git.oblomov.eu Git - linux-2.6/blob - 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 static int __cpuinit iucv_cpu_notify(struct notifier_block *self,
 523                                      unsigned long action, void *hcpu)
 524 {
 525         cpumask_t cpumask;
 526         long cpu = (long) hcpu;
 527
 528         switch (action) {
 529         case CPU_UP_PREPARE:
 530                 if (!percpu_populate(iucv_irq_data,
 531                                      sizeof(struct iucv_irq_data),
 532                                      GFP_KERNEL|GFP_DMA, cpu))
 533                         return NOTIFY_BAD;
 534                 if (!percpu_populate(iucv_param, sizeof(union iucv_param),
 535                                      GFP_KERNEL|GFP_DMA, cpu)) {
 536                         percpu_depopulate(iucv_irq_data, cpu);
 537                         return NOTIFY_BAD;
 538                 }
 539                 break;
 540         case CPU_UP_CANCELED:
 541         case CPU_DEAD:
 542                 percpu_depopulate(iucv_param, cpu);
 543                 percpu_depopulate(iucv_irq_data, cpu);
 544                 break;
 545         case CPU_ONLINE:
 546         case CPU_DOWN_FAILED:
 547                 smp_call_function_on(iucv_declare_cpu, NULL, 0, 1, cpu);
 548                 break;
 549         case CPU_DOWN_PREPARE:
 550                 cpumask = iucv_buffer_cpumask;
 551                 cpu_clear(cpu, cpumask);
 552                 if (cpus_empty(cpumask))
 553                         /* Can't offline last IUCV enabled cpu. */
 554                         return NOTIFY_BAD;
 555                 smp_call_function_on(iucv_retrieve_cpu, NULL, 0, 1, cpu);
 556                 if (cpus_empty(iucv_irq_cpumask))
 557                         smp_call_function_on(iucv_allow_cpu, NULL, 0, 1,
 558                                              first_cpu(iucv_buffer_cpumask));
 559                 break;
 560         }
 561         return NOTIFY_OK;
 562 }
 563
 564 static struct notifier_block iucv_cpu_notifier = {
 565         .notifier_call = iucv_cpu_notify,
 566 };
 567
 568 /**
 569  * iucv_sever_pathid
 570  * @pathid: path identification number.
 571  * @userdata: 16-bytes of user data.
 572  *
 573  * Sever an iucv path to free up the pathid. Used internally.
 574  */
 575 static int iucv_sever_pathid(u16 pathid, u8 userdata[16])
 576 {
 577         union iucv_param *parm;
 578
 579         parm = percpu_ptr(iucv_param, smp_processor_id());
 580         memset(parm, 0, sizeof(union iucv_param));
 581         if (userdata)
 582                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 583         parm->ctrl.ippathid = pathid;
 584         return iucv_call_b2f0(IUCV_SEVER, parm);
 585 }
 586
 587 /**
 588  * __iucv_cleanup_pathid
 589  * @dummy: unused dummy argument
 590  *
 591  * Nop function called via smp_call_function to force work items from
 592  * pending external iucv interrupts to the work queue.
 593  */
 594 static void __iucv_cleanup_pathid(void *dummy)
 595 {
 596 }
 597
 598 /**
 599  * iucv_cleanup_pathid
 600  * @pathid: 16 bit pathid
 601  *
 602  * Function called after a path has been severed to find all remaining
 603  * work items for the now stale pathid. The caller needs to hold the
 604  * iucv_table_lock.
 605  */
 606 static void iucv_cleanup_pathid(u16 pathid)
 607 {
 608         struct iucv_work *p, *n;
 609
 610         /*
 611          * Path is severed, the pathid can be reused immediatly on
 612          * a iucv connect or a connection pending interrupt.
 613          * iucv_path_connect and connection pending interrupt will
 614          * wait until the iucv_table_lock is released before the
 615          * recycled pathid enters the system.
 616          * Force remaining interrupts to the work queue, then
 617          * scan the work queue for items of this path.
 618          */
 619         smp_call_function(__iucv_cleanup_pathid, NULL, 0, 1);
 620         spin_lock_irq(&iucv_work_lock);
 621         list_for_each_entry_safe(p, n, &iucv_work_queue, list) {
 622                 /* Remove work items for pathid except connection pending */
 623                 if (p->data.ippathid == pathid && p->data.iptype != 0x01) {
 624                         list_del(&p->list);
 625                         kfree(p);
 626                 }
 627         }
 628         spin_unlock_irq(&iucv_work_lock);
 629 }
 630
 631 /**
 632  * iucv_register:
 633  * @handler: address of iucv handler structure
 634  * @smp: != 0 indicates that the handler can deal with out of order messages
 635  *
 636  * Registers a driver with IUCV.
 637  *
 638  * Returns 0 on success, -ENOMEM if the memory allocation for the pathid
 639  * table failed, or -EIO if IUCV_DECLARE_BUFFER failed on all cpus.
