drivers/s390/char/sclp_cpi_sys.c

   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_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);