xref: /openbmc/linux/drivers/s390/char/sclp_cpi_sys.c (revision 4f3db074)
1 /*
2  *    SCLP control program identification sysfs interface
3  *
4  *    Copyright IBM Corp. 2001, 2007
5  *    Author(s): Martin Peschke <mpeschke@de.ibm.com>
6  *		 Michael Ernst <mernst@de.ibm.com>
7  */
8 
9 #define KMSG_COMPONENT "sclp_cpi"
10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11 
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/stat.h>
15 #include <linux/device.h>
16 #include <linux/string.h>
17 #include <linux/ctype.h>
18 #include <linux/kmod.h>
19 #include <linux/timer.h>
20 #include <linux/err.h>
21 #include <linux/slab.h>
22 #include <linux/completion.h>
23 #include <linux/export.h>
24 #include <asm/ebcdic.h>
25 #include <asm/sclp.h>
26 
27 #include "sclp.h"
28 #include "sclp_rw.h"
29 #include "sclp_cpi_sys.h"
30 
31 #define CPI_LENGTH_NAME 8
32 #define CPI_LENGTH_LEVEL 16
33 
34 static DEFINE_MUTEX(sclp_cpi_mutex);
35 
36 struct cpi_evbuf {
37 	struct evbuf_header header;
38 	u8	id_format;
39 	u8	reserved0;
40 	u8	system_type[CPI_LENGTH_NAME];
41 	u64	reserved1;
42 	u8	system_name[CPI_LENGTH_NAME];
43 	u64	reserved2;
44 	u64	system_level;
45 	u64	reserved3;
46 	u8	sysplex_name[CPI_LENGTH_NAME];
47 	u8	reserved4[16];
48 } __attribute__((packed));
49 
50 struct cpi_sccb {
51 	struct sccb_header header;
52 	struct cpi_evbuf cpi_evbuf;
53 } __attribute__((packed));
54 
55 static struct sclp_register sclp_cpi_event = {
56 	.send_mask = EVTYP_CTLPROGIDENT_MASK,
57 };
58 
59 static char system_name[CPI_LENGTH_NAME + 1];
60 static char sysplex_name[CPI_LENGTH_NAME + 1];
61 static char system_type[CPI_LENGTH_NAME + 1];
62 static u64 system_level;
63 
64 static void set_data(char *field, char *data)
65 {
66 	memset(field, ' ', CPI_LENGTH_NAME);
67 	memcpy(field, data, strlen(data));
68 	sclp_ascebc_str(field, CPI_LENGTH_NAME);
69 }
70 
71 static void cpi_callback(struct sclp_req *req, void *data)
72 {
73 	struct completion *completion = data;
74 
75 	complete(completion);
76 }
77 
78 static struct sclp_req *cpi_prepare_req(void)
79 {
80 	struct sclp_req *req;
81 	struct cpi_sccb *sccb;
82 	struct cpi_evbuf *evb;
83 
84 	req = kzalloc(sizeof(struct sclp_req), GFP_KERNEL);
85 	if (!req)
86 		return ERR_PTR(-ENOMEM);
87 	sccb = (struct cpi_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
88 	if (!sccb) {
89 		kfree(req);
90 		return ERR_PTR(-ENOMEM);
91 	}
92 
93 	/* setup SCCB for Control-Program Identification */
94 	sccb->header.length = sizeof(struct cpi_sccb);
95 	sccb->cpi_evbuf.header.length = sizeof(struct cpi_evbuf);
96 	sccb->cpi_evbuf.header.type = 0x0b;
97 	evb = &sccb->cpi_evbuf;
98 
99 	/* set system type */
100 	set_data(evb->system_type, system_type);
101 
102 	/* set system name */
103 	set_data(evb->system_name, system_name);
104 
105 	/* set system level */
106 	evb->system_level = system_level;
107 
108 	/* set sysplex name */
109 	set_data(evb->sysplex_name, sysplex_name);
110 
111 	/* prepare request data structure presented to SCLP driver */
112 	req->command = SCLP_CMDW_WRITE_EVENT_DATA;
113 	req->sccb = sccb;
114 	req->status = SCLP_REQ_FILLED;
115 	req->callback = cpi_callback;
116 	return req;
117 }
118 
119 static void cpi_free_req(struct sclp_req *req)
120 {
121 	free_page((unsigned long) req->sccb);
122 	kfree(req);
123 }
124 
125 static int cpi_req(void)
126 {
127 	struct completion completion;
128 	struct sclp_req *req;
129 	int rc;
