arch/arm64/include/asm/memory.h

   1 /*
   2  * Based on arch/arm/include/asm/memory.h
   3  *
   4  * Copyright (C) 2000-2002 Russell King
   5  * Copyright (C) 2012 ARM Ltd.
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  *
  19  * Note: this file should not be included by non-asm/.h files
  20  */
  21 #ifndef __ASM_MEMORY_H
  22 #define __ASM_MEMORY_H
  23
  24 #include <linux/compiler.h>
  25 #include <linux/const.h>
  26 #include <linux/types.h>
  27 #include <asm/bug.h>
  28 #include <asm/page-def.h>
  29 #include <asm/sizes.h>
  30
  31 /*
  32  * Allow for constants defined here to be used from assembly code
  33  * by prepending the UL suffix only with actual C code compilation.
  34  */
  35 #define UL(x) _AC(x, UL)
  36
  37 /*
  38  * Size of the PCI I/O space. This must remain a power of two so that
  39  * IO_SPACE_LIMIT acts as a mask for the low bits of I/O addresses.
  40  */
  41 #define PCI_IO_SIZE             SZ_16M
  42
  43 /*
  44  * Log2 of the upper bound of the size of a struct page. Used for sizing
  45  * the vmemmap region only, does not affect actual memory footprint.
  46  * We don't use sizeof(struct page) directly since taking its size here
  47  * requires its definition to be available at this point in the inclusion
  48  * chain, and it may not be a power of 2 in the first place.
  49  */
  50 #define STRUCT_PAGE_MAX_SHIFT   6
  51
  52 /*
  53  * VMEMMAP_SIZE - allows the whole linear region to be covered by
  54  *                a struct page array
  55  */
  56 #define VMEMMAP_SIZE (UL(1) << (VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT))
  57
  58 /*
  59  * PAGE_OFFSET - the virtual address of the start of the linear map (top
  60  *               (VA_BITS - 1))
  61  * KIMAGE_VADDR - the virtual address of the start of the kernel image
  62  * VA_BITS - the maximum number of bits for virtual addresses.
  63  * VA_START - the first kernel virtual address.
  64  */
  65 #define VA_BITS                 (CONFIG_ARM64_VA_BITS)
  66 #define VA_START                (UL(0xffffffffffffffff) - \
  67         (UL(1) << VA_BITS) + 1)
  68 #define PAGE_OFFSET             (UL(0xffffffffffffffff) - \
  69         (UL(1) << (VA_BITS - 1)) + 1)
  70 #define KIMAGE_VADDR            (MODULES_END)
  71 #define MODULES_END             (MODULES_VADDR + MODULES_VSIZE)
  72 #define MODULES_VADDR           (VA_START + KASAN_SHADOW_SIZE)
  73 #define MODULES_VSIZE           (SZ_128M)
  74 #define VMEMMAP_START           (PAGE_OFFSET - VMEMMAP_SIZE)
  75 #define PCI_IO_END              (VMEMMAP_START - SZ_2M)
  76 #define PCI_IO_START            (PCI_IO_END - PCI_IO_SIZE)
  77 #define FIXADDR_TOP             (PCI_IO_START - SZ_2M)
  78
  79 #define KERNEL_START      _text
  80 #define KERNEL_END        _end
  81
  82 /*
  83  * KASAN requires 1/8th of the kernel virtual address space for the shadow
  84  * region. KASAN can bloat the stack significantly, so double the (minimum)
  85  * stack size when KASAN is in use.
  86  */
  87 #ifdef CONFIG_KASAN
  88 #define KASAN_SHADOW_SIZE       (UL(1) << (VA_BITS - 3))
  89 #define KASAN_THREAD_SHIFT      1
  90 #else
  91 #define KASAN_SHADOW_SIZE       (0)
  92 #define KASAN_THREAD_SHIFT      0
  93 #endif
  94
  95 #define MIN_THREAD_SHIFT        (14 + KASAN_THREAD_SHIFT)
  96
  97 /*
  98  * VMAP'd stacks are allocated at page granularity, so we must ensure that such
  99  * stacks are a multiple of page size.
