xref: /linux/net/iucv/iucv.c (revision d524dac9279b6a41ffdf7ff7958c577f2e387db6)
1 /*
2  * IUCV base infrastructure.
3  *
4  * Copyright IBM Corp. 2001, 2009
5  *
6  * Author(s):
7  *    Original source:
8  *	Alan Altmark (Alan_Altmark@us.ibm.com)	Sept. 2000
9  *	Xenia Tkatschow (xenia@us.ibm.com)
10  *    2Gb awareness and general cleanup:
11  *	Fritz Elfert (elfert@de.ibm.com, felfert@millenux.com)
12  *    Rewritten for af_iucv:
13  *	Martin Schwidefsky <schwidefsky@de.ibm.com>
14  *    PM functions:
15  *	Ursula Braun (ursula.braun@de.ibm.com)
16  *
17  * Documentation used:
18  *    The original source
19  *    CP Programming Service, IBM document # SC24-5760
20  *
21  * This program is free software; you can redistribute it and/or modify
22  * it under the terms of the GNU General Public License as published by
23  * the Free Software Foundation; either version 2, or (at your option)
24  * any later version.
25  *
26  * This program is distributed in the hope that it will be useful,
27  * but WITHOUT ANY WARRANTY; without even the implied warranty of
28  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
29  * GNU General Public License for more details.
30  *
31  * You should have received a copy of the GNU General Public License
32  * along with this program; if not, write to the Free Software
33  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
34  */
35 
36 #define KMSG_COMPONENT "iucv"
37 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
38 
39 #include <linux/kernel_stat.h>
40 #include <linux/module.h>
41 #include <linux/moduleparam.h>
42 #include <linux/spinlock.h>
43 #include <linux/kernel.h>
44 #include <linux/slab.h>
45 #include <linux/init.h>
46 #include <linux/interrupt.h>
47 #include <linux/list.h>
48 #include <linux/errno.h>
49 #include <linux/err.h>
50 #include <linux/device.h>
51 #include <linux/cpu.h>
52 #include <linux/reboot.h>
53 #include <net/iucv/iucv.h>
54 #include <asm/atomic.h>
55 #include <asm/ebcdic.h>
56 #include <asm/io.h>
57 #include <asm/s390_ext.h>
58 #include <asm/smp.h>
59 
60 /*
61  * FLAGS:
62  * All flags are defined in the field IPFLAGS1 of each function
63  * and can be found in CP Programming Services.
64  * IPSRCCLS - Indicates you have specified a source class.
65  * IPTRGCLS - Indicates you have specified a target class.
66  * IPFGPID  - Indicates you have specified a pathid.
67  * IPFGMID  - Indicates you have specified a message ID.
68  * IPNORPY  - Indicates a one-way message. No reply expected.
69  * IPALL    - Indicates that all paths are affected.
70  */
71 #define IUCV_IPSRCCLS	0x01
72 #define IUCV_IPTRGCLS	0x01
73 #define IUCV_IPFGPID	0x02
74 #define IUCV_IPFGMID	0x04
75 #define IUCV_IPNORPY	0x10
76 #define IUCV_IPALL	0x80
77 
78 static int iucv_bus_match(struct device *dev, struct device_driver *drv)
79 {
80 	return 0;
81 }
82 
83 enum iucv_pm_states {
84 	IUCV_PM_INITIAL = 0,
85 	IUCV_PM_FREEZING = 1,
86 	IUCV_PM_THAWING = 2,
87 	IUCV_PM_RESTORING = 3,
88 };
89 static enum iucv_pm_states iucv_pm_state;
90 
91 static int iucv_pm_prepare(struct device *);
92 static void iucv_pm_complete(struct device *);
93 static int iucv_pm_freeze(struct device *);
94 static int iucv_pm_thaw(struct device *);
95 static int iucv_pm_restore(struct device *);
96 
97 static const struct dev_pm_ops iucv_pm_ops = {
98 	.prepare = iucv_pm_prepare,
99 	.complete = iucv_pm_complete,
100 	.freeze = iucv_pm_freeze,
101 	.thaw = iucv_pm_thaw,
102 	.restore = iucv_pm_restore,
103 };
104 
105 struct bus_type iucv_bus = {
106 	.name = "iucv",
107 	.match = iucv_bus_match,
108 	.pm = &iucv_pm_ops,
109 };
110 EXPORT_SYMBOL(iucv_bus);
111 
112 struct device *iucv_root;
113 EXPORT_SYMBOL(iucv_root);
114 
115 static int iucv_available;
116 
117 /* General IUCV interrupt structure */
118 struct iucv_irq_data {
119 	u16 ippathid;
120 	u8  ipflags1;
121 	u8  iptype;
122 	u32 res2[8];
123 };
124 
125 struct iucv_irq_list {
126 	struct list_head list;
127 	struct iucv_irq_data data;
128 };
129 
130 static struct iucv_irq_data *iucv_irq_data[NR_CPUS];
131 static cpumask_t iucv_buffer_cpumask = CPU_MASK_NONE;
132 static cpumask_t iucv_irq_cpumask = CPU_MASK_NONE;
133 
134 /*
135  * Queue of interrupt buffers lock for delivery via the tasklet
136  * (fast but can't call smp_call_function).
137  */
138 static LIST_HEAD(iucv_task_queue);
139 
140 /*
141  * The tasklet for fast delivery of iucv interrupts.
142  */
143 static void iucv_tasklet_fn(unsigned long);
144 static DECLARE_TASKLET(iucv_tasklet, iucv_tasklet_fn,0);
145 
146 /*
147  * Queue of interrupt buffers for delivery via a work queue
148  * (slower but can call smp_call_function).
149  */
150 static LIST_HEAD(iucv_work_queue);
151 
152 /*
153  * The work element to deliver path pending interrupts.
154  */
155 static void iucv_work_fn(struct work_struct *work);
156 static DECLARE_WORK(iucv_work, iucv_work_fn);
157 
158 /*
159  * Spinlock protecting task and work queue.
160  */
161 static DEFINE_SPINLOCK(iucv_queue_lock);
162 
163 enum iucv_command_codes {
164 	IUCV_QUERY = 0,
165 	IUCV_RETRIEVE_BUFFER = 2,
166 	IUCV_SEND = 4,
167 	IUCV_RECEIVE = 5,
168 	IUCV_REPLY = 6,
169 	IUCV_REJECT = 8,
170 	IUCV_PURGE = 9,
171 	IUCV_ACCEPT = 10,
172 	IUCV_CONNECT = 11,
173 	IUCV_DECLARE_BUFFER = 12,
174 	IUCV_QUIESCE = 13,
175 	IUCV_RESUME = 14,
176 	IUCV_SEVER = 15,
177 	IUCV_SETMASK = 16,
178 	IUCV_SETCONTROLMASK = 17,
179 };
180 
181 /*
182  * Error messages that are used with the iucv_sever function. They get
183  * converted to EBCDIC.
184  */
185 static char iucv_error_no_listener[16] = "NO LISTENER";
186 static char iucv_error_no_memory[16] = "NO MEMORY";
187 static char iucv_error_pathid[16] = "INVALID PATHID";
188 
189 /*
190  * iucv_handler_list: List of registered handlers.
191  */
192 static LIST_HEAD(iucv_handler_list);
193 
194 /*
195  * iucv_path_table: an array of iucv_path structures.
196  */
197 static struct iucv_path **iucv_path_table;
198 static unsigned long iucv_max_pathid;
199 
200 /*
201  * iucv_lock: spinlock protecting iucv_handler_list and iucv_pathid_table
202  */
203 static DEFINE_SPINLOCK(iucv_table_lock);
204 
205 /*
206  * iucv_active_cpu: contains the number of the cpu executing the tasklet
207  * or the work handler. Needed for iucv_path_sever called from tasklet.
208  */
209 static int iucv_active_cpu = -1;
210 
211 /*
212  * Mutex and wait queue for iucv_register/iucv_unregister.
213  */
214 static DEFINE_MUTEX(iucv_register_mutex);
215 
216 /*
217  * Counter for number of non-smp capable handlers.
218  */
219 static int iucv_nonsmp_handler;
220 
221 /*
222  * IUCV control data structure. Used by iucv_path_accept, iucv_path_connect,
223  * iucv_path_quiesce and iucv_path_sever.
224  */
225 struct iucv_cmd_control {
226 	u16 ippathid;
227 	u8  ipflags1;
228 	u8  iprcode;
229 	u16 ipmsglim;
230 	u16 res1;
231 	u8  ipvmid[8];
232 	u8  ipuser[16];
233 	u8  iptarget[8];
234 } __attribute__ ((packed,aligned(8)));
235 
236 /*
237  * Data in parameter list iucv structure. Used by iucv_message_send,
238  * iucv_message_send2way and iucv_message_reply.
239  */
240 struct iucv_cmd_dpl {
241 	u16 ippathid;
242 	u8  ipflags1;
243 	u8  iprcode;
244 	u32 ipmsgid;
245 	u32 iptrgcls;
246 	u8  iprmmsg[8];
247 	u32 ipsrccls;
248 	u32 ipmsgtag;
249 	u32 ipbfadr2;
250 	u32 ipbfln2f;
251 	u32 res;
252 } __attribute__ ((packed,aligned(8)));
253 
254 /*
255  * Data in buffer iucv structure. Used by iucv_message_receive,
256  * iucv_message_reject, iucv_message_send, iucv_message_send2way
257  * and iucv_declare_cpu.
258  */
259 struct iucv_cmd_db {
260 	u16 ippathid;
261 	u8  ipflags1;
262 	u8  iprcode;
263 	u32 ipmsgid;
264 	u32 iptrgcls;
265 	u32 ipbfadr1;
266 	u32 ipbfln1f;
267 	u32 ipsrccls;
268 	u32 ipmsgtag;
269 	u32 ipbfadr2;
270 	u32 ipbfln2f;
271 	u32 res;
272 } __attribute__ ((packed,aligned(8)));
273 
274 /*
275  * Purge message iucv structure. Used by iucv_message_purge.
