mm/init.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/arch/parisc/mm/init.c
   4  *
   5  *  Copyright (C) 1995  Linus Torvalds
   6  *  Copyright 1999 SuSE GmbH
   7  *    changed by Philipp Rumpf
   8  *  Copyright 1999 Philipp Rumpf (prumpf@tux.org)
   9  *  Copyright 2004 Randolph Chung (tausq@debian.org)
  10  *  Copyright 2006-2007 Helge Deller (deller@gmx.de)
  11  *
  12  */
  13
  14
  15 #include <linux/module.h>
  16 #include <linux/mm.h>
  17 #include <linux/memblock.h>
  18 #include <linux/gfp.h>
  19 #include <linux/delay.h>
  20 #include <linux/init.h>
  21 #include <linux/initrd.h>
  22 #include <linux/swap.h>
  23 #include <linux/unistd.h>
  24 #include <linux/nodemask.h>     /* for node_online_map */
  25 #include <linux/pagemap.h>      /* for release_pages */
  26 #include <linux/compat.h>
  27
  28 #include <asm/pgalloc.h>
  29 #include <asm/tlb.h>
  30 #include <asm/pdc_chassis.h>
  31 #include <asm/mmzone.h>
  32 #include <asm/sections.h>
  33 #include <asm/msgbuf.h>
  34 #include <asm/sparsemem.h>
  35 #include <asm/asm-offsets.h>
  36
  37 extern int  data_start;
  38 extern void parisc_kernel_start(void);  /* Kernel entry point in head.S */
  39
  40 #if CONFIG_PGTABLE_LEVELS == 3
  41 pmd_t pmd0[PTRS_PER_PMD] __section(".data..vm0.pmd") __attribute__ ((aligned(PAGE_SIZE)));
  42 #endif
  43
  44 pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(".data..vm0.pgd") __attribute__ ((aligned(PAGE_SIZE)));
  45 pte_t pg0[PT_INITIAL * PTRS_PER_PTE] __section(".data..vm0.pte") __attribute__ ((aligned(PAGE_SIZE)));
  46
  47 static struct resource data_resource = {
  48         .name   = "Kernel data",
  49         .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
  50 };
  51
  52 static struct resource code_resource = {
  53         .name   = "Kernel code",
  54         .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
  55 };
  56
  57 static struct resource pdcdata_resource = {
  58         .name   = "PDC data (Page Zero)",
  59         .start  = 0,
  60         .end    = 0x9ff,
  61         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM,
  62 };
  63
  64 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __ro_after_init;
  65
  66 /* The following array is initialized from the firmware specific
  67  * information retrieved in kernel/inventory.c.
  68  */
  69
  70 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __initdata;
  71 int npmem_ranges __initdata;
  72
  73 #ifdef CONFIG_64BIT
  74 #define MAX_MEM         (1UL << MAX_PHYSMEM_BITS)
  75 #else /* !CONFIG_64BIT */
  76 #define MAX_MEM         (3584U*1024U*1024U)
  77 #endif /* !CONFIG_64BIT */
  78
  79 static unsigned long mem_limit __read_mostly = MAX_MEM;
  80
  81 static void __init mem_limit_func(void)
  82 {
  83         char *cp, *end;
  84         unsigned long limit;
  85
  86         /* We need this before __setup() functions are called */
  87
  88         limit = MAX_MEM;
  89         for (cp = boot_command_line; *cp; ) {
  90                 if (memcmp(cp, "mem=", 4) == 0) {
  91                         cp += 4;
  92                         limit = memparse(cp, &end);
  93                         if (end != cp)
  94                                 break;
  95                         cp = end;
  96                 } else {
  97                         while (*cp != ' ' && *cp)
  98                                 ++cp;
  99                         while (*cp == ' ')
 100                                 ++cp;
 101                 }
 102         }
 103
 104         if (limit < mem_limit)
 105                 mem_limit = limit;
 106 }
 107
 108 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT)
 109
 110 static void __init setup_bootmem(void)
 111 {
 112         unsigned long mem_max;
 113 #ifndef CONFIG_SPARSEMEM
 114         physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1];
 115         int npmem_holes;
 116 #endif
 117         int i, sysram_resource_count;
 118
 119         disable_sr_hashing(); /* Turn off space register hashing */
 120
 121         /*
 122          * Sort the ranges. Since the number of ranges is typically
 123          * small, and performance is not an issue here, just do
 124          * a simple insertion sort.
