboot.h>
  40#include <net/iucv/iucv.h>
  41#include <linux/atomic.h>
  42#include <asm/ebcdic.h>
  43#include <asm/io.h>
  44#include <asm/irq.h>
  45#include <asm/smp.h>
  46
  47/*
  48 * FLAGS:
  49 * All flags are defined in the field IPFLAGS1 of each function
  50 * and can be found in CP Programming Services.
  51 * IPSRCCLS - Indicates you have specified a source class.
  52 * IPTRGCLS - Indicates you have specified a target class.
  53 * IPFGPID  - Indicates you have specified a pathid.
  54 * IPFGMID  - Indicates you have specified a message ID.
  55 * IPNORPY  - Indicates a one-way message. No reply expected.
  56 * IPALL    - Indicates that all paths are affected.
  57 */
  58#define IUCV_IPSRCCLS   0x01
  59#define IUCV_IPTRGCLS   0x01
  60#define IUCV_IPFGPID    0x02
  61#define IUCV_IPFGMID    0x04
  62#define IUCV_IPNORPY    0x10
  63#define IUCV_IPALL      0x80
  64
  65static int iucv_bus_match(struct device *dev, struct device_driver *drv)
  66{
  67        return 0;
  68}
  69
  70struct bus_type iucv_bus = {
  71        .name = "iucv",
  72        .match = iucv_bus_match,
  73};
  74EXPORT_SYMBOL(iucv_bus);
  75
  76struct device *iucv_root;
  77EXPORT_SYMBOL(iucv_root);
  78
  79static int iucv_available;
  80
  81/* General IUCV interrupt structure */
  82struct iucv_irq_data {
  83        u16 ippathid;
  84        u8  ipflags1;
  85        u8  iptype;
  86        u32 res2[8];
  87};
  88
  89struct iucv_irq_list {
  90        struct list_head list;
  91        struct iucv_irq_data data;
  92};
  93
  94static struct iucv_irq_data *iucv_irq_data[NR_CPUS];
  95static cpumask_t iucv_buffer_cpumask = { CPU_BITS_NONE };
  96static cpumask_t iucv_irq_cpumask = { CPU_BITS_NONE };
  97
  98/*
  99 * Queue of interrupt buffers lock for delivery via the tasklet
 100 * (fast but can't call smp_call_function).
 101 */
 102static LIST_HEAD(iucv_task_queue);
 103
 104/*
 105 * The tasklet for fast delivery of iucv interrupts.
 106 */
 107static void iucv_tasklet_fn(unsigned long);
 108static DECLARE_TASKLET_OLD(iucv_tasklet, iucv_tasklet_fn);
 109
 110/*
 111 * Queue of interrupt buffers for delivery via a work queue
 112 * (slower but can call smp_call_function).
 113 */
 114static LIST_HEAD(iucv_work_queue);
 115
 116/*
 117 * The work element to deliver path pending interrupts.
 118 */
 119static void iucv_work_fn(struct work_struct *work);
 120static DECLARE_WORK(iucv_work, iucv_work_fn);
 121
 122/*
 123 * Spinlock protecting task and work queue.
 124 */
 125static DEFINE_SPINLOCK(iucv_queue_lock);
 126
 127enum iucv_command_codes {
 128        IUCV_QUERY = 0,
 129        IUCV_RETRIEVE_BUFFER = 2,
 130        IUCV_SEND = 4,
 131        IUCV_RECEIVE = 5,
 132        IUCV_REPLY = 6,
 133        IUCV_REJECT = 8,
 134        IUCV_PURGE = 9,
 135        IUCV_ACCEPT = 10,
 136        IUCV_CONNECT = 11,
 137        IUCV_DECLARE_BUFFER = 12,
 138        IUCV_QUIESCE = 13,
 139        IUCV_RESUME = 14,
 140        IUCV_SEVER = 15,
 141        IUCV_SETMASK = 16,
 142        IUCV_SETCONTROLMASK = 17,
 143};
 144
 145/*
 146 * Error messages that are used with the iucv_sever function. They get
 147 * converted to EBCDIC.
 148 */
 149static char iucv_error_no_listener[16] = "NO LISTENER";
 150static char iucv_error_no_memory[16] = "NO MEMORY";
 151static char iucv_error_pathid[16] = "INVALID PATHID";
 152
 153/*
 154 * iucv_handler_list: List of registered handlers.
 155 */
 156static LIST_HEAD(iucv_handler_list);
 157
 158/*
 159 * iucv_path_table: an array of iucv_path structures.
 160 */
 161static struct iucv_path **iucv_path_table;
 162static unsigned long iucv_max_pathid;
 163
 164/*
 165 * iucv_lock: spinlock protecting iucv_handler_list and iucv_pathid_table
 166 */
 167static DEFINE_SPINLOCK(iucv_table_lock);
 168
 169/*
 170 * iucv_active_cpu: contains the number of the cpu executing the tasklet
 171 * or the work handler. Needed for iucv_path_sever called from tasklet.
 172 */
 173static int iucv_active_cpu = -1;
 174
 175/*
 176 * Mutex and wait queue for iucv_register/iucv_unregister.
 177 */
 178static DEFINE_MUTEX(iucv_register_mutex);
 179
 180/*
 181 * Counter for number of non-smp capable handlers.
 182 */
 183static int iucv_nonsmp_handler;
 184
 185/*
 186 * IUCV control data structure. Used by iucv_path_accept, iucv_path_connect,
 187 * iucv_path_quiesce and iucv_path_sever.
 188 */
 189struct iucv_cmd_control {
 190        u16 ippathid;
 191        u8  ipflags1;
 192        u8  iprcode;
 193        u16 ipmsglim;
 194        u16 res1;
 195        u8  ipvmid[8];
 196        u8  ipuser[16];
 197        u8  iptarget[8];
 198} __attribute__ ((packed,aligned(8)));
 199
 200/*
 201 * Data in parameter list iucv structure. Used by iucv_message_send,
 202 * iucv_message_send2way and iucv_message_reply.
 203 */
 204struct iucv_cmd_dpl {
 205        u16 ippathid;
 206        u8  ipflags1;
 207        u8  iprcode;
 208        u32 ipmsgid;
 209        u32 iptrgcls;
 210        u8  iprmmsg[8];
 211        u32 ipsrccls;
 212        u32 ipmsgtag;
 213        u32 ipbfadr2;
 214        u32 ipbfln2f;
 215        u32 res;
 216} __attribute__ ((packed,aligned(8)));
 217
 218/*
 219 * Data in buffer iucv structure. Used by iucv_message_receive,
 220 * iucv_message_reject, iucv_message_send, iucv_message_send2way
 221 * and iucv_declare_cpu.
 222 */
 223struct iucv_cmd_db {
 224        u16 ippathid;
 225        u8  ipflags1;
 226        u8  iprcode;
 227        u32 ipmsgid;
 228        u32 iptrgcls;
 229        u32 ipbfadr1;
 230        u32 ipbfln1f;
 231        u32 ipsrccls;
 232        u32 ipmsgtag;
 233        u32 ipbfadr2;
 234        u32 ipbfln2f;
 235        u32 res;
 236} __attribute__ ((packed,aligned(8)));
 237
 238/*
 239 * Purge message iucv structure. Used by iucv_message_purge.
 240 */
 241struct iucv_cmd_purge {
 242        u16 ippathid;
 243        u8  ipflags1;
 244        u8  iprcode;
 245        u32 ipmsgid;
 246        u8  ipaudit[3];
 247        u8  res1[5];
 248        u32 res2;
 249        u32 ipsrccls;
 250        u32 ipmsgtag;
 251        u32 res3[3];
 252} __attribute__ ((packed,aligned(8)));
 253
 254/*
 255 * Set mask iucv structure. Used by iucv_enable_cpu.
 256 */
 257struct iucv_cmd_set_mask {
 258        u8  ipmask;
 259        u8  res1[2];
 260        u8  iprcode;
 261        u32 res2[9];
 262} __attribute__ ((packed,aligned(8)));
 263
 264union iucv_param {
 265        struct iucv_cmd_control ctrl;
 266        struct iucv_cmd_dpl dpl;
 267        struct iucv_cmd_db db;
 268        struct iucv_cmd_purge purge;
 269        struct iucv_cmd_set_mask set_mask;
 270};
 271
 272/*
 273 * Anchor for per-cpu IUCV command parameter block.
 274 */
 275static union iucv_param *iucv_param[NR_CPUS];
 276static union iucv_param *iucv_param_irq[NR_CPUS];
 277
 278/**
 279 * __iucv_call_b2f0
 280 * @command: identifier of IUCV call to CP.
