net/iucv/iucv.c

   1 /*
   2  * IUCV base infrastructure.
   3  *
   4  * Copyright 2001, 2006 IBM Deutschland Entwicklung GmbH, IBM Corporation
   5  * Author(s):
   6  *    Original source:
   7  *      Alan Altmark (Alan_Altmark@us.ibm.com)  Sept. 2000
   8  *      Xenia Tkatschow (xenia@us.ibm.com)
   9  *    2Gb awareness and general cleanup:
  10  *      Fritz Elfert (elfert@de.ibm.com, felfert@millenux.com)
  11  *    Rewritten for af_iucv:
  12  *      Martin Schwidefsky <schwidefsky@de.ibm.com>
  13  *
  14  * Documentation used:
  15  *    The original source
  16  *    CP Programming Service, IBM document # SC24-5760
  17  *
  18  * This program is free software; you can redistribute it and/or modify
  19  * it under the terms of the GNU General Public License as published by
  20  * the Free Software Foundation; either version 2, or (at your option)
  21  * any later version.
  22  *
  23  * This program is distributed in the hope that it will be useful,
  24  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  26  * GNU General Public License for more details.
  27  *
  28  * You should have received a copy of the GNU General Public License
  29  * along with this program; if not, write to the Free Software
  30  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  31  */
  32
  33 #include <linux/module.h>
  34 #include <linux/moduleparam.h>
  35
  36 #include <linux/spinlock.h>
  37 #include <linux/kernel.h>
  38 #include <linux/slab.h>
  39 #include <linux/init.h>
  40 #include <linux/interrupt.h>
  41 #include <linux/list.h>
  42 #include <linux/errno.h>
  43 #include <linux/err.h>
  44 #include <linux/device.h>
  45 #include <linux/cpu.h>
  46 #include <net/iucv/iucv.h>
  47 #include <asm/atomic.h>
  48 #include <asm/ebcdic.h>
  49 #include <asm/io.h>
  50 #include <asm/s390_ext.h>
  51 #include <asm/s390_rdev.h>
  52 #include <asm/smp.h>
  53
  54 /*
  55  * FLAGS:
  56  * All flags are defined in the field IPFLAGS1 of each function
  57  * and can be found in CP Programming Services.
  58  * IPSRCCLS - Indicates you have specified a source class.
  59  * IPTRGCLS - Indicates you have specified a target class.
  60  * IPFGPID  - Indicates you have specified a pathid.
  61  * IPFGMID  - Indicates you have specified a message ID.
  62  * IPNORPY  - Indicates a one-way message. No reply expected.
  63  * IPALL    - Indicates that all paths are affected.
  64  */
  65 #define IUCV_IPSRCCLS   0x01
  66 #define IUCV_IPTRGCLS   0x01
  67 #define IUCV_IPFGPID    0x02
  68 #define IUCV_IPFGMID    0x04
  69 #define IUCV_IPNORPY    0x10
  70 #define IUCV_IPALL      0x80
  71
  72 static int iucv_bus_match (struct device *dev, struct device_driver *drv)
  73 {
  74         return 0;
  75 }
  76
  77 struct bus_type iucv_bus = {
  78         .name = "iucv",
  79         .match = iucv_bus_match,
  80 };
  81
  82 struct device *iucv_root;
  83 static int iucv_available;
  84
  85 /* General IUCV interrupt structure */
  86 struct iucv_irq_data {
  87         u16 ippathid;
  88         u8  ipflags1;
  89         u8  iptype;
  90         u32 res2[8];
  91 };
  92
  93 struct iucv_work {
  94         struct list_head list;
  95         struct iucv_irq_data data;
  96 };
  97
  98 static LIST_HEAD(iucv_work_queue);
  99 static DEFINE_SPINLOCK(iucv_work_lock);
 100
 101 static struct iucv_irq_data *iucv_irq_data;
 102 static cpumask_t iucv_buffer_cpumask = CPU_MASK_NONE;
 103 static cpumask_t iucv_irq_cpumask = CPU_MASK_NONE;
 104
 105 static void iucv_tasklet_handler(unsigned long);
 106 static DECLARE_TASKLET(iucv_tasklet, iucv_tasklet_handler,0);
 107
 108 enum iucv_command_codes {
 109         IUCV_QUERY = 0,
 110         IUCV_RETRIEVE_BUFFER = 2,
 111         IUCV_SEND = 4,
 112         IUCV_RECEIVE = 5,
 113         IUCV_REPLY = 6,
 114         IUCV_REJECT = 8,
 115         IUCV_PURGE = 9,
 116         IUCV_ACCEPT = 10,
 117         IUCV_CONNECT = 11,
 118         IUCV_DECLARE_BUFFER = 12,
 119         IUCV_QUIESCE = 13,
 120         IUCV_RESUME = 14,
 121         IUCV_SEVER = 15,
 122         IUCV_SETMASK = 16,
 123 };
 124
 125 /*
 126  * Error messages that are used with the iucv_sever function. They get
 127  * converted to EBCDIC.
 128  */
 129 static char iucv_error_no_listener[16] = "NO LISTENER";
 130 static char iucv_error_no_memory[16] = "NO MEMORY";
 131 static char iucv_error_pathid[16] = "INVALID PATHID";
 132
 133 /*
 134  * iucv_handler_list: List of registered handlers.
 135  */
 136 static LIST_HEAD(iucv_handler_list);
 137
 138 /*
 139  * iucv_path_table: an array of iucv_path structures.
 140  */
 141 static struct iucv_path **iucv_path_table;
 142 static unsigned long iucv_max_pathid;
 143
 144 /*
 145  * iucv_lock: spinlock protecting iucv_handler_list and iucv_pathid_table
 146  */
 147 static DEFINE_SPINLOCK(iucv_table_lock);
 148
 149 /*
 150  * iucv_tasklet_cpu: contains the number of the cpu executing the tasklet.
 151  * Needed for iucv_path_sever called from tasklet.
 152  */
 153 static int iucv_tasklet_cpu = -1;
 154
 155 /*
 156  * Mutex and wait queue for iucv_register/iucv_unregister.
 157  */
 158 static DEFINE_MUTEX(iucv_register_mutex);
 159
 160 /*
 161  * Counter for number of non-smp capable handlers.
 162  */
 163 static int iucv_nonsmp_handler;
 164
 165 /*
 166  * IUCV control data structure. Used by iucv_path_accept, iucv_path_connect,
 167  * iucv_path_quiesce and iucv_path_sever.
 168  */
 169 struct iucv_cmd_control {
 170         u16 ippathid;
 171         u8  ipflags1;
 172         u8  iprcode;
 173         u16 ipmsglim;
 174         u16 res1;
 175         u8  ipvmid[8];
 176         u8  ipuser[16];
 177         u8  iptarget[8];
 178 } __attribute__ ((packed,aligned(8)));
 179
 180 /*
 181  * Data in parameter list iucv structure. Used by iucv_message_send,
 182  * iucv_message_send2way and iucv_message_reply.
 183  */
 184 struct iucv_cmd_dpl {
 185         u16 ippathid;
 186         u8  ipflags1;
 187         u8  iprcode;
 188         u32 ipmsgid;
 189         u32 iptrgcls;
 190         u8  iprmmsg[8];
 191         u32 ipsrccls;
 192         u32 ipmsgtag;
 193         u32 ipbfadr2;
 194         u32 ipbfln2f;
 195         u32 res;
 196 } __attribute__ ((packed,aligned(8)));
 197
 198 /*
 199  * Data in buffer iucv structure. Used by iucv_message_receive,
 200  * iucv_message_reject, iucv_message_send, iucv_message_send2way
 201  * and iucv_declare_cpu.
