1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Based on arch/arm/include/asm/memory.h
5 * Copyright (C) 2000-2002 Russell King
6 * Copyright (C) 2012 ARM Ltd.
8 * Note: this file should not be included by non-asm/.h files
10 #ifndef __ASM_MEMORY_H
11 #define __ASM_MEMORY_H
13 #include <linux/const.h>
14 #include <linux/sizes.h>
15 #include <asm/page-def.h>
18 * Size of the PCI I/O space. This must remain a power of two so that
19 * IO_SPACE_LIMIT acts as a mask for the low bits of I/O addresses.
21 #define PCI_IO_SIZE SZ_16M
24 * VMEMMAP_SIZE - allows the whole linear region to be covered by
27 * If we are configured with a 52-bit kernel VA then our VMEMMAP_SIZE
28 * needs to cover the memory region from the beginning of the 52-bit
29 * PAGE_OFFSET all the way to PAGE_END for 48-bit. This allows us to
30 * keep a constant PAGE_OFFSET and "fallback" to using the higher end
31 * of the VMEMMAP where 52-bit support is not available in hardware.
33 #define VMEMMAP_RANGE (_PAGE_END(VA_BITS_MIN) - PAGE_OFFSET)
34 #define VMEMMAP_SIZE ((VMEMMAP_RANGE >> PAGE_SHIFT) * sizeof(struct page))
37 * PAGE_OFFSET - the virtual address of the start of the linear map, at the
38 * start of the TTBR1 address space.
39 * PAGE_END - the end of the linear map, where all other kernel mappings begin.
40 * KIMAGE_VADDR - the virtual address of the start of the kernel image.
41 * VA_BITS - the maximum number of bits for virtual addresses.
43 #define VA_BITS (CONFIG_ARM64_VA_BITS)
44 #define _PAGE_OFFSET(va) (-(UL(1) << (va)))
45 #define PAGE_OFFSET (_PAGE_OFFSET(VA_BITS))
46 #define KIMAGE_VADDR (MODULES_END)
47 #define MODULES_END (MODULES_VADDR + MODULES_VSIZE)
48 #define MODULES_VADDR (_PAGE_END(VA_BITS_MIN))
49 #define MODULES_VSIZE (SZ_2G)
50 #define VMEMMAP_START (VMEMMAP_END - VMEMMAP_SIZE)
51 #define VMEMMAP_END (-UL(SZ_1G))
52 #define PCI_IO_START (VMEMMAP_END + SZ_8M)
53 #define PCI_IO_END (PCI_IO_START + PCI_IO_SIZE)
54 #define FIXADDR_TOP (-UL(SZ_8M))
57 #define VA_BITS_MIN (48)
59 #define VA_BITS_MIN (VA_BITS)
62 #define _PAGE_END(va) (-(UL(1) << ((va) - 1)))
64 #define KERNEL_START _text
65 #define KERNEL_END _end
68 * Generic and Software Tag-Based KASAN modes require 1/8th and 1/16th of the
69 * kernel virtual address space for storing the shadow memory respectively.
71 * The mapping between a virtual memory address and its corresponding shadow
72 * memory address is defined based on the formula:
74 * shadow_addr = (addr >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET
76 * where KASAN_SHADOW_SCALE_SHIFT is the order of the number of bits that map
77 * to a single shadow byte and KASAN_SHADOW_OFFSET is a constant that offsets
78 * the mapping. Note that KASAN_SHADOW_OFFSET does not point to the start of
79 * the shadow memory region.
81 * Based on this mapping, we define two constants:
83 * KASAN_SHADOW_START: the start of the shadow memory region;
84 * KASAN_SHADOW_END: the end of the shadow memory region.
86 * KASAN_SHADOW_END is defined first as the shadow address that corresponds to
87 * the upper bound of possible virtual kernel memory addresses UL(1) << 64
88 * according to the mapping formula.
90 * KASAN_SHADOW_START is defined second based on KASAN_SHADOW_END. The shadow
91 * memory start must map to the lowest possible kernel virtual memory address
92 * and thus it depends on the actual bitness of the address space.
94 * As KASAN inserts redzones between stack variables, this increases the stack
95 * memory usage significantly. Thus, we double the (minimum) stack size.
