/*
 * 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 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright 2018 Joyent, Inc.
 * Copyright 2025 Oxide Computer Company
 */

/*
 * Libkvm Kernel Target Intel 32-bit component
 *
 * This file provides the ISA-dependent portion of the libkvm kernel target.
 * For more details on the implementation refer to mdb_kvm.c.
 */

#include <sys/types.h>
#include <sys/regset.h>
#include <sys/frame.h>
#include <sys/stack.h>
#include <sys/sysmacros.h>
#include <sys/panic.h>
#include <strings.h>

#include <mdb/mdb_target_impl.h>
#include <mdb/mdb_disasm.h>
#include <mdb/mdb_modapi.h>
#include <mdb/mdb_conf.h>
#include <mdb/mdb_stack.h>
#include <mdb/mdb_kreg_impl.h>
#include <mdb/mdb_isautil.h>
#include <mdb/mdb_ia32util.h>
#include <mdb/kvm_isadep.h>
#include <mdb/mdb_kvm.h>
#include <mdb/mdb_err.h>
#include <mdb/mdb_debug.h>
#include <mdb/mdb.h>


/*ARGSUSED*/
int
kt_regs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
        mdb_ia32_printregs((const mdb_tgt_gregset_t *)addr);
        return (DCMD_OK);
}

static int
kt_stack_common(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv,
    mdb_stack_frame_flags_t sflags, mdb_tgt_stack_f *func)
{
        mdb_tgt_t *t = mdb.m_target;
        kt_data_t *kt = t->t_data;
        mdb_tgt_gregset_t gregs, *grp;
        mdb_stack_frame_hdl_t *hdl;
        uint_t arglim = mdb.m_nargs;
        int i;

        if (flags & DCMD_ADDRSPEC) {
                bzero(&gregs, sizeof (gregs));
                gregs.kregs[KREG_EBP] = addr;
                grp = &gregs;
        } else
                grp = kt->k_regs;

        i = mdb_getopts(argc, argv,
            'n', MDB_OPT_SETBITS, MSF_ADDR, &sflags,
            's', MDB_OPT_SETBITS, MSF_SIZES, &sflags,
            't', MDB_OPT_SETBITS, MSF_TYPES, &sflags,
            'v', MDB_OPT_SETBITS, MSF_VERBOSE, &sflags,
            NULL);

        argc -= i;
        argv += i;

        if (argc != 0) {
                if (argv->a_type == MDB_TYPE_CHAR || argc > 1)
                        return (DCMD_USAGE);

                arglim = mdb_argtoull(argv);
        }

        if ((hdl = mdb_stack_frame_init(t, arglim, sflags)) == NULL) {
                mdb_warn("failed to init stack frame\n");
                return (DCMD_ERR);
        }

        (void) mdb_ia32_kvm_stack_iter(mdb.m_target, grp, func, (void *)hdl);
        return (DCMD_OK);
}

int
kt_stack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
        return (kt_stack_common(addr, flags, argc, argv, 0,
            mdb_ia32_kvm_frame));
}

int
kt_stackv(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
        return (kt_stack_common(addr, flags, argc, argv, MSF_VERBOSE,
            mdb_ia32_kvm_frame));
}

