modules/mdb_ds/mdb_ds.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * MDB developer support module.  This module is loaded automatically when the
 * proc target is initialized and the target is mdb itself.  In the future, we
 * should document these facilities in the answerbook to aid module developers.
 */

#define _MDB
#include <mdb/mdb_modapi.h>
#include <mdb/mdb_frame.h>
#include <mdb/mdb_io_impl.h>
#include <mdb/mdb_target_impl.h>
#include <kmdb/kmdb_wr_impl.h>
#include <mdb/mdb.h>

static const mdb_t *
get_mdb(void)
{
    static mdb_t m;

    if (mdb_readvar(&m, "mdb") == -1)
        mdb_warn("failed to read mdb_t state");

    return (&m);
}

static int
cmd_stack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    const char sep[] =
        "-----------------------------------------------------------------";

    if (flags & DCMD_ADDRSPEC) {
        char buf[MDB_NV_NAMELEN + 1];
        uintptr_t sp, pc;
        mdb_idcmd_t idc;
        mdb_frame_t f;
        mdb_cmd_t c;
        mdb_arg_t *ap;
        size_t i;

        if (mdb_vread(&f, sizeof (f), addr) == -1) {
            mdb_warn("failed to read frame at %p", addr);
            return (DCMD_ERR);
        }

        bzero(&c, sizeof (mdb_cmd_t));

        if (mdb_vread(&c, sizeof (c), (uintptr_t)f.f_cp) < 0 ||
            mdb_vread(&idc, sizeof (idc), (uintptr_t)c.c_dcmd) < 0 ||
            mdb_readstr(buf, sizeof (buf), (uintptr_t)idc.idc_name) < 1)
            (void) strcpy(buf, "?");

        mdb_printf("+>\tframe <%u> %p (%s", f.f_id, addr, buf);
        ap = mdb_alloc(c.c_argv.a_nelems * sizeof (mdb_arg_t), UM_GC);

        if (ap != NULL && mdb_vread(ap, c.c_argv.a_nelems *
            sizeof (mdb_arg_t), (uintptr_t)c.c_argv.a_data) > 0) {
            for (i = 0; i < c.c_argv.a_nelems; i++) {
                switch (ap[i].a_type) {
                case MDB_TYPE_STRING:
                    if (mdb_readstr(buf, sizeof (buf),
                        (uintptr_t)ap[i].a_un.a_str) > 0)
                        mdb_printf(" %s", buf);
                    else
                        mdb_printf(" <str=%a>",
                            ap[i].a_un.a_str);
                    break;
                case MDB_TYPE_IMMEDIATE:
                    mdb_printf(" $[ 0x%llx ]",
                        ap[i].a_un.a_val);
                    break;
                case MDB_TYPE_CHAR:
                    mdb_printf(" '%c'", ap[i].a_un.a_char);
                    break;
                default:
                    mdb_printf(" <type=%d>", ap[i].a_type);
                }
            }
        }

        mdb_printf(")\n\tf_list = %-?p\tf_cmds = %p\n",
            addr + OFFSETOF(mdb_frame_t, f_list),
            addr + OFFSETOF(mdb_frame_t, f_cmds));
        mdb_printf("\tf_istk = %-?p\tf_ostk = %p\n",
            addr + OFFSETOF(mdb_frame_t, f_istk),
            addr + OFFSETOF(mdb_frame_t, f_ostk));
        mdb_printf("\tf_wcbs = %-?p\tf_mblks = %p\n",
            f.f_wcbs, f.f_mblks);
        mdb_printf("\tf_pcmd = %-?p\tf_pcb = %p\n",
            f.f_pcmd, addr + OFFSETOF(mdb_frame_t, f_pcb));
        mdb_printf("\tf_cp = %-?p\t\tf_flags = 0x%x\n\n",
            f.f_cp, f.f_flags);

