ARM: Provide definitions and helpers for decoding the FSR register

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 15 insertions, 3 deletions

diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index cc8829d7e116..1bb38712c86b 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -25,6 +25,18 @@
 
 #include "fault.h"
 
+/*
+ * Fault status register encodings
+ */
+#define FSR_WRITE               (1 << 11)
+#define FSR_FS4                 (1 << 10)
+#define FSR_FS3_0               (15)
+
+static inline int fsr_fs(unsigned int fsr)
+{
+        return (fsr & FSR_FS3_0) | (fsr & FSR_FS4) >> 6;
+}
+
 #ifdef CONFIG_MMU
 
 #ifdef CONFIG_KPROBES
@@ -201,7 +213,7 @@ __do_page_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr,
          * memory access, so we can handle it.
          */
 good_area:
-        if (fsr & (1 << 11)) /* write? */
+        if (fsr & FSR_WRITE)
                 mask = VM_WRITE;
         else
                 mask = VM_READ|VM_EXEC|VM_WRITE;
@@ -216,7 +228,7 @@ good_area:
          * than endlessly redo the fault.
          */
 survive:
-        fault = handle_mm_fault(mm, vma, addr & PAGE_MASK, (fsr & (1 << 11)) ? FAULT_FLAG_WRITE : 0);
+        fault = handle_mm_fault(mm, vma, addr & PAGE_MASK, (fsr & FSR_WRITE) ? FAULT_FLAG_WRITE : 0);
         if (unlikely(fault & VM_FAULT_ERROR)) {
                 if (fault & VM_FAULT_OOM)
                         goto out_of_memory;
@@ -489,7 +501,7 @@ hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int, struct pt_regs *)
 asmlinkage void __exception
 do_DataAbort(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 {
-        const struct fsr_info *inf = fsr_info + (fsr & 15) + ((fsr & (1 << 10)) >> 6);
+        const struct fsr_info *inf = fsr_info + fsr_fs(fsr);
         struct siginfo info;
 
         if (!inf->fn(addr, fsr, regs))