From f7ae02333d13f598da6ff6b94cf643255707f752 Mon Sep 17 00:00:00 2001 From: Alexandre Ghiti Date: Mon, 6 Dec 2021 11:46:45 +0100 Subject: riscv: Move KASAN mapping next to the kernel mapping Now that KASAN_SHADOW_OFFSET is defined at compile time as a config, this value must remain constant whatever the size of the virtual address space, which is only possible by pushing this region at the end of the address space next to the kernel mapping. Signed-off-by: Alexandre Ghiti Signed-off-by: Palmer Dabbelt --- arch/riscv/include/asm/kasan.h | 4 ++-- arch/riscv/include/asm/page.h | 2 -- arch/riscv/include/asm/pgtable.h | 22 +++++++++++++++------- 3 files changed, 17 insertions(+), 11 deletions(-) (limited to 'arch/riscv/include/asm') diff --git a/arch/riscv/include/asm/kasan.h b/arch/riscv/include/asm/kasan.h index b00f503ec124..257a2495145a 100644 --- a/arch/riscv/include/asm/kasan.h +++ b/arch/riscv/include/asm/kasan.h @@ -28,8 +28,8 @@ #define KASAN_SHADOW_SCALE_SHIFT 3 #define KASAN_SHADOW_SIZE (UL(1) << ((CONFIG_VA_BITS - 1) - KASAN_SHADOW_SCALE_SHIFT)) -#define KASAN_SHADOW_START KERN_VIRT_START -#define KASAN_SHADOW_END (KASAN_SHADOW_START + KASAN_SHADOW_SIZE) +#define KASAN_SHADOW_START (KASAN_SHADOW_END - KASAN_SHADOW_SIZE) +#define KASAN_SHADOW_END MODULES_LOWEST_VADDR #define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL) void kasan_init(void); diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h index b3e5ff0125fe..a18c989e600c 100644 --- a/arch/riscv/include/asm/page.h +++ b/arch/riscv/include/asm/page.h @@ -33,8 +33,6 @@ */ #define PAGE_OFFSET _AC(CONFIG_PAGE_OFFSET, UL) -#define KERN_VIRT_SIZE (-PAGE_OFFSET) - #ifndef __ASSEMBLY__ #define clear_page(pgaddr) memset((pgaddr), 0, PAGE_SIZE) diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index bf204e7c1f74..fa400b2abb36 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -24,6 +24,17 @@ #define KERNEL_LINK_ADDR PAGE_OFFSET #endif +/* Number of entries in the page global directory */ +#define PTRS_PER_PGD (PAGE_SIZE / sizeof(pgd_t)) +/* Number of entries in the page table */ +#define PTRS_PER_PTE (PAGE_SIZE / sizeof(pte_t)) + +/* + * Half of the kernel address space (half of the entries of the page global + * directory) is for the direct mapping. + */ +#define KERN_VIRT_SIZE ((PTRS_PER_PGD / 2 * PGDIR_SIZE) / 2) + #define VMALLOC_SIZE (KERN_VIRT_SIZE >> 1) #define VMALLOC_END (PAGE_OFFSET - 1) #define VMALLOC_START (PAGE_OFFSET - VMALLOC_SIZE) @@ -39,8 +50,10 @@ /* Modules always live before the kernel */ #ifdef CONFIG_64BIT -#define MODULES_VADDR (PFN_ALIGN((unsigned long)&_end) - SZ_2G) -#define MODULES_END (PFN_ALIGN((unsigned long)&_start)) +/* This is used to define the end of the KASAN shadow region */ +#define MODULES_LOWEST_VADDR (KERNEL_LINK_ADDR - SZ_2G) +#define MODULES_VADDR (PFN_ALIGN((unsigned long)&_end) - SZ_2G) +#define MODULES_END (PFN_ALIGN((unsigned long)&_start)) #endif /* @@ -108,11 +121,6 @@ #endif /* CONFIG_XIP_KERNEL */ #ifdef CONFIG_MMU -/* Number of entries in the page global directory */ -#define PTRS_PER_PGD (PAGE_SIZE / sizeof(pgd_t)) -/* Number of entries in the page table */ -#define PTRS_PER_PTE (PAGE_SIZE / sizeof(pte_t)) - /* Number of PGD entries that a user-mode program can use */ #define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE) -- cgit v1.2.3 From 2efad17e5794f4223bbeff1b2c568e3afd9a8c22 Mon Sep 17 00:00:00 2001 From: Alexandre Ghiti Date: Mon, 6 Dec 2021 11:46:46 +0100 Subject: riscv: Split early kasan mapping to prepare sv48 introduction Now that kasan shadow region is next to the kernel, for sv48, this region won't be aligned on PGDIR_SIZE and then when populating this region, we'll need to get down to lower levels of the page table. So instead of reimplementing the page table walk for the early population, take advantage of the existing functions used for the final population. Note that kasan swapper initialization must also be split since memblock is not initialized at this point and as the last PGD is shared with the kernel, we'd need to allocate a PUD so postpone the kasan final population after the kernel population is done. Signed-off-by: Alexandre Ghiti Signed-off-by: Palmer Dabbelt --- arch/riscv/include/asm/kasan.h | 1 + arch/riscv/mm/init.c | 4 ++ arch/riscv/mm/kasan_init.c | 113 ++++++++++++++++++++++------------------- 3 files changed, 67 insertions(+), 51 deletions(-) (limited to 'arch/riscv/include/asm') diff --git a/arch/riscv/include/asm/kasan.h b/arch/riscv/include/asm/kasan.h index 257a2495145a..2788e2c46609 100644 --- a/arch/riscv/include/asm/kasan.h +++ b/arch/riscv/include/asm/kasan.h @@ -34,6 +34,7 @@ void kasan_init(void); asmlinkage void kasan_early_init(void); +void kasan_swapper_init(void); #endif #endif diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index f515964e9c00..f5d0052c95ad 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -741,6 +741,10 @@ static void __init setup_vm_final(void) create_kernel_page_table(swapper_pg_dir, false); #endif +#ifdef CONFIG_KASAN + kasan_swapper_init(); +#endif + /* Clear fixmap PTE and PMD mappings */ clear_fixmap(FIX_PTE); clear_fixmap(FIX_PMD); diff --git a/arch/riscv/mm/kasan_init.c b/arch/riscv/mm/kasan_init.c index 54294f83513d..1434a0225140 100644 --- a/arch/riscv/mm/kasan_init.c +++ b/arch/riscv/mm/kasan_init.c @@ -12,44 +12,6 @@ #include extern pgd_t early_pg_dir[PTRS_PER_PGD]; -asmlinkage void __init kasan_early_init(void) -{ - uintptr_t i; - pgd_t *pgd = early_pg_dir + pgd_index(KASAN_SHADOW_START); - - BUILD_BUG_ON(KASAN_SHADOW_OFFSET != - KASAN_SHADOW_END - (1UL << (64 - KASAN_SHADOW_SCALE_SHIFT))); - - for (i = 0; i < PTRS_PER_PTE; ++i) - set_pte(kasan_early_shadow_pte + i, - mk_pte(virt_to_page(kasan_early_shadow_page), - PAGE_KERNEL)); - - for (i = 0; i < PTRS_PER_PMD; ++i) - set_pmd(kasan_early_shadow_pmd + i, - pfn_pmd(PFN_DOWN - (__pa((uintptr_t) kasan_early_shadow_pte)), - __pgprot(_PAGE_TABLE))); - - for (i = KASAN_SHADOW_START; i < KASAN_SHADOW_END; - i += PGDIR_SIZE, ++pgd) - set_pgd(pgd, - pfn_pgd(PFN_DOWN - (__pa(((uintptr_t) kasan_early_shadow_pmd))), - __pgprot(_PAGE_TABLE))); - - /* init for swapper_pg_dir */ - pgd = pgd_offset_k(KASAN_SHADOW_START); - - for (i = KASAN_SHADOW_START; i < KASAN_SHADOW_END; - i += PGDIR_SIZE, ++pgd) - set_pgd(pgd, - pfn_pgd(PFN_DOWN - (__pa(((uintptr_t) kasan_early_shadow_pmd))), - __pgprot(_PAGE_TABLE))); - - local_flush_tlb_all(); -} static void __init kasan_populate_pte(pmd_t *pmd, unsigned long vaddr, unsigned long end) { @@ -108,26 +70,35 @@ static void __init kasan_populate_pmd(pgd_t *pgd, unsigned long vaddr, unsigned set_pgd(pgd, pfn_pgd(PFN_DOWN(__pa(base_pmd)), PAGE_TABLE)); } -static void __init kasan_populate_pgd(unsigned long vaddr, unsigned long end) +static void __init kasan_populate_pgd(pgd_t *pgdp, + unsigned long vaddr, unsigned long end, + bool early) { phys_addr_t phys_addr; - pgd_t *pgdp = pgd_offset_k(vaddr); unsigned long next; do { next = pgd_addr_end(vaddr, end); - /* - * pgdp can't be none since kasan_early_init initialized all KASAN - * shadow region with kasan_early_shadow_pmd: if this is stillthe case, - * that means we can try to allocate a hugepage as a replacement. - */ - if (pgd_page_vaddr(*pgdp) == (unsigned long)lm_alias(kasan_early_shadow_pmd) && - IS_ALIGNED(vaddr, PGDIR_SIZE) && (next - vaddr) >= PGDIR_SIZE) { - phys_addr = memblock_phys_alloc(PGDIR_SIZE, PGDIR_SIZE); - if (phys_addr) { - set_pgd(pgdp, pfn_pgd(PFN_DOWN(phys_addr), PAGE_KERNEL)); + if (IS_ALIGNED(vaddr, PGDIR_SIZE) && (next - vaddr) >= PGDIR_SIZE) { + if (early) { + phys_addr = __pa((uintptr_t)kasan_early_shadow_pgd_next); + set_pgd(pgdp, pfn_pgd(PFN_DOWN(phys_addr), PAGE_TABLE)); continue; + } else if (pgd_page_vaddr(*pgdp) == + (unsigned long)lm_alias(kasan_early_shadow_pgd_next)) { + /* + * pgdp can't be none since kasan_early_init + * initialized all KASAN shadow region with + * kasan_early_shadow_pud: if this is still the + * case, that means we can try to allocate a + * hugepage as a replacement. + */ + phys_addr = memblock_phys_alloc(PGDIR_SIZE, PGDIR_SIZE); + if (phys_addr) { + set_pgd(pgdp, pfn_pgd(PFN_DOWN(phys_addr), PAGE_KERNEL)); + continue; + } } } @@ -135,12 +106,52 @@ static void __init kasan_populate_pgd(unsigned long vaddr, unsigned long end) } while (pgdp++, vaddr = next, vaddr != end); } +asmlinkage void __init kasan_early_init(void) +{ + uintptr_t i; + + BUILD_BUG_ON(KASAN_SHADOW_OFFSET != + KASAN_SHADOW_END - (1UL << (64 - KASAN_SHADOW_SCALE_SHIFT))); + + for (i = 0; i < PTRS_PER_PTE; ++i) + set_pte(kasan_early_shadow_pte + i, + mk_pte(virt_to_page(kasan_early_shadow_page), + PAGE_KERNEL)); + + for (i = 0; i < PTRS_PER_PMD; ++i) + set_pmd(kasan_early_shadow_pmd + i, + pfn_pmd(PFN_DOWN + (__pa((uintptr_t)kasan_early_shadow_pte)), + PAGE_TABLE)); + + if (pgtable_l4_enabled) { + for (i = 0; i < PTRS_PER_PUD; ++i) + set_pud(kasan_early_shadow_pud + i, + pfn_pud(PFN_DOWN + (__pa(((uintptr_t)kasan_early_shadow_pmd))), + PAGE_TABLE)); + } + + kasan_populate_pgd(early_pg_dir + pgd_index(KASAN_SHADOW_START), + KASAN_SHADOW_START, KASAN_SHADOW_END, true); + + local_flush_tlb_all(); +} + +void __init kasan_swapper_init(void) +{ + kasan_populate_pgd(pgd_offset_k(KASAN_SHADOW_START), + KASAN_SHADOW_START, KASAN_SHADOW_END, true); + + local_flush_tlb_all(); +} + static void __init kasan_populate(void *start, void *end) { unsigned long vaddr = (unsigned long)start & PAGE_MASK; unsigned long vend = PAGE_ALIGN((unsigned long)end); - kasan_populate_pgd(vaddr, vend); + kasan_populate_pgd(pgd_offset_k(vaddr), vaddr, vend, false); local_flush_tlb_all(); memset(start, KASAN_SHADOW_INIT, end - start); -- cgit v1.2.3 From 3270bfdb9e4a01bb15d018612a6354c1837b5f97 Mon Sep 17 00:00:00 2001 From: Alexandre Ghiti Date: Mon, 6 Dec 2021 11:46:48 +0100 Subject: riscv: Allow to dynamically define VA_BITS With 4-level page table folding at runtime, we don't know at compile time the size of the virtual address space so we must set VA_BITS dynamically so that sparsemem reserves the right amount of memory for struct pages. Signed-off-by: Alexandre Ghiti Signed-off-by: Palmer Dabbelt --- arch/riscv/Kconfig | 10 ---------- arch/riscv/include/asm/kasan.h | 2 +- arch/riscv/include/asm/pgtable.h | 10 ++++++++-- arch/riscv/include/asm/sparsemem.h | 6 +++++- 4 files changed, 14 insertions(+), 14 deletions(-) (limited to 'arch/riscv/include/asm') diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 7f8aea333291..7945bacb1d0e 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -146,16 +146,6 @@ config MMU Select if you want MMU-based virtualised addressing space support by paged memory management. If unsure, say 'Y'. -config VA_BITS - int - default 32 if 32BIT - default 39 if 64BIT - -config PA_BITS - int - default 34 if 32BIT - default 56 if 64BIT - config PAGE_OFFSET hex default 0xC0000000 if 32BIT diff --git a/arch/riscv/include/asm/kasan.h b/arch/riscv/include/asm/kasan.h index 2788e2c46609..743e6ff57996 100644 --- a/arch/riscv/include/asm/kasan.h +++ b/arch/riscv/include/asm/kasan.h @@ -27,7 +27,7 @@ */ #define KASAN_SHADOW_SCALE_SHIFT 3 -#define KASAN_SHADOW_SIZE (UL(1) << ((CONFIG_VA_BITS - 1) - KASAN_SHADOW_SCALE_SHIFT)) +#define KASAN_SHADOW_SIZE (UL(1) << ((VA_BITS - 1) - KASAN_SHADOW_SCALE_SHIFT)) #define KASAN_SHADOW_START (KASAN_SHADOW_END - KASAN_SHADOW_SIZE) #define