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 #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_receive_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);