[v4,09/36] arm64: Implement the new page table range API
Commit Message
Add set_ptes(), update_mmu_cache_range() and flush_dcache_folio().
Change the PG_dcache_clean flag from being per-page to per-folio.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
---
arch/arm64/include/asm/cacheflush.h | 4 +++-
arch/arm64/include/asm/pgtable.h | 25 ++++++++++++++------
arch/arm64/mm/flush.c | 36 +++++++++++------------------
3 files changed, 35 insertions(+), 30 deletions(-)
Comments
On Wed, Mar 15, 2023 at 05:14:17AM +0000, Matthew Wilcox (Oracle) wrote:
> Add set_ptes(), update_mmu_cache_range() and flush_dcache_folio().
> Change the PG_dcache_clean flag from being per-page to per-folio.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
> Cc: linux-arm-kernel@lists.infradead.org
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
> ---
> arch/arm64/include/asm/cacheflush.h | 4 +++-
> arch/arm64/include/asm/pgtable.h | 25 ++++++++++++++------
> arch/arm64/mm/flush.c | 36 +++++++++++------------------
> 3 files changed, 35 insertions(+), 30 deletions(-)
>
> diff --git a/arch/arm64/include/asm/cacheflush.h b/arch/arm64/include/asm/cacheflush.h
> index 37185e978aeb..d115451ed263 100644
> --- a/arch/arm64/include/asm/cacheflush.h
> +++ b/arch/arm64/include/asm/cacheflush.h
> @@ -114,7 +114,7 @@ extern void copy_to_user_page(struct vm_area_struct *, struct page *,
> #define copy_to_user_page copy_to_user_page
>
> /*
> - * flush_dcache_page is used when the kernel has written to the page
> + * flush_dcache_folio is used when the kernel has written to the page
> * cache page at virtual address page->virtual.
> *
> * If this page isn't mapped (ie, page_mapping == NULL), or it might
> @@ -127,6 +127,8 @@ extern void copy_to_user_page(struct vm_area_struct *, struct page *,
> */
> #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
> extern void flush_dcache_page(struct page *);
> +void flush_dcache_folio(struct folio *);
> +#define flush_dcache_folio flush_dcache_folio
>
> static __always_inline void icache_inval_all_pou(void)
> {
> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
> index 9428748f4691..6fd012663a01 100644
> --- a/arch/arm64/include/asm/pgtable.h
> +++ b/arch/arm64/include/asm/pgtable.h
> @@ -355,12 +355,21 @@ static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
> set_pte(ptep, pte);
> }
>
> -static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
> - pte_t *ptep, pte_t pte)
> -{
> - page_table_check_ptes_set(mm, addr, ptep, pte, 1);
> - return __set_pte_at(mm, addr, ptep, pte);
> +static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
> + pte_t *ptep, pte_t pte, unsigned int nr)
> +{
> + page_table_check_ptes_set(mm, addr, ptep, pte, nr);
> +
> + for (;;) {
> + __set_pte_at(mm, addr, ptep, pte);
> + if (--nr == 0)
> + break;
> + ptep++;
> + addr += PAGE_SIZE;
> + pte_val(pte) += PAGE_SIZE;
> + }
> }
> +#define set_ptes set_ptes
>
> /*
> * Huge pte definitions.
> @@ -1059,8 +1068,8 @@ static inline void arch_swap_restore(swp_entry_t entry, struct folio *folio)
> /*
> * On AArch64, the cache coherency is handled via the set_pte_at() function.
> */
> -static inline void update_mmu_cache(struct vm_area_struct *vma,
> - unsigned long addr, pte_t *ptep)
> +static inline void update_mmu_cache_range(struct vm_area_struct *vma,
> + unsigned long addr, pte_t *ptep, unsigned int nr)
> {
> /*
> * We don't do anything here, so there's a very small chance of
> @@ -1069,6 +1078,8 @@ static inline void update_mmu_cache(struct vm_area_struct *vma,
> */
> }
>
> +#define update_mmu_cache(vma, addr, ptep) \
> + update_mmu_cache_range(vma, addr, ptep, 1)
> #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
>
> #ifdef CONFIG_ARM64_PA_BITS_52
> diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c
> index 5f9379b3c8c8..deb781af0a3a 100644
> --- a/arch/arm64/mm/flush.c
> +++ b/arch/arm64/mm/flush.c
> @@ -50,20 +50,13 @@ void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
>
> void __sync_icache_dcache(pte_t pte)
> {
> - struct page *page = pte_page(pte);
> + struct folio *folio = page_folio(pte_page(pte));
>
> - /*
> - * HugeTLB pages are always fully mapped, so only setting head page's
> - * PG_dcache_clean flag is enough.
