Re: [PATCH v6 01/15] ARM: Add page table and page defines needed by KVM

Catalin Marinas
2013-01-24T11:41:12Z

Hi Christoffer,

On Wed, Jan 16, 2013 at 05:57:26PM +0000, Christoffer Dall wrote:
> diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
> index a3f3792..6ef8afd 100644
> --- a/arch/arm/include/asm/pgtable-3level.h
> +++ b/arch/arm/include/asm/pgtable-3level.h
> @@ -104,11 +104,29 @@
> */
> #define L_PGD_SWAPPER (_AT(pgdval_t, 1) << 55) /* swapper_pg_dir entry */
>
> +/*
> + * 2nd stage PTE definitions for LPAE.
> + */
> +#define L_PTE_S2_MT_UNCACHED (_AT(pteval_t, 0x5) << 2) /* MemAttr[3:0] */
> +#define L_PTE_S2_MT_WRITETHROUGH (_AT(pteval_t, 0xa) << 2) /* MemAttr[3:0] */
> +#define L_PTE_S2_MT_WRITEBACK (_AT(pteval_t, 0xf) << 2) /* MemAttr[3:0] */
> +#define L_PTE_S2_RDONLY (_AT(pteval_t, 1) << 6) /* HAP[1] */
> +#define L_PTE_S2_RDWR (_AT(pteval_t, 2) << 6) /* HAP[2:1] */

Why is this called L_PTE_S2_RDWR? The ARM ARM shows HAP[2:1] as 0b11 for
read/write and 0b10 for WRONLY.

> --- a/arch/arm/include/asm/pgtable.h
> +++ b/arch/arm/include/asm/pgtable.h
> @@ -70,6 +70,9 @@ extern void __pgd_error(const char *file, int line, pgd_t);
>
> extern pgprot_t pgprot_user;
> extern pgprot_t pgprot_kernel;
> +extern pgprot_t pgprot_hyp_device;
> +extern pgprot_t pgprot_s2;
> +extern pgprot_t pgprot_s2_device;
>
> #define _MOD_PROT(p, b) __pgprot(pgprot_val(p) | (b))
>
> @@ -82,6 +85,10 @@ extern pgprot_t pgprot_kernel;
> #define PAGE_READONLY_EXEC _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
> #define PAGE_KERNEL _MOD_PROT(pgprot_kernel, L_PTE_XN)
> #define PAGE_KERNEL_EXEC pgprot_kernel
> +#define PAGE_HYP _MOD_PROT(pgprot_kernel, L_PTE_HYP)
> +#define PAGE_HYP_DEVICE _MOD_PROT(pgprot_hyp_device, L_PTE_HYP)
> +#define PAGE_S2 _MOD_PROT(pgprot_s2, L_PTE_S2_RDONLY)
> +#define PAGE_S2_DEVICE _MOD_PROT(pgprot_s2_device, L_PTE_USER | L_PTE_S2_RDONLY)

Are these S2 read-only by default?

--
Catalin