Pavel Emelyanov [Fri, 19 Oct 2007 06:39:54 +0000 (23:39 -0700)]
Make access to task's nsproxy lighter
When someone wants to deal with some other taks's namespaces it has to lock
the task and then to get the desired namespace if the one exists. This is
slow on read-only paths and may be impossible in some cases.
E.g. Oleg recently noticed a race between unshare() and the (sent for
review in cgroups) pid namespaces - when the task notifies the parent it
has to know the parent's namespace, but taking the task_lock() is
impossible there - the code is under write locked tasklist lock.
On the other hand switching the namespace on task (daemonize) and releasing
the namespace (after the last task exit) is rather rare operation and we
can sacrifice its speed to solve the issues above.
The access to other task namespaces is proposed to be performed
like this:
rcu_read_lock();
nsproxy = task_nsproxy(tsk);
if (nsproxy != NULL) {
/ *
* work with the namespaces here
* e.g. get the reference on one of them
* /
} / *
* NULL task_nsproxy() means that this task is
* almost dead (zombie)
* /
rcu_read_unlock();
This patch has passed the review by Eric and Oleg :) and,
of course, tested.
[clg@fr.ibm.com: fix unshare()]
[ebiederm@xmission.com: Update get_net_ns_by_pid] Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
pid namespaces: move alloc_pid() to copy_process()
Move alloc_pid() into copy_process(). This will keep all pid and pid
namespace code together and simplify error handling when we support multiple
pid namespaces.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Pavel Emelianov <xemul@openvz.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: Herbert Poetzel <herbert@13thfloor.at> Cc: Kirill Korotaev <dev@sw.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Serge E. Hallyn [Fri, 19 Oct 2007 06:39:52 +0000 (23:39 -0700)]
pid namespaces: define is_global_init() and is_container_init()
is_init() is an ambiguous name for the pid==1 check. Split it into
is_global_init() and is_container_init().
A cgroup init has it's tsk->pid == 1.
A global init also has it's tsk->pid == 1 and it's active pid namespace
is the init_pid_ns. But rather than check the active pid namespace,
compare the task structure with 'init_pid_ns.child_reaper', which is
initialized during boot to the /sbin/init process and never changes.
Changelog:
2.6.22-rc4-mm2-pidns1:
- Use 'init_pid_ns.child_reaper' to determine if a given task is the
global init (/sbin/init) process. This would improve performance
and remove dependence on the task_pid().
2.6.21-mm2-pidns2:
- [Sukadev Bhattiprolu] Changed is_container_init() calls in {powerpc,
ppc,avr32}/traps.c for the _exception() call to is_global_init().
This way, we kill only the cgroup if the cgroup's init has a
bug rather than force a kernel panic.
[akpm@linux-foundation.org: fix comment]
[sukadev@us.ibm.com: Use is_global_init() in arch/m32r/mm/fault.c]
[bunk@stusta.de: kernel/pid.c: remove unused exports]
[sukadev@us.ibm.com: Fix capability.c to work with threaded init] Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Acked-by: Pavel Emelianov <xemul@openvz.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Herbert Poetzel <herbert@13thfloor.at> Cc: Kirill Korotaev <dev@sw.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rename the child_reaper() function to task_child_reaper() to be similar to
other task_* functions and to distinguish the function from 'struct
pid_namspace.child_reaper'.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Pavel Emelianov <xemul@openvz.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: Herbert Poetzel <herbert@13thfloor.at> Cc: Kirill Korotaev <dev@sw.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
pid namespaces: define and use task_active_pid_ns() wrapper
With multiple pid namespaces, a process is known by some pid_t in every
ancestor pid namespace. Every time the process forks, the child process also
gets a pid_t in every ancestor pid namespace.
While a process is visible in >=1 pid namespaces, it can see pid_t's in only
one pid namespace. We call this pid namespace it's "active pid namespace",
and it is always the youngest pid namespace in which the process is known.
This patch defines and uses a wrapper to find the active pid namespace of a
process. The implementation of the wrapper will be changed in when support
for multiple pid namespaces are added.