 125          */
 126
 127         for (i = 1; i < npmem_ranges; i++) {
 128                 int j;
 129
 130                 for (j = i; j > 0; j--) {
 131                         if (pmem_ranges[j-1].start_pfn <
 132                             pmem_ranges[j].start_pfn) {
 133
 134                                 break;
 135                         }
 136                         swap(pmem_ranges[j-1], pmem_ranges[j]);
 137                 }
 138         }
 139
 140 #ifndef CONFIG_SPARSEMEM
 141         /*
 142          * Throw out ranges that are too far apart (controlled by
 143          * MAX_GAP).
 144          */
 145
 146         for (i = 1; i < npmem_ranges; i++) {
 147                 if (pmem_ranges[i].start_pfn -
 148                         (pmem_ranges[i-1].start_pfn +
 149                          pmem_ranges[i-1].pages) > MAX_GAP) {
 150                         npmem_ranges = i;
 151                         printk("Large gap in memory detected (%ld pages). "
 152                                "Consider turning on CONFIG_SPARSEMEM\n",
 153                                pmem_ranges[i].start_pfn -
 154                                (pmem_ranges[i-1].start_pfn +
 155                                 pmem_ranges[i-1].pages));
 156                         break;
 157                 }
 158         }
 159 #endif
 160
 161         /* Print the memory ranges */
 162         pr_info("Memory Ranges:\n");
 163
 164         for (i = 0; i < npmem_ranges; i++) {
 165                 struct resource *res = &sysram_resources[i];
 166                 unsigned long start;
 167                 unsigned long size;
 168
 169                 size = (pmem_ranges[i].pages << PAGE_SHIFT);
 170                 start = (pmem_ranges[i].start_pfn << PAGE_SHIFT);
 171                 pr_info("%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n",
 172                         i, start, start + (size - 1), size >> 20);
 173
 174                 /* request memory resource */
 175                 res->name = "System RAM";
 176                 res->start = start;
 177                 res->end = start + size - 1;
 178                 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 179                 request_resource(&iomem_resource, res);
 180         }
 181
 182         sysram_resource_count = npmem_ranges;
 183
 184         /*
 185          * For 32 bit kernels we limit the amount of memory we can
 186          * support, in order to preserve enough kernel address space
 187          * for other purposes. For 64 bit kernels we don't normally
 188          * limit the memory, but this mechanism can be used to
 189          * artificially limit the amount of memory (and it is written
 190          * to work with multiple memory ranges).
 191          */
 192
 193         mem_limit_func();       /* check for "mem=" argument */
 194
 195         mem_max = 0;
 196         for (i = 0; i < npmem_ranges; i++) {
 197                 unsigned long rsize;
 198
 199                 rsize = pmem_ranges[i].pages << PAGE_SHIFT;
 200                 if ((mem_max + rsize) > mem_limit) {
 201                         printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20);
 202                         if (mem_max == mem_limit)
 203                                 npmem_ranges = i;
 204                         else {
 205                                 pmem_ranges[i].pages =   (mem_limit >> PAGE_SHIFT)
 206                                                        - (mem_max >> PAGE_SHIFT);
 207                                 npmem_ranges = i + 1;
 208                                 mem_max = mem_limit;
 209                         }
 210                         break;
 211                 }
 212                 mem_max += rsize;
 213         }
 214
 215         printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20);
 216
 217 #ifndef CONFIG_SPARSEMEM
 218         /* Merge the ranges, keeping track of the holes */
 219         {
 220                 unsigned long end_pfn;
 221                 unsigned long hole_pages;
 222
 223                 npmem_holes = 0;
 224                 end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages;
 225                 for (i = 1; i < npmem_ranges; i++) {
 226
 227                         hole_pages = pmem_ranges[i].start_pfn - end_pfn;
 228                         if (hole_pages) {
 229                                 pmem_holes[npmem_holes].start_pfn = end_pfn;
 230                                 pmem_holes[npmem_holes++].pages = hole_pages;
 231                                 end_pfn += hole_pages;
 232                         }
 233                         end_pfn += pmem_ranges[i].pages;
 234                 }
 235
 236                 pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn;
 237                 npmem_ranges = 1;
 238         }
 239 #endif
 240
 241         /*
 242          * Initialize and free the full range of memory in each range.
 243          */
 244
 245         max_pfn = 0;
 246         for (i = 0; i < npmem_ranges; i++) {
 247                 unsigned long start_pfn;
 248                 unsigned long npages;
 249                 unsigned long start;
 250                 unsigned long size;
 251
 252                 start_pfn = pmem_ranges[i].start_pfn;
 253                 npages = pmem_ranges[i].pages;
 254
 255                 start = start_pfn << PAGE_SHIFT;
 256                 size = npages << PAGE_SHIFT;
 257
 258                 /* add system RAM memblock */
 259                 memblock_add(start, size);
 260
 261                 if ((start_pfn + npages) > max_pfn)
 262                         max_pfn = start_pfn + npages;
 263         }
 264
 265         /*
 266          * We can't use memblock top-down allocations because we only
 267          * created the initial mapping up to KERNEL_INITIAL_SIZE in
 268          * the assembly bootup code.
