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         if (stsi(sysinfo, 1, 1, 1))
 187                 return;
 188
 189         sclp_ocf_cpc_name_copy(sctns->mac.infmname);
 190
 191         memcpy(sctns->mac.infmtype, sysinfo->type, sizeof(sctns->mac.infmtype));
 192         memcpy(sctns->mac.infmmanu, sysinfo->manufacturer, sizeof(sctns->mac.infmmanu));
 193         memcpy(sctns->mac.infmpman, sysinfo->plant, sizeof(sctns->mac.infmpman));
 194         memcpy(sctns->mac.infmseq, sysinfo->sequence, sizeof(sctns->mac.infmseq));
 195
 196         sctns->mac.infmval1 |= MAC_ID_VLD | MAC_NAME_VLD;
 197 }
 198
 199 static void fill_stsi_par(struct sthyi_sctns *sctns,
 200                           struct sysinfo_2_2_2 *sysinfo)
 201 {
 202         if (stsi(sysinfo, 2, 2, 2))
 203                 return;
 204
 205         sctns->par.infppnum = sysinfo->lpar_number;
 206         memcpy(sctns->par.infppnam, sysinfo->name, sizeof(sctns->par.infppnam));
 207
 208         sctns->par.infpval1 |= PAR_ID_VLD;
 209 }
 210
 211 static void fill_stsi(struct sthyi_sctns *sctns)
 212 {
 213         void *sysinfo;
 214
 215         /* Errors are handled through the validity bits in the response. */
 216         sysinfo = (void *)__get_free_page(GFP_KERNEL);
 217         if (!sysinfo)
 218                 return;
 219
 220         fill_stsi_mac(sctns, sysinfo);
 221         fill_stsi_par(sctns, sysinfo);
 222
 223         free_pages((unsigned long)sysinfo, 0);
 224 }
 225
 226 static void fill_diag_mac(struct sthyi_sctns *sctns,
 227                           struct diag204_x_phys_block *block,
 228                           void *diag224_buf)
 229 {
 230         int i;
 231
 232         for (i = 0; i < block->hdr.cpus; i++) {
 233                 switch (cpu_id(block->cpus[i].ctidx, diag224_buf)) {
 234                 case CP:
 235                         if (block->cpus[i].weight == DED_WEIGHT)
 236                                 sctns->mac.infmdcps++;
 237                         else
 238                                 sctns->mac.infmscps++;
 239                         break;
 240                 case IFL:
 241                         if (block->cpus[i].weight == DED_WEIGHT)
 242                                 sctns->mac.infmdifl++;
 243                         else
 244                                 sctns->mac.infmsifl++;
 245                         break;
 246                 }
 247         }
 248         sctns->mac.infmval1 |= MAC_CNT_VLD;
 249 }
 250
 251 /* Returns a pointer to the the next partition block. */
 252 static struct diag204_x_part_block *lpar_cpu_inf(struct lpar_cpu_inf *part_inf,
 253                                                  bool this_lpar,
 254                                                  void *diag224_buf,
 255                                                  struct diag204_x_part_block *block)
 256 {
 257         int i, capped = 0, weight_cp = 0, weight_ifl = 0;
 258         struct cpu_inf *cpu_inf;
 259
 260         for (i = 0; i < block->hdr.rcpus; i++) {
 261                 if (!(block->cpus[i].cflag & DIAG204_CPU_ONLINE))
 262                         continue;
 263
 264                 switch (cpu_id(block->cpus[i].ctidx, diag224_buf)) {
 265                 case CP:
 266                         cpu_inf = &part_inf->cp;
 267                         if (block->cpus[i].cur_weight < DED_WEIGHT)
 268                                 weight_cp |= block->cpus[i].cur_weight;
 269                         break;
 270                 case IFL:
 271                         cpu_inf = &part_inf->ifl;
 272                         if (block->cpus[i].cur_weight < DED_WEIGHT)
 273                                 weight_ifl |= block->cpus[i].cur_weight;
 274                         break;
 275                 default:
 276                         continue;
 277                 }
 278
 279                 if (!this_lpar)
