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 <jeremy.fitzhardinge@citrix.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index e2ac320..5015976 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -59,50 +59,6 @@
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 @@
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 @@
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 @@
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,