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 ([email protected])  Sept. 2000
  10  *      Xenia Tkatschow ([email protected])
  11  *    2Gb awareness and general cleanup:
  12  *      Fritz Elfert ([email protected], [email protected])
  13  *    Rewritten for af_iucv:
  14  *      Martin Schwidefsky <[email protected]>
  15  *    PM functions:
  16  *      Ursula Braun ([email protected])
  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 static struct device *iucv_root;
  77
  78 static void iucv_release_device(struct device *device)
  79 {
  80         kfree(device);
  81 }
  82
  83 struct device *iucv_alloc_device(const struct attribute_group **attrs,
  84                                  struct device_driver *driver,
  85                                  void *priv, const char *fmt, ...)
  86 {
  87         struct device *dev;
  88         va_list vargs;
  89         int rc;
  90
  91         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
  92         if (!dev)
  93                 goto out_error;
  94         va_start(vargs, fmt);
  95         rc = dev_set_name(dev, fmt, vargs);
  96         va_end(vargs);
  97         if (rc)
  98                 goto out_error;
  99         dev->bus = &iucv_bus;
 100         dev->parent = iucv_root;
 101         dev->driver = driver;
 102         dev->groups = attrs;
 103         dev->release = iucv_release_device;
 104         dev_set_drvdata(dev, priv);
 105         return dev;
 106
 107 out_error:
 108         kfree(dev);
 109         return NULL;
 110 }
 111 EXPORT_SYMBOL(iucv_alloc_device);
 112
 113 static int iucv_available;
 114
 115 /* General IUCV interrupt structure */
 116 struct iucv_irq_data {
 117         u16 ippathid;
 118         u8  ipflags1;
 119         u8  iptype;
 120         u32 res2[9];
 121 };
 122
 123 struct iucv_irq_list {
 124         struct list_head list;
 125         struct iucv_irq_data data;
 126 };
 127
 128 static struct iucv_irq_data *iucv_irq_data[NR_CPUS];
 129 static cpumask_t iucv_buffer_cpumask = { CPU_BITS_NONE };
 130 static cpumask_t iucv_irq_cpumask = { CPU_BITS_NONE };
 131
 132 /*
 133  * Queue of interrupt buffers lock for delivery via the tasklet
 134  * (fast but can't call smp_call_function).
 135  */
 136 static LIST_HEAD(iucv_task_queue);
 137
 138 /*
 139  * The tasklet for fast delivery of iucv interrupts.
 140  */
 141 static void iucv_tasklet_fn(unsigned long);
 142 static DECLARE_TASKLET_OLD(iucv_tasklet, iucv_tasklet_fn);
 143
 144 /*
 145  * Queue of interrupt buffers for delivery via a work queue
 146  * (slower but can call smp_call_function).
 147  */
 148 static LIST_HEAD(iucv_work_queue);
 149
 150 /*
 151  * The work element to deliver path pending interrupts.
 152  */
 153 static void iucv_work_fn(struct work_struct *work);
 154 static DECLARE_WORK(iucv_work, iucv_work_fn);
 155
 156 /*
 157  * Spinlock protecting task and work queue.
 158  */
 159 static DEFINE_SPINLOCK(iucv_queue_lock);
 160
 161 enum iucv_command_codes {
 162         IUCV_QUERY = 0,
 163         IUCV_RETRIEVE_BUFFER = 2,
 164         IUCV_SEND = 4,
 165         IUCV_RECEIVE = 5,
 166         IUCV_REPLY = 6,
 167         IUCV_REJECT = 8,
 168         IUCV_PURGE = 9,
 169         IUCV_ACCEPT = 10,
 170         IUCV_CONNECT = 11,
 171         IUCV_DECLARE_BUFFER = 12,
 172         IUCV_QUIESCE = 13,
 173         IUCV_RESUME = 14,
 174         IUCV_SEVER = 15,
 175         IUCV_SETMASK = 16,
 176         IUCV_SETCONTROLMASK = 17,
 177 };
 178
 179 /*
 180  * Error messages that are used with the iucv_sever function. They get
 181  * converted to EBCDIC.
 182  */
 183 static char iucv_error_no_listener[16] = "NO LISTENER";
 184 static char iucv_error_no_memory[16] = "NO MEMORY";
 185 static char iucv_error_pathid[16] = "INVALID PATHID";
 186
 187 /*
 188  * iucv_handler_list: List of registered handlers.
 189  */
 190 static LIST_HEAD(iucv_handler_list);
 191
 192 /*
 193  * iucv_path_table: array of pointers to iucv_path structures.
 194  */
 195 static struct iucv_path **iucv_path_table;
 196 static unsigned long iucv_max_pathid;
 197
 198 /*
 199  * iucv_lock: spinlock protecting iucv_handler_list and iucv_pathid_table
 200  */
 201 static DEFINE_SPINLOCK(iucv_table_lock);
 202
 203 /*
 204  * iucv_active_cpu: contains the number of the cpu executing the tasklet
 205  * or the work handler. Needed for iucv_path_sever called from tasklet.
 206  */
 207 static int iucv_active_cpu = -1;
 208
 209 /*
 210  * Mutex and wait queue for iucv_register/iucv_unregister.
 211  */
 212 static DEFINE_MUTEX(iucv_register_mutex);
 213
 214 /*
 215  * Counter for number of non-smp capable handlers.
 216  */
 217 static int iucv_nonsmp_handler;
 218
 219 /*
 220  * IUCV control data structure. Used by iucv_path_accept, iucv_path_connect,
 221  * iucv_path_quiesce and iucv_path_sever.
 222  */
 223 struct iucv_cmd_control {
 224         u16 ippathid;
 225         u8  ipflags1;
 226         u8  iprcode;
 227         u16 ipmsglim;
 228         u16 res1;
 229         u8  ipvmid[8];
 230         u8  ipuser[16];
 231         u8  iptarget[8];
 232 } __attribute__ ((packed,aligned(8)));
 233
 234 /*
 235  * Data in parameter list iucv structure. Used by iucv_message_send,
 236  * iucv_message_send2way and iucv_message_reply.
 237  */
 238 struct iucv_cmd_dpl {
 239         u16 ippathid;
 240         u8  ipflags1;
 241         u8  iprcode;
 242         u32 ipmsgid;
 243         u32 iptrgcls;
 244         u8  iprmmsg[8];
 245         u32 ipsrccls;
 246         u32 ipmsgtag;
 247         dma32_t ipbfadr2;
 248         u32 ipbfln2f;
 249         u32 res;
 250 } __attribute__ ((packed,aligned(8)));
 251
 252 /*
 253  * Data in buffer iucv structure. Used by iucv_message_receive,
 254  * iucv_message_reject, iucv_message_send, iucv_message_send2way
 255  * and iucv_declare_cpu.
 256  */
 257 struct iucv_cmd_db {
 258         u16 ippathid;
 259         u8  ipflags1;
 260         u8  iprcode;
 261         u32 ipmsgid;
 262         u32 iptrgcls;
 263         dma32_t ipbfadr1;
 264         u32 ipbfln1f;
 265         u32 ipsrccls;
 266         u32 ipmsgtag;
 267         dma32_t ipbfadr2;
 268         u32 ipbfln2f;
 269         u32 res;
 270 } __attribute__ ((packed,aligned(8)));
 271
 272 /*
 273  * Purge message iucv structure. Used by iucv_message_purge.
 274  */
 275 struct iucv_cmd_purge {
 276         u16 ippathid;
 277         u8  ipflags1;
 278         u8  iprcode;
 279         u32 ipmsgid;
 280         u8  ipaudit[3];
 281         u8  res1[5];
 282         u32 res2;
 283         u32 ipsrccls;
 284         u32 ipmsgtag;
 285         u32 res3[3];
 286 } __attribute__ ((packed,aligned(8)));
 287
 288 /*
 289  * Set mask iucv structure. Used by iucv_enable_cpu.
 290  */
 291 struct iucv_cmd_set_mask {
 292         u8  ipmask;
 293         u8  res1[2];
 294         u8  iprcode;
 295         u32 res2[9];
 296 } __attribute__ ((packed,aligned(8)));
 297
 298 union iucv_param {
 299         struct iucv_cmd_control ctrl;
 300         struct iucv_cmd_dpl dpl;
 301         struct iucv_cmd_db db;
 302         struct iucv_cmd_purge purge;
 303         struct iucv_cmd_set_mask set_mask;
 304 };
 305
 306 /*
 307  * Anchor for per-cpu IUCV command parameter block.
 308  */
 309 static union iucv_param *iucv_param[NR_CPUS];
 310 static union iucv_param *iucv_param_irq[NR_CPUS];
 311
 312 /**
 313  * __iucv_call_b2f0
 314  * @command: identifier of IUCV call to CP.
 315  * @parm: pointer to a struct iucv_parm block
 316  *
 317  * Calls CP to execute IUCV commands.
 318  *
 319  * Returns the result of the CP IUCV call.
