3 Implementation of the SNP.Receive() function and its private helpers if any.
5 Copyright (C) 2013, Red Hat, Inc.
6 Copyright (c) 2006 - 2013, Intel Corporation. All rights reserved.<BR>
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
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.
18 #include <Library/BaseLib.h>
19 #include <Library/BaseMemoryLib.h>
20 #include <Library/UefiBootServicesTableLib.h>
22 #include "VirtioNet.h"
25 Receives a packet from a network interface.
27 @param This The protocol instance pointer.
28 @param HeaderSize The size, in bytes, of the media header received on the
29 network interface. If this parameter is NULL, then the
30 media header size will not be returned.
31 @param BufferSize On entry, the size, in bytes, of Buffer. On exit, the
32 size, in bytes, of the packet that was received on the
34 @param Buffer A pointer to the data buffer to receive both the media
36 @param SrcAddr The source HW MAC address. If this parameter is NULL, the
37 HW MAC source address will not be extracted from the media
39 @param DestAddr The destination HW MAC address. If this parameter is NULL,
40 the HW MAC destination address will not be extracted from
42 @param Protocol The media header type. If this parameter is NULL, then the
43 protocol will not be extracted from the media header. See
44 RFC 1700 section "Ether Types" for examples.
46 @retval EFI_SUCCESS The received data was stored in Buffer, and
47 BufferSize has been updated to the number of
49 @retval EFI_NOT_STARTED The network interface has not been started.
50 @retval EFI_NOT_READY The network interface is too busy to accept
51 this transmit request.
52 @retval EFI_BUFFER_TOO_SMALL The BufferSize parameter is too small.
53 @retval EFI_INVALID_PARAMETER One or more of the parameters has an
55 @retval EFI_DEVICE_ERROR The command could not be sent to the network
57 @retval EFI_UNSUPPORTED This function is not supported by the network
65 IN EFI_SIMPLE_NETWORK_PROTOCOL
*This
,
66 OUT UINTN
*HeaderSize OPTIONAL
,
67 IN OUT UINTN
*BufferSize
,
69 OUT EFI_MAC_ADDRESS
*SrcAddr OPTIONAL
,
70 OUT EFI_MAC_ADDRESS
*DestAddr OPTIONAL
,
71 OUT UINT16
*Protocol OPTIONAL
84 EFI_STATUS NotifyStatus
;
86 if (This
== NULL
|| BufferSize
== NULL
|| Buffer
== NULL
) {
87 return EFI_INVALID_PARAMETER
;
90 Dev
= VIRTIO_NET_FROM_SNP (This
);
91 OldTpl
= gBS
->RaiseTPL (TPL_CALLBACK
);
92 switch (Dev
->Snm
.State
) {
93 case EfiSimpleNetworkStopped
:
94 Status
= EFI_NOT_STARTED
;
96 case EfiSimpleNetworkStarted
:
97 Status
= EFI_DEVICE_ERROR
;
104 // virtio-0.9.5, 2.4.2 Receiving Used Buffers From the Device
107 RxCurUsed
= *Dev
->RxRing
.Used
.Idx
;
109 if (Dev
->RxLastUsed
== RxCurUsed
) {
110 Status
= EFI_NOT_READY
;
114 UsedElemIdx
= Dev
->RxLastUsed
% Dev
->RxRing
.QueueSize
;
115 DescIdx
= Dev
->RxRing
.Used
.UsedElem
[UsedElemIdx
].Id
;
116 RxLen
= Dev
->RxRing
.Used
.UsedElem
[UsedElemIdx
].Len
;
119 // the virtio-net request header must be complete; we skip it
121 ASSERT (RxLen
>= Dev
->RxRing
.Desc
[DescIdx
].Len
);
122 RxLen
-= Dev
->RxRing
.Desc
[DescIdx
].Len
;
124 // the host must not have filled in more data than requested
126 ASSERT (RxLen
<= Dev
->RxRing
.Desc
[DescIdx
+ 1].Len
);
128 OrigBufferSize
= *BufferSize
;
131 if (OrigBufferSize
< RxLen
) {
132 Status
= EFI_BUFFER_TOO_SMALL
;
133 goto Exit
; // keep the packet
136 if (RxLen
< Dev
->Snm
.MediaHeaderSize
) {
137 Status
= EFI_DEVICE_ERROR
;
138 goto RecycleDesc
; // drop useless short packet
141 if (HeaderSize
!= NULL
) {
142 *HeaderSize
= Dev
->Snm
.MediaHeaderSize
;
145 RxPtr
= (UINT8
*)(UINTN
) Dev
->RxRing
.Desc
[DescIdx
+ 1].Addr
;
146 CopyMem (Buffer
, RxPtr
, RxLen
);
148 if (DestAddr
!= NULL
) {
149 CopyMem (DestAddr
, RxPtr
, SIZE_OF_VNET (VhdrMac
));
151 RxPtr
+= SIZE_OF_VNET (VhdrMac
);
153 if (SrcAddr
!= NULL
) {
154 CopyMem (SrcAddr
, RxPtr
, SIZE_OF_VNET (VhdrMac
));
156 RxPtr
+= SIZE_OF_VNET (VhdrMac
);
158 if (Protocol
!= NULL
) {
159 *Protocol
= (UINT16
) ((RxPtr
[0] << 8) | RxPtr
[1]);
161 RxPtr
+= sizeof (UINT16
);
163 Status
= EFI_SUCCESS
;
169 // virtio-0.9.5, 2.4.1 Supplying Buffers to The Device
171 AvailIdx
= *Dev
->RxRing
.Avail
.Idx
;
172 Dev
->RxRing
.Avail
.Ring
[AvailIdx
++ % Dev
->RxRing
.QueueSize
] =
176 *Dev
->RxRing
.Avail
.Idx
= AvailIdx
;
179 NotifyStatus
= VIRTIO_CFG_WRITE (Dev
, Generic
.VhdrQueueNotify
,
182 if (!EFI_ERROR (Status
)) { // earlier error takes precedence
183 Status
= NotifyStatus
;
187 gBS
->RestoreTPL (OldTpl
);