 202  */
 203 struct iucv_cmd_db {
 204         u16 ippathid;
 205         u8  ipflags1;
 206         u8  iprcode;
 207         u32 ipmsgid;
 208         u32 iptrgcls;
 209         u32 ipbfadr1;
 210         u32 ipbfln1f;
 211         u32 ipsrccls;
 212         u32 ipmsgtag;
 213         u32 ipbfadr2;
 214         u32 ipbfln2f;
 215         u32 res;
 216 } __attribute__ ((packed,aligned(8)));
 217
 218 /*
 219  * Purge message iucv structure. Used by iucv_message_purge.
 220  */
 221 struct iucv_cmd_purge {
 222         u16 ippathid;
 223         u8  ipflags1;
 224         u8  iprcode;
 225         u32 ipmsgid;
 226         u8  ipaudit[3];
 227         u8  res1[5];
 228         u32 res2;
 229         u32 ipsrccls;
 230         u32 ipmsgtag;
 231         u32 res3[3];
 232 } __attribute__ ((packed,aligned(8)));
 233
 234 /*
 235  * Set mask iucv structure. Used by iucv_enable_cpu.
 236  */
 237 struct iucv_cmd_set_mask {
 238         u8  ipmask;
 239         u8  res1[2];
 240         u8  iprcode;
 241         u32 res2[9];
 242 } __attribute__ ((packed,aligned(8)));
 243
 244 union iucv_param {
 245         struct iucv_cmd_control ctrl;
 246         struct iucv_cmd_dpl dpl;
 247         struct iucv_cmd_db db;
 248         struct iucv_cmd_purge purge;
 249         struct iucv_cmd_set_mask set_mask;
 250 };
 251
 252 /*
 253  * Anchor for per-cpu IUCV command parameter block.
 254  */
 255 static union iucv_param *iucv_param;
 256
 257 /**
 258  * iucv_call_b2f0
 259  * @code: identifier of IUCV call to CP.
 260  * @parm: pointer to a struct iucv_parm block
 261  *
 262  * Calls CP to execute IUCV commands.
 263  *
 264  * Returns the result of the CP IUCV call.
 265  */
 266 static inline int iucv_call_b2f0(int command, union iucv_param *parm)
 267 {
 268         register unsigned long reg0 asm ("0");
 269         register unsigned long reg1 asm ("1");
 270         int ccode;
 271
 272         reg0 = command;
 273         reg1 = virt_to_phys(parm);
 274         asm volatile(
 275                 "       .long 0xb2f01000\n"
 276                 "       ipm     %0\n"
 277                 "       srl     %0,28\n"
 278                 : "=d" (ccode), "=m" (*parm), "+d" (reg0), "+a" (reg1)
 279                 :  "m" (*parm) : "cc");
 280         return (ccode == 1) ? parm->ctrl.iprcode : ccode;
 281 }
 282
 283 /**
 284  * iucv_query_maxconn
 285  *
 286  * Determines the maximum number of connections that may be established.
 287  *
 288  * Returns the maximum number of connections or -EPERM is IUCV is not
 289  * available.
 290  */
 291 static int iucv_query_maxconn(void)
 292 {
 293         register unsigned long reg0 asm ("0");
 294         register unsigned long reg1 asm ("1");
 295         void *param;
 296         int ccode;
 297
 298         param = kzalloc(sizeof(union iucv_param), GFP_KERNEL|GFP_DMA);
 299         if (!param)
 300                 return -ENOMEM;
 301         reg0 = IUCV_QUERY;
 302         reg1 = (unsigned long) param;
 303         asm volatile (
 304                 "       .long   0xb2f01000\n"
 305                 "       ipm     %0\n"
 306                 "       srl     %0,28\n"
 307                 : "=d" (ccode), "+d" (reg0), "+d" (reg1) : : "cc");
 308         if (ccode == 0)
 309                 iucv_max_pathid = reg0;
 310         kfree(param);
 311         return ccode ? -EPERM : 0;
 312 }
 313
 314 /**
 315  * iucv_allow_cpu
 316  * @data: unused
 317  *
 318  * Allow iucv interrupts on this cpu.
 319  */
 320 static void iucv_allow_cpu(void *data)
 321 {
 322         int cpu = smp_processor_id();
 323         union iucv_param *parm;
 324
 325         /*
 326          * Enable all iucv interrupts.
 327          * ipmask contains bits for the different interrupts
 328          *      0x80 - Flag to allow nonpriority message pending interrupts
 329          *      0x40 - Flag to allow priority message pending interrupts
 330          *      0x20 - Flag to allow nonpriority message completion interrupts
 331          *      0x10 - Flag to allow priority message completion interrupts
 332          *      0x08 - Flag to allow IUCV control interrupts
 333          */
 334         parm = percpu_ptr(iucv_param, smp_processor_id());
 335         memset(parm, 0, sizeof(union iucv_param));
 336         parm->set_mask.ipmask = 0xf8;
 337         iucv_call_b2f0(IUCV_SETMASK, parm);
 338
 339         /* Set indication that iucv interrupts are allowed for this cpu. */
 340         cpu_set(cpu, iucv_irq_cpumask);
 341 }
 342
 343 /**
 344  * iucv_block_cpu
 345  * @data: unused
 346  *
 347  * Block iucv interrupts on this cpu.
 348  */
 349 static void iucv_block_cpu(void *data)
 350 {
 351         int cpu = smp_processor_id();
 352         union iucv_param *parm;
 353
 354         /* Disable all iucv interrupts. */
 355         parm = percpu_ptr(iucv_param, smp_processor_id());
 356         memset(parm, 0, sizeof(union iucv_param));
 357         iucv_call_b2f0(IUCV_SETMASK, parm);
 358
 359         /* Clear indication that iucv interrupts are allowed for this cpu. */
 360         cpu_clear(cpu, iucv_irq_cpumask);
 361 }
 362
 363 /**
 364  * iucv_declare_cpu
 365  * @data: unused
 366  *
 367  * Declare a interupt buffer on this cpu.
 368  */
 369 static void iucv_declare_cpu(void *data)
 370 {
 371         int cpu = smp_processor_id();
 372         union iucv_param *parm;
 373         int rc;
 374
 375         if (cpu_isset(cpu, iucv_buffer_cpumask))
 376                 return;
 377
 378         /* Declare interrupt buffer. */
 379         parm = percpu_ptr(iucv_param, cpu);
 380         memset(parm, 0, sizeof(union iucv_param));
 381         parm->db.ipbfadr1 = virt_to_phys(percpu_ptr(iucv_irq_data, cpu));
 382         rc = iucv_call_b2f0(IUCV_DECLARE_BUFFER, parm);
 383         if (rc) {
 384                 char *err = "Unknown";
 385                 switch(rc) {
 386                 case 0x03:
 387                         err = "Directory error";
 388                         break;
 389                 case 0x0a:
 390                         err = "Invalid length";
 391                         break;
 392                 case 0x13:
 393                         err = "Buffer already exists";
 394                         break;
 395                 case 0x3e:
 396                         err = "Buffer overlap";
 397                         break;
 398                 case 0x5c:
 399                         err = "Paging or storage error";
 400                         break;
 401                 }
 402                 printk(KERN_WARNING "iucv_register: iucv_declare_buffer "
 403                        "on cpu %i returned error 0x%02x (%s)\n", cpu, rc, err);
 404                 return;
 405         }
 406
 407         /* Set indication that an iucv buffer exists for this cpu. */
 408         cpu_set(cpu, iucv_buffer_cpumask);
 409
 410         if (iucv_nonsmp_handler == 0 || cpus_empty(iucv_irq_cpumask))
 411                 /* Enable iucv interrupts on this cpu. */
 412                 iucv_allow_cpu(NULL);
 413         else
 414                 /* Disable iucv interrupts on this cpu. */
 415                 iucv_block_cpu(NULL);
 416 }
 417
 418 /**
 419  * iucv_retrieve_cpu
 420  * @data: unused
 421  *
 422  * Retrieve interrupt buffer on this cpu.
