bf0acc273a
switch to. If a non-NULL thread pointer is passed in, then the CPU will switch to that thread directly rather than calling choosethread() to pick a thread to choose to. - Make sched_switch() aware of idle threads and know to do TD_SET_CAN_RUN() instead of sticking them on the run queue rather than requiring all callers of mi_switch() to know to do this if they can be called from an idlethread. - Move constants for arguments to mi_switch() and thread_single() out of the middle of the function prototypes and up above into their own section.
514 lines
12 KiB
C
514 lines
12 KiB
C
/*
|
|
* Copyright (c) 1982, 1986, 1991, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
* (c) UNIX System Laboratories, Inc.
|
|
* All or some portions of this file are derived from material licensed
|
|
* to the University of California by American Telephone and Telegraph
|
|
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
|
|
* the permission of UNIX System Laboratories, Inc.
|
|
*
|
|
* 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.
|
|
* 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.
|
|
*
|
|
* @(#)kern_subr.c 8.3 (Berkeley) 1/21/94
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include "opt_zero.h"
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/ktr.h>
|
|
#include <sys/limits.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/resourcevar.h>
|
|
#include <sys/sched.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/vnode.h>
|
|
|
|
#include <vm/vm.h>
|
|
#include <vm/vm_page.h>
|
|
#include <vm/vm_map.h>
|
|
#ifdef ZERO_COPY_SOCKETS
|
|
#include <vm/vm_param.h>
|
|
#include <vm/vm_object.h>
|
|
#endif
|
|
|
|
SYSCTL_INT(_kern, KERN_IOV_MAX, iov_max, CTLFLAG_RD, NULL, UIO_MAXIOV,
|
|
"Maximum number of elements in an I/O vector; sysconf(_SC_IOV_MAX)");
|
|
|
|
#ifdef ZERO_COPY_SOCKETS
|
|
/* Declared in uipc_socket.c */
|
|
extern int so_zero_copy_receive;
|
|
|
|
static int
|
|
vm_pgmoveco(vm_map_t mapa, vm_object_t srcobj, vm_offset_t kaddr,
|
|
vm_offset_t uaddr)
|
|
{
|
|
vm_map_t map = mapa;
|
|
vm_page_t kern_pg, user_pg;
|
|
vm_object_t uobject;
|
|
vm_map_entry_t entry;
|
|
vm_pindex_t upindex, kpindex;
|
|
vm_prot_t prot;
|
|
boolean_t wired;
|
|
|
|
/*
|
|
* First lookup the kernel page.
|
|
*/
|
|
kern_pg = PHYS_TO_VM_PAGE(vtophys(kaddr));
|
|
/*
|
|
* XXX The vm object containing kern_pg needs locking.
|
|
*/
|
|
if ((vm_map_lookup(&map, uaddr,
|
|
VM_PROT_WRITE, &entry, &uobject,
|
|
&upindex, &prot, &wired)) != KERN_SUCCESS) {
|
|
return(EFAULT);
|
|
}
|
|
VM_OBJECT_LOCK(uobject);
|
|
if ((user_pg = vm_page_lookup(uobject, upindex)) != NULL) {
|
|
do
|
|
vm_page_lock_queues();
|
|
while (vm_page_sleep_if_busy(user_pg, 1, "vm_pgmoveco"));
|
|
vm_page_busy(user_pg);
|
|
pmap_remove_all(user_pg);
|
|
vm_page_free(user_pg);
|
|
} else
|
|
vm_page_lock_queues();
|
|
if (kern_pg->busy || ((kern_pg->queue - kern_pg->pc) == PQ_FREE) ||
|
|
(kern_pg->hold_count != 0)|| (kern_pg->flags & PG_BUSY)) {
|
|
printf("vm_pgmoveco: pindex(%lu), busy(%d), PG_BUSY(%d), "
|
|
"hold(%d) paddr(0x%lx)\n", (u_long)kern_pg->pindex,
|
|
kern_pg->busy, (kern_pg->flags & PG_BUSY) ? 1 : 0,
|
|
kern_pg->hold_count, (u_long)kern_pg->phys_addr);
|
|
if ((kern_pg->queue - kern_pg->pc) == PQ_FREE)
|
|
panic("vm_pgmoveco: renaming free page");
|
|
else
|
|
