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/* $NetBSD: uvm_glue.c,v 1.111 2007/08/18 10:07:55 ad 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 <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: uvm_glue.c,v 1.111 2007/08/18 10:07:55 ad Exp $");
#include "opt_coredump.h"
#include "opt_kgdb.h"
#include "opt_kstack.h"
#include "opt_uvmhist.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>
#include <sys/syncobj.h>
#include <sys/cpu.h>
#include <uvm/uvm.h>
/*
* local prototypes
*/
static void uvm_swapout(struct lwp *);
#define UVM_NUAREA_HIWAT 20
#define UVM_NUAREA_LOWAT 16
#define UAREA_NEXTFREE(uarea) (*(vaddr_t *)(UAREA_TO_USER(uarea)))
void uvm_uarea_free(vaddr_t);
/*
* XXXCDC: do these really belong here?
*/
/*
* uvm_kernacc: can the kernel access a region of memory
*
* - used only by /dev/kmem driver (mem.c)
*/
bool
uvm_kernacc(void *addr, size_t len, int rw)
{
bool rv;
vaddr_t saddr, eaddr;
vm_prot_t prot = rw == B_READ ? VM_PROT_READ : VM_PROT_WRITE;
saddr = trunc_page((vaddr_t)addr);
eaddr = round_page((vaddr_t)addr + len);
vm_map_lock_read(kernel_map);
rv = uvm_map_checkprot(kernel_map, saddr, eaddr, prot);
vm_map_unlock_read(kernel_map);
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(void *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((vaddr_t)addr + len);
for (sva = trunc_page((vaddr_t)addr); sva < eva; sva += PAGE_SIZE) {
/*
* Extract physical address for the page.
*/
if (pmap_extract(pmap_kernel(), sva, &pa) == false)
panic("chgkprot: invalid page");
pmap_enter(pmap_kernel(), sva, pa, prot, PMAP_WIRED);
}
pmap_update(pmap_kernel());
}
#endif
/*
* uvm_vslock: wire user memory for I/O
*
* - called from physio and sys___sysctl
* - XXXCDC: consider nuking this (or making it a macro?)
*/
int
uvm_vslock(struct vmspace *vs, void *addr, size_t len, vm_prot_t access_type)
{
struct vm_map *map;
vaddr_t start, end;
int error;
map = &vs->vm_map;
start = trunc_page((vaddr_t)addr);
end = round_page((vaddr_t)addr + len);
error = uvm_fault_wire(map, start, end, access_type, 0);
return error;
}
/*
* uvm_vsunlock: unwire user memory wired by uvm_vslock()
*
* - called from physio and sys___sysctl
* - XXXCDC: consider nuking this (or making it a macro?)
*/
void
uvm_vsunlock(struct vmspace *vs, void *addr, size_t len)
{
uvm_fault_unwire(&vs->vm_map, trunc_page((vaddr_t)addr),
round_page((vaddr_t)addr + len));
}
/*
* uvm_proc_fork: fork a virtual address space
*
* - the address space is copied as per parent map's inherit values
*/
void
uvm_proc_fork(struct proc *p1, struct proc *p2, bool shared)
{
if (shared == true) {
p2->p_vmspace = NULL;
uvmspace_share(p1, p2);
} else {
p2->p_vmspace = uvmspace_fork(p1->p_vmspace);
}
cpu_proc_fork(p1, p2);
}
/*
* uvm_lwp_fork: fork a thread
*
* - 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_lwp_fork returns in the child process. We do nothing here
* after cpu_lwp_fork returns.
* - XXXCDC: we need a way for this to return a failure value rather
* than just hang
*/
void
uvm_lwp_fork(struct lwp *l1, struct lwp *l2, void *stack, size_t stacksize,
void (*func)(void *), void *arg)
{
int error;
/*
* Wire down the U-area for the process, which contains the PCB
* and the kernel stack. Wired state is stored in l->l_flag's
* L_INMEM bit rather than in the vm_map_entry's wired count
* to prevent kernel_map fragmentation. If we reused a cached U-area,
* L_INMEM will already be set and we don't need to do anything.
*
* Note the kernel stack gets read/write accesses right off the bat.
