604 lines
16 KiB
C
604 lines
16 KiB
C
/* $NetBSD: uvm_glue.c,v 1.20 1999/05/13 21:58:38 thorpej Exp $ */
|
|
|
|
/*
|
|
* Copyright (c) 1997 Charles D. Cranor and Washington University.
|
|
* 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. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by Charles D. Cranor,
|
|
* Washington University, 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_glue.c 8.6 (Berkeley) 1/5/94
|
|
* from: Id: uvm_glue.c,v 1.1.2.8 1998/02/07 01:16:54 chs Exp
|
|
*
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include "opt_uvmhist.h"
|
|
#include "opt_sysv.h"
|
|
|
|
/*
|
|
* uvm_glue.c: glue functions
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/resourcevar.h>
|
|
#include <sys/buf.h>
|
|
#include <sys/user.h>
|
|
#ifdef SYSVSHM
|
|
#include <sys/shm.h>
|
|
#endif
|
|
|
|
#include <vm/vm.h>
|
|
#include <vm/vm_page.h>
|
|
#include <vm/vm_kern.h>
|
|
|
|
#include <uvm/uvm.h>
|
|
|
|
#include <machine/cpu.h>
|
|
|
|
/*
|
|
* local prototypes
|
|
*/
|
|
|
|
static void uvm_swapout __P((struct proc *));
|
|
|
|
/*
|
|
* XXXCDC: do these really belong here?
|
|
*/
|
|
|
|
unsigned maxdmap = MAXDSIZ; /* kern_resource.c: RLIMIT_DATA max */
|
|
unsigned maxsmap = MAXSSIZ; /* kern_resource.c: RLIMIT_STACK max */
|
|
|
|
int readbuffers = 0; /* allow KGDB to read kern buffer pool */
|
|
/* XXX: see uvm_kernacc */
|
|
|
|
|
|
/*
|
|
* uvm_kernacc: can the kernel access a region of memory
|
|
*
|
|
* - called from malloc [DIAGNOSTIC], and /dev/kmem driver (mem.c)
|
|
*/
|
|
|
|
boolean_t
|
|
uvm_kernacc(addr, len, rw)
|
|
caddr_t addr;
|
|
size_t len;
|
|
int rw;
|
|
{
|
|
boolean_t rv;
|
|
vaddr_t saddr, eaddr;
|
|
vm_prot_t prot = rw == B_READ ? VM_PROT_READ : VM_PROT_WRITE;
|
|
|
|
saddr = trunc_page(addr);
|
|
eaddr = round_page(addr+len);
|
|
vm_map_lock_read(kernel_map);
|
|
rv = uvm_map_checkprot(kernel_map, saddr, eaddr, prot);
|
|
vm_map_unlock_read(kernel_map);
|
|
|
|
/*
|
|
* XXX there are still some things (e.g. the buffer cache) that
|
|
* are managed behind the VM system's back so even though an
|
|
* address is accessible in the mind of the VM system, there may
|
|
* not be physical pages where the VM thinks there is. This can
|
|
* lead to bogus allocation of pages in the kernel address space
|
|
* or worse, inconsistencies at the pmap level. We only worry
|
|
* about the buffer cache for now.
|
|
*/
|
|
if (!readbuffers && rv && (eaddr > (vaddr_t)buffers &&
|
|
saddr < (vaddr_t)buffers + MAXBSIZE * nbuf))
|
|
rv = FALSE;
|
|
return(rv);
|
|
}
|
|
|
|
/*
|
|
* uvm_useracc: can the user access it?
|
|
*
|
|
* - called from physio() and sys___sysctl().
|
|
*/
|
|
|
|
boolean_t
|
|
uvm_useracc(addr, len, rw)
|
|
caddr_t addr;
|
|
size_t len;
|
|
int rw;
|
|
{
|
|
boolean_t rv;
|
|
vm_prot_t prot = rw == B_READ ? VM_PROT_READ : VM_PROT_WRITE;
|
|
|
|
#if defined(i386) || defined(pc532)
|
|
/*
|
|
* XXX - specially disallow access to user page tables - they are
|
|
* in the map. This is here until i386 & pc532 pmaps are fixed...
