OvmfPkg: VirtioNetDxe: add SNP.Initialize and shared dependencies

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14410 6f19259b-4bc3-4df7-8a09-765794883524

2 files changed, 512 insertions, 0 deletions

diff --git a/OvmfPkg/VirtioNetDxe/SnpInitialize.c b/OvmfPkg/VirtioNetDxe/SnpInitialize.c
new file mode 100644
index 0000000000..39282d9a4a
--- /dev/null
+++ b/OvmfPkg/VirtioNetDxe/SnpInitialize.c
@@ -0,0 +1,459 @@
+/** @file

+

+  Implementation of the SNP.Initialize() function and its private helpers if

+  any.

+

+  Copyright (C) 2013, Red Hat, Inc.

+  Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>

+

+  This program and the accompanying materials are licensed and made available

+  under the terms and conditions of the BSD License which accompanies this

+  distribution. The full text of the license may be found at

+  http://opensource.org/licenses/bsd-license.php

+

+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT

+  WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

+

+**/

+

+#include <Library/BaseLib.h>

+#include <Library/MemoryAllocationLib.h>

+#include <Library/UefiBootServicesTableLib.h>

+

+#include "VirtioNet.h"

+

+/**

+  Initialize a virtio ring for a specific transfer direction of the virtio-net

+  device.

+

+  This function may only be called by VirtioNetInitialize().

+

+  @param[in,out] Dev       The VNET_DEV driver instance about to enter the

+                           EfiSimpleNetworkInitialized state.

+  @param[in]     Selector  Identifies the transfer direction (virtio queue) of

+                           the network device.

+  @param[out]    Ring      The virtio-ring inside the VNET_DEV structure,

+                           corresponding to Selector.

+

+  @retval EFI_UNSUPPORTED  The queue size reported by the virtio-net device is

+                           too small.

+  @return                  Status codes from VIRTIO_CFG_WRITE(),

+                           VIRTIO_CFG_READ() and VirtioRingInit().

+  @retval EFI_SUCCESS      Ring initialized.

+*/

+

+STATIC

+EFI_STATUS

+EFIAPI

+VirtioNetInitRing (

+  IN OUT VNET_DEV *Dev,

+  IN     UINT16   Selector,

+  OUT    VRING    *Ring

+  )

+{

+  EFI_STATUS Status;

+  UINT16     QueueSize;

+

+  //

+  // step 4b -- allocate selected queue

+  //

+  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrQueueSelect, Selector);

+  if (EFI_ERROR (Status)) {

+    return Status;

+  }

+  Status = VIRTIO_CFG_READ (Dev, Generic.VhdrQueueSize, &QueueSize);

+  if (EFI_ERROR (Status)) {

+    return Status;

+  }

+  //

+  // For each packet (RX and TX alike), we need two descriptors:

+  // one for the virtio-net request header, and another one for the data

+  //

+  if (QueueSize < 2) {

+    return EFI_UNSUPPORTED;

+  }

+  Status = VirtioRingInit (QueueSize, Ring);

+  if (EFI_ERROR (Status)) {

+    return Status;

+  }

+

+  //

+  // step 4c -- report GPFN (guest-physical frame number) of queue

+  //

+  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrQueueAddress,

+             (UINTN) Ring->Base >> EFI_PAGE_SHIFT);

+  if (EFI_ERROR (Status)) {

+    VirtioRingUninit (Ring);

+  }

+  return Status;

+}

+

+

+/**

+  Set up static scaffolding for the VirtioNetTransmit() and

+  VirtioNetGetStatus() SNP methods.

+

+  This function may only be called by VirtioNetInitialize().

+

+  The structures laid out and resources configured include:

+  - fully populate the TX queue with a static pattern of virtio descriptor

+    chains,

+  - tracking of heads of free descriptor chains from the above,

+  - one common virtio-net request header (never modified by the host) for all

+    pending TX packets,

+  - select polling over TX interrupt.

+

+  @param[in,out] Dev       The VNET_DEV driver instance about to enter the

+                           EfiSimpleNetworkInitialized state.

