Merge branches 'x86/prototypes', 'x86/x2apic' and 'x86/debug' into x86/core

[linux-2.6-omap-h63xx.git] / arch / x86 / kernel / signal_64.c

diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c
index 47c3d249e638efdf72395cb2f269f8bcf63a5576..2f14640500599f091720ab69ec61d44c072a7ebc 100644 (file)
--- a/arch/x86/kernel/signal_64.c
+++ b/arch/x86/kernel/signal_64.c
@@ -26,6 +26,7 @@
 #include <asm/proto.h>
 #include <asm/ia32_unistd.h>
 #include <asm/mce.h>
+#include <asm/syscalls.h>
 #include "sigframe.h"
 
 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
@@ -53,6 +54,68 @@ sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
        return do_sigaltstack(uss, uoss, regs->sp);
 }
 
+/*
+ * Signal frame handlers.
+ */
+
+static inline int save_i387(struct _fpstate __user *buf)
+{
+       struct task_struct *tsk = current;
+       int err = 0;
+
+       BUILD_BUG_ON(sizeof(struct user_i387_struct) !=
+                       sizeof(tsk->thread.xstate->fxsave));
+
+       if ((unsigned long)buf % 16)
+               printk("save_i387: bad fpstate %p\n", buf);
+
+       if (!used_math())
+               return 0;
+       clear_used_math(); /* trigger finit */
+       if (task_thread_info(tsk)->status & TS_USEDFPU) {
+               err = save_i387_checking((struct i387_fxsave_struct __user *)
+                                        buf);
+               if (err)
+                       return err;
+               task_thread_info(tsk)->status &= ~TS_USEDFPU;
+               stts();
+       } else {
+               if (__copy_to_user(buf, &tsk->thread.xstate->fxsave,
+                                  sizeof(struct i387_fxsave_struct)))
+                       return -1;
+       }
+       return 1;
+}
+
+/*
+ * This restores directly out of user space. Exceptions are handled.
+ */
+static inline int restore_i387(struct _fpstate __user *buf)
+{
+       struct task_struct *tsk = current;
+       int err;
+
+       if (!used_math()) {
+               err = init_fpu(tsk);
+               if (err)
+                       return err;
+       }
+
+       if (!(task_thread_info(current)->status & TS_USEDFPU)) {
+               clts();
+               task_thread_info(current)->status |= TS_USEDFPU;
+       }
+       err = restore_fpu_checking((__force struct i387_fxsave_struct *)buf);
+       if (unlikely(err)) {
+               /*
+                * Encountered an error while doing the restore from the
+                * user buffer, clear the fpu state.
+                */
+               clear_fpu(tsk);
+               clear_used_math();
+       }
+       return err;
+}
 
 /*
  * Do a signal return; undo the signal stack.