Originally, generated-y and genhdr-y had different meaning, like
follows:

- generated-y: generated headers (other than asm-generic wrappers)
- header-y   : headers to be exported
- genhdr-y   : generated headers to be exported (generated-y + header-y)

Since commit fcc8487d477a ("uapi: export all headers under uapi
directories"), headers under UAPI directories are all exported.
So, there is no more difference between generated-y and genhdr-y.

We see two users of genhdr-y, arch/{arm,x86}/include/uapi/asm/Kbuild.
They generate some headers in arch/{arm,x86}/include/generated/uapi/asm
directories, which are obviously exported.

Replace them with generated-y, and abolish genhdr-y.

Change-Id: I9b8b97c39673e93e3d1215090f31d68beffddbd7
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Git-Commit: ae3f4151737d2aad271e5b1f2553c5d56e52850c
Git-Repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[bharad@codeaurora.org: resolve trivial merge conflicts]
Signed-off-by: Naitik Bharadiya <bharad@codeaurora.org>
[schikk@codeaurora.org: resolve trivial merge conflicts]
Signed-off-by: Swetha Chikkaboraiah <schikk@codeaurora.org>

When a header file is removed from generic-y (often accompanied by the
addition of an arch specific header), the generated wrapper file will
persist, and in some cases may still take precedence over the new arch
header.

For example commit f1fe2d21f4e1 ("MIPS: Add definitions for extended
context") removed ucontext.h from generic-y in arch/mips/include/asm/,
and added an arch/mips/include/uapi/asm/ucontext.h. The continued use of
the wrapper when reusing a dirty build tree resulted in build failures
in arch/mips/kernel/signal.c:

arch/mips/kernel/signal.c: In function ‘sc_to_extcontext’:
arch/mips/kernel/signal.c:142:12: error: ‘struct ucontext’ has no member named ‘uc_extcontext’
  return &uc->uc_extcontext;
            ^
Fix by detecting and removing wrapper headers in generated header
directories that do not correspond to a filename in generic-y, genhdr-y,
or the newly introduced generated-y.

Change-Id: I405714f5ee734a83417b9b5082237867ffb58902
Reported-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Reported-by: Hauke Mehrtens <hauke@hauke-m.de>
Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-kbuild@vger.kernel.org
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Michal Marek <mmarek@suse.com>
Link: http://lkml.kernel.org/r/1466808144-23209-3-git-send-email-james.hogan@imgtec.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Git-commit: cda2c65f981d0c29805fd01ffce441c650ffe6cf
Git-repo: https://source.codeaurora.org/quic/la/kernel/msm-4.14/
Signed-off-by: Swetha Chikkaboraiah <schikk@codeaurora.org>

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

Several arch/*/include/uapi/asm/* header simply include the
corresponding <asm-generic/*> file. This patch allows such files to be
specified in uapi/asm/Kbuild via "generic-y += ..." to be automatically
generated (similar to asm/Kbuild).

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>

This patch silences a Makefile.asm-generic message
by defining a dummy rule for all.

make -f /usr/src/git/scripts/Makefile.asm-generic \
            obj=arch/x86/include/generated/asm
make[1]: Nothing to be done for `all'.

Signed-off-by: Peter Foley <pefoley2@verizon.net>
Signed-off-by: Michal Marek <mmarek@suse.cz>

Do nothing if arch/$(SRCARCH)/include/asm/Kbuild does not exist, which
is the case of um.

Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Sam Ravnborg <sam@ravnborg.org>

There is an increasing amount of header files
shared between individual architectures in asm-generic.
To avoid a lot of dummy wrapper files that just
include the corresponding file in asm-generic provide
some basic support in kbuild for this.

With the following patch an architecture can maintain
a list of files in the file arch/$(ARCH)/include/asm/Kbuild

To use a generic file just add:

        generic-y += <name-of-header-file.h>

For each file listed kbuild will generate the necessary
wrapper in arch/$(ARCH)/include/generated/asm.

When installing userspace headers a wrapper is likewise created.

The original inspiration for this came from the unicore32
patchset - although a different method is used.

The patch includes several improvements from Arnd Bergmann.
Michael Marek contributed Makefile.asm-generic.

Remis Baima did an intial implementation along to achive
the same - see https://patchwork.kernel.org/patch/13352/

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Guan Xuetao <guanxuetao@mprc.pku.edu.cn>
Tested-by: Guan Xuetao <guanxuetao@mprc.pku.edu.cn>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Remis Lima Baima <remis.developer@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>