panic("vm_pgmoveco: renaming busy page");
|
|
}
|
|
kpindex = kern_pg->pindex;
|
|
vm_page_busy(kern_pg);
|
|
vm_page_rename(kern_pg, uobject, upindex);
|
|
vm_page_flag_clear(kern_pg, PG_BUSY);
|
|
kern_pg->valid = VM_PAGE_BITS_ALL;
|
|
vm_page_unlock_queues();
|
|
VM_OBJECT_UNLOCK(uobject);
|
|
vm_map_lookup_done(map, entry);
|
|
return(KERN_SUCCESS);
|
|
}
|
|
#endif /* ZERO_COPY_SOCKETS */
|
|
|
|
int
|
|
uiomove(void *cp, int n, struct uio *uio)
|
|
{
|
|
struct thread *td = curthread;
|
|
struct iovec *iov;
|
|
u_int cnt;
|
|
int error = 0;
|
|
int save = 0;
|
|
|
|
KASSERT(uio->uio_rw == UIO_READ || uio->uio_rw == UIO_WRITE,
|
|
("uiomove: mode"));
|
|
KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread,
|
|
("uiomove proc"));
|
|
|
|
save = td->td_pflags & TDP_DEADLKTREAT;
|
|
td->td_pflags |= TDP_DEADLKTREAT;
|
|
|
|
while (n > 0 && uio->uio_resid) {
|
|
iov = uio->uio_iov;
|
|
cnt = iov->iov_len;
|
|
if (cnt == 0) {
|
|
uio->uio_iov++;
|
|
uio->uio_iovcnt--;
|
|
continue;
|
|
}
|
|
if (cnt > n)
|
|
cnt = n;
|
|
|
|
switch (uio->uio_segflg) {
|
|
|
|
case UIO_USERSPACE:
|
|
if (ticks - PCPU_GET(switchticks) >= hogticks)
|
|
uio_yield();
|
|
if (uio->uio_rw == UIO_READ)
|
|
error = copyout(cp, iov->iov_base, cnt);
|
|
else
|
|
error = copyin(iov->iov_base, cp, cnt);
|
|
if (error)
|
|
goto out;
|
|
break;
|
|
|
|
case UIO_SYSSPACE:
|
|
if (uio->uio_rw == UIO_READ)
|
|
bcopy(cp, iov->iov_base, cnt);
|
|
else
|
|
bcopy(iov->iov_base, cp, cnt);
|
|
break;
|
|
case UIO_NOCOPY:
|
|
break;
|
|
}
|
|
iov->iov_base = (char *)iov->iov_base + cnt;
|
|
iov->iov_len -= cnt;
|
|
uio->uio_resid -= cnt;
|
|
uio->uio_offset += cnt;
|
|
cp = (char *)cp + cnt;
|
|
n -= cnt;
|
|
}
|
|
out:
|
|
if (save == 0)
|
|
td->td_pflags &= ~TDP_DEADLKTREAT;
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Wrapper for uiomove() that validates the arguments against a known-good
|
|
* kernel buffer. Currently, uiomove accepts a signed (n) argument, which
|
|
* is almost definitely a bad thing, so we catch that here as well. We
|
|
* return a runtime failure, but it might be desirable to generate a runtime
|
|
* assertion failure instead.
|
|
*/
|
|
int
|
|
uiomove_frombuf(void *buf, int buflen, struct uio *uio)
|
|
{
|
|
unsigned int offset, n;
|
|
|
|
if (uio->uio_offset < 0 || uio->uio_resid < 0 ||
|
|
(offset = uio->uio_offset) != uio->uio_offset)
|
|
return (EINVAL);
|
|
if (buflen <= 0 || offset >= buflen)
|
|
return (0);
|
|
if ((n = buflen - offset) > INT_MAX)
|
|
return (EINVAL);
|
|
return (uiomove((char *)buf + offset, n, uio));
|
|
}
|
|
|
|
#ifdef ZERO_COPY_SOCKETS
|
|
/*
|
|
* Experimental support for zero-copy I/O
|
|
*/
|
|
static int
|
|
userspaceco(void *cp, u_int cnt, struct uio *uio, struct vm_object *obj,
|
|
int disposable)
|
|
{
|
|
struct iovec *iov;
|
|
int error;
|
|
|
|
iov = uio->uio_iov;
|
|
if (uio->uio_rw == UIO_READ) {
|
|
if ((so_zero_copy_receive != 0)
|
|
&& (obj != NULL)
|
|
&& ((cnt & PAGE_MASK) == 0)
|
|
&& ((((intptr_t) iov->iov_base) & PAGE_MASK) == 0)
|
|
&& ((uio->uio_offset & PAGE_MASK) == 0)
|
|
&& ((((intptr_t) cp) & PAGE_MASK) == 0)
|
|
&& (obj->type == OBJT_DEFAULT)
|
|
&& (disposable != 0)) {
|
|
/* SOCKET: use page-trading */
|
|
/*
|
|
* We only want to call vm_pgmoveco() on
|
|
* disposeable pages, since it gives the
|
|
* kernel page to the userland process.
