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>

1 files changed, 22 insertions, 26 deletions

diff --git a/arch/powerpc/platforms/cell/spu_fault.c b/arch/powerpc/platforms/cell/spu_fault.c
index c8b1cd42905..95d8dadf2d8 100644
--- 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);