983058d432dc8c613f63a48af80db1997679dd3f
[linux-2.6.git] / 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_single(cpu, iucv_allow_cpu,
483                                                  NULL, 0, 1);
484         preempt_enable();
485 }
486
487 /**
488  * iucv_setmask_up
489  *
490  * Allow iucv interrupts on a single cpu.
491  */
492 static void iucv_setmask_up(void)
493 {
494         cpumask_t cpumask;
495         int cpu;
496
497         /* Disable all cpu but the first in cpu_irq_cpumask. */
498         cpumask = iucv_irq_cpumask;
499         cpu_clear(first_cpu(iucv_irq_cpumask), cpumask);
500         for_each_cpu_mask(cpu, cpumask)
501                 smp_call_function_single(cpu, iucv_block_cpu, NULL, 0, 1);
502 }
503
504 /**
505  * iucv_enable
506  *
507  * This function makes iucv ready for use. It allocates the pathid
508  * table, declares an iucv interrupt buffer and enables the iucv
509  * interrupts. Called when the first user has registered an iucv
510  * handler.
511  */
512 static int iucv_enable(void)
513 {
514         size_t alloc_size;
515         int cpu, rc;
516
517         rc = -ENOMEM;
518         alloc_size = iucv_max_pathid * sizeof(struct iucv_path);
519         iucv_path_table = kzalloc(alloc_size, GFP_KERNEL);
520         if (!iucv_path_table)
521                 goto out;
522         /* Declare per cpu buffers. */
523         rc = -EIO;
524         preempt_disable();
525         for_each_online_cpu(cpu)
526                 smp_call_function_single(cpu, iucv_declare_cpu, NULL, 0, 1);
527         preempt_enable();
528         if (cpus_empty(iucv_buffer_cpumask))
529                 /* No cpu could declare an iucv buffer. */
530                 goto out_path;
531         return 0;
532
533 out_path:
534         kfree(iucv_path_table);
535 out:
536         return rc;
537 }
538
539 /**
540  * iucv_disable
541  *
542  * This function shuts down iucv. It disables iucv interrupts, retrieves
543  * the iucv interrupt buffer and frees the pathid table. Called after the
544  * last user unregister its iucv handler.
545  */
546 static void iucv_disable(void)
547 {
548         on_each_cpu(iucv_retrieve_cpu, NULL, 0, 1);
549         kfree(iucv_path_table);
550 }
551
552 static int __cpuinit iucv_cpu_notify(struct notifier_block *self,
553                                      unsigned long action, void *hcpu)
554 {
555         cpumask_t cpumask;
556         long cpu = (long) hcpu;
557
558         switch (action) {
559         case CPU_UP_PREPARE:
560         case CPU_UP_PREPARE_FROZEN:
561                 if (!percpu_populate(iucv_irq_data,
562                                      sizeof(struct iucv_irq_data),
563                                      GFP_KERNEL|GFP_DMA, cpu))
564                         return NOTIFY_BAD;
565                 if (!percpu_populate(iucv_param, sizeof(union iucv_param),
566                                      GFP_KERNEL|GFP_DMA, cpu)) {
567                         percpu_depopulate(iucv_irq_data, cpu);
568                         return NOTIFY_BAD;
569                 }
570                 break;
571         case CPU_UP_CANCELED:
572         case CPU_UP_CANCELED_FROZEN:
573         case CPU_DEAD:
574         case CPU_DEAD_FROZEN:
575                 percpu_depopulate(iucv_param, cpu);
576                 percpu_depopulate(iucv_irq_data, cpu);
577                 break;
578         case CPU_ONLINE:
579         case CPU_ONLINE_FROZEN:
580         case CPU_DOWN_FAILED:
581         case CPU_DOWN_FAILED_FROZEN:
582                 smp_call_function_single(cpu, iucv_declare_cpu, NULL, 0, 1);
583                 break;
584         case CPU_DOWN_PREPARE:
585         case CPU_DOWN_PREPARE_FROZEN:
586                 cpumask = iucv_buffer_cpumask;
587                 cpu_clear(cpu, cpumask);
588                 if (cpus_empty(cpumask))
589                         /* Can't offline last IUCV enabled cpu. */
590                         return NOTIFY_BAD;
591                 smp_call_function_single(cpu, iucv_retrieve_cpu, NULL, 0, 1);
592                 if (cpus_empty(iucv_irq_cpumask))
593                         smp_call_function_single(first_cpu(iucv_buffer_cpumask),
594                                                  iucv_allow_cpu, NULL, 0, 1);
595                 break;
596         }
597         return NOTIFY_OK;
598 }
599
600 static struct notifier_block __cpuinitdata iucv_cpu_notifier = {
601         .notifier_call = iucv_cpu_notify,
602 };
603
604 /**
605  * iucv_sever_pathid
606  * @pathid: path identification number.
607  * @userdata: 16-bytes of user data.
608  *
609  * Sever an iucv path to free up the pathid. Used internally.
610  */
611 static int iucv_sever_pathid(u16 pathid, u8 userdata[16])
612 {
613         union iucv_param *parm;
614
615         parm = percpu_ptr(iucv_param, smp_processor_id());
616         memset(parm, 0, sizeof(union iucv_param));
617         if (userdata)
618                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
619         parm->ctrl.ippathid = pathid;
620         return iucv_call_b2f0(IUCV_SEVER, parm);
621 }
622
623 #ifdef CONFIG_SMP
624 /**
625  * __iucv_cleanup_queue
626  * @dummy: unused dummy argument
627  *
628  * Nop function called via smp_call_function to force work items from
629  * pending external iucv interrupts to the work queue.
630  */
631 static void __iucv_cleanup_queue(void *dummy)
632 {
633 }
634 #endif
635
636 /**
637  * iucv_cleanup_queue
638  *
639  * Function called after a path has been severed to find all remaining
640  * work items for the now stale pathid. The caller needs to hold the
641  * iucv_table_lock.
