root/sys/arm64/linux/linux_machdep.c
/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2018 Turing Robotic Industries Inc.
 * Copyright (c) 2000 Marcel Moolenaar
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/proc.h>
#include <sys/ptrace.h>
#include <sys/reg.h>

#include <vm/vm_param.h>

#include <arm64/linux/linux.h>
#include <arm64/linux/linux_proto.h>
#include <compat/linux/linux_fork.h>
#include <compat/linux/linux_misc.h>
#include <compat/linux/linux_util.h>

#define LINUX_ARCH_AARCH64              0xc00000b7


int
linux_set_upcall(struct thread *td, register_t stack)
{

        if (stack)
                td->td_frame->tf_sp = stack;

        /*
         * The newly created Linux thread returns
         * to the user space by the same path that a parent does.
         */
        td->td_frame->tf_x[0] = 0;
        return (0);
}

int
linux_set_cloned_tls(struct thread *td, void *desc)
{

        if ((uint64_t)desc >= VM_MAXUSER_ADDRESS)
                return (EPERM);

        return (cpu_set_user_tls(td, desc, 0));
}

void
bsd_to_linux_regset(const struct reg *b_reg, struct linux_pt_regset *l_regset)
{

        KASSERT(sizeof(l_regset->x) == sizeof(b_reg->x) + sizeof(l_ulong),
            ("%s: size mismatch\n", __func__));
        memcpy(l_regset->x, b_reg->x, sizeof(b_reg->x));

        l_regset->x[30] = b_reg->lr;
        l_regset->sp = b_reg->sp;
        l_regset->pc = b_reg->elr;
        l_regset->cpsr = b_reg->spsr;
}

void
linux_to_bsd_regset(struct reg *b_reg, const struct linux_pt_regset *l_regset)
{

        KASSERT(sizeof(l_regset->x) == sizeof(b_reg->x) + sizeof(l_ulong),
            ("%s: size mismatch\n", __func__));

        memcpy(b_reg->x, l_regset->x, sizeof(b_reg->x));
        b_reg->sp = l_regset->sp;
        b_reg->elr = l_regset->pc;
        b_reg->spsr = l_regset->cpsr;
}

void
linux_ptrace_get_syscall_info_machdep(const struct reg *reg,
    struct syscall_info *si)
{

        si->arch = LINUX_ARCH_AARCH64;
        si->instruction_pointer = reg->lr;
        si->stack_pointer = reg->sp;
}

int
linux_ptrace_getregs_machdep(struct thread *td __unused, pid_t pid __unused,
    struct linux_pt_regset *l_regset __unused)
{

        return (0);
}

int
linux_ptrace_peekuser(struct thread *td, pid_t pid, void *addr, void *data)
{

        LINUX_RATELIMIT_MSG_OPT1("PTRACE_PEEKUSER offset %ld not implemented; "
            "returning EINVAL", (uintptr_t)addr);
        return (EINVAL);
}

int
linux_ptrace_pokeuser(struct thread *td, pid_t pid, void *addr, void *data)
{

        LINUX_RATELIMIT_MSG_OPT1("PTRACE_POKEUSER offset %ld "
            "not implemented; returning EINVAL", (uintptr_t)addr);
        return (EINVAL);
}