arch/s390/kernel/setup.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  S390 version
   4  *    Copyright IBM Corp. 1999, 2012
   5  *    Author(s): Hartmut Penner (hp@de.ibm.com),
   6  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   7  *
   8  *  Derived from "arch/i386/kernel/setup.c"
   9  *    Copyright (C) 1995, Linus Torvalds
  10  */
  11
  12 /*
  13  * This file handles the architecture-dependent parts of initialization
  14  */
  15
  16 #define KMSG_COMPONENT "setup"
  17 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  18
  19 #include <linux/errno.h>
  20 #include <linux/export.h>
  21 #include <linux/sched.h>
  22 #include <linux/sched/task.h>
  23 #include <linux/cpu.h>
  24 #include <linux/kernel.h>
  25 #include <linux/memblock.h>
  26 #include <linux/mm.h>
  27 #include <linux/stddef.h>
  28 #include <linux/unistd.h>
  29 #include <linux/ptrace.h>
  30 #include <linux/random.h>
  31 #include <linux/user.h>
  32 #include <linux/tty.h>
  33 #include <linux/ioport.h>
  34 #include <linux/delay.h>
  35 #include <linux/init.h>
  36 #include <linux/initrd.h>
  37 #include <linux/root_dev.h>
  38 #include <linux/console.h>
  39 #include <linux/kernel_stat.h>
  40 #include <linux/dma-contiguous.h>
  41 #include <linux/device.h>
  42 #include <linux/notifier.h>
  43 #include <linux/pfn.h>
  44 #include <linux/ctype.h>
  45 #include <linux/reboot.h>
  46 #include <linux/topology.h>
  47 #include <linux/kexec.h>
  48 #include <linux/crash_dump.h>
  49 #include <linux/memory.h>
  50 #include <linux/compat.h>
  51 #include <linux/start_kernel.h>
  52
  53 #include <asm/boot_data.h>
  54 #include <asm/ipl.h>
  55 #include <asm/facility.h>
  56 #include <asm/smp.h>
  57 #include <asm/mmu_context.h>
  58 #include <asm/cpcmd.h>
  59 #include <asm/lowcore.h>
  60 #include <asm/nmi.h>
  61 #include <asm/irq.h>
  62 #include <asm/page.h>
  63 #include <asm/ptrace.h>
  64 #include <asm/sections.h>
  65 #include <asm/ebcdic.h>
  66 #include <asm/diag.h>
  67 #include <asm/os_info.h>
  68 #include <asm/sclp.h>
  69 #include <asm/stacktrace.h>
  70 #include <asm/sysinfo.h>
  71 #include <asm/numa.h>
  72 #include <asm/alternative.h>
  73 #include <asm/nospec-branch.h>
  74 #include <asm/mem_detect.h>
  75 #include <asm/uv.h>
  76 #include "entry.h"
  77
  78 /*
  79  * Machine setup..
  80  */
  81 unsigned int console_mode = 0;
  82 EXPORT_SYMBOL(console_mode);
  83
  84 unsigned int console_devno = -1;
  85 EXPORT_SYMBOL(console_devno);
  86
  87 unsigned int console_irq = -1;
  88 EXPORT_SYMBOL(console_irq);
  89
  90 unsigned long elf_hwcap __read_mostly = 0;
  91 char elf_platform[ELF_PLATFORM_SIZE];
  92
  93 unsigned long int_hwcap = 0;
  94
  95 #ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
  96 int __bootdata_preserved(prot_virt_guest);
  97 #endif
  98
  99 int __bootdata(noexec_disabled);
 100 int __bootdata(memory_end_set);
 101 unsigned long __bootdata(memory_end);
 102 unsigned long __bootdata(vmalloc_size);
 103 unsigned long __bootdata(max_physmem_end);
 104 struct mem_detect_info __bootdata(mem_detect);
 105
 106 struct exception_table_entry *__bootdata_preserved(__start_dma_ex_table);
 107 struct exception_table_entry *__bootdata_preserved(__stop_dma_ex_table);
 108 unsigned long __bootdata_preserved(__swsusp_reset_dma);
 109 unsigned long __bootdata_preserved(__stext_dma);
 110 unsigned long __bootdata_preserved(__etext_dma);
 111 unsigned long __bootdata_preserved(__sdma);
 112 unsigned long __bootdata_preserved(__edma);
 113 unsigned long __bootdata_preserved(__kaslr_offset);
 114
 115 unsigned long VMALLOC_START;
 116 EXPORT_SYMBOL(VMALLOC_START);
 117
 118 unsigned long VMALLOC_END;
 119 EXPORT_SYMBOL(VMALLOC_END);
 120
 121 struct page *vmemmap;
 122 EXPORT_SYMBOL(vmemmap);
 123
 124 unsigned long MODULES_VADDR;
 125 unsigned long MODULES_END;
 126
 127 /* An array with a pointer to the lowcore of every CPU. */
 128 struct lowcore *lowcore_ptr[NR_CPUS];
 129 EXPORT_SYMBOL(lowcore_ptr);
 130
 131 /*
 132  * This is set up by the setup-routine at boot-time
 133  * for S390 need to find out, what we have to setup
 134  * using address 0x10400 ...
 135  */
 136
 137 #include <asm/setup.h>
 138
 139 /*
 140  * condev= and conmode= setup parameter.