 269          */
 270         memblock_set_bottom_up(true);
 271
 272         /* IOMMU is always used to access "high mem" on those boxes
 273          * that can support enough mem that a PCI device couldn't
 274          * directly DMA to any physical addresses.
 275          * ISA DMA support will need to revisit this.
 276          */
 277         max_low_pfn = max_pfn;
 278
 279         /* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
 280
 281 #define PDC_CONSOLE_IO_IODC_SIZE 32768
 282
 283         memblock_reserve(0UL, (unsigned long)(PAGE0->mem_free +
 284                                 PDC_CONSOLE_IO_IODC_SIZE));
 285         memblock_reserve(__pa(KERNEL_BINARY_TEXT_START),
 286                         (unsigned long)(_end - KERNEL_BINARY_TEXT_START));
 287
 288 #ifndef CONFIG_SPARSEMEM
 289
 290         /* reserve the holes */
 291
 292         for (i = 0; i < npmem_holes; i++) {
 293                 memblock_reserve((pmem_holes[i].start_pfn << PAGE_SHIFT),
 294                                 (pmem_holes[i].pages << PAGE_SHIFT));
 295         }
 296 #endif
 297
 298 #ifdef CONFIG_BLK_DEV_INITRD
 299         if (initrd_start) {
 300                 printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end);
 301                 if (__pa(initrd_start) < mem_max) {
 302                         unsigned long initrd_reserve;
 303
 304                         if (__pa(initrd_end) > mem_max) {
 305                                 initrd_reserve = mem_max - __pa(initrd_start);
 306                         } else {
 307                                 initrd_reserve = initrd_end - initrd_start;
 308                         }
 309                         initrd_below_start_ok = 1;
 310                         printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
 311
 312                         memblock_reserve(__pa(initrd_start), initrd_reserve);
 313                 }
 314         }
 315 #endif
 316
 317         data_resource.start =  virt_to_phys(&data_start);
 318         data_resource.end = virt_to_phys(_end) - 1;
 319         code_resource.start = virt_to_phys(_text);
 320         code_resource.end = virt_to_phys(&data_start)-1;
 321
 322         /* We don't know which region the kernel will be in, so try
 323          * all of them.
 324          */
 325         for (i = 0; i < sysram_resource_count; i++) {
 326                 struct resource *res = &sysram_resources[i];
 327                 request_resource(res, &code_resource);
 328                 request_resource(res, &data_resource);
 329         }
 330         request_resource(&sysram_resources[0], &pdcdata_resource);
 331
 332         /* Initialize Page Deallocation Table (PDT) and check for bad memory. */
 333         pdc_pdt_init();
 334
 335         memblock_allow_resize();
 336         memblock_dump_all();
 337 }
 338
 339 static bool kernel_set_to_readonly;
 340
 341 static void __ref map_pages(unsigned long start_vaddr,
 342                             unsigned long start_paddr, unsigned long size,
 343                             pgprot_t pgprot, int force)
 344 {
 345         pmd_t *pmd;
 346         pte_t *pg_table;
 347         unsigned long end_paddr;
 348         unsigned long start_pmd;
 349         unsigned long start_pte;
 350         unsigned long tmp1;
 351         unsigned long tmp2;
 352         unsigned long address;
 353         unsigned long vaddr;
 354         unsigned long ro_start;
 355         unsigned long ro_end;
 356         unsigned long kernel_start, kernel_end;
 357
 358         ro_start = __pa((unsigned long)_text);
 359         ro_end   = __pa((unsigned long)&data_start);
 360         kernel_start = __pa((unsigned long)&__init_begin);
 361         kernel_end  = __pa((unsigned long)&_end);
 362
 363         end_paddr = start_paddr + size;
 364
 365         /* for 2-level configuration PTRS_PER_PMD is 0 so start_pmd will be 0 */
 366         start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
 367         start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
 368
 369         address = start_paddr;
 370         vaddr = start_vaddr;
 371         while (address < end_paddr) {
 372                 pgd_t *pgd = pgd_offset_k(vaddr);
 373                 p4d_t *p4d = p4d_offset(pgd, vaddr);
 374                 pud_t *pud = pud_offset(p4d, vaddr);
 375
 376 #if CONFIG_PGTABLE_LEVELS == 3
 377                 if (pud_none(*pud)) {
 378                         pmd = memblock_alloc(PAGE_SIZE << PMD_TABLE_ORDER,
 379                                              PAGE_SIZE << PMD_TABLE_ORDER);
 380                         if (!pmd)
 381                                 panic("pmd allocation failed.\n");
 382                         pud_populate(NULL, pud, pmd);
 383                 }
 384 #endif
 385
 386                 pmd = pmd_offset(pud, vaddr);
 387                 for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++, pmd++) {
 388                         if (pmd_none(*pmd)) {
 389                                 pg_table = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 390                                 if (!pg_table)
 391                                         panic("page table allocation failed\n");
 392                                 pmd_populate_kernel(NULL, pmd, pg_table);
 393                         }
 394
 395                         pg_table = pte_offset_kernel(pmd, vaddr);
 396                         for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) {
 397                                 pte_t pte;
 398                                 pgprot_t prot;
 399                                 bool huge = false;
 400
 401                                 if (force) {
 402                                         prot = pgprot;
 403                                 } else if (address < kernel_start || address >= kernel_end) {
 404                                         /* outside kernel memory */
 405                                         prot = PAGE_KERNEL;
 406                                 } else if (!kernel_set_to_readonly) {
 407                                         /* still initializing, allow writing to RO memory */
 408                                         prot = PAGE_KERNEL_RWX;
 409                                         huge = true;
 410                                 } else if (address >= ro_start) {
 411                                         /* Code (ro) and Data areas */
 412                                         prot = (address < ro_end) ?
