[PATCH v2 01/10] riscv: Allow to dynamically define VA_BITS
From: Alexandre Ghiti <hidden>
Date: 2021-09-29 14:52:39
Also in:
linux-doc, linux-efi, linux-riscv, lkml
Subsystem:
risc-v architecture, the rest · Maintainers:
Paul Walmsley, Palmer Dabbelt, Albert Ou, Linus Torvalds
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 <redacted> --- arch/riscv/Kconfig | 10 ---------- arch/riscv/include/asm/pgtable.h | 10 ++++++++-- arch/riscv/include/asm/sparsemem.h | 6 +++++- 3 files changed, 13 insertions(+), 13 deletions(-)
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index c1abbc876e5b..ee61ecae3ae0 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig@@ -145,16 +145,6 @@ 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 && MAXPHYSMEM_1GB
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 39b550310ec6..e3e03226a50a 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h@@ -48,8 +48,14 @@ * 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)
@@ -651,7 +657,7 @@ 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 */
--
2.30.2