1 files changed, 25 insertions, 0 deletions

diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index 8fc69891e117..d4f7fd4550e1 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -32,6 +32,7 @@
 #include <linux/nmi.h>
 #include <linux/cpu.h>
 
+#include <asm/abi.h>
 #include <asm/asm.h>
 #include <asm/bootinfo.h>
 #include <asm/cpu.h>
@@ -39,6 +40,7 @@
 #include <asm/dsp.h>
 #include <asm/fpu.h>
 #include <asm/irq.h>
+#include <asm/mips-cps.h>
 #include <asm/msa.h>
 #include <asm/pgtable.h>
 #include <asm/mipsregs.h>
@@ -645,6 +647,29 @@ out:
         return pc;
 }
 
+unsigned long mips_stack_top(void)
+{
+        unsigned long top = TASK_SIZE & PAGE_MASK;
+
+        /* One page for branch delay slot "emulation" */
+        top -= PAGE_SIZE;
+
+        /* Space for the VDSO, data page & GIC user page */
+        top -= PAGE_ALIGN(current->thread.abi->vdso->size);
+        top -= PAGE_SIZE;
+        top -= mips_gic_present() ? PAGE_SIZE : 0;
+
+        /* Space for cache colour alignment */
+        if (cpu_has_dc_aliases)
+                top -= shm_align_mask + 1;
+
+        /* Space to randomize the VDSO base */
+        if (current->flags & PF_RANDOMIZE)
+                top -= VDSO_RANDOMIZE_SIZE;
+
+        return top;
+}
+
 /*
  * Don't forget that the stack pointer must be aligned on a 8 bytes
  * boundary for 32-bits ABI and 16 bytes for 64-bits ABI.