const mdb_tgt_ops_t kt_ia32_ops = {
        .t_setflags = kt_setflags,
        .t_setcontext = kt_setcontext,
        .t_activate = kt_activate,
        .t_deactivate = kt_deactivate,
        .t_periodic = (void (*)())(uintptr_t)mdb_tgt_nop,
        .t_destroy = kt_destroy,
        .t_name = kt_name,
        .t_isa = (const char *(*)())mdb_conf_isa,
        .t_platform = kt_platform,
        .t_uname = kt_uname,
        .t_dmodel = kt_dmodel,
        .t_aread = kt_aread,
        .t_awrite = kt_awrite,
        .t_vread = kt_vread,
        .t_vwrite = kt_vwrite,
        .t_pread = kt_pread,
        .t_pwrite = kt_pwrite,
        .t_fread = kt_fread,
        .t_fwrite = kt_fwrite,
        .t_ioread = (ssize_t (*)())mdb_tgt_notsup,
        .t_iowrite = (ssize_t (*)())mdb_tgt_notsup,
        .t_vtop = kt_vtop,
        .t_lookup_by_name = kt_lookup_by_name,
        .t_lookup_by_addr = kt_lookup_by_addr,
        .t_symbol_iter = kt_symbol_iter,
        .t_mapping_iter = kt_mapping_iter,
        .t_object_iter = kt_object_iter,
        .t_addr_to_map = kt_addr_to_map,
        .t_name_to_map = kt_name_to_map,
        .t_addr_to_ctf = kt_addr_to_ctf,
        .t_name_to_ctf = kt_name_to_ctf,
        .t_status = kt_status,
        .t_run = (int (*)())mdb_tgt_notsup,
        .t_step = (int (*)())mdb_tgt_notsup,
        .t_step_out = (int (*)())mdb_tgt_notsup,
        .t_next = (int (*)())mdb_tgt_notsup,
        .t_cont = (int (*)())mdb_tgt_notsup,
        .t_signal = (int (*)())mdb_tgt_notsup,
        .t_add_vbrkpt = (int (*)())(uintptr_t)mdb_tgt_null,
        .t_add_sbrkpt = (int (*)())(uintptr_t)mdb_tgt_null,
        .t_add_pwapt = (int (*)())(uintptr_t)mdb_tgt_null,
        .t_add_vwapt = (int (*)())(uintptr_t)mdb_tgt_null,
        .t_add_iowapt = (int (*)())(uintptr_t)mdb_tgt_null,
        .t_add_sysenter = (int (*)())(uintptr_t)mdb_tgt_null,
        .t_add_sysexit = (int (*)())(uintptr_t)mdb_tgt_null,
        .t_add_signal = (int (*)())(uintptr_t)mdb_tgt_null,
        .t_add_fault = (int (*)())(uintptr_t)mdb_tgt_null,
        .t_getareg = kt_getareg,
        .t_putareg = kt_putareg,
        .t_stack_iter = mdb_ia32_kvm_stack_iter,
        .t_auxv = (int (*)())mdb_tgt_notsup,
        .t_thread_name = (int (*)())(uintptr_t)mdb_tgt_notsup,
};

void
kt_regs_to_kregs(struct regs *regs, mdb_tgt_gregset_t *gregs)
{
        gregs->kregs[KREG_SAVFP] = regs->r_savfp;
        gregs->kregs[KREG_SAVPC] = regs->r_savpc;
        gregs->kregs[KREG_EAX] = regs->r_eax;
        gregs->kregs[KREG_EBX] = regs->r_ebx;
        gregs->kregs[KREG_ECX] = regs->r_ecx;
        gregs->kregs[KREG_EDX] = regs->r_edx;
        gregs->kregs[KREG_ESI] = regs->r_esi;
        gregs->kregs[KREG_EDI] = regs->r_edi;
        gregs->kregs[KREG_EBP] = regs->r_ebp;
        gregs->kregs[KREG_ESP] = regs->r_esp;
        gregs->kregs[KREG_CS] = regs->r_cs;
        gregs->kregs[KREG_DS] = regs->r_ds;
        gregs->kregs[KREG_SS] = regs->r_ss;
        gregs->kregs[KREG_ES] = regs->r_es;
        gregs->kregs[KREG_FS] = regs->r_fs;
        gregs->kregs[KREG_GS] = regs->r_gs;
        gregs->kregs[KREG_EFLAGS] = regs->r_efl;
        gregs->kregs[KREG_EIP] = regs->r_eip;
        gregs->kregs[KREG_UESP] = regs->r_uesp;
        gregs->kregs[KREG_TRAPNO] = regs->r_trapno;
        gregs->kregs[KREG_ERR] = regs->r_err;
}

void
kt_ia32_init(mdb_tgt_t *t)
{
        kt_data_t *kt = t->t_data;
        panic_data_t pd;
        label_t label;
        struct regs regs;
        kreg_t *kregs;
        uintptr_t addr;

