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diff -pruN ../pristine-linux-2.6.16.13/arch/i386/mm/pageattr.c ./arch/i386/mm/pageattr.c
--- ../pristine-linux-2.6.16.13/arch/i386/mm/pageattr.c 2006-05-02 22:38:44.000000000 +0100
+++ ./arch/i386/mm/pageattr.c 2006-05-04 17:41:40.000000000 +0100
@@ -78,7 +78,7 @@ static void set_pmd_pte(pte_t *kpte, uns
unsigned long flags;
set_pte_atomic(kpte, pte); /* change init_mm */
- if (PTRS_PER_PMD > 1)
+ if (HAVE_SHARED_KERNEL_PMD)
return;
spin_lock_irqsave(&pgd_lock, flags);
diff -pruN ../pristine-linux-2.6.16.13/arch/i386/mm/pgtable.c ./arch/i386/mm/pgtable.c
--- ../pristine-linux-2.6.16.13/arch/i386/mm/pgtable.c 2006-05-02 22:38:44.000000000 +0100
+++ ./arch/i386/mm/pgtable.c 2006-05-04 17:41:40.000000000 +0100
@@ -215,9 +215,10 @@ void pgd_ctor(void *pgd, kmem_cache_t *c
spin_lock_irqsave(&pgd_lock, flags);
}
- 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 || HAVE_SHARED_KERNEL_PMD)
+ 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;
@@ -249,6 +250,30 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
goto out_oom;
set_pgd(&pgd[i], __pgd(1 + __pa(pmd)));
}
+
+ if (!HAVE_SHARED_KERNEL_PMD) {
+ unsigned long flags;
+
+ for (i = USER_PTRS_PER_PGD; i < PTRS_PER_PGD; i++) {
+ pmd_t *pmd = kmem_cache_alloc(pmd_cache, GFP_KERNEL);
+ if (!pmd)
+ goto out_oom;
+ set_pgd(&pgd[USER_PTRS_PER_PGD], __pgd(1 + __pa(pmd)));
+ }
+
+ spin_lock_irqsave(&pgd_lock, flags);
+ for (i = USER_PTRS_PER_PGD; i < PTRS_PER_PGD; i++) {
+ unsigned long v = (unsigned long)i << PGDIR_SHIFT;
+ pgd_t *kpgd = pgd_offset_k(v);
+ pud_t *kpud = pud_offset(kpgd, v);
+ pmd_t *kpmd = pmd_offset(kpud, v);
+ pmd_t *pmd = (void *)__va(pgd_val(pgd[i])-1);
+ memcpy(pmd, kpmd, PAGE_SIZE);
+ }
+ pgd_list_add(pgd);
+ spin_unlock_irqrestore(&pgd_lock, flags);
+ }
+
return pgd;
out_oom:
@@ -263,9 +288,23 @@ void pgd_free(pgd_t *pgd)
int i;
/* 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)
- kmem_cache_free(pmd_cache, (void *)__va(pgd_val(pgd[i])-1));
+ if (PTRS_PER_PMD > 1) {
+ for (i = 0; i < USER_PTRS_PER_PGD; ++i) {
+ pmd_t *pmd = (void *)__va(pgd_val(pgd[i])-1);
+ kmem_cache_free(pmd_cache, pmd);
+ }
+ if (!HAVE_SHARED_KERNEL_PMD) {
+ unsigned long flags;
+ spin_lock_irqsave(&pgd_lock, flags);
+ pgd_list_del(pgd);
+ spin_unlock_irqrestore(&pgd_lock, flags);
+ for (i = USER_PTRS_PER_PGD; i < PTRS_PER_PGD; i++) {
+ pmd_t *pmd = (void *)__va(pgd_val(pgd[i])-1);
+ memset(pmd, 0, PTRS_PER_PMD*sizeof(pmd_t));
+ kmem_cache_free(pmd_cache, pmd);
+ }
+ }
+ }
/* in the non-PAE case, free_pgtables() clears user pgd entries */
kmem_cache_free(pgd_cache, pgd);
}
diff -pruN ../pristine-linux-2.6.16.13/include/asm-i386/pgtable-2level-defs.h ./include/asm-i386/pgtable-2level-defs.h
--- ../pristine-linux-2.6.16.13/include/asm-i386/pgtable-2level-defs.h 2006-05-02 22:38:44.000000000 +0100
+++ ./include/asm-i386/pgtable-2level-defs.h 2006-05-04 17:41:40.000000000 +0100
@@ -1,6 +1,8 @@
#ifndef _I386_PGTABLE_2LEVEL_DEFS_H
#define _I386_PGTABLE_2LEVEL_DEFS_H
+#define HAVE_SHARED_KERNEL_PMD 0
+
/*
* traditional i386 two-level paging structure:
*/
diff -pruN ../pristine-linux-2.6.16.13/include/asm-i386/pgtable-3level-defs.h ./include/asm-i386/pgtable-3level-defs.h
--- ../pristine-linux-2.6.16.13/include/asm-i386/pgtable-3level-defs.h 2006-05-02 22:38:44.000000000 +0100
+++ ./include/asm-i386/pgtable-3level-defs.h 2006-05-04 17:41:40.000000000 +0100
@@ -1,6 +1,8 @@
#ifndef _I386_PGTABLE_3LEVEL_DEFS_H
#define _I386_PGTABLE_3LEVEL_DEFS_H
+#define HAVE_SHARED_KERNEL_PMD 1
+
/*
* PGDIR_SHIFT determines what a top-level page table entry can map
*/
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