freebsd-dev/sys/kern/uipc_syscalls.c
Poul-Henning Kamp 124e4c3be8 Introduce an alias for FILEDESC_{UN}LOCK() with the suffix _FAST.
Use this in all the places where sleeping with the lock held is not
an issue.

The distinction will become significant once we finalize the exact
lock-type to use for this kind of case.
2004-11-13 11:53:02 +00:00

2122 lines
43 KiB
C

/*
* Copyright (c) 1982, 1986, 1989, 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* sendfile(2) and related extensions:
* Copyright (c) 1998, David Greenman. All rights reserved.
*
* 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.
*
* @(#)uipc_syscalls.c 8.4 (Berkeley) 2/21/94
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_compat.h"
#include "opt_ktrace.h"
#include "opt_mac.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mac.h>
#include <sys/mutex.h>
#include <sys/sysproto.h>
#include <sys/malloc.h>
#include <sys/filedesc.h>
#include <sys/event.h>
#include <sys/proc.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/filio.h>
#include <sys/mount.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/sf_buf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/signalvar.h>
#include <sys/syscallsubr.h>
#include <sys/sysctl.h>
#include <sys/uio.h>
#include <sys/vnode.h>
#ifdef KTRACE
#include <sys/ktrace.h>
#endif
#include <vm/vm.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pageout.h>
#include <vm/vm_kern.h>
#include <vm/vm_extern.h>
static int sendit(struct thread *td, int s, struct msghdr *mp, int flags);
static int recvit(struct thread *td, int s, struct msghdr *mp, void *namelenp);
static int accept1(struct thread *td, struct accept_args *uap, int compat);
static int do_sendfile(struct thread *td, struct sendfile_args *uap, int compat);
static int getsockname1(struct thread *td, struct getsockname_args *uap,
int compat);
static int getpeername1(struct thread *td, struct getpeername_args *uap,
int compat);
/*
* NSFBUFS-related variables and associated sysctls
*/
int nsfbufs;
int nsfbufspeak;
int nsfbufsused;
SYSCTL_DECL(_kern_ipc);
SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufs, CTLFLAG_RDTUN, &nsfbufs, 0,
"Maximum number of sendfile(2) sf_bufs available");
SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufspeak, CTLFLAG_RD, &nsfbufspeak, 0,
"Number of sendfile(2) sf_bufs at peak usage");
SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufsused, CTLFLAG_RD, &nsfbufsused, 0,
"Number of sendfile(2) sf_bufs in use");
/*
* Convert a user file descriptor to a kernel file entry. A reference on the
* file entry is held upon returning. This is lighter weight than
* fgetsock(), which bumps the socket reference drops the file reference
* count instead, as this approach avoids several additional mutex operations
* associated with the additional reference count.
*/
static int
getsock(struct filedesc *fdp, int fd, struct file **fpp)
{
struct file *fp;
int error;
fp = NULL;
if (fdp == NULL)
error = EBADF;
else {
FILEDESC_LOCK_FAST(fdp);
fp = fget_locked(fdp, fd);
if (fp == NULL)
error = EBADF;
else if (fp->f_type != DTYPE_SOCKET) {
fp = NULL;
error = ENOTSOCK;
} else {
fhold(fp);
error = 0;
}
FILEDESC_UNLOCK_FAST(fdp);
}
*fpp = fp;
return (error);
}
/*
* System call interface to the socket abstraction.
*/
#if defined(COMPAT_43)
#define COMPAT_OLDSOCK
#endif
/*
* MPSAFE
*/
int
socket(td, uap)
struct thread *td;
register struct socket_args /* {
int domain;
int type;
int protocol;
} */ *uap;
{
struct filedesc *fdp;
struct socket *so;
struct file *fp;
int fd, error;
fdp = td->td_proc->p_fd;
error = falloc(td, &fp, &fd);
if (error)
return (error);
/* An extra reference on `fp' has been held for us by falloc(). */
NET_LOCK_GIANT();
error = socreate(uap->domain, &so, uap->type, uap->protocol,
td->td_ucred, td);
NET_UNLOCK_GIANT();
if (error) {
fdclose(fdp, fp, fd, td);
} else {
FILEDESC_LOCK_FAST(fdp);
fp->f_data = so; /* already has ref count */
fp->f_flag = FREAD|FWRITE;
fp->f_ops = &socketops;
fp->f_type = DTYPE_SOCKET;
FILEDESC_UNLOCK_FAST(fdp);
td->td_retval[0] = fd;
}
fdrop(fp, td);
return (error);
}
/*
* MPSAFE
*/
/* ARGSUSED */
int
bind(td, uap)
struct thread *td;
register struct bind_args /* {
int s;
caddr_t name;
int namelen;
} */ *uap;
{
struct sockaddr *sa;
int error;
if ((error = getsockaddr(&sa, uap->name, uap->namelen)) != 0)
return (error);
return (kern_bind(td, uap->s, sa));
}
int
kern_bind(td, fd, sa)
struct thread *td;
int fd;
struct sockaddr *sa;
{
struct socket *so;
struct file *fp;
int error;
NET_LOCK_GIANT();
error = getsock(td->td_proc->p_fd, fd, &fp);
if (error)
goto done2;
so = fp->f_data;
#ifdef MAC
SOCK_LOCK(so);
error = mac_check_socket_bind(td->td_ucred, so, sa);
SOCK_UNLOCK(so);
if (error)
goto done1;
#endif
error = sobind(so, sa, td);
#ifdef MAC
done1:
#endif
fdrop(fp, td);
done2:
NET_UNLOCK_GIANT();
FREE(sa, M_SONAME);
return (error);
}
/*
* MPSAFE
*/
/* ARGSUSED */
int
listen(td, uap)
struct thread *td;
register struct listen_args /* {
int s;
int backlog;
} */ *uap;
{
struct socket *so;
struct file *fp;
int error;
NET_LOCK_GIANT();
error = getsock(td->td_proc->p_fd, uap->s, &fp);
if (error == 0) {
so = fp->f_data;
#ifdef MAC
SOCK_LOCK(so);
error = mac_check_socket_listen(td->td_ucred, so);
SOCK_UNLOCK(so);
if (error)
goto done;
#endif
error = solisten(so, uap->backlog, td);
#ifdef MAC
done:
#endif
fdrop(fp, td);
}
NET_UNLOCK_GIANT();
return(error);
}
/*
* accept1()
* MPSAFE
*/
static int
accept1(td, uap, compat)
struct thread *td;
register struct accept_args /* {
int s;
struct sockaddr * __restrict name;
socklen_t * __restrict anamelen;
} */ *uap;
int compat;
{
struct filedesc *fdp;
struct file *nfp = NULL;
struct sockaddr *sa = NULL;
socklen_t namelen;
int error;
struct socket *head, *so;
int fd;
u_int fflag;
pid_t pgid;
int tmp;
fdp = td->td_proc->p_fd;
if (uap->name) {
error = copyin(uap->anamelen, &namelen, sizeof (namelen));
if(error)
return (error);
if (namelen < 0)
return (EINVAL);
}
NET_LOCK_GIANT();
error = fgetsock(td, uap->s, &head, &fflag);
if (error)
goto done2;
if ((head->so_options & SO_ACCEPTCONN) == 0) {
error = EINVAL;
goto done;
}
error = falloc(td, &nfp, &fd);
if (error)
goto done;
ACCEPT_LOCK();
if ((head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->so_comp)) {
ACCEPT_UNLOCK();
error = EWOULDBLOCK;
goto noconnection;
}
while (TAILQ_EMPTY(&head->so_comp) && head->so_error == 0) {
if (head->so_rcv.sb_state & SBS_CANTRCVMORE) {
head->so_error = ECONNABORTED;
break;
}
error = msleep(&head->so_timeo, &accept_mtx, PSOCK | PCATCH,
"accept", 0);
if (error) {
ACCEPT_UNLOCK();
goto noconnection;
}
}
if (head->so_error) {
error = head->so_error;
head->so_error = 0;
ACCEPT_UNLOCK();
goto noconnection;
}
so = TAILQ_FIRST(&head->so_comp);
KASSERT(!(so->so_qstate & SQ_INCOMP), ("accept1: so SQ_INCOMP"));
KASSERT(so->so_qstate & SQ_COMP, ("accept1: so not SQ_COMP"));
/*
* Before changing the flags on the socket, we have to bump the
* reference count. Otherwise, if the protocol calls sofree(),
* the socket will be released due to a zero refcount.