#if defined(__sparc)
        sp = ((uintptr_t *)f.f_pcb)[1];
        pc = ((uintptr_t *)f.f_pcb)[2];
#elif defined(__amd64)
        sp = ((uintptr_t *)f.f_pcb)[5];
        pc = ((uintptr_t *)f.f_pcb)[7];
#elif defined(__i386)
        sp = ((uintptr_t *)f.f_pcb)[3];
        pc = ((uintptr_t *)f.f_pcb)[5];
#else
#error  Unknown ISA
#endif
        if (pc != 0)
            mdb_printf("      [ %0?lr %a() ]\n", sp, pc);

        mdb_set_dot(sp);
        mdb_inc_indent(8);
        mdb_eval("<.$C0");
        mdb_dec_indent(8);
        mdb_printf("%s\n", sep);

    } else {
        mdb_printf("%s\n", sep);
        (void) mdb_walk_dcmd("mdb_frame", "mdb_stack", argc, argv);
    }

    return (DCMD_OK);
}

static int
cmd_frame(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    if ((flags & DCMD_ADDRSPEC) && argc == 0)
        return (cmd_stack(addr, flags, argc, argv));

    return (DCMD_USAGE);
}

/*ARGSUSED*/
static int
cmd_iob(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    mdb_iob_t iob;
    mdb_io_t io;

    if (!(flags & DCMD_ADDRSPEC) || argc != 0)
        return (DCMD_USAGE);

    if (DCMD_HDRSPEC(flags)) {
        mdb_printf("%?s %6s %6s %?s %s\n",
            "IOB", "NBYTES", "FLAGS", "IOP", "OPS");
    }

    if (mdb_vread(&iob, sizeof (iob), addr) == -1 ||
        mdb_vread(&io, sizeof (io), (uintptr_t)iob.iob_iop) == -1) {
        mdb_warn("failed to read iob at %p", addr);
        return (DCMD_ERR);
    }

    mdb_printf("%?p %6lu %6x %?p %a\n", addr, (ulong_t)iob.iob_nbytes,
        iob.iob_flags, iob.iob_iop, io.io_ops);

    return (DCMD_OK);
}

/*ARGSUSED*/
static int
cmd_in(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    mdb_printf("%p\n", get_mdb()->m_in);
    return (DCMD_OK);
}

/*ARGSUSED*/
static int
cmd_out(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    mdb_printf("%p\n", get_mdb()->m_out);
    return (DCMD_OK);
}

/*ARGSUSED*/
static int
cmd_err(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    mdb_printf("%p\n", get_mdb()->m_err);
    return (DCMD_OK);
}

/*ARGSUSED*/
static int
cmd_target(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    mdb_tgt_t t;

    if (argc != 0)
        return (DCMD_USAGE);

    if (!(flags & DCMD_ADDRSPEC))
        addr = (uintptr_t)get_mdb()->m_target;

    if (mdb_vread(&t, sizeof (t), addr) != sizeof (t)) {
        mdb_warn("failed to read target at %p", addr);
        return (DCMD_ERR);
    }

    mdb_printf("+>\ttarget %p (%a)\n", addr, t.t_ops);

    mdb_printf("\tt_active = %-?p\tt_idle = %p\n",
        addr + OFFSETOF(mdb_tgt_t, t_active),
        addr + OFFSETOF(mdb_tgt_t, t_idle));
    mdb_printf("\tt_xdlist = %-?p\tt_module = %a\n",
        addr + OFFSETOF(mdb_tgt_t, t_xdlist), t.t_module);
    mdb_printf("\tt_pshandle = %-?p\tt_data = %p\n",
        t.t_pshandle, t.t_data);
    mdb_printf("\tt_status = %-?p\tt_matched = %p\n",
        addr + OFFSETOF(mdb_tgt_t, t_status), t.t_matched);
    mdb_printf("\tt_flags = %-?x\tt_vecnt = 0t%u\n", t.t_flags, t.t_vecnt);
    mdb_printf("\tt_vepos = %-?d\tt_veneg = %d\n\n", t.t_vepos, t.t_veneg);

    return (DCMD_OK);
}

/*ARGSUSED*/
static int
cmd_sespec(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    mdb_sespec_t se;

    if (argc != 0 || !(flags & DCMD_ADDRSPEC))
        return (DCMD_USAGE);

