Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 74ae4e10 authored by Joel Becker's avatar Joel Becker Committed by Mark Fasheh
Browse files

ocfs2: Create stack glue sysfs files.



Introduce a set of sysfs files that describe the current stack glue
state.  The files live under /sys/fs/ocfs2.  The locking_protocol file
displays the version of ocfs2's locking code.  The
loaded_cluster_plugins file displays all of the currently loaded stack
plugins.  When filesystems are mounted, the active_cluster_plugin file
will display the plugin in use.

Signed-off-by: default avatarJoel Becker <joel.becker@oracle.com>
Signed-off-by: default avatarMark Fasheh <mfasheh@suse.com>
parent 286eaa95
Loading
Loading
Loading
Loading
+120 −1
Original line number Diff line number Diff line
@@ -23,6 +23,9 @@
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/kmod.h>
#include <linux/fs.h>
#include <linux/kobject.h>
#include <linux/sysfs.h>

#include "stackglue.h"

@@ -335,14 +338,130 @@ int ocfs2_cluster_this_node(unsigned int *node)
EXPORT_SYMBOL_GPL(ocfs2_cluster_this_node);


static int __init ocfs2_stack_glue_init(void)
/*
 * Sysfs bits
 */

static ssize_t ocfs2_max_locking_protocol_show(struct kobject *kobj,
					       struct kobj_attribute *attr,
					       char *buf)
{
	ssize_t ret = 0;

	spin_lock(&ocfs2_stack_lock);
	if (lproto)
		ret = snprintf(buf, PAGE_SIZE, "%u.%u\n",
			       lproto->lp_max_version.pv_major,
			       lproto->lp_max_version.pv_minor);
	spin_unlock(&ocfs2_stack_lock);

	return ret;
}

static struct kobj_attribute ocfs2_attr_max_locking_protocol =
	__ATTR(max_locking_protocol, S_IFREG | S_IRUGO,
	       ocfs2_max_locking_protocol_show, NULL);

static ssize_t ocfs2_loaded_cluster_plugins_show(struct kobject *kobj,
						 struct kobj_attribute *attr,
						 char *buf)
{
	ssize_t ret = 0, total = 0, remain = PAGE_SIZE;
	struct ocfs2_stack_plugin *p;

	spin_lock(&ocfs2_stack_lock);
	list_for_each_entry(p, &ocfs2_stack_list, sp_list) {
		ret = snprintf(buf, remain, "%s\n",
			       p->sp_name);
		if (ret < 0) {
			total = ret;
			break;
		}
		if (ret == remain) {
			/* snprintf() didn't fit */
			total = -E2BIG;
			break;
		}
		total += ret;
		remain -= ret;
	}
	spin_unlock(&ocfs2_stack_lock);

	return total;
}

static struct kobj_attribute ocfs2_attr_loaded_cluster_plugins =
	__ATTR(loaded_cluster_plugins, S_IFREG | S_IRUGO,
	       ocfs2_loaded_cluster_plugins_show, NULL);

static ssize_t ocfs2_active_cluster_plugin_show(struct kobject *kobj,
						struct kobj_attribute *attr,
						char *buf)
{
	ssize_t ret = 0;

	spin_lock(&ocfs2_stack_lock);
	if (active_stack) {
		ret = snprintf(buf, PAGE_SIZE, "%s\n",
			       active_stack->sp_name);
		if (ret == PAGE_SIZE)
			ret = -E2BIG;
	}
	spin_unlock(&ocfs2_stack_lock);

	return ret;
}

static struct kobj_attribute ocfs2_attr_active_cluster_plugin =
	__ATTR(active_cluster_plugin, S_IFREG | S_IRUGO,
	       ocfs2_active_cluster_plugin_show, NULL);

static struct attribute *ocfs2_attrs[] = {
	&ocfs2_attr_max_locking_protocol.attr,
	&ocfs2_attr_loaded_cluster_plugins.attr,
	&ocfs2_attr_active_cluster_plugin.attr,
	NULL,
};

static struct attribute_group ocfs2_attr_group = {
	.attrs = ocfs2_attrs,
};

static struct kset *ocfs2_kset;

static void ocfs2_sysfs_exit(void)
{
	kset_unregister(ocfs2_kset);
}

static int ocfs2_sysfs_init(void)
{
	int ret;

	ocfs2_kset = kset_create_and_add("ocfs2", NULL, fs_kobj);
	if (!ocfs2_kset)
		return -ENOMEM;

	ret = sysfs_create_group(&ocfs2_kset->kobj, &ocfs2_attr_group);
	if (ret)
		goto error;

	return 0;

error:
	kset_unregister(ocfs2_kset);
	return ret;
}

static int __init ocfs2_stack_glue_init(void)
{
	return ocfs2_sysfs_init();
}

static void __exit ocfs2_stack_glue_exit(void)
{
	lproto = NULL;
	ocfs2_sysfs_exit();
}

MODULE_AUTHOR("Oracle");