arch/arm/mm/init.c

   1 /*
   2  *  linux/arch/arm/mm/init.c
   3  *
   4  *  Copyright (C) 1995-2005 Russell King
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10 #include <linux/kernel.h>
  11 #include <linux/errno.h>
  12 #include <linux/swap.h>
  13 #include <linux/init.h>
  14 #include <linux/bootmem.h>
  15 #include <linux/mman.h>
  16 #include <linux/export.h>
  17 #include <linux/nodemask.h>
  18 #include <linux/initrd.h>
  19 #include <linux/of_fdt.h>
  20 #include <linux/highmem.h>
  21 #include <linux/gfp.h>
  22 #include <linux/memblock.h>
  23 #include <linux/dma-contiguous.h>
  24 #include <linux/sizes.h>
  25
  26 #include <asm/cp15.h>
  27 #include <asm/mach-types.h>
  28 #include <asm/memblock.h>
  29 #include <asm/prom.h>
  30 #include <asm/sections.h>
  31 #include <asm/setup.h>
  32 #include <asm/system_info.h>
  33 #include <asm/tlb.h>
  34 #include <asm/fixmap.h>
  35
  36 #include <asm/mach/arch.h>
  37 #include <asm/mach/map.h>
  38
  39 #include "mm.h"
  40
  41 #ifdef CONFIG_CPU_CP15_MMU
  42 unsigned long __init __clear_cr(unsigned long mask)
  43 {
  44         cr_alignment = cr_alignment & ~mask;
  45         return cr_alignment;
  46 }
  47 #endif
  48
  49 static phys_addr_t phys_initrd_start __initdata = 0;
  50 static unsigned long phys_initrd_size __initdata = 0;
  51
  52 static int __init early_initrd(char *p)
  53 {
  54         phys_addr_t start;
  55         unsigned long size;
  56         char *endp;
  57
  58         start = memparse(p, &endp);
  59         if (*endp == ',') {
  60                 size = memparse(endp + 1, NULL);
  61
  62                 phys_initrd_start = start;
  63                 phys_initrd_size = size;
  64         }
  65         return 0;
  66 }
  67 early_param("initrd", early_initrd);
  68
  69 static int __init parse_tag_initrd(const struct tag *tag)
  70 {
  71         pr_warn("ATAG_INITRD is deprecated; "
  72                 "please update your bootloader.\n");
  73         phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
  74         phys_initrd_size = tag->u.initrd.size;
  75         return 0;
  76 }
  77
  78 __tagtable(ATAG_INITRD, parse_tag_initrd);
  79
  80 static int __init parse_tag_initrd2(const struct tag *tag)
  81 {
  82         phys_initrd_start = tag->u.initrd.start;
  83         phys_initrd_size = tag->u.initrd.size;
  84         return 0;
  85 }
  86
  87 __tagtable(ATAG_INITRD2, parse_tag_initrd2);
  88
  89 static void __init find_limits(unsigned long *min, unsigned long *max_low,
  90                                unsigned long *max_high)
  91 {
  92         *max_low = PFN_DOWN(memblock_get_current_limit());
  93         *min = PFN_UP(memblock_start_of_DRAM());
  94         *max_high = PFN_DOWN(memblock_end_of_DRAM());
  95 }
  96
  97 #ifdef CONFIG_ZONE_DMA
  98
  99 phys_addr_t arm_dma_zone_size __read_mostly;
 100 EXPORT_SYMBOL(arm_dma_zone_size);
 101
 102 /*
 103  * The DMA mask corresponding to the maximum bus address allocatable
 104  * using GFP_DMA.  The default here places no restriction on DMA
 105  * allocations.  This must be the smallest DMA mask in the system,
 106  * so a successful GFP_DMA allocation will always satisfy this.
 107  */
 108 phys_addr_t arm_dma_limit;
 109 unsigned long arm_dma_pfn_limit;
 110
 111 static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
 112         unsigned long dma_size)
 113 {
 114         if (size[0] <= dma_size)
 115                 return;
 116
 117         size[ZONE_NORMAL] = size[0] - dma_size;
 118         size[ZONE_DMA] = dma_size;
 119         hole[ZONE_NORMAL] = hole[0];
 120         hole[ZONE_DMA] = 0;
 121 }
 122 #endif
 123
 124 void __init setup_dma_zone(const struct machine_desc *mdesc)
 125 {
 126 #ifdef CONFIG_ZONE_DMA
 127         if (mdesc->dma_zone_size) {
 128                 arm_dma_zone_size = mdesc->dma_zone_size;
 129                 arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
 130         } else
 131                 arm_dma_limit = 0xffffffff;
 132         arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT;
 133 #endif
 134 }
 135
 136 static void __init zone_sizes_init(unsigned long min, unsigned long max_low,
 137         unsigned long max_high)
 138 {
 139         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
 140         struct memblock_region *reg;
 141
 142         /*
 143          * initialise the zones.