276  */
277 struct iucv_cmd_purge {
278 	u16 ippathid;
279 	u8  ipflags1;
280 	u8  iprcode;
281 	u32 ipmsgid;
282 	u8  ipaudit[3];
283 	u8  res1[5];
284 	u32 res2;
285 	u32 ipsrccls;
286 	u32 ipmsgtag;
287 	u32 res3[3];
288 } __attribute__ ((packed,aligned(8)));
289 
290 /*
291  * Set mask iucv structure. Used by iucv_enable_cpu.
292  */
293 struct iucv_cmd_set_mask {
294 	u8  ipmask;
295 	u8  res1[2];
296 	u8  iprcode;
297 	u32 res2[9];
298 } __attribute__ ((packed,aligned(8)));
299 
300 union iucv_param {
301 	struct iucv_cmd_control ctrl;
302 	struct iucv_cmd_dpl dpl;
303 	struct iucv_cmd_db db;
304 	struct iucv_cmd_purge purge;
305 	struct iucv_cmd_set_mask set_mask;
306 };
307 
308 /*
309  * Anchor for per-cpu IUCV command parameter block.
310  */
311 static union iucv_param *iucv_param[NR_CPUS];
312 static union iucv_param *iucv_param_irq[NR_CPUS];
313 
314 /**
315  * iucv_call_b2f0
316  * @code: identifier of IUCV call to CP.
317  * @parm: pointer to a struct iucv_parm block
318  *
319  * Calls CP to execute IUCV commands.
320  *
321  * Returns the result of the CP IUCV call.
322  */
323 static inline int iucv_call_b2f0(int command, union iucv_param *parm)
324 {
325 	register unsigned long reg0 asm ("0");
326 	register unsigned long reg1 asm ("1");
327 	int ccode;
328 
329 	reg0 = command;
330 	reg1 = virt_to_phys(parm);
331 	asm volatile(
332 		"	.long 0xb2f01000\n"
333 		"	ipm	%0\n"
334 		"	srl	%0,28\n"
335 		: "=d" (ccode), "=m" (*parm), "+d" (reg0), "+a" (reg1)
336 		:  "m" (*parm) : "cc");
337 	return (ccode == 1) ? parm->ctrl.iprcode : ccode;
338 }
339 
340 /**
341  * iucv_query_maxconn
342  *
343  * Determines the maximum number of connections that may be established.
344  *
345  * Returns the maximum number of connections or -EPERM is IUCV is not
346  * available.
347  */
348 static int iucv_query_maxconn(void)
349 {
350 	register unsigned long reg0 asm ("0");
351 	register unsigned long reg1 asm ("1");
352 	void *param;
353 	int ccode;
354 
355 	param = kzalloc(sizeof(union iucv_param), GFP_KERNEL|GFP_DMA);
356 	if (!param)
357 		return -ENOMEM;
358 	reg0 = IUCV_QUERY;
359 	reg1 = (unsigned long) param;
360 	asm volatile (
361 		"	.long	0xb2f01000\n"
362 		"	ipm	%0\n"
363 		"	srl	%0,28\n"
364 		: "=d" (ccode), "+d" (reg0), "+d" (reg1) : : "cc");
365 	if (ccode == 0)
366 		iucv_max_pathid = reg1;
367 	kfree(param);
368 	return ccode ? -EPERM : 0;
369 }
370 
371 /**
372  * iucv_allow_cpu
373  * @data: unused
374  *
375  * Allow iucv interrupts on this cpu.
376  */
377 static void iucv_allow_cpu(void *data)
378 {
379 	int cpu = smp_processor_id();
380 	union iucv_param *parm;
381 
382 	/*
383 	 * Enable all iucv interrupts.
384 	 * ipmask contains bits for the different interrupts
385 	 *	0x80 - Flag to allow nonpriority message pending interrupts
386 	 *	0x40 - Flag to allow priority message pending interrupts
387 	 *	0x20 - Flag to allow nonpriority message completion interrupts
388 	 *	0x10 - Flag to allow priority message completion interrupts
389 	 *	0x08 - Flag to allow IUCV control interrupts
390 	 */
391 	parm = iucv_param_irq[cpu];
392 	memset(parm, 0, sizeof(union iucv_param));
393 	parm->set_mask.ipmask = 0xf8;
394 	iucv_call_b2f0(IUCV_SETMASK, parm);
395 
396 	/*
397 	 * Enable all iucv control interrupts.
398 	 * ipmask contains bits for the different interrupts
399 	 *	0x80 - Flag to allow pending connections interrupts
400 	 *	0x40 - Flag to allow connection complete interrupts
401 	 *	0x20 - Flag to allow connection severed interrupts
402 	 *	0x10 - Flag to allow connection quiesced interrupts
403 	 *	0x08 - Flag to allow connection resumed interrupts
404 	 */
405 	memset(parm, 0, sizeof(union iucv_param));
406 	parm->set_mask.ipmask = 0xf8;
407 	iucv_call_b2f0(IUCV_SETCONTROLMASK, parm);
408 	/* Set indication that iucv interrupts are allowed for this cpu. */
409 	cpu_set(cpu, iucv_irq_cpumask);
410 }
411 
412 /**
413  * iucv_block_cpu
414  * @data: unused
415  *
416  * Block iucv interrupts on this cpu.
417  */
418 static void iucv_block_cpu(void *data)
419 {
420 	int cpu = smp_processor_id();
421 	union iucv_param *parm;
422 
423 	/* Disable all iucv interrupts. */
424 	parm = iucv_param_irq[cpu];
425 	memset(parm, 0, sizeof(union iucv_param));
426 	iucv_call_b2f0(IUCV_SETMASK, parm);
427 
428 	/* Clear indication that iucv interrupts are allowed for this cpu. */
429 	cpu_clear(cpu, iucv_irq_cpumask);
430 }
431 
432 /**
433  * iucv_block_cpu_almost
434  * @data: unused
435  *
436  * Allow connection-severed interrupts only on this cpu.
437  */
438 static void iucv_block_cpu_almost(void *data)
439 {
440 	int cpu = smp_processor_id();
441 	union iucv_param *parm;
442 
443 	/* Allow iucv control interrupts only */
444 	parm = iucv_param_irq[cpu];
445 	memset(parm, 0, sizeof(union iucv_param));
446 	parm->set_mask.ipmask = 0x08;
447 	iucv_call_b2f0(IUCV_SETMASK, parm);
448 	/* Allow iucv-severed interrupt only */
449 	memset(parm, 0, sizeof(union iucv_param));
450 	parm->set_mask.ipmask = 0x20;
451 	iucv_call_b2f0(IUCV_SETCONTROLMASK, parm);
452 
453 	/* Clear indication that iucv interrupts are allowed for this cpu. */
454 	cpu_clear(cpu, iucv_irq_cpumask);
455 }
456 
457 /**
458  * iucv_declare_cpu
459  * @data: unused
460  *
461  * Declare a interrupt buffer on this cpu.
462  */
463 static void iucv_declare_cpu(void *data)
464 {
465 	int cpu = smp_processor_id();
466 	union iucv_param *parm;
467 	int rc;
468 
469 	if (cpu_isset(cpu, iucv_buffer_cpumask))
470 		return;
471 
472 	/* Declare interrupt buffer. */
473 	parm = iucv_param_irq[cpu];
474 	memset(parm, 0, sizeof(union iucv_param));
475 	parm->db.ipbfadr1 = virt_to_phys(iucv_irq_data[cpu]);
476 	rc = iucv_call_b2f0(IUCV_DECLARE_BUFFER, parm);
477 	if (rc) {
478 		char *err = "Unknown";
479 		switch (rc) {
480 		case 0x03:
481 			err = "Directory error";
482 			break;
483 		case 0x0a:
484 			err = "Invalid length";
485 			break;
486 		case 0x13:
487 			err = "Buffer already exists";
488 			break;
489 		case 0x3e:
490 			err = "Buffer overlap";
491 			break;
492 		case 0x5c:
493 			err = "Paging or storage error";
494 			break;
495 		}
496 		pr_warning("Defining an interrupt buffer on CPU %i"
497 			   " failed with 0x%02x (%s)\n", cpu, rc, err);
498 		return;
499 	}
500 
501 	/* Set indication that an iucv buffer exists for this cpu. */
502 	cpu_set(cpu, iucv_buffer_cpumask);
503 
504 	if (iucv_nonsmp_handler == 0 || cpus_empty(iucv_irq_cpumask))
505 		/* Enable iucv interrupts on this cpu. */
506 		iucv_allow_cpu(NULL);
507 	else
508 		/* Disable iucv interrupts on this cpu. */
509 		iucv_block_cpu(NULL);
510 }
511 
512 /**
513  * iucv_retrieve_cpu
514  * @data: unused
515  *
516  * Retrieve interrupt buffer on this cpu.
517  */
518 static void iucv_retrieve_cpu(void *data)
519 {
520 	int cpu = smp_processor_id();
521 	union iucv_param *parm;
522 
523 	if (!cpu_isset(cpu, iucv_buffer_cpumask))
524 		return;
525 
526 	/* Block iucv interrupts. */
527 	iucv_block_cpu(NULL);
528 
529 	/* Retrieve interrupt buffer. */
530 	parm = iucv_param_irq[cpu];
531 	iucv_call_b2f0(IUCV_RETRIEVE_BUFFER, parm);
532 
533 	/* Clear indication that an iucv buffer exists for this cpu. */
534 	cpu_clear(cpu, iucv_buffer_cpumask);
535 }
536 
537 /**
538  * iucv_setmask_smp
539  *
540  * Allow iucv interrupts on all cpus.
