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Diffstat (limited to 'freebsd/sys/kern/sys_pipe.c')
-rwxr-xr-xfreebsd/sys/kern/sys_pipe.c52
1 files changed, 24 insertions, 28 deletions
diff --git a/freebsd/sys/kern/sys_pipe.c b/freebsd/sys/kern/sys_pipe.c
index cdfff76d..e20c67ea 100755
--- a/freebsd/sys/kern/sys_pipe.c
+++ b/freebsd/sys/kern/sys_pipe.c
@@ -802,11 +802,9 @@ pipe_read(struct file *fp, struct uio *uio, struct ucred *active_cred,
/*
* Direct copy, bypassing a kernel buffer.
*/
- } else if ((size = rpipe->pipe_map.cnt) &&
- (rpipe->pipe_state & PIPE_DIRECTW)) {
+ } else if ((size = rpipe->pipe_map.cnt) != 0) {
if (size > uio->uio_resid)
size = (u_int) uio->uio_resid;
-
PIPE_UNLOCK(rpipe);
error = uiomove_fromphys(rpipe->pipe_map.ms,
rpipe->pipe_map.pos, size, uio);
@@ -984,32 +982,33 @@ pipe_build_write_buffer(struct pipe *wpipe, struct uio *uio)
u_int size;
int i;
- PIPE_LOCK_ASSERT(wpipe, MA_NOTOWNED);
- KASSERT(wpipe->pipe_state & PIPE_DIRECTW,
- ("Clone attempt on non-direct write pipe!"));
+ PIPE_LOCK_ASSERT(wpipe, MA_OWNED);
+ KASSERT((wpipe->pipe_state & PIPE_DIRECTW) == 0,
+ ("%s: PIPE_DIRECTW set on %p", __func__, wpipe));
+ KASSERT(wpipe->pipe_map.cnt == 0,
+ ("%s: pipe map for %p contains residual data", __func__, wpipe));
if (uio->uio_iov->iov_len > wpipe->pipe_buffer.size)
size = wpipe->pipe_buffer.size;
else
size = uio->uio_iov->iov_len;
- if ((i = vm_fault_quick_hold_pages(&curproc->p_vmspace->vm_map,
+ wpipe->pipe_state |= PIPE_DIRECTW;
+ PIPE_UNLOCK(wpipe);
+ i = vm_fault_quick_hold_pages(&curproc->p_vmspace->vm_map,
(vm_offset_t)uio->uio_iov->iov_base, size, VM_PROT_READ,
- wpipe->pipe_map.ms, PIPENPAGES)) < 0)
+ wpipe->pipe_map.ms, PIPENPAGES);
+ PIPE_LOCK(wpipe);
+ if (i < 0) {
+ wpipe->pipe_state &= ~PIPE_DIRECTW;
return (EFAULT);
+ }
-/*
- * set up the control block
- */
wpipe->pipe_map.npages = i;
wpipe->pipe_map.pos =
((vm_offset_t) uio->uio_iov->iov_base) & PAGE_MASK;
wpipe->pipe_map.cnt = size;
-/*
- * and update the uio data
- */
-
uio->uio_iov->iov_len -= size;
uio->uio_iov->iov_base = (char *)uio->uio_iov->iov_base + size;
if (uio->uio_iov->iov_len == 0)
@@ -1029,6 +1028,8 @@ pipe_destroy_write_buffer(struct pipe *wpipe)
PIPE_LOCK_ASSERT(wpipe, MA_OWNED);
KASSERT((wpipe->pipe_state & PIPE_DIRECTW) != 0,
("%s: PIPE_DIRECTW not set on %p", __func__, wpipe));
+ KASSERT(wpipe->pipe_map.cnt == 0,
+ ("%s: pipe map for %p contains residual data", __func__, wpipe));
wpipe->pipe_state &= ~PIPE_DIRECTW;
vm_page_unhold_pages(wpipe->pipe_map.ms, wpipe->pipe_map.npages);
@@ -1054,6 +1055,7 @@ pipe_clone_write_buffer(struct pipe *wpipe)
size = wpipe->pipe_map.cnt;
pos = wpipe->pipe_map.pos;
+ wpipe->pipe_map.cnt = 0;
wpipe->pipe_buffer.in = size;
wpipe->pipe_buffer.out = 0;
@@ -1111,7 +1113,6 @@ retry:
else
goto retry;
}
- wpipe->pipe_map.cnt = 0; /* transfer not ready yet */
if (wpipe->pipe_buffer.cnt > 0) {
if (wpipe->pipe_state & PIPE_WANTR) {
wpipe->pipe_state &= ~PIPE_WANTR;
@@ -1128,19 +1129,15 @@ retry:
goto retry;
}
- wpipe->pipe_state |= PIPE_DIRECTW;
-
- PIPE_UNLOCK(wpipe);
error = pipe_build_write_buffer(wpipe, uio);
- PIPE_LOCK(wpipe);
if (error) {
- wpipe->pipe_state &= ~PIPE_DIRECTW;
pipeunlock(wpipe);
goto error1;
}
while (wpipe->pipe_map.cnt != 0) {
if (wpipe->pipe_state & PIPE_EOF) {
+ wpipe->pipe_map.cnt = 0;
pipe_destroy_write_buffer(wpipe);
pipeselwakeup(wpipe);
pipeunlock(wpipe);
@@ -1294,7 +1291,7 @@ pipe_write(struct file *fp, struct uio *uio, struct ucred *active_cred,
* pipe buffer. We break out if a signal occurs or the
* reader goes away.
