xref: /dpdk/lib/gso/gso_common.h (revision daa02b5c)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2017 Intel Corporation
3  */
4 
5 #ifndef _GSO_COMMON_H_
6 #define _GSO_COMMON_H_
7 
8 #include <stdint.h>
9 
10 #include <rte_mbuf.h>
11 #include <rte_ip.h>
12 #include <rte_tcp.h>
13 #include <rte_udp.h>
14 
15 #define IS_FRAGMENTED(frag_off) (((frag_off) & RTE_IPV4_HDR_OFFSET_MASK) != 0 \
16 		|| ((frag_off) & RTE_IPV4_HDR_MF_FLAG) == RTE_IPV4_HDR_MF_FLAG)
17 
18 #define TCP_HDR_PSH_MASK ((uint8_t)0x08)
19 #define TCP_HDR_FIN_MASK ((uint8_t)0x01)
20 
21 #define IS_IPV4_TCP(flag) (((flag) & (RTE_MBUF_F_TX_TCP_SEG | RTE_MBUF_F_TX_IPV4)) == \
22 		(RTE_MBUF_F_TX_TCP_SEG | RTE_MBUF_F_TX_IPV4))
23 
24 #define IS_IPV4_VXLAN_TCP4(flag) (((flag) & (RTE_MBUF_F_TX_TCP_SEG | RTE_MBUF_F_TX_IPV4 | \
25 				RTE_MBUF_F_TX_OUTER_IPV4 | RTE_MBUF_F_TX_TUNNEL_MASK)) == \
26 		(RTE_MBUF_F_TX_TCP_SEG | RTE_MBUF_F_TX_IPV4 | RTE_MBUF_F_TX_OUTER_IPV4 | \
27 		 RTE_MBUF_F_TX_TUNNEL_VXLAN))
28 
29 #define IS_IPV4_VXLAN_UDP4(flag) (((flag) & (RTE_MBUF_F_TX_UDP_SEG | RTE_MBUF_F_TX_IPV4 | \
30 				RTE_MBUF_F_TX_OUTER_IPV4 | RTE_MBUF_F_TX_TUNNEL_MASK)) == \
31 		(RTE_MBUF_F_TX_UDP_SEG | RTE_MBUF_F_TX_IPV4 | RTE_MBUF_F_TX_OUTER_IPV4 | \
32 		 RTE_MBUF_F_TX_TUNNEL_VXLAN))
33 
34 #define IS_IPV4_GRE_TCP4(flag) (((flag) & (RTE_MBUF_F_TX_TCP_SEG | RTE_MBUF_F_TX_IPV4 | \
35 				RTE_MBUF_F_TX_OUTER_IPV4 | RTE_MBUF_F_TX_TUNNEL_MASK)) == \
36 		(RTE_MBUF_F_TX_TCP_SEG | RTE_MBUF_F_TX_IPV4 | RTE_MBUF_F_TX_OUTER_IPV4 | \
37 		 RTE_MBUF_F_TX_TUNNEL_GRE))
38 
39 #define IS_IPV4_UDP(flag) (((flag) & (RTE_MBUF_F_TX_UDP_SEG | RTE_MBUF_F_TX_IPV4)) == \
40 		(RTE_MBUF_F_TX_UDP_SEG | RTE_MBUF_F_TX_IPV4))
41 
42 /**
43  * Internal function which updates the UDP header of a packet, following
44  * segmentation. This is required to update the header's datagram length field.
45  *
46  * @param pkt
47  *  The packet containing the UDP header.
48  * @param udp_offset
49  *  The offset of the UDP header from the start of the packet.
50  */
51 static inline void
update_udp_header(struct rte_mbuf * pkt,uint16_t udp_offset)52 update_udp_header(struct rte_mbuf *pkt, uint16_t udp_offset)
53 {
54 	struct rte_udp_hdr *udp_hdr;
55 
56 	udp_hdr = (struct rte_udp_hdr *)(rte_pktmbuf_mtod(pkt, char *) +
57 			udp_offset);
58 	udp_hdr->dgram_len = rte_cpu_to_be_16(pkt->pkt_len - udp_offset);
59 }
60 
61 /**
62  * Internal function which updates the TCP header of a packet, following
63  * segmentation. This is required to update the header's 'sent' sequence
64  * number, and also to clear 'PSH' and 'FIN' flags for non-tail segments.
