From b9820d8f39f816b67112eb7ec5cdc4c1655ff060 Mon Sep 17 00:00:00 2001 From: Toshi Kani Date: Tue, 14 Apr 2015 15:47:26 -0700 Subject: [PATCH] mm: change vunmap to tear down huge KVA mappings Change vunmap_pmd_range() and vunmap_pud_range() to tear down huge KVA mappings when they are set. pud_clear_huge() and pmd_clear_huge() return zero when no-operation is performed, i.e. huge page mapping was not used. These changes are only enabled when CONFIG_HAVE_ARCH_HUGE_VMAP is defined on the architecture. [akpm@linux-foundation.org: use consistent code layout] Signed-off-by: Toshi Kani Cc: "H. Peter Anvin" Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Arnd Bergmann Cc: Dave Hansen Cc: Robert Elliott Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-generic/pgtable.h | 10 ++++++++++ mm/vmalloc.c | 4 ++++ 2 files changed, 14 insertions(+) diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index 9fb7dc7ca7f4..39f1d6a2b04d 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -700,6 +700,8 @@ static inline int pmd_protnone(pmd_t pmd) #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot); int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot); +int pud_clear_huge(pud_t *pud); +int pmd_clear_huge(pmd_t *pmd); #else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */ static inline int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot) { @@ -709,6 +711,14 @@ static inline int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot) { return 0; } +static inline int pud_clear_huge(pud_t *pud) +{ + return 0; +} +static inline int pmd_clear_huge(pmd_t *pmd) +{ + return 0; +} #endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */ #endif /* !__ASSEMBLY__ */ diff --git a/mm/vmalloc.c b/mm/vmalloc.c index a48cd061f16f..a5bbdd3b5d67 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -75,6 +75,8 @@ static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end) pmd = pmd_offset(pud, addr); do { next = pmd_addr_end(addr, end); + if (pmd_clear_huge(pmd)) + continue; if (pmd_none_or_clear_bad(pmd)) continue; vunmap_pte_range(pmd, addr, next); @@ -89,6 +91,8 @@ static void vunmap_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end) pud = pud_offset(pgd, addr); do { next = pud_addr_end(addr, end); + if (pud_clear_huge(pud)) + continue; if (pud_none_or_clear_bad(pud)) continue; vunmap_pmd_range(pud, addr, next); -- GitLab