freebsd-dev/sys/kern/sys_socket.c
John Baldwin 12fb14f36d Don't grab SOCK_LOCK for soref() when queuing an AIO request.
The AIO job holds a reference on the associated file descriptor, so the
socket's count should already be > 0.  This fixes a LOR with the socket
buffer lock after recent socket locking changes in HEAD.

Sponsored by:	Chelsio Communications
2017-08-25 23:10:27 +00:00

820 lines
20 KiB
C

/*-
* Copyright (c) 1982, 1986, 1990, 1993
* The Regents of the University of California. 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.
* 3. 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.
*
* @(#)sys_socket.c 8.1 (Berkeley) 6/10/93
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/aio.h>
#include <sys/domain.h>
#include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/sigio.h>
#include <sys/signal.h>
#include <sys/signalvar.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/filio.h> /* XXX */
#include <sys/sockio.h>
#include <sys/stat.h>
#include <sys/sysctl.h>
#include <sys/sysproto.h>
#include <sys/taskqueue.h>
#include <sys/uio.h>
#include <sys/ucred.h>
#include <sys/un.h>
#include <sys/unpcb.h>
#include <sys/user.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/route.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/in_pcb.h>
#include <security/mac/mac_framework.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_extern.h>
#include <vm/vm_map.h>
static SYSCTL_NODE(_kern_ipc, OID_AUTO, aio, CTLFLAG_RD, NULL,
"socket AIO stats");
static int empty_results;
SYSCTL_INT(_kern_ipc_aio, OID_AUTO, empty_results, CTLFLAG_RD, &empty_results,
0, "socket operation returned EAGAIN");
static int empty_retries;
SYSCTL_INT(_kern_ipc_aio, OID_AUTO, empty_retries, CTLFLAG_RD, &empty_retries,
0, "socket operation retries");
static fo_rdwr_t soo_read;
static fo_rdwr_t soo_write;
static fo_ioctl_t soo_ioctl;
static fo_poll_t soo_poll;
extern fo_kqfilter_t soo_kqfilter;
static fo_stat_t soo_stat;
static fo_close_t soo_close;
static fo_fill_kinfo_t soo_fill_kinfo;
static fo_aio_queue_t soo_aio_queue;
static void soo_aio_cancel(struct kaiocb *job);
struct fileops socketops = {
.fo_read = soo_read,
.fo_write = soo_write,
.fo_truncate = invfo_truncate,
.fo_ioctl = soo_ioctl,
.fo_poll = soo_poll,
.fo_kqfilter = soo_kqfilter,
.fo_stat = soo_stat,
.fo_close = soo_close,
.fo_chmod = invfo_chmod,
.fo_chown = invfo_chown,
.fo_sendfile = invfo_sendfile,
.fo_fill_kinfo = soo_fill_kinfo,
.fo_aio_queue = soo_aio_queue,
.fo_flags = DFLAG_PASSABLE
};
static int
soo_read(struct file *fp, struct uio *uio, struct ucred *active_cred,
int flags, struct thread *td)
{
struct socket *so = fp->f_data;
int error;
#ifdef MAC
error = mac_socket_check_receive(active_cred, so);
if (error)
return (error);
#endif
error = soreceive(so, 0, uio, 0, 0, 0);
return (error);
}
static int
soo_write(struct file *fp, struct uio *uio, struct ucred *active_cred,
int flags, struct thread *td)
{
struct socket *so = fp->f_data;
int error;
#ifdef MAC
error = mac_socket_check_send(active_cred, so);
if (error)
return (error);
#endif
error = sosend(so, 0, uio, 0, 0, 0, uio->uio_td);
if (error == EPIPE && (so->so_options & SO_NOSIGPIPE) == 0) {
