Commit d5f68d33 authored by Al Viro's avatar Al Viro
Browse files

cpuset: move mount -t cpuset logics into cgroup.c 



... and get rid of the weird dances in ->get_tree() - that logics
can be easily handled in ->init_fs_context().

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 46cf047a

kernel/cgroup/cgroup.c

+47 −0
Original line number Diff line number Diff line
@@ -2225,6 +2225,50 @@ static struct file_system_type cgroup2_fs_type = { 
	.fs_flags		= FS_USERNS_MOUNT,

};



#ifdef CONFIG_CPUSETS

static const struct fs_context_operations cpuset_fs_context_ops = {

	.get_tree	= cgroup1_get_tree,

	.free		= cgroup_fs_context_free,

};



/*

 * This is ugly, but preserves the userspace API for existing cpuset

 * users. If someone tries to mount the "cpuset" filesystem, we

 * silently switch it to mount "cgroup" instead

 */

static int cpuset_init_fs_context(struct fs_context *fc)

{

	char *agent = kstrdup("/sbin/cpuset_release_agent", GFP_USER);

	struct cgroup_fs_context *ctx;

	int err;



	err = cgroup_init_fs_context(fc);

	if (err) {

		kfree(agent);

		return err;

	}



	fc->ops = &cpuset_fs_context_ops;



	ctx = cgroup_fc2context(fc);

	ctx->subsys_mask = 1 << cpuset_cgrp_id;

	ctx->flags |= CGRP_ROOT_NOPREFIX;

	ctx->release_agent = agent;



	get_filesystem(&cgroup_fs_type);

	put_filesystem(fc->fs_type);

	fc->fs_type = &cgroup_fs_type;



	return 0;

}



static struct file_system_type cpuset_fs_type = {

	.name			= "cpuset",

	.init_fs_context	= cpuset_init_fs_context,

	.fs_flags		= FS_USERNS_MOUNT,

};

#endif



int cgroup_path_ns_locked(struct cgroup *cgrp, char *buf, size_t buflen,

			  struct cgroup_namespace *ns)

{
@@ -5710,6 +5754,9 @@ int __init cgroup_init(void) 
	WARN_ON(register_filesystem(&cgroup_fs_type));

	WARN_ON(register_filesystem(&cgroup2_fs_type));

	WARN_ON(!proc_create_single("cgroups", 0, NULL, proc_cgroupstats_show));

#ifdef CONFIG_CPUSETS

	WARN_ON(register_filesystem(&cpuset_fs_type));

#endif



	return 0;

}

kernel/cgroup/cpuset.c

+1 −60
Original line number Diff line number Diff line
@@ -355,59 +355,6 @@ static inline bool is_in_v2_mode(void) 
	      (cpuset_cgrp_subsys.root->flags & CGRP_ROOT_CPUSET_V2_MODE);

}



/*

 * This is ugly, but preserves the userspace API for existing cpuset

 * users. If someone tries to mount the "cpuset" filesystem, we

 * silently switch it to mount "cgroup" instead

 */

static int cpuset_get_tree(struct fs_context *fc)

{

	struct file_system_type *cgroup_fs;

	struct fs_context *new_fc;

	int ret;



	cgroup_fs = get_fs_type("cgroup");

	if (!cgroup_fs)

		return -ENODEV;



	new_fc = fs_context_for_mount(cgroup_fs, fc->sb_flags);

	if (IS_ERR(new_fc)) {

		ret = PTR_ERR(new_fc);

	} else {

		static const char agent_path[] = "/sbin/cpuset_release_agent";

		ret = vfs_parse_fs_string(new_fc, "cpuset", NULL, 0);

		if (!ret)

			ret = vfs_parse_fs_string(new_fc, "noprefix", NULL, 0);

		if (!ret)

			ret = vfs_parse_fs_string(new_fc, "release_agent",

					agent_path, sizeof(agent_path) - 1);

		if (!ret)

			ret = vfs_get_tree(new_fc);

		if (!ret) {	/* steal the result */

			fc->root = new_fc->root;

			new_fc->root = NULL;

		}

		put_fs_context(new_fc);

	}

	put_filesystem(cgroup_fs);

	return ret;

}



static const struct fs_context_operations cpuset_fs_context_ops = {

	.get_tree	= cpuset_get_tree,

};



static int cpuset_init_fs_context(struct fs_context *fc)

{

	fc->ops = &cpuset_fs_context_ops;

	return 0;

}



static struct file_system_type cpuset_fs_type = {

	.name			= "cpuset",

	.init_fs_context	= cpuset_init_fs_context,

};



/*

 * Return in pmask the portion of a cpusets's cpus_allowed that

 * are online.  If none are online, walk up the cpuset hierarchy
@@ -2853,13 +2800,11 @@ struct cgroup_subsys cpuset_cgrp_subsys = { 
/**

 * cpuset_init - initialize cpusets at system boot

 *

 * Description: Initialize top_cpuset and the cpuset internal file system,

 * Description: Initialize top_cpuset

 **/



int __init cpuset_init(void)

{

	int err = 0;



	BUG_ON(!alloc_cpumask_var(&top_cpuset.cpus_allowed, GFP_KERNEL));

	BUG_ON(!alloc_cpumask_var(&top_cpuset.effective_cpus, GFP_KERNEL));

	BUG_ON(!zalloc_cpumask_var(&top_cpuset.subparts_cpus, GFP_KERNEL));
@@ -2873,10 +2818,6 @@ int __init cpuset_init(void) 
	set_bit(CS_SCHED_LOAD_BALANCE, &top_cpuset.flags);

	top_cpuset.relax_domain_level = -1;



	err = register_filesystem(&cpuset_fs_type);

	if (err < 0)

		return err;



	BUG_ON(!alloc_cpumask_var(&cpus_attach, GFP_KERNEL));



	return 0;