xref: /kernel/linux/linux-6.6/net/iucv/iucv.c (revision 62306a36)
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * IUCV base infrastructure.
4 *
5 * Copyright IBM Corp. 2001, 2009
6 *
7 * Author(s):
8 *    Original source:
9 *	Alan Altmark (Alan_Altmark@us.ibm.com)	Sept. 2000
10 *	Xenia Tkatschow (xenia@us.ibm.com)
11 *    2Gb awareness and general cleanup:
12 *	Fritz Elfert (elfert@de.ibm.com, felfert@millenux.com)
13 *    Rewritten for af_iucv:
14 *	Martin Schwidefsky <schwidefsky@de.ibm.com>
15 *    PM functions:
16 *	Ursula Braun (ursula.braun@de.ibm.com)
17 *
18 * Documentation used:
19 *    The original source
20 *    CP Programming Service, IBM document # SC24-5760
21 */
22
23#define KMSG_COMPONENT "iucv"
24#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
25
26#include <linux/kernel_stat.h>
27#include <linux/module.h>
28#include <linux/moduleparam.h>
29#include <linux/spinlock.h>
30#include <linux/kernel.h>
31#include <linux/slab.h>
32#include <linux/init.h>
33#include <linux/interrupt.h>
34#include <linux/list.h>
35#include <linux/errno.h>
36#include <linux/err.h>
37#include <linux/device.h>
38#include <linux/cpu.h>
39#include <linux/reboot.h>
40#include <net/iucv/iucv.h>
41#include <linux/atomic.h>
42#include <asm/ebcdic.h>
43#include <asm/io.h>
44#include <asm/irq.h>
45#include <asm/smp.h>
46
47/*
48 * FLAGS:
49 * All flags are defined in the field IPFLAGS1 of each function
50 * and can be found in CP Programming Services.
51 * IPSRCCLS - Indicates you have specified a source class.
52 * IPTRGCLS - Indicates you have specified a target class.
53 * IPFGPID  - Indicates you have specified a pathid.
54 * IPFGMID  - Indicates you have specified a message ID.
55 * IPNORPY  - Indicates a one-way message. No reply expected.
56 * IPALL    - Indicates that all paths are affected.
57 */
58#define IUCV_IPSRCCLS	0x01
59#define IUCV_IPTRGCLS	0x01
60#define IUCV_IPFGPID	0x02
61#define IUCV_IPFGMID	0x04
62#define IUCV_IPNORPY	0x10
63#define IUCV_IPALL	0x80
64
65static int iucv_bus_match(struct device *dev, struct device_driver *drv)
66{
67	return 0;
68}
69
70struct bus_type iucv_bus = {
71	.name = "iucv",
72	.match = iucv_bus_match,
73};
74EXPORT_SYMBOL(iucv_bus);
75
76struct device *iucv_root;
77EXPORT_SYMBOL(iucv_root);
78
79static int iucv_available;
80
81/* General IUCV interrupt structure */
82struct iucv_irq_data {
83	u16 ippathid;
84	u8  ipflags1;
85	u8  iptype;
86	u32 res2[9];
87};
88
89struct iucv_irq_list {
90	struct list_head list;
91	struct iucv_irq_data data;
92};
93
94static struct iucv_irq_data *iucv_irq_data[NR_CPUS];
95static cpumask_t iucv_buffer_cpumask = { CPU_BITS_NONE };
96static cpumask_t iucv_irq_cpumask = { CPU_BITS_NONE };
97
98/*
99 * Queue of interrupt buffers lock for delivery via the tasklet
100 * (fast but can't call smp_call_function).
101 */
102static LIST_HEAD(iucv_task_queue);
103
104/*
105 * The tasklet for fast delivery of iucv interrupts.
106 */
107static void iucv_tasklet_fn(unsigned long);
108static DECLARE_TASKLET_OLD(iucv_tasklet, iucv_tasklet_fn);
109
110/*
111 * Queue of interrupt buffers for delivery via a work queue
112 * (slower but can call smp_call_function).
113 */
114static LIST_HEAD(iucv_work_queue);
115
116/*
117 * The work element to deliver path pending interrupts.
118 */
119static void iucv_work_fn(struct work_struct *work);
120static DECLARE_WORK(iucv_work, iucv_work_fn);
121
122/*
123 * Spinlock protecting task and work queue.
124 */
125static DEFINE_SPINLOCK(iucv_queue_lock);
126
127enum iucv_command_codes {
128	IUCV_QUERY = 0,
129	IUCV_RETRIEVE_BUFFER = 2,
130	IUCV_SEND = 4,
131	IUCV_RECEIVE = 5,
132	IUCV_REPLY = 6,
133	IUCV_REJECT = 8,
134	IUCV_PURGE = 9,
135	IUCV_ACCEPT = 10,
136	IUCV_CONNECT = 11,
137	IUCV_DECLARE_BUFFER = 12,
138	IUCV_QUIESCE = 13,
139	IUCV_RESUME = 14,
140	IUCV_SEVER = 15,
141	IUCV_SETMASK = 16,
142	IUCV_SETCONTROLMASK = 17,
143};
144
145/*
146 * Error messages that are used with the iucv_sever function. They get
147 * converted to EBCDIC.
148 */
149static char iucv_error_no_listener[16] = "NO LISTENER";
150static char iucv_error_no_memory[16] = "NO MEMORY";
151static char iucv_error_pathid[16] = "INVALID PATHID";
152
153/*
154 * iucv_handler_list: List of registered handlers.
155 */
156static LIST_HEAD(iucv_handler_list);
157
158/*
159 * iucv_path_table: array of pointers to iucv_path structures.
160 */
161static struct iucv_path **iucv_path_table;
162static unsigned long iucv_max_pathid;
163
164/*
165 * iucv_lock: spinlock protecting iucv_handler_list and iucv_pathid_table
166 */
167static DEFINE_SPINLOCK(iucv_table_lock);
168
169/*
170 * iucv_active_cpu: contains the number of the cpu executing the tasklet
171 * or the work handler. Needed for iucv_path_sever called from tasklet.
172 */
173static int iucv_active_cpu = -1;
174
175/*
176 * Mutex and wait queue for iucv_register/iucv_unregister.
177 */
178static DEFINE_MUTEX(iucv_register_mutex);
179
180/*
181 * Counter for number of non-smp capable handlers.
182 */
183static int iucv_nonsmp_handler;
184
185/*
186 * IUCV control data structure. Used by iucv_path_accept, iucv_path_connect,
187 * iucv_path_quiesce and iucv_path_sever.
188 */
189struct iucv_cmd_control {
190	u16 ippathid;
191	u8  ipflags1;
192	u8  iprcode;
193	u16 ipmsglim;
194	u16 res1;
195	u8  ipvmid[8];
196	u8  ipuser[16];
197	u8  iptarget[8];
198} __attribute__ ((packed,aligned(8)));
199
200/*
201 * Data in parameter list iucv structure. Used by iucv_message_send,
202 * iucv_message_send2way and iucv_message_reply.
203 */
204struct iucv_cmd_dpl {
205	u16 ippathid;
206	u8  ipflags1;
207	u8  iprcode;
208	u32 ipmsgid;
209	u32 iptrgcls;
210	u8  iprmmsg[8];
211	u32 ipsrccls;
212	u32 ipmsgtag;
213	u32 ipbfadr2;
214	u32 ipbfln2f;
215	u32 res;
216} __attribute__ ((packed,aligned(8)));
217
218/*
219 * Data in buffer iucv structure. Used by iucv_message_receive,
220 * iucv_message_reject, iucv_message_send, iucv_message_send2way
221 * and iucv_declare_cpu.
222 */
223struct iucv_cmd_db {
224	u16 ippathid;
225	u8  ipflags1;
226	u8  iprcode;
227	u32 ipmsgid;
228	u32 iptrgcls;
229	u32 ipbfadr1;
230	u32 ipbfln1f;
231	u32 ipsrccls;
232	u32 ipmsgtag;
233	u32 ipbfadr2;
234	u32 ipbfln2f;
235	u32 res;
236} __attribute__ ((packed,aligned(8)));
237
238/*
239 * Purge message iucv structure. Used by iucv_message_purge.
240 */
241struct iucv_cmd_purge {
242	u16 ippathid;
243	u8  ipflags1;
244	u8  iprcode;
245	u32 ipmsgid;
246	u8  ipaudit[3];
247	u8  res1[5];
248	u32 res2;
249	u32 ipsrccls;
250	u32 ipmsgtag;
251	u32 res3[3];
252} __attribute__ ((packed,aligned(8)));
253
254/*
255 * Set mask iucv structure. Used by iucv_enable_cpu.
