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 /** Reverse Address Resolution Protocol (RARP) */
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 #include "nx_rarp.h"
32
33 #ifndef NX_DISABLE_IPV4
34 /**************************************************************************/
35 /* */
36 /* FUNCTION RELEASE */
37 /* */
38 /* _nx_rarp_packet_deferred_receive PORTABLE C */
39 /* 6.1 */
40 /* AUTHOR */
41 /* */
42 /* Yuxin Zhou, Microsoft Corporation */
43 /* */
44 /* DESCRIPTION */
45 /* */
46 /* This function receives an RARP packet from the link driver (usually */
47 /* the link driver's input ISR) and places it in the deferred receive */
48 /* RARP packet queue. This moves the minimal receive RARP packet */
49 /* processing from the ISR to the IP helper thread. */
50 /* */
51 /* INPUT */
52 /* */
53 /* ip_ptr Pointer to IP control block */
54 /* packet_ptr Pointer to packet to send */
55 /* */
56 /* OUTPUT */
57 /* */
58 /* None */
59 /* */
60 /* CALLS */
61 /* */
62 /* tx_event_flags_set Wakeup IP helper thread */
63 /* */
64 /* CALLED BY */
65 /* */
66 /* Application I/O Driver */
67 /* */
68 /* RELEASE HISTORY */
69 /* */
70 /* DATE NAME DESCRIPTION */
71 /* */
72 /* 05-19-2020 Yuxin Zhou Initial Version 6.0 */
73 /* 09-30-2020 Yuxin Zhou Modified comment(s), */
74 /* resulting in version 6.1 */
75 /* */
76 /**************************************************************************/
_nx_rarp_packet_deferred_receive(NX_IP * ip_ptr,NX_PACKET * packet_ptr)77 VOID _nx_rarp_packet_deferred_receive(NX_IP *ip_ptr, NX_PACKET *packet_ptr)
78 {
79
80 TX_INTERRUPT_SAVE_AREA
81
82
83 /* Disable interrupts. */
84 TX_DISABLE
85
86 /* Add debug information. */
87 NX_PACKET_DEBUG(__FILE__, __LINE__, packet_ptr);
88
89 /* Check to see if RARP is enabled on this IP instance. */
90 if (!ip_ptr -> nx_ip_rarp_queue_process)
91 {
92
93 /* RARP is not enabled. */
94
95 #ifndef NX_DISABLE_RARP_INFO
96 /* Increment the RARP invalid messages count... */
97 ip_ptr -> nx_ip_rarp_invalid_messages++;
98 #endif
99
100 /* Restore interrupts. */
101 TX_RESTORE
102
103 /* Since RARP is not enabled, just release the packet. */
104 _nx_packet_release(packet_ptr);
105
106 /* Return to caller. */
107 return;
108 }
109
110 /* Check to see if the RARP deferred processing queue is empty. */
111 if (ip_ptr -> nx_ip_rarp_deferred_received_packet_head)
112 {
113
114 /* Not empty, just place the packet at the end of the RARP deferred queue. */
115 (ip_ptr -> nx_ip_rarp_deferred_received_packet_tail) -> nx_packet_queue_next = packet_ptr;
116 packet_ptr -> nx_packet_queue_next = NX_NULL;
117 ip_ptr -> nx_ip_rarp_deferred_received_packet_tail = packet_ptr;
118
119 /* Restore interrupts. */
120 TX_RESTORE
121 }
122 else
123 {
124
125 /* Empty RARP deferred receive processing queue. Just setup the head pointers and
126 set the event flags to ensure the IP helper thread looks at the RARP deferred
127 processing queue. */
128 ip_ptr -> nx_ip_rarp_deferred_received_packet_head = packet_ptr;
129 ip_ptr -> nx_ip_rarp_deferred_received_packet_tail = packet_ptr;
130 packet_ptr -> nx_packet_queue_next = NX_NULL;
131
132 /* Restore interrupts. */
133 TX_RESTORE
134
135 /* Wakeup IP helper thread to process the RARP deferred receive. */
136 tx_event_flags_set(&(ip_ptr -> nx_ip_events), NX_IP_RARP_REC_EVENT, TX_OR);
137 }
138 }
139 #endif /* !NX_DISABLE_IPV4 */
140
141