642  */
643 static void iucv_cleanup_queue(void)
644 {
645         struct iucv_irq_list *p, *n;
646
647         /*
648          * When a path is severed, the pathid can be reused immediatly
649          * on a iucv connect or a connection pending interrupt. Remove
650          * all entries from the task queue that refer to a stale pathid
651          * (iucv_path_table[ix] == NULL). Only then do the iucv connect
652          * or deliver the connection pending interrupt. To get all the
653          * pending interrupts force them to the work queue by calling
654          * an empty function on all cpus.
655          */
656         smp_call_function(__iucv_cleanup_queue, NULL, 0, 1);
657         spin_lock_irq(&iucv_queue_lock);
658         list_for_each_entry_safe(p, n, &iucv_task_queue, list) {
659                 /* Remove stale work items from the task queue. */
660                 if (iucv_path_table[p->data.ippathid] == NULL) {
661                         list_del(&p->list);
662                         kfree(p);
663                 }
664         }
665         spin_unlock_irq(&iucv_queue_lock);
666 }
667
668 /**
669  * iucv_register:
670  * @handler: address of iucv handler structure
671  * @smp: != 0 indicates that the handler can deal with out of order messages
672  *
673  * Registers a driver with IUCV.
674  *
675  * Returns 0 on success, -ENOMEM if the memory allocation for the pathid
676  * table failed, or -EIO if IUCV_DECLARE_BUFFER failed on all cpus.
677  */
678 int iucv_register(struct iucv_handler *handler, int smp)
679 {
680         int rc;
681
682         if (!iucv_available)
683                 return -ENOSYS;
684         mutex_lock(&iucv_register_mutex);
685         if (!smp)
686                 iucv_nonsmp_handler++;
687         if (list_empty(&iucv_handler_list)) {
688                 rc = iucv_enable();
689                 if (rc)
690                         goto out_mutex;
691         } else if (!smp && iucv_nonsmp_handler == 1)
692                 iucv_setmask_up();
693         INIT_LIST_HEAD(&handler->paths);
694
695         spin_lock_irq(&iucv_table_lock);
696         list_add_tail(&handler->list, &iucv_handler_list);
697         spin_unlock_irq(&iucv_table_lock);
698         rc = 0;
699 out_mutex:
700         mutex_unlock(&iucv_register_mutex);
701         return rc;
702 }
703 EXPORT_SYMBOL(iucv_register);
704
705 /**
706  * iucv_unregister
707  * @handler:  address of iucv handler structure
708  * @smp: != 0 indicates that the handler can deal with out of order messages
709  *
710  * Unregister driver from IUCV.
711  */
712 void iucv_unregister(struct iucv_handler *handler, int smp)
713 {
714         struct iucv_path *p, *n;
715
716         mutex_lock(&iucv_register_mutex);
717         spin_lock_bh(&iucv_table_lock);
718         /* Remove handler from the iucv_handler_list. */
719         list_del_init(&handler->list);
720         /* Sever all pathids still refering to the handler. */
721         list_for_each_entry_safe(p, n, &handler->paths, list) {
722                 iucv_sever_pathid(p->pathid, NULL);
723                 iucv_path_table[p->pathid] = NULL;
724                 list_del(&p->list);
725                 iucv_path_free(p);
726         }
727         spin_unlock_bh(&iucv_table_lock);
728         if (!smp)
729                 iucv_nonsmp_handler--;
730         if (list_empty(&iucv_handler_list))
731                 iucv_disable();
732         else if (!smp && iucv_nonsmp_handler == 0)
733                 iucv_setmask_mp();
734         mutex_unlock(&iucv_register_mutex);
735 }
736 EXPORT_SYMBOL(iucv_unregister);
737
738 /**
739  * iucv_path_accept
740  * @path: address of iucv path structure
741  * @handler: address of iucv handler structure
742  * @userdata: 16 bytes of data reflected to the communication partner
743  * @private: private data passed to interrupt handlers for this path
744  *
745  * This function is issued after the user received a connection pending
746  * external interrupt and now wishes to complete the IUCV communication path.
747  *
748  * Returns the result of the CP IUCV call.
749  */
750 int iucv_path_accept(struct iucv_path *path, struct iucv_handler *handler,
751                      u8 userdata[16], void *private)
752 {
753         union iucv_param *parm;
754         int rc;
755
756         local_bh_disable();
757         /* Prepare parameter block. */
758         parm = percpu_ptr(iucv_param, smp_processor_id());
759         memset(parm, 0, sizeof(union iucv_param));
760         parm->ctrl.ippathid = path->pathid;
761         parm->ctrl.ipmsglim = path->msglim;
762         if (userdata)
763                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
764         parm->ctrl.ipflags1 = path->flags;
765
766         rc = iucv_call_b2f0(IUCV_ACCEPT, parm);
767         if (!rc) {
768                 path->private = private;
769                 path->msglim = parm->ctrl.ipmsglim;
770                 path->flags = parm->ctrl.ipflags1;
771         }
772         local_bh_enable();
773         return rc;
774 }
775 EXPORT_SYMBOL(iucv_path_accept);
776
777 /**
778  * iucv_path_connect
779  * @path: address of iucv path structure
780  * @handler: address of iucv handler structure
781  * @userid: 8-byte user identification
782  * @system: 8-byte target system identification
783  * @userdata: 16 bytes of data reflected to the communication partner
784  * @private: private data passed to interrupt handlers for this path
785  *
786  * This function establishes an IUCV path. Although the connect may complete
787  * successfully, you are not able to use the path until you receive an IUCV
788  * Connection Complete external interrupt.
789  *
790  * Returns the result of the CP IUCV call.
