diff options
| -rw-r--r-- | sys/net/bpf.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/sys/net/bpf.c b/sys/net/bpf.c index 21d4969..f8f605b 100644 --- a/sys/net/bpf.c +++ b/sys/net/bpf.c @@ -898,22 +898,28 @@ bpfwrite(struct cdev *dev, struct uio *uio, int ioflag) } /* - * Reset a descriptor by flushing its packet buffer and clearing the - * receive and drop counts. + * Reset a descriptor by flushing its packet buffer and clearing the receive + * and drop counts. This is doable for kernel-only buffers, but with + * zero-copy buffers, we can't write to (or rotate) buffers that are + * currently owned by userspace. It would be nice if we could encapsulate + * this logic in the buffer code rather than here. */ static void reset_d(struct bpf_d *d) { mtx_assert(&d->bd_mtx, MA_OWNED); - if (d->bd_hbuf) { + + if ((d->bd_hbuf != NULL) && + (d->bd_bufmode != BPF_BUFMODE_ZBUF || bpf_canfreebuf(d))) { /* Free the hold buffer. */ d->bd_fbuf = d->bd_hbuf; d->bd_hbuf = NULL; + d->bd_hlen = 0; bpf_buf_reclaimed(d); } - d->bd_slen = 0; - d->bd_hlen = 0; + if (bpf_canwritebuf(d)) + d->bd_slen = 0; d->bd_rcount = 0; d->bd_dcount = 0; d->bd_fcount = 0; |
