xref: /openbmc/linux/drivers/s390/char/sclp_cpi_sys.c (revision 63dc02bd)
1 /*
2  *  drivers/s390/char/sclp_cpi_sys.c
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 
35 static DEFINE_MUTEX(sclp_cpi_mutex);
36 
37 struct 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 
51 struct cpi_sccb {
52 	struct sccb_header header;
53 	struct cpi_evbuf cpi_evbuf;
54 } __attribute__((packed));
55 
56 static struct sclp_register sclp_cpi_event = {
57 	.send_mask = EVTYP_CTLPROGIDENT_MASK,
58 };
59 
60 static char system_name[CPI_LENGTH_NAME + 1];
61 static char sysplex_name[CPI_LENGTH_NAME + 1];
62 static char system_type[CPI_LENGTH_NAME + 1];
63 static u64 system_level;
64 
65 static 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 
72 static void cpi_callback(struct sclp_req *req, void *data)
73 {
74 	struct completion *completion = data;
75 
76 	complete(completion);
77 }
78 
79 static 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 = 0x0b;
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 
120 static void cpi_free_req(struct sclp_req *req)
121 {
122 	free_page((unsigned long) req->sccb);
123 	kfree(req);
124 }
125 
126 static 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_warning("request failed (status=0x%02x)\n",
159 			   req->status);
160 		rc = -EIO;
161 		goto out_free_req;
162 	}
163 
164 	response = ((struct cpi_sccb *) req->sccb)->header.response_code;
165 	if (response != 0x0020) {
166 		pr_warning("request failed with response code 0x%x\n",
167 			   response);
168 		rc = -EIO;
169 	}
170 
171 out_free_req:
172 	cpi_free_req(req);
173 
174 out_unregister:
175 	sclp_unregister(&sclp_cpi_event);
176 
177 out:
178 	return rc;
179 }
180 
181 static int check_string(const char *attr, const char *str)
182 {
183 	size_t len;
184 	size_t i;
185 
186 	len = strlen(str);
187 
188 	if ((len > 0) && (str[len - 1] == '\n'))
189 		len--;
190 
191 	if (len > CPI_LENGTH_NAME)
192 		return -EINVAL;
193 
194 	for (i = 0; i < len ; i++) {
195 		if (isalpha(str[i]) || isdigit(str[i]) ||
196 		    strchr("$@# ", str[i]))
197 			continue;
198 		return -EINVAL;
199 	}
200 
201 	return 0;
202 }
203 
204 static void set_string(char *attr, const char *value)
205 {
206 	size_t len;
207 	size_t i;
208 
209 	len = strlen(value);
210 
211 	if ((len > 0) && (value[len - 1] == '\n'))
212 		len--;
213 
214 	for (i = 0; i < CPI_LENGTH_NAME; i++) {
215 		if (i < len)
216 			attr[i] = toupper(value[i]);
217 		else
218 			attr[i] = ' ';
219 	}
220 }
221 
222 static ssize_t system_name_show(struct kobject *kobj,
223 				struct kobj_attribute *attr, char *page)
224 {
225 	int rc;
226 
227 	mutex_lock(&sclp_cpi_mutex);
228 	rc = snprintf(page, PAGE_SIZE, "%s\n", system_name);
229 	mutex_unlock(&sclp_cpi_mutex);
230 	return rc;
231 }
232 
233 static ssize_t system_name_store(struct kobject *kobj,
234 				 struct kobj_attribute *attr,
235 				 const char *buf,
236 	size_t len)
237 {
238 	int rc;
239 
240 	rc = check_string("system_name", buf);
241 	if (rc)
242 		return rc;
243 
244 	mutex_lock(&sclp_cpi_mutex);
245 	set_string(system_name, buf);
246 	mutex_unlock(&sclp_cpi_mutex);
247 
248 	return len;
249 }
250 
251 static struct kobj_attribute system_name_attr =
252 	__ATTR(system_name, 0644, system_name_show, system_name_store);
253 
254 static ssize_t sysplex_name_show(struct kobject *kobj,
255 				 struct kobj_attribute *attr, char *page)
256 {
257 	int rc;
258 
259 	mutex_lock(&sclp_cpi_mutex);
260 	rc = snprintf(page, PAGE_SIZE, "%s\n", sysplex_name);
261 	mutex_unlock(&sclp_cpi_mutex);
262 	return rc;
263 }
264 
265 static ssize_t sysplex_name_store(struct kobject *kobj,
266 				  struct kobj_attribute *attr,
267 				  const char *buf,
268 	size_t len)
269 {
270 	int rc;
271 
272 	rc = check_string("sysplex_name", buf);
