powerpc: Rename slb0_limit() to safe_stack_limit() and add Book3E support
slb0_limit() wasn't a very descriptive name. This changes it along with
a comment explaining what it's used for, and provides a 64-bit BookE
implementation.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/mmu-book3e.h b/arch/powerpc/include/asm/mmu-book3e.h
index ec61e7b..3ea0f9a 100644
--- a/arch/powerpc/include/asm/mmu-book3e.h
+++ b/arch/powerpc/include/asm/mmu-book3e.h
@@ -245,6 +245,10 @@
extern int mmu_linear_psize;
extern int mmu_vmemmap_psize;
+#ifdef CONFIG_PPC64
+extern unsigned long linear_map_top;
+#endif
+
#endif /* !__ASSEMBLY__ */
#endif /* _ASM_POWERPC_MMU_BOOK3E_H_ */