PROC_LOCK(uio->uio_td->td_proc);
tdsignal(uio->uio_td, SIGPIPE);
PROC_UNLOCK(uio->uio_td->td_proc);
}
return (error);
}
static int
soo_ioctl(struct file *fp, u_long cmd, void *data, struct ucred *active_cred,
struct thread *td)
{
struct socket *so = fp->f_data;
int error = 0;
switch (cmd) {
case FIONBIO:
SOCK_LOCK(so);
if (*(int *)data)
so->so_state |= SS_NBIO;
else
so->so_state &= ~SS_NBIO;
SOCK_UNLOCK(so);
break;
case FIOASYNC:
if (*(int *)data) {
SOCK_LOCK(so);
so->so_state |= SS_ASYNC;
if (SOLISTENING(so)) {
so->sol_sbrcv_flags |= SB_ASYNC;
so->sol_sbsnd_flags |= SB_ASYNC;
} else {
SOCKBUF_LOCK(&so->so_rcv);
so->so_rcv.sb_flags |= SB_ASYNC;
SOCKBUF_UNLOCK(&so->so_rcv);
SOCKBUF_LOCK(&so->so_snd);
so->so_snd.sb_flags |= SB_ASYNC;
SOCKBUF_UNLOCK(&so->so_snd);
}
SOCK_UNLOCK(so);
} else {
SOCK_LOCK(so);
so->so_state &= ~SS_ASYNC;
if (SOLISTENING(so)) {
so->sol_sbrcv_flags &= ~SB_ASYNC;
so->sol_sbsnd_flags &= ~SB_ASYNC;
} else {
SOCKBUF_LOCK(&so->so_rcv);
so->so_rcv.sb_flags &= ~SB_ASYNC;
SOCKBUF_UNLOCK(&so->so_rcv);
SOCKBUF_LOCK(&so->so_snd);
so->so_snd.sb_flags &= ~SB_ASYNC;
SOCKBUF_UNLOCK(&so->so_snd);
}
SOCK_UNLOCK(so);
}
break;
case FIONREAD:
/* Unlocked read. */
*(int *)data = sbavail(&so->so_rcv);
break;
case FIONWRITE:
/* Unlocked read. */
*(int *)data = sbavail(&so->so_snd);
break;
case FIONSPACE:
/* Unlocked read. */
if ((so->so_snd.sb_hiwat < sbused(&so->so_snd)) ||
(so->so_snd.sb_mbmax < so->so_snd.sb_mbcnt))
*(int *)data = 0;
else
*(int *)data = sbspace(&so->so_snd);
break;
case FIOSETOWN:
error = fsetown(*(int *)data, &so->so_sigio);
break;
case FIOGETOWN:
*(int *)data = fgetown(&so->so_sigio);
break;
case SIOCSPGRP:
error = fsetown(-(*(int *)data), &so->so_sigio);
break;
case SIOCGPGRP:
*(int *)data = -fgetown(&so->so_sigio);
break;
case SIOCATMARK:
/* Unlocked read. */
*(int *)data = (so->so_rcv.sb_state & SBS_RCVATMARK) != 0;
break;
default:
/*
* Interface/routing/protocol specific ioctls: interface and
* routing ioctls should have a different entry since a
* socket is unnecessary.
*/
if (IOCGROUP(cmd) == 'i')
error = ifioctl(so, cmd, data, td);
else if (IOCGROUP(cmd) == 'r') {
CURVNET_SET(so->so_vnet);
error = rtioctl_fib(cmd, data, so->so_fibnum);
CURVNET_RESTORE();
} else {
CURVNET_SET(so->so_vnet);
error = ((*so->so_proto->pr_usrreqs->pru_control)
(so, cmd, data, 0, td));
CURVNET_RESTORE();
}
break;
}
return (error);
}
static int
soo_poll(struct file *fp, int events, struct ucred *active_cred,
struct thread *td)
{
struct socket *so = fp->f_data;
#ifdef MAC
int error;
error = mac_socket_check_poll(active_cred, so);
if (error)
return (error);
#endif
return (sopoll(so, events, fp->f_cred, td));
}
static int
soo_stat(struct file *fp, struct stat *ub, struct ucred *active_cred,
struct thread *td)
{
struct socket *so = fp->f_data;
#ifdef MAC
int error;
#endif
bzero((caddr_t)ub, sizeof (*ub));
ub->st_mode = S_IFSOCK;
#ifdef MAC
error = mac_socket_check_stat(active_cred, so);
if (error)
return (error);
#endif
if (!SOLISTENING(so)) {
struct sockbuf *sb;
/*
* If SBS_CANTRCVMORE is set, but there's still data left
* in the receive buffer, the socket is still readable.
