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 const 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[9];
  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: array of pointers to 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  * @command: identifier of IUCV call to CP.
 281  * @parm: pointer to a struct iucv_parm block
 282  *
 283  * Calls CP to execute IUCV commands.
 284  *
 285  * Returns the result of the CP IUCV call.
 286  */
 287 static inline int __iucv_call_b2f0(int command, union iucv_param *parm)
 288 {
 289         unsigned long reg1 = virt_to_phys(parm);
 290         int cc;
 291
 292         asm volatile(
 293                 "       lgr     0,%[reg0]\n"
 294                 "       lgr     1,%[reg1]\n"
 295                 "       .long   0xb2f01000\n"
 296                 "       ipm     %[cc]\n"
 297                 "       srl     %[cc],28\n"
 298                 : [cc] "=&d" (cc), "+m" (*parm)
 299                 : [reg0] "d" ((unsigned long)command),
 300                   [reg1] "d" (reg1)
 301                 : "cc", "0", "1");
 302         return cc;
 303 }
 304
 305 static inline int iucv_call_b2f0(int command, union iucv_param *parm)
 306 {
 307         int ccode;
 308
 309         ccode = __iucv_call_b2f0(command, parm);
 310         return ccode == 1 ? parm->ctrl.iprcode : ccode;
 311 }
 312
 313 /*
 314  * iucv_query_maxconn
 315  *
 316  * Determines the maximum number of connections that may be established.
 317  *
 318  * Returns the maximum number of connections or -EPERM is IUCV is not
 319  * available.
 320  */
 321 static int __iucv_query_maxconn(void *param, unsigned long *max_pathid)
 322 {
 323         unsigned long reg1 = virt_to_phys(param);
 324         int cc;
 325
 326         asm volatile (
 327                 "       lghi    0,%[cmd]\n"
 328                 "       lgr     1,%[reg1]\n"
 329                 "       .long   0xb2f01000\n"
 330                 "       ipm     %[cc]\n"
 331                 "       srl     %[cc],28\n"
 332                 "       lgr     %[reg1],1\n"
 333                 : [cc] "=&d" (cc), [reg1] "+&d" (reg1)
 334                 : [cmd] "K" (IUCV_QUERY)
 335                 : "cc", "0", "1");
 336         *max_pathid = reg1;
 337         return cc;
 338 }
 339
 340 static int iucv_query_maxconn(void)
 341 {
 342         unsigned long max_pathid;
 343         void *param;
 344         int ccode;
 345
 346         param = kzalloc(sizeof(union iucv_param), GFP_KERNEL | GFP_DMA);
 347         if (!param)
 348                 return -ENOMEM;
 349         ccode = __iucv_query_maxconn(param, &max_pathid);
 350         if (ccode == 0)
 351                 iucv_max_pathid = max_pathid;
 352         kfree(param);
 353         return ccode ? -EPERM : 0;
 354 }
 355
 356 /**
 357  * iucv_allow_cpu
 358  * @data: unused
 359  *
 360  * Allow iucv interrupts on this cpu.
 361  */
 362 static void iucv_allow_cpu(void *data)
 363 {
 364         int cpu = smp_processor_id();
 365         union iucv_param *parm;
 366
 367         /*
 368          * Enable all iucv interrupts.
 369          * ipmask contains bits for the different interrupts
 370          *      0x80 - Flag to allow nonpriority message pending interrupts
 371          *      0x40 - Flag to allow priority message pending interrupts
 372          *      0x20 - Flag to allow nonpriority message completion interrupts
 373          *      0x10 - Flag to allow priority message completion interrupts
 374          *      0x08 - Flag to allow IUCV control interrupts
 375          */
 376         parm = iucv_param_irq[cpu];
 377         memset(parm, 0, sizeof(union iucv_param));
 378         parm->set_mask.ipmask = 0xf8;
 379         iucv_call_b2f0(IUCV_SETMASK, parm);
 380
 381         /*
 382          * Enable all iucv control interrupts.
 383          * ipmask contains bits for the different interrupts
 384          *      0x80 - Flag to allow pending connections interrupts
 385          *      0x40 - Flag to allow connection complete interrupts
 386          *      0x20 - Flag to allow connection severed interrupts
 387          *      0x10 - Flag to allow connection quiesced interrupts
 388          *      0x08 - Flag to allow connection resumed interrupts
 389          */
 390         memset(parm, 0, sizeof(union iucv_param));
 391         parm->set_mask.ipmask = 0xf8;
 392         iucv_call_b2f0(IUCV_SETCONTROLMASK, parm);
 393         /* Set indication that iucv interrupts are allowed for this cpu. */
 394         cpumask_set_cpu(cpu, &iucv_irq_cpumask);
 395 }
 396
 397 /**
 398  * iucv_block_cpu
 399  * @data: unused
 400  *
 401  * Block iucv interrupts on this cpu.
 402  */
 403 static void iucv_block_cpu(void *data)
 404 {
 405         int cpu = smp_processor_id();
 406         union iucv_param *parm;
 407
 408         /* Disable all iucv interrupts. */
 409         parm = iucv_param_irq[cpu];
 410         memset(parm, 0, sizeof(union iucv_param));
 411         iucv_call_b2f0(IUCV_SETMASK, parm);
 412
 413         /* Clear indication that iucv interrupts are allowed for this cpu. */
 414         cpumask_clear_cpu(cpu, &iucv_irq_cpumask);
 415 }
 416
 417 /**
 418  * iucv_declare_cpu
 419  * @data: unused
 420  *
 421  * Declare a interrupt buffer on this cpu.
 422  */
 423 static void iucv_declare_cpu(void *data)
 424 {
 425         int cpu = smp_processor_id();
 426         union iucv_param *parm;
 427         int rc;
 428
 429         if (cpumask_test_cpu(cpu, &iucv_buffer_cpumask))
 430                 return;
 431
 432         /* Declare interrupt buffer. */
 433         parm = iucv_param_irq[cpu];
 434         memset(parm, 0, sizeof(union iucv_param));
 435         parm->db.ipbfadr1 = virt_to_phys(iucv_irq_data[cpu]);
 436         rc = iucv_call_b2f0(IUCV_DECLARE_BUFFER, parm);
 437         if (rc) {
 438                 char *err = "Unknown";
 439                 switch (rc) {
 440                 case 0x03:
 441                         err = "Directory error";
 442                         break;
 443                 case 0x0a:
 444                         err = "Invalid length";
 445                         break;
 446                 case 0x13:
 447                         err = "Buffer already exists";
 448                         break;
 449                 case 0x3e:
 450                         err = "Buffer overlap";
 451                         break;
 452                 case 0x5c:
 453                         err = "Paging or storage error";
 454                         break;
 455                 }
 456                 pr_warn("Defining an interrupt buffer on CPU %i failed with 0x%02x (%s)\n",
 457                         cpu, rc, err);
 458                 return;
 459         }
 460
 461         /* Set indication that an iucv buffer exists for this cpu. */
 462         cpumask_set_cpu(cpu, &iucv_buffer_cpumask);
 463
 464         if (iucv_nonsmp_handler == 0 || cpumask_empty(&iucv_irq_cpumask))
 465                 /* Enable iucv interrupts on this cpu. */
 466                 iucv_allow_cpu(NULL);
 467         else
 468                 /* Disable iucv interrupts on this cpu. */
 469                 iucv_block_cpu(NULL);
 470 }
 471
 472 /**
 473  * iucv_retrieve_cpu
 474  * @data: unused
 475  *
 476  * Retrieve interrupt buffer on this cpu.
 477  */
 478 static void iucv_retrieve_cpu(void *data)
 479 {
 480         int cpu = smp_processor_id();
 481         union iucv_param *parm;
 482
 483         if (!cpumask_test_cpu(cpu, &iucv_buffer_cpumask))
 484                 return;
 485
 486         /* Block iucv interrupts. */
 487         iucv_block_cpu(NULL);
 488
 489         /* Retrieve interrupt buffer. */
 490         parm = iucv_param_irq[cpu];
 491         iucv_call_b2f0(IUCV_RETRIEVE_BUFFER, parm);
 492
 493         /* Clear indication that an iucv buffer exists for this cpu. */
 494         cpumask_clear_cpu(cpu, &iucv_buffer_cpumask);
 495 }
 496
 497 /*
 498  * iucv_setmask_mp
 499  *
 500  * Allow iucv interrupts on all cpus.
 501  */
 502 static void iucv_setmask_mp(void)
 503 {
 504         int cpu;
 505
 506         cpus_read_lock();
 507         for_each_online_cpu(cpu)
 508                 /* Enable all cpus with a declared buffer. */
 509                 if (cpumask_test_cpu(cpu, &iucv_buffer_cpumask) &&
 510                     !cpumask_test_cpu(cpu, &iucv_irq_cpumask))
 511                         smp_call_function_single(cpu, iucv_allow_cpu,
 512                                                  NULL, 1);
 513         cpus_read_unlock();
 514 }
 515
 516 /*
 517  * iucv_setmask_up
 518  *
 519  * Allow iucv interrupts on a single cpu.
 520  */
 521 static void iucv_setmask_up(void)
 522 {
 523         cpumask_t cpumask;
 524         int cpu;
 525
 526         /* Disable all cpu but the first in cpu_irq_cpumask. */
 527         cpumask_copy(&cpumask, &iucv_irq_cpumask);
 528         cpumask_clear_cpu(cpumask_first(&iucv_irq_cpumask), &cpumask);
 529         for_each_cpu(cpu, &cpumask)
 530                 smp_call_function_single(cpu, iucv_block_cpu, NULL, 1);
 531 }
 532
 533 /*
 534  * iucv_enable
 535  *
 536  * This function makes iucv ready for use. It allocates the pathid
 537  * table, declares an iucv interrupt buffer and enables the iucv
 538  * interrupts. Called when the first user has registered an iucv
 539  * handler.
 540  */
 541 static int iucv_enable(void)
 542 {
 543         size_t alloc_size;
 544         int cpu, rc;
 545
 546         cpus_read_lock();
 547         rc = -ENOMEM;
 548         alloc_size = iucv_max_pathid * sizeof(*iucv_path_table);
 549         iucv_path_table = kzalloc(alloc_size, GFP_KERNEL);
 550         if (!iucv_path_table)
 551                 goto out;
 552         /* Declare per cpu buffers. */
 553         rc = -EIO;
 554         for_each_online_cpu(cpu)
 555                 smp_call_function_single(cpu, iucv_declare_cpu, NULL, 1);
 556         if (cpumask_empty(&iucv_buffer_cpumask))
 557                 /* No cpu could declare an iucv buffer. */
 558                 goto out;
 559         cpus_read_unlock();
 560         return 0;
 561 out:
 562         kfree(iucv_path_table);
 563         iucv_path_table = NULL;
 564         cpus_read_unlock();
 565         return rc;
 566 }
 567
 568 /*
 569  * iucv_disable
 570  *
 571  * This function shuts down iucv. It disables iucv interrupts, retrieves
 572  * the iucv interrupt buffer and frees the pathid table. Called after the
 573  * last user unregister its iucv handler.
 574  */
 575 static void iucv_disable(void)
 576 {
 577         cpus_read_lock();
 578         on_each_cpu(iucv_retrieve_cpu, NULL, 1);
 579         kfree(iucv_path_table);
 580         iucv_path_table = NULL;
 581         cpus_read_unlock();
 582 }
 583
 584 static int iucv_cpu_dead(unsigned int cpu)
 585 {
 586         kfree(iucv_param_irq[cpu]);
 587         iucv_param_irq[cpu] = NULL;
 588         kfree(iucv_param[cpu]);
 589         iucv_param[cpu] = NULL;
 590         kfree(iucv_irq_data[cpu]);
 591         iucv_irq_data[cpu] = NULL;
 592         return 0;
 593 }
 594
 595 static int iucv_cpu_prepare(unsigned int cpu)
 596 {
 597         /* Note: GFP_DMA used to get memory below 2G */
 598         iucv_irq_data[cpu] = kmalloc_node(sizeof(struct iucv_irq_data),
 599                              GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
 600         if (!iucv_irq_data[cpu])
 601                 goto out_free;
 602
 603         /* Allocate parameter blocks. */
 604         iucv_param[cpu] = kmalloc_node(sizeof(union iucv_param),
 605                           GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
 606         if (!iucv_param[cpu])
 607                 goto out_free;
 608
 609         iucv_param_irq[cpu] = kmalloc_node(sizeof(union iucv_param),
 610                           GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
 611         if (!iucv_param_irq[cpu])
 612                 goto out_free;
 613
 614         return 0;
 615
 616 out_free:
 617         iucv_cpu_dead(cpu);
 618         return -ENOMEM;
 619 }
 620
 621 static int iucv_cpu_online(unsigned int cpu)
 622 {
 623         if (!iucv_path_table)
 624                 return 0;
 625         iucv_declare_cpu(NULL);
 626         return 0;
 627 }
 628
 629 static int iucv_cpu_down_prep(unsigned int cpu)
 630 {
 631         cpumask_t cpumask;
 632
 633         if (!iucv_path_table)
 634                 return 0;
 635
 636         cpumask_copy(&cpumask, &iucv_buffer_cpumask);
 637         cpumask_clear_cpu(cpu, &cpumask);
 638         if (cpumask_empty(&cpumask))
 639                 /* Can't offline last IUCV enabled cpu. */
 640                 return -EINVAL;
 641
 642         iucv_retrieve_cpu(NULL);
 643         if (!cpumask_empty(&iucv_irq_cpumask))
 644                 return 0;
 645         smp_call_function_single(cpumask_first(&iucv_buffer_cpumask),
 646                                  iucv_allow_cpu, NULL, 1);
 647         return 0;
 648 }
 649
 650 /**
 651  * iucv_sever_pathid
 652  * @pathid: path identification number.
 653  * @userdata: 16-bytes of user data.
 654  *
 655  * Sever an iucv path to free up the pathid. Used internally.
 656  */
 657 static int iucv_sever_pathid(u16 pathid, u8 *userdata)
 658 {
 659         union iucv_param *parm;
 660
 661         parm = iucv_param_irq[smp_processor_id()];
 662         memset(parm, 0, sizeof(union iucv_param));
 663         if (userdata)
 664                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 665         parm->ctrl.ippathid = pathid;
 666         return iucv_call_b2f0(IUCV_SEVER, parm);
 667 }
 668
 669 /**
 670  * __iucv_cleanup_queue
 671  * @dummy: unused dummy argument
 672  *
 673  * Nop function called via smp_call_function to force work items from
 674  * pending external iucv interrupts to the work queue.
 675  */
 676 static void __iucv_cleanup_queue(void *dummy)
 677 {
 678 }
 679
 680 /**
 681  * iucv_cleanup_queue
 682  *
 683  * Function called after a path has been severed to find all remaining
 684  * work items for the now stale pathid. The caller needs to hold the
 685  * iucv_table_lock.
 686  */
 687 static void iucv_cleanup_queue(void)
 688 {
 689         struct iucv_irq_list *p, *n;
 690
 691         /*
 692          * When a path is severed, the pathid can be reused immediately
 693          * on a iucv connect or a connection pending interrupt. Remove
 694          * all entries from the task queue that refer to a stale pathid
 695          * (iucv_path_table[ix] == NULL). Only then do the iucv connect
 696          * or deliver the connection pending interrupt. To get all the
 697          * pending interrupts force them to the work queue by calling
 698          * an empty function on all cpus.