 281 * @parm: pointer to a struct iucv_parm block
 282 *
 283 * Calls CP to execute IUCV commands.
 284 *
 285 * Returns the result of the CP IUCV call.
 286 */
 287static inline int __iucv_call_b2f0(int command, union iucv_param *parm)
 288{
 289        int cc;
 290
 291        asm volatile(
 292                "       lgr     0,%[reg0]\n"
 293                "       lgr     1,%[reg1]\n"
 294                "       .long   0xb2f01000\n"
 295                "       ipm     %[cc]\n"
 296                "       srl     %[cc],28\n"
 297                : [cc] "=&d" (cc), "+m" (*parm)
 298                : [reg0] "d" ((unsigned long)command),
 299                  [reg1] "d" ((unsigned long)parm)
 300                : "cc", "0", "1");
 301        return cc;
 302}
 303
 304static inline int iucv_call_b2f0(int command, union iucv_param *parm)
 305{
 306        int ccode;
 307
 308        ccode = __iucv_call_b2f0(command, parm);
 309        return ccode == 1 ? parm->ctrl.iprcode : ccode;
 310}
 311
 312/*
 313 * iucv_query_maxconn
 314 *
 315 * Determines the maximum number of connections that may be established.
 316 *
 317 * Returns the maximum number of connections or -EPERM is IUCV is not
 318 * available.
 319 */
 320static int __iucv_query_maxconn(void *param, unsigned long *max_pathid)
 321{
 322        unsigned long reg1 = virt_to_phys(param);
 323        int cc;
 324
 325        asm volatile (
 326                "       lghi    0,%[cmd]\n"
 327                "       lgr     1,%[reg1]\n"
 328                "       .long   0xb2f01000\n"
 329                "       ipm     %[cc]\n"
 330                "       srl     %[cc],28\n"
 331                "       lgr     %[reg1],1\n"
 332                : [cc] "=&d" (cc), [reg1] "+&d" (reg1)
 333                : [cmd] "K" (IUCV_QUERY)
 334                : "cc", "0", "1");
 335        *max_pathid = reg1;
 336        return cc;
 337}
 338
 339static int iucv_query_maxconn(void)
 340{
 341        unsigned long max_pathid;
 342        void *param;
 343        int ccode;
 344
 345        param = kzalloc(sizeof(union iucv_param), GFP_KERNEL | GFP_DMA);
 346        if (!param)
 347                return -ENOMEM;
 348        ccode = __iucv_query_maxconn(param, &max_pathid);
 349        if (ccode == 0)
 350                iucv_max_pathid = max_pathid;
 351        kfree(param);
 352        return ccode ? -EPERM : 0;
 353}
 354
 355/**
 356 * iucv_allow_cpu
 357 * @data: unused
 358 *
 359 * Allow iucv interrupts on this cpu.
 360 */
 361static void iucv_allow_cpu(void *data)
 362{
 363        int cpu = smp_processor_id();
 364        union iucv_param *parm;
 365
 366        /*
 367         * Enable all iucv interrupts.
 368         * ipmask contains bits for the different interrupts
 369         *      0x80 - Flag to allow nonpriority message pending interrupts
 370         *      0x40 - Flag to allow priority message pending interrupts
 371         *      0x20 - Flag to allow nonpriority message completion interrupts
 372         *      0x10 - Flag to allow priority message completion interrupts
 373         *      0x08 - Flag to allow IUCV control interrupts
 374         */
 375        parm = iucv_param_irq[cpu];
 376        memset(parm, 0, sizeof(union iucv_param));
 377        parm->set_mask.ipmask = 0xf8;
 378        iucv_call_b2f0(IUCV_SETMASK, parm);
 379
 380        /*
 381         * Enable all iucv control interrupts.
 382         * ipmask contains bits for the different interrupts
 383         *      0x80 - Flag to allow pending connections interrupts
 384         *      0x40 - Flag to allow connection complete interrupts
 385         *      0x20 - Flag to allow connection severed interrupts
 386         *      0x10 - Flag to allow connection quiesced interrupts
 387         *      0x08 - Flag to allow connection resumed interrupts
 388         */
 389        memset(parm, 0, sizeof(union iucv_param));
 390        parm->set_mask.ipmask = 0xf8;
 391        iucv_call_b2f0(IUCV_SETCONTROLMASK, parm);
 392        /* Set indication that iucv interrupts are allowed for this cpu. */
 393        cpumask_set_cpu(cpu, &iucv_irq_cpumask);
 394}
 395
 396/**
 397 * iucv_block_cpu
 398 * @data: unused
 399 *
 400 * Block iucv interrupts on this cpu.
 401 */
 402static void iucv_block_cpu(void *data)
 403{
 404        int cpu = smp_processor_id();
 405        union iucv_param *parm;
 406
 407        /* Disable all iucv interrupts. */
 408        parm = iucv_param_irq[cpu];
 409        memset(parm, 0, sizeof(union iucv_param));
 410        iucv_call_b2f0(IUCV_SETMASK, parm);
 411
 412        /* Clear indication that iucv interrupts are allowed for this cpu. */
 413        cpumask_clear_cpu(cpu, &iucv_irq_cpumask);
 414}
 415
 416/**
 417 * iucv_declare_cpu
 418 * @data: unused
 419 *
 420 * Declare a interrupt buffer on this cpu.
 421 */
 422static void iucv_declare_cpu(void *data)
 423{
 424        int cpu = smp_processor_id();
 425        union iucv_param *parm;
 426        int rc;
 427
 428        if (cpumask_test_cpu(cpu, &iucv_buffer_cpumask))
 429                return;
 430
 431        /* Declare interrupt buffer. */
 432        parm = iucv_param_irq[cpu];
 433        memset(parm, 0, sizeof(union iucv_param));
 434        parm->db.ipbfadr1 = virt_to_phys(iucv_irq_data[cpu]);
 435        rc = iucv_call_b2f0(IUCV_DECLARE_BUFFER, parm);
 436        if (rc) {
 437                char *err = "Unknown";
 438                switch (rc) {
 439                case 0x03:
 440                        err = "Directory error";
 441                        break;
 442                case 0x0a:
 443                        err = "Invalid length";
 444                        break;
 445                case 0x13:
 446                        err = "Buffer already exists";
 447                        break;
 448                case 0x3e:
 449                        err = "Buffer overlap";
 450                        break;
 451                case 0x5c:
 452                        err = "Paging or storage error";
 453                        break;
 454                }
 455                pr_warn("Defining an interrupt buffer on CPU %i failed with 0x%02x (%s)\n",
 456                        cpu, rc, err);
 457                return;
 458        }
 459
 460        /* Set indication that an iucv buffer exists for this cpu. */
 461        cpumask_set_cpu(cpu, &iucv_buffer_cpumask);
 462
 463        if (iucv_nonsmp_handler == 0 || cpumask_empty(&iucv_irq_cpumask))
 464                /* Enable iucv interrupts on this cpu. */
 465                iucv_allow_cpu(NULL);
 466        else
 467                /* Disable iucv interrupts on this cpu. */
 468                iucv_block_cpu(NULL);
 469}
 470
 471/**
 472 * iucv_retrieve_cpu
 473 * @data: unused
 474 *
 475 * Retrieve interrupt buffer on this cpu.
 476 */
 477static void iucv_retrieve_cpu(void *data)
 478{
 479        int cpu = smp_processor_id();
 480        union iucv_param *parm;
 481
 482        if (!cpumask_test_cpu(cpu, &iucv_buffer_cpumask))
 483                return;
 484
 485        /* Block iucv interrupts. */
 486        iucv_block_cpu(NULL);
 487
 488        /* Retrieve interrupt buffer. */
 489        parm = iucv_param_irq[cpu];
 490        iucv_call_b2f0(IUCV_RETRIEVE_BUFFER, parm);
 491
 492        /* Clear indication that an iucv buffer exists for this cpu. */
 493        cpumask_clear_cpu(cpu, &iucv_buffer_cpumask);
 494}
 495
 496/*
 497 * iucv_setmask_mp
 498 *
 499 * Allow iucv interrupts on all cpus.
 500 */
 501static void iucv_setmask_mp(void)
 502{
 503        int cpu;
 504
 505        cpus_read_lock();
 506        for_each_online_cpu(cpu)
 507                /* Enable all cpus with a declared buffer. */
 508                if (cpumask_test_cpu(cpu, &iucv_buffer_cpumask) &&
 509                    !cpumask_test_cpu(cpu, &iucv_irq_cpumask))
 510                        smp_call_function_single(cpu, iucv_allow_cpu,
 511                                                 NULL, 1);
 512        cpus_read_unlock();
 513}
 514
 515/*
 516 * iucv_setmask_up
 517 *
 518 * Allow iucv interrupts on a single cpu.
