arch/s390/kernel/sthyi.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * store hypervisor information instruction emulation functions.
   4  *
   5  * Copyright IBM Corp. 2016
   6  * Author(s): Janosch Frank <frankja@linux.vnet.ibm.com>
   7  */
   8 #include <linux/errno.h>
   9 #include <linux/pagemap.h>
  10 #include <linux/vmalloc.h>
  11 #include <linux/syscalls.h>
  12 #include <linux/mutex.h>
  13 #include <asm/asm-offsets.h>
  14 #include <asm/sclp.h>
  15 #include <asm/diag.h>
  16 #include <asm/sysinfo.h>
  17 #include <asm/ebcdic.h>
  18 #include <asm/facility.h>
  19 #include <asm/sthyi.h>
  20 #include "entry.h"
  21
  22 #define DED_WEIGHT 0xffff
  23 /*
  24  * CP and IFL as EBCDIC strings, SP/0x40 determines the end of string
  25  * as they are justified with spaces.
  26  */
  27 #define CP  0xc3d7404040404040UL
  28 #define IFL 0xc9c6d34040404040UL
  29
  30 enum hdr_flags {
  31         HDR_NOT_LPAR   = 0x10,
  32         HDR_STACK_INCM = 0x20,
  33         HDR_STSI_UNAV  = 0x40,
  34         HDR_PERF_UNAV  = 0x80,
  35 };
  36
  37 enum mac_validity {
  38         MAC_NAME_VLD = 0x20,
  39         MAC_ID_VLD   = 0x40,
  40         MAC_CNT_VLD  = 0x80,
  41 };
  42
  43 enum par_flag {
  44         PAR_MT_EN = 0x80,
  45 };
  46
  47 enum par_validity {
  48         PAR_GRP_VLD  = 0x08,
  49         PAR_ID_VLD   = 0x10,
  50         PAR_ABS_VLD  = 0x20,
  51         PAR_WGHT_VLD = 0x40,
  52         PAR_PCNT_VLD  = 0x80,
  53 };
  54
  55 struct hdr_sctn {
  56         u8 infhflg1;
  57         u8 infhflg2; /* reserved */
  58         u8 infhval1; /* reserved */
  59         u8 infhval2; /* reserved */
  60         u8 reserved[3];
  61         u8 infhygct;
  62         u16 infhtotl;
  63         u16 infhdln;
  64         u16 infmoff;
  65         u16 infmlen;
  66         u16 infpoff;
  67         u16 infplen;
  68         u16 infhoff1;
  69         u16 infhlen1;
  70         u16 infgoff1;
  71         u16 infglen1;
  72         u16 infhoff2;
  73         u16 infhlen2;
  74         u16 infgoff2;
  75         u16 infglen2;
  76         u16 infhoff3;
  77         u16 infhlen3;
  78         u16 infgoff3;
  79         u16 infglen3;
  80         u8 reserved2[4];
  81 } __packed;
  82
  83 struct mac_sctn {
  84         u8 infmflg1; /* reserved */
  85         u8 infmflg2; /* reserved */
  86         u8 infmval1;
  87         u8 infmval2; /* reserved */
  88         u16 infmscps;
  89         u16 infmdcps;
  90         u16 infmsifl;
  91         u16 infmdifl;
  92         char infmname[8];
  93         char infmtype[4];
  94         char infmmanu[16];
  95         char infmseq[16];
  96         char infmpman[4];
  97         u8 reserved[4];
  98 } __packed;
  99
 100 struct par_sctn {
 101         u8 infpflg1;
 102         u8 infpflg2; /* reserved */
 103         u8 infpval1;
 104         u8 infpval2; /* reserved */
 105         u16 infppnum;
 106         u16 infpscps;
 107         u16 infpdcps;
 108         u16 infpsifl;
 109         u16 infpdifl;
 110         u16 reserved;
 111         char infppnam[8];
 112         u32 infpwbcp;
 113         u32 infpabcp;
 114         u32 infpwbif;
 115         u32 infpabif;
 116         char infplgnm[8];
 117         u32 infplgcp;
 118         u32 infplgif;
 119 } __packed;
 120
 121 struct sthyi_sctns {
 122         struct hdr_sctn hdr;
 123         struct mac_sctn mac;
 124         struct par_sctn par;
 125 } __packed;
 126
 127 struct cpu_inf {
 128         u64 lpar_cap;
 129         u64 lpar_grp_cap;
 130         u64 lpar_weight;
 131         u64 all_weight;
 132         int cpu_num_ded;
 133         int cpu_num_shd;
 134 };
 135
 136 struct lpar_cpu_inf {
 137         struct cpu_inf cp;
 138         struct cpu_inf ifl;
 139 };
 140
 141 /*
 142  * STHYI requires extensive locking in the higher hypervisors
 143  * and is very computational/memory expensive. Therefore we
 144  * cache the retrieved data whose valid period is 1s.
