[PATCH v3 02/13] arm64/mm: add create_pgd_mapping() to create private page tables
Will Deacon
will.deacon at arm.com
Tue Nov 25 06:32:47 PST 2014
On Tue, Nov 18, 2014 at 12:57:01PM +0000, Ard Biesheuvel wrote:
> For UEFI, we need to install the memory mappings used for Runtime Services
> in a dedicated set of page tables. Add create_pgd_mapping(), which allows
> us to allocate and install those page table entries early.
>
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel at linaro.org>
> ---
> arch/arm64/include/asm/mmu.h | 3 +++
> arch/arm64/include/asm/pgtable.h | 5 +++++
> arch/arm64/mm/mmu.c | 43 ++++++++++++++++++++--------------------
> 3 files changed, 30 insertions(+), 21 deletions(-)
Looks fairly mechanical to me:
Reviewed-by: Will Deacon <will.deacon at arm.com>
Will
> diff --git a/arch/arm64/include/asm/mmu.h b/arch/arm64/include/asm/mmu.h
> index c2f006c48bdb..5fd40c43be80 100644
> --- a/arch/arm64/include/asm/mmu.h
> +++ b/arch/arm64/include/asm/mmu.h
> @@ -33,5 +33,8 @@ extern void __iomem *early_io_map(phys_addr_t phys, unsigned long virt);
> extern void init_mem_pgprot(void);
> /* create an identity mapping for memory (or io if map_io is true) */
> extern void create_id_mapping(phys_addr_t addr, phys_addr_t size, int map_io);
> +extern void create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys,
> + unsigned long virt, phys_addr_t size,
> + pgprot_t prot);
>
> #endif
> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
> index 41a43bf26492..1abe4d08725b 100644
> --- a/arch/arm64/include/asm/pgtable.h
> +++ b/arch/arm64/include/asm/pgtable.h
> @@ -264,6 +264,11 @@ static inline pmd_t pte_pmd(pte_t pte)
> return __pmd(pte_val(pte));
> }
>
> +static inline pgprot_t mk_sect_prot(pgprot_t prot)
> +{
> + return __pgprot(pgprot_val(prot) & ~PTE_TABLE_BIT);
> +}
> +
> /*
> * THP definitions.
> */
> diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
> index 83e6713143a3..4d583aa9ff4e 100644
> --- a/arch/arm64/mm/mmu.c
> +++ b/arch/arm64/mm/mmu.c
> @@ -157,20 +157,10 @@ static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
>
> static void __init alloc_init_pmd(struct mm_struct *mm, pud_t *pud,
> unsigned long addr, unsigned long end,
> - phys_addr_t phys, int map_io)
> + phys_addr_t phys, pgprot_t prot)
> {
> pmd_t *pmd;
> unsigned long next;
> - pmdval_t prot_sect;
> - pgprot_t prot_pte;
> -
> - if (map_io) {
> - prot_sect = PROT_SECT_DEVICE_nGnRE;
> - prot_pte = __pgprot(PROT_DEVICE_nGnRE);
> - } else {
> - prot_sect = PROT_SECT_NORMAL_EXEC;
> - prot_pte = PAGE_KERNEL_EXEC;
> - }
>
> /*
> * Check for initial section mappings in the pgd/pud and remove them.
> @@ -186,7 +176,8 @@ static void __init alloc_init_pmd(struct mm_struct *mm, pud_t *pud,
> /* try section mapping first */
> if (((addr | next | phys) & ~SECTION_MASK) == 0) {
> pmd_t old_pmd =*pmd;
> - set_pmd(pmd, __pmd(phys | prot_sect));
> + set_pmd(pmd, __pmd(phys |
> + pgprot_val(mk_sect_prot(prot))));
> /*
> * Check for previous table entries created during
> * boot (__create_page_tables) and flush them.
