Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
[linux-2.6] / net / iucv / iucv.c
1 /*
2  * IUCV base infrastructure.
3  *
4  * Copyright 2001, 2006 IBM Deutschland Entwicklung GmbH, IBM Corporation
5  * Author(s):
6  *    Original source:
7  *      Alan Altmark (Alan_Altmark@us.ibm.com)  Sept. 2000
8  *      Xenia Tkatschow (xenia@us.ibm.com)
9  *    2Gb awareness and general cleanup:
10  *      Fritz Elfert (elfert@de.ibm.com, felfert@millenux.com)
11  *    Rewritten for af_iucv:
12  *      Martin Schwidefsky <schwidefsky@de.ibm.com>
13  *
14  * Documentation used:
15  *    The original source
16  *    CP Programming Service, IBM document # SC24-5760
17  *
18  * This program is free software; you can redistribute it and/or modify
19  * it under the terms of the GNU General Public License as published by
20  * the Free Software Foundation; either version 2, or (at your option)
21  * any later version.
22  *
23  * This program is distributed in the hope that it will be useful,
24  * but WITHOUT ANY WARRANTY; without even the implied warranty of
25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
26  * GNU General Public License for more details.
27  *
28  * You should have received a copy of the GNU General Public License
29  * along with this program; if not, write to the Free Software
30  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
31  */
32
33 #include <linux/module.h>
34 #include <linux/moduleparam.h>
35 #include <linux/spinlock.h>
36 #include <linux/kernel.h>
37 #include <linux/slab.h>
38 #include <linux/init.h>
39 #include <linux/interrupt.h>
40 #include <linux/list.h>
41 #include <linux/errno.h>
42 #include <linux/err.h>
43 #include <linux/device.h>
44 #include <linux/cpu.h>
45 #include <net/iucv/iucv.h>
46 #include <asm/atomic.h>
47 #include <asm/ebcdic.h>
48 #include <asm/io.h>
49 #include <asm/s390_ext.h>
50 #include <asm/s390_rdev.h>
51 #include <asm/smp.h>
52
53 /*
54  * FLAGS:
55  * All flags are defined in the field IPFLAGS1 of each function
56  * and can be found in CP Programming Services.
57  * IPSRCCLS - Indicates you have specified a source class.
58  * IPTRGCLS - Indicates you have specified a target class.
59  * IPFGPID  - Indicates you have specified a pathid.
60  * IPFGMID  - Indicates you have specified a message ID.
61  * IPNORPY  - Indicates a one-way message. No reply expected.
62  * IPALL    - Indicates that all paths are affected.
63  */
64 #define IUCV_IPSRCCLS   0x01
65 #define IUCV_IPTRGCLS   0x01
66 #define IUCV_IPFGPID    0x02
67 #define IUCV_IPFGMID    0x04
68 #define IUCV_IPNORPY    0x10
69 #define IUCV_IPALL      0x80
70
71 static int iucv_bus_match(struct device *dev, struct device_driver *drv)
72 {
73         return 0;
74 }
75
76 struct bus_type iucv_bus = {
77         .name = "iucv",
78         .match = iucv_bus_match,
79 };
80 EXPORT_SYMBOL(iucv_bus);
81
82 struct device *iucv_root;
83 EXPORT_SYMBOL(iucv_root);
84
85 static int iucv_available;
86
87 /* General IUCV interrupt structure */
88 struct iucv_irq_data {
89         u16 ippathid;
90         u8  ipflags1;
91         u8  iptype;
92         u32 res2[8];
93 };
94
95 struct iucv_irq_list {
96         struct list_head list;
97         struct iucv_irq_data data;
98 };
99
100 static struct iucv_irq_data *iucv_irq_data;
101 static cpumask_t iucv_buffer_cpumask = CPU_MASK_NONE;
102 static cpumask_t iucv_irq_cpumask = CPU_MASK_NONE;
103
104 /*
105  * Queue of interrupt buffers lock for delivery via the tasklet
106  * (fast but can't call smp_call_function).
107  */
108 static LIST_HEAD(iucv_task_queue);
109
110 /*
111  * The tasklet for fast delivery of iucv interrupts.
112  */
113 static void iucv_tasklet_fn(unsigned long);
114 static DECLARE_TASKLET(iucv_tasklet, iucv_tasklet_fn,0);
115
116 /*
117  * Queue of interrupt buffers for delivery via a work queue
118  * (slower but can call smp_call_function).
119  */
120 static LIST_HEAD(iucv_work_queue);
121
122 /*
123  * The work element to deliver path pending interrupts.
124  */
125 static void iucv_work_fn(struct work_struct *work);
126 static DECLARE_WORK(iucv_work, iucv_work_fn);
127
128 /*
129  * Spinlock protecting task and work queue.
130  */
131 static DEFINE_SPINLOCK(iucv_queue_lock);
132
133 enum iucv_command_codes {
134         IUCV_QUERY = 0,
135         IUCV_RETRIEVE_BUFFER = 2,
136         IUCV_SEND = 4,
137         IUCV_RECEIVE = 5,
138         IUCV_REPLY = 6,
139         IUCV_REJECT = 8,
140         IUCV_PURGE = 9,
141         IUCV_ACCEPT = 10,
142         IUCV_CONNECT = 11,
143         IUCV_DECLARE_BUFFER = 12,
144         IUCV_QUIESCE = 13,
145         IUCV_RESUME = 14,
146         IUCV_SEVER = 15,
147         IUCV_SETMASK = 16,
148 };
149
150 /*
151  * Error messages that are used with the iucv_sever function. They get
152  * converted to EBCDIC.
153  */
154 static char iucv_error_no_listener[16] = "NO LISTENER";
155 static char iucv_error_no_memory[16] = "NO MEMORY";
156 static char iucv_error_pathid[16] = "INVALID PATHID";
157
158 /*
159  * iucv_handler_list: List of registered handlers.
160  */
161 static LIST_HEAD(iucv_handler_list);
162
163 /*
164  * iucv_path_table: an array of iucv_path structures.
165  */
166 static struct iucv_path **iucv_path_table;
167 static unsigned long iucv_max_pathid;
168
169 /*
170  * iucv_lock: spinlock protecting iucv_handler_list and iucv_pathid_table
171  */
172 static DEFINE_SPINLOCK(iucv_table_lock);
173
174 /*
175  * iucv_active_cpu: contains the number of the cpu executing the tasklet
176  * or the work handler. Needed for iucv_path_sever called from tasklet.
177  */
178 static int iucv_active_cpu = -1;
179
180 /*
181  * Mutex and wait queue for iucv_register/iucv_unregister.
182  */
183 static DEFINE_MUTEX(iucv_register_mutex);
184
185 /*
186  * Counter for number of non-smp capable handlers.
187  */
188 static int iucv_nonsmp_handler;
189
190 /*
191  * IUCV control data structure. Used by iucv_path_accept, iucv_path_connect,
192  * iucv_path_quiesce and iucv_path_sever.
193  */
194 struct iucv_cmd_control {
195         u16 ippathid;
196         u8  ipflags1;
197         u8  iprcode;
198         u16 ipmsglim;
199         u16 res1;
200         u8  ipvmid[8];
201         u8  ipuser[16];
202         u8  iptarget[8];
203 } __attribute__ ((packed,aligned(8)));
204
205 /*
206  * Data in parameter list iucv structure. Used by iucv_message_send,
207  * iucv_message_send2way and iucv_message_reply.
208  */
209 struct iucv_cmd_dpl {
210         u16 ippathid;
211         u8  ipflags1;
212         u8  iprcode;
213         u32 ipmsgid;
214         u32 iptrgcls;
215         u8  iprmmsg[8];
216         u32 ipsrccls;
217         u32 ipmsgtag;
218         u32 ipbfadr2;
219         u32 ipbfln2f;
220         u32 res;
221 } __attribute__ ((packed,aligned(8)));
222
223 /*
224  * Data in buffer iucv structure. Used by iucv_message_receive,
225  * iucv_message_reject, iucv_message_send, iucv_message_send2way
226  * and iucv_declare_cpu.