|
|
*/
|
|
if ((vaddr_t) addr >= VM_MAXUSER_ADDRESS
|
|
|| (vaddr_t) addr + len > VM_MAXUSER_ADDRESS
|
|
|| (vaddr_t) addr + len <= (vaddr_t) addr)
|
|
return (FALSE);
|
|
#endif
|
|
|
|
rv = uvm_map_checkprot(&curproc->p_vmspace->vm_map,
|
|
trunc_page(addr), round_page(addr+len), prot);
|
|
return(rv);
|
|
}
|
|
|
|
#ifdef KGDB
|
|
/*
|
|
* Change protections on kernel pages from addr to addr+len
|
|
* (presumably so debugger can plant a breakpoint).
|
|
*
|
|
* We force the protection change at the pmap level. If we were
|
|
* to use vm_map_protect a change to allow writing would be lazily-
|
|
* applied meaning we would still take a protection fault, something
|
|
* we really don't want to do. It would also fragment the kernel
|
|
* map unnecessarily. We cannot use pmap_protect since it also won't
|
|
* enforce a write-enable request. Using pmap_enter is the only way
|
|
* we can ensure the change takes place properly.
|
|
*/
|
|
void
|
|
uvm_chgkprot(addr, len, rw)
|
|
register caddr_t addr;
|
|
size_t len;
|
|
int rw;
|
|
{
|
|
vm_prot_t prot;
|
|
paddr_t pa;
|
|
vaddr_t sva, eva;
|
|
|
|
prot = rw == B_READ ? VM_PROT_READ : VM_PROT_READ|VM_PROT_WRITE;
|
|
eva = round_page(addr + len);
|
|
for (sva = trunc_page(addr); sva < eva; sva += PAGE_SIZE) {
|
|
/*
|
|
* Extract physical address for the page.
|
|
* We use a cheezy hack to differentiate physical
|
|
* page 0 from an invalid mapping, not that it
|
|
* really matters...
|
|
*/
|
|
pa = pmap_extract(pmap_kernel(), sva|1);
|
|
if (pa == 0)
|
|
panic("chgkprot: invalid page");
|
|
pmap_enter(pmap_kernel(), sva, pa&~1, prot, TRUE, 0);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* vslock: wire user memory for I/O
|
|
*
|
|
* - called from physio and sys___sysctl
|
|
* - XXXCDC: consider nuking this (or making it a macro?)
|
|
*/
|
|
|
|
void
|
|
uvm_vslock(p, addr, len)
|
|
struct proc *p;
|
|
caddr_t addr;
|
|
size_t len;
|
|
{
|
|
uvm_fault_wire(&p->p_vmspace->vm_map, trunc_page(addr),
|
|
round_page(addr+len));
|
|
}
|
|
|
|
/*
|
|
* vslock: wire user memory for I/O
|
|
*
|
|
* - called from physio and sys___sysctl
|
|
* - XXXCDC: consider nuking this (or making it a macro?)
|
|
*/
|
|
|
|
void
|
|
uvm_vsunlock(p, addr, len)
|
|
struct proc *p;
|
|
caddr_t addr;
|
|
size_t len;
|
|
{
|
|
uvm_fault_unwire(p->p_vmspace->vm_map.pmap, trunc_page(addr),
|
|
round_page(addr+len));
|
|
}
|
|
|
|
/*
|
|
* uvm_fork: fork a virtual address space
|
|
*
|
|
* - the address space is copied as per parent map's inherit values
|
|
* - a new "user" structure is allocated for the child process
|
|
* [filled in by MD layer...]
|
|
* - if specified, the child gets a new user stack described by
|
|
* stack and stacksize
|
|
* - NOTE: the kernel stack may be at a different location in the child
|
|
* process, and thus addresses of automatic variables may be invalid
|
|
* after cpu_fork returns in the child process. We do nothing here
|
|
* after cpu_fork returns.