*/
sb = &so->so_rcv;
SOCKBUF_LOCK(sb);
if ((sb->sb_state & SBS_CANTRCVMORE) == 0 || sbavail(sb))
ub->st_mode |= S_IRUSR | S_IRGRP | S_IROTH;
ub->st_size = sbavail(sb) - sb->sb_ctl;
SOCKBUF_UNLOCK(sb);
sb = &so->so_snd;
SOCKBUF_LOCK(sb);
if ((sb->sb_state & SBS_CANTSENDMORE) == 0)
ub->st_mode |= S_IWUSR | S_IWGRP | S_IWOTH;
SOCKBUF_UNLOCK(sb);
}
ub->st_uid = so->so_cred->cr_uid;
ub->st_gid = so->so_cred->cr_gid;
return (*so->so_proto->pr_usrreqs->pru_sense)(so, ub);
}
/*
* API socket close on file pointer. We call soclose() to close the socket
* (including initiating closing protocols). soclose() will sorele() the
* file reference but the actual socket will not go away until the socket's
* ref count hits 0.
*/
static int
soo_close(struct file *fp, struct thread *td)
{
int error = 0;
struct socket *so;
so = fp->f_data;
fp->f_ops = &badfileops;
fp->f_data = NULL;
if (so)
error = soclose(so);
return (error);
}
static int
soo_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
{
struct sockaddr *sa;
struct inpcb *inpcb;
struct unpcb *unpcb;
struct socket *so;
int error;
kif->kf_type = KF_TYPE_SOCKET;
so = fp->f_data;
kif->kf_un.kf_sock.kf_sock_domain0 =
so->so_proto->pr_domain->dom_family;
kif->kf_un.kf_sock.kf_sock_type0 = so->so_type;
kif->kf_un.kf_sock.kf_sock_protocol0 = so->so_proto->pr_protocol;
kif->kf_un.kf_sock.kf_sock_pcb = (uintptr_t)so->so_pcb;
switch (kif->kf_un.kf_sock.kf_sock_domain0) {
case AF_INET:
case AF_INET6:
if (kif->kf_un.kf_sock.kf_sock_protocol0 == IPPROTO_TCP) {
if (so->so_pcb != NULL) {
inpcb = (struct inpcb *)(so->so_pcb);
kif->kf_un.kf_sock.kf_sock_inpcb =
(uintptr_t)inpcb->inp_ppcb;
kif->kf_un.kf_sock.kf_sock_sendq =
sbused(&so->so_snd);
kif->kf_un.kf_sock.kf_sock_recvq =
sbused(&so->so_rcv);
}
}
break;
case AF_UNIX:
if (so->so_pcb != NULL) {
unpcb = (struct unpcb *)(so->so_pcb);
if (unpcb->unp_conn) {
kif->kf_un.kf_sock.kf_sock_unpconn =
(uintptr_t)unpcb->unp_conn;
kif->kf_un.kf_sock.kf_sock_rcv_sb_state =
so->so_rcv.sb_state;
kif->kf_un.kf_sock.kf_sock_snd_sb_state =
so->so_snd.sb_state;
kif->kf_un.kf_sock.kf_sock_sendq =
sbused(&so->so_snd);
kif->kf_un.kf_sock.kf_sock_recvq =
sbused(&so->so_rcv);
}
}
break;
}
error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa);
if (error == 0 &&
sa->sa_len <= sizeof(kif->kf_un.kf_sock.kf_sa_local)) {
bcopy(sa, &kif->kf_un.kf_sock.kf_sa_local, sa->sa_len);
free(sa, M_SONAME);
}
error = so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa);
if (error == 0 &&
sa->sa_len <= sizeof(kif->kf_un.kf_sock.kf_sa_peer)) {
bcopy(sa, &kif->kf_un.kf_sock.kf_sa_peer, sa->sa_len);
free(sa, M_SONAME);
}
strncpy(kif->kf_path, so->so_proto->pr_domain->dom_name,
sizeof(kif->kf_path));
return (0);
}
/*
* Use the 'backend3' field in AIO jobs to store the amount of data
* completed by the AIO job so far.