227  */
228 struct iucv_cmd_db {
229         u16 ippathid;
230         u8  ipflags1;
231         u8  iprcode;
232         u32 ipmsgid;
233         u32 iptrgcls;
234         u32 ipbfadr1;
235         u32 ipbfln1f;
236         u32 ipsrccls;
237         u32 ipmsgtag;
238         u32 ipbfadr2;
239         u32 ipbfln2f;
240         u32 res;
241 } __attribute__ ((packed,aligned(8)));
242
243 /*
244  * Purge message iucv structure. Used by iucv_message_purge.
245  */
246 struct iucv_cmd_purge {
247         u16 ippathid;
248         u8  ipflags1;
249         u8  iprcode;
250         u32 ipmsgid;
251         u8  ipaudit[3];
252         u8  res1[5];
253         u32 res2;
254         u32 ipsrccls;
255         u32 ipmsgtag;
256         u32 res3[3];
257 } __attribute__ ((packed,aligned(8)));
258
259 /*
260  * Set mask iucv structure. Used by iucv_enable_cpu.
261  */
262 struct iucv_cmd_set_mask {
263         u8  ipmask;
264         u8  res1[2];
265         u8  iprcode;
266         u32 res2[9];
267 } __attribute__ ((packed,aligned(8)));
268
269 union iucv_param {
270         struct iucv_cmd_control ctrl;
271         struct iucv_cmd_dpl dpl;
272         struct iucv_cmd_db db;
273         struct iucv_cmd_purge purge;
274         struct iucv_cmd_set_mask set_mask;
275 };
276
277 /*
278  * Anchor for per-cpu IUCV command parameter block.
279  */
280 static union iucv_param *iucv_param;
281
282 /**
283  * iucv_call_b2f0
284  * @code: identifier of IUCV call to CP.
285  * @parm: pointer to a struct iucv_parm block
286  *
287  * Calls CP to execute IUCV commands.
288  *
289  * Returns the result of the CP IUCV call.
290  */
291 static inline int iucv_call_b2f0(int command, union iucv_param *parm)
292 {
293         register unsigned long reg0 asm ("0");
294         register unsigned long reg1 asm ("1");
295         int ccode;
296
297         reg0 = command;
298         reg1 = virt_to_phys(parm);
299         asm volatile(
300                 "       .long 0xb2f01000\n"
301                 "       ipm     %0\n"
302                 "       srl     %0,28\n"
303                 : "=d" (ccode), "=m" (*parm), "+d" (reg0), "+a" (reg1)
304                 :  "m" (*parm) : "cc");
305         return (ccode == 1) ? parm->ctrl.iprcode : ccode;
306 }
307
308 /**
309  * iucv_query_maxconn
310  *
311  * Determines the maximum number of connections that may be established.
312  *
313  * Returns the maximum number of connections or -EPERM is IUCV is not
314  * available.
315  */
316 static int iucv_query_maxconn(void)
317 {
318         register unsigned long reg0 asm ("0");
319         register unsigned long reg1 asm ("1");
320         void *param;
321         int ccode;
322
323         param = kzalloc(sizeof(union iucv_param), GFP_KERNEL|GFP_DMA);
324         if (!param)
325                 return -ENOMEM;
326         reg0 = IUCV_QUERY;
327         reg1 = (unsigned long) param;
328         asm volatile (
329                 "       .long   0xb2f01000\n"
330                 "       ipm     %0\n"
331                 "       srl     %0,28\n"
332                 : "=d" (ccode), "+d" (reg0), "+d" (reg1) : : "cc");
333         if (ccode == 0)
334                 iucv_max_pathid = reg0;
335         kfree(param);
336         return ccode ? -EPERM : 0;
337 }
338
339 /**
340  * iucv_allow_cpu
341  * @data: unused
342  *
343  * Allow iucv interrupts on this cpu.
344  */
345 static void iucv_allow_cpu(void *data)
346 {
347         int cpu = smp_processor_id();
348         union iucv_param *parm;
349
350         /*
351          * Enable all iucv interrupts.
352          * ipmask contains bits for the different interrupts
353          *      0x80 - Flag to allow nonpriority message pending interrupts
354          *      0x40 - Flag to allow priority message pending interrupts
355          *      0x20 - Flag to allow nonpriority message completion interrupts
356          *      0x10 - Flag to allow priority message completion interrupts
357          *      0x08 - Flag to allow IUCV control interrupts
358          */
359         parm = percpu_ptr(iucv_param, smp_processor_id());
360         memset(parm, 0, sizeof(union iucv_param));
361         parm->set_mask.ipmask = 0xf8;
362         iucv_call_b2f0(IUCV_SETMASK, parm);
363
364         /* Set indication that iucv interrupts are allowed for this cpu. */
365         cpu_set(cpu, iucv_irq_cpumask);
366 }
367
368 /**
369  * iucv_block_cpu
370  * @data: unused
371  *
372  * Block iucv interrupts on this cpu.
373  */
374 static void iucv_block_cpu(void *data)
375 {
376         int cpu = smp_processor_id();
377         union iucv_param *parm;
378
379         /* Disable all iucv interrupts. */
380         parm = percpu_ptr(iucv_param, smp_processor_id());
381         memset(parm, 0, sizeof(union iucv_param));
382         iucv_call_b2f0(IUCV_SETMASK, parm);
383
384         /* Clear indication that iucv interrupts are allowed for this cpu. */
385         cpu_clear(cpu, iucv_irq_cpumask);
386 }
387
388 /**
389  * iucv_declare_cpu
390  * @data: unused
391  *
392  * Declare a interupt buffer on this cpu.
393  */
394 static void iucv_declare_cpu(void *data)
395 {
396         int cpu = smp_processor_id();
397         union iucv_param *parm;
398         int rc;
399
400         if (cpu_isset(cpu, iucv_buffer_cpumask))
401                 return;
402
403         /* Declare interrupt buffer. */
404         parm = percpu_ptr(iucv_param, cpu);
405         memset(parm, 0, sizeof(union iucv_param));
406         parm->db.ipbfadr1 = virt_to_phys(percpu_ptr(iucv_irq_data, cpu));
407         rc = iucv_call_b2f0(IUCV_DECLARE_BUFFER, parm);
408         if (rc) {
409                 char *err = "Unknown";
410                 switch (rc) {
411                 case 0x03:
412                         err = "Directory error";
413                         break;
414                 case 0x0a:
415                         err = "Invalid length";
416                         break;
417                 case 0x13:
418                         err = "Buffer already exists";
419                         break;
420                 case 0x3e:
421                         err = "Buffer overlap";
422                         break;
423                 case 0x5c:
424                         err = "Paging or storage error";
425                         break;
426                 }
427                 printk(KERN_WARNING "iucv_register: iucv_declare_buffer "
428                        "on cpu %i returned error 0x%02x (%s)\n", cpu, rc, err);
429                 return;
430         }
431
432         /* Set indication that an iucv buffer exists for this cpu. */
433         cpu_set(cpu, iucv_buffer_cpumask);
434
435         if (iucv_nonsmp_handler == 0 || cpus_empty(iucv_irq_cpumask))
436                 /* Enable iucv interrupts on this cpu. */
437                 iucv_allow_cpu(NULL);
438         else
439                 /* Disable iucv interrupts on this cpu. */
440                 iucv_block_cpu(NULL);
441 }
442
443 /**
444  * iucv_retrieve_cpu
445  * @data: unused
446  *
447  * Retrieve interrupt buffer on this cpu.