97 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
98 #define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
99 #define KASAN_SHADOW_END ((UL(1) << (64 - KASAN_SHADOW_SCALE_SHIFT)) + KASAN_SHADOW_OFFSET)
100 #define _KASAN_SHADOW_START(va) (KASAN_SHADOW_END - (UL(1) << ((va) - KASAN_SHADOW_SCALE_SHIFT)))
101 #define KASAN_SHADOW_START _KASAN_SHADOW_START(vabits_actual)
102 #define PAGE_END KASAN_SHADOW_START
103 #define KASAN_THREAD_SHIFT 1
105 #define KASAN_THREAD_SHIFT 0
106 #define PAGE_END (_PAGE_END(VA_BITS_MIN))
107 #endif /* CONFIG_KASAN */
109 #define MIN_THREAD_SHIFT (14 + KASAN_THREAD_SHIFT)
112 * VMAP'd stacks are allocated at page granularity, so we must ensure that such
113 * stacks are a multiple of page size.
115 #if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
116 #define THREAD_SHIFT PAGE_SHIFT
118 #define THREAD_SHIFT MIN_THREAD_SHIFT
121 #if THREAD_SHIFT >= PAGE_SHIFT
122 #define THREAD_SIZE_ORDER (THREAD_SHIFT - PAGE_SHIFT)
125 #define THREAD_SIZE (UL(1) << THREAD_SHIFT)
128 * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
129 * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
132 #ifdef CONFIG_VMAP_STACK
133 #define THREAD_ALIGN (2 * THREAD_SIZE)
135 #define THREAD_ALIGN THREAD_SIZE
138 #define IRQ_STACK_SIZE THREAD_SIZE
140 #define OVERFLOW_STACK_SIZE SZ_4K
143 * With the minimum frame size of [x29, x30], exactly half the combined
144 * sizes of the hyp and overflow stacks is the maximum size needed to
145 * save the unwinded stacktrace; plus an additional entry to delimit the
148 #define NVHE_STACKTRACE_SIZE ((OVERFLOW_STACK_SIZE + PAGE_SIZE) / 2 + sizeof(long))
151 * Alignment of kernel segments (e.g. .text, .data).
153 * 4 KB granule: 16 level 3 entries, with contiguous bit
154 * 16 KB granule: 4 level 3 entries, without contiguous bit
155 * 64 KB granule: 1 level 3 entry
157 #define SEGMENT_ALIGN SZ_64K
160 * Memory types available.
162 * IMPORTANT: MT_NORMAL must be index 0 since vm_get_page_prot() may 'or' in
163 * the MT_NORMAL_TAGGED memory type for PROT_MTE mappings. Note
164 * that protection_map[] only contains MT_NORMAL attributes.
167 #define MT_NORMAL_TAGGED 1
168 #define MT_NORMAL_NC 2
169 #define MT_DEVICE_nGnRnE 3
170 #define MT_DEVICE_nGnRE 4
173 * Memory types for Stage-2 translation
175 #define MT_S2_NORMAL 0xf
176 #define MT_S2_DEVICE_nGnRE 0x1
179 * Memory types for Stage-2 translation when ID_AA64MMFR2_EL1.FWB is 0001
180 * Stage-2 enforces Normal-WB and Device-nGnRE
182 #define MT_S2_FWB_NORMAL 6
183 #define MT_S2_FWB_DEVICE_nGnRE 1
185 #ifdef CONFIG_ARM64_4K_PAGES
186 #define IOREMAP_MAX_ORDER (PUD_SHIFT)
188 #define IOREMAP_MAX_ORDER (PMD_SHIFT)
192 * Open-coded (swapper_pg_dir - reserved_pg_dir) as this cannot be calculated
195 #define RESERVED_SWAPPER_OFFSET (PAGE_SIZE)
198 * Open-coded (swapper_pg_dir - tramp_pg_dir) as this cannot be calculated
201 #define TRAMP_SWAPPER_OFFSET (2 * PAGE_SIZE)
205 #include <linux/bitops.h>
206 #include <linux/compiler.h>
207 #include <linux/mmdebug.h>
208 #include <linux/types.h>
209 #include <asm/boot.h>
211 #include <asm/sections.h>
212 #include <asm/sysreg.h>
214 static inline u64 __pure read_tcr(void)
218 // read_sysreg() uses asm volatile, so avoid it here
219 asm("mrs %0, tcr_el1" : "=r"(tcr));
224 // For reasons of #include hell, we can't use TCR_T1SZ_OFFSET/TCR_T1SZ_MASK here
225 #define vabits_actual (64 - ((read_tcr() >> 16) & 63))
227 #define vabits_actual ((u64)VA_BITS)
230 extern s64 memstart_addr;
231 /* PHYS_OFFSET - the physical address of the start of memory. */
232 #define PHYS_OFFSET ({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
234 /* the offset between the kernel virtual and physical mappings */
235 extern u64 kimage_voffset;
237 static inline unsigned long kaslr_offset(void)
239 return (u64)&_text - KIMAGE_VADDR;
242 #ifdef CONFIG_RANDOMIZE_BASE
243 void kaslr_init(void);
244 static inline bool kaslr_enabled(void)
246 extern bool __kaslr_is_enabled;
247 return __kaslr_is_enabled;
250 static inline void kaslr_init(void) { }
251 static inline bool kaslr_enabled(void) { return false; }
255 * Allow all memory at the discovery stage. We will clip it later.