 145  */
 146 #define CACHE_VALID_JIFFIES     HZ
 147
 148 struct sthyi_info {
 149         void *info;
 150         unsigned long end;
 151 };
 152
 153 static DEFINE_MUTEX(sthyi_mutex);
 154 static struct sthyi_info sthyi_cache;
 155
 156 static inline u64 cpu_id(u8 ctidx, void *diag224_buf)
 157 {
 158         return *((u64 *)(diag224_buf + (ctidx + 1) * DIAG204_CPU_NAME_LEN));
 159 }
 160
 161 /*
 162  * Scales the cpu capping from the lpar range to the one expected in
 163  * sthyi data.
 164  *
 165  * diag204 reports a cap in hundredths of processor units.
 166  * z/VM's range for one core is 0 - 0x10000.
 167  */
 168 static u32 scale_cap(u32 in)
 169 {
 170         return (0x10000 * in) / 100;
 171 }
 172
 173 static void fill_hdr(struct sthyi_sctns *sctns)
 174 {
 175         sctns->hdr.infhdln = sizeof(sctns->hdr);
 176         sctns->hdr.infmoff = sizeof(sctns->hdr);
 177         sctns->hdr.infmlen = sizeof(sctns->mac);
 178         sctns->hdr.infplen = sizeof(sctns->par);
 179         sctns->hdr.infpoff = sctns->hdr.infhdln + sctns->hdr.infmlen;
 180         sctns->hdr.infhtotl = sctns->hdr.infpoff + sctns->hdr.infplen;
 181 }
 182
 183 static void fill_stsi_mac(struct sthyi_sctns *sctns,
 184                           struct sysinfo_1_1_1 *sysinfo)
 185 {
 186         sclp_ocf_cpc_name_copy(sctns->mac.infmname);
 187         if (*(u64 *)sctns->mac.infmname != 0)
 188                 sctns->mac.infmval1 |= MAC_NAME_VLD;
 189
 190         if (stsi(sysinfo, 1, 1, 1))
 191                 return;
 192
 193         memcpy(sctns->mac.infmtype, sysinfo->type, sizeof(sctns->mac.infmtype));
 194         memcpy(sctns->mac.infmmanu, sysinfo->manufacturer, sizeof(sctns->mac.infmmanu));
 195         memcpy(sctns->mac.infmpman, sysinfo->plant, sizeof(sctns->mac.infmpman));
 196         memcpy(sctns->mac.infmseq, sysinfo->sequence, sizeof(sctns->mac.infmseq));
 197
 198         sctns->mac.infmval1 |= MAC_ID_VLD;
 199 }
 200
 201 static void fill_stsi_par(struct sthyi_sctns *sctns,
 202                           struct sysinfo_2_2_2 *sysinfo)
 203 {
 204         if (stsi(sysinfo, 2, 2, 2))
 205                 return;
 206
 207         sctns->par.infppnum = sysinfo->lpar_number;
 208         memcpy(sctns->par.infppnam, sysinfo->name, sizeof(sctns->par.infppnam));
 209
 210         sctns->par.infpval1 |= PAR_ID_VLD;
 211 }
 212
 213 static void fill_stsi(struct sthyi_sctns *sctns)
 214 {
 215         void *sysinfo;
 216
 217         /* Errors are handled through the validity bits in the response. */
 218         sysinfo = (void *)__get_free_page(GFP_KERNEL);
 219         if (!sysinfo)
 220                 return;
 221
 222         fill_stsi_mac(sctns, sysinfo);
 223         fill_stsi_par(sctns, sysinfo);
 224
 225         free_pages((unsigned long)sysinfo, 0);
 226 }
 227
 228 static void fill_diag_mac(struct sthyi_sctns *sctns,
 229                           struct diag204_x_phys_block *block,
 230                           void *diag224_buf)
 231 {
 232         int i;
 233
 234         for (i = 0; i < block->hdr.cpus; i++) {
 235                 switch (cpu_id(block->cpus[i].ctidx, diag224_buf)) {
 236                 case CP:
 237                         if (block->cpus[i].weight == DED_WEIGHT)
 238                                 sctns->mac.infmdcps++;
 239                         else
 240                                 sctns->mac.infmscps++;
 241                         break;
 242                 case IFL:
 243                         if (block->cpus[i].weight == DED_WEIGHT)
 244                                 sctns->mac.infmdifl++;
 245                         else
 246                                 sctns->mac.infmsifl++;
 247                         break;
 248                 }
 249         }
 250         sctns->mac.infmval1 |= MAC_CNT_VLD;
 251 }
 252
 253 /* Returns a pointer to the the next partition block. */