 423  */
 424 static void iucv_retrieve_cpu(void *data)
 425 {
 426         int cpu = smp_processor_id();
 427         union iucv_param *parm;
 428
 429         if (!cpu_isset(cpu, iucv_buffer_cpumask))
 430                 return;
 431
 432         /* Block iucv interrupts. */
 433         iucv_block_cpu(NULL);
 434
 435         /* Retrieve interrupt buffer. */
 436         parm = percpu_ptr(iucv_param, cpu);
 437         iucv_call_b2f0(IUCV_RETRIEVE_BUFFER, parm);
 438
 439         /* Clear indication that an iucv buffer exists for this cpu. */
 440         cpu_clear(cpu, iucv_buffer_cpumask);
 441 }
 442
 443 /**
 444  * iucv_setmask_smp
 445  *
 446  * Allow iucv interrupts on all cpus.
 447  */
 448 static void iucv_setmask_mp(void)
 449 {
 450         int cpu;
 451
 452         for_each_online_cpu(cpu)
 453                 /* Enable all cpus with a declared buffer. */
 454                 if (cpu_isset(cpu, iucv_buffer_cpumask) &&
 455                     !cpu_isset(cpu, iucv_irq_cpumask))
 456                         smp_call_function_on(iucv_allow_cpu, NULL, 0, 1, cpu);
 457 }
 458
 459 /**
 460  * iucv_setmask_up
 461  *
 462  * Allow iucv interrupts on a single cpus.
 463  */
 464 static void iucv_setmask_up(void)
 465 {
 466         cpumask_t cpumask;
 467         int cpu;
 468
 469         /* Disable all cpu but the first in cpu_irq_cpumask. */
 470         cpumask = iucv_irq_cpumask;
 471         cpu_clear(first_cpu(iucv_irq_cpumask), cpumask);
 472         for_each_cpu_mask(cpu, cpumask)
 473                 smp_call_function_on(iucv_block_cpu, NULL, 0, 1, cpu);
 474 }
 475
 476 /**
 477  * iucv_enable
 478  *
 479  * This function makes iucv ready for use. It allocates the pathid
 480  * table, declares an iucv interrupt buffer and enables the iucv
 481  * interrupts. Called when the first user has registered an iucv
 482  * handler.
 483  */
 484 static int iucv_enable(void)
 485 {
 486         size_t alloc_size;
 487         int cpu, rc;
 488
 489         rc = -ENOMEM;
 490         alloc_size = iucv_max_pathid * sizeof(struct iucv_path);
 491         iucv_path_table = kzalloc(alloc_size, GFP_KERNEL);
 492         if (!iucv_path_table)
 493                 goto out;
 494         /* Declare per cpu buffers. */
 495         rc = -EIO;
 496         for_each_online_cpu(cpu)
 497                 smp_call_function_on(iucv_declare_cpu, NULL, 0, 1, cpu);
 498         if (cpus_empty(iucv_buffer_cpumask))
 499                 /* No cpu could declare an iucv buffer. */
 500                 goto out_path;
 501         return 0;
 502
 503 out_path:
 504         kfree(iucv_path_table);
 505 out:
 506         return rc;
 507 }
 508
 509 /**
 510  * iucv_disable
 511  *
 512  * This function shuts down iucv. It disables iucv interrupts, retrieves
 513  * the iucv interrupt buffer and frees the pathid table. Called after the
 514  * last user unregister its iucv handler.
 515  */
 516 static void iucv_disable(void)
 517 {
 518         on_each_cpu(iucv_retrieve_cpu, NULL, 0, 1);
 519         kfree(iucv_path_table);
 520 }
 521
 522 #ifdef CONFIG_HOTPLUG_CPU
 523 static int __cpuinit iucv_cpu_notify(struct notifier_block *self,
 524                                      unsigned long action, void *hcpu)
 525 {
 526         cpumask_t cpumask;
 527         long cpu = (long) hcpu;
 528
 529         switch (action) {
 530         case CPU_UP_PREPARE:
 531                 if (!percpu_populate(iucv_irq_data,
 532                                      sizeof(struct iucv_irq_data),
 533                                      GFP_KERNEL|GFP_DMA, cpu))
 534                         return NOTIFY_BAD;
 535                 if (!percpu_populate(iucv_param, sizeof(union iucv_param),
 536                                      GFP_KERNEL|GFP_DMA, cpu)) {
 537                         percpu_depopulate(iucv_irq_data, cpu);
 538                         return NOTIFY_BAD;
 539                 }
 540                 break;
 541         case CPU_UP_CANCELED:
 542         case CPU_DEAD:
 543                 percpu_depopulate(iucv_param, cpu);
 544                 percpu_depopulate(iucv_irq_data, cpu);
 545                 break;
 546         case CPU_ONLINE:
 547         case CPU_DOWN_FAILED:
 548                 smp_call_function_on(iucv_declare_cpu, NULL, 0, 1, cpu);
 549                 break;
 550         case CPU_DOWN_PREPARE:
 551                 cpumask = iucv_buffer_cpumask;
 552                 cpu_clear(cpu, cpumask);
 553                 if (cpus_empty(cpumask))
 554                         /* Can't offline last IUCV enabled cpu. */
 555                         return NOTIFY_BAD;
 556                 smp_call_function_on(iucv_retrieve_cpu, NULL, 0, 1, cpu);
 557                 if (cpus_empty(iucv_irq_cpumask))
 558                         smp_call_function_on(iucv_allow_cpu, NULL, 0, 1,
 559                                              first_cpu(iucv_buffer_cpumask));
 560                 break;
 561         }
 562         return NOTIFY_OK;
 563 }
 564
 565 static struct notifier_block iucv_cpu_notifier = {
 566         .notifier_call = iucv_cpu_notify,
 567 };
 568 #endif
 569
 570 /**
 571  * iucv_sever_pathid
 572  * @pathid: path identification number.
 573  * @userdata: 16-bytes of user data.
 574  *
 575  * Sever an iucv path to free up the pathid. Used internally.
 576  */
 577 static int iucv_sever_pathid(u16 pathid, u8 userdata[16])
 578 {
 579         union iucv_param *parm;
 580
 581         parm = percpu_ptr(iucv_param, smp_processor_id());
 582         memset(parm, 0, sizeof(union iucv_param));
 583         if (userdata)
 584                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 585         parm->ctrl.ippathid = pathid;
 586         return iucv_call_b2f0(IUCV_SEVER, parm);
 587 }
 588
 589 /**
 590  * __iucv_cleanup_pathid
 591  * @dummy: unused dummy argument
 592  *
 593  * Nop function called via smp_call_function to force work items from
 594  * pending external iucv interrupts to the work queue.
 595  */
 596 static void __iucv_cleanup_pathid(void *dummy)
 597 {
 598 }
 599
 600 /**
 601  * iucv_cleanup_pathid
 602  * @pathid: 16 bit pathid
 603  *
 604  * Function called after a path has been severed to find all remaining
 605  * work items for the now stale pathid. The caller needs to hold the
 606  * iucv_table_lock.
 607  */
 608 static void iucv_cleanup_pathid(u16 pathid)
 609 {
 610         struct iucv_work *p, *n;
 611
 612         /*
 613          * Path is severed, the pathid can be reused immediatly on
 614          * a iucv connect or a connection pending interrupt.
 615          * iucv_path_connect and connection pending interrupt will
 616          * wait until the iucv_table_lock is released before the
 617          * recycled pathid enters the system.
 618          * Force remaining interrupts to the work queue, then
 619          * scan the work queue for items of this path.
