Le 01/12/2021 à 15:41, Nicholas Piggin a écrit :
> To avoid any functional changes to radix paths when building with hash
> MMU support disabled (and CONFIG_PPC_MM_SLICES=n), always define the
> arch get_unmapped_area calls on 64s platforms.
>
> Signed-off-by: Nicholas Piggin <npig...@gmail.com>
> ---
> arch/powerpc/include/asm/book3s/64/hash.h | 4 ---
> arch/powerpc/include/asm/book3s/64/mmu.h | 6 ++++
> arch/powerpc/mm/hugetlbpage.c | 16 ++++++---
> arch/powerpc/mm/mmap.c | 40 +++++++++++++++++++----
> arch/powerpc/mm/slice.c | 20 ------------
> 5 files changed, 51 insertions(+), 35 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/book3s/64/hash.h
> b/arch/powerpc/include/asm/book3s/64/hash.h
> index 674fe0e890dc..a7a0572f3846 100644
> --- a/arch/powerpc/include/asm/book3s/64/hash.h
> +++ b/arch/powerpc/include/asm/book3s/64/hash.h
> @@ -99,10 +99,6 @@
> * Defines the address of the vmemap area, in its own region on
> * hash table CPUs.
> */
> -#ifdef CONFIG_PPC_MM_SLICES
> -#define HAVE_ARCH_UNMAPPED_AREA
> -#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
> -#endif /* CONFIG_PPC_MM_SLICES */
>
> /* PTEIDX nibble */
> #define _PTEIDX_SECONDARY 0x8
> diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h
> b/arch/powerpc/include/asm/book3s/64/mmu.h
> index c02f42d1031e..015d7d972d16 100644
> --- a/arch/powerpc/include/asm/book3s/64/mmu.h
> +++ b/arch/powerpc/include/asm/book3s/64/mmu.h
> @@ -4,6 +4,12 @@
>
> #include <asm/page.h>
>
> +#ifdef CONFIG_HUGETLB_PAGE
> +#define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
> +#endif
> +#define HAVE_ARCH_UNMAPPED_AREA
> +#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
> +
> #ifndef __ASSEMBLY__
> /*
> * Page size definition
> diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
> index 82d8b368ca6d..ddead41e2194 100644
> --- a/arch/powerpc/mm/hugetlbpage.c
> +++ b/arch/powerpc/mm/hugetlbpage.c
> @@ -542,20 +542,26 @@ struct page *follow_huge_pd(struct vm_area_struct *vma,
> return page;
> }
>
> -#ifdef CONFIG_PPC_MM_SLICES
> +#ifdef HAVE_ARCH_HUGETLB_UNMAPPED_AREA
> +static inline int file_to_psize(struct file *file)
> +{
> + struct hstate *hstate = hstate_file(file);
> + return shift_to_mmu_psize(huge_page_shift(hstate));
> +}
> +
> unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long
> addr,
> unsigned long len, unsigned long pgoff,
> unsigned long flags)
> {
> - struct hstate *hstate = hstate_file(file);
> - int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
> -
> #ifdef CONFIG_PPC_RADIX_MMU
> if (radix_enabled())
> return radix__hugetlb_get_unmapped_area(file, addr, len,
> pgoff, flags);
> #endif
> - return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1);
> +#ifdef CONFIG_PPC_MM_SLICES
> + return slice_get_unmapped_area(addr, len, flags, file_to_psize(file),
> 1);
> +#endif
> + BUG();
We shouldn't had new instances of BUG().
BUILD_BUG() should do the trick here.