541  */
542 static void iucv_setmask_mp(void)
543 {
544 	int cpu;
545 
546 	get_online_cpus();
547 	for_each_online_cpu(cpu)
548 		/* Enable all cpus with a declared buffer. */
549 		if (cpu_isset(cpu, iucv_buffer_cpumask) &&
550 		    !cpu_isset(cpu, iucv_irq_cpumask))
551 			smp_call_function_single(cpu, iucv_allow_cpu,
552 						 NULL, 1);
553 	put_online_cpus();
554 }
555 
556 /**
557  * iucv_setmask_up
558  *
559  * Allow iucv interrupts on a single cpu.
560  */
561 static void iucv_setmask_up(void)
562 {
563 	cpumask_t cpumask;
564 	int cpu;
565 
566 	/* Disable all cpu but the first in cpu_irq_cpumask. */
567 	cpumask = iucv_irq_cpumask;
568 	cpu_clear(first_cpu(iucv_irq_cpumask), cpumask);
569 	for_each_cpu_mask_nr(cpu, cpumask)
570 		smp_call_function_single(cpu, iucv_block_cpu, NULL, 1);
571 }
572 
573 /**
574  * iucv_enable
575  *
576  * This function makes iucv ready for use. It allocates the pathid
577  * table, declares an iucv interrupt buffer and enables the iucv
578  * interrupts. Called when the first user has registered an iucv
579  * handler.
580  */
581 static int iucv_enable(void)
582 {
583 	size_t alloc_size;
584 	int cpu, rc;
585 
586 	get_online_cpus();
587 	rc = -ENOMEM;
588 	alloc_size = iucv_max_pathid * sizeof(struct iucv_path);
589 	iucv_path_table = kzalloc(alloc_size, GFP_KERNEL);
590 	if (!iucv_path_table)
591 		goto out;
592 	/* Declare per cpu buffers. */
593 	rc = -EIO;
594 	for_each_online_cpu(cpu)
595 		smp_call_function_single(cpu, iucv_declare_cpu, NULL, 1);
596 	if (cpus_empty(iucv_buffer_cpumask))
597 		/* No cpu could declare an iucv buffer. */
598 		goto out;
599 	put_online_cpus();
600 	return 0;
601 out:
602 	kfree(iucv_path_table);
603 	iucv_path_table = NULL;
604 	put_online_cpus();
605 	return rc;
606 }
607 
608 /**
609  * iucv_disable
610  *
611  * This function shuts down iucv. It disables iucv interrupts, retrieves
612  * the iucv interrupt buffer and frees the pathid table. Called after the
613  * last user unregister its iucv handler.
614  */
615 static void iucv_disable(void)
616 {
617 	get_online_cpus();
618 	on_each_cpu(iucv_retrieve_cpu, NULL, 1);
619 	kfree(iucv_path_table);
620 	iucv_path_table = NULL;
621 	put_online_cpus();
622 }
623 
624 static int __cpuinit iucv_cpu_notify(struct notifier_block *self,
625 				     unsigned long action, void *hcpu)
626 {
627 	cpumask_t cpumask;
628 	long cpu = (long) hcpu;
629 
630 	switch (action) {
631 	case CPU_UP_PREPARE:
632 	case CPU_UP_PREPARE_FROZEN:
633 		iucv_irq_data[cpu] = kmalloc_node(sizeof(struct iucv_irq_data),
634 					GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
635 		if (!iucv_irq_data[cpu])
636 			return notifier_from_errno(-ENOMEM);
637 
638 		iucv_param[cpu] = kmalloc_node(sizeof(union iucv_param),
639 				     GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
640 		if (!iucv_param[cpu]) {
641 			kfree(iucv_irq_data[cpu]);
642 			iucv_irq_data[cpu] = NULL;
643 			return notifier_from_errno(-ENOMEM);
644 		}
645 		iucv_param_irq[cpu] = kmalloc_node(sizeof(union iucv_param),
646 					GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
647 		if (!iucv_param_irq[cpu]) {
648 			kfree(iucv_param[cpu]);
649 			iucv_param[cpu] = NULL;
650 			kfree(iucv_irq_data[cpu]);
651 			iucv_irq_data[cpu] = NULL;
652 			return notifier_from_errno(-ENOMEM);
653 		}
654 		break;
655 	case CPU_UP_CANCELED:
656 	case CPU_UP_CANCELED_FROZEN:
657 	case CPU_DEAD:
658 	case CPU_DEAD_FROZEN:
659 		kfree(iucv_param_irq[cpu]);
660 		iucv_param_irq[cpu] = NULL;
661 		kfree(iucv_param[cpu]);
662 		iucv_param[cpu] = NULL;
663 		kfree(iucv_irq_data[cpu]);
664 		iucv_irq_data[cpu] = NULL;
665 		break;
666 	case CPU_ONLINE:
667 	case CPU_ONLINE_FROZEN:
668 	case CPU_DOWN_FAILED:
669 	case CPU_DOWN_FAILED_FROZEN:
670 		if (!iucv_path_table)
671 			break;
672 		smp_call_function_single(cpu, iucv_declare_cpu, NULL, 1);
673 		break;
674 	case CPU_DOWN_PREPARE:
675 	case CPU_DOWN_PREPARE_FROZEN:
676 		if (!iucv_path_table)
677 			break;
678 		cpumask = iucv_buffer_cpumask;
679 		cpu_clear(cpu, cpumask);
680 		if (cpus_empty(cpumask))
681 			/* Can't offline last IUCV enabled cpu. */
682 			return notifier_from_errno(-EINVAL);
683 		smp_call_function_single(cpu, iucv_retrieve_cpu, NULL, 1);
684 		if (cpus_empty(iucv_irq_cpumask))
685 			smp_call_function_single(first_cpu(iucv_buffer_cpumask),
686 						 iucv_allow_cpu, NULL, 1);
687 		break;
688 	}
689 	return NOTIFY_OK;
690 }
691 
692 static struct notifier_block __refdata iucv_cpu_notifier = {
693 	.notifier_call = iucv_cpu_notify,
694 };
695 
696 /**
697  * iucv_sever_pathid
698  * @pathid: path identification number.
699  * @userdata: 16-bytes of user data.
700  *
701  * Sever an iucv path to free up the pathid. Used internally.
702  */
703 static int iucv_sever_pathid(u16 pathid, u8 userdata[16])
704 {
705 	union iucv_param *parm;
706 
707 	parm = iucv_param_irq[smp_processor_id()];
708 	memset(parm, 0, sizeof(union iucv_param));
709 	if (userdata)
710 		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
711 	parm->ctrl.ippathid = pathid;
712 	return iucv_call_b2f0(IUCV_SEVER, parm);
713 }
714 
715 /**
716  * __iucv_cleanup_queue
717  * @dummy: unused dummy argument
718  *
719  * Nop function called via smp_call_function to force work items from
720  * pending external iucv interrupts to the work queue.
721  */
722 static void __iucv_cleanup_queue(void *dummy)
723 {
724 }
725 
726 /**
727  * iucv_cleanup_queue
728  *
729  * Function called after a path has been severed to find all remaining
730  * work items for the now stale pathid. The caller needs to hold the
731  * iucv_table_lock.
732  */
733 static void iucv_cleanup_queue(void)
734 {
735 	struct iucv_irq_list *p, *n;
736 
737 	/*
738 	 * When a path is severed, the pathid can be reused immediatly
739 	 * on a iucv connect or a connection pending interrupt. Remove
740 	 * all entries from the task queue that refer to a stale pathid
741 	 * (iucv_path_table[ix] == NULL). Only then do the iucv connect
742 	 * or deliver the connection pending interrupt. To get all the
743 	 * pending interrupts force them to the work queue by calling
744 	 * an empty function on all cpus.
745 	 */
746 	smp_call_function(__iucv_cleanup_queue, NULL, 1);
747 	spin_lock_irq(&iucv_queue_lock);
748 	list_for_each_entry_safe(p, n, &iucv_task_queue, list) {
749 		/* Remove stale work items from the task queue. */
750 		if (iucv_path_table[p->data.ippathid] == NULL) {
751 			list_del(&p->list);
752 			kfree(p);
753 		}
754 	}
755 	spin_unlock_irq(&iucv_queue_lock);
756 }
757 
758 /**
759  * iucv_register:
760  * @handler: address of iucv handler structure
761  * @smp: != 0 indicates that the handler can deal with out of order messages
762  *
763  * Registers a driver with IUCV.
764  *
765  * Returns 0 on success, -ENOMEM if the memory allocation for the pathid
766  * table failed, or -EIO if IUCV_DECLARE_BUFFER failed on all cpus.
767  */
768 int iucv_register(struct iucv_handler *handler, int smp)
769 {
770 	int rc;
771 
772 	if (!iucv_available)
773 		return -ENOSYS;
774 	mutex_lock(&iucv_register_mutex);
775 	if (!smp)
776 		iucv_nonsmp_handler++;
777 	if (list_empty(&iucv_handler_list)) {
778 		rc = iucv_enable();
779 		if (rc)
780 			goto out_mutex;
781 	} else if (!smp && iucv_nonsmp_handler == 1)
782 		iucv_setmask_up();
783 	INIT_LIST_HEAD(&handler->paths);
784 
785 	spin_lock_bh(&iucv_table_lock);
786 	list_add_tail(&handler->list, &iucv_handler_list);
787 	spin_unlock_bh(&iucv_table_lock);
788 	rc = 0;
789 out_mutex:
790 	mutex_unlock(&iucv_register_mutex);
791 	return rc;
792 }
793 EXPORT_SYMBOL(iucv_register);
794 
795 /**
796  * iucv_unregister
797  * @handler:  address of iucv handler structure
798  * @smp: != 0 indicates that the handler can deal with out of order messages
799  *
800  * Unregister driver from IUCV.