 320  */
 321 static inline int __iucv_call_b2f0(int command, union iucv_param *parm)
 322 {
 323         unsigned long reg1 = virt_to_phys(parm);
 324         int cc;
 325
 326         asm volatile(
 327                 "       lgr     0,%[reg0]\n"
 328                 "       lgr     1,%[reg1]\n"
 329                 "       .long   0xb2f01000\n"
 330                 "       ipm     %[cc]\n"
 331                 "       srl     %[cc],28\n"
 332                 : [cc] "=&d" (cc), "+m" (*parm)
 333                 : [reg0] "d" ((unsigned long)command),
 334                   [reg1] "d" (reg1)
 335                 : "cc", "0", "1");
 336         return cc;
 337 }
 338
 339 static inline int iucv_call_b2f0(int command, union iucv_param *parm)
 340 {
 341         int ccode;
 342
 343         ccode = __iucv_call_b2f0(command, parm);
 344         return ccode == 1 ? parm->ctrl.iprcode : ccode;
 345 }
 346
 347 /*
 348  * iucv_query_maxconn
 349  *
 350  * Determines the maximum number of connections that may be established.
 351  *
 352  * Returns the maximum number of connections or -EPERM is IUCV is not
 353  * available.
 354  */
 355 static int __iucv_query_maxconn(void *param, unsigned long *max_pathid)
 356 {
 357         unsigned long reg1 = virt_to_phys(param);
 358         int cc;
 359
 360         asm volatile (
 361                 "       lghi    0,%[cmd]\n"
 362                 "       lgr     1,%[reg1]\n"
 363                 "       .long   0xb2f01000\n"
 364                 "       ipm     %[cc]\n"
 365                 "       srl     %[cc],28\n"
 366                 "       lgr     %[reg1],1\n"
 367                 : [cc] "=&d" (cc), [reg1] "+&d" (reg1)
 368                 : [cmd] "K" (IUCV_QUERY)
 369                 : "cc", "0", "1");
 370         *max_pathid = reg1;
 371         return cc;
 372 }
 373
 374 static int iucv_query_maxconn(void)
 375 {
 376         unsigned long max_pathid;
 377         void *param;
 378         int ccode;
 379
 380         param = kzalloc(sizeof(union iucv_param), GFP_KERNEL | GFP_DMA);
 381         if (!param)
 382                 return -ENOMEM;
 383         ccode = __iucv_query_maxconn(param, &max_pathid);
 384         if (ccode == 0)
 385                 iucv_max_pathid = max_pathid;
 386         kfree(param);
 387         return ccode ? -EPERM : 0;
 388 }
 389
 390 /**
 391  * iucv_allow_cpu
 392  * @data: unused
 393  *
 394  * Allow iucv interrupts on this cpu.
 395  */
 396 static void iucv_allow_cpu(void *data)
 397 {
 398         int cpu = smp_processor_id();
 399         union iucv_param *parm;
 400
 401         /*
 402          * Enable all iucv interrupts.
 403          * ipmask contains bits for the different interrupts
 404          *      0x80 - Flag to allow nonpriority message pending interrupts
 405          *      0x40 - Flag to allow priority message pending interrupts
 406          *      0x20 - Flag to allow nonpriority message completion interrupts
 407          *      0x10 - Flag to allow priority message completion interrupts
 408          *      0x08 - Flag to allow IUCV control interrupts
 409          */
 410         parm = iucv_param_irq[cpu];
 411         memset(parm, 0, sizeof(union iucv_param));
 412         parm->set_mask.ipmask = 0xf8;
 413         iucv_call_b2f0(IUCV_SETMASK, parm);
 414
 415         /*
 416          * Enable all iucv control interrupts.
 417          * ipmask contains bits for the different interrupts
 418          *      0x80 - Flag to allow pending connections interrupts
 419          *      0x40 - Flag to allow connection complete interrupts
 420          *      0x20 - Flag to allow connection severed interrupts
 421          *      0x10 - Flag to allow connection quiesced interrupts
 422          *      0x08 - Flag to allow connection resumed interrupts
 423          */
 424         memset(parm, 0, sizeof(union iucv_param));
 425         parm->set_mask.ipmask = 0xf8;
 426         iucv_call_b2f0(IUCV_SETCONTROLMASK, parm);
 427         /* Set indication that iucv interrupts are allowed for this cpu. */
 428         cpumask_set_cpu(cpu, &iucv_irq_cpumask);
 429 }
 430
 431 /**
 432  * iucv_block_cpu
 433  * @data: unused
 434  *
 435  * Block iucv interrupts on this cpu.
 436  */
 437 static void iucv_block_cpu(void *data)
 438 {
 439         int cpu = smp_processor_id();
 440         union iucv_param *parm;
 441
 442         /* Disable all iucv interrupts. */
 443         parm = iucv_param_irq[cpu];
 444         memset(parm, 0, sizeof(union iucv_param));
 445         iucv_call_b2f0(IUCV_SETMASK, parm);
 446
 447         /* Clear indication that iucv interrupts are allowed for this cpu. */
 448         cpumask_clear_cpu(cpu, &iucv_irq_cpumask);
 449 }
 450
 451 /**
 452  * iucv_declare_cpu
 453  * @data: unused
 454  *
 455  * Declare a interrupt buffer on this cpu.
 456  */
 457 static void iucv_declare_cpu(void *data)
 458 {
 459         int cpu = smp_processor_id();
 460         union iucv_param *parm;
 461         int rc;
 462
 463         if (cpumask_test_cpu(cpu, &iucv_buffer_cpumask))
 464                 return;
 465
 466         /* Declare interrupt buffer. */
 467         parm = iucv_param_irq[cpu];
 468         memset(parm, 0, sizeof(union iucv_param));
 469         parm->db.ipbfadr1 = virt_to_dma32(iucv_irq_data[cpu]);
 470         rc = iucv_call_b2f0(IUCV_DECLARE_BUFFER, parm);
 471         if (rc) {
 472                 char *err = "Unknown";
 473                 switch (rc) {
 474                 case 0x03:
 475                         err = "Directory error";
 476                         break;
 477                 case 0x0a:
 478                         err = "Invalid length";
 479                         break;
 480                 case 0x13:
 481                         err = "Buffer already exists";
 482                         break;
 483                 case 0x3e:
 484                         err = "Buffer overlap";
 485                         break;
 486                 case 0x5c:
 487                         err = "Paging or storage error";
 488                         break;
 489                 }
 490                 pr_warn("Defining an interrupt buffer on CPU %i failed with 0x%02x (%s)\n",
 491                         cpu, rc, err);
 492                 return;
 493         }
 494
 495         /* Set indication that an iucv buffer exists for this cpu. */
 496         cpumask_set_cpu(cpu, &iucv_buffer_cpumask);
 497
 498         if (iucv_nonsmp_handler == 0 || cpumask_empty(&iucv_irq_cpumask))
 499                 /* Enable iucv interrupts on this cpu. */
 500                 iucv_allow_cpu(NULL);
 501         else
 502                 /* Disable iucv interrupts on this cpu. */
 503                 iucv_block_cpu(NULL);
 504 }
 505
 506 /**
 507  * iucv_retrieve_cpu
 508  * @data: unused
 509  *
 510  * Retrieve interrupt buffer on this cpu.
 511  */
 512 static void iucv_retrieve_cpu(void *data)
 513 {
 514         int cpu = smp_processor_id();
 515         union iucv_param *parm;
 516
 517         if (!cpumask_test_cpu(cpu, &iucv_buffer_cpumask))
 518                 return;
 519
 520         /* Block iucv interrupts. */
 521         iucv_block_cpu(NULL);
 522
 523         /* Retrieve interrupt buffer. */
 524         parm = iucv_param_irq[cpu];
 525         iucv_call_b2f0(IUCV_RETRIEVE_BUFFER, parm);
 526
 527         /* Clear indication that an iucv buffer exists for this cpu. */
 528         cpumask_clear_cpu(cpu, &iucv_buffer_cpumask);
 529 }
 530
 531 /*
 532  * iucv_setmask_mp
 533  *
 534  * Allow iucv interrupts on all cpus.
 535  */
 536 static void iucv_setmask_mp(void)
 537 {
 538         int cpu;
 539
 540         cpus_read_lock();
 541         for_each_online_cpu(cpu)
 542                 /* Enable all cpus with a declared buffer. */
 543                 if (cpumask_test_cpu(cpu, &iucv_buffer_cpumask) &&
 544                     !cpumask_test_cpu(cpu, &iucv_irq_cpumask))
 545                         smp_call_function_single(cpu, iucv_allow_cpu,
 546                                                  NULL, 1);
 547         cpus_read_unlock();
 548 }
 549
 550 /*
 551  * iucv_setmask_up
 552  *
 553  * Allow iucv interrupts on a single cpu.
