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17 years agocoredump masking: documentation for /proc/pid/coredump_filter
Kawai, Hidehiro [Thu, 19 Jul 2007 08:48:31 +0000 (01:48 -0700)]
coredump masking: documentation for /proc/pid/coredump_filter

This patch adds the documentation for /proc/<pid>/coredump_filter.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agocoredump masking: ELF-FDPIC: enable core dump filtering
Kawai, Hidehiro [Thu, 19 Jul 2007 08:48:30 +0000 (01:48 -0700)]
coredump masking: ELF-FDPIC: enable core dump filtering

This patch enables core dump filtering for ELF-FDPIC-formatted core file.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agocoredump masking: ELF-FDPIC: remove an unused argument
Kawai, Hidehiro [Thu, 19 Jul 2007 08:48:30 +0000 (01:48 -0700)]
coredump masking: ELF-FDPIC: remove an unused argument

This patch removes an unused argument from elf_fdpic_dump_segments().

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agocoredump masking: ELF: enable core dump filtering
Kawai, Hidehiro [Thu, 19 Jul 2007 08:48:29 +0000 (01:48 -0700)]
coredump masking: ELF: enable core dump filtering

This patch enables core dump filtering for ELF-formatted core file.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agocoredump masking: add an interface for core dump filter
Kawai, Hidehiro [Thu, 19 Jul 2007 08:48:28 +0000 (01:48 -0700)]
coredump masking: add an interface for core dump filter

This patch adds an interface to set/reset flags which determines each memory
segment should be dumped or not when a core file is generated.

/proc/<pid>/coredump_filter file is provided to access the flags.  You can
change the flag status for a particular process by writing to or reading from
the file.

The flag status is inherited to the child process when it is created.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agocoredump masking: reimplementation of dumpable using two flags
Kawai, Hidehiro [Thu, 19 Jul 2007 08:48:27 +0000 (01:48 -0700)]
coredump masking: reimplementation of dumpable using two flags

This patch changes mm_struct.dumpable to a pair of bit flags.

set_dumpable() converts three-value dumpable to two flags and stores it into
lower two bits of mm_struct.flags instead of mm_struct.dumpable.
get_dumpable() behaves in the opposite way.

[akpm@linux-foundation.org: export set_dumpable]
Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agocoredump masking: bound suid_dumpable sysctl
Kawai, Hidehiro [Thu, 19 Jul 2007 08:48:26 +0000 (01:48 -0700)]
coredump masking: bound suid_dumpable sysctl

This patch series is version 5 of the core dump masking feature, which
controls which VMAs should be dumped based on their memory types and
per-process flags.

I adopted most of Andrew's suggestion at the previous version.  He also
suggested using system call instead of /proc/<pid>/ interface, I decided to
use the latter continuously because adding new system call with pid argument
will give a big impact on the kernel.

You can access the per-process flags via /proc/<pid>/coredump_filter
interface.  coredump_filter represents a bitmask of memory types, and if a bit
is set, VMAs of corresponding memory type are written into a core file when
the process is dumped.  The bitmask is inherited from the parent process when
a process is created.

The original purpose is to avoid longtime system slowdown when a number of
processes which share a huge shared memory are dumped at the same time.  To
achieve this purpose, this patch series adds an ability to suppress dumping
anonymous shared memory for specified processes.  In this version, three other
memory types are also supported.

Here are the coredump_filter bits:
  bit 0: anonymous private memory
  bit 1: anonymous shared memory
  bit 2: file-backed private memory
  bit 3: file-backed shared memory

The default value of coredump_filter is 0x3.  This means the new core dump
routine has the same behavior as conventional behavior by default.

In this version, coredump_filter bits and mm.dumpable are merged into
mm.flags, and it is accessed by atomic bitops.

The supported core file formats are ELF and ELF-FDPIC.  ELF has been tested,
but ELF-FDPIC has not been built and tested because I don't have the test
environment.

This patch limits a value of suid_dumpable sysctl to the range of 0 to 2.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agodocbook: don't reference file without kernel-doc
Randy Dunlap [Thu, 19 Jul 2007 08:48:25 +0000 (01:48 -0700)]
docbook: don't reference file without kernel-doc

Remove include/linux/rmap.h from kernel-api.tmpl since it no longer
contains kernel-doc.  Fixes this warning:

Warning(linux-2.6.22//include/linux/rmap.h): no structured comments found

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agokernel-doc: fix leading dot in man-mode output
Randy Dunlap [Thu, 19 Jul 2007 08:48:25 +0000 (01:48 -0700)]
kernel-doc: fix leading dot in man-mode output

If a parameter description begins with a '.', this indicates a "request"
for "man" mode output (*roff), so it needs special handling.

Problem case is in include/asm-i386/atomic.h for function
atomic_add_unless():
 * @u: ...unless v is equal to u.
This parameter description is currently not printed in man mode output.

[akpm@linux-foundation.org: cleanup]
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agokernel-doc: strip C99 comments
Randy Dunlap [Thu, 19 Jul 2007 08:48:24 +0000 (01:48 -0700)]
kernel-doc: strip C99 comments

Strip C99-style comments from the input stream.
/*...*/ comments are already stripped.
C99 comments confuse the kernel-doc script.

Also update some comments.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agokernel-doc: fix unnamed struct/union warning
Randy Dunlap [Thu, 19 Jul 2007 08:48:24 +0000 (01:48 -0700)]
kernel-doc: fix unnamed struct/union warning

Fix kernel-doc warning:
Warning(linux-2.6.22-rc2-git2/include/linux/skbuff.h:316): No description found for parameter '}'

which is caused by nested anonymous structs/unions ending with:
  };
};

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agokernel-doc: add tools doc in Makefile
Randy Dunlap [Thu, 19 Jul 2007 08:48:23 +0000 (01:48 -0700)]
kernel-doc: add tools doc in Makefile

Add kernel-doc tools info in Makefile.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agofs: remove path_walk export
Josef 'Jeff' Sipek [Thu, 19 Jul 2007 08:48:22 +0000 (01:48 -0700)]
fs: remove path_walk export

Signed-off-by: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Neil Brown <neilb@suse.de>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agofs: mark link_path_walk static
Josef 'Jeff' Sipek [Thu, 19 Jul 2007 08:48:22 +0000 (01:48 -0700)]
fs: mark link_path_walk static

Signed-off-by: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Neil Brown <neilb@suse.de>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agonfsctl: use vfs_path_lookup
Josef 'Jeff' Sipek [Thu, 19 Jul 2007 08:48:21 +0000 (01:48 -0700)]
nfsctl: use vfs_path_lookup

use vfs_path_lookup instead of open-coding the necessary functionality.

Signed-off-by: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu>
Acked-by: NeilBrown <neilb@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agosunrpc: use vfs_path_lookup
Josef 'Jeff' Sipek [Thu, 19 Jul 2007 08:48:20 +0000 (01:48 -0700)]
sunrpc: use vfs_path_lookup

use vfs_path_lookup instead of open-coding the necessary functionality.

Signed-off-by: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Neil Brown <neilb@suse.de>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agofs: introduce vfs_path_lookup
Josef 'Jeff' Sipek [Thu, 19 Jul 2007 08:48:18 +0000 (01:48 -0700)]
fs: introduce vfs_path_lookup

Stackable file systems, among others, frequently need to lookup paths or
path components starting from an arbitrary point in the namespace
(identified by a dentry and a vfsmount).  Currently, such file systems use
lookup_one_len, which is frowned upon [1] as it does not pass the lookup
intent along; not passing a lookup intent, for example, can trigger BUG_ON's
when stacking on top of NFSv4.

The first patch introduces a new lookup function to allow lookup starting
from an arbitrary point in the namespace.  This approach has been suggested
by Christoph Hellwig [2].

The second patch changes sunrpc to use vfs_path_lookup.

The third patch changes nfsctl.c to use vfs_path_lookup.

The fourth patch marks link_path_walk static.

The fifth, and last patch, unexports path_walk because it is no longer
unnecessary to call it directly, and using the new vfs_path_lookup is
cleaner.

For example, the following snippet of code, looks up "some/path/component"
in a directory pointed to by parent_{dentry,vfsmnt}:

err = vfs_path_lookup(parent_dentry, parent_vfsmnt,
      "some/path/component", 0, &nd);
if (!err) {
/* exits */

...

