linux-hardened/fs/exofs/sys.c
Peter Zijlstra 2c935bc572 locking/atomic, kref: Add kref_read()
Since we need to change the implementation, stop exposing internals.

Provide kref_read() to read the current reference count; typically
used for debug messages.

Kills two anti-patterns:

	atomic_read(&kref->refcount)
	kref->refcount.counter

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 11:37:18 +01:00

205 lines
5.3 KiB
C

/*
* Copyright (C) 2012
* Sachin Bhamare <sbhamare@panasas.com>
* Boaz Harrosh <ooo@electrozaur.com>
*
* This file is part of exofs.
*
* exofs is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License 2 as published by
* the Free Software Foundation.
*
* exofs is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with exofs; if not, write to the:
* Free Software Foundation <licensing@fsf.org>
*/
#include <linux/kobject.h>
#include <linux/device.h>
#include "exofs.h"
struct odev_attr {
struct attribute attr;
ssize_t (*show)(struct exofs_dev *, char *);
ssize_t (*store)(struct exofs_dev *, const char *, size_t);
};
static ssize_t odev_attr_show(struct kobject *kobj, struct attribute *attr,
char *buf)
{
struct exofs_dev *edp = container_of(kobj, struct exofs_dev, ed_kobj);
struct odev_attr *a = container_of(attr, struct odev_attr, attr);
return a->show ? a->show(edp, buf) : 0;
}
static ssize_t odev_attr_store(struct kobject *kobj, struct attribute *attr,
const char *buf, size_t len)
{
struct exofs_dev *edp = container_of(kobj, struct exofs_dev, ed_kobj);
struct odev_attr *a = container_of(attr, struct odev_attr, attr);
return a->store ? a->store(edp, buf, len) : len;
}
static const struct sysfs_ops odev_attr_ops = {
.show = odev_attr_show,
.store = odev_attr_store,
};
static struct kset *exofs_kset;
static ssize_t osdname_show(struct exofs_dev *edp, char *buf)
{
struct osd_dev *odev = edp->ored.od;
const struct osd_dev_info *odi = osduld_device_info(odev);
return snprintf(buf, odi->osdname_len + 1, "%s", odi->osdname);
}
static ssize_t systemid_show(struct exofs_dev *edp, char *buf)
{
struct osd_dev *odev = edp->ored.od;
const struct osd_dev_info *odi = osduld_device_info(odev);
memcpy(buf, odi->systemid, odi->systemid_len);
return odi->systemid_len;
}
static ssize_t uri_show(struct exofs_dev *edp, char *buf)
{
return snprintf(buf, edp->urilen, "%s", edp->uri);
}
static ssize_t uri_store(struct exofs_dev *edp, const char *buf, size_t len)
{
uint8_t *new_uri;
edp->urilen = strlen(buf) + 1;
new_uri = krealloc(edp->uri, edp->urilen, GFP_KERNEL);
if (new_uri == NULL)
return -ENOMEM;
edp->uri = new_uri;
strncpy(edp->uri, buf, edp->urilen);
return edp->urilen;
}
#define OSD_ATTR(name, mode, show, store) \
static struct odev_attr odev_attr_##name = \
__ATTR(name, mode, show, store)
OSD_ATTR(osdname, S_IRUGO, osdname_show, NULL);
OSD_ATTR(systemid, S_IRUGO, systemid_show, NULL);
OSD_ATTR(uri, S_IRWXU, uri_show, uri_store);
static struct attribute *odev_attrs[] = {
&odev_attr_osdname.attr,
&odev_attr_systemid.attr,
&odev_attr_uri.attr,
NULL,
};
static struct kobj_type odev_ktype = {
.default_attrs = odev_attrs,
.sysfs_ops = &odev_attr_ops,
};
static struct kobj_type uuid_ktype = {
};
void exofs_sysfs_dbg_print(void)
{
#ifdef CONFIG_EXOFS_DEBUG
struct kobject *k_name, *k_tmp;
list_for_each_entry_safe(k_name, k_tmp, &exofs_kset->list, entry) {
printk(KERN_INFO "%s: name %s ref %d\n",
__func__, kobject_name(k_name),
(int)kref_read(&k_name->kref));
}
#endif
}
/*
* This function removes all kobjects under exofs_kset
* At the end of it, exofs_kset kobject will have a refcount
* of 1 which gets decremented only on exofs module unload
*/
void exofs_sysfs_sb_del(struct exofs_sb_info *sbi)
{
struct kobject *k_name, *k_tmp;
struct kobject *s_kobj = &sbi->s_kobj;
list_for_each_entry_safe(k_name, k_tmp, &exofs_kset->list, entry) {
/* Remove all that are children of this SBI */
if (k_name->parent == s_kobj)
kobject_put(k_name);
}
kobject_put(s_kobj);
}
/*
* This function creates sysfs entries to hold the current exofs cluster
* instance (uniquely identified by osdname,pid tuple).
* This function gets called once per exofs mount instance.
*/
int exofs_sysfs_sb_add(struct exofs_sb_info *sbi,
struct exofs_dt_device_info *dt_dev)
{
struct kobject *s_kobj;
int retval = 0;
uint64_t pid = sbi->one_comp.obj.partition;
/* allocate new uuid dirent */
s_kobj = &sbi->s_kobj;
s_kobj->kset = exofs_kset;
retval = kobject_init_and_add(s_kobj, &uuid_ktype,
&exofs_kset->kobj, "%s_%llx", dt_dev->osdname, pid);
if (retval) {
EXOFS_ERR("ERROR: Failed to create sysfs entry for "
"uuid-%s_%llx => %d\n", dt_dev->osdname, pid, retval);
return -ENOMEM;
}
return 0;
}
int exofs_sysfs_odev_add(struct exofs_dev *edev, struct exofs_sb_info *sbi)
{
struct kobject *d_kobj;
int retval = 0;
/* create osd device group which contains following attributes
* osdname, systemid & uri
*/
d_kobj = &edev->ed_kobj;
d_kobj->kset = exofs_kset;
retval = kobject_init_and_add(d_kobj, &odev_ktype,
&sbi->s_kobj, "dev%u", edev->did);
if (retval) {
EXOFS_ERR("ERROR: Failed to create sysfs entry for "
"device dev%u\n", edev->did);
return retval;
}
return 0;
}
int exofs_sysfs_init(void)
{
exofs_kset = kset_create_and_add("exofs", NULL, fs_kobj);
if (!exofs_kset) {
EXOFS_ERR("ERROR: kset_create_and_add exofs failed\n");
return -ENOMEM;
}
return 0;
}
void exofs_sysfs_uninit(void)
{
kset_unregister(exofs_kset);
}