 699          */
 700         smp_call_function(__iucv_cleanup_queue, NULL, 1);
 701         spin_lock_irq(&iucv_queue_lock);
 702         list_for_each_entry_safe(p, n, &iucv_task_queue, list) {
 703                 /* Remove stale work items from the task queue. */
 704                 if (iucv_path_table[p->data.ippathid] == NULL) {
 705                         list_del(&p->list);
 706                         kfree(p);
 707                 }
 708         }
 709         spin_unlock_irq(&iucv_queue_lock);
 710 }
 711
 712 /**
 713  * iucv_register:
 714  * @handler: address of iucv handler structure
 715  * @smp: != 0 indicates that the handler can deal with out of order messages
 716  *
 717  * Registers a driver with IUCV.
 718  *
 719  * Returns 0 on success, -ENOMEM if the memory allocation for the pathid
 720  * table failed, or -EIO if IUCV_DECLARE_BUFFER failed on all cpus.
 721  */
 722 int iucv_register(struct iucv_handler *handler, int smp)
 723 {
 724         int rc;
 725
 726         if (!iucv_available)
 727                 return -ENOSYS;
 728         mutex_lock(&iucv_register_mutex);
 729         if (!smp)
 730                 iucv_nonsmp_handler++;
 731         if (list_empty(&iucv_handler_list)) {
 732                 rc = iucv_enable();
 733                 if (rc)
 734                         goto out_mutex;
 735         } else if (!smp && iucv_nonsmp_handler == 1)
 736                 iucv_setmask_up();
 737         INIT_LIST_HEAD(&handler->paths);
 738
 739         spin_lock_bh(&iucv_table_lock);
 740         list_add_tail(&handler->list, &iucv_handler_list);
 741         spin_unlock_bh(&iucv_table_lock);
 742         rc = 0;
 743 out_mutex:
 744         mutex_unlock(&iucv_register_mutex);
 745         return rc;
 746 }
 747 EXPORT_SYMBOL(iucv_register);
 748
 749 /**
 750  * iucv_unregister
 751  * @handler:  address of iucv handler structure
 752  * @smp: != 0 indicates that the handler can deal with out of order messages
 753  *
 754  * Unregister driver from IUCV.
 755  */
 756 void iucv_unregister(struct iucv_handler *handler, int smp)
 757 {
 758         struct iucv_path *p, *n;
 759
 760         mutex_lock(&iucv_register_mutex);
 761         spin_lock_bh(&iucv_table_lock);
 762         /* Remove handler from the iucv_handler_list. */
 763         list_del_init(&handler->list);
 764         /* Sever all pathids still referring to the handler. */
 765         list_for_each_entry_safe(p, n, &handler->paths, list) {
 766                 iucv_sever_pathid(p->pathid, NULL);
 767                 iucv_path_table[p->pathid] = NULL;
 768                 list_del(&p->list);
 769                 iucv_path_free(p);
 770         }
 771         spin_unlock_bh(&iucv_table_lock);
 772         if (!smp)
 773                 iucv_nonsmp_handler--;
 774         if (list_empty(&iucv_handler_list))
 775                 iucv_disable();
 776         else if (!smp && iucv_nonsmp_handler == 0)
 777                 iucv_setmask_mp();
 778         mutex_unlock(&iucv_register_mutex);
 779 }
 780 EXPORT_SYMBOL(iucv_unregister);
 781
 782 static int iucv_reboot_event(struct notifier_block *this,
 783                              unsigned long event, void *ptr)
 784 {
 785         int i;
 786
 787         if (cpumask_empty(&iucv_irq_cpumask))
 788                 return NOTIFY_DONE;
 789
 790         cpus_read_lock();
 791         on_each_cpu_mask(&iucv_irq_cpumask, iucv_block_cpu, NULL, 1);
 792         preempt_disable();
 793         for (i = 0; i < iucv_max_pathid; i++) {
 794                 if (iucv_path_table[i])
 795                         iucv_sever_pathid(i, NULL);
 796         }
 797         preempt_enable();
 798         cpus_read_unlock();
 799         iucv_disable();
 800         return NOTIFY_DONE;
 801 }
 802
 803 static struct notifier_block iucv_reboot_notifier = {
 804         .notifier_call = iucv_reboot_event,
 805 };
 806
 807 /**
 808  * iucv_path_accept
 809  * @path: address of iucv path structure
 810  * @handler: address of iucv handler structure
 811  * @userdata: 16 bytes of data reflected to the communication partner
 812  * @private: private data passed to interrupt handlers for this path
 813  *
 814  * This function is issued after the user received a connection pending
 815  * external interrupt and now wishes to complete the IUCV communication path.
 816  *
 817  * Returns the result of the CP IUCV call.
 818  */
 819 int iucv_path_accept(struct iucv_path *path, struct iucv_handler *handler,
 820                      u8 *userdata, void *private)
 821 {
 822         union iucv_param *parm;
 823         int rc;
 824
 825         local_bh_disable();
 826         if (cpumask_empty(&iucv_buffer_cpumask)) {
 827                 rc = -EIO;
 828                 goto out;
 829         }
 830         /* Prepare parameter block. */
 831         parm = iucv_param[smp_processor_id()];
 832         memset(parm, 0, sizeof(union iucv_param));
 833         parm->ctrl.ippathid = path->pathid;
 834         parm->ctrl.ipmsglim = path->msglim;
 835         if (userdata)
 836                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 837         parm->ctrl.ipflags1 = path->flags;
 838
 839         rc = iucv_call_b2f0(IUCV_ACCEPT, parm);
 840         if (!rc) {
 841                 path->private = private;
 842                 path->msglim = parm->ctrl.ipmsglim;
 843                 path->flags = parm->ctrl.ipflags1;
 844         }
 845 out:
 846         local_bh_enable();
 847         return rc;
 848 }
 849 EXPORT_SYMBOL(iucv_path_accept);
 850
 851 /**
 852  * iucv_path_connect
 853  * @path: address of iucv path structure
 854  * @handler: address of iucv handler structure
 855  * @userid: 8-byte user identification
 856  * @system: 8-byte target system identification
 857  * @userdata: 16 bytes of data reflected to the communication partner
 858  * @private: private data passed to interrupt handlers for this path
 859  *
 860  * This function establishes an IUCV path. Although the connect may complete
 861  * successfully, you are not able to use the path until you receive an IUCV
 862  * Connection Complete external interrupt.
 863  *
 864  * Returns the result of the CP IUCV call.
 865  */
 866 int iucv_path_connect(struct iucv_path *path, struct iucv_handler *handler,
 867                       u8 *userid, u8 *system, u8 *userdata,
 868                       void *private)
 869 {
 870         union iucv_param *parm;
 871         int rc;
 872
 873         spin_lock_bh(&iucv_table_lock);
 874         iucv_cleanup_queue();
 875         if (cpumask_empty(&iucv_buffer_cpumask)) {
 876                 rc = -EIO;
 877                 goto out;
 878         }
 879         parm = iucv_param[smp_processor_id()];
 880         memset(parm, 0, sizeof(union iucv_param));
 881         parm->ctrl.ipmsglim = path->msglim;
 882         parm->ctrl.ipflags1 = path->flags;
 883         if (userid) {
 884                 memcpy(parm->ctrl.ipvmid, userid, sizeof(parm->ctrl.ipvmid));
 885                 ASCEBC(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
 886                 EBC_TOUPPER(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
 887         }
 888         if (system) {
 889                 memcpy(parm->ctrl.iptarget, system,
 890                        sizeof(parm->ctrl.iptarget));
 891                 ASCEBC(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
 892                 EBC_TOUPPER(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
 893         }
 894         if (userdata)
 895                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 896
 897         rc = iucv_call_b2f0(IUCV_CONNECT, parm);
 898         if (!rc) {
 899                 if (parm->ctrl.ippathid < iucv_max_pathid) {
 900                         path->pathid = parm->ctrl.ippathid;
 901                         path->msglim = parm->ctrl.ipmsglim;
 902                         path->flags = parm->ctrl.ipflags1;
 903                         path->handler = handler;
 904                         path->private = private;
 905                         list_add_tail(&path->list, &handler->paths);
 906                         iucv_path_table[path->pathid] = path;
 907                 } else {
 908                         iucv_sever_pathid(parm->ctrl.ippathid,
 909                                           iucv_error_pathid);
 910                         rc = -EIO;
 911                 }
 912         }
 913 out:
 914         spin_unlock_bh(&iucv_table_lock);
 915         return rc;
 916 }
 917 EXPORT_SYMBOL(iucv_path_connect);
 918
 919 /**
 920  * iucv_path_quiesce:
 921  * @path: address of iucv path structure
 922  * @userdata: 16 bytes of data reflected to the communication partner
 923  *
 924  * This function temporarily suspends incoming messages on an IUCV path.
