x86/fpu: Move various internal function prototypes to fpu/internal.h

There are a number of FPU internal function prototypes and an inline function
in fpu/api.h, mostly placed so historically as the code grew over the years.

Move them over into fpu/internal.h where they belong. (Add sched.h include
to stackprotector.h which incorrectly relied on getting it from fpu/api.h.)

fpu/api.h is now a pure file that only contains FPU APIs intended for driver
use.
Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/include/asm/fpu/api.h

@@ -10,23 +10,8 @@
 #ifndef _ASM_X86_FPU_API_H
 #define _ASM_X86_FPU_API_H
 
-#include <linux/sched.h>
 #include <linux/hardirq.h>
 
-struct pt_regs;
-struct user_i387_struct;
-
-extern int fpstate_alloc_init(struct fpu *fpu);
-extern void fpstate_init(struct fpu *fpu);
-extern void fpu__clear(struct task_struct *tsk);
-
-extern int dump_fpu(struct pt_regs *, struct user_i387_struct *);
-extern void fpu__restore(void);
-extern void fpu__init_check_bugs(void);
-extern void fpu__resume_cpu(void);
-
-extern bool irq_fpu_usable(void);
-
 /*
  * Careful: __kernel_fpu_begin/end() must be called with preempt disabled
  * and they don't touch the preempt state on their own.
@@ -41,6 +26,7 @@ extern void __kernel_fpu_begin(void);
 extern void __kernel_fpu_end(void);
 extern void kernel_fpu_begin(void);
 extern void kernel_fpu_end(void);
+extern bool irq_fpu_usable(void);
 
 /*
  * Some instructions like VIA's padlock instructions generate a spurious
@@ -73,19 +59,4 @@ static inline void irq_ts_restore(int TS_state)
 		stts();
 }
 
-/*
- * The question "does this thread have fpu access?"
- * is slightly racy, since preemption could come in
- * and revoke it immediately after the test.
- *
- * However, even in that very unlikely scenario,
- * we can just assume we have FPU access - typically
- * to save the FP state - we'll just take a #NM
- * fault and get the FPU access back.
- */
-static inline int user_has_fpu(void)
-{
-	return current->thread.fpu.fpregs_active;
-}
-
 #endif /* _ASM_X86_FPU_API_H */

arch/x86/include/asm/fpu/internal.h

@@ -12,6 +12,7 @@
 
 #include <linux/regset.h>
 #include <linux/compat.h>
+#include <linux/sched.h>
 #include <linux/slab.h>
 
 #include <asm/user.h>
@@ -43,6 +44,15 @@ extern void fpu__init_system_xstate(void);
 extern void fpu__init_cpu_xstate(void);
 extern void fpu__init_system(struct cpuinfo_x86 *c);
 
+extern int fpstate_alloc_init(struct fpu *fpu);
+extern void fpstate_init(struct fpu *fpu);
+extern void fpu__clear(struct task_struct *tsk);
+
+extern int dump_fpu(struct pt_regs *, struct user_i387_struct *);
+extern void fpu__restore(void);
+extern void fpu__init_check_bugs(void);
+extern void fpu__resume_cpu(void);
+
 DECLARE_PER_CPU(struct fpu *, fpu_fpregs_owner_ctx);
 
 extern void convert_from_fxsr(struct user_i387_ia32_struct *env,
@@ -334,6 +344,21 @@ static inline void __fpregs_activate(struct fpu *fpu)
 	this_cpu_write(fpu_fpregs_owner_ctx, fpu);
 }
 
+/*
+ * The question "does this thread have fpu access?"
+ * is slightly racy, since preemption could come in
+ * and revoke it immediately after the test.
+ *
+ * However, even in that very unlikely scenario,
+ * we can just assume we have FPU access - typically
+ * to save the FP state - we'll just take a #NM
+ * fault and get the FPU access back.
+ */
+static inline int user_has_fpu(void)
+{
+	return current->thread.fpu.fpregs_active;
+}
+
 /*
  * Encapsulate the CR0.TS handling together with the
  * software flag.

arch/x86/include/asm/stackprotector.h

@@ -39,7 +39,9 @@
 #include <asm/processor.h>
 #include <asm/percpu.h>
 #include <asm/desc.h>
+
 #include <linux/random.h>
+#include <linux/sched.h>
 
 /*
  * 24 byte read-only segment initializer for stack canary.  Linker

arch/x86/kernel/cpu/bugs.c

@@ -12,7 +12,7 @@
 #include <asm/bugs.h>
 #include <asm/processor.h>
 #include <asm/processor-flags.h>
-#include <asm/fpu/api.h>
+#include <asm/fpu/internal.h>
 #include <asm/msr.h>
 #include <asm/paravirt.h>
 #include <asm/alternative.h>

arch/x86/kvm/vmx.c

@@ -40,7 +40,7 @@
 #include <asm/vmx.h>
 #include <asm/virtext.h>
 #include <asm/mce.h>
-#include <asm/fpu/api.h>
+#include <asm/fpu/internal.h>
 #include <asm/xcr.h>
 #include <asm/perf_event.h>
 #include <asm/debugreg.h>

arch/x86/math-emu/fpu_entry.c

@@ -31,7 +31,7 @@
 #include <asm/traps.h>
 #include <asm/desc.h>
 #include <asm/user.h>
-#include <asm/fpu/api.h>
+#include <asm/fpu/internal.h>
 
 #include "fpu_system.h"
 #include "fpu_emu.h"

arch/x86/power/cpu.c

@@ -19,6 +19,7 @@
 #include <asm/page.h>
 #include <asm/mce.h>
 #include <asm/suspend.h>
+#include <asm/fpu/internal.h>
 #include <asm/debugreg.h>
 #include <asm/cpu.h>
 

drivers/lguest/x86/core.c

@@ -46,7 +46,7 @@
 #include <asm/setup.h>
 #include <asm/lguest.h>
 #include <asm/uaccess.h>
-#include <asm/fpu/api.h>
+#include <asm/fpu/internal.h>
 #include <asm/tlbflush.h>
 #include "../lg.h"