1 files changed, 32 insertions, 37 deletions

diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c
index 304375a7357..a73d2d70097 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();
 }