448  */
449 static void iucv_retrieve_cpu(void *data)
450 {
451         int cpu = smp_processor_id();
452         union iucv_param *parm;
453
454         if (!cpu_isset(cpu, iucv_buffer_cpumask))
455                 return;
456
457         /* Block iucv interrupts. */
458         iucv_block_cpu(NULL);
459
460         /* Retrieve interrupt buffer. */
461         parm = percpu_ptr(iucv_param, cpu);
462         iucv_call_b2f0(IUCV_RETRIEVE_BUFFER, parm);
463
464         /* Clear indication that an iucv buffer exists for this cpu. */
465         cpu_clear(cpu, iucv_buffer_cpumask);
466 }
467
468 /**
469  * iucv_setmask_smp
470  *
471  * Allow iucv interrupts on all cpus.
472  */
473 static void iucv_setmask_mp(void)
474 {
475         int cpu;
476
477         preempt_disable();
478         for_each_online_cpu(cpu)
479                 /* Enable all cpus with a declared buffer. */
480                 if (cpu_isset(cpu, iucv_buffer_cpumask) &&
481                     !cpu_isset(cpu, iucv_irq_cpumask))
482                         smp_call_function_on(iucv_allow_cpu, NULL, 0, 1, cpu);
483         preempt_enable();
484 }
485
486 /**
487  * iucv_setmask_up
488  *
489  * Allow iucv interrupts on a single cpu.
490  */
491 static void iucv_setmask_up(void)
492 {
493         cpumask_t cpumask;
494         int cpu;
495
496         /* Disable all cpu but the first in cpu_irq_cpumask. */
497         cpumask = iucv_irq_cpumask;
498         cpu_clear(first_cpu(iucv_irq_cpumask), cpumask);
499         for_each_cpu_mask(cpu, cpumask)
500                 smp_call_function_on(iucv_block_cpu, NULL, 0, 1, cpu);
501 }
502
503 /**
504  * iucv_enable
505  *
506  * This function makes iucv ready for use. It allocates the pathid
507  * table, declares an iucv interrupt buffer and enables the iucv
508  * interrupts. Called when the first user has registered an iucv
509  * handler.
510  */
511 static int iucv_enable(void)
512 {
513         size_t alloc_size;
514         int cpu, rc;
515
516         rc = -ENOMEM;
517         alloc_size = iucv_max_pathid * sizeof(struct iucv_path);
518         iucv_path_table = kzalloc(alloc_size, GFP_KERNEL);
519         if (!iucv_path_table)
520                 goto out;
521         /* Declare per cpu buffers. */
522         rc = -EIO;
523         preempt_disable();
524         for_each_online_cpu(cpu)
525                 smp_call_function_on(iucv_declare_cpu, NULL, 0, 1, cpu);
526         preempt_enable();
527         if (cpus_empty(iucv_buffer_cpumask))
528                 /* No cpu could declare an iucv buffer. */
529                 goto out_path;
530         return 0;
531
532 out_path:
533         kfree(iucv_path_table);
534 out:
535         return rc;
536 }
537
538 /**
539  * iucv_disable
540  *
541  * This function shuts down iucv. It disables iucv interrupts, retrieves
542  * the iucv interrupt buffer and frees the pathid table. Called after the
543  * last user unregister its iucv handler.
544  */
545 static void iucv_disable(void)
546 {
547         on_each_cpu(iucv_retrieve_cpu, NULL, 0, 1);
548         kfree(iucv_path_table);
549 }
550
551 static int __cpuinit iucv_cpu_notify(struct notifier_block *self,
552                                      unsigned long action, void *hcpu)
553 {
554         cpumask_t cpumask;
555         long cpu = (long) hcpu;
556
557         switch (action) {
558         case CPU_UP_PREPARE:
559         case CPU_UP_PREPARE_FROZEN:
560                 if (!percpu_populate(iucv_irq_data,
561                                      sizeof(struct iucv_irq_data),
562                                      GFP_KERNEL|GFP_DMA, cpu))
563                         return NOTIFY_BAD;
564                 if (!percpu_populate(iucv_param, sizeof(union iucv_param),
565                                      GFP_KERNEL|GFP_DMA, cpu)) {
566                         percpu_depopulate(iucv_irq_data, cpu);
567                         return NOTIFY_BAD;
568                 }
569                 break;
570         case CPU_UP_CANCELED:
571         case CPU_UP_CANCELED_FROZEN:
572         case CPU_DEAD:
573         case CPU_DEAD_FROZEN:
574                 percpu_depopulate(iucv_param, cpu);
575                 percpu_depopulate(iucv_irq_data, cpu);
576                 break;
577         case CPU_ONLINE:
578         case CPU_ONLINE_FROZEN:
579         case CPU_DOWN_FAILED:
580         case CPU_DOWN_FAILED_FROZEN:
581                 smp_call_function_on(iucv_declare_cpu, NULL, 0, 1, cpu);
582                 break;
583         case CPU_DOWN_PREPARE:
584         case CPU_DOWN_PREPARE_FROZEN:
585                 cpumask = iucv_buffer_cpumask;
586                 cpu_clear(cpu, cpumask);
587                 if (cpus_empty(cpumask))
588                         /* Can't offline last IUCV enabled cpu. */
589                         return NOTIFY_BAD;
590                 smp_call_function_on(iucv_retrieve_cpu, NULL, 0, 1, cpu);
591                 if (cpus_empty(iucv_irq_cpumask))
592                         smp_call_function_on(iucv_allow_cpu, NULL, 0, 1,
593                                              first_cpu(iucv_buffer_cpumask));
594                 break;
595         }
596         return NOTIFY_OK;
597 }
598
599 static struct notifier_block __cpuinitdata iucv_cpu_notifier = {
600         .notifier_call = iucv_cpu_notify,
601 };
602
603 /**
604  * iucv_sever_pathid
605  * @pathid: path identification number.
606  * @userdata: 16-bytes of user data.
607  *
608  * Sever an iucv path to free up the pathid. Used internally.
609  */
610 static int iucv_sever_pathid(u16 pathid, u8 userdata[16])
611 {
612         union iucv_param *parm;
613
614         parm = percpu_ptr(iucv_param, smp_processor_id());
615         memset(parm, 0, sizeof(union iucv_param));
616         if (userdata)
617                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
618         parm->ctrl.ippathid = pathid;
619         return iucv_call_b2f0(IUCV_SEVER, parm);
620 }
621
622 #ifdef CONFIG_SMP
623 /**
624  * __iucv_cleanup_queue
625  * @dummy: unused dummy argument
626  *
627  * Nop function called via smp_call_function to force work items from
628  * pending external iucv interrupts to the work queue.
629  */
630 static void __iucv_cleanup_queue(void *dummy)
631 {
632 }
633 #endif
634
635 /**
636  * iucv_cleanup_queue
637  *
638  * Function called after a path has been severed to find all remaining
639  * work items for the now stale pathid. The caller needs to hold the
640  * iucv_table_lock.
641  */
642 static void iucv_cleanup_queue(void)
643 {
644         struct iucv_irq_list *p, *n;
645
646         /*
647          * When a path is severed, the pathid can be reused immediatly
648          * on a iucv connect or a connection pending interrupt. Remove
649          * all entries from the task queue that refer to a stale pathid
650          * (iucv_path_table[ix] == NULL). Only then do the iucv connect
651          * or deliver the connection pending interrupt. To get all the
652          * pending interrupts force them to the work queue by calling
653          * an empty function on all cpus.
654          */
655         smp_call_function(__iucv_cleanup_queue, NULL, 0, 1);
656         spin_lock_irq(&iucv_queue_lock);
657         list_for_each_entry_safe(p, n, &iucv_task_queue, list) {
658                 /* Remove stale work items from the task queue. */
659                 if (iucv_path_table[p->data.ippathid] == NULL) {
660                         list_del(&p->list);
661                         kfree(p);
662                 }
663         }
664         spin_unlock_irq(&iucv_queue_lock);
665 }
666
667 /**
668  * iucv_register:
669  * @handler: address of iucv handler structure
670  * @smp: != 0 indicates that the handler can deal with out of order messages
671  *
672  * Registers a driver with IUCV.
