Merge branch 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6

* 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6:
  [S390] dynamic page tables.
  [S390] Add four level page tables for CONFIG_64BIT=y.
  [S390] 1K/2K page table pages.
  [S390] Remove a.out header file.
  [S390] sclp_vt220: Fix vt220 initialization
  [S390] qdio: avoid hang when establishing qdio queues
  [S390] VMEM_MAX_PHYS overflow on 31 bit.
  [S390] zcrypt: Do not start ap poll thread per default
  [S390] Fix __ffs_word_loop/__ffz_word_loop inlnie assembly.
  [S390] Wire up new timerfd syscalls.
  [S390] Update default configuration.

1 files changed, 12 insertions, 8 deletions

diff --git a/include/asm-s390/mmu_context.h b/include/asm-s390/mmu_context.h
index a77d4ba3c8e..b5a34c6f91a 100644
--- a/include/asm-s390/mmu_context.h
+++ b/include/asm-s390/mmu_context.h
@@ -10,15 +10,19 @@
 #define __S390_MMU_CONTEXT_H
 
 #include <asm/pgalloc.h>
+#include <asm/uaccess.h>
 #include <asm-generic/mm_hooks.h>
 
 static inline int init_new_context(struct task_struct *tsk,
 				   struct mm_struct *mm)
 {
-	mm->context = _ASCE_TABLE_LENGTH | _ASCE_USER_BITS;
+	mm->context.asce_bits = _ASCE_TABLE_LENGTH | _ASCE_USER_BITS;
 #ifdef CONFIG_64BIT
-	mm->context |= _ASCE_TYPE_REGION3;
+	mm->context.asce_bits |= _ASCE_TYPE_REGION3;
 #endif
+	mm->context.noexec = s390_noexec;
+	mm->context.asce_limit = STACK_TOP_MAX;
+	crst_table_init((unsigned long *) mm->pgd, pgd_entry_type(mm));
 	return 0;
 }
 
@@ -32,24 +36,25 @@ static inline int init_new_context(struct task_struct *tsk,
 
 static inline void update_mm(struct mm_struct *mm, struct task_struct *tsk)
 {
-	S390_lowcore.user_asce = mm->context | __pa(mm->pgd);
+	pgd_t *pgd = mm->pgd;
+
+	S390_lowcore.user_asce = mm->context.asce_bits | __pa(pgd);
 	if (switch_amode) {
 		/* Load primary space page table origin. */
-		pgd_t *shadow_pgd = get_shadow_table(mm->pgd) ? : mm->pgd;
-		S390_lowcore.user_exec_asce = mm->context | __pa(shadow_pgd);
+		pgd = mm->context.noexec ? get_shadow_table(pgd) : pgd;
+		S390_lowcore.user_exec_asce = mm->context.asce_bits | __pa(pgd);
 		asm volatile(LCTL_OPCODE" 1,1,%0\n"
 			     : : "m" (S390_lowcore.user_exec_asce) );
 	} else
 		/* Load home space page table origin. */
 		asm volatile(LCTL_OPCODE" 13,13,%0"
 			     : : "m" (S390_lowcore.user_asce) );
+	set_fs(current->thread.mm_segment);
 }
 
 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
 			     struct task_struct *tsk)
 {
-	if (unlikely(prev == next))
-		return;
 	cpu_set(smp_processor_id(), next->cpu_vm_mask);
 	update_mm(next, tsk);
 }
@@ -61,7 +66,6 @@ static inline void activate_mm(struct mm_struct *prev,
                                struct mm_struct *next)
 {
         switch_mm(prev, next, current);
-	set_fs(current->thread.mm_segment);
 }
 
 #endif /* __S390_MMU_CONTEXT_H */