 640  */
 641 int iucv_register(struct iucv_handler *handler, int smp)
 642 {
 643         int rc;
 644
 645         if (!iucv_available)
 646                 return -ENOSYS;
 647         mutex_lock(&iucv_register_mutex);
 648         if (!smp)
 649                 iucv_nonsmp_handler++;
 650         if (list_empty(&iucv_handler_list)) {
 651                 rc = iucv_enable();
 652                 if (rc)
 653                         goto out_mutex;
 654         } else if (!smp && iucv_nonsmp_handler == 1)
 655                 iucv_setmask_up();
 656         INIT_LIST_HEAD(&handler->paths);
 657
 658         spin_lock_irq(&iucv_table_lock);
 659         list_add_tail(&handler->list, &iucv_handler_list);
 660         spin_unlock_irq(&iucv_table_lock);
 661         rc = 0;
 662 out_mutex:
 663         mutex_unlock(&iucv_register_mutex);
 664         return rc;
 665 }
 666
 667 /**
 668  * iucv_unregister
 669  * @handler:  address of iucv handler structure
 670  * @smp: != 0 indicates that the handler can deal with out of order messages
 671  *
 672  * Unregister driver from IUCV.
 673  */
 674 void iucv_unregister(struct iucv_handler *handler, int smp)
 675 {
 676         struct iucv_path *p, *n;
 677
 678         mutex_lock(&iucv_register_mutex);
 679         spin_lock_bh(&iucv_table_lock);
 680         /* Remove handler from the iucv_handler_list. */
 681         list_del_init(&handler->list);
 682         /* Sever all pathids still refering to the handler. */
 683         list_for_each_entry_safe(p, n, &handler->paths, list) {
 684                 iucv_sever_pathid(p->pathid, NULL);
 685                 iucv_path_table[p->pathid] = NULL;
 686                 list_del(&p->list);
 687                 iucv_cleanup_pathid(p->pathid);
 688                 iucv_path_free(p);
 689         }
 690         spin_unlock_bh(&iucv_table_lock);
 691         if (!smp)
 692                 iucv_nonsmp_handler--;
 693         if (list_empty(&iucv_handler_list))
 694                 iucv_disable();
 695         else if (!smp && iucv_nonsmp_handler == 0)
 696                 iucv_setmask_mp();
 697         mutex_unlock(&iucv_register_mutex);
 698 }
 699
 700 /**
 701  * iucv_path_accept
 702  * @path: address of iucv path structure
 703  * @handler: address of iucv handler structure
 704  * @userdata: 16 bytes of data reflected to the communication partner
 705  * @private: private data passed to interrupt handlers for this path
 706  *
 707  * This function is issued after the user received a connection pending
 708  * external interrupt and now wishes to complete the IUCV communication path.
 709  *
 710  * Returns the result of the CP IUCV call.
 711  */
 712 int iucv_path_accept(struct iucv_path *path, struct iucv_handler *handler,
 713                      u8 userdata[16], void *private)
 714 {
 715         union iucv_param *parm;
 716         int rc;
 717
 718         local_bh_disable();
 719         /* Prepare parameter block. */
 720         parm = percpu_ptr(iucv_param, smp_processor_id());
 721         memset(parm, 0, sizeof(union iucv_param));
 722         parm->ctrl.ippathid = path->pathid;
 723         parm->ctrl.ipmsglim = path->msglim;
 724         if (userdata)
 725                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 726         parm->ctrl.ipflags1 = path->flags;
 727
 728         rc = iucv_call_b2f0(IUCV_ACCEPT, parm);
 729         if (!rc) {
 730                 path->private = private;
 731                 path->msglim = parm->ctrl.ipmsglim;
 732                 path->flags = parm->ctrl.ipflags1;
 733         }
 734         local_bh_enable();
 735         return rc;
 736 }
 737
 738 /**
 739  * iucv_path_connect
 740  * @path: address of iucv path structure
 741  * @handler: address of iucv handler structure
 742  * @userid: 8-byte user identification
 743  * @system: 8-byte target system identification
 744  * @userdata: 16 bytes of data reflected to the communication partner
 745  * @private: private data passed to interrupt handlers for this path
 746  *
 747  * This function establishes an IUCV path. Although the connect may complete
 748  * successfully, you are not able to use the path until you receive an IUCV
 749  * Connection Complete external interrupt.
 750  *
 751  * Returns the result of the CP IUCV call.
 752  */
 753 int iucv_path_connect(struct iucv_path *path, struct iucv_handler *handler,
 754                       u8 userid[8], u8 system[8], u8 userdata[16],
 755                       void *private)
 756 {
 757         union iucv_param *parm;
 758         int rc;
 759
 760         preempt_disable();
 761         if (iucv_tasklet_cpu != smp_processor_id())
 762                 spin_lock_bh(&iucv_table_lock);
 763         parm = percpu_ptr(iucv_param, smp_processor_id());
 764         memset(parm, 0, sizeof(union iucv_param));
 765         parm->ctrl.ipmsglim = path->msglim;
 766         parm->ctrl.ipflags1 = path->flags;
 767         if (userid) {
 768                 memcpy(parm->ctrl.ipvmid, userid, sizeof(parm->ctrl.ipvmid));
 769                 ASCEBC(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
 770                 EBC_TOUPPER(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
 771         }
 772         if (system) {
 773                 memcpy(parm->ctrl.iptarget, system,
 774                        sizeof(parm->ctrl.iptarget));
 775                 ASCEBC(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
 776                 EBC_TOUPPER(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
 777         }
 778         if (userdata)
 779                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 780
 781         rc = iucv_call_b2f0(IUCV_CONNECT, parm);
 782         if (!rc) {
 783                 if (parm->ctrl.ippathid < iucv_max_pathid) {
 784                         path->pathid = parm->ctrl.ippathid;
 785                         path->msglim = parm->ctrl.ipmsglim;
 786                         path->flags = parm->ctrl.ipflags1;
 787                         path->handler = handler;
 788                         path->private = private;
 789                         list_add_tail(&path->list, &handler->paths);
 790                         iucv_path_table[path->pathid] = path;
 791                 } else {
 792                         iucv_sever_pathid(parm->ctrl.ippathid,
 793                                           iucv_error_pathid);
 794                         rc = -EIO;
 795                 }
 796         }
 797         if (iucv_tasklet_cpu != smp_processor_id())
 798                 spin_unlock_bh(&iucv_table_lock);
 799         preempt_enable();
 800         return rc;
 801 }
 802
 803 /**
 804  * iucv_path_quiesce:
 805  * @path: address of iucv path structure
 806  * @userdata: 16 bytes of data reflected to the communication partner
 807  *
 808  * This function temporarily suspends incoming messages on an IUCV path.