 413                                                 PAGE_KERNEL_EXEC : PAGE_KERNEL;
 414                                         huge = true;
 415                                 } else {
 416                                         prot = PAGE_KERNEL;
 417                                 }
 418
 419                                 pte = __mk_pte(address, prot);
 420                                 if (huge)
 421                                         pte = pte_mkhuge(pte);
 422
 423                                 if (address >= end_paddr)
 424                                         break;
 425
 426                                 set_pte(pg_table, pte);
 427
 428                                 address += PAGE_SIZE;
 429                                 vaddr += PAGE_SIZE;
 430                         }
 431                         start_pte = 0;
 432
 433                         if (address >= end_paddr)
 434                             break;
 435                 }
 436                 start_pmd = 0;
 437         }
 438 }
 439
 440 void __init set_kernel_text_rw(int enable_read_write)
 441 {
 442         unsigned long start = (unsigned long) __init_begin;
 443         unsigned long end   = (unsigned long) &data_start;
 444
 445         map_pages(start, __pa(start), end-start,
 446                 PAGE_KERNEL_RWX, enable_read_write ? 1:0);
 447
 448         /* force the kernel to see the new page table entries */
 449         flush_cache_all();
 450         flush_tlb_all();
 451 }
 452
 453 void free_initmem(void)
 454 {
 455         unsigned long init_begin = (unsigned long)__init_begin;
 456         unsigned long init_end = (unsigned long)__init_end;
 457         unsigned long kernel_end  = (unsigned long)&_end;
 458
 459         /* Remap kernel text and data, but do not touch init section yet. */
 460         kernel_set_to_readonly = true;
 461         map_pages(init_end, __pa(init_end), kernel_end - init_end,
 462                   PAGE_KERNEL, 0);
 463
 464         /* The init text pages are marked R-X.  We have to
 465          * flush the icache and mark them RW-
 466          *
 467          * Do a dummy remap of the data section first (the data
 468          * section is already PAGE_KERNEL) to pull in the TLB entries
 469          * for map_kernel */
 470         map_pages(init_begin, __pa(init_begin), init_end - init_begin,
 471                   PAGE_KERNEL_RWX, 1);
 472         /* now remap at PAGE_KERNEL since the TLB is pre-primed to execute
 473          * map_pages */
 474         map_pages(init_begin, __pa(init_begin), init_end - init_begin,
 475                   PAGE_KERNEL, 1);
 476
 477         /* force the kernel to see the new TLB entries */
 478         __flush_tlb_range(0, init_begin, kernel_end);
 479
 480         /* finally dump all the instructions which were cached, since the
 481          * pages are no-longer executable */
 482         flush_icache_range(init_begin, init_end);
 483
 484         free_initmem_default(POISON_FREE_INITMEM);
 485
 486         /* set up a new led state on systems shipped LED State panel */
 487         pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
 488 }
 489
 490
 491 #ifdef CONFIG_STRICT_KERNEL_RWX
 492 void mark_rodata_ro(void)
 493 {
 494         /* rodata memory was already mapped with KERNEL_RO access rights by
 495            pagetable_init() and map_pages(). No need to do additional stuff here */
 496         unsigned long roai_size = __end_ro_after_init - __start_ro_after_init;
 497
 498         pr_info("Write protected read-only-after-init data: %luk\n", roai_size >> 10);
 499 }
 500 #endif
 501
 502
 503 /*
 504  * Just an arbitrary offset to serve as a "hole" between mapping areas
 505  * (between top of physical memory and a potential pcxl dma mapping
 506  * area, and below the vmalloc mapping area).
