arch/s390/kvm/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 <[email protected]>
  10  */
  11 #include <linux/kvm_host.h>
  12 #include <linux/errno.h>
  13 #include <linux/pagemap.h>
  14 #include <linux/vmalloc.h>
  15 #include <linux/ratelimit.h>
  16
  17 #include <asm/kvm_host.h>
  18 #include <asm/asm-offsets.h>
  19 #include <asm/sclp.h>
  20 #include <asm/diag.h>
  21 #include <asm/sysinfo.h>
  22 #include <asm/ebcdic.h>
  23
  24 #include "kvm-s390.h"
  25 #include "gaccess.h"
  26 #include "trace.h"
  27
  28 #define DED_WEIGHT 0xffff
  29 /*
  30  * CP and IFL as EBCDIC strings, SP/0x40 determines the end of string
  31  * as they are justified with spaces.
  32  */
  33 #define CP  0xc3d7404040404040UL
  34 #define IFL 0xc9c6d34040404040UL
  35
  36 enum hdr_flags {
  37         HDR_NOT_LPAR   = 0x10,
  38         HDR_STACK_INCM = 0x20,
  39         HDR_STSI_UNAV  = 0x40,
  40         HDR_PERF_UNAV  = 0x80,
  41 };
  42
  43 enum mac_validity {
  44         MAC_NAME_VLD = 0x20,
  45         MAC_ID_VLD   = 0x40,
  46         MAC_CNT_VLD  = 0x80,
  47 };
  48
  49 enum par_flag {
  50         PAR_MT_EN = 0x80,
  51 };
  52
  53 enum par_validity {
  54         PAR_GRP_VLD  = 0x08,
  55         PAR_ID_VLD   = 0x10,
  56         PAR_ABS_VLD  = 0x20,
  57         PAR_WGHT_VLD = 0x40,
  58         PAR_PCNT_VLD  = 0x80,
  59 };
  60
  61 struct hdr_sctn {
  62         u8 infhflg1;
  63         u8 infhflg2; /* reserved */
  64         u8 infhval1; /* reserved */
  65         u8 infhval2; /* reserved */
  66         u8 reserved[3];
  67         u8 infhygct;
  68         u16 infhtotl;
  69         u16 infhdln;
  70         u16 infmoff;
  71         u16 infmlen;
  72         u16 infpoff;
  73         u16 infplen;
  74         u16 infhoff1;
  75         u16 infhlen1;
  76         u16 infgoff1;
  77         u16 infglen1;
  78         u16 infhoff2;
  79         u16 infhlen2;
  80         u16 infgoff2;
  81         u16 infglen2;
  82         u16 infhoff3;
  83         u16 infhlen3;
  84         u16 infgoff3;
  85         u16 infglen3;
  86         u8 reserved2[4];
  87 } __packed;
  88
  89 struct mac_sctn {
  90         u8 infmflg1; /* reserved */
  91         u8 infmflg2; /* reserved */
  92         u8 infmval1;
  93         u8 infmval2; /* reserved */
  94         u16 infmscps;
  95         u16 infmdcps;
  96         u16 infmsifl;
  97         u16 infmdifl;
  98         char infmname[8];
  99         char infmtype[4];
 100         char infmmanu[16];
 101         char infmseq[16];
 102         char infmpman[4];
 103         u8 reserved[4];
 104 } __packed;
 105
 106 struct par_sctn {
 107         u8 infpflg1;
 108         u8 infpflg2; /* reserved */
 109         u8 infpval1;
 110         u8 infpval2; /* reserved */
 111         u16 infppnum;
 112         u16 infpscps;
 113         u16 infpdcps;
 114         u16 infpsifl;
 115         u16 infpdifl;
 116         u16 reserved;
 117         char infppnam[8];
 118         u32 infpwbcp;
 119         u32 infpabcp;
 120         u32 infpwbif;
 121         u32 infpabif;
 122         char infplgnm[8];
 123         u32 infplgcp;
 124         u32 infplgif;
 125 } __packed;
 126
 127 struct sthyi_sctns {
 128         struct hdr_sctn hdr;
 129         struct mac_sctn mac;
 130         struct par_sctn par;
 131 } __packed;
 132
 133 struct cpu_inf {
 134         u64 lpar_cap;
 135         u64 lpar_grp_cap;
 136         u64 lpar_weight;
 137         u64 all_weight;
 138         int cpu_num_ded;
 139         int cpu_num_shd;
 140 };
 141
 142 struct lpar_cpu_inf {
 143         struct cpu_inf cp;
 144         struct cpu_inf ifl;
 145 };
 146
 147 static inline u64 cpu_id(u8 ctidx, void *diag224_buf)
 148 {
 149         return *((u64 *)(diag224_buf + (ctidx + 1) * DIAG204_CPU_NAME_LEN));
 150 }
 151
 152 /*
 153  * Scales the cpu capping from the lpar range to the one expected in
 154  * sthyi data.