791  */
792 int iucv_path_connect(struct iucv_path *path, struct iucv_handler *handler,
793                       u8 userid[8], u8 system[8], u8 userdata[16],
794                       void *private)
795 {
796         union iucv_param *parm;
797         int rc;
798
799         BUG_ON(in_atomic());
800         spin_lock_bh(&iucv_table_lock);
801         iucv_cleanup_queue();
802         parm = percpu_ptr(iucv_param, smp_processor_id());
803         memset(parm, 0, sizeof(union iucv_param));
804         parm->ctrl.ipmsglim = path->msglim;
805         parm->ctrl.ipflags1 = path->flags;
806         if (userid) {
807                 memcpy(parm->ctrl.ipvmid, userid, sizeof(parm->ctrl.ipvmid));
808                 ASCEBC(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
809                 EBC_TOUPPER(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
810         }
811         if (system) {
812                 memcpy(parm->ctrl.iptarget, system,
813                        sizeof(parm->ctrl.iptarget));
814                 ASCEBC(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
815                 EBC_TOUPPER(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
816         }
817         if (userdata)
818                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
819
820         rc = iucv_call_b2f0(IUCV_CONNECT, parm);
821         if (!rc) {
822                 if (parm->ctrl.ippathid < iucv_max_pathid) {
823                         path->pathid = parm->ctrl.ippathid;
824                         path->msglim = parm->ctrl.ipmsglim;
825                         path->flags = parm->ctrl.ipflags1;
826                         path->handler = handler;
827                         path->private = private;
828                         list_add_tail(&path->list, &handler->paths);
829                         iucv_path_table[path->pathid] = path;
830                 } else {
831                         iucv_sever_pathid(parm->ctrl.ippathid,
832                                           iucv_error_pathid);
833                         rc = -EIO;
834                 }
835         }
836         spin_unlock_bh(&iucv_table_lock);
837         return rc;
838 }
839 EXPORT_SYMBOL(iucv_path_connect);
840
841 /**
842  * iucv_path_quiesce:
843  * @path: address of iucv path structure
844  * @userdata: 16 bytes of data reflected to the communication partner
845  *
846  * This function temporarily suspends incoming messages on an IUCV path.
847  * You can later reactivate the path by invoking the iucv_resume function.
848  *
849  * Returns the result from the CP IUCV call.
850  */
851 int iucv_path_quiesce(struct iucv_path *path, u8 userdata[16])
852 {
853         union iucv_param *parm;
854         int rc;
855
856         local_bh_disable();
857         parm = percpu_ptr(iucv_param, smp_processor_id());
858         memset(parm, 0, sizeof(union iucv_param));
859         if (userdata)
860                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
861         parm->ctrl.ippathid = path->pathid;
862         rc = iucv_call_b2f0(IUCV_QUIESCE, parm);
863         local_bh_enable();
864         return rc;
865 }
866 EXPORT_SYMBOL(iucv_path_quiesce);
867
868 /**
869  * iucv_path_resume:
870  * @path: address of iucv path structure
871  * @userdata: 16 bytes of data reflected to the communication partner
872  *
873  * This function resumes incoming messages on an IUCV path that has
874  * been stopped with iucv_path_quiesce.
875  *
876  * Returns the result from the CP IUCV call.
877  */
878 int iucv_path_resume(struct iucv_path *path, u8 userdata[16])
879 {
880         union iucv_param *parm;
881         int rc;
882
883         local_bh_disable();
884         parm = percpu_ptr(iucv_param, smp_processor_id());
885         memset(parm, 0, sizeof(union iucv_param));
886         if (userdata)
887                 memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
888         parm->ctrl.ippathid = path->pathid;
889         rc = iucv_call_b2f0(IUCV_RESUME, parm);
890         local_bh_enable();
891         return rc;
892 }
893
894 /**
895  * iucv_path_sever
896  * @path: address of iucv path structure
897  * @userdata: 16 bytes of data reflected to the communication partner
898  *
899  * This function terminates an IUCV path.
900  *
901  * Returns the result from the CP IUCV call.
902  */
903 int iucv_path_sever(struct iucv_path *path, u8 userdata[16])
904 {
905         int rc;
906
907         preempt_disable();
908         if (iucv_active_cpu != smp_processor_id())
909                 spin_lock_bh(&iucv_table_lock);
910         rc = iucv_sever_pathid(path->pathid, userdata);
911         if (!rc) {
912                 iucv_path_table[path->pathid] = NULL;
913                 list_del_init(&path->list);
914         }
915         if (iucv_active_cpu != smp_processor_id())
916                 spin_unlock_bh(&iucv_table_lock);
917         preempt_enable();
918         return rc;
919 }
920 EXPORT_SYMBOL(iucv_path_sever);
921
922 /**
923  * iucv_message_purge
924  * @path: address of iucv path structure
925  * @msg: address of iucv msg structure
926  * @srccls: source class of message
927  *
928  * Cancels a message you have sent.
929  *
930  * Returns the result from the CP IUCV call.
931  */
932 int iucv_message_purge(struct iucv_path *path, struct iucv_message *msg,
933                        u32 srccls)
934 {
935         union iucv_param *parm;
936         int rc;
937
938         local_bh_disable();
939         parm = percpu_ptr(iucv_param, smp_processor_id());
940         memset(parm, 0, sizeof(union iucv_param));
941         parm->purge.ippathid = path->pathid;
942         parm->purge.ipmsgid = msg->id;
943         parm->purge.ipsrccls = srccls;
944         parm->purge.ipflags1 = IUCV_IPSRCCLS | IUCV_IPFGMID | IUCV_IPFGPID;
945         rc = iucv_call_b2f0(IUCV_PURGE, parm);
946         if (!rc) {
947                 msg->audit = (*(u32 *) &parm->purge.ipaudit) >> 8;
948                 msg->tag = parm->purge.ipmsgtag;
949         }
950         local_bh_enable();
951         return rc;
952 }
953 EXPORT_SYMBOL(iucv_message_purge);
954
955 /**
956  * iucv_message_receive
957  * @path: address of iucv path structure
958  * @msg: address of iucv msg structure
959  * @flags: how the message is received (IUCV_IPBUFLST)
960  * @buffer: address of data buffer or address of struct iucv_array
961  * @size: length of data buffer
962  * @residual:
963  *
964  * This function receives messages that are being sent to you over
965  * established paths. This function will deal with RMDATA messages
966  * embedded in struct iucv_message as well.