 519 */
 520static void iucv_setmask_up(void)
 521{
 522        cpumask_t cpumask;
 523        int cpu;
 524
 525        /* Disable all cpu but the first in cpu_irq_cpumask. */
 526        cpumask_copy(&cpumask, &iucv_irq_cpumask);
 527        cpumask_clear_cpu(cpumask_first(&iucv_irq_cpumask), &cpumask);
 528        for_each_cpu(cpu, &cpumask)
 529                smp_call_function_single(cpu, iucv_block_cpu, NULL, 1);
 530}
 531
 532/*
 533 * iucv_enable
 534 *
 535 * This function makes iucv ready for use. It allocates the pathid
 536 * table, declares an iucv interrupt buffer and enables the iucv
 537 * interrupts. Called when the first user has registered an iucv
 538 * handler.
 539 */
 540static int iucv_enable(void)
 541{
 542        size_t alloc_size;
 543        int cpu, rc;
 544
 545        cpus_read_lock();
 546        rc = -ENOMEM;
 547        alloc_size = iucv_max_pathid * sizeof(struct iucv_path);
 548        iucv_path_table = kzalloc(alloc_size, GFP_KERNEL);
 549        if (!iucv_path_table)
 550                goto out;
 551        /* Declare per cpu buffers. */
 552        rc = -EIO;
 553        for_each_online_cpu(cpu)
 554                smp_call_function_single(cpu, iucv_declare_cpu, NULL, 1);
 555        if (cpumask_empty(&iucv_buffer_cpumask))
 556                /* No cpu could declare an iucv buffer. */
 557                goto out;
 558        cpus_read_unlock();
 559        return 0;
 560out:
 561        kfree(iucv_path_table);
 562        iucv_path_table = NULL;
 563        cpus_read_unlock();
 564        return rc;
 565}
 566
 567/*
 568 * iucv_disable
 569 *
 570 * This function shuts down iucv. It disables iucv interrupts, retrieves
 571 * the iucv interrupt buffer and frees the pathid table. Called after the
 572 * last user unregister its iucv handler.
 573 */
 574static void iucv_disable(void)
 575{
 576        cpus_read_lock();
 577        on_each_cpu(iucv_retrieve_cpu, NULL, 1);
 578        kfree(iucv_path_table);
 579        iucv_path_table = NULL;
 580        cpus_read_unlock();
 581}
 582
 583static int iucv_cpu_dead(unsigned int cpu)
 584{
 585        kfree(iucv_param_irq[cpu]);
 586        iucv_param_irq[cpu] = NULL;
 587        kfree(iucv_param[cpu]);
 588        iucv_param[cpu] = NULL;
 589        kfree(iucv_irq_data[cpu]);
 590        iucv_irq_data[cpu] = NULL;
 591        return 0;
 592}
 593
 594static int iucv_cpu_prepare(unsigned int cpu)
 595{
 596        /* Note: GFP_DMA used to get memory below 2G */
 597        iucv_irq_data[cpu] = kmalloc_node(sizeof(struct iucv_irq_data),
 598                             GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
 599        if (!iucv_irq_data[cpu])
 600                goto out_free;
 601
 602        /* Allocate parameter blocks. */
 603        iucv_param[cpu] = kmalloc_node(sizeof(union iucv_param),
 604                          GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
 605        if (!iucv_param[cpu])
 606                goto out_free;
 607
 608        iucv_param_irq[cpu] = kmalloc_node(sizeof(union iucv_param),
 609                          GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
 610        if (!iucv_param_irq[cpu])
 611                goto out_free;
 612
 613        return 0;
 614
 615out_free:
 616        iucv_cpu_dead(cpu);
 617        return -ENOMEM;
 618}
 619
 620static int iucv_cpu_online(unsigned int cpu)
 621{
 622        if (!iucv_path_table)
 623                return 0;
 624        iucv_declare_cpu(NULL);
 625        return 0;
 626}
 627
 628static int iucv_cpu_down_prep(unsigned int cpu)
 629{
 630        cpumask_t cpumask;
 631
 632        if (!iucv_path_table)
 633                return 0;
 634
 635        cpumask_copy(&cpumask, &iucv_buffer_cpumask);
 636        cpumask_clear_cpu(cpu, &cpumask);
 637        if (cpumask_empty(&cpumask))
 638                /* Can't offline last IUCV enabled cpu. */
 639                return -EINVAL;
 640
 641        iucv_retrieve_cpu(NULL);
 642        if (!cpumask_empty(&iucv_irq_cpumask))
 643                return 0;
 644        smp_call_function_single(cpumask_first(&iucv_buffer_cpumask),
 645                                 iucv_allow_cpu, NULL, 1);
 646        return 0;
 647}
 648
 649/**
 650 * iucv_sever_pathid
 651 * @pathid: path identification number.
 652 * @userdata: 16-bytes of user data.
 653 *
 654 * Sever an iucv path to free up the pathid. Used internally.
 655 */
 656static int iucv_sever_pathid(u16 pathid, u8 *userdata)
 657{
 658        union iucv_param *parm;
 659
 660        parm = iucv_param_irq[smp_processor_id()];
 661        memset(parm, 0, sizeof(union iucv_param));
 662        if (userdata)
 663                memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 664        parm->ctrl.ippathid = pathid;
 665        return iucv_call_b2f0(IUCV_SEVER, parm);
 666}
 667
 668/**
 669 * __iucv_cleanup_queue
 670 * @dummy: unused dummy argument
 671 *
 672 * Nop function called via smp_call_function to force work items from
 673 * pending external iucv interrupts to the work queue.
 674 */
 675static void __iucv_cleanup_queue(void *dummy)
 676{
 677}
 678
 679/**
 680 * iucv_cleanup_queue
 681 *
 682 * Function called after a path has been severed to find all remaining
 683 * work items for the now stale pathid. The caller needs to hold the
 684 * iucv_table_lock.
 685 */
 686static void iucv_cleanup_queue(void)
 687{
 688        struct iucv_irq_list *p, *n;
 689
 690        /*
 691         * When a path is severed, the pathid can be reused immediately
 692         * on a iucv connect or a connection pending interrupt. Remove
 693         * all entries from the task queue that refer to a stale pathid
 694         * (iucv_path_table[ix] == NULL). Only then do the iucv connect
 695         * or deliver the connection pending interrupt. To get all the
 696         * pending interrupts force them to the work queue by calling
 697         * an empty function on all cpus.
 698         */
 699        smp_call_function(__iucv_cleanup_queue, NULL, 1);
 700        spin_lock_irq(&iucv_queue_lock);
 701        list_for_each_entry_safe(p, n, &iucv_task_queue, list) {
 702                /* Remove stale work items from the task queue. */
 703                if (iucv_path_table[p->data.ippathid] == NULL) {
 704                        list_del(&p->list);
 705                        kfree(p);
 706                }
 707        }
 708        spin_unlock_irq(&iucv_queue_lock);
 709}
 710
 711/**
 712 * iucv_register:
 713 * @handler: address of iucv handler structure
 714 * @smp: != 0 indicates that the handler can deal with out of order messages
 715 *
 716 * Registers a driver with IUCV.
 717 *
 718 * Returns 0 on success, -ENOMEM if the memory allocation for the pathid
 719 * table failed, or -EIO if IUCV_DECLARE_BUFFER failed on all cpus.
 720 */
 721int iucv_register(struct iucv_handler *handler, int smp)
 722{
 723        int rc;
 724
 725        if (!iucv_available)
 726                return -ENOSYS;
 727        mutex_lock(&iucv_register_mutex);
 728        if (!smp)
 729                iucv_nonsmp_handler++;
 730        if (list_empty(&iucv_handler_list)) {
 731                rc = iucv_enable();
 732                if (rc)
 733                        goto out_mutex;
 734        } else if (!smp && iucv_nonsmp_handler == 1)
 735                iucv_setmask_up();
 736        INIT_LIST_HEAD(&handler->paths);
 737
 738        spin_lock_bh(&iucv_table_lock);
 739        list_add_tail(&handler->list, &iucv_handler_list);
 740        spin_unlock_bh(&iucv_table_lock);
 741        rc = 0;
 742out_mutex:
 743        mutex_unlock(&iucv_register_mutex);
 744        return rc;
 745}
 746EXPORT_SYMBOL(iucv_register);
 747
 748/**
 749 * iucv_unregister
 750 * @handler:  address of iucv handler structure
 751 * @smp: != 0 indicates that the handler can deal with out of order messages
 752 *
 753 * Unregister driver from IUCV.