 554  */
 555 static void iucv_setmask_up(void)
 556 {
 557         static cpumask_t cpumask;
 558         int cpu;
 559
 560         /* Disable all cpu but the first in cpu_irq_cpumask. */
 561         cpumask_copy(&cpumask, &iucv_irq_cpumask);
 562         cpumask_clear_cpu(cpumask_first(&iucv_irq_cpumask), &cpumask);
 563         for_each_cpu(cpu, &cpumask)
 564                 smp_call_function_single(cpu, iucv_block_cpu, NULL, 1);
 565 }
 566
 567 /*
 568  * iucv_enable
 569  *
 570  * This function makes iucv ready for use. It allocates the pathid
 571  * table, declares an iucv interrupt buffer and enables the iucv
 572  * interrupts. Called when the first user has registered an iucv
 573  * handler.
 574  */
 575 static int iucv_enable(void)
 576 {
 577         size_t alloc_size;
 578         int cpu, rc;
 579
 580         cpus_read_lock();
 581         rc = -ENOMEM;
 582         alloc_size = iucv_max_pathid * sizeof(*iucv_path_table);
 583         iucv_path_table = kzalloc(alloc_size, GFP_KERNEL);
 584         if (!iucv_path_table)
 585                 goto out;
 586         /* Declare per cpu buffers. */
 587         rc = -EIO;
 588         for_each_online_cpu(cpu)
 589                 smp_call_function_single(cpu, iucv_declare_cpu, NULL, 1);
 590         if (cpumask_empty(&iucv_buffer_cpumask))
 591                 /* No cpu could declare an iucv buffer. */
 592                 goto out;
 593         cpus_read_unlock();
 594         return 0;
 595 out:
 596         kfree(iucv_path_table);
 597         iucv_path_table = NULL;
 598         cpus_read_unlock();
 599         return rc;
 600 }
 601
 602 /*
 603  * iucv_disable
 604  *
 605  * This function shuts down iucv. It disables iucv interrupts, retrieves
 606  * the iucv interrupt buffer and frees the pathid table. Called after the
 607  * last user unregister its iucv handler.
 608  */
 609 static void iucv_disable(void)
 610 {
 611         cpus_read_lock();
 612         on_each_cpu(iucv_retrieve_cpu, NULL, 1);
 613         kfree(iucv_path_table);
 614         iucv_path_table = NULL;
 615         cpus_read_unlock();
 616 }
 617
 618 static int iucv_cpu_dead(unsigned int cpu)
 619 {
 620         kfree(iucv_param_irq[cpu]);
 621         iucv_param_irq[cpu] = NULL;
 622         kfree(iucv_param[cpu]);
 623         iucv_param[cpu] = NULL;
 624         kfree(iucv_irq_data[cpu]);
 625         iucv_irq_data[cpu] = NULL;
 626         return 0;
 627 }
 628
 629 static int iucv_cpu_prepare(unsigned int cpu)
 630 {
 631         /* Note: GFP_DMA used to get memory below 2G */
 632         iucv_irq_data[cpu] = kmalloc_node(sizeof(struct iucv_irq_data),
 633                              GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
 634         if (!iucv_irq_data[cpu])
 635                 goto out_free;
 636
 637         /* Allocate parameter blocks. */
 638         iucv_param[cpu] = kmalloc_node(sizeof(union iucv_param),
 639                           GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
 640         if (!iucv_param[cpu])
 641                 goto out_free;
 642
 643         iucv_param_irq[cpu] = kmalloc_node(sizeof(union iucv_param),
 644                           GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
 645         if (!iucv_param_irq[cpu])
 646                 goto out_free;
 647
 648         return 0;
 649
 650 out_free:
 651         iucv_cpu_dead(cpu);
 652         return -ENOMEM;
 653 }
 654
 655 static int iucv_cpu_online(unsigned int cpu)
 656 {
 657         if (!iucv_path_table)
 658                 return 0;
 659         iucv_declare_cpu(NULL);
 660         return 0;
 661 }
 662
 663 static int iucv_cpu_down_prep(unsigned int cpu)
 664 {
 665         cpumask_var_t cpumask;
 666         int ret = 0;
 667
 668         if (!iucv_path_table)
 669                 return 0;
 670
 671         if (!alloc_cpumask_var(&cpumask, GFP_KERNEL))
 672                 return -ENOMEM;
 673
 674         cpumask_copy(cpumask, &iucv_buffer_cpumask);
 675         cpumask_clear_cpu(cpu, cpumask);
 676         if (cpumask_empty(cpumask)) {
 677                 /* Can't offline last IUCV enabled cpu. */
 678                 ret = -EINVAL;
 679                 goto __free_cpumask;
 680         }
 681
 682         iucv_retrieve_cpu(NULL);
 683         if (!cpumask_empty(&iucv_irq_cpumask))
 684                 goto __free_cpumask;
 685
 686         smp_call_function_single(cpumask_first(&iucv_buffer_cpumask),
 687                                  iucv_allow_cpu, NULL, 1);
 688
 689 __free_cpumask:
 690         free_cpumask_var(cpumask);
 691         return ret;
 692 }
 693
 694 /**
 695  * iucv_sever_pathid
 696  * @pathid: path identification number.
 697  * @userdata: 16-bytes of user data.
 698  *
 699  * Sever an iucv path to free up the pathid. Used internally.
 700  */
 701 static int iucv_sever_pathid(u16 pathid, u8 *userdata)
 702 {
 703         union iucv_param *parm;
 704
 705         parm = iucv_param_irq[smp_processor_id()];
 706         memset(parm, 0, sizeof(union iucv_param));
 707         if (userdata)
 708                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 709         parm->ctrl.ippathid = pathid;
 710         return iucv_call_b2f0(IUCV_SEVER, parm);
 711 }
 712
 713 /**
 714  * __iucv_cleanup_queue
 715  * @dummy: unused dummy argument
 716  *
 717  * Nop function called via smp_call_function to force work items from
 718  * pending external iucv interrupts to the work queue.
 719  */
 720 static void __iucv_cleanup_queue(void *dummy)
 721 {
 722 }
 723
 724 /**
 725  * iucv_cleanup_queue
 726  *
 727  * Function called after a path has been severed to find all remaining
 728  * work items for the now stale pathid. The caller needs to hold the
 729  * iucv_table_lock.
 730  */
 731 static void iucv_cleanup_queue(void)
 732 {
 733         struct iucv_irq_list *p, *n;
 734
 735         /*
 736          * When a path is severed, the pathid can be reused immediately
 737          * on a iucv connect or a connection pending interrupt. Remove
 738          * all entries from the task queue that refer to a stale pathid
 739          * (iucv_path_table[ix] == NULL). Only then do the iucv connect
 740          * or deliver the connection pending interrupt. To get all the
 741          * pending interrupts force them to the work queue by calling
 742          * an empty function on all cpus.
 743          */
 744         smp_call_function(__iucv_cleanup_queue, NULL, 1);
 745         spin_lock_irq(&iucv_queue_lock);
 746         list_for_each_entry_safe(p, n, &iucv_task_queue, list) {
 747                 /* Remove stale work items from the task queue. */
 748                 if (iucv_path_table[p->data.ippathid] == NULL) {
 749                         list_del(&p->list);
 750                         kfree(p);
 751                 }
 752         }
 753         spin_unlock_irq(&iucv_queue_lock);
 754 }
 755
 756 /**
 757  * iucv_register:
 758  * @handler: address of iucv handler structure
 759  * @smp: != 0 indicates that the handler can deal with out of order messages
 760  *
 761  * Registers a driver with IUCV.
 762  *
 763  * Returns 0 on success, -ENOMEM if the memory allocation for the pathid
 764  * table failed, or -EIO if IUCV_DECLARE_BUFFER failed on all cpus.
 765  */
 766 int iucv_register(struct iucv_handler *handler, int smp)
 767 {
 768         int rc;
 769
 770         if (!iucv_available)
 771                 return -ENOSYS;
 772         mutex_lock(&iucv_register_mutex);
 773         if (!smp)
 774                 iucv_nonsmp_handler++;
 775         if (list_empty(&iucv_handler_list)) {
 776                 rc = iucv_enable();
 777                 if (rc)
 778                         goto out_mutex;
 779         } else if (!smp && iucv_nonsmp_handler == 1)
 780                 iucv_setmask_up();
 781         INIT_LIST_HEAD(&handler->paths);
 782
 783         spin_lock_bh(&iucv_table_lock);
 784         list_add_tail(&handler->list, &iucv_handler_list);
 785         spin_unlock_bh(&iucv_table_lock);
 786         rc = 0;
 787 out_mutex:
 788         mutex_unlock(&iucv_register_mutex);
 789         return rc;
 790 }
 791 EXPORT_SYMBOL(iucv_register);
 792
 793 /**
 794  * iucv_unregister
 795  * @handler:  address of iucv handler structure
 796  * @smp: != 0 indicates that the handler can deal with out of order messages
 797  *
 798  * Unregister driver from IUCV.
