Subsequent patches will modify pte_alloc{,_map,_map_lock}(), which are the allocate function related to user PTE page table pages, so move those to a separate file in advance. This patch contains no functional changes, only some preparatory work. Signed-off-by: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx> --- arch/arm/mm/pgd.c | 1 + arch/arm64/mm/hugetlbpage.c | 1 + arch/ia64/mm/hugetlbpage.c | 1 + arch/parisc/mm/hugetlbpage.c | 1 + arch/powerpc/mm/hugetlbpage.c | 1 + arch/s390/mm/gmap.c | 1 + arch/s390/mm/pgtable.c | 1 + arch/sh/mm/hugetlbpage.c | 1 + arch/sparc/mm/hugetlbpage.c | 1 + include/linux/mm.h | 11 ---------- include/linux/pte_ref.h | 29 ++++++++++++++++++++++++++ mm/Makefile | 3 ++- mm/internal.h | 1 + mm/memory.c | 38 ---------------------------------- mm/pte_ref.c | 48 +++++++++++++++++++++++++++++++++++++++++++ 15 files changed, 89 insertions(+), 50 deletions(-) create mode 100644 include/linux/pte_ref.h create mode 100644 mm/pte_ref.c diff --git a/arch/arm/mm/pgd.c b/arch/arm/mm/pgd.c index f8e9bc58a84f..dcac1124e8bd 100644 --- a/arch/arm/mm/pgd.c +++ b/arch/arm/mm/pgd.c @@ -8,6 +8,7 @@ #include <linux/gfp.h> #include <linux/highmem.h> #include <linux/slab.h> +#include <linux/pte_ref.h> #include <asm/cp15.h> #include <asm/pgalloc.h> diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index 23505fc35324..6c8177647053 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -14,6 +14,7 @@ #include <linux/pagemap.h> #include <linux/err.h> #include <linux/sysctl.h> +#include <linux/pte_ref.h> #include <asm/mman.h> #include <asm/tlb.h> #include <asm/tlbflush.h> diff --git a/arch/ia64/mm/hugetlbpage.c b/arch/ia64/mm/hugetlbpage.c index f993cb36c062..d343639db1ad 100644 --- a/arch/ia64/mm/hugetlbpage.c +++ b/arch/ia64/mm/hugetlbpage.c @@ -17,6 +17,7 @@ #include <linux/module.h> #include <linux/sysctl.h> #include <linux/log2.h> +#include <linux/pte_ref.h> #include <asm/mman.h> #include <asm/tlb.h> #include <asm/tlbflush.h> diff --git a/arch/parisc/mm/hugetlbpage.c b/arch/parisc/mm/hugetlbpage.c index d1d3990b83f6..4f6044d6b4bd 100644 --- a/arch/parisc/mm/hugetlbpage.c +++ b/arch/parisc/mm/hugetlbpage.c @@ -13,6 +13,7 @@ #include <linux/hugetlb.h> #include <linux/pagemap.h> #include <linux/sysctl.h> +#include <linux/pte_ref.h> #include <asm/mman.h> #include <asm/tlb.h> diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c index 9a75ba078e1b..1afb8f552bcf 100644 --- a/arch/powerpc/mm/hugetlbpage.c +++ b/arch/powerpc/mm/hugetlbpage.c @@ -19,6 +19,7 @@ #include <linux/swap.h> #include <linux/swapops.h> #include <linux/kmemleak.h> +#include <linux/pte_ref.h> #include <asm/pgalloc.h> #include <asm/tlb.h> #include <asm/setup.h> diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c index 9bb2c7512cd5..c1826d74773a 100644 --- a/arch/s390/mm/gmap.c +++ b/arch/s390/mm/gmap.c @@ -18,6 +18,7 @@ #include <linux/ksm.h> #include <linux/mman.h> #include <linux/pgtable.h> +#include <linux/pte_ref.h> #include <asm/pgalloc.h> #include <asm/gmap.h> diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c index eec3a9d7176e..594a6d6888e3 100644 --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -18,6 +18,7 @@ #include <linux/sysctl.h> #include <linux/ksm.h> #include <linux/mman.h> +#include <linux/pte_ref.h> #include <asm/tlb.h> #include <asm/tlbflush.h> diff --git a/arch/sh/mm/hugetlbpage.c