From 85958b465c2e0de315575b1d3d7e7c2ce7126880 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Mon, 17 Mar 2008 16:37:14 -0700 Subject: x86: unify pgd ctor/dtor All pagetables need fundamentally the same setup and destruction, so just use the same code for everything. Signed-off-by: Jeremy Fitzhardinge Cc: Andi Kleen Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/mm/pgtable.c | 59 ++++++++++++--------------------------------------- 1 file changed, 13 insertions(+), 46 deletions(-) (limited to 'arch/x86/mm/pgtable.c') diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index e2ac320e615..50159764f69 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -59,50 +59,6 @@ static inline void pgd_list_del(pgd_t *pgd) list_del(&page->lru); } -#ifdef CONFIG_X86_64 -pgd_t *pgd_alloc(struct mm_struct *mm) -{ - unsigned boundary; - pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT); - unsigned long flags; - if (!pgd) - return NULL; - spin_lock_irqsave(&pgd_lock, flags); - pgd_list_add(pgd); - spin_unlock_irqrestore(&pgd_lock, flags); - /* - * Copy kernel pointers in from init. - * Could keep a freelist or slab cache of those because the kernel - * part never changes. - */ - boundary = pgd_index(__PAGE_OFFSET); - memset(pgd, 0, boundary * sizeof(pgd_t)); - memcpy(pgd + boundary, - init_level4_pgt + boundary, - (PTRS_PER_PGD - boundary) * sizeof(pgd_t)); - return pgd; -} - -void pgd_free(struct mm_struct *mm, pgd_t *pgd) -{ - unsigned long flags; - BUG_ON((unsigned long)pgd & (PAGE_SIZE-1)); - spin_lock_irqsave(&pgd_lock, flags); - pgd_list_del(pgd); - spin_unlock_irqrestore(&pgd_lock, flags); - free_page((unsigned long)pgd); -} -#else -/* - * List of all pgd's needed for non-PAE so it can invalidate entries - * in both cached and uncached pgd's; not needed for PAE since the - * kernel pmd is shared. If PAE were not to share the pmd a similar - * tactic would be needed. This is essentially codepath-based locking - * against pageattr.c; it is the unique case in which a valid change - * of kernel pagetables can't be lazily synchronized by vmalloc faults. - * vmalloc faults work because attached pagetables are never freed. - * -- wli - */ #define UNSHARED_PTRS_PER_PGD \ (SHARED_KERNEL_PMD ? KERNEL_PGD_BOUNDARY : PTRS_PER_PGD) @@ -120,7 +76,8 @@ static void pgd_ctor(void *p) ptes in non-PAE, or shared PMD in PAE), then just copy the references from swapper_pg_dir. */ if (PAGETABLE_LEVELS == 2 || - (PAGETABLE_LEVELS == 3 && SHARED_KERNEL_PMD)) { + (PAGETABLE_LEVELS == 3 && SHARED_KERNEL_PMD) || + PAGETABLE_LEVELS == 4) { clone_pgd_range(pgd + KERNEL_PGD_BOUNDARY, swapper_pg_dir + KERNEL_PGD_BOUNDARY, KERNEL_PGD_PTRS); @@ -149,6 +106,17 @@ static void pgd_dtor(void *pgd) spin_unlock_irqrestore(&pgd_lock, flags); } +/* + * List of all pgd's needed for non-PAE so it can invalidate entries + * in both cached and uncached pgd's; not needed for PAE since the + * kernel pmd is shared. If PAE were not to share the pmd a similar + * tactic would be needed. This is essentially codepath-based locking + * against pageattr.c; it is the unique case in which a valid change + * of kernel pagetables can't be lazily synchronized by vmalloc faults. + * vmalloc faults work because attached pagetables are never freed. + * -- wli + */ + #ifdef CONFIG_X86_PAE /* * Mop up any pmd pages which may still be attached to the pgd. @@ -264,7 +232,6 @@ void pgd_free(struct mm_struct *mm, pgd_t *pgd) pgd_dtor(pgd); free_page((unsigned long)pgd); } -#endif int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address, pte_t *ptep, -- cgit v1.2.3