257 #define MIN_MEMBLOCK_ADDR 0
258 #define MAX_MEMBLOCK_ADDR U64_MAX
261 * PFNs are used to describe any physical page; this means
262 * PFN 0 == physical address 0.
264 * This is the PFN of the first RAM page in the kernel
265 * direct-mapped view. We assume this is the first page
266 * of RAM in the mem_map as well.
268 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
271 * When dealing with data aborts, watchpoints, or instruction traps we may end
272 * up with a tagged userland pointer. Clear the tag to get a sane pointer to
273 * pass on to access_ok(), for instance.
275 #define __untagged_addr(addr) \
276 ((__force __typeof__(addr))sign_extend64((__force u64)(addr), 55))
278 #define untagged_addr(addr) ({ \
279 u64 __addr = (__force u64)(addr); \
280 __addr &= __untagged_addr(__addr); \
281 (__force __typeof__(addr))__addr; \
284 #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
285 #define __tag_shifted(tag) ((u64)(tag) << 56)
286 #define __tag_reset(addr) __untagged_addr(addr)
287 #define __tag_get(addr) (__u8)((u64)(addr) >> 56)
289 #define __tag_shifted(tag) 0UL
290 #define __tag_reset(addr) (addr)
291 #define __tag_get(addr) 0
292 #endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
294 static inline const void *__tag_set(const void *addr, u8 tag)
296 u64 __addr = (u64)addr & ~__tag_shifted(0xff);
297 return (const void *)(__addr | __tag_shifted(tag));
300 #ifdef CONFIG_KASAN_HW_TAGS
301 #define arch_enable_tag_checks_sync() mte_enable_kernel_sync()
302 #define arch_enable_tag_checks_async() mte_enable_kernel_async()
303 #define arch_enable_tag_checks_asymm() mte_enable_kernel_asymm()
304 #define arch_suppress_tag_checks_start() mte_enable_tco()
305 #define arch_suppress_tag_checks_stop() mte_disable_tco()
306 #define arch_force_async_tag_fault() mte_check_tfsr_exit()
307 #define arch_get_random_tag() mte_get_random_tag()
308 #define arch_get_mem_tag(addr) mte_get_mem_tag(addr)
309 #define arch_set_mem_tag_range(addr, size, tag, init) \
310 mte_set_mem_tag_range((addr), (size), (tag), (init))
311 #endif /* CONFIG_KASAN_HW_TAGS */
314 * Physical vs virtual RAM address space conversion. These are
315 * private definitions which should NOT be used outside memory.h
316 * files. Use virt_to_phys/phys_to_virt/__pa/__va instead.
321 * Check whether an arbitrary address is within the linear map, which
322 * lives in the [PAGE_OFFSET, PAGE_END) interval at the bottom of the
323 * kernel's TTBR1 address range.
