xref: /openbmc/linux/drivers/s390/char/sclp_cpi_sys.c (revision bc5aa3a0)
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 = EVTYP_CTLPROGIDENT;
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_warn("request failed (status=0x%02x)\n", req->status);
158 		rc = -EIO;
159 		goto out_free_req;
160 	}
161 
162 	response = ((struct cpi_sccb *) req->sccb)->header.response_code;
163 	if (response != 0x0020) {
164 		pr_warn("request failed with response code 0x%x\n", response);
165 		rc = -EIO;
166 	}
167 
168 out_free_req:
169 	cpi_free_req(req);
170 
171 out_unregister:
172 	sclp_unregister(&sclp_cpi_event);
173 
174 out:
175 	return rc;
176 }
177 
178 static int check_string(const char *attr, const char *str)
179 {
180 	size_t len;
181 	size_t i;
182 
183 	len = strlen(str);
184 
185 	if ((len > 0) && (str[len - 1] == '\n'))
186 		len--;
187 
188 	if (len > CPI_LENGTH_NAME)
189 		return -EINVAL;
190 
191 	for (i = 0; i < len ; i++) {
192 		if (isalpha(str[i]) || isdigit(str[i]) ||
193 		    strchr("$@# ", str[i]))
194 			continue;
195 		return -EINVAL;
196 	}
197 
198 	return 0;
199 }
200 
201 static void set_string(char *attr, const char *value)
202 {
203 	size_t len;
204 	size_t i;
205 
206 	len = strlen(value);
207 
208 	if ((len > 0) && (value[len - 1] == '\n'))
209 		len--;
210 
211 	for (i = 0; i < CPI_LENGTH_NAME; i++) {
212 		if (i < len)
213 			attr[i] = toupper(value[i]);
214 		else
215 			attr[i] = ' ';
216 	}
217 }
218 
219 static ssize_t system_name_show(struct kobject *kobj,
220 				struct kobj_attribute *attr, char *page)
221 {
222 	int rc;
223 
224 	mutex_lock(&sclp_cpi_mutex);
225 	rc = snprintf(page, PAGE_SIZE, "%s\n", system_name);
226 	mutex_unlock(&sclp_cpi_mutex);
227 	return rc;
228 }
229 
230 static ssize_t system_name_store(struct kobject *kobj,
231 				 struct kobj_attribute *attr,
232 				 const char *buf,
233 	size_t len)
234 {
235 	int rc;
236 
237 	rc = check_string("system_name", buf);
238 	if (rc)
239 		return rc;
240 
241 	mutex_lock(&sclp_cpi_mutex);
242 	set_string(system_name, buf);
243 	mutex_unlock(&sclp_cpi_mutex);
244 
245 	return len;
246 }
247 
248 static struct kobj_attribute system_name_attr =
249 	__ATTR(system_name, 0644, system_name_show, system_name_store);
250 
251 static ssize_t sysplex_name_show(struct kobject *kobj,
252 				 struct kobj_attribute *attr, char *page)
253 {
254 	int rc;
255 
256 	mutex_lock(&sclp_cpi_mutex);
257 	rc = snprintf(page, PAGE_SIZE, "%s\n", sysplex_name);
258 	mutex_unlock(&sclp_cpi_mutex);
259 	return rc;
260 }
261 
262 static ssize_t sysplex_name_store(struct kobject *kobj,
263 				  struct kobj_attribute *attr,
264 				  const char *buf,
265 	size_t len)
266 {
267 	int rc;
268 
269 	rc = check_string("sysplex_name", buf);
270 	if (rc)
271 		return rc;
272 
273 	mutex_lock(&sclp_cpi_mutex);
274 	set_string(sysplex_name, buf);
275 	mutex_unlock(&sclp_cpi_mutex);
276 
277 	return len;
278 }
279 
280 static struct kobj_attribute sysplex_name_attr =
281 	__ATTR(sysplex_name, 0644, sysplex_name_show, sysplex_name_store);
282 
283 static ssize_t system_type_show(struct kobject *kobj,
284 				struct kobj_attribute *attr, char *page)
285 {
286 	int rc;
287 
288 	mutex_lock(&sclp_cpi_mutex);
289 	rc = snprintf(page, PAGE_SIZE, "%s\n", system_type);