KASAN_SHADOW_END MODULES_LOWEST_VADDR #define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL) diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index fa400b2abb36..23c7c66f2d79 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -61,8 +61,14 @@ * struct pages to map half the virtual address space. Then * position vmemmap directly below the VMALLOC region. */ +#ifdef CONFIG_64BIT +#define VA_BITS 39 +#else +#define VA_BITS 32 +#endif + #define VMEMMAP_SHIFT \ - (CONFIG_VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT) + (VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT) #define VMEMMAP_SIZE BIT(VMEMMAP_SHIFT) #define VMEMMAP_END (VMALLOC_START - 1) #define VMEMMAP_START (VMALLOC_START - VMEMMAP_SIZE) @@ -661,7 +667,7 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma, * and give the kernel the other (upper) half. */ #ifdef CONFIG_64BIT -#define KERN_VIRT_START (-(BIT(CONFIG_VA_BITS)) + TASK_SIZE) +#define KERN_VIRT_START (-(BIT(VA_BITS)) + TASK_SIZE) #else #define KERN_VIRT_START FIXADDR_START #endif diff --git a/arch/riscv/include/asm/sparsemem.h b/arch/riscv/include/asm/sparsemem.h index 45a7018a8118..63acaecc3374 100644 --- a/arch/riscv/include/asm/sparsemem.h +++ b/arch/riscv/include/asm/sparsemem.h @@ -4,7 +4,11 @@ #define _ASM_RISCV_SPARSEMEM_H #ifdef CONFIG_SPARSEMEM -#define MAX_PHYSMEM_BITS CONFIG_PA_BITS +#ifdef CONFIG_64BIT +#define MAX_PHYSMEM_BITS 56 +#else +#define MAX_PHYSMEM_BITS 34 +#endif /* CONFIG_64BIT */ #define SECTION_SIZE_BITS 27 #endif /* CONFIG_SPARSEMEM */ -- cgit v1.2.3 From e8a62cc26ddf53a3c6ba2a8d33036cf7b84f3923 Mon Sep 17 00:00:00 2001 From: Alexandre Ghiti Date: Mon, 6 Dec 2021 11:46:51 +0100 Subject: riscv: Implement sv48 support By adding a new 4th level of page table, give the possibility to 64bit kernel to address 2^48 bytes of virtual address: in practice, that offers 128TB of virtual address space to userspace and allows up to 64TB of physical memory. If the underlying hardware does not support sv48, we will automatically fallback to a standard 3-level page table by folding the new PUD level into PGDIR level. In order to detect HW capabilities at runtime, we use SATP feature that ignores writes with an unsupported mode. Signed-off-by: Alexandre Ghiti Signed-off-by: Palmer Dabbelt --- arch/riscv/Kconfig | 4 +- arch/riscv/include/asm/csr.h | 3 +- arch/riscv/include/asm/fixmap.h | 1 + arch/riscv/include/asm/kasan.h | 6 +- arch/riscv/include/asm/page.h | 14 +++ arch/riscv/include/asm/pgalloc.h | 40 ++++++ arch/riscv/include/asm/pgtable-64.h | 108 +++++++++++++++- arch/riscv/include/asm/pgtable.h | 24 +++- arch/riscv/kernel/head.S | 3 +- arch/riscv/mm/context.c | 4 +- arch/riscv/mm/init.c | 212 ++++++++++++++++++++++++++++---- arch/riscv/mm/kasan_init.c | 137 ++++++++++++++++++++- drivers/firmware/efi/libstub/efi-stub.c | 2 + 13 files changed, 514 insertions(+), 44 deletions(-) (limited to 'arch/riscv/include/asm') diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 7945bacb1d0e..c4289d755dd4 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -150,7 +150,7 @@ config PAGE_OFFSET hex default 0xC0000000 if 32BIT default 0x80000000 if 64BIT && !MMU - default 0xffffffd800000000 if 64BIT + default 0xffffaf8000000000 if 64BIT config KASAN_SHADOW_OFFSET hex @@ -201,7 +201,7 @@ config FIX_EARLYCON_MEM config PGTABLE_LEVELS int - default 3 if 64BIT + default 4 if 64BIT default 2 config LOCKDEP_SUPPORT diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h index 5046f431645c..ae711692eec9 100644 --- a/arch/riscv/include/asm/csr.h +++ b/arch/riscv/include/asm/csr.h @@ -40,14 +40,13 @@ #ifndef CONFIG_64BIT #define SATP_PPN _AC(0x003FFFFF, UL) #define SATP_MODE_32 _AC(0x80000000, UL) -#define SATP_MODE SATP_MODE_32 #define SATP_ASID_BITS 9 #define SATP_ASID_SHIFT 22 #define SATP_ASID_MASK _AC(0x1FF, UL) #else #define SATP_PPN _AC(0x00000FFFFFFFFFFF, UL) #define SATP_MODE_39 _AC(0x8000000000000000, UL) -#define SATP_MODE SATP_MODE_39 +#define SATP_MODE_48 _AC(0x9000000000000000, UL) #define SATP_ASID_BITS 16 #define SATP_ASID_SHIFT 44 #define SATP_ASID_MASK _AC(0xFFFF, UL) diff --git a/arch/riscv/include/asm/fixmap.h b/arch/riscv/include/asm/fixmap.h index 54cbf07fb4e9..58a718573ad6 100644 --- a/arch/riscv/include/asm/fixmap.h +++ b/arch/riscv/include/asm/fixmap.h @@ -24,6 +24,7 @@ enum fixed_addresses { FIX_HOLE, FIX_PTE, FIX_PMD, + FIX_PUD, FIX_TEXT_POKE1, FIX_TEXT_POKE0, FIX_EARLYCON_MEM_BASE, diff --git a/arch/riscv/include/asm/kasan.h b/arch/riscv/include/asm/kasan.h index 743e6ff57996..0b85e363e778 100644 --- a/arch/riscv/include/asm/kasan.h +++ b/arch/riscv/include/asm/kasan.h @@ -28,7 +28,11 @@ #define KASAN_SHADOW_SCALE_SHIFT 3 #define KASAN_SHADOW_SIZE (UL(1) << ((VA_BITS - 1) - KASAN_SHADOW_SCALE_SHIFT)) -#define KASAN_SHADOW_START (KASAN_SHADOW_END - KASAN_SHADOW_SIZE) +/* + * Depending on the size of the virtual address space, the region may not be + * aligned on PGDIR_SIZE, so force its alignment to ease its population. + */ +#define KASAN_SHADOW_START ((KASAN_SHADOW_END - KASAN_SHADOW_SIZE) & PGDIR_MASK) #define KASAN_SHADOW_END MODULES_LOWEST_VADDR #define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL) diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h index a18c989e600c..160e3a1e8f8b 100644 --- a/arch/riscv/include/asm/page.h +++ b/arch/riscv/include/asm/page.h @@ -31,7 +31,20 @@ * When not using MMU this corresponds to the first free page in * physical memory (aligned on a page boundary). */ +#ifdef CONFIG_64BIT +#ifdef CONFIG_MMU +#define PAGE_OFFSET kernel_map.page_offset +#else +#define PAGE_OFFSET _AC(CONFIG_PAGE_OFFSET, UL) +#endif +/* + * By default, CONFIG_PAGE_OFFSET