|
|
* - XXXCDC: we need a way for this to return a failure value rather
|
|
* than just hang
|
|
*/
|
|
void
|
|
uvm_fork(p1, p2, shared, stack, stacksize)
|
|
struct proc *p1, *p2;
|
|
boolean_t shared;
|
|
void *stack;
|
|
size_t stacksize;
|
|
{
|
|
struct user *up = p2->p_addr;
|
|
int rv;
|
|
|
|
if (shared == TRUE)
|
|
uvmspace_share(p1, p2); /* share vmspace */
|
|
else
|
|
p2->p_vmspace = uvmspace_fork(p1->p_vmspace); /* fork vmspace */
|
|
|
|
/*
|
|
* Wire down the U-area for the process, which contains the PCB
|
|
* and the kernel stack. Wired state is stored in p->p_flag's
|
|
* P_INMEM bit rather than in the vm_map_entry's wired count
|
|
* to prevent kernel_map fragmentation.
|
|
*/
|
|
rv = uvm_fault_wire(kernel_map, (vaddr_t)up,
|
|
(vaddr_t)up + USPACE);
|
|
if (rv != KERN_SUCCESS)
|
|
panic("uvm_fork: uvm_fault_wire failed: %d", rv);
|
|
|
|
/*
|
|
* p_stats currently points at a field in the user struct. Copy
|
|
* parts of p_stats, and zero out the rest.
|
|
*/
|
|
p2->p_stats = &up->u_stats;
|
|
memset(&up->u_stats.pstat_startzero, 0,
|
|
(unsigned) ((caddr_t)&up->u_stats.pstat_endzero -
|
|
(caddr_t)&up->u_stats.pstat_startzero));
|
|
memcpy(&up->u_stats.pstat_startcopy, &p1->p_stats->pstat_startcopy,
|
|
((caddr_t)&up->u_stats.pstat_endcopy -
|
|
(caddr_t)&up->u_stats.pstat_startcopy));
|
|
|
|
/*
|
|
* cpu_fork will copy and update the kernel stack and pcb, and make
|
|
* the child ready to run. The child will exit directly to user
|
|
* mode on its first time slice, and will not return here.
|
|
*/
|
|
cpu_fork(p1, p2, stack, stacksize);
|
|
}
|
|
|
|
/*
|
|
* uvm_exit: exit a virtual address space
|
|
*
|
|
* - the process passed to us is a dead (pre-zombie) process; we
|
|
* are running on a different context now (the reaper).
|
|
* - we must run in a separate thread because freeing the vmspace
|
|
* of the dead process may block.
|
|
*/
|
|
void
|
|
uvm_exit(p)
|
|
struct proc *p;
|
|
{
|
|
|
|
uvmspace_free(p->p_vmspace);
|
|
uvm_km_free(kernel_map, (vaddr_t)p->p_addr, USPACE);
|
|
}
|
|
|
|
/*
|
|
* uvm_init_limit: init per-process VM limits
|
|
*
|
|
* - called for process 0 and then inherited by all others.
|
|
*/
|
|
void
|
|
uvm_init_limits(p)
|
|
struct proc *p;
|
|
{
|
|
|
|
/*
|
|
* Set up the initial limits on process VM. Set the maximum
|
|
* resident set size to be all of (reasonably) available memory.
|
|
* This causes any single, large process to start random page
|
|
* replacement once it fills memory.
|
|
*/
|
|
|
|
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;
|
|
p->p_rlimit[RLIMIT_RSS].rlim_cur = ptoa(uvmexp.free);
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
int enableswap = 1;
|
|
int swapdebug = 0;
|
|
#define SDB_FOLLOW 1
|
|
#define SDB_SWAPIN 2
|
|
#define SDB_SWAPOUT 4
|
|
#endif
|
|
|
|
/*
|
|
* uvm_swapin: swap in a process's u-area.
|
|
*/
|
|
|
|
void
|
|
uvm_swapin(p)
|
|
struct proc *p;
|
|
{
|
|
vaddr_t addr;
|
|
int s;
|
|
|
|
addr = (vaddr_t)p->p_addr;
|
|
/* make P_INMEM true */
|
|
uvm_fault_wire(kernel_map, addr, addr + USPACE);
|
|
|
|
/*
|
|
* Some architectures need to be notified when the user area has
|
|
* moved to new physical page(s) (e.g. see mips/mips/vm_machdep.c).