673  *
674  * Returns 0 on success, -ENOMEM if the memory allocation for the pathid
675  * table failed, or -EIO if IUCV_DECLARE_BUFFER failed on all cpus.
676  */
677 int iucv_register(struct iucv_handler *handler, int smp)
678 {
679         int rc;
680
681         if (!iucv_available)
682                 return -ENOSYS;
683         mutex_lock(&iucv_register_mutex);
684         if (!smp)
685                 iucv_nonsmp_handler++;
686         if (list_empty(&iucv_handler_list)) {
687                 rc = iucv_enable();
688                 if (rc)
689                         goto out_mutex;
690         } else if (!smp && iucv_nonsmp_handler == 1)
691                 iucv_setmask_up();
692         INIT_LIST_HEAD(&handler->paths);
693
694         spin_lock_irq(&iucv_table_lock);
695         list_add_tail(&handler->list, &iucv_handler_list);
696         spin_unlock_irq(&iucv_table_lock);
697         rc = 0;
698 out_mutex:
699         mutex_unlock(&iucv_register_mutex);
700         return rc;
701 }
702 EXPORT_SYMBOL(iucv_register);
703
704 /**
705  * iucv_unregister
706  * @handler:  address of iucv handler structure
707  * @smp: != 0 indicates that the handler can deal with out of order messages
708  *
709  * Unregister driver from IUCV.
710  */
711 void iucv_unregister(struct iucv_handler *handler, int smp)
712 {
713         struct iucv_path *p, *n;
714
715         mutex_lock(&iucv_register_mutex);
716         spin_lock_bh(&iucv_table_lock);
717         /* Remove handler from the iucv_handler_list. */
718         list_del_init(&handler->list);
719         /* Sever all pathids still refering to the handler. */
720         list_for_each_entry_safe(p, n, &handler->paths, list) {
721                 iucv_sever_pathid(p->pathid, NULL);
722                 iucv_path_table[p->pathid] = NULL;
723                 list_del(&p->list);
724                 iucv_path_free(p);
725         }
726         spin_unlock_bh(&iucv_table_lock);
727         if (!smp)
728                 iucv_nonsmp_handler--;
729         if (list_empty(&iucv_handler_list))
730                 iucv_disable();
731         else if (!smp && iucv_nonsmp_handler == 0)
732                 iucv_setmask_mp();
733         mutex_unlock(&iucv_register_mutex);
734 }
735 EXPORT_SYMBOL(iucv_unregister);
736
737 /**
738  * iucv_path_accept
739  * @path: address of iucv path structure
740  * @handler: address of iucv handler structure
741  * @userdata: 16 bytes of data reflected to the communication partner
742  * @private: private data passed to interrupt handlers for this path
743  *
744  * This function is issued after the user received a connection pending
745  * external interrupt and now wishes to complete the IUCV communication path.
746  *
747  * Returns the result of the CP IUCV call.
748  */
749 int iucv_path_accept(struct iucv_path *path, struct iucv_handler *handler,
750                      u8 userdata[16], void *private)
751 {
752         union iucv_param *parm;
753         int rc;
754
755         local_bh_disable();
756         /* Prepare parameter block. */
757         parm = percpu_ptr(iucv_param, smp_processor_id());
758         memset(parm, 0, sizeof(union iucv_param));
759         parm->ctrl.ippathid = path->pathid;
760         parm->ctrl.ipmsglim = path->msglim;
761         if (userdata)
762                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
763         parm->ctrl.ipflags1 = path->flags;
764
765         rc = iucv_call_b2f0(IUCV_ACCEPT, parm);
766         if (!rc) {
767                 path->private = private;
768                 path->msglim = parm->ctrl.ipmsglim;
769                 path->flags = parm->ctrl.ipflags1;
770         }
771         local_bh_enable();
772         return rc;
773 }
774 EXPORT_SYMBOL(iucv_path_accept);
775
776 /**
777  * iucv_path_connect
778  * @path: address of iucv path structure
779  * @handler: address of iucv handler structure
780  * @userid: 8-byte user identification
781  * @system: 8-byte target system identification
782  * @userdata: 16 bytes of data reflected to the communication partner
783  * @private: private data passed to interrupt handlers for this path
784  *
785  * This function establishes an IUCV path. Although the connect may complete
786  * successfully, you are not able to use the path until you receive an IUCV
787  * Connection Complete external interrupt.
788  *
789  * Returns the result of the CP IUCV call.
790  */
791 int iucv_path_connect(struct iucv_path *path, struct iucv_handler *handler,
792                       u8 userid[8], u8 system[8], u8 userdata[16],
793                       void *private)
794 {
795         union iucv_param *parm;
796         int rc;
797
798         BUG_ON(in_atomic());
799         spin_lock_bh(&iucv_table_lock);
800         iucv_cleanup_queue();
801         parm = percpu_ptr(iucv_param, smp_processor_id());
802         memset(parm, 0, sizeof(union iucv_param));
803         parm->ctrl.ipmsglim = path->msglim;
804         parm->ctrl.ipflags1 = path->flags;
805         if (userid) {
806                 memcpy(parm->ctrl.ipvmid, userid, sizeof(parm->ctrl.ipvmid));
807                 ASCEBC(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
808                 EBC_TOUPPER(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
809         }
810         if (system) {
811                 memcpy(parm->ctrl.iptarget, system,
812                        sizeof(parm->ctrl.iptarget));
813                 ASCEBC(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
814                 EBC_TOUPPER(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
815         }
816         if (userdata)
817                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
818
819         rc = iucv_call_b2f0(IUCV_CONNECT, parm);
820         if (!rc) {
821                 if (parm->ctrl.ippathid < iucv_max_pathid) {
822                         path->pathid = parm->ctrl.ippathid;
823                         path->msglim = parm->ctrl.ipmsglim;
824                         path->flags = parm->ctrl.ipflags1;
825                         path->handler = handler;
826                         path->private = private;
827                         list_add_tail(&path->list, &handler->paths);
828                         iucv_path_table[path->pathid] = path;
829                 } else {
830                         iucv_sever_pathid(parm->ctrl.ippathid,
831                                           iucv_error_pathid);
832                         rc = -EIO;
833                 }
834         }
835         spin_unlock_bh(&iucv_table_lock);
836         return rc;
837 }
838 EXPORT_SYMBOL(iucv_path_connect);
839
840 /**
841  * iucv_path_quiesce:
842  * @path: address of iucv path structure
843  * @userdata: 16 bytes of data reflected to the communication partner
844  *
845  * This function temporarily suspends incoming messages on an IUCV path.
846  * You can later reactivate the path by invoking the iucv_resume function.
847  *
848  * Returns the result from the CP IUCV call.
849  */
850 int iucv_path_quiesce(struct iucv_path *path, u8 userdata[16])
851 {
852         union iucv_param *parm;
853         int rc;
854
855         local_bh_disable();
856         parm = percpu_ptr(iucv_param, smp_processor_id());
857         memset(parm, 0, sizeof(union iucv_param));
858         if (userdata)
859                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
860         parm->ctrl.ippathid = path->pathid;
861         rc = iucv_call_b2f0(IUCV_QUIESCE, parm);
862         local_bh_enable();
863         return rc;
864 }
865 EXPORT_SYMBOL(iucv_path_quiesce);
866
867 /**
868  * iucv_path_resume:
869  * @path: address of iucv path structure
870  * @userdata: 16 bytes of data reflected to the communication partner
871  *
872  * This function resumes incoming messages on an IUCV path that has
873  * been stopped with iucv_path_quiesce.
874  *
875  * Returns the result from the CP IUCV call.
