1// SPDX-License-Identifier: GPL-2.0
2/*
3 *    SCLP control program identification sysfs interface
4 *
5 *    Copyright IBM Corp. 2001, 2007
6 *    Author(s): Martin Peschke <mpeschke@de.ibm.com>
7 *		 Michael Ernst <mernst@de.ibm.com>
8 */
9
10#define KMSG_COMPONENT "sclp_cpi"
11#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/stat.h>
16#include <linux/device.h>
17#include <linux/string.h>
18#include <linux/ctype.h>
19#include <linux/kmod.h>
20#include <linux/timer.h>
21#include <linux/err.h>
22#include <linux/slab.h>
23#include <linux/completion.h>
24#include <linux/export.h>
25#include <asm/ebcdic.h>
26#include <asm/sclp.h>
27
28#include "sclp.h"
29#include "sclp_rw.h"
30#include "sclp_cpi_sys.h"
31
32#define CPI_LENGTH_NAME 8
33#define CPI_LENGTH_LEVEL 16
34
35static DEFINE_MUTEX(sclp_cpi_mutex);
36
37struct cpi_evbuf {
38	struct evbuf_header header;
39	u8	id_format;
40	u8	reserved0;
41	u8	system_type[CPI_LENGTH_NAME];
42	u64	reserved1;
43	u8	system_name[CPI_LENGTH_NAME];
44	u64	reserved2;
45	u64	system_level;
46	u64	reserved3;
47	u8	sysplex_name[CPI_LENGTH_NAME];
48	u8	reserved4[16];
49} __attribute__((packed));
50
51struct cpi_sccb {
52	struct sccb_header header;
53	struct cpi_evbuf cpi_evbuf;
54} __attribute__((packed));
55
56static struct sclp_register sclp_cpi_event = {
57	.send_mask = EVTYP_CTLPROGIDENT_MASK,
58};
59
60static char system_name[CPI_LENGTH_NAME + 1];
61static char sysplex_name[CPI_LENGTH_NAME + 1];
62static char system_type[CPI_LENGTH_NAME + 1];
63static u64 system_level;
64
65static void set_data(char *field, char *data)
66{
67	memset(field, ' ', CPI_LENGTH_NAME);
68	memcpy(field, data, strlen(data));
69	sclp_ascebc_str(field, CPI_LENGTH_NAME);
70}
71
72static void cpi_callback(struct sclp_req *req, void *data)
73{
74	struct completion *completion = data;
75
76	complete(completion);
77}
78
79static struct sclp_req *cpi_prepare_req(void)
80{
81	struct sclp_req *req;
82	struct cpi_sccb *sccb;
83	struct cpi_evbuf *evb;
84
85	req = kzalloc(sizeof(struct sclp_req), GFP_KERNEL);
86	if (!req)
87		return ERR_PTR(-ENOMEM);
88	sccb = (struct cpi_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
89	if (!sccb) {
90		kfree(req);
91		return ERR_PTR(-ENOMEM);
92	}
93
94	/* setup SCCB for Control-Program Identification */
95	sccb->header.length = sizeof(struct cpi_sccb);
96	sccb->cpi_evbuf.header.length = sizeof(struct cpi_evbuf);
97	sccb->cpi_evbuf.header.type = EVTYP_CTLPROGIDENT;
98	evb = &sccb->cpi_evbuf;
99
100	/* set system type */
101	set_data(evb->system_type, system_type);
102
103	/* set system name */
104	set_data(evb->system_name, system_name);
105
106	/* set system level */
107	evb->system_level = system_level;
108
109	/* set sysplex name */
110	set_data(evb->sysplex_name, sysplex_name);
111
112	/* prepare request data structure presented to SCLP driver */
113	req->command = SCLP_CMDW_WRITE_EVENT_DATA;
114	req->sccb = sccb;
115	req->status = SCLP_REQ_FILLED;
116	req->callback = cpi_callback;
117	return req;
118}
119
120static void cpi_free_req(struct sclp_req *req)
121{
122	free_page((unsigned long) req->sccb);
123	kfree(req);
124}
125
126static int cpi_req(void)
127{
128	struct completion completion;
129	struct sclp_req *req;
130	int rc;
131	int response;
132
133	rc = sclp_register(&sclp_cpi_event);
134	if (rc)
