8158 Want named threads API

[unleashed.git] / usr / src / lib / libdtrace / common / dt_dof.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) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright (c) 2011 by Delphix. All rights reserved.
 * Copyright (c) 2013, Joyent, Inc. All rights reserved.
 */

#include <sys/types.h>
#include <sys/sysmacros.h>

#include <strings.h>
#include <alloca.h>
#include <assert.h>
#include <stdlib.h>
#include <errno.h>
#include <limits.h>

#include <dt_impl.h>
#include <dt_strtab.h>
#include <dt_program.h>
#include <dt_provider.h>
#include <dt_xlator.h>
#include <dt_dof.h>

void
dt_dof_init(dtrace_hdl_t *dtp)
{
        dt_dof_t *ddo = &dtp->dt_dof;

        ddo->ddo_hdl = dtp;
        ddo->ddo_nsecs = 0;
        ddo->ddo_strsec = DOF_SECIDX_NONE;
        ddo->ddo_xlimport = NULL;
        ddo->ddo_xlexport = NULL;

        dt_buf_create(dtp, &ddo->ddo_secs, "section headers", 0);
        dt_buf_create(dtp, &ddo->ddo_strs, "string table", 0);
        dt_buf_create(dtp, &ddo->ddo_ldata, "loadable data", 0);
        dt_buf_create(dtp, &ddo->ddo_udata, "unloadable data", 0);

        dt_buf_create(dtp, &ddo->ddo_probes, "probe data", 0);
        dt_buf_create(dtp, &ddo->ddo_args, "probe args", 0);
        dt_buf_create(dtp, &ddo->ddo_offs, "probe offs", 0);
        dt_buf_create(dtp, &ddo->ddo_enoffs, "probe is-enabled offs", 0);
        dt_buf_create(dtp, &ddo->ddo_rels, "probe rels", 0);

        dt_buf_create(dtp, &ddo->ddo_xlms, "xlate members", 0);
}

void
dt_dof_fini(dtrace_hdl_t *dtp)
{
        dt_dof_t *ddo = &dtp->dt_dof;

        dt_free(dtp, ddo->ddo_xlimport);
        dt_free(dtp, ddo->ddo_xlexport);

        dt_buf_destroy(dtp, &ddo->ddo_secs);
        dt_buf_destroy(dtp, &ddo->ddo_strs);
        dt_buf_destroy(dtp, &ddo->ddo_ldata);
        dt_buf_destroy(dtp, &ddo->ddo_udata);

        dt_buf_destroy(dtp, &ddo->ddo_probes);
        dt_buf_destroy(dtp, &ddo->ddo_args);
        dt_buf_destroy(dtp, &ddo->ddo_offs);
        dt_buf_destroy(dtp, &ddo->ddo_enoffs);
        dt_buf_destroy(dtp, &ddo->ddo_rels);

        dt_buf_destroy(dtp, &ddo->ddo_xlms);
}

static int
dt_dof_reset(dtrace_hdl_t *dtp, dtrace_prog_t *pgp)
{
        dt_dof_t *ddo = &dtp->dt_dof;
        uint_t i, nx = dtp->dt_xlatorid;

        assert(ddo->ddo_hdl == dtp);
        ddo->ddo_pgp = pgp;

        ddo->ddo_nsecs = 0;
        ddo->ddo_strsec = DOF_SECIDX_NONE;

        dt_free(dtp, ddo->ddo_xlimport);
        dt_free(dtp, ddo->ddo_xlexport);

        ddo->ddo_xlimport = dt_alloc(dtp, sizeof (dof_secidx_t) * nx);
        ddo->ddo_xlexport = dt_alloc(dtp, sizeof (dof_secidx_t) * nx);

        if (nx != 0 && (ddo->ddo_xlimport == NULL || ddo->ddo_xlexport == NULL))
                return (-1); /* errno is set for us */

        for (i = 0; i < nx; i++) {
                ddo->ddo_xlimport[i] = DOF_SECIDX_NONE;
                ddo->ddo_xlexport[i] = DOF_SECIDX_NONE;
        }

        dt_buf_reset(dtp, &ddo->ddo_secs);
        dt_buf_reset(dtp, &ddo->ddo_strs);
        dt_buf_reset(dtp, &ddo->ddo_ldata);
        dt_buf_reset(dtp, &ddo->ddo_udata);

        dt_buf_reset(dtp, &ddo->ddo_probes);
        dt_buf_reset(dtp, &ddo->ddo_args);
        dt_buf_reset(dtp, &ddo->ddo_offs);
        dt_buf_reset(dtp, &ddo->ddo_enoffs);
        dt_buf_reset(dtp, &ddo->ddo_rels);

        dt_buf_reset(dtp, &ddo->ddo_xlms);
        return (0);
}

/*
 * Add a loadable DOF section to the file using the specified data buffer and
 * the specified DOF section attributes.  DOF_SECF_LOAD must be set in flags.
 * If 'data' is NULL, the caller is responsible for manipulating the ldata buf.
 */
static dof_secidx_t
dof_add_lsect(dt_dof_t *ddo, const void *data, uint32_t type,
    uint32_t align, uint32_t flags, uint32_t entsize, uint64_t size)
{
        dtrace_hdl_t *dtp = ddo->ddo_hdl;
        dof_sec_t s;