b/arch/sh/mm/hugetlbpage.c index 999ab5916e69..6a593ab248b7 100644 --- a/arch/sh/mm/hugetlbpage.c +++ b/arch/sh/mm/hugetlbpage.c @@ -15,6 +15,7 @@ #include <linux/hugetlb.h> #include <linux/pagemap.h> #include <linux/sysctl.h> +#include <linux/pte_ref.h> #include <asm/mman.h> #include <asm/tlb.h> diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c index 0f49fada2093..4b9119825264 100644 --- a/arch/sparc/mm/hugetlbpage.c +++ b/arch/sparc/mm/hugetlbpage.c @@ -11,6 +11,7 @@ #include <linux/hugetlb.h> #include <linux/pagemap.h> #include <linux/sysctl.h> +#include <linux/pte_ref.h> #include <asm/mman.h> #include <asm/pgalloc.h> diff --git a/include/linux/mm.h b/include/linux/mm.h index 57e48217bd71..369d4283de49 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2245,7 +2245,6 @@ static inline void mm_inc_nr_ptes(struct mm_struct *mm) {} static inline void mm_dec_nr_ptes(struct mm_struct *mm) {} #endif -int __pte_alloc(struct mm_struct *mm, pmd_t *pmd); int __pte_alloc_kernel(pmd_t *pmd); #if defined(CONFIG_MMU) @@ -2371,15 +2370,6 @@ static inline void pgtable_pte_page_dtor(struct page *page) pte_unmap(pte); \ } while (0) -#define pte_alloc(mm, pmd) (unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, pmd)) - -#define pte_alloc_map(mm, pmd, address) \ - (pte_alloc(mm, pmd) ? NULL : pte_offset_map(pmd, address)) - -#define pte_alloc_map_lock(mm, pmd, address, ptlp) \ - (pte_alloc(mm, pmd) ? \ - NULL : pte_offset_map_lock(mm, pmd, address, ptlp)) - #define pte_alloc_kernel(pmd, address) \ ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd))? \ NULL: pte_offset_kernel(pmd, address)) @@ -2471,7 +2461,6 @@ static inline spinlock_t *pud_lock(struct mm_struct *mm, pud_t *pud) return ptl; } -extern void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte); extern void __init pagecache_init(void); extern void __init free_area_init_memoryless_node(int nid); extern void free_initmem(void); diff --git a/include/linux/pte_ref.h b/include/linux/pte_ref.h new file mode 100644 index 000000000000..60b752dd7846 --- /dev/null +++ b/include/linux/pte_ref.h @@ -0,0 +1,29 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Free user PTE page table pages + * + * Copyright (c) 2021, ByteDance. All rights reserved. + * + * Author: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx> + */ +#ifndef _LINUX_PTE_REF_H +#define _LINUX_PTE_REF_H + +#include <linux/mm.h> +#include <linux/pgtable.h> +#include <asm/pgalloc.h> + +void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte); +int __pte_alloc(struct mm_struct *mm, pmd_t *pmd); + +#define pte_alloc(mm, pmd) (unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, pmd)) + +#define pte_alloc_map(mm, pmd, address) \ + (pte_alloc(mm, pmd) ? NULL : pte_offset_map(pmd, address)) + +#define pte_alloc_map_lock(mm, pmd, address, ptlp) \ + (pte_alloc(mm, pmd) ? \ + NULL : pte_offset_map_lock(mm, pmd, address, ptlp)) + +#endif + diff --git a/mm/Makefile b/mm/Makefile index 970604ea97dd..5cdbfaa2a7b5 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -38,7 +38,8 @@ mmu-y := nommu.o mmu-$(CONFIG_MMU) := highmem.o memory.o mincore.o \ mlock.o mmap.o mmu_gather.o mprotect.o mremap.o \ msync.o page_vma_mapped.o pagewalk.o \ - pgtable-generic.o rmap.o vmalloc.o ioremap.o + pgtable-generic.o rmap.o vmalloc.o ioremap.o \ + pte_ref.o ifdef