value corresponds to SV48 address space so + * define the PAGE_OFFSET value for SV39. + */ +#define PAGE_OFFSET_L3 _AC(0xffffffd800000000, UL) +#else #define PAGE_OFFSET _AC(CONFIG_PAGE_OFFSET, UL) +#endif /* CONFIG_64BIT */ #ifndef __ASSEMBLY__ @@ -84,6 +97,7 @@ extern unsigned long riscv_pfn_base; #endif /* CONFIG_MMU */ struct kernel_mapping { + unsigned long page_offset; unsigned long virt_addr; uintptr_t phys_addr; uintptr_t size; diff --git a/arch/riscv/include/asm/pgalloc.h b/arch/riscv/include/asm/pgalloc.h index 0af6933a7100..11823004b87a 100644 --- a/arch/riscv/include/asm/pgalloc.h +++ b/arch/riscv/include/asm/pgalloc.h @@ -11,6 +11,8 @@ #include #ifdef CONFIG_MMU +#define __HAVE_ARCH_PUD_ALLOC_ONE +#define __HAVE_ARCH_PUD_FREE #include static inline void pmd_populate_kernel(struct mm_struct *mm, @@ -36,6 +38,44 @@ static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd) set_pud(pud, __pud((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE)); } + +static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud) +{ + if (pgtable_l4_enabled) { + unsigned long pfn = virt_to_pfn(pud); + + set_p4d(p4d, __p4d((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE)); + } +} + +static inline void p4d_populate_safe(struct mm_struct *mm, p4d_t *p4d, + pud_t *pud) +{ + if (pgtable_l4_enabled) { + unsigned long pfn = virt_to_pfn(pud); + + set_p4d_safe(p4d, + __p4d((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE)); + } +} + +#define pud_alloc_one pud_alloc_one +static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr) +{ + if (pgtable_l4_enabled) + return __pud_alloc_one(mm, addr); + + return NULL; +} + +#define pud_free pud_free +static inline void pud_free(struct mm_struct *mm, pud_t *pud) +{ + if (pgtable_l4_enabled) + __pud_free(mm, pud); +} + +#define __pud_free_tlb(tlb, pud, addr) pud_free((tlb)->mm, pud) #endif /* __PAGETABLE_PMD_FOLDED */ static inline pgd_t *pgd_alloc(struct mm_struct *mm) diff --git a/arch/riscv/include/asm/pgtable-64.h b/arch/riscv/include/asm/pgtable-64.h index 228261aa9628..bbbdd66e5e2f 100644 --- a/arch/riscv/include/asm/pgtable-64.h +++ b/arch/riscv/include/asm/pgtable-64.h @@ -8,16 +8,36 @@ #include -#define PGDIR_SHIFT 30 +extern bool pgtable_l4_enabled; + +#define PGDIR_SHIFT_L3 30 +#define PGDIR_SHIFT_L4 39 +#define PGDIR_SIZE_L3 (_AC(1, UL) << PGDIR_SHIFT_L3) + +#define PGDIR_SHIFT (pgtable_l4_enabled ? PGDIR_SHIFT_L4 : PGDIR_SHIFT_L3) /* Size of region mapped by a page global directory */ #define PGDIR_SIZE (_AC(1, UL) << PGDIR_SHIFT) #define PGDIR_MASK (~(PGDIR_SIZE - 1)) +/* pud is folded into pgd in case of 3-level page table */ +#define PUD_SHIFT 30 +#define PUD_SIZE (_AC(1, UL) << PUD_SHIFT) +#define PUD_MASK (~(PUD_SIZE - 1)) + #define PMD_SHIFT 21 /* Size of region mapped by a page middle directory */ #define PMD_SIZE (_AC(1, UL) << PMD_SHIFT) #define PMD_MASK (~(PMD_SIZE - 1)) +/* Page Upper Directory entry */ +typedef struct { + unsigned long pud; +} pud_t; + +#define pud_val(x) ((x).pud) +#define __pud(x) ((pud_t) { (x) }) +#define PTRS_PER_PUD (PAGE_SIZE / sizeof(pud_t)) + /* Page Middle Directory entry */ typedef struct { unsigned long pmd; @@ -59,6 +79,16 @@ static inline void pud_clear(pud_t *pudp) set_pud(pudp, __pud(0)); } +static inline pud_t pfn_pud(unsigned long pfn, pgprot_t prot) +{ + return __pud((pfn << _PAGE_PFN_SHIFT) | pgprot_val(prot)); +} + +static inline unsigned long _pud_pfn(pud_t pud) +{ + return pud_val(pud) >> _PAGE_PFN_SHIFT; +} + static inline pmd_t *pud_pgtable(pud_t pud) { return (pmd_t *)pfn_to_virt(pud_val(pud) >> _PAGE_PFN_SHIFT); @@ -69,6 +99,17 @@ static inline struct page *pud_page(pud_t pud) return pfn_to_page(pud_val(pud) >> _PAGE_PFN_SHIFT); } +#define mm_pud_folded mm_pud_folded +static inline bool mm_pud_folded(struct mm_struct *mm) +{ + if (pgtable_l4_enabled) + return false; + + return true; +} + +#define pmd_index(addr) (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)) + static inline pmd_t pfn_pmd(unsigned long pfn, pgprot_t prot) { return __pmd((pfn << _PAGE_PFN_SHIFT) | pgprot_val(prot)); @@ -84,4 +125,69 @@ static inline unsigned long _pmd_pfn(pmd_t pmd) #define pmd_ERROR(e) \ pr_err("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e)) +#define pud_ERROR(e) \ + pr_err("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e)) + +static inline void set_p4d(p4d_t *p4dp, p4d_t p4d) +{ + if (pgtable_l4_enabled) + *p4dp = p4d; + else + set_pud((pud_t *)p4dp, (pud_t){ p4d_val(p4d) }); +} + +static inline int p4d_none(p4d_t p4d) +{ + if (pgtable_l4_enabled) + return (p4d_val(p4d) == 0); + + return 0; +} + +static inline int p4d_present(p4d_t p4d) +{ + if (pgtable_l4_enabled) + return (p4d_val(p4d) & _PAGE_PRESENT); + + return 1; +} + +static inline int p4d_bad(p4d_t p4d) +{ + if (pgtable_l4_enabled) + return !p4d_present(p4d); + + return 0; +} + +static inline void p4d_clear(p4d_t *p4d) +{ + if (pgtable_l4_enabled) + set_p4d(p4d, __p4d(0)); +} + +static inline pud_t *p4d_pgtable(p4d_t p4d) +{ + if (pgtable_l4_enabled) + return (pud_t *)pfn_to_virt(p4d_val(p4d) >> _PAGE_PFN_SHIFT); + + return (pud_t *)pud_pgtable((pud_t) { p4d_val(p4d) }); +} + +static inline struct page *p4d_page(p4d_t p4d) +{ + return pfn_to_page(p4d_val(p4d) >> _PAGE_PFN_SHIFT); +} + +#define pud_index(addr) (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1)) + +#define pud_offset pud_offset +static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address) +{ + if (pgtable_l4_enabled) + return p4d_pgtable(*p4d) + pud_index(address); + + return (pud_t *)p4d; +} + #endif /* _ASM_RISCV_PGTABLE_64_H */ diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index 23c7c66f2d79..2ab6650d3926 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -62,7 +62,7 @@ * position vmemmap directly below the VMALLOC region. */ #ifdef CONFIG_64BIT -#define VA_BITS 39 +#define VA_BITS (pgtable_l4_enabled ? 