 799  */
 800 void iucv_unregister(struct iucv_handler *handler, int smp)
 801 {
 802         struct iucv_path *p, *n;
 803
 804         mutex_lock(&iucv_register_mutex);
 805         spin_lock_bh(&iucv_table_lock);
 806         /* Remove handler from the iucv_handler_list. */
 807         list_del_init(&handler->list);
 808         /* Sever all pathids still referring to the handler. */
 809         list_for_each_entry_safe(p, n, &handler->paths, list) {
 810                 iucv_sever_pathid(p->pathid, NULL);
 811                 iucv_path_table[p->pathid] = NULL;
 812                 list_del(&p->list);
 813                 iucv_path_free(p);
 814         }
 815         spin_unlock_bh(&iucv_table_lock);
 816         if (!smp)
 817                 iucv_nonsmp_handler--;
 818         if (list_empty(&iucv_handler_list))
 819                 iucv_disable();
 820         else if (!smp && iucv_nonsmp_handler == 0)
 821                 iucv_setmask_mp();
 822         mutex_unlock(&iucv_register_mutex);
 823 }
 824 EXPORT_SYMBOL(iucv_unregister);
 825
 826 static int iucv_reboot_event(struct notifier_block *this,
 827                              unsigned long event, void *ptr)
 828 {
 829         int i;
 830
 831         if (cpumask_empty(&iucv_irq_cpumask))
 832                 return NOTIFY_DONE;
 833
 834         cpus_read_lock();
 835         on_each_cpu_mask(&iucv_irq_cpumask, iucv_block_cpu, NULL, 1);
 836         preempt_disable();
 837         for (i = 0; i < iucv_max_pathid; i++) {
 838                 if (iucv_path_table[i])
 839                         iucv_sever_pathid(i, NULL);
 840         }
 841         preempt_enable();
 842         cpus_read_unlock();
 843         iucv_disable();
 844         return NOTIFY_DONE;
 845 }
 846
 847 static struct notifier_block iucv_reboot_notifier = {
 848         .notifier_call = iucv_reboot_event,
 849 };
 850
 851 /**
 852  * iucv_path_accept
 853  * @path: address of iucv path structure
 854  * @handler: address of iucv handler structure
 855  * @userdata: 16 bytes of data reflected to the communication partner
 856  * @private: private data passed to interrupt handlers for this path
 857  *
 858  * This function is issued after the user received a connection pending
 859  * external interrupt and now wishes to complete the IUCV communication path.
 860  *
 861  * Returns the result of the CP IUCV call.
 862  */
 863 int iucv_path_accept(struct iucv_path *path, struct iucv_handler *handler,
 864                      u8 *userdata, void *private)
 865 {
 866         union iucv_param *parm;
 867         int rc;
 868
 869         local_bh_disable();
 870         if (cpumask_empty(&iucv_buffer_cpumask)) {
 871                 rc = -EIO;
 872                 goto out;
 873         }
 874         /* Prepare parameter block. */
 875         parm = iucv_param[smp_processor_id()];
 876         memset(parm, 0, sizeof(union iucv_param));
 877         parm->ctrl.ippathid = path->pathid;
 878         parm->ctrl.ipmsglim = path->msglim;
 879         if (userdata)
 880                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 881         parm->ctrl.ipflags1 = path->flags;
 882
 883         rc = iucv_call_b2f0(IUCV_ACCEPT, parm);
 884         if (!rc) {
 885                 path->private = private;
 886                 path->msglim = parm->ctrl.ipmsglim;
 887                 path->flags = parm->ctrl.ipflags1;
 888         }
 889 out:
 890         local_bh_enable();
 891         return rc;
 892 }
 893 EXPORT_SYMBOL(iucv_path_accept);
 894
 895 /**
 896  * iucv_path_connect
 897  * @path: address of iucv path structure
 898  * @handler: address of iucv handler structure
 899  * @userid: 8-byte user identification
 900  * @system: 8-byte target system identification
 901  * @userdata: 16 bytes of data reflected to the communication partner
 902  * @private: private data passed to interrupt handlers for this path
 903  *
 904  * This function establishes an IUCV path. Although the connect may complete
 905  * successfully, you are not able to use the path until you receive an IUCV
 906  * Connection Complete external interrupt.
 907  *
 908  * Returns the result of the CP IUCV call.
 909  */
 910 int iucv_path_connect(struct iucv_path *path, struct iucv_handler *handler,
 911                       u8 *userid, u8 *system, u8 *userdata,
 912                       void *private)
 913 {
 914         union iucv_param *parm;
 915         int rc;
 916
 917         spin_lock_bh(&iucv_table_lock);
 918         iucv_cleanup_queue();
 919         if (cpumask_empty(&iucv_buffer_cpumask)) {
 920                 rc = -EIO;
 921                 goto out;
 922         }
 923         parm = iucv_param[smp_processor_id()];
 924         memset(parm, 0, sizeof(union iucv_param));
 925         parm->ctrl.ipmsglim = path->msglim;
 926         parm->ctrl.ipflags1 = path->flags;
 927         if (userid) {
 928                 memcpy(parm->ctrl.ipvmid, userid, sizeof(parm->ctrl.ipvmid));
 929                 ASCEBC(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
 930                 EBC_TOUPPER(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
 931         }
 932         if (system) {
 933                 memcpy(parm->ctrl.iptarget, system,
 934                        sizeof(parm->ctrl.iptarget));
 935                 ASCEBC(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
 936                 EBC_TOUPPER(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
 937         }
 938         if (userdata)
 939                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 940
 941         rc = iucv_call_b2f0(IUCV_CONNECT, parm);
 942         if (!rc) {
 943                 if (parm->ctrl.ippathid < iucv_max_pathid) {
 944                         path->pathid = parm->ctrl.ippathid;
 945                         path->msglim = parm->ctrl.ipmsglim;
 946                         path->flags = parm->ctrl.ipflags1;
 947                         path->handler = handler;
 948                         path->private = private;
 949                         list_add_tail(&path->list, &handler->paths);
 950                         iucv_path_table[path->pathid] = path;
 951                 } else {
 952                         iucv_sever_pathid(parm->ctrl.ippathid,
 953                                           iucv_error_pathid);
 954                         rc = -EIO;
 955                 }
 956         }
 957 out:
 958         spin_unlock_bh(&iucv_table_lock);
 959         return rc;
 960 }
 961 EXPORT_SYMBOL(iucv_path_connect);
 962
 963 /**
 964  * iucv_path_quiesce:
 965  * @path: address of iucv path structure
 966  * @userdata: 16 bytes of data reflected to the communication partner
 967  *
 968  * This function temporarily suspends incoming messages on an IUCV path.
 969  * You can later reactivate the path by invoking the iucv_resume function.
 970  *
 971  * Returns the result from the CP IUCV call.
 972  */
 973 int iucv_path_quiesce(struct iucv_path *path, u8 *userdata)
 974 {
 975         union iucv_param *parm;
 976         int rc;
 977
 978         local_bh_disable();
 979         if (cpumask_empty(&iucv_buffer_cpumask)) {
 980                 rc = -EIO;
 981                 goto out;
 982         }
 983         parm = iucv_param[smp_processor_id()];
 984         memset(parm, 0, sizeof(union iucv_param));
 985         if (userdata)
 986                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
 987         parm->ctrl.ippathid = path->pathid;
 988         rc = iucv_call_b2f0(IUCV_QUIESCE, parm);
 989 out:
 990         local_bh_enable();
 991         return rc;
 992 }
 993 EXPORT_SYMBOL(iucv_path_quiesce);
 994
 995 /**
 996  * iucv_path_resume:
 997  * @path: address of iucv path structure
 998  * @userdata: 16 bytes of data reflected to the communication partner
 999  *
1000  * This function resumes incoming messages on an IUCV path that has
1001  * been stopped with iucv_path_quiesce.
1002  *
1003  * Returns the result from the CP IUCV call.
1004  */
1005 int iucv_path_resume(struct iucv_path *path, u8 *userdata)
1006 {
1007         union iucv_param *parm;
1008         int rc;
1009
1010         local_bh_disable();
1011         if (cpumask_empty(&iucv_buffer_cpumask)) {
1012                 rc = -EIO;
1013                 goto out;
1014         }
1015         parm = iucv_param[smp_processor_id()];
1016         memset(parm, 0, sizeof(union iucv_param));
1017         if (userdata)
1018                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
1019         parm->ctrl.ippathid = path->pathid;
1020         rc = iucv_call_b2f0(IUCV_RESUME, parm);
1021 out:
1022         local_bh_enable();
1023         return rc;
1024 }
1025
1026 /**
1027  * iucv_path_sever
1028  * @path: address of iucv path structure
1029  * @userdata: 16 bytes of data reflected to the communication partner
1030  *
1031  * This function terminates an IUCV path.
1032  *
1033  * Returns the result from the CP IUCV call.
