Hi Andrew,
> Daniel, have you had a chance to runtime test these various fiddles?
Yes, I've been testing with -fix and -fix-fix since they hit next. They
work fine for me on x86 and powerpc.
Regards,
Daniel
>
> From: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Subject: mm-add-apply_to_existing_pages-helper-fix
>
> reduce code duplication
>
> Cc: Daniel Axtens <dja@xxxxxxxxxx>
> Cc: Alexander Potapenko <glider@xxxxxxxxxx>
> Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
> Cc: Qian Cai <cai@xxxxxx>
> Cc: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> ---
>
> mm/memory.c | 43 +++++++++++++++++--------------------------
> 1 file changed, 17 insertions(+), 26 deletions(-)
>
> --- a/mm/memory.c~mm-add-apply_to_existing_pages-helper-fix
> +++ a/mm/memory.c
> @@ -2141,12 +2141,9 @@ static int apply_to_p4d_range(struct mm_
> return err;
> }
>
> -/*
> - * Scan a region of virtual memory, filling in page tables as necessary
> - * and calling a provided function on each leaf page table.
> - */
> -int apply_to_page_range(struct mm_struct *mm, unsigned long addr,
> - unsigned long size, pte_fn_t fn, void *data)
> +static int __apply_to_page_range(struct mm_struct *mm, unsigned long addr,
> + unsigned long size, pte_fn_t fn,
> + void *data, bool create)
> {
> pgd_t *pgd;
> unsigned long next;
> @@ -2159,13 +2156,25 @@ int apply_to_page_range(struct mm_struct
> pgd = pgd_offset(mm, addr);
> do {
> next = pgd_addr_end(addr, end);
> - err = apply_to_p4d_range(mm, pgd, addr, next, fn, data, true);
> + if (!create && pgd_none_or_clear_bad(pgd))
> + continue;
> + err = apply_to_p4d_range(mm, pgd, addr, next, fn, data, create);
> if (err)
> break;
> } while (pgd++, addr = next, addr != end);
>
> return err;
> }
> +
> +/*
> + * Scan a region of virtual memory, filling in page tables as necessary
> + * and calling a provided function on each leaf page table.
> + */
> +int apply_to_page_range(struct mm_struct *mm, unsigned long addr,
> + unsigned long size, pte_fn_t fn, void *data)
> +{
> + return __apply_to_page_range(mm, addr, size, fn, data, true);
> +}
> EXPORT_SYMBOL_GPL(apply_to_page_range);
>
> /*
> @@ -2178,25 +2187,7 @@ EXPORT_SYMBOL_GPL(apply_to_page_range);
> int apply_to_existing_pages(struct mm_struct *mm, unsigned long addr,
> unsigned long size, pte_fn_t fn, void *data)
> {
> - pgd_t *pgd;
> - unsigned long next;
> - unsigned long end = addr + size;
> - int err = 0;
> -
> - if (WARN_ON(addr >= end))
> - return -EINVAL;
> -
> - pgd = pgd_offset(mm, addr);
> - do {
> - next = pgd_addr_end(addr, end);
> - if (pgd_none_or_clear_bad(pgd))
> - continue;
> - err = apply_to_p4d_range(mm, pgd, addr, next, fn, data, false);
> - if (err)
> - break;
> - } while (pgd++, addr = next, addr != end);
> -
> - return err;
> + return __apply_to_page_range(mm, addr, size, fn, data, false);
> }
> EXPORT_SYMBOL_GPL(apply_to_existing_pages);
>
> _
>
>
> From: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Subject: mm-add-apply_to_existing_pages-helper-fix-fix
>
> s/apply_to_existing_pages/apply_to_existing_page_range/
>
> Cc: Daniel Axtens <dja@xxxxxxxxxx>
> Cc: Alexander Potapenko <glider@xxxxxxxxxx>
> Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
> Cc: Qian Cai <cai@xxxxxx>
> Cc: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> ---
>
> include/linux/mm.h | 6 +++---
> mm/memory.c | 6 +++---
> 2 files changed, 6 insertions(+), 6 deletions(-)
>
> --- a/include/linux/mm.h~mm-add-apply_to_existing_pages-helper-fix-fix
> +++ a/include/linux/mm.h
> @@ -2621,9 +2621,9 @@ static inline int vm_fault_to_errno(vm_f
> typedef int (*pte_fn_t)(pte_t *pte, unsigned long addr, void *data);
> extern int apply_to_page_range(struct mm_struct *mm, unsigned long address,
> unsigned long size, pte_fn_t fn, void *data);
> -extern int apply_to_existing_pages(struct mm_struct *mm, unsigned long address,
> - unsigned long size, pte_fn_t fn,
> - void *data);
> +extern int apply_to_existing_page_range(struct mm_struct *mm,
> + unsigned long address, unsigned long size,
> + pte_fn_t fn, void *data);
>
> #ifdef CONFIG_PAGE_POISONING
> extern bool page_poisoning_enabled(void);
> --- a/mm/memory.c~mm-add-apply_to_existing_pages-helper-fix-fix
> +++ a/mm/memory.c
> @@ -2184,12 +2184,12 @@ EXPORT_SYMBOL_GPL(apply_to_page_range);
> * Unlike apply_to_page_range, this does _not_ fill in page tables
> * where they are absent.
> */
> -int apply_to_existing_pages(struct mm_struct *mm, unsigned long addr,
> - unsigned long size, pte_fn_t fn, void *data)
> +int apply_to_existing_page_range(struct mm_struct *mm, unsigned long addr,
> + unsigned long size, pte_fn_t fn, void *data)
> {
> return __apply_to_page_range(mm, addr, size, fn, data, false);
> }
> -EXPORT_SYMBOL_GPL(apply_to_existing_pages);
> +EXPORT_SYMBOL_GPL(apply_to_existing_page_range);
>
> /*
> * handle_pte_fault chooses page fault handler according to an entry which was
> _
>
> From: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Subject: mm-add-apply_to_existing_pages-helper-fix-fix-fix
>
> initialize __apply_to_page_range::err
>
> Cc: Alexander Potapenko <glider@xxxxxxxxxx>
> Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
> Cc: Daniel Axtens <dja@xxxxxxxxxx>
> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
> Cc: Qian Cai <cai@xxxxxx>
> Cc: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> ---
>
> mm/memory.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> --- a/mm/memory.c~mm-add-apply_to_existing_pages-helper-fix-fix-fix
> +++ a/mm/memory.c
> @@ -2148,7 +2148,7 @@ static int __apply_to_page_range(struct
> pgd_t *pgd;
> unsigned long next;
> unsigned long end = addr + size;
> - int err;
> + int err = 0;
>
> if (WARN_ON(addr >= end))
> return -EINVAL;
> _
