percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
This implements a fairly significant overhaul of the dynamic PMB mapping
code. The primary change here is that the PMB gets its own VMA that
follows the uncached mapping and we attempt to be a bit more intelligent
with dynamic sizing, multi-entry mapping, and so forth.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
iounmap_fixed() had a couple of bugs in it that caused it to effectively
fail at life. The total number of pages to unmap factored in the mapping
offset and aligned up to the next page boundary, which doesn't match the
ioremap_fixed() behaviour.
When ioremap_fixed() pegs a slot, the address in the mapping data already
contains the offset displacement, and the size is recorded verbatim given
that we're only interested in total number of pages required. As such, we
need to calculate the total number from the original size in the unmap
path as well.
At the same time, there was also an off-by-1 problem in the fixmap index
calculation which has also been corrected.
Previously subsequent remaps of an identical fixmap index would trigger
the pte_ERROR() in set_pte_phys():
arch/sh/mm/init.c:77: bad pte 8053ffb0(0000781003fff506).
arch/sh/mm/init.c:77: bad pte 8053ffb0(0000781003fff506).
arch/sh/mm/init.c:77: bad pte 8053ffb0(0000781003fff506).
arch/sh/mm/init.c:77: bad pte 8053ffb0(0000781003fff506).
arch/sh/mm/init.c:77: bad pte 8053ffb0(0000781003fff506).
arch/sh/mm/init.c:77: bad pte 8053ffb0(0000781003fff506).
With this patch in place, the iounmap-driven fixmap teardown actually
does what it's supposed to do.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This is already taken care of in the top-level ioremap, and now that
no one should be calling ioremap_fixed() directly we can simply throw the
mapping displacement in as an additional argument.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This converts iounmap_fixed() to return success/error if it handled the
unmap request or not. At the same time, drop the __init label, as this
can be called in to later.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Some devices need to be ioremap'd and accessed very early in the boot
process. It is not possible to use the standard ioremap() function in
this case because that requires kmalloc()'ing some virtual address space
and kmalloc() may not be available so early in boot.
This patch provides fixmap mappings that allow physical address ranges
to be remapped into the kernel address space during the early boot
stages.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