 809  * You can later reactivate the path by invoking the iucv_resume function.
 810  *
 811  * Returns the result from the CP IUCV call.
 812  */
 813 int iucv_path_quiesce(struct iucv_path *path, u8 userdata[16])
 814 {
 815         union iucv_param *parm;
 816         int rc;
 817
 818         local_bh_disable();
 819         parm = percpu_ptr(iucv_param, smp_processor_id());
 820         memset(parm, 0, sizeof(union iucv_param));
 821         if (userdata)
 822                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 823         parm->ctrl.ippathid = path->pathid;
 824         rc = iucv_call_b2f0(IUCV_QUIESCE, parm);
 825         local_bh_enable();
 826         return rc;
 827 }
 828
 829 /**
 830  * iucv_path_resume:
 831  * @path: address of iucv path structure
 832  * @userdata: 16 bytes of data reflected to the communication partner
 833  *
 834  * This function resumes incoming messages on an IUCV path that has
 835  * been stopped with iucv_path_quiesce.
 836  *
 837  * Returns the result from the CP IUCV call.
 838  */
 839 int iucv_path_resume(struct iucv_path *path, u8 userdata[16])
 840 {
 841         union iucv_param *parm;
 842         int rc;
 843
 844         local_bh_disable();
 845         parm = percpu_ptr(iucv_param, smp_processor_id());
 846         memset(parm, 0, sizeof(union iucv_param));
 847         if (userdata)
 848                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 849         parm->ctrl.ippathid = path->pathid;
 850         rc = iucv_call_b2f0(IUCV_RESUME, parm);
 851         local_bh_enable();
 852         return rc;
 853 }
 854
 855 /**
 856  * iucv_path_sever
 857  * @path: address of iucv path structure
 858  * @userdata: 16 bytes of data reflected to the communication partner
 859  *
 860  * This function terminates an IUCV path.
 861  *
 862  * Returns the result from the CP IUCV call.
 863  */
 864 int iucv_path_sever(struct iucv_path *path, u8 userdata[16])
 865 {
 866         int rc;
 867
 868
 869         preempt_disable();
 870         if (iucv_tasklet_cpu != smp_processor_id())
 871                 spin_lock_bh(&iucv_table_lock);
 872         rc = iucv_sever_pathid(path->pathid, userdata);
 873         if (!rc) {
 874                 iucv_path_table[path->pathid] = NULL;
 875                 list_del_init(&path->list);
 876                 iucv_cleanup_pathid(path->pathid);
 877         }
 878         if (iucv_tasklet_cpu != smp_processor_id())
 879                 spin_unlock_bh(&iucv_table_lock);
 880         preempt_enable();
 881         return rc;
 882 }
 883
 884 /**
 885  * iucv_message_purge
 886  * @path: address of iucv path structure
 887  * @msg: address of iucv msg structure
 888  * @srccls: source class of message
 889  *
 890  * Cancels a message you have sent.
 891  *
 892  * Returns the result from the CP IUCV call.
 893  */
 894 int iucv_message_purge(struct iucv_path *path, struct iucv_message *msg,
 895                        u32 srccls)
 896 {
 897         union iucv_param *parm;
 898         int rc;
 899
 900         local_bh_disable();
 901         parm = percpu_ptr(iucv_param, smp_processor_id());
 902         memset(parm, 0, sizeof(union iucv_param));
 903         parm->purge.ippathid = path->pathid;
 904         parm->purge.ipmsgid = msg->id;
 905         parm->purge.ipsrccls = srccls;
 906         parm->purge.ipflags1 = IUCV_IPSRCCLS | IUCV_IPFGMID | IUCV_IPFGPID;
 907         rc = iucv_call_b2f0(IUCV_PURGE, parm);
 908         if (!rc) {
 909                 msg->audit = (*(u32 *) &parm->purge.ipaudit) >> 8;
 910                 msg->tag = parm->purge.ipmsgtag;
 911         }
 912         local_bh_enable();
 913         return rc;
 914 }
 915
 916 /**
 917  * iucv_message_receive
 918  * @path: address of iucv path structure
 919  * @msg: address of iucv msg structure
 920  * @flags: how the message is received (IUCV_IPBUFLST)
 921  * @buffer: address of data buffer or address of struct iucv_array
 922  * @size: length of data buffer
 923  * @residual:
 924  *
 925  * This function receives messages that are being sent to you over
 926  * established paths. This function will deal with RMDATA messages
 927  * embedded in struct iucv_message as well.
 928  *
 929  * Returns the result from the CP IUCV call.
