net/iucv/iucv.c

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