        s.dofs_type = type;
        s.dofs_align = align;
        s.dofs_flags = flags | DOF_SECF_LOAD;
        s.dofs_entsize = entsize;
        s.dofs_offset = dt_buf_offset(&ddo->ddo_ldata, align);
        s.dofs_size = size;

        dt_buf_write(dtp, &ddo->ddo_secs, &s, sizeof (s), sizeof (uint64_t));

        if (data != NULL)
                dt_buf_write(dtp, &ddo->ddo_ldata, data, size, align);

        return (ddo->ddo_nsecs++);
}

/*
 * Add an unloadable DOF section to the file using the specified data buffer
 * and DOF section attributes.  DOF_SECF_LOAD must *not* be set in flags.
 * If 'data' is NULL, the caller is responsible for manipulating the udata buf.
 */
static dof_secidx_t
dof_add_usect(dt_dof_t *ddo, const void *data, uint32_t type,
    uint32_t align, uint32_t flags, uint32_t entsize, uint64_t size)
{
        dtrace_hdl_t *dtp = ddo->ddo_hdl;
        dof_sec_t s;

        s.dofs_type = type;
        s.dofs_align = align;
        s.dofs_flags = flags & ~DOF_SECF_LOAD;
        s.dofs_entsize = entsize;
        s.dofs_offset = dt_buf_offset(&ddo->ddo_udata, align);
        s.dofs_size = size;

        dt_buf_write(dtp, &ddo->ddo_secs, &s, sizeof (s), sizeof (uint64_t));

        if (data != NULL)
                dt_buf_write(dtp, &ddo->ddo_udata, data, size, align);

        return (ddo->ddo_nsecs++);
}

/*
 * Add a string to the global string table associated with the DOF.  The offset
 * of the string is returned as an index into the string table.
 */
static dof_stridx_t
dof_add_string(dt_dof_t *ddo, const char *s)
{
        dt_buf_t *bp = &ddo->ddo_strs;
        dof_stridx_t i = dt_buf_len(bp);

        if (i != 0 && (s == NULL || *s == '\0'))
                return (0); /* string table has \0 at offset 0 */

        dt_buf_write(ddo->ddo_hdl, bp, s, strlen(s) + 1, sizeof (char));
        return (i);
}

static dof_attr_t
dof_attr(const dtrace_attribute_t *ap)
{
        return (DOF_ATTR(ap->dtat_name, ap->dtat_data, ap->dtat_class));
}

static dof_secidx_t
dof_add_difo(dt_dof_t *ddo, const dtrace_difo_t *dp)
{
        dof_secidx_t dsecs[5]; /* enough for all possible DIFO sections */
        uint_t nsecs = 0;

        dof_difohdr_t *dofd;
        dof_relohdr_t dofr;
        dof_secidx_t relsec;

        dof_secidx_t strsec = DOF_SECIDX_NONE;
        dof_secidx_t intsec = DOF_SECIDX_NONE;
        dof_secidx_t hdrsec = DOF_SECIDX_NONE;

        if (dp->dtdo_buf != NULL) {
                dsecs[nsecs++] = dof_add_lsect(ddo, dp->dtdo_buf,
                    DOF_SECT_DIF, sizeof (dif_instr_t), 0,
                    sizeof (dif_instr_t), sizeof (dif_instr_t) * dp->dtdo_len);
        }

        if (dp->dtdo_inttab != NULL) {
                dsecs[nsecs++] = intsec = dof_add_lsect(ddo, dp->dtdo_inttab,
                    DOF_SECT_INTTAB, sizeof (uint64_t), 0,
                    sizeof (uint64_t), sizeof (uint64_t) * dp->dtdo_intlen);
        }

        if (dp->dtdo_strtab != NULL) {
                dsecs[nsecs++] = strsec = dof_add_lsect(ddo, dp->dtdo_strtab,
                    DOF_SECT_STRTAB, sizeof (char), 0, 0, dp->dtdo_strlen);
        }

        if (dp->dtdo_vartab != NULL) {
                dsecs[nsecs++] = dof_add_lsect(ddo, dp->dtdo_vartab,
                    DOF_SECT_VARTAB, sizeof (uint_t), 0, sizeof (dtrace_difv_t),
                    sizeof (dtrace_difv_t) * dp->dtdo_varlen);
        }

        if (dp->dtdo_xlmtab != NULL) {
                dof_xlref_t *xlt, *xlp;
                dt_node_t **pnp;

                xlt = alloca(sizeof (dof_xlref_t) * dp->dtdo_xlmlen);
                pnp = dp->dtdo_xlmtab;

                /*
                 * dtdo_xlmtab contains pointers to the translator members.
                 * The translator itself is in sect ddo_xlimport[dxp->dx_id].
                 * The XLMEMBERS entries are in order by their dn_membid, so
                 * the member section offset is the population count of bits
                 * in ddo_pgp->dp_xlrefs[] up to and not including dn_membid.
                 */
                for (xlp = xlt; xlp < xlt + dp->dtdo_xlmlen; xlp++) {
                        dt_node_t *dnp = *pnp++;
                        dt_xlator_t *dxp = dnp->dn_membexpr->dn_xlator;

