/* $NetBSD: vm_machdep.c,v 1.108 2023/03/20 11:19:29 hannken Exp $ */ /* * Copyright (c) 1996 * The President and Fellows of Harvard College. All rights reserved. * Copyright (c) 1992, 1993 * The Regents of the University of California. All rights reserved. * * This software was developed by the Computer Systems Engineering group * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and * contributed to Berkeley. * * 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, Lawrence Berkeley Laboratory. * This product includes software developed by Harvard University. * * 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 Harvard University. * 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. * * @(#)vm_machdep.c 8.2 (Berkeley) 9/23/93 */ #include <sys/cdefs.h> __KERNEL_RCSID(0, "$NetBSD: vm_machdep.c,v 1.108 2023/03/20 11:19:29 hannken Exp $"); #include "opt_multiprocessor.h" #include <sys/param.h> #include <sys/systm.h> #include <sys/proc.h> #include <sys/core.h> #include <sys/kmem.h> #include <sys/buf.h> #include <sys/exec.h> #include <sys/vnode.h> #include <sys/cpu.h> #include <uvm/uvm_extern.h> #include <machine/cpu.h> #include <machine/frame.h> #include <machine/pcb.h> #include <machine/trap.h> #include <sparc/sparc/cpuvar.h> /* * Map a user I/O request into kernel virtual address space. * Note: the pages are already locked by uvm_vslock(), so we * do not need to pass an access_type to pmap_enter(). */ int vmapbuf(struct buf *bp, vsize_t len) { struct pmap *upmap, *kpmap; vaddr_t uva; /* User VA (map from) */ vaddr_t kva; /* Kernel VA (new to) */ paddr_t pa; /* physical address */ vsize_t off; if ((bp->b_flags & B_PHYS) == 0) panic("vmapbuf"); /* * XXX: It might be better to round/trunc to a * segment boundary to avoid VAC problems! */ bp->b_saveaddr = bp->b_data; uva = trunc_page((vaddr_t)bp->b_data); off = (vaddr_t)bp->b_data - uva; len = round_page(off + len); kva = uvm_km_alloc(kernel_map, len, 0, UVM_KMF_VAONLY | UVM_KMF_WAITVA); bp->b_data = (void *)(kva + off); /* * We have to flush any write-back cache on the * user-space mappings so our new mappings will * have the correct contents. */ if (CACHEINFO.c_vactype != VAC_NONE) cache_flush((void *)uva, len); upmap = vm_map_pmap(&bp->b_proc->p_vmspace->vm_map); kpmap = vm_map_pmap(kernel_map); do { if (pmap_extract(upmap, uva, &pa) == false) panic("vmapbuf: null page frame"); /* Now map the page into kernel space. */ pmap_enter(kpmap, kva, pa, VM_PROT_READ|VM_PROT_WRITE, PMAP_WIRED); uva += PAGE_SIZE; kva += PAGE_SIZE; len -= PAGE_SIZE; } while (len); pmap_update(kpmap); return 0; } /* * Unmap a previously-mapped user I/O request. */ void vunmapbuf(struct buf *bp, vsize_t len) { vaddr_t kva; vsize_t off; if ((bp->b_flags & B_PHYS) == 0) panic("vunmapbuf"); kva = trunc_page((vaddr_t)bp->b_data); off = (vaddr_t)bp->b_data - kva; len = round_page(off + len); pmap_remove(vm_map_pmap(kernel_map), kva, kva + len); pmap_update(vm_map_pmap(kernel_map)); uvm_km_free(kernel_map, kva, len, UVM_KMF_VAONLY); bp->b_data = bp->b_saveaddr; bp->b_saveaddr = NULL; #if 0 /* XXX: The flush above is sufficient, right? */ if (CACHEINFO.c_vactype != VAC_NONE) cpuinfo.cache_flush(bp->b_data, len); #endif } void cpu_proc_fork(struct proc *p1, struct proc *p2) { p2->p_md.md_flags = p1->p_md.md_flags; } /* * The offset of the topmost frame in the kernel stack. */ #define TOPFRAMEOFF (USPACE-sizeof(struct trapframe)-sizeof(struct frame)) /* * Finish a fork operation, with process l2 nearly set up. * Copy and update the pcb and trap frame, making the child ready to run. * * Rig the child's kernel stack so that it will start out in * lwp_trampoline() and call child_return() with l2 as an * argument. This causes the newly-created child process to go * directly to user level with an apparent return value