Commit 791a9a66 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'kbuild-uapi-v4.12' of... 

Merge tag 'kbuild-uapi-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild UAPI updates from Masahiro Yamada:
 "Improvement of headers_install by Nicolas Dichtel.

  It has been long since the introduction of uapi directories, but the
  de-coupling of exported headers has not been completed. Headers listed
  in header-y are exported whether they exist in uapi directories or
  not. His work fixes this inconsistency.

  All (and only) headers under uapi directories are now exported. The
  asm-generic wrappers are still exceptions, but this is a big step
  forward"

* tag 'kbuild-uapi-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  arch/include: remove empty Kbuild files
  uapi: export all arch specifics directories
  uapi: export all headers under uapi directories
  smc_diag.h: fix include from userland
  btrfs_tree.h: fix include from userland
  uapi: includes linux/types.h before exporting files
  Makefile.headersinst: remove destination-y option
  Makefile.headersinst: cleanup input files
  x86: stop exporting msr-index.h to userland
  nios2: put setup.h in uapi
  h8300: put bitsperlong.h in uapi
parents 23ea3f62 3e18c637

Documentation/kbuild/makefiles.txt

+31 −43
Original line number Diff line number Diff line
@@ -44,11 +44,11 @@ This document describes the Linux kernel Makefiles. 
	   --- 6.11 Post-link pass



	=== 7 Kbuild syntax for exported headers

		--- 7.1 header-y

		--- 7.1 no-export-headers

		--- 7.2 genhdr-y

		--- 7.3 destination-y

		--- 7.4 generic-y

		--- 7.5 generated-y

		--- 7.3 generic-y

		--- 7.4 generated-y

		--- 7.5 mandatory-y



	=== 8 Kbuild Variables

	=== 9 Makefile language
@@ -1236,7 +1236,7 @@ When kbuild executes, the following steps are followed (roughly): 
	that may be shared between individual architectures.

	The recommended approach how to use a generic header file is

	to list the file in the Kbuild file.

	See "7.4 generic-y" for further info on syntax etc.

	See "7.3 generic-y" for further info on syntax etc.



--- 6.11 Post-link pass
@@ -1263,53 +1263,32 @@ The pre-processing does: 
- drop include of compiler.h

- drop all sections that are kernel internal (guarded by ifdef __KERNEL__)



Each relevant directory contains a file name "Kbuild" which specifies the

headers to be exported.

See subsequent chapter for the syntax of the Kbuild file.



	--- 7.1 header-y



	header-y specifies header files to be exported.



		Example:

			#include/linux/Kbuild

			header-y += usb/

			header-y += aio_abi.h

All headers under include/uapi/, include/generated/uapi/,

arch/<arch>/include/uapi/ and arch/<arch>/include/generated/uapi/

are exported.



	The convention is to list one file per line and

	preferably in alphabetic order.

A Kbuild file may be defined under arch/<arch>/include/uapi/asm/ and

arch/<arch>/include/asm/ to list asm files coming from asm-generic.

See subsequent chapter for the syntax of the Kbuild file.



	header-y also specifies which subdirectories to visit.

	A subdirectory is identified by a trailing '/' which

	can be seen in the example above for the usb subdirectory.

	--- 7.1 no-export-headers



	Subdirectories are visited before their parent directories.

	no-export-headers is essentially used by include/uapi/linux/Kbuild to

	avoid exporting specific headers (e.g. kvm.h) on architectures that do

	not support it. It should be avoided as much as possible.



	--- 7.2 genhdr-y



	genhdr-y specifies generated files to be exported.

	Generated files are special as they need to be looked

	up in another directory when doing 'make O=...' builds.

	genhdr-y specifies asm files to be generated.



		Example:

			#include/linux/Kbuild

			genhdr-y += version.h

			#arch/x86/include/uapi/asm/Kbuild

			genhdr-y += unistd_32.h

			genhdr-y += unistd_64.h

			genhdr-y += unistd_x32.h



	--- 7.3 destination-y



	When an architecture has a set of exported headers that needs to be

	exported to a different directory destination-y is used.

	destination-y specifies the destination directory for all exported

	headers in the file where it is present.



		Example:

			#arch/xtensa/platforms/s6105/include/platform/Kbuild

			destination-y := include/linux



	In the example above all exported headers in the Kbuild file

	will be located in the directory "include/linux" when exported.



