1 /** @file
2
3 Implementation of the SNP.Transmit() function and its private helpers if any.
4
5 Copyright (C) 2013, Red Hat, Inc.
6 Copyright (c) 2006 - 2013, Intel Corporation. All rights reserved.<BR>
7
8 This program and the accompanying materials are licensed and made available
9 under the terms and conditions of the BSD License which accompanies this
10 distribution. The full text of the license may be found at
11 http://opensource.org/licenses/bsd-license.php
12
13 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT
14 WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
15
16 **/
17
18 #include <Library/BaseLib.h>
19 #include <Library/BaseMemoryLib.h>
20 #include <Library/UefiBootServicesTableLib.h>
21
22 #include "VirtioNet.h"
23
24 /**
25 Places a packet in the transmit queue of a network interface.
26
27 @param This The protocol instance pointer.
28 @param HeaderSize The size, in bytes, of the media header to be filled in by
29 the Transmit() function. If HeaderSize is non-zero, then
30 it must be equal to This->Mode->MediaHeaderSize and the
31 DestAddr and Protocol parameters must not be NULL.
32 @param BufferSize The size, in bytes, of the entire packet (media header and
33 data) to be transmitted through the network interface.
34 @param Buffer A pointer to the packet (media header followed by data) to
35 be transmitted. This parameter cannot be NULL. If
36 HeaderSize is zero, then the media header in Buffer must
37 already be filled in by the caller. If HeaderSize is
38 non-zero, then the media header will be filled in by the
39 Transmit() function.
40 @param SrcAddr The source HW MAC address. If HeaderSize is zero, then
41 this parameter is ignored. If HeaderSize is non-zero and
42 SrcAddr is NULL, then This->Mode->CurrentAddress is used
43 for the source HW MAC address.
44 @param DestAddr The destination HW MAC address. If HeaderSize is zero,
45 then this parameter is ignored.
46 @param Protocol The type of header to build. If HeaderSize is zero, then
47 this parameter is ignored. See RFC 1700, section "Ether
48 Types", for examples.
49
50 @retval EFI_SUCCESS The packet was placed on the transmit queue.
51 @retval EFI_NOT_STARTED The network interface has not been started.
52 @retval EFI_NOT_READY The network interface is too busy to accept
53 this transmit request.
54 @retval EFI_BUFFER_TOO_SMALL The BufferSize parameter is too small.
55 @retval EFI_INVALID_PARAMETER One or more of the parameters has an
56 unsupported value.
57 @retval EFI_DEVICE_ERROR The command could not be sent to the network
58 interface.
59 @retval EFI_UNSUPPORTED This function is not supported by the network
60 interface.
61
62 **/
63
64 EFI_STATUS
65 EFIAPI
VirtioNetTransmit(IN EFI_SIMPLE_NETWORK_PROTOCOL * This,IN UINTN HeaderSize,IN UINTN BufferSize,IN VOID * Buffer,IN EFI_MAC_ADDRESS * SrcAddr OPTIONAL,IN EFI_MAC_ADDRESS * DestAddr OPTIONAL,IN UINT16 * Protocol OPTIONAL)66 VirtioNetTransmit (
67 IN EFI_SIMPLE_NETWORK_PROTOCOL *This,
68 IN UINTN HeaderSize,
69 IN UINTN BufferSize,
70 IN /* +OUT! */ VOID *Buffer,
71 IN EFI_MAC_ADDRESS *SrcAddr OPTIONAL,
72 IN EFI_MAC_ADDRESS *DestAddr OPTIONAL,
73 IN UINT16 *Protocol OPTIONAL
74 )
75 {
76 VNET_DEV *Dev;
77 EFI_TPL OldTpl;
78 EFI_STATUS Status;
79 UINT16 DescIdx;
80 UINT16 AvailIdx;
81
82 if (This == NULL || BufferSize == 0 || Buffer == NULL) {
83 return EFI_INVALID_PARAMETER;
84 }
85
86 Dev = VIRTIO_NET_FROM_SNP (This);
87 OldTpl = gBS->RaiseTPL (TPL_CALLBACK);
88 switch (Dev->Snm.State) {
89 case EfiSimpleNetworkStopped:
90 Status = EFI_NOT_STARTED;
91 goto Exit;
92 case EfiSimpleNetworkStarted:
93 Status = EFI_DEVICE_ERROR;
94 goto Exit;
95 default:
96 break;
97 }
98
99 if (BufferSize < Dev->Snm.MediaHeaderSize) {
100 Status = EFI_BUFFER_TOO_SMALL;
101 goto Exit;
102 }
103 if (BufferSize > Dev->Snm.MediaHeaderSize + Dev->Snm.MaxPacketSize) {
104 Status = EFI_INVALID_PARAMETER;
105 goto Exit;
106 }
107
108 //
109 // check if we have room for transmission
110 //
111 ASSERT (Dev->TxCurPending <= Dev->TxMaxPending);
112 if (Dev->TxCurPending == Dev->TxMaxPending) {
113 Status = EFI_NOT_READY;
114 goto Exit;
115 }
116
117 //
118 // the caller may want us to fill in the media header:
119 // dst MAC, src MAC, Ethertype
120 //
121 if (HeaderSize != 0) {
122 UINT8 *Ptr;
123
124 if (HeaderSize != Dev->Snm.MediaHeaderSize ||
125 DestAddr == NULL || Protocol == NULL) {
126 Status = EFI_INVALID_PARAMETER;
127 goto Exit;
128 }
129 Ptr = Buffer;
130 ASSERT (SIZE_OF_VNET (Mac) <= sizeof (EFI_MAC_ADDRESS));
131
132 CopyMem (Ptr, DestAddr, SIZE_OF_VNET (Mac));
133 Ptr += SIZE_OF_VNET (Mac);
134
135 CopyMem (Ptr,
136 (SrcAddr == NULL) ? &Dev->Snm.CurrentAddress : SrcAddr,
137 SIZE_OF_VNET (Mac));
138 Ptr += SIZE_OF_VNET (Mac);
139
140 *Ptr++ = (UINT8) (*Protocol >> 8);
141 *Ptr++ = (UINT8) *Protocol;
142
143 ASSERT ((UINTN) (Ptr - (UINT8 *) Buffer) == Dev->Snm.MediaHeaderSize);
144 }
145
146 //
147 // virtio-0.9.5, 2.4.1 Supplying Buffers to The Device
148 //
149 DescIdx = Dev->TxFreeStack[Dev->TxCurPending++];
150 Dev->TxRing.Desc[DescIdx + 1].Addr = (UINTN) Buffer;
151 Dev->TxRing.Desc[DescIdx + 1].Len = (UINT32) BufferSize;
152
153 //
154 // the available index is never written by the host, we can read it back
155 // without a barrier
156 //
157 AvailIdx = *Dev->TxRing.Avail.Idx;
158 Dev->TxRing.Avail.Ring[AvailIdx++ % Dev->TxRing.QueueSize] = DescIdx;
159
160 MemoryFence ();
161 *Dev->TxRing.Avail.Idx = AvailIdx;
162
163 MemoryFence ();
164 Status = Dev->VirtIo->SetQueueNotify (Dev->VirtIo, VIRTIO_NET_Q_TX);
165
166 Exit:
167 gBS->RestoreTPL (OldTpl);
168 return Status;
169 }
170