Adds README file, TODO list, and a couple of other pieces that didn't seem
to fit into any other patch.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Minimal functionality...
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

The OpenRISC Linux kernel conforms to the "generic" syscall interface which
contains only the reduced set of syscalls deemed necessary for new
architectures.  Unfortunately, the uClibc port for OpenRISC does not fully
support this reduced set; as such, an additional patch available out-of-tree
needs to be applied to the kernel in order to use the current uClibc.  This
is just a temporary measure until the libc port can be straightened out; it
is likely that OpenRISC will make the transition to glibc shortly where the
generic syscall interface is better supported.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

This patch adds support for the OpenRISC PIC.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Cc: tglx@linutronix.de
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Implements support for the OpenRISC timer which is a 28 bit cycle counter
that can be read out of a special purpose register.  This counter is
used as a both a clock event and clocksource device.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Cc: tglx@linutronix.de
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Simple DMA implementation.  Allows for allocation of coherent memory
(simply uncached) for DMA operations.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

This patch implements minimal PTrace support.  The pt_regs structure is
not exported to userspace for OpenRISC; rather, the GETREGSET mechanism
is intended to be used and the registers, as such, exported in the core
dump format which is ABI stable.  This is in line with what is intended
for new architectures as of 2.6.34 and has the advantage of permitting
the layout of the registers on the kernel stack (as per pt_regs) to be
freely modified.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

The OpenRISC architecture uses the device tree infrastructure for the
platform description.  This is currently limited to having a device tree
built into the kernel, but work is underway within the OpenRISC project
to define how this device tree blob should be passed into the kernel from
an external resource.

Patch contains a single example DTS file to go with the defconfig for
or1ksim.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Cc: devicetree-discuss@lists.ozlabs.org
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Architecture code and early setup routines for booting Linux.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Use the CONFIG_HAS_IOPORT and CONFIG_PCI options to decide whether or
not functions for mapping these areas are provided.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Acked-by: Arnd Bergmann <arnd@arndb.de>

Some of the implementations, in particular the ioremap variants, in
asm-generic/io.h are for systems without an MMU.  In order to be able to
use the generic header file for systems with an MMU, this patch wraps
these implementations in checks for CONFIG_MMU.

Tested on OpenRISC.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Cc: liqin.chen@sunplusct.com
Cc: gxt@mprc.pku.edu.cn
Acked-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>

This patch moves the in-tree architectures that were using the 'generic'
delay.h over to using the header file in asm-generic.

This is not done using the generic-y mechanism as none of these arch's
have started using that mechanism yet.  This is a trivial change to make
later when the arch begins using generic-y.

Note the subtle change to the avr32 and SH architectures where the argument
to __const_udelay was previously using the rounded down constant value
instead of the rounded up value.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>

With a non-constant 8-bit argument, a call to udelay() generates a warning:

drivers/gpu/drm/radeon/atom.c: In function 'atom_op_delay':
drivers/gpu/drm/radeon/atom.c:654: warning: comparison is always false due to limited range of data type

The code looks like it works OK with an 8-bit arg, and the calling code is
doing nothing wrong, so udelay() needs fixing.

Fixing it was rather tricky.  Simply typecasting `n' in the comparison with
20000 didn't change anything.  Hence the divide-by-20000 trick.

Using a do{}while loop didn't work because udelay() is used in ?: statements,
hence the ({...}) construct.

While I was there I replaced the brain-bending ?:?:?: mess with nice if/else
code.

Probably other architectures are generating the same warning and can use a
similar change.

[Taken from the x86 tree and moved to asm-generic by Jonas Bonn]

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jonas Bonn <jonas@southpole.se>

Several architectures are using a common delay.h implementation that
appears to have originated with the x86 architecture.  This common
implementation is a bit fuller than the current asm-generic version
and has some compile-time checks that should be interesting for all
architectures.

