On Tue, Jan 5, 2021 at 1:33 AM Alexandre Ghiti <alex@xxxxxxxx> wrote: > > 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 <alex@xxxxxxxx> > --- > arch/riscv/Kconfig | 10 ---------- > arch/riscv/include/asm/pgtable.h | 11 +++++++++-- > arch/riscv/include/asm/sparsemem.h | 6 +++++- > 3 files changed, 14 insertions(+), 13 deletions(-) > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index 44377fd7860e..2979a44103be 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -122,16 +122,6 @@ config ZONE_DMA32 > bool > default y if 64BIT > > -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_2GB > diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h > index 102b728ca146..c7973bfd65bc 100644 > --- a/arch/riscv/include/asm/pgtable.h > +++ b/arch/riscv/include/asm/pgtable.h > @@ -43,8 +43,14 @@ > * 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) > @@ -83,6 +89,7 @@ > #endif /* CONFIG_64BIT */ > > #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 */ > @@ -453,7 +460,7 @@ static inline int ptep_clear_flush_young(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 */ > > -- > 2.20.1 > Looks good to me. Reviewed-by: Anup Patel <anup@xxxxxxxxxxxxxx> Regards, Anup