130 	int response;
131 
132 	rc = sclp_register(&sclp_cpi_event);
133 	if (rc)
134 		goto out;
135 	if (!(sclp_cpi_event.sclp_receive_mask & EVTYP_CTLPROGIDENT_MASK)) {
136 		rc = -EOPNOTSUPP;
137 		goto out_unregister;
138 	}
139 
140 	req = cpi_prepare_req();
141 	if (IS_ERR(req)) {
142 		rc = PTR_ERR(req);
143 		goto out_unregister;
144 	}
145 
146 	init_completion(&completion);
147 	req->callback_data = &completion;
148 
149 	/* Add request to sclp queue */
150 	rc = sclp_add_request(req);
151 	if (rc)
152 		goto out_free_req;
153 
154 	wait_for_completion(&completion);
155 
156 	if (req->status != SCLP_REQ_DONE) {
157 		pr_warning("request failed (status=0x%02x)\n",
158 			   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_warning("request failed with response code 0x%x\n",
166 			   response);
167 		rc = -EIO;
168 	}
169 
170 out_free_req:
171 	cpi_free_req(req);
172 
173 out_unregister:
174 	sclp_unregister(&sclp_cpi_event);
175 
176 out:
177 	return rc;
178 }
179 
180 static int check_string(const char *attr, const char *str)
181 {
182 	size_t len;
183 	size_t i;
184 
185 	len = strlen(str);
186 
187 	if ((len > 0) && (str[len - 1] == '\n'))
188 		len--;
189 
190 	if (len > CPI_LENGTH_NAME)
191 		return -EINVAL;
192 
193 	for (i = 0; i < len ; i++) {
194 		if (isalpha(str[i]) || isdigit(str[i]) ||
195 		    strchr("$@# ", str[i]))
196 			continue;
197 		return -EINVAL;
198 	}
199 
200 	return 0;
201 }
202 
203 static void set_string(char *attr, const char *value)
204 {
205 	size_t len;
206 	size_t i;
207 
208 	len = strlen(value);
209 
210 	if ((len > 0) && (value[len - 1] == '\n'))
211 		len--;
212 
213 	for (i = 0; i < CPI_LENGTH_NAME; i++) {
214 		if (i < len)
215 			attr[i] = toupper(value[i]);
216 		else
217 			attr[i] = ' ';
218 	}
219 }
220 
221 static ssize_t system_name_show(struct kobject *kobj,
222 				struct kobj_attribute *attr, char *page)
223 {
224 	int rc;
225 
226 	mutex_lock(&sclp_cpi_mutex);
227 	rc = snprintf(page, PAGE_SIZE, "%s\n", system_name);
228 	mutex_unlock(&sclp_cpi_mutex);
229 	return rc;
230 }
231 
232 static ssize_t system_name_store(struct kobject *kobj,
233 				 struct kobj_attribute *attr,
234 				 const char *buf,
235 	size_t len)
236 {
237 	int rc;
238 
239 	rc = check_string("system_name", buf);
240 	if (rc)
241 		return rc;
242 
243 	mutex_lock(&sclp_cpi_mutex);
244 	set_string(system_name, buf);
245 	mutex_unlock(&sclp_cpi_mutex);
246 
247 	return len;
248 }
249 
250 static struct kobj_attribute system_name_attr =
251 	__ATTR(system_name, 0644, system_name_show, system_name_store);
252 
253 static ssize_t sysplex_name_show(struct kobject *kobj,
254 				 struct kobj_attribute *attr, char *page)
255 {
256 	int rc;
257 
258 	mutex_lock(&sclp_cpi_mutex);
259 	rc = snprintf(page, PAGE_SIZE, "%s\n", sysplex_name);
260 	mutex_unlock(&sclp_cpi_mutex);
261 	return rc;
262 }
263 
264 static ssize_t sysplex_name_store(struct kobject *kobj,
265 				  struct kobj_attribute *attr,
266 				  const char *buf,
267 	size_t len)
268 {
269 	int rc;
270 
271 	rc = check_string("sysplex_name", buf);
272 	if (rc)
273 		return rc;
274 
275 	mutex_lock(&sclp_cpi_mutex);
276 	set_string(sysplex_name, buf);
277 	mutex_unlock(&sclp_cpi_mutex);
278 
279 	return len;
280 }
281 
282 static struct kobj_attribute sysplex_name_attr =
283 	__ATTR(sysplex_name, 0644, sysplex_name_show, sysplex_name_store);
284 
285 static ssize_t system_type_show(struct kobject *kobj,