	--- 7.4 generic-y

	--- 7.3 generic-y



	If an architecture uses a verbatim copy of a header from

	include/asm-generic then this is listed in the file
@@ -1336,7 +1315,7 @@ See subsequent chapter for the syntax of the Kbuild file. 
		Example: termios.h

			#include <asm-generic/termios.h>



	--- 7.5 generated-y

	--- 7.4 generated-y



	If an architecture generates other header files alongside generic-y

	wrappers, and not included in genhdr-y, then generated-y specifies
@@ -1349,6 +1328,15 @@ See subsequent chapter for the syntax of the Kbuild file. 
			#arch/x86/include/asm/Kbuild

			generated-y += syscalls_32.h



	--- 7.5 mandatory-y



	mandatory-y is essentially used by include/uapi/asm-generic/Kbuild.asm

	to define the minimun set of headers that must be exported in

	include/asm.



	The convention is to list one subdir per line and

	preferably in alphabetic order.



=== 8 Kbuild Variables



The top Makefile exports the following variables:

Makefile

+3 −3
Original line number Diff line number Diff line
@@ -1142,7 +1142,7 @@ firmware_install: 
export INSTALL_HDR_PATH = $(objtree)/usr



# If we do an all arch process set dst to asm-$(hdr-arch)

hdr-dst = $(if $(KBUILD_HEADERS), dst=include/asm-$(hdr-arch), dst=include/asm)

hdr-dst = $(if $(KBUILD_HEADERS), dst=include/arch-$(hdr-arch), dst=include)



PHONY += archheaders

archheaders:
@@ -1163,7 +1163,7 @@ headers_install: __headers 
	$(if $(wildcard $(srctree)/arch/$(hdr-arch)/include/uapi/asm/Kbuild),, \

	  $(error Headers not exportable for the $(SRCARCH) architecture))

	$(Q)$(MAKE) $(hdr-inst)=include/uapi

	$(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst)

	$(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi $(hdr-dst)



PHONY += headers_check_all

headers_check_all: headers_install_all
@@ -1172,7 +1172,7 @@ headers_check_all: headers_install_all 
PHONY += headers_check

headers_check: headers_install

	$(Q)$(MAKE) $(hdr-inst)=include/uapi HDRCHECK=1

	$(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst) HDRCHECK=1

	$(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/ $(hdr-dst) HDRCHECK=1



# ---------------------------------------------------------------------------

# Kernel selftest

arch/alpha/include/uapi/asm/Kbuild

+0 −41
Original line number Diff line number Diff line 
# UAPI Header export list

include include/uapi/asm-generic/Kbuild.asm
 


header-y += a.out.h

header-y += auxvec.h

header-y += bitsperlong.h

header-y += byteorder.h

header-y += compiler.h

header-y += console.h

header-y += errno.h

header-y += fcntl.h

header-y += fpu.h

header-y += gentrap.h

header-y += ioctl.h

header-y += ioctls.h

header-y += ipcbuf.h

header-y += kvm_para.h

header-y += mman.h

header-y += msgbuf.h

header-y += pal.h

header-y += param.h

header-y += poll.h

header-y += posix_types.h

header-y += ptrace.h

header-y += reg.h

header-y += regdef.h

header-y += resource.h

header-y += sembuf.h

header-y += setup.h

header-y += shmbuf.h

header-y += sigcontext.h

header-y += siginfo.h

header-y += signal.h

header-y += socket.h

header-y += sockios.h

header-y += stat.h

header-y += statfs.h

header-y += swab.h

header-y += sysinfo.h

header-y += termbits.h

header-y += termios.h

header-y += types.h

header-y += unistd.h

arch/arc/include/uapi/asm/Kbuild

+0 −3
Original line number Diff line number Diff line 
# UAPI Header export list

include include/uapi/asm-generic/Kbuild.asm
 
header-y += elf.h

header-y += page.h

header-y += cachectl.h

arch/arm/include/uapi/asm/Kbuild

+0 −17
Original line number Diff line number Diff line 
# UAPI Header export list

include include/uapi/asm-generic/Kbuild.asm



header-y += auxvec.h

header-y += byteorder.h

header-y += fcntl.h

header-y += hwcap.h

header-y += ioctls.h

header-y += kvm_para.h

header-y += mman.h

header-y += perf_regs.h

header-y += posix_types.h

header-y += ptrace.h

header-y += setup.h

header-y += sigcontext.h

header-y += signal.h

header-y += stat.h

header-y += statfs.h

header-y += swab.h

header-y += unistd.h

genhdr-y += unistd-common.h

genhdr-y += unistd-oabi.h

genhdr-y += unistd-eabi.h