*/
#define aio_done backend3
static STAILQ_HEAD(, task) soaio_jobs;
static struct mtx soaio_jobs_lock;
static struct task soaio_kproc_task;
static int soaio_starting, soaio_idle, soaio_queued;
static struct unrhdr *soaio_kproc_unr;
static int soaio_max_procs = MAX_AIO_PROCS;
SYSCTL_INT(_kern_ipc_aio, OID_AUTO, max_procs, CTLFLAG_RW, &soaio_max_procs, 0,
"Maximum number of kernel processes to use for async socket IO");
static int soaio_num_procs;
SYSCTL_INT(_kern_ipc_aio, OID_AUTO, num_procs, CTLFLAG_RD, &soaio_num_procs, 0,
"Number of active kernel processes for async socket IO");
static int soaio_target_procs = TARGET_AIO_PROCS;
SYSCTL_INT(_kern_ipc_aio, OID_AUTO, target_procs, CTLFLAG_RD,
&soaio_target_procs, 0,
"Preferred number of ready kernel processes for async socket IO");
static int soaio_lifetime;
SYSCTL_INT(_kern_ipc_aio, OID_AUTO, lifetime, CTLFLAG_RW, &soaio_lifetime, 0,
"Maximum lifetime for idle aiod");
static void
soaio_kproc_loop(void *arg)
{
struct proc *p;
struct vmspace *myvm;
struct task *task;
int error, id, pending;
id = (intptr_t)arg;
/*
* Grab an extra reference on the daemon's vmspace so that it
* doesn't get freed by jobs that switch to a different
* vmspace.
*/
p = curproc;
myvm = vmspace_acquire_ref(p);
mtx_lock(&soaio_jobs_lock);
MPASS(soaio_starting > 0);
soaio_starting--;
for (;;) {
while (!STAILQ_EMPTY(&soaio_jobs)) {
task = STAILQ_FIRST(&soaio_jobs);
STAILQ_REMOVE_HEAD(&soaio_jobs, ta_link);
soaio_queued--;
pending = task->ta_pending;
task->ta_pending = 0;
mtx_unlock(&soaio_jobs_lock);
task->ta_func(task->ta_context, pending);
mtx_lock(&soaio_jobs_lock);
}
MPASS(soaio_queued == 0);
if (p->p_vmspace != myvm) {
mtx_unlock(&soaio_jobs_lock);
vmspace_switch_aio(myvm);
mtx_lock(&soaio_jobs_lock);
continue;
}
soaio_idle++;
error = mtx_sleep(&soaio_idle, &soaio_jobs_lock, 0, "-",
soaio_lifetime);
soaio_idle--;
if (error == EWOULDBLOCK && STAILQ_EMPTY(&soaio_jobs) &&
soaio_num_procs > soaio_target_procs)
break;
}
soaio_num_procs--;
mtx_unlock(&soaio_jobs_lock);
free_unr(soaio_kproc_unr, id);
kproc_exit(0);
}
static void
soaio_kproc_create(void *context, int pending)
{
struct proc *p;
int error, id;
mtx_lock(&soaio_jobs_lock);
for (;;) {
if (soaio_num_procs < soaio_target_procs) {
/* Must create */
} else if (soaio_num_procs >= soaio_max_procs) {
/*
* Hit the limit on kernel processes, don't
* create another one.
*/
break;
} else if (soaio_queued <= soaio_idle + soaio_starting) {
/*
* No more AIO jobs waiting for a process to be
* created, so stop.