                        xlp->dofxr_xlator = ddo->ddo_xlimport[dxp->dx_id];
                        xlp->dofxr_member = dt_popcb(
                            ddo->ddo_pgp->dp_xrefs[dxp->dx_id], dnp->dn_membid);
                        xlp->dofxr_argn = (uint32_t)dxp->dx_arg;
                }

                dsecs[nsecs++] = dof_add_lsect(ddo, xlt, DOF_SECT_XLTAB,
                    sizeof (dof_secidx_t), 0, sizeof (dof_xlref_t),
                    sizeof (dof_xlref_t) * dp->dtdo_xlmlen);
        }

        /*
         * Copy the return type and the array of section indices that form the
         * DIFO into a single dof_difohdr_t and then add DOF_SECT_DIFOHDR.
         */
        assert(nsecs <= sizeof (dsecs) / sizeof (dsecs[0]));
        dofd = alloca(sizeof (dtrace_diftype_t) + sizeof (dsecs));
        bcopy(&dp->dtdo_rtype, &dofd->dofd_rtype, sizeof (dtrace_diftype_t));
        bcopy(dsecs, &dofd->dofd_links, sizeof (dof_secidx_t) * nsecs);

        hdrsec = dof_add_lsect(ddo, dofd, DOF_SECT_DIFOHDR,
            sizeof (dof_secidx_t), 0, 0,
            sizeof (dtrace_diftype_t) + sizeof (dof_secidx_t) * nsecs);

        /*
         * Add any other sections related to dtrace_difo_t.  These are not
         * referenced in dof_difohdr_t because they are not used by emulation.
         */
        if (dp->dtdo_kreltab != NULL) {
                relsec = dof_add_lsect(ddo, dp->dtdo_kreltab, DOF_SECT_RELTAB,
                    sizeof (uint64_t), 0, sizeof (dof_relodesc_t),
                    sizeof (dof_relodesc_t) * dp->dtdo_krelen);

                /*
                 * This code assumes the target of all relocations is the
                 * integer table 'intsec' (DOF_SECT_INTTAB).  If other sections
                 * need relocation in the future this will need to change.
                 */
                dofr.dofr_strtab = strsec;
                dofr.dofr_relsec = relsec;
                dofr.dofr_tgtsec = intsec;

                (void) dof_add_lsect(ddo, &dofr, DOF_SECT_KRELHDR,
                    sizeof (dof_secidx_t), 0, 0, sizeof (dof_relohdr_t));
        }

        if (dp->dtdo_ureltab != NULL) {
                relsec = dof_add_lsect(ddo, dp->dtdo_ureltab, DOF_SECT_RELTAB,
                    sizeof (uint64_t), 0, sizeof (dof_relodesc_t),
                    sizeof (dof_relodesc_t) * dp->dtdo_urelen);

                /*
                 * This code assumes the target of all relocations is the
                 * integer table 'intsec' (DOF_SECT_INTTAB).  If other sections
                 * need relocation in the future this will need to change.
                 */
                dofr.dofr_strtab = strsec;
                dofr.dofr_relsec = relsec;
                dofr.dofr_tgtsec = intsec;

                (void) dof_add_lsect(ddo, &dofr, DOF_SECT_URELHDR,
                    sizeof (dof_secidx_t), 0, 0, sizeof (dof_relohdr_t));
        }

        return (hdrsec);
}

static void
dof_add_translator(dt_dof_t *ddo, const dt_xlator_t *dxp, uint_t type)
{
        dtrace_hdl_t *dtp = ddo->ddo_hdl;
        dof_xlmember_t dofxm;
        dof_xlator_t dofxl;
        dof_secidx_t *xst;

        char buf[DT_TYPE_NAMELEN];
        dt_node_t *dnp;
        uint_t i = 0;

        assert(type == DOF_SECT_XLIMPORT || type == DOF_SECT_XLEXPORT);
        xst = type == DOF_SECT_XLIMPORT ? ddo->ddo_xlimport : ddo->ddo_xlexport;

        if (xst[dxp->dx_id] != DOF_SECIDX_NONE)
                return; /* translator has already been emitted */

        dt_buf_reset(dtp, &ddo->ddo_xlms);

        /*
         * Generate an array of dof_xlmember_t's into ddo_xlms.  If we are
         * importing the translator, add only those members referenced by the
         * program and set the dofxm_difo reference of each member to NONE.  If
         * we're exporting the translator, add all members and a DIFO for each.
         */
        for (dnp = dxp->dx_members; dnp != NULL; dnp = dnp->dn_list, i++) {
                if (type == DOF_SECT_XLIMPORT) {
                        if (!BT_TEST(ddo->ddo_pgp->dp_xrefs[dxp->dx_id], i))
                                continue; /* member is not referenced */
                        dofxm.dofxm_difo = DOF_SECIDX_NONE;
                } else {
                        dofxm.dofxm_difo = dof_add_difo(ddo,
                            dxp->dx_membdif[dnp->dn_membid]);
                }

                dofxm.dofxm_name = dof_add_string(ddo, dnp->dn_membname);
                dt_node_diftype(dtp, dnp, &dofxm.dofxm_type);

                dt_buf_write(dtp, &ddo->ddo_xlms,
                    &dofxm, sizeof (dofxm), sizeof (uint32_t));
        }