|
|
*/
|
|
cpu_swapin(p);
|
|
s = splstatclock();
|
|
if (p->p_stat == SRUN)
|
|
setrunqueue(p);
|
|
p->p_flag |= P_INMEM;
|
|
splx(s);
|
|
p->p_swtime = 0;
|
|
++uvmexp.swapins;
|
|
}
|
|
|
|
/*
|
|
* uvm_scheduler: process zero main loop
|
|
*
|
|
* - attempt to swapin every swaped-out, runnable process in order of
|
|
* priority.
|
|
* - if not enough memory, wake the pagedaemon and let it clear space.
|
|
*/
|
|
|
|
void
|
|
uvm_scheduler()
|
|
{
|
|
register struct proc *p;
|
|
register int pri;
|
|
struct proc *pp;
|
|
int ppri;
|
|
UVMHIST_FUNC("uvm_scheduler"); UVMHIST_CALLED(maphist);
|
|
|
|
loop:
|
|
#ifdef DEBUG
|
|
while (!enableswap)
|
|
tsleep((caddr_t)&proc0, PVM, "noswap", 0);
|
|
#endif
|
|
pp = NULL; /* process to choose */
|
|
ppri = INT_MIN; /* its priority */
|
|
for (p = allproc.lh_first; p != 0; p = p->p_list.le_next) {
|
|
|
|
/* is it a runnable swapped out process? */
|
|
if (p->p_stat == SRUN && (p->p_flag & P_INMEM) == 0) {
|
|
pri = p->p_swtime + p->p_slptime -
|
|
(p->p_nice - NZERO) * 8;
|
|
if (pri > ppri) { /* higher priority? remember it. */
|
|
pp = p;
|
|
ppri = pri;
|
|
}
|
|
}
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
if (swapdebug & SDB_FOLLOW)
|
|
printf("scheduler: running, procp %p pri %d\n", pp, ppri);
|
|
#endif
|
|
/*
|
|
* Nothing to do, back to sleep
|
|
*/
|
|
if ((p = pp) == NULL) {
|
|
tsleep((caddr_t)&proc0, PVM, "scheduler", 0);
|
|
goto loop;
|
|
}
|
|
|
|
/*
|
|
* we have found swapped out process which we would like to bring
|
|
* back in.
|
|
*
|
|
* XXX: this part is really bogus cuz we could deadlock on memory
|
|
* despite our feeble check
|
|
*/
|
|
if (uvmexp.free > atop(USPACE)) {
|
|
#ifdef DEBUG
|
|
if (swapdebug & SDB_SWAPIN)
|
|
printf("swapin: pid %d(%s)@%p, pri %d free %d\n",
|
|
p->p_pid, p->p_comm, p->p_addr, ppri, uvmexp.free);
|
|
#endif
|
|
uvm_swapin(p);
|
|
goto loop;
|
|
}
|
|
/*
|
|
* not enough memory, jab the pageout daemon and wait til the coast
|
|
* is clear
|
|
*/
|
|
#ifdef DEBUG
|
|
if (swapdebug & SDB_FOLLOW)
|
|
printf("scheduler: no room for pid %d(%s), free %d\n",
|
|
p->p_pid, p->p_comm, uvmexp.free);
|
|
#endif
|
|
(void) splhigh();
|
|
uvm_wait("schedpwait");
|
|
(void) spl0();
|
|
#ifdef DEBUG
|
|
if (swapdebug & SDB_FOLLOW)
|
|
printf("scheduler: room again, free %d\n", uvmexp.free);
|
|
#endif
|
|
goto loop;
|
|
}
|
|
|
|
/*
|
|
* swappable: is process "p" swappable?
|
|
*/
|
|
|
|
#define swappable(p) \
|
|
(((p)->p_flag & (P_SYSTEM | P_INMEM | P_WEXIT)) == P_INMEM && \
|
|
(p)->p_holdcnt == 0)
|
|
|
|
/*
|
|
* swapout_threads: find threads that can be swapped and unwire their
|
|
* u-areas.
