Add experimental BPF Just-In-Time compiler for amd64 and i386.

Use the following kernel configuration option to enable:

	options BPF_JITTER

If you want to use bpf_filter() instead (e. g., debugging), do:

	sysctl net.bpf.jitter.enable=0

to turn it off.

Currently BIOCSETWF and bpf_mtap2() are unsupported, and bpf_mtap() is
partially supported because 1) no need, 2) avoid expensive m_copydata(9).

Obtained from:	WinPcap 3.1 (for i386)

1 files changed, 80 insertions, 0 deletions

diff --git a/sys/net/bpf_jitter.h b/sys/net/bpf_jitter.h
new file mode 100644
index 0000000..0ae64f9
--- /dev/null
+++ b/sys/net/bpf_jitter.h
@@ -0,0 +1,80 @@
+/*-
+ * Copyright (c) 2002 - 2003 NetGroup, Politecnico di Torino (Italy)
+ * Copyright (c) 2005 Jung-uk Kim <jkim@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the Politecnico di Torino nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS intERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _NET_BPF_JITTER_H_
+#define _NET_BPF_JITTER_H_
+
+MALLOC_DECLARE(M_BPFJIT);
+
+/*
+ * Prototype of a filtering function created by the jitter.
+ *
+ * The syntax and the meaning of the parameters is analogous to the one of
+ * bpf_filter(). Notice that the filter is not among the parameters because
+ * it is hardwired in the function.
+ */
+typedef u_int (*bpf_filter_func)(u_char *, u_int, u_int);
+
+/* Structure describing a native filtering program created by the jitter. */
+typedef struct bpf_jit_filter {
+	/* The native filtering binary, in the form of a bpf_filter_func. */
+	bpf_filter_func	func;
+
+	int		*mem;
+} bpf_jit_filter;
+
+/*
+ * BPF jitter, builds a machine function from a BPF program.
+ *
+ * param fp	The BPF pseudo-assembly filter that will be translated
+ *		into native code.
+ * param nins	Number of instructions of the input filter.
+ * return	The bpf_jit_filter structure containing the native filtering
+ *		binary.
+ *
+ * bpf_jitter allocates the buffers for the new native filter and
+ * then translates the program pointed by fp calling bpf_jit_compile().
+ */
+bpf_jit_filter	*bpf_jitter(struct bpf_insn *fp, int nins);
+
+/*
+ * Deletes a filtering function that was previously created by bpf_jitter().
+ *
+ * param filter	The filter to destroy.
+ *
+ * This function frees the variuos buffers (code, memory, etc.) associated
+ * with a filtering function.
+ */
+void		bpf_destroy_jit_filter(bpf_jit_filter *filter);
+
+#endif	/* _NET_BPF_JITTER_H_ */