*/
SOCK_LOCK(so);
soref(so); /* file descriptor reference */
SOCK_UNLOCK(so);
TAILQ_REMOVE(&head->so_comp, so, so_list);
head->so_qlen--;
so->so_state |= (head->so_state & SS_NBIO);
so->so_qstate &= ~SQ_COMP;
so->so_head = NULL;
ACCEPT_UNLOCK();
/* An extra reference on `nfp' has been held for us by falloc(). */
td->td_retval[0] = fd;
/* connection has been removed from the listen queue */
KNOTE_UNLOCKED(&head->so_rcv.sb_sel.si_note, 0);
pgid = fgetown(&head->so_sigio);
if (pgid != 0)
fsetown(pgid, &so->so_sigio);
FILE_LOCK(nfp);
nfp->f_data = so; /* nfp has ref count from falloc */
nfp->f_flag = fflag;
nfp->f_ops = &socketops;
nfp->f_type = DTYPE_SOCKET;
FILE_UNLOCK(nfp);
/* Sync socket nonblocking/async state with file flags */
tmp = fflag & FNONBLOCK;
(void) fo_ioctl(nfp, FIONBIO, &tmp, td->td_ucred, td);
tmp = fflag & FASYNC;
(void) fo_ioctl(nfp, FIOASYNC, &tmp, td->td_ucred, td);
sa = 0;
error = soaccept(so, &sa);
if (error) {
/*
* return a namelen of zero for older code which might
* ignore the return value from accept.
*/
if (uap->name != NULL) {
namelen = 0;
(void) copyout(&namelen,
uap->anamelen, sizeof(*uap->anamelen));
}
goto noconnection;
}
if (sa == NULL) {
namelen = 0;
if (uap->name)
goto gotnoname;
error = 0;
goto done;
}
if (uap->name) {
/* check sa_len before it is destroyed */
if (namelen > sa->sa_len)
namelen = sa->sa_len;
#ifdef COMPAT_OLDSOCK
if (compat)
((struct osockaddr *)sa)->sa_family =
sa->sa_family;
#endif
error = copyout(sa, uap->name, (u_int)namelen);
if (!error)
gotnoname:
error = copyout(&namelen,
uap->anamelen, sizeof (*uap->anamelen));
}
noconnection:
if (sa)
FREE(sa, M_SONAME);
/*
* close the new descriptor, assuming someone hasn't ripped it
* out from under us.
*/
if (error)
fdclose(fdp, nfp, fd, td);
/*
* Release explicitly held references before returning.
*/
done:
if (nfp != NULL)
fdrop(nfp, td);
fputsock(head);
done2:
NET_UNLOCK_GIANT();
return (error);
}
/*
* MPSAFE (accept1() is MPSAFE)
*/
int
accept(td, uap)
struct thread *td;
struct accept_args *uap;
{
return (accept1(td, uap, 0));
}
#ifdef COMPAT_OLDSOCK
/*
* MPSAFE (accept1() is MPSAFE)
*/
int
oaccept(td, uap)
struct thread *td;
struct accept_args *uap;
{
return (accept1(td, uap, 1));
}
#endif /* COMPAT_OLDSOCK */
/*
* MPSAFE
*/
/* ARGSUSED */
int
connect(td, uap)
struct thread *td;
register struct connect_args /* {
int s;
caddr_t name;
int namelen;
} */ *uap;
{
struct sockaddr *sa;
int error;
error = getsockaddr(&sa, uap->name, uap->namelen);
if (error)
return (error);
return (kern_connect(td, uap->s, sa));
}
int
kern_connect(td, fd, sa)
struct thread *td;
int fd;
struct sockaddr *sa;
{
struct socket *so;
struct file *fp;
int error, s;
int interrupted = 0;
NET_LOCK_GIANT();
error = getsock(td->td_proc->p_fd, fd, &fp);
if (error)
goto done2;
so = fp->f_data;
if (so->so_state & SS_ISCONNECTING) {
error = EALREADY;
goto done1;
}
#ifdef MAC
SOCK_LOCK(so);
error = mac_check_socket_connect(td->td_ucred, so, sa);
SOCK_UNLOCK(so);
if (error)
goto bad;
#endif
error = soconnect(so, sa, td);
if (error)
goto bad;
if ((so->so_state & SS_NBIO) && (so->so_state & SS_ISCONNECTING)) {
error = EINPROGRESS;
goto done1;
}
s = splnet();
SOCK_LOCK(so);
while ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) {
error = msleep(&so->so_timeo, SOCK_MTX(so), PSOCK | PCATCH,
"connec", 0);
if (error) {
if (error == EINTR || error == ERESTART)
interrupted = 1;
break;
}
}
if (error == 0) {
error = so->so_error;
so->so_error = 0;
}
SOCK_UNLOCK(so);
splx(s);
bad:
if (!interrupted)
so->so_state &= ~SS_ISCONNECTING;
if (error == ERESTART)
error = EINTR;
done1:
fdrop(fp, td);
done2:
NET_UNLOCK_GIANT();
FREE(sa, M_SONAME);
return (error);
}
/*
* MPSAFE
*/
int
socketpair(td, uap)
struct thread *td;
register struct socketpair_args /* {
int domain;
int type;
int protocol;
int *rsv;
} */ *uap;
{
register struct filedesc *fdp = td->td_proc->p_fd;
struct file *fp1, *fp2;
struct socket *so1, *so2;
int fd, error, sv[2];
NET_LOCK_GIANT();
error = socreate(uap->domain, &so1, uap->type, uap->protocol,
td->td_ucred, td);
if (error)
goto done2;
error = socreate(uap->domain, &so2, uap->type, uap->protocol,
td->td_ucred, td);
if (error)
goto free1;
/* On success extra reference to `fp1' and 'fp2' is set by falloc. */
error = falloc(td, &fp1, &fd);
if (error)
goto free2;
sv[0] = fd;
fp1->f_data = so1; /* so1 already has ref count */
error = falloc(td, &fp2, &fd);
if (error)
goto free3;
fp2->f_data = so2; /* so2 already has ref count */
sv[1] = fd;
error = soconnect2(so1, so2);
if (error)
goto free4;
if (uap->type == SOCK_DGRAM) {
/*
* Datagram socket connection is asymmetric.