 930  */
 931 int iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
 932                          u8 flags, void *buffer, size_t size, size_t *residual)
 933 {
 934         union iucv_param *parm;
 935         struct iucv_array *array;
 936         u8 *rmmsg;
 937         size_t copy;
 938         int rc;
 939
 940         if (msg->flags & IUCV_IPRMDATA) {
 941                 /*
 942                  * Message is 8 bytes long and has been stored to the
 943                  * message descriptor itself.
 944                  */
 945                 rc = (size < 8) ? 5 : 0;
 946                 if (residual)
 947                         *residual = abs(size - 8);
 948                 rmmsg = msg->rmmsg;
 949                 if (flags & IUCV_IPBUFLST) {
 950                         /* Copy to struct iucv_array. */
 951                         size = (size < 8) ? size : 8;
 952                         for (array = buffer; size > 0; array++) {
 953                                 copy = min_t(size_t, size, array->length);
 954                                 memcpy((u8 *)(addr_t) array->address,
 955                                        rmmsg, copy);
 956                                 rmmsg += copy;
 957                                 size -= copy;
 958                         }
 959                 } else {
 960                         /* Copy to direct buffer. */
 961                         memcpy(buffer, rmmsg, min_t(size_t, size, 8));
 962                 }
 963                 return 0;
 964         }
 965
 966         local_bh_disable();
 967         parm = percpu_ptr(iucv_param, smp_processor_id());
 968         memset(parm, 0, sizeof(union iucv_param));
 969         parm->db.ipbfadr1 = (u32)(addr_t) buffer;
 970         parm->db.ipbfln1f = (u32) size;
 971         parm->db.ipmsgid = msg->id;
 972         parm->db.ippathid = path->pathid;
 973         parm->db.iptrgcls = msg->class;
 974         parm->db.ipflags1 = (flags | IUCV_IPFGPID |
 975                              IUCV_IPFGMID | IUCV_IPTRGCLS);
 976         rc = iucv_call_b2f0(IUCV_RECEIVE, parm);
 977         if (!rc || rc == 5) {
 978                 msg->flags = parm->db.ipflags1;
 979                 if (residual)
 980                         *residual = parm->db.ipbfln1f;
 981         }
 982         local_bh_enable();
 983         return rc;
 984 }
 985
 986 /**
 987  * iucv_message_reject
 988  * @path: address of iucv path structure
 989  * @msg: address of iucv msg structure
 990  *
 991  * The reject function refuses a specified message. Between the time you
 992  * are notified of a message and the time that you complete the message,
 993  * the message may be rejected.
 994  *
 995  * Returns the result from the CP IUCV call.
 996  */
 997 int iucv_message_reject(struct iucv_path *path, struct iucv_message *msg)
 998 {
 999         union iucv_param *parm;
1000         int rc;
1001
1002         local_bh_disable();
1003         parm = percpu_ptr(iucv_param, smp_processor_id());
1004         memset(parm, 0, sizeof(union iucv_param));
1005         parm->db.ippathid = path->pathid;
1006         parm->db.ipmsgid = msg->id;
1007         parm->db.iptrgcls = msg->class;
1008         parm->db.ipflags1 = (IUCV_IPTRGCLS | IUCV_IPFGMID | IUCV_IPFGPID);
1009         rc = iucv_call_b2f0(IUCV_REJECT, parm);
1010         local_bh_enable();
1011         return rc;
1012 }
1013
1014 /**
1015  * iucv_message_reply
1016  * @path: address of iucv path structure
1017  * @msg: address of iucv msg structure
1018  * @flags: how the reply is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1019  * @reply: address of reply data buffer or address of struct iucv_array
1020  * @size: length of reply data buffer
1021  *
1022  * This function responds to the two-way messages that you receive. You
1023  * must identify completely the message to which you wish to reply. ie,
1024  * pathid, msgid, and trgcls. Prmmsg signifies the data is moved into
1025  * the parameter list.
1026  *
1027  * Returns the result from the CP IUCV call.
1028  */
1029 int iucv_message_reply(struct iucv_path *path, struct iucv_message *msg,
1030                        u8 flags, void *reply, size_t size)
1031 {
1032         union iucv_param *parm;
1033         int rc;
1034
1035         local_bh_disable();
1036         parm = percpu_ptr(iucv_param, smp_processor_id());
1037         memset(parm, 0, sizeof(union iucv_param));
1038         if (flags & IUCV_IPRMDATA) {
1039                 parm->dpl.ippathid = path->pathid;
1040                 parm->dpl.ipflags1 = flags;
1041                 parm->dpl.ipmsgid = msg->id;
1042                 parm->dpl.iptrgcls = msg->class;
1043                 memcpy(parm->dpl.iprmmsg, reply, min_t(size_t, size, 8));
1044         } else {
1045                 parm->db.ipbfadr1 = (u32)(addr_t) reply;
1046                 parm->db.ipbfln1f = (u32) size;
1047                 parm->db.ippathid = path->pathid;
1048                 parm->db.ipflags1 = flags;
1049                 parm->db.ipmsgid = msg->id;
1050                 parm->db.iptrgcls = msg->class;
1051         }
1052         rc = iucv_call_b2f0(IUCV_REPLY, parm);
1053         local_bh_enable();
1054         return rc;
1055 }
1056
1057 /**
1058  * iucv_message_send
1059  * @path: address of iucv path structure
1060  * @msg: address of iucv msg structure
1061  * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1062  * @srccls: source class of message
1063  * @buffer: address of send buffer or address of struct iucv_array
1064  * @size: length of send buffer
1065  *
1066  * This function transmits data to another application. Data to be
1067  * transmitted is in a buffer and this is a one-way message and the
1068  * receiver will not reply to the message.