 144          */
 145         memset(zone_size, 0, sizeof(zone_size));
 146
 147         /*
 148          * The memory size has already been determined.  If we need
 149          * to do anything fancy with the allocation of this memory
 150          * to the zones, now is the time to do it.
 151          */
 152         zone_size[0] = max_low - min;
 153 #ifdef CONFIG_HIGHMEM
 154         zone_size[ZONE_HIGHMEM] = max_high - max_low;
 155 #endif
 156
 157         /*
 158          * Calculate the size of the holes.
 159          *  holes = node_size - sum(bank_sizes)
 160          */
 161         memcpy(zhole_size, zone_size, sizeof(zhole_size));
 162         for_each_memblock(memory, reg) {
 163                 unsigned long start = memblock_region_memory_base_pfn(reg);
 164                 unsigned long end = memblock_region_memory_end_pfn(reg);
 165
 166                 if (start < max_low) {
 167                         unsigned long low_end = min(end, max_low);
 168                         zhole_size[0] -= low_end - start;
 169                 }
 170 #ifdef CONFIG_HIGHMEM
 171                 if (end > max_low) {
 172                         unsigned long high_start = max(start, max_low);
 173                         zhole_size[ZONE_HIGHMEM] -= end - high_start;
 174                 }
 175 #endif
 176         }
 177
 178 #ifdef CONFIG_ZONE_DMA
 179         /*
 180          * Adjust the sizes according to any special requirements for
 181          * this machine type.
 182          */
 183         if (arm_dma_zone_size)
 184                 arm_adjust_dma_zone(zone_size, zhole_size,
 185                         arm_dma_zone_size >> PAGE_SHIFT);
 186 #endif
 187
 188         free_area_init_node(0, zone_size, min, zhole_size);
 189 }
 190
 191 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
 192 int pfn_valid(unsigned long pfn)
 193 {
 194         return memblock_is_memory(__pfn_to_phys(pfn));
 195 }
 196 EXPORT_SYMBOL(pfn_valid);
 197 #endif
 198
 199 #ifndef CONFIG_SPARSEMEM
 200 static void __init arm_memory_present(void)
 201 {
 202 }
 203 #else
 204 static void __init arm_memory_present(void)
 205 {
 206         struct memblock_region *reg;
 207
 208         for_each_memblock(memory, reg)
 209                 memory_present(0, memblock_region_memory_base_pfn(reg),
 210                                memblock_region_memory_end_pfn(reg));
 211 }
 212 #endif
 213
 214 static bool arm_memblock_steal_permitted = true;
 215
 216 phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align)
 217 {
 218         phys_addr_t phys;
 219
 220         BUG_ON(!arm_memblock_steal_permitted);
 221
 222         phys = memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE);
 223         memblock_free(phys, size);
 224         memblock_remove(phys, size);
 225
 226         return phys;
 227 }
 228
 229 void __init arm_memblock_init(const struct machine_desc *mdesc)
 230 {
 231         /* Register the kernel text, kernel data and initrd with memblock. */
 232 #ifdef CONFIG_XIP_KERNEL
 233         memblock_reserve(__pa(_sdata), _end - _sdata);
 234 #else
 235         memblock_reserve(__pa(_stext), _end - _stext);
 236 #endif
 237 #ifdef CONFIG_BLK_DEV_INITRD
 238         /* FDT scan will populate initrd_start */
 239         if (initrd_start && !phys_initrd_size) {
 240                 phys_initrd_start = __virt_to_phys(initrd_start);
 241                 phys_initrd_size = initrd_end - initrd_start;
 242         }
 243         initrd_start = initrd_end = 0;
 244         if (phys_initrd_size &&
 245             !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) {
 246                 pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n",
 247                        (u64)phys_initrd_start, phys_initrd_size);
 248                 phys_initrd_start = phys_initrd_size = 0;
 249         }
 250         if (phys_initrd_size &&
 251             memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
 252                 pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region - disabling initrd\n",
 253                        (u64)phys_initrd_start, phys_initrd_size);
 254                 phys_initrd_start = phys_initrd_size = 0;