967  *
968  * Returns the result from the CP IUCV call.
969  */
970 int iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
971                          u8 flags, void *buffer, size_t size, size_t *residual)
972 {
973         union iucv_param *parm;
974         struct iucv_array *array;
975         u8 *rmmsg;
976         size_t copy;
977         int rc;
978
979         if (msg->flags & IUCV_IPRMDATA) {
980                 /*
981                  * Message is 8 bytes long and has been stored to the
982                  * message descriptor itself.
983                  */
984                 rc = (size < 8) ? 5 : 0;
985                 if (residual)
986                         *residual = abs(size - 8);
987                 rmmsg = msg->rmmsg;
988                 if (flags & IUCV_IPBUFLST) {
989                         /* Copy to struct iucv_array. */
990                         size = (size < 8) ? size : 8;
991                         for (array = buffer; size > 0; array++) {
992                                 copy = min_t(size_t, size, array->length);
993                                 memcpy((u8 *)(addr_t) array->address,
994                                        rmmsg, copy);
995                                 rmmsg += copy;
996                                 size -= copy;
997                         }
998                 } else {
999                         /* Copy to direct buffer. */
1000                         memcpy(buffer, rmmsg, min_t(size_t, size, 8));
1001                 }
1002                 return 0;
1003         }
1004
1005         local_bh_disable();
1006         parm = percpu_ptr(iucv_param, smp_processor_id());
1007         memset(parm, 0, sizeof(union iucv_param));
1008         parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1009         parm->db.ipbfln1f = (u32) size;
1010         parm->db.ipmsgid = msg->id;
1011         parm->db.ippathid = path->pathid;
1012         parm->db.iptrgcls = msg->class;
1013         parm->db.ipflags1 = (flags | IUCV_IPFGPID |
1014                              IUCV_IPFGMID | IUCV_IPTRGCLS);
1015         rc = iucv_call_b2f0(IUCV_RECEIVE, parm);
1016         if (!rc || rc == 5) {
1017                 msg->flags = parm->db.ipflags1;
1018                 if (residual)
1019                         *residual = parm->db.ipbfln1f;
1020         }
1021         local_bh_enable();
1022         return rc;
1023 }
1024 EXPORT_SYMBOL(iucv_message_receive);
1025
1026 /**
1027  * iucv_message_reject
1028  * @path: address of iucv path structure
1029  * @msg: address of iucv msg structure
1030  *
1031  * The reject function refuses a specified message. Between the time you
1032  * are notified of a message and the time that you complete the message,
1033  * the message may be rejected.
1034  *
1035  * Returns the result from the CP IUCV call.
1036  */
1037 int iucv_message_reject(struct iucv_path *path, struct iucv_message *msg)
1038 {
1039         union iucv_param *parm;
1040         int rc;
1041
1042         local_bh_disable();
1043         parm = percpu_ptr(iucv_param, smp_processor_id());
1044         memset(parm, 0, sizeof(union iucv_param));
1045         parm->db.ippathid = path->pathid;
1046         parm->db.ipmsgid = msg->id;
1047         parm->db.iptrgcls = msg->class;
1048         parm->db.ipflags1 = (IUCV_IPTRGCLS | IUCV_IPFGMID | IUCV_IPFGPID);
1049         rc = iucv_call_b2f0(IUCV_REJECT, parm);
1050         local_bh_enable();
1051         return rc;
1052 }
1053 EXPORT_SYMBOL(iucv_message_reject);
1054
1055 /**
1056  * iucv_message_reply
1057  * @path: address of iucv path structure
1058  * @msg: address of iucv msg structure
1059  * @flags: how the reply is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1060  * @reply: address of reply data buffer or address of struct iucv_array
1061  * @size: length of reply data buffer
1062  *
1063  * This function responds to the two-way messages that you receive. You
1064  * must identify completely the message to which you wish to reply. ie,
1065  * pathid, msgid, and trgcls. Prmmsg signifies the data is moved into
1066  * the parameter list.
1067  *
1068  * Returns the result from the CP IUCV call.
1069  */
1070 int iucv_message_reply(struct iucv_path *path, struct iucv_message *msg,
1071                        u8 flags, void *reply, size_t size)
1072 {
1073         union iucv_param *parm;
1074         int rc;
1075
1076         local_bh_disable();
1077         parm = percpu_ptr(iucv_param, smp_processor_id());
1078         memset(parm, 0, sizeof(union iucv_param));
1079         if (flags & IUCV_IPRMDATA) {
1080                 parm->dpl.ippathid = path->pathid;
1081                 parm->dpl.ipflags1 = flags;
1082                 parm->dpl.ipmsgid = msg->id;
1083                 parm->dpl.iptrgcls = msg->class;
1084                 memcpy(parm->dpl.iprmmsg, reply, min_t(size_t, size, 8));
1085         } else {
1086                 parm->db.ipbfadr1 = (u32)(addr_t) reply;
1087                 parm->db.ipbfln1f = (u32) size;
1088                 parm->db.ippathid = path->pathid;
1089                 parm->db.ipflags1 = flags;
1090                 parm->db.ipmsgid = msg->id;
1091                 parm->db.iptrgcls = msg->class;
1092         }
1093         rc = iucv_call_b2f0(IUCV_REPLY, parm);
1094         local_bh_enable();
1095         return rc;
1096 }
1097 EXPORT_SYMBOL(iucv_message_reply);
1098
1099 /**
1100  * iucv_message_send
1101  * @path: address of iucv path structure
1102  * @msg: address of iucv msg structure
1103  * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1104  * @srccls: source class of message
1105  * @buffer: address of send buffer or address of struct iucv_array
1106  * @size: length of send buffer
1107  *
1108  * This function transmits data to another application. Data to be
1109  * transmitted is in a buffer and this is a one-way message and the
1110  * receiver will not reply to the message.