Changelog:
2.6.22-rc4-mm2-pidns1:
- [Pavel Emelianov, Alexey Dobriyan] Back out the change to use
task_active_pid_ns() in child_reaper() since task->nsproxy
can be NULL during task exit (so child_reaper() continues to
use init_pid_ns).
to implement child_reaper() since init_pid_ns.child_reaper to
implement child_reaper() since tsk->nsproxy can be NULL during exit.
2.6.21-rc6-mm1:
- Rename task_pid_ns() to task_active_pid_ns() to reflect that a
process can have multiple pid namespaces.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Acked-by: Pavel Emelianov <xemul@openvz.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: Herbert Poetzel <herbert@13thfloor.at> Cc: Kirill Korotaev <dev@sw.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pavel Emelianov [Fri, 19 Oct 2007 06:39:48 +0000 (23:39 -0700)]
pid namespaces: dynamic kmem cache allocator for pid namespaces
Add kmem_cache to pid_namespace to allocate pids from.
Since both implementations expand the struct pid to carry more numerical
values each namespace should have separate cache to store pids of different
sizes.
Each kmem cache is name "pid_<NR>", where <NR> is the number of numerical ids
on the pid. Different namespaces with same level of nesting will have same
caches.
This patch has two FIXMEs that are to be fixed after we reach the consensus
about the struct pid itself.
The first one is that the namespace to free the pid from in free_pid() must be
taken from pid. Now the init_pid_ns is used.
The second FIXME is about the cache allocation. When we do know how long the
object will be then we'll have to calculate this size in create_pid_cachep.
Right now the sizeof(struct pid) value is used.
[akpm@linux-foundation.org: coding-style repair] Signed-off-by: Pavel Emelianov <xemul@openvz.org> Acked-by: Cedric Le Goater <clg@fr.ibm.com> Acked-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pavel Emelianov [Fri, 19 Oct 2007 06:39:46 +0000 (23:39 -0700)]
pid namespaces: round up the API
The set of functions process_session, task_session, process_group and
task_pgrp is confusing, as the names can be mixed with each other when looking
at the code for a long time.
The proposals are to
* equip the functions that return the integer with _nr suffix to
represent that fact,
* and to make all functions work with task (not process) by making
the common prefix of the same name.
For monotony the routines signal_session() and set_signal_session() are
replaced with task_session_nr() and set_task_session(), especially since they
are only used with the explicit task->signal dereference.
Signed-off-by: Pavel Emelianov <xemul@openvz.org> Acked-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Serge E. Hallyn [Fri, 19 Oct 2007 06:39:45 +0000 (23:39 -0700)]
cgroups: implement namespace tracking subsystem
When a task enters a new namespace via a clone() or unshare(), a new cgroup
is created and the task moves into it.
This version names cgroups which are automatically created using
cgroup_clone() as "node_<pid>" where pid is the pid of the unsharing or
cloned process. (Thanks Pavel for the idea) This is safe because if the
process unshares again, it will create
/cgroups/(...)/node_<pid>/node_<pid>
The only possibilities (AFAICT) for a -EEXIST on unshare are
1. pid wraparound
2. a process fails an unshare, then tries again.
Case 1 is unlikely enough that I ignore it (at least for now). In case 2, the
node_<pid> will be empty and can be rmdir'ed to make the subsequent unshare()
succeed.
Changelog:
Name cloned cgroups as "node_<pid>".
[clg@fr.ibm.com: fix order of cgroup subsystems in init/Kconfig] Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Paul Menage <menage@google.com> Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Balbir Singh [Fri, 19 Oct 2007 06:39:44 +0000 (23:39 -0700)]
Add cgroupstats
This patch is inspired by the discussion at
http://lkml.org/lkml/2007/4/11/187 and implements per cgroup statistics
as suggested by Andrew Morton in http://lkml.org/lkml/2007/4/11/263. The
patch is on top of 2.6.21-mm1 with Paul's cgroups v9 patches (forward
ported)
This patch implements per cgroup statistics infrastructure and re-uses
code from the taskstats interface. A new set of cgroup operations are
registered with commands and attributes. It should be very easy to
*extend* per cgroup statistics, by adding members to the cgroupstats
structure.