> - */
> - if (PageHuge(page))
> - page = compound_head(page);
> -
> - if (!test_bit(PG_dcache_clean, &page->flags)) {
> - sync_icache_aliases((unsigned long)page_address(page),
> - (unsigned long)page_address(page) +
> - page_size(page));
> - set_bit(PG_dcache_clean, &page->flags);
> + if (!test_bit(PG_dcache_clean, &folio->flags)) {
> + sync_icache_aliases((unsigned long)folio_address(folio),
> + (unsigned long)folio_address(folio) +
> + folio_size(folio));
> + set_bit(PG_dcache_clean, &folio->flags);
> }
> }
> EXPORT_SYMBOL_GPL(__sync_icache_dcache);
> @@ -73,17 +66,16 @@ EXPORT_SYMBOL_GPL(__sync_icache_dcache);
> * it as dirty for later flushing when mapped in user space (if executable,
> * see __sync_icache_dcache).
> */
> -void flush_dcache_page(struct page *page)
> +void flush_dcache_folio(struct folio *folio)
> {
> - /*
> - * HugeTLB pages are always fully mapped and only head page will be
> - * set PG_dcache_clean (see comments in __sync_icache_dcache()).
> - */
> - if (PageHuge(page))
> - page = compound_head(page);
> + if (test_bit(PG_dcache_clean, &folio->flags))
> + clear_bit(PG_dcache_clean, &folio->flags);
> +}
> +EXPORT_SYMBOL(flush_dcache_folio);
>
> - if (test_bit(PG_dcache_clean, &page->flags))
> - clear_bit(PG_dcache_clean, &page->flags);
> +void flush_dcache_page(struct page *page)
> +{
> + flush_dcache_folio(page_folio(page));
> }
> EXPORT_SYMBOL(flush_dcache_page);
>
> --
> 2.39.2
>
>
On 3/15/23 10:44, Matthew Wilcox (Oracle) wrote:
> Add set_ptes(), update_mmu_cache_range() and flush_dcache_folio().
> Change the PG_dcache_clean flag from being per-page to per-folio.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
> Cc: linux-arm-kernel@lists.infradead.org
> ---
> arch/arm64/include/asm/cacheflush.h | 4 +++-
> arch/arm64/include/asm/pgtable.h | 25 ++++++++++++++------
> arch/arm64/mm/flush.c | 36 +++++++++++------------------
> 3 files changed, 35 insertions(+), 30 deletions(-)
>
> diff --git a/arch/arm64/include/asm/cacheflush.h b/arch/arm64/include/asm/cacheflush.h
> index 37185e978aeb..d115451ed263 100644
> --- a/arch/arm64/include/asm/cacheflush.h
> +++ b/arch/arm64/include/asm/cacheflush.h
> @@ -114,7 +114,7 @@ extern void copy_to_user_page(struct vm_area_struct *, struct page *,
> #define copy_to_user_page copy_to_user_page
>
> /*
> - * flush_dcache_page is used when the kernel has written to the page
> + * flush_dcache_folio is used when the kernel has written to the page
> * cache page at virtual address page->virtual.
> *
> * If this page isn't mapped (ie, page_mapping == NULL), or it might
> @@ -127,6 +127,8 @@ extern void copy_to_user_page(struct vm_area_struct *, struct page *,
> */
> #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
> extern void flush_dcache_page(struct page *);
> +void flush_dcache_folio(struct folio *);
This is giving a checkpatch.pl warning
WARNING: function definition argument 'struct folio *' should also have an identifier name
#36: FILE: arch/arm64/include/asm/cacheflush.h:130:
+void flush_dcache_folio(struct folio *);
total: 0 errors, 1 warnings, 111 lines checked
> +#define flush_dcache_folio flush_dcache_folio
>
> static __always_inline void icache_inval_all_pou(void)
> {
> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
> index 9428748f4691..6fd012663a01 100644
> --- a/arch/arm64/include/asm/pgtable.h
> +++ b/arch/arm64/include/asm/pgtable.h
> @@ -355,12 +355,21 @@ static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
> set_pte(ptep, pte);
> }
>
> -static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
> - pte_t *ptep, pte_t pte)
> -{
> - page_table_check_ptes_set(mm, addr, ptep, pte, 1);
> - return __set_pte_at(mm, addr, ptep, pte);
> +static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
> + pte_t *ptep, pte_t pte, unsigned int nr)
> +{
> + page_table_check_ptes_set(mm, addr, ptep, pte, nr);
> +
> + for (;;) {
> + __set_pte_at(mm, addr, ptep, pte);
> + if (--nr == 0)
> + break;
> + ptep++;
> + addr += PAGE_SIZE;
> + pte_val(pte) += PAGE_SIZE;
> + }
> }
> +#define set_ptes set_ptes
>
> /*
> * Huge pte definitions.
