cxgb4: add parser to translate u32 filters to internal spec

Parse information sent by u32 into internal filter specification.
Add support for parsing several fields in IPv4, IPv6, TCP, and UDP.
Signed-off-by: NRahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: NHariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h

+/*
+ * This file is part of the Chelsio T4 Ethernet driver for Linux.
+ *
+ * Copyright (c) 2016 Chelsio Communications, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - 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.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef __CXGB4_TC_U32_PARSE_H
+#define __CXGB4_TC_U32_PARSE_H
+
+struct cxgb4_match_field {
+	int off; /* Offset from the beginning of the header to match */
+	/* Fill the value/mask pair in the spec if matched */
+	int (*val)(struct ch_filter_specification *f, u32 val, u32 mask);
+};
+
+/* IPv4 match fields */
+static inline int cxgb4_fill_ipv4_tos(struct ch_filter_specification *f,
+				      u32 val, u32 mask)
+{
+	f->val.tos  = (ntohl(val)  >> 16) & 0x000000FF;
+	f->mask.tos = (ntohl(mask) >> 16) & 0x000000FF;
+
+	return 0;
+}
+
+static inline int cxgb4_fill_ipv4_frag(struct ch_filter_specification *f,
+				       u32 val, u32 mask)
+{
+	u32 mask_val;
+	u8 frag_val;
+
+	frag_val = (ntohl(val) >> 13) & 0x00000007;
+	mask_val = ntohl(mask) & 0x0000FFFF;
+
+	if (frag_val == 0x1 && mask_val != 0x3FFF) { /* MF set */
+		f->val.frag = 1;
+		f->mask.frag = 1;
+	} else if (frag_val == 0x2 && mask_val != 0x3FFF) { /* DF set */
+		f->val.frag = 0;
+		f->mask.frag = 1;
+	} else {
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static inline int cxgb4_fill_ipv4_proto(struct ch_filter_specification *f,
+					u32 val, u32 mask)
+{
+	f->val.proto  = (ntohl(val)  >> 16) & 0x000000FF;
+	f->mask.proto = (ntohl(mask) >> 16) & 0x000000FF;
+
+	return 0;
+}
+
+static inline int cxgb4_fill_ipv4_src_ip(struct ch_filter_specification *f,
+					 u32 val, u32 mask)
+{
+	memcpy(&f->val.fip[0],  &val,  sizeof(u32));
+	memcpy(&f->mask.fip[0], &mask, sizeof(u32));
+
+	return 0;
+}
+
+static inline int cxgb4_fill_ipv4_dst_ip(struct ch_filter_specification *f,
+					 u32 val, u32 mask)
+{
+	memcpy(&f->val.lip[0],  &val,  sizeof(u32));
+	memcpy(&f->mask.lip[0], &mask, sizeof(u32));
+
+	return 0;
+}
+
+static const struct cxgb4_match_field cxgb4_ipv4_fields[] = {
+	{ .off = 0,  .val = cxgb4_fill_ipv4_tos },
+	{ .off = 4,  .val = cxgb4_fill_ipv4_frag },
+	{ .off = 8,  .val = cxgb4_fill_ipv4_proto },
+	{ .off = 12, .val = cxgb4_fill_ipv4_src_ip },
+	{ .off = 16, .val = cxgb4_fill_ipv4_dst_ip },
+	{ .val = NULL }
+};
+
+/* IPv6 match fields */
+static inline int cxgb4_fill_ipv6_tos(struct ch_filter_specification *f,
+				      u32 val, u32 mask)
+{
+	f->val.tos  = (ntohl(val)  >> 20) & 0x000000FF;
+	f->mask.tos = (ntohl(mask) >> 20) & 0x000000FF;
+
+	return 0;
+}
+
+static inline int cxgb4_fill_ipv6_proto(struct ch_filter_specification *f,
+					u32 val, u32 mask)
+{
+	f->val.proto  = (ntohl(val)  >> 8) & 0x000000FF;
+	f->mask.proto = (ntohl(mask) >> 8) & 0x000000FF;
+
+	return 0;
+}
+
+static inline int cxgb4_fill_ipv6_src_ip0(struct ch_filter_specification *f,
+					  u32 val, u32 mask)
+{
+	memcpy(&f->val.fip[0],  &val,  sizeof(u32));
+	memcpy(&f->mask.fip[0], &mask, sizeof(u32));
+
+	return 0;
+}
+
+static inline int cxgb4_fill_ipv6_src_ip1(struct ch_filter_specification *f,
+					  u32 val, u32 mask)
+{
+	memcpy(&f->val.fip[4],  &val,  sizeof(u32));
+	memcpy(&f->mask.fip[4], &mask, sizeof(u32));
+
+	return 0;
+}
+
+static inline int cxgb4_fill_ipv6_src_ip2(struct ch_filter_specification *f,
+					  u32 val, u32 mask)
+{
+	memcpy(&f->val.fip[8],  &val,  sizeof(u32));
+	memcpy(&f->mask.fip[8], &mask, sizeof(u32));
+
+	return 0;
+}
+