801  */
802 void iucv_unregister(struct iucv_handler *handler, int smp)
803 {
804 	struct iucv_path *p, *n;
805 
806 	mutex_lock(&iucv_register_mutex);
807 	spin_lock_bh(&iucv_table_lock);
808 	/* Remove handler from the iucv_handler_list. */
809 	list_del_init(&handler->list);
810 	/* Sever all pathids still refering to the handler. */
811 	list_for_each_entry_safe(p, n, &handler->paths, list) {
812 		iucv_sever_pathid(p->pathid, NULL);
813 		iucv_path_table[p->pathid] = NULL;
814 		list_del(&p->list);
815 		iucv_path_free(p);
816 	}
817 	spin_unlock_bh(&iucv_table_lock);
818 	if (!smp)
819 		iucv_nonsmp_handler--;
820 	if (list_empty(&iucv_handler_list))
821 		iucv_disable();
822 	else if (!smp && iucv_nonsmp_handler == 0)
823 		iucv_setmask_mp();
824 	mutex_unlock(&iucv_register_mutex);
825 }
826 EXPORT_SYMBOL(iucv_unregister);
827 
828 static int iucv_reboot_event(struct notifier_block *this,
829 			     unsigned long event, void *ptr)
830 {
831 	int i, rc;
832 
833 	get_online_cpus();
834 	on_each_cpu(iucv_block_cpu, NULL, 1);
835 	preempt_disable();
836 	for (i = 0; i < iucv_max_pathid; i++) {
837 		if (iucv_path_table[i])
838 			rc = iucv_sever_pathid(i, NULL);
839 	}
840 	preempt_enable();
841 	put_online_cpus();
842 	iucv_disable();
843 	return NOTIFY_DONE;
844 }
845 
846 static struct notifier_block iucv_reboot_notifier = {
847 	.notifier_call = iucv_reboot_event,
848 };
849 
850 /**
851  * iucv_path_accept
852  * @path: address of iucv path structure
853  * @handler: address of iucv handler structure
854  * @userdata: 16 bytes of data reflected to the communication partner
855  * @private: private data passed to interrupt handlers for this path
856  *
857  * This function is issued after the user received a connection pending
858  * external interrupt and now wishes to complete the IUCV communication path.
859  *
860  * Returns the result of the CP IUCV call.
861  */
862 int iucv_path_accept(struct iucv_path *path, struct iucv_handler *handler,
863 		     u8 userdata[16], void *private)
864 {
865 	union iucv_param *parm;
866 	int rc;
867 
868 	local_bh_disable();
869 	if (cpus_empty(iucv_buffer_cpumask)) {
870 		rc = -EIO;
871 		goto out;
872 	}
873 	/* Prepare parameter block. */
874 	parm = iucv_param[smp_processor_id()];
875 	memset(parm, 0, sizeof(union iucv_param));
876 	parm->ctrl.ippathid = path->pathid;
877 	parm->ctrl.ipmsglim = path->msglim;
878 	if (userdata)
879 		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
880 	parm->ctrl.ipflags1 = path->flags;
881 
882 	rc = iucv_call_b2f0(IUCV_ACCEPT, parm);
883 	if (!rc) {
884 		path->private = private;
885 		path->msglim = parm->ctrl.ipmsglim;
886 		path->flags = parm->ctrl.ipflags1;
887 	}
888 out:
889 	local_bh_enable();
890 	return rc;
891 }
892 EXPORT_SYMBOL(iucv_path_accept);
893 
894 /**
895  * iucv_path_connect
896  * @path: address of iucv path structure
897  * @handler: address of iucv handler structure
898  * @userid: 8-byte user identification
899  * @system: 8-byte target system identification
900  * @userdata: 16 bytes of data reflected to the communication partner
901  * @private: private data passed to interrupt handlers for this path
902  *
903  * This function establishes an IUCV path. Although the connect may complete
904  * successfully, you are not able to use the path until you receive an IUCV
905  * Connection Complete external interrupt.
906  *
907  * Returns the result of the CP IUCV call.
908  */
909 int iucv_path_connect(struct iucv_path *path, struct iucv_handler *handler,
910 		      u8 userid[8], u8 system[8], u8 userdata[16],
911 		      void *private)
912 {
913 	union iucv_param *parm;
914 	int rc;
915 
916 	spin_lock_bh(&iucv_table_lock);
917 	iucv_cleanup_queue();
918 	if (cpus_empty(iucv_buffer_cpumask)) {
919 		rc = -EIO;
920 		goto out;
921 	}
922 	parm = iucv_param[smp_processor_id()];
923 	memset(parm, 0, sizeof(union iucv_param));
924 	parm->ctrl.ipmsglim = path->msglim;
925 	parm->ctrl.ipflags1 = path->flags;
926 	if (userid) {
927 		memcpy(parm->ctrl.ipvmid, userid, sizeof(parm->ctrl.ipvmid));
928 		ASCEBC(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
929 		EBC_TOUPPER(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
930 	}
931 	if (system) {
932 		memcpy(parm->ctrl.iptarget, system,
933 		       sizeof(parm->ctrl.iptarget));
934 		ASCEBC(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
935 		EBC_TOUPPER(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
936 	}
937 	if (userdata)
938 		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
939 
940 	rc = iucv_call_b2f0(IUCV_CONNECT, parm);
941 	if (!rc) {
942 		if (parm->ctrl.ippathid < iucv_max_pathid) {
943 			path->pathid = parm->ctrl.ippathid;
944 			path->msglim = parm->ctrl.ipmsglim;
945 			path->flags = parm->ctrl.ipflags1;
946 			path->handler = handler;
947 			path->private = private;
948 			list_add_tail(&path->list, &handler->paths);
949 			iucv_path_table[path->pathid] = path;
950 		} else {
951 			iucv_sever_pathid(parm->ctrl.ippathid,
952 					  iucv_error_pathid);
953 			rc = -EIO;
954 		}
955 	}
956 out:
957 	spin_unlock_bh(&iucv_table_lock);
958 	return rc;
959 }
960 EXPORT_SYMBOL(iucv_path_connect);
961 
962 /**
963  * iucv_path_quiesce:
964  * @path: address of iucv path structure
965  * @userdata: 16 bytes of data reflected to the communication partner
966  *
967  * This function temporarily suspends incoming messages on an IUCV path.
968  * You can later reactivate the path by invoking the iucv_resume function.
969  *
970  * Returns the result from the CP IUCV call.
971  */
972 int iucv_path_quiesce(struct iucv_path *path, u8 userdata[16])
973 {
974 	union iucv_param *parm;
975 	int rc;
976 
977 	local_bh_disable();
978 	if (cpus_empty(iucv_buffer_cpumask)) {
979 		rc = -EIO;
980 		goto out;
981 	}
982 	parm = iucv_param[smp_processor_id()];
983 	memset(parm, 0, sizeof(union iucv_param));
984 	if (userdata)
985 		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
986 	parm->ctrl.ippathid = path->pathid;
987 	rc = iucv_call_b2f0(IUCV_QUIESCE, parm);
988 out:
989 	local_bh_enable();
990 	return rc;
991 }
992 EXPORT_SYMBOL(iucv_path_quiesce);
993 
994 /**
995  * iucv_path_resume:
996  * @path: address of iucv path structure
997  * @userdata: 16 bytes of data reflected to the communication partner
998  *
999  * This function resumes incoming messages on an IUCV path that has
1000  * been stopped with iucv_path_quiesce.
1001  *
1002  * Returns the result from the CP IUCV call.
1003  */
1004 int iucv_path_resume(struct iucv_path *path, u8 userdata[16])
1005 {
1006 	union iucv_param *parm;
1007 	int rc;
1008 
1009 	local_bh_disable();
1010 	if (cpus_empty(iucv_buffer_cpumask)) {
1011 		rc = -EIO;
1012 		goto out;
1013 	}
1014 	parm = iucv_param[smp_processor_id()];
1015 	memset(parm, 0, sizeof(union iucv_param));
1016 	if (userdata)
1017 		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
1018 	parm->ctrl.ippathid = path->pathid;
1019 	rc = iucv_call_b2f0(IUCV_RESUME, parm);
1020 out:
1021 	local_bh_enable();
1022 	return rc;
1023 }
1024 
1025 /**
1026  * iucv_path_sever
1027  * @path: address of iucv path structure
1028  * @userdata: 16 bytes of data reflected to the communication partner
1029  *
1030  * This function terminates an IUCV path.
1031  *
1032  * Returns the result from the CP IUCV call.
1033  */
1034 int iucv_path_sever(struct iucv_path *path, u8 userdata[16])
1035 {
1036 	int rc;
1037 
1038 	preempt_disable();
1039 	if (cpus_empty(iucv_buffer_cpumask)) {
1040 		rc = -EIO;
1041 		goto out;
1042 	}
1043 	if (iucv_active_cpu != smp_processor_id())
1044 		spin_lock_bh(&iucv_table_lock);
1045 	rc = iucv_sever_pathid(path->pathid, userdata);
1046 	iucv_path_table[path->pathid] = NULL;
1047 	list_del_init(&path->list);
1048 	if (iucv_active_cpu != smp_processor_id())
1049 		spin_unlock_bh(&iucv_table_lock);
1050 out:
1051 	preempt_enable();
1052 	return rc;
1053 }
1054 EXPORT_SYMBOL(iucv_path_sever);
1055 
1056 /**
1057  * iucv_message_purge
1058  * @path: address of iucv path structure
1059  * @msg: address of iucv msg structure
1060  * @srccls: source class of message
1061  *
1062  * Cancels a message you have sent.
1063  *
1064  * Returns the result from the CP IUCV call.