 925  * You can later reactivate the path by invoking the iucv_resume function.
 926  *
 927  * Returns the result from the CP IUCV call.
 928  */
 929 int iucv_path_quiesce(struct iucv_path *path, u8 *userdata)
 930 {
 931         union iucv_param *parm;
 932         int rc;
 933
 934         local_bh_disable();
 935         if (cpumask_empty(&iucv_buffer_cpumask)) {
 936                 rc = -EIO;
 937                 goto out;
 938         }
 939         parm = iucv_param[smp_processor_id()];
 940         memset(parm, 0, sizeof(union iucv_param));
 941         if (userdata)
 942                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 943         parm->ctrl.ippathid = path->pathid;
 944         rc = iucv_call_b2f0(IUCV_QUIESCE, parm);
 945 out:
 946         local_bh_enable();
 947         return rc;
 948 }
 949 EXPORT_SYMBOL(iucv_path_quiesce);
 950
 951 /**
 952  * iucv_path_resume:
 953  * @path: address of iucv path structure
 954  * @userdata: 16 bytes of data reflected to the communication partner
 955  *
 956  * This function resumes incoming messages on an IUCV path that has
 957  * been stopped with iucv_path_quiesce.
 958  *
 959  * Returns the result from the CP IUCV call.
 960  */
 961 int iucv_path_resume(struct iucv_path *path, u8 *userdata)
 962 {
 963         union iucv_param *parm;
 964         int rc;
 965
 966         local_bh_disable();
 967         if (cpumask_empty(&iucv_buffer_cpumask)) {
 968                 rc = -EIO;
 969                 goto out;
 970         }
 971         parm = iucv_param[smp_processor_id()];
 972         memset(parm, 0, sizeof(union iucv_param));
 973         if (userdata)
 974                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 975         parm->ctrl.ippathid = path->pathid;
 976         rc = iucv_call_b2f0(IUCV_RESUME, parm);
 977 out:
 978         local_bh_enable();
 979         return rc;
 980 }
 981
 982 /**
 983  * iucv_path_sever
 984  * @path: address of iucv path structure
 985  * @userdata: 16 bytes of data reflected to the communication partner
 986  *
 987  * This function terminates an IUCV path.
 988  *
 989  * Returns the result from the CP IUCV call.
 990  */
 991 int iucv_path_sever(struct iucv_path *path, u8 *userdata)
 992 {
 993         int rc;
 994
 995         preempt_disable();
 996         if (cpumask_empty(&iucv_buffer_cpumask)) {
 997                 rc = -EIO;
 998                 goto out;
 999         }
1000         if (iucv_active_cpu != smp_processor_id())
1001                 spin_lock_bh(&iucv_table_lock);
1002         rc = iucv_sever_pathid(path->pathid, userdata);
1003         iucv_path_table[path->pathid] = NULL;
1004         list_del_init(&path->list);
1005         if (iucv_active_cpu != smp_processor_id())
1006                 spin_unlock_bh(&iucv_table_lock);
1007 out:
1008         preempt_enable();
1009         return rc;
1010 }
1011 EXPORT_SYMBOL(iucv_path_sever);
1012
1013 /**
1014  * iucv_message_purge
1015  * @path: address of iucv path structure
1016  * @msg: address of iucv msg structure
1017  * @srccls: source class of message
1018  *
1019  * Cancels a message you have sent.
1020  *
1021  * Returns the result from the CP IUCV call.
1022  */
1023 int iucv_message_purge(struct iucv_path *path, struct iucv_message *msg,
1024                        u32 srccls)
1025 {
1026         union iucv_param *parm;
1027         int rc;
1028
1029         local_bh_disable();
1030         if (cpumask_empty(&iucv_buffer_cpumask)) {
1031                 rc = -EIO;
1032                 goto out;
1033         }
1034         parm = iucv_param[smp_processor_id()];
1035         memset(parm, 0, sizeof(union iucv_param));
1036         parm->purge.ippathid = path->pathid;
1037         parm->purge.ipmsgid = msg->id;
1038         parm->purge.ipsrccls = srccls;
1039         parm->purge.ipflags1 = IUCV_IPSRCCLS | IUCV_IPFGMID | IUCV_IPFGPID;
1040         rc = iucv_call_b2f0(IUCV_PURGE, parm);
1041         if (!rc) {
1042                 msg->audit = (*(u32 *) &parm->purge.ipaudit) >> 8;
1043                 msg->tag = parm->purge.ipmsgtag;
1044         }
1045 out:
1046         local_bh_enable();
1047         return rc;
1048 }
1049 EXPORT_SYMBOL(iucv_message_purge);
1050
1051 /**
1052  * iucv_message_receive_iprmdata
1053  * @path: address of iucv path structure
1054  * @msg: address of iucv msg structure
1055  * @flags: how the message is received (IUCV_IPBUFLST)
1056  * @buffer: address of data buffer or address of struct iucv_array
1057  * @size: length of data buffer
1058  * @residual:
1059  *
1060  * Internal function used by iucv_message_receive and __iucv_message_receive
1061  * to receive RMDATA data stored in struct iucv_message.
1062  */
1063 static int iucv_message_receive_iprmdata(struct iucv_path *path,
1064                                          struct iucv_message *msg,
1065                                          u8 flags, void *buffer,
1066                                          size_t size, size_t *residual)
1067 {
1068         struct iucv_array *array;
1069         u8 *rmmsg;
1070         size_t copy;
1071
1072         /*
1073          * Message is 8 bytes long and has been stored to the
1074          * message descriptor itself.
1075          */
1076         if (residual)
1077                 *residual = abs(size - 8);
1078         rmmsg = msg->rmmsg;
1079         if (flags & IUCV_IPBUFLST) {
1080                 /* Copy to struct iucv_array. */
1081                 size = (size < 8) ? size : 8;
1082                 for (array = buffer; size > 0; array++) {
1083                         copy = min_t(size_t, size, array->length);
1084                         memcpy((u8 *)(addr_t) array->address,
1085                                 rmmsg, copy);
1086                         rmmsg += copy;
1087                         size -= copy;
1088                 }
1089         } else {
1090                 /* Copy to direct buffer. */
1091                 memcpy(buffer, rmmsg, min_t(size_t, size, 8));
1092         }
1093         return 0;
1094 }
1095
1096 /**
1097  * __iucv_message_receive
1098  * @path: address of iucv path structure
1099  * @msg: address of iucv msg structure
1100  * @flags: how the message is received (IUCV_IPBUFLST)
1101  * @buffer: address of data buffer or address of struct iucv_array
1102  * @size: length of data buffer
1103  * @residual:
1104  *
1105  * This function receives messages that are being sent to you over
1106  * established paths. This function will deal with RMDATA messages
1107  * embedded in struct iucv_message as well.