256 */
257struct iucv_cmd_set_mask {
258	u8  ipmask;
259	u8  res1[2];
260	u8  iprcode;
261	u32 res2[9];
262} __attribute__ ((packed,aligned(8)));
263
264union iucv_param {
265	struct iucv_cmd_control ctrl;
266	struct iucv_cmd_dpl dpl;
267	struct iucv_cmd_db db;
268	struct iucv_cmd_purge purge;
269	struct iucv_cmd_set_mask set_mask;
270};
271
272/*
273 * Anchor for per-cpu IUCV command parameter block.
274 */
275static union iucv_param *iucv_param[NR_CPUS];
276static union iucv_param *iucv_param_irq[NR_CPUS];
277
278/**
279 * __iucv_call_b2f0
280 * @command: identifier of IUCV call to CP.
281 * @parm: pointer to a struct iucv_parm block
282 *
283 * Calls CP to execute IUCV commands.
284 *
285 * Returns the result of the CP IUCV call.
286 */
287static inline int __iucv_call_b2f0(int command, union iucv_param *parm)
288{
289	int cc;
290
291	asm volatile(
292		"	lgr	0,%[reg0]\n"
293		"	lgr	1,%[reg1]\n"
294		"	.long	0xb2f01000\n"
295		"	ipm	%[cc]\n"
296		"	srl	%[cc],28\n"
297		: [cc] "=&d" (cc), "+m" (*parm)
298		: [reg0] "d" ((unsigned long)command),
299		  [reg1] "d" ((unsigned long)parm)
300		: "cc", "0", "1");
301	return cc;
302}
303
304static inline int iucv_call_b2f0(int command, union iucv_param *parm)
305{
306	int ccode;
307
308	ccode = __iucv_call_b2f0(command, parm);
309	return ccode == 1 ? parm->ctrl.iprcode : ccode;
310}
311
312/*
313 * iucv_query_maxconn
314 *
315 * Determines the maximum number of connections that may be established.
316 *
317 * Returns the maximum number of connections or -EPERM is IUCV is not
318 * available.
319 */
320static int __iucv_query_maxconn(void *param, unsigned long *max_pathid)
321{
322	unsigned long reg1 = virt_to_phys(param);
323	int cc;
324
325	asm volatile (
326		"	lghi	0,%[cmd]\n"
327		"	lgr	1,%[reg1]\n"
328		"	.long	0xb2f01000\n"
329		"	ipm	%[cc]\n"
330		"	srl	%[cc],28\n"
331		"	lgr	%[reg1],1\n"
332		: [cc] "=&d" (cc), [reg1] "+&d" (reg1)
333		: [cmd] "K" (IUCV_QUERY)
334		: "cc", "0", "1");
335	*max_pathid = reg1;
336	return cc;
337}
338
339static int iucv_query_maxconn(void)
340{
341	unsigned long max_pathid;
342	void *param;
343	int ccode;
344
345	param = kzalloc(sizeof(union iucv_param), GFP_KERNEL | GFP_DMA);
346	if (!param)
347		return -ENOMEM;
348	ccode = __iucv_query_maxconn(param, &max_pathid);
349	if (ccode == 0)
350		iucv_max_pathid = max_pathid;
351	kfree(param);
352	return ccode ? -EPERM : 0;
353}
354
355/**
356 * iucv_allow_cpu
357 * @data: unused
358 *
359 * Allow iucv interrupts on this cpu.
360 */
361static void iucv_allow_cpu(void *data)
362{
363	int cpu = smp_processor_id();
364	union iucv_param *parm;
365
366	/*
367	 * Enable all iucv interrupts.
368	 * ipmask contains bits for the different interrupts
369	 *	0x80 - Flag to allow nonpriority message pending interrupts
370	 *	0x40 - Flag to allow priority message pending interrupts
371	 *	0x20 - Flag to allow nonpriority message completion interrupts
372	 *	0x10 - Flag to allow priority message completion interrupts
373	 *	0x08 - Flag to allow IUCV control interrupts
374	 */
375	parm = iucv_param_irq[cpu];
376	memset(parm, 0, sizeof(union iucv_param));
377	parm->set_mask.ipmask = 0xf8;
378	iucv_call_b2f0(IUCV_SETMASK, parm);
379
380	/*
381	 * Enable all iucv control interrupts.
382	 * ipmask contains bits for the different interrupts
383	 *	0x80 - Flag to allow pending connections interrupts
384	 *	0x40 - Flag to allow connection complete interrupts
385	 *	0x20 - Flag to allow connection severed interrupts
386	 *	0x10 - Flag to allow connection quiesced interrupts
387	 *	0x08 - Flag to allow connection resumed interrupts
388	 */
389	memset(parm, 0, sizeof(union iucv_param));
390	parm->set_mask.ipmask = 0xf8;
391	iucv_call_b2f0(IUCV_SETCONTROLMASK, parm);
392	/* Set indication that iucv interrupts are allowed for this cpu. */
393	cpumask_set_cpu(cpu, &iucv_irq_cpumask);
394}
395
396/**
397 * iucv_block_cpu
398 * @data: unused
399 *
400 * Block iucv interrupts on this cpu.
401 */
402static void iucv_block_cpu(void *data)
403{
404	int cpu = smp_processor_id();
405	union iucv_param *parm;
406
407	/* Disable all iucv interrupts. */
408	parm = iucv_param_irq[cpu];
409	memset(parm, 0, sizeof(union iucv_param));
410	iucv_call_b2f0(IUCV_SETMASK, parm);
411
412	/* Clear indication that iucv interrupts are allowed for this cpu. */
413	cpumask_clear_cpu(cpu, &iucv_irq_cpumask);
414}
415
416/**
417 * iucv_declare_cpu
418 * @data: unused
419 *
420 * Declare a interrupt buffer on this cpu.
421 */
422static void iucv_declare_cpu(void *data)
423{
424	int cpu = smp_processor_id();
425	union iucv_param *parm;
426	int rc;
427
428	if (cpumask_test_cpu(cpu, &iucv_buffer_cpumask))
429		return;
430
431	/* Declare interrupt buffer. */
432	parm = iucv_param_irq[cpu];
433	memset(parm, 0, sizeof(union iucv_param));
434	parm->db.ipbfadr1 = virt_to_phys(iucv_irq_data[cpu]);
435	rc = iucv_call_b2f0(IUCV_DECLARE_BUFFER, parm);
436	if (rc) {
437		char *err = "Unknown";
438		switch (rc) {
439		case 0x03:
440			err = "Directory error";
441			break;
442		case 0x0a:
443			err = "Invalid length";
444			break;
445		case 0x13:
446			err = "Buffer already exists";
447			break;
448		case 0x3e:
449			err = "Buffer overlap";
450			break;
451		case 0x5c:
452			err = "Paging or storage error";
453			break;
454		}
455		pr_warn("Defining an interrupt buffer on CPU %i failed with 0x%02x (%s)\n",
456			cpu, rc, err);
457		return;
458	}
459
460	/* Set indication that an iucv buffer exists for this cpu. */
461	cpumask_set_cpu(cpu, &iucv_buffer_cpumask);
462
463	if (iucv_nonsmp_handler == 0 || cpumask_empty(&iucv_irq_cpumask))
464		/* Enable iucv interrupts on this cpu. */
465		iucv_allow_cpu(NULL);
466	else
467		/* Disable iucv interrupts on this cpu. */
468		iucv_block_cpu(NULL);
469}
470
471/**
472 * iucv_retrieve_cpu
473 * @data: unused
474 *
475 * Retrieve interrupt buffer on this cpu.
476 */
477static void iucv_retrieve_cpu(void *data)
478{
479	int cpu = smp_processor_id();
480	union iucv_param *parm;
481
482	if (!cpumask_test_cpu(cpu, &iucv_buffer_cpumask))
483		return;
484
485	/* Block iucv interrupts. */
486	iucv_block_cpu(NULL);
487
488	/* Retrieve interrupt buffer. */
489	parm = iucv_param_irq[cpu];
490	iucv_call_b2f0(IUCV_RETRIEVE_BUFFER, parm);
491
492	/* Clear indication that an iucv buffer exists for this cpu. */
493	cpumask_clear_cpu(cpu, &iucv_buffer_cpumask);
494}
495
496/*
497 * iucv_setmask_mp
498 *
499 * Allow iucv interrupts on all cpus.