1065  */
1066 int iucv_message_purge(struct iucv_path *path, struct iucv_message *msg,
1067 		       u32 srccls)
1068 {
1069 	union iucv_param *parm;
1070 	int rc;
1071 
1072 	local_bh_disable();
1073 	if (cpus_empty(iucv_buffer_cpumask)) {
1074 		rc = -EIO;
1075 		goto out;
1076 	}
1077 	parm = iucv_param[smp_processor_id()];
1078 	memset(parm, 0, sizeof(union iucv_param));
1079 	parm->purge.ippathid = path->pathid;
1080 	parm->purge.ipmsgid = msg->id;
1081 	parm->purge.ipsrccls = srccls;
1082 	parm->purge.ipflags1 = IUCV_IPSRCCLS | IUCV_IPFGMID | IUCV_IPFGPID;
1083 	rc = iucv_call_b2f0(IUCV_PURGE, parm);
1084 	if (!rc) {
1085 		msg->audit = (*(u32 *) &parm->purge.ipaudit) >> 8;
1086 		msg->tag = parm->purge.ipmsgtag;
1087 	}
1088 out:
1089 	local_bh_enable();
1090 	return rc;
1091 }
1092 EXPORT_SYMBOL(iucv_message_purge);
1093 
1094 /**
1095  * iucv_message_receive_iprmdata
1096  * @path: address of iucv path structure
1097  * @msg: address of iucv msg structure
1098  * @flags: how the message is received (IUCV_IPBUFLST)
1099  * @buffer: address of data buffer or address of struct iucv_array
1100  * @size: length of data buffer
1101  * @residual:
1102  *
1103  * Internal function used by iucv_message_receive and __iucv_message_receive
1104  * to receive RMDATA data stored in struct iucv_message.
1105  */
1106 static int iucv_message_receive_iprmdata(struct iucv_path *path,
1107 					 struct iucv_message *msg,
1108 					 u8 flags, void *buffer,
1109 					 size_t size, size_t *residual)
1110 {
1111 	struct iucv_array *array;
1112 	u8 *rmmsg;
1113 	size_t copy;
1114 
1115 	/*
1116 	 * Message is 8 bytes long and has been stored to the
1117 	 * message descriptor itself.
1118 	 */
1119 	if (residual)
1120 		*residual = abs(size - 8);
1121 	rmmsg = msg->rmmsg;
1122 	if (flags & IUCV_IPBUFLST) {
1123 		/* Copy to struct iucv_array. */
1124 		size = (size < 8) ? size : 8;
1125 		for (array = buffer; size > 0; array++) {
1126 			copy = min_t(size_t, size, array->length);
1127 			memcpy((u8 *)(addr_t) array->address,
1128 				rmmsg, copy);
1129 			rmmsg += copy;
1130 			size -= copy;
1131 		}
1132 	} else {
1133 		/* Copy to direct buffer. */
1134 		memcpy(buffer, rmmsg, min_t(size_t, size, 8));
1135 	}
1136 	return 0;
1137 }
1138 
1139 /**
1140  * __iucv_message_receive
1141  * @path: address of iucv path structure
1142  * @msg: address of iucv msg structure
1143  * @flags: how the message is received (IUCV_IPBUFLST)
1144  * @buffer: address of data buffer or address of struct iucv_array
1145  * @size: length of data buffer
1146  * @residual:
1147  *
1148  * This function receives messages that are being sent to you over
1149  * established paths. This function will deal with RMDATA messages
1150  * embedded in struct iucv_message as well.
1151  *
1152  * Locking:	no locking
1153  *
1154  * Returns the result from the CP IUCV call.
1155  */
1156 int __iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
1157 			   u8 flags, void *buffer, size_t size, size_t *residual)
1158 {
1159 	union iucv_param *parm;
1160 	int rc;
1161 
1162 	if (msg->flags & IUCV_IPRMDATA)
1163 		return iucv_message_receive_iprmdata(path, msg, flags,
1164 						     buffer, size, residual);
1165 	if (cpus_empty(iucv_buffer_cpumask)) {
1166 		rc = -EIO;
1167 		goto out;
1168 	}
1169 	parm = iucv_param[smp_processor_id()];
1170 	memset(parm, 0, sizeof(union iucv_param));
1171 	parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1172 	parm->db.ipbfln1f = (u32) size;
1173 	parm->db.ipmsgid = msg->id;
1174 	parm->db.ippathid = path->pathid;
1175 	parm->db.iptrgcls = msg->class;
1176 	parm->db.ipflags1 = (flags | IUCV_IPFGPID |
1177 			     IUCV_IPFGMID | IUCV_IPTRGCLS);
1178 	rc = iucv_call_b2f0(IUCV_RECEIVE, parm);
1179 	if (!rc || rc == 5) {
1180 		msg->flags = parm->db.ipflags1;
1181 		if (residual)
1182 			*residual = parm->db.ipbfln1f;
1183 	}
1184 out:
1185 	return rc;
1186 }
1187 EXPORT_SYMBOL(__iucv_message_receive);
1188 
1189 /**
1190  * iucv_message_receive
1191  * @path: address of iucv path structure
1192  * @msg: address of iucv msg structure
1193  * @flags: how the message is received (IUCV_IPBUFLST)
1194  * @buffer: address of data buffer or address of struct iucv_array
1195  * @size: length of data buffer
1196  * @residual:
1197  *
1198  * This function receives messages that are being sent to you over
1199  * established paths. This function will deal with RMDATA messages
1200  * embedded in struct iucv_message as well.
1201  *
1202  * Locking:	local_bh_enable/local_bh_disable
1203  *
1204  * Returns the result from the CP IUCV call.
1205  */
1206 int iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
1207 			 u8 flags, void *buffer, size_t size, size_t *residual)
1208 {
1209 	int rc;
1210 
1211 	if (msg->flags & IUCV_IPRMDATA)
1212 		return iucv_message_receive_iprmdata(path, msg, flags,
1213 						     buffer, size, residual);
1214 	local_bh_disable();
1215 	rc = __iucv_message_receive(path, msg, flags, buffer, size, residual);
1216 	local_bh_enable();
1217 	return rc;
1218 }
1219 EXPORT_SYMBOL(iucv_message_receive);
1220 
1221 /**
1222  * iucv_message_reject
1223  * @path: address of iucv path structure
1224  * @msg: address of iucv msg structure
1225  *
1226  * The reject function refuses a specified message. Between the time you
1227  * are notified of a message and the time that you complete the message,
1228  * the message may be rejected.
1229  *
1230  * Returns the result from the CP IUCV call.
1231  */
1232 int iucv_message_reject(struct iucv_path *path, struct iucv_message *msg)
1233 {
1234 	union iucv_param *parm;
1235 	int rc;
1236 
1237 	local_bh_disable();
1238 	if (cpus_empty(iucv_buffer_cpumask)) {
1239 		rc = -EIO;
1240 		goto out;
1241 	}
1242 	parm = iucv_param[smp_processor_id()];
1243 	memset(parm, 0, sizeof(union iucv_param));
1244 	parm->db.ippathid = path->pathid;
1245 	parm->db.ipmsgid = msg->id;
1246 	parm->db.iptrgcls = msg->class;
1247 	parm->db.ipflags1 = (IUCV_IPTRGCLS | IUCV_IPFGMID | IUCV_IPFGPID);
1248 	rc = iucv_call_b2f0(IUCV_REJECT, parm);
1249 out:
1250 	local_bh_enable();
1251 	return rc;
1252 }
1253 EXPORT_SYMBOL(iucv_message_reject);
1254 
1255 /**
1256  * iucv_message_reply
1257  * @path: address of iucv path structure
1258  * @msg: address of iucv msg structure
1259  * @flags: how the reply is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1260  * @reply: address of reply data buffer or address of struct iucv_array
1261  * @size: length of reply data buffer
1262  *
1263  * This function responds to the two-way messages that you receive. You
1264  * must identify completely the message to which you wish to reply. ie,
1265  * pathid, msgid, and trgcls. Prmmsg signifies the data is moved into
1266  * the parameter list.
1267  *
1268  * Returns the result from the CP IUCV call.
1269  */
1270 int iucv_message_reply(struct iucv_path *path, struct iucv_message *msg,
1271 		       u8 flags, void *reply, size_t size)
1272 {
1273 	union iucv_param *parm;
1274 	int rc;
1275 
1276 	local_bh_disable();
1277 	if (cpus_empty(iucv_buffer_cpumask)) {
1278 		rc = -EIO;
1279 		goto out;
1280 	}
1281 	parm = iucv_param[smp_processor_id()];
1282 	memset(parm, 0, sizeof(union iucv_param));
1283 	if (flags & IUCV_IPRMDATA) {
1284 		parm->dpl.ippathid = path->pathid;
1285 		parm->dpl.ipflags1 = flags;
1286 		parm->dpl.ipmsgid = msg->id;
1287 		parm->dpl.iptrgcls = msg->class;
1288 		memcpy(parm->dpl.iprmmsg, reply, min_t(size_t, size, 8));
1289 	} else {
1290 		parm->db.ipbfadr1 = (u32)(addr_t) reply;
1291 		parm->db.ipbfln1f = (u32) size;
1292 		parm->db.ippathid = path->pathid;
1293 		parm->db.ipflags1 = flags;
1294 		parm->db.ipmsgid = msg->id;
1295 		parm->db.iptrgcls = msg->class;
1296 	}
1297 	rc = iucv_call_b2f0(IUCV_REPLY, parm);
1298 out:
1299 	local_bh_enable();
1300 	return rc;
1301 }
1302 EXPORT_SYMBOL(iucv_message_reply);
1303 
1304 /**
1305  * __iucv_message_send
1306  * @path: address of iucv path structure
1307  * @msg: address of iucv msg structure
1308  * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1309  * @srccls: source class of message
1310  * @buffer: address of send buffer or address of struct iucv_array
1311  * @size: length of send buffer
1312  *
1313  * This function transmits data to another application. Data to be
1314  * transmitted is in a buffer and this is a one-way message and the
1315  * receiver will not reply to the message.
1316  *
1317  * Locking:	no locking
1318  *
1319  * Returns the result from the CP IUCV call.