273 	if (rc)
274 		return rc;
275 
276 	mutex_lock(&sclp_cpi_mutex);
277 	set_string(sysplex_name, buf);
278 	mutex_unlock(&sclp_cpi_mutex);
279 
280 	return len;
281 }
282 
283 static struct kobj_attribute sysplex_name_attr =
284 	__ATTR(sysplex_name, 0644, sysplex_name_show, sysplex_name_store);
285 
286 static ssize_t system_type_show(struct kobject *kobj,
287 				struct kobj_attribute *attr, char *page)
288 {
289 	int rc;
290 
291 	mutex_lock(&sclp_cpi_mutex);
292 	rc = snprintf(page, PAGE_SIZE, "%s\n", system_type);
293 	mutex_unlock(&sclp_cpi_mutex);
294 	return rc;
295 }
296 
297 static ssize_t system_type_store(struct kobject *kobj,
298 				 struct kobj_attribute *attr,
299 				 const char *buf,
300 	size_t len)
301 {
302 	int rc;
303 
304 	rc = check_string("system_type", buf);
305 	if (rc)
306 		return rc;
307 
308 	mutex_lock(&sclp_cpi_mutex);
309 	set_string(system_type, buf);
310 	mutex_unlock(&sclp_cpi_mutex);
311 
312 	return len;
313 }
314 
315 static struct kobj_attribute system_type_attr =
316 	__ATTR(system_type, 0644, system_type_show, system_type_store);
317 
318 static ssize_t system_level_show(struct kobject *kobj,
319 				 struct kobj_attribute *attr, char *page)
320 {
321 	unsigned long long level;
322 
323 	mutex_lock(&sclp_cpi_mutex);
324 	level = system_level;
325 	mutex_unlock(&sclp_cpi_mutex);
326 	return snprintf(page, PAGE_SIZE, "%#018llx\n", level);
327 }
328 
329 static ssize_t system_level_store(struct kobject *kobj,
330 				  struct kobj_attribute *attr,
331 				  const char *buf,
332 	size_t len)
333 {
334 	unsigned long long level;
335 	char *endp;
336 
337 	level = simple_strtoull(buf, &endp, 16);
338 
339 	if (endp == buf)
340 		return -EINVAL;
341 	if (*endp == '\n')
342 		endp++;
343 	if (*endp)
344 		return -EINVAL;
345 
346 	mutex_lock(&sclp_cpi_mutex);
347 	system_level = level;
348 	mutex_unlock(&sclp_cpi_mutex);
349 	return len;
350 }
351 
352 static struct kobj_attribute system_level_attr =
353 	__ATTR(system_level, 0644, system_level_show, system_level_store);
354 
355 static ssize_t set_store(struct kobject *kobj,
356 			 struct kobj_attribute *attr,
357 			 const char *buf, size_t len)
358 {
359 	int rc;
360 
361 	mutex_lock(&sclp_cpi_mutex);
362 	rc = cpi_req();
363 	mutex_unlock(&sclp_cpi_mutex);
364 	if (rc)
365 		return rc;
366 
367 	return len;
368 }
369 
370 static struct kobj_attribute set_attr = __ATTR(set, 0200, NULL, set_store);
371 
372 static struct attribute *cpi_attrs[] = {
373 	&system_name_attr.attr,
374 	&sysplex_name_attr.attr,
375 	&system_type_attr.attr,
376 	&system_level_attr.attr,
377 	&set_attr.attr,
378 	NULL,
379 };
380 
381 static struct attribute_group cpi_attr_group = {
382 	.attrs = cpi_attrs,
383 };
384 
385 static struct kset *cpi_kset;
386 
387 int sclp_cpi_set_data(const char *system, const char *sysplex, const char *type,
388 		      const u64 level)
389 {
390 	int rc;
391 
392 	rc = check_string("system_name", system);
393 	if (rc)
394 		return rc;
395 	rc = check_string("sysplex_name", sysplex);
396 	if (rc)
397 		return rc;
398 	rc = check_string("system_type", type);
399 	if (rc)
400 		return rc;
401 
402 	mutex_lock(&sclp_cpi_mutex);
403 	set_string(system_name, system);
404 	set_string(sysplex_name, sysplex);
405 	set_string(system_type, type);
406 	system_level = level;
407 
408 	rc = cpi_req();
409 	mutex_unlock(&sclp_cpi_mutex);
410 
411 	return rc;
412 }
413 EXPORT_SYMBOL(sclp_cpi_set_data);
414 
415 static int __init cpi_init(void)
416 {
417 	int rc;
418 
419 	cpi_kset = kset_create_and_add("cpi", NULL, firmware_kobj);
420 	if (!cpi_kset)
421 		return -ENOMEM;
422 
423 	rc = sysfs_create_group(&cpi_kset->kobj, &cpi_attr_group);
424 	if (rc)
425 		kset_unregister(cpi_kset);
426 
427 	return rc;
428 }
429 
430 __initcall(cpi_init);
431