arch/s390/kernel/sthyi.c

   1 /*
   2  * store hypervisor information instruction emulation functions.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License (version 2 only)
   6  * as published by the Free Software Foundation.
   7  *
   8  * Copyright IBM Corp. 2016
   9  * Author(s): Janosch Frank <frankja@linux.vnet.ibm.com>
  10  */
  11 #include <linux/errno.h>
  12 #include <linux/pagemap.h>
  13 #include <linux/vmalloc.h>
  14 #include <linux/syscalls.h>
  15 #include <linux/mutex.h>
  16 #include <asm/asm-offsets.h>
  17 #include <asm/sclp.h>
  18 #include <asm/diag.h>
  19 #include <asm/sysinfo.h>
  20 #include <asm/ebcdic.h>
  21 #include <asm/facility.h>
  22 #include <asm/sthyi.h>
  23 #include "entry.h"
  24
  25 #define DED_WEIGHT 0xffff
  26 /*
  27  * CP and IFL as EBCDIC strings, SP/0x40 determines the end of string
  28  * as they are justified with spaces.
  29  */
  30 #define CP  0xc3d7404040404040UL
  31 #define IFL 0xc9c6d34040404040UL
  32
  33 enum hdr_flags {
  34         HDR_NOT_LPAR   = 0x10,
  35         HDR_STACK_INCM = 0x20,
  36         HDR_STSI_UNAV  = 0x40,
  37         HDR_PERF_UNAV  = 0x80,
  38 };
  39
  40 enum mac_validity {
  41         MAC_NAME_VLD = 0x20,
  42         MAC_ID_VLD   = 0x40,
  43         MAC_CNT_VLD  = 0x80,
  44 };
  45
  46 enum par_flag {
  47         PAR_MT_EN = 0x80,
  48 };
  49
  50 enum par_validity {
  51         PAR_GRP_VLD  = 0x08,
  52         PAR_ID_VLD   = 0x10,
  53         PAR_ABS_VLD  = 0x20,
  54         PAR_WGHT_VLD = 0x40,
  55         PAR_PCNT_VLD  = 0x80,
  56 };
  57
  58 struct hdr_sctn {
  59         u8 infhflg1;
  60         u8 infhflg2; /* reserved */
  61         u8 infhval1; /* reserved */
  62         u8 infhval2; /* reserved */
  63         u8 reserved[3];
  64         u8 infhygct;
  65         u16 infhtotl;
  66         u16 infhdln;
  67         u16 infmoff;
  68         u16 infmlen;
  69         u16 infpoff;
  70         u16 infplen;
  71         u16 infhoff1;
  72         u16 infhlen1;
  73         u16 infgoff1;
  74         u16 infglen1;
  75         u16 infhoff2;
  76         u16 infhlen2;
  77         u16 infgoff2;
  78         u16 infglen2;
  79         u16 infhoff3;
  80         u16 infhlen3;
  81         u16 infgoff3;
  82         u16 infglen3;
  83         u8 reserved2[4];
  84 } __packed;
  85
  86 struct mac_sctn {
  87         u8 infmflg1; /* reserved */
  88         u8 infmflg2; /* reserved */
  89         u8 infmval1;
  90         u8 infmval2; /* reserved */
  91         u16 infmscps;
  92         u16 infmdcps;
  93         u16 infmsifl;
  94         u16 infmdifl;
  95         char infmname[8];
  96         char infmtype[4];
  97         char infmmanu[16];
  98         char infmseq[16];
  99         char infmpman[4];
 100         u8 reserved[4];
 101 } __packed;
 102
 103 struct par_sctn {
 104         u8 infpflg1;
 105         u8 infpflg2; /* reserved */
 106         u8 infpval1;
 107         u8 infpval2; /* reserved */
 108         u16 infppnum;
 109         u16 infpscps;
 110         u16 infpdcps;
 111         u16 infpsifl;
 112         u16 infpdifl;
 113         u16 reserved;
 114         char infppnam[8];
 115         u32 infpwbcp;
 116         u32 infpabcp;
 117         u32 infpwbif;
 118         u32 infpabif;
 119         char infplgnm[8];
 120         u32 infplgcp;
 121         u32 infplgif;
 122 } __packed;
 123
 124 struct sthyi_sctns {
 125         struct hdr_sctn hdr;
 126         struct mac_sctn mac;
 127         struct par_sctn par;
 128 } __packed;
 129
 130 struct cpu_inf {
 131         u64 lpar_cap;
 132         u64 lpar_grp_cap;
 133         u64 lpar_weight;
 134         u64 all_weight;
 135         int cpu_num_ded;
 136         int cpu_num_shd;
 137 };
 138
 139 struct lpar_cpu_inf {
 140         struct cpu_inf cp;
 141         struct cpu_inf ifl;
 142 };
 143
 144 /*
 145  * STHYI requires extensive locking in the higher hypervisors
 146  * and is very computational/memory expensive. Therefore we
 147  * cache the retrieved data whose valid period is 1s.