48 : 39) #else #define VA_BITS 32 #endif @@ -102,8 +102,7 @@ #ifndef __ASSEMBLY__ -/* Page Upper Directory not used in RISC-V */ -#include +#include #include #include #include @@ -126,6 +125,17 @@ #define XIP_FIXUP(addr) (addr) #endif /* CONFIG_XIP_KERNEL */ +struct pt_alloc_ops { + pte_t *(*get_pte_virt)(phys_addr_t pa); + phys_addr_t (*alloc_pte)(uintptr_t va); +#ifndef __PAGETABLE_PMD_FOLDED + pmd_t *(*get_pmd_virt)(phys_addr_t pa); + phys_addr_t (*alloc_pmd)(uintptr_t va); + pud_t *(*get_pud_virt)(phys_addr_t pa); + phys_addr_t (*alloc_pud)(uintptr_t va); +#endif +}; + #ifdef CONFIG_MMU /* Number of PGD entries that a user-mode program can use */ #define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE) @@ -677,9 +687,11 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma, * Note that PGDIR_SIZE must evenly divide TASK_SIZE. */ #ifdef CONFIG_64BIT -#define TASK_SIZE (PGDIR_SIZE * PTRS_PER_PGD / 2) +#define TASK_SIZE (PGDIR_SIZE * PTRS_PER_PGD / 2) +#define TASK_SIZE_MIN (PGDIR_SIZE_L3 * PTRS_PER_PGD / 2) #else -#define TASK_SIZE FIXADDR_START +#define TASK_SIZE FIXADDR_START +#define TASK_SIZE_MIN TASK_SIZE #endif #else /* CONFIG_MMU */ @@ -705,6 +717,8 @@ extern uintptr_t _dtb_early_pa; #define dtb_early_va _dtb_early_va #define dtb_early_pa _dtb_early_pa #endif /* CONFIG_XIP_KERNEL */ +extern u64 satp_mode; +extern bool pgtable_l4_enabled; void paging_init(void); void misc_mem_init(void); diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S index f52f01ecbeea..10e718559960 100644 --- a/arch/riscv/kernel/head.S +++ b/arch/riscv/kernel/head.S @@ -105,7 +105,8 @@ relocate: /* Compute satp for kernel page tables, but don't load it yet */ srl a2, a0, PAGE_SHIFT - li a1, SATP_MODE + la a1, satp_mode + REG_L a1, 0(a1) or a2, a2, a1 /* diff --git a/arch/riscv/mm/context.c b/arch/riscv/mm/context.c index ea54cc0c9106..7acbfbd14557 100644 --- a/arch/riscv/mm/context.c +++ b/arch/riscv/mm/context.c @@ -192,7 +192,7 @@ static void set_mm_asid(struct mm_struct *mm, unsigned int cpu) switch_mm_fast: csr_write(CSR_SATP, virt_to_pfn(mm->pgd) | ((cntx & asid_mask) << SATP_ASID_SHIFT) | - SATP_MODE); + satp_mode); if (need_flush_tlb) local_flush_tlb_all(); @@ -201,7 +201,7 @@ switch_mm_fast: static void set_mm_noasid(struct mm_struct *mm) { /* Switch the page table and blindly nuke entire local TLB */ - csr_write(CSR_SATP, virt_to_pfn(mm->pgd) | SATP_MODE); + csr_write(CSR_SATP, virt_to_pfn(mm->pgd) | satp_mode); local_flush_tlb_all(); } diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 424d7777f4df..7ba915849817 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -37,6 +37,17 @@ EXPORT_SYMBOL(kernel_map); #define kernel_map (*(struct kernel_mapping *)XIP_FIXUP(&kernel_map)) #endif +#ifdef CONFIG_64BIT +u64 satp_mode = !IS_ENABLED(CONFIG_XIP_KERNEL) ? SATP_MODE_48 : SATP_MODE_39; +#else +u64 satp_mode = SATP_MODE_32; +#endif +EXPORT_SYMBOL(satp_mode); + +bool pgtable_l4_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL) ? + true : false; +EXPORT_SYMBOL(pgtable_l4_enabled); + phys_addr_t phys_ram_base __ro_after_init; EXPORT_SYMBOL(phys_ram_base); @@ -53,15 +64,6 @@ extern char _start[]; void *_dtb_early_va __initdata; uintptr_t _dtb_early_pa __initdata; -struct pt_alloc_ops { - pte_t *(*get_pte_virt)(phys_addr_t pa); - phys_addr_t (*alloc_pte)(uintptr_t va); -#ifndef __PAGETABLE_PMD_FOLDED - pmd_t *(*get_pmd_virt)(phys_addr_t pa); - phys_addr_t (*alloc_pmd)(uintptr_t va); -#endif -}; - static phys_addr_t dma32_phys_limit __initdata; static void __init zone_sizes_init(void) @@ -222,7 +224,7 @@ static void __init setup_bootmem(void) } #ifdef CONFIG_MMU -static struct pt_alloc_ops _pt_ops __initdata; +struct pt_alloc_ops _pt_ops __initdata; #ifdef CONFIG_XIP_KERNEL #define pt_ops (*(struct pt_alloc_ops *)XIP_FIXUP(&_pt_ops)) @@ -238,6 +240,7 @@ pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss; static pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss; pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); +static pud_t __maybe_unused early_dtb_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE); static pmd_t __maybe_unused early_dtb_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE); #ifdef CONFIG_XIP_KERNEL @@ -326,6 +329,16 @@ static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE); #define early_pmd ((pmd_t *)XIP_FIXUP(early_pmd)) #endif /* CONFIG_XIP_KERNEL */ +static pud_t trampoline_pud[PTRS_PER_PUD] __page_aligned_bss; +static pud_t fixmap_pud[PTRS_PER_PUD] __page_aligned_bss; +static pud_t early_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE); + +#ifdef CONFIG_XIP_KERNEL +#define trampoline_pud ((pud_t *)XIP_FIXUP(trampoline_pud)) +#define fixmap_pud ((pud_t *)XIP_FIXUP(fixmap_pud)) +#define early_pud ((pud_t *)XIP_FIXUP(early_pud)) +#endif /* CONFIG_XIP_KERNEL */ + static pmd_t *__init get_pmd_virt_early(phys_addr_t pa) { /* Before MMU is enabled */ @@ -345,7 +358,7 @@ static pmd_t *__init get_pmd_virt_late(phys_addr_t pa) static phys_addr_t __init alloc_pmd_early(uintptr_t va) { - BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT); + BUG_ON((va - kernel_map.virt_addr) >> PUD_SHIFT); return (uintptr_t)early_pmd; } @@ -391,21 +404,97 @@ static void __init create_pmd_mapping(pmd_t *pmdp, create_pte_mapping(ptep, va, pa, sz, prot); } -#define pgd_next_t pmd_t -#define alloc_pgd_next(__va) pt_ops.alloc_pmd(__va) -#define get_pgd_next_virt(__pa) pt_ops.get_pmd_virt(__pa) +static pud_t *__init get_pud_virt_early(phys_addr_t pa) +{ + return (pud_t *)((uintptr_t)pa); +} + +static pud_t *__init get_pud_virt_fixmap(phys_addr_t pa) +{ + clear_fixmap(FIX_PUD); + return (pud_t *)set_fixmap_offset(FIX_PUD, pa); +} + +static pud_t *__init get_pud_virt_late(phys_addr_t pa) +{ + return (pud_t *)__va(pa); +} + +static phys_addr_t __init alloc_pud_early(uintptr_t va) +{ + /* Only one PUD is available for early mapping */ + BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT); + + return (uintptr_t)early_pud; +} + +static phys_addr_t __init alloc_pud_fixmap(uintptr_t va) +{ + return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); +} + +static phys_addr_t alloc_pud_late(uintptr_t va) +{ + unsigned long vaddr; + + vaddr = __get_free_page(GFP_KERNEL); + BUG_ON(!vaddr); + return __pa(vaddr); +} + +static void __init create_pud_mapping(pud_t *pudp, + uintptr_t va, phys_addr_t pa, + phys_addr_t sz, pgprot_t prot) +{ + pmd_t *nextp; + phys_addr_t next_phys; + uintptr_t pud_index = pud_index(va); + + if (sz == PUD_SIZE) { + if (pud_val(pudp[pud_index]) == 0) + pudp[pud_index] = pfn_pud(PFN_DOWN(pa), prot); + return; + } + + if (pud_val(pudp[pud_index]) == 0) { + next_phys = pt_ops.alloc_pmd(va); + pudp[pud_index] = pfn_pud(PFN_DOWN(next_phys), PAGE_TABLE); + nextp = pt_ops.get_pmd_virt(next_phys); + memset(nextp, 0, PAGE_SIZE); + } else { + next_phys = PFN_PHYS(_pud_pfn(pudp[pud_index])); + nextp = pt_ops.get_pmd_virt(next_phys); + } + + create_pmd_mapping(nextp, va, pa, sz, prot); +} + +#define pgd_next_t pud_t +#define alloc_pgd_next(__va) (pgtable_l4_enabled ? \ + pt_ops.alloc_pud(__va) : pt_ops.alloc_pmd(__va)) +#define get_pgd_next_virt(__pa) (pgtable_l4_enabled ? \ + pt_ops.get_pud_virt(__pa) : (pgd_next_t *)pt_ops.get_pmd_virt(__pa)) #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \ - create_pmd_mapping(__nextp, __va, __pa, __sz, __prot) -#define fixmap_pgd_next fixmap_pmd + (pgtable_l4_enabled ? \ + create_pud_mapping(__nextp, __va, __pa, __sz, __prot) : \ + create_pmd_mapping((pmd_t *)__nextp, __va, __pa, __sz, __prot)) +#define fixmap_pgd_next (pgtable_l4_enabled ? \ + (uintptr_t)fixmap_pud : (uintptr_t)fixmap_pmd) +#define trampoline_pgd_next (pgtable_l4_enabled ? \ + (uintptr_t)trampoline_pud : (uintptr_t)trampoline_pmd) +#define early_dtb_pgd_next (pgtable_l4_enabled ? \ + (uintptr_t)early_dtb_pud : (uintptr_t)early_dtb_pmd) #else #define pgd_next_t pte_t #define alloc_pgd_next(__va) pt_ops.alloc_pte(__va) #define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa) #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \ create_pte_mapping(__nextp, __va, __pa, __sz, __prot) -#define fixmap_pgd_next fixmap_pte +#define fixmap_pgd_next ((uintptr_t)fixmap_pte) +#define early_dtb_pgd_next ((uintptr_t)early_dtb_pmd) +#define create_pud_mapping(__pmdp, __va, __pa, __sz, __prot) #define create_pmd_mapping(__pmdp, __va, __pa, __sz, __prot) -#endif +#endif /* __PAGETABLE_PMD_FOLDED */ void __init create_pgd_mapping(pgd_t *pgdp, uintptr_t va, phys_addr_t pa, @@ -492,6 +581,57 @@ static __init pgprot_t pgprot_from_va(uintptr_t va) } #endif /* CONFIG_STRICT_KERNEL_RWX */ +#ifdef CONFIG_64BIT +static void __init disable_pgtable_l4(void) +{ + pgtable_l4_enabled = false; + kernel_map.page_offset = PAGE_OFFSET_L3; + satp_mode = SATP_MODE_39; +} + +/* + * There is a simple way to determine if 4-level is supported by the + * underlying hardware: establish 1:1 mapping in 4-level page table mode + * then read SATP to see if the configuration was taken into account + * meaning sv48 is supported. + */ +static __init void set_satp_mode(void) +{ + u64 identity_satp, hw_satp; + uintptr_t set_satp_mode_pmd; + + set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK; + create_pgd_mapping(early_pg_dir, + set_satp_mode_pmd, (uintptr_t)early_pud, + PGDIR_SIZE, PAGE_TABLE); + create_pud_mapping(early_pud, + set_satp_mode_pmd, (uintptr_t)early_pmd, + PUD_SIZE, PAGE_TABLE); + /* Handle the case where set_satp_mode straddles 2 PMDs */ + create_pmd_mapping(early_pmd, + set_satp_mode_pmd, set_satp_mode_pmd, + PMD_SIZE, PAGE_KERNEL_EXEC); + create_pmd_mapping(early_pmd, + set_satp_mode_pmd + PMD_SIZE, + set_satp_mode_pmd + PMD_SIZE, + PMD_SIZE, PAGE_KERNEL_EXEC); + + identity_satp = PFN_DOWN((uintptr_t)&early_pg_dir) | satp_mode; + + local_flush_tlb_all(); + csr_write(CSR_SATP, identity_satp); + hw_satp = csr_swap(CSR_SATP, 0ULL); + local_flush_tlb_all(); + + if (hw_satp != identity_satp) + disable_pgtable_l4(); + + memset(early_pg_dir, 0, PAGE_SIZE); + memset(early_pud, 0, PAGE_SIZE); + memset(early_pmd, 0, PAGE_SIZE); +} +#endif + /* * setup_vm() is called from head.S with MMU-off. * @@ -556,10 +696,15 @@ static void __init create_fdt_early_page_table(pgd_t *pgdir, uintptr_t dtb_pa) uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1); create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA, - IS_ENABLED(CONFIG_64BIT) ? (uintptr_t)early_dtb_pmd : pa, + IS_ENABLED(CONFIG_64BIT) ? early_dtb_pgd_next : pa, PGDIR_SIZE, IS_ENABLED(CONFIG_64BIT) ? PAGE_TABLE : PAGE_KERNEL); + if (pgtable_l4_enabled) { + create_pud_mapping(early_dtb_pud, DTB_EARLY_BASE_VA, + (uintptr_t)early_dtb_pmd, PUD_SIZE, PAGE_TABLE); + } + if (IS_ENABLED(CONFIG_64BIT)) { create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA, pa, PMD_SIZE, PAGE_KERNEL); @@ -592,6 +737,8 @@ void pt_ops_set_early(void) #ifndef __PAGETABLE_PMD_FOLDED pt_ops.alloc_pmd = alloc_pmd_early; pt_ops.get_pmd_virt = get_pmd_virt_early; + pt_ops.alloc_pud = alloc_pud_early; + pt_ops.get_pud_virt = get_pud_virt_early; #endif } @@ -610,6 +757,8 @@ void pt_ops_set_fixmap(void) #ifndef __PAGETABLE_PMD_FOLDED pt_ops.alloc_pmd = kernel_mapping_pa_to_va((uintptr_t)alloc_pmd_fixmap); pt_ops.get_pmd_virt = kernel_mapping_pa_to_va((uintptr_t)get_pmd_virt_fixmap); + pt_ops.alloc_pud = kernel_mapping_pa_to_va((uintptr_t)alloc_pud_fixmap); + pt_ops.get_pud_virt = kernel_mapping_pa_to_va((uintptr_t)get_pud_virt_fixmap); #endif } @@ -624,6 +773,8 @@ void pt_ops_set_late(void) #ifndef __PAGETABLE_PMD_FOLDED pt_ops.alloc_pmd = alloc_pmd_late; pt_ops.get_pmd_virt = get_pmd_virt_late; + pt_ops.alloc_pud = alloc_pud_late; + pt_ops.get_pud_virt = get_pud_virt_late; #endif } @@ -632,6 +783,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) pmd_t __maybe_unused fix_bmap_spmd, fix_bmap_epmd; kernel_map.virt_addr = KERNEL_LINK_ADDR; + kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL); #ifdef CONFIG_XIP_KERNEL kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR; @@ -646,6 +798,11 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) kernel_map.phys_addr = (uintptr_t)(&_start); kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr; #endif + +#if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL) + set_satp_mode(); +#endif + kernel_map.va_pa_offset = PAGE_OFFSET - kernel_map.phys_addr; kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr; @@ -675,15 +832,21 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) /* Setup early PGD for fixmap */ create_pgd_mapping(early_pg_dir, FIXADDR_START, - (uintptr_t)fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE); + fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE); #ifndef __PAGETABLE_PMD_FOLDED - /* Setup fixmap PMD */ + /* Setup fixmap PUD and PMD */ + if (pgtable_l4_enabled) + create_pud_mapping(fixmap_pud, FIXADDR_START, + (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE); create_pmd_mapping(fixmap_pmd, FIXADDR_START, (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE); /* Setup trampoline PGD and PMD */ create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr, - (uintptr_t)trampoline_pmd, PGDIR_SIZE, PAGE_TABLE); + trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE); + if (pgtable_l4_enabled) + create_pud_mapping(trampoline_pud, kernel_map.virt_addr, + (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE); #ifdef CONFIG_XIP_KERNEL create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr, kernel_map.xiprom, PMD_SIZE, PAGE_KERNEL_EXEC); @@ -711,7 +874,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap * range can not span multiple pmds. */ - BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT) + BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT) != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT)); #ifndef __PAGETABLE_PMD_FOLDED @@ -782,9 +945,10 @@ static void __init setup_vm_final(void) /* Clear fixmap PTE and PMD mappings */ clear_fixmap(FIX_PTE); clear_fixmap(FIX_PMD); + clear_fixmap(FIX_PUD); /* Move to swapper page table */ - csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE); + csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode); local_flush_tlb_all(); pt_ops_set_late(); diff --git a/arch/riscv/mm/kasan_init.c b/arch/riscv/mm/kasan_init.c index 1434a0225140..993f50571a3b 100644 --- a/arch/riscv/mm/kasan_init.c +++ b/arch/riscv/mm/kasan_init.c @@ -11,7 +11,29 @@ #include #include +/* + * Kasan shadow region must lie at a fixed address across sv39, sv48 and sv57 + * which is right before the kernel. + * + * For sv39, the region is aligned on PGDIR_SIZE so we only need to populate + * the page global directory with kasan_early_shadow_pmd. + * + * For sv48 and sv57, the region is not aligned on PGDIR_SIZE so the mapping + * must be divided as follows: + * - the first PGD entry, although incomplete, is populated with + * kasan_early_shadow_pud/p4d + * - the PGD entries in the middle are populated with kasan_early_shadow_pud/p4d + * - the last PGD entry is shared with the kernel mapping so populated at the + * lower levels pud/p4d + * + * In addition, when shallow populating a kasan region (for example vmalloc), + * this region may also not be aligned on PGDIR size, so we must go down to the + * pud level too. + */ + extern pgd_t early_pg_dir[PTRS_PER_PGD]; +extern struct pt_alloc_ops _pt_ops __initdata; +#define pt_ops _pt_ops static void __init kasan_populate_pte(pmd_t *pmd, unsigned long vaddr, unsigned long end) { @@ -35,15 +57,19 @@ static void __init kasan_populate_pte(pmd_t *pmd, unsigned long vaddr, unsigned set_pmd(pmd, pfn_pmd(PFN_DOWN(__pa(base_pte)), PAGE_TABLE)); } -static void __init kasan_populate_pmd(pgd_t *pgd, unsigned long vaddr, unsigned long end) +static void __init kasan_populate_pmd(pud_t *pud, unsigned long vaddr, unsigned long end) { phys_addr_t phys_addr; pmd_t *pmdp, *base_pmd; unsigned long next; - base_pmd = (pmd_t *)pgd_page_vaddr(*pgd); - if (base_pmd == lm_alias(kasan_early_shadow_pmd)) + if (pud_none(*pud)) { base_pmd = memblock_alloc(PTRS_PER_PMD * sizeof(pmd_t), PAGE_SIZE); + } else { + base_pmd = (pmd_t *)pud_pgtable(*pud); + if (base_pmd == lm_alias(kasan_early_shadow_pmd)) + base_pmd = memblock_alloc(PTRS_PER_PMD * sizeof(pmd_t), PAGE_SIZE); + } pmdp = base_pmd + pmd_index(vaddr); @@ -67,9 +93,72 @@ static void __init kasan_populate_pmd(pgd_t *pgd, unsigned long vaddr, unsigned * it entirely, memblock could allocate a page at a physical address * where KASAN is not populated yet and then we'd get a page fault. */ - set_pgd(pgd, pfn_pgd(PFN_DOWN(__pa(base_pmd)), PAGE_TABLE)); + set_pud(pud, pfn_pud(PFN_DOWN(__pa(base_pmd)), PAGE_TABLE)); +} + +static void __init kasan_populate_pud(pgd_t *pgd, + unsigned long vaddr, unsigned long end, + bool early) +{ + phys_addr_t phys_addr; + pud_t *pudp, *base_pud; + unsigned long