 155  *
 156  * diag204 reports a cap in hundredths of processor units.
 157  * z/VM's range for one core is 0 - 0x10000.
 158  */
 159 static u32 scale_cap(u32 in)
 160 {
 161         return (0x10000 * in) / 100;
 162 }
 163
 164 static void fill_hdr(struct sthyi_sctns *sctns)
 165 {
 166         sctns->hdr.infhdln = sizeof(sctns->hdr);
 167         sctns->hdr.infmoff = sizeof(sctns->hdr);
 168         sctns->hdr.infmlen = sizeof(sctns->mac);
 169         sctns->hdr.infplen = sizeof(sctns->par);
 170         sctns->hdr.infpoff = sctns->hdr.infhdln + sctns->hdr.infmlen;
 171         sctns->hdr.infhtotl = sctns->hdr.infpoff + sctns->hdr.infplen;
 172 }
 173
 174 static void fill_stsi_mac(struct sthyi_sctns *sctns,
 175                           struct sysinfo_1_1_1 *sysinfo)
 176 {
 177         if (stsi(sysinfo, 1, 1, 1))
 178                 return;
 179
 180         sclp_ocf_cpc_name_copy(sctns->mac.infmname);
 181
 182         memcpy(sctns->mac.infmtype, sysinfo->type, sizeof(sctns->mac.infmtype));
 183         memcpy(sctns->mac.infmmanu, sysinfo->manufacturer, sizeof(sctns->mac.infmmanu));
 184         memcpy(sctns->mac.infmpman, sysinfo->plant, sizeof(sctns->mac.infmpman));
 185         memcpy(sctns->mac.infmseq, sysinfo->sequence, sizeof(sctns->mac.infmseq));
 186
 187         sctns->mac.infmval1 |= MAC_ID_VLD | MAC_NAME_VLD;
 188 }
 189
 190 static void fill_stsi_par(struct sthyi_sctns *sctns,
 191                           struct sysinfo_2_2_2 *sysinfo)
 192 {
 193         if (stsi(sysinfo, 2, 2, 2))
 194                 return;
 195
 196         sctns->par.infppnum = sysinfo->lpar_number;
 197         memcpy(sctns->par.infppnam, sysinfo->name, sizeof(sctns->par.infppnam));
 198
 199         sctns->par.infpval1 |= PAR_ID_VLD;
 200 }
 201
 202 static void fill_stsi(struct sthyi_sctns *sctns)
 203 {
 204         void *sysinfo;
 205
 206         /* Errors are handled through the validity bits in the response. */
 207         sysinfo = (void *)__get_free_page(GFP_KERNEL);
 208         if (!sysinfo)
 209                 return;
 210
 211         fill_stsi_mac(sctns, sysinfo);
 212         fill_stsi_par(sctns, sysinfo);
 213
 214         free_pages((unsigned long)sysinfo, 0);
 215 }
 216
 217 static void fill_diag_mac(struct sthyi_sctns *sctns,
 218                           struct diag204_x_phys_block *block,
 219                           void *diag224_buf)
 220 {
 221         int i;
 222
 223         for (i = 0; i < block->hdr.cpus; i++) {
 224                 switch (cpu_id(block->cpus[i].ctidx, diag224_buf)) {
 225                 case CP:
 226                         if (block->cpus[i].weight == DED_WEIGHT)
 227                                 sctns->mac.infmdcps++;
 228                         else
 229                                 sctns->mac.infmscps++;
 230                         break;
 231                 case IFL:
 232                         if (block->cpus[i].weight == DED_WEIGHT)
 233                                 sctns->mac.infmdifl++;
 234                         else
 235                                 sctns->mac.infmsifl++;
 236                         break;
 237                 }
 238         }
 239         sctns->mac.infmval1 |= MAC_CNT_VLD;
 240 }
 241
 242 /* Returns a pointer to the the next partition block. */
 243 static struct diag204_x_part_block *lpar_cpu_inf(struct lpar_cpu_inf *part_inf,
 244                                                  bool this_lpar,
 245                                                  void *diag224_buf,
 246                                                  struct diag204_x_part_block *block)
 247 {
 248         int i, capped = 0, weight_cp = 0, weight_ifl = 0;
 249         struct cpu_inf *cpu_inf;
 250
 251         for (i = 0; i < block->hdr.rcpus; i++) {
 252                 if (!(block->cpus[i].cflag & DIAG204_CPU_ONLINE))
 253                         continue;
 254
 255                 switch (cpu_id(block->cpus[i].ctidx, diag224_buf)) {
 256                 case CP:
 257                         cpu_inf = &part_inf->cp;
 258                         if (block->cpus[i].cur_weight < DED_WEIGHT)
 259                                 weight_cp |= block->cpus[i].cur_weight;
 260                         break;
 261                 case IFL:
