[PATCH v4 03/15] asm-generic: pgalloc: Provide generic p4d_{alloc_one,free}
From: Qi Zheng <hidden>
Date: 2024-12-30 09:09:18
Also in:
linux-arch, linux-arm-kernel, linux-m68k, linux-mips, linux-mm, linux-riscv, linux-s390, linux-sh, linux-um, lkml, loongarch, sparclinux
Subsystem:
arm64 port (aarch64 architecture), generic include/asm header files, risc-v architecture, the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Catalin Marinas, Will Deacon, Arnd Bergmann, Paul Walmsley, Palmer Dabbelt, Albert Ou, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: Kevin Brodsky <redacted> Four architectures currently implement 5-level pgtables: arm64, riscv, x86 and s390. The first three have essentially the same implementation for p4d_alloc_one() and p4d_free(), so we've got an opportunity to reduce duplication like at the lower levels. Provide a generic version of p4d_alloc_one() and p4d_free(), and make use of it on those architectures. Their implementation is the same as at PUD level, except that p4d_free() performs a runtime check by calling mm_p4d_folded(). 5-level pgtables depend on a runtime-detected hardware feature on all supported architectures, so we might as well include this check in the generic implementation. No runtime check is required in p4d_alloc_one() as the top-level p4d_alloc() already does the required check. Signed-off-by: Kevin Brodsky <redacted> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Qi Zheng <redacted> --- arch/arm64/include/asm/pgalloc.h | 17 ------------ arch/riscv/include/asm/pgalloc.h | 23 ---------------- arch/x86/include/asm/pgalloc.h | 18 ------------- include/asm-generic/pgalloc.h | 45 ++++++++++++++++++++++++++++++++ 4 files changed, 45 insertions(+), 58 deletions(-)
diff --git a/arch/arm64/include/asm/pgalloc.h b/arch/arm64/include/asm/pgalloc.h
index e75422864d1bd..2965f5a7e39e3 100644
--- a/arch/arm64/include/asm/pgalloc.h
+++ b/arch/arm64/include/asm/pgalloc.h@@ -85,23 +85,6 @@ static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgdp, p4d_t *p4dp) __pgd_populate(pgdp, __pa(p4dp), pgdval); } -static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long addr) -{ - gfp_t gfp = GFP_PGTABLE_USER; - - if (mm == &init_mm) - gfp = GFP_PGTABLE_KERNEL; - return (p4d_t *)get_zeroed_page(gfp); -} - -static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d) -{ - if (!pgtable_l5_enabled()) - return; - BUG_ON((unsigned long)p4d & (PAGE_SIZE-1)); - free_page((unsigned long)p4d); -} - #define __p4d_free_tlb(tlb, p4d, addr) p4d_free((tlb)->mm, p4d) #else static inline void __pgd_populate(pgd_t *pgdp, phys_addr_t p4dp, pgdval_t prot)
diff --git a/arch/riscv/include/asm/pgalloc.h b/arch/riscv/include/asm/pgalloc.h
index 8ad0bbe838a24..551d614d3369c 100644
--- a/arch/riscv/include/asm/pgalloc.h
+++ b/arch/riscv/include/asm/pgalloc.h@@ -105,29 +105,6 @@ static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud, } } -#define p4d_alloc_one p4d_alloc_one -static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long addr) -{ - gfp_t gfp = GFP_PGTABLE_USER; - - if (mm == &init_mm) - gfp = GFP_PGTABLE_KERNEL; - return (p4d_t *)get_zeroed_page(gfp); -} - -static inline void __p4d_free(struct mm_struct *mm, p4d_t *p4d) -{ - BUG_ON((unsigned long)p4d & (PAGE_SIZE-1)); - free_page((unsigned long)p4d); -} - -#define p4d_free p4d_free -static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d) -{ - if (pgtable_l5_enabled) - __p4d_free(mm, p4d); -} - static inline void __p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d, unsigned long addr) {
diff --git a/arch/x86/include/asm/pgalloc.h b/arch/x86/include/asm/pgalloc.h
index dcd836b59bebd..dd4841231bb9f 100644
--- a/arch/x86/include/asm/pgalloc.h
+++ b/arch/x86/include/asm/pgalloc.h@@ -147,24 +147,6 @@ static inline void pgd_populate_safe(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4 set_pgd_safe(pgd, __pgd(_PAGE_TABLE | __pa(p4d))); } -static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long addr) -{ - gfp_t gfp = GFP_KERNEL_ACCOUNT; - - if (mm == &init_mm) - gfp &= ~__GFP_ACCOUNT; - return (p4d_t *)get_zeroed_page(gfp); -} - -static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d) -{ - if (!pgtable_l5_enabled()) - return; - - BUG_ON((unsigned long)p4d & (PAGE_SIZE-1)); - free_page((unsigned long)p4d); -} - extern void ___p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d); static inline void __p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d,
diff --git a/include/asm-generic/pgalloc.h b/include/asm-generic/pgalloc.h
index 7c48f5fbf8aa7..59131629ac9cc 100644
--- a/include/asm-generic/pgalloc.h
+++ b/include/asm-generic/pgalloc.h@@ -215,6 +215,51 @@ static inline void pud_free(struct mm_struct *mm, pud_t *pud) #endif /* CONFIG_PGTABLE_LEVELS > 3 */ +#if CONFIG_PGTABLE_LEVELS > 4 + +static inline p4d_t *__p4d_alloc_one_noprof(struct mm_struct *mm, unsigned long addr) +{ + gfp_t gfp = GFP_PGTABLE_USER; + struct ptdesc *ptdesc; + + if (mm == &init_mm) + gfp = GFP_PGTABLE_KERNEL; + gfp &= ~__GFP_HIGHMEM; + + ptdesc = pagetable_alloc_noprof(gfp, 0); + if (!ptdesc) + return NULL; + + return ptdesc_address(ptdesc); +} +#define __p4d_alloc_one(...) alloc_hooks(__p4d_alloc_one_noprof(__VA_ARGS__)) + +#ifndef __HAVE_ARCH_P4D_ALLOC_ONE +static inline p4d_t *p4d_alloc_one_noprof(struct mm_struct *mm, unsigned long addr) +{ + return __p4d_alloc_one_noprof(mm, addr); +} +#define p4d_alloc_one(...) alloc_hooks(p4d_alloc_one_noprof(__VA_ARGS__)) +#endif + +static inline void __p4d_free(struct mm_struct *mm, p4d_t *p4d) +{ + struct ptdesc *ptdesc = virt_to_ptdesc(p4d); + + BUG_ON((unsigned long)p4d & (PAGE_SIZE-1)); + pagetable_free(ptdesc); +} + +#ifndef __HAVE_ARCH_P4D_FREE +static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d) +{ + if (!mm_p4d_folded(mm)) + __p4d_free(mm, p4d); +} +#endif + +#endif /* CONFIG_PGTABLE_LEVELS > 4 */ + #ifndef __HAVE_ARCH_PGD_FREE static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd) {
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2.20.1