    if (mdb_vread(&se, sizeof (se), addr) != sizeof (se)) {
        mdb_warn("failed to read sespec at %p", addr);
        return (DCMD_ERR);
    }

    mdb_printf("+>\tsespec %p (%a)\n", addr, se.se_ops);

    mdb_printf("\tse_selist = %-?p\tse_velist = %p\n",
        addr + OFFSETOF(mdb_sespec_t, se_selist),
        addr + OFFSETOF(mdb_sespec_t, se_velist));

    mdb_printf("\tse_data = %-?p\tse_refs = %u\n",
        se.se_data, se.se_refs);
    mdb_printf("\tse_state = %-?d\tse_errno = %d\n\n",
        se.se_state, se.se_errno);

    return (DCMD_OK);
}

/*ARGSUSED*/
static int
cmd_vespec(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    mdb_vespec_t ve;

    if (argc != 0 || !(flags & DCMD_ADDRSPEC))
        return (DCMD_USAGE);

    if (mdb_vread(&ve, sizeof (ve), addr) != sizeof (ve)) {
        mdb_warn("failed to read vespec at %p", addr);
        return (DCMD_ERR);
    }

    mdb_printf("+>\tvespec %p (id %d)\n", addr, ve.ve_id);
    mdb_printf("\tve_list = %-?p\tve_flags = 0x%x\n",
        addr + OFFSETOF(mdb_vespec_t, ve_list), ve.ve_flags);
    mdb_printf("\tve_se = %-?p\tve_refs = %u\n", ve.ve_se, ve.ve_refs);
    mdb_printf("\tve_hits = %-?u\tve_lim = %u\n", ve.ve_hits, ve.ve_limit);
    mdb_printf("\tve_data = %-?p\tve_callback = %a\n",
        ve.ve_data, ve.ve_callback);
    mdb_printf("\tve_args = %-?p\tve_dtor = %a\n\n",
        ve.ve_args, ve.ve_dtor);

    return (DCMD_OK);
}

/*ARGSUSED*/
static int
cmd_wr(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
    char path[MAXPATHLEN];
    kmdb_wr_t wn;
    char dir;

    if (argc != 0 || !(flags & DCMD_ADDRSPEC))
        return (DCMD_USAGE);

    if (mdb_vread(&wn, sizeof (wn), addr) != sizeof (wn)) {
        mdb_warn("failed to read wr node at %p", addr);
        return (DCMD_ERR);
    }

    if (DCMD_HDRSPEC(flags)) {
        mdb_printf("%-9s %3s %?s %s\n",
            "COMMAND", "ERR", "MODCTL", "NAME");
    }

    dir = "><"[WR_ISACK(&wn) != 0];
    switch (WR_TASK(&wn)) {
    case WNTASK_DMOD_LOAD: {
        kmdb_wr_load_t dlr;

        if (mdb_vread(&dlr, sizeof (dlr), addr) != sizeof (dlr)) {
            mdb_warn("failed to read kmdb_wr_load_t at %p", addr);
            return (DCMD_ERR);
        }

        if (mdb_readstr(path, sizeof (path),
            (uintptr_t)dlr.dlr_fname) < 0) {
            mdb_warn("failed to read path name at %p",
                dlr.dlr_fname);
            *path = '\0';
        }

        mdb_printf("%cload     %3d %?p %s\n", dir, dlr.dlr_errno,
            dlr.dlr_modctl, path);
        break;
    }

    case WNTASK_DMOD_LOAD_ALL:
        mdb_printf("%cload all %3d\n", dir, wn.wn_errno);
        break;

    case WNTASK_DMOD_UNLOAD: {
        kmdb_wr_unload_t dur;

        if (mdb_vread(&dur, sizeof (dur), addr) != sizeof (dur)) {
            mdb_warn("failed to read kmdb_wr_unload_t at %p", addr);
            return (DCMD_ERR);
        }

        if (mdb_readstr(path, sizeof (path),
            (uintptr_t)dur.dur_modname) < 0) {
            mdb_warn("failed to read module name at %p",
                dur.dur_modname);
            *path = '\0';
        }