CONFIG_CROSS_MEMORY_ATTACH diff --git a/mm/internal.h b/mm/internal.h index b1001ebeb286..c1e23fa563a7 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -11,6 +11,7 @@ #include <linux/mm.h> #include <linux/pagemap.h> #include <linux/tracepoint-defs.h> +#include <linux/pte_ref.h> /* * The set of flags that only affect watermark checking and reclaim diff --git a/mm/memory.c b/mm/memory.c index d2aaa85b840c..265b841cc7f9 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -433,44 +433,6 @@ void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *vma, } } -void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte) -{ - spinlock_t *ptl = pmd_lock(mm, pmd); - - if (likely(pmd_none(*pmd))) { /* Has another populated it ? */ - mm_inc_nr_ptes(mm); - /* - * Ensure all pte setup (eg. pte page lock and page clearing) are - * visible before the pte is made visible to other CPUs by being - * put into page tables. - * - * The other side of the story is the pointer chasing in the page - * table walking code (when walking the page table without locking; - * ie. most of the time). Fortunately, these data accesses consist - * of a chain of data-dependent loads, meaning most CPUs (alpha - * being the notable exception) will already guarantee loads are - * seen in-order. See the alpha page table accessors for the - * smp_rmb() barriers in page table walking code. - */ - smp_wmb(); /* Could be smp_wmb__xxx(before|after)_spin_lock */ - pmd_populate(mm, pmd, *pte); - *pte = NULL; - } - spin_unlock(ptl); -} - -int __pte_alloc(struct mm_struct *mm, pmd_t *pmd) -{ - pgtable_t new = pte_alloc_one(mm); - if (!new) - return -ENOMEM; - - pmd_install(mm, pmd, &new); - if (new) - pte_free(mm, new); - return 0; -} - int __pte_alloc_kernel(pmd_t *pmd) { pte_t *new = pte_alloc_one_kernel(&init_mm); diff --git a/mm/pte_ref.c b/mm/pte_ref.c new file mode 100644 index 000000000000..07a73b5521cc --- /dev/null +++ b/mm/pte_ref.c @@ -0,0 +1,48 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Free user PTE page table pages + * + * Copyright (c) 2021, ByteDance. All rights reserved. + * + * Author: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx> + */ + +#include <linux/pte_ref.h> + +void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte) +{ + spinlock_t *ptl = pmd_lock(mm, pmd); + + if (likely(pmd_none(*pmd))) { /* Has another populated it ? */ + mm_inc_nr_ptes(mm); + /* + * Ensure all pte setup (eg. pte page lock and page clearing) are + * visible before the pte is made visible to other CPUs by being + * put into page tables. + * + * The other side of the story is the pointer chasing in the page + * table walking code (when walking the page table without locking; + * ie. most of the time). Fortunately, these data accesses consist + * of a chain of data-dependent loads, meaning most CPUs (alpha + * being the notable exception) will already guarantee loads are + * seen in-order. See the alpha page table accessors for the + * smp_rmb() barriers in page table walking code. + */ + smp_wmb(); /* Could be smp_wmb__xxx(before|after)_spin_lock */ + pmd_populate(mm, pmd, *pte); + *pte = NULL; + } + spin_unlock(ptl); +} + +int __pte_alloc(struct mm_struct *mm, pmd_t *pmd) +{ + pgtable_t new = pte_alloc_one(mm); + if (!new) + return -ENOMEM; + + pmd_install(mm, pmd, &new); + if (new) + pte_free(mm, new); + return 0; +} -- 2.11.0