1069  *
1070  * Returns the result from the CP IUCV call.
1071  */
1072 int iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
1073                       u8 flags, u32 srccls, void *buffer, size_t size)
1074 {
1075         union iucv_param *parm;
1076         int rc;
1077
1078         local_bh_disable();
1079         parm = percpu_ptr(iucv_param, smp_processor_id());
1080         memset(parm, 0, sizeof(union iucv_param));
1081         if (flags & IUCV_IPRMDATA) {
1082                 /* Message of 8 bytes can be placed into the parameter list. */
1083                 parm->dpl.ippathid = path->pathid;
1084                 parm->dpl.ipflags1 = flags | IUCV_IPNORPY;
1085                 parm->dpl.iptrgcls = msg->class;
1086                 parm->dpl.ipsrccls = srccls;
1087                 parm->dpl.ipmsgtag = msg->tag;
1088                 memcpy(parm->dpl.iprmmsg, buffer, 8);
1089         } else {
1090                 parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1091                 parm->db.ipbfln1f = (u32) size;
1092                 parm->db.ippathid = path->pathid;
1093                 parm->db.ipflags1 = flags | IUCV_IPNORPY;
1094                 parm->db.iptrgcls = msg->class;
1095                 parm->db.ipsrccls = srccls;
1096                 parm->db.ipmsgtag = msg->tag;
1097         }
1098         rc = iucv_call_b2f0(IUCV_SEND, parm);
1099         if (!rc)
1100                 msg->id = parm->db.ipmsgid;
1101         local_bh_enable();
1102         return rc;
1103 }
1104
1105 /**
1106  * iucv_message_send2way
1107  * @path: address of iucv path structure
1108  * @msg: address of iucv msg structure
1109  * @flags: how the message is sent and the reply is received
1110  *         (IUCV_IPRMDATA, IUCV_IPBUFLST, IUCV_IPPRTY, IUCV_ANSLST)
1111  * @srccls: source class of message
1112  * @buffer: address of send buffer or address of struct iucv_array
1113  * @size: length of send buffer
1114  * @ansbuf: address of answer buffer or address of struct iucv_array
1115  * @asize: size of reply buffer
1116  *
1117  * This function transmits data to another application. Data to be
1118  * transmitted is in a buffer. The receiver of the send is expected to
1119  * reply to the message and a buffer is provided into which IUCV moves
1120  * the reply to this message.
1121  *
1122  * Returns the result from the CP IUCV call.
1123  */
1124 int iucv_message_send2way(struct iucv_path *path, struct iucv_message *msg,
1125                           u8 flags, u32 srccls, void *buffer, size_t size,
1126                           void *answer, size_t asize, size_t *residual)
1127 {
1128         union iucv_param *parm;
1129         int rc;
1130
1131         local_bh_disable();
1132         parm = percpu_ptr(iucv_param, smp_processor_id());
1133         memset(parm, 0, sizeof(union iucv_param));
1134         if (flags & IUCV_IPRMDATA) {
1135                 parm->dpl.ippathid = path->pathid;
1136                 parm->dpl.ipflags1 = path->flags;       /* priority message */
1137                 parm->dpl.iptrgcls = msg->class;
1138                 parm->dpl.ipsrccls = srccls;
1139                 parm->dpl.ipmsgtag = msg->tag;
1140                 parm->dpl.ipbfadr2 = (u32)(addr_t) answer;
1141                 parm->dpl.ipbfln2f = (u32) asize;
1142                 memcpy(parm->dpl.iprmmsg, buffer, 8);
1143         } else {
1144                 parm->db.ippathid = path->pathid;
1145                 parm->db.ipflags1 = path->flags;        /* priority message */
1146                 parm->db.iptrgcls = msg->class;
1147                 parm->db.ipsrccls = srccls;
1148                 parm->db.ipmsgtag = msg->tag;
1149                 parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1150                 parm->db.ipbfln1f = (u32) size;
1151                 parm->db.ipbfadr2 = (u32)(addr_t) answer;
1152                 parm->db.ipbfln2f = (u32) asize;
1153         }
1154         rc = iucv_call_b2f0(IUCV_SEND, parm);
1155         if (!rc)
1156                 msg->id = parm->db.ipmsgid;
1157         local_bh_enable();
1158         return rc;
1159 }
1160
1161 /**
1162  * iucv_path_pending
1163  * @data: Pointer to external interrupt buffer
1164  *
1165  * Process connection pending work item. Called from tasklet while holding
1166  * iucv_table_lock.
1167  */
1168 struct iucv_path_pending {
1169         u16 ippathid;
1170         u8  ipflags1;
1171         u8  iptype;
1172         u16 ipmsglim;
1173         u16 res1;
1174         u8  ipvmid[8];
1175         u8  ipuser[16];
1176         u32 res3;
1177         u8  ippollfg;
1178         u8  res4[3];
1179 } __attribute__ ((packed));
1180
1181 static void iucv_path_pending(struct iucv_irq_data *data)
1182 {
1183         struct iucv_path_pending *ipp = (void *) data;
1184         struct iucv_handler *handler;
1185         struct iucv_path *path;
1186         char *error;
1187
1188         BUG_ON(iucv_path_table[ipp->ippathid]);
1189         /* New pathid, handler found. Create a new path struct. */
1190         error = iucv_error_no_memory;
1191         path = iucv_path_alloc(ipp->ipmsglim, ipp->ipflags1, GFP_ATOMIC);
1192         if (!path)
1193                 goto out_sever;
1194         path->pathid = ipp->ippathid;
1195         iucv_path_table[path->pathid] = path;
1196         EBCASC(ipp->ipvmid, 8);
1197
1198         /* Call registered handler until one is found that wants the path. */
1199         list_for_each_entry(handler, &iucv_handler_list, list) {
1200                 if (!handler->path_pending)
1201                         continue;
1202                 /*
1203                  * Add path to handler to allow a call to iucv_path_sever
1204                  * inside the path_pending function. If the handler returns
1205                  * an error remove the path from the handler again.
