powerpc/spufs: Use correct return value for spu_handle_mm_fault

Currently, spu_handle_mm_fault disregards the 'ret' variable and always
returns -EFAULT on error.

This change refactos spu_handle_mm_fault a little, to return the
ret variable as appropriate. This allows us to combine the error and
sucess paths.

Also, remove the #if-0-ed IS_VALID_EA() check, it has never been
used.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

diff --git a/arch/powerpc/platforms/cell/spu_fault.c b/arch/powerpc/platforms/cell/spu_fault.c
index c8b1cd4..95d8dad 100644 (file)
--- a/arch/powerpc/platforms/cell/spu_fault.c
+++ b/arch/powerpc/platforms/cell/spu_fault.c
@@ -39,60 +39,56 @@ int spu_handle_mm_fault(struct mm_struct *mm, unsigned long ea,
        unsigned long is_write;
        int ret;
 
-#if 0
-       if (!IS_VALID_EA(ea)) {
+       if (mm == NULL)
                return -EFAULT;
-       }
-#endif /* XXX */
-       if (mm == NULL) {
-               return -EFAULT;
-       }
-       if (mm->pgd == NULL) {
+
+       if (mm->pgd == NULL)
                return -EFAULT;
-       }
 
        down_read(&mm->mmap_sem);
+       ret = -EFAULT;
        vma = find_vma(mm, ea);
        if (!vma)
-               goto bad_area;
-       if (vma->vm_start <= ea)
-               goto good_area;
-       if (!(vma->vm_flags & VM_GROWSDOWN))
-               goto bad_area;
-       if (expand_stack(vma, ea))
-               goto bad_area;
-good_area:
+               goto out_unlock;
+
+       if (ea < vma->vm_start) {
+               if (!(vma->vm_flags & VM_GROWSDOWN))
+                       goto out_unlock;
+               if (expand_stack(vma, ea))
+                       goto out_unlock;
+       }
+
        is_write = dsisr & MFC_DSISR_ACCESS_PUT;
        if (is_write) {
                if (!(vma->vm_flags & VM_WRITE))
-                       goto bad_area;
+                       goto out_unlock;
        } else {
                if (dsisr & MFC_DSISR_ACCESS_DENIED)
-                       goto bad_area;
+                       goto out_unlock;
                if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
-                       goto bad_area;
+                       goto out_unlock;
        }
+
        ret = 0;
        *flt = handle_mm_fault(mm, vma, ea, is_write);
        if (unlikely(*flt & VM_FAULT_ERROR)) {
                if (*flt & VM_FAULT_OOM) {
                        ret = -ENOMEM;
-                       goto bad_area;
+                       goto out_unlock;
                } else if (*flt & VM_FAULT_SIGBUS) {
                        ret = -EFAULT;
-                       goto bad_area;
+                       goto out_unlock;
                }
                BUG();
        }
+
        if (*flt & VM_FAULT_MAJOR)
                current->maj_flt++;
        else
                current->min_flt++;
-       up_read(&mm->mmap_sem);
-       return ret;
 
-bad_area:
+out_unlock:
        up_read(&mm->mmap_sem);
-       return -EFAULT;
+       return ret;
 }
 EXPORT_SYMBOL_GPL(spu_handle_mm_fault);