fedora core 6 1.2949 + vserver 2.2.0

[linux-2.6.git] / arch / powerpc / mm / slb.c

diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c
index de0c884..224e960 100644 (file)
--- a/arch/powerpc/mm/slb.c
+++ b/arch/powerpc/mm/slb.c
@@ -22,6 +22,9 @@
 #include <asm/paca.h>
 #include <asm/cputable.h>
 #include <asm/cacheflush.h>
+#include <asm/smp.h>
+#include <asm/firmware.h>
+#include <linux/compiler.h>
 
 #ifdef DEBUG
 #define DBG(fmt...) udbg_printf(fmt)
@@ -50,9 +53,32 @@ 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 create_slbe(unsigned long ea, unsigned long flags,
-                              unsigned long entry)
+static inline void slb_shadow_update(unsigned long esid, unsigned long vsid,
+                                    unsigned long entry)
 {
+       /*
+        * Clear the ESID first so the entry is not valid while we are
+        * 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;
+
+}
+
+static inline void create_shadowed_slbe(unsigned long ea, unsigned long flags,
+                                       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))
@@ -77,6 +103,10 @@ void slb_flush_and_rebolt(void)
        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);
+
        /* We need to do this all in asm, so we're sure we don't touch
         * the stack between the slbia and rebolting it. */
        asm volatile("isync\n"
@@ -164,6 +194,7 @@ static inline void patch_slb_encoding(unsigned int *insn_addr,
 void slb_initialize(void)
 {
        unsigned long linear_llp, vmalloc_llp, io_llp;
+       unsigned long lflags, vflags;
        static int slb_encoding_inited;
        extern unsigned int *slb_miss_kernel_load_linear;
        extern unsigned int *slb_miss_kernel_load_io;
@@ -196,11 +227,12 @@ void slb_initialize(void)
 #endif
        }
 
+       get_paca()->stab_rr = SLB_NUM_BOLTED;
+
        /* On iSeries the bolted entries have already been set up by
         * the hypervisor from the lparMap data in head.S */
-#ifndef CONFIG_PPC_ISERIES
- {
-       unsigned long lflags, vflags;
+       if (firmware_has_feature(FW_FEATURE_ISERIES))
+               return;
 
        lflags = SLB_VSID_KERNEL | linear_llp;
        vflags = SLB_VSID_KERNEL | vmalloc_llp;
@@ -209,17 +241,13 @@ void slb_initialize(void)
        asm volatile("isync":::"memory");
        asm volatile("slbmte  %0,%0"::"r" (0) : "memory");
        asm volatile("isync; slbia; isync":::"memory");
-       create_slbe(PAGE_OFFSET, lflags, 0);
+       create_shadowed_slbe(PAGE_OFFSET, lflags, 0);
 
-       create_slbe(VMALLOC_START, vflags, 1);
+       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");
- }
-#endif /* CONFIG_PPC_ISERIES */
-
-       get_paca()->stab_rr = SLB_NUM_BOLTED;
 }