876  */
877 int iucv_path_resume(struct iucv_path *path, u8 userdata[16])
878 {
879         union iucv_param *parm;
880         int rc;
881
882         local_bh_disable();
883         parm = percpu_ptr(iucv_param, smp_processor_id());
884         memset(parm, 0, sizeof(union iucv_param));
885         if (userdata)
886                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
887         parm->ctrl.ippathid = path->pathid;
888         rc = iucv_call_b2f0(IUCV_RESUME, parm);
889         local_bh_enable();
890         return rc;
891 }
892
893 /**
894  * iucv_path_sever
895  * @path: address of iucv path structure
896  * @userdata: 16 bytes of data reflected to the communication partner
897  *
898  * This function terminates an IUCV path.
899  *
900  * Returns the result from the CP IUCV call.
901  */
902 int iucv_path_sever(struct iucv_path *path, u8 userdata[16])
903 {
904         int rc;
905
906         preempt_disable();
907         if (iucv_active_cpu != smp_processor_id())
908                 spin_lock_bh(&iucv_table_lock);
909         rc = iucv_sever_pathid(path->pathid, userdata);
910         if (!rc) {
911                 iucv_path_table[path->pathid] = NULL;
912                 list_del_init(&path->list);
913         }
914         if (iucv_active_cpu != smp_processor_id())
915                 spin_unlock_bh(&iucv_table_lock);
916         preempt_enable();
917         return rc;
918 }
919 EXPORT_SYMBOL(iucv_path_sever);
920
921 /**
922  * iucv_message_purge
923  * @path: address of iucv path structure
924  * @msg: address of iucv msg structure
925  * @srccls: source class of message
926  *
927  * Cancels a message you have sent.
928  *
929  * Returns the result from the CP IUCV call.
930  */
931 int iucv_message_purge(struct iucv_path *path, struct iucv_message *msg,
932                        u32 srccls)
933 {
934         union iucv_param *parm;
935         int rc;
936
937         local_bh_disable();
938         parm = percpu_ptr(iucv_param, smp_processor_id());
939         memset(parm, 0, sizeof(union iucv_param));
940         parm->purge.ippathid = path->pathid;
941         parm->purge.ipmsgid = msg->id;
942         parm->purge.ipsrccls = srccls;
943         parm->purge.ipflags1 = IUCV_IPSRCCLS | IUCV_IPFGMID | IUCV_IPFGPID;
944         rc = iucv_call_b2f0(IUCV_PURGE, parm);
945         if (!rc) {
946                 msg->audit = (*(u32 *) &parm->purge.ipaudit) >> 8;
947                 msg->tag = parm->purge.ipmsgtag;
948         }
949         local_bh_enable();
950         return rc;
951 }
952 EXPORT_SYMBOL(iucv_message_purge);
953
954 /**
955  * iucv_message_receive
956  * @path: address of iucv path structure
957  * @msg: address of iucv msg structure
958  * @flags: how the message is received (IUCV_IPBUFLST)
959  * @buffer: address of data buffer or address of struct iucv_array
960  * @size: length of data buffer
961  * @residual:
962  *
963  * This function receives messages that are being sent to you over
964  * established paths. This function will deal with RMDATA messages
965  * embedded in struct iucv_message as well.
966  *
967  * Returns the result from the CP IUCV call.
968  */
969 int iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
970                          u8 flags, void *buffer, size_t size, size_t *residual)
971 {
972         union iucv_param *parm;
973         struct iucv_array *array;
974         u8 *rmmsg;
975         size_t copy;
976         int rc;
977
978         if (msg->flags & IUCV_IPRMDATA) {
979                 /*
980                  * Message is 8 bytes long and has been stored to the
981                  * message descriptor itself.
982                  */
983                 rc = (size < 8) ? 5 : 0;
984                 if (residual)
985                         *residual = abs(size - 8);
986                 rmmsg = msg->rmmsg;
987                 if (flags & IUCV_IPBUFLST) {
988                         /* Copy to struct iucv_array. */
989                         size = (size < 8) ? size : 8;
990                         for (array = buffer; size > 0; array++) {
991                                 copy = min_t(size_t, size, array->length);
992                                 memcpy((u8 *)(addr_t) array->address,
993                                        rmmsg, copy);
994                                 rmmsg += copy;
995                                 size -= copy;
996                         }
997                 } else {
998                         /* Copy to direct buffer. */
999                         memcpy(buffer, rmmsg, min_t(size_t, size, 8));
1000                 }
1001                 return 0;
1002         }
1003
1004         local_bh_disable();
1005         parm = percpu_ptr(iucv_param, smp_processor_id());
1006         memset(parm, 0, sizeof(union iucv_param));
1007         parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1008         parm->db.ipbfln1f = (u32) size;
1009         parm->db.ipmsgid = msg->id;
1010         parm->db.ippathid = path->pathid;
1011         parm->db.iptrgcls = msg->class;
1012         parm->db.ipflags1 = (flags | IUCV_IPFGPID |
1013                              IUCV_IPFGMID | IUCV_IPTRGCLS);
1014         rc = iucv_call_b2f0(IUCV_RECEIVE, parm);
1015         if (!rc || rc == 5) {
1016                 msg->flags = parm->db.ipflags1;
1017                 if (residual)
1018                         *residual = parm->db.ipbfln1f;
1019         }
1020         local_bh_enable();
1021         return rc;
1022 }
1023 EXPORT_SYMBOL(iucv_message_receive);
1024
1025 /**
1026  * iucv_message_reject
1027  * @path: address of iucv path structure
1028  * @msg: address of iucv msg structure
1029  *
1030  * The reject function refuses a specified message. Between the time you
1031  * are notified of a message and the time that you complete the message,
1032  * the message may be rejected.
1033  *
1034  * Returns the result from the CP IUCV call.
1035  */
1036 int iucv_message_reject(struct iucv_path *path, struct iucv_message *msg)
1037 {
1038         union iucv_param *parm;
1039         int rc;
1040
1041         local_bh_disable();
1042         parm = percpu_ptr(iucv_param, smp_processor_id());
1043         memset(parm, 0, sizeof(union iucv_param));
1044         parm->db.ippathid = path->pathid;
1045         parm->db.ipmsgid = msg->id;
1046         parm->db.iptrgcls = msg->class;
1047         parm->db.ipflags1 = (IUCV_IPTRGCLS | IUCV_IPFGMID | IUCV_IPFGPID);
1048         rc = iucv_call_b2f0(IUCV_REJECT, parm);
1049         local_bh_enable();
1050         return rc;
1051 }
1052 EXPORT_SYMBOL(iucv_message_reject);
1053
1054 /**
1055  * iucv_message_reply
1056  * @path: address of iucv path structure
1057  * @msg: address of iucv msg structure
1058  * @flags: how the reply is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1059  * @reply: address of reply data buffer or address of struct iucv_array
1060  * @size: length of reply data buffer
1061  *
1062  * This function responds to the two-way messages that you receive. You
1063  * must identify completely the message to which you wish to reply. ie,
1064  * pathid, msgid, and trgcls. Prmmsg signifies the data is moved into
1065  * the parameter list.
1066  *
1067  * Returns the result from the CP IUCV call.