 255         }
 256         if (phys_initrd_size) {
 257                 memblock_reserve(phys_initrd_start, phys_initrd_size);
 258
 259                 /* Now convert initrd to virtual addresses */
 260                 initrd_start = __phys_to_virt(phys_initrd_start);
 261                 initrd_end = initrd_start + phys_initrd_size;
 262         }
 263 #endif
 264
 265         arm_mm_memblock_reserve();
 266
 267         /* reserve any platform specific memblock areas */
 268         if (mdesc->reserve)
 269                 mdesc->reserve();
 270
 271         early_init_fdt_reserve_self();
 272         early_init_fdt_scan_reserved_mem();
 273
 274         /* reserve memory for DMA contiguous allocations */
 275         dma_contiguous_reserve(arm_dma_limit);
 276
 277         arm_memblock_steal_permitted = false;
 278         memblock_dump_all();
 279 }
 280
 281 void __init bootmem_init(void)
 282 {
 283         unsigned long min, max_low, max_high;
 284
 285         memblock_allow_resize();
 286         max_low = max_high = 0;
 287
 288         find_limits(&min, &max_low, &max_high);
 289
 290         early_memtest((phys_addr_t)min << PAGE_SHIFT,
 291                       (phys_addr_t)max_low << PAGE_SHIFT);
 292
 293         /*
 294          * Sparsemem tries to allocate bootmem in memory_present(),
 295          * so must be done after the fixed reservations
 296          */
 297         arm_memory_present();
 298
 299         /*
 300          * sparse_init() needs the bootmem allocator up and running.
 301          */
 302         sparse_init();
 303
 304         /*
 305          * Now free the memory - free_area_init_node needs
 306          * the sparse mem_map arrays initialized by sparse_init()
 307          * for memmap_init_zone(), otherwise all PFNs are invalid.
 308          */
 309         zone_sizes_init(min, max_low, max_high);
 310
 311         /*
 312          * This doesn't seem to be used by the Linux memory manager any
 313          * more, but is used by ll_rw_block.  If we can get rid of it, we
 314          * also get rid of some of the stuff above as well.
 315          */
 316         min_low_pfn = min;
 317         max_low_pfn = max_low;
 318         max_pfn = max_high;
 319 }
 320
 321 /*
 322  * Poison init memory with an undefined instruction (ARM) or a branch to an
 323  * undefined instruction (Thumb).
 324  */
 325 static inline void poison_init_mem(void *s, size_t count)
 326 {
 327         u32 *p = (u32 *)s;
 328         for (; count != 0; count -= 4)
 329                 *p++ = 0xe7fddef0;
 330 }
 331
 332 static inline void
 333 free_memmap(unsigned long start_pfn, unsigned long end_pfn)
 334 {
 335         struct page *start_pg, *end_pg;
 336         phys_addr_t pg, pgend;
 337
 338         /*
 339          * Convert start_pfn/end_pfn to a struct page pointer.
 340          */
 341         start_pg = pfn_to_page(start_pfn - 1) + 1;
 342         end_pg = pfn_to_page(end_pfn - 1) + 1;
 343
 344         /*
 345          * Convert to physical addresses, and
 346          * round start upwards and end downwards.
 347          */
 348         pg = PAGE_ALIGN(__pa(start_pg));
 349         pgend = __pa(end_pg) & PAGE_MASK;
 350
 351         /*
 352          * If there are free pages between these,
 353          * free the section of the memmap array.
 354          */
 355         if (pg < pgend)
 356                 memblock_free_early(pg, pgend - pg);
 357 }
 358
 359 /*
 360  * The mem_map array can get very big.  Free the unused area of the memory map.
 361  */
 362 static void __init free_unused_memmap(void)
 363 {
 364         unsigned long start, prev_end = 0;
 365         struct memblock_region *reg;
 366
 367         /*
 368          * This relies on each bank being in address order.
 369          * The banks are sorted previously in bootmem_init().
 370          */
 371         for_each_memblock(memory, reg) {
 372                 start = memblock_region_memory_base_pfn(reg);
 373
 374 #ifdef CONFIG_SPARSEMEM
 375                 /*
 376                  * Take care not to free memmap entries that don't exist
 377                  * due to SPARSEMEM sections which aren't present.