 280                         continue;
 281
 282                 capped |= block->cpus[i].cflag & DIAG204_CPU_CAPPED;
 283                 cpu_inf->lpar_cap |= block->cpus[i].cpu_type_cap;
 284                 cpu_inf->lpar_grp_cap |= block->cpus[i].group_cpu_type_cap;
 285
 286                 if (block->cpus[i].weight == DED_WEIGHT)
 287                         cpu_inf->cpu_num_ded += 1;
 288                 else
 289                         cpu_inf->cpu_num_shd += 1;
 290         }
 291
 292         if (this_lpar && capped) {
 293                 part_inf->cp.lpar_weight = weight_cp;
 294                 part_inf->ifl.lpar_weight = weight_ifl;
 295         }
 296         part_inf->cp.all_weight += weight_cp;
 297         part_inf->ifl.all_weight += weight_ifl;
 298         return (struct diag204_x_part_block *)&block->cpus[i];
 299 }
 300
 301 static void fill_diag(struct sthyi_sctns *sctns)
 302 {
 303         int i, r, pages;
 304         bool this_lpar;
 305         void *diag204_buf;
 306         void *diag224_buf = NULL;
 307         struct diag204_x_info_blk_hdr *ti_hdr;
 308         struct diag204_x_part_block *part_block;
 309         struct diag204_x_phys_block *phys_block;
 310         struct lpar_cpu_inf lpar_inf = {};
 311
 312         /* Errors are handled through the validity bits in the response. */
 313         pages = diag204((unsigned long)DIAG204_SUBC_RSI |
 314                         (unsigned long)DIAG204_INFO_EXT, 0, NULL);
 315         if (pages <= 0)
 316                 return;
 317
 318         diag204_buf = vmalloc(PAGE_SIZE * pages);
 319         if (!diag204_buf)
 320                 return;
 321
 322         r = diag204((unsigned long)DIAG204_SUBC_STIB7 |
 323                     (unsigned long)DIAG204_INFO_EXT, pages, diag204_buf);
 324         if (r < 0)
 325                 goto out;
 326
 327         diag224_buf = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
 328         if (!diag224_buf || diag224(diag224_buf))
 329                 goto out;
 330
 331         ti_hdr = diag204_buf;
 332         part_block = diag204_buf + sizeof(*ti_hdr);
 333
 334         for (i = 0; i < ti_hdr->npar; i++) {
 335                 /*
 336                  * For the calling lpar we also need to get the cpu
 337                  * caps and weights. The time information block header
 338                  * specifies the offset to the partition block of the
 339                  * caller lpar, so we know when we process its data.
 340                  */
 341                 this_lpar = (void *)part_block - diag204_buf == ti_hdr->this_part;
 342                 part_block = lpar_cpu_inf(&lpar_inf, this_lpar, diag224_buf,
 343                                           part_block);
 344         }
 345
 346         phys_block = (struct diag204_x_phys_block *)part_block;
 347         part_block = diag204_buf + ti_hdr->this_part;
 348         if (part_block->hdr.mtid)
 349                 sctns->par.infpflg1 = PAR_MT_EN;
 350
 351         sctns->par.infpval1 |= PAR_GRP_VLD;
 352         sctns->par.infplgcp = scale_cap(lpar_inf.cp.lpar_grp_cap);
 353         sctns->par.infplgif = scale_cap(lpar_inf.ifl.lpar_grp_cap);
 354         memcpy(sctns->par.infplgnm, part_block->hdr.hardware_group_name,
 355                sizeof(sctns->par.infplgnm));
 356
 357         sctns->par.infpscps = lpar_inf.cp.cpu_num_shd;
 358         sctns->par.infpdcps = lpar_inf.cp.cpu_num_ded;
 359         sctns->par.infpsifl = lpar_inf.ifl.cpu_num_shd;
 360         sctns->par.infpdifl = lpar_inf.ifl.cpu_num_ded;
 361         sctns->par.infpval1 |= PAR_PCNT_VLD;
 362
 363         sctns->par.infpabcp = scale_cap(lpar_inf.cp.lpar_cap);
 364         sctns->par.infpabif = scale_cap(lpar_inf.ifl.lpar_cap);
 365         sctns->par.infpval1 |= PAR_ABS_VLD;
 366
 367         /*
 368          * Everything below needs global performance data to be
 369          * meaningful.