286 				struct kobj_attribute *attr, char *page)
287 {
288 	int rc;
289 
290 	mutex_lock(&sclp_cpi_mutex);
291 	rc = snprintf(page, PAGE_SIZE, "%s\n", system_type);
292 	mutex_unlock(&sclp_cpi_mutex);
293 	return rc;
294 }
295 
296 static ssize_t system_type_store(struct kobject *kobj,
297 				 struct kobj_attribute *attr,
298 				 const char *buf,
299 	size_t len)
300 {
301 	int rc;
302 
303 	rc = check_string("system_type", buf);
304 	if (rc)
305 		return rc;
306 
307 	mutex_lock(&sclp_cpi_mutex);
308 	set_string(system_type, buf);
309 	mutex_unlock(&sclp_cpi_mutex);
310 
311 	return len;
312 }
313 
314 static struct kobj_attribute system_type_attr =
315 	__ATTR(system_type, 0644, system_type_show, system_type_store);
316 
317 static ssize_t system_level_show(struct kobject *kobj,
318 				 struct kobj_attribute *attr, char *page)
319 {
320 	unsigned long long level;
321 
322 	mutex_lock(&sclp_cpi_mutex);
323 	level = system_level;
324 	mutex_unlock(&sclp_cpi_mutex);
325 	return snprintf(page, PAGE_SIZE, "%#018llx\n", level);
326 }
327 
328 static ssize_t system_level_store(struct kobject *kobj,
329 				  struct kobj_attribute *attr,
330 				  const char *buf,
331 	size_t len)
332 {
333 	unsigned long long level;
334 	char *endp;
335 
336 	level = simple_strtoull(buf, &endp, 16);
337 
338 	if (endp == buf)
339 		return -EINVAL;
340 	if (*endp == '\n')
341 		endp++;
342 	if (*endp)
343 		return -EINVAL;
344 
345 	mutex_lock(&sclp_cpi_mutex);
346 	system_level = level;
347 	mutex_unlock(&sclp_cpi_mutex);
348 	return len;
349 }
350 
351 static struct kobj_attribute system_level_attr =
352 	__ATTR(system_level, 0644, system_level_show, system_level_store);
353 
354 static ssize_t set_store(struct kobject *kobj,
355 			 struct kobj_attribute *attr,
356 			 const char *buf, size_t len)
357 {
358 	int rc;
359 
360 	mutex_lock(&sclp_cpi_mutex);
361 	rc = cpi_req();
362 	mutex_unlock(&sclp_cpi_mutex);
363 	if (rc)
364 		return rc;
365 
366 	return len;
367 }
368 
369 static struct kobj_attribute set_attr = __ATTR(set, 0200, NULL, set_store);
370 
371 static struct attribute *cpi_attrs[] = {
372 	&system_name_attr.attr,
373 	&sysplex_name_attr.attr,
374 	&system_type_attr.attr,
375 	&system_level_attr.attr,
376 	&set_attr.attr,
377 	NULL,
378 };
379 
380 static struct attribute_group cpi_attr_group = {
381 	.attrs = cpi_attrs,
382 };
383 
384 static struct kset *cpi_kset;
385 
386 int sclp_cpi_set_data(const char *system, const char *sysplex, const char *type,
387 		      const u64 level)
388 {
389 	int rc;
390 
391 	rc = check_string("system_name", system);
392 	if (rc)
393 		return rc;
394 	rc = check_string("sysplex_name", sysplex);
395 	if (rc)
396 		return rc;
397 	rc = check_string("system_type", type);
398 	if (rc)
399 		return rc;
400 
401 	mutex_lock(&sclp_cpi_mutex);
402 	set_string(system_name, system);
403 	set_string(sysplex_name, sysplex);
404 	set_string(system_type, type);
405 	system_level = level;
406 
407 	rc = cpi_req();
408 	mutex_unlock(&sclp_cpi_mutex);
409 
410 	return rc;
411 }
412 EXPORT_SYMBOL(sclp_cpi_set_data);
413 
414 static int __init cpi_init(void)
415 {
416 	int rc;
417 
418 	cpi_kset = kset_create_and_add("cpi", NULL, firmware_kobj);
419 	if (!cpi_kset)
420 		return -ENOMEM;
421 
422 	rc = sysfs_create_group(&cpi_kset->kobj, &cpi_attr_group);
423 	if (rc)
424 		kset_unregister(cpi_kset);
425 
426 	return rc;
427 }
428 
429 __initcall(cpi_init);
430