        mdb_printf("%cunload   %3d %?p %s\n", dir, dur.dur_errno,
            dur.dur_modctl, path);
        break;
    }

    case WNTASK_DMOD_PATH_CHANGE: {
        kmdb_wr_path_t dpth;
        uintptr_t pathp;
        int first = 1;

        if (mdb_vread(&dpth, sizeof (dpth), addr) != sizeof (dpth)) {
            mdb_warn("failed to read kmdb_wr_path_t at %p", addr);
            return (DCMD_ERR);
        }

        mdb_printf("%cpath chg %3d ", dir, dpth.dpth_errno);
        for (;;) {
            if (mdb_vread(&pathp, sizeof (pathp),
                (uintptr_t)dpth.dpth_path) != sizeof (pathp)) {
                mdb_warn("failed to read path pointer at %p",
                    dpth.dpth_path);
                break;
            }

            dpth.dpth_path++;

            if (pathp == NULL)
                break;

            if (mdb_readstr(path, sizeof (path), pathp) < 0) {
                mdb_warn("failed to read path at %p", pathp);
                *path = '\0';
            }

            mdb_printf("%s%s", (first ? "" : "\n             "),
                path);
            first = 0;
        }
        mdb_printf("\n");
        break;
    }

    default:
        mdb_warn("unknown task type %d\n", wn.wn_task);
        return (DCMD_ERR);
    }

    return (DCMD_OK);
}

static int
iob_stack_walk_init(mdb_walk_state_t *wsp)
{
    mdb_iob_stack_t stk;

    if (mdb_vread(&stk, sizeof (stk), wsp->walk_addr) == -1) {
        mdb_warn("failed to read iob_stack at %p", wsp->walk_addr);
        return (WALK_ERR);
    }

    wsp->walk_addr = (uintptr_t)stk.stk_top;
    return (WALK_NEXT);
}

static int
iob_stack_walk_step(mdb_walk_state_t *wsp)
{
    uintptr_t addr = wsp->walk_addr;
    mdb_iob_t iob;

    if (addr == NULL)
        return (WALK_DONE);

    if (mdb_vread(&iob, sizeof (iob), addr) == -1) {
        mdb_warn("failed to read iob at %p", addr);
        return (WALK_ERR);
    }

    wsp->walk_addr = (uintptr_t)iob.iob_next;
    return (wsp->walk_callback(addr, &iob, wsp->walk_cbdata));
}

static int
frame_walk_init(mdb_walk_state_t *wsp)
{
    if (wsp->walk_addr == NULL)
        wsp->walk_addr = (uintptr_t)get_mdb()->m_flist.ml_prev;

    return (WALK_NEXT);
}

static int
frame_walk_step(mdb_walk_state_t *wsp)
{
    uintptr_t addr = wsp->walk_addr;
    mdb_frame_t f;

    if (addr == NULL)
        return (WALK_DONE);

    if (mdb_vread(&f, sizeof (f), addr) == -1) {
        mdb_warn("failed to read frame at %p", addr);
        return (WALK_ERR);
    }

    wsp->walk_addr = (uintptr_t)f.f_list.ml_prev;
    return (wsp->walk_callback(addr, &f, wsp->walk_cbdata));
}

static int
target_walk_init(mdb_walk_state_t *wsp)
{
    if (wsp->walk_addr == NULL)
        wsp->walk_addr = (uintptr_t)get_mdb()->m_target;

    return (WALK_NEXT);
}

static int
target_walk_step(mdb_walk_state_t *wsp)
{
    uintptr_t addr = wsp->walk_addr;
    mdb_tgt_t t;

    if (addr == NULL)
        return (WALK_DONE);

    if (mdb_vread(&t, sizeof (t), addr) == -1) {
        mdb_warn("failed to read target at %p", addr);
        return (WALK_ERR);
    }

    wsp->walk_addr = (uintptr_t)t.t_tgtlist.ml_next;
    return (wsp->walk_callback(addr, &t, wsp->walk_cbdata));
}

static int
sespec_walk_step(mdb_walk_state_t *wsp)
{
    uintptr_t addr = wsp->walk_addr;
    mdb_sespec_t s;

