arch/arm64/include/asm/memory.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Based on arch/arm/include/asm/memory.h
   4  *
   5  * Copyright (C) 2000-2002 Russell King
   6  * Copyright (C) 2012 ARM Ltd.
   7  *
   8  * Note: this file should not be included by non-asm/.h files
   9  */
  10 #ifndef __ASM_MEMORY_H
  11 #define __ASM_MEMORY_H
  12
  13 #include <linux/compiler.h>
  14 #include <linux/const.h>
  15 #include <linux/sizes.h>
  16 #include <linux/types.h>
  17 #include <asm/bug.h>
  18 #include <asm/page-def.h>
  19
  20 /*
  21  * Size of the PCI I/O space. This must remain a power of two so that
  22  * IO_SPACE_LIMIT acts as a mask for the low bits of I/O addresses.
  23  */
  24 #define PCI_IO_SIZE             SZ_16M
  25
  26 /*
  27  * VMEMMAP_SIZE - allows the whole linear region to be covered by
  28  *                a struct page array
  29  *
  30  * If we are configured with a 52-bit kernel VA then our VMEMMAP_SIZE
  31  * needs to cover the memory region from the beginning of the 52-bit
  32  * PAGE_OFFSET all the way to PAGE_END for 48-bit. This allows us to
  33  * keep a constant PAGE_OFFSET and "fallback" to using the higher end
  34  * of the VMEMMAP where 52-bit support is not available in hardware.
  35  */
  36 #define VMEMMAP_SIZE ((_PAGE_END(VA_BITS_MIN) - PAGE_OFFSET) \
  37                         >> (PAGE_SHIFT - STRUCT_PAGE_MAX_SHIFT))
  38
  39 /*
  40  * PAGE_OFFSET - the virtual address of the start of the linear map, at the
  41  *               start of the TTBR1 address space.
  42  * PAGE_END - the end of the linear map, where all other kernel mappings begin.
  43  * KIMAGE_VADDR - the virtual address of the start of the kernel image.
  44  * VA_BITS - the maximum number of bits for virtual addresses.
  45  */
  46 #define VA_BITS                 (CONFIG_ARM64_VA_BITS)
  47 #define _PAGE_OFFSET(va)        (-(UL(1) << (va)))
  48 #define PAGE_OFFSET             (_PAGE_OFFSET(VA_BITS))
  49 #define KIMAGE_VADDR            (MODULES_END)
  50 #define BPF_JIT_REGION_START    (KASAN_SHADOW_END)
  51 #define BPF_JIT_REGION_SIZE     (SZ_128M)
  52 #define BPF_JIT_REGION_END      (BPF_JIT_REGION_START + BPF_JIT_REGION_SIZE)
  53 #define MODULES_END             (MODULES_VADDR + MODULES_VSIZE)
  54 #define MODULES_VADDR           (BPF_JIT_REGION_END)
  55 #define MODULES_VSIZE           (SZ_128M)
  56 #define VMEMMAP_START           (-VMEMMAP_SIZE - SZ_2M)
  57 #define PCI_IO_END              (VMEMMAP_START - SZ_2M)
  58 #define PCI_IO_START            (PCI_IO_END - PCI_IO_SIZE)
  59 #define FIXADDR_TOP             (PCI_IO_START - SZ_2M)
  60
  61 #if VA_BITS > 48
  62 #define VA_BITS_MIN             (48)
  63 #else
  64 #define VA_BITS_MIN             (VA_BITS)
  65 #endif
  66
  67 #define _PAGE_END(va)           (-(UL(1) << ((va) - 1)))
  68
  69 #define KERNEL_START            _text
  70 #define KERNEL_END              _end
  71
  72 /*
  73  * Generic and tag-based KASAN require 1/8th and 1/16th of the kernel virtual
  74  * address space for the shadow region respectively. They can bloat the stack
  75  * significantly, so double the (minimum) stack size when they are in use.