*/
if ((l2->l_flag & LW_INMEM) == 0) {
vaddr_t uarea = USER_TO_UAREA(l2->l_addr);
error = uvm_fault_wire(kernel_map, uarea,
uarea + USPACE, VM_PROT_READ | VM_PROT_WRITE, 0);
if (error)
panic("uvm_lwp_fork: uvm_fault_wire failed: %d", error);
#ifdef PMAP_UAREA
/* Tell the pmap this is a u-area mapping */
PMAP_UAREA(uarea);
#endif
l2->l_flag |= LW_INMEM;
}
#ifdef KSTACK_CHECK_MAGIC
/*
* fill stack with magic number
*/
kstack_setup_magic(l2);
#endif
/*
* cpu_lwp_fork() copy and update the pcb, and make the child ready
* to run. If this is a normal user fork, the child will exit
* directly to user mode via child_return() on its first time
* slice and will not return here. If this is a kernel thread,
* the specified entry point will be executed.
*/
cpu_lwp_fork(l1, l2, stack, stacksize, func, arg);
}
/*
* uvm_cpu_attach: initialize per-CPU data structures.
*/
void
uvm_cpu_attach(struct cpu_info *ci)
{
mutex_init(&ci->ci_data.cpu_uarea_lock, MUTEX_DEFAULT, IPL_NONE);
ci->ci_data.cpu_uarea_cnt = 0;
ci->ci_data.cpu_uarea_list = 0;
}
/*
* uvm_uarea_alloc: allocate a u-area
*/
bool
uvm_uarea_alloc(vaddr_t *uaddrp)
{
struct cpu_info *ci;
vaddr_t uaddr;
#ifndef USPACE_ALIGN
#define USPACE_ALIGN 0
#endif
ci = curcpu();
if (ci->ci_data.cpu_uarea_cnt > 0) {
mutex_enter(&ci->ci_data.cpu_uarea_lock);
if (ci->ci_data.cpu_uarea_cnt == 0) {
mutex_exit(&ci->ci_data.cpu_uarea_lock);
} else {
uaddr = ci->ci_data.cpu_uarea_list;
ci->ci_data.cpu_uarea_list = UAREA_NEXTFREE(uaddr);
ci->ci_data.cpu_uarea_cnt--;
mutex_exit(&ci->ci_data.cpu_uarea_lock);
*uaddrp = uaddr;
return true;
}
}
*uaddrp = uvm_km_alloc(kernel_map, USPACE, USPACE_ALIGN,
UVM_KMF_PAGEABLE);
return false;
}
/*
* uvm_uarea_free: free a u-area
*/
void
uvm_uarea_free(vaddr_t uaddr)
{
struct cpu_info *ci;
ci = curcpu();
mutex_enter(&ci->ci_data.cpu_uarea_lock);
UAREA_NEXTFREE(uaddr) = ci->ci_data.cpu_uarea_list;
ci->ci_data.cpu_uarea_list = uaddr;
ci->ci_data.cpu_uarea_cnt++;
mutex_exit(&ci->ci_data.cpu_uarea_lock);
}
/*
* uvm_uarea_drain: return memory of u-areas over limit
* back to system
*
* => if asked to drain as much as possible, drain all cpus.
* => if asked to drain to low water mark, drain local cpu only.
*/
void
uvm_uarea_drain(bool empty)
{
CPU_INFO_ITERATOR cii;
struct cpu_info *ci;
vaddr_t uaddr, nuaddr;
int count;
if (empty) {
for (CPU_INFO_FOREACH(cii, ci)) {
mutex_enter(&ci->ci_data.cpu_uarea_lock);
count = ci->ci_data.cpu_uarea_cnt;
uaddr = ci->ci_data.cpu_uarea_list;
ci->ci_data.cpu_uarea_cnt = 0;
ci->ci_data.cpu_uarea_list = 0;
mutex_exit(&ci->ci_data.cpu_uarea_lock);
while (count != 0) {
nuaddr = UAREA_NEXTFREE(uaddr);
uvm_km_free(kernel_map, uaddr, USPACE,
UVM_KMF_PAGEABLE);
uaddr = nuaddr;
count--;
}
}
return;
}
ci = curcpu();
if (ci->ci_data.cpu_uarea_cnt > UVM_NUAREA_HIWAT) {
mutex_enter(&ci->ci_data.cpu_uarea_lock);
while (ci->ci_data.cpu_uarea_cnt > UVM_NUAREA_LOWAT) {
uaddr = ci->ci_data.cpu_uarea_list;
ci->ci_data.cpu_uarea_list = UAREA_NEXTFREE(uaddr);
ci->ci_data.cpu_uarea_cnt--;
mutex_exit(&ci->ci_data.cpu_uarea_lock);
uvm_km_free(kernel_map, uaddr, USPACE,
UVM_KMF_PAGEABLE);
mutex_enter(&ci->ci_data.cpu_uarea_lock);
}
mutex_exit(&ci->ci_data.cpu_uarea_lock);
}
}
/*
* 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).