1034  */
1035 int iucv_path_sever(struct iucv_path *path, u8 *userdata)
1036 {
1037         int rc;
1038
1039         preempt_disable();
1040         if (cpumask_empty(&iucv_buffer_cpumask)) {
1041                 rc = -EIO;
1042                 goto out;
1043         }
1044         if (iucv_active_cpu != smp_processor_id())
1045                 spin_lock_bh(&iucv_table_lock);
1046         rc = iucv_sever_pathid(path->pathid, userdata);
1047         iucv_path_table[path->pathid] = NULL;
1048         list_del_init(&path->list);
1049         if (iucv_active_cpu != smp_processor_id())
1050                 spin_unlock_bh(&iucv_table_lock);
1051 out:
1052         preempt_enable();
1053         return rc;
1054 }
1055 EXPORT_SYMBOL(iucv_path_sever);
1056
1057 /**
1058  * iucv_message_purge
1059  * @path: address of iucv path structure
1060  * @msg: address of iucv msg structure
1061  * @srccls: source class of message
1062  *
1063  * Cancels a message you have sent.
1064  *
1065  * Returns the result from the CP IUCV call.
1066  */
1067 int iucv_message_purge(struct iucv_path *path, struct iucv_message *msg,
1068                        u32 srccls)
1069 {
1070         union iucv_param *parm;
1071         int rc;
1072
1073         local_bh_disable();
1074         if (cpumask_empty(&iucv_buffer_cpumask)) {
1075                 rc = -EIO;
1076                 goto out;
1077         }
1078         parm = iucv_param[smp_processor_id()];
1079         memset(parm, 0, sizeof(union iucv_param));
1080         parm->purge.ippathid = path->pathid;
1081         parm->purge.ipmsgid = msg->id;
1082         parm->purge.ipsrccls = srccls;
1083         parm->purge.ipflags1 = IUCV_IPSRCCLS | IUCV_IPFGMID | IUCV_IPFGPID;
1084         rc = iucv_call_b2f0(IUCV_PURGE, parm);
1085         if (!rc) {
1086                 msg->audit = (*(u32 *) &parm->purge.ipaudit) >> 8;
1087                 msg->tag = parm->purge.ipmsgtag;
1088         }
1089 out:
1090         local_bh_enable();
1091         return rc;
1092 }
1093 EXPORT_SYMBOL(iucv_message_purge);
1094
1095 /**
1096  * iucv_message_receive_iprmdata
1097  * @path: address of iucv path structure
1098  * @msg: address of iucv msg structure
1099  * @flags: how the message is received (IUCV_IPBUFLST)
1100  * @buffer: address of data buffer or address of struct iucv_array
1101  * @size: length of data buffer
1102  * @residual:
1103  *
1104  * Internal function used by iucv_message_receive and __iucv_message_receive
1105  * to receive RMDATA data stored in struct iucv_message.
1106  */
1107 static int iucv_message_receive_iprmdata(struct iucv_path *path,
1108                                          struct iucv_message *msg,
1109                                          u8 flags, void *buffer,
1110                                          size_t size, size_t *residual)
1111 {
1112         struct iucv_array *array;
1113         u8 *rmmsg;
1114         size_t copy;
1115
1116         /*
1117          * Message is 8 bytes long and has been stored to the
1118          * message descriptor itself.
1119          */
1120         if (residual)
1121                 *residual = abs(size - 8);
1122         rmmsg = msg->rmmsg;
1123         if (flags & IUCV_IPBUFLST) {
1124                 /* Copy to struct iucv_array. */
1125                 size = (size < 8) ? size : 8;
1126                 for (array = buffer; size > 0; array++) {
1127                         copy = min_t(size_t, size, array->length);
1128                         memcpy(dma32_to_virt(array->address), rmmsg, copy);
1129                         rmmsg += copy;
1130                         size -= copy;
1131                 }
1132         } else {
1133                 /* Copy to direct buffer. */
1134                 memcpy(buffer, rmmsg, min_t(size_t, size, 8));
1135         }
1136         return 0;
1137 }
1138
1139 /**
1140  * __iucv_message_receive
1141  * @path: address of iucv path structure
1142  * @msg: address of iucv msg structure
1143  * @flags: how the message is received (IUCV_IPBUFLST)
1144  * @buffer: address of data buffer or address of struct iucv_array
1145  * @size: length of data buffer
1146  * @residual:
1147  *
1148  * This function receives messages that are being sent to you over
1149  * established paths. This function will deal with RMDATA messages
1150  * embedded in struct iucv_message as well.
1151  *
1152  * Locking:     no locking
1153  *
1154  * Returns the result from the CP IUCV call.
1155  */
1156 int __iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
1157                            u8 flags, void *buffer, size_t size, size_t *residual)
1158 {
1159         union iucv_param *parm;
1160         int rc;
1161
1162         if (msg->flags & IUCV_IPRMDATA)
1163                 return iucv_message_receive_iprmdata(path, msg, flags,
1164                                                      buffer, size, residual);
1165         if (cpumask_empty(&iucv_buffer_cpumask))
1166                 return -EIO;
1167
1168         parm = iucv_param[smp_processor_id()];
1169         memset(parm, 0, sizeof(union iucv_param));
1170         parm->db.ipbfadr1 = virt_to_dma32(buffer);
1171         parm->db.ipbfln1f = (u32) size;
1172         parm->db.ipmsgid = msg->id;
1173         parm->db.ippathid = path->pathid;
1174         parm->db.iptrgcls = msg->class;
1175         parm->db.ipflags1 = (flags | IUCV_IPFGPID |
1176                              IUCV_IPFGMID | IUCV_IPTRGCLS);
1177         rc = iucv_call_b2f0(IUCV_RECEIVE, parm);
1178         if (!rc || rc == 5) {
1179                 msg->flags = parm->db.ipflags1;
1180                 if (residual)
1181                         *residual = parm->db.ipbfln1f;
1182         }
1183         return rc;
1184 }
1185 EXPORT_SYMBOL(__iucv_message_receive);
1186
1187 /**
1188  * iucv_message_receive
1189  * @path: address of iucv path structure
1190  * @msg: address of iucv msg structure
1191  * @flags: how the message is received (IUCV_IPBUFLST)
1192  * @buffer: address of data buffer or address of struct iucv_array
1193  * @size: length of data buffer
1194  * @residual:
1195  *
1196  * This function receives messages that are being sent to you over
1197  * established paths. This function will deal with RMDATA messages
1198  * embedded in struct iucv_message as well.
1199  *
1200  * Locking:     local_bh_enable/local_bh_disable
1201  *
1202  * Returns the result from the CP IUCV call.
1203  */
1204 int iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
1205                          u8 flags, void *buffer, size_t size, size_t *residual)
1206 {
1207         int rc;
1208
1209         if (msg->flags & IUCV_IPRMDATA)
1210                 return iucv_message_receive_iprmdata(path, msg, flags,
1211                                                      buffer, size, residual);
1212         local_bh_disable();
1213         rc = __iucv_message_receive(path, msg, flags, buffer, size, residual);
1214         local_bh_enable();
1215         return rc;
1216 }
1217 EXPORT_SYMBOL(iucv_message_receive);
1218
1219 /**
1220  * iucv_message_reject
1221  * @path: address of iucv path structure
1222  * @msg: address of iucv msg structure
1223  *
1224  * The reject function refuses a specified message. Between the time you
1225  * are notified of a message and the time that you complete the message,
1226  * the message may be rejected.
1227  *
1228  * Returns the result from the CP IUCV call.
1229  */
1230 int iucv_message_reject(struct iucv_path *path, struct iucv_message *msg)
1231 {
1232         union iucv_param *parm;
1233         int rc;
1234
1235         local_bh_disable();
1236         if (cpumask_empty(&iucv_buffer_cpumask)) {
1237                 rc = -EIO;
1238                 goto out;
1239         }
1240         parm = iucv_param[smp_processor_id()];
1241         memset(parm, 0, sizeof(union iucv_param));
1242         parm->db.ippathid = path->pathid;
1243         parm->db.ipmsgid = msg->id;
1244         parm->db.iptrgcls = msg->class;
1245         parm->db.ipflags1 = (IUCV_IPTRGCLS | IUCV_IPFGMID | IUCV_IPFGPID);
1246         rc = iucv_call_b2f0(IUCV_REJECT, parm);
1247 out:
1248         local_bh_enable();
1249         return rc;
1250 }
1251 EXPORT_SYMBOL(iucv_message_reject);
1252
1253 /**
1254  * iucv_message_reply
1255  * @path: address of iucv path structure
1256  * @msg: address of iucv msg structure
1257  * @flags: how the reply is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1258  * @reply: address of reply data buffer or address of struct iucv_array
1259  * @size: length of reply data buffer
1260  *
1261  * This function responds to the two-way messages that you receive. You
1262  * must identify completely the message to which you wish to reply. ie,
1263  * pathid, msgid, and trgcls. Prmmsg signifies the data is moved into
1264  * the parameter list.