 262                         cpu_inf = &part_inf->ifl;
 263                         if (block->cpus[i].cur_weight < DED_WEIGHT)
 264                                 weight_ifl |= block->cpus[i].cur_weight;
 265                         break;
 266                 default:
 267                         continue;
 268                 }
 269
 270                 if (!this_lpar)
 271                         continue;
 272
 273                 capped |= block->cpus[i].cflag & DIAG204_CPU_CAPPED;
 274                 cpu_inf->lpar_cap |= block->cpus[i].cpu_type_cap;
 275                 cpu_inf->lpar_grp_cap |= block->cpus[i].group_cpu_type_cap;
 276
 277                 if (block->cpus[i].weight == DED_WEIGHT)
 278                         cpu_inf->cpu_num_ded += 1;
 279                 else
 280                         cpu_inf->cpu_num_shd += 1;
 281         }
 282
 283         if (this_lpar && capped) {
 284                 part_inf->cp.lpar_weight = weight_cp;
 285                 part_inf->ifl.lpar_weight = weight_ifl;
 286         }
 287         part_inf->cp.all_weight += weight_cp;
 288         part_inf->ifl.all_weight += weight_ifl;
 289         return (struct diag204_x_part_block *)&block->cpus[i];
 290 }
 291
 292 static void fill_diag(struct sthyi_sctns *sctns)
 293 {
 294         int i, r, pages;
 295         bool this_lpar;
 296         void *diag204_buf;
 297         void *diag224_buf = NULL;
 298         struct diag204_x_info_blk_hdr *ti_hdr;
 299         struct diag204_x_part_block *part_block;
 300         struct diag204_x_phys_block *phys_block;
 301         struct lpar_cpu_inf lpar_inf = {};
 302
 303         /* Errors are handled through the validity bits in the response. */
 304         pages = diag204((unsigned long)DIAG204_SUBC_RSI |
 305                         (unsigned long)DIAG204_INFO_EXT, 0, NULL);
 306         if (pages <= 0)
 307                 return;
 308
 309         diag204_buf = vmalloc(PAGE_SIZE * pages);
 310         if (!diag204_buf)
 311                 return;
 312
 313         r = diag204((unsigned long)DIAG204_SUBC_STIB7 |
 314                     (unsigned long)DIAG204_INFO_EXT, pages, diag204_buf);
 315         if (r < 0)
 316                 goto out;
 317
 318         diag224_buf = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
 319         if (!diag224_buf || diag224(diag224_buf))
 320                 goto out;
 321
 322         ti_hdr = diag204_buf;
 323         part_block = diag204_buf + sizeof(*ti_hdr);
 324
 325         for (i = 0; i < ti_hdr->npar; i++) {
 326                 /*
 327                  * For the calling lpar we also need to get the cpu
 328                  * caps and weights. The time information block header
 329                  * specifies the offset to the partition block of the
 330                  * caller lpar, so we know when we process its data.
 331                  */
 332                 this_lpar = (void *)part_block - diag204_buf == ti_hdr->this_part;
 333                 part_block = lpar_cpu_inf(&lpar_inf, this_lpar, diag224_buf,
 334                                           part_block);
 335         }
 336
 337         phys_block = (struct diag204_x_phys_block *)part_block;
 338         part_block = diag204_buf + ti_hdr->this_part;
 339         if (part_block->hdr.mtid)
 340                 sctns->par.infpflg1 = PAR_MT_EN;
 341
 342         sctns->par.infpval1 |= PAR_GRP_VLD;
 343         sctns->par.infplgcp = scale_cap(lpar_inf.cp.lpar_grp_cap);
 344         sctns->par.infplgif = scale_cap(lpar_inf.ifl.lpar_grp_cap);
 345         memcpy(sctns->par.infplgnm, part_block->hdr.hardware_group_name,
 346                sizeof(sctns->par.infplgnm));
 347
 348         sctns->par.infpscps = lpar_inf.cp.cpu_num_shd;
 349         sctns->par.infpdcps = lpar_inf.cp.cpu_num_ded;
 350         sctns->par.infpsifl = lpar_inf.ifl.cpu_num_shd;
 351         sctns->par.infpdifl = lpar_inf.ifl.cpu_num_ded;
 352         sctns->par.infpval1 |= PAR_PCNT_VLD;
 353
 354         sctns->par.infpabcp = scale_cap(lpar_inf.cp.lpar_cap);
 355         sctns->par.infpabif = scale_cap(lpar_inf.ifl.lpar_cap);
 356         sctns->par.infpval1 |= PAR_ABS_VLD;
 357
 358         /*
 359          * Everything below needs global performance data to be
 360          * meaningful.
