drivers/s390/char/sclp_cpi_sys.c

   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);