 378                  */
 379                 start = min(start,
 380                                  ALIGN(prev_end, PAGES_PER_SECTION));
 381 #else
 382                 /*
 383                  * Align down here since the VM subsystem insists that the
 384                  * memmap entries are valid from the bank start aligned to
 385                  * MAX_ORDER_NR_PAGES.
 386                  */
 387                 start = round_down(start, MAX_ORDER_NR_PAGES);
 388 #endif
 389                 /*
 390                  * If we had a previous bank, and there is a space
 391                  * between the current bank and the previous, free it.
 392                  */
 393                 if (prev_end && prev_end < start)
 394                         free_memmap(prev_end, start);
 395
 396                 /*
 397                  * Align up here since the VM subsystem insists that the
 398                  * memmap entries are valid from the bank end aligned to
 399                  * MAX_ORDER_NR_PAGES.
 400                  */
 401                 prev_end = ALIGN(memblock_region_memory_end_pfn(reg),
 402                                  MAX_ORDER_NR_PAGES);
 403         }
 404
 405 #ifdef CONFIG_SPARSEMEM
 406         if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
 407                 free_memmap(prev_end,
 408                             ALIGN(prev_end, PAGES_PER_SECTION));
 409 #endif
 410 }
 411
 412 #ifdef CONFIG_HIGHMEM
 413 static inline void free_area_high(unsigned long pfn, unsigned long end)
 414 {
 415         for (; pfn < end; pfn++)
 416                 free_highmem_page(pfn_to_page(pfn));
 417 }
 418 #endif
 419
 420 static void __init free_highpages(void)
 421 {
 422 #ifdef CONFIG_HIGHMEM
 423         unsigned long max_low = max_low_pfn;
 424         struct memblock_region *mem, *res;
 425
 426         /* set highmem page free */
 427         for_each_memblock(memory, mem) {
 428                 unsigned long start = memblock_region_memory_base_pfn(mem);
 429                 unsigned long end = memblock_region_memory_end_pfn(mem);
 430
 431                 /* Ignore complete lowmem entries */
 432                 if (end <= max_low)
 433                         continue;
 434
 435                 /* Truncate partial highmem entries */
 436                 if (start < max_low)
 437                         start = max_low;
 438
 439                 /* Find and exclude any reserved regions */
 440                 for_each_memblock(reserved, res) {
 441                         unsigned long res_start, res_end;
 442
 443                         res_start = memblock_region_reserved_base_pfn(res);
 444                         res_end = memblock_region_reserved_end_pfn(res);
 445
 446                         if (res_end < start)
 447                                 continue;
 448                         if (res_start < start)
 449                                 res_start = start;
 450                         if (res_start > end)
 451                                 res_start = end;
 452                         if (res_end > end)
 453                                 res_end = end;
 454                         if (res_start != start)
 455                                 free_area_high(start, res_start);
 456                         start = res_end;
 457                         if (start == end)
 458                                 break;
 459                 }
 460
 461                 /* And now free anything which remains */
 462                 if (start < end)
 463                         free_area_high(start, end);
 464         }
 465 #endif
 466 }
 467
 468 /*
 469  * mem_init() marks the free areas in the mem_map and tells us how much
 470  * memory is free.  This is done after various parts of the system have
 471  * claimed their memory after the kernel image.