 361          */
 362         if (!(ti_hdr->flags & DIAG204_LPAR_PHYS_FLG)) {
 363                 sctns->hdr.infhflg1 |= HDR_PERF_UNAV;
 364                 goto out;
 365         }
 366
 367         fill_diag_mac(sctns, phys_block, diag224_buf);
 368
 369         if (lpar_inf.cp.lpar_weight) {
 370                 sctns->par.infpwbcp = sctns->mac.infmscps * 0x10000 *
 371                         lpar_inf.cp.lpar_weight / lpar_inf.cp.all_weight;
 372         }
 373
 374         if (lpar_inf.ifl.lpar_weight) {
 375                 sctns->par.infpwbif = sctns->mac.infmsifl * 0x10000 *
 376                         lpar_inf.ifl.lpar_weight / lpar_inf.ifl.all_weight;
 377         }
 378         sctns->par.infpval1 |= PAR_WGHT_VLD;
 379
 380 out:
 381         free_page((unsigned long)diag224_buf);
 382         vfree(diag204_buf);
 383 }
 384
 385 static int sthyi(u64 vaddr)
 386 {
 387         register u64 code asm("0") = 0;
 388         register u64 addr asm("2") = vaddr;
 389         int cc;
 390
 391         asm volatile(
 392                 ".insn   rre,0xB2560000,%[code],%[addr]\n"
 393                 "ipm     %[cc]\n"
 394                 "srl     %[cc],28\n"
 395                 : [cc] "=d" (cc)
 396                 : [code] "d" (code), [addr] "a" (addr)
 397                 : "3", "memory", "cc");
 398         return cc;
 399 }
 400
 401 int handle_sthyi(struct kvm_vcpu *vcpu)
 402 {
 403         int reg1, reg2, r = 0;
 404         u64 code, addr, cc = 0;
 405         struct sthyi_sctns *sctns = NULL;
 406
 407         if (!test_kvm_facility(vcpu->kvm, 74))
 408                 return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
 409
 410         /*
 411          * STHYI requires extensive locking in the higher hypervisors
 412          * and is very computational/memory expensive. Therefore we
 413          * ratelimit the executions per VM.
 414          */
 415         if (!__ratelimit(&vcpu->kvm->arch.sthyi_limit)) {
 416                 kvm_s390_retry_instr(vcpu);
 417                 return 0;
 418         }
 419
 420         kvm_s390_get_regs_rre(vcpu, &reg1, &reg2);
 421         code = vcpu->run->s.regs.gprs[reg1];
 422         addr = vcpu->run->s.regs.gprs[reg2];
 423
 424         vcpu->stat.instruction_sthyi++;
 425         VCPU_EVENT(vcpu, 3, "STHYI: fc: %llu addr: 0x%016llx", code, addr);
 426         trace_kvm_s390_handle_sthyi(vcpu, code, addr);
 427
 428         if (reg1 == reg2 || reg1 & 1 || reg2 & 1)
 429                 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
 430
 431         if (code & 0xffff) {
 432                 cc = 3;
 433                 goto out;
 434         }
 435
 436         if (addr & ~PAGE_MASK)
 437                 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
 438
 439         /*
 440          * If the page has not yet been faulted in, we want to do that
 441          * now and not after all the expensive calculations.
 442          */
 443         r = write_guest(vcpu, addr, reg2, &cc, 1);
 444         if (r)
 445                 return kvm_s390_inject_prog_cond(vcpu, r);
 446
 447         sctns = (void *)get_zeroed_page(GFP_KERNEL);
 448         if (!sctns)
 449                 return -ENOMEM;
 450
 451         /*
 452          * If we are a guest, we don't want to emulate an emulated
 453          * instruction. We ask the hypervisor to provide the data.
 454          */
 455         if (test_facility(74)) {
 456                 cc = sthyi((u64)sctns);
 457                 goto out;
 458         }
 459
 460         fill_hdr(sctns);
 461         fill_stsi(sctns);
 462         fill_diag(sctns);
 463
 464 out:
 465         if (!cc) {
 466                 r = write_guest(vcpu, addr, reg2, sctns, PAGE_SIZE);
 467                 if (r) {
 468                         free_page((unsigned long)sctns);
 469                         return kvm_s390_inject_prog_cond(vcpu, r);
 470                 }
 471         }
 472
 473         free_page((unsigned long)sctns);
 474         vcpu->run->s.regs.gprs[reg2 + 1] = cc ? 4 : 0;
 475         kvm_s390_set_psw_cc(vcpu, cc);
 476         return r;
 477 }