500 */
501static void iucv_setmask_mp(void)
502{
503	int cpu;
504
505	cpus_read_lock();
506	for_each_online_cpu(cpu)
507		/* Enable all cpus with a declared buffer. */
508		if (cpumask_test_cpu(cpu, &iucv_buffer_cpumask) &&
509		    !cpumask_test_cpu(cpu, &iucv_irq_cpumask))
510			smp_call_function_single(cpu, iucv_allow_cpu,
511						 NULL, 1);
512	cpus_read_unlock();
513}
514
515/*
516 * iucv_setmask_up
517 *
518 * Allow iucv interrupts on a single cpu.
519 */
520static void iucv_setmask_up(void)
521{
522	cpumask_t cpumask;
523	int cpu;
524
525	/* Disable all cpu but the first in cpu_irq_cpumask. */
526	cpumask_copy(&cpumask, &iucv_irq_cpumask);
527	cpumask_clear_cpu(cpumask_first(&iucv_irq_cpumask), &cpumask);
528	for_each_cpu(cpu, &cpumask)
529		smp_call_function_single(cpu, iucv_block_cpu, NULL, 1);
530}
531
532/*
533 * iucv_enable
534 *
535 * This function makes iucv ready for use. It allocates the pathid
536 * table, declares an iucv interrupt buffer and enables the iucv
537 * interrupts. Called when the first user has registered an iucv
538 * handler.
539 */
540static int iucv_enable(void)
541{
542	size_t alloc_size;
543	int cpu, rc;
544
545	cpus_read_lock();
546	rc = -ENOMEM;
547	alloc_size = iucv_max_pathid * sizeof(*iucv_path_table);
548	iucv_path_table = kzalloc(alloc_size, GFP_KERNEL);
549	if (!iucv_path_table)
550		goto out;
551	/* Declare per cpu buffers. */
552	rc = -EIO;
553	for_each_online_cpu(cpu)
554		smp_call_function_single(cpu, iucv_declare_cpu, NULL, 1);
555	if (cpumask_empty(&iucv_buffer_cpumask))
556		/* No cpu could declare an iucv buffer. */
557		goto out;
558	cpus_read_unlock();
559	return 0;
560out:
561	kfree(iucv_path_table);
562	iucv_path_table = NULL;
563	cpus_read_unlock();
564	return rc;
565}
566
567/*
568 * iucv_disable
569 *
570 * This function shuts down iucv. It disables iucv interrupts, retrieves
571 * the iucv interrupt buffer and frees the pathid table. Called after the
572 * last user unregister its iucv handler.
573 */
574static void iucv_disable(void)
575{
576	cpus_read_lock();
577	on_each_cpu(iucv_retrieve_cpu, NULL, 1);
578	kfree(iucv_path_table);
579	iucv_path_table = NULL;
580	cpus_read_unlock();
581}
582
583static int iucv_cpu_dead(unsigned int cpu)
584{
585	kfree(iucv_param_irq[cpu]);
586	iucv_param_irq[cpu] = NULL;
587	kfree(iucv_param[cpu]);
588	iucv_param[cpu] = NULL;
589	kfree(iucv_irq_data[cpu]);
590	iucv_irq_data[cpu] = NULL;
591	return 0;
592}
593
594static int iucv_cpu_prepare(unsigned int cpu)
595{
596	/* Note: GFP_DMA used to get memory below 2G */
597	iucv_irq_data[cpu] = kmalloc_node(sizeof(struct iucv_irq_data),
598			     GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
599	if (!iucv_irq_data[cpu])
600		goto out_free;
601
602	/* Allocate parameter blocks. */
603	iucv_param[cpu] = kmalloc_node(sizeof(union iucv_param),
604			  GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
605	if (!iucv_param[cpu])
606		goto out_free;
607
608	iucv_param_irq[cpu] = kmalloc_node(sizeof(union iucv_param),
609			  GFP_KERNEL|GFP_DMA, cpu_to_node(cpu));
610	if (!iucv_param_irq[cpu])
611		goto out_free;
612
613	return 0;
614
615out_free:
616	iucv_cpu_dead(cpu);
617	return -ENOMEM;
618}
619
620static int iucv_cpu_online(unsigned int cpu)
621{
622	if (!iucv_path_table)
623		return 0;
624	iucv_declare_cpu(NULL);
625	return 0;
626}
627
628static int iucv_cpu_down_prep(unsigned int cpu)
629{
630	cpumask_t cpumask;
631
632	if (!iucv_path_table)
633		return 0;
634
635	cpumask_copy(&cpumask, &iucv_buffer_cpumask);
636	cpumask_clear_cpu(cpu, &cpumask);
637	if (cpumask_empty(&cpumask))
638		/* Can't offline last IUCV enabled cpu. */
639		return -EINVAL;
640
641	iucv_retrieve_cpu(NULL);
642	if (!cpumask_empty(&iucv_irq_cpumask))
643		return 0;
644	smp_call_function_single(cpumask_first(&iucv_buffer_cpumask),
645				 iucv_allow_cpu, NULL, 1);
646	return 0;
647}
648
649/**
650 * iucv_sever_pathid
651 * @pathid: path identification number.
652 * @userdata: 16-bytes of user data.
653 *
654 * Sever an iucv path to free up the pathid. Used internally.
655 */
656static int iucv_sever_pathid(u16 pathid, u8 *userdata)
657{
658	union iucv_param *parm;
659
660	parm = iucv_param_irq[smp_processor_id()];
661	memset(parm, 0, sizeof(union iucv_param));
662	if (userdata)
663		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
664	parm->ctrl.ippathid = pathid;
665	return iucv_call_b2f0(IUCV_SEVER, parm);
666}
667
668/**
669 * __iucv_cleanup_queue
670 * @dummy: unused dummy argument
671 *
672 * Nop function called via smp_call_function to force work items from
673 * pending external iucv interrupts to the work queue.
674 */
675static void __iucv_cleanup_queue(void *dummy)
676{
677}
678
679/**
680 * iucv_cleanup_queue
681 *
682 * Function called after a path has been severed to find all remaining
683 * work items for the now stale pathid. The caller needs to hold the
684 * iucv_table_lock.
685 */
686static void iucv_cleanup_queue(void)
687{
688	struct iucv_irq_list *p, *n;
689
690	/*
691	 * When a path is severed, the pathid can be reused immediately
692	 * on a iucv connect or a connection pending interrupt. Remove
693	 * all entries from the task queue that refer to a stale pathid
694	 * (iucv_path_table[ix] == NULL). Only then do the iucv connect
695	 * or deliver the connection pending interrupt. To get all the
696	 * pending interrupts force them to the work queue by calling
697	 * an empty function on all cpus.
698	 */
699	smp_call_function(__iucv_cleanup_queue, NULL, 1);
700	spin_lock_irq(&iucv_queue_lock);
701	list_for_each_entry_safe(p, n, &iucv_task_queue, list) {
702		/* Remove stale work items from the task queue. */
703		if (iucv_path_table[p->data.ippathid] == NULL) {
704			list_del(&p->list);
705			kfree(p);
706		}
707	}
708	spin_unlock_irq(&iucv_queue_lock);
709}
710
711/**
712 * iucv_register:
713 * @handler: address of iucv handler structure
714 * @smp: != 0 indicates that the handler can deal with out of order messages
715 *
716 * Registers a driver with IUCV.
717 *
718 * Returns 0 on success, -ENOMEM if the memory allocation for the pathid
719 * table failed, or -EIO if IUCV_DECLARE_BUFFER failed on all cpus.
720 */
721int iucv_register(struct iucv_handler *handler, int smp)
722{
723	int rc;
724
725	if (!iucv_available)
726		return -ENOSYS;
727	mutex_lock(&iucv_register_mutex);
728	if (!smp)
729		iucv_nonsmp_handler++;
730	if (list_empty(&iucv_handler_list)) {
731		rc = iucv_enable();
732		if (rc)
733			goto out_mutex;
734	} else if (!smp && iucv_nonsmp_handler == 1)
735		iucv_setmask_up();
736	INIT_LIST_HEAD(&handler->paths);
737
738	spin_lock_bh(&iucv_table_lock);
739	list_add_tail(&handler->list, &iucv_handler_list);
740	spin_unlock_bh(&iucv_table_lock);
741	rc = 0;
742out_mutex:
743	mutex_unlock(&iucv_register_mutex);
744	return rc;
745}
746EXPORT_SYMBOL(iucv_register);
747
748/**
749 * iucv_unregister
750 * @handler:  address of iucv handler structure
751 * @smp: != 0 indicates that the handler can deal with out of order messages
752 *
753 * Unregister driver from IUCV.