 141  */
 142
 143 static int __init condev_setup(char *str)
 144 {
 145         int vdev;
 146
 147         vdev = simple_strtoul(str, &str, 0);
 148         if (vdev >= 0 && vdev < 65536) {
 149                 console_devno = vdev;
 150                 console_irq = -1;
 151         }
 152         return 1;
 153 }
 154
 155 __setup("condev=", condev_setup);
 156
 157 static void __init set_preferred_console(void)
 158 {
 159         if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
 160                 add_preferred_console("ttyS", 0, NULL);
 161         else if (CONSOLE_IS_3270)
 162                 add_preferred_console("tty3270", 0, NULL);
 163         else if (CONSOLE_IS_VT220)
 164                 add_preferred_console("ttyS", 1, NULL);
 165         else if (CONSOLE_IS_HVC)
 166                 add_preferred_console("hvc", 0, NULL);
 167 }
 168
 169 static int __init conmode_setup(char *str)
 170 {
 171 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 172         if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
 173                 SET_CONSOLE_SCLP;
 174 #endif
 175 #if defined(CONFIG_TN3215_CONSOLE)
 176         if (!strcmp(str, "3215"))
 177                 SET_CONSOLE_3215;
 178 #endif
 179 #if defined(CONFIG_TN3270_CONSOLE)
 180         if (!strcmp(str, "3270"))
 181                 SET_CONSOLE_3270;
 182 #endif
 183         set_preferred_console();
 184         return 1;
 185 }
 186
 187 __setup("conmode=", conmode_setup);
 188
 189 static void __init conmode_default(void)
 190 {
 191         char query_buffer[1024];
 192         char *ptr;
 193
 194         if (MACHINE_IS_VM) {
 195                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 196                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 197                 ptr = strstr(query_buffer, "SUBCHANNEL =");
 198                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
 199                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 200                 ptr = strstr(query_buffer, "CONMODE");
 201                 /*
 202                  * Set the conmode to 3215 so that the device recognition
 203                  * will set the cu_type of the console to 3215. If the
 204                  * conmode is 3270 and we don't set it back then both
 205                  * 3215 and the 3270 driver will try to access the console
 206                  * device (3215 as console and 3270 as normal tty).
 207                  */
 208                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 209                 if (ptr == NULL) {
 210 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 211                         SET_CONSOLE_SCLP;
 212 #endif
 213                         return;
 214                 }
 215                 if (str_has_prefix(ptr + 8, "3270")) {
 216 #if defined(CONFIG_TN3270_CONSOLE)
 217                         SET_CONSOLE_3270;
 218 #elif defined(CONFIG_TN3215_CONSOLE)
 219                         SET_CONSOLE_3215;
 220 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 221                         SET_CONSOLE_SCLP;
 222 #endif
 223                 } else if (str_has_prefix(ptr + 8, "3215")) {
 224 #if defined(CONFIG_TN3215_CONSOLE)
 225                         SET_CONSOLE_3215;
 226 #elif defined(CONFIG_TN3270_CONSOLE)
 227                         SET_CONSOLE_3270;
 228 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 229                         SET_CONSOLE_SCLP;
 230 #endif
 231                 }
 232         } else if (MACHINE_IS_KVM) {
 233                 if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
 234                         SET_CONSOLE_VT220;
 235                 else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
 236                         SET_CONSOLE_SCLP;
 237                 else
 238                         SET_CONSOLE_HVC;
 239         } else {
 240 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 241                 SET_CONSOLE_SCLP;
 242 #endif
 243         }
 244         if (IS_ENABLED(CONFIG_VT) && IS_ENABLED(CONFIG_DUMMY_CONSOLE))
 245                 conswitchp = &dummy_con;
 246 }
 247
 248 #ifdef CONFIG_CRASH_DUMP
 249 static void __init setup_zfcpdump(void)
 250 {
 251         if (ipl_info.type != IPL_TYPE_FCP_DUMP)
 252                 return;
 253         if (OLDMEM_BASE)
 254                 return;
 255         strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
 256         console_loglevel = 2;
 257 }
 258 #else
 259 static inline void setup_zfcpdump(void) {}
 260 #endif /* CONFIG_CRASH_DUMP */
 261
 262  /*
 263  * Reboot, halt and power_off stubs. They just call _machine_restart,
 264  * _machine_halt or _machine_power_off.
 265  */
 266
 267 void machine_restart(char *command)
 268 {
 269         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 270                 /*
 271                  * Only unblank the console if we are called in enabled
 272                  * context or a bust_spinlocks cleared the way for us.
 273                  */
 274                 console_unblank();
 275         _machine_restart(command);
 276 }
 277
 278 void machine_halt(void)
 279 {
 280         if (!in_interrupt() || oops_in_progress)
 281                 /*
 282                  * Only unblank the console if we are called in enabled
 283                  * context or a bust_spinlocks cleared the way for us.
 284                  */
 285                 console_unblank();
 286         _machine_halt();
 287 }
 288
 289 void machine_power_off(void)
 290 {
 291         if (!in_interrupt() || oops_in_progress)
 292                 /*
 293                  * Only unblank the console if we are called in enabled
 294                  * context or a bust_spinlocks cleared the way for us.
 295                  */
 296                 console_unblank();
 297         _machine_power_off();
 298 }
 299
 300 /*
 301  * Dummy power off function.