*/
break;
}
soaio_starting++;
mtx_unlock(&soaio_jobs_lock);
id = alloc_unr(soaio_kproc_unr);
error = kproc_create(soaio_kproc_loop, (void *)(intptr_t)id,
&p, 0, 0, "soaiod%d", id);
if (error != 0) {
free_unr(soaio_kproc_unr, id);
mtx_lock(&soaio_jobs_lock);
soaio_starting--;
break;
}
mtx_lock(&soaio_jobs_lock);
soaio_num_procs++;
}
mtx_unlock(&soaio_jobs_lock);
}
void
soaio_enqueue(struct task *task)
{
mtx_lock(&soaio_jobs_lock);
MPASS(task->ta_pending == 0);
task->ta_pending++;
STAILQ_INSERT_TAIL(&soaio_jobs, task, ta_link);
soaio_queued++;
if (soaio_queued <= soaio_idle)
wakeup_one(&soaio_idle);
else if (soaio_num_procs < soaio_max_procs)
taskqueue_enqueue(taskqueue_thread, &soaio_kproc_task);
mtx_unlock(&soaio_jobs_lock);
}
static void
soaio_init(void)
{
soaio_lifetime = AIOD_LIFETIME_DEFAULT;
STAILQ_INIT(&soaio_jobs);
mtx_init(&soaio_jobs_lock, "soaio jobs", NULL, MTX_DEF);
soaio_kproc_unr = new_unrhdr(1, INT_MAX, NULL);
TASK_INIT(&soaio_kproc_task, 0, soaio_kproc_create, NULL);
if (soaio_target_procs > 0)
taskqueue_enqueue(taskqueue_thread, &soaio_kproc_task);
}
SYSINIT(soaio, SI_SUB_VFS, SI_ORDER_ANY, soaio_init, NULL);
static __inline int
soaio_ready(struct socket *so, struct sockbuf *sb)
{
return (sb == &so->so_rcv ? soreadable(so) : sowriteable(so));
}
static void
soaio_process_job(struct socket *so, struct sockbuf *sb, struct kaiocb *job)
{
struct ucred *td_savedcred;
struct thread *td;
struct file *fp;
struct uio uio;
struct iovec iov;
size_t cnt, done;
long ru_before;
int error, flags;
SOCKBUF_UNLOCK(sb);
aio_switch_vmspace(job);
td = curthread;
fp = job->fd_file;
retry:
td_savedcred = td->td_ucred;
td->td_ucred = job->cred;
done = job->aio_done;
cnt = job->uaiocb.aio_nbytes - done;
iov.iov_base = (void *)((uintptr_t)job->uaiocb.aio_buf + done);
iov.iov_len = cnt;
uio.uio_iov = &iov;
uio.uio_iovcnt = 1;
uio.uio_offset = 0;
uio.uio_resid = cnt;
uio.uio_segflg = UIO_USERSPACE;
uio.uio_td = td;
flags = MSG_NBIO;
/*
* For resource usage accounting, only count a completed request
* as a single message to avoid counting multiple calls to
* sosend/soreceive on a blocking socket.
*/
if (sb == &so->so_rcv) {
uio.uio_rw = UIO_READ;
ru_before = td->td_ru.ru_msgrcv;
#ifdef MAC
error = mac_socket_check_receive(fp->f_cred, so);
if (error == 0)
#endif
error = soreceive(so, NULL, &uio, NULL, NULL, &flags);
if (td->td_ru.ru_msgrcv != ru_before)
job->msgrcv = 1;
} else {
if (!TAILQ_EMPTY(&sb->sb_aiojobq))
flags |= MSG_MORETOCOME;
uio.uio_rw = UIO_WRITE;
ru_before = td->td_ru.ru_msgsnd;
#ifdef MAC
error = mac_socket_check_send(fp->f_cred, so);
if (error == 0)
#endif
error = sosend(so, NULL, &uio, NULL, NULL, flags, td);
if (td->td_ru.ru_msgsnd != ru_before)
job->msgsnd = 1;
if (error == EPIPE && (so->so_options & SO_NOSIGPIPE) == 0) {
PROC_LOCK(job->userproc);
kern_psignal(job->userproc, SIGPIPE);
PROC_UNLOCK(job->userproc);
}
}
done += cnt - uio.uio_resid;
job->aio_done = done;
td->td_ucred = td_savedcred;
if (error == EWOULDBLOCK) {
/*
* The request was either partially completed or not
* completed at all due to racing with a read() or
* write() on the socket. If the socket is
* non-blocking, return with any partial completion.
* If the socket is blocking or if no progress has
* been made, requeue this request at the head of the
* queue to try again when the socket is ready.