 148  */
 149 #define CACHE_VALID_JIFFIES     HZ
 150
 151 struct sthyi_info {
 152         void *info;
 153         unsigned long end;
 154 };
 155
 156 static DEFINE_MUTEX(sthyi_mutex);
 157 static struct sthyi_info sthyi_cache;
 158
 159 static inline u64 cpu_id(u8 ctidx, void *diag224_buf)
 160 {
 161         return *((u64 *)(diag224_buf + (ctidx + 1) * DIAG204_CPU_NAME_LEN));
 162 }
 163
 164 /*
 165  * Scales the cpu capping from the lpar range to the one expected in
 166  * sthyi data.
 167  *
 168  * diag204 reports a cap in hundredths of processor units.
 169  * z/VM's range for one core is 0 - 0x10000.
 170  */
 171 static u32 scale_cap(u32 in)
 172 {
 173         return (0x10000 * in) / 100;
 174 }
 175
 176 static void fill_hdr(struct sthyi_sctns *sctns)
 177 {
 178         sctns->hdr.infhdln = sizeof(sctns->hdr);
 179         sctns->hdr.infmoff = sizeof(sctns->hdr);
 180         sctns->hdr.infmlen = sizeof(sctns->mac);
 181         sctns->hdr.infplen = sizeof(sctns->par);
 182         sctns->hdr.infpoff = sctns->hdr.infhdln + sctns->hdr.infmlen;
 183         sctns->hdr.infhtotl = sctns->hdr.infpoff + sctns->hdr.infplen;
 184 }
 185
 186 static void fill_stsi_mac(struct sthyi_sctns *sctns,
 187                           struct sysinfo_1_1_1 *sysinfo)
 188 {
 189         if (stsi(sysinfo, 1, 1, 1))
 190                 return;
 191
 192         sclp_ocf_cpc_name_copy(sctns->mac.infmname);
 193
 194         memcpy(sctns->mac.infmtype, sysinfo->type, sizeof(sctns->mac.infmtype));
 195         memcpy(sctns->mac.infmmanu, sysinfo->manufacturer, sizeof(sctns->mac.infmmanu));
 196         memcpy(sctns->mac.infmpman, sysinfo->plant, sizeof(sctns->mac.infmpman));
 197         memcpy(sctns->mac.infmseq, sysinfo->sequence, sizeof(sctns->mac.infmseq));
 198
 199         sctns->mac.infmval1 |= MAC_ID_VLD | MAC_NAME_VLD;
 200 }
 201
 202 static void fill_stsi_par(struct sthyi_sctns *sctns,
 203                           struct sysinfo_2_2_2 *sysinfo)
 204 {
 205         if (stsi(sysinfo, 2, 2, 2))
 206                 return;
 207
 208         sctns->par.infppnum = sysinfo->lpar_number;
 209         memcpy(sctns->par.infppnam, sysinfo->name, sizeof(sctns->par.infppnam));
 210
 211         sctns->par.infpval1 |= PAR_ID_VLD;
 212 }
 213
 214 static void fill_stsi(struct sthyi_sctns *sctns)
 215 {
 216         void *sysinfo;
 217
 218         /* Errors are handled through the validity bits in the response. */
 219         sysinfo = (void *)__get_free_page(GFP_KERNEL);
 220         if (!sysinfo)
 221                 return;
 222
 223         fill_stsi_mac(sctns, sysinfo);
 224         fill_stsi_par(sctns, sysinfo);
 225
 226         free_pages((unsigned long)sysinfo, 0);
 227 }
 228
 229 static void fill_diag_mac(struct sthyi_sctns *sctns,
 230                           struct diag204_x_phys_block *block,
 231                           void *diag224_buf)
 232 {
 233         int i;
 234
 235         for (i = 0; i < block->hdr.cpus; i++) {
 236                 switch (cpu_id(block->cpus[i].ctidx, diag224_buf)) {
 237                 case CP:
 238                         if (block->cpus[i].weight == DED_WEIGHT)
 239                                 sctns->mac.infmdcps++;
 240                         else
 241                                 sctns->mac.infmscps++;
 242                         break;
 243                 case IFL:
 244                         if (block->cpus[i].weight == DED_WEIGHT)
 245                                 sctns->mac.infmdifl++;
 246                         else
 247                                 sctns->mac.infmsifl++;
 248                         break;
 249                 }
 250         }
 251         sctns->mac.infmval1 |= MAC_CNT_VLD;
 252 }
 253
 254 /* Returns a pointer to the the next partition block. */
