Debian does not ship a 'mkisofs' symlink to genisoimage.  All modern
distros ship genisoimage, so just use that directly.  That requires
renaming the 'genisoimage' function.  Also neaten up the 'for' loop
while I'm in here.
Signed-off-by: NMatthew Wilcox <mawilcox@microsoft.com>
Cc: Changbin Du <changbin.du@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

If mtools.conf is not generated before, 'make isoimage' could complain:

  Kernel: arch/x86/boot/bzImage is ready  (#597)
    GENIMAGE arch/x86/boot/image.iso
   *** Missing file: arch/x86/boot/mtools.conf
  arch/x86/boot/Makefile:144: recipe for target 'isoimage' failed

mtools.conf is not used for isoimage generation, so do not check it.
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 4366d57a ("x86/build: Factor out fdimage/isoimage generation commands to standalone script")
Link: http://lkml.kernel.org/r/1512053480-8083-1-git-send-email-changbin.du@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This change suppresses the 'dd' output and adds the '-quiet' parameter
to mkisofs tool. It also removes the 'Using ...' messages, as none of the
messages matter to the user normally.

"make V=1" can still be used for a more verbose build.

The new build messages are now a streamlined set of:

  $ make isoimage
  ...
  Kernel: arch/x86/boot/bzImage is ready  (#75)
    GENIMAGE arch/x86/boot/image.iso
  Kernel: arch/x86/boot/image.iso is ready
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1510207751-22166-1-git-send-email-changbin.du@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

It avoids the following warning triggered by newer versions of mkisofs:

    -input-charset not specified, using utf-8 (detected in locale settings)
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: yamada.masahiro@socionext.com
Link: http://lkml.kernel.org/r/1509939179-7556-4-git-send-email-changbin.du@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Recently I failed to build isoimage target, because the path of isolinux.bin
changed to /usr/xxx/ISOLINUX/isolinux.bin, as well as ldlinux.c32 which
changed to /usr/xxx/syslinux/modules/bios/ldlinux.c32.

This patch improves the file search logic:
  - Show a error message instead of silent fail.
  - Add above new paths.
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: yamada.masahiro@socionext.com
Link: http://lkml.kernel.org/r/1509939179-7556-3-git-send-email-changbin.du@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The build messages for fdimage/isoimage generation are pretty unstructured,
just the raw shell command blocks are printed.

Emit shortened messages similar to existing kbuild messages, and move
the Makefile commands into a separate shell script - which is much
easier to handle.

This patch factors out the commands used for fdimage/isoimage generation
from arch/x86/boot/Makefile to a new script arch/x86/boot/genimage.sh.
Then it adds the new kbuild command 'genimage' which invokes the new script.
All fdimages/isoimage files are now generated by a call to 'genimage' with
different parameters.

Now 'make isoimage' becomes:

	...
	Kernel: arch/x86/boot/bzImage is ready  (#30)
	  GENIMAGE arch/x86/boot/image.iso
	Size of boot image is 4 sectors -> No emulation
	 15.37% done, estimate finish Sun Nov  5 23:36:57 2017
	 30.68% done, estimate finish Sun Nov  5 23:36:57 2017
	 46.04% done, estimate finish Sun Nov  5 23:36:57 2017
	 61.35% done, estimate finish Sun Nov  5 23:36:57 2017
	 76.69% done, estimate finish Sun Nov  5 23:36:57 2017
	 92.00% done, estimate finish Sun Nov  5 23:36:57 2017
	Total translation table size: 2048
	Total rockridge attributes bytes: 659
	Total directory bytes: 0
	Path table size(bytes): 10
	Max brk space used 0
	32608 extents written (63 MB)
	Kernel: arch/x86/boot/image.iso is ready

Before:

	Kernel: arch/x86/boot/bzImage is ready  (#63)
	rm -rf arch/x86/boot/isoimage
	mkdir arch/x86/boot/isoimage
	for i in lib lib64 share end ; do \
		if [ -f /usr/$i/syslinux/isolinux.bin ] ; then \
			cp /usr/$i/syslinux/isolinux.bin arch/x86/boot/isoimage ; \
			if [ -f /usr/$i/syslinux/ldlinux.c32 ]; then \
				cp /usr/$i/syslinux/ldlinux.c32 arch/x86/boot/isoimage ; \
			fi ; \
			break ; \
		fi ; \
		if [ $i = end ] ; then exit 1 ; fi ; \
	done
	...
Suggested-by: NIngo Molnar <mingo@kernel.org>
Signed-off-by: NChangbin Du <changbin.du@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1509939179-7556-2-git-send-email-changbin.du@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>