754 */
755void iucv_unregister(struct iucv_handler *handler, int smp)
756{
757	struct iucv_path *p, *n;
758
759	mutex_lock(&iucv_register_mutex);
760	spin_lock_bh(&iucv_table_lock);
761	/* Remove handler from the iucv_handler_list. */
762	list_del_init(&handler->list);
763	/* Sever all pathids still referring to the handler. */
764	list_for_each_entry_safe(p, n, &handler->paths, list) {
765		iucv_sever_pathid(p->pathid, NULL);
766		iucv_path_table[p->pathid] = NULL;
767		list_del(&p->list);
768		iucv_path_free(p);
769	}
770	spin_unlock_bh(&iucv_table_lock);
771	if (!smp)
772		iucv_nonsmp_handler--;
773	if (list_empty(&iucv_handler_list))
774		iucv_disable();
775	else if (!smp && iucv_nonsmp_handler == 0)
776		iucv_setmask_mp();
777	mutex_unlock(&iucv_register_mutex);
778}
779EXPORT_SYMBOL(iucv_unregister);
780
781static int iucv_reboot_event(struct notifier_block *this,
782			     unsigned long event, void *ptr)
783{
784	int i;
785
786	if (cpumask_empty(&iucv_irq_cpumask))
787		return NOTIFY_DONE;
788
789	cpus_read_lock();
790	on_each_cpu_mask(&iucv_irq_cpumask, iucv_block_cpu, NULL, 1);
791	preempt_disable();
792	for (i = 0; i < iucv_max_pathid; i++) {
793		if (iucv_path_table[i])
794			iucv_sever_pathid(i, NULL);
795	}
796	preempt_enable();
797	cpus_read_unlock();
798	iucv_disable();
799	return NOTIFY_DONE;
800}
801
802static struct notifier_block iucv_reboot_notifier = {
803	.notifier_call = iucv_reboot_event,
804};
805
806/**
807 * iucv_path_accept
808 * @path: address of iucv path structure
809 * @handler: address of iucv handler structure
810 * @userdata: 16 bytes of data reflected to the communication partner
811 * @private: private data passed to interrupt handlers for this path
812 *
813 * This function is issued after the user received a connection pending
814 * external interrupt and now wishes to complete the IUCV communication path.
815 *
816 * Returns the result of the CP IUCV call.
817 */
818int iucv_path_accept(struct iucv_path *path, struct iucv_handler *handler,
819		     u8 *userdata, void *private)
820{
821	union iucv_param *parm;
822	int rc;
823
824	local_bh_disable();
825	if (cpumask_empty(&iucv_buffer_cpumask)) {
826		rc = -EIO;
827		goto out;
828	}
829	/* Prepare parameter block. */
830	parm = iucv_param[smp_processor_id()];
831	memset(parm, 0, sizeof(union iucv_param));
832	parm->ctrl.ippathid = path->pathid;
833	parm->ctrl.ipmsglim = path->msglim;
834	if (userdata)
835		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
836	parm->ctrl.ipflags1 = path->flags;
837
838	rc = iucv_call_b2f0(IUCV_ACCEPT, parm);
839	if (!rc) {
840		path->private = private;
841		path->msglim = parm->ctrl.ipmsglim;
842		path->flags = parm->ctrl.ipflags1;
843	}
844out:
845	local_bh_enable();
846	return rc;
847}
848EXPORT_SYMBOL(iucv_path_accept);
849
850/**
851 * iucv_path_connect
852 * @path: address of iucv path structure
853 * @handler: address of iucv handler structure
854 * @userid: 8-byte user identification
855 * @system: 8-byte target system identification
856 * @userdata: 16 bytes of data reflected to the communication partner
857 * @private: private data passed to interrupt handlers for this path
858 *
859 * This function establishes an IUCV path. Although the connect may complete
860 * successfully, you are not able to use the path until you receive an IUCV
861 * Connection Complete external interrupt.
862 *
863 * Returns the result of the CP IUCV call.
864 */
865int iucv_path_connect(struct iucv_path *path, struct iucv_handler *handler,
866		      u8 *userid, u8 *system, u8 *userdata,
867		      void *private)
868{
869	union iucv_param *parm;
870	int rc;
871
872	spin_lock_bh(&iucv_table_lock);
873	iucv_cleanup_queue();
874	if (cpumask_empty(&iucv_buffer_cpumask)) {
875		rc = -EIO;
876		goto out;
877	}
878	parm = iucv_param[smp_processor_id()];
879	memset(parm, 0, sizeof(union iucv_param));
880	parm->ctrl.ipmsglim = path->msglim;
881	parm->ctrl.ipflags1 = path->flags;
882	if (userid) {
883		memcpy(parm->ctrl.ipvmid, userid, sizeof(parm->ctrl.ipvmid));
884		ASCEBC(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
885		EBC_TOUPPER(parm->ctrl.ipvmid, sizeof(parm->ctrl.ipvmid));
886	}
887	if (system) {
888		memcpy(parm->ctrl.iptarget, system,
889		       sizeof(parm->ctrl.iptarget));
890		ASCEBC(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
891		EBC_TOUPPER(parm->ctrl.iptarget, sizeof(parm->ctrl.iptarget));
892	}
893	if (userdata)
894		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
895
896	rc = iucv_call_b2f0(IUCV_CONNECT, parm);
897	if (!rc) {
898		if (parm->ctrl.ippathid < iucv_max_pathid) {
899			path->pathid = parm->ctrl.ippathid;
900			path->msglim = parm->ctrl.ipmsglim;
901			path->flags = parm->ctrl.ipflags1;
902			path->handler = handler;
903			path->private = private;
904			list_add_tail(&path->list, &handler->paths);
905			iucv_path_table[path->pathid] = path;
906		} else {
907			iucv_sever_pathid(parm->ctrl.ippathid,
908					  iucv_error_pathid);
909			rc = -EIO;
910		}
911	}
912out:
913	spin_unlock_bh(&iucv_table_lock);
914	return rc;
915}
916EXPORT_SYMBOL(iucv_path_connect);
917
918/**
919 * iucv_path_quiesce:
920 * @path: address of iucv path structure
921 * @userdata: 16 bytes of data reflected to the communication partner
922 *
923 * This function temporarily suspends incoming messages on an IUCV path.
924 * You can later reactivate the path by invoking the iucv_resume function.
925 *
926 * Returns the result from the CP IUCV call.
927 */
928int iucv_path_quiesce(struct iucv_path *path, u8 *userdata)
929{
930	union iucv_param *parm;
931	int rc;
932
933	local_bh_disable();
934	if (cpumask_empty(&iucv_buffer_cpumask)) {
935		rc = -EIO;
936		goto out;
937	}
938	parm = iucv_param[smp_processor_id()];
939	memset(parm, 0, sizeof(union iucv_param));
940	if (userdata)
941		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
942	parm->ctrl.ippathid = path->pathid;
943	rc = iucv_call_b2f0(IUCV_QUIESCE, parm);
944out:
945	local_bh_enable();
946	return rc;
947}
948EXPORT_SYMBOL(iucv_path_quiesce);
949
950/**
951 * iucv_path_resume:
952 * @path: address of iucv path structure
953 * @userdata: 16 bytes of data reflected to the communication partner
954 *
955 * This function resumes incoming messages on an IUCV path that has
956 * been stopped with iucv_path_quiesce.
957 *
958 * Returns the result from the CP IUCV call.
959 */
960int iucv_path_resume(struct iucv_path *path, u8 *userdata)
961{
962	union iucv_param *parm;
963	int rc;
964
965	local_bh_disable();
966	if (cpumask_empty(&iucv_buffer_cpumask)) {
967		rc = -EIO;
968		goto out;
969	}
970	parm = iucv_param[smp_processor_id()];
971	memset(parm, 0, sizeof(union iucv_param));
972	if (userdata)
973		memcpy(parm->ctrl.ipuser, userdata, sizeof(parm->ctrl.ipuser));
974	parm->ctrl.ippathid = path->pathid;
975	rc = iucv_call_b2f0(IUCV_RESUME, parm);
976out:
977	local_bh_enable();
978	return rc;
979}
980
981/**
982 * iucv_path_sever
983 * @path: address of iucv path structure
984 * @userdata: 16 bytes of data reflected to the communication partner
985 *
986 * This function terminates an IUCV path.
987 *
988 * Returns the result from the CP IUCV call.
