1 files changed, 32 insertions, 37 deletions

diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c
index 304375a73574..a73d2d700973 100644
--- a/arch/powerpc/mm/slb.c
+++ b/arch/powerpc/mm/slb.c
@@ -53,7 +53,8 @@ static inline unsigned long mk_vsid_data(unsigned long ea, unsigned long flags)
         return (get_kernel_vsid(ea) << SLB_VSID_SHIFT) | flags;
 }
 
-static inline void slb_shadow_update(unsigned long esid, unsigned long vsid,
+static inline void slb_shadow_update(unsigned long ea,
+                                     unsigned long flags,
                                      unsigned long entry)
 {
         /*
@@ -61,28 +62,16 @@ static inline void slb_shadow_update(unsigned long esid, unsigned long vsid,
          * updating it.
          */
         get_slb_shadow()->save_area[entry].esid = 0;
-        barrier();
-        get_slb_shadow()->save_area[entry].vsid = vsid;
-        barrier();
-        get_slb_shadow()->save_area[entry].esid = esid;
-
+        smp_wmb();
+        get_slb_shadow()->save_area[entry].vsid = mk_vsid_data(ea, flags);
+        smp_wmb();
+        get_slb_shadow()->save_area[entry].esid = mk_esid_data(ea, entry);
+        smp_wmb();
 }
 
-static inline void create_shadowed_slbe(unsigned long ea, unsigned long flags,
-                                        unsigned long entry)
+static inline void slb_shadow_clear(unsigned long entry)
 {
-        /*
-         * Updating the shadow buffer before writing the SLB ensures
-         * we don't get a stale entry here if we get preempted by PHYP
-         * between these two statements.
-         */
-        slb_shadow_update(mk_esid_data(ea, entry), mk_vsid_data(ea, flags),
-                          entry);
-
-        asm volatile("slbmte  %0,%1" :
-                     : "r" (mk_vsid_data(ea, flags)),
-                       "r" (mk_esid_data(ea, entry))
-                     : "memory" );
+        get_slb_shadow()->save_area[entry].esid = 0;
 }
 
 void slb_flush_and_rebolt(void)
@@ -100,12 +89,13 @@ void slb_flush_and_rebolt(void)
         vflags = SLB_VSID_KERNEL | vmalloc_llp;
 
         ksp_esid_data = mk_esid_data(get_paca()->kstack, 2);
-        if ((ksp_esid_data & ESID_MASK) == PAGE_OFFSET)
+        if ((ksp_esid_data & ESID_MASK) == PAGE_OFFSET) {
                 ksp_esid_data &= ~SLB_ESID_V;
-
-        /* Only third entry (stack) may change here so only resave that */
-        slb_shadow_update(ksp_esid_data,
-                          mk_vsid_data(ksp_esid_data, lflags), 2);
+                slb_shadow_clear(2);
+        } else {
+                /* Update stack entry; others don't change */
+                slb_shadow_update(get_paca()->kstack, lflags, 2);
+        }
 
         /* We need to do this all in asm, so we're sure we don't touch
          * the stack between the slbia and rebolting it. */
@@ -123,6 +113,15 @@ void slb_flush_and_rebolt(void)
                      : "memory");
 }
 
+void slb_vmalloc_update(void)
+{
+        unsigned long vflags;
+
+        vflags = SLB_VSID_KERNEL | mmu_psize_defs[mmu_vmalloc_psize].sllp;
+        slb_shadow_update(VMALLOC_START, vflags, 1);
+        slb_flush_and_rebolt();
+}
+
 /* Flush all user entries from the segment table of the current processor. */
 void switch_slb(struct task_struct *tsk, struct mm_struct *mm)
 {
@@ -227,16 +226,12 @@ void slb_initialize(void)
         vflags = SLB_VSID_KERNEL | vmalloc_llp;
 
         /* Invalidate the entire SLB (even slot 0) & all the ERATS */
-        asm volatile("isync":::"memory");
-        asm volatile("slbmte  %0,%0"::"r" (0) : "memory");
-        asm volatile("isync; slbia; isync":::"memory");
-        create_shadowed_slbe(PAGE_OFFSET, lflags, 0);
-
-        create_shadowed_slbe(VMALLOC_START, vflags, 1);
-
-        /* We don't bolt the stack for the time being - we're in boot,
-         * so the stack is in the bolted segment.  By the time it goes
-         * elsewhere, we'll call _switch() which will bolt in the new
-         * one. */
-        asm volatile("isync":::"memory");
+        slb_shadow_update(PAGE_OFFSET, lflags, 0);
+        asm volatile("isync; slbia; sync; slbmte  %0,%1; isync" ::
+                     "r" (get_slb_shadow()->save_area[0].vsid),
+                     "r" (get_slb_shadow()->save_area[0].esid) : "memory");
+
+        slb_shadow_update(VMALLOC_START, vflags, 1);
+
+        slb_flush_and_rebolt();
 }