290 	mutex_unlock(&sclp_cpi_mutex);
291 	return rc;
292 }
293 
294 static ssize_t system_type_store(struct kobject *kobj,
295 				 struct kobj_attribute *attr,
296 				 const char *buf,
297 	size_t len)
298 {
299 	int rc;
300 
301 	rc = check_string("system_type", buf);
302 	if (rc)
303 		return rc;
304 
305 	mutex_lock(&sclp_cpi_mutex);
306 	set_string(system_type, buf);
307 	mutex_unlock(&sclp_cpi_mutex);
308 
309 	return len;
310 }
311 
312 static struct kobj_attribute system_type_attr =
313 	__ATTR(system_type, 0644, system_type_show, system_type_store);
314 
315 static ssize_t system_level_show(struct kobject *kobj,
316 				 struct kobj_attribute *attr, char *page)
317 {
318 	unsigned long long level;
319 
320 	mutex_lock(&sclp_cpi_mutex);
321 	level = system_level;
322 	mutex_unlock(&sclp_cpi_mutex);
323 	return snprintf(page, PAGE_SIZE, "%#018llx\n", level);
324 }
325 
326 static ssize_t system_level_store(struct kobject *kobj,
327 				  struct kobj_attribute *attr,
328 				  const char *buf,
329 	size_t len)
330 {
331 	unsigned long long level;
332 	char *endp;
333 
334 	level = simple_strtoull(buf, &endp, 16);
335 
336 	if (endp == buf)
337 		return -EINVAL;
338 	if (*endp == '\n')
339 		endp++;
340 	if (*endp)
341 		return -EINVAL;
342 
343 	mutex_lock(&sclp_cpi_mutex);
344 	system_level = level;
345 	mutex_unlock(&sclp_cpi_mutex);
346 	return len;
347 }
348 
349 static struct kobj_attribute system_level_attr =
350 	__ATTR(system_level, 0644, system_level_show, system_level_store);
351 
352 static ssize_t set_store(struct kobject *kobj,
353 			 struct kobj_attribute *attr,
354 			 const char *buf, size_t len)
355 {
356 	int rc;
357 
358 	mutex_lock(&sclp_cpi_mutex);
359 	rc = cpi_req();
360 	mutex_unlock(&sclp_cpi_mutex);
361 	if (rc)
362 		return rc;
363 
364 	return len;
365 }
366 
367 static struct kobj_attribute set_attr = __ATTR(set, 0200, NULL, set_store);
368 
369 static struct attribute *cpi_attrs[] = {
370 	&system_name_attr.attr,
371 	&sysplex_name_attr.attr,
372 	&system_type_attr.attr,
373 	&system_level_attr.attr,
374 	&set_attr.attr,
375 	NULL,
376 };
377 
378 static struct attribute_group cpi_attr_group = {
379 	.attrs = cpi_attrs,
380 };
381 
382 static struct kset *cpi_kset;
383 
384 int sclp_cpi_set_data(const char *system, const char *sysplex, const char *type,
385 		      const u64 level)
386 {
387 	int rc;
388 
389 	rc = check_string("system_name", system);
390 	if (rc)
391 		return rc;
392 	rc = check_string("sysplex_name", sysplex);
393 	if (rc)
394 		return rc;
395 	rc = check_string("system_type", type);
396 	if (rc)
397 		return rc;
398 
399 	mutex_lock(&sclp_cpi_mutex);
400 	set_string(system_name, system);
401 	set_string(sysplex_name, sysplex);
402 	set_string(system_type, type);
403 	system_level = level;
404 
405 	rc = cpi_req();
406 	mutex_unlock(&sclp_cpi_mutex);
407 
408 	return rc;
409 }
410 EXPORT_SYMBOL(sclp_cpi_set_data);
411 
412 static int __init cpi_init(void)
413 {
414 	int rc;
415 
416 	cpi_kset = kset_create_and_add("cpi", NULL, firmware_kobj);
417 	if (!cpi_kset)
418 		return -ENOMEM;
419 
420 	rc = sysfs_create_group(&cpi_kset->kobj, &cpi_attr_group);
421 	if (rc)
422 		kset_unregister(cpi_kset);
423 
424 	return rc;
425 }
426 
427 __initcall(cpi_init);
428