|
|
*/
|
|
error = vm_pgmoveco(&curproc->p_vmspace->vm_map,
|
|
obj, (vm_offset_t)cp,
|
|
(vm_offset_t)iov->iov_base);
|
|
|
|
/*
|
|
* If we get an error back, attempt
|
|
* to use copyout() instead. The
|
|
* disposable page should be freed
|
|
* automatically if we weren't able to move
|
|
* it into userland.
|
|
*/
|
|
if (error != 0)
|
|
error = copyout(cp, iov->iov_base, cnt);
|
|
} else {
|
|
error = copyout(cp, iov->iov_base, cnt);
|
|
}
|
|
} else {
|
|
error = copyin(iov->iov_base, cp, cnt);
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
uiomoveco(void *cp, int n, struct uio *uio, struct vm_object *obj,
|
|
int disposable)
|
|
{
|
|
struct iovec *iov;
|
|
u_int cnt;
|
|
int error;
|
|
|
|
KASSERT(uio->uio_rw == UIO_READ || uio->uio_rw == UIO_WRITE,
|
|
("uiomoveco: mode"));
|
|
KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread,
|
|
("uiomoveco proc"));
|
|
|
|
while (n > 0 && uio->uio_resid) {
|
|
iov = uio->uio_iov;
|
|
cnt = iov->iov_len;
|
|
if (cnt == 0) {
|
|
uio->uio_iov++;
|
|
uio->uio_iovcnt--;
|
|
continue;
|
|
}
|
|
if (cnt > n)
|
|
cnt = n;
|
|
|
|
switch (uio->uio_segflg) {
|
|
|
|
case UIO_USERSPACE:
|
|
if (ticks - PCPU_GET(switchticks) >= hogticks)
|
|
uio_yield();
|
|
|
|
error = userspaceco(cp, cnt, uio, obj, disposable);
|
|
|
|
if (error)
|
|
return (error);
|
|
break;
|
|
|
|
case UIO_SYSSPACE:
|
|
if (uio->uio_rw == UIO_READ)
|
|
bcopy(cp, iov->iov_base, cnt);
|
|
else
|
|
bcopy(iov->iov_base, cp, cnt);
|
|
break;
|
|
case UIO_NOCOPY:
|
|
break;
|
|
}
|
|
iov->iov_base = (char *)iov->iov_base + cnt;
|
|
iov->iov_len -= cnt;
|
|
uio->uio_resid -= cnt;
|
|
uio->uio_offset += cnt;
|
|
cp = (char *)cp + cnt;
|
|
n -= cnt;
|
|
}
|
|
return (0);
|
|
}
|
|
#endif /* ZERO_COPY_SOCKETS */
|
|
|
|
/*
|
|
* Give next character to user as result of read.
|
|
*/
|
|
int
|
|
ureadc(int c, struct uio *uio)
|
|
{
|
|
struct iovec *iov;
|
|
char *iov_base;
|
|
|
|
again:
|
|
if (uio->uio_iovcnt == 0 || uio->uio_resid == 0)
|
|
panic("ureadc");
|
|
iov = uio->uio_iov;
|
|
if (iov->iov_len == 0) {
|
|
uio->uio_iovcnt--;
|
|
uio->uio_iov++;
|
|
goto again;
|
|
}
|
|
switch (uio->uio_segflg) {
|
|
|
|
case UIO_USERSPACE:
|
|
if (subyte(iov->iov_base, c) < 0)
|
|
return (EFAULT);
|
|
break;
|
|
|
|
case UIO_SYSSPACE:
|
|
iov_base = iov->iov_base;
|
|
*iov_base = c;
|
|
iov->iov_base = iov_base;
|
|
break;
|
|
|
|
case UIO_NOCOPY:
|
|
break;
|
|
}
|
|
iov->iov_base = (char *)iov->iov_base + 1;
|
|
iov->iov_len--;
|
|
uio->uio_resid--;
|
|
uio->uio_offset++;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* General routine to allocate a hash table.
|
|
*/
|
|
void *
|
|
hashinit(int elements, struct malloc_type *type, u_long *hashmask)
|
|
{
|
|
long hashsize;
|
|
LIST_HEAD(generic, generic) *hashtbl;
|
|
int i;
|
|
|
|
if (elements <= 0)
|
|
panic("hashinit: bad elements");
|
|
for (hashsize = 1; hashsize <= elements; hashsize <<= 1)
|
|
continue;
|
|
hashsize >>= 1;
|
|
hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl), type, M_WAITOK);
|
|
for (i = 0; i < hashsize; i++)
|
|
LIST_INIT(&hashtbl[i]);
|
|
*hashmask = hashsize - 1;
|
|
return (hashtbl);
|
|
}
|
|
|
|
void
|
|
hashdestroy(void *vhashtbl, struct malloc_type *type, u_long hashmask)
|
|
{
|
|
LIST_HEAD(generic, generic) *hashtbl, *hp;
|
|
|
|
hashtbl = vhashtbl;
|
|
for (hp = hashtbl; hp <= &hashtbl[hashmask]; hp++)
|
|
if (!LIST_EMPTY(hp))
|
|
panic("hashdestroy: hash not empty");
|
|
free(hashtbl, type);
|
|
}
|
|
|
|
static int primes[] = { 1, 13, 31, 61, 127, 251, 509, 761, 1021, 1531, 2039,
|
|
2557, 3067, 3583, 4093, 4603, 5119, 5623, 6143, 6653,
|
|
7159, 7673, 8191, 12281, 16381, 24571, 32749 };
|
|
#define NPRIMES (sizeof(primes) / sizeof(primes[0]))
|
|
|
|
/*
|
|
* General routine to allocate a prime number sized hash table.
|
|
*/
|
|
void *
|
|
phashinit(int elements, struct malloc_type *type, u_long *nentries)
|
|
{
|
|
long hashsize;
|
|
LIST_HEAD(generic, generic) *hashtbl;
|
|
int i;
|
|
|
|
if (elements <= 0)
|
|
panic("phashinit: bad elements");
|
|
for (i = 1, hashsize = primes[1]; hashsize <= elements;) {
|
|
i++;
|
|
if (i == NPRIMES)
|
|
break;
|
|
hashsize = primes[i];
|
|
}
|
|
hashsize = primes[i - 1];
|
|
hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl), type, M_WAITOK);
|
|
for (i = 0; i < hashsize; i++)
|
|
LIST_INIT(&hashtbl[i]);
|
|
*nentries = hashsize;
|
|
return (hashtbl);
|
|
}
|
|
|
|
void
|
|
uio_yield(void)
|
|
{
|
|
struct thread *td;
|
|
|
|
td = curthread;
|
|
mtx_lock_spin(&sched_lock);
|
|
DROP_GIANT();
|
|
sched_prio(td, td->td_ksegrp->kg_user_pri); /* XXXKSE */
|
|
mi_switch(SW_INVOL, NULL);
|
|
mtx_unlock_spin(&sched_lock);
|
|
PICKUP_GIANT();
|
|
}
|
|
|
|
int
|
|
copyinfrom(const void * __restrict src, void * __restrict dst, size_t len,
|
|
int seg)
|
|
{
|
|
int error = 0;
|
|
|
|
switch (seg) {
|
|
case UIO_USERSPACE:
|
|
error = copyin(src, dst, len);
|
|
break;
|
|
case UIO_SYSSPACE:
|
|
bcopy(src, dst, len);
|
|
break;
|
|
default:
|
|
panic("copyinfrom: bad seg %d\n", seg);
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
copyinstrfrom(const void * __restrict src, void * __restrict dst, size_t len,
|
|
size_t * __restrict copied, int seg)
|
|
{
|
|
int error = 0;
|
|
|
|
switch (seg) {
|
|
case UIO_USERSPACE:
|
|
error = copyinstr(src, dst, len, copied);
|
|
break;
|
|
case UIO_SYSSPACE:
|
|
error = copystr(src, dst, len, copied);
|
|
break;
|
|
default:
|
|
panic("copyinstrfrom: bad seg %d\n", seg);
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
uiofromiov(struct iovec *iovp, u_int iovcnt, struct uio *uio)
|
|
{
|
|
struct iovec *iov;
|
|
u_int iovlen;
|
|
int error, i;
|
|
|
|
/* note: can't use iovlen until iovcnt is validated */
|
|
iovlen = iovcnt * sizeof (struct iovec);
|
|
if (iovcnt > UIO_MAXIOV) {
|
|
error = EINVAL;
|
|
goto done;
|
|
}
|
|
MALLOC(iov, struct iovec *, iovlen, M_IOV, M_WAITOK);
|
|
uio->uio_iov = iov;
|
|
uio->uio_iovcnt = iovcnt;
|
|
uio->uio_segflg = UIO_USERSPACE;
|
|
uio->uio_offset = -1;
|
|
if ((error = copyin(iovp, iov, iovlen)))
|
|
goto done;
|
|
uio->uio_resid = 0;
|
|
for (i = 0; i < iovcnt; i++) {
|
|
if (iov->iov_len > INT_MAX - uio->uio_resid) {
|
|
error = EINVAL;
|
|
goto done;
|
|
}
|
|
uio->uio_resid += iov->iov_len;
|
|
iov++;
|
|
}
|
|
|
|
done:
|
|
if (error && uio->uio_iov) {
|
|
FREE(uio->uio_iov, M_IOV);
|
|
uio->uio_iov = NULL;
|
|
}
|
|
return (error);
|
|
|
|
}
|