[ARM] 3664/1: crunch: add signal frame save/restore

Patch from Lennert Buytenhek

This patch makes the kernel save Crunch state in userland signal frames,
so that any userland signal handler can safely use the Crunch coprocessor
without corrupting the Crunch state of the code it preempted.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 14 insertions, 0 deletions

diff --git a/include/asm-arm/ucontext.h b/include/asm-arm/ucontext.h
index 9e6f7ca9f5ae..bf65e9f4525d 100644
--- a/include/asm-arm/ucontext.h
+++ b/include/asm-arm/ucontext.h
@@ -35,6 +35,17 @@ struct ucontext {
  * bytes, to prevent unpredictable padding in the signal frame.
  */
 
+#ifdef CONFIG_CRUNCH
+#define CRUNCH_MAGIC            0x5065cf03
+#define CRUNCH_STORAGE_SIZE     (CRUNCH_SIZE + 8)
+
+struct crunch_sigframe {
+        unsigned long   magic;
+        unsigned long   size;
+        struct crunch_state     storage;
+} __attribute__((__aligned__(8)));
+#endif
+
 #ifdef CONFIG_IWMMXT
 /* iwmmxt_area is 0x98 bytes long, preceeded by 8 bytes of signature */
 #define IWMMXT_MAGIC            0x12ef842a
@@ -74,6 +85,9 @@ struct vfp_sigframe
  * one of these.
  */
 struct aux_sigframe {
+#ifdef CONFIG_CRUNCH
+        struct crunch_sigframe  crunch;
+#endif
 #ifdef CONFIG_IWMMXT
         struct iwmmxt_sigframe  iwmmxt;
 #endif