The current model for cgroupstats is a pull, a push model (to post
statistics on interesting events), should be very easy to add. Currently
user space requests for statistics by passing the cgroup file
descriptor. Statistics about the state of all the tasks in the cgroup
is returned to user space.
TODO's/NOTE:
This patch provides an infrastructure for implementing cgroup statistics.
Based on the needs of each controller, we can incrementally add more statistics,
event based support for notification of statistics, accumulation of taskstats
into cgroup statistics in the future.
Paul Jackson [Fri, 19 Oct 2007 06:39:43 +0000 (23:39 -0700)]
task cgroups: enable cgroups by default in some configs
In pre-cgroup cpusets, a few config files enabled cpusets by default.
Signed-off-by: Paul Jackson <pj@sgi.com> Cc: Paul Menage <menage@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Paul Menage [Fri, 19 Oct 2007 06:39:42 +0000 (23:39 -0700)]
Task Control Groups: example CPU accounting subsystem
This example demonstrates how to use the generic cgroup subsystem for a
simple resource tracker that counts, for the processes in a cgroup, the
total CPU time used and the %CPU used in the last complete 10 second interval.
Portions contributed by Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Paul Menage <menage@google.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Paul Menage [Fri, 19 Oct 2007 06:39:39 +0000 (23:39 -0700)]
Task Control Groups: make cpusets a client of cgroups
Remove the filesystem support logic from the cpusets system and makes cpusets
a cgroup subsystem
The "cpuset" filesystem becomes a dummy filesystem; attempts to mount it get
passed through to the cgroup filesystem with the appropriate options to
emulate the old cpuset filesystem behaviour.
Signed-off-by: Paul Menage <menage@google.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Paul Menage [Fri, 19 Oct 2007 06:39:38 +0000 (23:39 -0700)]
Task Control Groups: automatic userspace notification of idle cgroups
Add the following files to the cgroup filesystem:
notify_on_release - configures/reports whether the cgroup subsystem should
attempt to run a release script when this cgroup becomes unused
release_agent - configures/reports the release agent to be used for this
hierarchy (top level in each hierarchy only)
releasable - reports whether this cgroup would have been auto-released if
notify_on_release was true and a release agent was configured (mainly useful
for debugging)
To avoid locking issues, invoking the userspace release agent is done via a
workqueue task; cgroups that need to have their release agents invoked by
the workqueue task are linked on to a list.
[pj@sgi.com: Need to include kmod.h] Signed-off-by: Paul Menage <menage@google.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Paul Menage [Fri, 19 Oct 2007 06:39:36 +0000 (23:39 -0700)]
Task Control Groups: shared cgroup subsystem group arrays
Replace the struct css_set embedded in task_struct with a pointer; all tasks
that have the same set of memberships across all hierarchies will share a
css_set object, and will be linked via their css_sets field to the "tasks"
list_head in the css_set.
Assuming that many tasks share the same cgroup assignments, this reduces
overall space usage and keeps the size of the task_struct down (three pointers
added to task_struct compared to a non-cgroups kernel, no matter how many
subsystems are registered).
[akpm@linux-foundation.org: fix a printk]
[akpm@linux-foundation.org: build fix] Signed-off-by: Paul Menage <menage@google.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Paul Menage [Fri, 19 Oct 2007 06:39:34 +0000 (23:39 -0700)]
Task Control Groups: add cgroup_clone() interface
Add support for cgroup_clone(), a way to create new cgroups intended to
be used for systems such as namespace unsharing. A new subsystem callback,
post_clone(), is added to allow subsystems to automatically configure cloned
cgroups.
Signed-off-by: Paul Menage <menage@google.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Paul Menage [Fri, 19 Oct 2007 06:39:33 +0000 (23:39 -0700)]
Task Control Groups: add fork()/exit() hooks
This adds the necessary hooks to the fork() and exit() paths to ensure
that new children inherit their parent's cgroup assignments, and that
exiting processes release reference counts on their cgroups.