> }
> #endif
>
> diff --git a/arch/powerpc/mm/mmap.c b/arch/powerpc/mm/mmap.c
> index ae683fdc716c..c475cf810aa8 100644
> --- a/arch/powerpc/mm/mmap.c
> +++ b/arch/powerpc/mm/mmap.c
> @@ -80,6 +80,7 @@ static inline unsigned long mmap_base(unsigned long rnd,
> return PAGE_ALIGN(DEFAULT_MAP_WINDOW - gap - rnd);
> }
>
> +#ifdef HAVE_ARCH_UNMAPPED_AREA
> #ifdef CONFIG_PPC_RADIX_MMU
> /*
> * Same function as generic code used only for radix, because we don't need
> to overload
> @@ -181,11 +182,42 @@ radix__arch_get_unmapped_area_topdown(struct file *filp,
> */
> return radix__arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
> }
> +#endif
> +
> +unsigned long arch_get_unmapped_area(struct file *filp,
> + unsigned long addr,
> + unsigned long len,
> + unsigned long pgoff,
> + unsigned long flags)
> +{
> +#ifdef CONFIG_PPC_MM_SLICES
> + return slice_get_unmapped_area(addr, len, flags,
> +
> mm_ctx_user_psize(¤t->mm->context), 0);
> +#else
> + BUG();
Same.
And the #else isn't needed
> +#endif
> +}
> +
> +unsigned long arch_get_unmapped_area_topdown(struct file *filp,
> + const unsigned long addr0,
> + const unsigned long len,
> + const unsigned long pgoff,
> + const unsigned long flags)
> +{
> +#ifdef CONFIG_PPC_MM_SLICES
> + return slice_get_unmapped_area(addr0, len, flags,
> +
> mm_ctx_user_psize(¤t->mm->context), 1);
> +#else
> + BUG();
Same
And the #else isn't needed
> +#endif
> +}
> +#endif /* HAVE_ARCH_UNMAPPED_AREA */
>
> static void radix__arch_pick_mmap_layout(struct mm_struct *mm,
> unsigned long random_factor,
> struct rlimit *rlim_stack)
> {
> +#ifdef CONFIG_PPC_RADIX_MMU
> if (mmap_is_legacy(rlim_stack)) {
> mm->mmap_base = TASK_UNMAPPED_BASE;
> mm->get_unmapped_area = radix__arch_get_unmapped_area;
> @@ -193,13 +225,9 @@ static void radix__arch_pick_mmap_layout(struct
> mm_struct *mm,
> mm->mmap_base = mmap_base(random_factor, rlim_stack);
> mm->get_unmapped_area = radix__arch_get_unmapped_area_topdown;
> }
> -}
> -#else
> -/* dummy */
> -extern void radix__arch_pick_mmap_layout(struct mm_struct *mm,
> - unsigned long random_factor,
> - struct rlimit *rlim_stack);
> #endif
> +}
> +
> /*
> * This function, called very early during the creation of a new
> * process VM image, sets up which VM layout function to use:
> diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
> index 82b45b1cb973..f42711f865f3 100644
> --- a/arch/powerpc/mm/slice.c
> +++ b/arch/powerpc/mm/slice.c
> @@ -639,26 +639,6 @@ unsigned long slice_get_unmapped_area(unsigned long
> addr, unsigned long len,
> }
> EXPORT_SYMBOL_GPL(slice_get_unmapped_area);
>
> -unsigned long arch_get_unmapped_area(struct file *filp,
> - unsigned long addr,
> - unsigned long len,
> - unsigned long pgoff,
> - unsigned long flags)
> -{
> - return slice_get_unmapped_area(addr, len, flags,
> -
> mm_ctx_user_psize(¤t->mm->context), 0);
> -}
> -
> -unsigned long arch_get_unmapped_area_topdown(struct file *filp,
> - const unsigned long addr0,
> - const unsigned long len,
> - const unsigned long pgoff,
> - const unsigned long flags)
> -{
> - return slice_get_unmapped_area(addr0, len, flags,
> -
> mm_ctx_user_psize(¤t->mm->context), 1);
> -}
> -
> unsigned int notrace get_slice_psize(struct mm_struct *mm, unsigned long
> addr)
> {
> unsigned char *psizes;
>
