From: Mike Rapoport <rppt@xxxxxxxxxxxxx> Subject: arm64: switch to generic version of pte allocation The PTE allocations in arm64 are identical to the generic ones modulo the GFP flags. Using the generic pte_alloc_one() functions ensures that the user page tables are allocated with __GFP_ACCOUNT set. The arm64 definition of PGALLOC_GFP is removed and replaced with GFP_PGTABLE_USER for p[gum]d_alloc_one() for the user page tables and GFP_PGTABLE_KERNEL for the kernel page tables. The KVM memory cache is now using GFP_PGTABLE_USER. The mappings created with create_pgd_mapping() are now using GFP_PGTABLE_KERNEL. The conversion to the generic version of pte_free_kernel() removes the NULL check for pte. The pte_free() version on arm64 is identical to the generic one and can be simply dropped. [cai@xxxxxx: fix a bogus GFP flag in pgd_alloc()] Link: http://lkml.kernel.org/r/1559656836-24940-1-git-send-email-cai@xxxxxx Link: http://lkml.kernel.org/r/1557296232-15361-5-git-send-email-rppt@xxxxxxxxxxxxx Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> Cc: Albert Ou <aou@xxxxxxxxxxxxxxxxx> Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx> Cc: Anton Ivanov <anton.ivanov@xxxxxxxxxxxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> Cc: Greentime Hu <green.hu@xxxxxxxxx> Cc: Guan Xuetao <gxt@xxxxxxxxxx> Cc: Guo Ren <guoren@xxxxxxxxxx> Cc: Guo Ren <ren_guo@xxxxxxxxx> Cc: Helge Deller <deller@xxxxxx> Cc: Ley Foon Tan <lftan@xxxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Matt Turner <mattst88@xxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Palmer Dabbelt <palmer@xxxxxxxxxx> Cc: Paul Burton <paul.burton@xxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Cc: Richard Kuo <rkuo@xxxxxxxxxxxxxx> Cc: Richard Weinberger <richard@xxxxxx> Cc: Russell King <linux@xxxxxxxxxxxxxxx> Cc: Sam Creasey <sammy@xxxxxxxxx> Cc: Vincent Chen <deanbo422@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/arm64/include/asm/pgalloc.h | 47 ++++------------------------- arch/arm64/mm/mmu.c | 2 - arch/arm64/mm/pgd.c | 9 ++++- virt/kvm/arm/mmu.c | 2 - 4 files changed, 17 insertions(+), 43 deletions(-) --- a/arch/arm64/include/asm/pgalloc.h~arm64-switch-to-generic-version-of-pte-allocation +++ a/arch/arm64/include/asm/pgalloc.h @@ -13,18 +13,23 @@ #include <asm/cacheflush.h> #include <asm/tlbflush.h> +#include <asm-generic/pgalloc.h> /* for pte_{alloc,free}_one */ + #define check_pgt_cache() do { } while (0) -#define PGALLOC_GFP (GFP_KERNEL | __GFP_ZERO) #define PGD_SIZE (PTRS_PER_PGD * sizeof(pgd_t)) #if CONFIG_PGTABLE_LEVELS > 2 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr) { + gfp_t gfp = GFP_PGTABLE_USER; struct page *page; - page = alloc_page(PGALLOC_GFP); + if (mm == &init_mm) + gfp = GFP_PGTABLE_KERNEL; + + page = alloc_page(gfp); if (!page) return NULL; if (!pgtable_pmd_page_ctor(page)) { @@ -61,7 +66,7 @@ static inline void __pud_populate(pud_t static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr) { - return (pud_t *)__get_free_page(PGALLOC_GFP); + return (pud_t *)__get_free_page(GFP_PGTABLE_USER); } static inline void pud_free(struct mm_struct *mm, pud_t *pudp) @@ -89,42 +94,6 @@ static inline void __pgd_populate(pgd_t extern pgd_t *pgd_alloc(struct mm_struct *mm); extern void pgd_free(struct mm_struct *mm, pgd_t *pgdp); -static inline pte_t * -pte_alloc_one_kernel(struct mm_struct *mm) -{ - return (pte_t *)__get_free_page(PGALLOC_GFP); -} - -static inline pgtable_t -pte_alloc_one(struct mm_struct *mm) -{ - struct page *pte; - - pte = alloc_pages(PGALLOC_GFP, 0); - if (!pte) - return NULL; - if (!pgtable_page_ctor(pte)) { - __free_page(pte); - return NULL; - } - return pte; -} - -/* - * Free a PTE table. - */ -static inline void pte_free_kernel(struct mm_struct *mm, pte_t *ptep) -{ - if (ptep) - free_page((unsigned long)ptep); -} - -static inline void pte_free(struct mm_struct *mm, pgtable_t pte) -{ - pgtable_page_dtor(pte); - __free_page(pte); -} - static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t ptep, pmdval_t prot) { --- a/arch/arm64/mm/mmu.c~arm64-switch-to-generic-version-of-pte-allocation +++ a/arch/arm64/mm/mmu.c @@ -362,7 +362,7 @@ static void __create_pgd_mapping(pgd_t * static phys_addr_t __pgd_pgtable_alloc(int shift) { - void *ptr = (void *)__get_free_page(PGALLOC_GFP); + void *ptr = (void *)__get_free_page(GFP_PGTABLE_KERNEL); BUG_ON(!ptr); /* Ensure the zeroed page is visible to the page table walker */ --- a/arch/arm64/mm/pgd.c~arm64-switch-to-generic-version-of-pte-allocation +++ a/arch/arm64/mm/pgd.c @@ -19,10 +19,15 @@ static struct kmem_cache *pgd_cache __ro pgd_t *pgd_alloc(struct mm_struct *mm) { + gfp_t gfp = GFP_PGTABLE_USER; + + if (unlikely(mm == &init_mm)) + gfp = GFP_PGTABLE_KERNEL; + if (PGD_SIZE == PAGE_SIZE) - return (pgd_t *)__get_free_page(PGALLOC_GFP); + return (pgd_t *)__get_free_page(gfp); else - return kmem_cache_alloc(pgd_cache, PGALLOC_GFP); + return kmem_cache_alloc(pgd_cache, GFP_PGTABLE_KERNEL); } void pgd_free(struct mm_struct *mm, pgd_t *pgd) --- a/virt/kvm/arm/mmu.c~arm64-switch-to-generic-version-of-pte-allocation +++ a/virt/kvm/arm/mmu.c @@ -129,7 +129,7 @@ static int mmu_topup_memory_cache(struct if (cache->nobjs >= min) return 0; while (cache->nobjs < max) { - page = (void *)__get_free_page(PGALLOC_GFP); + page = (void *)__get_free_page(GFP_PGTABLE_USER); if (!page) return -ENOMEM; cache->objects[cache->nobjs++] = page; _