 302  */
 303 void (*pm_power_off)(void) = machine_power_off;
 304 EXPORT_SYMBOL_GPL(pm_power_off);
 305
 306 void *restart_stack __section(.data);
 307
 308 unsigned long stack_alloc(void)
 309 {
 310 #ifdef CONFIG_VMAP_STACK
 311         return (unsigned long)
 312                 __vmalloc_node_range(THREAD_SIZE, THREAD_SIZE,
 313                                      VMALLOC_START, VMALLOC_END,
 314                                      THREADINFO_GFP,
 315                                      PAGE_KERNEL, 0, NUMA_NO_NODE,
 316                                      __builtin_return_address(0));
 317 #else
 318         return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
 319 #endif
 320 }
 321
 322 void stack_free(unsigned long stack)
 323 {
 324 #ifdef CONFIG_VMAP_STACK
 325         vfree((void *) stack);
 326 #else
 327         free_pages(stack, THREAD_SIZE_ORDER);
 328 #endif
 329 }
 330
 331 int __init arch_early_irq_init(void)
 332 {
 333         unsigned long stack;
 334
 335         stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
 336         if (!stack)
 337                 panic("Couldn't allocate async stack");
 338         S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
 339         return 0;
 340 }
 341
 342 static int __init async_stack_realloc(void)
 343 {
 344         unsigned long old, new;
 345
 346         old = S390_lowcore.async_stack - STACK_INIT_OFFSET;
 347         new = stack_alloc();
 348         if (!new)
 349                 panic("Couldn't allocate async stack");
 350         S390_lowcore.async_stack = new + STACK_INIT_OFFSET;
 351         free_pages(old, THREAD_SIZE_ORDER);
 352         return 0;
 353 }
 354 early_initcall(async_stack_realloc);
 355
 356 void __init arch_call_rest_init(void)
 357 {
 358         struct stack_frame *frame;
 359         unsigned long stack;
 360
 361         stack = stack_alloc();
 362         if (!stack)
 363                 panic("Couldn't allocate kernel stack");
 364         current->stack = (void *) stack;
 365 #ifdef CONFIG_VMAP_STACK
 366         current->stack_vm_area = (void *) stack;
 367 #endif
 368         set_task_stack_end_magic(current);
 369         stack += STACK_INIT_OFFSET;
 370         S390_lowcore.kernel_stack = stack;
 371         frame = (struct stack_frame *) stack;
 372         memset(frame, 0, sizeof(*frame));
 373         /* Branch to rest_init on the new stack, never returns */
 374         asm volatile(
 375                 "       la      15,0(%[_frame])\n"
 376                 "       jg      rest_init\n"
 377                 : : [_frame] "a" (frame));
 378 }
 379
 380 static void __init setup_lowcore_dat_off(void)
 381 {
 382         struct lowcore *lc;
 383
 384         /*
 385          * Setup lowcore for boot cpu
 386          */
 387         BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
 388         lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
 389         if (!lc)
 390                 panic("%s: Failed to allocate %zu bytes align=%zx\n",
 391                       __func__, sizeof(*lc), sizeof(*lc));
 392
 393         lc->restart_psw.mask = PSW_KERNEL_BITS;
 394         lc->restart_psw.addr = (unsigned long) restart_int_handler;
 395         lc->external_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
 396         lc->external_new_psw.addr = (unsigned long) ext_int_handler;
 397         lc->svc_new_psw.mask = PSW_KERNEL_BITS |
 398                 PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
 399         lc->svc_new_psw.addr = (unsigned long) system_call;
 400         lc->program_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
 401         lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
 402         lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
 403         lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
 404         lc->io_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK;
 405         lc->io_new_psw.addr = (unsigned long) io_int_handler;
 406         lc->clock_comparator = clock_comparator_max;
 407         lc->nodat_stack = ((unsigned long) &init_thread_union)
 408                 + THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
 409         lc->current_task = (unsigned long)&init_task;
 410         lc->lpp = LPP_MAGIC;
 411         lc->machine_flags = S390_lowcore.machine_flags;
 412         lc->preempt_count = S390_lowcore.preempt_count;
 413         lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
 414         memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
 415                sizeof(lc->stfle_fac_list));
 416         memcpy(lc->alt_stfle_fac_list, S390_lowcore.alt_stfle_fac_list,
 417                sizeof(lc->alt_stfle_fac_list));
 418         nmi_alloc_boot_cpu(lc);
 419         vdso_alloc_boot_cpu(lc);
 420         lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
 421         lc->async_enter_timer = S390_lowcore.async_enter_timer;
 422         lc->exit_timer = S390_lowcore.exit_timer;
 423         lc->user_timer = S390_lowcore.user_timer;
 424         lc->system_timer = S390_lowcore.system_timer;
 425         lc->steal_timer = S390_lowcore.steal_timer;
 426         lc->last_update_timer = S390_lowcore.last_update_timer;
 427         lc->last_update_clock = S390_lowcore.last_update_clock;
 428
 429         /*
 430          * Allocate the global restart stack which is the same for
 431          * all CPUs in cast *one* of them does a PSW restart.
 432          */
 433         restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
 434         if (!restart_stack)
 435                 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
 436                       __func__, THREAD_SIZE, THREAD_SIZE);
 437         restart_stack += STACK_INIT_OFFSET;
 438
 439         /*
 440          * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
 441          * restart data to the absolute zero lowcore. This is necessary if
 442          * PSW restart is done on an offline CPU that has lowcore zero.