This patch takes the common delay.h version and replaces the rather
trivial asm-generic version with it.  As no architecture was actually
using asm-generic/delay.h, this change is rather innocuous; it will,
however, allow us to switch at least four architectures over to using
the asm-generic version.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Acked-by: Arnd Bergmann <arnd@arndb.de>

When auditing the locking in i915_gem.c (for a prospective change which
I then abandoned), I noticed two places where struct_mutex is not held
across GEM object manipulations that would usually require it.

Since one is in initial setup and the other in driver unload, I'm
guessing the mutex is not required for either; but post a patch in case
it is.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Keith Packard <keithp@keithp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The interface to ->truncate_range is changing very slightly: once "tmpfs:
take control of its truncate_range" has been applied, this can be applied.
 For now there is only a slight inefficiency while this remains unapplied,
but it will soon become essential for managing shmem's use of swap.

Change i915_gem_object_truncate() to use shmem_truncate_range() directly:
which should also spare i915 later change if we switch from
inode_operations->truncate_range to file_operations->fallocate.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Keith Packard <keithp@keithp.com>
Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Soon tmpfs will stop supporting ->readpage and read_cache_page_gfp(): once
"tmpfs: add shmem_read_mapping_page_gfp" has been applied, this patch can
be applied to ease the transition.

Make i915_gem_object_get_pages_gtt() use shmem_read_mapping_page_gfp() in
the one place it's needed; elsewhere use shmem_read_mapping_page(), with
the mapping's gfp_mask properly initialized.

Forget about __GFP_COLD: since tmpfs initializes its pages with memset,
asking for a cold page is counter-productive.

Include linux/shmem_fs.h also in drm_gem.c: with shmem_file_setup() now
declared there too, we shall remove the prototype from linux/mm.h later.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Keith Packard <keithp@keithp.com>
Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Soon tmpfs will stop supporting ->readpage and read_mapping_page(): once
"tmpfs: add shmem_read_mapping_page_gfp" has been applied, this patch can
be applied to ease the transition.

ttm_tt_swapin() and ttm_tt_swapout() use shmem_read_mapping_page() in
place of read_mapping_page(), since their swap_space has been created with
shmem_file_setup().
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fis the warning

  drivers/tty/serial/8250_pci.c:1457: warning: initialization from incompatible pointer type

Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix this section mismatch:

  WARNING: drivers/misc/ioc4.o(.data+0x144): Section mismatch in reference from the variable ioc4_load_modules_work to the function .devinit.text:ioc4_load_modules()
  The variable ioc4_load_modules_work references
  the function __devinit ioc4_load_modules()
  If the reference is valid then annotate the
  variable with __init* or __refdata (see linux/init.h) or name the variable:
  *driver, *_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console

This one is potentially fatal; by the time ioc4_load_modules is invoked
it may already have been freed.  For that reason ioc4_load_modules_work
can't be turned to __devinitdata but also because it's referenced in
ioc4_exit.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Brent Casavant <bcasavan@sgi.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix this section mismatch:

  WARNING: drivers/leds/leds-lp5523.o(.text+0x12f4): Section mismatch in reference from the function lp5523_probe() to the function .init.text:lp5523_init_led()
  The function lp5523_probe() references
  the function __init lp5523_init_led().
  This is often because lp5523_probe lacks a __init
  annotation or the annotation of lp5523_init_led is wrong.

Fixing this one triggers one more mismatch, fix that one as well.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix this section mismatch:

  WARNING: drivers/leds/leds-lp5521.o(.text+0xf2c): Section mismatch in reference from the function lp5521_probe() to the function .init.text:lp5521_init_led()
  The function lp5521_probe() references
  the function __init lp5521_init_led().
  This is often because lp5521_probe lacks a __init
  annotation or the annotation of lp5521_init_led is wrong.

Fixing this mismatch triggers one more mismatch, fix that one as well.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit d149e3b2 ("memcg: add the soft_limit reclaim in global direct
reclaim") adds a softlimit hook to shrink_zones().  By this, soft limit
is called as

   try_to_free_pages()
       do_try_to_free_pages()
           shrink_zones()
               mem_cgroup_soft_limit_reclaim()

Then, direct reclaim is memcg softlimit hint aware, now.