 100  */
 101 #if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
 102 #define THREAD_SHIFT            PAGE_SHIFT
 103 #else
 104 #define THREAD_SHIFT            MIN_THREAD_SHIFT
 105 #endif
 106
 107 #if THREAD_SHIFT >= PAGE_SHIFT
 108 #define THREAD_SIZE_ORDER       (THREAD_SHIFT - PAGE_SHIFT)
 109 #endif
 110
 111 #define THREAD_SIZE             (UL(1) << THREAD_SHIFT)
 112
 113 /*
 114  * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
 115  * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
 116  * assembly.
 117  */
 118 #ifdef CONFIG_VMAP_STACK
 119 #define THREAD_ALIGN            (2 * THREAD_SIZE)
 120 #else
 121 #define THREAD_ALIGN            THREAD_SIZE
 122 #endif
 123
 124 #define IRQ_STACK_SIZE          THREAD_SIZE
 125
 126 #define OVERFLOW_STACK_SIZE     SZ_4K
 127
 128 /*
 129  * Alignment of kernel segments (e.g. .text, .data).
 130  */
 131 #if defined(CONFIG_DEBUG_ALIGN_RODATA)
 132 /*
 133  *  4 KB granule:   1 level 2 entry
 134  * 16 KB granule: 128 level 3 entries, with contiguous bit
 135  * 64 KB granule:  32 level 3 entries, with contiguous bit
 136  */
 137 #define SEGMENT_ALIGN                   SZ_2M
 138 #else
 139 /*
 140  *  4 KB granule:  16 level 3 entries, with contiguous bit
 141  * 16 KB granule:   4 level 3 entries, without contiguous bit
 142  * 64 KB granule:   1 level 3 entry
 143  */
 144 #define SEGMENT_ALIGN                   SZ_64K
 145 #endif
 146
 147 /*
 148  * Memory types available.
 149  */
 150 #define MT_DEVICE_nGnRnE        0
 151 #define MT_DEVICE_nGnRE         1
 152 #define MT_DEVICE_GRE           2
 153 #define MT_NORMAL_NC            3
 154 #define MT_NORMAL               4
 155 #define MT_NORMAL_WT            5
 156
 157 /*
 158  * Memory types for Stage-2 translation
 159  */
 160 #define MT_S2_NORMAL            0xf
 161 #define MT_S2_DEVICE_nGnRE      0x1
 162
 163 #ifdef CONFIG_ARM64_4K_PAGES
 164 #define IOREMAP_MAX_ORDER       (PUD_SHIFT)
 165 #else
 166 #define IOREMAP_MAX_ORDER       (PMD_SHIFT)
 167 #endif
 168
 169 #ifdef CONFIG_BLK_DEV_INITRD
 170 #define __early_init_dt_declare_initrd(__start, __end)                  \
 171         do {                                                            \
 172                 initrd_start = (__start);                               \
 173                 initrd_end = (__end);                                   \
 174         } while (0)
 175 #endif
 176
 177 #ifndef __ASSEMBLY__
 178
 179 #include <linux/bitops.h>
 180 #include <linux/mmdebug.h>
 181
 182 extern s64                      memstart_addr;
 183 /* PHYS_OFFSET - the physical address of the start of memory. */
 184 #define PHYS_OFFSET             ({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
 185
 186 /* the virtual base of the kernel image (minus TEXT_OFFSET) */
 187 extern u64                      kimage_vaddr;
 188
 189 /* the offset between the kernel virtual and physical mappings */
 190 extern u64                      kimage_voffset;
 191
 192 static inline unsigned long kaslr_offset(void)
 193 {
 194         return kimage_vaddr - KIMAGE_VADDR;
 195 }
 196
 197 /*
 198  * Allow all memory at the discovery stage. We will clip it later.
 199  */
 200 #define MIN_MEMBLOCK_ADDR       0
 201 #define MAX_MEMBLOCK_ADDR       U64_MAX
 202
 203 /*
 204  * PFNs are used to describe any physical page; this means
 205  * PFN 0 == physical address 0.
 206  *
 207  * This is the PFN of the first RAM page in the kernel
 208  * direct-mapped view.  We assume this is the first page
 209  * of RAM in the mem_map as well.
 210  */
 211 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
 212
 213 /*
 214  * Physical vs virtual RAM address space conversion.  These are
 215  * private definitions which should NOT be used outside memory.h
 216  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
 217  */
 218
 219
 220 /*
 221  * The linear kernel range starts in the middle of the virtual adddress
 222  * space. Testing the top bit for the start of the region is a
 223  * sufficient check.