1108  *
1109  * Locking:     no locking
1110  *
1111  * Returns the result from the CP IUCV call.
1112  */
1113 int __iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
1114                            u8 flags, void *buffer, size_t size, size_t *residual)
1115 {
1116         union iucv_param *parm;
1117         int rc;
1118
1119         if (msg->flags & IUCV_IPRMDATA)
1120                 return iucv_message_receive_iprmdata(path, msg, flags,
1121                                                      buffer, size, residual);
1122         if (cpumask_empty(&iucv_buffer_cpumask))
1123                 return -EIO;
1124
1125         parm = iucv_param[smp_processor_id()];
1126         memset(parm, 0, sizeof(union iucv_param));
1127         parm->db.ipbfadr1 = (u32)virt_to_phys(buffer);
1128         parm->db.ipbfln1f = (u32) size;
1129         parm->db.ipmsgid = msg->id;
1130         parm->db.ippathid = path->pathid;
1131         parm->db.iptrgcls = msg->class;
1132         parm->db.ipflags1 = (flags | IUCV_IPFGPID |
1133                              IUCV_IPFGMID | IUCV_IPTRGCLS);
1134         rc = iucv_call_b2f0(IUCV_RECEIVE, parm);
1135         if (!rc || rc == 5) {
1136                 msg->flags = parm->db.ipflags1;
1137                 if (residual)
1138                         *residual = parm->db.ipbfln1f;
1139         }
1140         return rc;
1141 }
1142 EXPORT_SYMBOL(__iucv_message_receive);
1143
1144 /**
1145  * iucv_message_receive
1146  * @path: address of iucv path structure
1147  * @msg: address of iucv msg structure
1148  * @flags: how the message is received (IUCV_IPBUFLST)
1149  * @buffer: address of data buffer or address of struct iucv_array
1150  * @size: length of data buffer
1151  * @residual:
1152  *
1153  * This function receives messages that are being sent to you over
1154  * established paths. This function will deal with RMDATA messages
1155  * embedded in struct iucv_message as well.
1156  *
1157  * Locking:     local_bh_enable/local_bh_disable
1158  *
1159  * Returns the result from the CP IUCV call.
1160  */
1161 int iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
1162                          u8 flags, void *buffer, size_t size, size_t *residual)
1163 {
1164         int rc;
1165
1166         if (msg->flags & IUCV_IPRMDATA)
1167                 return iucv_message_receive_iprmdata(path, msg, flags,
1168                                                      buffer, size, residual);
1169         local_bh_disable();
1170         rc = __iucv_message_receive(path, msg, flags, buffer, size, residual);
1171         local_bh_enable();
1172         return rc;
1173 }
1174 EXPORT_SYMBOL(iucv_message_receive);
1175
1176 /**
1177  * iucv_message_reject
1178  * @path: address of iucv path structure
1179  * @msg: address of iucv msg structure
1180  *
1181  * The reject function refuses a specified message. Between the time you
1182  * are notified of a message and the time that you complete the message,
1183  * the message may be rejected.
1184  *
1185  * Returns the result from the CP IUCV call.
1186  */
1187 int iucv_message_reject(struct iucv_path *path, struct iucv_message *msg)
1188 {
1189         union iucv_param *parm;
1190         int rc;
1191
1192         local_bh_disable();
1193         if (cpumask_empty(&iucv_buffer_cpumask)) {
1194                 rc = -EIO;
1195                 goto out;
1196         }
1197         parm = iucv_param[smp_processor_id()];
1198         memset(parm, 0, sizeof(union iucv_param));
1199         parm->db.ippathid = path->pathid;
1200         parm->db.ipmsgid = msg->id;
1201         parm->db.iptrgcls = msg->class;
1202         parm->db.ipflags1 = (IUCV_IPTRGCLS | IUCV_IPFGMID | IUCV_IPFGPID);
1203         rc = iucv_call_b2f0(IUCV_REJECT, parm);
1204 out:
1205         local_bh_enable();
1206         return rc;
1207 }
1208 EXPORT_SYMBOL(iucv_message_reject);
1209
1210 /**
1211  * iucv_message_reply
1212  * @path: address of iucv path structure
1213  * @msg: address of iucv msg structure
1214  * @flags: how the reply is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1215  * @reply: address of reply data buffer or address of struct iucv_array
1216  * @size: length of reply data buffer
1217  *
1218  * This function responds to the two-way messages that you receive. You
1219  * must identify completely the message to which you wish to reply. ie,
1220  * pathid, msgid, and trgcls. Prmmsg signifies the data is moved into
1221  * the parameter list.
1222  *
1223  * Returns the result from the CP IUCV call.
1224  */
1225 int iucv_message_reply(struct iucv_path *path, struct iucv_message *msg,
1226                        u8 flags, void *reply, size_t size)
1227 {
1228         union iucv_param *parm;
1229         int rc;
1230
1231         local_bh_disable();
1232         if (cpumask_empty(&iucv_buffer_cpumask)) {
1233                 rc = -EIO;
1234                 goto out;
1235         }
1236         parm = iucv_param[smp_processor_id()];
1237         memset(parm, 0, sizeof(union iucv_param));
1238         if (flags & IUCV_IPRMDATA) {
1239                 parm->dpl.ippathid = path->pathid;
1240                 parm->dpl.ipflags1 = flags;
1241                 parm->dpl.ipmsgid = msg->id;
1242                 parm->dpl.iptrgcls = msg->class;
1243                 memcpy(parm->dpl.iprmmsg, reply, min_t(size_t, size, 8));
1244         } else {
1245                 parm->db.ipbfadr1 = (u32)virt_to_phys(reply);
1246                 parm->db.ipbfln1f = (u32) size;
1247                 parm->db.ippathid = path->pathid;
1248                 parm->db.ipflags1 = flags;
1249                 parm->db.ipmsgid = msg->id;
1250                 parm->db.iptrgcls = msg->class;
1251         }
1252         rc = iucv_call_b2f0(IUCV_REPLY, parm);
1253 out:
1254         local_bh_enable();
1255         return rc;
1256 }
1257 EXPORT_SYMBOL(iucv_message_reply);
1258
1259 /**
1260  * __iucv_message_send
1261  * @path: address of iucv path structure
1262  * @msg: address of iucv msg structure
1263  * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1264  * @srccls: source class of message
1265  * @buffer: address of send buffer or address of struct iucv_array
1266  * @size: length of send buffer
1267  *
1268  * This function transmits data to another application. Data to be
1269  * transmitted is in a buffer and this is a one-way message and the
1270  * receiver will not reply to the message.
1271  *
1272  * Locking:     no locking
1273  *
1274  * Returns the result from the CP IUCV call.
1275  */
1276 int __iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
1277                       u8 flags, u32 srccls, void *buffer, size_t size)
1278 {
1279         union iucv_param *parm;
1280         int rc;
1281
1282         if (cpumask_empty(&iucv_buffer_cpumask)) {
1283                 rc = -EIO;
1284                 goto out;
1285         }
1286         parm = iucv_param[smp_processor_id()];
1287         memset(parm, 0, sizeof(union iucv_param));
1288         if (flags & IUCV_IPRMDATA) {
1289                 /* Message of 8 bytes can be placed into the parameter list. */
1290                 parm->dpl.ippathid = path->pathid;
1291                 parm->dpl.ipflags1 = flags | IUCV_IPNORPY;
1292                 parm->dpl.iptrgcls = msg->class;
1293                 parm->dpl.ipsrccls = srccls;
1294                 parm->dpl.ipmsgtag = msg->tag;
1295                 memcpy(parm->dpl.iprmmsg, buffer, 8);
1296         } else {
1297                 parm->db.ipbfadr1 = (u32)virt_to_phys(buffer);
1298                 parm->db.ipbfln1f = (u32) size;
1299                 parm->db.ippathid = path->pathid;
1300                 parm->db.ipflags1 = flags | IUCV_IPNORPY;
1301                 parm->db.iptrgcls = msg->class;
1302                 parm->db.ipsrccls = srccls;
1303                 parm->db.ipmsgtag = msg->tag;
1304         }
1305         rc = iucv_call_b2f0(IUCV_SEND, parm);
1306         if (!rc)
1307                 msg->id = parm->db.ipmsgid;
1308 out:
1309         return rc;
1310 }
1311 EXPORT_SYMBOL(__iucv_message_send);
1312
1313 /**
1314  * iucv_message_send
1315  * @path: address of iucv path structure
1316  * @msg: address of iucv msg structure
1317  * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1318  * @srccls: source class of message
1319  * @buffer: address of send buffer or address of struct iucv_array
1320  * @size: length of send buffer
1321  *
1322  * This function transmits data to another application. Data to be
1323  * transmitted is in a buffer and this is a one-way message and the
1324  * receiver will not reply to the message.