1068  */
1069 int iucv_message_reply(struct iucv_path *path, struct iucv_message *msg,
1070                        u8 flags, void *reply, size_t size)
1071 {
1072         union iucv_param *parm;
1073         int rc;
1074
1075         local_bh_disable();
1076         parm = percpu_ptr(iucv_param, smp_processor_id());
1077         memset(parm, 0, sizeof(union iucv_param));
1078         if (flags & IUCV_IPRMDATA) {
1079                 parm->dpl.ippathid = path->pathid;
1080                 parm->dpl.ipflags1 = flags;
1081                 parm->dpl.ipmsgid = msg->id;
1082                 parm->dpl.iptrgcls = msg->class;
1083                 memcpy(parm->dpl.iprmmsg, reply, min_t(size_t, size, 8));
1084         } else {
1085                 parm->db.ipbfadr1 = (u32)(addr_t) reply;
1086                 parm->db.ipbfln1f = (u32) size;
1087                 parm->db.ippathid = path->pathid;
1088                 parm->db.ipflags1 = flags;
1089                 parm->db.ipmsgid = msg->id;
1090                 parm->db.iptrgcls = msg->class;
1091         }
1092         rc = iucv_call_b2f0(IUCV_REPLY, parm);
1093         local_bh_enable();
1094         return rc;
1095 }
1096 EXPORT_SYMBOL(iucv_message_reply);
1097
1098 /**
1099  * iucv_message_send
1100  * @path: address of iucv path structure
1101  * @msg: address of iucv msg structure
1102  * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1103  * @srccls: source class of message
1104  * @buffer: address of send buffer or address of struct iucv_array
1105  * @size: length of send buffer
1106  *
1107  * This function transmits data to another application. Data to be
1108  * transmitted is in a buffer and this is a one-way message and the
1109  * receiver will not reply to the message.
1110  *
1111  * Returns the result from the CP IUCV call.
1112  */
1113 int iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
1114                       u8 flags, u32 srccls, void *buffer, size_t size)
1115 {
1116         union iucv_param *parm;
1117         int rc;
1118
1119         local_bh_disable();
1120         parm = percpu_ptr(iucv_param, smp_processor_id());
1121         memset(parm, 0, sizeof(union iucv_param));
1122         if (flags & IUCV_IPRMDATA) {
1123                 /* Message of 8 bytes can be placed into the parameter list. */
1124                 parm->dpl.ippathid = path->pathid;
1125                 parm->dpl.ipflags1 = flags | IUCV_IPNORPY;
1126                 parm->dpl.iptrgcls = msg->class;
1127                 parm->dpl.ipsrccls = srccls;
1128                 parm->dpl.ipmsgtag = msg->tag;
1129                 memcpy(parm->dpl.iprmmsg, buffer, 8);
1130         } else {
1131                 parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1132                 parm->db.ipbfln1f = (u32) size;
1133                 parm->db.ippathid = path->pathid;
1134                 parm->db.ipflags1 = flags | IUCV_IPNORPY;
1135                 parm->db.iptrgcls = msg->class;
1136                 parm->db.ipsrccls = srccls;
1137                 parm->db.ipmsgtag = msg->tag;
1138         }
1139         rc = iucv_call_b2f0(IUCV_SEND, parm);
1140         if (!rc)
1141                 msg->id = parm->db.ipmsgid;
1142         local_bh_enable();
1143         return rc;
1144 }
1145 EXPORT_SYMBOL(iucv_message_send);
1146
1147 /**
1148  * iucv_message_send2way
1149  * @path: address of iucv path structure
1150  * @msg: address of iucv msg structure
1151  * @flags: how the message is sent and the reply is received
1152  *         (IUCV_IPRMDATA, IUCV_IPBUFLST, IUCV_IPPRTY, IUCV_ANSLST)
1153  * @srccls: source class of message
1154  * @buffer: address of send buffer or address of struct iucv_array
1155  * @size: length of send buffer
1156  * @ansbuf: address of answer buffer or address of struct iucv_array
1157  * @asize: size of reply buffer
1158  *
1159  * This function transmits data to another application. Data to be
1160  * transmitted is in a buffer. The receiver of the send is expected to
1161  * reply to the message and a buffer is provided into which IUCV moves
1162  * the reply to this message.
1163  *
1164  * Returns the result from the CP IUCV call.
1165  */
1166 int iucv_message_send2way(struct iucv_path *path, struct iucv_message *msg,
1167                           u8 flags, u32 srccls, void *buffer, size_t size,
1168                           void *answer, size_t asize, size_t *residual)
1169 {
1170         union iucv_param *parm;
1171         int rc;
1172
1173         local_bh_disable();
1174         parm = percpu_ptr(iucv_param, smp_processor_id());
1175         memset(parm, 0, sizeof(union iucv_param));
1176         if (flags & IUCV_IPRMDATA) {
1177                 parm->dpl.ippathid = path->pathid;
1178                 parm->dpl.ipflags1 = path->flags;       /* priority message */
1179                 parm->dpl.iptrgcls = msg->class;
1180                 parm->dpl.ipsrccls = srccls;
1181                 parm->dpl.ipmsgtag = msg->tag;
1182                 parm->dpl.ipbfadr2 = (u32)(addr_t) answer;
1183                 parm->dpl.ipbfln2f = (u32) asize;
1184                 memcpy(parm->dpl.iprmmsg, buffer, 8);
1185         } else {
1186                 parm->db.ippathid = path->pathid;
1187                 parm->db.ipflags1 = path->flags;        /* priority message */
1188                 parm->db.iptrgcls = msg->class;
1189                 parm->db.ipsrccls = srccls;
1190                 parm->db.ipmsgtag = msg->tag;
1191                 parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1192                 parm->db.ipbfln1f = (u32) size;
1193                 parm->db.ipbfadr2 = (u32)(addr_t) answer;
1194                 parm->db.ipbfln2f = (u32) asize;
1195         }
1196         rc = iucv_call_b2f0(IUCV_SEND, parm);
1197         if (!rc)
1198                 msg->id = parm->db.ipmsgid;
1199         local_bh_enable();
1200         return rc;
1201 }
1202 EXPORT_SYMBOL(iucv_message_send2way);
1203
1204 /**
1205  * iucv_path_pending
1206  * @data: Pointer to external interrupt buffer
1207  *
1208  * Process connection pending work item. Called from tasklet while holding
1209  * iucv_table_lock.
1210  */
1211 struct iucv_path_pending {
1212         u16 ippathid;
1213         u8  ipflags1;
1214         u8  iptype;
1215         u16 ipmsglim;
1216         u16 res1;
1217         u8  ipvmid[8];
1218         u8  ipuser[16];
1219         u32 res3;
1220         u8  ippollfg;
1221         u8  res4[3];
1222 } __attribute__ ((packed));
1223
1224 static void iucv_path_pending(struct iucv_irq_data *data)
1225 {
1226         struct iucv_path_pending *ipp = (void *) data;
1227         struct iucv_handler *handler;
1228         struct iucv_path *path;
1229         char *error;
1230
1231         BUG_ON(iucv_path_table[ipp->ippathid]);
1232         /* New pathid, handler found. Create a new path struct. */
1233         error = iucv_error_no_memory;
1234         path = iucv_path_alloc(ipp->ipmsglim, ipp->ipflags1, GFP_ATOMIC);
1235         if (!path)
1236                 goto out_sever;
1237         path->pathid = ipp->ippathid;
1238         iucv_path_table[path->pathid] = path;
1239         EBCASC(ipp->ipvmid, 8);
1240
1241         /* Call registered handler until one is found that wants the path. */
1242         list_for_each_entry(handler, &iucv_handler_list, list) {
1243                 if (!handler->path_pending)
1244                         continue;
1245                 /*
1246                  * Add path to handler to allow a call to iucv_path_sever
1247                  * inside the path_pending function. If the handler returns
1248                  * an error remove the path from the handler again.
1249                  */
1250                 list_add(&path->list, &handler->paths);
1251                 path->handler = handler;
1252                 if (!handler->path_pending(path, ipp->ipvmid, ipp->ipuser))
1253                         return;
1254                 list_del(&path->list);
1255                 path->handler = NULL;
1256         }
1257         /* No handler wanted the path. */
1258         iucv_path_table[path->pathid] = NULL;
1259         iucv_path_free(path);
1260         error = iucv_error_no_listener;
1261 out_sever:
1262         iucv_sever_pathid(ipp->ippathid, error);
1263 }
1264
1265 /**
1266  * iucv_path_complete
1267  * @data: Pointer to external interrupt buffer
1268  *
1269  * Process connection complete work item. Called from tasklet while holding
1270  * iucv_table_lock.
