#include <linux/pagemap.h>
#include <linux/spinlock.h>
#include <linux/module.h>
+#include <linux/quicklist.h>
#include <asm/system.h>
#include <asm/pgtable.h>
}
static int fixmaps;
-#ifndef CONFIG_COMPAT_VDSO
unsigned long __FIXADDR_TOP = 0xfffff000;
EXPORT_SYMBOL(__FIXADDR_TOP);
-#endif
void __set_fixmap (enum fixed_addresses idx, unsigned long phys, pgprot_t flags)
{
void reserve_top_address(unsigned long reserve)
{
BUG_ON(fixmaps > 0);
-#ifdef CONFIG_COMPAT_VDSO
- BUG_ON(reserve != 0);
-#else
+ printk(KERN_INFO "Reserving virtual address space above 0x%08x\n",
+ (int)-reserve);
__FIXADDR_TOP = -reserve - PAGE_SIZE;
__VMALLOC_RESERVE += reserve;
-#endif
}
pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
* 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.
- * The locking scheme was chosen on the basis of manfred's
- * recommendations and having no core impact whatsoever.
* -- wli
*/
DEFINE_SPINLOCK(pgd_lock);
set_page_private(next, (unsigned long)pprev);
}
-void pgd_ctor(void *pgd, struct kmem_cache *cache, unsigned long unused)
+
+
+#if (PTRS_PER_PMD == 1)
+/* Non-PAE pgd constructor */
+static void pgd_ctor(void *pgd)
{
unsigned long flags;
- if (PTRS_PER_PMD == 1) {
- memset(pgd, 0, USER_PTRS_PER_PGD*sizeof(pgd_t));
- spin_lock_irqsave(&pgd_lock, flags);
- }
+ /* !PAE, no pagetable sharing */
+ memset(pgd, 0, USER_PTRS_PER_PGD*sizeof(pgd_t));
+
+ spin_lock_irqsave(&pgd_lock, flags);
+ /* must happen under lock */
clone_pgd_range((pgd_t *)pgd + USER_PTRS_PER_PGD,
swapper_pg_dir + USER_PTRS_PER_PGD,
KERNEL_PGD_PTRS);
-
- if (PTRS_PER_PMD > 1)
- return;
-
- /* must happen under lock */
paravirt_alloc_pd_clone(__pa(pgd) >> PAGE_SHIFT,
- __pa(swapper_pg_dir) >> PAGE_SHIFT,
- USER_PTRS_PER_PGD, PTRS_PER_PGD - USER_PTRS_PER_PGD);
-
+ __pa(swapper_pg_dir) >> PAGE_SHIFT,
+ USER_PTRS_PER_PGD,
+ KERNEL_PGD_PTRS);
pgd_list_add(pgd);
spin_unlock_irqrestore(&pgd_lock, flags);
}
+#else /* PTRS_PER_PMD > 1 */
+/* PAE pgd constructor */
+static void pgd_ctor(void *pgd)
+{
+ /* PAE, kernel PMD may be shared */
+
+ if (SHARED_KERNEL_PMD) {
+ clone_pgd_range((pgd_t *)pgd + USER_PTRS_PER_PGD,
+ swapper_pg_dir + USER_PTRS_PER_PGD,
+ KERNEL_PGD_PTRS);
+ } else {
+ unsigned long flags;
+
+ memset(pgd, 0, USER_PTRS_PER_PGD*sizeof(pgd_t));
+ spin_lock_irqsave(&pgd_lock, flags);
+ pgd_list_add(pgd);
+ spin_unlock_irqrestore(&pgd_lock, flags);
+ }
+}
+#endif /* PTRS_PER_PMD */
-/* never called when PTRS_PER_PMD > 1 */
-void pgd_dtor(void *pgd, struct kmem_cache *cache, unsigned long unused)
+static void pgd_dtor(void *pgd)
{
unsigned long flags; /* can be called from interrupt context */
+ if (SHARED_KERNEL_PMD)
+ return;
+
paravirt_release_pd(__pa(pgd) >> PAGE_SHIFT);
spin_lock_irqsave(&pgd_lock, flags);
pgd_list_del(pgd);
spin_unlock_irqrestore(&pgd_lock, flags);
}
+#define UNSHARED_PTRS_PER_PGD \
+ (SHARED_KERNEL_PMD ? USER_PTRS_PER_PGD : PTRS_PER_PGD)
+
+/* If we allocate a pmd for part of the kernel address space, then
+ make sure its initialized with the appropriate kernel mappings.
+ Otherwise use a cached zeroed pmd. */
+static pmd_t *pmd_cache_alloc(int idx)
+{
+ pmd_t *pmd;
+
+ if (idx >= USER_PTRS_PER_PGD) {
+ pmd = (pmd_t *)__get_free_page(GFP_KERNEL);
+
+ if (pmd)
+ memcpy(pmd,
+ (void *)pgd_page_vaddr(swapper_pg_dir[idx]),
+ sizeof(pmd_t) * PTRS_PER_PMD);
+ } else
+ pmd = kmem_cache_alloc(pmd_cache, GFP_KERNEL);
+
+ return pmd;
+}
+
+static void pmd_cache_free(pmd_t *pmd, int idx)
+{
+ if (idx >= USER_PTRS_PER_PGD)
+ free_page((unsigned long)pmd);
+ else
+ kmem_cache_free(pmd_cache, pmd);
+}
+
pgd_t *pgd_alloc(struct mm_struct *mm)
{
int i;
- pgd_t *pgd = kmem_cache_alloc(pgd_cache, GFP_KERNEL);
+ pgd_t *pgd = quicklist_alloc(0, GFP_KERNEL, pgd_ctor);
if (PTRS_PER_PMD == 1 || !pgd)
return pgd;
- for (i = 0; i < USER_PTRS_PER_PGD; ++i) {
- pmd_t *pmd = kmem_cache_alloc(pmd_cache, GFP_KERNEL);
+ for (i = 0; i < UNSHARED_PTRS_PER_PGD; ++i) {
+ pmd_t *pmd = pmd_cache_alloc(i);
+
if (!pmd)
goto out_oom;
+
paravirt_alloc_pd(__pa(pmd) >> PAGE_SHIFT);
set_pgd(&pgd[i], __pgd(1 + __pa(pmd)));
}
pgd_t pgdent = pgd[i];
void* pmd = (void *)__va(pgd_val(pgdent)-1);
paravirt_release_pd(__pa(pmd) >> PAGE_SHIFT);
- kmem_cache_free(pmd_cache, pmd);
+ pmd_cache_free(pmd, i);
}
- kmem_cache_free(pgd_cache, pgd);
+ quicklist_free(0, pgd_dtor, pgd);
return NULL;
}
/* in the PAE case user pgd entries are overwritten before usage */
if (PTRS_PER_PMD > 1)
- for (i = 0; i < USER_PTRS_PER_PGD; ++i) {
+ for (i = 0; i < UNSHARED_PTRS_PER_PGD; ++i) {
pgd_t pgdent = pgd[i];
void* pmd = (void *)__va(pgd_val(pgdent)-1);
paravirt_release_pd(__pa(pmd) >> PAGE_SHIFT);
- kmem_cache_free(pmd_cache, pmd);
+ pmd_cache_free(pmd, i);
}
/* in the non-PAE case, free_pgtables() clears user pgd entries */
- kmem_cache_free(pgd_cache, pgd);
+ quicklist_free(0, pgd_dtor, pgd);
}
+
+void check_pgt_cache(void)
+{
+ quicklist_trim(0, pgd_dtor, 25, 16);
+}
+
projects / linux-2.6 / blobdiff