325 #define __is_lm_address(addr) (((u64)(addr) - PAGE_OFFSET) < (PAGE_END - PAGE_OFFSET))
327 #define __lm_to_phys(addr) (((addr) - PAGE_OFFSET) + PHYS_OFFSET)
328 #define __kimg_to_phys(addr) ((addr) - kimage_voffset)
330 #define __virt_to_phys_nodebug(x) ({ \
331 phys_addr_t __x = (phys_addr_t)(__tag_reset(x)); \
332 __is_lm_address(__x) ? __lm_to_phys(__x) : __kimg_to_phys(__x); \
335 #define __pa_symbol_nodebug(x) __kimg_to_phys((phys_addr_t)(x))
337 #ifdef CONFIG_DEBUG_VIRTUAL
338 extern phys_addr_t __virt_to_phys(unsigned long x);
339 extern phys_addr_t __phys_addr_symbol(unsigned long x);
341 #define __virt_to_phys(x) __virt_to_phys_nodebug(x)
342 #define __phys_addr_symbol(x) __pa_symbol_nodebug(x)
343 #endif /* CONFIG_DEBUG_VIRTUAL */
345 #define __phys_to_virt(x) ((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
346 #define __phys_to_kimg(x) ((unsigned long)((x) + kimage_voffset))
349 * Convert a page to/from a physical address
351 #define page_to_phys(page) (__pfn_to_phys(page_to_pfn(page)))
352 #define phys_to_page(phys) (pfn_to_page(__phys_to_pfn(phys)))
355 * Note: Drivers should NOT use these. They are the wrong
356 * translation for translating DMA addresses. Use the driver
357 * DMA support - see dma-mapping.h.
359 #define virt_to_phys virt_to_phys
360 static inline phys_addr_t virt_to_phys(const volatile void *x)
362 return __virt_to_phys((unsigned long)(x));
365 #define phys_to_virt phys_to_virt
366 static inline void *phys_to_virt(phys_addr_t x)
368 return (void *)(__phys_to_virt(x));
371 /* Needed already here for resolving __phys_to_pfn() in virt_to_pfn() */
372 #include <asm-generic/memory_model.h>
374 static inline unsigned long virt_to_pfn(const void *kaddr)
376 return __phys_to_pfn(virt_to_phys(kaddr));
380 * Drivers should NOT use these either.
382 #define __pa(x) __virt_to_phys((unsigned long)(x))
383 #define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
384 #define __pa_nodebug(x) __virt_to_phys_nodebug((unsigned long)(x))
385 #define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x)))
386 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
387 #define sym_to_pfn(x) __phys_to_pfn(__pa_symbol(x))
390 * virt_to_page(x) convert a _valid_ virtual address to struct page *
391 * virt_addr_valid(x) indicates whether a virtual address is valid
393 #define ARCH_PFN_OFFSET ((unsigned long)PHYS_PFN_OFFSET)
395 #if defined(CONFIG_DEBUG_VIRTUAL)
396 #define page_to_virt(x) ({ \
397 __typeof__(x) __page = x; \
398 void *__addr = __va(page_to_phys(__page)); \
399 (void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\
401 #define virt_to_page(x) pfn_to_page(virt_to_pfn(x))
403 #define page_to_virt(x) ({ \
404 __typeof__(x) __page = x; \
405 u64 __idx = ((u64)__page - VMEMMAP_START) / sizeof(struct page);\
406 u64 __addr = PAGE_OFFSET + (__idx * PAGE_SIZE); \
407 (void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\
410 #define virt_to_page(x) ({ \
411 u64 __idx = (__tag_reset((u64)x) - PAGE_OFFSET) / PAGE_SIZE; \
412 u64 __addr = VMEMMAP_START + (__idx * sizeof(struct page)); \
413 (struct page *)__addr; \
415 #endif /* CONFIG_DEBUG_VIRTUAL */
417 #define virt_addr_valid(addr) ({ \
418 __typeof__(addr) __addr = __tag_reset(addr); \
419 __is_lm_address(__addr) && pfn_is_map_memory(virt_to_pfn(__addr)); \
422 void dump_mem_limit(void);
423 #endif /* !ASSEMBLY */
426 * Given that the GIC architecture permits ITS implementations that can only be
427 * configured with a LPI table address once, GICv3 systems with many CPUs may
428 * end up reserving a lot of different regions after a kexec for their LPI
429 * tables (one per CPU), as we are forced to reuse the same memory after kexec
430 * (and thus reserve it persistently with EFI beforehand)
432 #if defined(CONFIG_EFI) && defined(CONFIG_ARM_GIC_V3_ITS)
433 # define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CPUS + 1)
437 * memory regions which marked with flag MEMBLOCK_NOMAP(for example, the memory
438 * of the EFI_UNUSABLE_MEMORY type) may divide a continuous memory block into
439 * multiple parts. As a result, the number of memory regions is large.
442 #define INIT_MEMBLOCK_MEMORY_REGIONS (INIT_MEMBLOCK_REGIONS * 8)
446 #endif /* __ASM_MEMORY_H */