 507  *
 508  * The current 32K value just means that there will be a 32K "hole"
 509  * between mapping areas. That means that  any out-of-bounds memory
 510  * accesses will hopefully be caught. The vmalloc() routines leaves
 511  * a hole of 4kB between each vmalloced area for the same reason.
 512  */
 513
 514  /* Leave room for gateway page expansion */
 515 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
 516 #error KERNEL_MAP_START is in gateway reserved region
 517 #endif
 518 #define MAP_START (KERNEL_MAP_START)
 519
 520 #define VM_MAP_OFFSET  (32*1024)
 521 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
 522                                      & ~(VM_MAP_OFFSET-1)))
 523
 524 void *parisc_vmalloc_start __ro_after_init;
 525 EXPORT_SYMBOL(parisc_vmalloc_start);
 526
 527 void __init mem_init(void)
 528 {
 529         /* Do sanity checks on IPC (compat) structures */
 530         BUILD_BUG_ON(sizeof(struct ipc64_perm) != 48);
 531 #ifndef CONFIG_64BIT
 532         BUILD_BUG_ON(sizeof(struct semid64_ds) != 80);
 533         BUILD_BUG_ON(sizeof(struct msqid64_ds) != 104);
 534         BUILD_BUG_ON(sizeof(struct shmid64_ds) != 104);
 535 #endif
 536 #ifdef CONFIG_COMPAT
 537         BUILD_BUG_ON(sizeof(struct compat_ipc64_perm) != sizeof(struct ipc64_perm));
 538         BUILD_BUG_ON(sizeof(struct compat_semid64_ds) != 80);
 539         BUILD_BUG_ON(sizeof(struct compat_msqid64_ds) != 104);
 540         BUILD_BUG_ON(sizeof(struct compat_shmid64_ds) != 104);
 541 #endif
 542
 543         /* Do sanity checks on page table constants */
 544         BUILD_BUG_ON(PTE_ENTRY_SIZE != sizeof(pte_t));
 545         BUILD_BUG_ON(PMD_ENTRY_SIZE != sizeof(pmd_t));
 546         BUILD_BUG_ON(PGD_ENTRY_SIZE != sizeof(pgd_t));
 547         BUILD_BUG_ON(PAGE_SHIFT + BITS_PER_PTE + BITS_PER_PMD + BITS_PER_PGD
 548                         > BITS_PER_LONG);
 549 #if CONFIG_PGTABLE_LEVELS == 3
 550         BUILD_BUG_ON(PT_INITIAL > PTRS_PER_PMD);
 551 #else
 552         BUILD_BUG_ON(PT_INITIAL > PTRS_PER_PGD);
 553 #endif
 554
 555 #ifdef CONFIG_64BIT
 556         /* avoid ldil_%L() asm statements to sign-extend into upper 32-bits */
 557         BUILD_BUG_ON(__PAGE_OFFSET >= 0x80000000);
 558         BUILD_BUG_ON(TMPALIAS_MAP_START >= 0x80000000);
 559 #endif
 560
 561         high_memory = __va((max_pfn << PAGE_SHIFT));
 562         set_max_mapnr(max_low_pfn);
 563         memblock_free_all();
 564
 565 #ifdef CONFIG_PA11
 566         if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) {
 567                 pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
 568                 parisc_vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start
 569                                                 + PCXL_DMA_MAP_SIZE);
 570         } else
 571 #endif
 572                 parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START);
 573
 574 #if 0
 575         /*
 576          * Do not expose the virtual kernel memory layout to userspace.
 577          * But keep code for debugging purposes.
 578          */
 579         printk("virtual kernel memory layout:\n"
 580                "     vmalloc : 0x%px - 0x%px   (%4ld MB)\n"
 581                "     fixmap  : 0x%px - 0x%px   (%4ld kB)\n"
 582                "     memory  : 0x%px - 0x%px   (%4ld MB)\n"
 583                "       .init : 0x%px - 0x%px   (%4ld kB)\n"
 584                "       .data : 0x%px - 0x%px   (%4ld kB)\n"
 585                "       .text : 0x%px - 0x%px   (%4ld kB)\n",
 586
 587                (void*)VMALLOC_START, (void*)VMALLOC_END,
 588                (VMALLOC_END - VMALLOC_START) >> 20,
 589
 590                (void *)FIXMAP_START, (void *)(FIXMAP_START + FIXMAP_SIZE),
 591                (unsigned long)(FIXMAP_SIZE / 1024),
 592
 593                __va(0), high_memory,
 594                ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,
 595
 596                __init_begin, __init_end,
 597                ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10,
 598
 599                _etext, _edata,
 600                ((unsigned long)_edata - (unsigned long)_etext) >> 10,
 601
 602                _text, _etext,
 603                ((unsigned long)_etext - (unsigned long)_text) >> 10);
 604 #endif
 605 }
 606
 607 unsigned long *empty_zero_page __ro_after_init;
 608 EXPORT_SYMBOL(empty_zero_page);
 609
 610 /*
 611  * pagetable_init() sets up the page tables
 612  *
 613  * Note that gateway_init() places the Linux gateway page at page 0.
