usmp/common/usmp.c

/*
 * 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 usr/src/OPENSOLARIS.LICENSE
 * or 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 and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * 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]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/scsi/scsi_address.h>
#include <sys/scsi/impl/usmp.h>
#include <sys/libdevid.h>

#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>
#include <strings.h>
#include <stdio.h>
#include <limits.h>

#include <scsi/libsmp.h>
#include <scsi/libsmp_plugin.h>

#include <libdevinfo.h>

struct usmp_dev {
    int ud_fd;
    char *ud_dev;
    uint64_t ud_addr;
};

struct di_walk_arg {
    dev_t dev;
    uint64_t addr;
};

static int
di_walk(di_node_t node, di_minor_t minor, void *arg)
{
    struct di_walk_arg *wp = arg;
    char *wwn;

    if (di_minor_spectype(minor) != S_IFCHR)
        return (DI_WALK_CONTINUE);

    if (di_minor_devt(minor) == wp->dev) {
        if (di_prop_lookup_strings(DDI_DEV_T_ANY, node,
            SCSI_ADDR_PROP_TARGET_PORT, &wwn) != 1 &&
            di_prop_lookup_strings(DDI_DEV_T_ANY, node,
            "smp-wwn", &wwn) != 1)
            return (DI_WALK_CONTINUE);

        if (scsi_wwnstr_to_wwn(wwn, &wp->addr) != DDI_SUCCESS)
            return (DI_WALK_CONTINUE);

        return (DI_WALK_TERMINATE);
    }

    return (DI_WALK_CONTINUE);
}

static void *
usmp_open(const void *target)
{
    struct usmp_dev *dp;
    const char *target_name = (const char *)target;

    struct stat64 st;
    di_node_t root, smp;
    struct di_walk_arg walk;

    if ((dp = smp_zalloc(sizeof (struct usmp_dev))) == NULL)
        return (NULL);

    if ((dp->ud_dev = smp_strdup(target_name)) == NULL) {
        smp_free(dp);
        return (NULL);
    }

    if ((dp->ud_fd = open(target_name, O_RDONLY)) < 0) {
        (void) smp_error(ESMP_BADTARGET,
            "failed to open %s for reading: %s",
            target_name, strerror(errno));
        smp_free(dp->ud_dev);
        smp_free(dp);
        return (NULL);
    }

    if (fstat64(dp->ud_fd, &st) != 0) {
        (void) smp_error(ESMP_BADTARGET,
            "failed to stat %s: %s", target_name, strerror(errno));
        (void) close(dp->ud_fd);
        smp_free(dp->ud_dev);
        smp_free(dp);
        return (NULL);
    }

    if ((root = di_init("/", DINFOCACHE)) != DI_NODE_NIL) {
        for (smp = di_drv_first_node("smp", root); smp != DI_NODE_NIL;
            smp = di_drv_next_node(smp)) {
            bzero(&walk, sizeof (walk));
            walk.dev = st.st_rdev;
            (void) di_walk_minor(smp, NULL, 0, &walk, di_walk);
            if (walk.addr != 0) {
                dp->ud_addr = walk.addr;
                break;
            }
        }
        di_fini(root);
    }

    return (dp);
}

static void
usmp_close(void *private)
{
    struct usmp_dev *dp = (struct usmp_dev *)private;

    if (dp == NULL)
        return;

    if (dp->ud_fd > 0)
        (void) close(dp->ud_fd);

    smp_free(dp->ud_dev);
    smp_free(dp);
}

static int
usmp_exec(void *private, smp_action_t *ap)
{
    struct usmp_dev *dp = (struct usmp_dev *)private;
    struct usmp_cmd cmd;
    void *req, *resp;
    size_t reqlen, resplen;

    bzero(&cmd, sizeof (cmd));

    smp_action_get_request_frame(ap, &req, &reqlen);
    smp_action_get_response_frame(ap, &resp, &resplen);

    ASSERT(req != NULL);
    ASSERT(resp != NULL);
    ASSERT(reqlen != 0);
    ASSERT(resplen != 0);

    cmd.usmp_req = req;
    cmd.usmp_reqsize = reqlen;
    cmd.usmp_rsp = resp;
    cmd.usmp_rspsize = resplen;
    cmd.usmp_timeout = (int)smp_action_get_timeout(ap);

    if (ioctl(dp->ud_fd, USMPFUNC, &cmd) < 0) {
        ASSERT(errno != EFAULT);
        switch (errno) {
        case EINVAL:
            return (smp_error(ESMP_BADFUNC, "internal usmp error"));
        case EPERM:
            return (smp_error(ESMP_PERM,
                "insufficient privileges"));
        case EIO:
            return (smp_error(ESMP_IO, "I/O error"));
        default:
            return (smp_error(ESMP_SYS, "usmp ioctl failed: %s",
                strerror(errno)));
        }
    }

    /*
     * There is no way to determine the amount of data actually transferred
     * so we will just place the upper bound at the allocated size.
     */
    smp_action_set_response_len(ap, resplen);

    return (0);
}

static void
usmp_target_name(void *private, char *buf, size_t len)
{
    struct usmp_dev *dp = (struct usmp_dev *)private;

    (void) strlcpy(buf, dp->ud_dev, len);
}

static uint64_t
usmp_target_addr(void *private)
{
    struct usmp_dev *dp = (struct usmp_dev *)private;

    return (dp->ud_addr);
}

static const smp_engine_ops_t usmp_ops = {
    .seo_open = usmp_open,
    .seo_close = usmp_close,
    .seo_exec = usmp_exec,
    .seo_target_name = usmp_target_name,
    .seo_target_addr = usmp_target_addr
};

int
_smp_init(smp_engine_t *ep)
{
    smp_engine_config_t config = {
        .sec_name = "usmp",
        .sec_ops = &usmp_ops
    };

    return (smp_engine_register(ep, LIBSMP_ENGINE_VERSION, &config));
}