/*-
* Copyright (c) 2010 Isilon Systems, Inc.
* Copyright (c) 2010 iX Systems, Inc.
* Copyright (c) 2010 Panasas, Inc.
* Copyright (c) 2013, 2014 Mellanox Technologies, Ltd.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _LINUX_SYSFS_H_
#define _LINUX_SYSFS_H_
#include <sys/types.h>
#include <sys/sysctl.h>
#include <sys/errno.h>
#include <linux/kobject.h>
struct sysfs_ops {
ssize_t (*show)(struct kobject *, struct attribute *, char *);
ssize_t (*store)(struct kobject *, struct attribute *, const char *,
size_t);
};
struct attribute_group {
const char *name;
mode_t (*is_visible)(struct kobject *,
struct attribute *, int);
struct attribute **attrs;
};
#define __ATTR(_name, _mode, _show, _store) { \
.attr = { .name = __stringify(_name), .mode = _mode }, \
.show = _show, .store = _store, \
}
#define __ATTR_RO(_name) { \
.attr = { .name = __stringify(_name), .mode = 0444 }, \
.show = _name##_show, \
}
#define __ATTR_NULL { .attr = { .name = NULL } }
/*
* Handle our generic '\0' terminated 'C' string.
* Two cases:
* a variable string: point arg1 at it, arg2 is max length.
* a constant string: point arg1 at it, arg2 is zero.
*/
static inline int
sysctl_handle_attr(SYSCTL_HANDLER_ARGS)
{
struct kobject *kobj;
struct attribute *attr;
const struct sysfs_ops *ops;
char *buf;
int error;
ssize_t len;
kobj = arg1;
attr = (struct attribute *)(intptr_t)arg2;
if (kobj->ktype == NULL || kobj->ktype->sysfs_ops == NULL)
return (ENODEV);
buf = (char *)get_zeroed_page(GFP_KERNEL);
if (buf == NULL)
return (ENOMEM);
ops = kobj->ktype->sysfs_ops;
if (ops->show) {
len = ops->show(kobj, attr, buf);
/*
* It's valid to not have a 'show' so just return an
* empty string.
*/
if (len < 0) {
error = -len;
if (error != EIO)
goto out;
buf[0] = '\0';
} else if (len) {
len--;
if (len >= PAGE_SIZE)
len = PAGE_SIZE - 1;
/* Trim trailing newline. */
buf[len] = '\0';
}
}
/* Leave one trailing byte to append a newline. */
error = sysctl_handle_string(oidp, buf, PAGE_SIZE - 1, req);
if (error != 0 || req->newptr == NULL || ops->store == NULL)
goto out;
len = strlcat(buf, "\n", PAGE_SIZE);
KASSERT(len < PAGE_SIZE, ("new attribute truncated"));
len = ops->store(kobj, attr, buf, len);
if (len < 0)
error = -len;
out:
free_page((unsigned long)buf);
return (error);
}
static inline int
sysfs_create_file(struct kobject *kobj, const struct attribute *attr)
{
SYSCTL_ADD_OID(NULL, SYSCTL_CHILDREN(kobj->oidp), OID_AUTO,
attr->name, CTLTYPE_STRING|CTLFLAG_RW|CTLFLAG_MPSAFE, kobj,
(uintptr_t)attr, sysctl_handle_attr, "A", "");
return (0);
}
static inline void
sysfs_remove_file(struct kobject *kobj, const struct attribute *attr)
{
if (kobj->oidp)
sysctl_remove_name(kobj->oidp, attr->name, 1, 1);
}
static inline void
sysfs_remove_group(struct kobject *kobj, const struct attribute_group *grp)
{
if (kobj->oidp)
sysctl_remove_name(kobj->oidp, grp->name, 1, 1);
}
static inline int
sysfs_create_group(struct kobject *kobj, const struct attribute_group *grp)
{
struct attribute **attr;
struct sysctl_oid *oidp;
oidp = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(kobj->oidp),
OID_AUTO, grp->name, CTLFLAG_RD|CTLFLAG_MPSAFE, NULL, grp->name);
for (attr = grp->attrs; *attr != NULL; attr++) {
SYSCTL_ADD_OID(NULL, SYSCTL_CHILDREN(oidp), OID_AUTO,
(*attr)->name, CTLTYPE_STRING|CTLFLAG_RW|CTLFLAG_MPSAFE,
kobj, (uintptr_t)*attr, sysctl_handle_attr, "A", "");
}
return (0);
}
static inline int
sysfs_create_dir(struct kobject *kobj)
{
kobj->oidp = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(kobj->parent->oidp),
OID_AUTO, kobj->name, CTLFLAG_RD|CTLFLAG_MPSAFE, NULL, kobj->name);
return (0);
}
static inline void
sysfs_remove_dir(struct kobject *kobj)
{
if (kobj->oidp == NULL)
return;
sysctl_remove_oid(kobj->oidp, 1, 1);
}
#define sysfs_attr_init(attr) do {} while(0)
#endif /* _LINUX_SYSFS_H_ */