 443          */
 444         lc->restart_stack = (unsigned long) restart_stack;
 445         lc->restart_fn = (unsigned long) do_restart;
 446         lc->restart_data = 0;
 447         lc->restart_source = -1UL;
 448
 449         /* Setup absolute zero lowcore */
 450         mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
 451         mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
 452         mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
 453         mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
 454         mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
 455
 456         lc->spinlock_lockval = arch_spin_lockval(0);
 457         lc->spinlock_index = 0;
 458         arch_spin_lock_setup(0);
 459         lc->br_r1_trampoline = 0x07f1;  /* br %r1 */
 460
 461         set_prefix((u32)(unsigned long) lc);
 462         lowcore_ptr[0] = lc;
 463 }
 464
 465 static void __init setup_lowcore_dat_on(void)
 466 {
 467         __ctl_clear_bit(0, 28);
 468         S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
 469         S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
 470         S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
 471         S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
 472         __ctl_set_bit(0, 28);
 473 }
 474
 475 static struct resource code_resource = {
 476         .name  = "Kernel code",
 477         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 478 };
 479
 480 static struct resource data_resource = {
 481         .name = "Kernel data",
 482         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 483 };
 484
 485 static struct resource bss_resource = {
 486         .name = "Kernel bss",
 487         .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 488 };
 489
 490 static struct resource __initdata *standard_resources[] = {
 491         &code_resource,
 492         &data_resource,
 493         &bss_resource,
 494 };
 495
 496 static void __init setup_resources(void)
 497 {
 498         struct resource *res, *std_res, *sub_res;
 499         struct memblock_region *reg;
 500         int j;
 501
 502         code_resource.start = (unsigned long) _text;
 503         code_resource.end = (unsigned long) _etext - 1;
 504         data_resource.start = (unsigned long) _etext;
 505         data_resource.end = (unsigned long) _edata - 1;
 506         bss_resource.start = (unsigned long) __bss_start;
 507         bss_resource.end = (unsigned long) __bss_stop - 1;
 508
 509         for_each_memblock(memory, reg) {
 510                 res = memblock_alloc(sizeof(*res), 8);
 511                 if (!res)
 512                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 513                               __func__, sizeof(*res), 8);
 514                 res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
 515
 516                 res->name = "System RAM";
 517                 res->start = reg->base;
 518                 res->end = reg->base + reg->size - 1;
 519                 request_resource(&iomem_resource, res);
 520
 521                 for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 522                         std_res = standard_resources[j];
 523                         if (std_res->start < res->start ||
 524                             std_res->start > res->end)
 525                                 continue;
 526                         if (std_res->end > res->end) {
 527                                 sub_res = memblock_alloc(sizeof(*sub_res), 8);
 528                                 if (!sub_res)
 529                                         panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 530                                               __func__, sizeof(*sub_res), 8);
 531                                 *sub_res = *std_res;
 532                                 sub_res->end = res->end;
 533                                 std_res->start = res->end + 1;
 534                                 request_resource(res, sub_res);
 535                         } else {
 536                                 request_resource(res, std_res);
 537                         }
 538                 }
 539         }
 540 #ifdef CONFIG_CRASH_DUMP
 541         /*
 542          * Re-add removed crash kernel memory as reserved memory. This makes
 543          * sure it will be mapped with the identity mapping and struct pages
 544          * will be created, so it can be resized later on.
 545          * However add it later since the crash kernel resource should not be
 546          * part of the System RAM resource.
 547          */
 548         if (crashk_res.end) {
 549                 memblock_add_node(crashk_res.start, resource_size(&crashk_res), 0);
 550                 memblock_reserve(crashk_res.start, resource_size(&crashk_res));
 551                 insert_resource(&iomem_resource, &crashk_res);
 552         }
 553 #endif
 554 }
 555
 556 static void __init setup_memory_end(void)
 557 {
 558         unsigned long vmax, tmp;
 559
 560         /* Choose kernel address space layout: 3 or 4 levels. */
 561         if (IS_ENABLED(CONFIG_KASAN)) {
 562                 vmax = IS_ENABLED(CONFIG_KASAN_S390_4_LEVEL_PAGING)
 563                            ? _REGION1_SIZE
 564                            : _REGION2_SIZE;
 565         } else {
 566                 tmp = (memory_end ?: max_physmem_end) / PAGE_SIZE;
 567                 tmp = tmp * (sizeof(struct page) + PAGE_SIZE);
 568                 if (tmp + vmalloc_size + MODULES_LEN <= _REGION2_SIZE)
 569                         vmax = _REGION2_SIZE; /* 3-level kernel page table */
 570                 else
 571                         vmax = _REGION1_SIZE; /* 4-level kernel page table */
 572         }
 573
 574         /* module area is at the end of the kernel address space. */
 575         MODULES_END = vmax;
 576         MODULES_VADDR = MODULES_END - MODULES_LEN;
 577         VMALLOC_END = MODULES_VADDR;
 578         VMALLOC_START = VMALLOC_END - vmalloc_size;
 579
 580         /* Split remaining virtual space between 1:1 mapping & vmemmap array */
 581         tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
 582         /* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
 583         tmp = SECTION_ALIGN_UP(tmp);
 584         tmp = VMALLOC_START - tmp * sizeof(struct page);
 585         tmp &= ~((vmax >> 11) - 1);     /* align to page table level */
 586         tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
 587         vmemmap = (struct page *) tmp;
 588
 589         /* Take care that memory_end is set and <= vmemmap */
 590         memory_end = min(memory_end ?: max_physmem_end, (unsigned long)vmemmap);
 591 #ifdef CONFIG_KASAN
 592         /* fit in kasan shadow memory region between 1:1 and vmemmap */
 593         memory_end = min(memory_end, KASAN_SHADOW_START);
 594         vmemmap = max(vmemmap, (struct page *)KASAN_SHADOW_END);
 595 #endif
 596         max_pfn = max_low_pfn = PFN_DOWN(memory_end);
 597         memblock_remove(memory_end, ULONG_MAX);
 598
 599         pr_notice("The maximum memory size is %luMB\n", memory_end >> 20);
 600 }
 601
 602 #ifdef CONFIG_CRASH_DUMP
 603
 604 /*
 605  * When kdump is enabled, we have to ensure that no memory from
 606  * the area [0 - crashkernel memory size] and
 607  * [crashk_res.start - crashk_res.end] is set offline.