 614  * Since gateway pages cannot be dereferenced this has the desirable
 615  * side effect of trapping those pesky NULL-reference errors in the
 616  * kernel.
 617  */
 618 static void __init pagetable_init(void)
 619 {
 620         int range;
 621
 622         /* Map each physical memory range to its kernel vaddr */
 623
 624         for (range = 0; range < npmem_ranges; range++) {
 625                 unsigned long start_paddr;
 626                 unsigned long size;
 627
 628                 start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
 629                 size = pmem_ranges[range].pages << PAGE_SHIFT;
 630
 631                 map_pages((unsigned long)__va(start_paddr), start_paddr,
 632                           size, PAGE_KERNEL, 0);
 633         }
 634
 635 #ifdef CONFIG_BLK_DEV_INITRD
 636         if (initrd_end && initrd_end > mem_limit) {
 637                 printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
 638                 map_pages(initrd_start, __pa(initrd_start),
 639                           initrd_end - initrd_start, PAGE_KERNEL, 0);
 640         }
 641 #endif
 642
 643         empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 644         if (!empty_zero_page)
 645                 panic("zero page allocation failed.\n");
 646
 647 }
 648
 649 static void __init gateway_init(void)
 650 {
 651         unsigned long linux_gateway_page_addr;
 652         /* FIXME: This is 'const' in order to trick the compiler
 653            into not treating it as DP-relative data. */
 654         extern void * const linux_gateway_page;
 655
 656         linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
 657
 658         /*
 659          * Setup Linux Gateway page.
 660          *
 661          * The Linux gateway page will reside in kernel space (on virtual
 662          * page 0), so it doesn't need to be aliased into user space.
 663          */
 664
 665         map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
 666                   PAGE_SIZE, PAGE_GATEWAY, 1);
 667 }
 668
 669 static void __init fixmap_init(void)
 670 {
 671         unsigned long addr = FIXMAP_START;
 672         unsigned long end = FIXMAP_START + FIXMAP_SIZE;
 673         pgd_t *pgd = pgd_offset_k(addr);
 674         p4d_t *p4d = p4d_offset(pgd, addr);
 675         pud_t *pud = pud_offset(p4d, addr);
 676         pmd_t *pmd;
 677
 678         BUILD_BUG_ON(FIXMAP_SIZE > PMD_SIZE);
 679
 680 #if CONFIG_PGTABLE_LEVELS == 3
 681         if (pud_none(*pud)) {
 682                 pmd = memblock_alloc(PAGE_SIZE << PMD_TABLE_ORDER,
 683                                      PAGE_SIZE << PMD_TABLE_ORDER);
 684                 if (!pmd)
 685                         panic("fixmap: pmd allocation failed.\n");
 686                 pud_populate(NULL, pud, pmd);
 687         }
 688 #endif
 689
 690         pmd = pmd_offset(pud, addr);
 691         do {
 692                 pte_t *pte = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 693                 if (!pte)
 694                         panic("fixmap: pte allocation failed.\n");
 695
 696                 pmd_populate_kernel(&init_mm, pmd, pte);
 697
 698                 addr += PAGE_SIZE;
 699         } while (addr < end);
 700 }
 701
 702 static void __init parisc_bootmem_free(void)
 703 {
 704         unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, };
 705
 706         max_zone_pfn[0] = memblock_end_of_DRAM();
 707
 708         free_area_init(max_zone_pfn);
 709 }
 710
 711 void __init paging_init(void)
 712 {
 713         setup_bootmem();
 714         pagetable_init();
 715         gateway_init();
 716         fixmap_init();
 717         flush_cache_all_local(); /* start with known state */
 718         flush_tlb_all_local(NULL);
 719
 720         sparse_init();
 721         parisc_bootmem_free();
 722 }
 723
 724 static void alloc_btlb(unsigned long start, unsigned long end, int *slot,
 725                         unsigned long entry_info)
 726 {
 727         const int slot_max = btlb_info.fixed_range_info.num_comb;
 728         int min_num_pages = btlb_info.min_size;
 729         unsigned long size;
 730
 731         /* map at minimum 4 pages */
 732         if (min_num_pages < 4)
 733                 min_num_pages = 4;
 734
 735         size = HUGEPAGE_SIZE;
 736         while (start < end && *slot < slot_max && size >= PAGE_SIZE) {
 737                 /* starting address must have same alignment as size! */
 738                 /* if correctly aligned and fits in double size, increase */