1325  *
1326  * Locking:     local_bh_enable/local_bh_disable
1327  *
1328  * Returns the result from the CP IUCV call.
1329  */
1330 int iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
1331                       u8 flags, u32 srccls, void *buffer, size_t size)
1332 {
1333         int rc;
1334
1335         local_bh_disable();
1336         rc = __iucv_message_send(path, msg, flags, srccls, buffer, size);
1337         local_bh_enable();
1338         return rc;
1339 }
1340 EXPORT_SYMBOL(iucv_message_send);
1341
1342 /**
1343  * iucv_message_send2way
1344  * @path: address of iucv path structure
1345  * @msg: address of iucv msg structure
1346  * @flags: how the message is sent and the reply is received
1347  *         (IUCV_IPRMDATA, IUCV_IPBUFLST, IUCV_IPPRTY, IUCV_ANSLST)
1348  * @srccls: source class of message
1349  * @buffer: address of send buffer or address of struct iucv_array
1350  * @size: length of send buffer
1351  * @answer: address of answer buffer or address of struct iucv_array
1352  * @asize: size of reply buffer
1353  * @residual: ignored
1354  *
1355  * This function transmits data to another application. Data to be
1356  * transmitted is in a buffer. The receiver of the send is expected to
1357  * reply to the message and a buffer is provided into which IUCV moves
1358  * the reply to this message.
1359  *
1360  * Returns the result from the CP IUCV call.
1361  */
1362 int iucv_message_send2way(struct iucv_path *path, struct iucv_message *msg,
1363                           u8 flags, u32 srccls, void *buffer, size_t size,
1364                           void *answer, size_t asize, size_t *residual)
1365 {
1366         union iucv_param *parm;
1367         int rc;
1368
1369         local_bh_disable();
1370         if (cpumask_empty(&iucv_buffer_cpumask)) {
1371                 rc = -EIO;
1372                 goto out;
1373         }
1374         parm = iucv_param[smp_processor_id()];
1375         memset(parm, 0, sizeof(union iucv_param));
1376         if (flags & IUCV_IPRMDATA) {
1377                 parm->dpl.ippathid = path->pathid;
1378                 parm->dpl.ipflags1 = path->flags;       /* priority message */
1379                 parm->dpl.iptrgcls = msg->class;
1380                 parm->dpl.ipsrccls = srccls;
1381                 parm->dpl.ipmsgtag = msg->tag;
1382                 parm->dpl.ipbfadr2 = (u32)virt_to_phys(answer);
1383                 parm->dpl.ipbfln2f = (u32) asize;
1384                 memcpy(parm->dpl.iprmmsg, buffer, 8);
1385         } else {
1386                 parm->db.ippathid = path->pathid;
1387                 parm->db.ipflags1 = path->flags;        /* priority message */
1388                 parm->db.iptrgcls = msg->class;
1389                 parm->db.ipsrccls = srccls;
1390                 parm->db.ipmsgtag = msg->tag;
1391                 parm->db.ipbfadr1 = (u32)virt_to_phys(buffer);
1392                 parm->db.ipbfln1f = (u32) size;
1393                 parm->db.ipbfadr2 = (u32)virt_to_phys(answer);
1394                 parm->db.ipbfln2f = (u32) asize;
1395         }
1396         rc = iucv_call_b2f0(IUCV_SEND, parm);
1397         if (!rc)
1398                 msg->id = parm->db.ipmsgid;
1399 out:
1400         local_bh_enable();
1401         return rc;
1402 }
1403 EXPORT_SYMBOL(iucv_message_send2way);
1404
1405 struct iucv_path_pending {
1406         u16 ippathid;
1407         u8  ipflags1;
1408         u8  iptype;
1409         u16 ipmsglim;
1410         u16 res1;
1411         u8  ipvmid[8];
1412         u8  ipuser[16];
1413         u32 res3;
1414         u8  ippollfg;
1415         u8  res4[3];
1416 } __packed;
1417
1418 /**
1419  * iucv_path_pending
1420  * @data: Pointer to external interrupt buffer
1421  *
1422  * Process connection pending work item. Called from tasklet while holding
1423  * iucv_table_lock.
1424  */
1425 static void iucv_path_pending(struct iucv_irq_data *data)
1426 {
1427         struct iucv_path_pending *ipp = (void *) data;
1428         struct iucv_handler *handler;
1429         struct iucv_path *path;
1430         char *error;
1431
1432         BUG_ON(iucv_path_table[ipp->ippathid]);
1433         /* New pathid, handler found. Create a new path struct. */
1434         error = iucv_error_no_memory;
1435         path = iucv_path_alloc(ipp->ipmsglim, ipp->ipflags1, GFP_ATOMIC);
1436         if (!path)
1437                 goto out_sever;
1438         path->pathid = ipp->ippathid;
1439         iucv_path_table[path->pathid] = path;
1440         EBCASC(ipp->ipvmid, 8);
1441
1442         /* Call registered handler until one is found that wants the path. */
1443         list_for_each_entry(handler, &iucv_handler_list, list) {
1444                 if (!handler->path_pending)
1445                         continue;
1446                 /*
1447                  * Add path to handler to allow a call to iucv_path_sever
1448                  * inside the path_pending function. If the handler returns
1449                  * an error remove the path from the handler again.
1450                  */
1451                 list_add(&path->list, &handler->paths);
1452                 path->handler = handler;
1453                 if (!handler->path_pending(path, ipp->ipvmid, ipp->ipuser))
1454                         return;
1455                 list_del(&path->list);
1456                 path->handler = NULL;
1457         }
1458         /* No handler wanted the path. */
1459         iucv_path_table[path->pathid] = NULL;
1460         iucv_path_free(path);
1461         error = iucv_error_no_listener;
1462 out_sever:
1463         iucv_sever_pathid(ipp->ippathid, error);
1464 }
1465
1466 struct iucv_path_complete {
1467         u16 ippathid;
1468         u8  ipflags1;
1469         u8  iptype;
1470         u16 ipmsglim;
1471         u16 res1;
1472         u8  res2[8];
1473         u8  ipuser[16];
1474         u32 res3;
1475         u8  ippollfg;
1476         u8  res4[3];
1477 } __packed;
1478
1479 /**
1480  * iucv_path_complete
1481  * @data: Pointer to external interrupt buffer
1482  *
1483  * Process connection complete work item. Called from tasklet while holding
1484  * iucv_table_lock.
1485  */
1486 static void iucv_path_complete(struct iucv_irq_data *data)
1487 {
1488         struct iucv_path_complete *ipc = (void *) data;
1489         struct iucv_path *path = iucv_path_table[ipc->ippathid];
1490
1491         if (path)
1492                 path->flags = ipc->ipflags1;
1493         if (path && path->handler && path->handler->path_complete)
1494                 path->handler->path_complete(path, ipc->ipuser);
1495 }
1496
1497 struct iucv_path_severed {
1498         u16 ippathid;
1499         u8  res1;
1500         u8  iptype;
1501         u32 res2;
1502         u8  res3[8];
1503         u8  ipuser[16];
1504         u32 res4;
1505         u8  ippollfg;
1506         u8  res5[3];
1507 } __packed;
1508
1509 /**
1510  * iucv_path_severed
1511  * @data: Pointer to external interrupt buffer
1512  *
1513  * Process connection severed work item. Called from tasklet while holding
1514  * iucv_table_lock.
