/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Based on arch/arm/include/asm/memory.h
 *
 * Copyright (C) 2000-2002 Russell King
 * Copyright (C) 2012 ARM Ltd.
 *
 * Note: this file should not be included by non-asm/.h files
 */
#ifndef __ASM_MEMORY_H
#define __ASM_MEMORY_H

#include <linux/const.h>
#include <linux/sizes.h>
#include <asm/page-def.h>

/*
 * Size of the PCI I/O space. This must remain a power of two so that
 * IO_SPACE_LIMIT acts as a mask for the low bits of I/O addresses.
 */
#define PCI_IO_SIZE             SZ_16M

/*
 * VMEMMAP_SIZE - allows the whole linear region to be covered by
 *                a struct page array
 *
 * If we are configured with a 52-bit kernel VA then our VMEMMAP_SIZE
 * needs to cover the memory region from the beginning of the 52-bit
 * PAGE_OFFSET all the way to PAGE_END for 48-bit. This allows us to
 * keep a constant PAGE_OFFSET and "fallback" to using the higher end
 * of the VMEMMAP where 52-bit support is not available in hardware.
 */
#define VMEMMAP_RANGE   (_PAGE_END(VA_BITS_MIN) - PAGE_OFFSET)
#define VMEMMAP_SIZE    ((VMEMMAP_RANGE >> PAGE_SHIFT) * sizeof(struct page))

/*
 * PAGE_OFFSET - the virtual address of the start of the linear map, at the
 *               start of the TTBR1 address space.
 * PAGE_END - the end of the linear map, where all other kernel mappings begin.
 * KIMAGE_VADDR - the virtual address of the start of the kernel image.
 * VA_BITS - the maximum number of bits for virtual addresses.
 */
#define VA_BITS                 (CONFIG_ARM64_VA_BITS)
#define _PAGE_OFFSET(va)        (-(UL(1) << (va)))
#define PAGE_OFFSET             (_PAGE_OFFSET(VA_BITS))
#define KIMAGE_VADDR            (MODULES_END)
#define MODULES_END             (MODULES_VADDR + MODULES_VSIZE)
#define MODULES_VADDR           (_PAGE_END(VA_BITS_MIN))
#define MODULES_VSIZE           (SZ_2G)
#define VMEMMAP_START           (VMEMMAP_END - VMEMMAP_SIZE)
#define VMEMMAP_END             (-UL(SZ_1G))
#define PCI_IO_START            (VMEMMAP_END + SZ_8M)
#define PCI_IO_END              (PCI_IO_START + PCI_IO_SIZE)
#define FIXADDR_TOP             (-UL(SZ_8M))

#if VA_BITS > 48
#ifdef CONFIG_ARM64_16K_PAGES
#define VA_BITS_MIN             (47)
#else
#define VA_BITS_MIN             (48)
#endif
#else
#define VA_BITS_MIN             (VA_BITS)
#endif

#define _PAGE_END(va)           (-(UL(1) << ((va) - 1)))

#define KERNEL_START            _text
#define KERNEL_END              _end

/*
 * Generic and Software Tag-Based KASAN modes require 1/8th and 1/16th of the
 * kernel virtual address space for storing the shadow memory respectively.
 *
 * The mapping between a virtual memory address and its corresponding shadow
 * memory address is defined based on the formula:
 *
 *     shadow_addr = (addr >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET
 *
 * where KASAN_SHADOW_SCALE_SHIFT is the order of the number of bits that map
 * to a single shadow byte and KASAN_SHADOW_OFFSET is a constant that offsets
 * the mapping. Note that KASAN_SHADOW_OFFSET does not point to the start of
 * the shadow memory region.
 *
 * Based on this mapping, we define two constants:
 *
 *     KASAN_SHADOW_START: the start of the shadow memory region;
 *     KASAN_SHADOW_END: the end of the shadow memory region.
 *
 * KASAN_SHADOW_END is defined first as the shadow address that corresponds to
 * the upper bound of possible virtual kernel memory addresses UL(1) << 64
 * according to the mapping formula.
 *
 * KASAN_SHADOW_START is defined second based on KASAN_SHADOW_END. The shadow
 * memory start must map to the lowest possible kernel virtual memory address
 * and thus it depends on the actual bitness of the address space.
 *
 * As KASAN inserts redzones between stack variables, this increases the stack
 * memory usage significantly. Thus, we double the (minimum) stack size.
 */
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
#define KASAN_SHADOW_OFFSET     _AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
#define KASAN_SHADOW_END        ((UL(1) << (64 - KASAN_SHADOW_SCALE_SHIFT)) + KASAN_SHADOW_OFFSET)
#define _KASAN_SHADOW_START(va) (KASAN_SHADOW_END - (UL(1) << ((va) - KASAN_SHADOW_SCALE_SHIFT)))
#define KASAN_SHADOW_START      _KASAN_SHADOW_START(vabits_actual)
#define PAGE_END                KASAN_SHADOW_START
#define KASAN_THREAD_SHIFT      1
#else
#define KASAN_THREAD_SHIFT      0
#define PAGE_END                (_PAGE_END(VA_BITS_MIN))
#endif /* CONFIG_KASAN */