*/
- if (wpipe->pipe_state & PIPE_DIRECTW) {
+ if (wpipe->pipe_map.cnt != 0) {
if (wpipe->pipe_state & PIPE_WANTR) {
wpipe->pipe_state &= ~PIPE_WANTR;
wakeup(wpipe);
@@ -1590,7 +1587,7 @@ pipe_ioctl(struct file *fp, u_long cmd, void *data, struct ucred *active_cred,
PIPE_UNLOCK(mpipe);
return (0);
}
- if (mpipe->pipe_state & PIPE_DIRECTW)
+ if (mpipe->pipe_map.cnt != 0)
*(int *)data = mpipe->pipe_map.cnt;
else
*(int *)data = mpipe->pipe_buffer.cnt;
@@ -1667,8 +1664,7 @@ pipe_poll(struct file *fp, int events, struct ucred *active_cred,
#else /* __rtems__ */
if (rtems_bsd_libio_flags_to_fflag(fp->f_io.flags) & FREAD && events & (POLLIN | POLLRDNORM))
#endif /* __rtems__ */
- if ((rpipe->pipe_state & PIPE_DIRECTW) ||
- (rpipe->pipe_buffer.cnt > 0))
+ if (rpipe->pipe_map.cnt > 0 || rpipe->pipe_buffer.cnt > 0)
revents |= events & (POLLIN | POLLRDNORM);
#ifndef __rtems__
@@ -1678,7 +1674,7 @@ pipe_poll(struct file *fp, int events, struct ucred *active_cred,
#endif /* __rtems__ */
if (wpipe->pipe_present != PIPE_ACTIVE ||
(wpipe->pipe_state & PIPE_EOF) ||
- (((wpipe->pipe_state & PIPE_DIRECTW) == 0) &&
+ ((wpipe->pipe_state & PIPE_DIRECTW) == 0 &&
((wpipe->pipe_buffer.size - wpipe->pipe_buffer.cnt) >= PIPE_BUF ||
wpipe->pipe_buffer.size == 0)))
revents |= events & (POLLOUT | POLLWRNORM);
@@ -1796,7 +1792,7 @@ pipe_stat(struct pipe *pipe, struct stat *ub)
#endif /* __rtems__ */
ub->st_mode = S_IFIFO;
ub->st_blksize = PAGE_SIZE;
- if (pipe->pipe_state & PIPE_DIRECTW)
+ if (pipe->pipe_map.cnt != 0)
ub->st_size = pipe->pipe_map.cnt;
else
ub->st_size = pipe->pipe_buffer.cnt;
@@ -2085,7 +2081,7 @@ filt_piperead(struct knote *kn, long hint)
PIPE_LOCK_ASSERT(rpipe, MA_OWNED);
kn->kn_data = rpipe->pipe_buffer.cnt;
- if ((kn->kn_data == 0) && (rpipe->pipe_state & PIPE_DIRECTW))
+ if (kn->kn_data == 0)
kn->kn_data = rpipe->pipe_map.cnt;
if ((rpipe->pipe_state & PIPE_EOF) ||
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-28 23:36:29 +0000