 254 static struct diag204_x_part_block *lpar_cpu_inf(struct lpar_cpu_inf *part_inf,
 255                                                  bool this_lpar,
 256                                                  void *diag224_buf,
 257                                                  struct diag204_x_part_block *block)
 258 {
 259         int i, capped = 0, weight_cp = 0, weight_ifl = 0;
 260         struct cpu_inf *cpu_inf;
 261
 262         for (i = 0; i < block->hdr.rcpus; i++) {
 263                 if (!(block->cpus[i].cflag & DIAG204_CPU_ONLINE))
 264                         continue;
 265
 266                 switch (cpu_id(block->cpus[i].ctidx, diag224_buf)) {
 267                 case CP:
 268                         cpu_inf = &part_inf->cp;
 269                         if (block->cpus[i].cur_weight < DED_WEIGHT)
 270                                 weight_cp |= block->cpus[i].cur_weight;
 271                         break;
 272                 case IFL:
 273                         cpu_inf = &part_inf->ifl;
 274                         if (block->cpus[i].cur_weight < DED_WEIGHT)
 275                                 weight_ifl |= block->cpus[i].cur_weight;
 276                         break;
 277                 default:
 278                         continue;
 279                 }
 280
 281                 if (!this_lpar)
 282                         continue;
 283
 284                 capped |= block->cpus[i].cflag & DIAG204_CPU_CAPPED;
 285                 cpu_inf->lpar_cap |= block->cpus[i].cpu_type_cap;
 286                 cpu_inf->lpar_grp_cap |= block->cpus[i].group_cpu_type_cap;
 287
 288                 if (block->cpus[i].weight == DED_WEIGHT)
 289                         cpu_inf->cpu_num_ded += 1;
 290                 else
 291                         cpu_inf->cpu_num_shd += 1;
 292         }
 293
 294         if (this_lpar && capped) {
 295                 part_inf->cp.lpar_weight = weight_cp;
 296                 part_inf->ifl.lpar_weight = weight_ifl;
 297         }
 298         part_inf->cp.all_weight += weight_cp;
 299         part_inf->ifl.all_weight += weight_ifl;
 300         return (struct diag204_x_part_block *)&block->cpus[i];
 301 }
 302
 303 static void fill_diag(struct sthyi_sctns *sctns)
 304 {
 305         int i, r, pages;
 306         bool this_lpar;
 307         void *diag204_buf;
 308         void *diag224_buf = NULL;
 309         struct diag204_x_info_blk_hdr *ti_hdr;
 310         struct diag204_x_part_block *part_block;
 311         struct diag204_x_phys_block *phys_block;
 312         struct lpar_cpu_inf lpar_inf = {};
 313
 314         /* Errors are handled through the validity bits in the response. */
 315         pages = diag204((unsigned long)DIAG204_SUBC_RSI |
 316                         (unsigned long)DIAG204_INFO_EXT, 0, NULL);
 317         if (pages <= 0)
 318                 return;
 319
 320         diag204_buf = vmalloc(array_size(pages, PAGE_SIZE));
 321         if (!diag204_buf)
 322                 return;
 323
 324         r = diag204((unsigned long)DIAG204_SUBC_STIB7 |
 325                     (unsigned long)DIAG204_INFO_EXT, pages, diag204_buf);
 326         if (r < 0)
 327                 goto out;
 328
 329         diag224_buf = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
 330         if (!diag224_buf || diag224(diag224_buf))
 331                 goto out;
 332
 333         ti_hdr = diag204_buf;
 334         part_block = diag204_buf + sizeof(*ti_hdr);
 335
 336         for (i = 0; i < ti_hdr->npar; i++) {
 337                 /*
 338                  * For the calling lpar we also need to get the cpu
 339                  * caps and weights. The time information block header
 340                  * specifies the offset to the partition block of the
 341                  * caller lpar, so we know when we process its data.
