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

Catalin Marinas catalin.marinas at arm.com
Thu Jan 24 06:39:35 EST 2013


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



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