65  *
66  * @param pkt
67  *  The packet containing the TCP header.
68  * @param l4_offset
69  *  The offset of the TCP header from the start of the packet.
70  * @param sent_seq
71  *  The sent sequence number.
72  * @param non-tail
73  *  Indicates whether or not this is a tail segment.
74  */
75 static inline void
update_tcp_header(struct rte_mbuf * pkt,uint16_t l4_offset,uint32_t sent_seq,uint8_t non_tail)76 update_tcp_header(struct rte_mbuf *pkt, uint16_t l4_offset, uint32_t sent_seq,
77 		uint8_t non_tail)
78 {
79 	struct rte_tcp_hdr *tcp_hdr;
80 
81 	tcp_hdr = (struct rte_tcp_hdr *)(rte_pktmbuf_mtod(pkt, char *) +
82 			l4_offset);
83 	tcp_hdr->sent_seq = rte_cpu_to_be_32(sent_seq);
84 	if (likely(non_tail))
85 		tcp_hdr->tcp_flags &= (~(TCP_HDR_PSH_MASK |
86 					TCP_HDR_FIN_MASK));
87 }
88 
89 /**
90  * Internal function which updates the IPv4 header of a packet, following
91  * segmentation. This is required to update the header's 'total_length' field,
92  * to reflect the reduced length of the now-segmented packet. Furthermore, the
93  * header's 'packet_id' field must be updated to reflect the new ID of the
94  * now-segmented packet.
95  *
96  * @param pkt
97  *  The packet containing the IPv4 header.
98  * @param l3_offset
99  *  The offset of the IPv4 header from the start of the packet.
100  * @param id
101  *  The new ID of the packet.
102  */
103 static inline void
update_ipv4_header(struct rte_mbuf * pkt,uint16_t l3_offset,uint16_t id)104 update_ipv4_header(struct rte_mbuf *pkt, uint16_t l3_offset, uint16_t id)
105 {
106 	struct rte_ipv4_hdr *ipv4_hdr;
107 
108 	ipv4_hdr = (struct rte_ipv4_hdr *)(rte_pktmbuf_mtod(pkt, char *) +
109 			l3_offset);
110 	ipv4_hdr->total_length = rte_cpu_to_be_16(pkt->pkt_len - l3_offset);
111 	ipv4_hdr->packet_id = rte_cpu_to_be_16(id);
112 }
113 
114 /**
115  * Internal function which divides the input packet into small segments.
116  * Each of the newly-created segments is organized as a two-segment MBUF,
117  * where the first segment is a standard mbuf, which stores a copy of
118  * packet header, and the second is an indirect mbuf which points to a
119  * section of data in the input packet.
120  *
121  * @param pkt
122  *  Packet to segment.
123  * @param pkt_hdr_offset
124  *  Packet header offset, measured in bytes.
125  * @param pyld_unit_size
126  *  The max payload length of a GSO segment.
127  * @param direct_pool
128  *  MBUF pool used for allocating direct buffers for output segments.
129  * @param indirect_pool
130  *  MBUF pool used for allocating indirect buffers for output segments.
131  * @param pkts_out
132  *  Pointer array used to keep the mbuf addresses of output segments. If
133  *  the memory space in pkts_out is insufficient, gso_do_segment() fails
134  *  and returns -EINVAL.
135  * @param nb_pkts_out
136  *  The max number of items that pkts_out can keep.
137  *
138  * @return
139  *  - The number of segments created in the event of success.
140  *  - Return -ENOMEM if run out of memory in MBUF pools.
141  *  - Return -EINVAL for invalid parameters.
142  */
143 int gso_do_segment(struct rte_mbuf *pkt,
144 		uint16_t pkt_hdr_offset,
145 		uint16_t pyld_unit_size,
146 		struct rte_mempool *direct_pool,
147 		struct rte_mempool *indirect_pool,
148 		struct rte_mbuf **pkts_out,
149 		uint16_t nb_pkts_out);
150 #endif
151