> @@ -195,7 +186,7 @@ static void __init alloc_init_pmd(struct mm_struct *mm, pud_t *pud,
> flush_tlb_all();
> } else {
> alloc_init_pte(pmd, addr, next, __phys_to_pfn(phys),
> - prot_pte);
> + prot);
> }
> phys += next - addr;
> } while (pmd++, addr = next, addr != end);
> @@ -203,7 +194,7 @@ static void __init alloc_init_pmd(struct mm_struct *mm, pud_t *pud,
>
> static void __init alloc_init_pud(struct mm_struct *mm, pgd_t *pgd,
> unsigned long addr, unsigned long end,
> - unsigned long phys, int map_io)
> + unsigned long phys, pgprot_t prot)
> {
> pud_t *pud;
> unsigned long next;
> @@ -221,10 +212,11 @@ static void __init alloc_init_pud(struct mm_struct *mm, pgd_t *pgd,
> /*
> * For 4K granule only, attempt to put down a 1GB block
> */
> - if (!map_io && (PAGE_SHIFT == 12) &&
> + if ((PAGE_SHIFT == 12) &&
> ((addr | next | phys) & ~PUD_MASK) == 0) {
> pud_t old_pud = *pud;
> - set_pud(pud, __pud(phys | PROT_SECT_NORMAL_EXEC));
> + set_pud(pud, __pud(phys |
> + pgprot_val(mk_sect_prot(prot))));
>
> /*
> * If we have an old value for a pud, it will
> @@ -239,7 +231,7 @@ static void __init alloc_init_pud(struct mm_struct *mm, pgd_t *pgd,
> flush_tlb_all();
> }
> } else {
> - alloc_init_pmd(mm, pud, addr, next, phys, map_io);
> + alloc_init_pmd(mm, pud, addr, next, phys, prot);
> }
> phys += next - addr;
> } while (pud++, addr = next, addr != end);
> @@ -251,7 +243,7 @@ static void __init alloc_init_pud(struct mm_struct *mm, pgd_t *pgd,
> */
> static void __init __create_mapping(struct mm_struct *mm, pgd_t *pgd,
> phys_addr_t phys, unsigned long virt,
> - phys_addr_t size, int map_io)
> + phys_addr_t size, pgprot_t prot)
> {
> unsigned long addr, length, end, next;
>
> @@ -261,7 +253,7 @@ static void __init __create_mapping(struct mm_struct *mm, pgd_t *pgd,
> end = addr + length;
> do {
> next = pgd_addr_end(addr, end);
> - alloc_init_pud(mm, pgd, addr, next, phys, map_io);
> + alloc_init_pud(mm, pgd, addr, next, phys, prot);
> phys += next - addr;
> } while (pgd++, addr = next, addr != end);
> }
> @@ -275,7 +267,7 @@ static void __init create_mapping(phys_addr_t phys, unsigned long virt,
> return;
> }
> __create_mapping(&init_mm, pgd_offset_k(virt & PAGE_MASK), phys, virt,
> - size, 0);
> + size, PAGE_KERNEL_EXEC);
> }
>
> void __init create_id_mapping(phys_addr_t addr, phys_addr_t size, int map_io)
> @@ -285,7 +277,16 @@ void __init create_id_mapping(phys_addr_t addr, phys_addr_t size, int map_io)
> return;
> }
> __create_mapping(&init_mm, &idmap_pg_dir[pgd_index(addr)],
> - addr, addr, size, map_io);
> + addr, addr, size,
> + map_io ? __pgprot(PROT_DEVICE_nGnRE)
> + : PAGE_KERNEL_EXEC);
> +}
> +
> +void __init create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys,
> + unsigned long virt, phys_addr_t size,
> + pgprot_t prot)
> +{
> + __create_mapping(mm, pgd_offset(mm, virt), phys, virt, size, prot);
> }
>
> static void __init map_mem(void)
> --
> 1.8.3.2
>
>
More information about the linux-arm-kernel
mailing list