* - borrow proc0's address space because freeing the vmspace
* of the dead process may block.
*/
void
uvm_proc_exit(struct proc *p)
{
struct lwp *l = curlwp; /* XXX */
struct vmspace *ovm;
KASSERT(p == l->l_proc);
ovm = p->p_vmspace;
/*
* borrow proc0's address space.
*/
pmap_deactivate(l);
p->p_vmspace = proc0.p_vmspace;
pmap_activate(l);
uvmspace_free(ovm);
}
void
uvm_lwp_exit(struct lwp *l)
{
vaddr_t va = USER_TO_UAREA(l->l_addr);
l->l_flag &= ~LW_INMEM;
uvm_uarea_free(va);
l->l_addr = NULL;
}
/*
* uvm_init_limit: init per-process VM limits
*
* - called for process 0 and then inherited by all others.
*/
void
uvm_init_limits(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 = maxsmap;
p->p_rlimit[RLIMIT_DATA].rlim_cur = DFLDSIZ;
p->p_rlimit[RLIMIT_DATA].rlim_max = maxdmap;
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 an lwp's u-area.
*
* - must be called with the LWP's swap lock held.
* - naturally, must not be called with l == curlwp
*/
void
uvm_swapin(struct lwp *l)
{
vaddr_t addr;
int error;
KASSERT(mutex_owned(&l->l_swaplock));
KASSERT(l != curlwp);
addr = USER_TO_UAREA(l->l_addr);
/* make L_INMEM true */
error = uvm_fault_wire(kernel_map, addr, addr + USPACE,
VM_PROT_READ | VM_PROT_WRITE, 0);
if (error) {
panic("uvm_swapin: rewiring stack failed: %d", error);
}
/*
* 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(l);
lwp_lock(l);
if (l->l_stat == LSRUN)
sched_enqueue(l, false);
l->l_flag |= LW_INMEM;
l->l_swtime = 0;
lwp_unlock(l);
++uvmexp.swapins;
}
/*
* uvm_kick_scheduler: kick the scheduler into action if not running.
*
* - called when swapped out processes have been awoken.
*/
void
uvm_kick_scheduler(void)
{
if (uvm.swap_running == false)
return;
mutex_enter(&uvm_scheduler_mutex);
uvm.scheduler_kicked = true;
cv_signal(&uvm.scheduler_cv);
mutex_exit(&uvm_scheduler_mutex);
}
/*
* 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(void)
{
struct lwp *l, *ll;
int pri;
int ppri;
l = curlwp;
lwp_lock(l);
l->l_priority = PVM;
l->l_usrpri = PVM;
lwp_unlock(l);
for (;;) {
#ifdef DEBUG
mutex_enter(&uvm_scheduler_mutex);
while (!enableswap)
cv_wait(&uvm.scheduler_cv, &uvm_scheduler_mutex);
mutex_exit(&uvm_scheduler_mutex);
#endif
ll = NULL; /* process to choose */
ppri = INT_MIN; /* its priority */
mutex_enter(&proclist_lock);
LIST_FOREACH(l, &alllwp, l_list) {
/* is it a runnable swapped out process? */
if (l->l_stat == LSRUN && !(l->l_flag & LW_INMEM)) {
pri = l->l_swtime + l->l_slptime -
(l->l_proc->p_nice - NZERO) * 8;
if (pri > ppri) { /* higher priority? */
ll = l;
ppri = pri;
}
}
}
#ifdef DEBUG
if (swapdebug & SDB_FOLLOW)
printf("scheduler: running, procp %p pri %d\n", ll,
ppri);
#endif
/*
* Nothing to do, back to sleep
*/
if ((l = ll) == NULL) {
mutex_exit(&proclist_lock);
mutex_enter(&uvm_scheduler_mutex);
if (uvm.scheduler_kicked == false)
cv_wait(&uvm.scheduler_cv,
&uvm_scheduler_mutex);
uvm.scheduler_kicked = false;
mutex_exit(&uvm_scheduler_mutex);
continue;
}
/*
* 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", l->l_proc->p_pid,
l->l_proc->p_comm, l->l_addr, ppri,
uvmexp.free);
#endif
mutex_enter(&l->l_swaplock);
mutex_exit(&proclist_lock);
uvm_swapin(l);
mutex_exit(&l->l_swaplock);
continue;
} else {
/*
* not enough memory, jab the pageout daemon and
* wait til the coast is clear
*/
mutex_exit(&proclist_lock);
#ifdef DEBUG
if (swapdebug & SDB_FOLLOW)
printf("scheduler: no room for pid %d(%s),"
" free %d\n", l->l_proc->p_pid,
l->l_proc->p_comm, uvmexp.free);
#endif
uvm_wait("schedpwait");
#ifdef DEBUG
if (swapdebug & SDB_FOLLOW)
printf("scheduler: room again, free %d\n",
uvmexp.free);
#endif
}
}
}
/*
* swappable: is LWP "l" swappable?