 620          */
 621         smp_call_function(__iucv_cleanup_pathid, NULL, 0, 1);
 622         spin_lock_irq(&iucv_work_lock);
 623         list_for_each_entry_safe(p, n, &iucv_work_queue, list) {
 624                 /* Remove work items for pathid except connection pending */
 625                 if (p->data.ippathid == pathid && p->data.iptype != 0x01) {
 626                         list_del(&p->list);
 627                         kfree(p);
 628                 }
 629         }
 630         spin_unlock_irq(&iucv_work_lock);
 631 }
 632
 633 /**
 634  * iucv_register:
 635  * @handler: address of iucv handler structure
 636  * @smp: != 0 indicates that the handler can deal with out of order messages
 637  *
 638  * Registers a driver with IUCV.
 639  *
 640  * Returns 0 on success, -ENOMEM if the memory allocation for the pathid
 641  * table failed, or -EIO if IUCV_DECLARE_BUFFER failed on all cpus.
 642  */
 643 int iucv_register(struct iucv_handler *handler, int smp)
 644 {
 645         int rc;
 646
 647         if (!iucv_available)
 648                 return -ENOSYS;
 649         mutex_lock(&iucv_register_mutex);
 650         if (!smp)
 651                 iucv_nonsmp_handler++;
 652         if (list_empty(&iucv_handler_list)) {
 653                 rc = iucv_enable();
 654                 if (rc)
 655                         goto out_mutex;
 656         } else if (!smp && iucv_nonsmp_handler == 1)
 657                 iucv_setmask_up();
 658         INIT_LIST_HEAD(&handler->paths);
 659
 660         spin_lock_irq(&iucv_table_lock);
 661         list_add_tail(&handler->list, &iucv_handler_list);
 662         spin_unlock_irq(&iucv_table_lock);
 663         rc = 0;
 664 out_mutex:
 665         mutex_unlock(&iucv_register_mutex);
 666         return rc;
 667 }
 668
 669 /**
 670  * iucv_unregister
 671  * @handler:  address of iucv handler structure
 672  * @smp: != 0 indicates that the handler can deal with out of order messages
 673  *
 674  * Unregister driver from IUCV.
 675  */
 676 void iucv_unregister(struct iucv_handler *handler, int smp)
 677 {
 678         struct iucv_path *p, *n;
 679
 680         mutex_lock(&iucv_register_mutex);
 681         spin_lock_bh(&iucv_table_lock);
 682         /* Remove handler from the iucv_handler_list. */
 683         list_del_init(&handler->list);
 684         /* Sever all pathids still refering to the handler. */
 685         list_for_each_entry_safe(p, n, &handler->paths, list) {
 686                 iucv_sever_pathid(p->pathid, NULL);
 687                 iucv_path_table[p->pathid] = NULL;
 688                 list_del(&p->list);
 689                 iucv_cleanup_pathid(p->pathid);
 690                 iucv_path_free(p);
 691         }
 692         spin_unlock_bh(&iucv_table_lock);
 693         if (!smp)
 694                 iucv_nonsmp_handler--;
 695         if (list_empty(&iucv_handler_list))
 696                 iucv_disable();
 697         else if (!smp && iucv_nonsmp_handler == 0)
 698                 iucv_setmask_mp();
 699         mutex_unlock(&iucv_register_mutex);
 700 }
 701
 702 /**
 703  * iucv_path_accept
 704  * @path: address of iucv path structure
 705  * @handler: address of iucv handler structure
 706  * @userdata: 16 bytes of data reflected to the communication partner
 707  * @private: private data passed to interrupt handlers for this path
 708  *
 709  * This function is issued after the user received a connection pending
 710  * external interrupt and now wishes to complete the IUCV communication path.
 711  *
 712  * Returns the result of the CP IUCV call.
 713  */
 714 int iucv_path_accept(struct iucv_path *path, struct iucv_handler *handler,
 715                      u8 userdata[16], void *private)
 716 {
 717         union iucv_param *parm;
 718         int rc;
 719
 720         local_bh_disable();
 721         /* Prepare parameter block. */
 722         parm = percpu_ptr(iucv_param, smp_processor_id());
 723         memset(parm, 0, sizeof(union iucv_param));
 724         parm->ctrl.ippathid = path->pathid;
 725         parm->ctrl.ipmsglim = path->msglim;
 726         if (userdata)
 727                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 728         parm->ctrl.ipflags1 = path->flags;
 729
 730         rc = iucv_call_b2f0(IUCV_ACCEPT, parm);
 731         if (!rc) {
 732                 path->private = private;
 733                 path->msglim = parm->ctrl.ipmsglim;
 734                 path->flags = parm->ctrl.ipflags1;
 735         }
 736         local_bh_enable();
 737         return rc;
 738 }
 739
 740 /**
 741  * iucv_path_connect
 742  * @path: address of iucv path structure
 743  * @handler: address of iucv handler structure
 744  * @userid: 8-byte user identification
 745  * @system: 8-byte target system identification
 746  * @userdata: 16 bytes of data reflected to the communication partner
 747  * @private: private data passed to interrupt handlers for this path
 748  *
 749  * This function establishes an IUCV path. Although the connect may complete
 750  * successfully, you are not able to use the path until you receive an IUCV
 751  * Connection Complete external interrupt.
 752  *
 753  * Returns the result of the CP IUCV call.
 754  */
 755 int iucv_path_connect(struct iucv_path *path, struct iucv_handler *handler,
 756                       u8 userid[8], u8 system[8], u8 userdata[16],
 757                       void *private)
 758 {
 759         union iucv_param *parm;
 760         int rc;
 761
 762         preempt_disable();
 763         if (iucv_tasklet_cpu != smp_processor_id())
 764                 spin_lock_bh(&iucv_table_lock);
 765         parm = percpu_ptr(iucv_param, smp_processor_id());
 766         memset(parm, 0, sizeof(union iucv_param));
 767         parm->ctrl.ipmsglim = path->msglim;
 768         parm->ctrl.ipflags1 = path->flags;
 769         if (userid) {
 770                 memcpy(parm->ctrl.ipvmid, userid, sizeof(parm->ctrl.ipvmid));
 771                 ASCEBC(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
 772                 EBC_TOUPPER(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
 773         }
 774         if (system) {
 775                 memcpy(parm->ctrl.iptarget, system,
 776                        sizeof(parm->ctrl.iptarget));
 777                 ASCEBC(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
 778                 EBC_TOUPPER(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
 779         }
 780         if (userdata)
 781                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 782
 783         rc = iucv_call_b2f0(IUCV_CONNECT, parm);
 784         if (!rc) {
 785                 if (parm->ctrl.ippathid < iucv_max_pathid) {
 786                         path->pathid = parm->ctrl.ippathid;
 787                         path->msglim = parm->ctrl.ipmsglim;
 788                         path->flags = parm->ctrl.ipflags1;
 789                         path->handler = handler;
 790                         path->private = private;
 791                         list_add_tail(&path->list, &handler->paths);
 792                         iucv_path_table[path->pathid] = path;
 793                 } else {
 794                         iucv_sever_pathid(parm->ctrl.ippathid,
 795                                           iucv_error_pathid);
 796                         rc = -EIO;
 797                 }
 798         }
 799         if (iucv_tasklet_cpu != smp_processor_id())
 800                 spin_unlock_bh(&iucv_table_lock);
 801         preempt_enable();
 802         return rc;
 803 }
 804
 805 /**
 806  * iucv_path_quiesce:
 807  * @path: address of iucv path structure
 808  * @userdata: 16 bytes of data reflected to the communication partner
 809  *
 810  * This function temporarily suspends incoming messages on an IUCV path.
 811  * You can later reactivate the path by invoking the iucv_resume function.
 812  *
 813  * Returns the result from the CP IUCV call.