> @@ -1059,8 +1068,8 @@ static inline void arch_swap_restore(swp_entry_t entry, struct folio *folio)
> /*
> * On AArch64, the cache coherency is handled via the set_pte_at() function.
> */
> -static inline void update_mmu_cache(struct vm_area_struct *vma,
> - unsigned long addr, pte_t *ptep)
> +static inline void update_mmu_cache_range(struct vm_area_struct *vma,
> + unsigned long addr, pte_t *ptep, unsigned int nr)
> {
> /*
> * We don't do anything here, so there's a very small chance of
> @@ -1069,6 +1078,8 @@ static inline void update_mmu_cache(struct vm_area_struct *vma,
> */
> }
>
> +#define update_mmu_cache(vma, addr, ptep) \
> + update_mmu_cache_range(vma, addr, ptep, 1)
> #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
>
> #ifdef CONFIG_ARM64_PA_BITS_52
> diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c
> index 5f9379b3c8c8..deb781af0a3a 100644
> --- a/arch/arm64/mm/flush.c
> +++ b/arch/arm64/mm/flush.c
> @@ -50,20 +50,13 @@ void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
>
> void __sync_icache_dcache(pte_t pte)
> {
> - struct page *page = pte_page(pte);
> + struct folio *folio = page_folio(pte_page(pte));
>
> - /*
> - * HugeTLB pages are always fully mapped, so only setting head page's
> - * PG_dcache_clean flag is enough.
> - */
> - if (PageHuge(page))
> - page = compound_head(page);
> -
> - if (!test_bit(PG_dcache_clean, &page->flags)) {
> - sync_icache_aliases((unsigned long)page_address(page),
> - (unsigned long)page_address(page) +
> - page_size(page));
> - set_bit(PG_dcache_clean, &page->flags);
> + if (!test_bit(PG_dcache_clean, &folio->flags)) {
> + sync_icache_aliases((unsigned long)folio_address(folio),
> + (unsigned long)folio_address(folio) +
> + folio_size(folio));
> + set_bit(PG_dcache_clean, &folio->flags);
> }
> }
> EXPORT_SYMBOL_GPL(__sync_icache_dcache);
> @@ -73,17 +66,16 @@ EXPORT_SYMBOL_GPL(__sync_icache_dcache);
> * it as dirty for later flushing when mapped in user space (if executable,
> * see __sync_icache_dcache).
> */
> -void flush_dcache_page(struct page *page)
> +void flush_dcache_folio(struct folio *folio)
> {
> - /*
> - * HugeTLB pages are always fully mapped and only head page will be
> - * set PG_dcache_clean (see comments in __sync_icache_dcache()).
> - */
> - if (PageHuge(page))
> - page = compound_head(page);
> + if (test_bit(PG_dcache_clean, &folio->flags))
> + clear_bit(PG_dcache_clean, &folio->flags);
> +}
> +EXPORT_SYMBOL(flush_dcache_folio);
>
> - if (test_bit(PG_dcache_clean, &page->flags))
> - clear_bit(PG_dcache_clean, &page->flags);
> +void flush_dcache_page(struct page *page)
> +{
> + flush_dcache_folio(page_folio(page));
> }
> EXPORT_SYMBOL(flush_dcache_page);
>
Otherwise LGTM.
On Thu, May 25, 2023 at 09:05:35AM +0530, Anshuman Khandual wrote:
> > @@ -127,6 +127,8 @@ extern void copy_to_user_page(struct vm_area_struct *, struct page *,
> > */
> > #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
> > extern void flush_dcache_page(struct page *);
> > +void flush_dcache_folio(struct folio *);
>
> This is giving a checkpatch.pl warning
>
> WARNING: function definition argument 'struct folio *' should also have an identifier name
> #36: FILE: arch/arm64/include/asm/cacheflush.h:130:
> +void flush_dcache_folio(struct folio *);
Yes, but checkpatch is *stupid*. Don't just follow tools blindly.
How is naming the parameter here helping anyone?
On 5/25/23 09:35, Matthew Wilcox wrote:
> On Thu, May 25, 2023 at 09:05:35AM +0530, Anshuman Khandual wrote:
>>> @@ -127,6 +127,8 @@ extern void copy_to_user_page(struct vm_area_struct *, struct page *,
>>> */
>>> #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
>>> extern void flush_dcache_page(struct page *);
>>> +void flush_dcache_folio(struct folio *);
>>
>> This is giving a checkpatch.pl warning
>>
>> WARNING: function definition argument 'struct folio *' should also have an identifier name
>> #36: FILE: arch/arm64/include/asm/cacheflush.h:130:
>> +void flush_dcache_folio(struct folio *);
>
> Yes, but checkpatch is *stupid*. Don't just follow tools blindly.