 255 static struct diag204_x_part_block *lpar_cpu_inf(struct lpar_cpu_inf *part_inf,
 256                                                  bool this_lpar,
 257                                                  void *diag224_buf,
 258                                                  struct diag204_x_part_block *block)
 259 {
 260         int i, capped = 0, weight_cp = 0, weight_ifl = 0;
 261         struct cpu_inf *cpu_inf;
 262
 263         for (i = 0; i < block->hdr.rcpus; i++) {
 264                 if (!(block->cpus[i].cflag & DIAG204_CPU_ONLINE))
 265                         continue;
 266
 267                 switch (cpu_id(block->cpus[i].ctidx, diag224_buf)) {
 268                 case CP:
 269                         cpu_inf = &part_inf->cp;
 270                         if (block->cpus[i].cur_weight < DED_WEIGHT)
 271                                 weight_cp |= block->cpus[i].cur_weight;
 272                         break;
 273                 case IFL:
 274                         cpu_inf = &part_inf->ifl;
 275                         if (block->cpus[i].cur_weight < DED_WEIGHT)
 276                                 weight_ifl |= block->cpus[i].cur_weight;
 277                         break;
 278                 default:
 279                         continue;
 280                 }
 281
 282                 if (!this_lpar)
 283                         continue;
 284
 285                 capped |= block->cpus[i].cflag & DIAG204_CPU_CAPPED;
 286                 cpu_inf->lpar_cap |= block->cpus[i].cpu_type_cap;
 287                 cpu_inf->lpar_grp_cap |= block->cpus[i].group_cpu_type_cap;
 288
 289                 if (block->cpus[i].weight == DED_WEIGHT)
 290                         cpu_inf->cpu_num_ded += 1;
 291                 else
 292                         cpu_inf->cpu_num_shd += 1;
 293         }
 294
 295         if (this_lpar && capped) {
 296                 part_inf->cp.lpar_weight = weight_cp;
 297                 part_inf->ifl.lpar_weight = weight_ifl;
 298         }
 299         part_inf->cp.all_weight += weight_cp;
 300         part_inf->ifl.all_weight += weight_ifl;
 301         return (struct diag204_x_part_block *)&block->cpus[i];
 302 }
 303
 304 static void fill_diag(struct sthyi_sctns *sctns)
 305 {
 306         int i, r, pages;
 307         bool this_lpar;
 308         void *diag204_buf;
 309         void *diag224_buf = NULL;
 310         struct diag204_x_info_blk_hdr *ti_hdr;
 311         struct diag204_x_part_block *part_block;
 312         struct diag204_x_phys_block *phys_block;
 313         struct lpar_cpu_inf lpar_inf = {};
 314
 315         /* Errors are handled through the validity bits in the response. */
 316         pages = diag204((unsigned long)DIAG204_SUBC_RSI |
 317                         (unsigned long)DIAG204_INFO_EXT, 0, NULL);
 318         if (pages <= 0)
 319                 return;
 320
 321         diag204_buf = vmalloc(PAGE_SIZE * pages);
 322         if (!diag204_buf)
 323                 return;
 324
 325         r = diag204((unsigned long)DIAG204_SUBC_STIB7 |
 326                     (unsigned long)DIAG204_INFO_EXT, pages, diag204_buf);
 327         if (r < 0)
 328                 goto out;
 329
 330         diag224_buf = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
 331         if (!diag224_buf || diag224(diag224_buf))
 332                 goto out;
 333
 334         ti_hdr = diag204_buf;
 335         part_block = diag204_buf + sizeof(*ti_hdr);
 336
 337         for (i = 0; i < ti_hdr->npar; i++) {
 338                 /*
 339                  * For the calling lpar we also need to get the cpu
 340                  * caps and weights. The time information block header
 341                  * specifies the offset to the partition block of the
 342                  * caller lpar, so we know when we process its data.