 370          */
 371         if (!(ti_hdr->flags & DIAG204_LPAR_PHYS_FLG)) {
 372                 sctns->hdr.infhflg1 |= HDR_PERF_UNAV;
 373                 goto out;
 374         }
 375
 376         fill_diag_mac(sctns, phys_block, diag224_buf);
 377
 378         if (lpar_inf.cp.lpar_weight) {
 379                 sctns->par.infpwbcp = sctns->mac.infmscps * 0x10000 *
 380                         lpar_inf.cp.lpar_weight / lpar_inf.cp.all_weight;
 381         }
 382
 383         if (lpar_inf.ifl.lpar_weight) {
 384                 sctns->par.infpwbif = sctns->mac.infmsifl * 0x10000 *
 385                         lpar_inf.ifl.lpar_weight / lpar_inf.ifl.all_weight;
 386         }
 387         sctns->par.infpval1 |= PAR_WGHT_VLD;
 388
 389 out:
 390         free_page((unsigned long)diag224_buf);
 391         vfree(diag204_buf);
 392 }
 393
 394 static int sthyi(u64 vaddr, u64 *rc)
 395 {
 396         register u64 code asm("0") = 0;
 397         register u64 addr asm("2") = vaddr;
 398         register u64 rcode asm("3");
 399         int cc;
 400
 401         asm volatile(
 402                 ".insn   rre,0xB2560000,%[code],%[addr]\n"
 403                 "ipm     %[cc]\n"
 404                 "srl     %[cc],28\n"
 405                 : [cc] "=d" (cc), "=d" (rcode)
 406                 : [code] "d" (code), [addr] "a" (addr)
 407                 : "memory", "cc");
 408         *rc = rcode;
 409         return cc;
 410 }
 411
 412 static int fill_dst(void *dst, u64 *rc)
 413 {
 414         struct sthyi_sctns *sctns = (struct sthyi_sctns *)dst;
 415
 416         /*
 417          * If the facility is on, we don't want to emulate the instruction.
 418          * We ask the hypervisor to provide the data.
 419          */
 420         if (test_facility(74))
 421                 return sthyi((u64)dst, rc);
 422
 423         fill_hdr(sctns);
 424         fill_stsi(sctns);
 425         fill_diag(sctns);
 426         *rc = 0;
 427         return 0;
 428 }
 429
 430 static int sthyi_init_cache(void)
 431 {
 432         if (sthyi_cache.info)
 433                 return 0;
 434         sthyi_cache.info = (void *)get_zeroed_page(GFP_KERNEL);
 435         if (!sthyi_cache.info)
 436                 return -ENOMEM;
 437         sthyi_cache.end = jiffies - 1; /* expired */
 438         return 0;
 439 }
 440
 441 static int sthyi_update_cache(u64 *rc)
 442 {
 443         int r;
 444
 445         memset(sthyi_cache.info, 0, PAGE_SIZE);
 446         r = fill_dst(sthyi_cache.info, rc);
 447         if (r)
 448                 return r;
 449         sthyi_cache.end = jiffies + CACHE_VALID_JIFFIES;
 450         return r;
 451 }
 452
 453 /*
 454  * sthyi_fill - Fill page with data returned by the STHYI instruction
 455  *
 456  * @dst: Pointer to zeroed page
 457  * @rc:  Pointer for storing the return code of the instruction
 458  *
 459  * Fills the destination with system information returned by the STHYI
 460  * instruction. The data is generated by emulation or execution of STHYI,
 461  * if available. The return value is the condition code that would be
 462  * returned, the rc parameter is the return code which is passed in
 463  * register R2 + 1.
 464  */
 465 int sthyi_fill(void *dst, u64 *rc)
 466 {
 467         int r;
 468
 469         mutex_lock(&sthyi_mutex);
 470         r = sthyi_init_cache();
 471         if (r)
 472                 goto out;
 473
 474         if (time_is_before_jiffies(sthyi_cache.end)) {
 475                 /* cache expired */
 476                 r = sthyi_update_cache(rc);
 477                 if (r)
 478                         goto out;
 479         }
 480         *rc = 0;
 481         memcpy(dst, sthyi_cache.info, PAGE_SIZE);
 482 out:
 483         mutex_unlock(&sthyi_mutex);
 484         return r;
 485 }
 486 EXPORT_SYMBOL_GPL(sthyi_fill);
 487
 488 SYSCALL_DEFINE4(s390_sthyi, unsigned long, function_code, void __user *, buffer,
 489                 u64 __user *, return_code, unsigned long, flags)
 490 {
 491         u64 sthyi_rc;
 492         void *info;
 493         int r;
 494
 495         if (flags)
 496                 return -EINVAL;
 497         if (function_code != STHYI_FC_CP_IFL_CAP)
 498                 return -EOPNOTSUPP;
 499         info = (void *)get_zeroed_page(GFP_KERNEL);
 500         if (!info)
 501                 return -ENOMEM;
 502         r = sthyi_fill(info, &sthyi_rc);
 503         if (r < 0)
 504                 goto out;
 505         if (return_code && put_user(sthyi_rc, return_code)) {
 506                 r = -EFAULT;
 507                 goto out;
 508         }
 509         if (copy_to_user(buffer, info, PAGE_SIZE))
 510                 r = -EFAULT;
 511 out:
 512         free_page((unsigned long)info);
 513         return r;
 514 }