The patch titled
Subject: asm-generic: pgalloc: provide generic p4d_{alloc_one,free}
has been added to the -mm mm-unstable branch. Its filename is
asm-generic-pgalloc-provide-generic-p4d_alloc_onefree.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/asm-generic-pgalloc-provide-generic-p4d_alloc_onefree.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Kevin Brodsky <kevin.brodsky@xxxxxxx>
Subject: asm-generic: pgalloc: provide generic p4d_{alloc_one,free}
Date: Mon, 23 Dec 2024 17:40:49 +0800
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.
Link: https://lkml.kernel.org/r/4c4bcc1aa565c6252183553aecd5e5cbd1a0f6ea.1734945104.git.zhengqi.arch@xxxxxxxxxxxxx
Signed-off-by: Kevin Brodsky <kevin.brodsky@xxxxxxx>
Signed-off-by: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>
Acked-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Cc: Aneesh Kumar K.V (Arm) <aneesh.kumar@xxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Jann Horn <jannh@xxxxxxxxxx>
Cc: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx>
Cc: Muchun Song <muchun.song@xxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Ryan Roberts <ryan.roberts@xxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Yu Zhao <yuzhao@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
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(-)
--- a/arch/arm64/include/asm/pgalloc.h~asm-generic-pgalloc-provide-generic-p4d_alloc_onefree
+++ a/arch/arm64/include/asm/pgalloc.h
@@ -85,23 +85,6 @@ static inline void pgd_populate(struct m
__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)
--- a/arch/riscv/include/asm/pgalloc.h~asm-generic-pgalloc-provide-generic-p4d_alloc_onefree
+++ a/arch/riscv/include/asm/pgalloc.h
@@ -105,29 +105,6 @@ static inline void __pud_free_tlb(struct
}
}
-#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)
{
--- a/arch/x86/include/asm/pgalloc.h~asm-generic-pgalloc-provide-generic-p4d_alloc_onefree
+++ a/arch/x86/include/asm/pgalloc.h
@@ -147,24 +147,6 @@ static inline void pgd_populate_safe(str
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,
--- a/include/asm-generic/pgalloc.h~asm-generic-pgalloc-provide-generic-p4d_alloc_onefree
+++ a/include/asm-generic/pgalloc.h
@@ -215,6 +215,51 @@ static inline void pud_free(struct mm_st
#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)
{
_
Patches currently in -mm which might be from kevin.brodsky@xxxxxxx are
selftests-mm-fix-condition-in-uffd_move_test_common.patch
selftests-mm-fix-wmaybe-uninitialized-warnings.patch
selftests-mm-fix-strncpy-length.patch
selftests-mm-fix-warray-bounds-warnings-in-pkey_sighandler_tests.patch
selftests-mm-fix-warray-bounds-warnings-in-pkey_sighandler_tests-fix.patch
selftests-mm-build-with-o2.patch
selftests-mm-remove-unused-pkey-helpers.patch
selftests-mm-define-types-using-typedef-in-pkey-helpersh.patch
selftests-mm-ensure-pkey-h-define-inline-functions-only.patch
selftests-mm-remove-empty-pkey-helper-definition.patch
selftests-mm-ensure-non-global-pkey-symbols-are-marked-static.patch
selftests-mm-use-sys_pkey-helpers-consistently.patch
selftests-mm-use-sys_pkey-helpers-consistently-fix.patch
selftests-mm-rename-pkey-register-macro.patch
selftests-mm-skip-pkey_sighandler_tests-if-support-is-missing.patch
selftests-mm-remove-x-permission-from-sigaltstack-mapping.patch
riscv-mm-skip-pgtable-level-check-in-pudp4d_alloc_one.patch
asm-generic-pgalloc-provide-generic-p4d_alloc_onefree.patch