989 */
990int iucv_path_sever(struct iucv_path *path, u8 *userdata)
991{
992	int rc;
993
994	preempt_disable();
995	if (cpumask_empty(&iucv_buffer_cpumask)) {
996		rc = -EIO;
997		goto out;
998	}
999	if (iucv_active_cpu != smp_processor_id())
1000		spin_lock_bh(&iucv_table_lock);
1001	rc = iucv_sever_pathid(path->pathid, userdata);
1002	iucv_path_table[path->pathid] = NULL;
1003	list_del_init(&path->list);
1004	if (iucv_active_cpu != smp_processor_id())
1005		spin_unlock_bh(&iucv_table_lock);
1006out:
1007	preempt_enable();
1008	return rc;
1009}
1010EXPORT_SYMBOL(iucv_path_sever);
1011
1012/**
1013 * iucv_message_purge
1014 * @path: address of iucv path structure
1015 * @msg: address of iucv msg structure
1016 * @srccls: source class of message
1017 *
1018 * Cancels a message you have sent.
1019 *
1020 * Returns the result from the CP IUCV call.
1021 */
1022int iucv_message_purge(struct iucv_path *path, struct iucv_message *msg,
1023		       u32 srccls)
1024{
1025	union iucv_param *parm;
1026	int rc;
1027
1028	local_bh_disable();
1029	if (cpumask_empty(&iucv_buffer_cpumask)) {
1030		rc = -EIO;
1031		goto out;
1032	}
1033	parm = iucv_param[smp_processor_id()];
1034	memset(parm, 0, sizeof(union iucv_param));
1035	parm->purge.ippathid = path->pathid;
1036	parm->purge.ipmsgid = msg->id;
1037	parm->purge.ipsrccls = srccls;
1038	parm->purge.ipflags1 = IUCV_IPSRCCLS | IUCV_IPFGMID | IUCV_IPFGPID;
1039	rc = iucv_call_b2f0(IUCV_PURGE, parm);
1040	if (!rc) {
1041		msg->audit = (*(u32 *) &parm->purge.ipaudit) >> 8;
1042		msg->tag = parm->purge.ipmsgtag;
1043	}
1044out:
1045	local_bh_enable();
1046	return rc;
1047}
1048EXPORT_SYMBOL(iucv_message_purge);
1049
1050/**
1051 * iucv_message_receive_iprmdata
1052 * @path: address of iucv path structure
1053 * @msg: address of iucv msg structure
1054 * @flags: how the message is received (IUCV_IPBUFLST)
1055 * @buffer: address of data buffer or address of struct iucv_array
1056 * @size: length of data buffer
1057 * @residual:
1058 *
1059 * Internal function used by iucv_message_receive and __iucv_message_receive
1060 * to receive RMDATA data stored in struct iucv_message.
1061 */
1062static int iucv_message_receive_iprmdata(struct iucv_path *path,
1063					 struct iucv_message *msg,
1064					 u8 flags, void *buffer,
1065					 size_t size, size_t *residual)
1066{
1067	struct iucv_array *array;
1068	u8 *rmmsg;
1069	size_t copy;
1070
1071	/*
1072	 * Message is 8 bytes long and has been stored to the
1073	 * message descriptor itself.
1074	 */
1075	if (residual)
1076		*residual = abs(size - 8);
1077	rmmsg = msg->rmmsg;
1078	if (flags & IUCV_IPBUFLST) {
1079		/* Copy to struct iucv_array. */
1080		size = (size < 8) ? size : 8;
1081		for (array = buffer; size > 0; array++) {
1082			copy = min_t(size_t, size, array->length);
1083			memcpy((u8 *)(addr_t) array->address,
1084				rmmsg, copy);
1085			rmmsg += copy;
1086			size -= copy;
1087		}
1088	} else {
1089		/* Copy to direct buffer. */
1090		memcpy(buffer, rmmsg, min_t(size_t, size, 8));
1091	}
1092	return 0;
1093}
1094
1095/**
1096 * __iucv_message_receive
1097 * @path: address of iucv path structure
1098 * @msg: address of iucv msg structure
1099 * @flags: how the message is received (IUCV_IPBUFLST)
1100 * @buffer: address of data buffer or address of struct iucv_array
1101 * @size: length of data buffer
1102 * @residual:
1103 *
1104 * This function receives messages that are being sent to you over
1105 * established paths. This function will deal with RMDATA messages
1106 * embedded in struct iucv_message as well.
1107 *
1108 * Locking:	no locking
1109 *
1110 * Returns the result from the CP IUCV call.
1111 */
1112int __iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
1113			   u8 flags, void *buffer, size_t size, size_t *residual)
1114{
1115	union iucv_param *parm;
1116	int rc;
1117
1118	if (msg->flags & IUCV_IPRMDATA)
1119		return iucv_message_receive_iprmdata(path, msg, flags,
1120						     buffer, size, residual);
1121	if (cpumask_empty(&iucv_buffer_cpumask))
1122		return -EIO;
1123
1124	parm = iucv_param[smp_processor_id()];
1125	memset(parm, 0, sizeof(union iucv_param));
1126	parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1127	parm->db.ipbfln1f = (u32) size;
1128	parm->db.ipmsgid = msg->id;
1129	parm->db.ippathid = path->pathid;
1130	parm->db.iptrgcls = msg->class;
1131	parm->db.ipflags1 = (flags | IUCV_IPFGPID |
1132			     IUCV_IPFGMID | IUCV_IPTRGCLS);
1133	rc = iucv_call_b2f0(IUCV_RECEIVE, parm);
1134	if (!rc || rc == 5) {
1135		msg->flags = parm->db.ipflags1;
1136		if (residual)
1137			*residual = parm->db.ipbfln1f;
1138	}
1139	return rc;
1140}
1141EXPORT_SYMBOL(__iucv_message_receive);
1142
1143/**
1144 * iucv_message_receive
1145 * @path: address of iucv path structure
1146 * @msg: address of iucv msg structure
1147 * @flags: how the message is received (IUCV_IPBUFLST)
1148 * @buffer: address of data buffer or address of struct iucv_array
1149 * @size: length of data buffer
1150 * @residual:
1151 *
1152 * This function receives messages that are being sent to you over
1153 * established paths. This function will deal with RMDATA messages
1154 * embedded in struct iucv_message as well.
1155 *
1156 * Locking:	local_bh_enable/local_bh_disable
1157 *
1158 * Returns the result from the CP IUCV call.
1159 */
1160int iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
1161			 u8 flags, void *buffer, size_t size, size_t *residual)
1162{
1163	int rc;
1164
1165	if (msg->flags & IUCV_IPRMDATA)
1166		return iucv_message_receive_iprmdata(path, msg, flags,
1167						     buffer, size, residual);
1168	local_bh_disable();
1169	rc = __iucv_message_receive(path, msg, flags, buffer, size, residual);
1170	local_bh_enable();
1171	return rc;
1172}
1173EXPORT_SYMBOL(iucv_message_receive);
1174
1175/**
1176 * iucv_message_reject
1177 * @path: address of iucv path structure
1178 * @msg: address of iucv msg structure
1179 *
1180 * The reject function refuses a specified message. Between the time you
1181 * are notified of a message and the time that you complete the message,
1182 * the message may be rejected.
1183 *
1184 * Returns the result from the CP IUCV call.
1185 */
1186int iucv_message_reject(struct iucv_path *path, struct iucv_message *msg)
1187{
1188	union iucv_param *parm;
1189	int rc;
1190
1191	local_bh_disable();
1192	if (cpumask_empty(&iucv_buffer_cpumask)) {
1193		rc = -EIO;
1194		goto out;
1195	}
1196	parm = iucv_param[smp_processor_id()];
1197	memset(parm, 0, sizeof(union iucv_param));
1198	parm->db.ippathid = path->pathid;
1199	parm->db.ipmsgid = msg->id;
1200	parm->db.iptrgcls = msg->class;
1201	parm->db.ipflags1 = (IUCV_IPTRGCLS | IUCV_IPFGMID | IUCV_IPFGPID);
1202	rc = iucv_call_b2f0(IUCV_REJECT, parm);
1203out:
1204	local_bh_enable();
1205	return rc;
1206}
1207EXPORT_SYMBOL(iucv_message_reject);
1208
1209/**
1210 * iucv_message_reply
1211 * @path: address of iucv path structure
1212 * @msg: address of iucv msg structure
1213 * @flags: how the reply is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1214 * @reply: address of reply data buffer or address of struct iucv_array
1215 * @size: length of reply data buffer
1216 *
1217 * This function responds to the two-way messages that you receive. You
1218 * must identify completely the message to which you wish to reply. ie,
1219 * pathid, msgid, and trgcls. Prmmsg signifies the data is moved into
1220 * the parameter list.
1221 *
1222 * Returns the result from the CP IUCV call.
