linux-kernel - Re: [PATCH 05/16] huge tmpfs: move shmem_huge

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAHbLzkqN0L9S3shxU-2PJBeqbKwt4knFN2_Nh-tAcfq=QfLJDw@mail.gmail.com>
Date:   Fri, 30 Jul 2021 14:57:03 -0700
From:   Yang Shi <shy828301@...il.com>
To:     Hugh Dickins <hughd@...gle.com>
Cc:     Andrew Morton <akpm@...ux-foundation.org>,
        Shakeel Butt <shakeelb@...gle.com>,
        "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
        Miaohe Lin <linmiaohe@...wei.com>,
        Mike Kravetz <mike.kravetz@...cle.com>,
        Michal Hocko <mhocko@...e.com>,
        Rik van Riel <riel@...riel.com>,
        Christoph Hellwig <hch@...radead.org>,
        Matthew Wilcox <willy@...radead.org>,
        "Eric W. Biederman" <ebiederm@...ssion.com>,
        Alexey Gladkov <legion@...nel.org>,
        Chris Wilson <chris@...is-wilson.co.uk>,
        Matthew Auld <matthew.auld@...el.com>,
        Linux FS-devel Mailing List <linux-fsdevel@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        linux-api@...r.kernel.org, Linux MM <linux-mm@...ck.org>
Subject: Re: [PATCH 05/16] huge tmpfs: move shmem_huge_enabled() upwards

On Fri, Jul 30, 2021 at 12:39 AM Hugh Dickins <hughd@...gle.com> wrote:
>
> shmem_huge_enabled() is about to be enhanced into shmem_is_huge(),
> so that it can be used more widely throughout: before making functional
> changes, shift it to its final position (to avoid forward declaration).
>
> Signed-off-by: Hugh Dickins <hughd@...gle.com>

Reviewed-by: Yang Shi <shy828301@...il.com>

> ---
>  mm/shmem.c | 72 ++++++++++++++++++++++++++----------------------------
>  1 file changed, 35 insertions(+), 37 deletions(-)
>
> diff --git a/mm/shmem.c b/mm/shmem.c
> index c6fa6f4f2db8..740d48ef1eb5 100644
> --- a/mm/shmem.c
> +++ b/mm/shmem.c
> @@ -476,6 +476,41 @@ static bool shmem_confirm_swap(struct address_space *mapping,
>
>  static int shmem_huge __read_mostly;
>
> +bool shmem_huge_enabled(struct vm_area_struct *vma)
> +{
> +       struct inode *inode = file_inode(vma->vm_file);
> +       struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
> +       loff_t i_size;
> +       pgoff_t off;
> +
> +       if ((vma->vm_flags & VM_NOHUGEPAGE) ||
> +           test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
> +               return false;
> +       if (shmem_huge == SHMEM_HUGE_FORCE)
> +               return true;
> +       if (shmem_huge == SHMEM_HUGE_DENY)
> +               return false;
> +       switch (sbinfo->huge) {
> +       case SHMEM_HUGE_NEVER:
> +               return false;
> +       case SHMEM_HUGE_ALWAYS:
> +               return true;
> +       case SHMEM_HUGE_WITHIN_SIZE:
> +               off = round_up(vma->vm_pgoff, HPAGE_PMD_NR);
> +               i_size = round_up(i_size_read(inode), PAGE_SIZE);
> +               if (i_size >= HPAGE_PMD_SIZE &&
> +                               i_size >> PAGE_SHIFT >= off)
> +                       return true;
> +               fallthrough;
> +       case SHMEM_HUGE_ADVISE:
> +               /* TODO: implement fadvise() hints */
> +               return (vma->vm_flags & VM_HUGEPAGE);
> +       default:
> +               VM_BUG_ON(1);
> +               return false;
> +       }
> +}
> +
>  #if defined(CONFIG_SYSFS)
>  static int shmem_parse_huge(const char *str)
>  {
> @@ -3995,43 +4030,6 @@ struct kobj_attribute shmem_enabled_attr =
>         __ATTR(shmem_enabled, 0644, shmem_enabled_show, shmem_enabled_store);
>  #endif /* CONFIG_TRANSPARENT_HUGEPAGE && CONFIG_SYSFS */
>
> -#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> -bool shmem_huge_enabled(struct vm_area_struct *vma)
> -{
> -       struct inode *inode = file_inode(vma->vm_file);
> -       struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
> -       loff_t i_size;
> -       pgoff_t off;
> -
> -       if ((vma->vm_flags & VM_NOHUGEPAGE) ||
> -           test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
> -               return false;
> -       if (shmem_huge == SHMEM_HUGE_FORCE)
> -               return true;
> -       if (shmem_huge == SHMEM_HUGE_DENY)
> -               return false;
> -       switch (sbinfo->huge) {
> -               case SHMEM_HUGE_NEVER:
> -                       return false;
> -               case SHMEM_HUGE_ALWAYS:
> -                       return true;
> -               case SHMEM_HUGE_WITHIN_SIZE:
> -                       off = round_up(vma->vm_pgoff, HPAGE_PMD_NR);
> -                       i_size = round_up(i_size_read(inode), PAGE_SIZE);
> -                       if (i_size >= HPAGE_PMD_SIZE &&
> -                                       i_size >> PAGE_SHIFT >= off)
> -                               return true;
> -                       fallthrough;
> -               case SHMEM_HUGE_ADVISE:
> -                       /* TODO: implement fadvise() hints */
> -                       return (vma->vm_flags & VM_HUGEPAGE);
> -               default:
> -                       VM_BUG_ON(1);
> -                       return false;
> -       }
> -}
> -#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
> -
>  #else /* !CONFIG_SHMEM */
>
>  /*
> --
> 2.26.2
>