xref: /linux/include/net/iucv/iucv.h (revision c7546e2c3cb739a3c1a2f5acaf9bb629d401afe5)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  drivers/s390/net/iucv.h
4  *    IUCV base support.
5  *
6  *  S390 version
7  *    Copyright 2000, 2006 IBM Corporation
8  *    Author(s):Alan Altmark (Alan_Altmark@us.ibm.com)
9  *		Xenia Tkatschow (xenia@us.ibm.com)
10  *    Rewritten for af_iucv:
11  *	Martin Schwidefsky <schwidefsky@de.ibm.com>
12  *
13  *
14  * Functionality:
15  * To explore any of the IUCV functions, one must first register their
16  * program using iucv_register(). Once your program has successfully
17  * completed a register, it can exploit the other functions.
18  * For further reference on all IUCV functionality, refer to the
19  * CP Programming Services book, also available on the web thru
20  * www.vm.ibm.com/pubs, manual # SC24-6084
21  *
22  * Definition of Return Codes
23  * - All positive return codes including zero are reflected back
24  *   from CP. The definition of each return code can be found in
25  *   CP Programming Services book.
26  * - Return Code of:
27  *   -EINVAL: Invalid value
28  *   -ENOMEM: storage allocation failed
29  */
30 
31 #include <linux/types.h>
32 #include <linux/slab.h>
33 #include <asm/dma-types.h>
34 #include <asm/debug.h>
35 
36 /*
37  * IUCV option flags usable by device drivers:
38  *
39  * IUCV_IPRMDATA  Indicates that your program can handle a message in the
40  *		  parameter list / a message is sent in the parameter list.
41  *		  Used for iucv_path_accept, iucv_path_connect,
42  *		  iucv_message_reply, iucv_message_send, iucv_message_send2way.
43  * IUCV_IPQUSCE	  Indicates that you do not want to receive messages on this
44  *		  path until an iucv_path_resume is issued.
45  *		  Used for iucv_path_accept, iucv_path_connect.
46  * IUCV_IPBUFLST  Indicates that an address list is used for the message data.
47  *		  Used for iucv_message_receive, iucv_message_send,
48  *		  iucv_message_send2way.
49  * IUCV_IPPRTY	  Specifies that you want to send priority messages.
50  *		  Used for iucv_path_accept, iucv_path_connect,
51  *		  iucv_message_reply, iucv_message_send, iucv_message_send2way.
52  * IUCV_IPSYNC	  Indicates a synchronous send request.
53  *		  Used for iucv_message_send, iucv_message_send2way.
54  * IUCV_IPANSLST  Indicates that an address list is used for the reply data.
55  *		  Used for iucv_message_reply, iucv_message_send2way.
56  * IUCV_IPLOCAL	  Specifies that the communication partner has to be on the
57  *		  local system. If local is specified no target class can be
58  *		  specified.
59  *		  Used for iucv_path_connect.
60  *
61  * All flags are defined in the input field IPFLAGS1 of each function
62  * and can be found in CP Programming Services.
63  */
64 #define IUCV_IPRMDATA	0x80
65 #define IUCV_IPQUSCE	0x40
66 #define IUCV_IPBUFLST	0x40
67 #define IUCV_IPPRTY	0x20
68 #define IUCV_IPANSLST	0x08
69 #define IUCV_IPSYNC	0x04
70 #define IUCV_IPLOCAL	0x01
71 
72 /*
73  * iucv_array : Defines buffer array.
74  * Inside the array may be 31- bit addresses and 31-bit lengths.
75  * Use a pointer to an iucv_array as the buffer, reply or answer
76  * parameter on iucv_message_send, iucv_message_send2way, iucv_message_receive
77  * and iucv_message_reply if IUCV_IPBUFLST or IUCV_IPANSLST are used.