135		goto out;
136	if (!(sclp_cpi_event.sclp_receive_mask & EVTYP_CTLPROGIDENT_MASK)) {
137		rc = -EOPNOTSUPP;
138		goto out_unregister;
139	}
140
141	req = cpi_prepare_req();
142	if (IS_ERR(req)) {
143		rc = PTR_ERR(req);
144		goto out_unregister;
145	}
146
147	init_completion(&completion);
148	req->callback_data = &completion;
149
150	/* Add request to sclp queue */
151	rc = sclp_add_request(req);
152	if (rc)
153		goto out_free_req;
154
155	wait_for_completion(&completion);
156
157	if (req->status != SCLP_REQ_DONE) {
158		pr_warn("request failed (status=0x%02x)\n", req->status);
159		rc = -EIO;
160		goto out_free_req;
161	}
162
163	response = ((struct cpi_sccb *) req->sccb)->header.response_code;
164	if (response != 0x0020) {
165		pr_warn("request failed with response code 0x%x\n", response);
166		rc = -EIO;
167	}
168
169out_free_req:
170	cpi_free_req(req);
171
172out_unregister:
173	sclp_unregister(&sclp_cpi_event);
174
175out:
176	return rc;
177}
178
179static int check_string(const char *attr, const char *str)
180{
181	size_t len;
182	size_t i;
183
184	len = strlen(str);
185
186	if ((len > 0) && (str[len - 1] == '\n'))
187		len--;
188
189	if (len > CPI_LENGTH_NAME)
190		return -EINVAL;
191
192	for (i = 0; i < len ; i++) {
193		if (isalpha(str[i]) || isdigit(str[i]) ||
194		    strchr("$@# ", str[i]))
195			continue;
196		return -EINVAL;
197	}
198
199	return 0;
200}
201
202static void set_string(char *attr, const char *value)
203{
204	size_t len;
205	size_t i;
206
207	len = strlen(value);
208
209	if ((len > 0) && (value[len - 1] == '\n'))
210		len--;
211
212	for (i = 0; i < CPI_LENGTH_NAME; i++) {
213		if (i < len)
214			attr[i] = toupper(value[i]);
215		else
216			attr[i] = ' ';
217	}
218}
219
220static ssize_t system_name_show(struct kobject *kobj,
221				struct kobj_attribute *attr, char *page)
222{
223	int rc;
224
225	mutex_lock(&sclp_cpi_mutex);
226	rc = snprintf(page, PAGE_SIZE, "%s\n", system_name);
227	mutex_unlock(&sclp_cpi_mutex);
228	return rc;
229}
230
231static ssize_t system_name_store(struct kobject *kobj,
232				 struct kobj_attribute *attr,
233				 const char *buf,
234	size_t len)
235{
236	int rc;
237
238	rc = check_string("system_name", buf);
239	if (rc)
240		return rc;
241
242	mutex_lock(&sclp_cpi_mutex);
243	set_string(system_name, buf);
244	mutex_unlock(&sclp_cpi_mutex);
245
246	return len;
247}
248
249static struct kobj_attribute system_name_attr =
250	__ATTR(system_name, 0644, system_name_show, system_name_store);
251
252static ssize_t sysplex_name_show(struct kobject *kobj,
253				 struct kobj_attribute *attr, char *page)
254{
255	int rc;
256
257	mutex_lock(&sclp_cpi_mutex);
258	rc = snprintf(page, PAGE_SIZE, "%s\n", sysplex_name);
259	mutex_unlock(&sclp_cpi_mutex);
260	return rc;
261}
262
263static ssize_t sysplex_name_store(struct kobject *kobj,
264				  struct kobj_attribute *attr,
265				  const char *buf,
266	size_t len)
267{
268	int rc;
269
270	rc = check_string("sysplex_name", buf);
271	if (rc)
272		return rc;
273
274	mutex_lock(&sclp_cpi_mutex);
275	set_string(sysplex_name, buf);
276	mutex_unlock(&sclp_cpi_mutex);
277
278	return len;
279}
280
281static struct kobj_attribute sysplex_name_attr =
282	__ATTR(sysplex_name, 0644, sysplex_name_show, sysplex_name_store);
283
284static ssize_t system_type_show(struct kobject *kobj,