        dofxl.dofxl_members = dof_add_lsect(ddo, NULL, DOF_SECT_XLMEMBERS,
            sizeof (uint32_t), 0, sizeof (dofxm), dt_buf_len(&ddo->ddo_xlms));

        dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_xlms, sizeof (uint32_t));

        dofxl.dofxl_strtab = ddo->ddo_strsec;
        dofxl.dofxl_argv = dof_add_string(ddo, ctf_type_name(
            dxp->dx_src_ctfp, dxp->dx_src_type, buf, sizeof (buf)));
        dofxl.dofxl_argc = 1;
        dofxl.dofxl_type = dof_add_string(ddo, ctf_type_name(
            dxp->dx_dst_ctfp, dxp->dx_dst_type, buf, sizeof (buf)));
        dofxl.dofxl_attr = dof_attr(&dxp->dx_souid.di_attr);

        xst[dxp->dx_id] = dof_add_lsect(ddo, &dofxl, type,
            sizeof (uint32_t), 0, 0, sizeof (dofxl));
}

/*ARGSUSED*/
static int
dof_add_probe(dt_idhash_t *dhp, dt_ident_t *idp, void *data)
{
        dt_dof_t *ddo = data;
        dtrace_hdl_t *dtp = ddo->ddo_hdl;
        dt_probe_t *prp = idp->di_data;

        dof_probe_t dofpr;
        dof_relodesc_t dofr;
        dt_probe_instance_t *pip;
        dt_node_t *dnp;

        char buf[DT_TYPE_NAMELEN];
        uint_t i;

        dofpr.dofpr_addr = 0;
        dofpr.dofpr_name = dof_add_string(ddo, prp->pr_name);
        dofpr.dofpr_nargv = dt_buf_len(&ddo->ddo_strs);

        for (dnp = prp->pr_nargs; dnp != NULL; dnp = dnp->dn_list) {
                (void) dof_add_string(ddo, ctf_type_name(dnp->dn_ctfp,
                    dnp->dn_type, buf, sizeof (buf)));
        }

        dofpr.dofpr_xargv = dt_buf_len(&ddo->ddo_strs);

        for (dnp = prp->pr_xargs; dnp != NULL; dnp = dnp->dn_list) {
                (void) dof_add_string(ddo, ctf_type_name(dnp->dn_ctfp,
                    dnp->dn_type, buf, sizeof (buf)));
        }

        dofpr.dofpr_argidx = dt_buf_len(&ddo->ddo_args) / sizeof (uint8_t);

        for (i = 0; i < prp->pr_xargc; i++) {
                dt_buf_write(dtp, &ddo->ddo_args, &prp->pr_mapping[i],
                    sizeof (uint8_t), sizeof (uint8_t));
        }

        dofpr.dofpr_nargc = prp->pr_nargc;
        dofpr.dofpr_xargc = prp->pr_xargc;
        dofpr.dofpr_pad1 = 0;
        dofpr.dofpr_pad2 = 0;

        for (pip = prp->pr_inst; pip != NULL; pip = pip->pi_next) {
                dt_dprintf("adding probe for %s:%s\n", pip->pi_fname,
                    prp->pr_name);

                dofpr.dofpr_func = dof_add_string(ddo, pip->pi_fname);

                /*
                 * There should be one probe offset or is-enabled probe offset
                 * or else this probe instance won't have been created. The
                 * kernel will reject DOF which has a probe with no offsets.
                 */
                assert(pip->pi_noffs + pip->pi_nenoffs > 0);

                dofpr.dofpr_offidx =
                    dt_buf_len(&ddo->ddo_offs) / sizeof (uint32_t);
                dofpr.dofpr_noffs = pip->pi_noffs;
                dt_buf_write(dtp, &ddo->ddo_offs, pip->pi_offs,
                    pip->pi_noffs * sizeof (uint32_t), sizeof (uint32_t));

                dofpr.dofpr_enoffidx =
                    dt_buf_len(&ddo->ddo_enoffs) / sizeof (uint32_t);
                dofpr.dofpr_nenoffs = pip->pi_nenoffs;
                dt_buf_write(dtp, &ddo->ddo_enoffs, pip->pi_enoffs,
                    pip->pi_nenoffs * sizeof (uint32_t), sizeof (uint32_t));

                /*
                 * If pi_rname isn't set, the relocation will be against the
                 * function name. If it is, the relocation will be against
                 * pi_rname. This will be used if the function is scoped
                 * locally so an alternate symbol is added for the purpose
                 * of this relocation.
                 */
                if (pip->pi_rname[0] == '\0')
                        dofr.dofr_name = dofpr.dofpr_func;
                else
                        dofr.dofr_name = dof_add_string(ddo, pip->pi_rname);
                dofr.dofr_type = DOF_RELO_SETX;
                dofr.dofr_offset = dt_buf_len(&ddo->ddo_probes);
                dofr.dofr_data = 0;

                dt_buf_write(dtp, &ddo->ddo_rels, &dofr,
                    sizeof (dofr), sizeof (uint64_t));

                dt_buf_write(dtp, &ddo->ddo_probes, &dofpr,
                    sizeof (dofpr), sizeof (uint64_t));
        }

        return (0);
}

static int
dof_add_provider(dt_dof_t *ddo, const dt_provider_t *pvp)
{
        dtrace_hdl_t *dtp = ddo->ddo_hdl;
        dof_provider_t dofpv;
        dof_relohdr_t dofr;
        dof_secidx_t *dofs;
        ulong_t xr, nxr;
        size_t sz;
        id_t i;

        if (pvp->pv_flags & DT_PROVIDER_IMPL) {
                /*
                 * ignore providers that are exported by dtrace(7D)
                 */
                return (0);
        }

        nxr = dt_popcb(pvp->pv_xrefs, pvp->pv_xrmax);
        dofs = alloca(sizeof (dof_secidx_t) * (nxr + 1));
        xr = 1; /* reserve dofs[0] for the provider itself */