Signed-off-by: Paul Menage <menage@google.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Paul Menage [Fri, 19 Oct 2007 06:39:33 +0000 (23:39 -0700)]
Add cgroup write_uint() helper method
Add write_uint() helper method for cgroup subsystems
This helper is analagous to the read_uint() helper method for
reporting u64 values to userspace. It's designed to reduce the amount
of boilerplate requierd for creating new cgroup subsystems.
Signed-off-by: Paul Menage <menage@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Paul Menage [Fri, 19 Oct 2007 06:39:32 +0000 (23:39 -0700)]
Task Control Groups: add tasks file interface
Add the per-directory "tasks" file for cgroupfs mounts; this allows the
user to determine which tasks are members of a cgroup by reading a
cgroup's "tasks", and to move a task into a cgroup by writing its pid to
its "tasks".
Signed-off-by: Paul Menage <menage@google.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Paul Menage [Fri, 19 Oct 2007 06:39:30 +0000 (23:39 -0700)]
Task Control Groups: basic task cgroup framework
Generic Process Control Groups
--------------------------
There have recently been various proposals floating around for
resource management/accounting and other task grouping subsystems in
the kernel, including ResGroups, User BeanCounters, NSProxy
cgroups, and others. These all need the basic abstraction of being
able to group together multiple processes in an aggregate, in order to
track/limit the resources permitted to those processes, or control
other behaviour of the processes, and all implement this grouping in
different ways.
This patchset provides a framework for tracking and grouping processes
into arbitrary "cgroups" and assigning arbitrary state to those
groupings, in order to control the behaviour of the cgroup as an
aggregate.
The intention is that the various resource management and
virtualization/cgroup efforts can also become task cgroup
clients, with the result that:
- the userspace APIs are (somewhat) normalised
- it's easier to test e.g. the ResGroups CPU controller in
conjunction with the BeanCounters memory controller, or use either of
them as the resource-control portion of a virtual server system.
- the additional kernel footprint of any of the competing resource
management systems is substantially reduced, since it doesn't need
to provide process grouping/containment, hence improving their
chances of getting into the kernel
This patch:
Add the main task cgroups framework - the cgroup filesystem, and the
basic structures for tracking membership and associating subsystem state
objects to tasks.
Signed-off-by: Paul Menage <menage@google.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Paul Jackson [Fri, 19 Oct 2007 06:39:28 +0000 (23:39 -0700)]
cpuset: zero malloc - revert the old cpuset fix
The cpuset code to present a list of tasks using a cpuset to user space could
write to an array that it had kmalloc'd, after a kmalloc request of zero size.
The problem was that the code didn't check for writes past the allocated end
of the array until -after- the first write.
This is a race condition that is likely rare -- it would only show up if a
cpuset went from being empty to having a task in it, during the brief time
between the allocation and the first write.
Prior to roughly 2.6.22 kernels, this was also a benign problem, because a
zero kmalloc returned a few usable bytes anyway, and no harm was done with the
bogus write.
With the 2.6.22 kernel changes to make issue a warning if code tries to write
to the location returned from a zero size allocation, this problem is no
longer benign. This cpuset code would occassionally trigger that warning.
The fix is trivial -- check before storing into the array, not after, whether
the array is big enough to hold the store.
Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: "Serge E. Hallyn" <serue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Kirill Korotaev <dev@openvz.org> Cc: Paul Menage <menage@google.com> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: Christoph Lameter <clameter@sgi.com> Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Randy Dunlap [Fri, 19 Oct 2007 06:39:28 +0000 (23:39 -0700)]
kernel-api docbook: fix content problems
Fix kernel-api docbook contents problems.
docproc: linux-2.6.23-git13/include/asm-x86/unaligned_32.h: No such file or directory
Warning(linux-2.6.23-git13//include/linux/list.h:482): bad line: of list entry
Warning(linux-2.6.23-git13//mm/filemap.c:864): No description found for parameter 'ra'
Warning(linux-2.6.23-git13//block/ll_rw_blk.c:3760): No description found for parameter 'req'
Warning(linux-2.6.23-git13//include/linux/input.h:1077): No description found for parameter 'private'
Warning(linux-2.6.23-git13//include/linux/input.h:1077): No description found for parameter 'cdev'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: WU Fengguang <wfg@mail.ustc.edu.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Mahoney [Fri, 19 Oct 2007 06:39:27 +0000 (23:39 -0700)]
reiserfs: ignore on disk s_bmap_nr value
Implement support for file systems larger than 8 TiB.
