Function bpf_canwritebuf

freebsd/net/bpf.c:448–458

* Allow the buffer model to indicate that the current store buffer is * immutable, regardless of the appearance of space. Return (1) if the * buffer is writable, and (0) if not. */

 * buffer is writable, and (0) if not.
 */
static int
bpf_canwritebuf(struct bpf_d *d)
{
	BPFD_LOCK_ASSERT(d);

	switch (d->bd_bufmode) {
	case BPF_BUFMODE_ZBUF:
		return (bpf_zerocopy_canwritebuf(d));
	}
	return (1);
}

/*
 * Notify buffer model that an attempt to write to the store buffer has