285				struct kobj_attribute *attr, char *page)
286{
287	int rc;
288
289	mutex_lock(&sclp_cpi_mutex);
290	rc = snprintf(page, PAGE_SIZE, "%s\n", system_type);
291	mutex_unlock(&sclp_cpi_mutex);
292	return rc;
293}
294
295static ssize_t system_type_store(struct kobject *kobj,
296				 struct kobj_attribute *attr,
297				 const char *buf,
298	size_t len)
299{
300	int rc;
301
302	rc = check_string("system_type", buf);
303	if (rc)
304		return rc;
305
306	mutex_lock(&sclp_cpi_mutex);
307	set_string(system_type, buf);
308	mutex_unlock(&sclp_cpi_mutex);
309
310	return len;
311}
312
313static struct kobj_attribute system_type_attr =
314	__ATTR(system_type, 0644, system_type_show, system_type_store);
315
316static ssize_t system_level_show(struct kobject *kobj,
317				 struct kobj_attribute *attr, char *page)
318{
319	unsigned long long level;
320
321	mutex_lock(&sclp_cpi_mutex);
322	level = system_level;
323	mutex_unlock(&sclp_cpi_mutex);
324	return snprintf(page, PAGE_SIZE, "%#018llx\n", level);
325}
326
327static ssize_t system_level_store(struct kobject *kobj,
328				  struct kobj_attribute *attr,
329				  const char *buf,
330	size_t len)
331{
332	unsigned long long level;
333	char *endp;
334
335	level = simple_strtoull(buf, &endp, 16);
336
337	if (endp == buf)
338		return -EINVAL;
339	if (*endp == '\n')
340		endp++;
341	if (*endp)
342		return -EINVAL;
343
344	mutex_lock(&sclp_cpi_mutex);
345	system_level = level;
346	mutex_unlock(&sclp_cpi_mutex);
347	return len;
348}
349
350static struct kobj_attribute system_level_attr =
351	__ATTR(system_level, 0644, system_level_show, system_level_store);
352
353static ssize_t set_store(struct kobject *kobj,
354			 struct kobj_attribute *attr,
355			 const char *buf, size_t len)
356{
357	int rc;
358
359	mutex_lock(&sclp_cpi_mutex);
360	rc = cpi_req();
361	mutex_unlock(&sclp_cpi_mutex);
362	if (rc)
363		return rc;
364
365	return len;
366}
367
368static struct kobj_attribute set_attr = __ATTR(set, 0200, NULL, set_store);
369
370static struct attribute *cpi_attrs[] = {
371	&system_name_attr.attr,
372	&sysplex_name_attr.attr,
373	&system_type_attr.attr,
374	&system_level_attr.attr,
375	&set_attr.attr,
376	NULL,
377};
378
379static struct attribute_group cpi_attr_group = {
380	.attrs = cpi_attrs,
381};
382
383static struct kset *cpi_kset;
384
385int sclp_cpi_set_data(const char *system, const char *sysplex, const char *type,
386		      const u64 level)
387{
388	int rc;
389
390	rc = check_string("system_name", system);
391	if (rc)
392		return rc;
393	rc = check_string("sysplex_name", sysplex);
394	if (rc)
395		return rc;
396	rc = check_string("system_type", type);
397	if (rc)
398		return rc;
399
400	mutex_lock(&sclp_cpi_mutex);
401	set_string(system_name, system);
402	set_string(sysplex_name, sysplex);
403	set_string(system_type, type);
404	system_level = level;
405
406	rc = cpi_req();
407	mutex_unlock(&sclp_cpi_mutex);
408
409	return rc;
410}
411EXPORT_SYMBOL(sclp_cpi_set_data);
412
413static int __init cpi_init(void)
414{
415	int rc;
416
417	cpi_kset = kset_create_and_add("cpi", NULL, firmware_kobj);
418	if (!cpi_kset)
419		return -ENOMEM;
420
421	rc = sysfs_create_group(&cpi_kset->kobj, &cpi_attr_group);
422	if (rc)
423		kset_unregister(cpi_kset);
424
425	return rc;
426}
427
428__initcall(cpi_init);
429