/* once done, release the references */
path_release(&nd);
} else if (err == -ENOENT) {
/* doesn't exist */
} else {
/* other error */
}

VFS functions such as lookup_create can be used on the nameidata structure
to pass the create intent to the file system.

Signed-off-by: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Neil Brown <neilb@suse.de>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agomm: variable length argument support
Ollie Wild [Thu, 19 Jul 2007 08:48:16 +0000 (01:48 -0700)]
mm: variable length argument support

Remove the arg+env limit of MAX_ARG_PAGES by copying the strings directly from
the old mm into the new mm.

We create the new mm before the binfmt code runs, and place the new stack at
the very top of the address space.  Once the binfmt code runs and figures out
where the stack should be, we move it downwards.

It is a bit peculiar in that we have one task with two mm's, one of which is
inactive.

[a.p.zijlstra@chello.nl: limit stack size]
Signed-off-by: Ollie Wild <aaw@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <linux-arch@vger.kernel.org>
Cc: Hugh Dickins <hugh@veritas.com>
[bunk@stusta.de: unexport bprm_mm_init]
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoaudit: rework execve audit
Peter Zijlstra [Thu, 19 Jul 2007 08:48:15 +0000 (01:48 -0700)]
audit: rework execve audit

The purpose of audit_bprm() is to log the argv array to a userspace daemon at
the end of the execve system call.  Since user-space hasn't had time to run,
this array is still in pristine state on the process' stack; so no need to
copy it, we can just grab it from there.

In order to minimize the damage to audit_log_*() copy each string into a
temporary kernel buffer first.

Currently the audit code requires that the full argument vector fits in a
single packet.  So currently it does clip the argv size to a (sysctl) limit,
but only when execve auditing is enabled.

If the audit protocol gets extended to allow for multiple packets this check
can be removed.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ollie Wild <aaw@google.com>
Cc: <linux-audit@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoarch: personality independent stack top
Peter Zijlstra [Thu, 19 Jul 2007 08:48:14 +0000 (01:48 -0700)]
arch: personality independent stack top

New arch macro STACK_TOP_MAX it gives the larges valid stack address for the
architecture in question.

It differs from STACK_TOP in that it will not distinguish between
personalities but will always return the largest possible address.

This is used to create the initial stack on execve, which we will move down to
the proper location once the binfmt code has figured out where that is.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ollie Wild <aaw@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agouse the new percpu interface for shared data
Fenghua Yu [Thu, 19 Jul 2007 08:48:13 +0000 (01:48 -0700)]
use the new percpu interface for shared data

Currently most of the per cpu data, which is accessed by different cpus,
has a ____cacheline_aligned_in_smp attribute.  Move all this data to the
new per cpu shared data section: .data.percpu.shared_aligned.

This will seperate the percpu data which is referenced frequently by other
cpus from the local only percpu data.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agodefine new percpu interface for shared data
Fenghua Yu [Thu, 19 Jul 2007 08:48:12 +0000 (01:48 -0700)]
define new percpu interface for shared data

per cpu data section contains two types of data.  One set which is
exclusively accessed by the local cpu and the other set which is per cpu,
but also shared by remote cpus.  In the current kernel, these two sets are
not clearely separated out.  This can potentially cause the same data
cacheline shared between the two sets of data, which will result in
unnecessary bouncing of the cacheline between cpus.

One way to fix the problem is to cacheline align the remotely accessed per
cpu data, both at the beginning and at the end.  Because of the padding at
both ends, this will likely cause some memory wastage and also the
interface to achieve this is not clean.

This patch:

Moves the remotely accessed per cpu data (which is currently marked
as ____cacheline_aligned_in_smp) into a different section, where all the data
elements are cacheline aligned. And as such, this differentiates the local
only data and remotely accessed data cleanly.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: <linux-arch@vger.kernel.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agojprobes: make jprobes a little safer for users
Michael Ellerman [Thu, 19 Jul 2007 08:48:11 +0000 (01:48 -0700)]
jprobes: make jprobes a little safer for users

I realise jprobes are a razor-blades-included type of interface, but that
doesn't mean we can't try and make them safer to use.  This guy I know once
wrote code like this:

struct jprobe jp = { .kp.symbol_name = "foo", .entry = "jprobe_foo" };

And then his kernel exploded. Oops.

This patch adds an arch hook, arch_deref_entry_point() (I don't like it
either) which takes the void * in a struct jprobe, and gives back the text
address that it represents.

We can then use that in register_jprobe() to check that the entry point we're
passed is actually in the kernel text, rather than just some random value.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agojprobes: remove JPROBE_ENTRY()
Michael Ellerman [Thu, 19 Jul 2007 08:48:10 +0000 (01:48 -0700)]
jprobes: remove JPROBE_ENTRY()

AFAICT now that jprobe.entry is a void *, JPROBE_ENTRY doesn't do anything
useful - so remove it ..

I've left a do-nothing version so that out-of-tree jprobes code will still
compile without modifications.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agojprobes: make struct jprobe.entry a void *
Michael Ellerman [Thu, 19 Jul 2007 08:48:09 +0000 (01:48 -0700)]
jprobes: make struct jprobe.entry a void *

Currently jprobe.entry is a kprobe_opcode_t *, but that's a lie.  On some
platforms it doesn't point to an opcode at all, it points to a function
descriptor.

It's really a pointer to something that the arch code can turn into a function
entry point.  And that's what actually happens, none of the generic code ever
looks at jprobe.entry, it's only ever dereferenced by arch code.

So just make it a void *.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoreadahead: sanify file_ra_state names
Fengguang Wu [Thu, 19 Jul 2007 08:48:08 +0000 (01:48 -0700)]
readahead: sanify file_ra_state names

Rename some file_ra_state variables and remove some accessors.

It results in much simpler code.
Kudos to Rusty!

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoreadahead: split ondemand readahead interface into two functions
Rusty Russell [Thu, 19 Jul 2007 08:48:08 +0000 (01:48 -0700)]
readahead: split ondemand readahead interface into two functions

Split ondemand readahead interface into two functions.  I think this makes it
a little clearer for non-readahead experts (like Rusty).

Internally they both call ondemand_readahead(), but the page argument is
changed to an obvious boolean flag.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agomm: share PG_readahead and PG_reclaim
Fengguang Wu [Thu, 19 Jul 2007 08:48:07 +0000 (01:48 -0700)]
mm: share PG_readahead and PG_reclaim

Share the same page flag bit for PG_readahead and PG_reclaim.

One is used only on file reads, another is only for emergency writes.  One
is used mostly for fresh/young pages, another is for old pages.

Combinations of possible interactions are:

a) clear PG_reclaim => implicit clear of PG_readahead
it will delay an asynchronous readahead into a synchronous one
it actually does _good_ for readahead:
the pages will be reclaimed soon, it's readahead thrashing!
in this case, synchronous readahead makes more sense.

b) clear PG_readahead => implicit clear of PG_reclaim
one(and only one) page will not be reclaimed in time
it can be avoided by checking PageWriteback(page) in readahead first

c) set PG_reclaim => implicit set of PG_readahead
will confuse readahead and make it restart the size rampup process
it's a trivial problem, and can mostly be avoided by checking
PageWriteback(page) first in readahead

d) set PG_readahead => implicit set of PG_reclaim
PG_readahead will never be set on already cached pages.
PG_reclaim will always be cleared on dirtying a page.
so not a problem.

In summary,
a)   we get better behavior
b,d) possible interactions can be avoided
c)   racy condition exists that might affect readahead, but the chance
     is _really_ low, and the hurt on readahead is trivial.

Compound pages also use PG_reclaim, but for now they do not interact with
reclaim/readahead code.

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoreadahead: pass real splice size
Fengguang Wu [Thu, 19 Jul 2007 08:48:06 +0000 (01:48 -0700)]
readahead: pass real splice size

Pass real splice size to page_cache_readahead_ondemand().

The splice code works in chunks of 16 pages internally.  The readahead code
should be told of the overall splice size, instead of the internal chunk size.
 Otherwize bad things may happen.  Imagine some 17-page random splice reads.
The code before this patch will result in two readahead calls: readahead(16);
readahead(1); That leads to one 16-page I/O and one 32-page I/O: one extra I/O
and 31 readahead miss pages.