 754 */
 755void iucv_unregister(struct iucv_handler *handler, int smp)
 756{
 757        struct iucv_path *p, *n;
 758
 759        mutex_lock(&iucv_register_mutex);
 760        spin_lock_bh(&iucv_table_lock);
 761        /* Remove handler from the iucv_handler_list. */
 762        list_del_init(&handler->list);
 763        /* Sever all pathids still referring to the handler. */
 764        list_for_each_entry_safe(p, n, &handler->paths, list) {
 765                iucv_sever_pathid(p->pathid, NULL);
 766                iucv_path_table[p->pathid] = NULL;
 767                list_del(&p->list);
 768                iucv_path_free(p);
 769        }
 770        spin_unlock_bh(&iucv_table_lock);
 771        if (!smp)
 772                iucv_nonsmp_handler--;
 773        if (list_empty(&iucv_handler_list))
 774                iucv_disable();
 775        else if (!smp && iucv_nonsmp_handler == 0)
 776                iucv_setmask_mp();
 777        mutex_unlock(&iucv_register_mutex);
 778}
 779EXPORT_SYMBOL(iucv_unregister);
 780
 781static int iucv_reboot_event(struct notifier_block *this,
 782                             unsigned long event, void *ptr)
 783{
 784        int i;
 785
 786        if (cpumask_empty(&iucv_irq_cpumask))
 787                return NOTIFY_DONE;
 788
 789        cpus_read_lock();
 790        on_each_cpu_mask(&iucv_irq_cpumask, iucv_block_cpu, NULL, 1);
 791        preempt_disable();
 792        for (i = 0; i < iucv_max_pathid; i++) {
 793                if (iucv_path_table[i])
 794                        iucv_sever_pathid(i, NULL);
 795        }
 796        preempt_enable();
 797        cpus_read_unlock();
 798        iucv_disable();
 799        return NOTIFY_DONE;
 800}
 801
 802static struct notifier_block iucv_reboot_notifier = {
 803        .notifier_call = iucv_reboot_event,
 804};
 805
 806/**
 807 * iucv_path_accept
 808 * @path: address of iucv path structure
 809 * @handler: address of iucv handler structure
 810 * @userdata: 16 bytes of data reflected to the communication partner
 811 * @private: private data passed to interrupt handlers for this path
 812 *
 813 * This function is issued after the user received a connection pending
 814 * external interrupt and now wishes to complete the IUCV communication path.
 815 *
 816 * Returns the result of the CP IUCV call.
 817 */
 818int iucv_path_accept(struct iucv_path *path, struct iucv_handler *handler,
 819                     u8 *userdata, void *private)
 820{
 821        union iucv_param *parm;
 822        int rc;
 823
 824        local_bh_disable();
 825        if (cpumask_empty(&iucv_buffer_cpumask)) {
 826                rc = -EIO;
 827                goto out;
 828        }
 829        /* Prepare parameter block. */
 830        parm = iucv_param[smp_processor_id()];
 831        memset(parm, 0, sizeof(union iucv_param));
 832        parm->ctrl.ippathid = path->pathid;
 833        parm->ctrl.ipmsglim = path->msglim;
 834        if (userdata)
 835                memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 836        parm->ctrl.ipflags1 = path->flags;
 837
 838        rc = iucv_call_b2f0(IUCV_ACCEPT, parm);
 839        if (!rc) {
 840                path->private = private;
 841                path->msglim = parm->ctrl.ipmsglim;
 842                path->flags = parm->ctrl.ipflags1;
 843        }
 844out:
 845        local_bh_enable();
 846        return rc;
 847}
 848EXPORT_SYMBOL(iucv_path_accept);
 849
 850/**
 851 * iucv_path_connect
 852 * @path: address of iucv path structure
 853 * @handler: address of iucv handler structure
 854 * @userid: 8-byte user identification
 855 * @system: 8-byte target system identification
 856 * @userdata: 16 bytes of data reflected to the communication partner
 857 * @private: private data passed to interrupt handlers for this path
 858 *
 859 * This function establishes an IUCV path. Although the connect may complete
 860 * successfully, you are not able to use the path until you receive an IUCV
 861 * Connection Complete external interrupt.
 862 *
 863 * Returns the result of the CP IUCV call.
 864 */
 865int iucv_path_connect(struct iucv_path *path, struct iucv_handler *handler,
 866                      u8 *userid, u8 *system, u8 *userdata,
 867                      void *private)
 868{
 869        union iucv_param *parm;
 870        int rc;
 871
 872        spin_lock_bh(&iucv_table_lock);
 873        iucv_cleanup_queue();
 874        if (cpumask_empty(&iucv_buffer_cpumask)) {
 875                rc = -EIO;
 876                goto out;
 877        }
 878        parm = iucv_param[smp_processor_id()];
 879        memset(parm, 0, sizeof(union iucv_param));
 880        parm->ctrl.ipmsglim = path->msglim;
 881        parm->ctrl.ipflags1 = path->flags;
 882        if (userid) {
 883                memcpy(parm->ctrl.ipvmid, userid, sizeof(parm->ctrl.ipvmid));
 884                ASCEBC(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
 885                EBC_TOUPPER(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
 886        }
 887        if (system) {
 888                memcpy(parm->ctrl.iptarget, system,
 889                       sizeof(parm->ctrl.iptarget));
 890                ASCEBC(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
 891                EBC_TOUPPER(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
 892        }
 893        if (userdata)
 894                memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 895
 896        rc = iucv_call_b2f0(IUCV_CONNECT, parm);
 897        if (!rc) {
 898                if (parm->ctrl.ippathid < iucv_max_pathid) {
 899                        path->pathid = parm->ctrl.ippathid;
 900                        path->msglim = parm->ctrl.ipmsglim;
 901                        path->flags = parm->ctrl.ipflags1;
 902                        path->handler = handler;
 903                        path->private = private;
 904                        list_add_tail(&path->list, &handler->paths);
 905                        iucv_path_table[path->pathid] = path;
 906                } else {
 907                        iucv_sever_pathid(parm->ctrl.ippathid,
 908                                          iucv_error_pathid);
 909                        rc = -EIO;
 910                }
 911        }
 912out:
 913        spin_unlock_bh(&iucv_table_lock);
 914        return rc;
 915}
 916EXPORT_SYMBOL(iucv_path_connect);
 917
 918/**
 919 * iucv_path_quiesce:
 920 * @path: address of iucv path structure
 921 * @userdata: 16 bytes of data reflected to the communication partner
 922 *
 923 * This function temporarily suspends incoming messages on an IUCV path.
 924 * You can later reactivate the path by invoking the iucv_resume function.
 925 *
 926 * Returns the result from the CP IUCV call.
 927 */
 928int iucv_path_quiesce(struct iucv_path *path, u8 *userdata)
 929{
 930        union iucv_param *parm;
 931        int rc;
 932
 933        local_bh_disable();
 934        if (cpumask_empty(&iucv_buffer_cpumask)) {
 935                rc = -EIO;
 936                goto out;
 937        }
 938        parm = iucv_param[smp_processor_id()];
 939        memset(parm, 0, sizeof(union iucv_param));
 940        if (userdata)
 941                memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 942        parm->ctrl.ippathid = path->pathid;
 943        rc = iucv_call_b2f0(IUCV_QUIESCE, parm);
 944out:
 945        local_bh_enable();
 946        return rc;
 947}
 948EXPORT_SYMBOL(iucv_path_quiesce);
 949
 950/**
 951 * iucv_path_resume:
 952 * @path: address of iucv path structure
 953 * @userdata: 16 bytes of data reflected to the communication partner
 954 *
 955 * This function resumes incoming messages on an IUCV path that has
 956 * been stopped with iucv_path_quiesce.
 957 *
 958 * Returns the result from the CP IUCV call.
 959 */
 960int iucv_path_resume(struct iucv_path *path, u8 *userdata)
 961{
 962        union iucv_param *parm;
 963        int rc;
 964
 965        local_bh_disable();
 966        if (cpumask_empty(&iucv_buffer_cpumask)) {
 967                rc = -EIO;
 968                goto out;
 969        }
 970        parm = iucv_param[smp_processor_id()];
 971        memset(parm, 0, sizeof(union iucv_param));
 972        if (userdata)
 973                memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 974        parm->ctrl.ippathid = path->pathid;
 975        rc = iucv_call_b2f0(IUCV_RESUME, parm);
 976out:
 977        local_bh_enable();
 978        return rc;
 979}
 980
 981/**
 982 * iucv_path_sever
 983 * @path: address of iucv path structure
 984 * @userdata: 16 bytes of data reflected to the communication partner
 985 *
 986 * This function terminates an IUCV path.
 987 *
 988 * Returns the result from the CP IUCV call.