  76  */
  77 #ifdef CONFIG_KASAN
  78 #define KASAN_SHADOW_OFFSET     _AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
  79 #define KASAN_SHADOW_END        ((UL(1) << (64 - KASAN_SHADOW_SCALE_SHIFT)) \
  80                                         + KASAN_SHADOW_OFFSET)
  81 #define KASAN_THREAD_SHIFT      1
  82 #else
  83 #define KASAN_THREAD_SHIFT      0
  84 #define KASAN_SHADOW_END        (_PAGE_END(VA_BITS_MIN))
  85 #endif /* CONFIG_KASAN */
  86
  87 #define MIN_THREAD_SHIFT        (14 + KASAN_THREAD_SHIFT)
  88
  89 /*
  90  * VMAP'd stacks are allocated at page granularity, so we must ensure that such
  91  * stacks are a multiple of page size.
  92  */
  93 #if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
  94 #define THREAD_SHIFT            PAGE_SHIFT
  95 #else
  96 #define THREAD_SHIFT            MIN_THREAD_SHIFT
  97 #endif
  98
  99 #if THREAD_SHIFT >= PAGE_SHIFT
 100 #define THREAD_SIZE_ORDER       (THREAD_SHIFT - PAGE_SHIFT)
 101 #endif
 102
 103 #define THREAD_SIZE             (UL(1) << THREAD_SHIFT)
 104
 105 /*
 106  * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
 107  * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
 108  * assembly.
 109  */
 110 #ifdef CONFIG_VMAP_STACK
 111 #define THREAD_ALIGN            (2 * THREAD_SIZE)
 112 #else
 113 #define THREAD_ALIGN            THREAD_SIZE
 114 #endif
 115
 116 #define IRQ_STACK_SIZE          THREAD_SIZE
 117
 118 #define OVERFLOW_STACK_SIZE     SZ_4K
 119
 120 /*
 121  * Alignment of kernel segments (e.g. .text, .data).
 122  */
 123 #if defined(CONFIG_DEBUG_ALIGN_RODATA)
 124 /*
 125  *  4 KB granule:   1 level 2 entry
 126  * 16 KB granule: 128 level 3 entries, with contiguous bit
 127  * 64 KB granule:  32 level 3 entries, with contiguous bit
 128  */
 129 #define SEGMENT_ALIGN           SZ_2M
 130 #else
 131 /*
 132  *  4 KB granule:  16 level 3 entries, with contiguous bit
 133  * 16 KB granule:   4 level 3 entries, without contiguous bit
 134  * 64 KB granule:   1 level 3 entry
 135  */
 136 #define SEGMENT_ALIGN           SZ_64K
 137 #endif
 138
 139 /*
 140  * Memory types available.
 141  */
 142 #define MT_DEVICE_nGnRnE        0
 143 #define MT_DEVICE_nGnRE         1
 144 #define MT_DEVICE_GRE           2
 145 #define MT_NORMAL_NC            3
 146 #define MT_NORMAL               4
 147 #define MT_NORMAL_WT            5
 148
 149 /*
 150  * Memory types for Stage-2 translation
 151  */
 152 #define MT_S2_NORMAL            0xf
 153 #define MT_S2_DEVICE_nGnRE      0x1
 154
 155 /*
 156  * Memory types for Stage-2 translation when ID_AA64MMFR2_EL1.FWB is 0001
 157  * Stage-2 enforces Normal-WB and Device-nGnRE
 158  */
 159 #define MT_S2_FWB_NORMAL        6
 160 #define MT_S2_FWB_DEVICE_nGnRE  1
 161
 162 #ifdef CONFIG_ARM64_4K_PAGES
 163 #define IOREMAP_MAX_ORDER       (PUD_SHIFT)
 164 #else
 165 #define IOREMAP_MAX_ORDER       (PMD_SHIFT)
 166 #endif
 167
 168 #ifndef __ASSEMBLY__
 169 extern u64                      vabits_actual;
 170 #define PAGE_END                (_PAGE_END(vabits_actual))
 171
 172 #include <linux/bitops.h>
 173 #include <linux/mmdebug.h>
 174
 175 extern s64                      physvirt_offset;
 176 extern s64                      memstart_addr;
 177 /* PHYS_OFFSET - the physical address of the start of memory. */
 178 #define PHYS_OFFSET             ({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
 179
 180 /* the virtual base of the kernel image (minus TEXT_OFFSET) */
 181 extern u64                      kimage_vaddr;
 182
 183 /* the offset between the kernel virtual and physical mappings */
 184 extern u64                      kimage_voffset;
 185
 186 static inline unsigned long kaslr_offset(void)
 187 {
 188         return kimage_vaddr - KIMAGE_VADDR;
 189 }
 190
 191 /*
 192  * Allow all memory at the discovery stage. We will clip it later.