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoreadahead: move synchronous readahead call out of splice loop
Fengguang Wu [Thu, 19 Jul 2007 08:48:05 +0000 (01:48 -0700)]
readahead: move synchronous readahead call out of splice loop

Move synchronous page_cache_readahead_ondemand() call out of splice loop.

This avoids one pointless page allocation/insertion in case of non-zero
ra_pages, or many pointless readahead calls in case of zero ra_pages.

Note that if a user sets ra_pages to less than PIPE_BUFFERS=16 pages, he will
not get expected readahead behavior anyway.  The splice code works in batches
of 16 pages, which can be taken as another form of synchronous readahead.

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoreadahead: remove the old algorithm
Fengguang Wu [Thu, 19 Jul 2007 08:48:04 +0000 (01:48 -0700)]
readahead: remove the old algorithm

Remove the old readahead algorithm.

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Steven Pratt <slpratt@austin.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoreadahead: convert ext3/ext4 invocations
Fengguang Wu [Thu, 19 Jul 2007 08:48:04 +0000 (01:48 -0700)]
readahead: convert ext3/ext4 invocations

Convert ext3/ext4 dir reads to use on-demand readahead.

Readahead for dirs operates _not_ on file level, but on blockdev level.  This
makes a difference when the data blocks are not continuous.  And the read
routine is somehow opaque: there's no handy info about the status of current
page.  So a simplified call scheme is employed: to call into readahead
whenever the current page falls out of readahead windows.

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Steven Pratt <slpratt@austin.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoreadahead: convert splice invocations
Fengguang Wu [Thu, 19 Jul 2007 08:48:03 +0000 (01:48 -0700)]
readahead: convert splice invocations

Convert splice reads to use on-demand readahead.

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Steven Pratt <slpratt@austin.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Jens Axboe <axboe@suse.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoreadahead: convert filemap invocations
Fengguang Wu [Thu, 19 Jul 2007 08:48:02 +0000 (01:48 -0700)]
readahead: convert filemap invocations

Convert filemap reads to use on-demand readahead.

The new call scheme is to
- call readahead on non-cached page
- call readahead on look-ahead page
- update prev_index when finished with the read request

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Steven Pratt <slpratt@austin.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoreadahead: on-demand readahead logic
Fengguang Wu [Thu, 19 Jul 2007 08:48:01 +0000 (01:48 -0700)]
readahead: on-demand readahead logic

This is a minimal readahead algorithm that aims to replace the current one.
It is more flexible and reliable, while maintaining almost the same behavior
and performance.  Also it is full integrated with adaptive readahead.

It is designed to be called on demand:
- on a missing page, to do synchronous readahead
- on a lookahead page, to do asynchronous readahead

In this way it eliminated the awkward workarounds for cache hit/miss,
readahead thrashing, retried read, and unaligned read.  It also adopts the
data structure introduced by adaptive readahead, parameterizes readahead
pipelining with `lookahead_index', and reduces the current/ahead windows to
one single window.

HEURISTICS

The logic deals with four cases:

- sequential-next
found a consistent readahead window, so push it forward

- random
standalone small read, so read as is

- sequential-first
create a new readahead window for a sequential/oversize request

- lookahead-clueless
hit a lookahead page not associated with the readahead window,
so create a new readahead window and ramp it up

In each case, three parameters are determined:

- readahead index: where the next readahead begins
- readahead size:  how much to readahead
- lookahead size:  when to do the next readahead (for pipelining)

BEHAVIORS

The old behaviors are maximally preserved for trivial sequential/random reads.
Notable changes are:

- It no longer imposes strict sequential checks.
  It might help some interleaved cases, and clustered random reads.
  It does introduce risks of a random lookahead hit triggering an
  unexpected readahead. But in general it is more likely to do good
  than to do evil.

- Interleaved reads are supported in a minimal way.
  Their chances of being detected and proper handled are still low.

- Readahead thrashings are better handled.
  The current readahead leads to tiny average I/O sizes, because it
  never turn back for the thrashed pages.  They have to be fault in
  by do_generic_mapping_read() one by one.  Whereas the on-demand
  readahead will redo readahead for them.

OVERHEADS

The new code reduced the overheads of

- excessively calling the readahead routine on small sized reads
  (the current readahead code insists on seeing all requests)

- doing a lot of pointless page-cache lookups for small cached files
  (the current readahead only turns itself off after 256 cache hits,
  unfortunately most files are < 1MB, so never see that chance)

That accounts for speedup of
- 0.3% on 1-page sequential reads on sparse file
- 1.2% on 1-page cache hot sequential reads
- 3.2% on 256-page cache hot sequential reads
- 1.3% on cache hot `tar /lib`

However, it does introduce one extra page-cache lookup per cache miss, which
impacts random reads slightly. That's 1% overheads for 1-page random reads on
sparse file.

PERFORMANCE

The basic benchmark setup is
- 2.6.20 kernel with on-demand readahead
- 1MB max readahead size
- 2.9GHz Intel Core 2 CPU
- 2GB memory
- 160G/8M Hitachi SATA II 7200 RPM disk

The benchmarks show that
- it maintains the same performance for trivial sequential/random reads
- sysbench/OLTP performance on MySQL gains up to 8%
- performance on readahead thrashing gains up to 3 times

iozone throughput (KB/s): roughly the same
==========================================
iozone -c -t1 -s 4096m -r 64k

       2.6.20          on-demand      gain
first run
  "  Initial write "   61437.27        64521.53      +5.0%
  "        Rewrite "   47893.02        48335.20      +0.9%
  "           Read "   62111.84        62141.49      +0.0%
  "        Re-read "   62242.66        62193.17      -0.1%
  "   Reverse Read "   50031.46        49989.79      -0.1%
  "    Stride read "    8657.61         8652.81      -0.1%
  "    Random read "   13914.28        13898.23      -0.1%
  " Mixed workload "   19069.27        19033.32      -0.2%
  "   Random write "   14849.80        14104.38      -5.0%
  "         Pwrite "   62955.30        65701.57      +4.4%
  "          Pread "   62209.99        62256.26      +0.1%

second run
  "  Initial write "   60810.31        66258.69      +9.0%
  "        Rewrite "   49373.89        57833.66     +17.1%
  "           Read "   62059.39        62251.28      +0.3%
  "        Re-read "   62264.32        62256.82      -0.0%
  "   Reverse Read "   49970.96        50565.72      +1.2%
  "    Stride read "    8654.81         8638.45      -0.2%
  "    Random read "   13901.44        13949.91      +0.3%
  " Mixed workload "   19041.32        19092.04      +0.3%
  "   Random write "   14019.99        14161.72      +1.0%
  "         Pwrite "   64121.67        68224.17      +6.4%
  "          Pread "   62225.08        62274.28      +0.1%

In summary, writes are unstable, reads are pretty close on average:

  access pattern  2.6.20  on-demand   gain
   Read  62085.61  62196.38  +0.2%
Re-read  62253.49  62224.99  -0.0%
   Reverse Read  50001.21  50277.75  +0.6%
    Stride read   8656.21   8645.63  -0.1%
    Random read  13907.86  13924.07  +0.1%
   Mixed workload  19055.29  19062.68  +0.0%
  Pread  62217.53  62265.27  +0.1%

aio-stress: roughly the same
============================
aio-stress -l -s4096 -r128 -t1 -o1 knoppix511-dvd-cn.iso
aio-stress -l -s4096 -r128 -t1 -o3 knoppix511-dvd-cn.iso

2.6.20      on-demand  delta
sequential  92.57s      92.54s    -0.0%
random 311.87s     312.15s    +0.1%

sysbench fileio: roughly the same
=================================
sysbench --test=fileio --file-io-mode=async --file-test-mode=rndrw \
 --file-total-size=4G --file-block-size=64K \
 --num-threads=001 --max-requests=10000 --max-time=900 run

threads    2.6.20   on-demand    delta
first run
      1   59.1974s    59.2262s  +0.0%
      2   58.0575s    58.2269s  +0.3%
      4   48.0545s    47.1164s  -2.0%
      8   41.0684s    41.2229s  +0.4%
     16   35.8817s    36.4448s  +1.6%
     32   32.6614s    32.8240s  +0.5%
     64   23.7601s    24.1481s  +1.6%
    128   24.3719s    23.8225s  -2.3%
    256   23.2366s    22.0488s  -5.1%

second run
      1   59.6720s    59.5671s  -0.2%
      8   41.5158s    41.9541s  +1.1%
     64   25.0200s    23.9634s  -4.2%
    256   22.5491s    20.9486s  -7.1%