+static inline int cxgb4_fill_ipv6_src_ip3(struct ch_filter_specification *f,
+					  u32 val, u32 mask)
+{
+	memcpy(&f->val.fip[12],  &val,  sizeof(u32));
+	memcpy(&f->mask.fip[12], &mask, sizeof(u32));
+
+	return 0;
+}
+
+static inline int cxgb4_fill_ipv6_dst_ip0(struct ch_filter_specification *f,
+					  u32 val, u32 mask)
+{
+	memcpy(&f->val.lip[0],  &val,  sizeof(u32));
+	memcpy(&f->mask.lip[0], &mask, sizeof(u32));
+
+	return 0;
+}
+
+static inline int cxgb4_fill_ipv6_dst_ip1(struct ch_filter_specification *f,
+					  u32 val, u32 mask)
+{
+	memcpy(&f->val.lip[4],  &val,  sizeof(u32));
+	memcpy(&f->mask.lip[4], &mask, sizeof(u32));
+
+	return 0;
+}
+
+static inline int cxgb4_fill_ipv6_dst_ip2(struct ch_filter_specification *f,
+					  u32 val, u32 mask)
+{
+	memcpy(&f->val.lip[8],  &val,  sizeof(u32));
+	memcpy(&f->mask.lip[8], &mask, sizeof(u32));
+
+	return 0;
+}
+
+static inline int cxgb4_fill_ipv6_dst_ip3(struct ch_filter_specification *f,
+					  u32 val, u32 mask)
+{
+	memcpy(&f->val.lip[12],  &val,  sizeof(u32));
+	memcpy(&f->mask.lip[12], &mask, sizeof(u32));
+
+	return 0;
+}
+
+static const struct cxgb4_match_field cxgb4_ipv6_fields[] = {
+	{ .off = 0,  .val = cxgb4_fill_ipv6_tos },
+	{ .off = 4,  .val = cxgb4_fill_ipv6_proto },
+	{ .off = 8,  .val = cxgb4_fill_ipv6_src_ip0 },
+	{ .off = 12, .val = cxgb4_fill_ipv6_src_ip1 },
+	{ .off = 16, .val = cxgb4_fill_ipv6_src_ip2 },
+	{ .off = 20, .val = cxgb4_fill_ipv6_src_ip3 },
+	{ .off = 24, .val = cxgb4_fill_ipv6_dst_ip0 },
+	{ .off = 28, .val = cxgb4_fill_ipv6_dst_ip1 },
+	{ .off = 32, .val = cxgb4_fill_ipv6_dst_ip2 },
+	{ .off = 36, .val = cxgb4_fill_ipv6_dst_ip3 },
+	{ .val = NULL }
+};
+
+/* TCP/UDP match */
+static inline int cxgb4_fill_l4_ports(struct ch_filter_specification *f,
+				      u32 val, u32 mask)
+{
+	f->val.fport  = ntohl(val)  >> 16;
+	f->mask.fport = ntohl(mask) >> 16;
+	f->val.lport  = ntohl(val)  & 0x0000FFFF;
+	f->mask.lport = ntohl(mask) & 0x0000FFFF;
+
+	return 0;
+};
+
+static const struct cxgb4_match_field cxgb4_tcp_fields[] = {
+	{ .off = 0, .val = cxgb4_fill_l4_ports },
+	{ .val = NULL }
+};
+
+static const struct cxgb4_match_field cxgb4_udp_fields[] = {
+	{ .off = 0, .val = cxgb4_fill_l4_ports },
+	{ .val = NULL }
+};
+
+struct cxgb4_next_header {
+	unsigned int offset; /* Offset to next header */
+	/* offset, shift, and mask added to offset above
+	 * to get to next header.  Useful when using a header
+	 * field's value to jump to next header such as IHL field
+	 * in IPv4 header.
+	 */
+	unsigned int offoff;
+	u32 shift;
+	u32 mask;
+	/* match criteria to make this jump */
+	unsigned int match_off;
+	u32 match_val;
+	u32 match_mask;
+	/* location of jump to make */
+	const struct cxgb4_match_field *jump;
+};
+
+/* Accept a rule with a jump to transport layer header based on IHL field in
+ * IPv4 header.
+ */
+static const struct cxgb4_next_header cxgb4_ipv4_jumps[] = {
+	{ .offset = 0, .offoff = 0, .shift = 6, .mask = 0xF,
+	  .match_off = 8, .match_val = 0x600, .match_mask = 0xFF00,
+	  .jump = cxgb4_tcp_fields },
+	{ .offset = 0, .offoff = 0, .shift = 6, .mask = 0xF,
+	  .match_off = 8, .match_val = 0x1100, .match_mask = 0xFF00,
+	  .jump = cxgb4_udp_fields },
+	{ .jump = NULL }
+};
+
+/* Accept a rule with a jump directly past the 40 Bytes of IPv6 fixed header
+ * to get to transport layer header.
+ */
+static const struct cxgb4_next_header cxgb4_ipv6_jumps[] = {
+	{ .offset = 0x28, .offoff = 0, .shift = 0, .mask = 0,
+	  .match_off = 4, .match_val = 0x60000, .match_mask = 0xFF0000,
+	  .jump = cxgb4_tcp_fields },
+	{ .offset = 0x28, .offoff = 0, .shift = 0, .mask = 0,
+	  .match_off = 4, .match_val = 0x110000, .match_mask = 0xFF0000,
+	  .jump = cxgb4_udp_fields },
+	{ .jump = NULL }
+};
+#endif /* __CXGB4_TC_U32_PARSE_H */