+

+  @retval EFI_OUT_OF_RESOURCES  Failed to allocate the stack to track the heads

+                                of free descriptor chains.

+  @retval EFI_SUCCESS           TX setup successful.

+*/

+

+STATIC

+EFI_STATUS

+EFIAPI

+VirtioNetInitTx (

+  IN OUT VNET_DEV *Dev

+  )

+{

+  UINTN PktIdx;

+

+  Dev->TxMaxPending = MIN (Dev->TxRing.QueueSize / 2, VNET_MAX_PENDING);

+  Dev->TxCurPending = 0;

+  Dev->TxFreeStack  = AllocatePool (Dev->TxMaxPending *

+                        sizeof *Dev->TxFreeStack);

+  if (Dev->TxFreeStack == NULL) {

+    return EFI_OUT_OF_RESOURCES;

+  }

+

+  for (PktIdx = 0; PktIdx < Dev->TxMaxPending; ++PktIdx) {

+    UINT16 DescIdx;

+

+    DescIdx = (UINT16) (2 * PktIdx);

+    Dev->TxFreeStack[PktIdx] = DescIdx;

+

+    //

+    // For each possibly pending packet, lay out the descriptor for the common

+    // (unmodified by the host) virtio-net request header.

+    //

+    Dev->TxRing.Desc[DescIdx].Addr  = (UINTN) &Dev->TxSharedReq;

+    Dev->TxRing.Desc[DescIdx].Len   = sizeof Dev->TxSharedReq;

+    Dev->TxRing.Desc[DescIdx].Flags = VRING_DESC_F_NEXT;

+    Dev->TxRing.Desc[DescIdx].Next  = DescIdx + 1;

+

+    //

+    // The second descriptor of each pending TX packet is updated on the fly,

+    // but it always terminates the descriptor chain of the packet.

+    //

+    Dev->TxRing.Desc[DescIdx + 1].Flags = 0;

+  }

+

+  //

+  // virtio-0.9.5, Appendix C, Packet Transmission

+  //

+  Dev->TxSharedReq.Flags   = 0;

+  Dev->TxSharedReq.GsoType = VIRTIO_NET_HDR_GSO_NONE;

+

+  //

+  // virtio-0.9.5, 2.4.2 Receiving Used Buffers From the Device

+  //

+  MemoryFence ();

+  Dev->TxLastUsed = *Dev->TxRing.Used.Idx;

+  ASSERT (Dev->TxLastUsed == 0);

+

+  //

+  // want no interrupt when a transmit completes

+  //

+  *Dev->TxRing.Avail.Flags = (UINT16) VRING_AVAIL_F_NO_INTERRUPT;

+

+  return EFI_SUCCESS;

+}

+

+

+/**

+  Set up static scaffolding for the VirtioNetReceive() SNP method and enable

+  live device operation.

+

+  This function may only be called as VirtioNetInitialize()'s final step.

+

+  The structures laid out and resources configured include:

+  - destination area for the host to write virtio-net request headers and

+    packet data into,

+  - select polling over RX interrupt,

+  - fully populate the RX queue with a static pattern of virtio descriptor

+    chains.

+

+  @param[in,out] Dev       The VNET_DEV driver instance about to enter the

+                           EfiSimpleNetworkInitialized state.

+

+  @retval EFI_OUT_OF_RESOURCES  Failed to allocate RX destination area.

+  @return                       Status codes from VIRTIO_CFG_WRITE().

+  @retval EFI_SUCCESS           RX setup successful. The device is live and may

+                                already be writing to the receive area.

+*/

+

+STATIC

+EFI_STATUS

+EFIAPI

+VirtioNetInitRx (

+  IN OUT VNET_DEV *Dev

+  )

+{

+  EFI_STATUS Status;

+  UINTN      RxBufSize;

+  UINT16     RxAlwaysPending;

+  UINTN      PktIdx;

+  UINT16     DescIdx;

+  UINT8      *RxPtr;

+

+  //

+  // For each incoming packet we must supply two descriptors:

+  // - the recipient for the virtio-net request header, plus

+  // - the recipient for the network data (which consists of Ethernet header

+  //   and Ethernet payload).