        /*
         * For each translator referenced by the provider (pv_xrefs), emit an
         * exported translator section for it if one hasn't been created yet.
         */
        for (i = 0; i < pvp->pv_xrmax; i++) {
                if (BT_TEST(pvp->pv_xrefs, i) &&
                    dtp->dt_xlatemode == DT_XL_DYNAMIC) {
                        dof_add_translator(ddo,
                            dt_xlator_lookup_id(dtp, i), DOF_SECT_XLEXPORT);
                        dofs[xr++] = ddo->ddo_xlexport[i];
                }
        }

        dt_buf_reset(dtp, &ddo->ddo_probes);
        dt_buf_reset(dtp, &ddo->ddo_args);
        dt_buf_reset(dtp, &ddo->ddo_offs);
        dt_buf_reset(dtp, &ddo->ddo_enoffs);
        dt_buf_reset(dtp, &ddo->ddo_rels);

        (void) dt_idhash_iter(pvp->pv_probes, dof_add_probe, ddo);

        if (dt_buf_len(&ddo->ddo_probes) == 0)
                return (dt_set_errno(dtp, EDT_NOPROBES));

        dofpv.dofpv_probes = dof_add_lsect(ddo, NULL, DOF_SECT_PROBES,
            sizeof (uint64_t), 0, sizeof (dof_probe_t),
            dt_buf_len(&ddo->ddo_probes));

        dt_buf_concat(dtp, &ddo->ddo_ldata,
            &ddo->ddo_probes, sizeof (uint64_t));

        dofpv.dofpv_prargs = dof_add_lsect(ddo, NULL, DOF_SECT_PRARGS,
            sizeof (uint8_t), 0, sizeof (uint8_t), dt_buf_len(&ddo->ddo_args));

        dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_args, sizeof (uint8_t));

        dofpv.dofpv_proffs = dof_add_lsect(ddo, NULL, DOF_SECT_PROFFS,
            sizeof (uint_t), 0, sizeof (uint_t), dt_buf_len(&ddo->ddo_offs));

        dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_offs, sizeof (uint_t));

        if ((sz = dt_buf_len(&ddo->ddo_enoffs)) != 0) {
                dofpv.dofpv_prenoffs = dof_add_lsect(ddo, NULL,
                    DOF_SECT_PRENOFFS, sizeof (uint_t), 0, sizeof (uint_t), sz);
        } else {
                dofpv.dofpv_prenoffs = DOF_SECT_NONE;
        }

        dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_enoffs, sizeof (uint_t));

        dofpv.dofpv_strtab = ddo->ddo_strsec;
        dofpv.dofpv_name = dof_add_string(ddo, pvp->pv_desc.dtvd_name);

        dofpv.dofpv_provattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_provider);
        dofpv.dofpv_modattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_mod);
        dofpv.dofpv_funcattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_func);
        dofpv.dofpv_nameattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_name);
        dofpv.dofpv_argsattr = dof_attr(&pvp->pv_desc.dtvd_attr.dtpa_args);

        dofs[0] = dof_add_lsect(ddo, &dofpv, DOF_SECT_PROVIDER,
            sizeof (dof_secidx_t), 0, 0, sizeof (dof_provider_t));

        dofr.dofr_strtab = dofpv.dofpv_strtab;
        dofr.dofr_tgtsec = dofpv.dofpv_probes;
        dofr.dofr_relsec = dof_add_lsect(ddo, NULL, DOF_SECT_RELTAB,
            sizeof (uint64_t), 0, sizeof (dof_relodesc_t),
            dt_buf_len(&ddo->ddo_rels));

        dt_buf_concat(dtp, &ddo->ddo_ldata, &ddo->ddo_rels, sizeof (uint64_t));

        (void) dof_add_lsect(ddo, &dofr, DOF_SECT_URELHDR,
            sizeof (dof_secidx_t), 0, 0, sizeof (dof_relohdr_t));

        if (nxr != 0 && dtp->dt_xlatemode == DT_XL_DYNAMIC) {
                (void) dof_add_lsect(ddo, dofs, DOF_SECT_PREXPORT,
                    sizeof (dof_secidx_t), 0, sizeof (dof_secidx_t),
                    sizeof (dof_secidx_t) * (nxr + 1));
        }

        return (0);
}

static int
dof_hdr(dtrace_hdl_t *dtp, uint8_t dofversion, dof_hdr_t *hp)
{
        /*
         * If our config values cannot fit in a uint8_t, we can't generate a
         * DOF header since the values won't fit.  This can only happen if the
         * user forcibly compiles a program with an artificial configuration.
         */
        if (dtp->dt_conf.dtc_difversion > UINT8_MAX ||
            dtp->dt_conf.dtc_difintregs > UINT8_MAX ||
            dtp->dt_conf.dtc_diftupregs > UINT8_MAX)
                return (dt_set_errno(dtp, EOVERFLOW));