 224  */
 225 #define __is_lm_address(addr)   (!!((addr) & BIT(VA_BITS - 1)))
 226
 227 #define __lm_to_phys(addr)      (((addr) & ~PAGE_OFFSET) + PHYS_OFFSET)
 228 #define __kimg_to_phys(addr)    ((addr) - kimage_voffset)
 229
 230 #define __virt_to_phys_nodebug(x) ({                                    \
 231         phys_addr_t __x = (phys_addr_t)(x);                             \
 232         __is_lm_address(__x) ? __lm_to_phys(__x) :                      \
 233                                __kimg_to_phys(__x);                     \
 234 })
 235
 236 #define __pa_symbol_nodebug(x)  __kimg_to_phys((phys_addr_t)(x))
 237
 238 #ifdef CONFIG_DEBUG_VIRTUAL
 239 extern phys_addr_t __virt_to_phys(unsigned long x);
 240 extern phys_addr_t __phys_addr_symbol(unsigned long x);
 241 #else
 242 #define __virt_to_phys(x)       __virt_to_phys_nodebug(x)
 243 #define __phys_addr_symbol(x)   __pa_symbol_nodebug(x)
 244 #endif
 245
 246 #define __phys_to_virt(x)       ((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
 247 #define __phys_to_kimg(x)       ((unsigned long)((x) + kimage_voffset))
 248
 249 /*
 250  * Convert a page to/from a physical address
 251  */
 252 #define page_to_phys(page)      (__pfn_to_phys(page_to_pfn(page)))
 253 #define phys_to_page(phys)      (pfn_to_page(__phys_to_pfn(phys)))
 254
 255 /*
 256  * Note: Drivers should NOT use these.  They are the wrong
 257  * translation for translating DMA addresses.  Use the driver
 258  * DMA support - see dma-mapping.h.
 259  */
 260 #define virt_to_phys virt_to_phys
 261 static inline phys_addr_t virt_to_phys(const volatile void *x)
 262 {
 263         return __virt_to_phys((unsigned long)(x));
 264 }
 265
 266 #define phys_to_virt phys_to_virt
 267 static inline void *phys_to_virt(phys_addr_t x)
 268 {
 269         return (void *)(__phys_to_virt(x));
 270 }
 271
 272 /*
 273  * Drivers should NOT use these either.
 274  */
 275 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 276 #define __pa_symbol(x)          __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
 277 #define __pa_nodebug(x)         __virt_to_phys_nodebug((unsigned long)(x))
 278 #define __va(x)                 ((void *)__phys_to_virt((phys_addr_t)(x)))
 279 #define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 280 #define virt_to_pfn(x)      __phys_to_pfn(__virt_to_phys((unsigned long)(x)))
 281 #define sym_to_pfn(x)       __phys_to_pfn(__pa_symbol(x))
 282
 283 /*
 284  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 285  *  virt_addr_valid(k)  indicates whether a virtual address is valid
 286  */
 287 #define ARCH_PFN_OFFSET         ((unsigned long)PHYS_PFN_OFFSET)
 288
 289 #ifndef CONFIG_SPARSEMEM_VMEMMAP
 290 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 291 #define _virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
 292 #else
 293 #define __virt_to_pgoff(kaddr)  (((u64)(kaddr) & ~PAGE_OFFSET) / PAGE_SIZE * sizeof(struct page))
 294 #define __page_to_voff(kaddr)   (((u64)(kaddr) & ~VMEMMAP_START) * PAGE_SIZE / sizeof(struct page))
 295
 296 #define page_to_virt(page)      ((void *)((__page_to_voff(page)) | PAGE_OFFSET))
 297 #define virt_to_page(vaddr)     ((struct page *)((__virt_to_pgoff(vaddr)) | VMEMMAP_START))
 298
 299 #define _virt_addr_valid(kaddr) pfn_valid((((u64)(kaddr) & ~PAGE_OFFSET) \
 300                                            + PHYS_OFFSET) >> PAGE_SHIFT)
 301 #endif
 302 #endif
 303
 304 #define _virt_addr_is_linear(kaddr)     (((u64)(kaddr)) >= PAGE_OFFSET)
 305 #define virt_addr_valid(kaddr)          (_virt_addr_is_linear(kaddr) && \
 306                                          _virt_addr_valid(kaddr))
 307
 308 #include <asm-generic/memory_model.h>
 309
 310 #endif