78  */
79 struct iucv_array {
80 	dma32_t address;
81 	u32 length;
82 } __attribute__ ((aligned (8)));
83 
84 extern const struct bus_type iucv_bus;
85 
86 struct device_driver;
87 
88 struct device *iucv_alloc_device(const struct attribute_group **attrs,
89 				 struct device_driver *driver, void *priv,
90 				 const char *fmt, ...) __printf(4, 5);
91 
92 /*
93  * struct iucv_path
94  * pathid: 16 bit path identification
95  * msglim: 16 bit message limit
96  * flags: properties of the path: IPRMDATA, IPQUSCE, IPPRTY
97  * handler:  address of iucv handler structure
98  * private: private information of the handler associated with the path
99  * list: list_head for the iucv_handler path list.
100  */
101 struct iucv_path {
102 	u16 pathid;
103 	u16 msglim;
104 	u8  flags;
105 	void *private;
106 	struct iucv_handler *handler;
107 	struct list_head list;
108 };
109 
110 /*
111  * struct iucv_message
112  * id: 32 bit message id
113  * audit: 32 bit error information of purged or replied messages
114  * class: 32 bit target class of a message (source class for replies)
115  * tag: 32 bit tag to be associated with the message
116  * length: 32 bit length of the message / reply
117  * reply_size: 32 bit maximum allowed length of the reply
118  * rmmsg: 8 byte inline message
119  * flags: message properties (IUCV_IPPRTY)
120  */
121 struct iucv_message {
122 	u32 id;
123 	u32 audit;
124 	u32 class;
125 	u32 tag;
126 	u32 length;
127 	u32 reply_size;
128 	u8  rmmsg[8];
129 	u8  flags;
130 } __packed;
131 
132 /*
133  * struct iucv_handler
134  *
135  * A vector of functions that handle IUCV interrupts. Each functions gets
136  * a parameter area as defined by the CP Programming Services and private
137  * pointer that is provided by the user of the interface.
138  */
139 struct iucv_handler {
140 	 /*
141 	  * The path_pending function is called after an iucv interrupt
142 	  * type 0x01 has been received. The base code allocates a path
143 	  * structure and "asks" the handler if this path belongs to the
144 	  * handler. To accept the path the path_pending function needs
145 	  * to call iucv_path_accept and return 0. If the callback returns
146 	  * a value != 0 the iucv base code will continue with the next
147 	  * handler. The order in which the path_pending functions are
148 	  * called is the order of the registration of the iucv handlers
149 	  * to the base code.
150 	  */
151 	int  (*path_pending)(struct iucv_path *, u8 *ipvmid, u8 *ipuser);
152 	/*
153 	 * The path_complete function is called after an iucv interrupt
154 	 * type 0x02 has been received for a path that has been established
155 	 * for this handler with iucv_path_connect and got accepted by the
156 	 * peer with iucv_path_accept.
157 	 */
158 	void (*path_complete)(struct iucv_path *, u8 *ipuser);
159 	 /*
160 	  * The path_severed function is called after an iucv interrupt
161 	  * type 0x03 has been received. The communication peer shutdown
162 	  * his end of the communication path. The path still exists and
163 	  * remaining messages can be received until a iucv_path_sever
164 	  * shuts down the other end of the path as well.
165 	  */
166 	void (*path_severed)(struct iucv_path *, u8 *ipuser);
167 	/*
168 	 * The path_quiesced function is called after an icuv interrupt
169 	 * type 0x04 has been received. The communication peer has quiesced
170 	 * the path. Delivery of messages is stopped until iucv_path_resume
171 	 * has been called.
172 	 */
173 	void (*path_quiesced)(struct iucv_path *, u8 *ipuser);
174 	/*
175 	 * The path_resumed function is called after an icuv interrupt
176 	 * type 0x05 has been received. The communication peer has resumed
177 	 * the path.
178 	 */
179 	void (*path_resumed)(struct iucv_path *, u8 *ipuser);
180 	/*
181 	 * The message_pending function is called after an icuv interrupt
182 	 * type 0x06 or type 0x07 has been received. A new message is
183 	 * available and can be received with iucv_message_receive.
184 	 */
185 	void (*message_pending)(struct iucv_path *, struct iucv_message *);
186 	/*
187 	 * The message_complete function is called after an icuv interrupt
188 	 * type 0x08 or type 0x09 has been received. A message send with
189 	 * iucv_message_send2way has been replied to. The reply can be
190 	 * received with iucv_message_receive.
