xref: /openbmc/linux/drivers/s390/char/sclp_cpi_sys.c (revision 643d1f7f)
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 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/stat.h>
13 #include <linux/device.h>
14 #include <linux/string.h>
15 #include <linux/ctype.h>
16 #include <linux/kmod.h>
17 #include <linux/timer.h>
18 #include <linux/err.h>
19 #include <linux/slab.h>
20 #include <linux/completion.h>
21 #include <asm/ebcdic.h>
22 #include <asm/sclp.h>
23 #include "sclp.h"
24 #include "sclp_rw.h"
25 #include "sclp_cpi_sys.h"
26 
27 #define CPI_LENGTH_NAME 8
28 #define CPI_LENGTH_LEVEL 16
29 
30 struct cpi_evbuf {
31 	struct evbuf_header header;
32 	u8	id_format;
33 	u8	reserved0;
34 	u8	system_type[CPI_LENGTH_NAME];
35 	u64	reserved1;
36 	u8	system_name[CPI_LENGTH_NAME];
37 	u64	reserved2;
38 	u64	system_level;
39 	u64	reserved3;
40 	u8	sysplex_name[CPI_LENGTH_NAME];
41 	u8	reserved4[16];
42 } __attribute__((packed));
43 
44 struct cpi_sccb {
45 	struct sccb_header header;
46 	struct cpi_evbuf cpi_evbuf;
47 } __attribute__((packed));
48 
49 static struct sclp_register sclp_cpi_event = {
50 	.send_mask = EVTYP_CTLPROGIDENT_MASK,
51 };
52 
53 static char system_name[CPI_LENGTH_NAME + 1];
54 static char sysplex_name[CPI_LENGTH_NAME + 1];
55 static char system_type[CPI_LENGTH_NAME + 1];
56 static u64 system_level;
57 
58 static void set_data(char *field, char *data)
59 {
60 	memset(field, ' ', CPI_LENGTH_NAME);
61 	memcpy(field, data, strlen(data));
62 	sclp_ascebc_str(field, CPI_LENGTH_NAME);
63 }
64 
65 static void cpi_callback(struct sclp_req *req, void *data)
66 {
67 	struct completion *completion = data;
68 
69 	complete(completion);
70 }
71 
72 static struct sclp_req *cpi_prepare_req(void)
73 {
74 	struct sclp_req *req;
75 	struct cpi_sccb *sccb;
76 	struct cpi_evbuf *evb;
77 
78 	req = kzalloc(sizeof(struct sclp_req), GFP_KERNEL);
79 	if (!req)
80 		return ERR_PTR(-ENOMEM);
81 	sccb = (struct cpi_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
82 	if (!sccb) {
83 		kfree(req);
84 		return ERR_PTR(-ENOMEM);
85 	}
86 
87 	/* setup SCCB for Control-Program Identification */
88 	sccb->header.length = sizeof(struct cpi_sccb);
89 	sccb->cpi_evbuf.header.length = sizeof(struct cpi_evbuf);
90 	sccb->cpi_evbuf.header.type = 0x0b;
91 	evb = &sccb->cpi_evbuf;
92 
93 	/* set system type */
94 	set_data(evb->system_type, system_type);
95 
96 	/* set system name */
97 	set_data(evb->system_name, system_name);
98 
99 	/* set sytem level */
100 	evb->system_level = system_level;
101 
102 	/* set sysplex name */
103 	set_data(evb->sysplex_name, sysplex_name);
104 
105 	/* prepare request data structure presented to SCLP driver */
106 	req->command = SCLP_CMDW_WRITE_EVENT_DATA;
107 	req->sccb = sccb;
108 	req->status = SCLP_REQ_FILLED;
109 	req->callback = cpi_callback;
110 	return req;
111 }
112 
113 static void cpi_free_req(struct sclp_req *req)
114 {
115 	free_page((unsigned long) req->sccb);
116 	kfree(req);
117 }
118 
119 static int cpi_req(void)
120 {
121 	struct completion completion;
122 	struct sclp_req *req;
123 	int rc;
124 	int response;
125 
126 	rc = sclp_register(&sclp_cpi_event);