*/
static bool
swappable(struct lwp *l)
{
if ((l->l_flag & (LW_INMEM|LW_RUNNING|LW_SYSTEM|LW_WEXIT)) != LW_INMEM)
return false;
if (l->l_holdcnt != 0)
return false;
if (l->l_syncobj == &rw_syncobj || l->l_syncobj == &mutex_syncobj)
return false;
return true;
}
/*
* 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(void)
{
struct lwp *l;
struct lwp *outl, *outl2;
int outpri, outpri2;
int didswap = 0;
extern int maxslp;
bool gotit;
/* XXXCDC: should move off to uvmexp. or uvm., also in uvm_meter */
#ifdef DEBUG
if (!enableswap)
return;
#endif
/*
* outl/outpri : stop/sleep thread with largest sleeptime < maxslp
* outl2/outpri2: the longest resident thread (its swap time)
*/
outl = outl2 = NULL;
outpri = outpri2 = 0;
restart:
mutex_enter(&proclist_lock);
LIST_FOREACH(l, &alllwp, l_list) {
KASSERT(l->l_proc != NULL);
if (!mutex_tryenter(&l->l_swaplock))
continue;
if (!swappable(l)) {
mutex_exit(&l->l_swaplock);
continue;
}
switch (l->l_stat) {
case LSONPROC:
break;
case LSRUN:
if (l->l_swtime > outpri2) {
outl2 = l;
outpri2 = l->l_swtime;
}
break;
case LSSLEEP:
case LSSTOP:
if (l->l_slptime >= maxslp) {
mutex_exit(&proclist_lock);
uvm_swapout(l);
/*
* Locking in the wrong direction -
* try to prevent the LWP from exiting.
*/
gotit = mutex_tryenter(&proclist_lock);
mutex_exit(&l->l_swaplock);
didswap++;
if (!gotit)
goto restart;
continue;
} else if (l->l_slptime > outpri) {
outl = l;
outpri = l->l_slptime;
}
break;
}
mutex_exit(&l->l_swaplock);
}
/*
* 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 ((l = outl) == NULL)
l = outl2;
#ifdef DEBUG
if (swapdebug & SDB_SWAPOUT)
printf("swapout_threads: no duds, try procp %p\n", l);
#endif
if (l) {
mutex_enter(&l->l_swaplock);
mutex_exit(&proclist_lock);
if (swappable(l))
uvm_swapout(l);
mutex_exit(&l->l_swaplock);
return;
}
}
mutex_exit(&proclist_lock);
}
/*
* uvm_swapout: swap out lwp "l"
*
* - currently "swapout" means "unwire U-area" and "pmap_collect()"
* the pmap.
* - must be called with l->l_swaplock held.
* - XXXCDC: should deactivate all process' private anonymous memory
*/
static void
uvm_swapout(struct lwp *l)
{
vaddr_t addr;
struct proc *p = l->l_proc;
KASSERT(mutex_owned(&l->l_swaplock));
#ifdef DEBUG
if (swapdebug & SDB_SWAPOUT)
printf("swapout: lid %d.%d(%s)@%p, stat %x pri %d free %d\n",
p->p_pid, l->l_lid, p->p_comm, l->l_addr, l->l_stat,
l->l_slptime, uvmexp.free);
#endif
/*
* Mark it as (potentially) swapped out.
*/
lwp_lock(l);
if (!swappable(l)) {
KDASSERT(l->l_cpu != curcpu());
lwp_unlock(l);
return;
}
l->l_flag &= ~LW_INMEM;
l->l_swtime = 0;
if (l->l_stat == LSRUN)
sched_dequeue(l);
lwp_unlock(l);
p->p_stats->p_ru.ru_nswap++; /* XXXSMP */
++uvmexp.swapouts;
/*
* Do any machine-specific actions necessary before swapout.