Note that the numbers are not very stable because of the writes.
The overall performance is close when we sum all seconds up:

                sum all up               495.046s    491.514s   -0.7%

sysbench oltp (trans/sec): up to 8% gain
========================================
sysbench --test=oltp --oltp-table-size=10000000 --oltp-read-only \
 --mysql-socket=/var/run/mysqld/mysqld.sock \
 --mysql-user=root --mysql-password=readahead \
 --num-threads=064 --max-requests=10000 --max-time=900 run

10000-transactions run
threads    2.6.20   on-demand    gain
      1     62.81       64.56   +2.8%
      2     67.97       70.93   +4.4%
      4     81.81       85.87   +5.0%
      8     94.60       97.89   +3.5%
     16     99.07      104.68   +5.7%
     32     95.93      104.28   +8.7%
     64     96.48      103.68   +7.5%
5000-transactions run
      1     48.21       48.65   +0.9%
      8     68.60       70.19   +2.3%
     64     70.57       74.72   +5.9%
2000-transactions run
      1     37.57       38.04   +1.3%
      2     38.43       38.99   +1.5%
      4     45.39       46.45   +2.3%
      8     51.64       52.36   +1.4%
     16     54.39       55.18   +1.5%
     32     52.13       54.49   +4.5%
     64     54.13       54.61   +0.9%

That's interesting results. Some investigations show that
- MySQL is accessing the db file non-uniformly: some parts are
  more hot than others
- It is mostly doing 4-page random reads, and sometimes doing two
  reads in a row, the latter one triggers a 16-page readahead.
- The on-demand readahead leaves many lookahead pages (flagged
  PG_readahead) there. Many of them will be hit, and trigger
  more readahead pages. Which might save more seeks.
- Naturally, the readahead windows tend to lie in hot areas,
  and the lookahead pages in hot areas is more likely to be hit.
- The more overall read density, the more possible gain.

That also explains the adaptive readahead tricks for clustered random reads.

readahead thrashing: 3 times better
===================================
We boot kernel with "mem=128m single", and start a 100KB/s stream on every
second, until reaching 200 streams.

      max throughput     min avg I/O size
2.6.20:            5MB/s               16KB
on-demand:        15MB/s              140KB

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Steven Pratt <slpratt@austin.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoreadahead: data structure and routines
Fengguang Wu [Thu, 19 Jul 2007 08:47:59 +0000 (01:47 -0700)]
readahead: data structure and routines

Extend struct file_ra_state to support the on-demand readahead logic.  Also
define some helpers for it.

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Steven Pratt <slpratt@austin.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoreadahead: MIN_RA_PAGES/MAX_RA_PAGES macros
Fengguang Wu [Thu, 19 Jul 2007 08:47:58 +0000 (01:47 -0700)]
readahead: MIN_RA_PAGES/MAX_RA_PAGES macros

Define two convenient macros for read-ahead:
- MAX_RA_PAGES: rounded down counterpart of VM_MAX_READAHEAD
- MIN_RA_PAGES: rounded _up_ counterpart of VM_MIN_READAHEAD

Note that the rounded up MIN_RA_PAGES will work flawlessly with _large_
page sizes like 64k.

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Steven Pratt <slpratt@austin.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoreadahead: add look-ahead support to __do_page_cache_readahead()
Fengguang Wu [Thu, 19 Jul 2007 08:47:57 +0000 (01:47 -0700)]
readahead: add look-ahead support to __do_page_cache_readahead()

Add look-ahead support to __do_page_cache_readahead().

It works by
- mark the Nth backwards page with PG_readahead,
(which instructs the page's first reader to invoke readahead)
- and only do the marking for newly allocated pages.
(to prevent blindly doing readahead on already cached pages)

Look-ahead is a technique to achieve I/O pipelining:

While the application is working through a chunk of cached pages, the kernel
reads-ahead the next chunk of pages _before_ time of need.  It effectively
hides low level I/O latencies to high level applications.

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Steven Pratt <slpratt@austin.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoreadahead: introduce PG_readahead
Fengguang Wu [Thu, 19 Jul 2007 08:47:55 +0000 (01:47 -0700)]
readahead: introduce PG_readahead

Introduce a new page flag: PG_readahead.

It acts as a look-ahead mark, which tells the page reader: Hey, it's time to
invoke the read-ahead logic.  For the sake of I/O pipelining, don't wait until
it runs out of cached pages!

Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Steven Pratt <slpratt@austin.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoAIO sparse fix (type of ki_flags)
David Brownell [Thu, 19 Jul 2007 08:47:55 +0000 (01:47 -0700)]
AIO sparse fix (type of ki_flags)

Fix type issue reported by latest 'sparse': kiocb.ki_flags should be
"unsigned long" (not "long"), to match bitop type signature.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoeCryptfs: ecryptfs_setattr() bugfix
Michael Halcrow [Thu, 19 Jul 2007 08:47:54 +0000 (01:47 -0700)]
eCryptfs: ecryptfs_setattr() bugfix

There is another bug recently introduced into the ecryptfs_setattr()
function in 2.6.22.  eCryptfs will attempt to treat special files like
regular eCryptfs files on chmod, chown, and so forth.  This leads to a NULL
pointer dereference.  This patch validates that the file is a regular file
before proceeding with operations related to the inode's crypt_stat.

Thanks to Ryusuke Konishi for finding this bug and suggesting the fix.

Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agombcs: Remove lots of global symbols
Alan Cox [Thu, 19 Jul 2007 08:47:53 +0000 (01:47 -0700)]
mbcs: Remove lots of global symbols

MBCS has a collection of things that searches say are not used elsewhere
and could be static.  If this is the case they should be static, if not
then someone at SGI should rename things like "soft_list" so they don't
pollute the global namespace with generic names...

Signed-off-by: Alan Cox <alan@redhat.com>
Acked-by: Bruce Losure <blosure@sgi.com>
Cc: Jes Sorensen <jes@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoAvoid too many remote cpu references due to /proc/stat
Ravikiran G Thirumalai [Thu, 19 Jul 2007 08:47:53 +0000 (01:47 -0700)]
Avoid too many remote cpu references due to /proc/stat

Optimize show_stat to collect per-irq information just once.

On x86_64, with newer kernel versions, kstat_irqs is a bit of a problem.
On every call to kstat_irqs, the process brings in per-cpu data from all
online cpus.  Doing this for NR_IRQS, which is now 256 + 32 * NR_CPUS
results in (256+32*63) * 63 remote cpu references on a 64 cpu config.
Considering the fact that we already compute this value per-cpu, we can
save on the remote references as below.

Signed-off-by: Alok N Kataria <alok.kataria@calsoftinc.com>
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agogpio calls don't need i/o barriers
David Brownell [Thu, 19 Jul 2007 08:47:52 +0000 (01:47 -0700)]
gpio calls don't need i/o barriers

Clarify that drivers using the GPIO operations don't need to issue io
barrier instructions themselves.  Previously this wasn't clear, and at
least one platform assumed otherwise (and would thus break various
otherwise-portable drivers which don't issue barriers).

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agounregister_chrdev() return void
Akinobu Mita [Thu, 19 Jul 2007 08:47:51 +0000 (01:47 -0700)]
unregister_chrdev() return void

unregister_chrdev() does not return meaningful value.  This patch makes it
return void like most unregister_* functions.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agounregister_chrdev(): ignore the return value
Akinobu Mita [Thu, 19 Jul 2007 08:47:50 +0000 (01:47 -0700)]
unregister_chrdev(): ignore the return value

unregister_chrdev() always returns 0.  There is no need to check the return
value.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoUDF: coding style conversion - lindent
Cyrill Gorcunov [Thu, 19 Jul 2007 08:47:43 +0000 (01:47 -0700)]
UDF: coding style conversion - lindent

This patch converts UDF coding style to kernel coding style using Lindent.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Jan Kara <jack@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoSuspend MAINTAINERS update
Pavel Machek [Thu, 19 Jul 2007 08:47:42 +0000 (01:47 -0700)]
Suspend MAINTAINERS update

I guess it is time to clarify that suspend and hibernation are separate
things, and add Rafael as a maintainer.  Plus, people blame us for suspend
problems, anyway, I guess it is fair to mark us as suspend maintainers,
too.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoPM: Integrate beeping flag with existing acpi_sleep flags
Pavel Machek [Thu, 19 Jul 2007 08:47:41 +0000 (01:47 -0700)]
PM: Integrate beeping flag with existing acpi_sleep flags

Move "debug during resume from s2ram" into the variable we already use
for real-mode flags to simplify code. It also closes nasty trap for
the user in acpi_sleep_setup; order of parameters actually mattered there,
acpi_sleep=s3_bios,s3_mode doing something different from
acpi_sleep=s3_mode,s3_bios.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoPM: Optional beeping during resume from suspend to RAM
Nigel Cunningham [Thu, 19 Jul 2007 08:47:41 +0000 (01:47 -0700)]
PM: Optional beeping during resume from suspend to RAM

Add a feature allowing the user to make the system beep during a resume from
suspend to RAM, on x86_64 and i386.

