[ARM] 5387/1: Add ptrace VFP support on ARM

This patch adds ptrace support for setting and getting the VFP registers
using PTRACE_SETVFPREGS and PTRACE_GETVFPREGS. The user_vfp structure
defined in asm/user.h contains 32 double registers (to cover VFPv3 and
Neon hardware) and the FPSCR register.

Cc: Paul Brook <paul@codesourcery.com>
Cc: Daniel Jacobowitz <dan@codesourcery.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

3 files changed, 13 insertions, 0 deletions

diff --git a/arch/arm/include/asm/ptrace.h b/arch/arm/include/asm/ptrace.h
index 73192618f1c2..236a06b9b7ce 100644
--- a/arch/arm/include/asm/ptrace.h
+++ b/arch/arm/include/asm/ptrace.h
@@ -27,6 +27,8 @@
 /* PTRACE_SYSCALL is 24 */
 #define PTRACE_GETCRUNCHREGS    25
 #define PTRACE_SETCRUNCHREGS    26
+#define PTRACE_GETVFPREGS       27
+#define PTRACE_SETVFPREGS       28
 
 /*
  * PSR bits
diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h
index 68b9ec82a37f..b9dc8a842573 100644
--- a/arch/arm/include/asm/thread_info.h
+++ b/arch/arm/include/asm/thread_info.h
@@ -113,6 +113,8 @@ extern void iwmmxt_task_restore(struct thread_info *, void *);
 extern void iwmmxt_task_release(struct thread_info *);
 extern void iwmmxt_task_switch(struct thread_info *);
 
+extern void vfp_sync_state(struct thread_info *thread);
+
 #endif
 
 /*
diff --git a/arch/arm/include/asm/user.h b/arch/arm/include/asm/user.h
index 825c1e7c582d..df95e050f9dd 100644
--- a/arch/arm/include/asm/user.h
+++ b/arch/arm/include/asm/user.h
@@ -81,4 +81,13 @@ struct user{
 #define HOST_TEXT_START_ADDR (u.start_code)
 #define HOST_STACK_END_ADDR (u.start_stack + u.u_ssize * NBPG)
 
+/*
+ * User specific VFP registers. If only VFPv2 is present, registers 16 to 31
+ * are ignored by the ptrace system call.
+ */
+struct user_vfp {
+        unsigned long long fpregs[32];
+        unsigned long fpscr;
+};
+
 #endif /* _ARM_USER_H */