1111  *
1112  * Returns the result from the CP IUCV call.
1113  */
1114 int iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
1115                       u8 flags, u32 srccls, void *buffer, size_t size)
1116 {
1117         union iucv_param *parm;
1118         int rc;
1119
1120         local_bh_disable();
1121         parm = percpu_ptr(iucv_param, smp_processor_id());
1122         memset(parm, 0, sizeof(union iucv_param));
1123         if (flags & IUCV_IPRMDATA) {
1124                 /* Message of 8 bytes can be placed into the parameter list. */
1125                 parm->dpl.ippathid = path->pathid;
1126                 parm->dpl.ipflags1 = flags | IUCV_IPNORPY;
1127                 parm->dpl.iptrgcls = msg->class;
1128                 parm->dpl.ipsrccls = srccls;
1129                 parm->dpl.ipmsgtag = msg->tag;
1130                 memcpy(parm->dpl.iprmmsg, buffer, 8);
1131         } else {
1132                 parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1133                 parm->db.ipbfln1f = (u32) size;
1134                 parm->db.ippathid = path->pathid;
1135                 parm->db.ipflags1 = flags | IUCV_IPNORPY;
1136                 parm->db.iptrgcls = msg->class;
1137                 parm->db.ipsrccls = srccls;
1138                 parm->db.ipmsgtag = msg->tag;
1139         }
1140         rc = iucv_call_b2f0(IUCV_SEND, parm);
1141         if (!rc)
1142                 msg->id = parm->db.ipmsgid;
1143         local_bh_enable();
1144         return rc;
1145 }
1146 EXPORT_SYMBOL(iucv_message_send);
1147
1148 /**
1149  * iucv_message_send2way
1150  * @path: address of iucv path structure
1151  * @msg: address of iucv msg structure
1152  * @flags: how the message is sent and the reply is received
1153  *         (IUCV_IPRMDATA, IUCV_IPBUFLST, IUCV_IPPRTY, IUCV_ANSLST)
1154  * @srccls: source class of message
1155  * @buffer: address of send buffer or address of struct iucv_array
1156  * @size: length of send buffer
1157  * @ansbuf: address of answer buffer or address of struct iucv_array
1158  * @asize: size of reply buffer
1159  *
1160  * This function transmits data to another application. Data to be
1161  * transmitted is in a buffer. The receiver of the send is expected to
1162  * reply to the message and a buffer is provided into which IUCV moves
1163  * the reply to this message.
1164  *
1165  * Returns the result from the CP IUCV call.
1166  */
1167 int iucv_message_send2way(struct iucv_path *path, struct iucv_message *msg,
1168                           u8 flags, u32 srccls, void *buffer, size_t size,
1169                           void *answer, size_t asize, size_t *residual)
1170 {
1171         union iucv_param *parm;
1172         int rc;
1173
1174         local_bh_disable();
1175         parm = percpu_ptr(iucv_param, smp_processor_id());
1176         memset(parm, 0, sizeof(union iucv_param));
1177         if (flags & IUCV_IPRMDATA) {
1178                 parm->dpl.ippathid = path->pathid;
1179                 parm->dpl.ipflags1 = path->flags;       /* priority message */
1180                 parm->dpl.iptrgcls = msg->class;
1181                 parm->dpl.ipsrccls = srccls;
1182                 parm->dpl.ipmsgtag = msg->tag;
1183                 parm->dpl.ipbfadr2 = (u32)(addr_t) answer;
1184                 parm->dpl.ipbfln2f = (u32) asize;
1185                 memcpy(parm->dpl.iprmmsg, buffer, 8);
1186         } else {
1187                 parm->db.ippathid = path->pathid;
1188                 parm->db.ipflags1 = path->flags;        /* priority message */
1189                 parm->db.iptrgcls = msg->class;
1190                 parm->db.ipsrccls = srccls;
1191                 parm->db.ipmsgtag = msg->tag;
1192                 parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1193                 parm->db.ipbfln1f = (u32) size;
1194                 parm->db.ipbfadr2 = (u32)(addr_t) answer;
1195                 parm->db.ipbfln2f = (u32) asize;
1196         }
1197         rc = iucv_call_b2f0(IUCV_SEND, parm);
1198         if (!rc)
1199                 msg->id = parm->db.ipmsgid;
1200         local_bh_enable();
1201         return rc;
1202 }
1203 EXPORT_SYMBOL(iucv_message_send2way);
1204
1205 /**
1206  * iucv_path_pending
1207  * @data: Pointer to external interrupt buffer
1208  *
1209  * Process connection pending work item. Called from tasklet while holding
1210  * iucv_table_lock.
