Aren/NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Put a lock around pipe->pipe_peer.

Browse Source
This commit is contained in:
ad 2007-03-12 21:31:03 +00:00
parent 0e442136ae
commit c81da4c01d
3 changed files with 69 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
sys/kern/init_main.c
View File

@ -1,4 +1,4 @@
/* $NetBSD: init_main.c,v 1.299 2007/03/10 15:56:21 ad Exp $ */
/* $NetBSD: init_main.c,v 1.300 2007/03/12 21:31:11 ad Exp $ */
/*
* Copyright (c) 1982, 1986, 1989, 1991, 1992, 1993
@ -71,7 +71,7 @@
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: init_main.c,v 1.299 2007/03/10 15:56:21 ad Exp $");
__KERNEL_RCSID(0, "$NetBSD: init_main.c,v 1.300 2007/03/12 21:31:11 ad Exp $");
#include "opt_ipsec.h"
#include "opt_kcont.h"
@ -144,9 +144,7 @@ __KERNEL_RCSID(0, "$NetBSD: init_main.c,v 1.299 2007/03/10 15:56:21 ad Exp $");
#if NRND > 0
#include <sys/rnd.h>
#endif
#ifndef PIPE_SOCKETPAIR
#include <sys/pipe.h>
#endif
#ifdef LKM
#include <sys/lkm.h>
#endif
@ -457,6 +455,9 @@ main(void)
/* Initialize system accouting. */
acct_init();
/* Initialize pipes. */
pipe_init();
/* Kick off timeout driven events by calling first time. */
schedcpu(NULL);