 343                  */
 344                 this_lpar = (void *)part_block - diag204_buf == ti_hdr->this_part;
 345                 part_block = lpar_cpu_inf(&lpar_inf, this_lpar, diag224_buf,
 346                                           part_block);
 347         }
 348
 349         phys_block = (struct diag204_x_phys_block *)part_block;
 350         part_block = diag204_buf + ti_hdr->this_part;
 351         if (part_block->hdr.mtid)
 352                 sctns->par.infpflg1 = PAR_MT_EN;
 353
 354         sctns->par.infpval1 |= PAR_GRP_VLD;
 355         sctns->par.infplgcp = scale_cap(lpar_inf.cp.lpar_grp_cap);
 356         sctns->par.infplgif = scale_cap(lpar_inf.ifl.lpar_grp_cap);
 357         memcpy(sctns->par.infplgnm, part_block->hdr.hardware_group_name,
 358                sizeof(sctns->par.infplgnm));
 359
 360         sctns->par.infpscps = lpar_inf.cp.cpu_num_shd;
 361         sctns->par.infpdcps = lpar_inf.cp.cpu_num_ded;
 362         sctns->par.infpsifl = lpar_inf.ifl.cpu_num_shd;
 363         sctns->par.infpdifl = lpar_inf.ifl.cpu_num_ded;
 364         sctns->par.infpval1 |= PAR_PCNT_VLD;
 365
 366         sctns->par.infpabcp = scale_cap(lpar_inf.cp.lpar_cap);
 367         sctns->par.infpabif = scale_cap(lpar_inf.ifl.lpar_cap);
 368         sctns->par.infpval1 |= PAR_ABS_VLD;
 369
 370         /*
 371          * Everything below needs global performance data to be
 372          * meaningful.
 373          */
 374         if (!(ti_hdr->flags & DIAG204_LPAR_PHYS_FLG)) {
 375                 sctns->hdr.infhflg1 |= HDR_PERF_UNAV;
 376                 goto out;
 377         }
 378
 379         fill_diag_mac(sctns, phys_block, diag224_buf);
 380
 381         if (lpar_inf.cp.lpar_weight) {
 382                 sctns->par.infpwbcp = sctns->mac.infmscps * 0x10000 *
 383                         lpar_inf.cp.lpar_weight / lpar_inf.cp.all_weight;
 384         }
 385
 386         if (lpar_inf.ifl.lpar_weight) {
 387                 sctns->par.infpwbif = sctns->mac.infmsifl * 0x10000 *
 388                         lpar_inf.ifl.lpar_weight / lpar_inf.ifl.all_weight;
 389         }
 390         sctns->par.infpval1 |= PAR_WGHT_VLD;
 391
 392 out:
 393         free_page((unsigned long)diag224_buf);
 394         vfree(diag204_buf);
 395 }
 396
 397 static int sthyi(u64 vaddr, u64 *rc)
 398 {
 399         register u64 code asm("0") = 0;
 400         register u64 addr asm("2") = vaddr;
 401         register u64 rcode asm("3");
 402         int cc;
 403
 404         asm volatile(
 405                 ".insn   rre,0xB2560000,%[code],%[addr]\n"
 406                 "ipm     %[cc]\n"
 407                 "srl     %[cc],28\n"
 408                 : [cc] "=d" (cc), "=d" (rcode)
 409                 : [code] "d" (code), [addr] "a" (addr)
 410                 : "memory", "cc");
 411         *rc = rcode;
 412         return cc;
 413 }
 414
 415 static int fill_dst(void *dst, u64 *rc)
 416 {
 417         struct sthyi_sctns *sctns = (struct sthyi_sctns *)dst;
 418
 419         /*
 420          * If the facility is on, we don't want to emulate the instruction.