1265  *
1266  * Returns the result from the CP IUCV call.
1267  */
1268 int iucv_message_reply(struct iucv_path *path, struct iucv_message *msg,
1269                        u8 flags, void *reply, size_t size)
1270 {
1271         union iucv_param *parm;
1272         int rc;
1273
1274         local_bh_disable();
1275         if (cpumask_empty(&iucv_buffer_cpumask)) {
1276                 rc = -EIO;
1277                 goto out;
1278         }
1279         parm = iucv_param[smp_processor_id()];
1280         memset(parm, 0, sizeof(union iucv_param));
1281         if (flags & IUCV_IPRMDATA) {
1282                 parm->dpl.ippathid = path->pathid;
1283                 parm->dpl.ipflags1 = flags;
1284                 parm->dpl.ipmsgid = msg->id;
1285                 parm->dpl.iptrgcls = msg->class;
1286                 memcpy(parm->dpl.iprmmsg, reply, min_t(size_t, size, 8));
1287         } else {
1288                 parm->db.ipbfadr1 = virt_to_dma32(reply);
1289                 parm->db.ipbfln1f = (u32) size;
1290                 parm->db.ippathid = path->pathid;
1291                 parm->db.ipflags1 = flags;
1292                 parm->db.ipmsgid = msg->id;
1293                 parm->db.iptrgcls = msg->class;
1294         }
1295         rc = iucv_call_b2f0(IUCV_REPLY, parm);
1296 out:
1297         local_bh_enable();
1298         return rc;
1299 }
1300 EXPORT_SYMBOL(iucv_message_reply);
1301
1302 /**
1303  * __iucv_message_send
1304  * @path: address of iucv path structure
1305  * @msg: address of iucv msg structure
1306  * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1307  * @srccls: source class of message
1308  * @buffer: address of send buffer or address of struct iucv_array
1309  * @size: length of send buffer
1310  *
1311  * This function transmits data to another application. Data to be
1312  * transmitted is in a buffer and this is a one-way message and the
1313  * receiver will not reply to the message.
1314  *
1315  * Locking:     no locking
1316  *
1317  * Returns the result from the CP IUCV call.
1318  */
1319 int __iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
1320                       u8 flags, u32 srccls, void *buffer, size_t size)
1321 {
1322         union iucv_param *parm;
1323         int rc;
1324
1325         if (cpumask_empty(&iucv_buffer_cpumask)) {
1326                 rc = -EIO;
1327                 goto out;
1328         }
1329         parm = iucv_param[smp_processor_id()];
1330         memset(parm, 0, sizeof(union iucv_param));
1331         if (flags & IUCV_IPRMDATA) {
1332                 /* Message of 8 bytes can be placed into the parameter list. */
1333                 parm->dpl.ippathid = path->pathid;
1334                 parm->dpl.ipflags1 = flags | IUCV_IPNORPY;
1335                 parm->dpl.iptrgcls = msg->class;
1336                 parm->dpl.ipsrccls = srccls;
1337                 parm->dpl.ipmsgtag = msg->tag;
1338                 memcpy(parm->dpl.iprmmsg, buffer, 8);
1339         } else {
1340                 parm->db.ipbfadr1 = virt_to_dma32(buffer);
1341                 parm->db.ipbfln1f = (u32) size;
1342                 parm->db.ippathid = path->pathid;
1343                 parm->db.ipflags1 = flags | IUCV_IPNORPY;
1344                 parm->db.iptrgcls = msg->class;
1345                 parm->db.ipsrccls = srccls;
1346                 parm->db.ipmsgtag = msg->tag;
1347         }
1348         rc = iucv_call_b2f0(IUCV_SEND, parm);
1349         if (!rc)
1350                 msg->id = parm->db.ipmsgid;
1351 out:
1352         return rc;
1353 }
1354 EXPORT_SYMBOL(__iucv_message_send);
1355
1356 /**
1357  * iucv_message_send
1358  * @path: address of iucv path structure
1359  * @msg: address of iucv msg structure
1360  * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1361  * @srccls: source class of message
1362  * @buffer: address of send buffer or address of struct iucv_array
1363  * @size: length of send buffer
1364  *
1365  * This function transmits data to another application. Data to be
1366  * transmitted is in a buffer and this is a one-way message and the
1367  * receiver will not reply to the message.
1368  *
1369  * Locking:     local_bh_enable/local_bh_disable
1370  *
1371  * Returns the result from the CP IUCV call.
1372  */
1373 int iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
1374                       u8 flags, u32 srccls, void *buffer, size_t size)
1375 {
1376         int rc;
1377
1378         local_bh_disable();
1379         rc = __iucv_message_send(path, msg, flags, srccls, buffer, size);
1380         local_bh_enable();
1381         return rc;
1382 }
1383 EXPORT_SYMBOL(iucv_message_send);
1384
1385 /**
1386  * iucv_message_send2way
1387  * @path: address of iucv path structure
1388  * @msg: address of iucv msg structure
1389  * @flags: how the message is sent and the reply is received
1390  *         (IUCV_IPRMDATA, IUCV_IPBUFLST, IUCV_IPPRTY, IUCV_ANSLST)
1391  * @srccls: source class of message
1392  * @buffer: address of send buffer or address of struct iucv_array
1393  * @size: length of send buffer
1394  * @answer: address of answer buffer or address of struct iucv_array
1395  * @asize: size of reply buffer
1396  * @residual: ignored
1397  *
1398  * This function transmits data to another application. Data to be
1399  * transmitted is in a buffer. The receiver of the send is expected to
1400  * reply to the message and a buffer is provided into which IUCV moves
1401  * the reply to this message.
1402  *
1403  * Returns the result from the CP IUCV call.
1404  */
1405 int iucv_message_send2way(struct iucv_path *path, struct iucv_message *msg,
1406                           u8 flags, u32 srccls, void *buffer, size_t size,
1407                           void *answer, size_t asize, size_t *residual)
1408 {
1409         union iucv_param *parm;
1410         int rc;
1411
1412         local_bh_disable();
1413         if (cpumask_empty(&iucv_buffer_cpumask)) {
1414                 rc = -EIO;
1415                 goto out;
1416         }
1417         parm = iucv_param[smp_processor_id()];
1418         memset(parm, 0, sizeof(union iucv_param));
1419         if (flags & IUCV_IPRMDATA) {
1420                 parm->dpl.ippathid = path->pathid;
1421                 parm->dpl.ipflags1 = path->flags;       /* priority message */
1422                 parm->dpl.iptrgcls = msg->class;
1423                 parm->dpl.ipsrccls = srccls;
1424                 parm->dpl.ipmsgtag = msg->tag;
1425                 parm->dpl.ipbfadr2 = virt_to_dma32(answer);
1426                 parm->dpl.ipbfln2f = (u32) asize;
1427                 memcpy(parm->dpl.iprmmsg, buffer, 8);
1428         } else {
1429                 parm->db.ippathid = path->pathid;
1430                 parm->db.ipflags1 = path->flags;        /* priority message */
1431                 parm->db.iptrgcls = msg->class;
1432                 parm->db.ipsrccls = srccls;
1433                 parm->db.ipmsgtag = msg->tag;
1434                 parm->db.ipbfadr1 = virt_to_dma32(buffer);
1435                 parm->db.ipbfln1f = (u32) size;
1436                 parm->db.ipbfadr2 = virt_to_dma32(answer);
1437                 parm->db.ipbfln2f = (u32) asize;
1438         }
1439         rc = iucv_call_b2f0(IUCV_SEND, parm);
1440         if (!rc)
1441                 msg->id = parm->db.ipmsgid;
1442 out:
1443         local_bh_enable();
1444         return rc;
1445 }
1446 EXPORT_SYMBOL(iucv_message_send2way);
1447
1448 struct iucv_path_pending {
1449         u16 ippathid;
1450         u8  ipflags1;
1451         u8  iptype;
1452         u16 ipmsglim;
1453         u16 res1;
1454         u8  ipvmid[8];
1455         u8  ipuser[16];
1456         u32 res3;
1457         u8  ippollfg;
1458         u8  res4[3];
1459 } __packed;
1460
1461 /**
1462  * iucv_path_pending
1463  * @data: Pointer to external interrupt buffer
1464  *
1465  * Process connection pending work item. Called from tasklet while holding
1466  * iucv_table_lock.