1211  */
1212 struct iucv_path_pending {
1213         u16 ippathid;
1214         u8  ipflags1;
1215         u8  iptype;
1216         u16 ipmsglim;
1217         u16 res1;
1218         u8  ipvmid[8];
1219         u8  ipuser[16];
1220         u32 res3;
1221         u8  ippollfg;
1222         u8  res4[3];
1223 } __attribute__ ((packed));
1224
1225 static void iucv_path_pending(struct iucv_irq_data *data)
1226 {
1227         struct iucv_path_pending *ipp = (void *) data;
1228         struct iucv_handler *handler;
1229         struct iucv_path *path;
1230         char *error;
1231
1232         BUG_ON(iucv_path_table[ipp->ippathid]);
1233         /* New pathid, handler found. Create a new path struct. */
1234         error = iucv_error_no_memory;
1235         path = iucv_path_alloc(ipp->ipmsglim, ipp->ipflags1, GFP_ATOMIC);
1236         if (!path)
1237                 goto out_sever;
1238         path->pathid = ipp->ippathid;
1239         iucv_path_table[path->pathid] = path;
1240         EBCASC(ipp->ipvmid, 8);
1241
1242         /* Call registered handler until one is found that wants the path. */
1243         list_for_each_entry(handler, &iucv_handler_list, list) {
1244                 if (!handler->path_pending)
1245                         continue;
1246                 /*
1247                  * Add path to handler to allow a call to iucv_path_sever
1248                  * inside the path_pending function. If the handler returns
1249                  * an error remove the path from the handler again.
1250                  */
1251                 list_add(&path->list, &handler->paths);
1252                 path->handler = handler;
1253                 if (!handler->path_pending(path, ipp->ipvmid, ipp->ipuser))
1254                         return;
1255                 list_del(&path->list);
1256                 path->handler = NULL;
1257         }
1258         /* No handler wanted the path. */
1259         iucv_path_table[path->pathid] = NULL;
1260         iucv_path_free(path);
1261         error = iucv_error_no_listener;
1262 out_sever:
1263         iucv_sever_pathid(ipp->ippathid, error);
1264 }
1265
1266 /**
1267  * iucv_path_complete
1268  * @data: Pointer to external interrupt buffer
1269  *
1270  * Process connection complete work item. Called from tasklet while holding
1271  * iucv_table_lock.
1272  */
1273 struct iucv_path_complete {
1274         u16 ippathid;
1275         u8  ipflags1;
1276         u8  iptype;
1277         u16 ipmsglim;
1278         u16 res1;
1279         u8  res2[8];
1280         u8  ipuser[16];
1281         u32 res3;
1282         u8  ippollfg;
1283         u8  res4[3];
1284 } __attribute__ ((packed));
1285
1286 static void iucv_path_complete(struct iucv_irq_data *data)
1287 {
1288         struct iucv_path_complete *ipc = (void *) data;
1289         struct iucv_path *path = iucv_path_table[ipc->ippathid];
1290
1291         if (path && path->handler && path->handler->path_complete)
1292                 path->handler->path_complete(path, ipc->ipuser);
1293 }
1294
1295 /**
1296  * iucv_path_severed
1297  * @data: Pointer to external interrupt buffer
1298  *
1299  * Process connection severed work item. Called from tasklet while holding
1300  * iucv_table_lock.
1301  */
1302 struct iucv_path_severed {
1303         u16 ippathid;
1304         u8  res1;
1305         u8  iptype;
1306         u32 res2;
1307         u8  res3[8];
1308         u8  ipuser[16];
1309         u32 res4;
1310         u8  ippollfg;
1311         u8  res5[3];
1312 } __attribute__ ((packed));
1313
1314 static void iucv_path_severed(struct iucv_irq_data *data)
1315 {
1316         struct iucv_path_severed *ips = (void *) data;
1317         struct iucv_path *path = iucv_path_table[ips->ippathid];
1318
1319         if (!path || !path->handler)    /* Already severed */
1320                 return;
1321         if (path->handler->path_severed)
1322                 path->handler->path_severed(path, ips->ipuser);
1323         else {
1324                 iucv_sever_pathid(path->pathid, NULL);
1325                 iucv_path_table[path->pathid] = NULL;
1326                 list_del_init(&path->list);
1327                 iucv_path_free(path);
1328         }
1329 }
1330
1331 /**
1332  * iucv_path_quiesced
1333  * @data: Pointer to external interrupt buffer
1334  *
1335  * Process connection quiesced work item. Called from tasklet while holding
1336  * iucv_table_lock.
1337  */
1338 struct iucv_path_quiesced {
1339         u16 ippathid;
1340         u8  res1;
1341         u8  iptype;
1342         u32 res2;
1343         u8  res3[8];
1344         u8  ipuser[16];
1345         u32 res4;
1346         u8  ippollfg;
1347         u8  res5[3];
1348 } __attribute__ ((packed));
1349
1350 static void iucv_path_quiesced(struct iucv_irq_data *data)
1351 {
1352         struct iucv_path_quiesced *ipq = (void *) data;
1353         struct iucv_path *path = iucv_path_table[ipq->ippathid];
1354
1355         if (path && path->handler && path->handler->path_quiesced)
1356                 path->handler->path_quiesced(path, ipq->ipuser);
1357 }
1358
1359 /**
1360  * iucv_path_resumed
1361  * @data: Pointer to external interrupt buffer
1362  *
1363  * Process connection resumed work item. Called from tasklet while holding
1364  * iucv_table_lock.
1365  */
1366 struct iucv_path_resumed {
1367         u16 ippathid;
1368         u8  res1;
1369         u8  iptype;
1370         u32 res2;
1371         u8  res3[8];
1372         u8  ipuser[16];
1373         u32 res4;
1374         u8  ippollfg;
1375         u8  res5[3];
1376 } __attribute__ ((packed));
1377
1378 static void iucv_path_resumed(struct iucv_irq_data *data)
1379 {
1380         struct iucv_path_resumed *ipr = (void *) data;
1381         struct iucv_path *path = iucv_path_table[ipr->ippathid];
1382
1383         if (path && path->handler && path->handler->path_resumed)
1384                 path->handler->path_resumed(path, ipr->ipuser);
1385 }
1386
1387 /**
1388  * iucv_message_complete
1389  * @data: Pointer to external interrupt buffer
1390  *
1391  * Process message complete work item. Called from tasklet while holding
1392  * iucv_table_lock.
