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-rw-r--r--arch/s390/include/asm/pgtable.h1
-rw-r--r--arch/s390/mm/fault.c21
-rw-r--r--arch/s390/mm/init.c1
3 files changed, 20 insertions, 3 deletions
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 785229ae39cb..85cd4b039de6 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -38,6 +38,7 @@
extern pgd_t swapper_pg_dir[] __attribute__ ((aligned (4096)));
extern void paging_init(void);
extern void vmem_map_init(void);
+extern void fault_init(void);
/*
* The S390 doesn't have any external MMU info: the kernel page
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 2505b2ea0ef1..b49d12073f10 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -52,6 +52,19 @@
#define VM_FAULT_BADMAP 0x020000
#define VM_FAULT_BADACCESS 0x040000
+static unsigned long store_indication;
+
+void fault_init(void)
+{
+ unsigned long long facility_list[2];
+
+ if (stfle(facility_list, 2) < 2)
+ return;
+ if ((facility_list[0] & (1ULL << 61)) &&
+ (facility_list[1] & (1ULL << 52)))
+ store_indication = 0xc00;
+}
+
static inline int notify_page_fault(struct pt_regs *regs)
{
int ret = 0;
@@ -294,7 +307,7 @@ static inline int do_exception(struct pt_regs *regs, int access,
struct mm_struct *mm;
struct vm_area_struct *vma;
unsigned long address;
- int fault;
+ int fault, write;
if (notify_page_fault(regs))
return 0;
@@ -348,8 +361,10 @@ static inline int do_exception(struct pt_regs *regs, int access,
* make sure we exit gracefully rather than endlessly redo
* the fault.
*/
- fault = handle_mm_fault(mm, vma, address,
- (access == VM_WRITE) ? FAULT_FLAG_WRITE : 0);
+ write = (access == VM_WRITE ||
+ (trans_exc_code & store_indication) == 0x400) ?
+ FAULT_FLAG_WRITE : 0;
+ fault = handle_mm_fault(mm, vma, address, write);
if (unlikely(fault & VM_FAULT_ERROR))
goto out_up;
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 852a3fec1ece..bb409332a484 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -124,6 +124,7 @@ void __init paging_init(void)
#endif
max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
free_area_init_nodes(max_zone_pfns);
+ fault_init();
}
void __init mem_init(void)
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