1 /**************************************************************************/
2 /* */
3 /* Copyright (c) Microsoft Corporation. All rights reserved. */
4 /* */
5 /* This software is licensed under the Microsoft Software License */
6 /* Terms for Microsoft Azure RTOS. Full text of the license can be */
7 /* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
8 /* and in the root directory of this software. */
9 /* */
10 /**************************************************************************/
11
12
13 /**************************************************************************/
14 /**************************************************************************/
15 /** */
16 /** NetX Component */
17 /** */
18 /** Packet Pool Management (Packet) */
19 /** */
20 /**************************************************************************/
21 /**************************************************************************/
22
23 #define NX_SOURCE_CODE
24
25
26 /* Include necessary system files. */
27
28 #include "nx_api.h"
29 #include "nx_ip.h"
30 #include "nx_packet.h"
31
32 #ifdef FEATURE_NX_IPV6
33 #include "nx_ipv6.h"
34 #endif
35
36
37 /**************************************************************************/
38 /* */
39 /* FUNCTION RELEASE */
40 /* */
41 /* _nx_packet_transmit_release PORTABLE C */
42 /* 6.1 */
43 /* AUTHOR */
44 /* */
45 /* Yuxin Zhou, Microsoft Corporation */
46 /* */
47 /* DESCRIPTION */
48 /* */
49 /* This function releases a transmitted packet chain back to the */
50 /* appropriate packet pool. If the packet is a TCP packet, it is */
51 /* simply marked as completed. The actual release is deferred to */
52 /* the TCP component. */
53 /* */
54 /* INPUT */
55 /* */
56 /* packet_ptr Pointer of packet to release */
57 /* */
58 /* OUTPUT */
59 /* */
60 /* status Completion status */
61 /* */
62 /* CALLS */
63 /* */
64 /* _nx_packet_release Release packet back to pool */
65 /* */
66 /* CALLED BY */
67 /* */
68 /* Application Code */
69 /* */
70 /* RELEASE HISTORY */
71 /* */
72 /* DATE NAME DESCRIPTION */
73 /* */
74 /* 05-19-2020 Yuxin Zhou Initial Version 6.0 */
75 /* 09-30-2020 Yuxin Zhou Modified comment(s), */
76 /* resulting in version 6.1 */
77 /* */
78 /**************************************************************************/
_nx_packet_transmit_release(NX_PACKET * packet_ptr)79 UINT _nx_packet_transmit_release(NX_PACKET *packet_ptr)
80 {
81
82 TX_INTERRUPT_SAVE_AREA
83
84 UINT status;
85
86
87 /* If trace is enabled, insert this event into the trace buffer. */
88 NX_TRACE_IN_LINE_INSERT(NX_TRACE_PACKET_TRANSMIT_RELEASE, packet_ptr, packet_ptr -> nx_packet_union_next.nx_packet_tcp_queue_next, (packet_ptr -> nx_packet_pool_owner) -> nx_packet_pool_available, 0, NX_TRACE_PACKET_EVENTS, 0, 0);
89
90 /* Disable interrupts temporarily. */
91 TX_DISABLE
92
93 /* Add debug information. */
94 NX_PACKET_DEBUG(__FILE__, __LINE__, packet_ptr);
95
96 /* Determine if the packet is a queued TCP data packet. Such packets cannot be released
97 immediately, since they may need to be resent. */
98 /*lint -e{923} suppress cast of ULONG to pointer. */
99 if ((packet_ptr -> nx_packet_union_next.nx_packet_tcp_queue_next != ((NX_PACKET *)NX_PACKET_ALLOCATED)) &&
100 (packet_ptr -> nx_packet_union_next.nx_packet_tcp_queue_next != ((NX_PACKET *)NX_PACKET_FREE)))
101 {
102
103 /* Yes, this is indeed a TCP packet. Just mark this with the NX_DRIVER_TX_DONE
104 value to let the TCP layer know it is no longer queued up. */
105 /*lint -e{923} suppress cast of ULONG to pointer. */
106 packet_ptr -> nx_packet_queue_next = (NX_PACKET *)NX_DRIVER_TX_DONE;
107
108 /* Remove the IP header and adjust the length. */
109 packet_ptr -> nx_packet_prepend_ptr += packet_ptr -> nx_packet_ip_header_length;
110 packet_ptr -> nx_packet_length -= packet_ptr -> nx_packet_ip_header_length;
111
112 /* Reset the IP header length. */
113 packet_ptr -> nx_packet_ip_header_length = 0;
114
115 /* Restore interrupts. */
116 TX_RESTORE
117
118 /* Return success. */
119 status = NX_SUCCESS;
120 }
121 else
122 {
123
124 /* Restore interrupts. */
125 TX_RESTORE
126
127 /* Call the actual packet release function. */
128 status = _nx_packet_release(packet_ptr);
129 }
130
131 /* Return completion status. */
132 return(status);
133 }
134
135