1223 */
1224int iucv_message_reply(struct iucv_path *path, struct iucv_message *msg,
1225		       u8 flags, void *reply, size_t size)
1226{
1227	union iucv_param *parm;
1228	int rc;
1229
1230	local_bh_disable();
1231	if (cpumask_empty(&iucv_buffer_cpumask)) {
1232		rc = -EIO;
1233		goto out;
1234	}
1235	parm = iucv_param[smp_processor_id()];
1236	memset(parm, 0, sizeof(union iucv_param));
1237	if (flags & IUCV_IPRMDATA) {
1238		parm->dpl.ippathid = path->pathid;
1239		parm->dpl.ipflags1 = flags;
1240		parm->dpl.ipmsgid = msg->id;
1241		parm->dpl.iptrgcls = msg->class;
1242		memcpy(parm->dpl.iprmmsg, reply, min_t(size_t, size, 8));
1243	} else {
1244		parm->db.ipbfadr1 = (u32)(addr_t) reply;
1245		parm->db.ipbfln1f = (u32) size;
1246		parm->db.ippathid = path->pathid;
1247		parm->db.ipflags1 = flags;
1248		parm->db.ipmsgid = msg->id;
1249		parm->db.iptrgcls = msg->class;
1250	}
1251	rc = iucv_call_b2f0(IUCV_REPLY, parm);
1252out:
1253	local_bh_enable();
1254	return rc;
1255}
1256EXPORT_SYMBOL(iucv_message_reply);
1257
1258/**
1259 * __iucv_message_send
1260 * @path: address of iucv path structure
1261 * @msg: address of iucv msg structure
1262 * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1263 * @srccls: source class of message
1264 * @buffer: address of send buffer or address of struct iucv_array
1265 * @size: length of send buffer
1266 *
1267 * This function transmits data to another application. Data to be
1268 * transmitted is in a buffer and this is a one-way message and the
1269 * receiver will not reply to the message.
1270 *
1271 * Locking:	no locking
1272 *
1273 * Returns the result from the CP IUCV call.
1274 */
1275int __iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
1276		      u8 flags, u32 srccls, void *buffer, size_t size)
1277{
1278	union iucv_param *parm;
1279	int rc;
1280
1281	if (cpumask_empty(&iucv_buffer_cpumask)) {
1282		rc = -EIO;
1283		goto out;
1284	}
1285	parm = iucv_param[smp_processor_id()];
1286	memset(parm, 0, sizeof(union iucv_param));
1287	if (flags & IUCV_IPRMDATA) {
1288		/* Message of 8 bytes can be placed into the parameter list. */
1289		parm->dpl.ippathid = path->pathid;
1290		parm->dpl.ipflags1 = flags | IUCV_IPNORPY;
1291		parm->dpl.iptrgcls = msg->class;
1292		parm->dpl.ipsrccls = srccls;
1293		parm->dpl.ipmsgtag = msg->tag;
1294		memcpy(parm->dpl.iprmmsg, buffer, 8);
1295	} else {
1296		parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1297		parm->db.ipbfln1f = (u32) size;
1298		parm->db.ippathid = path->pathid;
1299		parm->db.ipflags1 = flags | IUCV_IPNORPY;
1300		parm->db.iptrgcls = msg->class;
1301		parm->db.ipsrccls = srccls;
1302		parm->db.ipmsgtag = msg->tag;
1303	}
1304	rc = iucv_call_b2f0(IUCV_SEND, parm);
1305	if (!rc)
1306		msg->id = parm->db.ipmsgid;
1307out:
1308	return rc;
1309}
1310EXPORT_SYMBOL(__iucv_message_send);
1311
1312/**
1313 * iucv_message_send
1314 * @path: address of iucv path structure
1315 * @msg: address of iucv msg structure
1316 * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
1317 * @srccls: source class of message
1318 * @buffer: address of send buffer or address of struct iucv_array
1319 * @size: length of send buffer
1320 *
1321 * This function transmits data to another application. Data to be
1322 * transmitted is in a buffer and this is a one-way message and the
1323 * receiver will not reply to the message.
1324 *
1325 * Locking:	local_bh_enable/local_bh_disable
1326 *
1327 * Returns the result from the CP IUCV call.
1328 */
1329int iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
1330		      u8 flags, u32 srccls, void *buffer, size_t size)
1331{
1332	int rc;
1333
1334	local_bh_disable();
1335	rc = __iucv_message_send(path, msg, flags, srccls, buffer, size);
1336	local_bh_enable();
1337	return rc;
1338}
1339EXPORT_SYMBOL(iucv_message_send);
1340
1341/**
1342 * iucv_message_send2way
1343 * @path: address of iucv path structure
1344 * @msg: address of iucv msg structure
1345 * @flags: how the message is sent and the reply is received
1346 *	   (IUCV_IPRMDATA, IUCV_IPBUFLST, IUCV_IPPRTY, IUCV_ANSLST)
1347 * @srccls: source class of message
1348 * @buffer: address of send buffer or address of struct iucv_array
1349 * @size: length of send buffer
1350 * @answer: address of answer buffer or address of struct iucv_array
1351 * @asize: size of reply buffer
1352 * @residual: ignored
1353 *
1354 * This function transmits data to another application. Data to be
1355 * transmitted is in a buffer. The receiver of the send is expected to
1356 * reply to the message and a buffer is provided into which IUCV moves
1357 * the reply to this message.
1358 *
1359 * Returns the result from the CP IUCV call.
1360 */
1361int iucv_message_send2way(struct iucv_path *path, struct iucv_message *msg,
1362			  u8 flags, u32 srccls, void *buffer, size_t size,
1363			  void *answer, size_t asize, size_t *residual)
1364{
1365	union iucv_param *parm;
1366	int rc;
1367
1368	local_bh_disable();
1369	if (cpumask_empty(&iucv_buffer_cpumask)) {
1370		rc = -EIO;
1371		goto out;
1372	}
1373	parm = iucv_param[smp_processor_id()];
1374	memset(parm, 0, sizeof(union iucv_param));
1375	if (flags & IUCV_IPRMDATA) {
1376		parm->dpl.ippathid = path->pathid;
1377		parm->dpl.ipflags1 = path->flags;	/* priority message */
1378		parm->dpl.iptrgcls = msg->class;
1379		parm->dpl.ipsrccls = srccls;
1380		parm->dpl.ipmsgtag = msg->tag;
1381		parm->dpl.ipbfadr2 = (u32)(addr_t) answer;
1382		parm->dpl.ipbfln2f = (u32) asize;
1383		memcpy(parm->dpl.iprmmsg, buffer, 8);
1384	} else {
1385		parm->db.ippathid = path->pathid;
1386		parm->db.ipflags1 = path->flags;	/* priority message */
1387		parm->db.iptrgcls = msg->class;
1388		parm->db.ipsrccls = srccls;
1389		parm->db.ipmsgtag = msg->tag;
1390		parm->db.ipbfadr1 = (u32)(addr_t) buffer;
1391		parm->db.ipbfln1f = (u32) size;
1392		parm->db.ipbfadr2 = (u32)(addr_t) answer;
1393		parm->db.ipbfln2f = (u32) asize;
1394	}
1395	rc = iucv_call_b2f0(IUCV_SEND, parm);
1396	if (!rc)
1397		msg->id = parm->db.ipmsgid;
1398out:
1399	local_bh_enable();
1400	return rc;
1401}
1402EXPORT_SYMBOL(iucv_message_send2way);
1403
1404struct iucv_path_pending {
1405	u16 ippathid;
1406	u8  ipflags1;
1407	u8  iptype;
1408	u16 ipmsglim;
1409	u16 res1;
1410	u8  ipvmid[8];
1411	u8  ipuser[16];
1412	u32 res3;
1413	u8  ippollfg;
1414	u8  res4[3];
1415} __packed;
1416
1417/**
1418 * iucv_path_pending
1419 * @data: Pointer to external interrupt buffer
1420 *
1421 * Process connection pending work item. Called from tasklet while holding
1422 * iucv_table_lock.
1423 */
1424static void iucv_path_pending(struct iucv_irq_data *data)
1425{
1426	struct iucv_path_pending *ipp = (void *) data;
1427	struct iucv_handler *handler;
1428	struct iucv_path *path;
1429	char *error;
1430
1431	BUG_ON(iucv_path_table[ipp->ippathid]);
1432	/* New pathid, handler found. Create a new path struct. */
1433	error = iucv_error_no_memory;
1434	path = iucv_path_alloc(ipp->ipmsglim, ipp->ipflags1, GFP_ATOMIC);
1435	if (!path)
1436		goto out_sever;
1437	path->pathid = ipp->ippathid;
1438	iucv_path_table[path->pathid] = path;
1439	EBCASC(ipp->ipvmid, 8);
1440
1441	/* Call registered handler until one is found that wants the path. */
1442	list_for_each_entry(handler, &iucv_handler_list, list) {
1443		if (!handler->path_pending)
1444			continue;
1445		/*
1446		 * Add path to handler to allow a call to iucv_path_sever
1447		 * inside the path_pending function. If the handler returns
1448		 * an error remove the path from the handler again.
