/*- * SPDX-License-Identifier: (BSD-4-Clause AND MIT-CMU) * * Copyright (c) 1982, 1986 The Regents of the University of California. * Copyright (c) 1989, 1990 William Jolitz * Copyright (c) 1994 John Dyson * All rights reserved. * * This code is derived from software contributed to Berkeley by * the Systems Programming Group of the University of Utah Computer * Science Department, and William Jolitz. * * 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. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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. * Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$ */ /*- * Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University. * All rights reserved. * * Author: Chris G. Demetriou * * Permission to use, copy, modify and distribute this software and * its documentation is hereby granted, provided that both the copyright * notice and this permission notice appear in all copies of the * software, derivative works or modified versions, and any portions * thereof, and that both notices appear in supporting documentation. * * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * Carnegie Mellon requests users of this software to return to * * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU * School of Computer Science * Carnegie Mellon University * Pittsburgh PA 15213-3890 * * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. */ #include <sys/param.h> #include <sys/systm.h> #include <sys/proc.h> #include <sys/malloc.h> #include <sys/bio.h> #include <sys/buf.h> #include <sys/ktr.h> #include <sys/lock.h> #include <sys/mutex.h> #include <sys/vnode.h> #include <sys/vmmeter.h> #include <sys/kernel.h> #include <sys/mbuf.h> #include <sys/sysctl.h> #include <sys/sysent.h> #include <sys/unistd.h> #include <machine/cpu.h> #include <machine/fpu.h> #include <machine/frame.h> #include <machine/md_var.h> #include <machine/pcb.h> #include <machine/reg.h> #include <dev/ofw/openfirm.h> #include <vm/vm.h> #include <vm/vm_param.h> #include <vm/vm_kern.h> #include <vm/vm_page.h> #include <vm/vm_map.h> #include <vm/vm_extern.h> /* * Finish a fork operation, with process p2 nearly set up. * Copy and update the pcb, set up the stack so that the child * ready to run and return to user mode. */ void cpu_fork(struct thread *td1, struct proc *p2, struct thread *td2, int flags) { struct trapframe *tf; struct callframe *cf; struct pcb *pcb; KASSERT(td1 == curthread || td1 == &thread0, ("cpu_fork: p1 not curproc and not proc0")); CTR3(KTR_PROC, "cpu_fork: called td1=%p p2=%p flags=%x", td1, p2, flags); if ((flags & RFPROC) == 0) return; /* Ensure td1 is up to date before copy. */ if (td1 == curthread) cpu_update_pcb(td1); pcb = (struct pcb *)__align_down(td2->td_kstack + td2->td_kstack_pages * PAGE_SIZE - sizeof(struct pcb), 0x40); td2->td_pcb = pcb; /* Copy the pcb */ bcopy(td1->td_pcb, pcb, sizeof(struct pcb)); /* * Create a fresh stack for the new process. * Copy the trap frame for the return to user mode as if from a * syscall. This copies most of the user mode register values. */ tf = (struct trapframe *)pcb - 1; bcopy(td1->td_frame, tf, sizeof(*tf)); /* Set up trap frame. */ tf->fixreg[FIRSTARG] = 0; tf->fixreg[FIRSTARG + 1] = 0; tf->cr &= ~0x10000000; td2->td_frame = tf; cf = (struct callframe *)tf - 1; memset(cf, 0, sizeof(struct callframe)); #if defined(__powerpc64__) && (!defined(_CALL_ELF) || _CALL_ELF == 1) cf->cf_toc = ((register_t *)fork_return)[1]; #endif cf->cf_func = (register_t)fork_return; cf->cf_arg0 = (register_t)td2; cf->cf_arg1 = (register_t)tf; pcb->pcb_sp = (register_t)cf; KASSERT(pcb->pcb_sp % 16 == 0, ("stack misaligned")); #if defined(__powerpc64__) && (!defined(_CALL_ELF) || _CALL_ELF == 1) pcb->pcb_lr = ((register_t *)fork_trampoline)[0]; pcb->pcb_toc = ((register_t *)fork_trampoline)[1]; #else pcb->pcb_lr = (register_t)fork_trampoline; pcb->pcb_context[0] = pcb->pcb_lr; #endif #ifdef AIM pcb->pcb_cpu.aim.usr_vsid = 0; #endif /* Setup to release spin count in fork_exit(). */ td2->td_md.md_spinlock_count = 1; td2->td_md.md_saved_msr = psl_kernset; /* * Now cpu_switch() can schedule the new process. */ } /* * Intercept the return address from a freshly forked process that has NOT * been scheduled yet. * * This is needed to make kernel threads stay in kernel mode. */ void cpu_fork_kthread_handler(struct thread *td, void (*func)(void *), void *arg) { struct callframe *cf; CTR4(KTR_PROC, "%s called with td=%p func=%p arg=%p", __func__, td, func, arg); cf = (struct callframe *)td->td_pcb->pcb_sp; #if defined(__powerpc64__) && (!defined(_CALL_ELF) || _CALL_ELF == 1) cf->cf_toc = ((register_t *)func)[1]; #endif cf->cf_func = (register_t)func; cf->cf_arg0 = (register_t)arg; } void cpu_exit(struct thread *td) { } /* * CPU threading functions related to the VM layer. These could be used * to map the SLB bits required for the kernel stack instead of forcing a * fixed-size KVA. */ bool cpu_exec_vmspace_reuse(struct proc *p __unused, vm_map_t map __unused) { return (true); } int cpu_procctl(struct thread *td __unused, int idtype __unused, id_t id __unused, int com __unused, void *data __unused) { return (EINVAL); } void cpu_sync_core(void) { /* * Linux performs "rfi" there. Our rendezvous IPI handler on * the target cpu does "rfi" before and lwsync/sync after the * action, which is stronger than required. */ }