 608  */
 609 static int kdump_mem_notifier(struct notifier_block *nb,
 610                               unsigned long action, void *data)
 611 {
 612         struct memory_notify *arg = data;
 613
 614         if (action != MEM_GOING_OFFLINE)
 615                 return NOTIFY_OK;
 616         if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
 617                 return NOTIFY_BAD;
 618         if (arg->start_pfn > PFN_DOWN(crashk_res.end))
 619                 return NOTIFY_OK;
 620         if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
 621                 return NOTIFY_OK;
 622         return NOTIFY_BAD;
 623 }
 624
 625 static struct notifier_block kdump_mem_nb = {
 626         .notifier_call = kdump_mem_notifier,
 627 };
 628
 629 #endif
 630
 631 /*
 632  * Make sure that the area behind memory_end is protected
 633  */
 634 static void reserve_memory_end(void)
 635 {
 636         if (memory_end_set)
 637                 memblock_reserve(memory_end, ULONG_MAX);
 638 }
 639
 640 /*
 641  * Make sure that oldmem, where the dump is stored, is protected
 642  */
 643 static void reserve_oldmem(void)
 644 {
 645 #ifdef CONFIG_CRASH_DUMP
 646         if (OLDMEM_BASE)
 647                 /* Forget all memory above the running kdump system */
 648                 memblock_reserve(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
 649 #endif
 650 }
 651
 652 /*
 653  * Make sure that oldmem, where the dump is stored, is protected
 654  */
 655 static void remove_oldmem(void)
 656 {
 657 #ifdef CONFIG_CRASH_DUMP
 658         if (OLDMEM_BASE)
 659                 /* Forget all memory above the running kdump system */
 660                 memblock_remove(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
 661 #endif
 662 }
 663
 664 /*
 665  * Reserve memory for kdump kernel to be loaded with kexec
 666  */
 667 static void __init reserve_crashkernel(void)
 668 {
 669 #ifdef CONFIG_CRASH_DUMP
 670         unsigned long long crash_base, crash_size;
 671         phys_addr_t low, high;
 672         int rc;
 673
 674         rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
 675                                &crash_base);
 676
 677         crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
 678         crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
 679         if (rc || crash_size == 0)
 680                 return;
 681
 682         if (memblock.memory.regions[0].size < crash_size) {
 683                 pr_info("crashkernel reservation failed: %s\n",
 684                         "first memory chunk must be at least crashkernel size");
 685                 return;
 686         }
 687
 688         low = crash_base ?: OLDMEM_BASE;
 689         high = low + crash_size;
 690         if (low >= OLDMEM_BASE && high <= OLDMEM_BASE + OLDMEM_SIZE) {
 691                 /* The crashkernel fits into OLDMEM, reuse OLDMEM */
 692                 crash_base = low;
 693         } else {
 694                 /* Find suitable area in free memory */
 695                 low = max_t(unsigned long, crash_size, sclp.hsa_size);
 696                 high = crash_base ? crash_base + crash_size : ULONG_MAX;
 697
 698                 if (crash_base && crash_base < low) {
 699                         pr_info("crashkernel reservation failed: %s\n",
 700                                 "crash_base too low");
 701                         return;
 702                 }
 703                 low = crash_base ?: low;
 704                 crash_base = memblock_find_in_range(low, high, crash_size,
 705                                                     KEXEC_CRASH_MEM_ALIGN);
 706         }
 707
 708         if (!crash_base) {
 709                 pr_info("crashkernel reservation failed: %s\n",
 710                         "no suitable area found");
 711                 return;
 712         }
 713
 714         if (register_memory_notifier(&kdump_mem_nb))
 715                 return;
 716
 717         if (!OLDMEM_BASE && MACHINE_IS_VM)
 718                 diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
 719         crashk_res.start = crash_base;
 720         crashk_res.end = crash_base + crash_size - 1;
 721         memblock_remove(crash_base, crash_size);
 722         pr_info("Reserving %lluMB of memory at %lluMB "
 723                 "for crashkernel (System RAM: %luMB)\n",
 724                 crash_size >> 20, crash_base >> 20,
 725                 (unsigned long)memblock.memory.total_size >> 20);
 726         os_info_crashkernel_add(crash_base, crash_size);
 727 #endif
 728 }
 729
 730 /*
 731  * Reserve the initrd from being used by memblock
 732  */
 733 static void __init reserve_initrd(void)
 734 {
 735 #ifdef CONFIG_BLK_DEV_INITRD
 736         if (!INITRD_START || !INITRD_SIZE)
 737                 return;
 738         initrd_start = INITRD_START;
 739         initrd_end = initrd_start + INITRD_SIZE;
 740         memblock_reserve(INITRD_START, INITRD_SIZE);
 741 #endif
 742 }
 743
 744 /*
 745  * Reserve the memory area used to pass the certificate lists
 746  */
 747 static void __init reserve_certificate_list(void)
 748 {
 749         if (ipl_cert_list_addr)