1393  */
1394 struct iucv_message_complete {
1395         u16 ippathid;
1396         u8  ipflags1;
1397         u8  iptype;
1398         u32 ipmsgid;
1399         u32 ipaudit;
1400         u8  iprmmsg[8];
1401         u32 ipsrccls;
1402         u32 ipmsgtag;
1403         u32 res;
1404         u32 ipbfln2f;
1405         u8  ippollfg;
1406         u8  res2[3];
1407 } __attribute__ ((packed));
1408
1409 static void iucv_message_complete(struct iucv_irq_data *data)
1410 {
1411         struct iucv_message_complete *imc = (void *) data;
1412         struct iucv_path *path = iucv_path_table[imc->ippathid];
1413         struct iucv_message msg;
1414
1415         if (path && path->handler && path->handler->message_complete) {
1416                 msg.flags = imc->ipflags1;
1417                 msg.id = imc->ipmsgid;
1418                 msg.audit = imc->ipaudit;
1419                 memcpy(msg.rmmsg, imc->iprmmsg, 8);
1420                 msg.class = imc->ipsrccls;
1421                 msg.tag = imc->ipmsgtag;
1422                 msg.length = imc->ipbfln2f;
1423                 path->handler->message_complete(path, &msg);
1424         }
1425 }
1426
1427 /**
1428  * iucv_message_pending
1429  * @data: Pointer to external interrupt buffer
1430  *
1431  * Process message pending work item. Called from tasklet while holding
1432  * iucv_table_lock.
1433  */
1434 struct iucv_message_pending {
1435         u16 ippathid;
1436         u8  ipflags1;
1437         u8  iptype;
1438         u32 ipmsgid;
1439         u32 iptrgcls;
1440         union {
1441                 u32 iprmmsg1_u32;
1442                 u8  iprmmsg1[4];
1443         } ln1msg1;
1444         union {
1445                 u32 ipbfln1f;
1446                 u8  iprmmsg2[4];
1447         } ln1msg2;
1448         u32 res1[3];
1449         u32 ipbfln2f;
1450         u8  ippollfg;
1451         u8  res2[3];
1452 } __attribute__ ((packed));
1453
1454 static void iucv_message_pending(struct iucv_irq_data *data)
1455 {
1456         struct iucv_message_pending *imp = (void *) data;
1457         struct iucv_path *path = iucv_path_table[imp->ippathid];
1458         struct iucv_message msg;
1459
1460         if (path && path->handler && path->handler->message_pending) {
1461                 msg.flags = imp->ipflags1;
1462                 msg.id = imp->ipmsgid;
1463                 msg.class = imp->iptrgcls;
1464                 if (imp->ipflags1 & IUCV_IPRMDATA) {
1465                         memcpy(msg.rmmsg, imp->ln1msg1.iprmmsg1, 8);
1466                         msg.length = 8;
1467                 } else
1468                         msg.length = imp->ln1msg2.ipbfln1f;
1469                 msg.reply_size = imp->ipbfln2f;
1470                 path->handler->message_pending(path, &msg);
1471         }
1472 }
1473
1474 /**
1475  * iucv_tasklet_fn:
1476  *
1477  * This tasklet loops over the queue of irq buffers created by
1478  * iucv_external_interrupt, calls the appropriate action handler
1479  * and then frees the buffer.
1480  */
1481 static void iucv_tasklet_fn(unsigned long ignored)
1482 {
1483         typedef void iucv_irq_fn(struct iucv_irq_data *);
1484         static iucv_irq_fn *irq_fn[] = {
1485                 [0x02] = iucv_path_complete,
1486                 [0x03] = iucv_path_severed,
1487                 [0x04] = iucv_path_quiesced,
1488                 [0x05] = iucv_path_resumed,
1489                 [0x06] = iucv_message_complete,
1490                 [0x07] = iucv_message_complete,
1491                 [0x08] = iucv_message_pending,
1492                 [0x09] = iucv_message_pending,
1493         };
1494         struct list_head task_queue = LIST_HEAD_INIT(task_queue);
1495         struct iucv_irq_list *p, *n;
1496
1497         /* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1498         if (!spin_trylock(&iucv_table_lock)) {
1499                 tasklet_schedule(&iucv_tasklet);
1500                 return;
1501         }
1502         iucv_active_cpu = smp_processor_id();
1503
1504         spin_lock_irq(&iucv_queue_lock);
1505         list_splice_init(&iucv_task_queue, &task_queue);
1506         spin_unlock_irq(&iucv_queue_lock);
1507
1508         list_for_each_entry_safe(p, n, &task_queue, list) {
1509                 list_del_init(&p->list);
1510                 irq_fn[p->data.iptype](&p->data);
1511                 kfree(p);
1512         }
1513
1514         iucv_active_cpu = -1;
1515         spin_unlock(&iucv_table_lock);
1516 }
1517
1518 /**
1519  * iucv_work_fn:
1520  *
1521  * This work function loops over the queue of path pending irq blocks
1522  * created by iucv_external_interrupt, calls the appropriate action
1523  * handler and then frees the buffer.