1271  */
1272 struct iucv_path_complete {
1273         u16 ippathid;
1274         u8  ipflags1;
1275         u8  iptype;
1276         u16 ipmsglim;
1277         u16 res1;
1278         u8  res2[8];
1279         u8  ipuser[16];
1280         u32 res3;
1281         u8  ippollfg;
1282         u8  res4[3];
1283 } __attribute__ ((packed));
1284
1285 static void iucv_path_complete(struct iucv_irq_data *data)
1286 {
1287         struct iucv_path_complete *ipc = (void *) data;
1288         struct iucv_path *path = iucv_path_table[ipc->ippathid];
1289
1290         if (path && path->handler && path->handler->path_complete)
1291                 path->handler->path_complete(path, ipc->ipuser);
1292 }
1293
1294 /**
1295  * iucv_path_severed
1296  * @data: Pointer to external interrupt buffer
1297  *
1298  * Process connection severed work item. Called from tasklet while holding
1299  * iucv_table_lock.
1300  */
1301 struct iucv_path_severed {
1302         u16 ippathid;
1303         u8  res1;
1304         u8  iptype;
1305         u32 res2;
1306         u8  res3[8];
1307         u8  ipuser[16];
1308         u32 res4;
1309         u8  ippollfg;
1310         u8  res5[3];
1311 } __attribute__ ((packed));
1312
1313 static void iucv_path_severed(struct iucv_irq_data *data)
1314 {
1315         struct iucv_path_severed *ips = (void *) data;
1316         struct iucv_path *path = iucv_path_table[ips->ippathid];
1317
1318         if (!path || !path->handler)    /* Already severed */
1319                 return;
1320         if (path->handler->path_severed)
1321                 path->handler->path_severed(path, ips->ipuser);
1322         else {
1323                 iucv_sever_pathid(path->pathid, NULL);
1324                 iucv_path_table[path->pathid] = NULL;
1325                 list_del_init(&path->list);
1326                 iucv_path_free(path);
1327         }
1328 }
1329
1330 /**
1331  * iucv_path_quiesced
1332  * @data: Pointer to external interrupt buffer
1333  *
1334  * Process connection quiesced work item. Called from tasklet while holding
1335  * iucv_table_lock.
1336  */
1337 struct iucv_path_quiesced {
1338         u16 ippathid;
1339         u8  res1;
1340         u8  iptype;
1341         u32 res2;
1342         u8  res3[8];
1343         u8  ipuser[16];
1344         u32 res4;
1345         u8  ippollfg;
1346         u8  res5[3];
1347 } __attribute__ ((packed));
1348
1349 static void iucv_path_quiesced(struct iucv_irq_data *data)
1350 {
1351         struct iucv_path_quiesced *ipq = (void *) data;
1352         struct iucv_path *path = iucv_path_table[ipq->ippathid];
1353
1354         if (path && path->handler && path->handler->path_quiesced)
1355                 path->handler->path_quiesced(path, ipq->ipuser);
1356 }
1357
1358 /**
1359  * iucv_path_resumed
1360  * @data: Pointer to external interrupt buffer
1361  *
1362  * Process connection resumed work item. Called from tasklet while holding
1363  * iucv_table_lock.
1364  */
1365 struct iucv_path_resumed {
1366         u16 ippathid;
1367         u8  res1;
1368         u8  iptype;
1369         u32 res2;
1370         u8  res3[8];
1371         u8  ipuser[16];
1372         u32 res4;
1373         u8  ippollfg;
1374         u8  res5[3];
1375 } __attribute__ ((packed));
1376
1377 static void iucv_path_resumed(struct iucv_irq_data *data)
1378 {
1379         struct iucv_path_resumed *ipr = (void *) data;
1380         struct iucv_path *path = iucv_path_table[ipr->ippathid];
1381
1382         if (path && path->handler && path->handler->path_resumed)
1383                 path->handler->path_resumed(path, ipr->ipuser);
1384 }
1385
1386 /**
1387  * iucv_message_complete
1388  * @data: Pointer to external interrupt buffer
1389  *
1390  * Process message complete work item. Called from tasklet while holding
1391  * iucv_table_lock.
1392  */
1393 struct iucv_message_complete {
1394         u16 ippathid;
1395         u8  ipflags1;
1396         u8  iptype;
1397         u32 ipmsgid;
1398         u32 ipaudit;
1399         u8  iprmmsg[8];
1400         u32 ipsrccls;
1401         u32 ipmsgtag;
1402         u32 res;
1403         u32 ipbfln2f;
1404         u8  ippollfg;
1405         u8  res2[3];
1406 } __attribute__ ((packed));
1407
1408 static void iucv_message_complete(struct iucv_irq_data *data)
1409 {
1410         struct iucv_message_complete *imc = (void *) data;
1411         struct iucv_path *path = iucv_path_table[imc->ippathid];
1412         struct iucv_message msg;
1413
1414         if (path && path->handler && path->handler->message_complete) {
1415                 msg.flags = imc->ipflags1;
1416                 msg.id = imc->ipmsgid;
1417                 msg.audit = imc->ipaudit;
1418                 memcpy(msg.rmmsg, imc->iprmmsg, 8);
1419                 msg.class = imc->ipsrccls;
1420                 msg.tag = imc->ipmsgtag;
1421                 msg.length = imc->ipbfln2f;
1422                 path->handler->message_complete(path, &msg);
1423         }
1424 }
1425
1426 /**
1427  * iucv_message_pending
1428  * @data: Pointer to external interrupt buffer
1429  *
1430  * Process message pending work item. Called from tasklet while holding
1431  * iucv_table_lock.
1432  */
1433 struct iucv_message_pending {
1434         u16 ippathid;
1435         u8  ipflags1;
1436         u8  iptype;
1437         u32 ipmsgid;
1438         u32 iptrgcls;
1439         union {
1440                 u32 iprmmsg1_u32;
1441                 u8  iprmmsg1[4];
1442         } ln1msg1;
1443         union {
1444                 u32 ipbfln1f;
1445                 u8  iprmmsg2[4];
1446         } ln1msg2;
1447         u32 res1[3];
1448         u32 ipbfln2f;
1449         u8  ippollfg;
1450         u8  res2[3];
1451 } __attribute__ ((packed));
1452
1453 static void iucv_message_pending(struct iucv_irq_data *data)
1454 {
1455         struct iucv_message_pending *imp = (void *) data;
1456         struct iucv_path *path = iucv_path_table[imp->ippathid];
1457         struct iucv_message msg;
1458
1459         if (path && path->handler && path->handler->message_pending) {
1460                 msg.flags = imp->ipflags1;
1461                 msg.id = imp->ipmsgid;
1462                 msg.class = imp->iptrgcls;
1463                 if (imp->ipflags1 & IUCV_IPRMDATA) {
1464                         memcpy(msg.rmmsg, imp->ln1msg1.iprmmsg1, 8);
1465                         msg.length = 8;
1466                 } else
1467                         msg.length = imp->ln1msg2.ipbfln1f;
1468                 msg.reply_size = imp->ipbfln2f;
1469                 path->handler->message_pending(path, &msg);
1470         }
1471 }
1472
1473 /**
1474  * iucv_tasklet_fn:
1475  *
1476  * This tasklet loops over the queue of irq buffers created by
1477  * iucv_external_interrupt, calls the appropriate action handler
1478  * and then frees the buffer.