 421          * We ask the hypervisor to provide the data.
 422          */
 423         if (test_facility(74))
 424                 return sthyi((u64)dst, rc);
 425
 426         fill_hdr(sctns);
 427         fill_stsi(sctns);
 428         fill_diag(sctns);
 429         *rc = 0;
 430         return 0;
 431 }
 432
 433 static int sthyi_init_cache(void)
 434 {
 435         if (sthyi_cache.info)
 436                 return 0;
 437         sthyi_cache.info = (void *)get_zeroed_page(GFP_KERNEL);
 438         if (!sthyi_cache.info)
 439                 return -ENOMEM;
 440         sthyi_cache.end = jiffies - 1; /* expired */
 441         return 0;
 442 }
 443
 444 static int sthyi_update_cache(u64 *rc)
 445 {
 446         int r;
 447
 448         memset(sthyi_cache.info, 0, PAGE_SIZE);
 449         r = fill_dst(sthyi_cache.info, rc);
 450         if (r)
 451                 return r;
 452         sthyi_cache.end = jiffies + CACHE_VALID_JIFFIES;
 453         return r;
 454 }
 455
 456 /*
 457  * sthyi_fill - Fill page with data returned by the STHYI instruction
 458  *
 459  * @dst: Pointer to zeroed page
 460  * @rc:  Pointer for storing the return code of the instruction
 461  *
 462  * Fills the destination with system information returned by the STHYI
 463  * instruction. The data is generated by emulation or execution of STHYI,
 464  * if available. The return value is the condition code that would be
 465  * returned, the rc parameter is the return code which is passed in
 466  * register R2 + 1.
 467  */
 468 int sthyi_fill(void *dst, u64 *rc)
 469 {
 470         int r;
 471
 472         mutex_lock(&sthyi_mutex);
 473         r = sthyi_init_cache();
 474         if (r)
 475                 goto out;
 476
 477         if (time_is_before_jiffies(sthyi_cache.end)) {
 478                 /* cache expired */
 479                 r = sthyi_update_cache(rc);
 480                 if (r)
 481                         goto out;
 482         }
 483         *rc = 0;
 484         memcpy(dst, sthyi_cache.info, PAGE_SIZE);
 485 out:
 486         mutex_unlock(&sthyi_mutex);
 487         return r;
 488 }
 489 EXPORT_SYMBOL_GPL(sthyi_fill);
 490
 491 SYSCALL_DEFINE4(s390_sthyi, unsigned long, function_code, void __user *, buffer,
 492                 u64 __user *, return_code, unsigned long, flags)
 493 {
 494         u64 sthyi_rc;
 495         void *info;
 496         int r;
 497
 498         if (flags)
 499                 return -EINVAL;
 500         if (function_code != STHYI_FC_CP_IFL_CAP)
 501                 return -EOPNOTSUPP;
 502         info = (void *)get_zeroed_page(GFP_KERNEL);
 503         if (!info)
 504                 return -ENOMEM;
 505         r = sthyi_fill(info, &sthyi_rc);
 506         if (r < 0)
 507                 goto out;
 508         if (return_code && put_user(sthyi_rc, return_code)) {
 509                 r = -EFAULT;
 510                 goto out;
 511         }
 512         if (copy_to_user(buffer, info, PAGE_SIZE))
 513                 r = -EFAULT;
 514 out:
 515         free_page((unsigned long)info);
 516         return r;
 517 }