k10sensor/src/k10sensor_link.c

/**
 * $Id: k10sensor_link.c 743 2012-06-18 06:10:35Z elkner $
 *
 * * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at
 * http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each file.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * All Rights reserved.
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2012 by Jens Elkner,
 * Otto-von-Guericke Universitaet Magdeburg. All rights reserved.
 */

/*
 * Admins like to just 'cat /dev/$device/$xy' and get all related info -
 * no need for extra utils or to keep more garbage in their head ;-)
 */
#include <strings.h>
#include <stdio.h>
#include <sys/dtrace.h>

#ifdef HAVE_DEVFSADM_H

#include <devfsadm.h>

#else

/* duplicate required stuff from usr/src/cmd/devfsadm/devfsadm.h */
#include <libdevinfo.h>

typedef struct devfsadm_create {
    char *device_class;     /* eg "disk", "tape", "display" */
    char *node_type;        /* eg DDI_NT_TAPE, DDI_NT_BLOCK, etc */
    char *drv_name;         /* eg sd, ssd */
    int flags;              /* TYPE_{EXACT,RE,PARTIAL}, DRV_{EXACT,RE} */
    int interpose_lvl;      /* eg ILEVEL_0.. ILEVEL_10 */
    int (*callback_fcn)(di_minor_t minor, di_node_t node);
} devfsadm_create_t;

typedef struct _devfsadm_create_reg {
    uint_t version;
    uint_t count;           /* number of node type registration */
    /* structures */
    devfsadm_create_t *tblp;
} _devfsadm_create_reg_t;

#define ILEVEL_0 0
#define TYPE_EXACT 0x01
#define DEVFSADM_V0 0
#define DEVFSADM_CONTINUE 0
#define DEVFSADM_TERMINATE 1

#define DEVFSADM_CREATE_INIT_V0(tbl) \
    _devfsadm_create_reg_t _devfsadm_create_reg = { \
        DEVFSADM_V0, (sizeof (tbl) / sizeof (devfsadm_create_t)), \
        ((devfsadm_create_t *)(tbl)) \
    }

#endif

#define MAXDEVCHARS 32
static int devfs_k10sensor_ln(di_minor_t minor, di_node_t node);

static devfsadm_create_t devfs_k10sensor_create_cbt[] = {
    { "pseudo", "ddi_pseudo", NULL, TYPE_EXACT, ILEVEL_0, devfs_k10sensor_ln }
};

DEVFSADM_CREATE_INIT_V0(devfs_k10sensor_create_cbt);

/* Create /dev/k10sensor/$instance links to the real device path like
 * /devices/pci@0,0/pci1022,1103@18,3:k10sensor */
static int
devfs_k10sensor_ln(di_minor_t minor, di_node_t node)
{
    char devname[MAXDEVCHARS];
    char *mn;

    if (strcmp(di_driver_name(node), KMODNAME) != 0) {
        return (DEVFSADM_CONTINUE);
    }
    if (di_minor_name(minor) == NULL) {
        return (DEVFSADM_CONTINUE);
    }
    devname[0] = '\0';
    if (snprintf(devname, MAXDEVCHARS, "%s/%d", KMODNAME, minor->dev_minor)
        >= MAXDEVCHARS)
    {
        return (DEVFSADM_CONTINUE); /* not enough space */
    }

    /* devfsadm_mklink() one is actually part of devfsadm - we use mapfile-vars
       to make ld happy */
    (void) devfsadm_mklink(devname, node, minor, 0);
    return (DEVFSADM_CONTINUE);
}