*/
error = soconnect2(so2, so1);
if (error)
goto free4;
}
FILE_LOCK(fp1);
fp1->f_flag = FREAD|FWRITE;
fp1->f_ops = &socketops;
fp1->f_type = DTYPE_SOCKET;
FILE_UNLOCK(fp1);
FILE_LOCK(fp2);
fp2->f_flag = FREAD|FWRITE;
fp2->f_ops = &socketops;
fp2->f_type = DTYPE_SOCKET;
FILE_UNLOCK(fp2);
error = copyout(sv, uap->rsv, 2 * sizeof (int));
fdrop(fp1, td);
fdrop(fp2, td);
goto done2;
free4:
fdclose(fdp, fp2, sv[1], td);
fdrop(fp2, td);
free3:
fdclose(fdp, fp1, sv[0], td);
fdrop(fp1, td);
free2:
(void)soclose(so2);
free1:
(void)soclose(so1);
done2:
NET_UNLOCK_GIANT();
return (error);
}
static int
sendit(td, s, mp, flags)
register struct thread *td;
int s;
register struct msghdr *mp;
int flags;
{
struct mbuf *control;
struct sockaddr *to;
int error;
if (mp->msg_name != NULL) {
error = getsockaddr(&to, mp->msg_name, mp->msg_namelen);
if (error) {
to = NULL;
goto bad;
}
mp->msg_name = to;
} else {
to = NULL;
}
if (mp->msg_control) {
if (mp->msg_controllen < sizeof(struct cmsghdr)
#ifdef COMPAT_OLDSOCK
&& mp->msg_flags != MSG_COMPAT
#endif
) {
error = EINVAL;
goto bad;
}
error = sockargs(&control, mp->msg_control,
mp->msg_controllen, MT_CONTROL);
if (error)
goto bad;
#ifdef COMPAT_OLDSOCK
if (mp->msg_flags == MSG_COMPAT) {
register struct cmsghdr *cm;
M_PREPEND(control, sizeof(*cm), M_TRYWAIT);
if (control == 0) {
error = ENOBUFS;
goto bad;
} else {
cm = mtod(control, struct cmsghdr *);
cm->cmsg_len = control->m_len;
cm->cmsg_level = SOL_SOCKET;
cm->cmsg_type = SCM_RIGHTS;
}
}
#endif
} else {
control = NULL;
}
error = kern_sendit(td, s, mp, flags, control);
bad:
if (to)
FREE(to, M_SONAME);
return (error);
}
int
kern_sendit(td, s, mp, flags, control)
struct thread *td;
int s;
struct msghdr *mp;
int flags;
struct mbuf *control;
{
struct file *fp;
struct uio auio;
struct iovec *iov;
struct socket *so;
int i;
int len, error;
#ifdef KTRACE
struct uio *ktruio = NULL;
#endif
NET_LOCK_GIANT();
error = getsock(td->td_proc->p_fd, s, &fp);
if (error)
goto bad2;
so = (struct socket *)fp->f_data;
#ifdef MAC
SOCK_LOCK(so);
error = mac_check_socket_send(td->td_ucred, so);
SOCK_UNLOCK(so);
if (error)
goto bad;
#endif
auio.uio_iov = mp->msg_iov;
auio.uio_iovcnt = mp->msg_iovlen;
auio.uio_segflg = UIO_USERSPACE;
auio.uio_rw = UIO_WRITE;
auio.uio_td = td;
auio.uio_offset = 0; /* XXX */
auio.uio_resid = 0;
iov = mp->msg_iov;
for (i = 0; i < mp->msg_iovlen; i++, iov++) {
if ((auio.uio_resid += iov->iov_len) < 0) {
error = EINVAL;
goto bad;
}
}
#ifdef KTRACE
if (KTRPOINT(td, KTR_GENIO))
ktruio = cloneuio(&auio);
#endif
len = auio.uio_resid;
error = so->so_proto->pr_usrreqs->pru_sosend(so, mp->msg_name, &auio,
0, control, flags, td);
if (error) {
if (auio.uio_resid != len && (error == ERESTART ||
error == EINTR || error == EWOULDBLOCK))
error = 0;
/* Generation of SIGPIPE can be controlled per socket */
if (error == EPIPE && !(so->so_options & SO_NOSIGPIPE)) {
PROC_LOCK(td->td_proc);
psignal(td->td_proc, SIGPIPE);
PROC_UNLOCK(td->td_proc);
}
}
if (error == 0)
td->td_retval[0] = len - auio.uio_resid;
#ifdef KTRACE
if (ktruio != NULL) {
ktruio->uio_resid = td->td_retval[0];
ktrgenio(s, UIO_WRITE, ktruio, error);
}
#endif
bad:
fdrop(fp, td);
bad2:
NET_UNLOCK_GIANT();
return (error);
}
/*
* MPSAFE
*/
int
sendto(td, uap)
struct thread *td;
register struct sendto_args /* {
int s;
caddr_t buf;
size_t len;
int flags;
caddr_t to;
int tolen;
} */ *uap;
{
struct msghdr msg;
struct iovec aiov;
int error;
msg.msg_name = uap->to;
msg.msg_namelen = uap->tolen;
msg.msg_iov = &aiov;
msg.msg_iovlen = 1;
msg.msg_control = 0;
#ifdef COMPAT_OLDSOCK
msg.msg_flags = 0;
#endif
aiov.iov_base = uap->buf;
aiov.iov_len = uap->len;
error = sendit(td, uap->s, &msg, uap->flags);
return (error);
}
#ifdef COMPAT_OLDSOCK
/*
* MPSAFE
*/
int
osend(td, uap)
struct thread *td;
register struct osend_args /* {
int s;
caddr_t buf;
int len;
int flags;
} */ *uap;
{
struct msghdr msg;
struct iovec aiov;
int error;
msg.msg_name = 0;
msg.msg_namelen = 0;
msg.msg_iov = &aiov;
msg.msg_iovlen = 1;
aiov.iov_base = uap->buf;
aiov.iov_len = uap->len;
msg.msg_control = 0;
msg.msg_flags = 0;
error = sendit(td, uap->s, &msg, uap->flags);
return (error);
}
/*
* MPSAFE
*/
int
osendmsg(td, uap)
struct thread *td;
struct osendmsg_args /* {
int s;
caddr_t msg;
int flags;
} */ *uap;
{
struct msghdr msg;
struct iovec *iov;
int error;
error = copyin(uap->msg, &msg, sizeof (struct omsghdr));
if (error)
return (error);
error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
if (error)
return (error);
msg.msg_iov = iov;
msg.msg_flags = MSG_COMPAT;
error = sendit(td, uap->s, &msg, uap->flags);
free(iov, M_IOV);
return (error);
}
#endif
/*
* MPSAFE
*/
int
sendmsg(td, uap)
struct thread *td;
struct sendmsg_args /* {
int s;
caddr_t msg;
int flags;
} */ *uap;
{
struct msghdr msg;
struct iovec *iov;
int error;
error = copyin(uap->msg, &msg, sizeof (msg));
if (error)
return (error);
error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