 989 */
 990int iucv_path_sever(struct iucv_path *path, u8 *userdata)
 991{
 992        int rc;
 993
 994        preempt_disable();
 995        if (cpumask_empty(&iucv_buffer_cpumask)) {
 996                rc = -EIO;
 997                goto out;
 998        }
 999        if (iucv_active_cpu != smp_processor_id())
1000                spin_lock_bh(&iucv_table_lock);
1001        rc = iucv_sever_pathid(path->pathid, userdata);
1002        iucv_path_table[path->pathid] = NULL;
1003        list_del_init(&path->list);
1004        if (iucv_active_cpu != smp_processor_id())
1005                spin_unlock_bh(&iucv_table_lock);
1006out:
1007        preempt_enable();
1008        return rc;
1009}
1010EXPORT_SYMBOL(iucv_path_sever);
1011
1012/**
1013 * iucv_message_purge
1014 * @path: address of iucv path structure
1015 * @msg: address of iucv msg structure
1016 * @srccls: source class of message
1017 *
1018 * Cancels a message you have sent.
1019 *
1020 * Returns the result from the CP IUCV call.
1021 */
1022int iucv_message_purge(struct iucv_path *path, struct iucv_message *msg,
1023                       u32 srccls)
1024{
1025        union iucv_param *parm;
1026        int rc;
1027
1028        local_bh_disable();
1029        if (cpumask_empty(&iucv_buffer_cpumask)) {
1030                rc = -EIO;
1031                goto out;
1032        }
1033        parm = iucv_param[smp_processor_id()];
1034        memset(parm, 0, sizeof(union iucv_param));
1035        parm->purge.ippathid = path->pathid;
1036        parm->purge.ipmsgid = msg->id;
1037        parm->purge.ipsrccls = srccls;
1038        parm->purge.ipflags1 = IUCV_IPSRCCLS | IUCV_IPFGMID | IUCV_IPFGPID;
1039        rc = iucv_call_b2f0(IUCV_PURGE, parm);
1040        if (!rc) {
1041                msg->audit = (*(u32 *) &parm->purge.ipaudit) >> 8;
1042                msg->tag = parm->purge.ipmsgtag;
1043        }
1044out:
1045        local_bh_enable();
1046        return rc;
1047}
1048EXPORT_SYMBOL(iucv_message_purge);
1049
1050/**
1051 * iucv_message_receive_iprmdata
1052 * @path: address of iucv path structure
1053 * @msg: address of iucv msg structure
1054 * @flags: how the message is received (IUCV_IPBUFLST)
1055 * @buffer: address of data buffer or address of struct iucv_array
1056 * @size: length of data buffer
1057 * @residual:
1058 *
1059 * Internal function used by iucv_message_receive and __iucv_message_receive
1060 * to receive RMDATA data stored in struct iucv_message.
1061 */
1062static int iucv_message_receive_iprmdata(struct iucv_path *path,
1063                                         struct iucv_message *msg,
1064                                         u8 flags, void *buffer,
1065                                         size_t size, size_t *residual)
1066{
1067        struct iucv_array *array;
1068        u8 *rmmsg;
1069        size_t copy;
1070
1071        /*
1072         * Message is 8 bytes long and has been stored to the
1073         * message descriptor itself.
1074         */
1075        if (residual)
1076                *residual = abs(size - 8);
1077        rmmsg = msg->rmmsg;
1078        if (flags & IUCV_IPBUFLST) {
1079                /* Copy to struct iucv_array. */
1080                size = (size < 8) ? size : 8;
1081                for (array = buffer; size > 0; array++) {
1082                        copy = min_t(size_t, size, array->length);
1083                        memcpy((u8 *)(addr_t) array->address,
1084                                rmmsg, copy);
1085                        rmmsg += copy;
1086                        size -= copy;
1087                }
1088        } else {
1089                /* Copy to direct buffer. */
1090                memcpy(buffer, rmmsg, min_t(size_t, size, 8));
1091        }
1092        return 0;
1093}
1094
1095/**
1096 * __iucv_message_receive
1097 * @path: address of iucv path structure
1098 * @msg: address of iucv msg structure
1099 * @flags: how the message is received (IUCV_IPBUFLST)
1100 * @buffer: address of data buffer or address of struct iucv_array
1101 * @size: length of data buffer
1102 * @residual:
1103 *
1104 * This function receives messages that are being sent to you over
1105 * established paths. This function will deal with RMDATA messages
1106 * embedded in struct iucv_message as well.
1107 *
1108 * Locking:     no locking
1109 *
1110 * Returns the result from the CP IUCV call.
1111 */
1112int __iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
1113                           u8 flags, void *buffer, size_t size, size_t *residual)
1114{
1115        union iucv_param *parm;
1116        int rc;
1117
1118        if (msg->flags & IUCV_IPRMDATA)
1119                return iucv_message_receive_iprmdata(path, msg, flags,
1120                                                     buffer, size, residual);
1121        if (cpumask_empty(&iucv_buffer_cpumask))
1122                return -EIO;
1123
1124        parm = iucv_param[smp_processor_id()];
1125        memset(parm, 0, sizeof(union iucv_param));
1126        parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1127        parm->db.ipbfln1f = (u32) size;
1128        parm->db.ipmsgid = msg->id;
1129        parm->db.ippathid = path->pathid;
1130        parm->db.iptrgcls = msg->class;
1131        parm->db.ipflags1 = (flags | IUCV_IPFGPID |
1132                             IUCV_IPFGMID | IUCV_IPTRGCLS);
1133        rc = iucv_call_b2f0(IUCV_RECEIVE, parm);
1134        if (!rc || rc == 5) {
1135                msg->flags = parm->db.ipflags1;
1136                if (residual)
1137                        *residual = parm->db.ipbfln1f;
1138        }
1139        return rc;
1140}
1141EXPORT_SYMBOL(__iucv_message_receive);
1142
1143/**
1144 * iucv_message_receive
1145 * @path: address of iucv path structure
1146 * @msg: address of iucv msg structure
1147 * @flags: how the message is received (IUCV_IPBUFLST)
1148 * @buffer: address of data buffer or address of struct iucv_array
1149 * @size: length of data buffer
1150 * @residual:
1151 *
1152 * This function receives messages that are being sent to you over
1153 * established paths. This function will deal with RMDATA messages
1154 * embedded in struct iucv_message as well.
1155 *
1156 * Locking:     local_bh_enable/local_bh_disable
1157 *
1158 * Returns the result from the CP IUCV call.
1159 */
1160int iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
1161                         u8 flags, void *buffer, size_t size, size_t *residual)
1162{
1163        int rc;
1164
1165        if (msg->flags & IUCV_IPRMDATA)
1166                return iucv_message_receive_iprmdata(path, msg, flags,
1167                                                     buffer, size, residual);
1168        local_bh_disable();
1169        rc = __iucv_message_receive(path, msg, flags, buffer, size, residual);
1170        local_bh_enable();
1171        return rc;
1172}
1173EXPORT_SYMBOL(iucv_message_receive);
1174
1175/**
1176 * iucv_message_reject
1177 * @path: address of iucv path structure
1178 * @msg: address of iucv msg structure
1179 *
1180 * The reject function refuses a specified message. Between the time you
1181 * are notified of a message and the time that you complete the message,
1182 * the message may be rejected.
1183 *
1184 * Returns the result from the CP IUCV call.
1185 */
1186int iucv_message_reject(struct iucv_path *path, struct iucv_message *msg)
1187{
1188        union iucv_param *parm;
1189        int rc;
1190
1191        local_bh_disable();
1192        if (cpumask_empty(&iucv_buffer_cpumask)) {
1193                rc = -EIO;
1194                goto out;
1195        }
1196        parm = iucv_param[smp_processor_id()];
1197        memset(parm, 0, sizeof(union iucv_param));
1198        parm->db.ippathid = path->pathid;
1199        parm->db.ipmsgid = msg->id;
1200        parm->db.iptrgcls = msg->class;
1201        parm->db.ipflags1 = (IUCV_IPTRGCLS | IUCV_IPFGMID | IUCV_IPFGPID);
1202        rc = iucv_call_b2f0(IUCV_REJECT, parm);
1203out:
1204        local_bh_enable();
1205        return rc;
1206}
1207EXPORT_SYMBOL(iucv_message_reject);
1208
1209/**
1210 * iucv_message_reply
1211 * @path: address of iucv path structure
1212 * @msg: address of iucv msg structure
1213 * @flags: how the reply is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1214 * @reply: address of reply data buffer or address of struct iucv_array
1215 * @size: length of reply data buffer
1216 *
1217 * This function responds to the two-way messages that you receive. You
1218 * must identify completely the message to which you wish to reply. ie,
1219 * pathid, msgid, and trgcls. Prmmsg signifies the data is moved into
1220 * the parameter list.