But, the memory cgroup's "limit" path can call softlimit shrinker.

   try_to_free_mem_cgroup_pages()
       do_try_to_free_pages()
           shrink_zones()
               mem_cgroup_soft_limit_reclaim()

This will cause a global reclaim when a memcg hits limit.

This is bug. soft_limit_reclaim() should be called when
scanning_global_lru(sc) == true.

And the commit adds a variable "total_scanned" for counting softlimit
scanned pages....it's not "total".  This patch removes the variable and
update sc->nr_scanned instead of it.  This will affect shrink_slab()'s
scan condition but, global LRU is scanned by softlimit and I think this
change makes sense.

TODO: avoid too much scanning of a zone when softlimit did enough work.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Ying Han <yinghan@google.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Currently a single process may register exit handlers unlimited times.
It may lead to a bloated listeners chain and very slow process
terminations.

Eg after 10KK sent TASKSTATS_CMD_ATTR_REGISTER_CPUMASKs ~300 Mb of
kernel memory is stolen for the handlers chain and "time id" shows 2-7
seconds instead of normal 0.003.  It makes it possible to exhaust all
kernel memory and to eat much of CPU time by triggerring numerous exits
on a single CPU.

The patch limits the number of times a single process may register
itself on a single CPU to one.

One little issue is kept unfixed - as taskstats_exit() is called before
exit_files() in do_exit(), the orphaned listener entry (if it was not
explicitly deregistered) is kept until the next someone's exit() and
implicit deregistration in send_cpu_listeners().  So, if a process
registered itself as a listener exits and the next spawned process gets
the same pid, it would inherit taskstats attributes.
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Under heavy memory and filesystem load, users observe the assertion
mapping->nrpages == 0 in end_writeback() trigger.  This can be caused by
page reclaim reclaiming the last page from a mapping in the following
race:

	CPU0				CPU1
  ...
  shrink_page_list()
    __remove_mapping()
      __delete_from_page_cache()
        radix_tree_delete()
					evict_inode()
					  truncate_inode_pages()
					    truncate_inode_pages_range()
					      pagevec_lookup() - finds nothing
					  end_writeback()
					    mapping->nrpages != 0 -> BUG
        page->mapping = NULL
        mapping->nrpages--

Fix the problem by doing a reliable check of mapping->nrpages under
mapping->tree_lock in end_writeback().

Analyzed by Jay <jinshan.xiong@whamcloud.com>, lost in LKML, and dug out
by Miklos Szeredi <mszeredi@suse.de>.

Cc: Jay <jinshan.xiong@whamcloud.com>
Cc: Miklos Szeredi <mszeredi@suse.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We cannot take a mutex while holding a spinlock, so flip the order and
fix the locking documentation.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We observed the crash point count going negative in cases where the
crash point is hit multiple times before the check of "count == 0" is
done.  Because of this we never call lkdtm_do_action().  This patch just
adds a spinlock to protect count.
Reported-by: Tapan Dhimant <tdhimant@akamai.com>
Signed-off-by: Josh Hunt <johunt@akamai.com>
Acked-by: Ankita Garg <ankita@in.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This is required for tilegx to be able to use the compat unistd.h header
where compat_sys_sendmmsg() is now mentioned.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

romfs_get_unmapped_area() checks argument `len' without considering
PAGE_ALIGN which will cause do_mmap_pgoff() return -EINVAL error after
commit f67d9b15 ("nommu: add page_align to mmap").

Fix the check by changing it in same way ramfs_nommu_get_unmapped_area()
was changed in ramfs/file-nommu.c.
Signed-off-by: Bob Liu <lliubbo@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Acked-by: Greg Ungerer <gerg@snapgear.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

To make SLUB work on UML we need this_cpu_cmpxchg from
asm-generic/percpu.h.
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>