if (error)
return (error);
msg.msg_iov = iov;
#ifdef COMPAT_OLDSOCK
msg.msg_flags = 0;
#endif
error = sendit(td, uap->s, &msg, uap->flags);
free(iov, M_IOV);
return (error);
}
static int
recvit(td, s, mp, namelenp)
struct thread *td;
int s;
struct msghdr *mp;
void *namelenp;
{
struct uio auio;
struct iovec *iov;
int i;
socklen_t len;
int error;
struct mbuf *m, *control = 0;
caddr_t ctlbuf;
struct file *fp;
struct socket *so;
struct sockaddr *fromsa = 0;
#ifdef KTRACE
struct uio *ktruio = NULL;
#endif
NET_LOCK_GIANT();
error = getsock(td->td_proc->p_fd, s, &fp);
if (error) {
NET_UNLOCK_GIANT();
return (error);
}
so = fp->f_data;
#ifdef MAC
SOCK_LOCK(so);
error = mac_check_socket_receive(td->td_ucred, so);
SOCK_UNLOCK(so);
if (error) {
fdrop(fp, td);
NET_UNLOCK_GIANT();
return (error);
}
#endif
auio.uio_iov = mp->msg_iov;
auio.uio_iovcnt = mp->msg_iovlen;
auio.uio_segflg = UIO_USERSPACE;
auio.uio_rw = UIO_READ;
auio.uio_td = td;
auio.uio_offset = 0; /* XXX */
auio.uio_resid = 0;
iov = mp->msg_iov;
for (i = 0; i < mp->msg_iovlen; i++, iov++) {
if ((auio.uio_resid += iov->iov_len) < 0) {
fdrop(fp, td);
NET_UNLOCK_GIANT();
return (EINVAL);
}
}
#ifdef KTRACE
if (KTRPOINT(td, KTR_GENIO))
ktruio = cloneuio(&auio);
#endif
len = auio.uio_resid;
error = so->so_proto->pr_usrreqs->pru_soreceive(so, &fromsa, &auio,
(struct mbuf **)0, mp->msg_control ? &control : (struct mbuf **)0,
&mp->msg_flags);
if (error) {
if (auio.uio_resid != (int)len && (error == ERESTART ||
error == EINTR || error == EWOULDBLOCK))
error = 0;
}
#ifdef KTRACE
if (ktruio != NULL) {
ktruio->uio_resid = (int)len - auio.uio_resid;
ktrgenio(s, UIO_READ, ktruio, error);
}
#endif
if (error)
goto out;
td->td_retval[0] = (int)len - auio.uio_resid;
if (mp->msg_name) {
len = mp->msg_namelen;
if (len <= 0 || fromsa == 0)
len = 0;
else {
/* save sa_len before it is destroyed by MSG_COMPAT */
len = MIN(len, fromsa->sa_len);
#ifdef COMPAT_OLDSOCK
if (mp->msg_flags & MSG_COMPAT)
((struct osockaddr *)fromsa)->sa_family =
fromsa->sa_family;
#endif
error = copyout(fromsa, mp->msg_name, (unsigned)len);
if (error)
goto out;
}
mp->msg_namelen = len;
if (namelenp &&
(error = copyout(&len, namelenp, sizeof (socklen_t)))) {
#ifdef COMPAT_OLDSOCK
if (mp->msg_flags & MSG_COMPAT)
error = 0; /* old recvfrom didn't check */
else
#endif
goto out;
}
}
if (mp->msg_control) {
#ifdef COMPAT_OLDSOCK
/*
* We assume that old recvmsg calls won't receive access
* rights and other control info, esp. as control info
* is always optional and those options didn't exist in 4.3.
* If we receive rights, trim the cmsghdr; anything else
* is tossed.
*/
if (control && mp->msg_flags & MSG_COMPAT) {
if (mtod(control, struct cmsghdr *)->cmsg_level !=
SOL_SOCKET ||
mtod(control, struct cmsghdr *)->cmsg_type !=
SCM_RIGHTS) {
mp->msg_controllen = 0;
goto out;
}
control->m_len -= sizeof (struct cmsghdr);
control->m_data += sizeof (struct cmsghdr);
}
#endif
len = mp->msg_controllen;
m = control;
mp->msg_controllen = 0;
ctlbuf = mp->msg_control;
while (m && len > 0) {
unsigned int tocopy;
if (len >= m->m_len)
tocopy = m->m_len;
else {
mp->msg_flags |= MSG_CTRUNC;
tocopy = len;
}
if ((error = copyout(mtod(m, caddr_t),
ctlbuf, tocopy)) != 0)
goto out;
ctlbuf += tocopy;
len -= tocopy;
m = m->m_next;
}
mp->msg_controllen = ctlbuf - (caddr_t)mp->msg_control;
}
out:
fdrop(fp, td);
NET_UNLOCK_GIANT();
if (fromsa)
FREE(fromsa, M_SONAME);
if (control)
m_freem(control);
return (error);
}
/*
* MPSAFE
*/
int
recvfrom(td, uap)
struct thread *td;
register struct recvfrom_args /* {
int s;
caddr_t buf;
size_t len;
int flags;
struct sockaddr * __restrict from;
socklen_t * __restrict fromlenaddr;
} */ *uap;
{
struct msghdr msg;
struct iovec aiov;
int error;
if (uap->fromlenaddr) {
error = copyin(uap->fromlenaddr,
&msg.msg_namelen, sizeof (msg.msg_namelen));
if (error)
goto done2;
} else {
msg.msg_namelen = 0;
}
msg.msg_name = uap->from;
msg.msg_iov = &aiov;
msg.msg_iovlen = 1;
aiov.iov_base = uap->buf;
aiov.iov_len = uap->len;
msg.msg_control = 0;
msg.msg_flags = uap->flags;
error = recvit(td, uap->s, &msg, uap->fromlenaddr);
done2:
return(error);
}
#ifdef COMPAT_OLDSOCK
/*
* MPSAFE
*/
int
orecvfrom(td, uap)
struct thread *td;
struct recvfrom_args *uap;
{
uap->flags |= MSG_COMPAT;
return (recvfrom(td, uap));
}
#endif
#ifdef COMPAT_OLDSOCK
/*
* MPSAFE
*/
int
orecv(td, uap)
struct thread *td;
register struct orecv_args /* {
int s;
caddr_t buf;
int len;
int flags;
} */ *uap;
{
struct msghdr msg;
struct iovec aiov;
int error;
msg.msg_name = 0;
msg.msg_namelen = 0;
msg.msg_iov = &aiov;
msg.msg_iovlen = 1;
aiov.iov_base = uap->buf;
aiov.iov_len = uap->len;
msg.msg_control = 0;
msg.msg_flags = uap->flags;
error = recvit(td, uap->s, &msg, NULL);
return (error);
}
/*
* Old recvmsg. This code takes advantage of the fact that the old msghdr
* overlays the new one, missing only the flags, and with the (old) access
* rights where the control fields are now.