 750                 memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
 751 }
 752
 753 static void __init reserve_mem_detect_info(void)
 754 {
 755         unsigned long start, size;
 756
 757         get_mem_detect_reserved(&start, &size);
 758         if (size)
 759                 memblock_reserve(start, size);
 760 }
 761
 762 static void __init free_mem_detect_info(void)
 763 {
 764         unsigned long start, size;
 765
 766         get_mem_detect_reserved(&start, &size);
 767         if (size)
 768                 memblock_free(start, size);
 769 }
 770
 771 static void __init memblock_physmem_add(phys_addr_t start, phys_addr_t size)
 772 {
 773         memblock_dbg("memblock_physmem_add: [%#016llx-%#016llx]\n",
 774                      start, start + size - 1);
 775         memblock_add_range(&memblock.memory, start, size, 0, 0);
 776         memblock_add_range(&memblock.physmem, start, size, 0, 0);
 777 }
 778
 779 static const char * __init get_mem_info_source(void)
 780 {
 781         switch (mem_detect.info_source) {
 782         case MEM_DETECT_SCLP_STOR_INFO:
 783                 return "sclp storage info";
 784         case MEM_DETECT_DIAG260:
 785                 return "diag260";
 786         case MEM_DETECT_SCLP_READ_INFO:
 787                 return "sclp read info";
 788         case MEM_DETECT_BIN_SEARCH:
 789                 return "binary search";
 790         }
 791         return "none";
 792 }
 793
 794 static void __init memblock_add_mem_detect_info(void)
 795 {
 796         unsigned long start, end;
 797         int i;
 798
 799         memblock_dbg("physmem info source: %s (%hhd)\n",
 800                      get_mem_info_source(), mem_detect.info_source);
 801         /* keep memblock lists close to the kernel */
 802         memblock_set_bottom_up(true);
 803         for_each_mem_detect_block(i, &start, &end)
 804                 memblock_physmem_add(start, end - start);
 805         memblock_set_bottom_up(false);
 806         memblock_dump_all();
 807 }
 808
 809 /*
 810  * Check for initrd being in usable memory
 811  */
 812 static void __init check_initrd(void)
 813 {
 814 #ifdef CONFIG_BLK_DEV_INITRD
 815         if (INITRD_START && INITRD_SIZE &&
 816             !memblock_is_region_memory(INITRD_START, INITRD_SIZE)) {
 817                 pr_err("The initial RAM disk does not fit into the memory\n");
 818                 memblock_free(INITRD_START, INITRD_SIZE);
 819                 initrd_start = initrd_end = 0;
 820         }
 821 #endif
 822 }
 823
 824 /*
 825  * Reserve memory used for lowcore/command line/kernel image.
 826  */
 827 static void __init reserve_kernel(void)
 828 {
 829         unsigned long start_pfn = PFN_UP(__pa(_end));
 830
 831         memblock_reserve(0, HEAD_END);
 832         memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
 833                          - (unsigned long)_stext);
 834         memblock_reserve(__sdma, __edma - __sdma);
 835 }
 836
 837 static void __init setup_memory(void)
 838 {
 839         struct memblock_region *reg;
 840
 841         /*
 842          * Init storage key for present memory
 843          */
 844         for_each_memblock(memory, reg) {
 845                 storage_key_init_range(reg->base, reg->base + reg->size);
 846         }
 847         psw_set_key(PAGE_DEFAULT_KEY);
 848
 849         /* Only cosmetics */
 850         memblock_enforce_memory_limit(memblock_end_of_DRAM());
 851 }
 852
 853 /*
 854  * Setup hardware capabilities.
 855  */
 856 static int __init setup_hwcaps(void)
 857 {
 858         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
 859         struct cpuid cpu_id;
 860         int i;
 861
 862         /*
 863          * The store facility list bits numbers as found in the principles
 864          * of operation are numbered with bit 1UL<<31 as number 0 to
 865          * bit 1UL<<0 as number 31.
 866          *   Bit 0: instructions named N3, "backported" to esa-mode
 867          *   Bit 2: z/Architecture mode is active
 868          *   Bit 7: the store-facility-list-extended facility is installed
 869          *   Bit 17: the message-security assist is installed
 870          *   Bit 19: the long-displacement facility is installed
 871          *   Bit 21: the extended-immediate facility is installed
 872          *   Bit 22: extended-translation facility 3 is installed
 873          *   Bit 30: extended-translation facility 3 enhancement facility
 874          * These get translated to:
 875          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
 876          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
 877          *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
 878          *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
 879          */
 880         for (i = 0; i < 6; i++)
 881                 if (test_facility(stfl_bits[i]))
 882                         elf_hwcap |= 1UL << i;
 883
 884         if (test_facility(22) && test_facility(30))
 885                 elf_hwcap |= HWCAP_S390_ETF3EH;
 886
 887         /*
 888          * Check for additional facilities with store-facility-list-extended.