1449		 */
1450		list_add(&path->list, &handler->paths);
1451		path->handler = handler;
1452		if (!handler->path_pending(path, ipp->ipvmid, ipp->ipuser))
1453			return;
1454		list_del(&path->list);
1455		path->handler = NULL;
1456	}
1457	/* No handler wanted the path. */
1458	iucv_path_table[path->pathid] = NULL;
1459	iucv_path_free(path);
1460	error = iucv_error_no_listener;
1461out_sever:
1462	iucv_sever_pathid(ipp->ippathid, error);
1463}
1464
1465struct iucv_path_complete {
1466	u16 ippathid;
1467	u8  ipflags1;
1468	u8  iptype;
1469	u16 ipmsglim;
1470	u16 res1;
1471	u8  res2[8];
1472	u8  ipuser[16];
1473	u32 res3;
1474	u8  ippollfg;
1475	u8  res4[3];
1476} __packed;
1477
1478/**
1479 * iucv_path_complete
1480 * @data: Pointer to external interrupt buffer
1481 *
1482 * Process connection complete work item. Called from tasklet while holding
1483 * iucv_table_lock.
1484 */
1485static void iucv_path_complete(struct iucv_irq_data *data)
1486{
1487	struct iucv_path_complete *ipc = (void *) data;
1488	struct iucv_path *path = iucv_path_table[ipc->ippathid];
1489
1490	if (path)
1491		path->flags = ipc->ipflags1;
1492	if (path && path->handler && path->handler->path_complete)
1493		path->handler->path_complete(path, ipc->ipuser);
1494}
1495
1496struct iucv_path_severed {
1497	u16 ippathid;
1498	u8  res1;
1499	u8  iptype;
1500	u32 res2;
1501	u8  res3[8];
1502	u8  ipuser[16];
1503	u32 res4;
1504	u8  ippollfg;
1505	u8  res5[3];
1506} __packed;
1507
1508/**
1509 * iucv_path_severed
1510 * @data: Pointer to external interrupt buffer
1511 *
1512 * Process connection severed work item. Called from tasklet while holding
1513 * iucv_table_lock.
1514 */
1515static void iucv_path_severed(struct iucv_irq_data *data)
1516{
1517	struct iucv_path_severed *ips = (void *) data;
1518	struct iucv_path *path = iucv_path_table[ips->ippathid];
1519
1520	if (!path || !path->handler)	/* Already severed */
1521		return;
1522	if (path->handler->path_severed)
1523		path->handler->path_severed(path, ips->ipuser);
1524	else {
1525		iucv_sever_pathid(path->pathid, NULL);
1526		iucv_path_table[path->pathid] = NULL;
1527		list_del(&path->list);
1528		iucv_path_free(path);
1529	}
1530}
1531
1532struct iucv_path_quiesced {
1533	u16 ippathid;
1534	u8  res1;
1535	u8  iptype;
1536	u32 res2;
1537	u8  res3[8];
1538	u8  ipuser[16];
1539	u32 res4;
1540	u8  ippollfg;
1541	u8  res5[3];
1542} __packed;
1543
1544/**
1545 * iucv_path_quiesced
1546 * @data: Pointer to external interrupt buffer
1547 *
1548 * Process connection quiesced work item. Called from tasklet while holding
1549 * iucv_table_lock.
1550 */
1551static void iucv_path_quiesced(struct iucv_irq_data *data)
1552{
1553	struct iucv_path_quiesced *ipq = (void *) data;
1554	struct iucv_path *path = iucv_path_table[ipq->ippathid];
1555
1556	if (path && path->handler && path->handler->path_quiesced)
1557		path->handler->path_quiesced(path, ipq->ipuser);
1558}
1559
1560struct iucv_path_resumed {
1561	u16 ippathid;
1562	u8  res1;
1563	u8  iptype;
1564	u32 res2;
1565	u8  res3[8];
1566	u8  ipuser[16];
1567	u32 res4;
1568	u8  ippollfg;
1569	u8  res5[3];
1570} __packed;
1571
1572/**
1573 * iucv_path_resumed
1574 * @data: Pointer to external interrupt buffer
1575 *
1576 * Process connection resumed work item. Called from tasklet while holding
1577 * iucv_table_lock.
1578 */
1579static void iucv_path_resumed(struct iucv_irq_data *data)
1580{
1581	struct iucv_path_resumed *ipr = (void *) data;
1582	struct iucv_path *path = iucv_path_table[ipr->ippathid];
1583
1584	if (path && path->handler && path->handler->path_resumed)
1585		path->handler->path_resumed(path, ipr->ipuser);
1586}
1587
1588struct iucv_message_complete {
1589	u16 ippathid;
1590	u8  ipflags1;
1591	u8  iptype;
1592	u32 ipmsgid;
1593	u32 ipaudit;
1594	u8  iprmmsg[8];
1595	u32 ipsrccls;
1596	u32 ipmsgtag;
1597	u32 res;
1598	u32 ipbfln2f;
1599	u8  ippollfg;
1600	u8  res2[3];
1601} __packed;
1602
1603/**
1604 * iucv_message_complete
1605 * @data: Pointer to external interrupt buffer
1606 *
1607 * Process message complete work item. Called from tasklet while holding
1608 * iucv_table_lock.
1609 */
1610static void iucv_message_complete(struct iucv_irq_data *data)
1611{
1612	struct iucv_message_complete *imc = (void *) data;
1613	struct iucv_path *path = iucv_path_table[imc->ippathid];
1614	struct iucv_message msg;
1615
1616	if (path && path->handler && path->handler->message_complete) {
1617		msg.flags = imc->ipflags1;
1618		msg.id = imc->ipmsgid;
1619		msg.audit = imc->ipaudit;
1620		memcpy(msg.rmmsg, imc->iprmmsg, 8);
1621		msg.class = imc->ipsrccls;
1622		msg.tag = imc->ipmsgtag;
1623		msg.length = imc->ipbfln2f;
1624		path->handler->message_complete(path, &msg);
1625	}
1626}
1627
1628struct iucv_message_pending {
1629	u16 ippathid;
1630	u8  ipflags1;
1631	u8  iptype;
1632	u32 ipmsgid;
1633	u32 iptrgcls;
1634	struct {
1635		union {
1636			u32 iprmmsg1_u32;
1637			u8  iprmmsg1[4];
1638		} ln1msg1;
1639		union {
1640			u32 ipbfln1f;
1641			u8  iprmmsg2[4];
1642		} ln1msg2;
1643	} rmmsg;
1644	u32 res1[3];
1645	u32 ipbfln2f;
1646	u8  ippollfg;
1647	u8  res2[3];
1648} __packed;
1649
1650/**
1651 * iucv_message_pending
1652 * @data: Pointer to external interrupt buffer
1653 *
1654 * Process message pending work item. Called from tasklet while holding
1655 * iucv_table_lock.
1656 */
1657static void iucv_message_pending(struct iucv_irq_data *data)
1658{
1659	struct iucv_message_pending *imp = (void *) data;
1660	struct iucv_path *path = iucv_path_table[imp->ippathid];
1661	struct iucv_message msg;
1662
1663	if (path && path->handler && path->handler->message_pending) {
1664		msg.flags = imp->ipflags1;
1665		msg.id = imp->ipmsgid;
1666		msg.class = imp->iptrgcls;
1667		if (imp->ipflags1 & IUCV_IPRMDATA) {
1668			memcpy(msg.rmmsg, &imp->rmmsg, 8);
1669			msg.length = 8;
1670		} else
1671			msg.length = imp->rmmsg.ln1msg2.ipbfln1f;
1672		msg.reply_size = imp->ipbfln2f;
1673		path->handler->message_pending(path, &msg);
1674	}
1675}
1676
1677/*
1678 * iucv_tasklet_fn:
1679 *
1680 * This tasklet loops over the queue of irq buffers created by
1681 * iucv_external_interrupt, calls the appropriate action handler
1682 * and then frees the buffer.