*
* MPSAFE
*/
int
orecvmsg(td, uap)
struct thread *td;
struct orecvmsg_args /* {
int s;
struct omsghdr *msg;
int flags;
} */ *uap;
{
struct msghdr msg;
struct iovec *iov;
int error;
error = copyin(uap->msg, &msg, sizeof (struct omsghdr));
if (error)
return (error);
error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
if (error)
return (error);
msg.msg_flags = uap->flags | MSG_COMPAT;
msg.msg_iov = iov;
error = recvit(td, uap->s, &msg, &uap->msg->msg_namelen);
if (msg.msg_controllen && error == 0)
error = copyout(&msg.msg_controllen,
&uap->msg->msg_accrightslen, sizeof (int));
free(iov, M_IOV);
return (error);
}
#endif
/*
* MPSAFE
*/
int
recvmsg(td, uap)
struct thread *td;
struct recvmsg_args /* {
int s;
struct msghdr *msg;
int flags;
} */ *uap;
{
struct msghdr msg;
struct iovec *uiov, *iov;
int error;
error = copyin(uap->msg, &msg, sizeof (msg));
if (error)
return (error);
error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
if (error)
return (error);
msg.msg_flags = uap->flags;
#ifdef COMPAT_OLDSOCK
msg.msg_flags &= ~MSG_COMPAT;
#endif
uiov = msg.msg_iov;
msg.msg_iov = iov;
error = recvit(td, uap->s, &msg, NULL);
if (error == 0) {
msg.msg_iov = uiov;
error = copyout(&msg, uap->msg, sizeof(msg));
}
free(iov, M_IOV);
return (error);
}
/*
* MPSAFE
*/
/* ARGSUSED */
int
shutdown(td, uap)
struct thread *td;
register struct shutdown_args /* {
int s;
int how;
} */ *uap;
{
struct socket *so;
struct file *fp;
int error;
NET_LOCK_GIANT();
error = getsock(td->td_proc->p_fd, uap->s, &fp);
if (error == 0) {
so = fp->f_data;
error = soshutdown(so, uap->how);
fdrop(fp, td);
}
NET_UNLOCK_GIANT();
return (error);
}
/*
* MPSAFE
*/
/* ARGSUSED */
int
setsockopt(td, uap)
struct thread *td;
register struct setsockopt_args /* {
int s;
int level;
int name;
caddr_t val;
int valsize;
} */ *uap;
{
return (kern_setsockopt(td, uap->s, uap->level, uap->name,
uap->val, UIO_USERSPACE, uap->valsize));
}
int
kern_setsockopt(td, s, level, name, val, valseg, valsize)
struct thread *td;
int s;
int level;
int name;
void *val;
enum uio_seg valseg;
socklen_t valsize;
{
int error;
struct socket *so;
struct file *fp;
struct sockopt sopt;
if (val == NULL && valsize != 0)
return (EFAULT);
if (valsize < 0)
return (EINVAL);
sopt.sopt_dir = SOPT_SET;
sopt.sopt_level = level;
sopt.sopt_name = name;
sopt.sopt_val = val;
sopt.sopt_valsize = valsize;
switch (valseg) {
case UIO_USERSPACE:
sopt.sopt_td = td;
break;
case UIO_SYSSPACE:
sopt.sopt_td = NULL;
break;
default:
panic("kern_setsockopt called with bad valseg");
}
NET_LOCK_GIANT();
error = getsock(td->td_proc->p_fd, s, &fp);
if (error == 0) {
so = fp->f_data;
error = sosetopt(so, &sopt);
fdrop(fp, td);
}
NET_UNLOCK_GIANT();
return(error);
}
/*
* MPSAFE
*/
/* ARGSUSED */
int
getsockopt(td, uap)
struct thread *td;
register struct getsockopt_args /* {
int s;
int level;
int name;
void * __restrict val;
socklen_t * __restrict avalsize;
} */ *uap;
{
socklen_t valsize;
int error;
if (uap->val) {
error = copyin(uap->avalsize, &valsize, sizeof (valsize));
if (error)
return (error);
}
error = kern_getsockopt(td, uap->s, uap->level, uap->name,
uap->val, UIO_USERSPACE, &valsize);
if (error == 0)
error = copyout(&valsize, uap->avalsize, sizeof (valsize));
return (error);
}
/*
* Kernel version of getsockopt.
* optval can be a userland or userspace. optlen is always a kernel pointer.
*/
int
kern_getsockopt(td, s, level, name, val, valseg, valsize)
struct thread *td;
int s;
int level;
int name;
void *val;
enum uio_seg valseg;
socklen_t *valsize;
{
int error;
struct socket *so;
struct file *fp;
struct sockopt sopt;
if (val == NULL)
*valsize = 0;
if (*valsize < 0)
return (EINVAL);
sopt.sopt_dir = SOPT_GET;
sopt.sopt_level = level;
sopt.sopt_name = name;
sopt.sopt_val = val;
sopt.sopt_valsize = (size_t)*valsize; /* checked non-negative above */
switch (valseg) {
case UIO_USERSPACE:
sopt.sopt_td = td;
break;
case UIO_SYSSPACE:
sopt.sopt_td = NULL;
break;
default:
panic("kern_getsockopt called with bad valseg");
}
NET_LOCK_GIANT();
error = getsock(td->td_proc->p_fd, s, &fp);
if (error == 0) {
so = fp->f_data;
error = sogetopt(so, &sopt);
*valsize = sopt.sopt_valsize;
fdrop(fp, td);
}
NET_UNLOCK_GIANT();
return (error);
}
/*
* getsockname1() - Get socket name.