 193  */
 194 #define MIN_MEMBLOCK_ADDR       0
 195 #define MAX_MEMBLOCK_ADDR       U64_MAX
 196
 197 /*
 198  * PFNs are used to describe any physical page; this means
 199  * PFN 0 == physical address 0.
 200  *
 201  * This is the PFN of the first RAM page in the kernel
 202  * direct-mapped view.  We assume this is the first page
 203  * of RAM in the mem_map as well.
 204  */
 205 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
 206
 207 /*
 208  * When dealing with data aborts, watchpoints, or instruction traps we may end
 209  * up with a tagged userland pointer. Clear the tag to get a sane pointer to
 210  * pass on to access_ok(), for instance.
 211  */
 212 #define __untagged_addr(addr)   \
 213         ((__force __typeof__(addr))sign_extend64((__force u64)(addr), 55))
 214
 215 #define untagged_addr(addr)     ({                                      \
 216         u64 __addr = (__force u64)(addr);                                       \
 217         __addr &= __untagged_addr(__addr);                              \
 218         (__force __typeof__(addr))__addr;                               \
 219 })
 220
 221 #ifdef CONFIG_KASAN_SW_TAGS
 222 #define __tag_shifted(tag)      ((u64)(tag) << 56)
 223 #define __tag_reset(addr)       __untagged_addr(addr)
 224 #define __tag_get(addr)         (__u8)((u64)(addr) >> 56)
 225 #else
 226 #define __tag_shifted(tag)      0UL
 227 #define __tag_reset(addr)       (addr)
 228 #define __tag_get(addr)         0
 229 #endif /* CONFIG_KASAN_SW_TAGS */
 230
 231 static inline const void *__tag_set(const void *addr, u8 tag)
 232 {
 233         u64 __addr = (u64)addr & ~__tag_shifted(0xff);
 234         return (const void *)(__addr | __tag_shifted(tag));
 235 }
 236
 237 /*
 238  * Physical vs virtual RAM address space conversion.  These are
 239  * private definitions which should NOT be used outside memory.h
 240  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
 241  */
 242
 243
 244 /*
 245  * The linear kernel range starts at the bottom of the virtual address
 246  * space. Testing the top bit for the start of the region is a
 247  * sufficient check and avoids having to worry about the tag.
 248  */
 249 #define __is_lm_address(addr)   (!(((u64)addr) & BIT(vabits_actual - 1)))
 250
 251 #define __lm_to_phys(addr)      (((addr) + physvirt_offset))
 252 #define __kimg_to_phys(addr)    ((addr) - kimage_voffset)
 253
 254 #define __virt_to_phys_nodebug(x) ({                                    \
 255         phys_addr_t __x = (phys_addr_t)(__tag_reset(x));                \
 256         __is_lm_address(__x) ? __lm_to_phys(__x) : __kimg_to_phys(__x); \
 257 })
 258
 259 #define __pa_symbol_nodebug(x)  __kimg_to_phys((phys_addr_t)(x))
 260
 261 #ifdef CONFIG_DEBUG_VIRTUAL
 262 extern phys_addr_t __virt_to_phys(unsigned long x);
 263 extern phys_addr_t __phys_addr_symbol(unsigned long x);
 264 #else
 265 #define __virt_to_phys(x)       __virt_to_phys_nodebug(x)
 266 #define __phys_addr_symbol(x)   __pa_symbol_nodebug(x)
 267 #endif /* CONFIG_DEBUG_VIRTUAL */
 268
 269 #define __phys_to_virt(x)       ((unsigned long)((x) - physvirt_offset))
 270 #define __phys_to_kimg(x)       ((unsigned long)((x) + kimage_voffset))
 271
 272 /*
 273  * Convert a page to/from a physical address
 274  */
 275 #define page_to_phys(page)      (__pfn_to_phys(page_to_pfn(page)))
 276 #define phys_to_page(phys)      (pfn_to_page(__phys_to_pfn(phys)))
 277
 278 /*
 279  * Note: Drivers should NOT use these.  They are the wrong
 280  * translation for translating DMA addresses.  Use the driver
 281  * DMA support - see dma-mapping.h.