next; + + if (early) { + /* + * We can't use pgd_page_vaddr here as it would return a linear + * mapping address but it is not mapped yet, but when populating + * early_pg_dir, we need the physical address and when populating + * swapper_pg_dir, we need the kernel virtual address so use + * pt_ops facility. + */ + base_pud = pt_ops.get_pud_virt(pfn_to_phys(_pgd_pfn(*pgd))); + } else { + base_pud = (pud_t *)pgd_page_vaddr(*pgd); + if (base_pud == lm_alias(kasan_early_shadow_pud)) + base_pud = memblock_alloc(PTRS_PER_PUD * sizeof(pud_t), PAGE_SIZE); + } + + pudp = base_pud + pud_index(vaddr); + + do { + next = pud_addr_end(vaddr, end); + + if (pud_none(*pudp) && IS_ALIGNED(vaddr, PUD_SIZE) && (next - vaddr) >= PUD_SIZE) { + if (early) { + phys_addr = __pa(((uintptr_t)kasan_early_shadow_pmd)); + set_pud(pudp, pfn_pud(PFN_DOWN(phys_addr), PAGE_TABLE)); + continue; + } else { + phys_addr = memblock_phys_alloc(PUD_SIZE, PUD_SIZE); + if (phys_addr) { + set_pud(pudp, pfn_pud(PFN_DOWN(phys_addr), PAGE_KERNEL)); + continue; + } + } + } + + kasan_populate_pmd(pudp, vaddr, next); + } while (pudp++, vaddr = next, vaddr != end); + + /* + * Wait for the whole PGD to be populated before setting the PGD in + * the page table, otherwise, if we did set the PGD before populating + * it entirely, memblock could allocate a page at a physical address + * where KASAN is not populated yet and then we'd get a page fault. + */ + if (!early) + set_pgd(pgd, pfn_pgd(PFN_DOWN(__pa(base_pud)), PAGE_TABLE)); } +#define kasan_early_shadow_pgd_next (pgtable_l4_enabled ? \ + (uintptr_t)kasan_early_shadow_pud : \ + (uintptr_t)kasan_early_shadow_pmd) +#define kasan_populate_pgd_next(pgdp, vaddr, next, early) \ + (pgtable_l4_enabled ? \ + kasan_populate_pud(pgdp, vaddr, next, early) : \ + kasan_populate_pmd((pud_t *)pgdp, vaddr, next)) + static void __init kasan_populate_pgd(pgd_t *pgdp, unsigned long vaddr, unsigned long end, bool early) @@ -102,7 +191,7 @@ static void __init kasan_populate_pgd(pgd_t *pgdp, } } - kasan_populate_pmd(pgdp, vaddr, next); + kasan_populate_pgd_next(pgdp, vaddr, next, early); } while (pgdp++, vaddr = next, vaddr != end); } @@ -157,18 +246,54 @@ static void __init kasan_populate(void *start, void *end) memset(start, KASAN_SHADOW_INIT, end - start); } +static void __init kasan_shallow_populate_pud(pgd_t *pgdp, + unsigned long vaddr, unsigned long end, + bool kasan_populate) +{ + unsigned long next; + pud_t *pudp, *base_pud; + pmd_t *base_pmd; + bool is_kasan_pmd; + + base_pud = (pud_t *)pgd_page_vaddr(*pgdp); + pudp = base_pud + pud_index(vaddr); + + if (kasan_populate) + memcpy(base_pud, (void *)kasan_early_shadow_pgd_next, + sizeof(pud_t) * PTRS_PER_PUD); + + do { + next = pud_addr_end(vaddr, end); + is_kasan_pmd = (pud_pgtable(*pudp) == lm_alias(kasan_early_shadow_pmd)); + + if (is_kasan_pmd) { + base_pmd = memblock_alloc(PAGE_SIZE, PAGE_SIZE); + set_pud(pudp, pfn_pud(PFN_DOWN(__pa(base_pmd)), PAGE_TABLE)); + } + } while (pudp++, vaddr = next, vaddr != end); +} + static void __init kasan_shallow_populate_pgd(unsigned long vaddr, unsigned long end) { unsigned long next; void *p; pgd_t *pgd_k = pgd_offset_k(vaddr); + bool is_kasan_pgd_next; do { next = pgd_addr_end(vaddr, end); - if (pgd_page_vaddr(*pgd_k) == (unsigned long)lm_alias(kasan_early_shadow_pmd)) { + is_kasan_pgd_next = (pgd_page_vaddr(*pgd_k) == + (unsigned long)lm_alias(kasan_early_shadow_pgd_next)); + + if (is_kasan_pgd_next) { p = memblock_alloc(PAGE_SIZE, PAGE_SIZE); set_pgd(pgd_k, pfn_pgd(PFN_DOWN(__pa(p)), PAGE_TABLE)); } + + if (IS_ALIGNED(vaddr, PGDIR_SIZE) && (next - vaddr) >= PGDIR_SIZE) + continue; + + kasan_shallow_populate_pud(pgd_k, vaddr, next, is_kasan_pgd_next); } while (pgd_k++, vaddr = next, vaddr != end); } diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c index 26e69788f27a..b3db5d91ed38 100644 --- a/drivers/firmware/efi/libstub/efi-stub.c +++ b/drivers/firmware/efi/libstub/efi-stub.c @@ -40,6 +40,8 @@ #ifdef CONFIG_ARM64 # define EFI_RT_VIRTUAL_LIMIT DEFAULT_MAP_WINDOW_64 +#elif defined(CONFIG_RISCV) +# define EFI_RT_VIRTUAL_LIMIT TASK_SIZE_MIN #else # define EFI_RT_VIRTUAL_LIMIT TASK_SIZE #endif -- cgit v1.2.3 From c774de22c430733487f70d755067d9ea55dbe6de Mon Sep 17 00:00:00 2001 From: Alexandre Ghiti Date: Mon, 6 Dec 2021 11:46:53 +0100 Subject: riscv: Explicit comment about user virtual address space size Define precisely the size of the user accessible virtual space size for sv32/39/48 mmu types and explain why the whole virtual address space is split into 2 equal chunks between kernel and user space. Signed-off-by: Alexandre Ghiti Reviewed-by: Anup Patel Reviewed-by: Palmer Dabbelt Signed-off-by: Palmer Dabbelt --- arch/riscv/include/asm/pgtable.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'arch/riscv/include/asm') diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index 2ab6650d3926..d0a96b507561 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -685,6 +685,15 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma, /* * Task size is 0x4000000000 for RV64 or 0x9fc00000 for RV32. * Note that PGDIR_SIZE must evenly divide TASK_SIZE. + * Task size is: + * - 0x9fc00000 (~2.5GB) for RV32. + * - 0x4000000000 ( 256GB) for RV64 using SV39 mmu + * - 0x800000000000 ( 128TB) for RV64 using SV48 mmu + * + * Note that PGDIR_SIZE must evenly divide TASK_SIZE since "RISC-V + * Instruction Set Manual Volume II: Privileged Architecture" states that + * "load and store effective addresses, which are 64bits, must have bits + * 63–48 all equal to bit 47, or else a page-fault exception will occur." */ #ifdef CONFIG_64BIT #define TASK_SIZE (PGDIR_SIZE * PTRS_PER_PGD / 2) -- cgit v1.2.3