*
* MPSAFE
*/
/* ARGSUSED */
static int
getsockname1(td, uap, compat)
struct thread *td;
register struct getsockname_args /* {
int fdes;
struct sockaddr * __restrict asa;
socklen_t * __restrict alen;
} */ *uap;
int compat;
{
struct socket *so;
struct sockaddr *sa;
struct file *fp;
socklen_t len;
int error;
NET_LOCK_GIANT();
error = getsock(td->td_proc->p_fd, uap->fdes, &fp);
if (error)
goto done2;
so = fp->f_data;
error = copyin(uap->alen, &len, sizeof (len));
if (error)
goto done1;
if (len < 0) {
error = EINVAL;
goto done1;
}
sa = 0;
error = (*so->so_proto->pr_usrreqs->pru_sockaddr)(so, &sa);
if (error)
goto bad;
if (sa == 0) {
len = 0;
goto gotnothing;
}
len = MIN(len, sa->sa_len);
#ifdef COMPAT_OLDSOCK
if (compat)
((struct osockaddr *)sa)->sa_family = sa->sa_family;
#endif
error = copyout(sa, uap->asa, (u_int)len);
if (error == 0)
gotnothing:
error = copyout(&len, uap->alen, sizeof (len));
bad:
if (sa)
FREE(sa, M_SONAME);
done1:
fdrop(fp, td);
done2:
NET_UNLOCK_GIANT();
return (error);
}
/*
* MPSAFE
*/
int
getsockname(td, uap)
struct thread *td;
struct getsockname_args *uap;
{
return (getsockname1(td, uap, 0));
}
#ifdef COMPAT_OLDSOCK
/*
* MPSAFE
*/
int
ogetsockname(td, uap)
struct thread *td;
struct getsockname_args *uap;
{
return (getsockname1(td, uap, 1));
}
#endif /* COMPAT_OLDSOCK */
/*
* getpeername1() - Get name of peer for connected socket.
*
* MPSAFE
*/
/* ARGSUSED */
static int
getpeername1(td, uap, compat)
struct thread *td;
register struct getpeername_args /* {
int fdes;
struct sockaddr * __restrict asa;
socklen_t * __restrict alen;
} */ *uap;
int compat;
{
struct socket *so;
struct sockaddr *sa;
struct file *fp;
socklen_t len;
int error;
NET_LOCK_GIANT();
error = getsock(td->td_proc->p_fd, uap->fdes, &fp);
if (error)
goto done2;
so = fp->f_data;
if ((so->so_state & (SS_ISCONNECTED|SS_ISCONFIRMING)) == 0) {
error = ENOTCONN;
goto done1;
}
error = copyin(uap->alen, &len, sizeof (len));
if (error)
goto done1;
if (len < 0) {
error = EINVAL;
goto done1;
}
sa = 0;
error = (*so->so_proto->pr_usrreqs->pru_peeraddr)(so, &sa);
if (error)
goto bad;
if (sa == 0) {
len = 0;
goto gotnothing;
}
len = MIN(len, sa->sa_len);
#ifdef COMPAT_OLDSOCK
if (compat)
((struct osockaddr *)sa)->sa_family =
sa->sa_family;
#endif
error = copyout(sa, uap->asa, (u_int)len);
if (error)
goto bad;
gotnothing:
error = copyout(&len, uap->alen, sizeof (len));
bad:
if (sa)
FREE(sa, M_SONAME);
done1:
fdrop(fp, td);
done2:
NET_UNLOCK_GIANT();
return (error);
}
/*
* MPSAFE
*/
int
getpeername(td, uap)
struct thread *td;
struct getpeername_args *uap;
{
return (getpeername1(td, uap, 0));
}
#ifdef COMPAT_OLDSOCK
/*
* MPSAFE
*/
int
ogetpeername(td, uap)
struct thread *td;
struct ogetpeername_args *uap;
{
/* XXX uap should have type `getpeername_args *' to begin with. */
return (getpeername1(td, (struct getpeername_args *)uap, 1));
}
#endif /* COMPAT_OLDSOCK */
int
sockargs(mp, buf, buflen, type)
struct mbuf **mp;
caddr_t buf;
int buflen, type;
{
register struct sockaddr *sa;
register struct mbuf *m;
int error;
if ((u_int)buflen > MLEN) {
#ifdef COMPAT_OLDSOCK
if (type == MT_SONAME && (u_int)buflen <= 112)
buflen = MLEN; /* unix domain compat. hack */
else
#endif
if ((u_int)buflen > MCLBYTES)
return (EINVAL);
}
m = m_get(M_TRYWAIT, type);
if (m == NULL)
return (ENOBUFS);
if ((u_int)buflen > MLEN) {
MCLGET(m, M_TRYWAIT);
if ((m->m_flags & M_EXT) == 0) {
m_free(m);
return (ENOBUFS);
}
}
m->m_len = buflen;
error = copyin(buf, mtod(m, caddr_t), (u_int)buflen);
if (error)
(void) m_free(m);
else {
*mp = m;
if (type == MT_SONAME) {
sa = mtod(m, struct sockaddr *);
#if defined(COMPAT_OLDSOCK) && BYTE_ORDER != BIG_ENDIAN
if (sa->sa_family == 0 && sa->sa_len < AF_MAX)
sa->sa_family = sa->sa_len;
#endif
sa->sa_len = buflen;
}
}
return (error);
}
int
getsockaddr(namp, uaddr, len)
struct sockaddr **namp;
caddr_t uaddr;
size_t len;
{
struct sockaddr *sa;
int error;
if (len > SOCK_MAXADDRLEN)
return (ENAMETOOLONG);
if (len < offsetof(struct sockaddr, sa_data[0]))
return (EINVAL);
MALLOC(sa, struct sockaddr *, len, M_SONAME, M_WAITOK);
error = copyin(uaddr, sa, len);
if (error) {
FREE(sa, M_SONAME);
} else {
#if defined(COMPAT_OLDSOCK) && BYTE_ORDER != BIG_ENDIAN
if (sa->sa_family == 0 && sa->sa_len < AF_MAX)
sa->sa_family = sa->sa_len;
#endif
sa->sa_len = len;
*namp = sa;
}
return (error);
}
/*
* Detach mapped page and release resources back to the system.
*/
void
sf_buf_mext(void *addr, void *args)
{
vm_page_t m;
m = sf_buf_page(args);
sf_buf_free(args);
vm_page_lock_queues();
vm_page_unwire(m, 0);
/*
* Check for the object going away on us. This can
* happen since we don't hold a reference to it.