> How is naming the parameter here helping anyone?
Agreed, it seemed bit weird. Never mind.
@@ -114,7 +114,7 @@ extern void copy_to_user_page(struct vm_area_struct *, struct page *,
#define copy_to_user_page copy_to_user_page
/*
- * flush_dcache_page is used when the kernel has written to the page
+ * flush_dcache_folio is used when the kernel has written to the page
* cache page at virtual address page->virtual.
*
* If this page isn't mapped (ie, page_mapping == NULL), or it might
@@ -127,6 +127,8 @@ extern void copy_to_user_page(struct vm_area_struct *, struct page *,
*/
#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
extern void flush_dcache_page(struct page *);
+void flush_dcache_folio(struct folio *);
+#define flush_dcache_folio flush_dcache_folio
static __always_inline void icache_inval_all_pou(void)
{
@@ -355,12 +355,21 @@ static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
set_pte(ptep, pte);
}
-static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, pte_t pte)
-{
- page_table_check_ptes_set(mm, addr, ptep, pte, 1);
- return __set_pte_at(mm, addr, ptep, pte);
+static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte, unsigned int nr)
+{
+ page_table_check_ptes_set(mm, addr, ptep, pte, nr);
+
+ for (;;) {
+ __set_pte_at(mm, addr, ptep, pte);
+ if (--nr == 0)
+ break;
+ ptep++;
+ addr += PAGE_SIZE;
+ pte_val(pte) += PAGE_SIZE;
+ }
}
+#define set_ptes set_ptes
/*
* Huge pte definitions.
@@ -1059,8 +1068,8 @@ static inline void arch_swap_restore(swp_entry_t entry, struct folio *folio)
/*
* On AArch64, the cache coherency is handled via the set_pte_at() function.
*/
-static inline void update_mmu_cache(struct vm_area_struct *vma,
- unsigned long addr, pte_t *ptep)
+static inline void update_mmu_cache_range(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *ptep, unsigned int nr)
{
/*
* We don't do anything here, so there's a very small chance of
@@ -1069,6 +1078,8 @@ static inline void update_mmu_cache(struct vm_area_struct *vma,
*/
}
+#define update_mmu_cache(vma, addr, ptep) \
+ update_mmu_cache_range(vma, addr, ptep, 1)
#define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
#ifdef CONFIG_ARM64_PA_BITS_52
@@ -50,20 +50,13 @@ void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
void __sync_icache_dcache(pte_t pte)
{
- struct page *page = pte_page(pte);
+ struct folio *folio = page_folio(pte_page(pte));
- /*
- * HugeTLB pages are always fully mapped, so only setting head page's
- * PG_dcache_clean flag is enough.
- */
- if (PageHuge(page))
- page = compound_head(page);
-
- if (!test_bit(PG_dcache_clean, &page->flags)) {
- sync_icache_aliases((unsigned long)page_address(page),
- (unsigned long)page_address(page) +
- page_size(page));
- set_bit(PG_dcache_clean, &page->flags);
+ if (!test_bit(PG_dcache_clean, &folio->flags)) {
+ sync_icache_aliases((unsigned long)folio_address(folio),
+ (unsigned long)folio_address(folio) +
+ folio_size(folio));
+ set_bit(PG_dcache_clean, &folio->flags);
}
}
EXPORT_SYMBOL_GPL(__sync_icache_dcache);
@@ -73,17 +66,16 @@ EXPORT_SYMBOL_GPL(__sync_icache_dcache);
* it as dirty for later flushing when mapped in user space (if executable,
* see __sync_icache_dcache).
*/
-void flush_dcache_page(struct page *page)
+void flush_dcache_folio(struct folio *folio)
{
- /*
- * HugeTLB pages are always fully mapped and only head page will be
- * set PG_dcache_clean (see comments in __sync_icache_dcache()).
- */
- if (PageHuge(page))
- page = compound_head(page);
+ if (test_bit(PG_dcache_clean, &folio->flags))
+ clear_bit(PG_dcache_clean, &folio->flags);
+}
+EXPORT_SYMBOL(flush_dcache_folio);
- if (test_bit(PG_dcache_clean, &page->flags))
- clear_bit(PG_dcache_clean, &page->flags);
+void flush_dcache_page(struct page *page)
+{
+ flush_dcache_folio(page_folio(page));
}
EXPORT_SYMBOL(flush_dcache_page);