 889          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
 890          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
 891          * as stored by stfl, bits 32-xxx contain additional facilities.
 892          * How many facility words are stored depends on the number of
 893          * doublewords passed to the instruction. The additional facilities
 894          * are:
 895          *   Bit 42: decimal floating point facility is installed
 896          *   Bit 44: perform floating point operation facility is installed
 897          * translated to:
 898          *   HWCAP_S390_DFP bit 6 (42 && 44).
 899          */
 900         if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
 901                 elf_hwcap |= HWCAP_S390_DFP;
 902
 903         /*
 904          * Huge page support HWCAP_S390_HPAGE is bit 7.
 905          */
 906         if (MACHINE_HAS_EDAT1)
 907                 elf_hwcap |= HWCAP_S390_HPAGE;
 908
 909         /*
 910          * 64-bit register support for 31-bit processes
 911          * HWCAP_S390_HIGH_GPRS is bit 9.
 912          */
 913         elf_hwcap |= HWCAP_S390_HIGH_GPRS;
 914
 915         /*
 916          * Transactional execution support HWCAP_S390_TE is bit 10.
 917          */
 918         if (MACHINE_HAS_TE)
 919                 elf_hwcap |= HWCAP_S390_TE;
 920
 921         /*
 922          * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension
 923          * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX
 924          * instead of facility bit 129.
 925          */
 926         if (MACHINE_HAS_VX) {
 927                 elf_hwcap |= HWCAP_S390_VXRS;
 928                 if (test_facility(134))
 929                         elf_hwcap |= HWCAP_S390_VXRS_EXT;
 930                 if (test_facility(135))
 931                         elf_hwcap |= HWCAP_S390_VXRS_BCD;
 932                 if (test_facility(148))
 933                         elf_hwcap |= HWCAP_S390_VXRS_EXT2;
 934                 if (test_facility(152))
 935                         elf_hwcap |= HWCAP_S390_VXRS_PDE;
 936         }
 937         if (test_facility(150))
 938                 elf_hwcap |= HWCAP_S390_SORT;
 939         if (test_facility(151))
 940                 elf_hwcap |= HWCAP_S390_DFLT;
 941
 942         /*
 943          * Guarded storage support HWCAP_S390_GS is bit 12.
 944          */
 945         if (MACHINE_HAS_GS)
 946                 elf_hwcap |= HWCAP_S390_GS;
 947
 948         get_cpu_id(&cpu_id);
 949         add_device_randomness(&cpu_id, sizeof(cpu_id));
 950         switch (cpu_id.machine) {
 951         case 0x2064:
 952         case 0x2066:
 953         default:        /* Use "z900" as default for 64 bit kernels. */
 954                 strcpy(elf_platform, "z900");
 955                 break;
 956         case 0x2084:
 957         case 0x2086:
 958                 strcpy(elf_platform, "z990");
 959                 break;
 960         case 0x2094:
 961         case 0x2096:
 962                 strcpy(elf_platform, "z9-109");
 963                 break;
 964         case 0x2097:
 965         case 0x2098:
 966                 strcpy(elf_platform, "z10");
 967                 break;
 968         case 0x2817:
 969         case 0x2818:
 970                 strcpy(elf_platform, "z196");
 971                 break;
 972         case 0x2827:
 973         case 0x2828:
 974                 strcpy(elf_platform, "zEC12");
 975                 break;
 976         case 0x2964:
 977         case 0x2965:
 978                 strcpy(elf_platform, "z13");
 979                 break;
 980         case 0x3906:
 981         case 0x3907:
 982                 strcpy(elf_platform, "z14");
 983                 break;
 984         case 0x8561:
 985         case 0x8562:
 986                 strcpy(elf_platform, "z15");
 987                 break;
 988         }
 989
 990         /*
 991          * Virtualization support HWCAP_INT_SIE is bit 0.
 992          */
 993         if (sclp.has_sief2)
 994                 int_hwcap |= HWCAP_INT_SIE;
 995
 996         return 0;
 997 }
 998 arch_initcall(setup_hwcaps);
 999
1000 /*
1001  * Add system information as device randomness
1002  */
1003 static void __init setup_randomness(void)
1004 {
1005         struct sysinfo_3_2_2 *vmms;
1006
1007         vmms = (struct sysinfo_3_2_2 *) memblock_phys_alloc(PAGE_SIZE,
1008                                                             PAGE_SIZE);
1009         if (!vmms)
1010                 panic("Failed to allocate memory for sysinfo structure\n");
1011
1012         if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
1013                 add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
1014         memblock_free((unsigned long) vmms, PAGE_SIZE);
1015 }
1016
1017 /*
1018  * Find the correct size for the task_struct. This depends on
1019  * the size of the struct fpu at the end of the thread_struct
1020  * which is embedded in the task_struct.
1021  */
1022 static void __init setup_task_size(void)
1023 {
1024         int task_size = sizeof(struct task_struct);
1025
1026         if (!MACHINE_HAS_VX) {
1027                 task_size -= sizeof(__vector128) * __NUM_VXRS;
1028                 task_size += sizeof(freg_t) * __NUM_FPRS;
1029         }
1030         arch_task_struct_size = task_size;
1031 }
1032
1033 /*
1034  * Issue diagnose 318 to set the control program name and
1035  * version codes.