1206                  */
1207                 list_add(&path->list, &handler->paths);
1208                 path->handler = handler;
1209                 if (!handler->path_pending(path, ipp->ipvmid, ipp->ipuser))
1210                         return;
1211                 list_del(&path->list);
1212                 path->handler = NULL;
1213         }
1214         /* No handler wanted the path. */
1215         iucv_path_table[path->pathid] = NULL;
1216         iucv_path_free(path);
1217         error = iucv_error_no_listener;
1218 out_sever:
1219         iucv_sever_pathid(ipp->ippathid, error);
1220 }
1221
1222 /**
1223  * iucv_path_complete
1224  * @data: Pointer to external interrupt buffer
1225  *
1226  * Process connection complete work item. Called from tasklet while holding
1227  * iucv_table_lock.
1228  */
1229 struct iucv_path_complete {
1230         u16 ippathid;
1231         u8  ipflags1;
1232         u8  iptype;
1233         u16 ipmsglim;
1234         u16 res1;
1235         u8  res2[8];
1236         u8  ipuser[16];
1237         u32 res3;
1238         u8  ippollfg;
1239         u8  res4[3];
1240 } __attribute__ ((packed));
1241
1242 static void iucv_path_complete(struct iucv_irq_data *data)
1243 {
1244         struct iucv_path_complete *ipc = (void *) data;
1245         struct iucv_path *path = iucv_path_table[ipc->ippathid];
1246
1247         BUG_ON(!path || !path->handler);
1248         if (path->handler->path_complete)
1249                 path->handler->path_complete(path, ipc->ipuser);
1250 }
1251
1252 /**
1253  * iucv_path_severed
1254  * @data: Pointer to external interrupt buffer
1255  *
1256  * Process connection severed work item. Called from tasklet while holding
1257  * iucv_table_lock.
1258  */
1259 struct iucv_path_severed {
1260         u16 ippathid;
1261         u8  res1;
1262         u8  iptype;
1263         u32 res2;
1264         u8  res3[8];
1265         u8  ipuser[16];
1266         u32 res4;
1267         u8  ippollfg;
1268         u8  res5[3];
1269 } __attribute__ ((packed));
1270
1271 static void iucv_path_severed(struct iucv_irq_data *data)
1272 {
1273         struct iucv_path_severed *ips = (void *) data;
1274         struct iucv_path *path = iucv_path_table[ips->ippathid];
1275
1276         BUG_ON(!path || !path->handler);
1277         if (path->handler->path_severed)
1278                 path->handler->path_severed(path, ips->ipuser);
1279         else {
1280                 iucv_sever_pathid(path->pathid, NULL);
1281                 iucv_path_table[path->pathid] = NULL;
1282                 list_del_init(&path->list);
1283                 iucv_cleanup_pathid(path->pathid);
1284                 iucv_path_free(path);
1285         }
1286 }
1287
1288 /**
1289  * iucv_path_quiesced
1290  * @data: Pointer to external interrupt buffer
1291  *
1292  * Process connection quiesced work item. Called from tasklet while holding
1293  * iucv_table_lock.
1294  */
1295 struct iucv_path_quiesced {
1296         u16 ippathid;
1297         u8  res1;
1298         u8  iptype;
1299         u32 res2;
1300         u8  res3[8];
1301         u8  ipuser[16];
1302         u32 res4;
1303         u8  ippollfg;
1304         u8  res5[3];
1305 } __attribute__ ((packed));
1306
1307 static void iucv_path_quiesced(struct iucv_irq_data *data)
1308 {
1309         struct iucv_path_quiesced *ipq = (void *) data;
1310         struct iucv_path *path = iucv_path_table[ipq->ippathid];
1311
1312         BUG_ON(!path || !path->handler);
1313         if (path->handler->path_quiesced)
1314                 path->handler->path_quiesced(path, ipq->ipuser);
1315 }
1316
1317 /**
1318  * iucv_path_resumed
1319  * @data: Pointer to external interrupt buffer
1320  *
1321  * Process connection resumed work item. Called from tasklet while holding
1322  * iucv_table_lock.
1323  */
1324 struct iucv_path_resumed {
1325         u16 ippathid;
1326         u8  res1;
1327         u8  iptype;
1328         u32 res2;
1329         u8  res3[8];
1330         u8  ipuser[16];
1331         u32 res4;
1332         u8  ippollfg;
1333         u8  res5[3];
1334 } __attribute__ ((packed));
1335
1336 static void iucv_path_resumed(struct iucv_irq_data *data)
1337 {
1338         struct iucv_path_resumed *ipr = (void *) data;
1339         struct iucv_path *path = iucv_path_table[ipr->ippathid];
1340
1341         BUG_ON(!path || !path->handler);
1342         if (path->handler->path_resumed)
1343                 path->handler->path_resumed(path, ipr->ipuser);
1344 }
1345
1346 /**
1347  * iucv_message_complete
1348  * @data: Pointer to external interrupt buffer
1349  *
1350  * Process message complete work item. Called from tasklet while holding
1351  * iucv_table_lock.