This is useful for the users with broken resume from RAM, so that they can
verify if the control reaches the kernel after a wake-up event.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoPM: Introduce pm_power_off_prepare
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:40 +0000 (01:47 -0700)]
PM: Introduce pm_power_off_prepare

Introduce the pm_power_off_prepare() callback that can be registered by the
interested platforms in analogy with pm_idle() and pm_power_off(), used for
preparing the system to power off (needed by ACPI).

This allows us to drop acpi_sysclass and device_acpi that are only defined in
order to register the ACPI power off preparation callback, which is needed by
pm_power_off() registered in a much different way.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoACPI: Do not prepare for hibernation in acpi_shutdown
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:39 +0000 (01:47 -0700)]
ACPI: Do not prepare for hibernation in acpi_shutdown

Since we are now explicitly calling hibernation_ops->prepare() before
hibernation_ops->enter() in hibernation_platform_enter() (defined in
kernel/power/disk.c), ACPI should not call acpi_sleep_prepare(ACPI_STATE_S4)
from acpi_shutdown().

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoPM: Reduce code duplication between main.c and user.c
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:38 +0000 (01:47 -0700)]
PM: Reduce code duplication between main.c and user.c

The SNAPSHOT_S2RAM ioctl code is outdated and it should not duplicate the
suspend code in kernel/power/main.c.  Fix that.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoPM: prevent frozen user mode helpers from failing the freezing of tasks
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:37 +0000 (01:47 -0700)]
PM: prevent frozen user mode helpers from failing the freezing of tasks

At present, if a user mode helper is running while
usermodehelper_pm_callback() is executed, the helper may be frozen and the
completion in call_usermodehelper_exec() won't be completed until user
space processes are thawed.  As a result, the freezing of kernel threads
may fail, which is not desirable.

Prevent this from happening by introducing a counter of running user mode
helpers and allowing usermodehelper_pm_callback() to succeed for action =
PM_HIBERNATION_PREPARE or action = PM_SUSPEND_PREPARE only if there are no
helpers running.  [Namely, usermodehelper_pm_callback() waits for at most
RUNNING_HELPERS_TIMEOUT for the number of running helpers to become zero
and fails if that doesn't happen.]

Special thanks to Uli Luckas <u.luckas@road.de>, Pavel Machek
<pavel@ucw.cz> and Oleg Nesterov <oleg@tv-sign.ru> for reviewing the
previous versions of this patch and for very useful comments.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Uli Luckas <u.luckas@road.de>
Acked-by: Nigel Cunningham <nigel@nigel.suspend2.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoPM: disable usermode helper before hibernation and suspend
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:36 +0000 (01:47 -0700)]
PM: disable usermode helper before hibernation and suspend

Use a hibernation and suspend notifier to disable the user mode helper before
a hibernation/suspend and enable it after the operation.

[akpm@linux-foundation.org: build fix]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoPM: introduce hibernation and suspend notifiers
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:36 +0000 (01:47 -0700)]
PM: introduce hibernation and suspend notifiers

Make it possible to register hibernation and suspend notifiers, so that
subsystems can perform hibernation-related or suspend-related operations that
should not be carried out by device drivers' .suspend() and .resume()
routines.

[akpm@linux-foundation.org: build fixes]
[akpm@linux-foundation.org: cleanups]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoFreezer: remove redundant check in try_to_freeze_tasks
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:35 +0000 (01:47 -0700)]
Freezer: remove redundant check in try_to_freeze_tasks

We don't need to check if todo is positive before calling time_after() in
try_to_freeze_tasks(), because if todo is zero at this point, the loop will be
broken anyway due to the while () condition being false.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoFreezer: return int from freeze_processes
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:34 +0000 (01:47 -0700)]
Freezer: return int from freeze_processes

Make try_to_freeze_tasks() and freeze_processes() return -EBUSY on failure
instead of the number of unfrozen tasks (none of the callers actually uses
this number).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoFreezer: use __set_current_state in refrigerator
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:33 +0000 (01:47 -0700)]
Freezer: use __set_current_state in refrigerator

Use __set_current_state() as appropriate in refrigerator() instead of
accessing current->state directly.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoFreezer: avoid freezing kernel threads prematurely
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:33 +0000 (01:47 -0700)]
Freezer: avoid freezing kernel threads prematurely

Kernel threads should not have TIF_FREEZE set when user space processes are
being frozen, since otherwise some of them might be frozen prematurely.
To prevent this from happening we can (1) make exit_mm() unset TIF_FREEZE
unconditionally just after clearing tsk->mm and (2) make try_to_freeze_tasks()
check if p->mm is different from zero and PF_BORROWED_MM is unset in p->flags
when user space processes are to be frozen.

Namely, when user space processes are being frozen, we only should set
TIF_FREEZE for tasks that have p->mm different from NULL and don't have
PF_BORROWED_MM set in p->flags.  For this reason task_lock() must be used to
prevent try_to_freeze_tasks() from racing with use_mm()/unuse_mm(), in which
p->mm and p->flags.PF_BORROWED_MM are changed under task_lock(p).  Also, we
need to prevent the following scenario from happening:

* daemonize() is called by a task spawned from a user space code path
* freezer checks if the task has p->mm set and the result is positive
* task enters exit_mm() and clears its TIF_FREEZE
* freezer sets TIF_FREEZE for the task
* task calls try_to_freeze() and goes to the refrigerator, which is wrong at
  that point

This requires us to acquire task_lock(p) before p->flags.PF_BORROWED_MM and
p->mm are examined and release it after TIF_FREEZE is set for p (or it turns
out that TIF_FREEZE should not be set).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoHibernation: prepare to enter the low power state
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:31 +0000 (01:47 -0700)]
Hibernation: prepare to enter the low power state

During hibernation we call hibernation_ops->prepare() before creating the image,
but then, before saving it, we cancel the power transition by calling
hibernation_ops->finish().  Thus prior to calling hibernation_ops->enter() we
should let the platform firmware know that we're going to enter the low power
state after all.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoswsusp: fix hibernation code ordering
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:31 +0000 (01:47 -0700)]
swsusp: fix hibernation code ordering

Change the code ordering so that hibernation_ops->prepare() is called after
device_suspend().  This is needed so that we don't violate the ACPI
specification, which states that the _PTS and _GTS system-control methods,
executed from acpi_sleep_prepare(), ought to be called after devices have been
put in low power states.

The "Finish" label in hibernation_restore() is moved, because device_suspend()
resumes devices if the suspending of them fails and the restore code ordering
should reflect the hibernation code ordering.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoswsusp: introduce restore platform operations
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:30 +0000 (01:47 -0700)]
swsusp: introduce restore platform operations

At least on some machines it is necessary to prepare the ACPI firmware for the
restoration of the system memory state from the hibernation image if the
"platform" mode of hibernation has been used.  Namely, in that cases we need
to disable the GPEs before replacing the "boot" kernel with the "frozen"
kernel (cf.  http://bugzilla.kernel.org/show_bug.cgi?id=7887).  After the
restore they will be re-enabled by hibernation_ops->finish(), but if the
restore fails, they have to be re-enabled by the restore code explicitly.

For this purpose we can introduce two additional hibernation operations,
called pre_restore() and restore_cleanup() and call them from the restore code
path.  Still, they should be called if the "platform" mode of hibernation has
been used, so we need to pass the information about the hibernation mode from
the "frozen" kernel to the "boot" kernel in the image header.