1221 *
1222 * Returns the result from the CP IUCV call.
1223 */
1224int iucv_message_reply(struct iucv_path *path, struct iucv_message *msg,
1225                       u8 flags, void *reply, size_t size)
1226{
1227        union iucv_param *parm;
1228        int rc;
1229
1230        local_bh_disable();
1231        if (cpumask_empty(&iucv_buffer_cpumask)) {
1232                rc = -EIO;
1233                goto out;
1234        }
1235        parm = iucv_param[smp_processor_id()];
1236        memset(parm, 0, sizeof(union iucv_param));
1237        if (flags & IUCV_IPRMDATA) {
1238                parm->dpl.ippathid = path->pathid;
1239                parm->dpl.ipflags1 = flags;
1240                parm->dpl.ipmsgid = msg->id;
1241                parm->dpl.iptrgcls = msg->class;
1242                memcpy(parm->dpl.iprmmsg, reply, min_t(size_t, size, 8));
1243        } else {
1244                parm->db.ipbfadr1 = (u32)(addr_t) reply;
1245                parm->db.ipbfln1f = (u32) size;
1246                parm->db.ippathid = path->pathid;
1247                parm->db.ipflags1 = flags;
1248                parm->db.ipmsgid = msg->id;
1249                parm->db.iptrgcls = msg->class;
1250        }
1251        rc = iucv_call_b2f0(IUCV_REPLY, parm);
1252out:
1253        local_bh_enable();
1254        return rc;
1255}
1256EXPORT_SYMBOL(iucv_message_reply);
1257
1258/**
1259 * __iucv_message_send
1260 * @path: address of iucv path structure
1261 * @msg: address of iucv msg structure
1262 * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1263 * @srccls: source class of message
1264 * @buffer: address of send buffer or address of struct iucv_array
1265 * @size: length of send buffer
1266 *
1267 * This function transmits data to another application. Data to be
1268 * transmitted is in a buffer and this is a one-way message and the
1269 * receiver will not reply to the message.
1270 *
1271 * Locking:     no locking
1272 *
1273 * Returns the result from the CP IUCV call.
1274 */
1275int __iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
1276                      u8 flags, u32 srccls, void *buffer, size_t size)
1277{
1278        union iucv_param *parm;
1279        int rc;
1280
1281        if (cpumask_empty(&iucv_buffer_cpumask)) {
1282                rc = -EIO;
1283                goto out;
1284        }
1285        parm = iucv_param[smp_processor_id()];
1286        memset(parm, 0, sizeof(union iucv_param));
1287        if (flags & IUCV_IPRMDATA) {
1288                /* Message of 8 bytes can be placed into the parameter list. */
1289                parm->dpl.ippathid = path->pathid;
1290                parm->dpl.ipflags1 = flags | IUCV_IPNORPY;
1291                parm->dpl.iptrgcls = msg->class;
1292                parm->dpl.ipsrccls = srccls;
1293                parm->dpl.ipmsgtag = msg->tag;
1294                memcpy(parm->dpl.iprmmsg, buffer, 8);
1295        } else {
1296                parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1297                parm->db.ipbfln1f = (u32) size;
1298                parm->db.ippathid = path->pathid;
1299                parm->db.ipflags1 = flags | IUCV_IPNORPY;
1300                parm->db.iptrgcls = msg->class;
1301                parm->db.ipsrccls = srccls;
1302                parm->db.ipmsgtag = msg->tag;
1303        }
1304        rc = iucv_call_b2f0(IUCV_SEND, parm);
1305        if (!rc)
1306                msg->id = parm->db.ipmsgid;
1307out:
1308        return rc;
1309}
1310EXPORT_SYMBOL(__iucv_message_send);
1311
1312/**
1313 * iucv_message_send
1314 * @path: address of iucv path structure
1315 * @msg: address of iucv msg structure
1316 * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1317 * @srccls: source class of message
1318 * @buffer: address of send buffer or address of struct iucv_array
1319 * @size: length of send buffer
1320 *
1321 * This function transmits data to another application. Data to be
1322 * transmitted is in a buffer and this is a one-way message and the
1323 * receiver will not reply to the message.
1324 *
1325 * Locking:     local_bh_enable/local_bh_disable
1326 *
1327 * Returns the result from the CP IUCV call.
1328 */
1329int iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
1330                      u8 flags, u32 srccls, void *buffer, size_t size)
1331{
1332        int rc;
1333
1334        local_bh_disable();
1335        rc = __iucv_message_send(path, msg, flags, srccls, buffer, size);
1336        local_bh_enable();
1337        return rc;
1338}
1339EXPORT_SYMBOL(iucv_message_send);
1340
1341/**
1342 * iucv_message_send2way
1343 * @path: address of iucv path structure
1344 * @msg: address of iucv msg structure
1345 * @flags: how the message is sent and the reply is received
1346 *         (IUCV_IPRMDATA, IUCV_IPBUFLST, IUCV_IPPRTY, IUCV_ANSLST)
1347 * @srccls: source class of message
1348 * @buffer: address of send buffer or address of struct iucv_array
1349 * @size: length of send buffer
1350 * @answer: address of answer buffer or address of struct iucv_array
1351 * @asize: size of reply buffer
1352 * @residual: ignored
1353 *
1354 * This function transmits data to another application. Data to be
1355 * transmitted is in a buffer. The receiver of the send is expected to
1356 * reply to the message and a buffer is provided into which IUCV moves
1357 * the reply to this message.
1358 *
1359 * Returns the result from the CP IUCV call.
1360 */
1361int iucv_message_send2way(struct iucv_path *path, struct iucv_message *msg,
1362                          u8 flags, u32 srccls, void *buffer, size_t size,
1363                          void *answer, size_t asize, size_t *residual)
1364{
1365        union iucv_param *parm;
1366        int rc;
1367
1368        local_bh_disable();
1369        if (cpumask_empty(&iucv_buffer_cpumask)) {
1370                rc = -EIO;
1371                goto out;
1372        }
1373        parm = iucv_param[smp_processor_id()];
1374        memset(parm, 0, sizeof(union iucv_param));
1375        if (flags & IUCV_IPRMDATA) {
1376                parm->dpl.ippathid = path->pathid;
1377                parm->dpl.ipflags1 = path->flags;       /* priority message */
1378                parm->dpl.iptrgcls = msg->class;
1379                parm->dpl.ipsrccls = srccls;
1380                parm->dpl.ipmsgtag = msg->tag;
1381                parm->dpl.ipbfadr2 = (u32)(addr_t) answer;
1382                parm->dpl.ipbfln2f = (u32) asize;
1383                memcpy(parm->dpl.iprmmsg, buffer, 8);
1384        } else {
1385                parm->db.ippathid = path->pathid;
1386                parm->db.ipflags1 = path->flags;        /* priority message */
1387                parm->db.iptrgcls = msg->class;
1388                parm->db.ipsrccls = srccls;
1389                parm->db.ipmsgtag = msg->tag;
1390                parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1391                parm->db.ipbfln1f = (u32) size;
1392                parm->db.ipbfadr2 = (u32)(addr_t) answer;
1393                parm->db.ipbfln2f = (u32) asize;
1394        }
1395        rc = iucv_call_b2f0(IUCV_SEND, parm);
1396        if (!rc)
1397                msg->id = parm->db.ipmsgid;
1398out:
1399        local_bh_enable();
1400        return rc;
1401}
1402EXPORT_SYMBOL(iucv_message_send2way);
1403
1404struct iucv_path_pending {
1405        u16 ippathid;
1406        u8  ipflags1;
1407        u8  iptype;
1408        u16 ipmsglim;
1409        u16 res1;
1410        u8  ipvmid[8];
1411        u8  ipuser[16];
1412        u32 res3;
1413        u8  ippollfg;
1414        u8  res4[3];
1415} __packed;
1416
1417/**
1418 * iucv_path_pending
1419 * @data: Pointer to external interrupt buffer
1420 *
1421 * Process connection pending work item. Called from tasklet while holding
1422 * iucv_table_lock.
1423 */
1424static void iucv_path_pending(struct iucv_irq_data *data)
1425{
1426        struct iucv_path_pending *ipp = (void *) data;
1427        struct iucv_handler *handler;
1428        struct iucv_path *path;
1429        char *error;
1430
1431        BUG_ON(iucv_path_table[ipp->ippathid]);
1432        /* New pathid, handler found. Create a new path struct. */
1433        error = iucv_error_no_memory;
1434        path = iucv_path_alloc(ipp->ipmsglim, ipp->ipflags1, GFP_ATOMIC);
1435        if (!path)
1436                goto out_sever;
1437        path->pathid = ipp->ippathid;
1438        iucv_path_table[path->pathid] = path;
1439        EBCASC(ipp->ipvmid, 8);
1440
1441        /* Call registered handler until one is found that wants the path. */
1442        list_for_each_entry(handler, &iucv_handler_list, list) {
1443                if (!handler->path_pending)
1444                        continue;
1445                /*
1446                 * Add path to handler to allow a call to iucv_path_sever
1447                 * inside the path_pending function. If the handler returns
1448                 * an error remove the path from the handler again.