+  //

+  RxBufSize = sizeof (VIRTIO_NET_REQ) +

+              (Dev->Snm.MediaHeaderSize + Dev->Snm.MaxPacketSize);

+

+  //

+  // Limit the number of pending RX packets if the queue is big. The division

+  // by two is due to the above "two descriptors per packet" trait.

+  //

+  RxAlwaysPending = MIN (Dev->RxRing.QueueSize / 2, VNET_MAX_PENDING);

+

+  Dev->RxBuf = AllocatePool (RxAlwaysPending * RxBufSize);

+  if (Dev->RxBuf == NULL) {

+    return EFI_OUT_OF_RESOURCES;

+  }

+

+  //

+  // virtio-0.9.5, 2.4.2 Receiving Used Buffers From the Device

+  //

+  MemoryFence ();

+  Dev->RxLastUsed = *Dev->RxRing.Used.Idx;

+  ASSERT (Dev->RxLastUsed == 0);

+

+  //

+  // virtio-0.9.5, 2.4.2 Receiving Used Buffers From the Device:

+  // the host should not send interrupts, we'll poll in VirtioNetReceive()

+  // and VirtioNetIsPacketAvailable().

+  //

+  *Dev->RxRing.Avail.Flags = (UINT16) VRING_AVAIL_F_NO_INTERRUPT;

+

+  //

+  // now set up a separate, two-part descriptor chain for each RX packet, and

+  // link each chain into (from) the available ring as well

+  //

+  DescIdx = 0;

+  RxPtr = Dev->RxBuf;

+  for (PktIdx = 0; PktIdx < RxAlwaysPending; ++PktIdx) {

+    //

+    // virtio-0.9.5, 2.4.1.2 Updating the Available Ring

+    // invisible to the host until we update the Index Field

+    //

+    Dev->RxRing.Avail.Ring[PktIdx] = DescIdx;

+

+    //

+    // virtio-0.9.5, 2.4.1.1 Placing Buffers into the Descriptor Table

+    //

+    Dev->RxRing.Desc[DescIdx].Addr  = (UINTN) RxPtr;

+    Dev->RxRing.Desc[DescIdx].Len   = sizeof (VIRTIO_NET_REQ);

+    Dev->RxRing.Desc[DescIdx].Flags = VRING_DESC_F_WRITE | VRING_DESC_F_NEXT;

+    Dev->RxRing.Desc[DescIdx].Next  = DescIdx + 1;

+    RxPtr += Dev->RxRing.Desc[DescIdx++].Len;

+

+    Dev->RxRing.Desc[DescIdx].Addr  = (UINTN) RxPtr;

+    Dev->RxRing.Desc[DescIdx].Len   = RxBufSize - sizeof (VIRTIO_NET_REQ);

+    Dev->RxRing.Desc[DescIdx].Flags = VRING_DESC_F_WRITE;

+    RxPtr += Dev->RxRing.Desc[DescIdx++].Len;

+  }

+

+  //

+  // virtio-0.9.5, 2.4.1.3 Updating the Index Field

+  //

+  MemoryFence ();

+  *Dev->RxRing.Avail.Idx = RxAlwaysPending;

+

+  //

+  // At this point reception may already be running. In order to make it sure,

+  // kick the hypervisor. If we fail to kick it, we must first abort reception

+  // before tearing down anything, because reception may have been already

+  // running even without the kick.

+  //

+  // virtio-0.9.5, 2.4.1.4 Notifying the Device

+  //

+  MemoryFence ();

+  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrQueueNotify, VIRTIO_NET_Q_RX);

+

+  if (EFI_ERROR (Status)) {

+    VIRTIO_CFG_WRITE (Dev, Generic.VhdrDeviceStatus, 0);

+    FreePool (Dev->RxBuf);

+  }

+

+  return Status;

+}

+

+

+/**

+  Resets a network adapter and allocates the transmit and receive buffers

+  required by the network interface; optionally, also requests allocation  of

+  additional transmit and receive buffers.