Apparently, we can't drop the disabling of GPEs before the restore because of
Bug #7887 .  Â We also can't do it unconditionally, because the GPEs wouldn't
have been enabled after a successful restore if the suspend had been done in
the 'shutdown' or 'reboot' mode.

In principle we could (and probably should) unconditionally disable the GPEs
before each snapshot creation *and* before the restore, but then we'd have to
unconditionally enable them after the snapshot creation as well as after the
restore (or restore failure) Â  Still, for this purpose we'd need to modify
acpi_enter_sleep_state_prep() and acpi_leave_sleep_state() and we'd have to
introduce some mechanism synchronizing the disablind/enabling of the GPEs with
the device drivers' .suspend()/.resume() routines and with
disable_/enable_nonboot_cpus().  Â However, this would have affected the
suspend (ie.  s2ram) code as well as the hibernation, which I'd like to avoid
in this patch series.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoswsusp: remove code duplication between disk.c and user.c
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:29 +0000 (01:47 -0700)]
swsusp: remove code duplication between disk.c and user.c

Currently, much of the code in kernel/power/disk.c is duplicated in
kernel/power/user.c , mainly for historical reasons.  By eliminating this code
duplication we can reduce the size of user.c quite substantially and remove
the maintenance difficulty resulting from it.

[bunk@stusta.de: kernel/power/disk.c: make code static]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoswsusp: remove incorrect code from user.c
Rafael J. Wysocki [Thu, 19 Jul 2007 08:47:28 +0000 (01:47 -0700)]
swsusp: remove incorrect code from user.c

In the face of the recent change of suspend code ordering (cf.
http://marc.info/?l=linux-acpi&m=117938245931603&w=2) we should also modify
the code ordering in swsusp so that hibernation_ops->prepare() is executed
after device_suspend().

However, for this purpose it seems reasonable to eliminate the code
duplication between kernel/power/disk.c and kernel/power/user.c first.  By
eliminating it we can reduce the size of user.c quite substantially and remove
the maintenance difficulty with making essentially the same changes in two
different places.

Moreover, we should also remove the calls to "platform" functions from the
restore code path, since it doesn't carry out any power transition of the
system, but we generally need to disable the GPEs before the restore if the
'platform' hibernation mode has been used.  To do this, we can introduce two
new hibernation_ops to be used in the restore code.

This patch:

Make the code hibernation code in kernel/power/user.c be functionally
equivalent to the corresponding code in kernel/power/disk.c , as it should be.

The calls to the platform functions removed by this patch are incorrect.  They
should be replaced with some other "platform" invocations that will be
introduced in one of the subsequent patches.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoPM: Do not require dev spew to get PM_DEBUG
Ben Collins [Thu, 19 Jul 2007 08:47:27 +0000 (01:47 -0700)]
PM: Do not require dev spew to get PM_DEBUG

In order to enable things like PM_TRACE, you're required to enable
PM_DEBUG, which sends a large spew of messages on boot, and often times can
overflow dmesg buffer.

Create new PM_VERBOSE and shift that to be the option that enables
drivers/base/power's messages.

Signed-off-by: Ben Collins <bcollins@ubuntu.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agofreezer: run show_state() when freezing times out
Andrew Morton [Thu, 19 Jul 2007 08:47:26 +0000 (01:47 -0700)]
freezer: run show_state() when freezing times out

To see which tasks are stuck where.

Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoonly allow nonlinear vmas for ram backed filesystems
Miklos Szeredi [Thu, 19 Jul 2007 08:47:24 +0000 (01:47 -0700)]
only allow nonlinear vmas for ram backed filesystems

page_mkclean() doesn't re-protect ptes for non-linear mappings, so a later
re-dirty through such a mapping will not generate a fault, PG_dirty will
not reflect the dirty state and the dirty count will be skewed.  This
implies that msync() is also currently broken for nonlinear mappings.

The easiest solution is to emulate remap_file_pages on non-linear mappings
with simple mmap() for non ram-backed filesystems.  Applications continue
to work (albeit slower), as long as the number of remappings remain below
the maximum vma count.

However all currently known real uses of non-linear mappings are for ram
backed filesystems, which this patch doesn't affect.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoRemove alloc_zeroed_user_highpage()
Mel Gorman [Thu, 19 Jul 2007 08:47:23 +0000 (01:47 -0700)]
Remove alloc_zeroed_user_highpage()

alloc_zeroed_user_highpage() has no in-tree users and it is not exported.
As it is not exported, it can simply be removed.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agomm: fix clear_page_dirty_for_io vs fault race
Nick Piggin [Thu, 19 Jul 2007 08:47:22 +0000 (01:47 -0700)]
mm: fix clear_page_dirty_for_io vs fault race

Fix msync data loss and (less importantly) dirty page accounting
inaccuracies due to the race remaining in clear_page_dirty_for_io().

The deleted comment explains what the race was, and the added comments
explain how it is fixed.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agomm: fault feedback #2
Nick Piggin [Thu, 19 Jul 2007 08:47:05 +0000 (01:47 -0700)]
mm: fault feedback #2

This patch completes Linus's wish that the fault return codes be made into
bit flags, which I agree makes everything nicer.  This requires requires
all handle_mm_fault callers to be modified (possibly the modifications
should go further and do things like fault accounting in handle_mm_fault --
however that would be for another patch).

[akpm@linux-foundation.org: fix alpha build]
[akpm@linux-foundation.org: fix s390 build]
[akpm@linux-foundation.org: fix sparc build]
[akpm@linux-foundation.org: fix sparc64 build]
[akpm@linux-foundation.org: fix ia64 build]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
Cc: Bryan Wu <bryan.wu@analog.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
Cc: Richard Curnow <rc@rc0.org.uk>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
Cc: Chris Zankel <chris@zankel.net>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Still apparently needs some ARM and PPC loving - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agomm: fault feedback #1
Nick Piggin [Thu, 19 Jul 2007 08:47:03 +0000 (01:47 -0700)]
mm: fault feedback #1

Change ->fault prototype.  We now return an int, which contains
VM_FAULT_xxx code in the low byte, and FAULT_RET_xxx code in the next byte.
 FAULT_RET_ code tells the VM whether a page was found, whether it has been
locked, and potentially other things.  This is not quite the way he wanted
it yet, but that's changed in the next patch (which requires changes to
arch code).

This means we no longer set VM_CAN_INVALIDATE in the vma in order to say
that a page is locked which requires filemap_nopage to go away (because we
can no longer remain backward compatible without that flag), but we were
going to do that anyway.

struct fault_data is renamed to struct vm_fault as Linus asked. address
is now a void __user * that we should firmly encourage drivers not to use
without really good reason.

The page is now returned via a page pointer in the vm_fault struct.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoDocument ->page_mkwrite() locking
Mark Fasheh [Thu, 19 Jul 2007 08:47:01 +0000 (01:47 -0700)]
Document ->page_mkwrite() locking

There seems to be very little documentation about this callback in general.
The locking in particular is a bit tricky, so it's worth having this in
writing.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoocfs2: release page lock before calling ->page_mkwrite
Mark Fasheh [Thu, 19 Jul 2007 08:47:00 +0000 (01:47 -0700)]
ocfs2: release page lock before calling ->page_mkwrite

__do_fault() was calling ->page_mkwrite() with the page lock held, which
violates the locking rules for that callback.  Release and retake the page
lock around the callback to avoid deadlocking file systems which manually
take it.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agomm: merge populate and nopage into fault (fixes nonlinear)
Nick Piggin [Thu, 19 Jul 2007 08:46:59 +0000 (01:46 -0700)]
mm: merge populate and nopage into fault (fixes nonlinear)

Nonlinear mappings are (AFAIKS) simply a virtual memory concept that encodes
the virtual address -> file offset differently from linear mappings.

->populate is a layering violation because the filesystem/pagecache code
should need to know anything about the virtual memory mapping.  The hitch here
is that the ->nopage handler didn't pass down enough information (ie.  pgoff).
 But it is more logical to pass pgoff rather than have the ->nopage function
calculate it itself anyway (because that's a similar layering violation).

Having the populate handler install the pte itself is likewise a nasty thing
to be doing.