 814  */
 815 int iucv_path_quiesce(struct iucv_path *path, u8 userdata[16])
 816 {
 817         union iucv_param *parm;
 818         int rc;
 819
 820         local_bh_disable();
 821         parm = percpu_ptr(iucv_param, smp_processor_id());
 822         memset(parm, 0, sizeof(union iucv_param));
 823         if (userdata)
 824                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 825         parm->ctrl.ippathid = path->pathid;
 826         rc = iucv_call_b2f0(IUCV_QUIESCE, parm);
 827         local_bh_enable();
 828         return rc;
 829 }
 830
 831 /**
 832  * iucv_path_resume:
 833  * @path: address of iucv path structure
 834  * @userdata: 16 bytes of data reflected to the communication partner
 835  *
 836  * This function resumes incoming messages on an IUCV path that has
 837  * been stopped with iucv_path_quiesce.
 838  *
 839  * Returns the result from the CP IUCV call.
 840  */
 841 int iucv_path_resume(struct iucv_path *path, u8 userdata[16])
 842 {
 843         union iucv_param *parm;
 844         int rc;
 845
 846         local_bh_disable();
 847         parm = percpu_ptr(iucv_param, smp_processor_id());
 848         memset(parm, 0, sizeof(union iucv_param));
 849         if (userdata)
 850                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 851         parm->ctrl.ippathid = path->pathid;
 852         rc = iucv_call_b2f0(IUCV_RESUME, parm);
 853         local_bh_enable();
 854         return rc;
 855 }
 856
 857 /**
 858  * iucv_path_sever
 859  * @path: address of iucv path structure
 860  * @userdata: 16 bytes of data reflected to the communication partner
 861  *
 862  * This function terminates an IUCV path.
 863  *
 864  * Returns the result from the CP IUCV call.
 865  */
 866 int iucv_path_sever(struct iucv_path *path, u8 userdata[16])
 867 {
 868         int rc;
 869
 870
 871         preempt_disable();
 872         if (iucv_tasklet_cpu != smp_processor_id())
 873                 spin_lock_bh(&iucv_table_lock);
 874         rc = iucv_sever_pathid(path->pathid, userdata);
 875         if (!rc) {
 876                 iucv_path_table[path->pathid] = NULL;
 877                 list_del_init(&path->list);
 878                 iucv_cleanup_pathid(path->pathid);
 879         }
 880         if (iucv_tasklet_cpu != smp_processor_id())
 881                 spin_unlock_bh(&iucv_table_lock);
 882         preempt_enable();
 883         return rc;
 884 }
 885
 886 /**
 887  * iucv_message_purge
 888  * @path: address of iucv path structure
 889  * @msg: address of iucv msg structure
 890  * @srccls: source class of message
 891  *
 892  * Cancels a message you have sent.
 893  *
 894  * Returns the result from the CP IUCV call.
 895  */
 896 int iucv_message_purge(struct iucv_path *path, struct iucv_message *msg,
 897                        u32 srccls)
 898 {
 899         union iucv_param *parm;
 900         int rc;
 901
 902         local_bh_disable();
 903         parm = percpu_ptr(iucv_param, smp_processor_id());
 904         memset(parm, 0, sizeof(union iucv_param));
 905         parm->purge.ippathid = path->pathid;
 906         parm->purge.ipmsgid = msg->id;
 907         parm->purge.ipsrccls = srccls;
 908         parm->purge.ipflags1 = IUCV_IPSRCCLS | IUCV_IPFGMID | IUCV_IPFGPID;
 909         rc = iucv_call_b2f0(IUCV_PURGE, parm);
 910         if (!rc) {
 911                 msg->audit = (*(u32 *) &parm->purge.ipaudit) >> 8;
 912                 msg->tag = parm->purge.ipmsgtag;
 913         }
 914         local_bh_enable();
 915         return rc;
 916 }
 917
 918 /**
 919  * iucv_message_receive
 920  * @path: address of iucv path structure
 921  * @msg: address of iucv msg structure
 922  * @flags: how the message is received (IUCV_IPBUFLST)
 923  * @buffer: address of data buffer or address of struct iucv_array
 924  * @size: length of data buffer
 925  * @residual:
 926  *
 927  * This function receives messages that are being sent to you over
 928  * established paths. This function will deal with RMDATA messages
 929  * embedded in struct iucv_message as well.
 930  *
 931  * Returns the result from the CP IUCV call.
 932  */
 933 int iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
 934                          u8 flags, void *buffer, size_t size, size_t *residual)
 935 {
 936         union iucv_param *parm;
 937         struct iucv_array *array;
 938         u8 *rmmsg;
 939         size_t copy;
 940         int rc;
 941
 942         if (msg->flags & IUCV_IPRMDATA) {
 943                 /*
 944                  * Message is 8 bytes long and has been stored to the
 945                  * message descriptor itself.
 946                  */
 947                 rc = (size < 8) ? 5 : 0;
 948                 if (residual)
 949                         *residual = abs(size - 8);
 950                 rmmsg = msg->rmmsg;
 951                 if (flags & IUCV_IPBUFLST) {
 952                         /* Copy to struct iucv_array. */
 953                         size = (size < 8) ? size : 8;
 954                         for (array = buffer; size > 0; array++) {
 955                                 copy = min_t(size_t, size, array->length);
 956                                 memcpy((u8 *)(addr_t) array->address,
 957                                        rmmsg, copy);
 958                                 rmmsg += copy;
 959                                 size -= copy;
 960                         }
 961                 } else {
 962                         /* Copy to direct buffer. */
 963                         memcpy(buffer, rmmsg, min_t(size_t, size, 8));
 964                 }
 965                 return 0;
 966         }
 967
 968         local_bh_disable();
 969         parm = percpu_ptr(iucv_param, smp_processor_id());
 970         memset(parm, 0, sizeof(union iucv_param));
 971         parm->db.ipbfadr1 = (u32)(addr_t) buffer;
 972         parm->db.ipbfln1f = (u32) size;
 973         parm->db.ipmsgid = msg->id;
 974         parm->db.ippathid = path->pathid;
 975         parm->db.iptrgcls = msg->class;
 976         parm->db.ipflags1 = (flags | IUCV_IPFGPID |
 977                              IUCV_IPFGMID | IUCV_IPTRGCLS);
 978         rc = iucv_call_b2f0(IUCV_RECEIVE, parm);
 979         if (!rc || rc == 5) {
 980                 msg->flags = parm->db.ipflags1;
 981                 if (residual)
 982                         *residual = parm->db.ipbfln1f;
 983         }
 984         local_bh_enable();
 985         return rc;
 986 }
 987
 988 /**
 989  * iucv_message_reject
 990  * @path: address of iucv path structure
 991  * @msg: address of iucv msg structure
 992  *
 993  * The reject function refuses a specified message. Between the time you
 994  * are notified of a message and the time that you complete the message,
 995  * the message may be rejected.
 996  *
 997  * Returns the result from the CP IUCV call.
 998  */
 999 int iucv_message_reject(struct iucv_path *path, struct iucv_message *msg)
1000 {
1001         union iucv_param *parm;
1002         int rc;
1003
1004         local_bh_disable();
1005         parm = percpu_ptr(iucv_param, smp_processor_id());
1006         memset(parm, 0, sizeof(union iucv_param));
1007         parm->db.ippathid = path->pathid;
1008         parm->db.ipmsgid = msg->id;
1009         parm->db.iptrgcls = msg->class;
1010         parm->db.ipflags1 = (IUCV_IPTRGCLS | IUCV_IPFGMID | IUCV_IPFGPID);
1011         rc = iucv_call_b2f0(IUCV_REJECT, parm);
1012         local_bh_enable();
1013         return rc;
1014 }
1015
1016 /**
1017  * iucv_message_reply
1018  * @path: address of iucv path structure
1019  * @msg: address of iucv msg structure
1020  * @flags: how the reply is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1021  * @reply: address of reply data buffer or address of struct iucv_array
1022  * @size: length of reply data buffer
1023  *
1024  * This function responds to the two-way messages that you receive. You
1025  * must identify completely the message to which you wish to reply. ie,
1026  * pathid, msgid, and trgcls. Prmmsg signifies the data is moved into
1027  * the parameter list.