1467  */
1468 static void iucv_path_pending(struct iucv_irq_data *data)
1469 {
1470         struct iucv_path_pending *ipp = (void *) data;
1471         struct iucv_handler *handler;
1472         struct iucv_path *path;
1473         char *error;
1474
1475         BUG_ON(iucv_path_table[ipp->ippathid]);
1476         /* New pathid, handler found. Create a new path struct. */
1477         error = iucv_error_no_memory;
1478         path = iucv_path_alloc(ipp->ipmsglim, ipp->ipflags1, GFP_ATOMIC);
1479         if (!path)
1480                 goto out_sever;
1481         path->pathid = ipp->ippathid;
1482         iucv_path_table[path->pathid] = path;
1483         EBCASC(ipp->ipvmid, 8);
1484
1485         /* Call registered handler until one is found that wants the path. */
1486         list_for_each_entry(handler, &iucv_handler_list, list) {
1487                 if (!handler->path_pending)
1488                         continue;
1489                 /*
1490                  * Add path to handler to allow a call to iucv_path_sever
1491                  * inside the path_pending function. If the handler returns
1492                  * an error remove the path from the handler again.
1493                  */
1494                 list_add(&path->list, &handler->paths);
1495                 path->handler = handler;
1496                 if (!handler->path_pending(path, ipp->ipvmid, ipp->ipuser))
1497                         return;
1498                 list_del(&path->list);
1499                 path->handler = NULL;
1500         }
1501         /* No handler wanted the path. */
1502         iucv_path_table[path->pathid] = NULL;
1503         iucv_path_free(path);
1504         error = iucv_error_no_listener;
1505 out_sever:
1506         iucv_sever_pathid(ipp->ippathid, error);
1507 }
1508
1509 struct iucv_path_complete {
1510         u16 ippathid;
1511         u8  ipflags1;
1512         u8  iptype;
1513         u16 ipmsglim;
1514         u16 res1;
1515         u8  res2[8];
1516         u8  ipuser[16];
1517         u32 res3;
1518         u8  ippollfg;
1519         u8  res4[3];
1520 } __packed;
1521
1522 /**
1523  * iucv_path_complete
1524  * @data: Pointer to external interrupt buffer
1525  *
1526  * Process connection complete work item. Called from tasklet while holding
1527  * iucv_table_lock.
1528  */
1529 static void iucv_path_complete(struct iucv_irq_data *data)
1530 {
1531         struct iucv_path_complete *ipc = (void *) data;
1532         struct iucv_path *path = iucv_path_table[ipc->ippathid];
1533
1534         if (path)
1535                 path->flags = ipc->ipflags1;
1536         if (path && path->handler && path->handler->path_complete)
1537                 path->handler->path_complete(path, ipc->ipuser);
1538 }
1539
1540 struct iucv_path_severed {
1541         u16 ippathid;
1542         u8  res1;
1543         u8  iptype;
1544         u32 res2;
1545         u8  res3[8];
1546         u8  ipuser[16];
1547         u32 res4;
1548         u8  ippollfg;
1549         u8  res5[3];
1550 } __packed;
1551
1552 /**
1553  * iucv_path_severed
1554  * @data: Pointer to external interrupt buffer
1555  *
1556  * Process connection severed work item. Called from tasklet while holding
1557  * iucv_table_lock.
1558  */
1559 static void iucv_path_severed(struct iucv_irq_data *data)
1560 {
1561         struct iucv_path_severed *ips = (void *) data;
1562         struct iucv_path *path = iucv_path_table[ips->ippathid];
1563
1564         if (!path || !path->handler)    /* Already severed */
1565                 return;
1566         if (path->handler->path_severed)
1567                 path->handler->path_severed(path, ips->ipuser);
1568         else {
1569                 iucv_sever_pathid(path->pathid, NULL);
1570                 iucv_path_table[path->pathid] = NULL;
1571                 list_del(&path->list);
1572                 iucv_path_free(path);
1573         }
1574 }
1575
1576 struct iucv_path_quiesced {
1577         u16 ippathid;
1578         u8  res1;
1579         u8  iptype;
1580         u32 res2;
1581         u8  res3[8];
1582         u8  ipuser[16];
1583         u32 res4;
1584         u8  ippollfg;
1585         u8  res5[3];
1586 } __packed;
1587
1588 /**
1589  * iucv_path_quiesced
1590  * @data: Pointer to external interrupt buffer
1591  *
1592  * Process connection quiesced work item. Called from tasklet while holding
1593  * iucv_table_lock.
1594  */
1595 static void iucv_path_quiesced(struct iucv_irq_data *data)
1596 {
1597         struct iucv_path_quiesced *ipq = (void *) data;
1598         struct iucv_path *path = iucv_path_table[ipq->ippathid];
1599
1600         if (path && path->handler && path->handler->path_quiesced)
1601                 path->handler->path_quiesced(path, ipq->ipuser);
1602 }
1603
1604 struct iucv_path_resumed {
1605         u16 ippathid;
1606         u8  res1;
1607         u8  iptype;
1608         u32 res2;
1609         u8  res3[8];
1610         u8  ipuser[16];
1611         u32 res4;
1612         u8  ippollfg;
1613         u8  res5[3];
1614 } __packed;
1615
1616 /**
1617  * iucv_path_resumed
1618  * @data: Pointer to external interrupt buffer
1619  *
1620  * Process connection resumed work item. Called from tasklet while holding
1621  * iucv_table_lock.
1622  */
1623 static void iucv_path_resumed(struct iucv_irq_data *data)
1624 {
1625         struct iucv_path_resumed *ipr = (void *) data;
1626         struct iucv_path *path = iucv_path_table[ipr->ippathid];
1627
1628         if (path && path->handler && path->handler->path_resumed)
1629                 path->handler->path_resumed(path, ipr->ipuser);
1630 }
1631
1632 struct iucv_message_complete {
1633         u16 ippathid;
1634         u8  ipflags1;
1635         u8  iptype;
1636         u32 ipmsgid;
1637         u32 ipaudit;
1638         u8  iprmmsg[8];
1639         u32 ipsrccls;
1640         u32 ipmsgtag;
1641         u32 res;
1642         u32 ipbfln2f;
1643         u8  ippollfg;
1644         u8  res2[3];
1645 } __packed;
1646
1647 /**
1648  * iucv_message_complete
1649  * @data: Pointer to external interrupt buffer
1650  *
1651  * Process message complete work item. Called from tasklet while holding
1652  * iucv_table_lock.
1653  */
1654 static void iucv_message_complete(struct iucv_irq_data *data)
1655 {
1656         struct iucv_message_complete *imc = (void *) data;
1657         struct iucv_path *path = iucv_path_table[imc->ippathid];
1658         struct iucv_message msg;
1659
1660         if (path && path->handler && path->handler->message_complete) {
1661                 msg.flags = imc->ipflags1;
1662                 msg.id = imc->ipmsgid;
1663                 msg.audit = imc->ipaudit;
1664                 memcpy(msg.rmmsg, imc->iprmmsg, 8);
1665                 msg.class = imc->ipsrccls;
1666                 msg.tag = imc->ipmsgtag;
1667                 msg.length = imc->ipbfln2f;
1668                 path->handler->message_complete(path, &msg);
1669         }
1670 }
1671
1672 struct iucv_message_pending {
1673         u16 ippathid;
1674         u8  ipflags1;
1675         u8  iptype;
1676         u32 ipmsgid;
1677         u32 iptrgcls;
1678         struct {
1679                 union {
1680                         u32 iprmmsg1_u32;
1681                         u8  iprmmsg1[4];
1682                 } ln1msg1;
1683                 union {
1684                         u32 ipbfln1f;
1685                         u8  iprmmsg2[4];
1686                 } ln1msg2;
1687         } rmmsg;
1688         u32 res1[3];
1689         u32 ipbfln2f;
1690         u8  ippollfg;
1691         u8  res2[3];
1692 } __packed;
1693
1694 /**
1695  * iucv_message_pending
1696  * @data: Pointer to external interrupt buffer
1697  *
1698  * Process message pending work item. Called from tasklet while holding
1699  * iucv_table_lock.
1700  */
1701 static void iucv_message_pending(struct iucv_irq_data *data)
1702 {
1703         struct iucv_message_pending *imp = (void *) data;
1704         struct iucv_path *path = iucv_path_table[imp->ippathid];
1705         struct iucv_message msg;
1706
1707         if (path && path->handler && path->handler->message_pending) {
1708                 msg.flags = imp->ipflags1;
1709                 msg.id = imp->ipmsgid;
1710                 msg.class = imp->iptrgcls;
1711                 if (imp->ipflags1 & IUCV_IPRMDATA) {
1712                         memcpy(msg.rmmsg, &imp->rmmsg, 8);
1713                         msg.length = 8;
1714                 } else
1715                         msg.length = imp->rmmsg.ln1msg2.ipbfln1f;
1716                 msg.reply_size = imp->ipbfln2f;
1717                 path->handler->message_pending(path, &msg);
1718         }
1719 }
1720
1721 /*
1722  * iucv_tasklet_fn:
1723  *
1724  * This tasklet loops over the queue of irq buffers created by
1725  * iucv_external_interrupt, calls the appropriate action handler
1726  * and then frees the buffer.