77
sys/kern/sys_pipe.c
View File

@ -1,4 +1,4 @@
/* $NetBSD: sys_pipe.c,v 1.81 2007/03/12 19:05:05 ad Exp $ */
/* $NetBSD: sys_pipe.c,v 1.82 2007/03/12 21:31:12 ad Exp $ */
/*-
* Copyright (c) 2003, 2007 The NetBSD Foundation, Inc.
@ -83,7 +83,7 @@
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: sys_pipe.c,v 1.81 2007/03/12 19:05:05 ad Exp $");
__KERNEL_RCSID(0, "$NetBSD: sys_pipe.c,v 1.82 2007/03/12 21:31:12 ad Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@ -193,6 +193,15 @@ static void pipe_loan_free(struct pipe *);
static POOL_INIT(pipe_pool, sizeof(struct pipe), 0, 0, 0, "pipepl",
&pool_allocator_nointr, IPL_NONE);
static krwlock_t pipe_peer_lock;
void
pipe_init(void)
{
rw_init(&pipe_peer_lock);
}
/*
* The pipe system call for the DTYPE_PIPE type of pipes
*/
@ -1089,6 +1098,7 @@ pipe_ioctl(struct file *fp, u_long cmd, void *data, struct lwp *l)
case FIONWRITE:
/* Look at other side */
rw_enter(&pipe_peer_lock, RW_WRITER);
pipe = pipe->pipe_peer;
mutex_enter(&pipe->pipe_lock);
#ifndef PIPE_NODIRECT
@ -1098,10 +1108,12 @@ pipe_ioctl(struct file *fp, u_long cmd, void *data, struct lwp *l)
#endif
*(int *)data = pipe->pipe_buffer.cnt;
mutex_exit(&pipe->pipe_lock);
rw_exit(&pipe_peer_lock);
return (0);
case FIONSPACE:
/* Look at other side */
rw_enter(&pipe_peer_lock, RW_WRITER);
pipe = pipe->pipe_peer;
mutex_enter(&pipe->pipe_lock);
#ifndef PIPE_NODIRECT
@ -1115,8 +1127,9 @@ pipe_ioctl(struct file *fp, u_long cmd, void *data, struct lwp *l)
else
#endif
*(int *)data = pipe->pipe_buffer.size -
pipe->pipe_buffer.cnt;
pipe->pipe_buffer.cnt;
mutex_exit(&pipe->pipe_lock);
rw_exit(&pipe_peer_lock);
return (0);
case TIOCSPGRP:
@ -1193,6 +1206,8 @@ pipe_stat(struct file *fp, struct stat *ub, struct lwp *l)
{
struct pipe *pipe = (struct pipe *)fp->f_data;
rw_enter(&pipe_peer_lock, RW_WRITER);
memset((void *)ub, 0, sizeof(*ub));
ub->st_mode = S_IFIFO | S_IRUSR | S_IWUSR;
ub->st_blksize = pipe->pipe_buffer.size;
@ -1205,6 +1220,9 @@ pipe_stat(struct file *fp, struct stat *ub, struct lwp *l)
TIMEVAL_TO_TIMESPEC(&pipe->pipe_ctime, &ub->st_ctimespec);
ub->st_uid = kauth_cred_geteuid(fp->f_cred);
ub->st_gid = kauth_cred_getegid(fp->f_cred);
rw_exit(&pipe_peer_lock);
/*
* Left as 0: st_dev, st_ino, st_nlink, st_rdev, st_flags, st_gen.
* XXX (st_dev, st_ino) should be unique.
@ -1258,7 +1276,8 @@ pipeclose(struct file *fp, struct pipe *pipe)
if (pipe == NULL)
return;
retry:
retry:
rw_enter(&pipe_peer_lock, RW_READER);
mutex_enter(&pipe->pipe_lock);
pipeselwakeup(pipe, pipe, POLL_HUP);
@ -1268,10 +1287,17 @@ retry:
* we want to close it down.
*/
pipe->pipe_state |= PIPE_EOF;
while (pipe->pipe_busy) {
cv_broadcast(&pipe->pipe_cv);
pipe->pipe_state |= PIPE_WANTCLOSE;
cv_wait_sig(&pipe->pipe_cv, &pipe->pipe_lock);
if (pipe->pipe_busy) {
rw_exit(&pipe_peer_lock);
while (pipe->pipe_busy) {
cv_broadcast(&pipe->pipe_cv);
pipe->pipe_state |= PIPE_WANTCLOSE;
cv_wait_sig(&pipe->pipe_cv, &pipe->pipe_lock);
}
if (!rw_tryenter(&pipe_peer_lock, RW_READER)) {
mutex_exit(&pipe->pipe_lock);
goto retry;
}
}
/*
@ -1281,6 +1307,7 @@ retry:
/* Deal with race for peer */
if (mutex_tryenter(&ppipe->pipe_lock) == 0) {
mutex_exit(&pipe->pipe_lock);
rw_exit(&pipe_peer_lock);
goto retry;
}
pipeselwakeup(ppipe, ppipe, POLL_HUP);
@ -1294,6 +1321,7 @@ retry:
KASSERT((pipe->pipe_state & PIPE_LOCKFL) == 0);
mutex_exit(&pipe->pipe_lock);
rw_exit(&pipe_peer_lock);
/*
* free resources
