modules/smbfs/smbfs.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 2011 Nexenta Systems, Inc.  All rights reserved.
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <sys/mdb_modapi.h>
#include <sys/types.h>
#include <sys/refstr_impl.h>
#include <sys/vnode.h>
#include <sys/vfs.h>

#include <smbfs/smbfs.h>
#include <smbfs/smbfs_node.h>

#define OPT_VERBOSE 0x0001  /* Be [-v]erbose in dcmd's */

/*
 * This macro lets us easily use both sizeof (typename)
 * and the string-ified typename for the error message.
 */
#define SMBFS_OBJ_FETCH(obj_addr, obj_type, dest, err) \
    if (mdb_vread(dest, sizeof (obj_type), ((uintptr_t)obj_addr)) \
    != sizeof (obj_type)) { \
        mdb_warn("error reading "#obj_type" at %p", obj_addr); \
        return (err); \
    }

/*
 * We need to read in a private copy
 * of every string we want to print out.
 */
void
print_str(uintptr_t addr)
{
    char buf[64];
    int len, mx = sizeof (buf) - 4;

    if ((len = mdb_readstr(buf, sizeof (buf), addr)) <= 0) {
        mdb_printf(" (%p)", addr);
    } else {
        if (len > mx)
            strcpy(&buf[mx], "...");
        mdb_printf(" %s", buf);
    }
}

/*
 * Dcmd (and callback function) to print a summary of
 * all "smbfs" entries in the VFS list.
 */

typedef struct smbfs_vfs_cbdata {
    int flags;
    int printed_header;
    uintptr_t vfsops;   /* filter by vfs ops pointer */
    smbmntinfo_t smi;   /* scratch space for smbfs_vfs_cb */
} smbfs_vfs_cbdata_t;

int
smbfs_vfs_cb(uintptr_t addr, const void *data, void *arg)
{
    const vfs_t *vfs = data;
    smbfs_vfs_cbdata_t *cbd = arg;
    uintptr_t ta;

    /* Filter by matching smbfs ops vector. */
    if (cbd->vfsops && cbd->vfsops != (uintptr_t)vfs->vfs_op) {
        return (WALK_NEXT);
    }

    if (cbd->printed_header == 0) {
        cbd->printed_header = 1;
        mdb_printf("// vfs_t smbmntinfo_t mnt_path\n");
    }

    mdb_printf(" %-p", addr);   /* vfs_t */
    mdb_printf(" %-p", (uintptr_t)vfs->vfs_data);
    /*
     * Note: vfs_mntpt is a refstr_t.
     * Advance to string member.
     */
    ta = (uintptr_t)vfs->vfs_mntpt;
    ta += OFFSETOF(struct refstr, rs_string);
    print_str(ta);
    mdb_printf("\n");

    if (cbd->flags & OPT_VERBOSE) {
        mdb_inc_indent(2);
        /* Don't fail the walk if this fails. */
        if (mdb_vread(&cbd->smi, sizeof (cbd->smi),
            (uintptr_t)vfs->vfs_data) == -1) {
            mdb_warn("error reading smbmntinfo_t at %p",
                (uintptr_t)vfs->vfs_data);
        } else {
            /* Interesting parts of smbmntinfo_t */
            mdb_printf("smi_share: %p, smi_root: %p\n",
                cbd->smi.smi_share, cbd->smi.smi_root);
        }
        mdb_dec_indent(2);
    }

    return (WALK_NEXT);
}

int
smbfs_vfs_dcmd(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    smbfs_vfs_cbdata_t *cbd;
    vfs_t *vfs;

    cbd = mdb_zalloc(sizeof (*cbd),  UM_SLEEP | UM_GC);

