/*- * Copyright (c) 2015 Ruslan Bukin * All rights reserved. * * Portions of this software were developed by SRI International and the * University of Cambridge Computer Laboratory under DARPA/AFRL contract * FA8750-10-C-0237 ("CTSRD"), as part of the DARPA CRASH research programme. * * Portions of this software were developed by the University of Cambridge * Computer Laboratory as part of the CTSRD Project, with support from the * UK Higher Education Innovation Fund (HEIF). * * 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 __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * 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 pcb *pcb2; struct trapframe *tf; if ((flags & RFPROC) == 0) return; pcb2 = (struct pcb *)(td2->td_kstack + td2->td_kstack_pages * PAGE_SIZE) - 1; td2->td_pcb = pcb2; bcopy(td1->td_pcb, pcb2, sizeof(*pcb2)); td2->td_pcb->pcb_l1addr = vtophys(vmspace_pmap(td2->td_proc->p_vmspace)->pm_l1); tf = (struct trapframe *)STACKALIGN((struct trapframe *)pcb2 - 1); bcopy(td1->td_frame, tf, sizeof(*tf)); /* Clear syscall error flag */ tf->tf_t[0] = 0; /* Arguments for child */ tf->tf_a[0] = 0; tf->tf_a[1] = 0; tf->tf_sstatus = SSTATUS_PIE; td2->td_frame = tf; /* Set the return value registers for fork() */ td2->td_pcb->pcb_s[0] = (uintptr_t)fork_return; td2->td_pcb->pcb_s[1] = (uintptr_t)td2; td2->td_pcb->pcb_ra = (uintptr_t)fork_trampoline; td2->td_pcb->pcb_sp = (uintptr_t)td2->td_frame; /* Setup to release spin count in fork_exit(). */ td2->td_md.md_spinlock_count = 1; td2->td_md.md_saved_sstatus_ie = 1; } void cpu_reset(void) { printf("cpu_reset"); while(1) __asm volatile("wfi" ::: "memory"); } void cpu_thread_swapin(struct thread *td) { } void cpu_thread_swapout(struct thread *td) { } void cpu_set_syscall_retval(struct thread *td, int error) { struct trapframe *frame; frame = td->td_frame; switch (error) { case 0: frame->tf_a[0] = td->td_retval[0]; frame->tf_a[1] = td->td_retval[1]; frame->tf_t[0] = 0; /* syscall succeeded */ break; case ERESTART: frame->tf_sepc -= 4; /* prev instruction */ break; case EJUSTRETURN: break; default: frame->tf_a[0] = error; frame->tf_t[0] = 1; /* syscall error */ break; } } /* * Initialize machine state, mostly pcb and trap frame for a new * thread, about to return to userspace. Put enough state in the new * thread's PCB to get it to go back to the fork_return(), which * finalizes the thread state and handles peculiarities of the first * return to userspace for the new thread. */ void cpu_copy_thread(struct thread *td, struct thread *td0) { bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe)); bcopy(td0->td_pcb, td->td_pcb, sizeof(struct pcb)); td->td_pcb->pcb_s[0] = (uintptr_t)fork_return; td->td_pcb->pcb_s[1] = (uintptr_t)td; td->td_pcb->pcb_ra = (uintptr_t)fork_trampoline; td->td_pcb->pcb_sp = (uintptr_t)td->td_frame; /* Setup to release spin count in fork_exit(). */ td->td_md.md_spinlock_count = 1; td->td_md.md_saved_sstatus_ie = 1; } /* * Set that machine state for performing an upcall that starts * the entry function with the given argument. */ void cpu_set_upcall(struct thread *td, void (*entry)(void *), void *arg, stack_t *stack) { struct trapframe *tf = td->td_frame; tf->tf_sp = STACKALIGN((uintptr_t)stack->ss_sp + stack->ss_size); tf->tf_sepc = (register_t)entry; tf->tf_a[0] = (register_t)arg; } int cpu_set_user_tls(struct thread *td, void *tls_base) { struct pcb *pcb; if ((uintptr_t)tls_base >= VM_MAXUSER_ADDRESS) return (EINVAL); pcb = td->td_pcb; pcb->pcb_tp = (register_t)tls_base; return (0); } void cpu_thread_exit(struct thread *td) { } void cpu_thread_alloc(struct thread *td) { td->td_pcb = (struct pcb *)(td->td_kstack + td->td_kstack_pages * PAGE_SIZE) - 1; td->td_frame = (struct trapframe *)STACKALIGN( (caddr_t)td->td_pcb - 8 - sizeof(struct trapframe)); } void cpu_thread_free(struct thread *td) { } void cpu_thread_clean(struct thread *td) { } /* * 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) { td->td_pcb->pcb_s[0] = (uintptr_t)func; td->td_pcb->pcb_s[1] = (uintptr_t)arg; td->td_pcb->pcb_ra = (uintptr_t)fork_trampoline; td->td_pcb->pcb_sp = (uintptr_t)td->td_frame; } void cpu_exit(struct thread *td) { } void swi_vm(void *v) { /* Nothing to do here - busdma bounce buffers are not implemented. */ }