@ -1310,15 +1338,18 @@ filt_pipedetach(struct knote *kn)
{
struct pipe *pipe = (struct pipe *)kn->kn_fp->f_data;
rw_enter(&pipe_peer_lock, RW_WRITER);
switch(kn->kn_filter) {
case EVFILT_WRITE:
/* need the peer structure, not our own */
pipe = pipe->pipe_peer;
/* XXXSMP: race for peer */
/* if reader end already closed, just return */
if (pipe == NULL)
if (pipe == NULL) {
rw_exit(&pipe_peer_lock);
return;
}
break;
default:
@ -1334,6 +1365,7 @@ filt_pipedetach(struct knote *kn)
mutex_enter(&pipe->pipe_lock);
SLIST_REMOVE(&pipe->pipe_sel.sel_klist, kn, knote, kn_selnext);
mutex_exit(&pipe->pipe_lock);
rw_exit(&pipe_peer_lock);
}
/*ARGSUSED*/
@ -1341,7 +1373,10 @@ static int
filt_piperead(struct knote *kn, long hint)
{
struct pipe *rpipe = (struct pipe *)kn->kn_fp->f_data;
struct pipe *wpipe = rpipe->pipe_peer;
struct pipe *wpipe;
rw_enter(&pipe_peer_lock, RW_WRITER);
wpipe = rpipe->pipe_peer;
if ((hint & NOTE_SUBMIT) == 0)
mutex_enter(&rpipe->pipe_lock);
@ -1349,16 +1384,17 @@ filt_piperead(struct knote *kn, long hint)
if ((kn->kn_data == 0) && (rpipe->pipe_state & PIPE_DIRECTW))
kn->kn_data = rpipe->pipe_map.cnt;
/* XXXSMP: race for peer */
if ((rpipe->pipe_state & PIPE_EOF) ||
(wpipe == NULL) || (wpipe->pipe_state & PIPE_EOF)) {
kn->kn_flags |= EV_EOF;
if ((hint & NOTE_SUBMIT) == 0)
mutex_exit(&rpipe->pipe_lock);
rw_exit(&pipe_peer_lock);
return (1);
}
if ((hint & NOTE_SUBMIT) == 0)
mutex_exit(&rpipe->pipe_lock);
rw_exit(&pipe_peer_lock);
return (kn->kn_data > 0);
}
@ -1367,16 +1403,19 @@ static int
filt_pipewrite(struct knote *kn, long hint)
{
struct pipe *rpipe = (struct pipe *)kn->kn_fp->f_data;
struct pipe *wpipe = rpipe->pipe_peer;
struct pipe *wpipe;
rw_enter(&pipe_peer_lock, RW_WRITER);
wpipe = rpipe->pipe_peer;
if ((hint & NOTE_SUBMIT) == 0)
mutex_enter(&rpipe->pipe_lock);
/* XXXSMP: race for peer */
if ((wpipe == NULL) || (wpipe->pipe_state & PIPE_EOF)) {
kn->kn_data = 0;
kn->kn_flags |= EV_EOF;
if ((hint & NOTE_SUBMIT) == 0)
mutex_exit(&rpipe->pipe_lock);
rw_exit(&pipe_peer_lock);
return (1);
}
kn->kn_data = wpipe->pipe_buffer.size - wpipe->pipe_buffer.cnt;
@ -1385,6 +1424,7 @@ filt_pipewrite(struct knote *kn, long hint)
if ((hint & NOTE_SUBMIT) == 0)
mutex_exit(&rpipe->pipe_lock);
rw_exit(&pipe_peer_lock);
return (kn->kn_data >= PIPE_BUF);
}
@ -1399,28 +1439,33 @@ pipe_kqfilter(struct file *fp, struct knote *kn)
{
struct pipe *pipe;
rw_enter(&pipe_peer_lock, RW_WRITER);
pipe = (struct pipe *)kn->kn_fp->f_data;
switch (kn->kn_filter) {
case EVFILT_READ:
kn->kn_fop = &pipe_rfiltops;
break;
case EVFILT_WRITE:
kn->kn_fop = &pipe_wfiltops;
/* XXXSMP: race for peer */
pipe = pipe->pipe_peer;
if (pipe == NULL) {
/* other end of pipe has been closed */
rw_exit(&pipe_peer_lock);
return (EBADF);
}
break;
default:
rw_exit(&pipe_peer_lock);
return (1);
}
kn->kn_hook = pipe;
kn->kn_hook = pipe;
mutex_enter(&pipe->pipe_lock);
SLIST_INSERT_HEAD(&pipe->pipe_sel.sel_klist, kn, kn_selnext);
mutex_exit(&pipe->pipe_lock);
rw_exit(&pipe_peer_lock);
return (0);
}

5
sys/sys/pipe.h
View File

@ -1,4 +1,4 @@
/* $NetBSD: pipe.h,v 1.20 2007/03/12 16:20:53 ad Exp $ */
/* $NetBSD: pipe.h,v 1.21 2007/03/12 21:31:03 ad Exp $ */
/*
* Copyright (c) 1996 John S. Dyson
@ -139,7 +139,8 @@ struct pipe {
}
#ifdef _KERNEL
int sysctl_dopipe(int *, u_int, void *, size_t *, void *, size_t);
int sysctl_dopipe(int *, u_int, void *, size_t *, void *, size_t);
void pipe_init(void);
#endif /* _KERNEL */
#endif /* !_SYS_PIPE_H_ */