        bzero(hp, sizeof (dof_hdr_t));

        hp->dofh_ident[DOF_ID_MAG0] = DOF_MAG_MAG0;
        hp->dofh_ident[DOF_ID_MAG1] = DOF_MAG_MAG1;
        hp->dofh_ident[DOF_ID_MAG2] = DOF_MAG_MAG2;
        hp->dofh_ident[DOF_ID_MAG3] = DOF_MAG_MAG3;

        if (dtp->dt_conf.dtc_ctfmodel == CTF_MODEL_LP64)
                hp->dofh_ident[DOF_ID_MODEL] = DOF_MODEL_LP64;
        else
                hp->dofh_ident[DOF_ID_MODEL] = DOF_MODEL_ILP32;

        hp->dofh_ident[DOF_ID_ENCODING] = DOF_ENCODE_NATIVE;
        hp->dofh_ident[DOF_ID_VERSION] = dofversion;
        hp->dofh_ident[DOF_ID_DIFVERS] = dtp->dt_conf.dtc_difversion;
        hp->dofh_ident[DOF_ID_DIFIREG] = dtp->dt_conf.dtc_difintregs;
        hp->dofh_ident[DOF_ID_DIFTREG] = dtp->dt_conf.dtc_diftupregs;

        hp->dofh_hdrsize = sizeof (dof_hdr_t);
        hp->dofh_secsize = sizeof (dof_sec_t);
        hp->dofh_secoff = sizeof (dof_hdr_t);

        return (0);
}

void *
dtrace_dof_create(dtrace_hdl_t *dtp, dtrace_prog_t *pgp, uint_t flags)
{
        dt_dof_t *ddo = &dtp->dt_dof;

        const dtrace_ecbdesc_t *edp, *last;
        const dtrace_probedesc_t *pdp;
        const dtrace_actdesc_t *ap;
        const dt_stmt_t *stp;

        uint_t maxacts = 0;
        uint_t maxfmt = 0;

        dt_provider_t *pvp;
        dt_xlator_t *dxp;
        dof_actdesc_t *dofa;
        dof_sec_t *sp;
        size_t ssize, lsize;
        dof_hdr_t h;

        dt_buf_t dof;
        char *fmt;
        uint_t i;

        if (flags & ~DTRACE_D_MASK) {
                (void) dt_set_errno(dtp, EINVAL);
                return (NULL);
        }

        flags |= dtp->dt_dflags;

        if (dof_hdr(dtp, pgp->dp_dofversion, &h) != 0)
                return (NULL);

        if (dt_dof_reset(dtp, pgp) != 0)
                return (NULL);

        /*
         * Iterate through the statement list computing the maximum number of
         * actions and the maximum format string for allocating local buffers.
         */
        for (last = NULL, stp = dt_list_next(&pgp->dp_stmts);
            stp != NULL; stp = dt_list_next(stp), last = edp) {

                dtrace_stmtdesc_t *sdp = stp->ds_desc;
                dtrace_actdesc_t *ap = sdp->dtsd_action;

                if (sdp->dtsd_fmtdata != NULL) {
                        i = dtrace_printf_format(dtp,
                            sdp->dtsd_fmtdata, NULL, 0);
                        maxfmt = MAX(maxfmt, i);
                }

                if ((edp = sdp->dtsd_ecbdesc) == last)
                        continue; /* same ecb as previous statement */

                for (i = 0, ap = edp->dted_action; ap; ap = ap->dtad_next)
                        i++;

                maxacts = MAX(maxacts, i);
        }

        dofa = alloca(sizeof (dof_actdesc_t) * maxacts);
        fmt = alloca(maxfmt + 1);

        ddo->ddo_strsec = dof_add_lsect(ddo, NULL, DOF_SECT_STRTAB, 1, 0, 0, 0);
        (void) dof_add_string(ddo, "");

        /*
         * If there are references to dynamic translators in the program, add
         * an imported translator table entry for each referenced translator.
         */
        if (pgp->dp_xrefslen != 0) {
                for (dxp = dt_list_next(&dtp->dt_xlators);
                    dxp != NULL; dxp = dt_list_next(dxp)) {
                        if (dxp->dx_id < pgp->dp_xrefslen &&
                            pgp->dp_xrefs[dxp->dx_id] != NULL)
                                dof_add_translator(ddo, dxp, DOF_SECT_XLIMPORT);
                }
        }

        /*
         * Now iterate through the statement list, creating the DOF section
         * headers and data for each one and adding them to our buffers.
         */
        for (last = NULL, stp = dt_list_next(&pgp->dp_stmts);
            stp != NULL; stp = dt_list_next(stp), last = edp) {

                dof_secidx_t probesec = DOF_SECIDX_NONE;
                dof_secidx_t prdsec = DOF_SECIDX_NONE;
                dof_secidx_t actsec = DOF_SECIDX_NONE;

                const dt_stmt_t *next = stp;
                dtrace_stmtdesc_t *sdp = stp->ds_desc;
                dof_stridx_t strndx = 0;
                dof_probedesc_t dofp;
                dof_ecbdesc_t dofe;
                uint_t i;

                if ((edp = stp->ds_desc->dtsd_ecbdesc) == last)
                        continue; /* same ecb as previous statement */

                pdp = &edp->dted_probe;