1028  *
1029  * Returns the result from the CP IUCV call.
1030  */
1031 int iucv_message_reply(struct iucv_path *path, struct iucv_message *msg,
1032                        u8 flags, void *reply, size_t size)
1033 {
1034         union iucv_param *parm;
1035         int rc;
1036
1037         local_bh_disable();
1038         parm = percpu_ptr(iucv_param, smp_processor_id());
1039         memset(parm, 0, sizeof(union iucv_param));
1040         if (flags & IUCV_IPRMDATA) {
1041                 parm->dpl.ippathid = path->pathid;
1042                 parm->dpl.ipflags1 = flags;
1043                 parm->dpl.ipmsgid = msg->id;
1044                 parm->dpl.iptrgcls = msg->class;
1045                 memcpy(parm->dpl.iprmmsg, reply, min_t(size_t, size, 8));
1046         } else {
1047                 parm->db.ipbfadr1 = (u32)(addr_t) reply;
1048                 parm->db.ipbfln1f = (u32) size;
1049                 parm->db.ippathid = path->pathid;
1050                 parm->db.ipflags1 = flags;
1051                 parm->db.ipmsgid = msg->id;
1052                 parm->db.iptrgcls = msg->class;
1053         }
1054         rc = iucv_call_b2f0(IUCV_REPLY, parm);
1055         local_bh_enable();
1056         return rc;
1057 }
1058
1059 /**
1060  * iucv_message_send
1061  * @path: address of iucv path structure
1062  * @msg: address of iucv msg structure
1063  * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1064  * @srccls: source class of message
1065  * @buffer: address of send buffer or address of struct iucv_array
1066  * @size: length of send buffer
1067  *
1068  * This function transmits data to another application. Data to be
1069  * transmitted is in a buffer and this is a one-way message and the
1070  * receiver will not reply to the message.
1071  *
1072  * Returns the result from the CP IUCV call.
1073  */
1074 int iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
1075                       u8 flags, u32 srccls, void *buffer, size_t size)
1076 {
1077         union iucv_param *parm;
1078         int rc;
1079
1080         local_bh_disable();
1081         parm = percpu_ptr(iucv_param, smp_processor_id());
1082         memset(parm, 0, sizeof(union iucv_param));
1083         if (flags & IUCV_IPRMDATA) {
1084                 /* Message of 8 bytes can be placed into the parameter list. */
1085                 parm->dpl.ippathid = path->pathid;
1086                 parm->dpl.ipflags1 = flags | IUCV_IPNORPY;
1087                 parm->dpl.iptrgcls = msg->class;
1088                 parm->dpl.ipsrccls = srccls;
1089                 parm->dpl.ipmsgtag = msg->tag;
1090                 memcpy(parm->dpl.iprmmsg, buffer, 8);
1091         } else {
1092                 parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1093                 parm->db.ipbfln1f = (u32) size;
1094                 parm->db.ippathid = path->pathid;
1095                 parm->db.ipflags1 = flags | IUCV_IPNORPY;
1096                 parm->db.iptrgcls = msg->class;
1097                 parm->db.ipsrccls = srccls;
1098                 parm->db.ipmsgtag = msg->tag;
1099         }
1100         rc = iucv_call_b2f0(IUCV_SEND, parm);
1101         if (!rc)
1102                 msg->id = parm->db.ipmsgid;
1103         local_bh_enable();
1104         return rc;
1105 }
1106
1107 /**
1108  * iucv_message_send2way
1109  * @path: address of iucv path structure
1110  * @msg: address of iucv msg structure
1111  * @flags: how the message is sent and the reply is received
1112  *         (IUCV_IPRMDATA, IUCV_IPBUFLST, IUCV_IPPRTY, IUCV_ANSLST)
1113  * @srccls: source class of message
1114  * @buffer: address of send buffer or address of struct iucv_array
1115  * @size: length of send buffer
1116  * @ansbuf: address of answer buffer or address of struct iucv_array
1117  * @asize: size of reply buffer
1118  *
1119  * This function transmits data to another application. Data to be
1120  * transmitted is in a buffer. The receiver of the send is expected to
1121  * reply to the message and a buffer is provided into which IUCV moves
1122  * the reply to this message.
1123  *
1124  * Returns the result from the CP IUCV call.
1125  */
1126 int iucv_message_send2way(struct iucv_path *path, struct iucv_message *msg,
1127                           u8 flags, u32 srccls, void *buffer, size_t size,
1128                           void *answer, size_t asize, size_t *residual)
1129 {
1130         union iucv_param *parm;
1131         int rc;
1132
1133         local_bh_disable();
1134         parm = percpu_ptr(iucv_param, smp_processor_id());
1135         memset(parm, 0, sizeof(union iucv_param));
1136         if (flags & IUCV_IPRMDATA) {
1137                 parm->dpl.ippathid = path->pathid;
1138                 parm->dpl.ipflags1 = path->flags;       /* priority message */
1139                 parm->dpl.iptrgcls = msg->class;
1140                 parm->dpl.ipsrccls = srccls;
1141                 parm->dpl.ipmsgtag = msg->tag;
1142                 parm->dpl.ipbfadr2 = (u32)(addr_t) answer;
1143                 parm->dpl.ipbfln2f = (u32) asize;
1144                 memcpy(parm->dpl.iprmmsg, buffer, 8);
1145         } else {
1146                 parm->db.ippathid = path->pathid;
1147                 parm->db.ipflags1 = path->flags;        /* priority message */
1148                 parm->db.iptrgcls = msg->class;
1149                 parm->db.ipsrccls = srccls;
1150                 parm->db.ipmsgtag = msg->tag;
1151                 parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1152                 parm->db.ipbfln1f = (u32) size;
1153                 parm->db.ipbfadr2 = (u32)(addr_t) answer;
1154                 parm->db.ipbfln2f = (u32) asize;
1155         }
1156         rc = iucv_call_b2f0(IUCV_SEND, parm);
1157         if (!rc)
1158                 msg->id = parm->db.ipmsgid;
1159         local_bh_enable();
1160         return rc;
1161 }
1162
1163 /**
1164  * iucv_path_pending
1165  * @data: Pointer to external interrupt buffer
1166  *
1167  * Process connection pending work item. Called from tasklet while holding
1168  * iucv_table_lock.
1169  */
1170 struct iucv_path_pending {
1171         u16 ippathid;
1172         u8  ipflags1;
1173         u8  iptype;
1174         u16 ipmsglim;
1175         u16 res1;
1176         u8  ipvmid[8];
1177         u8  ipuser[16];
1178         u32 res3;
1179         u8  ippollfg;
1180         u8  res4[3];
1181 } __attribute__ ((packed));
1182
1183 static void iucv_path_pending(struct iucv_irq_data *data)
1184 {
1185         struct iucv_path_pending *ipp = (void *) data;
1186         struct iucv_handler *handler;
1187         struct iucv_path *path;
1188         char *error;
1189
1190         BUG_ON(iucv_path_table[ipp->ippathid]);
1191         /* New pathid, handler found. Create a new path struct. */
1192         error = iucv_error_no_memory;
1193         path = iucv_path_alloc(ipp->ipmsglim, ipp->ipflags1, GFP_ATOMIC);
1194         if (!path)
1195                 goto out_sever;
1196         path->pathid = ipp->ippathid;
1197         iucv_path_table[path->pathid] = path;
1198         EBCASC(ipp->ipvmid, 8);
1199
1200         /* Call registered handler until one is found that wants the path. */
1201         list_for_each_entry(handler, &iucv_handler_list, list) {
1202                 if (!handler->path_pending)
1203                         continue;
1204                 /*
1205                  * Add path to handler to allow a call to iucv_path_sever
1206                  * inside the path_pending function. If the handler returns
1207                  * an error remove the path from the handler again.