 342                  */
 343                 this_lpar = (void *)part_block - diag204_buf == ti_hdr->this_part;
 344                 part_block = lpar_cpu_inf(&lpar_inf, this_lpar, diag224_buf,
 345                                           part_block);
 346         }
 347
 348         phys_block = (struct diag204_x_phys_block *)part_block;
 349         part_block = diag204_buf + ti_hdr->this_part;
 350         if (part_block->hdr.mtid)
 351                 sctns->par.infpflg1 = PAR_MT_EN;
 352
 353         sctns->par.infpval1 |= PAR_GRP_VLD;
 354         sctns->par.infplgcp = scale_cap(lpar_inf.cp.lpar_grp_cap);
 355         sctns->par.infplgif = scale_cap(lpar_inf.ifl.lpar_grp_cap);
 356         memcpy(sctns->par.infplgnm, part_block->hdr.hardware_group_name,
 357                sizeof(sctns->par.infplgnm));
 358
 359         sctns->par.infpscps = lpar_inf.cp.cpu_num_shd;
 360         sctns->par.infpdcps = lpar_inf.cp.cpu_num_ded;
 361         sctns->par.infpsifl = lpar_inf.ifl.cpu_num_shd;
 362         sctns->par.infpdifl = lpar_inf.ifl.cpu_num_ded;
 363         sctns->par.infpval1 |= PAR_PCNT_VLD;
 364
 365         sctns->par.infpabcp = scale_cap(lpar_inf.cp.lpar_cap);
 366         sctns->par.infpabif = scale_cap(lpar_inf.ifl.lpar_cap);
 367         sctns->par.infpval1 |= PAR_ABS_VLD;
 368
 369         /*
 370          * Everything below needs global performance data to be
 371          * meaningful.
 372          */
 373         if (!(ti_hdr->flags & DIAG204_LPAR_PHYS_FLG)) {
 374                 sctns->hdr.infhflg1 |= HDR_PERF_UNAV;
 375                 goto out;
 376         }
 377
 378         fill_diag_mac(sctns, phys_block, diag224_buf);
 379
 380         if (lpar_inf.cp.lpar_weight) {
 381                 sctns->par.infpwbcp = sctns->mac.infmscps * 0x10000 *
 382                         lpar_inf.cp.lpar_weight / lpar_inf.cp.all_weight;
 383         }
 384
 385         if (lpar_inf.ifl.lpar_weight) {
 386                 sctns->par.infpwbif = sctns->mac.infmsifl * 0x10000 *
 387                         lpar_inf.ifl.lpar_weight / lpar_inf.ifl.all_weight;
 388         }
 389         sctns->par.infpval1 |= PAR_WGHT_VLD;
 390
 391 out:
 392         free_page((unsigned long)diag224_buf);
 393         vfree(diag204_buf);
 394 }
 395
 396 static int sthyi(u64 vaddr, u64 *rc)
 397 {
 398         register u64 code asm("0") = 0;
 399         register u64 addr asm("2") = vaddr;
 400         register u64 rcode asm("3");
 401         int cc;
 402
 403         asm volatile(
 404                 ".insn   rre,0xB2560000,%[code],%[addr]\n"
 405                 "ipm     %[cc]\n"
 406                 "srl     %[cc],28\n"
 407                 : [cc] "=d" (cc), "=d" (rcode)
 408                 : [code] "d" (code), [addr] "a" (addr)
 409                 : "memory", "cc");
 410         *rc = rcode;
 411         return cc;
 412 }
 413
 414 static int fill_dst(void *dst, u64 *rc)
 415 {
 416         struct sthyi_sctns *sctns = (struct sthyi_sctns *)dst;
 417
 418         /*
 419          * If the facility is on, we don't want to emulate the instruction.