1036  */
1037 static void __init setup_control_program_code(void)
1038 {
1039         union diag318_info diag318_info = {
1040                 .cpnc = CPNC_LINUX,
1041                 .cpvc_linux = 0,
1042                 .cpvc_distro = {0},
1043         };
1044
1045         if (!sclp.has_diag318)
1046                 return;
1047
1048         diag_stat_inc(DIAG_STAT_X318);
1049         asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
1050 }
1051
1052 /*
1053  * Print the component list from the IPL report
1054  */
1055 static void __init log_component_list(void)
1056 {
1057         struct ipl_rb_component_entry *ptr, *end;
1058         char *str;
1059
1060         if (!early_ipl_comp_list_addr)
1061                 return;
1062         if (ipl_block.hdr.flags & IPL_PL_FLAG_IPLSR)
1063                 pr_info("Linux is running with Secure-IPL enabled\n");
1064         else
1065                 pr_info("Linux is running with Secure-IPL disabled\n");
1066         ptr = (void *) early_ipl_comp_list_addr;
1067         end = (void *) ptr + early_ipl_comp_list_size;
1068         pr_info("The IPL report contains the following components:\n");
1069         while (ptr < end) {
1070                 if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
1071                         if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
1072                                 str = "signed, verified";
1073                         else
1074                                 str = "signed, verification failed";
1075                 } else {
1076                         str = "not signed";
1077                 }
1078                 pr_info("%016llx - %016llx (%s)\n",
1079                         ptr->addr, ptr->addr + ptr->len, str);
1080                 ptr++;
1081         }
1082 }
1083
1084 /*
1085  * Setup function called from init/main.c just after the banner
1086  * was printed.
1087  */
1088
1089 void __init setup_arch(char **cmdline_p)
1090 {
1091         /*
1092          * print what head.S has found out about the machine
1093          */
1094         if (MACHINE_IS_VM)
1095                 pr_info("Linux is running as a z/VM "
1096                         "guest operating system in 64-bit mode\n");
1097         else if (MACHINE_IS_KVM)
1098                 pr_info("Linux is running under KVM in 64-bit mode\n");
1099         else if (MACHINE_IS_LPAR)
1100                 pr_info("Linux is running natively in 64-bit mode\n");
1101         else
1102                 pr_info("Linux is running as a guest in 64-bit mode\n");
1103
1104         log_component_list();
1105
1106         /* Have one command line that is parsed and saved in /proc/cmdline */
1107         /* boot_command_line has been already set up in early.c */
1108         *cmdline_p = boot_command_line;
1109
1110         ROOT_DEV = Root_RAM0;
1111
1112         init_mm.start_code = (unsigned long) _text;
1113         init_mm.end_code = (unsigned long) _etext;
1114         init_mm.end_data = (unsigned long) _edata;
1115         init_mm.brk = (unsigned long) _end;
1116
1117         if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
1118                 nospec_auto_detect();
1119
1120         parse_early_param();
1121 #ifdef CONFIG_CRASH_DUMP
1122         /* Deactivate elfcorehdr= kernel parameter */
1123         elfcorehdr_addr = ELFCORE_ADDR_MAX;
1124 #endif
1125
1126         os_info_init();
1127         setup_ipl();
1128         setup_task_size();
1129         setup_control_program_code();
1130
1131         /* Do some memory reservations *before* memory is added to memblock */
1132         reserve_memory_end();
1133         reserve_oldmem();
1134         reserve_kernel();
1135         reserve_initrd();
1136         reserve_certificate_list();
1137         reserve_mem_detect_info();
1138         memblock_allow_resize();
1139
1140         /* Get information about *all* installed memory */
1141         memblock_add_mem_detect_info();
1142
1143         free_mem_detect_info();
1144         remove_oldmem();
1145
1146         /*
1147          * Make sure all chunks are MAX_ORDER aligned so we don't need the
1148          * extra checks that HOLES_IN_ZONE would require.
1149          *
1150          * Is this still required?
1151          */
1152         memblock_trim_memory(1UL << (MAX_ORDER - 1 + PAGE_SHIFT));
1153
1154         setup_memory_end();
1155         setup_memory();
1156         dma_contiguous_reserve(memory_end);
1157         vmcp_cma_reserve();
1158
1159         check_initrd();
1160         reserve_crashkernel();
1161 #ifdef CONFIG_CRASH_DUMP
1162         /*
1163          * Be aware that smp_save_dump_cpus() triggers a system reset.
1164          * Therefore CPU and device initialization should be done afterwards.
1165          */
1166         smp_save_dump_cpus();
1167 #endif
1168
1169         setup_resources();
1170         setup_lowcore_dat_off();
1171         smp_fill_possible_mask();
1172         cpu_detect_mhz_feature();
1173         cpu_init();
1174         numa_setup();
1175         smp_detect_cpus();
1176         topology_init_early();
1177
1178         /*
1179          * Create kernel page tables and switch to virtual addressing.
1180          */
1181         paging_init();
1182
1183         /*
1184          * After paging_init created the kernel page table, the new PSWs
1185          * in lowcore can now run with DAT enabled.
1186          */
1187         setup_lowcore_dat_on();
1188
1189         /* Setup default console */
1190         conmode_default();
1191         set_preferred_console();
1192
1193         apply_alternative_instructions();
1194         if (IS_ENABLED(CONFIG_EXPOLINE))
1195                 nospec_init_branches();
1196
1197         /* Setup zfcpdump support */
1198         setup_zfcpdump();
1199
1200         /* Add system specific data to the random pool */
1201         setup_randomness();
1202 }