1515  */
1516 static void iucv_path_severed(struct iucv_irq_data *data)
1517 {
1518         struct iucv_path_severed *ips = (void *) data;
1519         struct iucv_path *path = iucv_path_table[ips->ippathid];
1520
1521         if (!path || !path->handler)    /* Already severed */
1522                 return;
1523         if (path->handler->path_severed)
1524                 path->handler->path_severed(path, ips->ipuser);
1525         else {
1526                 iucv_sever_pathid(path->pathid, NULL);
1527                 iucv_path_table[path->pathid] = NULL;
1528                 list_del(&path->list);
1529                 iucv_path_free(path);
1530         }
1531 }
1532
1533 struct iucv_path_quiesced {
1534         u16 ippathid;
1535         u8  res1;
1536         u8  iptype;
1537         u32 res2;
1538         u8  res3[8];
1539         u8  ipuser[16];
1540         u32 res4;
1541         u8  ippollfg;
1542         u8  res5[3];
1543 } __packed;
1544
1545 /**
1546  * iucv_path_quiesced
1547  * @data: Pointer to external interrupt buffer
1548  *
1549  * Process connection quiesced work item. Called from tasklet while holding
1550  * iucv_table_lock.
1551  */
1552 static void iucv_path_quiesced(struct iucv_irq_data *data)
1553 {
1554         struct iucv_path_quiesced *ipq = (void *) data;
1555         struct iucv_path *path = iucv_path_table[ipq->ippathid];
1556
1557         if (path && path->handler && path->handler->path_quiesced)
1558                 path->handler->path_quiesced(path, ipq->ipuser);
1559 }
1560
1561 struct iucv_path_resumed {
1562         u16 ippathid;
1563         u8  res1;
1564         u8  iptype;
1565         u32 res2;
1566         u8  res3[8];
1567         u8  ipuser[16];
1568         u32 res4;
1569         u8  ippollfg;
1570         u8  res5[3];
1571 } __packed;
1572
1573 /**
1574  * iucv_path_resumed
1575  * @data: Pointer to external interrupt buffer
1576  *
1577  * Process connection resumed work item. Called from tasklet while holding
1578  * iucv_table_lock.
1579  */
1580 static void iucv_path_resumed(struct iucv_irq_data *data)
1581 {
1582         struct iucv_path_resumed *ipr = (void *) data;
1583         struct iucv_path *path = iucv_path_table[ipr->ippathid];
1584
1585         if (path && path->handler && path->handler->path_resumed)
1586                 path->handler->path_resumed(path, ipr->ipuser);
1587 }
1588
1589 struct iucv_message_complete {
1590         u16 ippathid;
1591         u8  ipflags1;
1592         u8  iptype;
1593         u32 ipmsgid;
1594         u32 ipaudit;
1595         u8  iprmmsg[8];
1596         u32 ipsrccls;
1597         u32 ipmsgtag;
1598         u32 res;
1599         u32 ipbfln2f;
1600         u8  ippollfg;
1601         u8  res2[3];
1602 } __packed;
1603
1604 /**
1605  * iucv_message_complete
1606  * @data: Pointer to external interrupt buffer
1607  *
1608  * Process message complete work item. Called from tasklet while holding
1609  * iucv_table_lock.
1610  */
1611 static void iucv_message_complete(struct iucv_irq_data *data)
1612 {
1613         struct iucv_message_complete *imc = (void *) data;
1614         struct iucv_path *path = iucv_path_table[imc->ippathid];
1615         struct iucv_message msg;
1616
1617         if (path && path->handler && path->handler->message_complete) {
1618                 msg.flags = imc->ipflags1;
1619                 msg.id = imc->ipmsgid;
1620                 msg.audit = imc->ipaudit;
1621                 memcpy(msg.rmmsg, imc->iprmmsg, 8);
1622                 msg.class = imc->ipsrccls;
1623                 msg.tag = imc->ipmsgtag;
1624                 msg.length = imc->ipbfln2f;
1625                 path->handler->message_complete(path, &msg);
1626         }
1627 }
1628
1629 struct iucv_message_pending {
1630         u16 ippathid;
1631         u8  ipflags1;
1632         u8  iptype;
1633         u32 ipmsgid;
1634         u32 iptrgcls;
1635         struct {
1636                 union {
1637                         u32 iprmmsg1_u32;
1638                         u8  iprmmsg1[4];
1639                 } ln1msg1;
1640                 union {
1641                         u32 ipbfln1f;
1642                         u8  iprmmsg2[4];
1643                 } ln1msg2;
1644         } rmmsg;
1645         u32 res1[3];
1646         u32 ipbfln2f;
1647         u8  ippollfg;
1648         u8  res2[3];
1649 } __packed;
1650
1651 /**
1652  * iucv_message_pending
1653  * @data: Pointer to external interrupt buffer
1654  *
1655  * Process message pending work item. Called from tasklet while holding
1656  * iucv_table_lock.
1657  */
1658 static void iucv_message_pending(struct iucv_irq_data *data)
1659 {
1660         struct iucv_message_pending *imp = (void *) data;
1661         struct iucv_path *path = iucv_path_table[imp->ippathid];
1662         struct iucv_message msg;
1663
1664         if (path && path->handler && path->handler->message_pending) {
1665                 msg.flags = imp->ipflags1;
1666                 msg.id = imp->ipmsgid;
1667                 msg.class = imp->iptrgcls;
1668                 if (imp->ipflags1 & IUCV_IPRMDATA) {
1669                         memcpy(msg.rmmsg, &imp->rmmsg, 8);
1670                         msg.length = 8;
1671                 } else
1672                         msg.length = imp->rmmsg.ln1msg2.ipbfln1f;
1673                 msg.reply_size = imp->ipbfln2f;
1674                 path->handler->message_pending(path, &msg);
1675         }
1676 }
1677
1678 /*
1679  * iucv_tasklet_fn:
1680  *
1681  * This tasklet loops over the queue of irq buffers created by
1682  * iucv_external_interrupt, calls the appropriate action handler
1683  * and then frees the buffer.
1684  */
1685 static void iucv_tasklet_fn(unsigned long ignored)
1686 {
1687         typedef void iucv_irq_fn(struct iucv_irq_data *);
1688         static iucv_irq_fn *irq_fn[] = {
1689                 [0x02] = iucv_path_complete,
1690                 [0x03] = iucv_path_severed,
1691                 [0x04] = iucv_path_quiesced,
1692                 [0x05] = iucv_path_resumed,
1693                 [0x06] = iucv_message_complete,
1694                 [0x07] = iucv_message_complete,
1695                 [0x08] = iucv_message_pending,
1696                 [0x09] = iucv_message_pending,
1697         };
1698         LIST_HEAD(task_queue);
1699         struct iucv_irq_list *p, *n;
1700
1701         /* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1702         if (!spin_trylock(&iucv_table_lock)) {
1703                 tasklet_schedule(&iucv_tasklet);
1704                 return;
1705         }
1706         iucv_active_cpu = smp_processor_id();
1707
1708         spin_lock_irq(&iucv_queue_lock);
1709         list_splice_init(&iucv_task_queue, &task_queue);
1710         spin_unlock_irq(&iucv_queue_lock);
1711
1712         list_for_each_entry_safe(p, n, &task_queue, list) {
1713                 list_del_init(&p->list);
1714                 irq_fn[p->data.iptype](&p->data);
1715                 kfree(p);
1716         }
1717
1718         iucv_active_cpu = -1;
1719         spin_unlock(&iucv_table_lock);
1720 }
1721
1722 /*
1723  * iucv_work_fn:
1724  *
1725  * This work function loops over the queue of path pending irq blocks
1726  * created by iucv_external_interrupt, calls the appropriate action
1727  * handler and then frees the buffer.