        /*
         * Initialize the machine-dependent parts of the kernel target
         * structure.  Once this is complete and we fill in the ops
         * vector, the target is now fully constructed and we can use
         * the target API itself to perform the rest of our initialization.
         */
        kt->k_rds = mdb_ia32_kregs;
        kt->k_regs = mdb_zalloc(sizeof (mdb_tgt_gregset_t), UM_SLEEP);
        kt->k_regsize = sizeof (mdb_tgt_gregset_t);
        kt->k_dcmd_regs = kt_regs;
        kt->k_dcmd_stack = kt_stack;
        kt->k_dcmd_stackv = kt_stackv;
        kt->k_dcmd_stackr = kt_stackv;
        kt->k_dcmd_cpustack = kt_cpustack;
        kt->k_dcmd_cpuregs = kt_cpuregs;

        t->t_ops = &kt_ia32_ops;
        kregs = kt->k_regs->kregs;

        (void) mdb_dis_select("ia32");

        /*
         * Lookup the symbols corresponding to subroutines in locore.s where
         * we expect a saved regs structure to be pushed on the stack.  When
         * performing stack tracebacks we will attempt to detect interrupt
         * frames by comparing the %eip value to these symbols.
         */
        (void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
            "cmnint", &kt->k_intr_sym, NULL);

        (void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
            "cmntrap", &kt->k_trap_sym, NULL);

        /*
         * Don't attempt to load any thread or register information if
         * we're examining the live operating system.
         */
        if (kt->k_symfile != NULL && strcmp(kt->k_symfile, "/dev/ksyms") == 0)
                return;

        /*
         * If the panicbuf symbol is present and we can consume a panicbuf
         * header of the appropriate version from this address, then we can
         * initialize our current register set based on its contents.
         * Prior to the re-structuring of panicbuf, our only register data
         * was the panic_regs label_t, into which a setjmp() was performed,
         * or the panic_reg register pointer, which was only non-zero if
         * the system panicked as a result of a trap calling die().
         */
        if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &pd, sizeof (pd),
            MDB_TGT_OBJ_EXEC, "panicbuf") == sizeof (pd) &&
            pd.pd_version == PANICBUFVERS) {

                size_t pd_size = MIN(PANICBUFSIZE, pd.pd_msgoff);
                panic_data_t *pdp = mdb_zalloc(pd_size, UM_SLEEP);
                uint_t i, n;

                (void) mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, pdp, pd_size,
                    MDB_TGT_OBJ_EXEC, "panicbuf");

                n = (pd_size - (sizeof (panic_data_t) -
                    sizeof (panic_nv_t))) / sizeof (panic_nv_t);

                for (i = 0; i < n; i++) {
                        (void) kt_putareg(t, kt->k_tid,
                            pdp->pd_nvdata[i].pnv_name,
                            pdp->pd_nvdata[i].pnv_value);
                }

                mdb_free(pdp, pd_size);

                return;
        }

        if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &addr, sizeof (addr),
            MDB_TGT_OBJ_EXEC, "panic_reg") == sizeof (addr) && addr != 0 &&
            mdb_tgt_vread(t, &regs, sizeof (regs), addr) == sizeof (regs)) {
                kt_regs_to_kregs(&regs, kt->k_regs);
                return;
        }

        /*
         * If we can't read any panic regs, then our penultimate try is for any
         * CPU context that may have been stored (for example, in Xen core
         * dumps).  As this can only succeed for kernels with the above
         * methods available, we let it over-ride the older panic_regs method,
         * which will always manage to read the label_t, even if there's
         * nothing useful there.
         */
        if (kt_kvmregs(t, 0, kt->k_regs) == 0)
                return;

        if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &label, sizeof (label),
            MDB_TGT_OBJ_EXEC, "panic_regs") == sizeof (label)) {
                kregs[KREG_EDI] = label.val[0];
                kregs[KREG_ESI] = label.val[1];
                kregs[KREG_EBX] = label.val[2];
                kregs[KREG_EBP] = label.val[3];
                kregs[KREG_ESP] = label.val[4];
                kregs[KREG_EIP] = label.val[5];
                return;
        }

        warn("failed to read panicbuf, panic_reg and panic_regs -- "
            "current register set will be unavailable\n");
}