/*- * 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. * * from: @(#)vm_machdep.c 7.3 (Berkeley) 5/13/91 * Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$ * $FreeBSD$ */ /* * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * quick version of vm_fault */ int vm_fault_quick(v, prot) caddr_t v; int prot; { int r; if (prot & VM_PROT_WRITE) r = subyte(v, fubyte(v)); else r = fubyte(v); return(r); } /* * 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 proc *p1; 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=%08x p2=%08x flags=%x", (u_int)td1, (u_int)p2, flags); if ((flags & RFPROC) == 0) return; p1 = td1->td_proc; pcb = (struct pcb *)((td2->td_kstack + KSTACK_PAGES * PAGE_SIZE - sizeof(struct pcb)) & ~0x2fU); 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)); /* XXX: Set up trap frame? */ td2->td_frame = tf; cf = (struct callframe *)tf - 1; 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; pcb->pcb_lr = (register_t)fork_trampoline; /* * 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_set_fork_handler(td, func, arg) struct thread *td; void (*func)(void *); void *arg; { struct callframe *cf; CTR3(KTR_PROC, "cpu_set_fork_handler: called with td=%08x func=%08x arg=%08x", (u_int)td, (u_int)func, (u_int)arg); cf = (struct callframe *)td->td_pcb->pcb_sp; cf->cf_func = (register_t)func; cf->cf_arg0 = (register_t)arg; } /* * cpu_exit is called as the last action during exit. * We release the address space of the process, block interrupts, * and call switch_exit. switch_exit switches to proc0's PCB and stack, * then jumps into the middle of cpu_switch, as if it were switching * from proc0. */ void cpu_exit(td) register struct thread *td; { } void cpu_wait(td) struct proc *td; { } /* Temporary helper */ void cpu_throw(void) { cpu_switch(); panic("cpu_throw() didn't"); } /* * Dump the machine specific header information at the start of a core dump. */ int cpu_coredump(td, vp, cred) struct thread *td; struct vnode *vp; struct ucred *cred; { return (vn_rdwr(UIO_WRITE, vp, (caddr_t)td->td_proc->p_uarea, ctob(UAREA_PAGES), (off_t)0, UIO_SYSSPACE, IO_UNIT, cred, (int *)NULL, td)); } /* * Map an IO request into kernel virtual address space. * * All requests are (re)mapped into kernel VA space. * Notice that we use b_bufsize for the size of the buffer * to be mapped. b_bcount might be modified by the driver. */ void vmapbuf(bp) register struct buf *bp; { register caddr_t addr, v, kva; vm_offset_t pa; GIANT_REQUIRED; if ((bp->b_flags & B_PHYS) == 0) panic("vmapbuf"); for (v = bp->b_saveaddr, addr = (caddr_t)trunc_page(bp->b_data); addr < bp->b_data + bp->b_bufsize; addr += PAGE_SIZE, v += PAGE_SIZE) { /* * Do the vm_fault if needed; do the copy-on-write thing * when reading stuff off device into memory. */ vm_fault_quick((addr >= bp->b_data) ? addr : bp->b_data, (bp->b_iocmd == BIO_READ)?(VM_PROT_READ|VM_PROT_WRITE):VM_PROT_READ); pa = trunc_page(pmap_kextract((vm_offset_t) addr)); if (pa == 0) panic("vmapbuf: page not present"); vm_page_hold(PHYS_TO_VM_PAGE(pa)); pmap_kenter((vm_offset_t) v, pa); } kva = bp->b_saveaddr; bp->b_saveaddr = bp->b_data; bp->b_data = kva + (((vm_offset_t) bp->b_data) & PAGE_MASK); } /* * Free the io map PTEs associated with this IO operation. * We also invalidate the TLB entries and restore the original b_addr. */ void vunmapbuf(bp) register struct buf *bp; { register caddr_t addr; vm_offset_t pa; GIANT_REQUIRED; if ((bp->b_flags & B_PHYS) == 0) panic("vunmapbuf"); for (addr = (caddr_t)trunc_page(bp->b_data); addr < bp->b_data + bp->b_bufsize; addr += PAGE_SIZE) { pa = trunc_page(pmap_kextract((vm_offset_t) addr)); pmap_kremove((vm_offset_t) addr); vm_page_unhold(PHYS_TO_VM_PAGE(pa)); } bp->b_data = bp->b_saveaddr; } /* * Reset back to firmware. */ void cpu_reset() { OF_exit(); } /* * Software interrupt handler for queued VM system processing. */ void swi_vm(void *dummy) { #if 0 /* XXX: Don't have busdma stuff yet */ if (busdma_swi_pending != 0) busdma_swi(); #endif } /* * Tell whether this address is in some physical memory region. * Currently used by the kernel coredump code in order to avoid * dumping the ``ISA memory hole'' which could cause indefinite hangs, * or other unpredictable behaviour. */ int is_physical_memory(addr) vm_offset_t addr; { /* * stuff other tests for known memory-mapped devices (PCI?) * here */ return 1; }