1479  */
1480 static void iucv_tasklet_fn(unsigned long ignored)
1481 {
1482         typedef void iucv_irq_fn(struct iucv_irq_data *);
1483         static iucv_irq_fn *irq_fn[] = {
1484                 [0x02] = iucv_path_complete,
1485                 [0x03] = iucv_path_severed,
1486                 [0x04] = iucv_path_quiesced,
1487                 [0x05] = iucv_path_resumed,
1488                 [0x06] = iucv_message_complete,
1489                 [0x07] = iucv_message_complete,
1490                 [0x08] = iucv_message_pending,
1491                 [0x09] = iucv_message_pending,
1492         };
1493         struct list_head task_queue = LIST_HEAD_INIT(task_queue);
1494         struct iucv_irq_list *p, *n;
1495
1496         /* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1497         if (!spin_trylock(&iucv_table_lock)) {
1498                 tasklet_schedule(&iucv_tasklet);
1499                 return;
1500         }
1501         iucv_active_cpu = smp_processor_id();
1502
1503         spin_lock_irq(&iucv_queue_lock);
1504         list_splice_init(&iucv_task_queue, &task_queue);
1505         spin_unlock_irq(&iucv_queue_lock);
1506
1507         list_for_each_entry_safe(p, n, &task_queue, list) {
1508                 list_del_init(&p->list);
1509                 irq_fn[p->data.iptype](&p->data);
1510                 kfree(p);
1511         }
1512
1513         iucv_active_cpu = -1;
1514         spin_unlock(&iucv_table_lock);
1515 }
1516
1517 /**
1518  * iucv_work_fn:
1519  *
1520  * This work function loops over the queue of path pending irq blocks
1521  * created by iucv_external_interrupt, calls the appropriate action
1522  * handler and then frees the buffer.
1523  */
1524 static void iucv_work_fn(struct work_struct *work)
1525 {
1526         typedef void iucv_irq_fn(struct iucv_irq_data *);
1527         struct list_head work_queue = LIST_HEAD_INIT(work_queue);
1528         struct iucv_irq_list *p, *n;
1529
1530         /* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1531         spin_lock_bh(&iucv_table_lock);
1532         iucv_active_cpu = smp_processor_id();
1533
1534         spin_lock_irq(&iucv_queue_lock);
1535         list_splice_init(&iucv_work_queue, &work_queue);
1536         spin_unlock_irq(&iucv_queue_lock);
1537
1538         iucv_cleanup_queue();
1539         list_for_each_entry_safe(p, n, &work_queue, list) {
1540                 list_del_init(&p->list);
1541                 iucv_path_pending(&p->data);
1542                 kfree(p);
1543         }
1544
1545         iucv_active_cpu = -1;
1546         spin_unlock_bh(&iucv_table_lock);
1547 }
1548
1549 /**
1550  * iucv_external_interrupt
1551  * @code: irq code
1552  *
1553  * Handles external interrupts coming in from CP.
1554  * Places the interrupt buffer on a queue and schedules iucv_tasklet_fn().
1555  */
1556 static void iucv_external_interrupt(u16 code)
1557 {
1558         struct iucv_irq_data *p;
1559         struct iucv_irq_list *work;
1560
1561         p = percpu_ptr(iucv_irq_data, smp_processor_id());
1562         if (p->ippathid >= iucv_max_pathid) {
1563                 printk(KERN_WARNING "iucv_do_int: Got interrupt with "
1564                        "pathid %d > max_connections (%ld)\n",
1565                        p->ippathid, iucv_max_pathid - 1);
1566                 iucv_sever_pathid(p->ippathid, iucv_error_no_listener);
1567                 return;
1568         }
1569         if (p->iptype  < 0x01 || p->iptype > 0x09) {
1570                 printk(KERN_ERR "iucv_do_int: unknown iucv interrupt\n");
1571                 return;
1572         }
1573         work = kmalloc(sizeof(struct iucv_irq_list), GFP_ATOMIC);
1574         if (!work) {
1575                 printk(KERN_WARNING "iucv_external_interrupt: out of memory\n");
1576                 return;
1577         }
1578         memcpy(&work->data, p, sizeof(work->data));
1579         spin_lock(&iucv_queue_lock);
1580         if (p->iptype == 0x01) {
1581                 /* Path pending interrupt. */
1582                 list_add_tail(&work->list, &iucv_work_queue);
1583                 schedule_work(&iucv_work);
1584         } else {
1585                 /* The other interrupts. */
1586                 list_add_tail(&work->list, &iucv_task_queue);
1587                 tasklet_schedule(&iucv_tasklet);
1588         }
1589         spin_unlock(&iucv_queue_lock);
1590 }
1591
1592 /**
1593  * iucv_init
1594  *
1595  * Allocates and initializes various data structures.
1596  */
1597 static int __init iucv_init(void)
1598 {
1599         int rc;
1600
1601         if (!MACHINE_IS_VM) {
1602                 rc = -EPROTONOSUPPORT;
1603                 goto out;
1604         }
1605         rc = iucv_query_maxconn();
1606         if (rc)
1607                 goto out;
1608         rc = register_external_interrupt(0x4000, iucv_external_interrupt);
1609         if (rc)
1610                 goto out;
1611         rc = bus_register(&iucv_bus);
1612         if (rc)
1613                 goto out_int;
1614         iucv_root = s390_root_dev_register("iucv");
1615         if (IS_ERR(iucv_root)) {
1616                 rc = PTR_ERR(iucv_root);
1617                 goto out_bus;
1618         }
1619         /* Note: GFP_DMA used to get memory below 2G */
1620         iucv_irq_data = percpu_alloc(sizeof(struct iucv_irq_data),
1621                                      GFP_KERNEL|GFP_DMA);
1622         if (!iucv_irq_data) {
1623                 rc = -ENOMEM;
1624                 goto out_root;
1625         }
1626         /* Allocate parameter blocks. */
1627         iucv_param = percpu_alloc(sizeof(union iucv_param),
1628                                   GFP_KERNEL|GFP_DMA);
1629         if (!iucv_param) {
1630                 rc = -ENOMEM;
1631                 goto out_extint;
1632         }
1633         register_hotcpu_notifier(&iucv_cpu_notifier);
1634         ASCEBC(iucv_error_no_listener, 16);
1635         ASCEBC(iucv_error_no_memory, 16);
1636         ASCEBC(iucv_error_pathid, 16);
1637         iucv_available = 1;
1638         return 0;
1639
1640 out_extint:
1641         percpu_free(iucv_irq_data);
1642 out_root:
1643         s390_root_dev_unregister(iucv_root);
1644 out_bus:
1645         bus_unregister(&iucv_bus);
1646 out_int:
1647         unregister_external_interrupt(0x4000, iucv_external_interrupt);
1648 out:
1649         return rc;
1650 }
1651
1652 /**
1653  * iucv_exit
1654  *
1655  * Frees everything allocated from iucv_init.
1656  */
1657 static void __exit iucv_exit(void)
1658 {
1659         struct iucv_irq_list *p, *n;
1660
1661         spin_lock_irq(&iucv_queue_lock);
1662         list_for_each_entry_safe(p, n, &iucv_task_queue, list)
1663                 kfree(p);
1664         list_for_each_entry_safe(p, n, &iucv_work_queue, list)
1665                 kfree(p);
1666         spin_unlock_irq(&iucv_queue_lock);
1667         unregister_hotcpu_notifier(&iucv_cpu_notifier);
1668         percpu_free(iucv_param);
1669         percpu_free(iucv_irq_data);
1670         s390_root_dev_unregister(iucv_root);
1671         bus_unregister(&iucv_bus);
1672         unregister_external_interrupt(0x4000, iucv_external_interrupt);
1673 }
1674
1675 subsys_initcall(iucv_init);
1676 module_exit(iucv_exit);
1677
1678 MODULE_AUTHOR("(C) 2001 IBM Corp. by Fritz Elfert (felfert@millenux.com)");
1679 MODULE_DESCRIPTION("Linux for S/390 IUCV lowlevel driver");
1680 MODULE_LICENSE("GPL");