                /*
                 * Add a DOF_SECT_PROBEDESC for the ECB's probe description,
                 * and copy the probe description strings into the string table.
                 */
                dofp.dofp_strtab = ddo->ddo_strsec;
                dofp.dofp_provider = dof_add_string(ddo, pdp->dtpd_provider);
                dofp.dofp_mod = dof_add_string(ddo, pdp->dtpd_mod);
                dofp.dofp_func = dof_add_string(ddo, pdp->dtpd_func);
                dofp.dofp_name = dof_add_string(ddo, pdp->dtpd_name);
                dofp.dofp_id = pdp->dtpd_id;

                probesec = dof_add_lsect(ddo, &dofp, DOF_SECT_PROBEDESC,
                    sizeof (dof_secidx_t), 0,
                    sizeof (dof_probedesc_t), sizeof (dof_probedesc_t));

                /*
                 * If there is a predicate DIFO associated with the ecbdesc,
                 * write out the DIFO sections and save the DIFO section index.
                 */
                if (edp->dted_pred.dtpdd_difo != NULL)
                        prdsec = dof_add_difo(ddo, edp->dted_pred.dtpdd_difo);

                /*
                 * Now iterate through the action list generating DIFOs as
                 * referenced therein and adding action descriptions to 'dofa'.
                 */
                for (i = 0, ap = edp->dted_action;
                    ap != NULL; ap = ap->dtad_next, i++) {

                        if (ap->dtad_difo != NULL) {
                                dofa[i].dofa_difo =
                                    dof_add_difo(ddo, ap->dtad_difo);
                        } else
                                dofa[i].dofa_difo = DOF_SECIDX_NONE;

                        /*
                         * If the first action in a statement has string data,
                         * add the string to the global string table.  This can
                         * be due either to a printf() format string
                         * (dtsd_fmtdata) or a print() type string
                         * (dtsd_strdata).
                         */
                        if (sdp != NULL && ap == sdp->dtsd_action) {
                                if (sdp->dtsd_fmtdata != NULL) {
                                        (void) dtrace_printf_format(dtp,
                                            sdp->dtsd_fmtdata, fmt, maxfmt + 1);
                                        strndx = dof_add_string(ddo, fmt);
                                } else if (sdp->dtsd_strdata != NULL) {
                                        strndx = dof_add_string(ddo,
                                            sdp->dtsd_strdata);
                                } else {
                                        strndx = 0; /* use dtad_arg instead */
                                }

                                if ((next = dt_list_next(next)) != NULL)
                                        sdp = next->ds_desc;
                                else
                                        sdp = NULL;
                        }

                        if (strndx != 0) {
                                dofa[i].dofa_arg = strndx;
                                dofa[i].dofa_strtab = ddo->ddo_strsec;
                        } else {
                                dofa[i].dofa_arg = ap->dtad_arg;
                                dofa[i].dofa_strtab = DOF_SECIDX_NONE;
                        }

                        dofa[i].dofa_kind = ap->dtad_kind;
                        dofa[i].dofa_ntuple = ap->dtad_ntuple;
                        dofa[i].dofa_uarg = ap->dtad_uarg;
                }

                if (i > 0) {
                        actsec = dof_add_lsect(ddo, dofa, DOF_SECT_ACTDESC,
                            sizeof (uint64_t), 0, sizeof (dof_actdesc_t),
                            sizeof (dof_actdesc_t) * i);
                }

                /*
                 * Now finally, add the DOF_SECT_ECBDESC referencing all the
                 * previously created sub-sections.
                 */
                dofe.dofe_probes = probesec;
                dofe.dofe_pred = prdsec;
                dofe.dofe_actions = actsec;
                dofe.dofe_pad = 0;
                dofe.dofe_uarg = edp->dted_uarg;

                (void) dof_add_lsect(ddo, &dofe, DOF_SECT_ECBDESC,
                    sizeof (uint64_t), 0, 0, sizeof (dof_ecbdesc_t));
        }

        /*
         * If any providers are user-defined, output DOF sections corresponding
         * to the providers and the probes and arguments that they define.
         */
        if (flags & DTRACE_D_PROBES) {
                for (pvp = dt_list_next(&dtp->dt_provlist);
                    pvp != NULL; pvp = dt_list_next(pvp)) {
                        if (dof_add_provider(ddo, pvp) != 0)
                                return (NULL);
                }
        }

        /*
         * If we're not stripping unloadable sections, generate compiler
         * comments and any other unloadable miscellany.
         */
        if (!(flags & DTRACE_D_STRIP)) {
                (void) dof_add_usect(ddo, _dtrace_version, DOF_SECT_COMMENTS,
                    sizeof (char), 0, 0, strlen(_dtrace_version) + 1);
                (void) dof_add_usect(ddo, &dtp->dt_uts, DOF_SECT_UTSNAME,
                    sizeof (char), 0, 0, sizeof (struct utsname));
        }