    if (addr == NULL)
        return (WALK_DONE);

    if (mdb_vread(&s, sizeof (s), addr) == -1) {
        mdb_warn("failed to read sespec at %p", addr);
        return (WALK_ERR);
    }

    wsp->walk_addr = (uintptr_t)s.se_selist.ml_next;
    return (wsp->walk_callback(addr, &s, wsp->walk_cbdata));
}

static int
vespec_walk_step(mdb_walk_state_t *wsp)
{
    uintptr_t addr = wsp->walk_addr;
    mdb_vespec_t v;

    if (addr == NULL)
        return (WALK_DONE);

    if (mdb_vread(&v, sizeof (v), addr) == -1) {
        mdb_warn("failed to read vespec at %p", addr);
        return (WALK_ERR);
    }

    wsp->walk_addr = (uintptr_t)v.ve_list.ml_next;
    return (wsp->walk_callback(addr, &v, wsp->walk_cbdata));
}

static int
se_matched_walk_step(mdb_walk_state_t *wsp)
{
    uintptr_t addr = wsp->walk_addr;
    mdb_sespec_t s;

    if (addr == NULL)
        return (WALK_DONE);

    if (mdb_vread(&s, sizeof (s), addr) == -1) {
        mdb_warn("failed to read sespec at %p", addr);
        return (WALK_ERR);
    }

    wsp->walk_addr = (uintptr_t)s.se_matched;
    return (wsp->walk_callback(addr, &s, wsp->walk_cbdata));
}

static const mdb_dcmd_t dcmds[] = {
    { "mdb_stack", "?", "print debugger stack", cmd_stack },
    { "mdb_frame", ":", "print debugger frame", cmd_frame },
    { "mdb_iob", ":", "print i/o buffer information", cmd_iob },
    { "mdb_in", NULL, "print stdin iob", cmd_in },
    { "mdb_out", NULL, "print stdout iob", cmd_out },
    { "mdb_err", NULL, "print stderr iob", cmd_err },
    { "mdb_tgt", "?", "print current target", cmd_target },
    { "mdb_sespec", ":", "print software event specifier", cmd_sespec },
    { "mdb_vespec", ":", "print virtual event specifier", cmd_vespec },
    { "kmdb_wr", NULL, "print a work queue entry", cmd_wr },
    { NULL }
};

static const mdb_walker_t walkers[] = {
    { "mdb_frame", "iterate over mdb_frame stack",
        frame_walk_init, frame_walk_step, NULL },
    { "mdb_iob_stack", "iterate over mdb_iob_stack elements",
        iob_stack_walk_init, iob_stack_walk_step, NULL },
    { "mdb_tgt", "iterate over active targets",
        target_walk_init, target_walk_step, NULL },
    { "mdb_sespec", "iterate over software event specifiers",
        NULL, sespec_walk_step, NULL },
    { "mdb_vespec", "iterate over virtual event specifiers",
        NULL, vespec_walk_step, NULL },
    { "se_matched", "iterate over matched software event specifiers",
        NULL, se_matched_walk_step, NULL },
    { NULL }
};

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

const mdb_modinfo_t *
_mdb_init(void)
{
    char buf[256];
    uintptr_t addr;
    int rcount;
    GElf_Sym sym;

    if (mdb_lookup_by_name("mdb", &sym) == -1) {
        mdb_warn("failed to read mdb state structure");
        return (NULL);
    }

    if (sym.st_size != sizeof (mdb_t)) {
        mdb_printf("mdb: WARNING: mdb_ds may not match mdb "
            "implementation (mdb_t mismatch)\n");
    }

    if (mdb_readvar(&addr, "_mdb_abort_str") != -1 && addr != NULL &&
        mdb_readstr(buf, sizeof (buf), addr) > 0)
        mdb_printf("mdb: debugger failed with error: %s\n", buf);

    if (mdb_readvar(&rcount, "_mdb_abort_rcount") != -1 && rcount != 0)
        mdb_printf("mdb: WARNING: resume executed %d times\n", rcount);

    return (&modinfo);
}