The reiserfs superblock contains a 16 bit value for counting the number of
bitmap blocks. The rest of the disk format supports file systems up to 2^32
blocks, but the bitmap block limitation artificially limits this to 8 TiB with
a 4KiB block size.
Rather than trust the superblock's 16-bit bitmap block count, we calculate it
dynamically based on the number of blocks in the file system. When an
incorrect value is observed in the superblock, it is zeroed out, ensuring that
older kernels will not be able to mount the file system.
Userspace support has already been implemented and shipped in reiserfsprogs
3.6.20.
Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Mahoney [Fri, 19 Oct 2007 06:39:26 +0000 (23:39 -0700)]
reiserfs: remove first_zero_hint
The first_zero_hint metadata caching was never actually used, and it's of
dubious optimization quality. This patch removes it.
It doesn't actually shrink the size of the reiserfs_bitmap_info struct, since
that doesn't work with block sizes larger than 8K. There was a big fixme in
there, and with all the work lately in allowing block size > page size, I
might as well kill the fixme as well.
Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Mahoney [Fri, 19 Oct 2007 06:39:25 +0000 (23:39 -0700)]
reiserfs: fix usage of signed ints for block numbers
Do a quick signedness check for block numbers. There are a number of places
where signed integers are used for block numbers, which limits the usable file
system size to 8 TiB. The disk format, excepting a problem which will be
fixed in the following patch, supports file systems up to 16 TiB in size.
This patch cleans up those sites so that we can enable the full usable size.
Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Mahoney [Fri, 19 Oct 2007 06:39:25 +0000 (23:39 -0700)]
reiserfs: fix memset byte count during resize
Correct the memset in reiserfs_resize to clear the memory allocated for the
new bitmap info structs. Previously, it would clear the memory used by the
old size. Depending on the contents of memory, this could cause incorrect
caching behavior for bitmap blocks in the newly allocated area.
Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Mahoney [Fri, 19 Oct 2007 06:39:24 +0000 (23:39 -0700)]
reiserfs: dont use BUG when panicking
Change reiserfs_panic() to use panic() initially instead of BUG(). Using
BUG() ignores the configurable panic behavior, so systems that should be
failing and rebooting are left hanging. This causes problems in
active/standby HA scenarios.
Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jose R. Santos [Fri, 19 Oct 2007 06:39:23 +0000 (23:39 -0700)]
JBD: Fix JBD warnings when compiling with CONFIG_JBD_DEBUG
Note from Mingming's JBD2 fix:
Noticed all warnings are occurs when the debug level is 0. Then found the
"jbd2: Move jbd2-debug file to debugfs" patch
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=0f49d5d019afa4e94253bfc92f0daca3badb990b
changed the jbd2_journal_enable_debug from int type to u8, makes the
jbd_debug comparision is always true when the debugging level is 0. Thus
the compile warning occurs.
Thought about changing the jbd2_journal_enable_debug data type back to int,
but can't, because the jbd2-debug is moved to debug fs, where calling
debugfs_create_u8() to create the debugfs entry needs the value to be u8
type.
Even if we changed the data type back to int, the code is still buggy,
kernel should not print jbd2 debug message if the jbd2_journal_enable_debug
is set to 0. But this is not the case.
The fix is change the level of debugging to 1. The same should fixed in
ext3/JBD, but currently ext3 jbd-debug via /proc fs is broken, so we
probably should fix it all together.