191 	 */
192 	void (*message_complete)(struct iucv_path *, struct iucv_message *);
193 
194 	struct list_head list;
195 	struct list_head paths;
196 };
197 
198 /**
199  * iucv_register:
200  * @handler: address of iucv handler structure
201  * @smp: != 0 indicates that the handler can deal with out of order messages
202  *
203  * Registers a driver with IUCV.
204  *
205  * Returns 0 on success, -ENOMEM if the memory allocation for the pathid
206  * table failed, or -EIO if IUCV_DECLARE_BUFFER failed on all cpus.
207  */
208 int iucv_register(struct iucv_handler *handler, int smp);
209 
210 /**
211  * iucv_unregister
212  * @handler:  address of iucv handler structure
213  * @smp: != 0 indicates that the handler can deal with out of order messages
214  *
215  * Unregister driver from IUCV.
216  */
217 void iucv_unregister(struct iucv_handler *handle, int smp);
218 
219 /**
220  * iucv_path_alloc
221  * @msglim: initial message limit
222  * @flags: initial flags
223  * @gfp: kmalloc allocation flag
224  *
225  * Allocate a new path structure for use with iucv_connect.
226  *
227  * Returns NULL if the memory allocation failed or a pointer to the
228  * path structure.
229  */
230 static inline struct iucv_path *iucv_path_alloc(u16 msglim, u8 flags, gfp_t gfp)
231 {
232 	struct iucv_path *path;
233 
234 	path = kzalloc(sizeof(struct iucv_path), gfp);
235 	if (path) {
236 		path->msglim = msglim;
237 		path->flags = flags;
238 	}
239 	return path;
240 }
241 
242 /**
243  * iucv_path_free
244  * @path: address of iucv path structure
245  *
246  * Frees a path structure.
247  */
248 static inline void iucv_path_free(struct iucv_path *path)
249 {
250 	kfree(path);
251 }
252 
253 /**
254  * iucv_path_accept
255  * @path: address of iucv path structure
256  * @handler: address of iucv handler structure
257  * @userdata: 16 bytes of data reflected to the communication partner
258  * @private: private data passed to interrupt handlers for this path
259  *
260  * This function is issued after the user received a connection pending
261  * external interrupt and now wishes to complete the IUCV communication path.
262  *
263  * Returns the result of the CP IUCV call.
264  */
265 int iucv_path_accept(struct iucv_path *path, struct iucv_handler *handler,
266 		     u8 *userdata, void *private);
267 
268 /**
269  * iucv_path_connect
270  * @path: address of iucv path structure
271  * @handler: address of iucv handler structure
272  * @userid: 8-byte user identification
273  * @system: 8-byte target system identification
274  * @userdata: 16 bytes of data reflected to the communication partner
275  * @private: private data passed to interrupt handlers for this path
276  *
277  * This function establishes an IUCV path. Although the connect may complete
278  * successfully, you are not able to use the path until you receive an IUCV
279  * Connection Complete external interrupt.
280  *
281  * Returns the result of the CP IUCV call.
282  */
283 int iucv_path_connect(struct iucv_path *path, struct iucv_handler *handler,
284 		      u8 *userid, u8 *system, u8 *userdata,
285 		      void *private);
286 
287 /**
288  * iucv_path_quiesce:
289  * @path: address of iucv path structure
290  * @userdata: 16 bytes of data reflected to the communication partner
291  *
292  * This function temporarily suspends incoming messages on an IUCV path.
293  * You can later reactivate the path by invoking the iucv_resume function.
294  *
295  * Returns the result from the CP IUCV call.
296  */
297 int iucv_path_quiesce(struct iucv_path *path, u8 *userdata);
298 
299 /**
300  * iucv_path_resume:
301  * @path: address of iucv path structure
302  * @userdata: 16 bytes of data reflected to the communication partner
303  *
304  * This function resumes incoming messages on an IUCV path that has
305  * been stopped with iucv_path_quiesce.
