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Diffstat (limited to 'arch/powerpc/include/asm/thread_info.h')
-rw-r--r--arch/powerpc/include/asm/thread_info.h40
1 files changed, 40 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h
index af58f1ed3952..bf5dde1a4114 100644
--- a/arch/powerpc/include/asm/thread_info.h
+++ b/arch/powerpc/include/asm/thread_info.h
@@ -45,6 +45,7 @@
#include <linux/cache.h>
#include <asm/processor.h>
#include <asm/accounting.h>
+#include <asm/ppc_asm.h>
#define SLB_PRELOAD_NR 16U
/*
@@ -175,9 +176,11 @@ static inline bool test_thread_local_flags(unsigned int flags)
#ifdef CONFIG_COMPAT
#define is_32bit_task() (test_thread_flag(TIF_32BIT))
#define is_tsk_32bit_task(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT))
+#define clear_tsk_compat_task(tsk) (clear_tsk_thread_flag(p, TIF_32BIT))
#else
#define is_32bit_task() (IS_ENABLED(CONFIG_PPC32))
#define is_tsk_32bit_task(tsk) (IS_ENABLED(CONFIG_PPC32))
+#define clear_tsk_compat_task(tsk) do { } while (0)
#endif
#if defined(CONFIG_PPC64)
@@ -186,6 +189,43 @@ static inline bool test_thread_local_flags(unsigned int flags)
#define is_elf2_task() (0)
#endif
+/*
+ * Walks up the stack frames to make sure that the specified object is
+ * entirely contained by a single stack frame.
+ *
+ * Returns:
+ * GOOD_FRAME if within a frame
+ * BAD_STACK if placed across a frame boundary (or outside stack)
+ */
+static inline int arch_within_stack_frames(const void * const stack,
+ const void * const stackend,
+ const void *obj, unsigned long len)
+{
+ const void *params;
+ const void *frame;
+
+ params = *(const void * const *)current_stack_pointer + STACK_FRAME_PARAMS;
+ frame = **(const void * const * const *)current_stack_pointer;
+
+ /*
+ * low -----------------------------------------------------------> high
+ * [backchain][metadata][params][local vars][saved registers][backchain]
+ * ^------------------------------------^
+ * | allows copies only in this region |
+ * | |
+ * params frame
+ * The metadata region contains the saved LR, CR etc.
+ */
+ while (stack <= frame && frame < stackend) {
+ if (obj + len <= frame)
+ return obj >= params ? GOOD_FRAME : BAD_STACK;
+ params = frame + STACK_FRAME_PARAMS;
+ frame = *(const void * const *)frame;
+ }
+
+ return BAD_STACK;
+}
+
#endif /* !__ASSEMBLY__ */
#endif /* __KERNEL__ */