Signed-off-by: Jose R. Santos <jrs@us.ibm.com> Cc: <linux-ext4@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Kara [Fri, 19 Oct 2007 06:39:22 +0000 (23:39 -0700)]
jbd: fix commit code to properly abort journal
We should really call journal_abort() and not __journal_abort_hard() in
case of errors. The latter call does not record the error in the journal
superblock and thus filesystem won't be marked as with errors later (and
user could happily mount it without any warning).
Signed-off-by: Jan Kara <jack@suse.cz> Cc: <linux-ext4@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jose R. Santos [Fri, 19 Oct 2007 06:39:22 +0000 (23:39 -0700)]
jbd: config_jbd_debug cannot create /proc entry
The jbd-debug file used to be located in /proc/sys/fs/jbd-debug, but
create_proc_entry() does not do lookups on file names that are more that
one directory deep. This causes the entry creation to fail and hence, no
proc file is created.
Instead of fixing this on procfs might as well move the jbd2-debug file to
debugfs which would be the preferred location for this kind of tunable.
The new location is now /sys/kernel/debug/jbd/jbd-debug.
[akpm@linux-foundation.org: zillions of cleanups] Signed-off-by: Jose R. Santos <jrs@us.ibm.com> Acked-by: Jan Kara <jack@suse.cz> Cc: <linux-ext4@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
isdn/sc: remove unused REQUEST_IRQ and unnecessary header file
REQUEST_IRQ is never used, so delete it. In the process get rid of the
macro FREE_IRQ which makes the code unnecessarily difficult to read.
Signed-off-by: Fernando Luis Vázquez Cao <fernando@oss.ntt.co.jp> Acked-by: Karsten Keil <kkeil@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Samuel Thibault [Fri, 19 Oct 2007 06:39:17 +0000 (23:39 -0700)]
Console events and accessibility
Some external modules like Speakup need to monitor console output.
This adds a VT notifier that such modules can use to get console output events:
allocation, deallocation, writes, other updates (cursor position, switch, etc.)
[akpm@linux-foundation.org: fix headers_check] Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Cc: Dmitry Torokhov <dtor@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
copy_oldmem_page should not return leaving a page frame from the
previous kernel mapped.
Signed-off-by: Fernando Luis Vázquez Cao <fernando@oss.ntt.co.jp> Acked-by: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ps3av: remove unused fields in ps3av_monitor_quirks
Remove the `clear_50' and `clear_vesa' fields of struct
ps3av_monitor_quirk, as they're currently unused. We can always re-add
them when we really need them.
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Samuel Thibault [Fri, 19 Oct 2007 06:39:12 +0000 (23:39 -0700)]
Console keyboard events and accessibility
Some blind people use a kernel engine called Speakup which uses hardware
synthesis to speak what gets displayed on the screen. They use the
PC keyboard to control this engine (start/stop, accelerate, ...) and
also need to get keyboard feedback (to make sure to know what they are
typing, the caps lock status, etc.)
Up to now, the way it was done was very ugly. Below is a patch to add a
notifier list for permitting a far better implementation, see ChangeLog
above for details.
You may wonder why this can't be done at the input layer. The problem
is that what people want to monitor is the console keyboard, i.e. all
input keyboards that got attached to the console, and with the currently
active keymap (i.e. keysyms, not only keycodes).
This adds a keyboard notifier that such modules can use to get the keyboard
events and possibly eat them, at several stages:
- keycodes: even before translation into keysym.
- unbound keycodes: when no keysym is bound.
- unicode: when the keycode would get translated into a unicode character.
- keysym: when the keycode would get translated into a keysym.
- post_keysym: after the keysym got interpreted, so as to see the result
(caps lock, etc.)
This also provides access to k_handler so as to permit simulation of
keypresses.
[akpm@linux-foundation.org: various fixes] Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Dmitry Torokhov <dtor@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Morton [Fri, 19 Oct 2007 06:39:10 +0000 (23:39 -0700)]
advansys: depends on VIRT_TO_BUS
Fix powerpc allmodconfig build: advansys requires virt_to_bus() but powerpc
doesn't implement it.
Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Paul Mackerras <paulus@samba.org> Acked-by: Matthew Wilcox <willy@linux.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>
Majority of host drivers using IDE PCI layer set drive->autotune, the only
exceptions are:
generic.c
ns87415.c
rz1000.c
trm290.c
* no ->set_pio_mode method
it821x.c:
* if memory allocation fails drive->autotune won't be set
(but there also won't be ->set_pio_mode method in such case)
piix.c:
* MPIIX controller (no ->init_hwif method so also no ->set_pio_mode method)
However if there is no ->set_pio_mode method there are no changes in behavior
w.r.t. PIO tuning so always set drive->autotune in ide_pci_setup_ports().
Add IDE_HFLAG_LEGACY_IRQS host flag to tell ide_pci_setup_ports() to set
hwif->irq to legacy IRQ 14/15 (iff hwif->irq is not already set) and convert
atiixp, piix, serverworks, sis5513 and slc90e66 host drivers to use it.
While at it:
* In piix.c add IDE_HFLAGS_PIIX define and don't use ->init_hwif for MPIIX.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Add IDE_HFLAG_SERIALIZE host flag to tell ide_pci_setup_ports() to set
hwif/mate->serialized and convert aec62xx, cs5530 and sc1200 host drivers
to use it.
Add IDE_HFLAG_ERROR_STOPS_FIFO host flag and use it instead
of hwif->err_stops_fifo. As a side-effect this change fixes
hwif->err_stops_fifo not being restored by ide_hwif_restore().
* Split off hpt{374,371,366}_init() helper from init_setup_hpt{374,371,366}().
* Merge init_setup_{374,372n,371,372a,302,366}() into hpt366_init_one().
While at it:
* Use "HPT36x" name for HPT366/HPT368 chipsets.
* Add .chip_name to struct hpt_info and use it to set set d->name.
* Convert .max_ultra in struct hpt_info to .udma_mask and use it to set
d->udma_mask.
* Fix hpt302 to use HPT302_ALLOW_ATA133_6 define.
* Change HPT366/HPT374 interrupt fixup message from KERN_WARNING to KERN_INFO.
* Use the second hpt366_chipsets[] entry for HPT37x chipsets using HPT36x PCI
device ID and fix .enablebits/.host_flags for HPT36x hpt366_chipsets[] entry.
* Bump driver version.
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
ide: add ->mwdma_mask and ->swdma_mask to ide_pci_device_t (take 2)
* Add ->mwdma_mask and ->swdma_mask to ide_pci_device_t.
* Set ide_hwif_t DMA masks using DMA masks from ide_pci_device_t in
setup-pci.c::ide_pci_setup_ports() (iff DMA base is valid and ->init_hwif
method may still override them).
* Convert IDE PCI host drivers to use ide_pci_device_t DMA masks.
While at it:
* Use ATA_{UDMA,MWDMA,SWDMA}* defines.
* hpt34x.c: add separate ide_pci_device_t instances for HPT343 and HPT345.
* serverworks.c: fix DMA masks being set before checking DMA base.
v2:
* Add missing masks to DECLARE_GENERIC_PCI_DEV() macro.
ide: add IDE_HFLAG_NO_LBA48 and IDE_HFLAG_NO_LBA48_DMA host flags
Add IDE_HFLAG_NO_LBA48[_DMA] host flags, use it instead of hwif->no_lba48[_dma]
and then remove no longer needed hwif->no_lba48[_dma]. As a side-effect
this change fixes hwif->no_lba48_dma not being restored by ide_hwif_restore().
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
ide: remove ->init_setup_dma from ide_pci_device_t (take 2)
* Make ide_pci_device_t.host_flags u32 and add IDE_HFLAG_CS5520 host flag.
* Pass ide_pci_device_t *d to setup-pci.c::ide_get_or_set_dma_base()
and use d->name instead of hwif->cds->name.
* Set IDE_HFLAG_CS5520 host flag in cs5520 host driver and use it in
ide_get_or_set_dma_base() to find out which PCI BAR to use, remove no longer
needed cs5520.c::cs5520_init_setup_dma() and ide_pci_device_t.init_setup_dma.