+

+  @param  This              The protocol instance pointer.

+  @param  ExtraRxBufferSize The size, in bytes, of the extra receive buffer

+                            space that the driver should allocate for the

+                            network interface. Some network interfaces will not

+                            be able to use the extra buffer, and the caller

+                            will not know if it is actually being used.

+  @param  ExtraTxBufferSize The size, in bytes, of the extra transmit buffer

+                            space that the driver should allocate for the

+                            network interface. Some network interfaces will not

+                            be able to use the extra buffer, and the caller

+                            will not know if it is actually being used.

+

+  @retval EFI_SUCCESS           The network interface was initialized.

+  @retval EFI_NOT_STARTED       The network interface has not been started.

+  @retval EFI_OUT_OF_RESOURCES  There was not enough memory for the transmit

+                                and receive buffers.

+  @retval EFI_INVALID_PARAMETER One or more of the parameters has an

+                                unsupported value.

+  @retval EFI_DEVICE_ERROR      The command could not be sent to the network

+                                interface.

+  @retval EFI_UNSUPPORTED       This function is not supported by the network

+                                interface.

+

+**/

+

+EFI_STATUS

+EFIAPI

+VirtioNetInitialize (

+  IN EFI_SIMPLE_NETWORK_PROTOCOL *This,

+  IN UINTN                       ExtraRxBufferSize  OPTIONAL,

+  IN UINTN                       ExtraTxBufferSize  OPTIONAL

+  )

+{

+  VNET_DEV   *Dev;

+  EFI_TPL    OldTpl;

+  EFI_STATUS Status;

+  UINT8      NextDevStat;

+  UINT32     Features;

+

+  if (This == NULL) {

+    return EFI_INVALID_PARAMETER;

+  }

+  if (ExtraRxBufferSize > 0 || ExtraTxBufferSize > 0) {

+    return EFI_UNSUPPORTED;

+  }

+

+  Dev = VIRTIO_NET_FROM_SNP (This);

+  OldTpl = gBS->RaiseTPL (TPL_CALLBACK);

+  if (Dev->Snm.State != EfiSimpleNetworkStarted) {

+    Status = EFI_NOT_STARTED;

+    goto InitFailed;

+  }

+

+  //

+  // In the EfiSimpleNetworkStarted state the virtio-net device has status

+  // value 0 (= reset) -- see the state diagram, the full call chain to

+  // the end of VirtioNetGetFeatures() (considering we're here now),

+  // the DeviceFailed label below, and VirtioNetShutdown().

+  //

+  // Accordingly, the below is a subsequence of the steps found in the

+  // virtio-0.9.5 spec, 2.2.1 Device Initialization Sequence.

+  //

+  NextDevStat = VSTAT_ACK;    // step 2 -- acknowledge device presence

+  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrDeviceStatus, NextDevStat);

+  if (EFI_ERROR (Status)) {

+    goto InitFailed;

+  }

+

+  NextDevStat |= VSTAT_DRIVER; // step 3 -- we know how to drive it

+  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrDeviceStatus, NextDevStat);

+  if (EFI_ERROR (Status)) {

+    goto DeviceFailed;

+  }

+

+  //

+  // step 4a -- retrieve features. Note that we're past validating required

+  // features in VirtioNetGetFeatures().

+  //

+  Status = VIRTIO_CFG_READ (Dev, Generic.VhdrDeviceFeatureBits, &Features);

+  if (EFI_ERROR (Status)) {

+    goto DeviceFailed;

+  }

+  ASSERT (Features & VIRTIO_NET_F_MAC);

+  ASSERT (Dev->Snm.MediaPresentSupported ==

+    !!(Features & VIRTIO_NET_F_STATUS));

+

+  //

+  // step 4b, 4c -- allocate and report virtqueues

+  //

+  Status = VirtioNetInitRing (Dev, VIRTIO_NET_Q_RX, &Dev->RxRing);