 420          * We ask the hypervisor to provide the data.
 421          */
 422         if (test_facility(74))
 423                 return sthyi((u64)dst, rc);
 424
 425         fill_hdr(sctns);
 426         fill_stsi(sctns);
 427         fill_diag(sctns);
 428         *rc = 0;
 429         return 0;
 430 }
 431
 432 static int sthyi_init_cache(void)
 433 {
 434         if (sthyi_cache.info)
 435                 return 0;
 436         sthyi_cache.info = (void *)get_zeroed_page(GFP_KERNEL);
 437         if (!sthyi_cache.info)
 438                 return -ENOMEM;
 439         sthyi_cache.end = jiffies - 1; /* expired */
 440         return 0;
 441 }
 442
 443 static int sthyi_update_cache(u64 *rc)
 444 {
 445         int r;
 446
 447         memset(sthyi_cache.info, 0, PAGE_SIZE);
 448         r = fill_dst(sthyi_cache.info, rc);
 449         if (r)
 450                 return r;
 451         sthyi_cache.end = jiffies + CACHE_VALID_JIFFIES;
 452         return r;
 453 }
 454
 455 /*
 456  * sthyi_fill - Fill page with data returned by the STHYI instruction
 457  *
 458  * @dst: Pointer to zeroed page
 459  * @rc:  Pointer for storing the return code of the instruction
 460  *
 461  * Fills the destination with system information returned by the STHYI
 462  * instruction. The data is generated by emulation or execution of STHYI,
 463  * if available. The return value is the condition code that would be
 464  * returned, the rc parameter is the return code which is passed in
 465  * register R2 + 1.
 466  */
 467 int sthyi_fill(void *dst, u64 *rc)
 468 {
 469         int r;
 470
 471         mutex_lock(&sthyi_mutex);
 472         r = sthyi_init_cache();
 473         if (r)
 474                 goto out;
 475
 476         if (time_is_before_jiffies(sthyi_cache.end)) {
 477                 /* cache expired */
 478                 r = sthyi_update_cache(rc);
 479                 if (r)
 480                         goto out;
 481         }
 482         *rc = 0;
 483         memcpy(dst, sthyi_cache.info, PAGE_SIZE);
 484 out:
 485         mutex_unlock(&sthyi_mutex);
 486         return r;
 487 }
 488 EXPORT_SYMBOL_GPL(sthyi_fill);
 489
 490 SYSCALL_DEFINE4(s390_sthyi, unsigned long, function_code, void __user *, buffer,
 491                 u64 __user *, return_code, unsigned long, flags)
 492 {
 493         u64 sthyi_rc;
 494         void *info;
 495         int r;
 496
 497         if (flags)
 498                 return -EINVAL;
 499         if (function_code != STHYI_FC_CP_IFL_CAP)
 500                 return -EOPNOTSUPP;
 501         info = (void *)get_zeroed_page(GFP_KERNEL);
 502         if (!info)
 503                 return -ENOMEM;
 504         r = sthyi_fill(info, &sthyi_rc);
 505         if (r < 0)
 506                 goto out;
 507         if (return_code && put_user(sthyi_rc, return_code)) {
 508                 r = -EFAULT;
 509                 goto out;
 510         }
 511         if (copy_to_user(buffer, info, PAGE_SIZE))
 512                 r = -EFAULT;
 513 out:
 514         free_page((unsigned long)info);
 515         return r;
 516 }