This fixes PCI bus-mastering not being checked for CS5510/CS5520 hosts.
v2:
* It is wrong to check simplex bits on CS5510/CS5520 as v1 did.
(Noticed by Alan).
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Add IDE_HFLAG_NO_{DMA,AUTODMA} host flags. Convert all host drivers using
ide_pci_device_t to use these flags instead of d->autodma and then remove no
longer needed d->autodma.
Add IDE_HFLAG_BOOTABLE host flag and IDE_HFLAG_OFF_BOARD define. Convert
all host drivers using ide_pci_device_t to use IDE_HFLAG_{BOOTABLE,OFF_BOARD}
instead of d->bootable and then remove no longer needed d->bootable.
* ssh://master.kernel.org/pub/scm/linux/kernel/git/tglx/linux-2.6-hrt:
hrtimer: hook compat_sys_nanosleep up to high res timer code
hrtimer: Rework hrtimer_nanosleep to make sys_compat_nanosleep easier
Linus Torvalds [Thu, 18 Oct 2007 22:08:35 +0000 (15:08 -0700)]
Merge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev
* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev:
[libata] kill ata_sg_is_last()
Update libata driver for bf548 atapi controller against the 2.6.24 tree.
libata-sff: Correct use of check_status()
drivers/ata: add support to Freescale 3.0Gbps SATA Controller
pata_acpi: fix build breakage if !CONFIG_PM
Linus Torvalds [Thu, 18 Oct 2007 21:51:02 +0000 (14:51 -0700)]
Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] time: Move R4000 clockevent device code to separate configurable file
[MIPS] time: Delete dead cycles_per_jiffy, mips_timer_ack and null_timer_ack
[MIPS] IP32: Retire use of plat_timer_setup.
[MIPS] Jazz: Retire use of plat_timer_setup.
[MIPS] IP27: Convert to clock_event_device.
[MIPS] JMR3927: Convert to clock_event_device.
[MIPS] Always do the ARC64_TWIDDLE_PC thing.
Linus Torvalds [Thu, 18 Oct 2007 21:40:30 +0000 (14:40 -0700)]
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
* 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6: (51 commits)
[IPV6]: Fix again the fl6_sock_lookup() fixed locking
[NETFILTER]: nf_conntrack_tcp: fix connection reopening fix
[IPV6]: Fix race in ipv6_flowlabel_opt() when inserting two labels
[IPV6]: Lost locking in fl6_sock_lookup
[IPV6]: Lost locking when inserting a flowlabel in ipv6_fl_list
[NETFILTER]: xt_sctp: fix mistake to pass a pointer where array is required
[NET]: Fix OOPS due to missing check in dev_parse_header().
[TCP]: Remove lost_retrans zero seqno special cases
[NET]: fix carrier-on bug?
[NET]: Fix uninitialised variable in ip_frag_reasm()
[IPSEC]: Rename mode to outer_mode and add inner_mode
[IPSEC]: Disallow combinations of RO and AH/ESP/IPCOMP
[IPSEC]: Use the top IPv4 route's peer instead of the bottom
[IPSEC]: Store afinfo pointer in xfrm_mode
[IPSEC]: Add missing BEET checks
[IPSEC]: Move type and mode map into xfrm_state.c
[IPSEC]: Fix length check in xfrm_parse_spi
[IPSEC]: Move ip_summed zapping out of xfrm6_rcv_spi
[IPSEC]: Get nexthdr from caller in xfrm6_rcv_spi
[IPSEC]: Move tunnel parsing for IPv4 out of xfrm4_input
...
Linus Torvalds [Thu, 18 Oct 2007 21:39:44 +0000 (14:39 -0700)]
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6
* 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6:
[SPARC/64]: Consolidate of_register_driver
[SPARC] Videopix Frame Grabber: Convert device_lock_sem to mutex
[SPARC]: Support for new termios.
[SPARC64]: Check of_get_property() return in pci_determine_mem_io_space().
[SPARC64]: Fix boot failures due to bootmem.
[SPARC64]: Implement atomic backoff.