|
|
*
|
|
* - called by the pagedaemon
|
|
* - try and swap at least one processs
|
|
* - processes that are sleeping or stopped for maxslp or more seconds
|
|
* are swapped... otherwise the longest-sleeping or stopped process
|
|
* is swapped, otherwise the longest resident process...
|
|
*/
|
|
void
|
|
uvm_swapout_threads()
|
|
{
|
|
register struct proc *p;
|
|
struct proc *outp, *outp2;
|
|
int outpri, outpri2;
|
|
int didswap = 0;
|
|
extern int maxslp;
|
|
/* XXXCDC: should move off to uvmexp. or uvm., also in uvm_meter */
|
|
|
|
#ifdef DEBUG
|
|
if (!enableswap)
|
|
return;
|
|
#endif
|
|
|
|
/*
|
|
* outp/outpri : stop/sleep process with largest sleeptime < maxslp
|
|
* outp2/outpri2: the longest resident process (its swap time)
|
|
*/
|
|
outp = outp2 = NULL;
|
|
outpri = outpri2 = 0;
|
|
for (p = allproc.lh_first; p != 0; p = p->p_list.le_next) {
|
|
if (!swappable(p))
|
|
continue;
|
|
switch (p->p_stat) {
|
|
case SRUN:
|
|
if (p->p_swtime > outpri2) {
|
|
outp2 = p;
|
|
outpri2 = p->p_swtime;
|
|
}
|
|
continue;
|
|
|
|
case SSLEEP:
|
|
case SSTOP:
|
|
if (p->p_slptime >= maxslp) {
|
|
uvm_swapout(p); /* zap! */
|
|
didswap++;
|
|
} else if (p->p_slptime > outpri) {
|
|
outp = p;
|
|
outpri = p->p_slptime;
|
|
}
|
|
continue;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If we didn't get rid of any real duds, toss out the next most
|
|
* likely sleeping/stopped or running candidate. We only do this
|
|
* if we are real low on memory since we don't gain much by doing
|
|
* it (USPACE bytes).
|
|
*/
|
|
if (didswap == 0 && uvmexp.free <= atop(round_page(USPACE))) {
|
|
if ((p = outp) == NULL)
|
|
p = outp2;
|
|
#ifdef DEBUG
|
|
if (swapdebug & SDB_SWAPOUT)
|
|
printf("swapout_threads: no duds, try procp %p\n", p);
|
|
#endif
|
|
if (p)
|
|
uvm_swapout(p);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* uvm_swapout: swap out process "p"
|
|
*
|
|
* - currently "swapout" means "unwire U-area" and "pmap_collect()"
|
|
* the pmap.
|
|
* - XXXCDC: should deactivate all process' private anonymous memory
|
|
*/
|
|
|
|
static void
|
|
uvm_swapout(p)
|
|
register struct proc *p;
|
|
{
|
|
vaddr_t addr;
|
|
int s;
|
|
|
|
#ifdef DEBUG
|
|
if (swapdebug & SDB_SWAPOUT)
|
|
printf("swapout: pid %d(%s)@%p, stat %x pri %d free %d\n",
|
|
p->p_pid, p->p_comm, p->p_addr, p->p_stat,
|
|
p->p_slptime, uvmexp.free);
|
|
#endif
|
|
|
|
/*
|
|
* Do any machine-specific actions necessary before swapout.
|
|
* This can include saving floating point state, etc.
|
|
*/
|
|
cpu_swapout(p);
|
|
|
|
/*
|
|
* Unwire the to-be-swapped process's user struct and kernel stack.
|
|
*/
|
|
addr = (vaddr_t)p->p_addr;
|
|
uvm_fault_unwire(kernel_map->pmap, addr, addr + USPACE); /* !P_INMEM */
|
|
pmap_collect(vm_map_pmap(&p->p_vmspace->vm_map));
|
|
|
|
/*
|
|
* Mark it as (potentially) swapped out.
|
|
*/
|
|
s = splstatclock();
|
|
p->p_flag &= ~P_INMEM;
|
|
if (p->p_stat == SRUN)
|
|
remrunqueue(p);
|
|
splx(s);
|
|
p->p_swtime = 0;
|
|
++uvmexp.swapouts;
|
|
}
|
|
|