* If so, we're responsible for freeing the page.
*/
if (m->wire_count == 0 && m->object == NULL)
vm_page_free(m);
vm_page_unlock_queues();
}
/*
* sendfile(2)
*
* MPSAFE
*
* int sendfile(int fd, int s, off_t offset, size_t nbytes,
* struct sf_hdtr *hdtr, off_t *sbytes, int flags)
*
* Send a file specified by 'fd' and starting at 'offset' to a socket
* specified by 's'. Send only 'nbytes' of the file or until EOF if
* nbytes == 0. Optionally add a header and/or trailer to the socket
* output. If specified, write the total number of bytes sent into *sbytes.
*
*/
int
sendfile(struct thread *td, struct sendfile_args *uap)
{
return (do_sendfile(td, uap, 0));
}
#ifdef COMPAT_FREEBSD4
int
freebsd4_sendfile(struct thread *td, struct freebsd4_sendfile_args *uap)
{
struct sendfile_args args;
args.fd = uap->fd;
args.s = uap->s;
args.offset = uap->offset;
args.nbytes = uap->nbytes;
args.hdtr = uap->hdtr;
args.sbytes = uap->sbytes;
args.flags = uap->flags;
return (do_sendfile(td, &args, 1));
}
#endif /* COMPAT_FREEBSD4 */
static int
do_sendfile(struct thread *td, struct sendfile_args *uap, int compat)
{
struct vnode *vp;
struct vm_object *obj;
struct socket *so = NULL;
struct mbuf *m, *m_header = NULL;
struct sf_buf *sf;
struct vm_page *pg;
struct writev_args nuap;
struct sf_hdtr hdtr;
struct uio *hdr_uio = NULL;
off_t off, xfsize, hdtr_size, sbytes = 0;
int error, headersize = 0, headersent = 0;
mtx_lock(&Giant);
hdtr_size = 0;
/*
* The descriptor must be a regular file and have a backing VM object.
*/
if ((error = fgetvp_read(td, uap->fd, &vp)) != 0)
goto done;
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
if (vp->v_type != VREG || VOP_GETVOBJECT(vp, &obj) != 0) {
error = EINVAL;
VOP_UNLOCK(vp, 0, td);
goto done;
}
VOP_UNLOCK(vp, 0, td);
if ((error = fgetsock(td, uap->s, &so, NULL)) != 0)
goto done;
if (so->so_type != SOCK_STREAM) {
error = EINVAL;
goto done;
}
if ((so->so_state & SS_ISCONNECTED) == 0) {
error = ENOTCONN;
goto done;
}
if (uap->offset < 0) {
error = EINVAL;
goto done;
}
#ifdef MAC
SOCK_LOCK(so);
error = mac_check_socket_send(td->td_ucred, so);
SOCK_UNLOCK(so);
if (error)
goto done;
#endif
/*
* If specified, get the pointer to the sf_hdtr struct for
* any headers/trailers.
*/
if (uap->hdtr != NULL) {
error = copyin(uap->hdtr, &hdtr, sizeof(hdtr));
if (error)
goto done;
/*
* Send any headers.
*/
if (hdtr.headers != NULL) {
error = copyinuio(hdtr.headers, hdtr.hdr_cnt, &hdr_uio);
if (error)
goto done;
hdr_uio->uio_td = td;
hdr_uio->uio_rw = UIO_WRITE;
if (hdr_uio->uio_resid > 0) {
m_header = m_uiotombuf(hdr_uio, M_DONTWAIT, 0);
if (m_header == NULL)
goto done;
headersize = m_header->m_pkthdr.len;
if (compat)
sbytes += headersize;
}
}
}
/*
* Protect against multiple writers to the socket.
*/
SOCKBUF_LOCK(&so->so_snd);
(void) sblock(&so->so_snd, M_WAITOK);
SOCKBUF_UNLOCK(&so->so_snd);
/*
* Loop through the pages in the file, starting with the requested
* offset. Get a file page (do I/O if necessary), map the file page
* into an sf_buf, attach an mbuf header to the sf_buf, and queue
* it on the socket.
*/
for (off = uap->offset; ; off += xfsize, sbytes += xfsize) {
vm_pindex_t pindex;
vm_offset_t pgoff;
pindex = OFF_TO_IDX(off);
VM_OBJECT_LOCK(obj);
retry_lookup:
/*
* Calculate the amount to transfer. Not to exceed a page,
* the EOF, or the passed in nbytes.
*/
xfsize = obj->un_pager.vnp.vnp_size - off;
VM_OBJECT_UNLOCK(obj);
if (xfsize > PAGE_SIZE)
xfsize = PAGE_SIZE;
pgoff = (vm_offset_t)(off & PAGE_MASK);
if (PAGE_SIZE - pgoff < xfsize)
xfsize = PAGE_SIZE - pgoff;
if (uap->nbytes && xfsize > (uap->nbytes - sbytes))
xfsize = uap->nbytes - sbytes;
if (xfsize <= 0) {
if (m_header != NULL) {
m = m_header;
m_header = NULL;
SOCKBUF_LOCK(&so->so_snd);
goto retry_space;
} else
break;
}
/*
* Optimize the non-blocking case by looking at the socket space
* before going to the extra work of constituting the sf_buf.
*/
SOCKBUF_LOCK(&so->so_snd);
if ((so->so_state & SS_NBIO) && sbspace(&so->so_snd) <= 0) {
if (so->so_snd.sb_state & SBS_CANTSENDMORE)
error = EPIPE;
else
error = EAGAIN;
sbunlock(&so->so_snd);
SOCKBUF_UNLOCK(&so->so_snd);
goto done;
}
SOCKBUF_UNLOCK(&so->so_snd);
VM_OBJECT_LOCK(obj);
/*
* Attempt to look up the page.
*
* Allocate if not found
*
* Wait and loop if busy.
*/
pg = vm_page_lookup(obj, pindex);
if (pg == NULL) {
pg = vm_page_alloc(obj, pindex, VM_ALLOC_NOBUSY |
VM_ALLOC_NORMAL | VM_ALLOC_WIRED);
if (pg == NULL) {
VM_OBJECT_UNLOCK(obj);
VM_WAIT;
VM_OBJECT_LOCK(obj);
goto retry_lookup;
}
vm_page_lock_queues();
} else {
vm_page_lock_queues();
if (vm_page_sleep_if_busy(pg, TRUE, "sfpbsy"))
goto retry_lookup;
/*
* Wire the page so it does not get ripped out from
* under us.
*/
vm_page_wire(pg);
}
/*
* If page is not valid for what we need, initiate I/O
*/
if (pg->valid && vm_page_is_valid(pg, pgoff, xfsize)) {
VM_OBJECT_UNLOCK(obj);
} else if (uap->flags & SF_NODISKIO) {
error = EBUSY;
} else {
int bsize, resid;
/*
* Ensure that our page is still around when the I/O
* completes.
