--- libaitio/src/bpf.c	2013/06/26 12:30:17	1.1.2.15
+++ libaitio/src/bpf.c	2013/06/26 13:33:55	1.1.2.16
@@ -154,7 +154,7 @@ io_etherOpen(const char *csIface, int flags, int whdr,
 			close(eth);
 			return -1;
 		}
-		if (ioctl(eth, BIOCSETZBUF, (struct bpf_zbuf*) *zcbuf) == -1) {
+		if (ioctl(eth, BIOCSETZBUF, *zcbuf) == -1) {
 			LOGERR;
 			io_etherClose(eth, zcbuf);
 			return -1;
@@ -231,11 +231,10 @@ chkZCbuf(struct bpf_zbuf_header * __restrict bzh)
 	return (bzh->bzh_user_gen != atomic_load_acq_int(&bzh->bzh_kernel_gen));
 }
 
-static inline ssize_t
-nextZCbuf(void ** __restrict zcache, struct bpf_zbuf * __restrict zbuf, 
-		const void * __restrict buf)
+static inline size_t
+nextZCbuf(void ** __restrict zcache, struct bpf_zbuf * __restrict zbuf)
 {
-	ssize_t rlen = -1;
+	size_t rlen = 0;
 	struct bpf_zbuf_header *bzh;
 
 	if (!*zcache || *zcache == zbuf->bz_bufb) {
@@ -243,21 +242,13 @@ nextZCbuf(void ** __restrict zcache, struct bpf_zbuf *
 		if (chkZCbuf(bzh)) {
 			rlen = atomic_load_acq_int(&bzh->bzh_kernel_len);
 			*zcache = zbuf->bz_bufa;
-			if (buf)
-				buf = ((caddr_t) *zcache) + sizeof(struct bpf_zbuf_header);
-			ackZCbuf(bzh);
-		} else
-			io_SetErr(EAGAIN, "kernel owns the buffer A");
+		}
 	} else if (*zcache == zbuf->bz_bufa) {
 		bzh = (struct bpf_zbuf_header *) zbuf->bz_bufb;
 		if (chkZCbuf(bzh)) {
 			rlen = atomic_load_acq_int(&bzh->bzh_kernel_len);
 			*zcache = zbuf->bz_bufb;
-			if (buf)
-				buf = ((caddr_t) *zcache) + sizeof(struct bpf_zbuf_header);
-			ackZCbuf(bzh);
-		} else
-			io_SetErr(EAGAIN, "kernel owns the buffer B");
+		}
 	}
 
 	return rlen;
@@ -278,6 +269,9 @@ io_etherRecv(int eth, void * __restrict buf, size_t bu
 {
 	ssize_t rlen = 0;
 	void *zcache = NULL;
+#ifdef __FreeBSD__
+	struct bpf_zbuf_header *bzh;
+#endif
 
 	if (!buf || !buflen) {
 		io_SetErr(EINVAL, "invalid arguments");
@@ -290,8 +284,14 @@ io_etherRecv(int eth, void * __restrict buf, size_t bu
 			LOGERR;
 	} else {
 #ifdef __FreeBSD__
-		rlen = nextZCbuf(&zcache, (struct bpf_zbuf*) zcbuf, buf);
+		rlen = (ssize_t) nextZCbuf(&zcache, (struct bpf_zbuf*) zcbuf);
+		if (rlen > 0) {
+			bzh = (struct bpf_zbuf_header*) zcache;
+			memcpy(buf, zcache + sizeof(struct bpf_zbuf_header), buflen);
+			ackZCbuf(bzh);
+		}
 #else
+		rlen = -1;
 		io_SetErr(ENOTSUP, "bpf zero copy buffer mode is not supported");
 #endif
 	}