1449                 */
1450                list_add(&path->list, &handler->paths);
1451                path->handler = handler;
1452                if (!handler->path_pending(path, ipp->ipvmid, ipp->ipuser))
1453                        return;
1454                list_del(&path->list);
1455                path->handler = NULL;
1456        }
1457        /* No handler wanted the path. */
1458        iucv_path_table[path->pathid] = NULL;
1459        iucv_path_free(path);
1460        error = iucv_error_no_listener;
1461out_sever:
1462        iucv_sever_pathid(ipp->ippathid, error);
1463}
1464
1465struct iucv_path_complete {
1466        u16 ippathid;
1467        u8  ipflags1;
1468        u8  iptype;
1469        u16 ipmsglim;
1470        u16 res1;
1471        u8  res2[8];
1472        u8  ipuser[16];
1473        u32 res3;
1474        u8  ippollfg;
1475        u8  res4[3];
1476} __packed;
1477
1478/**
1479 * iucv_path_complete
1480 * @data: Pointer to external interrupt buffer
1481 *
1482 * Process connection complete work item. Called from tasklet while holding
1483 * iucv_table_lock.
1484 */
1485static void iucv_path_complete(struct iucv_irq_data *data)
1486{
1487        struct iucv_path_complete *ipc = (void *) data;
1488        struct iucv_path *path = iucv_path_table[ipc->ippathid];
1489
1490        if (path)
1491                path->flags = ipc->ipflags1;
1492        if (path && path->handler && path->handler->path_complete)
1493                path->handler->path_complete(path, ipc->ipuser);
1494}
1495
1496struct iucv_path_severed {
1497        u16 ippathid;
1498        u8  res1;
1499        u8  iptype;
1500        u32 res2;
1501        u8  res3[8];
1502        u8  ipuser[16];
1503        u32 res4;
1504        u8  ippollfg;
1505        u8  res5[3];
1506} __packed;
1507
1508/**
1509 * iucv_path_severed
1510 * @data: Pointer to external interrupt buffer
1511 *
1512 * Process connection severed work item. Called from tasklet while holding
1513 * iucv_table_lock.
1514 */
1515static void iucv_path_severed(struct iucv_irq_data *data)
1516{
1517        struct iucv_path_severed *ips = (void *) data;
1518        struct iucv_path *path = iucv_path_table[ips->ippathid];
1519
1520        if (!path || !path->handler)    /* Already severed */
1521                return;
1522        if (path->handler->path_severed)
1523                path->handler->path_severed(path, ips->ipuser);
1524        else {
1525                iucv_sever_pathid(path->pathid, NULL);
1526                iucv_path_table[path->pathid] = NULL;
1527                list_del(&path->list);
1528                iucv_path_free(path);
1529        }
1530}
1531
1532struct iucv_path_quiesced {
1533        u16 ippathid;
1534        u8  res1;
1535        u8  iptype;
1536        u32 res2;
1537        u8  res3[8];
1538        u8  ipuser[16];
1539        u32 res4;
1540        u8  ippollfg;
1541        u8  res5[3];
1542} __packed;
1543
1544/**
1545 * iucv_path_quiesced
1546 * @data: Pointer to external interrupt buffer
1547 *
1548 * Process connection quiesced work item. Called from tasklet while holding
1549 * iucv_table_lock.
1550 */
1551static void iucv_path_quiesced(struct iucv_irq_data *data)
1552{
1553        struct iucv_path_quiesced *ipq = (void *) data;
1554        struct iucv_path *path = iucv_path_table[ipq->ippathid];
1555
1556        if (path && path->handler && path->handler->path_quiesced)
1557                path->handler->path_quiesced(path, ipq->ipuser);
1558}
1559
1560struct iucv_path_resumed {
1561        u16 ippathid;
1562        u8  res1;
1563        u8  iptype;
1564        u32 res2;
1565        u8  res3[8];
1566        u8  ipuser[16];
1567        u32 res4;
1568        u8  ippollfg;
1569        u8  res5[3];
1570} __packed;
1571
1572/**
1573 * iucv_path_resumed
1574 * @data: Pointer to external interrupt buffer
1575 *
1576 * Process connection resumed work item. Called from tasklet while holding
1577 * iucv_table_lock.
1578 */
1579static void iucv_path_resumed(struct iucv_irq_data *data)
1580{
1581        struct iucv_path_resumed *ipr = (void *) data;
1582        struct iucv_path *path = iucv_path_table[ipr->ippathid];
1583
1584        if (path && path->handler && path->handler->path_resumed)
1585                path->handler->path_resumed(path, ipr->ipuser);
1586}
1587
1588struct iucv_message_complete {
1589        u16 ippathid;
1590        u8  ipflags1;
1591        u8  iptype;
1592        u32 ipmsgid;
1593        u32 ipaudit;
1594        u8  iprmmsg[8];
1595        u32 ipsrccls;
1596        u32 ipmsgtag;
1597        u32 res;
1598        u32 ipbfln2f;
1599        u8  ippollfg;
1600        u8  res2[3];
1601} __packed;
1602
1603/**
1604 * iucv_message_complete
1605 * @data: Pointer to external interrupt buffer
1606 *
1607 * Process message complete work item. Called from tasklet while holding
1608 * iucv_table_lock.
1609 */
1610static void iucv_message_complete(struct iucv_irq_data *data)
1611{
1612        struct iucv_message_complete *imc = (void *) data;
1613        struct iucv_path *path = iucv_path_table[imc->ippathid];
1614        struct iucv_message msg;
1615
1616        if (path && path->handler && path->handler->message_complete) {
1617                msg.flags = imc->ipflags1;
1618                msg.id = imc->ipmsgid;
1619                msg.audit = imc->ipaudit;
1620                memcpy(msg.rmmsg, imc->iprmmsg, 8);
1621                msg.class = imc->ipsrccls;
1622                msg.tag = imc->ipmsgtag;
1623                msg.length = imc->ipbfln2f;
1624                path->handler->message_complete(path, &msg);
1625        }
1626}
1627
1628struct iucv_message_pending {
1629        u16 ippathid;
1630        u8  ipflags1;
1631        u8  iptype;
1632        u32 ipmsgid;
1633        u32 iptrgcls;
1634        struct {
1635                union {
1636                        u32 iprmmsg1_u32;
1637                        u8  iprmmsg1[4];
1638                } ln1msg1;
1639                union {
1640                        u32 ipbfln1f;
1641                        u8  iprmmsg2[4];
1642                } ln1msg2;
1643        } rmmsg;
1644        u32 res1[3];
1645        u32 ipbfln2f;
1646        u8  ippollfg;
1647        u8  res2[3];
1648} __packed;
1649
1650/**
1651 * iucv_message_pending
1652 * @data: Pointer to external interrupt buffer
1653 *
1654 * Process message pending work item. Called from tasklet while holding
1655 * iucv_table_lock.
1656 */
1657static void iucv_message_pending(struct iucv_irq_data *data)
1658{
1659        struct iucv_message_pending *imp = (void *) data;
1660        struct iucv_path *path = iucv_path_table[imp->ippathid];
1661        struct iucv_message msg;
1662
1663        if (path && path->handler && path->handler->message_pending) {
1664                msg.flags = imp->ipflags1;
1665                msg.id = imp->ipmsgid;
1666                msg.class = imp->iptrgcls;
1667                if (imp->ipflags1 & IUCV_IPRMDATA) {
1668                        memcpy(msg.rmmsg, &imp->rmmsg, 8);
1669                        msg.length = 8;
1670                } else
1671                        msg.length = imp->rmmsg.ln1msg2.ipbfln1f;
1672                msg.reply_size = imp->ipbfln2f;
1673                path->handler->message_pending(path, &msg);
1674        }
1675}
1676
1677/*
1678 * iucv_tasklet_fn:
1679 *
1680 * This tasklet loops over the queue of irq buffers created by
1681 * iucv_external_interrupt, calls the appropriate action handler
1682 * and then frees the buffer.