 739                 if (((start & (2 * size - 1)) == 0) &&
 740                     (end - start) >= (2 * size)) {
 741                         size <<= 1;
 742                         continue;
 743                 }
 744                 /* if current size alignment is too big, try smaller size */
 745                 if ((start & (size - 1)) != 0) {
 746                         size >>= 1;
 747                         continue;
 748                 }
 749                 if ((end - start) >= size) {
 750                         if ((size >> PAGE_SHIFT) >= min_num_pages)
 751                                 pdc_btlb_insert(start >> PAGE_SHIFT, __pa(start) >> PAGE_SHIFT,
 752                                         size >> PAGE_SHIFT, entry_info, *slot);
 753                         (*slot)++;
 754                         start += size;
 755                         continue;
 756                 }
 757                 size /= 2;
 758                 continue;
 759         }
 760 }
 761
 762 void btlb_init_per_cpu(void)
 763 {
 764         unsigned long s, t, e;
 765         int slot;
 766
 767         /* BTLBs are not available on 64-bit CPUs */
 768         if (IS_ENABLED(CONFIG_PA20))
 769                 return;
 770         else if (pdc_btlb_info(&btlb_info) < 0) {
 771                 memset(&btlb_info, 0, sizeof btlb_info);
 772         }
 773
 774         /* insert BLTLBs for code and data segments */
 775         s = (uintptr_t) dereference_function_descriptor(&_stext);
 776         e = (uintptr_t) dereference_function_descriptor(&_etext);
 777         t = (uintptr_t) dereference_function_descriptor(&_sdata);
 778         BUG_ON(t != e);
 779
 780         /* code segments */
 781         slot = 0;
 782         alloc_btlb(s, e, &slot, 0x13800000);
 783
 784         /* sanity check */
 785         t = (uintptr_t) dereference_function_descriptor(&_edata);
 786         e = (uintptr_t) dereference_function_descriptor(&__bss_start);
 787         BUG_ON(t != e);
 788
 789         /* data segments */
 790         s = (uintptr_t) dereference_function_descriptor(&_sdata);
 791         e = (uintptr_t) dereference_function_descriptor(&__bss_stop);
 792         alloc_btlb(s, e, &slot, 0x11800000);
 793 }
 794
 795 #ifdef CONFIG_PA20
 796
 797 /*
 798  * Currently, all PA20 chips have 18 bit protection IDs, which is the
 799  * limiting factor (space ids are 32 bits).
 800  */
 801
 802 #define NR_SPACE_IDS 262144
 803
 804 #else
 805
 806 /*
 807  * Currently we have a one-to-one relationship between space IDs and
 808  * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
 809  * support 15 bit protection IDs, so that is the limiting factor.
 810  * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's
 811  * probably not worth the effort for a special case here.
 812  */
 813
 814 #define NR_SPACE_IDS 32768
 815
 816 #endif  /* !CONFIG_PA20 */
 817
 818 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
 819 #define SID_ARRAY_SIZE  (NR_SPACE_IDS / (8 * sizeof(long)))
 820
 821 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
 822 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
 823 static unsigned long space_id_index;
 824 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
 825 static unsigned long dirty_space_ids;
 826
 827 static DEFINE_SPINLOCK(sid_lock);
 828
 829 unsigned long alloc_sid(void)
 830 {
 831         unsigned long index;
 832
 833         spin_lock(&sid_lock);
 834
 835         if (free_space_ids == 0) {
 836                 if (dirty_space_ids != 0) {
 837                         spin_unlock(&sid_lock);
 838                         flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
 839                         spin_lock(&sid_lock);
 840                 }
 841                 BUG_ON(free_space_ids == 0);
 842         }
 843
 844         free_space_ids--;
 845
 846         index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
 847         space_id[BIT_WORD(index)] |= BIT_MASK(index);
 848         space_id_index = index;
 849
 850         spin_unlock(&sid_lock);
 851
 852         return index << SPACEID_SHIFT;
 853 }
 854
 855 void free_sid(unsigned long spaceid)
 856 {
 857         unsigned long index = spaceid >> SPACEID_SHIFT;
 858         unsigned long *dirty_space_offset, mask;
 859
 860         dirty_space_offset = &dirty_space_id[BIT_WORD(index)];
 861         mask = BIT_MASK(index);
 862
 863         spin_lock(&sid_lock);
 864