+  if (EFI_ERROR (Status)) {

+    goto DeviceFailed;

+  }

+

+  Status = VirtioNetInitRing (Dev, VIRTIO_NET_Q_TX, &Dev->TxRing);

+  if (EFI_ERROR (Status)) {

+    goto ReleaseRxRing;

+  }

+

+  //

+  // step 5 -- keep only the features we want

+  //

+  Features &= VIRTIO_NET_F_MAC | VIRTIO_NET_F_STATUS;

+  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrGuestFeatureBits, Features);

+  if (EFI_ERROR (Status)) {

+    goto ReleaseTxRing;

+  }

+

+  //

+  // step 6 -- virtio-net initialization complete

+  //

+  NextDevStat |= VSTAT_DRIVER_OK;

+  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrDeviceStatus, NextDevStat);

+  if (EFI_ERROR (Status)) {

+    goto ReleaseTxRing;

+  }

+

+  Status = VirtioNetInitTx (Dev);

+  if (EFI_ERROR (Status)) {

+    goto AbortDevice;

+  }

+

+  //

+  // start receiving

+  //

+  Status = VirtioNetInitRx (Dev);

+  if (EFI_ERROR (Status)) {

+    goto ReleaseTxAux;

+  }

+

+  Dev->Snm.State = EfiSimpleNetworkInitialized;

+  gBS->RestoreTPL (OldTpl);

+  return EFI_SUCCESS;

+

+ReleaseTxAux:

+  VirtioNetShutdownTx (Dev);

+

+AbortDevice:

+  VIRTIO_CFG_WRITE (Dev, Generic.VhdrDeviceStatus, 0);

+

+ReleaseTxRing:

+  VirtioRingUninit (&Dev->TxRing);

+

+ReleaseRxRing:

+  VirtioRingUninit (&Dev->RxRing);

+

+DeviceFailed:

+  //

+  // restore device status invariant for the EfiSimpleNetworkStarted state

+  //

+  VIRTIO_CFG_WRITE (Dev, Generic.VhdrDeviceStatus, 0);

+

+InitFailed:

+  gBS->RestoreTPL (OldTpl);

+  return Status;

+}

diff --git a/OvmfPkg/VirtioNetDxe/SnpSharedHelpers.c b/OvmfPkg/VirtioNetDxe/SnpSharedHelpers.c
new file mode 100644
index 0000000000..9fedb72fdb
--- /dev/null
+++ b/OvmfPkg/VirtioNetDxe/SnpSharedHelpers.c
@@ -0,0 +1,53 @@
+/** @file

+

+  Helper functions used by at least two Simple Network Protocol methods.

+

+  Copyright (C) 2013, Red Hat, Inc.

+

+  This program and the accompanying materials are licensed and made available

+  under the terms and conditions of the BSD License which accompanies this

+  distribution. The full text of the license may be found at

+  http://opensource.org/licenses/bsd-license.php

+

+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT

+  WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

+

+**/

+

+#include <Library/MemoryAllocationLib.h>

+

+#include "VirtioNet.h"

+

+/**

+  Release RX and TX resources on the boundary of the

+  EfiSimpleNetworkInitialized state.

+

+  These functions contribute to rolling back a partial, failed initialization

+  of the virtio-net SNP driver instance, or to shutting down a fully

+  initialized, running instance.

+

+  They are only callable by the VirtioNetInitialize() and the

+  VirtioNetShutdown() SNP methods. See the state diagram in "VirtioNet.h".

+

+  @param[in,out] Dev  The VNET_DEV driver instance being shut down, or whose

+                      partial, failed initialization is being rolled back.

+*/

+

+VOID

+EFIAPI

+VirtioNetShutdownRx (

+  IN OUT VNET_DEV *Dev

+  )

+{

+  FreePool (Dev->RxBuf);

+}

+

+

+VOID

+EFIAPI

+VirtioNetShutdownTx (

+  IN OUT VNET_DEV *Dev

+  )

+{

+  FreePool (Dev->TxFreeStack);

+}