    /*
     * Get the ops address here, so things work
     * even if the smbfs module is loaded later
     * than this mdb module.
     */
    if (mdb_readvar(&cbd->vfsops, "smbfs_vfsops") == -1) {
        mdb_warn("failed to find 'smbfs_vfsops'\n");
        return (DCMD_ERR);
    }

    if (mdb_getopts(argc, argv,
        'v', MDB_OPT_SETBITS, OPT_VERBOSE, &cbd->flags,
        NULL) != argc) {
        return (DCMD_USAGE);
    }

    if (!(flags & DCMD_ADDRSPEC)) {
        if (mdb_walk("genunix`vfs", smbfs_vfs_cb, cbd)
            == -1) {
            mdb_warn("can't walk smbfs vfs");
            return (DCMD_ERR);
        }
        return (DCMD_OK);
    }

    vfs = mdb_alloc(sizeof (*vfs),  UM_SLEEP | UM_GC);
    SMBFS_OBJ_FETCH(addr, vfs_t, vfs, DCMD_ERR);
    smbfs_vfs_cb(addr, vfs, cbd);
    return (DCMD_OK);
}

void
smbfs_vfs_help(void)
{
    mdb_printf(
        "Display addresses of the mounted smbfs structures\n"
        "and the pathname of the mountpoint\n"
        "\nOptions:\n"
        "  -v    display details of the smbmntinfo\n");
}

/*
 * Dcmd (and callback function) to print a summary of
 * all smbnodes in the node "hash" (cache) AVL tree.
 */

typedef struct smbfs_node_cbdata {
    int flags;
    int printed_header;
    vnode_t vn;
} smbfs_node_cbdata_t;

int
smbfs_node_cb(uintptr_t addr, const void *data, void *arg)
{
    const smbnode_t *np = data;
    smbfs_node_cbdata_t *cbd = arg;

    if (cbd->printed_header == 0) {
        cbd->printed_header = 1;
        mdb_printf("// vnode smbnode rpath\n");
    }

    mdb_printf(" %-p", (uintptr_t)np->r_vnode);
    mdb_printf(" %-p", addr);   /* smbnode */
    print_str((uintptr_t)np->n_rpath);
    mdb_printf("\n");

    if (cbd->flags & OPT_VERBOSE) {
        mdb_inc_indent(2);
        /* Don't fail the walk if this fails. */
        if (mdb_vread(&cbd->vn, sizeof (cbd->vn),
            (uintptr_t)np->r_vnode) == -1) {
            mdb_warn("error reading vnode_t at %p",
                (uintptr_t)np->r_vnode);
        } else {
            /* Interesting parts of vnode_t */
            mdb_printf("v_type=%d v_count=%d",
                cbd->vn.v_type, cbd->vn.v_count);
            mdb_printf("\n");
        }
        mdb_dec_indent(2);
    }

    return (WALK_NEXT);
}

int
smbfs_node_dcmd(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    smbfs_node_cbdata_t *cbd;

    cbd = mdb_zalloc(sizeof (*cbd), UM_SLEEP | UM_GC);

    if (mdb_getopts(argc, argv,
        'v', MDB_OPT_SETBITS, OPT_VERBOSE, &cbd->flags,
        NULL) != argc) {
        return (DCMD_USAGE);
    }

    if (!(flags & DCMD_ADDRSPEC)) {
        mdb_warn("expect an smbmntinfo_t addr");
        return (DCMD_USAGE);
    }
    addr += OFFSETOF(smbmntinfo_t, smi_hash_avl);

    if (mdb_pwalk("genunix`avl", smbfs_node_cb, cbd, addr) == -1) {
        mdb_warn("cannot walk smbfs nodes");
        return (DCMD_ERR);
    }

    return (DCMD_OK);
}

void
smbfs_node_help(void)
{
    mdb_printf("Options:\n"
        "  -v           be verbose when displaying smbnodes\n");
}

static const mdb_dcmd_t dcmds[] = {
    {
        "smbfs_vfs", "?[-v]",
        "show smbfs-mounted vfs structs",
        smbfs_vfs_dcmd, smbfs_vfs_help
    },
    {
        "smbfs_node", "?[-v]",
        "given an smbmntinfo_t, list smbnodes",
        smbfs_node_dcmd, smbfs_node_help
    },
    {NULL}
};

static const mdb_walker_t walkers[] = {
    {NULL}
};

static const mdb_modinfo_t modinfo = {
    MDB_API_VERSION,
    dcmds,
    walkers
};

const mdb_modinfo_t *
_mdb_init(void)
{
    return (&modinfo);
}