127 	if (rc) {
128 		printk(KERN_WARNING "cpi: could not register "
129 			"to hardware console.\n");
130 		goto out;
131 	}
132 	if (!(sclp_cpi_event.sclp_send_mask & EVTYP_CTLPROGIDENT_MASK)) {
133 		printk(KERN_WARNING "cpi: no control program "
134 			"identification support\n");
135 		rc = -EOPNOTSUPP;
136 		goto out_unregister;
137 	}
138 
139 	req = cpi_prepare_req();
140 	if (IS_ERR(req)) {
141 		printk(KERN_WARNING "cpi: could not allocate request\n");
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 		printk(KERN_WARNING "cpi: could not start request\n");
153 		goto out_free_req;
154 	}
155 
156 	wait_for_completion(&completion);
157 
158 	if (req->status != SCLP_REQ_DONE) {
159 		printk(KERN_WARNING "cpi: request failed (status=0x%02x)\n",
160 			req->status);
161 		rc = -EIO;
162 		goto out_free_req;
163 	}
164 
165 	response = ((struct cpi_sccb *) req->sccb)->header.response_code;
166 	if (response != 0x0020) {
167 		printk(KERN_WARNING "cpi: failed with "
168 			"response code 0x%x\n", response);
169 		rc = -EIO;
170 	}
171 
172 out_free_req:
173 	cpi_free_req(req);
174 
175 out_unregister:
176 	sclp_unregister(&sclp_cpi_event);
177 
178 out:
179 	return rc;
180 }
181 
182 static int check_string(const char *attr, const char *str)
183 {
184 	size_t len;
185 	size_t i;
186 
187 	len = strlen(str);
188 
189 	if ((len > 0) && (str[len - 1] == '\n'))
190 		len--;
191 
192 	if (len > CPI_LENGTH_NAME)
193 		return -EINVAL;
194 
195 	for (i = 0; i < len ; i++) {
196 		if (isalpha(str[i]) || isdigit(str[i]) ||
197 		    strchr("$@# ", str[i]))
198 			continue;
199 		return -EINVAL;
200 	}
201 
202 	return 0;
203 }
204 
205 static void set_string(char *attr, const char *value)
206 {
207 	size_t len;
208 	size_t i;
209 
210 	len = strlen(value);
211 
212 	if ((len > 0) && (value[len - 1] == '\n'))
213 		len--;
214 
215 	for (i = 0; i < CPI_LENGTH_NAME; i++) {
216 		if (i < len)
217 			attr[i] = toupper(value[i]);
218 		else
219 			attr[i] = ' ';
220 	}
221 }
222 
223 static ssize_t system_name_show(struct kobject *kobj,
224 				struct kobj_attribute *attr, char *page)
225 {
226 	return snprintf(page, PAGE_SIZE, "%s\n", system_name);
227 }
228 
229 static ssize_t system_name_store(struct kobject *kobj,
230 				 struct kobj_attribute *attr,
231 				 const char *buf,
232 	size_t len)
233 {
234 	int rc;
235 
236 	rc = check_string("system_name", buf);
237 	if (rc)
238 		return rc;
239 
240 	set_string(system_name, buf);
241 
242 	return len;
243 }
244 
245 static struct kobj_attribute system_name_attr =
246 	__ATTR(system_name, 0644, system_name_show, system_name_store);
247 
248 static ssize_t sysplex_name_show(struct kobject *kobj,
249 				 struct kobj_attribute *attr, char *page)
250 {
251 	return snprintf(page, PAGE_SIZE, "%s\n", sysplex_name);
252 }
253 
254 static ssize_t sysplex_name_store(struct kobject *kobj,
255 				  struct kobj_attribute *attr,
256 				  const char *buf,
257 	size_t len)
258 {
259 	int rc;
260 
261 	rc = check_string("sysplex_name", buf);
262 	if (rc)
263 		return rc;
264 
265 	set_string(sysplex_name, buf);
266 
267 	return len;
268 }
269 
