We currently decide whether we need to descend into the subdirs of
drivers/ in drivers/Makefile, but link the resulting objects from
the top-level Makefile.

Making these two decisions at the same time (in drivers/Makefile) cleans
up the top-level Makefile quite a bit.

Link order does not change at all apart from sound/, which is now linked
last.

Many Makefiles did a put an own rule in front of 
"include $(TOPDIR)/Rules.make" for no good reason at all,
the only places where it made sense are converted to using
EXTRA_TARGETS now.

Use "make BUILD_MODULES=1 {,bzImage,zImage,vmlinux,...}" to build
your kernel - and it'll also build the modules as you go.

99% of the Makefiles are very simple target-wise:

o build modules as listed in $(obj-m) and 
o build $(L_TARGET)/$(O_TARGET) as a composite object containing $(obj-y)

However, there is one exception: typically arch/$ARCH/kernel Makefile
wants the same as above, plus
o build init_task.o, head.o, using the standard rules for built-in
  targets - i.e. they are supposed to be built in the same way as all
  the other targets listed in $(obj-y), but they should not be linked
  into arch/$ARCH/kernel/$(O_TARGET). Instead they'll be linked in
  directly in the final vmlinux link.

Currently this is achieved by overriding Rules.make's first_rule in 
arch/$ARCH/kernel/Makefile. This rather ad-hoc way relies on the knowing
how Rules.make works internally and at the same time does things behind
Rules.make's back. 

To clean this up, I'm introducing a new variable, supposed to be only
used in arch/$ARCH/kernel/Makefile:

$(EXTRA_TARGETS) can be used to declare additional objects which shall
be built in the current directory (using the flags for built-in objects),
but not linked into $(O_TARGET)/$(L_TARGET)

This patch only converts arch/i386/kernel/Makefile at this time, other
archs work the same way as before.

Apart from this, this patch also removes some "unexport ..." statements,
which are unnecessary since not exporting variables is the default and
renames the internal "all_targets" to "vmlinux", since it's actually
need for building vmlinux.

include/linux/compile.h is a generated file, only init/Makefile knows 
about it - including it outside of init/* will cause trouble on
parallel builds.

Also, when compile.h already exists when 'make dep' is run, that'll pick
up a dependency on $(TOPDIR)/include/linux/compile.h. So init/Makefile
needs to tell make that this is actually the same file as 
../include/linux.compile.h

into home.transmeta.com:/home/torvalds/v2.5/linux

So I missed at least one file which still relied on implicitly exporting
symbols. Now fixed.

The following allows the ramdisk to work on 2.5.18; maybe we need a
comment in do_open() ?

If d_splice_alias() doesn't find the alias dentry, it returns NULL.
Then, msdos_lookup() dereference the NULL, and Oopses. Fixed here.

The vfat_lookup() part is cleanup only.

FORCE is the de-facto standard name for a prequisite to force
recompilation, so instead of using a mix of 'dummy','FORCE' and
'FORCE_RECOMPILE' use 'FORCE' everywhere.

Also, move figuring out the path relative to the top level dir
into Rules.make, instead of calling an external script. 

It's possible to say "make <subdir>", to descend into that subdir
and recursively build things there. This patch provides this
facility generally without the arch Makefiles needing to duplicate
it for arch/$(ARCH)/somedir.

We now have the information which objects are being built
modular / built-in in Rules.make, so use this information instead
of passing flags to the sub makes.

into tiger.hpl.hp.com:/data1/bk/lia64/to-linus-2.5

ia64_switch_mode().

Didn't get the net/ conversion quite right, and apparently overlooked
one subdir in sound/. Now fixed.

Use the new

	obj-$(CONFIG_FOO) += foo/

syntax to descend into a subdir and link in the result, if
CONFIG_FOO=y.

Build the headers only when we need them during the build, not always
at 'make dep' time.

We use O_TARGET everywhere else, so let's just convert the remaining
users (They get the implicit built-in.o O_TARGET now)

(plus a bit of rearranging in the ISDN Makefiles) 

If a Makefile defines neither O_TARGET nor L_TARGET, let's assume a
default of 'built-in.o'. The goal of this is, of course, to eventually
get rid of O_TARGET completely.

 - move the contents of bdev_get_queue() into do_open() and
   check_partitions() and cache the result in new field of struct
   block_device

 - clean it at the same places that reset ->bd_op, etc.

 - make bdev_get_queue() return cached pointer.

 - kill the last caller of get_hardsect_size() (switching it to
   bdev_hardsect_size()).

 - kill blk_get_queue() and switching to bdev_get_queue()

into home.transmeta.com:/home/torvalds/v2.5/linux

  - make sure return codes are negative (i.e. return -ENOMEM and not return ENOMEM et al)

into home.transmeta.com:/home/torvalds/v2.5/linux

into home.transmeta.com:/home/torvalds/v2.5/linux

Fixes a warning in ieee1394_types.h and an error in include/linux/usb.h

into tp1.ruhr-uni-bochum.de:/home/kai/kernel/v2.5/linux-2.5.misc