 472  */
 473 void __init mem_init(void)
 474 {
 475 #ifdef CONFIG_HAVE_TCM
 476         /* These pointers are filled in on TCM detection */
 477         extern u32 dtcm_end;
 478         extern u32 itcm_end;
 479 #endif
 480
 481         set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
 482
 483         /* this will put all unused low memory onto the freelists */
 484         free_unused_memmap();
 485         free_all_bootmem();
 486
 487 #ifdef CONFIG_SA1111
 488         /* now that our DMA memory is actually so designated, we can free it */
 489         free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL);
 490 #endif
 491
 492         free_highpages();
 493
 494         mem_init_print_info(NULL);
 495
 496 #define MLK(b, t) b, t, ((t) - (b)) >> 10
 497 #define MLM(b, t) b, t, ((t) - (b)) >> 20
 498 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
 499
 500         pr_notice("Virtual kernel memory layout:\n"
 501                         "    vector  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 502 #ifdef CONFIG_HAVE_TCM
 503                         "    DTCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 504                         "    ITCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 505 #endif
 506                         "    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 507                         "    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 508                         "    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 509 #ifdef CONFIG_HIGHMEM
 510                         "    pkmap   : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 511 #endif
 512 #ifdef CONFIG_MODULES
 513                         "    modules : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 514 #endif
 515                         "      .text : 0x%p" " - 0x%p" "   (%4td kB)\n"
 516                         "      .init : 0x%p" " - 0x%p" "   (%4td kB)\n"
 517                         "      .data : 0x%p" " - 0x%p" "   (%4td kB)\n"
 518                         "       .bss : 0x%p" " - 0x%p" "   (%4td kB)\n",
 519
 520                         MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
 521                                 (PAGE_SIZE)),
 522 #ifdef CONFIG_HAVE_TCM
 523                         MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
 524                         MLK(ITCM_OFFSET, (unsigned long) itcm_end),
 525 #endif
 526                         MLK(FIXADDR_START, FIXADDR_END),
 527                         MLM(VMALLOC_START, VMALLOC_END),
 528                         MLM(PAGE_OFFSET, (unsigned long)high_memory),
 529 #ifdef CONFIG_HIGHMEM
 530                         MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
 531                                 (PAGE_SIZE)),
 532 #endif
 533 #ifdef CONFIG_MODULES
 534                         MLM(MODULES_VADDR, MODULES_END),
 535 #endif
 536
 537                         MLK_ROUNDUP(_text, _etext),
 538                         MLK_ROUNDUP(__init_begin, __init_end),
 539                         MLK_ROUNDUP(_sdata, _edata),
 540                         MLK_ROUNDUP(__bss_start, __bss_stop));
 541
 542 #undef MLK
 543 #undef MLM
 544 #undef MLK_ROUNDUP
 545
 546         /*
 547          * Check boundaries twice: Some fundamental inconsistencies can
 548          * be detected at build time already.
 549          */
 550 #ifdef CONFIG_MMU
 551         BUILD_BUG_ON(TASK_SIZE                          > MODULES_VADDR);
 552         BUG_ON(TASK_SIZE                                > MODULES_VADDR);
 553 #endif
 554
 555 #ifdef CONFIG_HIGHMEM
 556         BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
 557         BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE      > PAGE_OFFSET);
 558 #endif
 559
 560         if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
 561                 extern int sysctl_overcommit_memory;
 562                 /*
 563                  * On a machine this small we won't get
 564                  * anywhere without overcommit, so turn
 565                  * it on by default.
 566                  */
 567                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 568         }
 569 }
 570
 571 #ifdef CONFIG_ARM_KERNMEM_PERMS
 572 struct section_perm {
 573         unsigned long start;
 574         unsigned long end;
 575         pmdval_t mask;
 576         pmdval_t prot;
 577         pmdval_t clear;
 578 };
 579
 580 static struct section_perm nx_perms[] = {
 581         /* Make pages tables, etc before _stext RW (set NX). */
 582         {
 583                 .start  = PAGE_OFFSET,
 584                 .end    = (unsigned long)_stext,
 585                 .mask   = ~PMD_SECT_XN,
 586                 .prot   = PMD_SECT_XN,
 587         },
 588         /* Make init RW (set NX). */
 589         {
 590                 .start  = (unsigned long)__init_begin,
 591                 .end    = (unsigned long)_sdata,
 592                 .mask   = ~PMD_SECT_XN,
 593                 .prot   = PMD_SECT_XN,
 594         },
 595 #ifdef CONFIG_DEBUG_RODATA
 596         /* Make rodata NX (set RO in ro_perms below). */
 597         {
 598                 .start  = (unsigned long)__start_rodata,
 599                 .end    = (unsigned long)__init_begin,
 600                 .mask   = ~PMD_SECT_XN,
 601                 .prot   = PMD_SECT_XN,
 602         },
 603 #endif
 604 };
 605
 606 #ifdef CONFIG_DEBUG_RODATA
 607 static struct section_perm ro_perms[] = {
 608         /* Make kernel code and rodata RX (set RO). */
 609         {
 610                 .start  = (unsigned long)_stext,
 611                 .end    = (unsigned long)__init_begin,
 612 #ifdef CONFIG_ARM_LPAE
 613                 .mask   = ~L_PMD_SECT_RDONLY,
 614                 .prot   = L_PMD_SECT_RDONLY,
 615 #else
 616                 .mask   = ~(PMD_SECT_APX | PMD_SECT_AP_WRITE),
 617                 .prot   = PMD_SECT_APX | PMD_SECT_AP_WRITE,
 618                 .clear  = PMD_SECT_AP_WRITE,
 619 #endif
 620         },
 621 };
 622 #endif
 623
 624 /*
 625  * Updates section permissions only for the current mm (sections are
 626  * copied into each mm). During startup, this is the init_mm. Is only
 627  * safe to be called with preemption disabled, as under stop_machine().