This patch introduces a new fault handler that replaces ->nopage and
->populate and (later) ->nopfn.  Most of the old mechanism is still in place
so there is a lot of duplication and nice cleanups that can be removed if
everyone switches over.

The rationale for doing this in the first place is that nonlinear mappings are
subject to the pagefault vs invalidate/truncate race too, and it seemed stupid
to duplicate the synchronisation logic rather than just consolidate the two.

After this patch, MAP_NONBLOCK no longer sets up ptes for pages present in
pagecache.  Seems like a fringe functionality anyway.

NOPAGE_REFAULT is removed.  This should be implemented with ->fault, and no
users have hit mainline yet.

[akpm@linux-foundation.org: cleanup]
[randy.dunlap@oracle.com: doc. fixes for readahead]
[akpm@linux-foundation.org: build fix]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agomm: fix fault vs invalidate race for linear mappings
Nick Piggin [Thu, 19 Jul 2007 08:46:57 +0000 (01:46 -0700)]
mm: fix fault vs invalidate race for linear mappings

Fix the race between invalidate_inode_pages and do_no_page.

Andrea Arcangeli identified a subtle race between invalidation of pages from
pagecache with userspace mappings, and do_no_page.

The issue is that invalidation has to shoot down all mappings to the page,
before it can be discarded from the pagecache.  Between shooting down ptes to
a particular page, and actually dropping the struct page from the pagecache,
do_no_page from any process might fault on that page and establish a new
mapping to the page just before it gets discarded from the pagecache.

The most common case where such invalidation is used is in file truncation.
This case was catered for by doing a sort of open-coded seqlock between the
file's i_size, and its truncate_count.

Truncation will decrease i_size, then increment truncate_count before
unmapping userspace pages; do_no_page will read truncate_count, then find the
page if it is within i_size, and then check truncate_count under the page
table lock and back out and retry if it had subsequently been changed (ptl
will serialise against unmapping, and ensure a potentially updated
truncate_count is actually visible).

Complexity and documentation issues aside, the locking protocol fails in the
case where we would like to invalidate pagecache inside i_size.  do_no_page
can come in anytime and filemap_nopage is not aware of the invalidation in
progress (as it is when it is outside i_size).  The end result is that
dangling (->mapping == NULL) pages that appear to be from a particular file
may be mapped into userspace with nonsense data.  Valid mappings to the same
place will see a different page.

Andrea implemented two working fixes, one using a real seqlock, another using
a page->flags bit.  He also proposed using the page lock in do_no_page, but
that was initially considered too heavyweight.  However, it is not a global or
per-file lock, and the page cacheline is modified in do_no_page to increment
_count and _mapcount anyway, so a further modification should not be a large
performance hit.  Scalability is not an issue.

This patch implements this latter approach.  ->nopage implementations return
with the page locked if it is possible for their underlying file to be
invalidated (in that case, they must set a special vm_flags bit to indicate
so).  do_no_page only unlocks the page after setting up the mapping
completely.  invalidation is excluded because it holds the page lock during
invalidation of each page (and ensures that the page is not mapped while
holding the lock).

This also allows significant simplifications in do_no_page, because we have
the page locked in the right place in the pagecache from the start.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
17 years agoMerge branch 'isdn-fix' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6
Linus Torvalds [Thu, 19 Jul 2007 01:38:25 +0000 (18:38 -0700)]
Merge branch 'isdn-fix' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6

* 'isdn-fix' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6:
  ISDN HiSax: uninitialized return in hisax_cs_setup

17 years agoMerge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik...
Linus Torvalds [Thu, 19 Jul 2007 01:33:45 +0000 (18:33 -0700)]
Merge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/netdev-2.6

* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/netdev-2.6:
  eHEA: Fix bonding support
  Blackfin ethernet driver: on chip ethernet MAC controller driver
  fix wrong argument of tc35815_read_plat_dev_addr()
  ARM/ETHER3: Handle multicast frames.
  SAA9730: Handle multicast frames.
  NI5010: Handle multicast frames.
  NS83820: Handle multicast frames.
  Fix RGMII-ID handling in gianfar
  Fix Vitesse RGMII-ID support
  Add phy-connection-type to gianfar nodes
  Fix Vitesse 824x PHY interrupt acking
  [PATCH] zd1211rw: Add ID for Siemens Gigaset USB Stick 54
  [PATCH] zd1211rw: Add ID for Planex GW-US54GXS
  [PATCH] Update version ipw2200 stamp to 1.2.2
  [PATCH] ipw2200: Fix ipw_isr() comments error on shared IRQ
  [PATCH] Fix ipw2200 set wrong power parameter causing firmware error
  [PATCH] ipw2100: Fix `iwpriv set_power` error
  [PATCH] softmac: Channel is listed twice in scan output

17 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6
Linus Torvalds [Thu, 19 Jul 2007 01:32:28 +0000 (18:32 -0700)]
Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6: (24 commits)
  [CIFS] merge conflict in fs/cifs/export.c
  [CIFS] Allow disabling CIFS Unix Extensions as mount option
  [CIFS] More whitespace/formatting fixes (noticed by checkpatch)
  [CIFS] Typo in previous patch
  [CIFS] zero_user_page() conversions
  [CIFS] use simple_prepare_write to zero page data
  [CIFS] Fix build break - inet.h not included when experimental ifdef off
  [CIFS] Add support for new POSIX unlink
  [CIFS] whitespace/formatting fixes
  [CIFS] Fix oops in cifs_create when nfsd server exports cifs mount
  [CIFS] whitespace cleanup
  [CIFS] Fix packet signatures for NTLMv2 case
  [CIFS] more whitespace fixes
  [CIFS] more whitespace cleanup
  [CIFS] whitespace cleanup
  [CIFS] whitespace cleanup
  [CIFS] ipv6 support no longer experimental
  [CIFS] Mount should fail if server signing off but client mount option requires it
  [CIFS] whitespace fixes
  [CIFS] Fix sign mount option and sign proc config setting
  ...

17 years agoMerge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/docs-2.6
Linus Torvalds [Thu, 19 Jul 2007 01:28:34 +0000 (18:28 -0700)]
Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/docs-2.6

* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/docs-2.6:
  zh_CN/HOWTO: update URLs of git trees
  Chinese translation of Documentation/stable_api_nonsense.txt
  HOWTO: add Chinese translation of Documentation/HOWTO
  Documentation: add Japanese translated stable_api_nonsense.txt
  HOWTO: add Japanese translation of Documentation/HOWTO

17 years agoMerge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6
Linus Torvalds [Thu, 19 Jul 2007 01:28:08 +0000 (18:28 -0700)]
Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6

* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6:
  sysfs: cosmetic clean up on node creation failure paths
  sysfs: kill an extra put in sysfs_create_link() failure path
  Driver core: check return code of sysfs_create_link()
  HOWTO: Add the knwon_regression URI to the documentation
  dev_vdbg() documentation
  dev_vdbg(), available with -DVERBOSE_DEBUG
  sysfs: make sysfs_init_inode() static
  sysfs: fix sysfs root inode nlink accounting
  Documentation fix devres.txt: lib/iomap.c -> lib/devres.c
  sysfs: avoid kmem_cache_free(NULL)
  PM: remove deprecated dpm_runtime_* routines
  PM: Remove deprecated sysfs files
  Driver core: accept all valid action-strings in uevent-trigger
  debugfs: remove rmdir() non-empty complaint

17 years agoMerge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/uio-2.6
Linus Torvalds [Thu, 19 Jul 2007 01:27:50 +0000 (18:27 -0700)]
Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/uio-2.6

* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/uio-2.6:
  UIO: Hilscher CIF card driver
  UIO: Documentation
  UIO: Add the User IO core code

17 years agoMerge branch 'for-linus' of git://linux-nfs.org/~bfields/linux
Linus Torvalds [Thu, 19 Jul 2007 01:27:00 +0000 (18:27 -0700)]
Merge branch 'for-linus' of git://linux-nfs.org/~bfields/linux

* 'for-linus' of git://linux-nfs.org/~bfields/linux:
  locks: fix vfs_test_lock() comment
  locks: make posix_test_lock() interface more consistent
  nfs: disable leases over NFS
  gfs2: stop giving out non-cluster-coherent leases
  locks: export setlease to filesystems
  locks: provide a file lease method enabling cluster-coherent leases
  locks: rename lease functions to reflect locks.c conventions
  locks: share more common lease code
  locks: clean up lease_alloc()
  locks: convert an -EINVAL return to a BUG
  leases: minor break_lease() comment clarification