of 0 from * fork(), while the parent process returns normally. * * l1 is the process being forked; if l1 == &lwp0, we are creating * a kernel thread, and the return path and argument are specified with * `func' and `arg'. * * If an alternate user-level stack is requested (with non-zero values * in both the stack and stacksize args), set up the user stack pointer * accordingly. */ void cpu_lwp_fork(struct lwp *l1, struct lwp *l2, void *stack, size_t stacksize, void (*func)(void *), void *arg) { struct pcb *opcb = lwp_getpcb(l1); struct pcb *npcb = lwp_getpcb(l2); struct trapframe *tf2; struct rwindow *rp; /* * Save all user registers to l1's stack or, in the case of * user registers and invalid stack pointers, to opcb. * We then copy the whole pcb to l2; when switch() selects l2 * to run, it will run at the `lwp_trampoline' stub, rather * than returning at the copying code below. * * If process l1 has an FPU state, we must copy it. If it is * the FPU user, we must save the FPU state first. */ if (l1 == curlwp) { write_user_windows(); opcb->pcb_psr = getpsr(); } #ifdef DIAGNOSTIC else if (l1 != &lwp0) /* XXX is this valid? */ panic("cpu_lwp_fork: curlwp"); #endif memcpy((void *)npcb, (void *)opcb, sizeof(struct pcb)); if (l1->l_md.md_fpstate != NULL) { struct cpu_info *cpi; int s; l2->l_md.md_fpstate = kmem_alloc(sizeof(struct fpstate), KM_SLEEP); FPU_LOCK(s); if ((cpi = l1->l_md.md_fpu) != NULL) { if (cpi->fplwp != l1) panic("FPU(%d): fplwp %p", cpi->ci_cpuid, cpi->fplwp); if (l1 == cpuinfo.fplwp) savefpstate(l1->l_md.md_fpstate); #if defined(MULTIPROCESSOR) else XCALL1(ipi_savefpstate, l1->l_md.md_fpstate, 1 << cpi->ci_cpuid); #endif } memcpy(l2->l_md.md_fpstate, l1->l_md.md_fpstate, sizeof(struct fpstate)); FPU_UNLOCK(s); } else l2->l_md.md_fpstate = NULL; l2->l_md.md_fpu = NULL; /* * Setup (kernel) stack frame that will by-pass the child * out of the kernel. (The trap frame invariably resides at * the tippity-top of the u. area.) */ tf2 = l2->l_md.md_tf = (struct trapframe *) ((int)npcb + USPACE - sizeof(*tf2)); /* Copy parent's trapframe */ *tf2 = *(struct trapframe *)((int)opcb + USPACE - sizeof(*tf2)); /* * If specified, give the child a different stack. */ if (stack != NULL) tf2->tf_out[6] = (u_int)stack + stacksize; /* * The fork system call always uses the old system call * convention; clear carry and skip trap instruction as * in syscall(). * note: lwp_trampoline() sets a fresh psr when returning * to user mode. */ /*tf2->tf_psr &= ~PSR_C; -* success */ /* Set return values in child mode */ tf2->tf_out[0] = 0; tf2->tf_out[1] = 1; /* Construct kernel frame to return to in cpu_switch() */ rp = (struct rwindow *)((u_int)npcb + TOPFRAMEOFF); /**rp = *(struct rwindow *)((u_int)opcb + TOPFRAMEOFF);*/ rp->rw_local[0] = (int)func; /* Function to call */ rp->rw_local[1] = (int)arg; /* and its argument */ rp->rw_local[2] = (int)l2; /* new LWP */ npcb->pcb_pc = (int)lwp_trampoline - 8; npcb->pcb_sp = (int)rp; npcb->pcb_psr &= ~PSR_CWP; /* Run in window #0 */ npcb->pcb_wim = 1; /* Fence at window #1 */ } /* * Cleanup FPU state. */ void cpu_lwp_free(struct lwp *l, int proc) { struct fpstate *fs; if ((fs = l->l_md.md_fpstate) != NULL) { struct cpu_info *cpi; int s; FPU_LOCK(s); if ((cpi = l->l_md.md_fpu) != NULL) { if (cpi->fplwp != l) panic("FPU(%d): fplwp %p", cpi->ci_cpuid, cpi->fplwp); if (l == cpuinfo.fplwp) savefpstate(fs); #if defined(MULTIPROCESSOR) else XCALL1(ipi_savefpstate, fs, 1 << cpi->ci_cpuid); #endif cpi->fplwp = NULL; } l->l_md.md_fpu = NULL; FPU_UNLOCK(s); } } void cpu_lwp_free2(struct lwp *l) { struct fpstate *fs; if ((fs = l->l_md.md_fpstate) != NULL) kmem_free(fs, sizeof(struct fpstate)); } int cpu_lwp_setprivate(lwp_t *l, void *addr) { struct trapframe *tf = l->l_md.md_tf; tf->tf_global[7] = (uintptr_t)addr; return 0; }