1727  */
1728 static void iucv_tasklet_fn(unsigned long ignored)
1729 {
1730         typedef void iucv_irq_fn(struct iucv_irq_data *);
1731         static iucv_irq_fn *irq_fn[] = {
1732                 [0x02] = iucv_path_complete,
1733                 [0x03] = iucv_path_severed,
1734                 [0x04] = iucv_path_quiesced,
1735                 [0x05] = iucv_path_resumed,
1736                 [0x06] = iucv_message_complete,
1737                 [0x07] = iucv_message_complete,
1738                 [0x08] = iucv_message_pending,
1739                 [0x09] = iucv_message_pending,
1740         };
1741         LIST_HEAD(task_queue);
1742         struct iucv_irq_list *p, *n;
1743
1744         /* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1745         if (!spin_trylock(&iucv_table_lock)) {
1746                 tasklet_schedule(&iucv_tasklet);
1747                 return;
1748         }
1749         iucv_active_cpu = smp_processor_id();
1750
1751         spin_lock_irq(&iucv_queue_lock);
1752         list_splice_init(&iucv_task_queue, &task_queue);
1753         spin_unlock_irq(&iucv_queue_lock);
1754
1755         list_for_each_entry_safe(p, n, &task_queue, list) {
1756                 list_del_init(&p->list);
1757                 irq_fn[p->data.iptype](&p->data);
1758                 kfree(p);
1759         }
1760
1761         iucv_active_cpu = -1;
1762         spin_unlock(&iucv_table_lock);
1763 }
1764
1765 /*
1766  * iucv_work_fn:
1767  *
1768  * This work function loops over the queue of path pending irq blocks
1769  * created by iucv_external_interrupt, calls the appropriate action
1770  * handler and then frees the buffer.
1771  */
1772 static void iucv_work_fn(struct work_struct *work)
1773 {
1774         LIST_HEAD(work_queue);
1775         struct iucv_irq_list *p, *n;
1776
1777         /* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1778         spin_lock_bh(&iucv_table_lock);
1779         iucv_active_cpu = smp_processor_id();
1780
1781         spin_lock_irq(&iucv_queue_lock);
1782         list_splice_init(&iucv_work_queue, &work_queue);
1783         spin_unlock_irq(&iucv_queue_lock);
1784
1785         iucv_cleanup_queue();
1786         list_for_each_entry_safe(p, n, &work_queue, list) {
1787                 list_del_init(&p->list);
1788                 iucv_path_pending(&p->data);
1789                 kfree(p);
1790         }
1791
1792         iucv_active_cpu = -1;
1793         spin_unlock_bh(&iucv_table_lock);
1794 }
1795
1796 /*
1797  * iucv_external_interrupt
1798  *
1799  * Handles external interrupts coming in from CP.
1800  * Places the interrupt buffer on a queue and schedules iucv_tasklet_fn().
1801  */
1802 static void iucv_external_interrupt(struct ext_code ext_code,
1803                                     unsigned int param32, unsigned long param64)
1804 {
1805         struct iucv_irq_data *p;
1806         struct iucv_irq_list *work;
1807
1808         inc_irq_stat(IRQEXT_IUC);
1809         p = iucv_irq_data[smp_processor_id()];
1810         if (p->ippathid >= iucv_max_pathid) {
1811                 WARN_ON(p->ippathid >= iucv_max_pathid);
1812                 iucv_sever_pathid(p->ippathid, iucv_error_no_listener);
1813                 return;
1814         }
1815         BUG_ON(p->iptype  < 0x01 || p->iptype > 0x09);
1816         work = kmalloc(sizeof(struct iucv_irq_list), GFP_ATOMIC);
1817         if (!work) {
1818                 pr_warn("iucv_external_interrupt: out of memory\n");
1819                 return;
1820         }
1821         memcpy(&work->data, p, sizeof(work->data));
1822         spin_lock(&iucv_queue_lock);
1823         if (p->iptype == 0x01) {
1824                 /* Path pending interrupt. */
1825                 list_add_tail(&work->list, &iucv_work_queue);
1826                 schedule_work(&iucv_work);
1827         } else {
1828                 /* The other interrupts. */
1829                 list_add_tail(&work->list, &iucv_task_queue);
1830                 tasklet_schedule(&iucv_tasklet);
1831         }
1832         spin_unlock(&iucv_queue_lock);
1833 }
1834
1835 struct iucv_interface iucv_if = {
1836         .message_receive = iucv_message_receive,
1837         .__message_receive = __iucv_message_receive,
1838         .message_reply = iucv_message_reply,
1839         .message_reject = iucv_message_reject,
1840         .message_send = iucv_message_send,
1841         .__message_send = __iucv_message_send,
1842         .message_send2way = iucv_message_send2way,
1843         .message_purge = iucv_message_purge,
1844         .path_accept = iucv_path_accept,
1845         .path_connect = iucv_path_connect,
1846         .path_quiesce = iucv_path_quiesce,
1847         .path_resume = iucv_path_resume,
1848         .path_sever = iucv_path_sever,
1849         .iucv_register = iucv_register,
1850         .iucv_unregister = iucv_unregister,
1851         .bus = NULL,
1852         .root = NULL,
1853 };
1854 EXPORT_SYMBOL(iucv_if);
1855
1856 static enum cpuhp_state iucv_online;
1857 /**
1858  * iucv_init
1859  *
1860  * Allocates and initializes various data structures.
1861  */
1862 static int __init iucv_init(void)
1863 {
1864         int rc;
1865
1866         if (!MACHINE_IS_VM) {
1867                 rc = -EPROTONOSUPPORT;
1868                 goto out;
1869         }
1870         system_ctl_set_bit(0, CR0_IUCV_BIT);
1871         rc = iucv_query_maxconn();
1872         if (rc)
1873                 goto out_ctl;
1874         rc = register_external_irq(EXT_IRQ_IUCV, iucv_external_interrupt);
1875         if (rc)
1876                 goto out_ctl;
1877         iucv_root = root_device_register("iucv");
1878         if (IS_ERR(iucv_root)) {
1879                 rc = PTR_ERR(iucv_root);
1880                 goto out_int;
1881         }
1882
1883         rc = cpuhp_setup_state(CPUHP_NET_IUCV_PREPARE, "net/iucv:prepare",
1884                                iucv_cpu_prepare, iucv_cpu_dead);
1885         if (rc)
1886                 goto out_dev;
1887         rc = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "net/iucv:online",
1888                                iucv_cpu_online, iucv_cpu_down_prep);
1889         if (rc < 0)
1890                 goto out_prep;
1891         iucv_online = rc;
1892
1893         rc = register_reboot_notifier(&iucv_reboot_notifier);
1894         if (rc)
1895                 goto out_remove_hp;
1896         ASCEBC(iucv_error_no_listener, 16);
1897         ASCEBC(iucv_error_no_memory, 16);
1898         ASCEBC(iucv_error_pathid, 16);
1899         iucv_available = 1;
1900         rc = bus_register(&iucv_bus);
1901         if (rc)
1902                 goto out_reboot;
1903         iucv_if.root = iucv_root;
1904         iucv_if.bus = &iucv_bus;
1905         return 0;
1906
1907 out_reboot:
1908         unregister_reboot_notifier(&iucv_reboot_notifier);
1909 out_remove_hp:
1910         cpuhp_remove_state(iucv_online);
1911 out_prep:
1912         cpuhp_remove_state(CPUHP_NET_IUCV_PREPARE);
1913 out_dev:
1914         root_device_unregister(iucv_root);
1915 out_int:
1916         unregister_external_irq(EXT_IRQ_IUCV, iucv_external_interrupt);
1917 out_ctl:
1918         system_ctl_clear_bit(0, 1);
1919 out:
1920         return rc;
1921 }
1922
1923 /**
1924  * iucv_exit
1925  *
1926  * Frees everything allocated from iucv_init.
1927  */
1928 static void __exit iucv_exit(void)
1929 {
1930         struct iucv_irq_list *p, *n;
1931
1932         spin_lock_irq(&iucv_queue_lock);
1933         list_for_each_entry_safe(p, n, &iucv_task_queue, list)
1934                 kfree(p);
1935         list_for_each_entry_safe(p, n, &iucv_work_queue, list)
1936                 kfree(p);
1937         spin_unlock_irq(&iucv_queue_lock);
1938         unregister_reboot_notifier(&iucv_reboot_notifier);
1939
1940         cpuhp_remove_state_nocalls(iucv_online);
1941         cpuhp_remove_state(CPUHP_NET_IUCV_PREPARE);
1942         root_device_unregister(iucv_root);
1943         bus_unregister(&iucv_bus);
1944         unregister_external_irq(EXT_IRQ_IUCV, iucv_external_interrupt);
1945 }
1946
1947 subsys_initcall(iucv_init);
1948 module_exit(iucv_exit);
1949
1950 MODULE_AUTHOR("(C) 2001 IBM Corp. by Fritz Elfert <[email protected]>");
1951 MODULE_DESCRIPTION("Linux for S/390 IUCV lowlevel driver");
1952 MODULE_LICENSE("GPL");