#define DIRECT_MAP_PHYSMEM_END  __pa(PAGE_END - 1)

#define MIN_THREAD_SHIFT        (14 + KASAN_THREAD_SHIFT)

/*
 * VMAP'd stacks are allocated at page granularity, so we must ensure that such
 * stacks are a multiple of page size.
 */
#if (MIN_THREAD_SHIFT < PAGE_SHIFT)
#define THREAD_SHIFT            PAGE_SHIFT
#else
#define THREAD_SHIFT            MIN_THREAD_SHIFT
#endif

#if THREAD_SHIFT >= PAGE_SHIFT
#define THREAD_SIZE_ORDER       (THREAD_SHIFT - PAGE_SHIFT)
#endif

#define THREAD_SIZE             (UL(1) << THREAD_SHIFT)

/*
 * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
 * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
 * assembly.
 */
#define THREAD_ALIGN            (2 * THREAD_SIZE)

#define IRQ_STACK_SIZE          THREAD_SIZE

#define OVERFLOW_STACK_SIZE     SZ_4K

#define NVHE_STACK_SHIFT       PAGE_SHIFT
#define NVHE_STACK_SIZE        (UL(1) << NVHE_STACK_SHIFT)

/*
 * With the minimum frame size of [x29, x30], exactly half the combined
 * sizes of the hyp and overflow stacks is the maximum size needed to
 * save the unwinded stacktrace; plus an additional entry to delimit the
 * end.
 */
#define NVHE_STACKTRACE_SIZE    ((OVERFLOW_STACK_SIZE + NVHE_STACK_SIZE) / 2 + sizeof(long))

/*
 * Alignment of kernel segments (e.g. .text, .data).
 *
 *  4 KB granule:  16 level 3 entries, with contiguous bit
 * 16 KB granule:   4 level 3 entries, without contiguous bit
 * 64 KB granule:   1 level 3 entry
 */
#define SEGMENT_ALIGN           SZ_64K

/*
 * Memory types available.
 *
 * IMPORTANT: MT_NORMAL must be index 0 since vm_get_page_prot() may 'or' in
 *            the MT_NORMAL_TAGGED memory type for PROT_MTE mappings. Note
 *            that protection_map[] only contains MT_NORMAL attributes.
 */
#define MT_NORMAL               0
#define MT_NORMAL_TAGGED        1
#define MT_NORMAL_NC            2
#define MT_DEVICE_nGnRnE        3
#define MT_DEVICE_nGnRE         4

/*
 * Memory types for Stage-2 translation when HCR_EL2.FWB=0. See R_HMNDG,
 * R_TNHFM, R_GQFSF and I_MCQKW for the details on how these attributes get
 * combined with Stage-1.
 */
#define MT_S2_NORMAL            0xf
#define MT_S2_NORMAL_NC         0x5
#define MT_S2_DEVICE_nGnRE      0x1
#define MT_S2_AS_S1             MT_S2_NORMAL

/*
 * Memory types for Stage-2 translation when HCR_EL2.FWB=1. Stage-2 enforces
 * Normal-WB and Device-nGnRE, unless we actively say that S1 wins. See
 * R_VRJSW and R_RHWZM for details.
 */
#define MT_S2_FWB_NORMAL        6
#define MT_S2_FWB_NORMAL_NC     5
#define MT_S2_FWB_DEVICE_nGnRE  1
#define MT_S2_FWB_AS_S1         7

#ifdef CONFIG_ARM64_4K_PAGES
#define IOREMAP_MAX_ORDER       (PUD_SHIFT)
#else
#define IOREMAP_MAX_ORDER       (PMD_SHIFT)
#endif

/*
 *  Open-coded (swapper_pg_dir - reserved_pg_dir) as this cannot be calculated
 *  until link time.
 */
#define RESERVED_SWAPPER_OFFSET (PAGE_SIZE)

/*
 *  Open-coded (swapper_pg_dir - tramp_pg_dir) as this cannot be calculated
 *  until link time.
 */
#define TRAMP_SWAPPER_OFFSET    (2 * PAGE_SIZE)