* This can include saving floating point state, etc.
*/
cpu_swapout(l);
/*
* Unwire the to-be-swapped process's user struct and kernel stack.
*/
addr = USER_TO_UAREA(l->l_addr);
uvm_fault_unwire(kernel_map, addr, addr + USPACE); /* !L_INMEM */
pmap_collect(vm_map_pmap(&p->p_vmspace->vm_map));
}
/*
* uvm_lwp_hold: prevent lwp "l" from being swapped out, and bring
* back into memory if it is currently swapped.
*/
void
uvm_lwp_hold(struct lwp *l)
{
/* XXXSMP mutex_enter(&l->l_swaplock); */
if (l->l_holdcnt++ == 0 && (l->l_flag & LW_INMEM) == 0)
uvm_swapin(l);
/* XXXSMP mutex_exit(&l->l_swaplock); */
}
/*
* uvm_lwp_rele: release a hold on lwp "l". when the holdcount
* drops to zero, it's eligable to be swapped.
*/
void
uvm_lwp_rele(struct lwp *l)
{
KASSERT(l->l_holdcnt != 0);
/* XXXSMP mutex_enter(&l->l_swaplock); */
l->l_holdcnt--;
/* XXXSMP mutex_exit(&l->l_swaplock); */
}
#ifdef COREDUMP
/*
* uvm_coredump_walkmap: walk a process's map for the purpose of dumping
* a core file.
*/
int
uvm_coredump_walkmap(struct proc *p, void *iocookie,
int (*func)(struct proc *, void *, struct uvm_coredump_state *),
void *cookie)
{
struct uvm_coredump_state state;
struct vmspace *vm = p->p_vmspace;
struct vm_map *map = &vm->vm_map;
struct vm_map_entry *entry;
int error;
entry = NULL;
vm_map_lock_read(map);
state.end = 0;
for (;;) {
if (entry == NULL)
entry = map->header.next;
else if (!uvm_map_lookup_entry(map, state.end, &entry))
entry = entry->next;
if (entry == &map->header)
break;
state.cookie = cookie;
if (state.end > entry->start) {
state.start = state.end;
} else {
state.start = entry->start;
}
state.realend = entry->end;
state.end = entry->end;
state.prot = entry->protection;
state.flags = 0;
/*
* Dump the region unless one of the following is true:
*
* (1) the region has neither object nor amap behind it
* (ie. it has never been accessed).
*
* (2) the region has no amap and is read-only
* (eg. an executable text section).
*
* (3) the region's object is a device.
*
* (4) the region is unreadable by the process.
*/
KASSERT(!UVM_ET_ISSUBMAP(entry));
KASSERT(state.start < VM_MAXUSER_ADDRESS);
KASSERT(state.end <= VM_MAXUSER_ADDRESS);
if (entry->object.uvm_obj == NULL &&
entry->aref.ar_amap == NULL) {
state.realend = state.start;
} else if ((entry->protection & VM_PROT_WRITE) == 0 &&
entry->aref.ar_amap == NULL) {
state.realend = state.start;
} else if (entry->object.uvm_obj != NULL &&
UVM_OBJ_IS_DEVICE(entry->object.uvm_obj)) {
state.realend = state.start;
} else if ((entry->protection & VM_PROT_READ) == 0) {
state.realend = state.start;
} else {
if (state.start >= (vaddr_t)vm->vm_maxsaddr)
state.flags |= UVM_COREDUMP_STACK;
/*
* If this an anonymous entry, only dump instantiated
* pages.
*/
if (entry->object.uvm_obj == NULL) {
vaddr_t end;
amap_lock(entry->aref.ar_amap);
for (end = state.start;
end < state.end; end += PAGE_SIZE) {
struct vm_anon *anon;
anon = amap_lookup(&entry->aref,
end - entry->start);
/*
* If we have already encountered an
* uninstantiated page, stop at the
* first instantied page.
*/
if (anon != NULL &&
state.realend != state.end) {
state.end = end;
break;
}
/*
* If this page is the first
* uninstantiated page, mark this as
* the real ending point. Continue to
* counting uninstantiated pages.
*/
if (anon == NULL &&
state.realend == state.end) {
state.realend = end;
}
}
amap_unlock(entry->aref.ar_amap);
}
}
vm_map_unlock_read(map);
error = (*func)(p, iocookie, &state);
if (error)
return (error);
vm_map_lock_read(map);
}
vm_map_unlock_read(map);
return (0);
}
#endif /* COREDUMP */
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