1683 */
1684static void iucv_tasklet_fn(unsigned long ignored)
1685{
1686        typedef void iucv_irq_fn(struct iucv_irq_data *);
1687        static iucv_irq_fn *irq_fn[] = {
1688                [0x02] = iucv_path_complete,
1689                [0x03] = iucv_path_severed,
1690                [0x04] = iucv_path_quiesced,
1691                [0x05] = iucv_path_resumed,
1692                [0x06] = iucv_message_complete,
1693                [0x07] = iucv_message_complete,
1694                [0x08] = iucv_message_pending,
1695                [0x09] = iucv_message_pending,
1696        };
1697        LIST_HEAD(task_queue);
1698        struct iucv_irq_list *p, *n;
1699
1700        /* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1701        if (!spin_trylock(&iucv_table_lock)) {
1702                tasklet_schedule(&iucv_tasklet);
1703                return;
1704        }
1705        iucv_active_cpu = smp_processor_id();
1706
1707        spin_lock_irq(&iucv_queue_lock);
1708        list_splice_init(&iucv_task_queue, &task_queue);
1709        spin_unlock_irq(&iucv_queue_lock);
1710
1711        list_for_each_entry_safe(p, n, &task_queue, list) {
1712                list_del_init(&p->list);
1713                irq_fn[p->data.iptype](&p->data);
1714                kfree(p);
1715        }
1716
1717        iucv_active_cpu = -1;
1718        spin_unlock(&iucv_table_lock);
1719}
1720
1721/*
1722 * iucv_work_fn:
1723 *
1724 * This work function loops over the queue of path pending irq blocks
1725 * created by iucv_external_interrupt, calls the appropriate action
1726 * handler and then frees the buffer.
1727 */
1728static void iucv_work_fn(struct work_struct *work)
1729{
1730        LIST_HEAD(work_queue);
1731        struct iucv_irq_list *p, *n;
1732
1733        /* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1734        spin_lock_bh(&iucv_table_lock);
1735        iucv_active_cpu = smp_processor_id();
1736
1737        spin_lock_irq(&iucv_queue_lock);
1738        list_splice_init(&iucv_work_queue, &work_queue);
1739        spin_unlock_irq(&iucv_queue_lock);
1740
1741        iucv_cleanup_queue();
1742        list_for_each_entry_safe(p, n, &work_queue, list) {
1743                list_del_init(&p->list);
1744                iucv_path_pending(&p->data);
1745                kfree(p);
1746        }
1747
1748        iucv_active_cpu = -1;
1749        spin_unlock_bh(&iucv_table_lock);
1750}
1751
1752/*
1753 * iucv_external_interrupt
1754 *
1755 * Handles external interrupts coming in from CP.
1756 * Places the interrupt buffer on a queue and schedules iucv_tasklet_fn().
1757 */
1758static void iucv_external_interrupt(struct ext_code ext_code,
1759                                    unsigned int param32, unsigned long param64)
1760{
1761        struct iucv_irq_data *p;
1762        struct iucv_irq_list *work;
1763
1764        inc_irq_stat(IRQEXT_IUC);
1765        p = iucv_irq_data[smp_processor_id()];
1766        if (p->ippathid >= iucv_max_pathid) {
1767                WARN_ON(p->ippathid >= iucv_max_pathid);
1768                iucv_sever_pathid(p->ippathid, iucv_error_no_listener);
1769                return;
1770        }
1771        BUG_ON(p->iptype  < 0x01 || p->iptype > 0x09);
1772        work = kmalloc(sizeof(struct iucv_irq_list), GFP_ATOMIC);
1773        if (!work) {
1774                pr_warn("iucv_external_interrupt: out of memory\n");
1775                return;
1776        }
1777        memcpy(&work->data, p, sizeof(work->data));
1778        spin_lock(&iucv_queue_lock);
1779        if (p->iptype == 0x01) {
1780                /* Path pending interrupt. */
1781                list_add_tail(&work->list, &iucv_work_queue);
1782                schedule_work(&iucv_work);
1783        } else {
1784                /* The other interrupts. */
1785                list_add_tail(&work->list, &iucv_task_queue);
1786                tasklet_schedule(&iucv_tasklet);
1787        }
1788        spin_unlock(&iucv_queue_lock);
1789}
1790
1791struct iucv_interface iucv_if = {
1792        .message_receive = iucv_message_receive,
1793        .__message_receive = __iucv_message_receive,
1794        .message_reply = iucv_message_reply,
1795        .message_reject = iucv_message_reject,
1796        .message_send = iucv_message_send,
1797        .__message_send = __iucv_message_send,
1798        .message_send2way = iucv_message_send2way,
1799        .message_purge = iucv_message_purge,
1800        .path_accept = iucv_path_accept,
1801        .path_connect = iucv_path_connect,
1802        .path_quiesce = iucv_path_quiesce,
1803        .path_resume = iucv_path_resume,
1804        .path_sever = iucv_path_sever,
1805        .iucv_register = iucv_register,
1806        .iucv_unregister = iucv_unregister,
1807        .bus = NULL,
1808        .root = NULL,
1809};
1810EXPORT_SYMBOL(iucv_if);
1811
1812static enum cpuhp_state iucv_online;
1813/**
1814 * iucv_init
1815 *
1816 * Allocates and initializes various data structures.
1817 */
1818static int __init iucv_init(void)
1819{
1820        int rc;
1821
1822        if (!MACHINE_IS_VM) {
1823                rc = -EPROTONOSUPPORT;
1824                goto out;
1825        }
1826        ctl_set_bit(0, 1);
1827        rc = iucv_query_maxconn();
1828        if (rc)
1829                goto out_ctl;
1830        rc = register_external_irq(EXT_IRQ_IUCV, iucv_external_interrupt);
1831        if (rc)
1832                goto out_ctl;
1833        iucv_root = root_device_register("iucv");
1834        if (IS_ERR(iucv_root)) {
1835                rc = PTR_ERR(iucv_root);
1836                goto out_int;
1837        }
1838
1839        rc = cpuhp_setup_state(CPUHP_NET_IUCV_PREPARE, "net/iucv:prepare",
1840                               iucv_cpu_prepare, iucv_cpu_dead);
1841        if (rc)
1842                goto out_dev;
1843        rc = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "net/iucv:online",
1844                               iucv_cpu_online, iucv_cpu_down_prep);
1845        if (rc < 0)
1846                goto out_prep;
1847        iucv_online = rc;
1848
1849        rc = register_reboot_notifier(&iucv_reboot_notifier);
1850        if (rc)
1851                goto out_remove_hp;
1852        ASCEBC(iucv_error_no_listener, 16);
1853        ASCEBC(iucv_error_no_memory, 16);
1854        ASCEBC(iucv_error_pathid, 16);
1855        iucv_available = 1;
1856        rc = bus_register(&iucv_bus);
1857        if (rc)
1858                goto out_reboot;
1859        iucv_if.root = iucv_root;
1860        iucv_if.bus = &iucv_bus;
1861        return 0;
1862
1863out_reboot:
1864        unregister_reboot_notifier(&iucv_reboot_notifier);
1865out_remove_hp:
1866        cpuhp_remove_state(iucv_online);
1867out_prep:
1868        cpuhp_remove_state(CPUHP_NET_IUCV_PREPARE);
1869out_dev:
1870        root_device_unregister(iucv_root);
1871out_int:
1872        unregister_external_irq(EXT_IRQ_IUCV, iucv_external_interrupt);
1873out_ctl:
1874        ctl_clear_bit(0, 1);
1875out:
1876        return rc;
1877}
1878
1879/**
1880 * iucv_exit
1881 *
1882 * Frees everything allocated from iucv_init.
1883 */
1884static void __exit iucv_exit(void)
1885{
1886        struct iucv_irq_list *p, *n;
1887
1888        spin_lock_irq(&iucv_queue_lock);
1889        list_for_each_entry_safe(p, n, &iucv_task_queue, list)
1890                kfree(p);
1891        list_for_each_entry_safe(p, n, &iucv_work_queue, list)
1892                kfree(p);
1893        spin_unlock_irq(&iucv_queue_lock);
1894        unregister_reboot_notifier(&iucv_reboot_notifier);
1895
1896        cpuhp_remove_state_nocalls(iucv_online);
1897        cpuhp_remove_state(CPUHP_NET_IUCV_PREPARE);
1898        root_device_unregister(iucv_root);
1899        bus_unregister(&iucv_bus);
1900        unregister_external_irq(EXT_IRQ_IUCV, iucv_external_interrupt);
1901}
1902
1903subsys_initcall(iucv_init);
1904module_exit(iucv_exit);
1905
1906MODULE_AUTHOR("(C) 2001 IBM Corp. by Fritz Elfert (felfert@millenux.com)");
1907MODULE_DESCRIPTION("Linux for S/390 IUCV lowlevel driver");
1908MODULE_LICENSE("GPL");
1909