#ifndef __ASSEMBLER__

#include <linux/bitops.h>
#include <linux/compiler.h>
#include <linux/mmdebug.h>
#include <linux/types.h>
#include <asm/boot.h>
#include <asm/bug.h>
#include <asm/sections.h>
#include <asm/sysreg.h>

static inline u64 __pure read_tcr(void)
{
        u64  tcr;

        // read_sysreg() uses asm volatile, so avoid it here
        asm("mrs %0, tcr_el1" : "=r"(tcr));
        return tcr;
}

#if VA_BITS > 48
// For reasons of #include hell, we can't use TCR_T1SZ_OFFSET/TCR_T1SZ_MASK here
#define vabits_actual           (64 - ((read_tcr() >> 16) & 63))
#else
#define vabits_actual           ((u64)VA_BITS)
#endif

extern s64                      memstart_addr;
/* PHYS_OFFSET - the physical address of the start of memory. */
#define PHYS_OFFSET             ({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })

/* the offset between the kernel virtual and physical mappings */
extern u64                      kimage_voffset;

static inline unsigned long kaslr_offset(void)
{
        return (u64)&_text - KIMAGE_VADDR;
}

#ifdef CONFIG_RANDOMIZE_BASE
void kaslr_init(void);
static inline bool kaslr_enabled(void)
{
        extern bool __kaslr_is_enabled;
        return __kaslr_is_enabled;
}
#else
static inline void kaslr_init(void) { }
static inline bool kaslr_enabled(void) { return false; }
#endif

/*
 * Allow all memory at the discovery stage. We will clip it later.
 */
#define MIN_MEMBLOCK_ADDR       0
#define MAX_MEMBLOCK_ADDR       U64_MAX

/*
 * PFNs are used to describe any physical page; this means
 * PFN 0 == physical address 0.
 *
 * This is the PFN of the first RAM page in the kernel
 * direct-mapped view.  We assume this is the first page
 * of RAM in the mem_map as well.
 */
#define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)

/*
 * When dealing with data aborts, watchpoints, or instruction traps we may end
 * up with a tagged userland pointer. Clear the tag to get a sane pointer to
 * pass on to access_ok(), for instance.
 */
#define __untagged_addr(addr)   \
        ((__force __typeof__(addr))sign_extend64((__force u64)(addr), 55))

#define untagged_addr(addr)     ({                                      \
        u64 __addr = (__force u64)(addr);                                       \
        __addr &= __untagged_addr(__addr);                              \
        (__force __typeof__(addr))__addr;                               \
})

#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
#define __tag_shifted(tag)      ((u64)(tag) << 56)
#define __tag_reset(addr)       __untagged_addr(addr)
#define __tag_get(addr)         (__u8)((u64)(addr) >> 56)
#else
#define __tag_shifted(tag)      0UL
#define __tag_reset(addr)       (addr)
#define __tag_get(addr)         0
#endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */

static inline const void *__tag_set(const void *addr, u8 tag)
{
        u64 __addr = (u64)addr & ~__tag_shifted(0xff);
        return (const void *)(__addr | __tag_shifted(tag));
}

#ifdef CONFIG_KASAN_HW_TAGS
#define arch_enable_tag_checks_sync()           mte_enable_kernel_sync()
#define arch_enable_tag_checks_async()          mte_enable_kernel_async()
#define arch_enable_tag_checks_asymm()          mte_enable_kernel_asymm()
#define arch_enable_tag_checks_write_only()     mte_enable_kernel_store_only()
#define arch_suppress_tag_checks_start()        mte_enable_tco()
#define arch_suppress_tag_checks_stop()         mte_disable_tco()
#define arch_force_async_tag_fault()            mte_check_tfsr_exit()
#define arch_get_random_tag()                   mte_get_random_tag()
#define arch_get_mem_tag(addr)                  mte_get_mem_tag(addr)
#define arch_set_mem_tag_range(addr, size, tag, init)   \
                        mte_set_mem_tag_range((addr), (size), (tag), (init))
#endif /* CONFIG_KASAN_HW_TAGS */

/*
 * Physical vs virtual RAM address space conversion.  These are
 * private definitions which should NOT be used outside memory.h
 * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
 */


/*
 * Check whether an arbitrary address is within the linear map, which
 * lives in the [PAGE_OFFSET, PAGE_END) interval at the bottom of the
 * kernel's TTBR1 address range.
 */
#define __is_lm_address(addr)   (((u64)(addr) - PAGE_OFFSET) < (PAGE_END - PAGE_OFFSET))

#define __lm_to_phys(addr)      (((addr) - PAGE_OFFSET) + PHYS_OFFSET)
#define __kimg_to_phys(addr)    ((addr) - kimage_voffset)