        /*
         * Compute and fill in the appropriate values for the dof_hdr_t's
         * dofh_secnum, dofh_loadsz, and dofh_filez values.
         */
        h.dofh_secnum = ddo->ddo_nsecs;
        ssize = sizeof (h) + dt_buf_len(&ddo->ddo_secs);

        h.dofh_loadsz = ssize +
            dt_buf_len(&ddo->ddo_ldata) +
            dt_buf_len(&ddo->ddo_strs);

        if (dt_buf_len(&ddo->ddo_udata) != 0) {
                lsize = roundup(h.dofh_loadsz, sizeof (uint64_t));
                h.dofh_filesz = lsize + dt_buf_len(&ddo->ddo_udata);
        } else {
                lsize = h.dofh_loadsz;
                h.dofh_filesz = lsize;
        }

        /*
         * Set the global DOF_SECT_STRTAB's offset to be after the header,
         * section headers, and other loadable data.  Since we're going to
         * iterate over the buffer data directly, we must check for errors.
         */
        if ((i = dt_buf_error(&ddo->ddo_secs)) != 0) {
                (void) dt_set_errno(dtp, i);
                return (NULL);
        }

        sp = dt_buf_ptr(&ddo->ddo_secs);
        assert(sp[ddo->ddo_strsec].dofs_type == DOF_SECT_STRTAB);
        assert(ssize == sizeof (h) + sizeof (dof_sec_t) * ddo->ddo_nsecs);

        sp[ddo->ddo_strsec].dofs_offset = ssize + dt_buf_len(&ddo->ddo_ldata);
        sp[ddo->ddo_strsec].dofs_size = dt_buf_len(&ddo->ddo_strs);

        /*
         * Now relocate all the other section headers by adding the appropriate
         * delta to their respective dofs_offset values.
         */
        for (i = 0; i < ddo->ddo_nsecs; i++, sp++) {
                if (i == ddo->ddo_strsec)
                        continue; /* already relocated above */

                if (sp->dofs_flags & DOF_SECF_LOAD)
                        sp->dofs_offset += ssize;
                else
                        sp->dofs_offset += lsize;
        }

        /*
         * Finally, assemble the complete in-memory DOF buffer by writing the
         * header and then concatenating all our buffers.  dt_buf_concat() will
         * propagate any errors and cause dt_buf_claim() to return NULL.
         */
        dt_buf_create(dtp, &dof, "dof", h.dofh_filesz);

        dt_buf_write(dtp, &dof, &h, sizeof (h), sizeof (uint64_t));
        dt_buf_concat(dtp, &dof, &ddo->ddo_secs, sizeof (uint64_t));
        dt_buf_concat(dtp, &dof, &ddo->ddo_ldata, sizeof (uint64_t));
        dt_buf_concat(dtp, &dof, &ddo->ddo_strs, sizeof (char));
        dt_buf_concat(dtp, &dof, &ddo->ddo_udata, sizeof (uint64_t));

        return (dt_buf_claim(dtp, &dof));
}

void
dtrace_dof_destroy(dtrace_hdl_t *dtp, void *dof)
{
        dt_free(dtp, dof);
}

void *
dtrace_getopt_dof(dtrace_hdl_t *dtp)
{
        dof_hdr_t *dof;
        dof_sec_t *sec;
        dof_optdesc_t *dofo;
        int i, nopts = 0, len = sizeof (dof_hdr_t) +
            roundup(sizeof (dof_sec_t), sizeof (uint64_t));

        for (i = 0; i < DTRACEOPT_MAX; i++) {
                if (dtp->dt_options[i] != DTRACEOPT_UNSET)
                        nopts++;
        }

        len += sizeof (dof_optdesc_t) * nopts;

        if ((dof = dt_zalloc(dtp, len)) == NULL ||
            dof_hdr(dtp, DOF_VERSION, dof) != 0) {
                dt_free(dtp, dof);
                return (NULL);
        }

        dof->dofh_secnum = 1;   /* only DOF_SECT_OPTDESC */
        dof->dofh_loadsz = len;
        dof->dofh_filesz = len;

        /*
         * Fill in the option section header...
         */
        sec = (dof_sec_t *)((uintptr_t)dof + sizeof (dof_hdr_t));
        sec->dofs_type = DOF_SECT_OPTDESC;
        sec->dofs_align = sizeof (uint64_t);
        sec->dofs_flags = DOF_SECF_LOAD;
        sec->dofs_entsize = sizeof (dof_optdesc_t);

        dofo = (dof_optdesc_t *)((uintptr_t)sec +
            roundup(sizeof (dof_sec_t), sizeof (uint64_t)));

        sec->dofs_offset = (uintptr_t)dofo - (uintptr_t)dof;
        sec->dofs_size = sizeof (dof_optdesc_t) * nopts;

        for (i = 0; i < DTRACEOPT_MAX; i++) {
                if (dtp->dt_options[i] == DTRACEOPT_UNSET)
                        continue;

                dofo->dofo_option = i;
                dofo->dofo_strtab = DOF_SECIDX_NONE;
                dofo->dofo_value = dtp->dt_options[i];
                dofo++;
        }

        return (dof);
}

void *
dtrace_geterr_dof(dtrace_hdl_t *dtp)
{
        if (dtp->dt_errprog != NULL)
                return (dtrace_dof_create(dtp, dtp->dt_errprog, 0));

        (void) dt_set_errno(dtp, EDT_BADERROR);
        return (NULL);
}