270 static struct kobj_attribute sysplex_name_attr =
271 	__ATTR(sysplex_name, 0644, sysplex_name_show, sysplex_name_store);
272 
273 static ssize_t system_type_show(struct kobject *kobj,
274 				struct kobj_attribute *attr, char *page)
275 {
276 	return snprintf(page, PAGE_SIZE, "%s\n", system_type);
277 }
278 
279 static ssize_t system_type_store(struct kobject *kobj,
280 				 struct kobj_attribute *attr,
281 				 const char *buf,
282 	size_t len)
283 {
284 	int rc;
285 
286 	rc = check_string("system_type", buf);
287 	if (rc)
288 		return rc;
289 
290 	set_string(system_type, buf);
291 
292 	return len;
293 }
294 
295 static struct kobj_attribute system_type_attr =
296 	__ATTR(system_type, 0644, system_type_show, system_type_store);
297 
298 static ssize_t system_level_show(struct kobject *kobj,
299 				 struct kobj_attribute *attr, char *page)
300 {
301 	unsigned long long level = system_level;
302 
303 	return snprintf(page, PAGE_SIZE, "%#018llx\n", level);
304 }
305 
306 static ssize_t system_level_store(struct kobject *kobj,
307 				  struct kobj_attribute *attr,
308 				  const char *buf,
309 	size_t len)
310 {
311 	unsigned long long level;
312 	char *endp;
313 
314 	level = simple_strtoull(buf, &endp, 16);
315 
316 	if (endp == buf)
317 		return -EINVAL;
318 	if (*endp == '\n')
319 		endp++;
320 	if (*endp)
321 		return -EINVAL;
322 
323 	system_level = level;
324 
325 	return len;
326 }
327 
328 static struct kobj_attribute system_level_attr =
329 	__ATTR(system_level, 0644, system_level_show, system_level_store);
330 
331 static ssize_t set_store(struct kobject *kobj,
332 			 struct kobj_attribute *attr,
333 			 const char *buf, size_t len)
334 {
335 	int rc;
336 
337 	rc = cpi_req();
338 	if (rc)
339 		return rc;
340 
341 	return len;
342 }
343 
344 static struct kobj_attribute set_attr = __ATTR(set, 0200, NULL, set_store);
345 
346 static struct attribute *cpi_attrs[] = {
347 	&system_name_attr.attr,
348 	&sysplex_name_attr.attr,
349 	&system_type_attr.attr,
350 	&system_level_attr.attr,
351 	&set_attr.attr,
352 	NULL,
353 };
354 
355 static struct attribute_group cpi_attr_group = {
356 	.attrs = cpi_attrs,
357 };
358 
359 static struct kset *cpi_kset;
360 
361 int sclp_cpi_set_data(const char *system, const char *sysplex, const char *type,
362 		      const u64 level)
363 {
364 	int rc;
365 
366 	rc = check_string("system_name", system);
367 	if (rc)
368 		return rc;
369 	rc = check_string("sysplex_name", sysplex);
370 	if (rc)
371 		return rc;
372 	rc = check_string("system_type", type);
373 	if (rc)
374 		return rc;
375 
376 	set_string(system_name, system);
377 	set_string(sysplex_name, sysplex);
378 	set_string(system_type, type);
379 	system_level = level;
380 
381 	return cpi_req();
382 }
383 EXPORT_SYMBOL(sclp_cpi_set_data);
384 
385 static int __init cpi_init(void)
386 {
387 	int rc;
388 
389 	cpi_kset = kset_create_and_add("cpi", NULL, firmware_kobj);
390 	if (!cpi_kset)
391 		return -ENOMEM;
392 
393 	rc = sysfs_create_group(&cpi_kset->kobj, &cpi_attr_group);
394 	if (rc)
395 		kset_unregister(cpi_kset);
396 
397 	return rc;
398 }
399 
400 __initcall(cpi_init);
401