source: rtems-libbsd/rtemsbsd/powerpc/include/linux/sysfs.h @ 0f1d2f6

/*-
 * 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_

#if 0
#include <sys/sysctl.h>

struct attribute {
        const char      *name;
        struct module   *owner;
        mode_t          mode;
};

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 *)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

#endif  /* _LINUX_SYSFS_H_ */