 865         BUG_ON(*dirty_space_offset & mask); /* attempt to free space id twice */
 866
 867         *dirty_space_offset |= mask;
 868         dirty_space_ids++;
 869
 870         spin_unlock(&sid_lock);
 871 }
 872
 873
 874 #ifdef CONFIG_SMP
 875 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
 876 {
 877         int i;
 878
 879         /* NOTE: sid_lock must be held upon entry */
 880
 881         *ndirtyptr = dirty_space_ids;
 882         if (dirty_space_ids != 0) {
 883             for (i = 0; i < SID_ARRAY_SIZE; i++) {
 884                 dirty_array[i] = dirty_space_id[i];
 885                 dirty_space_id[i] = 0;
 886             }
 887             dirty_space_ids = 0;
 888         }
 889
 890         return;
 891 }
 892
 893 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
 894 {
 895         int i;
 896
 897         /* NOTE: sid_lock must be held upon entry */
 898
 899         if (ndirty != 0) {
 900                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
 901                         space_id[i] ^= dirty_array[i];
 902                 }
 903
 904                 free_space_ids += ndirty;
 905                 space_id_index = 0;
 906         }
 907 }
 908
 909 #else /* CONFIG_SMP */
 910
 911 static void recycle_sids(void)
 912 {
 913         int i;
 914
 915         /* NOTE: sid_lock must be held upon entry */
 916
 917         if (dirty_space_ids != 0) {
 918                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
 919                         space_id[i] ^= dirty_space_id[i];
 920                         dirty_space_id[i] = 0;
 921                 }
 922
 923                 free_space_ids += dirty_space_ids;
 924                 dirty_space_ids = 0;
 925                 space_id_index = 0;
 926         }
 927 }
 928 #endif
 929
 930 /*
 931  * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
 932  * purged, we can safely reuse the space ids that were released but
 933  * not flushed from the tlb.
 934  */
 935
 936 #ifdef CONFIG_SMP
 937
 938 static unsigned long recycle_ndirty;
 939 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
 940 static unsigned int recycle_inuse;
 941
 942 void flush_tlb_all(void)
 943 {
 944         int do_recycle;
 945
 946         do_recycle = 0;
 947         spin_lock(&sid_lock);
 948         __inc_irq_stat(irq_tlb_count);
 949         if (dirty_space_ids > RECYCLE_THRESHOLD) {
 950             BUG_ON(recycle_inuse);  /* FIXME: Use a semaphore/wait queue here */
 951             get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
 952             recycle_inuse++;
 953             do_recycle++;
 954         }
 955         spin_unlock(&sid_lock);
 956         on_each_cpu(flush_tlb_all_local, NULL, 1);
 957         if (do_recycle) {
 958             spin_lock(&sid_lock);
 959             recycle_sids(recycle_ndirty,recycle_dirty_array);
 960             recycle_inuse = 0;
 961             spin_unlock(&sid_lock);
 962         }
 963 }
 964 #else
 965 void flush_tlb_all(void)
 966 {
 967         spin_lock(&sid_lock);
 968         __inc_irq_stat(irq_tlb_count);
 969         flush_tlb_all_local(NULL);
 970         recycle_sids();
 971         spin_unlock(&sid_lock);
 972 }
 973 #endif
 974
 975 static const pgprot_t protection_map[16] = {
 976         [VM_NONE]                                       = PAGE_NONE,
 977         [VM_READ]                                       = PAGE_READONLY,
 978         [VM_WRITE]                                      = PAGE_NONE,
 979         [VM_WRITE | VM_READ]                            = PAGE_READONLY,
 980         [VM_EXEC]                                       = PAGE_EXECREAD,
 981         [VM_EXEC | VM_READ]                             = PAGE_EXECREAD,
 982         [VM_EXEC | VM_WRITE]                            = PAGE_EXECREAD,
 983         [VM_EXEC | VM_WRITE | VM_READ]                  = PAGE_EXECREAD,
 984         [VM_SHARED]                                     = PAGE_NONE,
 985         [VM_SHARED | VM_READ]                           = PAGE_READONLY,
 986         [VM_SHARED | VM_WRITE]                          = PAGE_WRITEONLY,
 987         [VM_SHARED | VM_WRITE | VM_READ]                = PAGE_SHARED,
 988         [VM_SHARED | VM_EXEC]                           = PAGE_EXECREAD,
 989         [VM_SHARED | VM_EXEC | VM_READ]                 = PAGE_EXECREAD,
 990         [VM_SHARED | VM_EXEC | VM_WRITE]                = PAGE_RWX,
 991         [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]      = PAGE_RWX
 992 };
 993 DECLARE_VM_GET_PAGE_PROT