1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2017 Intel Corporation
*/
#ifndef _RTE_GSO_H_
#define _RTE_GSO_H_
/**
* @file
* Interface to GSO library
*/
#ifdef __cplusplus
extern "C" {
#endif
#include <stdint.h>
#include <rte_mbuf.h>
/* Minimum GSO segment size. */
#define RTE_GSO_SEG_SIZE_MIN (sizeof(struct ether_hdr) + \
sizeof(struct ipv4_hdr) + sizeof(struct tcp_hdr) + 1)
/* GSO flags for rte_gso_ctx. */
#define RTE_GSO_FLAG_IPID_FIXED (1ULL << 0)
/**< Use fixed IP ids for output GSO segments. Setting
* 0 indicates using incremental IP ids.
*/
/**
* GSO context structure.
*/
struct rte_gso_ctx {
struct rte_mempool *direct_pool;
/**< MBUF pool for allocating direct buffers, which are used
* to store packet headers for GSO segments.
*/
struct rte_mempool *indirect_pool;
/**< MBUF pool for allocating indirect buffers, which are used
* to locate packet payloads for GSO segments. The indirect
* buffer doesn't contain any data, but simply points to an
* offset within the packet to segment.
*/
uint64_t flag;
/**< flag that controls specific attributes of output segments,
* such as the type of IP ID generated (i.e. fixed or incremental).
*/
uint32_t gso_types;
/**< the bit mask of required GSO types. The GSO library
* uses the same macros as that of describing device TX
* offloading capabilities (i.e. DEV_TX_OFFLOAD_*_TSO) for
* gso_types.
*
* For example, if applications want to segment TCP/IPv4
* packets, set DEV_TX_OFFLOAD_TCP_TSO in gso_types.
*/
uint16_t gso_size;
/**< maximum size of an output GSO segment, including packet
* header and payload, measured in bytes. Must exceed
* RTE_GSO_SEG_SIZE_MIN.
*/
};
/**
* Segmentation function, which supports processing of both single- and
* multi- MBUF packets.
*
* Note that we refer to the packets that are segmented from the input
* packet as 'GSO segments'. rte_gso_segment() doesn't check if the
* input packet has correct checksums, and doesn't update checksums for
* output GSO segments. Additionally, it doesn't process IP fragment
* packets.
*
* Before calling rte_gso_segment(), applications must set proper ol_flags
* for the packet. The GSO library uses the same macros as that of TSO.
* For example, set PKT_TX_TCP_SEG and PKT_TX_IPV4 in ol_flags to segment
* a TCP/IPv4 packet. If rte_gso_segment() succeeds, the PKT_TX_TCP_SEG
* flag is removed for all GSO segments and the input packet.
*
* Each of the newly-created GSO segments is organized as a two-segment
* MBUF, where the first segment is a standard MBUF, which stores a copy
* of packet header, and the second is an indirect MBUF which points to
* a section of data in the input packet. Since each GSO segment has
* multiple MBUFs (i.e. typically 2 MBUFs), the driver of the interface which
* the GSO segments are sent to should support transmission of multi-segment
* packets.
*
* If the input packet is GSO'd, its mbuf refcnt reduces by 1. Therefore,
* when all GSO segments are freed, the input packet is freed automatically.
*
* If the memory space in pkts_out or MBUF pools is insufficient, this
* function fails, and it returns (-1) * errno. Otherwise, GSO succeeds,
* and this function returns the number of output GSO segments filled in
* pkts_out.
*
* @param pkt
* The packet mbuf to segment.
* @param ctx
* GSO context object pointer.
* @param pkts_out
* Pointer array used to store the MBUF addresses of output GSO
* segments, when rte_gso_segment() succeeds.
* @param nb_pkts_out
* The max number of items that pkts_out can keep.
*
* @return
* - The number of GSO segments filled in pkts_out on success.
* - Return -ENOMEM if run out of memory in MBUF pools.
* - Return -EINVAL for invalid parameters.
*/
int rte_gso_segment(struct rte_mbuf *pkt,
const struct rte_gso_ctx *ctx,
struct rte_mbuf **pkts_out,
uint16_t nb_pkts_out);
#ifdef __cplusplus
}
#endif
#endif /* _RTE_GSO_H_ */
|