1320  */
1321 int __iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
1322 		      u8 flags, u32 srccls, void *buffer, size_t size)
1323 {
1324 	union iucv_param *parm;
1325 	int rc;
1326 
1327 	if (cpus_empty(iucv_buffer_cpumask)) {
1328 		rc = -EIO;
1329 		goto out;
1330 	}
1331 	parm = iucv_param[smp_processor_id()];
1332 	memset(parm, 0, sizeof(union iucv_param));
1333 	if (flags & IUCV_IPRMDATA) {
1334 		/* Message of 8 bytes can be placed into the parameter list. */
1335 		parm->dpl.ippathid = path->pathid;
1336 		parm->dpl.ipflags1 = flags | IUCV_IPNORPY;
1337 		parm->dpl.iptrgcls = msg->class;
1338 		parm->dpl.ipsrccls = srccls;
1339 		parm->dpl.ipmsgtag = msg->tag;
1340 		memcpy(parm->dpl.iprmmsg, buffer, 8);
1341 	} else {
1342 		parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1343 		parm->db.ipbfln1f = (u32) size;
1344 		parm->db.ippathid = path->pathid;
1345 		parm->db.ipflags1 = flags | IUCV_IPNORPY;
1346 		parm->db.iptrgcls = msg->class;
1347 		parm->db.ipsrccls = srccls;
1348 		parm->db.ipmsgtag = msg->tag;
1349 	}
1350 	rc = iucv_call_b2f0(IUCV_SEND, parm);
1351 	if (!rc)
1352 		msg->id = parm->db.ipmsgid;
1353 out:
1354 	return rc;
1355 }
1356 EXPORT_SYMBOL(__iucv_message_send);
1357 
1358 /**
1359  * iucv_message_send
1360  * @path: address of iucv path structure
1361  * @msg: address of iucv msg structure
1362  * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1363  * @srccls: source class of message
1364  * @buffer: address of send buffer or address of struct iucv_array
1365  * @size: length of send buffer
1366  *
1367  * This function transmits data to another application. Data to be
1368  * transmitted is in a buffer and this is a one-way message and the
1369  * receiver will not reply to the message.
1370  *
1371  * Locking:	local_bh_enable/local_bh_disable
1372  *
1373  * Returns the result from the CP IUCV call.
1374  */
1375 int iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
1376 		      u8 flags, u32 srccls, void *buffer, size_t size)
1377 {
1378 	int rc;
1379 
1380 	local_bh_disable();
1381 	rc = __iucv_message_send(path, msg, flags, srccls, buffer, size);
1382 	local_bh_enable();
1383 	return rc;
1384 }
1385 EXPORT_SYMBOL(iucv_message_send);
1386 
1387 /**
1388  * iucv_message_send2way
1389  * @path: address of iucv path structure
1390  * @msg: address of iucv msg structure
1391  * @flags: how the message is sent and the reply is received
1392  *	   (IUCV_IPRMDATA, IUCV_IPBUFLST, IUCV_IPPRTY, IUCV_ANSLST)
1393  * @srccls: source class of message
1394  * @buffer: address of send buffer or address of struct iucv_array
1395  * @size: length of send buffer
1396  * @ansbuf: address of answer buffer or address of struct iucv_array
1397  * @asize: size of reply buffer
1398  *
1399  * This function transmits data to another application. Data to be
1400  * transmitted is in a buffer. The receiver of the send is expected to
1401  * reply to the message and a buffer is provided into which IUCV moves
1402  * the reply to this message.
1403  *
1404  * Returns the result from the CP IUCV call.
1405  */
1406 int iucv_message_send2way(struct iucv_path *path, struct iucv_message *msg,
1407 			  u8 flags, u32 srccls, void *buffer, size_t size,
1408 			  void *answer, size_t asize, size_t *residual)
1409 {
1410 	union iucv_param *parm;
1411 	int rc;
1412 
1413 	local_bh_disable();
1414 	if (cpus_empty(iucv_buffer_cpumask)) {
1415 		rc = -EIO;
1416 		goto out;
1417 	}
1418 	parm = iucv_param[smp_processor_id()];
1419 	memset(parm, 0, sizeof(union iucv_param));
1420 	if (flags & IUCV_IPRMDATA) {
1421 		parm->dpl.ippathid = path->pathid;
1422 		parm->dpl.ipflags1 = path->flags;	/* priority message */
1423 		parm->dpl.iptrgcls = msg->class;
1424 		parm->dpl.ipsrccls = srccls;
1425 		parm->dpl.ipmsgtag = msg->tag;
1426 		parm->dpl.ipbfadr2 = (u32)(addr_t) answer;
1427 		parm->dpl.ipbfln2f = (u32) asize;
1428 		memcpy(parm->dpl.iprmmsg, buffer, 8);
1429 	} else {
1430 		parm->db.ippathid = path->pathid;
1431 		parm->db.ipflags1 = path->flags;	/* priority message */
1432 		parm->db.iptrgcls = msg->class;
1433 		parm->db.ipsrccls = srccls;
1434 		parm->db.ipmsgtag = msg->tag;
1435 		parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1436 		parm->db.ipbfln1f = (u32) size;
1437 		parm->db.ipbfadr2 = (u32)(addr_t) answer;
1438 		parm->db.ipbfln2f = (u32) asize;
1439 	}
1440 	rc = iucv_call_b2f0(IUCV_SEND, parm);
1441 	if (!rc)
1442 		msg->id = parm->db.ipmsgid;
1443 out:
1444 	local_bh_enable();
1445 	return rc;
1446 }
1447 EXPORT_SYMBOL(iucv_message_send2way);
1448 
1449 /**
1450  * iucv_path_pending
1451  * @data: Pointer to external interrupt buffer
1452  *
1453  * Process connection pending work item. Called from tasklet while holding
1454  * iucv_table_lock.
1455  */
1456 struct iucv_path_pending {
1457 	u16 ippathid;
1458 	u8  ipflags1;
1459 	u8  iptype;
1460 	u16 ipmsglim;
1461 	u16 res1;
1462 	u8  ipvmid[8];
1463 	u8  ipuser[16];
1464 	u32 res3;
1465 	u8  ippollfg;
1466 	u8  res4[3];
1467 } __packed;
1468 
1469 static void iucv_path_pending(struct iucv_irq_data *data)
1470 {
1471 	struct iucv_path_pending *ipp = (void *) data;
1472 	struct iucv_handler *handler;
1473 	struct iucv_path *path;
1474 	char *error;
1475 
1476 	BUG_ON(iucv_path_table[ipp->ippathid]);
1477 	/* New pathid, handler found. Create a new path struct. */
1478 	error = iucv_error_no_memory;
1479 	path = iucv_path_alloc(ipp->ipmsglim, ipp->ipflags1, GFP_ATOMIC);
1480 	if (!path)
1481 		goto out_sever;
1482 	path->pathid = ipp->ippathid;
1483 	iucv_path_table[path->pathid] = path;
1484 	EBCASC(ipp->ipvmid, 8);
1485 
1486 	/* Call registered handler until one is found that wants the path. */
1487 	list_for_each_entry(handler, &iucv_handler_list, list) {
1488 		if (!handler->path_pending)
1489 			continue;
1490 		/*
1491 		 * Add path to handler to allow a call to iucv_path_sever
1492 		 * inside the path_pending function. If the handler returns
1493 		 * an error remove the path from the handler again.
1494 		 */
1495 		list_add(&path->list, &handler->paths);
1496 		path->handler = handler;
1497 		if (!handler->path_pending(path, ipp->ipvmid, ipp->ipuser))
1498 			return;
1499 		list_del(&path->list);
1500 		path->handler = NULL;
1501 	}
1502 	/* No handler wanted the path. */
1503 	iucv_path_table[path->pathid] = NULL;
1504 	iucv_path_free(path);
1505 	error = iucv_error_no_listener;
1506 out_sever:
1507 	iucv_sever_pathid(ipp->ippathid, error);
1508 }
1509 
1510 /**
1511  * iucv_path_complete
1512  * @data: Pointer to external interrupt buffer
1513  *
1514  * Process connection complete work item. Called from tasklet while holding
1515  * iucv_table_lock.
1516  */
1517 struct iucv_path_complete {
1518 	u16 ippathid;
1519 	u8  ipflags1;
1520 	u8  iptype;
1521 	u16 ipmsglim;
1522 	u16 res1;
1523 	u8  res2[8];
1524 	u8  ipuser[16];
1525 	u32 res3;
1526 	u8  ippollfg;
1527 	u8  res4[3];
1528 } __packed;
1529 
1530 static void iucv_path_complete(struct iucv_irq_data *data)
1531 {
1532 	struct iucv_path_complete *ipc = (void *) data;
1533 	struct iucv_path *path = iucv_path_table[ipc->ippathid];
1534 
1535 	if (path)
1536 		path->flags = ipc->ipflags1;
1537 	if (path && path->handler && path->handler->path_complete)
1538 		path->handler->path_complete(path, ipc->ipuser);
1539 }
1540 
1541 /**
1542  * iucv_path_severed
1543  * @data: Pointer to external interrupt buffer
1544  *
1545  * Process connection severed work item. Called from tasklet while holding
1546  * iucv_table_lock.
1547  */
1548 struct iucv_path_severed {
1549 	u16 ippathid;
1550 	u8  res1;
1551 	u8  iptype;
1552 	u32 res2;
1553 	u8  res3[8];
1554 	u8  ipuser[16];
1555 	u32 res4;
1556 	u8  ippollfg;
1557 	u8  res5[3];
1558 } __packed;
1559 
1560 static void iucv_path_severed(struct iucv_irq_data *data)
1561 {
1562 	struct iucv_path_severed *ips = (void *) data;
1563 	struct iucv_path *path = iucv_path_table[ips->ippathid];
1564 
1565 	if (!path || !path->handler)	/* Already severed */
1566 		return;
1567 	if (path->handler->path_severed)
1568 		path->handler->path_severed(path, ips->ipuser);
1569 	else {
1570 		iucv_sever_pathid(path->pathid, NULL);
1571 		iucv_path_table[path->pathid] = NULL;
1572 		list_del(&path->list);
1573 		iucv_path_free(path);
1574 	}
1575 }
1576 
1577 /**
1578  * iucv_path_quiesced
1579  * @data: Pointer to external interrupt buffer
1580  *
1581  * Process connection quiesced work item. Called from tasklet while holding
1582  * iucv_table_lock.