306  *
307  * Returns the result from the CP IUCV call.
308  */
309 int iucv_path_resume(struct iucv_path *path, u8 *userdata);
310 
311 /**
312  * iucv_path_sever
313  * @path: address of iucv path structure
314  * @userdata: 16 bytes of data reflected to the communication partner
315  *
316  * This function terminates an IUCV path.
317  *
318  * Returns the result from the CP IUCV call.
319  */
320 int iucv_path_sever(struct iucv_path *path, u8 *userdata);
321 
322 /**
323  * iucv_message_purge
324  * @path: address of iucv path structure
325  * @msg: address of iucv msg structure
326  * @srccls: source class of message
327  *
328  * Cancels a message you have sent.
329  *
330  * Returns the result from the CP IUCV call.
331  */
332 int iucv_message_purge(struct iucv_path *path, struct iucv_message *msg,
333 		       u32 srccls);
334 
335 /**
336  * iucv_message_receive
337  * @path: address of iucv path structure
338  * @msg: address of iucv msg structure
339  * @flags: flags that affect how the message is received (IUCV_IPBUFLST)
340  * @buffer: address of data buffer or address of struct iucv_array
341  * @size: length of data buffer
342  * @residual:
343  *
344  * This function receives messages that are being sent to you over
345  * established paths. This function will deal with RMDATA messages
346  * embedded in struct iucv_message as well.
347  *
348  * Locking:	local_bh_enable/local_bh_disable
349  *
350  * Returns the result from the CP IUCV call.
351  */
352 int iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
353 			 u8 flags, void *buffer, size_t size, size_t *residual);
354 
355 /**
356  * __iucv_message_receive
357  * @path: address of iucv path structure
358  * @msg: address of iucv msg structure
359  * @flags: flags that affect how the message is received (IUCV_IPBUFLST)
360  * @buffer: address of data buffer or address of struct iucv_array
361  * @size: length of data buffer
362  * @residual:
363  *
364  * This function receives messages that are being sent to you over
365  * established paths. This function will deal with RMDATA messages
366  * embedded in struct iucv_message as well.
367  *
368  * Locking:	no locking.
369  *
370  * Returns the result from the CP IUCV call.
371  */
372 int __iucv_message_receive(struct iucv_path *path, struct iucv_message *msg,
373 			   u8 flags, void *buffer, size_t size,
374 			   size_t *residual);
375 
376 /**
377  * iucv_message_reject
378  * @path: address of iucv path structure
379  * @msg: address of iucv msg structure
380  *
381  * The reject function refuses a specified message. Between the time you
382  * are notified of a message and the time that you complete the message,
383  * the message may be rejected.
384  *
385  * Returns the result from the CP IUCV call.
386  */
387 int iucv_message_reject(struct iucv_path *path, struct iucv_message *msg);
388 
389 /**
390  * iucv_message_reply
391  * @path: address of iucv path structure
392  * @msg: address of iucv msg structure
393  * @flags: how the reply is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
394  * @reply: address of data buffer or address of struct iucv_array
395  * @size: length of reply data buffer
396  *
397  * This function responds to the two-way messages that you receive. You
398  * must identify completely the message to which you wish to reply. ie,
399  * pathid, msgid, and trgcls. Prmmsg signifies the data is moved into
400  * the parameter list.
401  *
402  * Returns the result from the CP IUCV call.
403  */
404 int iucv_message_reply(struct iucv_path *path, struct iucv_message *msg,
405 		       u8 flags, void *reply, size_t size);
406 
407 /**
408  * iucv_message_send
409  * @path: address of iucv path structure
410  * @msg: address of iucv msg structure
411  * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
412  * @srccls: source class of message
413  * @buffer: address of data buffer or address of struct iucv_array
414  * @size: length of send buffer
415  *
416  * This function transmits data to another application. Data to be
417  * transmitted is in a buffer and this is a one-way message and the
418  * receiver will not reply to the message.
419  *
420  * Locking:	local_bh_enable/local_bh_disable
421  *
422  * Returns the result from the CP IUCV call.