*/
MPASS(done != job->uaiocb.aio_nbytes);
SOCKBUF_LOCK(sb);
if (done == 0 || !(so->so_state & SS_NBIO)) {
empty_results++;
if (soaio_ready(so, sb)) {
empty_retries++;
SOCKBUF_UNLOCK(sb);
goto retry;
}
if (!aio_set_cancel_function(job, soo_aio_cancel)) {
SOCKBUF_UNLOCK(sb);
if (done != 0)
aio_complete(job, done, 0);
else
aio_cancel(job);
SOCKBUF_LOCK(sb);
} else {
TAILQ_INSERT_HEAD(&sb->sb_aiojobq, job, list);
}
return;
}
SOCKBUF_UNLOCK(sb);
}
if (done != 0 && (error == ERESTART || error == EINTR ||
error == EWOULDBLOCK))
error = 0;
if (error)
aio_complete(job, -1, error);
else
aio_complete(job, done, 0);
SOCKBUF_LOCK(sb);
}
static void
soaio_process_sb(struct socket *so, struct sockbuf *sb)
{
struct kaiocb *job;
CURVNET_SET(so->so_vnet);
SOCKBUF_LOCK(sb);
while (!TAILQ_EMPTY(&sb->sb_aiojobq) && soaio_ready(so, sb)) {
job = TAILQ_FIRST(&sb->sb_aiojobq);
TAILQ_REMOVE(&sb->sb_aiojobq, job, list);
if (!aio_clear_cancel_function(job))
continue;
soaio_process_job(so, sb, job);
}
/*
* If there are still pending requests, the socket must not be
* ready so set SB_AIO to request a wakeup when the socket
* becomes ready.
*/
if (!TAILQ_EMPTY(&sb->sb_aiojobq))
sb->sb_flags |= SB_AIO;
sb->sb_flags &= ~SB_AIO_RUNNING;
SOCKBUF_UNLOCK(sb);
SOCK_LOCK(so);
sorele(so);
CURVNET_RESTORE();
}
void
soaio_rcv(void *context, int pending)
{
struct socket *so;
so = context;
soaio_process_sb(so, &so->so_rcv);
}
void
soaio_snd(void *context, int pending)
{
struct socket *so;
so = context;
soaio_process_sb(so, &so->so_snd);
}
void
sowakeup_aio(struct socket *so, struct sockbuf *sb)
{
SOCKBUF_LOCK_ASSERT(sb);
sb->sb_flags &= ~SB_AIO;
if (sb->sb_flags & SB_AIO_RUNNING)
return;
sb->sb_flags |= SB_AIO_RUNNING;
soref(so);
soaio_enqueue(&sb->sb_aiotask);
}
static void
soo_aio_cancel(struct kaiocb *job)
{
struct socket *so;
struct sockbuf *sb;
long done;
int opcode;
so = job->fd_file->f_data;
opcode = job->uaiocb.aio_lio_opcode;
if (opcode == LIO_READ)
sb = &so->so_rcv;
else {
MPASS(opcode == LIO_WRITE);
sb = &so->so_snd;
}
SOCKBUF_LOCK(sb);
if (!aio_cancel_cleared(job))
TAILQ_REMOVE(&sb->sb_aiojobq, job, list);
if (TAILQ_EMPTY(&sb->sb_aiojobq))
sb->sb_flags &= ~SB_AIO;
SOCKBUF_UNLOCK(sb);
done = job->aio_done;
if (done != 0)
aio_complete(job, done, 0);
else
aio_cancel(job);
}
static int
soo_aio_queue(struct file *fp, struct kaiocb *job)
{
struct socket *so;
struct sockbuf *sb;
int error;
so = fp->f_data;
error = (*so->so_proto->pr_usrreqs->pru_aio_queue)(so, job);
if (error == 0)
return (0);
switch (job->uaiocb.aio_lio_opcode) {
case LIO_READ:
sb = &so->so_rcv;
break;
case LIO_WRITE:
sb = &so->so_snd;
break;
default:
return (EINVAL);
}
SOCKBUF_LOCK(sb);
if (!aio_set_cancel_function(job, soo_aio_cancel))
panic("new job was cancelled");
TAILQ_INSERT_TAIL(&sb->sb_aiojobq, job, list);
if (!(sb->sb_flags & SB_AIO_RUNNING)) {
if (soaio_ready(so, sb))
sowakeup_aio(so, sb);
else
sb->sb_flags |= SB_AIO;
}
SOCKBUF_UNLOCK(sb);
return (0);
}