1583  */
1584 struct iucv_path_quiesced {
1585 	u16 ippathid;
1586 	u8  res1;
1587 	u8  iptype;
1588 	u32 res2;
1589 	u8  res3[8];
1590 	u8  ipuser[16];
1591 	u32 res4;
1592 	u8  ippollfg;
1593 	u8  res5[3];
1594 } __packed;
1595 
1596 static void iucv_path_quiesced(struct iucv_irq_data *data)
1597 {
1598 	struct iucv_path_quiesced *ipq = (void *) data;
1599 	struct iucv_path *path = iucv_path_table[ipq->ippathid];
1600 
1601 	if (path && path->handler && path->handler->path_quiesced)
1602 		path->handler->path_quiesced(path, ipq->ipuser);
1603 }
1604 
1605 /**
1606  * iucv_path_resumed
1607  * @data: Pointer to external interrupt buffer
1608  *
1609  * Process connection resumed work item. Called from tasklet while holding
1610  * iucv_table_lock.
1611  */
1612 struct iucv_path_resumed {
1613 	u16 ippathid;
1614 	u8  res1;
1615 	u8  iptype;
1616 	u32 res2;
1617 	u8  res3[8];
1618 	u8  ipuser[16];
1619 	u32 res4;
1620 	u8  ippollfg;
1621 	u8  res5[3];
1622 } __packed;
1623 
1624 static void iucv_path_resumed(struct iucv_irq_data *data)
1625 {
1626 	struct iucv_path_resumed *ipr = (void *) data;
1627 	struct iucv_path *path = iucv_path_table[ipr->ippathid];
1628 
1629 	if (path && path->handler && path->handler->path_resumed)
1630 		path->handler->path_resumed(path, ipr->ipuser);
1631 }
1632 
1633 /**
1634  * iucv_message_complete
1635  * @data: Pointer to external interrupt buffer
1636  *
1637  * Process message complete work item. Called from tasklet while holding
1638  * iucv_table_lock.
1639  */
1640 struct iucv_message_complete {
1641 	u16 ippathid;
1642 	u8  ipflags1;
1643 	u8  iptype;
1644 	u32 ipmsgid;
1645 	u32 ipaudit;
1646 	u8  iprmmsg[8];
1647 	u32 ipsrccls;
1648 	u32 ipmsgtag;
1649 	u32 res;
1650 	u32 ipbfln2f;
1651 	u8  ippollfg;
1652 	u8  res2[3];
1653 } __packed;
1654 
1655 static void iucv_message_complete(struct iucv_irq_data *data)
1656 {
1657 	struct iucv_message_complete *imc = (void *) data;
1658 	struct iucv_path *path = iucv_path_table[imc->ippathid];
1659 	struct iucv_message msg;
1660 
1661 	if (path && path->handler && path->handler->message_complete) {
1662 		msg.flags = imc->ipflags1;
1663 		msg.id = imc->ipmsgid;
1664 		msg.audit = imc->ipaudit;
1665 		memcpy(msg.rmmsg, imc->iprmmsg, 8);
1666 		msg.class = imc->ipsrccls;
1667 		msg.tag = imc->ipmsgtag;
1668 		msg.length = imc->ipbfln2f;
1669 		path->handler->message_complete(path, &msg);
1670 	}
1671 }
1672 
1673 /**
1674  * iucv_message_pending
1675  * @data: Pointer to external interrupt buffer
1676  *
1677  * Process message pending work item. Called from tasklet while holding
1678  * iucv_table_lock.
1679  */
1680 struct iucv_message_pending {
1681 	u16 ippathid;
1682 	u8  ipflags1;
1683 	u8  iptype;
1684 	u32 ipmsgid;
1685 	u32 iptrgcls;
1686 	union {
1687 		u32 iprmmsg1_u32;
1688 		u8  iprmmsg1[4];
1689 	} ln1msg1;
1690 	union {
1691 		u32 ipbfln1f;
1692 		u8  iprmmsg2[4];
1693 	} ln1msg2;
1694 	u32 res1[3];
1695 	u32 ipbfln2f;
1696 	u8  ippollfg;
1697 	u8  res2[3];
1698 } __packed;
1699 
1700 static void iucv_message_pending(struct iucv_irq_data *data)
1701 {
1702 	struct iucv_message_pending *imp = (void *) data;
1703 	struct iucv_path *path = iucv_path_table[imp->ippathid];
1704 	struct iucv_message msg;
1705 
1706 	if (path && path->handler && path->handler->message_pending) {
1707 		msg.flags = imp->ipflags1;
1708 		msg.id = imp->ipmsgid;
1709 		msg.class = imp->iptrgcls;
1710 		if (imp->ipflags1 & IUCV_IPRMDATA) {
1711 			memcpy(msg.rmmsg, imp->ln1msg1.iprmmsg1, 8);
1712 			msg.length = 8;
1713 		} else
1714 			msg.length = imp->ln1msg2.ipbfln1f;
1715 		msg.reply_size = imp->ipbfln2f;
1716 		path->handler->message_pending(path, &msg);
1717 	}
1718 }
1719 
1720 /**
1721  * iucv_tasklet_fn:
1722  *
1723  * This tasklet loops over the queue of irq buffers created by
1724  * iucv_external_interrupt, calls the appropriate action handler
1725  * and then frees the buffer.
1726  */
1727 static void iucv_tasklet_fn(unsigned long ignored)
1728 {
1729 	typedef void iucv_irq_fn(struct iucv_irq_data *);
1730 	static iucv_irq_fn *irq_fn[] = {
1731 		[0x02] = iucv_path_complete,
1732 		[0x03] = iucv_path_severed,
1733 		[0x04] = iucv_path_quiesced,
1734 		[0x05] = iucv_path_resumed,
1735 		[0x06] = iucv_message_complete,
1736 		[0x07] = iucv_message_complete,
1737 		[0x08] = iucv_message_pending,
1738 		[0x09] = iucv_message_pending,
1739 	};
1740 	LIST_HEAD(task_queue);
1741 	struct iucv_irq_list *p, *n;
1742 
1743 	/* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1744 	if (!spin_trylock(&iucv_table_lock)) {
1745 		tasklet_schedule(&iucv_tasklet);
1746 		return;
1747 	}
1748 	iucv_active_cpu = smp_processor_id();
1749 
1750 	spin_lock_irq(&iucv_queue_lock);
1751 	list_splice_init(&iucv_task_queue, &task_queue);
1752 	spin_unlock_irq(&iucv_queue_lock);
1753 
1754 	list_for_each_entry_safe(p, n, &task_queue, list) {
1755 		list_del_init(&p->list);
1756 		irq_fn[p->data.iptype](&p->data);
1757 		kfree(p);
1758 	}
1759 
1760 	iucv_active_cpu = -1;
1761 	spin_unlock(&iucv_table_lock);
1762 }
1763 
1764 /**
1765  * iucv_work_fn:
1766  *
1767  * This work function loops over the queue of path pending irq blocks
1768  * created by iucv_external_interrupt, calls the appropriate action
1769  * handler and then frees the buffer.
1770  */
1771 static void iucv_work_fn(struct work_struct *work)
1772 {
1773 	LIST_HEAD(work_queue);
1774 	struct iucv_irq_list *p, *n;
1775 
1776 	/* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1777 	spin_lock_bh(&iucv_table_lock);
1778 	iucv_active_cpu = smp_processor_id();
1779 
1780 	spin_lock_irq(&iucv_queue_lock);
1781 	list_splice_init(&iucv_work_queue, &work_queue);
1782 	spin_unlock_irq(&iucv_queue_lock);
1783 
1784 	iucv_cleanup_queue();
1785 	list_for_each_entry_safe(p, n, &work_queue, list) {
1786 		list_del_init(&p->list);
1787 		iucv_path_pending(&p->data);
1788 		kfree(p);
1789 	}
1790 
1791 	iucv_active_cpu = -1;
1792 	spin_unlock_bh(&iucv_table_lock);
1793 }
1794 
1795 /**
1796  * iucv_external_interrupt
1797  * @code: irq code
1798  *
1799  * Handles external interrupts coming in from CP.
1800  * Places the interrupt buffer on a queue and schedules iucv_tasklet_fn().
