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References: <20191024093716.49420-1-steven.price@arm.com> <20191024093716.49420-8-steven.price@arm.com>
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From:   Zong Li <zongbox@gmail.com>
Date:   Thu, 24 Oct 2019 21:09:03 +0800
Message-ID: <CA+ZOyajoTagPdMA=WaQVLZ+aPzKmdX=j+apRVUsvpbVF_HtnQw@mail.gmail.com>
Subject: Re: [PATCH v13 07/22] riscv: mm: Add p?d_leaf() definitions
To:     Steven Price <steven.price@arm.com>
Cc:     linux-mm@kvack.org, Mark Rutland <Mark.Rutland@arm.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>, linux-riscv@lists.infradead.org,
        Will Deacon <will@kernel.org>,
        "Liang, Kan" <kan.liang@linux.intel.com>,
        Alexandre Ghiti <alex@ghiti.fr>, x86@kernel.org,
        Ingo Molnar <mingo@redhat.com>,
        Palmer Dabbelt <palmer@sifive.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Arnd Bergmann <arnd@arndb.de>,
        =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= <jglisse@redhat.com>,
        Borislav Petkov <bp@alien8.de>,
        Andy Lutomirski <luto@kernel.org>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-arm-kernel@lists.infradead.org,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        James Morse <james.morse@arm.com>,
        Andrew Morton <akpm@linux-foundation.org>
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Steven Price <steven.price@arm.com> =E6=96=BC 2019=E5=B9=B410=E6=9C=8824=E6=
=97=A5 =E9=80=B1=E5=9B=9B =E4=B8=8B=E5=8D=885:40=E5=AF=AB=E9=81=93=EF=BC=9A
>
> walk_page_range() is going to be allowed to walk page tables other than
> those of user space. For this it needs to know when it has reached a
> 'leaf' entry in the page tables. This information is provided by the
> p?d_leaf() functions/macros.
>
> For riscv a page is a leaf page when it has a read, write or execute bit
> set on it.
>
> CC: Palmer Dabbelt <palmer@sifive.com>
> CC: Albert Ou <aou@eecs.berkeley.edu>
> CC: linux-riscv@lists.infradead.org
> Reviewed-by: Alexandre Ghiti <alex@ghiti.fr>
> Acked-by: Paul Walmsley <paul.walmsley@sifive.com> # for arch/riscv
> Signed-off-by: Steven Price <steven.price@arm.com>
> ---
>  arch/riscv/include/asm/pgtable-64.h | 7 +++++++
>  arch/riscv/include/asm/pgtable.h    | 7 +++++++
>  2 files changed, 14 insertions(+)
>
> diff --git a/arch/riscv/include/asm/pgtable-64.h b/arch/riscv/include/asm=
/pgtable-64.h
> index 74630989006d..4c4d2c65ba6c 100644
> --- a/arch/riscv/include/asm/pgtable-64.h
> +++ b/arch/riscv/include/asm/pgtable-64.h
> @@ -43,6 +43,13 @@ static inline int pud_bad(pud_t pud)
>         return !pud_present(pud);
>  }
>
> +#define pud_leaf       pud_leaf
> +static inline int pud_leaf(pud_t pud)
> +{
> +       return pud_present(pud) &&
> +              (pud_val(pud) & (_PAGE_READ | _PAGE_WRITE | _PAGE_EXEC));
> +}
> +
>  static inline void set_pud(pud_t *pudp, pud_t pud)
>  {
>         *pudp =3D pud;
> diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pg=
table.h
> index 7255f2d8395b..3aa972dda75a 100644
> --- a/arch/riscv/include/asm/pgtable.h
> +++ b/arch/riscv/include/asm/pgtable.h
> @@ -130,6 +130,13 @@ static inline int pmd_bad(pmd_t pmd)
>         return !pmd_present(pmd);
>  }
>
> +#define pmd_leaf       pmd_leaf
> +static inline int pmd_leaf(pmd_t pmd)
> +{
> +       return pmd_present(pmd) &&
> +              (pmd_val(pmd) & (_PAGE_READ | _PAGE_WRITE | _PAGE_EXEC));
> +}
> +
>  static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
>  {
>         *pmdp =3D pmd;
> --
> 2.20.1
>
>
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv

It's good to me.

Reviewed-by: Zong Li <zong.li@sifive.com>