17 years agoMerge branch 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband
Linus Torvalds [Thu, 19 Jul 2007 01:26:18 +0000 (18:26 -0700)]
Merge branch 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband

* 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband: (29 commits)
  IB/mthca: Simplify use of size0 in work request posting
  IB/mthca: Factor out setting WQE UD segment entries
  IB/mthca: Factor out setting WQE remote address and atomic segment entries
  IB/mlx4: Factor out setting other WQE segments
  IB/mlx4: Factor out setting WQE data segment entries
  IB/mthca: Factor out setting WQE data segment entries
  IB/mlx4: Return receive queue sizes for userspace QPs from query QP
  IB/mlx4: Increase max outstanding RDMA reads as target
  RDMA/cma: Remove local write permission from QP access flags
  IB/mthca: Use uninitialized_var() for f0
  IB/cm: Make internal function cm_get_ack_delay() static
  IB/ipath: Remove ipath_get_user_pages_nocopy()
  IB/ipath: Make a few functions static
  mlx4_core: Reset device when internal error is detected
  IB/iser: Make a couple of functions static
  IB/mthca: Fix printk format used for firmware version in warning
  IB/mthca: Schedule MSI support for removal
  IB/ehca: Fix warnings issued by checkpatch.pl
  IB/ehca: Restructure ehca_set_pagebuf()
  IB/ehca: MR/MW structure refactoring
  ...

17 years agoMerge branch 'master' of /pub/scm/linux/kernel/git/torvalds/linux-2.6
Steve French [Thu, 19 Jul 2007 00:38:57 +0000 (00:38 +0000)]
Merge branch 'master' of /pub/scm/linux/kernel/git/torvalds/linux-2.6

Conflicts:

fs/cifs/export.c

17 years ago[CIFS] merge conflict in fs/cifs/export.c
Steve French [Thu, 19 Jul 2007 00:32:25 +0000 (00:32 +0000)]
[CIFS] merge conflict in fs/cifs/export.c

Signed-off-by: Steve French <sfrench@us.ibm.com>
17 years ago[CIFS] Allow disabling CIFS Unix Extensions as mount option
Steve French [Wed, 18 Jul 2007 23:21:09 +0000 (23:21 +0000)]
[CIFS] Allow disabling CIFS Unix Extensions as mount option

Previously the only way to do this was to umount all mounts to that server,
turn off a proc setting (/proc/fs/cifs/LinuxExtensionsEnabled).

Fixes Samba bugzilla bug number: 4582 (and also 2008)

Signed-off-by: Steve French <sfrench@us.ibm.com>
17 years agolocks: fix vfs_test_lock() comment
J. Bruce Fields [Fri, 11 May 2007 20:22:50 +0000 (16:22 -0400)]
locks: fix vfs_test_lock() comment

Thanks to Doug Chapman for pointing out that the comment here is
inconsistent with the function prototype.

Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
17 years agolocks: make posix_test_lock() interface more consistent
J. Bruce Fields [Fri, 11 May 2007 20:09:32 +0000 (16:09 -0400)]
locks: make posix_test_lock() interface more consistent

Since posix_test_lock(), like fcntl() and ->lock(), indicates absence or
presence of a conflict lock by setting fl_type to, respectively, F_UNLCK
or something other than F_UNLCK, the return value is no longer needed.

Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
17 years agonfs: disable leases over NFS
J. Bruce Fields [Fri, 8 Jun 2007 19:23:34 +0000 (15:23 -0400)]
nfs: disable leases over NFS

As Peter Staubach says elsewhere
(http://marc.info/?l=linux-kernel&m=118113649526444&w=2):

> The problem is that some file system such as NFSv2 and NFSv3 do
> not have sufficient support to be able to support leases correctly.
> In particular for these two file systems, there is no over the wire
> protocol support.
>
> Currently, these two file systems fail the fcntl(F_SETLEASE) call
> accidentally, due to a reference counting difference.  These file
> systems should fail more consciously, with a proper error to
> indicate that the call is invalid for them.

Define an nfs setlease method that just returns -EINVAL.

If someone can demonstrate a real need, perhaps we could reenable
them in the presence of the "nolock" mount option.

Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Cc: Peter Staubach <staubach@redhat.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
17 years agogfs2: stop giving out non-cluster-coherent leases
Marc Eshel [Mon, 15 Jan 2007 23:33:36 +0000 (18:33 -0500)]
gfs2: stop giving out non-cluster-coherent leases

Since gfs2 can't prevent conflicting opens or leases on other nodes, we
probably shouldn't allow it to give out leases at all.

Put the newly defined lease operation into use in gfs2 by turning off
lease, unless we're using the "nolock' locking module (in which case all
locking is local anyway).

Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Steven Whitehouse <swhiteho@redhat.com>
17 years agolocks: export setlease to filesystems
J. Bruce Fields [Wed, 4 Jul 2007 21:21:37 +0000 (17:21 -0400)]
locks: export setlease to filesystems

Export setlease so it can used by filesystems to implement their lease
methods.

Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
17 years agolocks: provide a file lease method enabling cluster-coherent leases
J. Bruce Fields [Tue, 14 Nov 2006 20:51:40 +0000 (15:51 -0500)]
locks: provide a file lease method enabling cluster-coherent leases

Currently leases are only kept locally, so there's no way for a distributed
filesystem to enforce them against multiple clients.  We're particularly
interested in the case of nfsd exporting a cluster filesystem, in which
case nfsd needs cluster-coherent leases in order to implement delegations
correctly.

Also add some documentation.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
17 years agolocks: rename lease functions to reflect locks.c conventions
J. Bruce Fields [Thu, 7 Jun 2007 21:09:49 +0000 (17:09 -0400)]
locks: rename lease functions to reflect locks.c conventions

We've been using the convention that vfs_foo is the function that calls
a filesystem-specific foo method if it exists, or falls back on a
generic method if it doesn't; thus vfs_foo is what is called when some
other part of the kernel (normally lockd or nfsd) wants to get a lock,
whereas foo is what filesystems call to use the underlying local
functionality as part of their lock implementation.

So rename setlease to vfs_setlease (which will call a
filesystem-specific setlease after a later patch) and __setlease to
setlease.

Also, vfs_setlease need only be GPL-exported as long as it's only needed
by lockd and nfsd.

Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
17 years agolocks: share more common lease code
J. Bruce Fields [Thu, 31 May 2007 21:03:46 +0000 (17:03 -0400)]
locks: share more common lease code

Share more code between setlease (used by nfsd) and fcntl.

Also some minor cleanup.

Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Acked-by: Christoph Hellwig <hch@infradead.org>
17 years agolocks: clean up lease_alloc()
J. Bruce Fields [Thu, 1 Mar 2007 19:34:35 +0000 (14:34 -0500)]
locks: clean up lease_alloc()

Return the newly allocated structure as the return value instead of
using a struct ** parameter.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
17 years agolocks: convert an -EINVAL return to a BUG
J. Bruce Fields [Sat, 30 Jun 2007 16:40:32 +0000 (12:40 -0400)]
locks: convert an -EINVAL return to a BUG

There's no point trying to return an error in these cases, which all represent
bugs in the callers.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
17 years agoleases: minor break_lease() comment clarification
david m. richter [Wed, 9 May 2007 20:10:27 +0000 (16:10 -0400)]
leases: minor break_lease() comment clarification

clarify that break_lease() checks for presence of any lock, not just leases.

Signed-off-by: David M. Richter <richterd@citi.umich.edu>
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
17 years agozh_CN/HOWTO: update URLs of git trees
Li Yang [Tue, 26 Jun 2007 03:15:27 +0000 (11:15 +0800)]
zh_CN/HOWTO: update URLs of git trees

Addressing patch from Stefan Richter:
HOWTO: update URLs of git trees
(It will be better if we update this to commit-id later)

Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
17 years agoChinese translation of Documentation/stable_api_nonsense.txt
TripleX [Thu, 21 Jun 2007 17:20:36 +0000 (01:20 +0800)]
Chinese translation of Documentation/stable_api_nonsense.txt

This is a Chinese translated version of
Documentation/stable_api_nonsense.txt.

From: TripleX <zhongyu@18mail.cn>
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>