1208                  */
1209                 list_add(&path->list, &handler->paths);
1210                 path->handler = handler;
1211                 if (!handler->path_pending(path, ipp->ipvmid, ipp->ipuser))
1212                         return;
1213                 list_del(&path->list);
1214                 path->handler = NULL;
1215         }
1216         /* No handler wanted the path. */
1217         iucv_path_table[path->pathid] = NULL;
1218         iucv_path_free(path);
1219         error = iucv_error_no_listener;
1220 out_sever:
1221         iucv_sever_pathid(ipp->ippathid, error);
1222 }
1223
1224 /**
1225  * iucv_path_complete
1226  * @data: Pointer to external interrupt buffer
1227  *
1228  * Process connection complete work item. Called from tasklet while holding
1229  * iucv_table_lock.
1230  */
1231 struct iucv_path_complete {
1232         u16 ippathid;
1233         u8  ipflags1;
1234         u8  iptype;
1235         u16 ipmsglim;
1236         u16 res1;
1237         u8  res2[8];
1238         u8  ipuser[16];
1239         u32 res3;
1240         u8  ippollfg;
1241         u8  res4[3];
1242 } __attribute__ ((packed));
1243
1244 static void iucv_path_complete(struct iucv_irq_data *data)
1245 {
1246         struct iucv_path_complete *ipc = (void *) data;
1247         struct iucv_path *path = iucv_path_table[ipc->ippathid];
1248
1249         BUG_ON(!path || !path->handler);
1250         if (path->handler->path_complete)
1251                 path->handler->path_complete(path, ipc->ipuser);
1252 }
1253
1254 /**
1255  * iucv_path_severed
1256  * @data: Pointer to external interrupt buffer
1257  *
1258  * Process connection severed work item. Called from tasklet while holding
1259  * iucv_table_lock.
1260  */
1261 struct iucv_path_severed {
1262         u16 ippathid;
1263         u8  res1;
1264         u8  iptype;
1265         u32 res2;
1266         u8  res3[8];
1267         u8  ipuser[16];
1268         u32 res4;
1269         u8  ippollfg;
1270         u8  res5[3];
1271 } __attribute__ ((packed));
1272
1273 static void iucv_path_severed(struct iucv_irq_data *data)
1274 {
1275         struct iucv_path_severed *ips = (void *) data;
1276         struct iucv_path *path = iucv_path_table[ips->ippathid];
1277
1278         BUG_ON(!path || !path->handler);
1279         if (path->handler->path_severed)
1280                 path->handler->path_severed(path, ips->ipuser);
1281         else {
1282                 iucv_sever_pathid(path->pathid, NULL);
1283                 iucv_path_table[path->pathid] = NULL;
1284                 list_del_init(&path->list);
1285                 iucv_cleanup_pathid(path->pathid);
1286                 iucv_path_free(path);
1287         }
1288 }
1289
1290 /**
1291  * iucv_path_quiesced
1292  * @data: Pointer to external interrupt buffer
1293  *
1294  * Process connection quiesced work item. Called from tasklet while holding
1295  * iucv_table_lock.
1296  */
1297 struct iucv_path_quiesced {
1298         u16 ippathid;
1299         u8  res1;
1300         u8  iptype;
1301         u32 res2;
1302         u8  res3[8];
1303         u8  ipuser[16];
1304         u32 res4;
1305         u8  ippollfg;
1306         u8  res5[3];
1307 } __attribute__ ((packed));
1308
1309 static void iucv_path_quiesced(struct iucv_irq_data *data)
1310 {
1311         struct iucv_path_quiesced *ipq = (void *) data;
1312         struct iucv_path *path = iucv_path_table[ipq->ippathid];
1313
1314         BUG_ON(!path || !path->handler);
1315         if (path->handler->path_quiesced)
1316                 path->handler->path_quiesced(path, ipq->ipuser);
1317 }
1318
1319 /**
1320  * iucv_path_resumed
1321  * @data: Pointer to external interrupt buffer
1322  *
1323  * Process connection resumed work item. Called from tasklet while holding
1324  * iucv_table_lock.
1325  */
1326 struct iucv_path_resumed {
1327         u16 ippathid;
1328         u8  res1;
1329         u8  iptype;
1330         u32 res2;
1331         u8  res3[8];
1332         u8  ipuser[16];
1333         u32 res4;
1334         u8  ippollfg;
1335         u8  res5[3];
1336 } __attribute__ ((packed));
1337
1338 static void iucv_path_resumed(struct iucv_irq_data *data)
1339 {
1340         struct iucv_path_resumed *ipr = (void *) data;
1341         struct iucv_path *path = iucv_path_table[ipr->ippathid];
1342
1343         BUG_ON(!path || !path->handler);
1344         if (path->handler->path_resumed)
1345                 path->handler->path_resumed(path, ipr->ipuser);
1346 }
1347
1348 /**
1349  * iucv_message_complete
1350  * @data: Pointer to external interrupt buffer
1351  *
1352  * Process message complete work item. Called from tasklet while holding
1353  * iucv_table_lock.
1354  */
1355 struct iucv_message_complete {
1356         u16 ippathid;
1357         u8  ipflags1;
1358         u8  iptype;
1359         u32 ipmsgid;
1360         u32 ipaudit;
1361         u8  iprmmsg[8];
1362         u32 ipsrccls;
1363         u32 ipmsgtag;
1364         u32 res;
1365         u32 ipbfln2f;
1366         u8  ippollfg;
1367         u8  res2[3];
1368 } __attribute__ ((packed));
1369
1370 static void iucv_message_complete(struct iucv_irq_data *data)
1371 {
1372         struct iucv_message_complete *imc = (void *) data;
1373         struct iucv_path *path = iucv_path_table[imc->ippathid];
1374         struct iucv_message msg;
1375
1376         BUG_ON(!path || !path->handler);
1377         if (path->handler->message_complete) {
1378                 msg.flags = imc->ipflags1;
1379                 msg.id = imc->ipmsgid;
1380                 msg.audit = imc->ipaudit;
1381                 memcpy(msg.rmmsg, imc->iprmmsg, 8);
1382                 msg.class = imc->ipsrccls;
1383                 msg.tag = imc->ipmsgtag;
1384                 msg.length = imc->ipbfln2f;
1385                 path->handler->message_complete(path, &msg);
1386         }
1387 }
1388
1389 /**
1390  * iucv_message_pending
1391  * @data: Pointer to external interrupt buffer
1392  *
1393  * Process message pending work item. Called from tasklet while holding
1394  * iucv_table_lock.
1395  */
1396 struct iucv_message_pending {
1397         u16 ippathid;
1398         u8  ipflags1;
1399         u8  iptype;
1400         u32 ipmsgid;
1401         u32 iptrgcls;
1402         union {
1403                 u32 iprmmsg1_u32;
1404                 u8  iprmmsg1[4];
1405         } ln1msg1;
1406         union {
1407                 u32 ipbfln1f;
1408                 u8  iprmmsg2[4];
1409         } ln1msg2;
1410         u32 res1[3];
1411         u32 ipbfln2f;
1412         u8  ippollfg;
1413         u8  res2[3];
1414 } __attribute__ ((packed));
1415
1416 static void iucv_message_pending(struct iucv_irq_data *data)
1417 {
1418         struct iucv_message_pending *imp = (void *) data;
1419         struct iucv_path *path = iucv_path_table[imp->ippathid];
1420         struct iucv_message msg;
1421
1422         BUG_ON(!path || !path->handler);
1423         if (path->handler->message_pending) {
1424                 msg.flags = imp->ipflags1;
1425                 msg.id = imp->ipmsgid;
1426                 msg.class = imp->iptrgcls;
1427                 if (imp->ipflags1 & IUCV_IPRMDATA) {
1428                         memcpy(msg.rmmsg, imp->ln1msg1.iprmmsg1, 8);
1429                         msg.length = 8;
1430                 } else
1431                         msg.length = imp->ln1msg2.ipbfln1f;
1432                 msg.reply_size = imp->ipbfln2f;
1433                 path->handler->message_pending(path, &msg);
1434         }
1435 }
1436
1437 /**
1438  * iucv_tasklet_handler:
1439  *
1440  * This tasklet loops over the queue of irq buffers created by
1441  * iucv_external_interrupt, calls the appropriate action handler
1442  * and then frees the buffer.