1683 */
1684static void iucv_tasklet_fn(unsigned long ignored)
1685{
1686	typedef void iucv_irq_fn(struct iucv_irq_data *);
1687	static iucv_irq_fn *irq_fn[] = {
1688		[0x02] = iucv_path_complete,
1689		[0x03] = iucv_path_severed,
1690		[0x04] = iucv_path_quiesced,
1691		[0x05] = iucv_path_resumed,
1692		[0x06] = iucv_message_complete,
1693		[0x07] = iucv_message_complete,
1694		[0x08] = iucv_message_pending,
1695		[0x09] = iucv_message_pending,
1696	};
1697	LIST_HEAD(task_queue);
1698	struct iucv_irq_list *p, *n;
1699
1700	/* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1701	if (!spin_trylock(&iucv_table_lock)) {
1702		tasklet_schedule(&iucv_tasklet);
1703		return;
1704	}
1705	iucv_active_cpu = smp_processor_id();
1706
1707	spin_lock_irq(&iucv_queue_lock);
1708	list_splice_init(&iucv_task_queue, &task_queue);
1709	spin_unlock_irq(&iucv_queue_lock);
1710
1711	list_for_each_entry_safe(p, n, &task_queue, list) {
1712		list_del_init(&p->list);
1713		irq_fn[p->data.iptype](&p->data);
1714		kfree(p);
1715	}
1716
1717	iucv_active_cpu = -1;
1718	spin_unlock(&iucv_table_lock);
1719}
1720
1721/*
1722 * iucv_work_fn:
1723 *
1724 * This work function loops over the queue of path pending irq blocks
1725 * created by iucv_external_interrupt, calls the appropriate action
1726 * handler and then frees the buffer.
1727 */
1728static void iucv_work_fn(struct work_struct *work)
1729{
1730	LIST_HEAD(work_queue);
1731	struct iucv_irq_list *p, *n;
1732
1733	/* Serialize tasklet, iucv_path_sever and iucv_path_connect. */
1734	spin_lock_bh(&iucv_table_lock);
1735	iucv_active_cpu = smp_processor_id();
1736
1737	spin_lock_irq(&iucv_queue_lock);
1738	list_splice_init(&iucv_work_queue, &work_queue);
1739	spin_unlock_irq(&iucv_queue_lock);
1740
1741	iucv_cleanup_queue();
1742	list_for_each_entry_safe(p, n, &work_queue, list) {
1743		list_del_init(&p->list);
1744		iucv_path_pending(&p->data);
1745		kfree(p);
1746	}
1747
1748	iucv_active_cpu = -1;
1749	spin_unlock_bh(&iucv_table_lock);
1750}
1751
1752/*
1753 * iucv_external_interrupt
1754 *
1755 * Handles external interrupts coming in from CP.
1756 * Places the interrupt buffer on a queue and schedules iucv_tasklet_fn().
1757 */
1758static void iucv_external_interrupt(struct ext_code ext_code,
1759				    unsigned int param32, unsigned long param64)
1760{
1761	struct iucv_irq_data *p;
1762	struct iucv_irq_list *work;
1763
1764	inc_irq_stat(IRQEXT_IUC);
1765	p = iucv_irq_data[smp_processor_id()];
1766	if (p->ippathid >= iucv_max_pathid) {
1767		WARN_ON(p->ippathid >= iucv_max_pathid);
1768		iucv_sever_pathid(p->ippathid, iucv_error_no_listener);
1769		return;
1770	}
1771	BUG_ON(p->iptype  < 0x01 || p->iptype > 0x09);
1772	work = kmalloc(sizeof(struct iucv_irq_list), GFP_ATOMIC);
1773	if (!work) {
1774		pr_warn("iucv_external_interrupt: out of memory\n");
1775		return;
1776	}
1777	memcpy(&work->data, p, sizeof(work->data));
1778	spin_lock(&iucv_queue_lock);
1779	if (p->iptype == 0x01) {
1780		/* Path pending interrupt. */
1781		list_add_tail(&work->list, &iucv_work_queue);
1782		schedule_work(&iucv_work);
1783	} else {
1784		/* The other interrupts. */
1785		list_add_tail(&work->list, &iucv_task_queue);
1786		tasklet_schedule(&iucv_tasklet);
1787	}
1788	spin_unlock(&iucv_queue_lock);
1789}
1790
1791struct iucv_interface iucv_if = {
1792	.message_receive = iucv_message_receive,
1793	.__message_receive = __iucv_message_receive,
1794	.message_reply = iucv_message_reply,
1795	.message_reject = iucv_message_reject,
1796	.message_send = iucv_message_send,
1797	.__message_send = __iucv_message_send,
1798	.message_send2way = iucv_message_send2way,
1799	.message_purge = iucv_message_purge,
1800	.path_accept = iucv_path_accept,
1801	.path_connect = iucv_path_connect,
1802	.path_quiesce = iucv_path_quiesce,
1803	.path_resume = iucv_path_resume,
1804	.path_sever = iucv_path_sever,
1805	.iucv_register = iucv_register,
1806	.iucv_unregister = iucv_unregister,
1807	.bus = NULL,
1808	.root = NULL,
1809};
1810EXPORT_SYMBOL(iucv_if);
1811
1812static enum cpuhp_state iucv_online;
1813/**
1814 * iucv_init
1815 *
1816 * Allocates and initializes various data structures.
1817 */
1818static int __init iucv_init(void)
1819{
1820	int rc;
1821
1822	if (!MACHINE_IS_VM) {
1823		rc = -EPROTONOSUPPORT;
1824		goto out;
1825	}
1826	ctl_set_bit(0, 1);
1827	rc = iucv_query_maxconn();
1828	if (rc)
1829		goto out_ctl;
1830	rc = register_external_irq(EXT_IRQ_IUCV, iucv_external_interrupt);
1831	if (rc)
1832		goto out_ctl;
1833	iucv_root = root_device_register("iucv");
1834	if (IS_ERR(iucv_root)) {
1835		rc = PTR_ERR(iucv_root);
1836		goto out_int;
1837	}
1838
1839	rc = cpuhp_setup_state(CPUHP_NET_IUCV_PREPARE, "net/iucv:prepare",
1840			       iucv_cpu_prepare, iucv_cpu_dead);
1841	if (rc)
1842		goto out_dev;
1843	rc = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "net/iucv:online",
1844			       iucv_cpu_online, iucv_cpu_down_prep);
1845	if (rc < 0)
1846		goto out_prep;
1847	iucv_online = rc;
1848
1849	rc = register_reboot_notifier(&iucv_reboot_notifier);
1850	if (rc)
1851		goto out_remove_hp;
1852	ASCEBC(iucv_error_no_listener, 16);
1853	ASCEBC(iucv_error_no_memory, 16);
1854	ASCEBC(iucv_error_pathid, 16);
1855	iucv_available = 1;
1856	rc = bus_register(&iucv_bus);
1857	if (rc)
1858		goto out_reboot;
1859	iucv_if.root = iucv_root;
1860	iucv_if.bus = &iucv_bus;
1861	return 0;
1862
1863out_reboot:
1864	unregister_reboot_notifier(&iucv_reboot_notifier);
1865out_remove_hp:
1866	cpuhp_remove_state(iucv_online);
1867out_prep:
1868	cpuhp_remove_state(CPUHP_NET_IUCV_PREPARE);
1869out_dev:
1870	root_device_unregister(iucv_root);
1871out_int:
1872	unregister_external_irq(EXT_IRQ_IUCV, iucv_external_interrupt);
1873out_ctl:
1874	ctl_clear_bit(0, 1);
1875out:
1876	return rc;
1877}
1878
1879/**
1880 * iucv_exit
1881 *
1882 * Frees everything allocated from iucv_init.
1883 */
1884static void __exit iucv_exit(void)
1885{
1886	struct iucv_irq_list *p, *n;
1887
1888	spin_lock_irq(&iucv_queue_lock);
1889	list_for_each_entry_safe(p, n, &iucv_task_queue, list)
1890		kfree(p);
1891	list_for_each_entry_safe(p, n, &iucv_work_queue, list)
1892		kfree(p);
1893	spin_unlock_irq(&iucv_queue_lock);
1894	unregister_reboot_notifier(&iucv_reboot_notifier);
1895
1896	cpuhp_remove_state_nocalls(iucv_online);
1897	cpuhp_remove_state(CPUHP_NET_IUCV_PREPARE);
1898	root_device_unregister(iucv_root);
1899	bus_unregister(&iucv_bus);
1900	unregister_external_irq(EXT_IRQ_IUCV, iucv_external_interrupt);
1901}
1902
1903subsys_initcall(iucv_init);
1904module_exit(iucv_exit);
1905
1906MODULE_AUTHOR("(C) 2001 IBM Corp. by Fritz Elfert (felfert@millenux.com)");
1907MODULE_DESCRIPTION("Linux for S/390 IUCV lowlevel driver");
1908MODULE_LICENSE("GPL");
1909