1352  */
1353 struct iucv_message_complete {
1354         u16 ippathid;
1355         u8  ipflags1;
1356         u8  iptype;
1357         u32 ipmsgid;
1358         u32 ipaudit;
1359         u8  iprmmsg[8];
1360         u32 ipsrccls;
1361         u32 ipmsgtag;
1362         u32 res;
1363         u32 ipbfln2f;
1364         u8  ippollfg;
1365         u8  res2[3];
1366 } __attribute__ ((packed));
1367
1368 static void iucv_message_complete(struct iucv_irq_data *data)
1369 {
1370         struct iucv_message_complete *imc = (void *) data;
1371         struct iucv_path *path = iucv_path_table[imc->ippathid];
1372         struct iucv_message msg;
1373
1374         BUG_ON(!path || !path->handler);
1375         if (path->handler->message_complete) {
1376                 msg.flags = imc->ipflags1;
1377                 msg.id = imc->ipmsgid;
1378                 msg.audit = imc->ipaudit;
1379                 memcpy(msg.rmmsg, imc->iprmmsg, 8);
1380                 msg.class = imc->ipsrccls;
1381                 msg.tag = imc->ipmsgtag;
1382                 msg.length = imc->ipbfln2f;
1383                 path->handler->message_complete(path, &msg);
1384         }
1385 }
1386
1387 /**
1388  * iucv_message_pending
1389  * @data: Pointer to external interrupt buffer
1390  *
1391  * Process message pending work item. Called from tasklet while holding
1392  * iucv_table_lock.
1393  */
1394 struct iucv_message_pending {
1395         u16 ippathid;
1396         u8  ipflags1;
1397         u8  iptype;
1398         u32 ipmsgid;
1399         u32 iptrgcls;
1400         union {
1401                 u32 iprmmsg1_u32;
1402                 u8  iprmmsg1[4];
1403         } ln1msg1;
1404         union {
1405                 u32 ipbfln1f;
1406                 u8  iprmmsg2[4];
1407         } ln1msg2;
1408         u32 res1[3];
1409         u32 ipbfln2f;
1410         u8  ippollfg;
1411         u8  res2[3];
1412 } __attribute__ ((packed));
1413
1414 static void iucv_message_pending(struct iucv_irq_data *data)
1415 {
1416         struct iucv_message_pending *imp = (void *) data;
1417         struct iucv_path *path = iucv_path_table[imp->ippathid];
1418         struct iucv_message msg;
1419
1420         BUG_ON(!path || !path->handler);
1421         if (path->handler->message_pending) {
1422                 msg.flags = imp->ipflags1;
1423                 msg.id = imp->ipmsgid;
1424                 msg.class = imp->iptrgcls;
1425                 if (imp->ipflags1 & IUCV_IPRMDATA) {
1426                         memcpy(msg.rmmsg, imp->ln1msg1.iprmmsg1, 8);
1427                         msg.length = 8;
1428                 } else
1429                         msg.length = imp->ln1msg2.ipbfln1f;
1430                 msg.reply_size = imp->ipbfln2f;
1431                 path->handler->message_pending(path, &msg);
1432         }
1433 }
1434
1435 /**
1436  * iucv_tasklet_handler:
1437  *
1438  * This tasklet loops over the queue of irq buffers created by
1439  * iucv_external_interrupt, calls the appropriate action handler
1440  * and then frees the buffer.
1441  */
1442 static void iucv_tasklet_handler(unsigned long ignored)
1443 {
1444         typedef void iucv_irq_fn(struct iucv_irq_data *);
1445         static iucv_irq_fn *irq_fn[] = {
1446                 [0x01] = iucv_path_pending,
1447                 [0x02] = iucv_path_complete,
1448                 [0x03] = iucv_path_severed,
1449                 [0x04] = iucv_path_quiesced,
1450                 [0x05] = iucv_path_resumed,
1451                 [0x06] = iucv_message_complete,
1452                 [0x07] = iucv_message_complete,
1453                 [0x08] = iucv_message_pending,
1454                 [0x09] = iucv_message_pending,
1455         };
1456         struct iucv_work *p;
1457
1458         /* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1459         spin_lock(&iucv_table_lock);
1460         iucv_tasklet_cpu = smp_processor_id();
1461
1462         spin_lock_irq(&iucv_work_lock);
1463         while (!list_empty(&iucv_work_queue)) {
1464                 p = list_entry(iucv_work_queue.next, struct iucv_work, list);
1465                 list_del_init(&p->list);
1466                 spin_unlock_irq(&iucv_work_lock);
1467                 irq_fn[p->data.iptype](&p->data);
1468                 kfree(p);
1469                 spin_lock_irq(&iucv_work_lock);
1470         }
1471         spin_unlock_irq(&iucv_work_lock);
1472
1473         iucv_tasklet_cpu = -1;
1474         spin_unlock(&iucv_table_lock);
1475 }
1476
1477 /**
1478  * iucv_external_interrupt
1479  * @code: irq code
1480  *
1481  * Handles external interrupts coming in from CP.
1482  * Places the interrupt buffer on a queue and schedules iucv_tasklet_handler().