423  */
424 int iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
425 		      u8 flags, u32 srccls, void *buffer, size_t size);
426 
427 /**
428  * __iucv_message_send
429  * @path: address of iucv path structure
430  * @msg: address of iucv msg structure
431  * @flags: how the message is sent (IUCV_IPRMDATA, IUCV_IPPRTY, IUCV_IPBUFLST)
432  * @srccls: source class of message
433  * @buffer: address of data buffer or address of struct iucv_array
434  * @size: length of send buffer
435  *
436  * This function transmits data to another application. Data to be
437  * transmitted is in a buffer and this is a one-way message and the
438  * receiver will not reply to the message.
439  *
440  * Locking:	no locking.
441  *
442  * Returns the result from the CP IUCV call.
443  */
444 int __iucv_message_send(struct iucv_path *path, struct iucv_message *msg,
445 			u8 flags, u32 srccls, void *buffer, size_t size);
446 
447 /**
448  * iucv_message_send2way
449  * @path: address of iucv path structure
450  * @msg: address of iucv msg structure
451  * @flags: how the message is sent and the reply is received
452  *	   (IUCV_IPRMDATA, IUCV_IPBUFLST, IUCV_IPPRTY, IUCV_ANSLST)
453  * @srccls: source class of message
454  * @buffer: address of data buffer or address of struct iucv_array
455  * @size: length of send buffer
456  * @ansbuf: address of answer buffer or address of struct iucv_array
457  * @asize: size of reply buffer
458  *
459  * This function transmits data to another application. Data to be
460  * transmitted is in a buffer. The receiver of the send is expected to
461  * reply to the message and a buffer is provided into which IUCV moves
462  * the reply to this message.
463  *
464  * Returns the result from the CP IUCV call.
465  */
466 int iucv_message_send2way(struct iucv_path *path, struct iucv_message *msg,
467 			  u8 flags, u32 srccls, void *buffer, size_t size,
468 			  void *answer, size_t asize, size_t *residual);
469 
470 struct iucv_interface {
471 	int (*message_receive)(struct iucv_path *path, struct iucv_message *msg,
472 		u8 flags, void *buffer, size_t size, size_t *residual);
473 	int (*__message_receive)(struct iucv_path *path,
474 		struct iucv_message *msg, u8 flags, void *buffer, size_t size,
475 		size_t *residual);
476 	int (*message_reply)(struct iucv_path *path, struct iucv_message *msg,
477 		u8 flags, void *reply, size_t size);
478 	int (*message_reject)(struct iucv_path *path, struct iucv_message *msg);
479 	int (*message_send)(struct iucv_path *path, struct iucv_message *msg,
480 		u8 flags, u32 srccls, void *buffer, size_t size);
481 	int (*__message_send)(struct iucv_path *path, struct iucv_message *msg,
482 		u8 flags, u32 srccls, void *buffer, size_t size);
483 	int (*message_send2way)(struct iucv_path *path,
484 		struct iucv_message *msg, u8 flags, u32 srccls, void *buffer,
485 		size_t size, void *answer, size_t asize, size_t *residual);
486 	int (*message_purge)(struct iucv_path *path, struct iucv_message *msg,
487 		u32 srccls);
488 	int (*path_accept)(struct iucv_path *path, struct iucv_handler *handler,
489 		u8 userdata[16], void *private);
490 	int (*path_connect)(struct iucv_path *path,
491 		struct iucv_handler *handler,
492 		u8 userid[8], u8 system[8], u8 userdata[16], void *private);
493 	int (*path_quiesce)(struct iucv_path *path, u8 userdata[16]);
494 	int (*path_resume)(struct iucv_path *path, u8 userdata[16]);
495 	int (*path_sever)(struct iucv_path *path, u8 userdata[16]);
496 	int (*iucv_register)(struct iucv_handler *handler, int smp);
497 	void (*iucv_unregister)(struct iucv_handler *handler, int smp);
498 	const struct bus_type *bus;
499 	struct device *root;
500 };
501 
502 extern struct iucv_interface iucv_if;
503