/* * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * The Mach Operating System project at Carnegie-Mellon 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. 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_glue.c 8.6 (Berkeley) 1/5/94 * * * Copyright (c) 1987, 1990 Carnegie-Mellon University. * All rights reserved. * * 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. * * $FreeBSD: src/sys/vm/vm_glue.c,v 1.94.2.4 2003/01/13 22:51:17 dillon Exp $ */ #include <sys/param.h> #include <sys/systm.h> #include <sys/proc.h> #include <sys/resourcevar.h> #include <sys/buf.h> #include <sys/shm.h> #include <sys/vmmeter.h> #include <sys/sysctl.h> #include <sys/kernel.h> #include <sys/unistd.h> #include <machine/limits.h> #include <vm/vm.h> #include <vm/vm_param.h> #include <sys/lock.h> #include <vm/pmap.h> #include <vm/vm_map.h> #include <vm/vm_page.h> #include <vm/vm_page2.h> #include <vm/vm_pageout.h> #include <vm/vm_kern.h> #include <vm/vm_extern.h> /* * THIS MUST BE THE LAST INITIALIZATION ITEM!!! * * Process 0 falls into this function, just loop on nothing. */ static void scheduler(void *); SYSINIT(scheduler, SI_SUB_RUN_SCHEDULER, SI_ORDER_FIRST, scheduler, NULL); #ifdef INVARIANTS static int swap_debug = 0; SYSCTL_INT(_vm, OID_AUTO, swap_debug, CTLFLAG_RW, &swap_debug, 0, ""); #endif /* * No requirements. */ int kernacc(c_caddr_t addr, int len, int rw) { boolean_t rv; vm_offset_t saddr, eaddr; vm_prot_t prot; KASSERT((rw & (~VM_PROT_ALL)) == 0, ("illegal ``rw'' argument to kernacc (%x)", rw)); /* * The globaldata space is not part of the kernel_map proper, * check access separately. */ if (is_globaldata_space((vm_offset_t)addr, (vm_offset_t)(addr + len))) return (TRUE); /* * Nominal kernel memory access - check access via kernel_map. */ if ((vm_offset_t)addr + len > vm_map_max(kernel_map) || (vm_offset_t)addr + len < (vm_offset_t)addr) { return (FALSE); } prot = rw; saddr = trunc_page((vm_offset_t)addr); eaddr = round_page((vm_offset_t)addr + len); rv = vm_map_check_protection(kernel_map, saddr, eaddr, prot, FALSE); return (rv == TRUE); } /* * No requirements. */ int useracc(c_caddr_t addr, int len, int rw) { boolean_t rv; vm_prot_t prot; vm_map_t map; vm_offset_t wrap; KASSERT((rw & (~VM_PROT_ALL)) == 0, ("illegal ``rw'' argument to useracc (%x)", rw)); prot = rw; /* * XXX - check separately to disallow access to user area and user * page tables - they are in the map. */ wrap = (vm_offset_t)addr + len; if (wrap > VM_MAX_USER_ADDRESS || wrap < (vm_offset_t)addr) { return (FALSE); } map = &curproc->p_vmspace->vm_map; vm_map_lock_read(map); rv = vm_map_check_protection(map, trunc_page((vm_offset_t)addr), round_page(wrap), prot, TRUE); vm_map_unlock_read(map); return (rv == TRUE); } /* * No requirements. */ void vslock(caddr_t addr, u_int len) { if (len) { /* wire the pages */ vm_map_kernel_wiring(&curproc->p_vmspace->vm_map, trunc_page((vm_offset_t)addr), round_page((vm_offset_t)addr + len), 0); } } /* * No requirements. */ void vsunlock(caddr_t addr, u_int len) { if (len) { /* unwire the pages */ vm_map_kernel_wiring(&curproc->p_vmspace->vm_map, trunc_page((vm_offset_t)addr), round_page((vm_offset_t)addr + len), KM_PAGEABLE); } } /* * Implement fork's actions on an address space. Here we arrange for the * address space to be copied or referenced, allocate a user struct (pcb * and kernel stack), then call the machine-dependent layer to fill those * in and make the new process ready to run. The new process is set up * so that it returns directly to user mode to avoid stack copying and * relocation problems. * * If p2 is NULL and RFPROC is 0 we are just divorcing parts of the process * from itself. * * Otherwise if p2 is NULL the new vmspace is not to be associated with any * process or thread (so things like /dev/upmap and /dev/lpmap are not * retained). * * Otherwise if p2 is not NULL then process specific mappings will be forked. * If lp2 is not NULL only the thread-specific mappings for lp2 are forked, * otherwise no thread-specific mappings are forked. * * No requirements. */ void vm_fork(struct proc *p1, struct proc *p2, struct lwp *lp2, int flags) { if ((flags & RFPROC) == 0) { /* * Divorce the memory, if it is shared, essentially * this changes shared memory amongst threads, into * COW locally. */ if ((flags & RFMEM) == 0) { if (vmspace_getrefs(p1->p_vmspace) > 1) { vmspace_unshare(p1); } } cpu_fork(ONLY_LWP_IN_PROC(p1), NULL, flags); return; } if (flags & RFMEM) { vmspace_ref(p1->p_vmspace); p2->p_vmspace = p1->p_vmspace; } while (vm_paging_severe()) { vm_wait(0); } if ((flags & RFMEM) == 0) { p2->p_vmspace = vmspace_fork(p1->p_vmspace, p2, lp2); pmap_pinit2(vmspace_pmap(p2->p_vmspace)); if (p1->p_vmspace->vm_shm) shmfork(p1, p2); } pmap_init_proc(p2); } /* * Set default limits for VM system. Call during proc0's initialization. * * Called from the low level boot code only. */ void vm_init_limits(struct proc *p) { int rss_limit; /* * Set up the initial limits on process VM. Set the maximum resident * set size to be half of (reasonably) available memory. Since this * is a soft limit, it comes into effect only when the system is out * of memory - half of main memory helps to favor smaller processes, * and reduces thrashing of the object cache. */ p->p_rlimit[RLIMIT_STACK].rlim_cur = dflssiz; p->p_rlimit[RLIMIT_STACK].rlim_max = maxssiz; p->p_rlimit[RLIMIT_DATA].rlim_cur = dfldsiz; p->p_rlimit[RLIMIT_DATA].rlim_max = maxdsiz; /* limit the limit to no less than 2MB */ rss_limit = max(vmstats.v_free_count, 512); p->p_rlimit[RLIMIT_RSS].rlim_cur = ptoa(rss_limit); p->p_rlimit[RLIMIT_RSS].rlim_max = RLIM_INFINITY; } /* * process 0 winds up here after all kernel initialization sysinits have * run. */ static void scheduler(void *dummy) { for (;;) tsleep(&proc0, 0, "idle", 0); }