#define __virt_to_phys_nodebug(x) ({                                    \
        phys_addr_t __x = (phys_addr_t)(__tag_reset(x));                \
        __is_lm_address(__x) ? __lm_to_phys(__x) : __kimg_to_phys(__x); \
})

#define __pa_symbol_nodebug(x)  __kimg_to_phys((phys_addr_t)(x))

#ifdef CONFIG_DEBUG_VIRTUAL
extern phys_addr_t __virt_to_phys(unsigned long x);
extern phys_addr_t __phys_addr_symbol(unsigned long x);
#else
#define __virt_to_phys(x)       __virt_to_phys_nodebug(x)
#define __phys_addr_symbol(x)   __pa_symbol_nodebug(x)
#endif /* CONFIG_DEBUG_VIRTUAL */

#define __phys_to_virt(x)       ((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
#define __phys_to_kimg(x)       ((unsigned long)((x) + kimage_voffset))

/*
 * Note: Drivers should NOT use these.  They are the wrong
 * translation for translating DMA addresses.  Use the driver
 * DMA support - see dma-mapping.h.
 */
#define virt_to_phys virt_to_phys
static inline phys_addr_t virt_to_phys(const volatile void *x)
{
        return __virt_to_phys((unsigned long)(x));
}

#define phys_to_virt phys_to_virt
static inline void *phys_to_virt(phys_addr_t x)
{
        return (void *)(__phys_to_virt(x));
}

/* Needed already here for resolving __phys_to_pfn() in virt_to_pfn() */
#include <asm-generic/memory_model.h>

static inline unsigned long virt_to_pfn(const void *kaddr)
{
        return __phys_to_pfn(virt_to_phys(kaddr));
}

/*
 * Drivers should NOT use these either.
 */
#define __pa(x)                 __virt_to_phys((unsigned long)(x))
#define __pa_symbol(x)          __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
#define __pa_nodebug(x)         __virt_to_phys_nodebug((unsigned long)(x))
#define __va(x)                 ((void *)__phys_to_virt((phys_addr_t)(x)))
#define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
#define sym_to_pfn(x)           __phys_to_pfn(__pa_symbol(x))

/*
 *  virt_to_page(x)     convert a _valid_ virtual address to struct page *
 *  virt_addr_valid(x)  indicates whether a virtual address is valid
 */

#if defined(CONFIG_DEBUG_VIRTUAL)
#define page_to_virt(x) ({                                              \
        __typeof__(x) __page = x;                                       \
        void *__addr = __va(page_to_phys(__page));                      \
        (void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\
})
#define virt_to_page(x)         pfn_to_page(virt_to_pfn(x))
#else
#define page_to_virt(x) ({                                              \
        __typeof__(x) __page = x;                                       \
        u64 __idx = ((u64)__page - VMEMMAP_START) / sizeof(struct page);\
        u64 __addr = PAGE_OFFSET + (__idx * PAGE_SIZE);                 \
        (void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\
})

#define virt_to_page(x) ({                                              \
        u64 __idx = (__tag_reset((u64)x) - PAGE_OFFSET) / PAGE_SIZE;    \
        u64 __addr = VMEMMAP_START + (__idx * sizeof(struct page));     \
        (struct page *)__addr;                                          \
})
#endif /* CONFIG_DEBUG_VIRTUAL */

#define virt_addr_valid(addr)   ({                                      \
        __typeof__(addr) __addr = __tag_reset(addr);                    \
        __is_lm_address(__addr) && pfn_is_map_memory(virt_to_pfn(__addr));      \
})

void dump_mem_limit(void);
#endif /* !__ASSEMBLER__ */

/*
 * Given that the GIC architecture permits ITS implementations that can only be
 * configured with a LPI table address once, GICv3 systems with many CPUs may
 * end up reserving a lot of different regions after a kexec for their LPI
 * tables (one per CPU), as we are forced to reuse the same memory after kexec
 * (and thus reserve it persistently with EFI beforehand)
 */
#if defined(CONFIG_EFI) && defined(CONFIG_ARM_GIC_V3_ITS)
# define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CPUS + 1)
#endif

/*
 * memory regions which marked with flag MEMBLOCK_NOMAP(for example, the memory
 * of the EFI_UNUSABLE_MEMORY type) may divide a continuous memory block into
 * multiple parts. As a result, the number of memory regions is large.
 */
#ifdef CONFIG_EFI
#define INIT_MEMBLOCK_MEMORY_REGIONS    (INIT_MEMBLOCK_REGIONS * 8)
#endif


#endif /* __ASM_MEMORY_H */