[POWERPC] Introduce address space "slices"

[powerpc.git] / arch / powerpc / mm / mmu_context_64.c

diff --git a/arch/powerpc/mm/mmu_context_64.c b/arch/powerpc/mm/mmu_context_64.c
index 65d18dc..7a78cdc 100644 (file)
--- a/arch/powerpc/mm/mmu_context_64.c
+++ b/arch/powerpc/mm/mmu_context_64.c
@@ -10,7 +10,6 @@
  *
  */
 
-#include <linux/config.h>
 #include <linux/sched.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
@@ -29,6 +28,7 @@ int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
 {
        int index;
        int err;
+       int new_context = (mm->context.id == 0);
 
 again:
        if (!idr_pre_get(&mmu_context_idr, GFP_KERNEL))
@@ -44,14 +44,25 @@ again:
                return err;
 
        if (index > MAX_CONTEXT) {
+               spin_lock(&mmu_context_lock);
                idr_remove(&mmu_context_idr, index);
+               spin_unlock(&mmu_context_lock);
                return -ENOMEM;
        }
 
        mm->context.id = index;
+#ifdef CONFIG_PPC_MM_SLICES
+       /* The old code would re-promote on fork, we don't do that
+        * when using slices as it could cause problem promoting slices
+        * that have been forced down to 4K
+        */
+       if (new_context)
+               slice_set_user_psize(mm, mmu_virtual_psize);
+#else
        mm->context.user_psize = mmu_virtual_psize;
        mm->context.sllp = SLB_VSID_USER |
                mmu_psize_defs[mmu_virtual_psize].sllp;
+#endif
 
        return 0;
 }