1801  */
1802 static void iucv_external_interrupt(unsigned int ext_int_code,
1803 				    unsigned int param32, unsigned long param64)
1804 {
1805 	struct iucv_irq_data *p;
1806 	struct iucv_irq_list *work;
1807 
1808 	kstat_cpu(smp_processor_id()).irqs[EXTINT_IUC]++;
1809 	p = iucv_irq_data[smp_processor_id()];
1810 	if (p->ippathid >= iucv_max_pathid) {
1811 		WARN_ON(p->ippathid >= iucv_max_pathid);
1812 		iucv_sever_pathid(p->ippathid, iucv_error_no_listener);
1813 		return;
1814 	}
1815 	BUG_ON(p->iptype  < 0x01 || p->iptype > 0x09);
1816 	work = kmalloc(sizeof(struct iucv_irq_list), GFP_ATOMIC);
1817 	if (!work) {
1818 		pr_warning("iucv_external_interrupt: out of memory\n");
1819 		return;
1820 	}
1821 	memcpy(&work->data, p, sizeof(work->data));
1822 	spin_lock(&iucv_queue_lock);
1823 	if (p->iptype == 0x01) {
1824 		/* Path pending interrupt. */
1825 		list_add_tail(&work->list, &iucv_work_queue);
1826 		schedule_work(&iucv_work);
1827 	} else {
1828 		/* The other interrupts. */
1829 		list_add_tail(&work->list, &iucv_task_queue);
1830 		tasklet_schedule(&iucv_tasklet);
1831 	}
1832 	spin_unlock(&iucv_queue_lock);
1833 }
1834 
1835 static int iucv_pm_prepare(struct device *dev)
1836 {
1837 	int rc = 0;
1838 
1839 #ifdef CONFIG_PM_DEBUG
1840 	printk(KERN_INFO "iucv_pm_prepare\n");
1841 #endif
1842 	if (dev->driver && dev->driver->pm && dev->driver->pm->prepare)
1843 		rc = dev->driver->pm->prepare(dev);
1844 	return rc;
1845 }
1846 
1847 static void iucv_pm_complete(struct device *dev)
1848 {
1849 #ifdef CONFIG_PM_DEBUG
1850 	printk(KERN_INFO "iucv_pm_complete\n");
1851 #endif
1852 	if (dev->driver && dev->driver->pm && dev->driver->pm->complete)
1853 		dev->driver->pm->complete(dev);
1854 }
1855 
1856 /**
1857  * iucv_path_table_empty() - determine if iucv path table is empty
1858  *
1859  * Returns 0 if there are still iucv pathes defined
1860  *	   1 if there are no iucv pathes defined
1861  */
1862 int iucv_path_table_empty(void)
1863 {
1864 	int i;
1865 
1866 	for (i = 0; i < iucv_max_pathid; i++) {
1867 		if (iucv_path_table[i])
1868 			return 0;
1869 	}
1870 	return 1;
1871 }
1872 
1873 /**
1874  * iucv_pm_freeze() - Freeze PM callback
1875  * @dev:	iucv-based device
1876  *
1877  * disable iucv interrupts
1878  * invoke callback function of the iucv-based driver
1879  * shut down iucv, if no iucv-pathes are established anymore
1880  */
1881 static int iucv_pm_freeze(struct device *dev)
1882 {
1883 	int cpu;
1884 	struct iucv_irq_list *p, *n;
1885 	int rc = 0;
1886 
1887 #ifdef CONFIG_PM_DEBUG
1888 	printk(KERN_WARNING "iucv_pm_freeze\n");
1889 #endif
1890 	if (iucv_pm_state != IUCV_PM_FREEZING) {
1891 		for_each_cpu_mask_nr(cpu, iucv_irq_cpumask)
1892 			smp_call_function_single(cpu, iucv_block_cpu_almost,
1893 						 NULL, 1);
1894 		cancel_work_sync(&iucv_work);
1895 		list_for_each_entry_safe(p, n, &iucv_work_queue, list) {
1896 			list_del_init(&p->list);
1897 			iucv_sever_pathid(p->data.ippathid,
1898 					  iucv_error_no_listener);
1899 			kfree(p);
1900 		}
1901 	}
1902 	iucv_pm_state = IUCV_PM_FREEZING;
1903 	if (dev->driver && dev->driver->pm && dev->driver->pm->freeze)
1904 		rc = dev->driver->pm->freeze(dev);
1905 	if (iucv_path_table_empty())
1906 		iucv_disable();
1907 	return rc;
1908 }
1909 
1910 /**
1911  * iucv_pm_thaw() - Thaw PM callback
1912  * @dev:	iucv-based device
1913  *
1914  * make iucv ready for use again: allocate path table, declare interrupt buffers
1915  *				  and enable iucv interrupts
1916  * invoke callback function of the iucv-based driver
1917  */
1918 static int iucv_pm_thaw(struct device *dev)
1919 {
1920 	int rc = 0;
1921 
1922 #ifdef CONFIG_PM_DEBUG
1923 	printk(KERN_WARNING "iucv_pm_thaw\n");
1924 #endif
1925 	iucv_pm_state = IUCV_PM_THAWING;
1926 	if (!iucv_path_table) {
1927 		rc = iucv_enable();
1928 		if (rc)
1929 			goto out;
1930 	}
1931 	if (cpus_empty(iucv_irq_cpumask)) {
1932 		if (iucv_nonsmp_handler)
1933 			/* enable interrupts on one cpu */
1934 			iucv_allow_cpu(NULL);
1935 		else
1936 			/* enable interrupts on all cpus */
1937 			iucv_setmask_mp();
1938 	}
1939 	if (dev->driver && dev->driver->pm && dev->driver->pm->thaw)
1940 		rc = dev->driver->pm->thaw(dev);
1941 out:
1942 	return rc;
1943 }
1944 
1945 /**
1946  * iucv_pm_restore() - Restore PM callback
1947  * @dev:	iucv-based device
1948  *
1949  * make iucv ready for use again: allocate path table, declare interrupt buffers
1950  *				  and enable iucv interrupts
1951  * invoke callback function of the iucv-based driver
1952  */
1953 static int iucv_pm_restore(struct device *dev)
1954 {
1955 	int rc = 0;
1956 
1957 #ifdef CONFIG_PM_DEBUG
1958 	printk(KERN_WARNING "iucv_pm_restore %p\n", iucv_path_table);
1959 #endif
1960 	if ((iucv_pm_state != IUCV_PM_RESTORING) && iucv_path_table)
1961 		pr_warning("Suspending Linux did not completely close all IUCV "
1962 			"connections\n");
1963 	iucv_pm_state = IUCV_PM_RESTORING;
1964 	if (cpus_empty(iucv_irq_cpumask)) {
1965 		rc = iucv_query_maxconn();
1966 		rc = iucv_enable();
1967 		if (rc)
1968 			goto out;
1969 	}
1970 	if (dev->driver && dev->driver->pm && dev->driver->pm->restore)
1971 		rc = dev->driver->pm->restore(dev);
1972 out:
1973 	return rc;
1974 }
1975 
1976 /**
1977  * iucv_init
1978  *
1979  * Allocates and initializes various data structures.
1980  */
1981 static int __init iucv_init(void)
1982 {
1983 	int rc;
1984 	int cpu;
1985 
1986 	if (!MACHINE_IS_VM) {
1987 		rc = -EPROTONOSUPPORT;
1988 		goto out;
1989 	}
1990 	rc = iucv_query_maxconn();
1991 	if (rc)
1992 		goto out;
1993 	rc = register_external_interrupt(0x4000, iucv_external_interrupt);
1994 	if (rc)
1995 		goto out;
1996 	iucv_root = root_device_register("iucv");
1997 	if (IS_ERR(iucv_root)) {
1998 		rc = PTR_ERR(iucv_root);
1999 		goto out_int;
2000 	}
2001 
2002 	for_each_online_cpu(cpu) {
2003 		/* Note: GFP_DMA used to get memory below 2G */
2004 		iucv_irq_data[cpu] = kmalloc_node(sizeof(struct iucv_irq_data),
2005 				     GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
2006 		if (!iucv_irq_data[cpu]) {
2007 			rc = -ENOMEM;
2008 			goto out_free;
2009 		}
2010 
2011 		/* Allocate parameter blocks. */
2012 		iucv_param[cpu] = kmalloc_node(sizeof(union iucv_param),
2013 				  GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
2014 		if (!iucv_param[cpu]) {
2015 			rc = -ENOMEM;
2016 			goto out_free;
2017 		}
2018 		iucv_param_irq[cpu] = kmalloc_node(sizeof(union iucv_param),
2019 				  GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
2020 		if (!iucv_param_irq[cpu]) {
2021 			rc = -ENOMEM;
2022 			goto out_free;
2023 		}
2024 
2025 	}
2026 	rc = register_hotcpu_notifier(&iucv_cpu_notifier);
2027 	if (rc)
2028 		goto out_free;
2029 	rc = register_reboot_notifier(&iucv_reboot_notifier);
2030 	if (rc)
2031 		goto out_cpu;
2032 	ASCEBC(iucv_error_no_listener, 16);
2033 	ASCEBC(iucv_error_no_memory, 16);
2034 	ASCEBC(iucv_error_pathid, 16);
2035 	iucv_available = 1;
2036 	rc = bus_register(&iucv_bus);
2037 	if (rc)
2038 		goto out_reboot;
2039 	return 0;
2040 
2041 out_reboot:
2042 	unregister_reboot_notifier(&iucv_reboot_notifier);
2043 out_cpu:
2044 	unregister_hotcpu_notifier(&iucv_cpu_notifier);
2045 out_free:
2046 	for_each_possible_cpu(cpu) {
2047 		kfree(iucv_param_irq[cpu]);
2048 		iucv_param_irq[cpu] = NULL;
2049 		kfree(iucv_param[cpu]);
2050 		iucv_param[cpu] = NULL;
2051 		kfree(iucv_irq_data[cpu]);
2052 		iucv_irq_data[cpu] = NULL;
2053 	}
2054 	root_device_unregister(iucv_root);
2055 out_int:
2056 	unregister_external_interrupt(0x4000, iucv_external_interrupt);
2057 out:
2058 	return rc;
2059 }
2060 
2061 /**
2062  * iucv_exit
2063  *
2064  * Frees everything allocated from iucv_init.
2065  */
2066 static void __exit iucv_exit(void)
2067 {
2068 	struct iucv_irq_list *p, *n;
2069 	int cpu;
2070 
2071 	spin_lock_irq(&iucv_queue_lock);
2072 	list_for_each_entry_safe(p, n, &iucv_task_queue, list)
2073 		kfree(p);
2074 	list_for_each_entry_safe(p, n, &iucv_work_queue, list)
2075 		kfree(p);
2076 	spin_unlock_irq(&iucv_queue_lock);
2077 	unregister_reboot_notifier(&iucv_reboot_notifier);
2078 	unregister_hotcpu_notifier(&iucv_cpu_notifier);
2079 	for_each_possible_cpu(cpu) {
2080 		kfree(iucv_param_irq[cpu]);
2081 		iucv_param_irq[cpu] = NULL;
2082 		kfree(iucv_param[cpu]);
2083 		iucv_param[cpu] = NULL;
2084 		kfree(iucv_irq_data[cpu]);
2085 		iucv_irq_data[cpu] = NULL;
2086 	}
2087 	root_device_unregister(iucv_root);
2088 	bus_unregister(&iucv_bus);
2089 	unregister_external_interrupt(0x4000, iucv_external_interrupt);
2090 }
2091 
2092 subsys_initcall(iucv_init);
2093 module_exit(iucv_exit);
2094 
2095 MODULE_AUTHOR("(C) 2001 IBM Corp. by Fritz Elfert (felfert@millenux.com)");
2096 MODULE_DESCRIPTION("Linux for S/390 IUCV lowlevel driver");
2097 MODULE_LICENSE("GPL");
2098