*/
vm_page_io_start(pg);
vm_page_unlock_queues();
VM_OBJECT_UNLOCK(obj);
/*
* Get the page from backing store.
*/
bsize = vp->v_mount->mnt_stat.f_iosize;
vn_lock(vp, LK_SHARED | LK_NOPAUSE | LK_RETRY, td);
/*
* XXXMAC: Because we don't have fp->f_cred here,
* we pass in NOCRED. This is probably wrong, but
* is consistent with our original implementation.
*/
error = vn_rdwr(UIO_READ, vp, NULL, MAXBSIZE,
trunc_page(off), UIO_NOCOPY, IO_NODELOCKED |
IO_VMIO | ((MAXBSIZE / bsize) << IO_SEQSHIFT),
td->td_ucred, NOCRED, &resid, td);
VOP_UNLOCK(vp, 0, td);
VM_OBJECT_LOCK(obj);
vm_page_lock_queues();
vm_page_io_finish(pg);
if (!error)
VM_OBJECT_UNLOCK(obj);
mbstat.sf_iocnt++;
}
if (error) {
vm_page_unwire(pg, 0);
/*
* See if anyone else might know about this page.
* If not and it is not valid, then free it.
*/
if (pg->wire_count == 0 && pg->valid == 0 &&
pg->busy == 0 && !(pg->flags & PG_BUSY) &&
pg->hold_count == 0) {
vm_page_free(pg);
}
vm_page_unlock_queues();
VM_OBJECT_UNLOCK(obj);
SOCKBUF_LOCK(&so->so_snd);
sbunlock(&so->so_snd);
SOCKBUF_UNLOCK(&so->so_snd);
goto done;
}
vm_page_unlock_queues();
/*
* Get a sendfile buf. We usually wait as long as necessary,
* but this wait can be interrupted.
*/
if ((sf = sf_buf_alloc(pg, SFB_CATCH)) == NULL) {
mbstat.sf_allocfail++;
vm_page_lock_queues();
vm_page_unwire(pg, 0);
if (pg->wire_count == 0 && pg->object == NULL)
vm_page_free(pg);
vm_page_unlock_queues();
SOCKBUF_LOCK(&so->so_snd);
sbunlock(&so->so_snd);
SOCKBUF_UNLOCK(&so->so_snd);
error = EINTR;
goto done;
}
/*
* Get an mbuf header and set it up as having external storage.
*/
if (m_header)
MGET(m, M_TRYWAIT, MT_DATA);
else
MGETHDR(m, M_TRYWAIT, MT_DATA);
if (m == NULL) {
error = ENOBUFS;
sf_buf_mext((void *)sf_buf_kva(sf), sf);
SOCKBUF_LOCK(&so->so_snd);
sbunlock(&so->so_snd);
SOCKBUF_UNLOCK(&so->so_snd);
goto done;
}
/*
* Setup external storage for mbuf.
*/
MEXTADD(m, sf_buf_kva(sf), PAGE_SIZE, sf_buf_mext, sf, M_RDONLY,
EXT_SFBUF);
m->m_data = (char *)sf_buf_kva(sf) + pgoff;
m->m_pkthdr.len = m->m_len = xfsize;
if (m_header) {
m_cat(m_header, m);
m = m_header;
m_header = NULL;
m_fixhdr(m);
}
/*
* Add the buffer to the socket buffer chain.
*/
SOCKBUF_LOCK(&so->so_snd);
retry_space:
/*
* Make sure that the socket is still able to take more data.
* CANTSENDMORE being true usually means that the connection
* was closed. so_error is true when an error was sensed after
* a previous send.
* The state is checked after the page mapping and buffer
* allocation above since those operations may block and make
* any socket checks stale. From this point forward, nothing
* blocks before the pru_send (or more accurately, any blocking
* results in a loop back to here to re-check).
*/
SOCKBUF_LOCK_ASSERT(&so->so_snd);
if ((so->so_snd.sb_state & SBS_CANTSENDMORE) || so->so_error) {
if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
error = EPIPE;
} else {
error = so->so_error;
so->so_error = 0;
}
m_freem(m);
sbunlock(&so->so_snd);
SOCKBUF_UNLOCK(&so->so_snd);
goto done;
}
/*
* Wait for socket space to become available. We do this just
* after checking the connection state above in order to avoid
* a race condition with sbwait().
*/
if (sbspace(&so->so_snd) < so->so_snd.sb_lowat) {
if (so->so_state & SS_NBIO) {
m_freem(m);
sbunlock(&so->so_snd);
SOCKBUF_UNLOCK(&so->so_snd);
error = EAGAIN;
goto done;
}
error = sbwait(&so->so_snd);
/*
* An error from sbwait usually indicates that we've
* been interrupted by a signal. If we've sent anything
* then return bytes sent, otherwise return the error.
*/
if (error) {
m_freem(m);
sbunlock(&so->so_snd);
SOCKBUF_UNLOCK(&so->so_snd);
goto done;
}
goto retry_space;
}
SOCKBUF_UNLOCK(&so->so_snd);
error = (*so->so_proto->pr_usrreqs->pru_send)(so, 0, m, 0, 0, td);
if (error) {
SOCKBUF_LOCK(&so->so_snd);
sbunlock(&so->so_snd);
SOCKBUF_UNLOCK(&so->so_snd);
goto done;
}
headersent = 1;
}
SOCKBUF_LOCK(&so->so_snd);
sbunlock(&so->so_snd);
SOCKBUF_UNLOCK(&so->so_snd);
/*
* Send trailers. Wimp out and use writev(2).
*/
if (uap->hdtr != NULL && hdtr.trailers != NULL) {
nuap.fd = uap->s;
nuap.iovp = hdtr.trailers;
nuap.iovcnt = hdtr.trl_cnt;
error = writev(td, &nuap);
if (error)
goto done;
if (compat)
sbytes += td->td_retval[0];
else
hdtr_size += td->td_retval[0];
}
done:
if (headersent) {
if (!compat)
hdtr_size += headersize;
} else {
if (compat)
sbytes -= headersize;
}
/*
* If there was no error we have to clear td->td_retval[0]
* because it may have been set by writev.
*/
if (error == 0) {
td->td_retval[0] = 0;
}
if (uap->sbytes != NULL) {
if (!compat)
sbytes += hdtr_size;
copyout(&sbytes, uap->sbytes, sizeof(off_t));
}
if (vp)
vrele(vp);
if (so)
fputsock(so);
if (hdr_uio != NULL)
free(hdr_uio, M_IOV);
if (m_header)
m_freem(m_header);
mtx_unlock(&Giant);
if (error == ERESTART)
error = EINTR;
return (error);
}