diff options
| author | Aleksa Sarai <cyphar@cyphar.com> | 2015-06-09 21:32:09 +1000 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2015-07-14 17:29:23 -0400 |
| commit | 7e47682ea555e7c1edef1d8fd96e2aa4c12abe59 (patch) | |
| tree | 6012cbc180ae7d633be4ed2ff1f1f6f7f188c1a0 /include/linux/cgroup_subsys.h | |
| parent | d770e558e21961ad6cfdf0ff7df0eb5d7d4f0754 (diff) | |
cgroup: allow a cgroup subsystem to reject a fork
Add a new cgroup subsystem callback can_fork that conditionally
states whether or not the fork is accepted or rejected by a cgroup
policy. In addition, add a cancel_fork callback so that if an error
occurs later in the forking process, any state modified by can_fork can
be reverted.
Allow for a private opaque pointer to be passed from cgroup_can_fork to
cgroup_post_fork, allowing for the fork state to be stored by each
subsystem separately.
Also add a tagging system for cgroup_subsys.h to allow for CGROUP_<TAG>
enumerations to be be defined and used. In addition, explicitly add a
CGROUP_CANFORK_COUNT macro to make arrays easier to define.
This is in preparation for implementing the pids cgroup subsystem.
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'include/linux/cgroup_subsys.h')
| -rw-r--r-- | include/linux/cgroup_subsys.h | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/include/linux/cgroup_subsys.h b/include/linux/cgroup_subsys.h index e4a96fb14403..ec43bce7e1ea 100644 --- a/include/linux/cgroup_subsys.h +++ b/include/linux/cgroup_subsys.h @@ -3,6 +3,17 @@ * * DO NOT ADD ANY SUBSYSTEM WITHOUT EXPLICIT ACKS FROM CGROUP MAINTAINERS. */ + +/* + * This file *must* be included with SUBSYS() defined. + * SUBSYS_TAG() is a noop if undefined. + */ + +#ifndef SUBSYS_TAG +#define __TMP_SUBSYS_TAG +#define SUBSYS_TAG(_x) +#endif + #if IS_ENABLED(CONFIG_CPUSETS) SUBSYS(cpuset) #endif @@ -48,11 +59,23 @@ SUBSYS(hugetlb) #endif /* + * Subsystems that implement the can_fork() family of callbacks. + */ +SUBSYS_TAG(CANFORK_START) +SUBSYS_TAG(CANFORK_END) + +/* * The following subsystems are not supported on the default hierarchy. */ #if IS_ENABLED(CONFIG_CGROUP_DEBUG) SUBSYS(debug) #endif + +#ifdef __TMP_SUBSYS_TAG +#undef __TMP_SUBSYS_TAG +#undef SUBSYS_TAG +#endif + /* * DO NOT ADD ANY SUBSYSTEM WITHOUT EXPLICIT ACKS FROM CGROUP MAINTAINERS. */ |