1728  */
1729 static void iucv_work_fn(struct work_struct *work)
1730 {
1731         LIST_HEAD(work_queue);
1732         struct iucv_irq_list *p, *n;
1733
1734         /* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1735         spin_lock_bh(&iucv_table_lock);
1736         iucv_active_cpu = smp_processor_id();
1737
1738         spin_lock_irq(&iucv_queue_lock);
1739         list_splice_init(&iucv_work_queue, &work_queue);
1740         spin_unlock_irq(&iucv_queue_lock);
1741
1742         iucv_cleanup_queue();
1743         list_for_each_entry_safe(p, n, &work_queue, list) {
1744                 list_del_init(&p->list);
1745                 iucv_path_pending(&p->data);
1746                 kfree(p);
1747         }
1748
1749         iucv_active_cpu = -1;
1750         spin_unlock_bh(&iucv_table_lock);
1751 }
1752
1753 /*
1754  * iucv_external_interrupt
1755  *
1756  * Handles external interrupts coming in from CP.
1757  * Places the interrupt buffer on a queue and schedules iucv_tasklet_fn().
1758  */
1759 static void iucv_external_interrupt(struct ext_code ext_code,
1760                                     unsigned int param32, unsigned long param64)
1761 {
1762         struct iucv_irq_data *p;
1763         struct iucv_irq_list *work;
1764
1765         inc_irq_stat(IRQEXT_IUC);
1766         p = iucv_irq_data[smp_processor_id()];
1767         if (p->ippathid >= iucv_max_pathid) {
1768                 WARN_ON(p->ippathid >= iucv_max_pathid);
1769                 iucv_sever_pathid(p->ippathid, iucv_error_no_listener);
1770                 return;
1771         }
1772         BUG_ON(p->iptype  < 0x01 || p->iptype > 0x09);
1773         work = kmalloc(sizeof(struct iucv_irq_list), GFP_ATOMIC);
1774         if (!work) {
1775                 pr_warn("iucv_external_interrupt: out of memory\n");
1776                 return;
1777         }
1778         memcpy(&work->data, p, sizeof(work->data));
1779         spin_lock(&iucv_queue_lock);
1780         if (p->iptype == 0x01) {
1781                 /* Path pending interrupt. */
1782                 list_add_tail(&work->list, &iucv_work_queue);
1783                 schedule_work(&iucv_work);
1784         } else {
1785                 /* The other interrupts. */
1786                 list_add_tail(&work->list, &iucv_task_queue);
1787                 tasklet_schedule(&iucv_tasklet);
1788         }
1789         spin_unlock(&iucv_queue_lock);
1790 }
1791
1792 struct iucv_interface iucv_if = {
1793         .message_receive = iucv_message_receive,
1794         .__message_receive = __iucv_message_receive,
1795         .message_reply = iucv_message_reply,
1796         .message_reject = iucv_message_reject,
1797         .message_send = iucv_message_send,
1798         .__message_send = __iucv_message_send,
1799         .message_send2way = iucv_message_send2way,
1800         .message_purge = iucv_message_purge,
1801         .path_accept = iucv_path_accept,
1802         .path_connect = iucv_path_connect,
1803         .path_quiesce = iucv_path_quiesce,
1804         .path_resume = iucv_path_resume,
1805         .path_sever = iucv_path_sever,
1806         .iucv_register = iucv_register,
1807         .iucv_unregister = iucv_unregister,
1808         .bus = NULL,
1809         .root = NULL,
1810 };
1811 EXPORT_SYMBOL(iucv_if);
1812
1813 static enum cpuhp_state iucv_online;
1814 /**
1815  * iucv_init
1816  *
1817  * Allocates and initializes various data structures.
1818  */
1819 static int __init iucv_init(void)
1820 {
1821         int rc;
1822
1823         if (!MACHINE_IS_VM) {
1824                 rc = -EPROTONOSUPPORT;
1825                 goto out;
1826         }
1827         system_ctl_set_bit(0, CR0_IUCV_BIT);
1828         rc = iucv_query_maxconn();
1829         if (rc)
1830                 goto out_ctl;
1831         rc = register_external_irq(EXT_IRQ_IUCV, iucv_external_interrupt);
1832         if (rc)
1833                 goto out_ctl;
1834         iucv_root = root_device_register("iucv");
1835         if (IS_ERR(iucv_root)) {
1836                 rc = PTR_ERR(iucv_root);
1837                 goto out_int;
1838         }
1839
1840         rc = cpuhp_setup_state(CPUHP_NET_IUCV_PREPARE, "net/iucv:prepare",
1841                                iucv_cpu_prepare, iucv_cpu_dead);
1842         if (rc)
1843                 goto out_dev;
1844         rc = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "net/iucv:online",
1845                                iucv_cpu_online, iucv_cpu_down_prep);
1846         if (rc < 0)
1847                 goto out_prep;
1848         iucv_online = rc;
1849
1850         rc = register_reboot_notifier(&iucv_reboot_notifier);
1851         if (rc)
1852                 goto out_remove_hp;
1853         ASCEBC(iucv_error_no_listener, 16);
1854         ASCEBC(iucv_error_no_memory, 16);
1855         ASCEBC(iucv_error_pathid, 16);
1856         iucv_available = 1;
1857         rc = bus_register(&iucv_bus);
1858         if (rc)
1859                 goto out_reboot;
1860         iucv_if.root = iucv_root;
1861         iucv_if.bus = &iucv_bus;
1862         return 0;
1863
1864 out_reboot:
1865         unregister_reboot_notifier(&iucv_reboot_notifier);
1866 out_remove_hp:
1867         cpuhp_remove_state(iucv_online);
1868 out_prep:
1869         cpuhp_remove_state(CPUHP_NET_IUCV_PREPARE);
1870 out_dev:
1871         root_device_unregister(iucv_root);
1872 out_int:
1873         unregister_external_irq(EXT_IRQ_IUCV, iucv_external_interrupt);
1874 out_ctl:
1875         system_ctl_clear_bit(0, 1);
1876 out:
1877         return rc;
1878 }
1879
1880 /**
1881  * iucv_exit
1882  *
1883  * Frees everything allocated from iucv_init.
1884  */
1885 static void __exit iucv_exit(void)
1886 {
1887         struct iucv_irq_list *p, *n;
1888
1889         spin_lock_irq(&iucv_queue_lock);
1890         list_for_each_entry_safe(p, n, &iucv_task_queue, list)
1891                 kfree(p);
1892         list_for_each_entry_safe(p, n, &iucv_work_queue, list)
1893                 kfree(p);
1894         spin_unlock_irq(&iucv_queue_lock);
1895         unregister_reboot_notifier(&iucv_reboot_notifier);
1896
1897         cpuhp_remove_state_nocalls(iucv_online);
1898         cpuhp_remove_state(CPUHP_NET_IUCV_PREPARE);
1899         root_device_unregister(iucv_root);
1900         bus_unregister(&iucv_bus);
1901         unregister_external_irq(EXT_IRQ_IUCV, iucv_external_interrupt);
1902 }
1903
1904 subsys_initcall(iucv_init);
1905 module_exit(iucv_exit);
1906
1907 MODULE_AUTHOR("(C) 2001 IBM Corp. by Fritz Elfert <felfert@millenux.com>");
1908 MODULE_DESCRIPTION("Linux for S/390 IUCV lowlevel driver");
1909 MODULE_LICENSE("GPL");