1524  */
1525 static void iucv_work_fn(struct work_struct *work)
1526 {
1527         typedef void iucv_irq_fn(struct iucv_irq_data *);
1528         struct list_head work_queue = LIST_HEAD_INIT(work_queue);
1529         struct iucv_irq_list *p, *n;
1530
1531         /* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1532         spin_lock_bh(&iucv_table_lock);
1533         iucv_active_cpu = smp_processor_id();
1534
1535         spin_lock_irq(&iucv_queue_lock);
1536         list_splice_init(&iucv_work_queue, &work_queue);
1537         spin_unlock_irq(&iucv_queue_lock);
1538
1539         iucv_cleanup_queue();
1540         list_for_each_entry_safe(p, n, &work_queue, list) {
1541                 list_del_init(&p->list);
1542                 iucv_path_pending(&p->data);
1543                 kfree(p);
1544         }
1545
1546         iucv_active_cpu = -1;
1547         spin_unlock_bh(&iucv_table_lock);
1548 }
1549
1550 /**
1551  * iucv_external_interrupt
1552  * @code: irq code
1553  *
1554  * Handles external interrupts coming in from CP.
1555  * Places the interrupt buffer on a queue and schedules iucv_tasklet_fn().
1556  */
1557 static void iucv_external_interrupt(u16 code)
1558 {
1559         struct iucv_irq_data *p;
1560         struct iucv_irq_list *work;
1561
1562         p = percpu_ptr(iucv_irq_data, smp_processor_id());
1563         if (p->ippathid >= iucv_max_pathid) {
1564                 printk(KERN_WARNING "iucv_do_int: Got interrupt with "
1565                        "pathid %d > max_connections (%ld)\n",
1566                        p->ippathid, iucv_max_pathid - 1);
1567                 iucv_sever_pathid(p->ippathid, iucv_error_no_listener);
1568                 return;
1569         }
1570         if (p->iptype  < 0x01 || p->iptype > 0x09) {
1571                 printk(KERN_ERR "iucv_do_int: unknown iucv interrupt\n");
1572                 return;
1573         }
1574         work = kmalloc(sizeof(struct iucv_irq_list), GFP_ATOMIC);
1575         if (!work) {
1576                 printk(KERN_WARNING "iucv_external_interrupt: out of memory\n");
1577                 return;
1578         }
1579         memcpy(&work->data, p, sizeof(work->data));
1580         spin_lock(&iucv_queue_lock);
1581         if (p->iptype == 0x01) {
1582                 /* Path pending interrupt. */
1583                 list_add_tail(&work->list, &iucv_work_queue);
1584                 schedule_work(&iucv_work);
1585         } else {
1586                 /* The other interrupts. */
1587                 list_add_tail(&work->list, &iucv_task_queue);
1588                 tasklet_schedule(&iucv_tasklet);
1589         }
1590         spin_unlock(&iucv_queue_lock);
1591 }
1592
1593 /**
1594  * iucv_init
1595  *
1596  * Allocates and initializes various data structures.
1597  */
1598 static int __init iucv_init(void)
1599 {
1600         int rc;
1601
1602         if (!MACHINE_IS_VM) {
1603                 rc = -EPROTONOSUPPORT;
1604                 goto out;
1605         }
1606         rc = iucv_query_maxconn();
1607         if (rc)
1608                 goto out;
1609         rc = register_external_interrupt(0x4000, iucv_external_interrupt);
1610         if (rc)
1611                 goto out;
1612         rc = bus_register(&iucv_bus);
1613         if (rc)
1614                 goto out_int;
1615         iucv_root = s390_root_dev_register("iucv");
1616         if (IS_ERR(iucv_root)) {
1617                 rc = PTR_ERR(iucv_root);
1618                 goto out_bus;
1619         }
1620         /* Note: GFP_DMA used to get memory below 2G */
1621         iucv_irq_data = percpu_alloc(sizeof(struct iucv_irq_data),
1622                                      GFP_KERNEL|GFP_DMA);
1623         if (!iucv_irq_data) {
1624                 rc = -ENOMEM;
1625                 goto out_root;
1626         }
1627         /* Allocate parameter blocks. */
1628         iucv_param = percpu_alloc(sizeof(union iucv_param),
1629                                   GFP_KERNEL|GFP_DMA);
1630         if (!iucv_param) {
1631                 rc = -ENOMEM;
1632                 goto out_extint;
1633         }
1634         register_hotcpu_notifier(&iucv_cpu_notifier);
1635         ASCEBC(iucv_error_no_listener, 16);
1636         ASCEBC(iucv_error_no_memory, 16);
1637         ASCEBC(iucv_error_pathid, 16);
1638         iucv_available = 1;
1639         return 0;
1640
1641 out_extint:
1642         percpu_free(iucv_irq_data);
1643 out_root:
1644         s390_root_dev_unregister(iucv_root);
1645 out_bus:
1646         bus_unregister(&iucv_bus);
1647 out_int:
1648         unregister_external_interrupt(0x4000, iucv_external_interrupt);
1649 out:
1650         return rc;
1651 }
1652
1653 /**
1654  * iucv_exit
1655  *
1656  * Frees everything allocated from iucv_init.
1657  */
1658 static void __exit iucv_exit(void)
1659 {
1660         struct iucv_irq_list *p, *n;
1661
1662         spin_lock_irq(&iucv_queue_lock);
1663         list_for_each_entry_safe(p, n, &iucv_task_queue, list)
1664                 kfree(p);
1665         list_for_each_entry_safe(p, n, &iucv_work_queue, list)
1666                 kfree(p);
1667         spin_unlock_irq(&iucv_queue_lock);
1668         unregister_hotcpu_notifier(&iucv_cpu_notifier);
1669         percpu_free(iucv_param);
1670         percpu_free(iucv_irq_data);
1671         s390_root_dev_unregister(iucv_root);
1672         bus_unregister(&iucv_bus);
1673         unregister_external_interrupt(0x4000, iucv_external_interrupt);
1674 }
1675
1676 subsys_initcall(iucv_init);
1677 module_exit(iucv_exit);
1678
1679 MODULE_AUTHOR("(C) 2001 IBM Corp. by Fritz Elfert (felfert@millenux.com)");
1680 MODULE_DESCRIPTION("Linux for S/390 IUCV lowlevel driver");
1681 MODULE_LICENSE("GPL");