1483  */
1484 static void iucv_external_interrupt(u16 code)
1485 {
1486         struct iucv_irq_data *p;
1487         struct iucv_work *work;
1488
1489         p = percpu_ptr(iucv_irq_data, smp_processor_id());
1490         if (p->ippathid >= iucv_max_pathid) {
1491                 printk(KERN_WARNING "iucv_do_int: Got interrupt with "
1492                        "pathid %d > max_connections (%ld)\n",
1493                        p->ippathid, iucv_max_pathid - 1);
1494                 iucv_sever_pathid(p->ippathid, iucv_error_no_listener);
1495                 return;
1496         }
1497         if (p->iptype  < 0x01 || p->iptype > 0x09) {
1498                 printk(KERN_ERR "iucv_do_int: unknown iucv interrupt\n");
1499                 return;
1500         }
1501         work = kmalloc(sizeof(struct iucv_work), GFP_ATOMIC);
1502         if (!work) {
1503                 printk(KERN_WARNING "iucv_external_interrupt: out of memory\n");
1504                 return;
1505         }
1506         memcpy(&work->data, p, sizeof(work->data));
1507         spin_lock(&iucv_work_lock);
1508         list_add_tail(&work->list, &iucv_work_queue);
1509         spin_unlock(&iucv_work_lock);
1510         tasklet_schedule(&iucv_tasklet);
1511 }
1512
1513 /**
1514  * iucv_init
1515  *
1516  * Allocates and initializes various data structures.
1517  */
1518 static int iucv_init(void)
1519 {
1520         int rc;
1521
1522         if (!MACHINE_IS_VM) {
1523                 rc = -EPROTONOSUPPORT;
1524                 goto out;
1525         }
1526         rc = iucv_query_maxconn();
1527         if (rc)
1528                 goto out;
1529         rc = register_external_interrupt (0x4000, iucv_external_interrupt);
1530         if (rc)
1531                 goto out;
1532         rc = bus_register(&iucv_bus);
1533         if (rc)
1534                 goto out_int;
1535         iucv_root = s390_root_dev_register("iucv");
1536         if (IS_ERR(iucv_root)) {
1537                 rc = PTR_ERR(iucv_root);
1538                 goto out_bus;
1539         }
1540         /* Note: GFP_DMA used used to get memory below 2G */
1541         iucv_irq_data = percpu_alloc(sizeof(struct iucv_irq_data),
1542                                      GFP_KERNEL|GFP_DMA);
1543         if (!iucv_irq_data) {
1544                 rc = -ENOMEM;
1545                 goto out_root;
1546         }
1547         /* Allocate parameter blocks. */
1548         iucv_param = percpu_alloc(sizeof(union iucv_param),
1549                                   GFP_KERNEL|GFP_DMA);
1550         if (!iucv_param) {
1551                 rc = -ENOMEM;
1552                 goto out_extint;
1553         }
1554         register_hotcpu_notifier(&iucv_cpu_notifier);
1555         ASCEBC(iucv_error_no_listener, 16);
1556         ASCEBC(iucv_error_no_memory, 16);
1557         ASCEBC(iucv_error_pathid, 16);
1558         iucv_available = 1;
1559         return 0;
1560
1561 out_extint:
1562         percpu_free(iucv_irq_data);
1563 out_root:
1564         s390_root_dev_unregister(iucv_root);
1565 out_bus:
1566         bus_unregister(&iucv_bus);
1567 out_int:
1568         unregister_external_interrupt(0x4000, iucv_external_interrupt);
1569 out:
1570         return rc;
1571 }
1572
1573 /**
1574  * iucv_exit
1575  *
1576  * Frees everything allocated from iucv_init.
1577  */
1578 static void iucv_exit(void)
1579 {
1580         struct iucv_work *p, *n;
1581
1582         spin_lock_irq(&iucv_work_lock);
1583         list_for_each_entry_safe(p, n, &iucv_work_queue, list)
1584                 kfree(p);
1585         spin_unlock_irq(&iucv_work_lock);
1586         unregister_hotcpu_notifier(&iucv_cpu_notifier);
1587         percpu_free(iucv_param);
1588         percpu_free(iucv_irq_data);
1589         s390_root_dev_unregister(iucv_root);
1590         bus_unregister(&iucv_bus);
1591         unregister_external_interrupt(0x4000, iucv_external_interrupt);
1592 }
1593
1594 subsys_initcall(iucv_init);
1595 module_exit(iucv_exit);
1596
1597 /**
1598  * Export all public stuff
1599  */
1600 EXPORT_SYMBOL (iucv_bus);
1601 EXPORT_SYMBOL (iucv_root);
1602 EXPORT_SYMBOL (iucv_register);
1603 EXPORT_SYMBOL (iucv_unregister);
1604 EXPORT_SYMBOL (iucv_path_accept);
1605 EXPORT_SYMBOL (iucv_path_connect);
1606 EXPORT_SYMBOL (iucv_path_quiesce);
1607 EXPORT_SYMBOL (iucv_path_sever);
1608 EXPORT_SYMBOL (iucv_message_purge);
1609 EXPORT_SYMBOL (iucv_message_receive);
1610 EXPORT_SYMBOL (iucv_message_reject);
1611 EXPORT_SYMBOL (iucv_message_reply);
1612 EXPORT_SYMBOL (iucv_message_send);
1613 EXPORT_SYMBOL (iucv_message_send2way);
1614
1615 MODULE_AUTHOR("(C) 2001 IBM Corp. by Fritz Elfert (felfert@millenux.com)");
1616 MODULE_DESCRIPTION("Linux for S/390 IUCV lowlevel driver");
1617 MODULE_LICENSE("GPL");