[PATCH] ppc64: dynamically allocate segment tables

[cascardo/linux.git] / arch / ppc64 / mm / stab.c

diff --git a/arch/ppc64/mm/stab.c b/arch/ppc64/mm/stab.c
index df4bbe1..1b83f00 100644 (file)
--- a/arch/ppc64/mm/stab.c
+++ b/arch/ppc64/mm/stab.c
@@ -18,6 +18,8 @@
 #include <asm/mmu_context.h>
 #include <asm/paca.h>
 #include <asm/cputable.h>
+#include <asm/lmb.h>
+#include <asm/abs_addr.h>
 
 struct stab_entry {
        unsigned long esid_data;
@@ -223,6 +225,39 @@ void switch_stab(struct task_struct *tsk, struct mm_struct *mm)
 
 extern void slb_initialize(void);
 
+/*
+ * Allocate segment tables for secondary CPUs.  These must all go in
+ * the first (bolted) segment, so that do_stab_bolted won't get a
+ * recursive segment miss on the segment table itself.
+ */
+void stabs_alloc(void)
+{
+       int cpu;
+
+       if (cpu_has_feature(CPU_FTR_SLB))
+               return;
+
+       for_each_cpu(cpu) {
+               unsigned long newstab;
+
+               if (cpu == 0)
+                       continue; /* stab for CPU 0 is statically allocated */
+
+               newstab = lmb_alloc_base(PAGE_SIZE, PAGE_SIZE, 1<<SID_SHIFT);
+               if (! newstab)
+                       panic("Unable to allocate segment table for CPU %d.\n",
+                             cpu);
+
+               newstab += KERNELBASE;
+
+               memset((void *)newstab, 0, PAGE_SIZE);
+
+               paca[cpu].stab_addr = newstab;
+               paca[cpu].stab_real = virt_to_abs(newstab);
+               printk(KERN_DEBUG "Segment table for CPU %d at 0x%lx virtual, 0x%lx absolute\n", cpu, paca[cpu].stab_addr, paca[cpu].stab_real);
+       }
+}
+
 /*
  * Build an entry for the base kernel segment and put it into
  * the segment table or SLB.  All other segment table or SLB