 282  */
 283 #define virt_to_phys virt_to_phys
 284 static inline phys_addr_t virt_to_phys(const volatile void *x)
 285 {
 286         return __virt_to_phys((unsigned long)(x));
 287 }
 288
 289 #define phys_to_virt phys_to_virt
 290 static inline void *phys_to_virt(phys_addr_t x)
 291 {
 292         return (void *)(__phys_to_virt(x));
 293 }
 294
 295 /*
 296  * Drivers should NOT use these either.
 297  */
 298 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 299 #define __pa_symbol(x)          __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
 300 #define __pa_nodebug(x)         __virt_to_phys_nodebug((unsigned long)(x))
 301 #define __va(x)                 ((void *)__phys_to_virt((phys_addr_t)(x)))
 302 #define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 303 #define virt_to_pfn(x)          __phys_to_pfn(__virt_to_phys((unsigned long)(x)))
 304 #define sym_to_pfn(x)           __phys_to_pfn(__pa_symbol(x))
 305
 306 /*
 307  *  virt_to_page(x)     convert a _valid_ virtual address to struct page *
 308  *  virt_addr_valid(x)  indicates whether a virtual address is valid
 309  */
 310 #define ARCH_PFN_OFFSET         ((unsigned long)PHYS_PFN_OFFSET)
 311
 312 #if !defined(CONFIG_SPARSEMEM_VMEMMAP) || defined(CONFIG_DEBUG_VIRTUAL)
 313 #define virt_to_page(x)         pfn_to_page(virt_to_pfn(x))
 314 #else
 315 #define page_to_virt(x) ({                                              \
 316         __typeof__(x) __page = x;                                       \
 317         u64 __idx = ((u64)__page - VMEMMAP_START) / sizeof(struct page);\
 318         u64 __addr = PAGE_OFFSET + (__idx * PAGE_SIZE);                 \
 319         (void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\
 320 })
 321
 322 #define virt_to_page(x) ({                                              \
 323         u64 __idx = (__tag_reset((u64)x) - PAGE_OFFSET) / PAGE_SIZE;    \
 324         u64 __addr = VMEMMAP_START + (__idx * sizeof(struct page));     \
 325         (struct page *)__addr;                                          \
 326 })
 327 #endif /* !CONFIG_SPARSEMEM_VMEMMAP || CONFIG_DEBUG_VIRTUAL */
 328
 329 #define virt_addr_valid(addr)   ({                                      \
 330         __typeof__(addr) __addr = addr;                                 \
 331         __is_lm_address(__addr) && pfn_valid(virt_to_pfn(__addr));      \
 332 })
 333
 334 #endif /* !ASSEMBLY */
 335
 336 /*
 337  * Given that the GIC architecture permits ITS implementations that can only be
 338  * configured with a LPI table address once, GICv3 systems with many CPUs may
 339  * end up reserving a lot of different regions after a kexec for their LPI
 340  * tables (one per CPU), as we are forced to reuse the same memory after kexec
 341  * (and thus reserve it persistently with EFI beforehand)
 342  */
 343 #if defined(CONFIG_EFI) && defined(CONFIG_ARM_GIC_V3_ITS)
 344 # define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CPUS + 1)
 345 #endif
 346
 347 #include <asm-generic/memory_model.h>
 348
 349 #endif /* __ASM_MEMORY_H */