sgi-gru: restructure the GRU vtop functions

Restructure the GRU vtop functions in preparation for future changes.
This patch simply moves code around & does not change the algorithm.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/misc/sgi-gru/grufault.c b/drivers/misc/sgi-gru/grufault.c
index 8ae426e..bf6e9f7 100644 (file)
--- a/drivers/misc/sgi-gru/grufault.c
+++ b/drivers/misc/sgi-gru/grufault.c
@@ -267,6 +267,44 @@ err:
        return 1;
 }
 
+static int gru_vtop(struct gru_thread_state *gts, unsigned long vaddr,
+                   int write, int atomic, unsigned long *gpa, int *pageshift)
+{
+       struct mm_struct *mm = gts->ts_mm;
+       struct vm_area_struct *vma;
+       unsigned long paddr;
+       int ret, ps;
+
+       vma = find_vma(mm, vaddr);
+       if (!vma)
+               goto inval;
+
+       /*
+        * Atomic lookup is faster & usually works even if called in non-atomic
+        * context.
+        */
+       rmb();  /* Must/check ms_range_active before loading PTEs */
+       ret = atomic_pte_lookup(vma, vaddr, write, &paddr, &ps);
+       if (ret) {
+               if (atomic)
+                       goto upm;
+               if (non_atomic_pte_lookup(vma, vaddr, write, &paddr, &ps))
+                       goto inval;
+       }
+       if (is_gru_paddr(paddr))
+               goto inval;
+       paddr = paddr & ~((1UL << ps) - 1);
+       *gpa = uv_soc_phys_ram_to_gpa(paddr);
+       *pageshift = ps;
+       return 0;
+
+inval:
+       return -1;
+upm:
+       return -2;
+}
+
+
 /*
  * Drop a TLB entry into the GRU. The fault is described by info in an TFH.
  *     Input:
@@ -281,10 +319,8 @@ static int gru_try_dropin(struct gru_thread_state *gts,
                          struct gru_tlb_fault_handle *tfh,
                          unsigned long __user *cb)
 {
-       struct mm_struct *mm = gts->ts_mm;
-       struct vm_area_struct *vma;
-       int pageshift, asid, write, ret;
-       unsigned long paddr, gpa, vaddr;
+       int pageshift = 0, asid, write, ret, atomic = !cb;
+       unsigned long gpa = 0, vaddr = 0;
 
        /*
         * NOTE: The GRU contains magic hardware that eliminates races between
@@ -318,28 +354,12 @@ static int gru_try_dropin(struct gru_thread_state *gts,
        if (atomic_read(&gts->ts_gms->ms_range_active))
                goto failactive;
 
-       vma = find_vma(mm, vaddr);
-       if (!vma)
-               goto failinval;
-
-       /*
-        * Atomic lookup is faster & usually works even if called in non-atomic
-        * context.
-        */
-       rmb();  /* Must/check ms_range_active before loading PTEs */
-       ret = atomic_pte_lookup(vma, vaddr, write, &paddr, &pageshift);
-       if (ret) {
-               if (!cb)
-                       goto failupm;
-               if (non_atomic_pte_lookup(vma, vaddr, write, &paddr,
-                                         &pageshift))
-                       goto failinval;
-       }
-       if (is_gru_paddr(paddr))
+       ret = gru_vtop(gts, vaddr, write, atomic, &gpa, &pageshift);
+       if (ret == -1)
                goto failinval;
+       if (ret == -2)
+               goto failupm;
 
-       paddr = paddr & ~((1UL << pageshift) - 1);
-       gpa = uv_soc_phys_ram_to_gpa(paddr);
        gru_cb_set_istatus_active(cb);
        tfh_write_restart(tfh, gpa, GAA_RAM, vaddr, asid, write,
                          GRU_PAGESIZE(pageshift));