Re: [PATCH] riscv: using page table index in setup_vm()

[Mike Rapoport <rppt@linux.ibm.com>]

On Mon, May 20, 2019 at 05:48:24PM +0900, JaeJoon Jung wrote:
> From: JaeJoon Jung <rgbi3307@gmail.com>
> 
> The page table index macro are defined already in pgtable.h as below:
> ///arch/riscv/include/asm/pgtable.h
> #define pgd_index(addr)     (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
> #define pte_index(addr)     (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
> ///arch/riscv/include/asm/pgtable-64.h
> #define pmd_index(addr)     (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
> 
> But, In the arch/riscv/mm/init.c,
> I found that it does not use above macro in setup_vm().
> I wat to use this macro in setup_vm() as below:

I'd suggest the following changelog:
-----------------------------------------
riscv: setup_vm: use p?d_index() instead of its open coded implementation

The page table indexing macros are defined in include/asm/pgtable.h, but
setup_vm() uses an open coded implementation.

Replace it with the appropriate macros.
-----------------------------------------


> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
> Cc: Anup Patel <anup.patel@wdc.com>
> Cc: linux-riscv@lists.infradead.org
 
Otherwise

Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
 
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index bc7b77e34d09..785954b776ac 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> 
>  asmlinkage void __init setup_vm(void)
>  {
>         extern char _start;
> @@ -223,13 +190,13 @@ asmlinkage void __init setup_vm(void)
>         BUG_ON((pa % (PAGE_SIZE * PTRS_PER_PTE)) != 0);
> 
>  #ifndef __PAGETABLE_PMD_FOLDED
> -       trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
> +       trampoline_pg_dir[pgd_index(PAGE_OFFSET)] =
>                 pfn_pgd(PFN_DOWN((uintptr_t)trampoline_pmd),
>                         __pgprot(_PAGE_TABLE));
>         trampoline_pmd[0] = pfn_pmd(PFN_DOWN(pa), prot);
> 
>         for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
> -               size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
> +               size_t o = pgd_index(PAGE_OFFSET) + i;
> 
>                 swapper_pg_dir[o] =
>                         pfn_pgd(PFN_DOWN((uintptr_t)swapper_pmd) + i,
> @@ -238,24 +205,23 @@ asmlinkage void __init setup_vm(void)
>         for (i = 0; i < ARRAY_SIZE(swapper_pmd); i++)
>                 swapper_pmd[i] = pfn_pmd(PFN_DOWN(pa + i * PMD_SIZE), prot);
> 
> -       swapper_pg_dir[(FIXADDR_START >> PGDIR_SHIFT) % PTRS_PER_PGD] =
> +       swapper_pg_dir[pgd_index(FIXADDR_START)] =
>                 pfn_pgd(PFN_DOWN((uintptr_t)fixmap_pmd),
>                                 __pgprot(_PAGE_TABLE));
> -       fixmap_pmd[(FIXADDR_START >> PMD_SHIFT) % PTRS_PER_PMD] =
> +       fixmap_pmd[pmd_index(FIXADDR_START)] =
>                 pfn_pmd(PFN_DOWN((uintptr_t)fixmap_pte),
>                                 __pgprot(_PAGE_TABLE));
>  #else
> -       trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
> +       trampoline_pg_dir[pgd_index(PAGE_OFFSET)] =
>                 pfn_pgd(PFN_DOWN(pa), prot);
> 
>         for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
> -               size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
> +               size_t o = pgd_index(PAGE_OFFSET) + i;
> 
>                 swapper_pg_dir[o] =
>                         pfn_pgd(PFN_DOWN(pa + i * PGDIR_SIZE), prot);
>         }
> -
> -       swapper_pg_dir[(FIXADDR_START >> PGDIR_SHIFT) % PTRS_PER_PGD] =
> +       swapper_pg_dir[pgd_index(FIXADDR_START)] =
>                 pfn_pgd(PFN_DOWN((uintptr_t)fixmap_pte),
>                                 __pgprot(_PAGE_TABLE));
>  #endif
> 
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv
> 

-- 
Sincerely yours,
Mike.


_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv