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Remove zero-copy sockets code. It only worked for anonymous memory,

Browse Source 
and the equivalent functionality is now provided by sendfile(2) over
posix shared memory filedescriptor.

Remove the cow member of struct vm_page, and rearrange the remaining
members.  While there, make hold_count unsigned.

Requested and reviewed by:	alc
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
Approved by:	re (delphij)
This commit is contained in:
kib 2013-09-16 06:25:54 +00:00
parent 9867f4e99b
commit 6796656333
12 changed files with 12 additions and 494 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
sys/conf/NOTES
View File

@ -996,21 +996,6 @@ options TCP_SIGNATURE #include support for RFC 2385
# a smooth scheduling of the traffic.
options DUMMYNET
# "Zero copy" sockets support is split into the send and receive path
# which operate very differently.
# For the send path the VM page with the data is wired into the kernel
# and marked as COW (copy-on-write). If the application touches the
# data while it is still in the send socket buffer the page is copied
# and divorced from its kernel wiring (no longer zero copy).
# The receive side requires explicit NIC driver support to create
# disposable pages which are flipped from kernel to user-space VM.
# See zero_copy(9) for more details.
# XXX: The COW based send mechanism is not safe and may result in
# kernel crashes.
# XXX: None of the current NIC drivers support disposable pages.
options SOCKET_SEND_COW
options SOCKET_RECV_PFLIP
#####################################################################
# FILESYSTEM OPTIONS

2
sys/conf/options
View File

@ -528,8 +528,6 @@ NGATM_CCATM opt_netgraph.h
# DRM options
DRM_DEBUG opt_drm.h
SOCKET_SEND_COW opt_zero.h
SOCKET_RECV_PFLIP opt_zero.h
TI_SF_BUF_JUMBO opt_ti.h
TI_JUMBO_HDRSPLIT opt_ti.h

171
sys/kern/subr_uio.c
View File

@ -37,8 +37,6 @@
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_zero.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
@ -58,84 +56,12 @@ __FBSDID("$FreeBSD$");
#include <vm/vm_page.h>
#include <vm/vm_pageout.h>
#include <vm/vm_map.h>
#ifdef SOCKET_SEND_COW
#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)");
static int uiomove_faultflag(void *cp, int n, struct uio *uio, int nofault);
#ifdef SOCKET_SEND_COW
/* Declared in uipc_socket.c */
extern int so_zero_copy_receive;
/*
* Identify the physical page mapped at the given kernel virtual
* address. Insert this physical page into the given address space at
* the given virtual address, replacing the physical page, if any,
* that already exists there.
*/
static int
vm_pgmoveco(vm_map_t mapa, 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;
vm_prot_t prot;
boolean_t wired;
KASSERT((uaddr & PAGE_MASK) == 0,
("vm_pgmoveco: uaddr is not page aligned"));
/*
* Herein the physical page is validated and dirtied. It is
* unwired in sf_buf_mext().
*/
kern_pg = PHYS_TO_VM_PAGE(vtophys(kaddr));
kern_pg->valid = VM_PAGE_BITS_ALL;
KASSERT(kern_pg->queue == PQ_NONE && kern_pg->wire_count == 1,
("vm_pgmoveco: kern_pg is not correctly wired"));
if ((vm_map_lookup(&map, uaddr,
VM_PROT_WRITE, &entry, &uobject,
&upindex, &prot, &wired)) != KERN_SUCCESS) {
return(EFAULT);
}
VM_OBJECT_WLOCK(uobject);
retry:
if ((user_pg = vm_page_lookup(uobject, upindex)) != NULL) {
if (vm_page_sleep_if_busy(user_pg, "vm_pgmoveco"))
goto retry;
vm_page_lock(user_pg);
pmap_remove_all(user_pg);
vm_page_free(user_pg);
vm_page_unlock(user_pg);
} else {
/*
* Even if a physical page does not exist in the
* object chain's first object, a physical page from a
* backing object may be mapped read only.
*/
if (uobject->backing_object != NULL)
pmap_remove(map->pmap, uaddr, uaddr + PAGE_SIZE);
}
if (vm_page_insert(kern_pg, uobject, upindex)) {
VM_OBJECT_WUNLOCK(uobject);
VM_WAIT;
VM_OBJECT_WLOCK(uobject);
goto retry;
}
vm_page_dirty(kern_pg);
VM_OBJECT_WUNLOCK(uobject);
vm_map_lookup_done(map, entry);
return(KERN_SUCCESS);
}
#endif /* SOCKET_SEND_COW */
int
copyin_nofault(const void *udaddr, void *kaddr, size_t len)
{
@ -313,103 +239,6 @@ uiomove_frombuf(void *buf, int buflen, struct uio *uio)
return (uiomove((char *)buf + offset, n, uio));
}
#ifdef SOCKET_RECV_PFLIP
/*
* Experimental support for zero-copy I/O
*/
static int
userspaceco(void *cp, u_int cnt, struct uio *uio, int disposable)
{
struct iovec *iov;
int error;
iov = uio->uio_iov;
if (uio->uio_rw == UIO_READ) {
if ((so_zero_copy_receive != 0)
&& ((cnt & PAGE_MASK) == 0)
&& ((((intptr_t) iov->iov_base) & PAGE_MASK) == 0)
&& ((uio->uio_offset & PAGE_MASK) == 0)
&& ((((intptr_t) cp) & PAGE_MASK) == 0)
&& (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,
(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, 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:
maybe_yield();
error = userspaceco(cp, cnt, uio, 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 /* SOCKET_RECV_PFLIP */
/*
* Give next character to user as result of read.
*/

167
sys/kern/uipc_socket.c
View File

@ -105,7 +105,6 @@ __FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_zero.h"
#include "opt_compat.h"
#include <sys/param.h>
@ -221,21 +220,6 @@ static int numopensockets;
SYSCTL_INT(_kern_ipc, OID_AUTO, numopensockets, CTLFLAG_RD,
&numopensockets, 0, "Number of open sockets");
#if defined(SOCKET_SEND_COW) || defined(SOCKET_RECV_PFLIP)
SYSCTL_NODE(_kern_ipc, OID_AUTO, zero_copy, CTLFLAG_RD, 0,
"Zero copy controls");
#ifdef SOCKET_RECV_PFLIP
int so_zero_copy_receive = 1;
SYSCTL_INT(_kern_ipc_zero_copy, OID_AUTO, receive, CTLFLAG_RW,
&so_zero_copy_receive, 0, "Enable zero copy receive");
#endif
#ifdef SOCKET_SEND_COW
int so_zero_copy_send = 1;
SYSCTL_INT(_kern_ipc_zero_copy, OID_AUTO, send, CTLFLAG_RW,
&so_zero_copy_send, 0, "Enable zero copy send");
#endif /* SOCKET_SEND_COW */
#endif /* SOCKET_SEND_COW || SOCKET_RECV_PFLIP */
/*
* accept_mtx locks down per-socket fields relating to accept queues. See
* socketvar.h for an annotation of the protected fields of struct socket.
@ -978,113 +962,6 @@ sodisconnect(struct socket *so)
return (error);
}
#ifdef SOCKET_SEND_COW
struct so_zerocopy_stats{
int size_ok;
int align_ok;
int found_ifp;
};
struct so_zerocopy_stats so_zerocp_stats = {0,0,0};
/*
* sosend_copyin() is only used if zero copy sockets are enabled. Otherwise
* sosend_dgram() and sosend_generic() use m_uiotombuf().
*
* sosend_copyin() accepts a uio and prepares an mbuf chain holding part or
* all of the data referenced by the uio. If desired, it uses zero-copy.
* *space will be updated to reflect data copied in.
*
* NB: If atomic I/O is requested, the caller must already have checked that
* space can hold resid bytes.
*
* NB: In the event of an error, the caller may need to free the partial
* chain pointed to by *mpp. The contents of both *uio and *space may be
* modified even in the case of an error.
*/
static int
sosend_copyin(struct uio *uio, struct mbuf **retmp, int atomic, long *space,
int flags)
{
struct mbuf *m, **mp, *top;
long len;
ssize_t resid;
int error;
int cow_send;
*retmp = top = NULL;
mp = &top;
len = 0;
resid = uio->uio_resid;
error = 0;
do {
cow_send = 0;
if (resid >= MINCLSIZE) {
if (top == NULL) {
m = m_gethdr(M_WAITOK, MT_DATA);
m->m_pkthdr.len = 0;
m->m_pkthdr.rcvif = NULL;
} else
m = m_get(M_WAITOK, MT_DATA);
if (so_zero_copy_send &&
resid >= PAGE_SIZE &&
*space >= PAGE_SIZE &&
uio->uio_iov->iov_len >= PAGE_SIZE) {
so_zerocp_stats.size_ok++;
so_zerocp_stats.align_ok++;
cow_send = socow_setup(m, uio);
len = cow_send;
}
if (!cow_send) {
m_clget(m, M_WAITOK);
len = min(min(MCLBYTES, resid), *space);
}
} else {
if (top == NULL) {
m = m_gethdr(M_WAITOK, MT_DATA);
m->m_pkthdr.len = 0;
m->m_pkthdr.rcvif = NULL;
len = min(min(MHLEN, resid), *space);
/*
* For datagram protocols, leave room
* for protocol headers in first mbuf.
*/
if (atomic && m && len < MHLEN)
MH_ALIGN(m, len);
} else {
m = m_get(M_WAITOK, MT_DATA);
len = min(min(MLEN, resid), *space);
}
}
if (m == NULL) {
error = ENOBUFS;
goto out;
}
*space -= len;
if (cow_send)
error = 0;
else
error = uiomove(mtod(m, void *), (int)len, uio);
resid = uio->uio_resid;
m->m_len = len;
*mp = m;
top->m_pkthdr.len += len;
if (error)
goto out;
mp = &m->m_next;
if (resid <= 0) {
if (flags & MSG_EOR)
top->m_flags |= M_EOR;
break;
}
} while (*space > 0 && atomic);
out:
*retmp = top;
return (error);
}
#endif /* SOCKET_SEND_COW */
#define SBLOCKWAIT(f) (((f) & MSG_DONTWAIT) ? 0 : SBL_WAIT)
int
@ -1094,9 +971,6 @@ sosend_dgram(struct socket *so, struct sockaddr *addr, struct uio *uio,
long space;
ssize_t resid;
int clen = 0, error, dontroute;
#ifdef SOCKET_SEND_COW
int atomic = sosendallatonce(so) || top;
#endif
KASSERT(so->so_type == SOCK_DGRAM, ("sosend_dgram: !SOCK_DGRAM"));
KASSERT(so->so_proto->pr_flags & PR_ATOMIC,
@ -1179,11 +1053,6 @@ sosend_dgram(struct socket *so, struct sockaddr *addr, struct uio *uio,
if (flags & MSG_EOR)
top->m_flags |= M_EOR;
} else {
#ifdef SOCKET_SEND_COW
error = sosend_copyin(uio, &top, atomic, &space, flags);
if (error)
goto out;
#else
/*
* Copy the data from userland into a mbuf chain.
* If no data is to be copied in, a single empty mbuf
@ -1196,7 +1065,6 @@ sosend_dgram(struct socket *so, struct sockaddr *addr, struct uio *uio,
goto out;
}
space -= resid - uio->uio_resid;
#endif /* SOCKET_SEND_COW */
resid = uio->uio_resid;
}
KASSERT(resid == 0, ("sosend_dgram: resid != 0"));
@ -1368,12 +1236,6 @@ restart:
if (flags & MSG_EOR)
top->m_flags |= M_EOR;
} else {
#ifdef SOCKET_SEND_COW
error = sosend_copyin(uio, &top, atomic,
&space, flags);
if (error != 0)
goto release;
#else
/*
* Copy the data from userland into a mbuf
* chain. If no data is to be copied in,
@ -1388,7 +1250,6 @@ restart:
goto release;
}
space -= resid - uio->uio_resid;
#endif /* SOCKET_SEND_COW */
resid = uio->uio_resid;
}
if (dontroute) {
@ -1480,20 +1341,6 @@ soreceive_rcvoob(struct socket *so, struct uio *uio, int flags)
if (error)
goto bad;
do {
#ifdef SOCKET_RECV_PFLIP
if (so_zero_copy_receive) {
int disposable;
if ((m->m_flags & M_EXT)
&& (m->m_ext.ext_type == EXT_DISPOSABLE))
disposable = 1;
else
disposable = 0;
error = uiomoveco(mtod(m, void *),
min(uio->uio_resid, m->m_len), uio, disposable);
} else
#endif /* SOCKET_RECV_PFLIP */
error = uiomove(mtod(m, void *),
(int) min(uio->uio_resid, m->m_len), uio);
m = m_free(m);
@ -1816,20 +1663,6 @@ dontblock:
SBLASTRECORDCHK(&so->so_rcv);
SBLASTMBUFCHK(&so->so_rcv);
SOCKBUF_UNLOCK(&so->so_rcv);
#ifdef SOCKET_RECV_PFLIP
if (so_zero_copy_receive) {
int disposable;
if ((m->m_flags & M_EXT)
&& (m->m_ext.ext_type == EXT_DISPOSABLE))
disposable = 1;
else
disposable = 0;
error = uiomoveco(mtod(m, char *) + moff,
(int)len, uio, disposable);
} else
#endif /* SOCKET_RECV_PFLIP */
error = uiomove(mtod(m, char *) + moff, (int)len, uio);
SOCKBUF_LOCK(&so->so_rcv);
if (error) {

2
sys/modules/cxgb/cxgb/Makefile
View File

@ -10,7 +10,7 @@ SRCS= cxgb_mc5.c cxgb_vsc8211.c cxgb_ael1002.c cxgb_mv88e1xxx.c
SRCS+= cxgb_xgmac.c cxgb_vsc7323.c cxgb_t3_hw.c cxgb_main.c cxgb_aq100x.c
SRCS+= cxgb_sge.c cxgb_tn1010.c
SRCS+= device_if.h bus_if.h pci_if.h
SRCS+= opt_inet.h opt_inet6.h opt_zero.h opt_sched.h
SRCS+= opt_inet.h opt_inet6.h opt_sched.h
SRCS+= uipc_mvec.c
CFLAGS+= -g -DDEFAULT_JUMBO -I${CXGB}

2
sys/modules/sfxge/Makefile
View File

@ -5,7 +5,7 @@ KMOD= sfxge
SFXGE= ${.CURDIR}/../../dev/sfxge
SRCS= device_if.h bus_if.h pci_if.h
SRCS+= opt_inet.h opt_zero.h opt_sched.h
SRCS+= opt_inet.h opt_sched.h
.PATH: ${.CURDIR}/../../dev/sfxge
SRCS+= sfxge.c sfxge_dma.c sfxge_ev.c

2
sys/modules/ti/Makefile
View File

@ -3,6 +3,6 @@
.PATH: ${.CURDIR}/../../dev/ti
KMOD= if_ti
SRCS= if_ti.c device_if.h bus_if.h pci_if.h opt_ti.h opt_zero.h
SRCS= if_ti.c device_if.h bus_if.h pci_if.h opt_ti.h
.include <bsd.kmod.mk>

1
sys/sys/socketvar.h
View File

@ -325,7 +325,6 @@ int soconnect(struct socket *so, struct sockaddr *nam, struct thread *td);
int soconnectat(int fd, struct socket *so, struct sockaddr *nam,
struct thread *td);
int soconnect2(struct socket *so1, struct socket *so2);
int socow_setup(struct mbuf *m0, struct uio *uio);
int socreate(int dom, struct socket **aso, int type, int proto,
struct ucred *cred, struct thread *td);
int sodisconnect(struct socket *so);

1
sys/sys/uio.h
View File

@ -104,7 +104,6 @@ int uiomove_fromphys(struct vm_page *ma[], vm_offset_t offset, int n,
struct uio *uio);
int uiomove_nofault(void *cp, int n, struct uio *uio);
int uiomove_object(struct vm_object *obj, off_t obj_size, struct uio *uio);
int uiomoveco(void *cp, int n, struct uio *uio, int disposable);
#else /* !_KERNEL */

20
sys/vm/vm_fault.c
View File

@ -333,24 +333,6 @@ RetryFault:;
*/
fs.m = vm_page_lookup(fs.object, fs.pindex);
if (fs.m != NULL) {
/*
* check for page-based copy on write.
* We check fs.object == fs.first_object so
* as to ensure the legacy COW mechanism is
* used when the page in question is part of
* a shadow object. Otherwise, vm_page_cowfault()
* removes the page from the backing object,
* which is not what we want.
*/
vm_page_lock(fs.m);
if ((fs.m->cow) &&
(fault_type & VM_PROT_WRITE) &&
(fs.object == fs.first_object)) {
vm_page_cowfault(fs.m);
unlock_and_deallocate(&fs);
goto RetryFault;
}
/*
* Wait/Retry if the page is busy. We have to do this
* if the page is either exclusive or shared busy
@ -374,7 +356,6 @@ RetryFault:;
* likely to reclaim it.
*/
vm_page_aflag_set(fs.m, PGA_REFERENCED);
vm_page_unlock(fs.m);
if (fs.object != fs.first_object) {
if (!VM_OBJECT_TRYWLOCK(
fs.first_object)) {
@ -400,6 +381,7 @@ RetryFault:;
vm_object_deallocate(fs.first_object);
goto RetryFault;
}
vm_page_lock(fs.m);
vm_page_remque(fs.m);
vm_page_unlock(fs.m);

104
sys/vm/vm_page.c
View File

@ -674,8 +674,8 @@ vm_page_unhold(vm_page_t mem)
{
vm_page_lock_assert(mem, MA_OWNED);
KASSERT(mem->hold_count >= 1, ("vm_page_unhold: hold count < 0!!!"));
--mem->hold_count;
KASSERT(mem->hold_count >= 0, ("vm_page_unhold: hold count < 0!!!"));
if (mem->hold_count == 0 && (mem->flags & PG_UNHOLDFREE) != 0)
vm_page_free_toq(mem);
}
@ -3108,108 +3108,6 @@ vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line)
}
#endif
int so_zerocp_fullpage = 0;
/*
* Replace the given page with a copy. The copied page assumes
* the portion of the given page's "wire_count" that is not the
* responsibility of this copy-on-write mechanism.
*
* The object containing the given page must have a non-zero
* paging-in-progress count and be locked.
*/
void
vm_page_cowfault(vm_page_t m)
{
vm_page_t mnew;
vm_object_t object;
vm_pindex_t pindex;
vm_page_lock_assert(m, MA_OWNED);
object = m->object;
VM_OBJECT_ASSERT_WLOCKED(object);
KASSERT(object->paging_in_progress != 0,
("vm_page_cowfault: object %p's paging-in-progress count is zero.",
object));
pindex = m->pindex;
retry_alloc:
mnew = vm_page_alloc(NULL, pindex, VM_ALLOC_NORMAL | VM_ALLOC_NOOBJ);
if (mnew == NULL) {
vm_page_unlock(m);
VM_OBJECT_WUNLOCK(object);
VM_WAIT;
VM_OBJECT_WLOCK(object);
if (m == vm_page_lookup(object, pindex)) {
vm_page_lock(m);
goto retry_alloc;
} else {
/*
* Page disappeared during the wait.
*/
return;
}
}
if (m->cow == 0) {
/*
* check to see if we raced with an xmit complete when
* waiting to allocate a page. If so, put things back
* the way they were
*/
vm_page_unlock(m);
vm_page_lock(mnew);
vm_page_free(mnew);
vm_page_unlock(mnew);
} else { /* clear COW & copy page */
pmap_remove_all(m);
mnew->object = object;
if (object->memattr != VM_MEMATTR_DEFAULT &&
(object->flags & OBJ_FICTITIOUS) == 0)
pmap_page_set_memattr(mnew, object->memattr);
if (vm_page_replace(mnew, object, pindex) != m)
panic("vm_page_cowfault: invalid page replacement");
if (!so_zerocp_fullpage)
pmap_copy_page(m, mnew);
mnew->valid = VM_PAGE_BITS_ALL;
vm_page_dirty(mnew);
mnew->wire_count = m->wire_count - m->cow;
m->wire_count = m->cow;
vm_page_unlock(m);
}
}
void
vm_page_cowclear(vm_page_t m)
{
vm_page_lock_assert(m, MA_OWNED);
if (m->cow) {
m->cow--;
/*
* let vm_fault add back write permission lazily
*/
}
/*
* sf_buf_free() will free the page, so we needn't do it here
*/
}
int
vm_page_cowsetup(vm_page_t m)
{
vm_page_lock_assert(m, MA_OWNED);
if ((m->flags & PG_FICTITIOUS) != 0 ||
(m->oflags & VPO_UNMANAGED) != 0 ||
m->cow == USHRT_MAX - 1 || !VM_OBJECT_TRYWLOCK(m->object))
return (EBUSY);
m->cow++;
pmap_remove_write(m);
VM_OBJECT_WUNLOCK(m->object);
return (0);
}
#ifdef INVARIANTS
void
vm_page_object_lock_assert(vm_page_t m)

19
sys/vm/vm_page.h
View File

@ -142,23 +142,21 @@ struct vm_page {
vm_pindex_t pindex; /* offset into object (O,P) */
vm_paddr_t phys_addr; /* physical address of page */
struct md_page md; /* machine dependant stuff */
uint8_t queue; /* page queue index (P,Q) */
int8_t segind;
short hold_count; /* page hold count (P) */
uint8_t order; /* index of the buddy queue */
uint8_t pool;
u_short cow; /* page cow mapping count (P) */
u_int wire_count; /* wired down maps refs (P) */
volatile u_int busy_lock; /* busy owners lock */
uint16_t hold_count; /* page hold count (P) */
uint16_t flags; /* page PG_* flags (P) */
uint8_t aflags; /* access is atomic */
uint8_t oflags; /* page VPO_* flags (O) */
uint16_t flags; /* page PG_* flags (P) */
uint8_t queue; /* page queue index (P,Q) */
int8_t segind;
uint8_t order; /* index of the buddy queue */
uint8_t pool;
u_char act_count; /* page usage count (P) */
u_char __pad0; /* unused padding */
/* NOTE that these must support one bit per DEV_BSIZE in a page */
/* so, on normal X86 kernels, they must be at least 8 bits wide */
vm_page_bits_t valid; /* map of valid DEV_BSIZE chunks (O) */
vm_page_bits_t dirty; /* map of dirty DEV_BSIZE chunks (M) */
volatile u_int busy_lock; /* busy owners lock */
};
/*
@ -482,9 +480,6 @@ vm_page_bits_t vm_page_bits(int base, int size);
void vm_page_zero_invalid(vm_page_t m, boolean_t setvalid);
void vm_page_free_toq(vm_page_t m);
void vm_page_zero_idle_wakeup(void);
void vm_page_cowfault (vm_page_t);
int vm_page_cowsetup(vm_page_t);
void vm_page_cowclear (vm_page_t);
void vm_page_dirty_KBI(vm_page_t m);
void vm_page_lock_KBI(vm_page_t m, const char *file, int line);