UAPI: Partition the header include path sets and add uapi/ header directories

Partition the header include path flags into two sets, one for kernelspace
builds and one for userspace builds.

Add the following directories to build after the ordinary include directories
so that #include will pick up the UAPI header directly if the kernel header
has been moved there.

The userspace set (represented by the USERINCLUDE make variable) contains:

	-I $(srctree)/arch/$(hdr-arch)/include/uapi
	-I arch/$(hdr-arch)/include/generated/uapi
	-I $(srctree)/include/uapi
	-I include/generated/uapi
	-include $(srctree)/include/linux/kconfig.h

and the kernelspace set (represented by the LINUXINCLUDE make variable)
contains:

	-I $(srctree)/arch/$(hdr-arch)/include
	-I arch/$(hdr-arch)/include/generated
	-I $(srctree)/include
	-I include		--- if not building in the source tree

plus everything in the USERINCLUDE set.

Then use USERINCLUDE in building the x86 boot code.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>

7 files changed, 30 insertions, 9 deletions

diff --git a/Makefile b/Makefile
index 846dd7607854..da1707c3904b 100644
--- a/Makefile
+++ b/Makefile
@@ -350,12 +350,22 @@ AFLAGS_KERNEL	=
 CFLAGS_GCOV     = -fprofile-arcs -ftest-coverage
 
 
+# Use USERINCLUDE when you must reference the UAPI directories only.
+USERINCLUDE    := \
+                -I$(srctree)/arch/$(hdr-arch)/include/uapi \
+                -Iarch/$(hdr-arch)/include/generated/uapi \
+                -I$(srctree)/include/uapi \
+                -Iinclude/generated/uapi \
+                -include $(srctree)/include/linux/kconfig.h
+
 # Use LINUXINCLUDE when you must reference the include/ directory.
 # Needed to be compatible with the O= option
-LINUXINCLUDE    := -I$(srctree)/arch/$(hdr-arch)/include \
-                   -Iarch/$(hdr-arch)/include/generated -Iinclude \
-                   $(if $(KBUILD_SRC), -I$(srctree)/include) \
-                   -include $(srctree)/include/linux/kconfig.h
+LINUXINCLUDE    := \
+                -I$(srctree)/arch/$(hdr-arch)/include \
+                -Iarch/$(hdr-arch)/include/generated \
+                $(if $(KBUILD_SRC), -I$(srctree)/include) \
+                -Iinclude \
+                $(USERINCLUDE)
 
 KBUILD_CPPFLAGS := -D__KERNEL__
 
diff --git a/arch/cris/Makefile b/arch/cris/Makefile
index 29c2ceb38a76..39dc7d00083e 100644
--- a/arch/cris/Makefile
+++ b/arch/cris/Makefile
@@ -23,7 +23,9 @@ mach-$(CONFIG_ETRAXFS) := fs
 
 ifneq ($(arch-y),)
 SARCH := arch-$(arch-y)
-inc := -Iarch/cris/include/$(SARCH)
+inc := -Iarch/cris/include/uapi/$(SARCH)
+inc += -Iarch/cris/include/$(SARCH)
+inc += -Iarch/cris/include/uapi/$(SARCH)/arch
 inc += -Iarch/cris/include/$(SARCH)/arch
 else
 SARCH :=
diff --git a/arch/um/Makefile b/arch/um/Makefile
index 097091059aaa..133f7de2a13d 100644
--- a/arch/um/Makefile
+++ b/arch/um/Makefile
@@ -66,7 +66,9 @@ USER_CFLAGS = $(patsubst $(KERNEL_DEFINES),,$(patsubst -D__KERNEL__,,\
 include $(srctree)/$(ARCH_DIR)/Makefile-os-$(OS)
 
 KBUILD_CPPFLAGS += -I$(srctree)/$(HOST_DIR)/include \
-                   -I$(HOST_DIR)/include/generated
+                   -I$(srctree)/$(HOST_DIR)/include/uapi \
+                   -I$(HOST_DIR)/include/generated \
+                   -I$(HOST_DIR)/include/generated/uapi
 
 # -Derrno=kernel_errno - This turns all kernel references to errno into
 # kernel_errno to separate them from the libc errno.  This allows -fno-common
diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
index f7535bedc33f..ce03476d8c8f 100644
--- a/arch/x86/boot/Makefile
+++ b/arch/x86/boot/Makefile
@@ -37,7 +37,7 @@ setup-y		+= video-bios.o
 targets         += $(setup-y)
 hostprogs-y     := mkcpustr tools/build
 
-HOST_EXTRACFLAGS += -I$(srctree)/tools/include $(LINUXINCLUDE) \
+HOST_EXTRACFLAGS += -I$(srctree)/tools/include $(USERINCLUDE) \
                     -D__EXPORTED_HEADERS__
 
 $(obj)/cpu.o: $(obj)/cpustr.h
@@ -52,7 +52,7 @@ $(obj)/cpustr.h: $(obj)/mkcpustr FORCE
 
 # How to compile the 16-bit code.  Note we always compile for -march=i386,
 # that way we can complain to the user if the CPU is insufficient.
-KBUILD_CFLAGS   := $(LINUXINCLUDE) -g -Os -D_SETUP -D__KERNEL__ \
+KBUILD_CFLAGS   := $(USERINCLUDE) -g -Os -D_SETUP -D__KERNEL__ \
                    -DDISABLE_BRANCH_PROFILING \
                    -Wall -Wstrict-prototypes \
                    -march=i386 -mregparm=3 \
diff --git a/arch/x86/boot/mkcpustr.c b/arch/x86/boot/mkcpustr.c
index 919257f526f2..4579eff0ef4d 100644
--- a/arch/x86/boot/mkcpustr.c
+++ b/arch/x86/boot/mkcpustr.c
@@ -15,6 +15,8 @@
 
 #include <stdio.h>
 
+#include "../include/asm/required-features.h"
+#include "../include/asm/cpufeature.h"
 #include "../kernel/cpu/capflags.c"
 
 int main(void)
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index 16cae425d1f8..8c297aa53eef 100644
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -4,7 +4,9 @@
 #ifndef _ASM_X86_CPUFEATURE_H
 #define _ASM_X86_CPUFEATURE_H
 
+#ifndef _ASM_X86_REQUIRED_FEATURES_H
 #include <asm/required-features.h>
+#endif
 
 #define NCAPINTS        10      /* N 32-bit words worth of info */
 
diff --git a/arch/x86/kernel/cpu/mkcapflags.pl b/arch/x86/kernel/cpu/mkcapflags.pl
index c7b3fe2d72e0..091972ef49de 100644
--- a/arch/x86/kernel/cpu/mkcapflags.pl
+++ b/arch/x86/kernel/cpu/mkcapflags.pl
@@ -8,7 +8,10 @@
 open(IN, "< $in\0")   or die "$0: cannot open: $in: $!\n";
 open(OUT, "> $out\0") or die "$0: cannot create: $out: $!\n";
 
-print OUT "#include <asm/cpufeature.h>\n\n";
+print OUT "#ifndef _ASM_X86_CPUFEATURE_H\n";
+print OUT "#include <asm/cpufeature.h>\n";
+print OUT "#endif\n";
+print OUT "\n";
 print OUT "const char * const x86_cap_flags[NCAPINTS*32] = {\n";
 
 %features = ();