X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=include%2Fasm-s390%2Fmmu_context.h;h=4c2fbf48c9c43fe2fa0a7384bc55c576d6dfc23c;hb=a7c2a10dab4e5122cbcfa3d5e9d589a52ccc2287;hp=05b842126b993295d95912c8f057f5cb182c5397;hpb=46015977e70f672ae6b20a1b5fb1e361208365ba;p=linux-2.6

diff --git a/include/asm-s390/mmu_context.h b/include/asm-s390/mmu_context.h
index 05b842126b..4c2fbf48c9 100644
--- a/include/asm-s390/mmu_context.h
+++ b/include/asm-s390/mmu_context.h
@@ -10,12 +10,27 @@
 #define __S390_MMU_CONTEXT_H
 
 #include <asm/pgalloc.h>
+#include <asm/uaccess.h>
 #include <asm-generic/mm_hooks.h>
 
-/*
- * get a new mmu context.. S390 don't know about contexts.
- */
-#define init_new_context(tsk,mm)        0
+static inline int init_new_context(struct task_struct *tsk,
+				   struct mm_struct *mm)
+{
+	mm->context.asce_bits = _ASCE_TABLE_LENGTH | _ASCE_USER_BITS;
+#ifdef CONFIG_64BIT
+	mm->context.asce_bits |= _ASCE_TYPE_REGION3;
+#endif
+	if (current->mm->context.pgstes) {
+		mm->context.noexec = 0;
+		mm->context.pgstes = 1;
+	} else {
+		mm->context.noexec = s390_noexec;
+		mm->context.pgstes = 0;
+	}
+	mm->context.asce_limit = STACK_TOP_MAX;
+	crst_table_init((unsigned long *) mm->pgd, pgd_entry_type(mm));
+	return 0;
+}
 
 #define destroy_context(mm)             do { } while (0)
 
@@ -28,31 +43,24 @@
 static inline void update_mm(struct mm_struct *mm, struct task_struct *tsk)
 {
 	pgd_t *pgd = mm->pgd;
-	unsigned long asce_bits;
 
-	/* Calculate asce bits from the first pgd table entry. */
-	asce_bits = _ASCE_TABLE_LENGTH | _ASCE_USER_BITS;
-#ifdef CONFIG_64BIT
-	asce_bits |= _ASCE_TYPE_REGION3;
-#endif
-	S390_lowcore.user_asce = asce_bits | __pa(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(pgd) ? : pgd;
-		S390_lowcore.user_exec_asce = asce_bits | __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);
 }
@@ -64,7 +72,6 @@ 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 */