1443  */
1444 static void iucv_tasklet_handler(unsigned long ignored)
1445 {
1446         typedef void iucv_irq_fn(struct iucv_irq_data *);
1447         static iucv_irq_fn *irq_fn[] = {
1448                 [0x01] = iucv_path_pending,
1449                 [0x02] = iucv_path_complete,
1450                 [0x03] = iucv_path_severed,
1451                 [0x04] = iucv_path_quiesced,
1452                 [0x05] = iucv_path_resumed,
1453                 [0x06] = iucv_message_complete,
1454                 [0x07] = iucv_message_complete,
1455                 [0x08] = iucv_message_pending,
1456                 [0x09] = iucv_message_pending,
1457         };
1458         struct iucv_work *p;
1459
1460         /* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1461         spin_lock(&iucv_table_lock);
1462         iucv_tasklet_cpu = smp_processor_id();
1463
1464         spin_lock_irq(&iucv_work_lock);
1465         while (!list_empty(&iucv_work_queue)) {
1466                 p = list_entry(iucv_work_queue.next, struct iucv_work, list);
1467                 list_del_init(&p->list);
1468                 spin_unlock_irq(&iucv_work_lock);
1469                 irq_fn[p->data.iptype](&p->data);
1470                 kfree(p);
1471                 spin_lock_irq(&iucv_work_lock);
1472         }
1473         spin_unlock_irq(&iucv_work_lock);
1474
1475         iucv_tasklet_cpu = -1;
1476         spin_unlock(&iucv_table_lock);
1477 }
1478
1479 /**
1480  * iucv_external_interrupt
1481  * @code: irq code
1482  *
1483  * Handles external interrupts coming in from CP.
1484  * Places the interrupt buffer on a queue and schedules iucv_tasklet_handler().
1485  */
1486 static void iucv_external_interrupt(u16 code)
1487 {
1488         struct iucv_irq_data *p;
1489         struct iucv_work *work;
1490
1491         p = percpu_ptr(iucv_irq_data, smp_processor_id());
1492         if (p->ippathid >= iucv_max_pathid) {
1493                 printk(KERN_WARNING "iucv_do_int: Got interrupt with "
1494                        "pathid %d > max_connections (%ld)\n",
1495                        p->ippathid, iucv_max_pathid - 1);
1496                 iucv_sever_pathid(p->ippathid, iucv_error_no_listener);
1497                 return;
1498         }
1499         if (p->iptype  < 0x01 || p->iptype > 0x09) {
1500                 printk(KERN_ERR "iucv_do_int: unknown iucv interrupt\n");
1501                 return;
1502         }
1503         work = kmalloc(sizeof(struct iucv_work), GFP_ATOMIC);
1504         if (!work) {
1505                 printk(KERN_WARNING "iucv_external_interrupt: out of memory\n");
1506                 return;
1507         }
1508         memcpy(&work->data, p, sizeof(work->data));
1509         spin_lock(&iucv_work_lock);
1510         list_add_tail(&work->list, &iucv_work_queue);
1511         spin_unlock(&iucv_work_lock);
1512         tasklet_schedule(&iucv_tasklet);
1513 }
1514
1515 /**
1516  * iucv_init
1517  *
1518  * Allocates and initializes various data structures.
1519  */
1520 static int iucv_init(void)
1521 {
1522         int rc;
1523
1524         if (!MACHINE_IS_VM) {
1525                 rc = -EPROTONOSUPPORT;
1526                 goto out;
1527         }
1528         rc = iucv_query_maxconn();
1529         if (rc)
1530                 goto out;
1531         rc = register_external_interrupt (0x4000, iucv_external_interrupt);
1532         if (rc)
1533                 goto out;
1534         rc = bus_register(&iucv_bus);
1535         if (rc)
1536                 goto out_int;
1537         iucv_root = s390_root_dev_register("iucv");
1538         if (IS_ERR(iucv_root)) {
1539                 rc = PTR_ERR(iucv_root);
1540                 goto out_bus;
1541         }
1542         /* Note: GFP_DMA used used to get memory below 2G */
1543         iucv_irq_data = percpu_alloc(sizeof(struct iucv_irq_data),
1544                                      GFP_KERNEL|GFP_DMA);
1545         if (!iucv_irq_data) {
1546                 rc = -ENOMEM;
1547                 goto out_root;
1548         }
1549         /* Allocate parameter blocks. */
1550         iucv_param = percpu_alloc(sizeof(union iucv_param),
1551                                   GFP_KERNEL|GFP_DMA);
1552         if (!iucv_param) {
1553                 rc = -ENOMEM;
1554                 goto out_extint;
1555         }
1556         register_hotcpu_notifier(&iucv_cpu_notifier);
1557         ASCEBC(iucv_error_no_listener, 16);
1558         ASCEBC(iucv_error_no_memory, 16);
1559         ASCEBC(iucv_error_pathid, 16);
1560         iucv_available = 1;
1561         return 0;
1562
1563 out_extint:
1564         percpu_free(iucv_irq_data);
1565 out_root:
1566         s390_root_dev_unregister(iucv_root);
1567 out_bus:
1568         bus_unregister(&iucv_bus);
1569 out_int:
1570         unregister_external_interrupt(0x4000, iucv_external_interrupt);
1571 out:
1572         return rc;
1573 }
1574
1575 /**
1576  * iucv_exit
1577  *
1578  * Frees everything allocated from iucv_init.
1579  */
1580 static void iucv_exit(void)
1581 {
1582         struct iucv_work *p, *n;
1583
1584         spin_lock_irq(&iucv_work_lock);
1585         list_for_each_entry_safe(p, n, &iucv_work_queue, list)
1586                 kfree(p);
1587         spin_unlock_irq(&iucv_work_lock);
1588         unregister_hotcpu_notifier(&iucv_cpu_notifier);
1589         percpu_free(iucv_param);
1590         percpu_free(iucv_irq_data);
1591         s390_root_dev_unregister(iucv_root);
1592         bus_unregister(&iucv_bus);
1593         unregister_external_interrupt(0x4000, iucv_external_interrupt);
1594 }
1595
1596 subsys_initcall(iucv_init);
1597 module_exit(iucv_exit);
1598
1599 /**
1600  * Export all public stuff
1601  */
1602 EXPORT_SYMBOL (iucv_bus);
1603 EXPORT_SYMBOL (iucv_root);
1604 EXPORT_SYMBOL (iucv_register);
1605 EXPORT_SYMBOL (iucv_unregister);
1606 EXPORT_SYMBOL (iucv_path_accept);
1607 EXPORT_SYMBOL (iucv_path_connect);
1608 EXPORT_SYMBOL (iucv_path_quiesce);
1609 EXPORT_SYMBOL (iucv_path_sever);
1610 EXPORT_SYMBOL (iucv_message_purge);
1611 EXPORT_SYMBOL (iucv_message_receive);
1612 EXPORT_SYMBOL (iucv_message_reject);
1613 EXPORT_SYMBOL (iucv_message_reply);
1614 EXPORT_SYMBOL (iucv_message_send);
1615 EXPORT_SYMBOL (iucv_message_send2way);
1616
1617 MODULE_AUTHOR("(C) 2001 IBM Corp. by Fritz Elfert (felfert@millenux.com)");
1618 MODULE_DESCRIPTION("Linux for S/390 IUCV lowlevel driver");
1619 MODULE_LICENSE("GPL");