 628  */
 629 static inline void section_update(unsigned long addr, pmdval_t mask,
 630                                   pmdval_t prot)
 631 {
 632         struct mm_struct *mm;
 633         pmd_t *pmd;
 634
 635         mm = current->active_mm;
 636         pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr);
 637
 638 #ifdef CONFIG_ARM_LPAE
 639         pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
 640 #else
 641         if (addr & SECTION_SIZE)
 642                 pmd[1] = __pmd((pmd_val(pmd[1]) & mask) | prot);
 643         else
 644                 pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
 645 #endif
 646         flush_pmd_entry(pmd);
 647         local_flush_tlb_kernel_range(addr, addr + SECTION_SIZE);
 648 }
 649
 650 /* Make sure extended page tables are in use. */
 651 static inline bool arch_has_strict_perms(void)
 652 {
 653         if (cpu_architecture() < CPU_ARCH_ARMv6)
 654                 return false;
 655
 656         return !!(get_cr() & CR_XP);
 657 }
 658
 659 #define set_section_perms(perms, field) {                               \
 660         size_t i;                                                       \
 661         unsigned long addr;                                             \
 662                                                                         \
 663         if (!arch_has_strict_perms())                                   \
 664                 return;                                                 \
 665                                                                         \
 666         for (i = 0; i < ARRAY_SIZE(perms); i++) {                       \
 667                 if (!IS_ALIGNED(perms[i].start, SECTION_SIZE) ||        \
 668                     !IS_ALIGNED(perms[i].end, SECTION_SIZE)) {          \
 669                         pr_err("BUG: section %lx-%lx not aligned to %lx\n", \
 670                                 perms[i].start, perms[i].end,           \
 671                                 SECTION_SIZE);                          \
 672                         continue;                                       \
 673                 }                                                       \
 674                                                                         \
 675                 for (addr = perms[i].start;                             \
 676                      addr < perms[i].end;                               \
 677                      addr += SECTION_SIZE)                              \
 678                         section_update(addr, perms[i].mask,             \
 679                                        perms[i].field);                 \
 680         }                                                               \
 681 }
 682
 683 static inline void fix_kernmem_perms(void)
 684 {
 685         set_section_perms(nx_perms, prot);
 686 }
 687
 688 #ifdef CONFIG_DEBUG_RODATA
 689 void mark_rodata_ro(void)
 690 {
 691         set_section_perms(ro_perms, prot);
 692 }
 693
 694 void set_kernel_text_rw(void)
 695 {
 696         set_section_perms(ro_perms, clear);
 697 }
 698
 699 void set_kernel_text_ro(void)
 700 {
 701         set_section_perms(ro_perms, prot);
 702 }
 703 #endif /* CONFIG_DEBUG_RODATA */
 704
 705 #else
 706 static inline void fix_kernmem_perms(void) { }
 707 #endif /* CONFIG_ARM_KERNMEM_PERMS */
 708
 709 void free_tcmmem(void)
 710 {
 711 #ifdef CONFIG_HAVE_TCM
 712         extern char __tcm_start, __tcm_end;
 713
 714         poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
 715         free_reserved_area(&__tcm_start, &__tcm_end, -1, "TCM link");
 716 #endif
 717 }
 718
 719 void free_initmem(void)
 720 {
 721         fix_kernmem_perms();
 722         free_tcmmem();
 723
 724         poison_init_mem(__init_begin, __init_end - __init_begin);
 725         if (!machine_is_integrator() && !machine_is_cintegrator())
 726                 free_initmem_default(-1);
 727 }
 728
 729 #ifdef CONFIG_BLK_DEV_INITRD
 730
 731 static int keep_initrd;
 732
 733 void free_initrd_mem(unsigned long start, unsigned long end)
 734 {
 735         if (!keep_initrd) {
 736                 if (start == initrd_start)
 737                         start = round_down(start, PAGE_SIZE);
 738                 if (end == initrd_end)
 739                         end = round_up(end, PAGE_SIZE);
 740
 741                 poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
 742                 free_reserved_area((void *)start, (void *)end, -1, "initrd");
 743         }
 744 }
 745
 746 static int __init keepinitrd_setup(char *__unused)
 747 {
 748         keep_initrd = 1;
 749         return 1;
 750 }
 751
 752 __setup("keepinitrd", keepinitrd_setup);
 753 #endif