OvmfPkg: extract VirtioLib from VirtioBlkDxe

Introduce a new library called VirtioLib, for now only collecting the
following reusable functions with as little changes as possible:

- VirtioWrite()
- VirtioRead()
- VirtioRingInit()
- VirtioRingUninit()
- AppendDesc()

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

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13842 6f19259b-4bc3-4df7-8a09-765794883524

2 files changed, 2 insertions, 319 deletions

diff --git a/OvmfPkg/VirtioBlkDxe/VirtioBlk.c b/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
index ead98272a5..eeeb4bef6e 100644
--- a/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
+++ b/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
@@ -29,148 +29,12 @@
 #include <Library/MemoryAllocationLib.h>

 #include <Library/UefiBootServicesTableLib.h>

 #include <Library/UefiLib.h>

+#include <Library/VirtioLib.h>

 

 #include "VirtioBlk.h"

 

 /**

 

-  Write a word into Region 0 of the device specified by PciIo.

-

-  Region 0 must be an iomem region. This is an internal function for the

-  VIRTIO_CFG_WRITE() macro below.

-

-  @param[in] PciIo        Target PCI device.

-

-  @param[in] FieldOffset  Destination offset.

-

-  @param[in] FieldSize    Destination field size, must be in { 1, 2, 4, 8 }.

-

-  @param[in] Value        Little endian value to write, converted to UINT64.

-                          The least significant FieldSize bytes will be used.

-

-

-  @return  Status code returned by PciIo->Io.Write().

-

-**/

-STATIC

-EFIAPI

-EFI_STATUS

-VirtioWrite (

-  IN EFI_PCI_IO_PROTOCOL *PciIo,

-  IN UINTN               FieldOffset,

-  IN UINTN               FieldSize,

-  IN UINT64              Value

-  )

-{

-  UINTN                     Count;

-  EFI_PCI_IO_PROTOCOL_WIDTH Width;

-

-  Count = 1;

-  switch (FieldSize) {

-    case 1:

-      Width = EfiPciIoWidthUint8;

-      break;

-

-    case 2:

-      Width = EfiPciIoWidthUint16;

-      break;

-

-    case 8:

-      Count = 2;

-      // fall through

-

-    case 4:

-      Width = EfiPciIoWidthUint32;

-      break;

-

-    default:

-      ASSERT (FALSE);

-  }

-

-  return PciIo->Io.Write (

-                     PciIo,

-                     Width,

-                     PCI_BAR_IDX0,

-                     FieldOffset,

-                     Count,

-                     &Value

-                     );

-}

-

-

-/**

-

-  Read a word from Region 0 of the device specified by PciIo.

-

-  Region 0 must be an iomem region. This is an internal function for the

-  VIRTIO_CFG_READ() macro below.

-

-  @param[in] PciIo        Source PCI device.

-

-  @param[in] FieldOffset  Source offset.

-

-  @param[in] FieldSize    Source field size, must be in { 1, 2, 4, 8 }.

-

-  @param[in] BufferSize   Number of bytes available in the target buffer. Must

-                          equal FieldSize.

-

-  @param[out] Buffer      Target buffer.

-

-

-  @return  Status code returned by PciIo->Io.Read().

-

-**/

-STATIC

-EFIAPI

-EFI_STATUS

-VirtioRead (

-  IN  EFI_PCI_IO_PROTOCOL *PciIo,

-  IN  UINTN               FieldOffset,

-  IN  UINTN               FieldSize,

-  IN  UINTN               BufferSize,

-  OUT VOID                *Buffer

-  )

-{

-  UINTN                     Count;

-  EFI_PCI_IO_PROTOCOL_WIDTH Width;

-

-  ASSERT (FieldSize == BufferSize);

-

-  Count = 1;

-  switch (FieldSize) {

-    case 1:

-      Width = EfiPciIoWidthUint8;

-      break;

-

-    case 2:

-      Width = EfiPciIoWidthUint16;

-      break;

-

-    case 8:

-      Count = 2;

-      // fall through

-

-    case 4:

-      Width = EfiPciIoWidthUint32;

-      break;

-

-    default:

-      ASSERT (FALSE);

-  }

-

-  return PciIo->Io.Read (

-                     PciIo,

-                     Width,

-                     PCI_BAR_IDX0,

-                     FieldOffset,

-                     Count,

-                     Buffer

-                     );

-}

-

-

-/**

-

   Convenience macros to read and write region 0 IO space elements of the

   virtio-blk PCI device, for configuration purposes.

 

@@ -314,66 +178,6 @@ VerifyReadWriteRequest (
 }

 

 

-/**

-

-  Append a contiguous buffer for transmission / reception via the virtio ring.

-

-  This function implements the following sections from virtio-0.9.5:

-  - 2.4.1.1 Placing Buffers into the Descriptor Table

-  - 2.4.1.2 Updating the Available Ring

-

-  Free space is taken as granted, since this driver supports only synchronous

-  requests and host side status is processed in lock-step with request

-  submission. VirtioBlkInit() verifies the ring size in advance.

-

-  @param[in out] Ring           The virtio ring to append the buffer to, as a

-                                descriptor.

-

-  @param [in] BufferPhysAddr    (Guest pseudo-physical) start address of the

-                                transmit / receive buffer

-

-  @param [in] BufferSize        Number of bytes to transmit or receive.

-

-  @param [in] Flags             A bitmask of VRING_DESC_F_* flags. The caller

-                                computes this mask dependent on further buffers

-                                to append and transfer direction.

-                                VRING_DESC_F_INDIRECT is unsupported. The

-                                VRING_DESC.Next field is always set, but the

-                                host only interprets it dependent on

-                                VRING_DESC_F_NEXT.

-

-  @param [in] HeadIdx           The index identifying the head buffer (first

-                                buffer appended) belonging to this same

-                                request.

-

-  @param [in out] NextAvailIdx  On input, the index identifying the next

-                                descriptor available to carry the buffer. On

-                                output, incremented by one, modulo 2^16.

-

-**/

-

-STATIC

-VOID

-EFIAPI

-AppendDesc (

-  IN OUT          VRING  *Ring,

-  IN              UINTN  BufferPhysAddr,

-  IN              UINT32 BufferSize,

-  IN              UINT16 Flags,

-  IN              UINT16 HeadIdx,

-  IN OUT          UINT16 *NextAvailIdx

-  )

-{

-  volatile VRING_DESC *Desc;

-

-  Desc        = &Ring->Desc[*NextAvailIdx % Ring->QueueSize];

-  Desc->Addr  = BufferPhysAddr;

-  Desc->Len   = BufferSize;

-  Desc->Flags = Flags;

-  Ring->Avail.Ring[(*NextAvailIdx)++ % Ring->QueueSize] =

-    HeadIdx % Ring->QueueSize;

-  Desc->Next  = *NextAvailIdx % Ring->QueueSize;

-}

 

 

 /**

@@ -827,128 +631,6 @@ VirtioBlkDriverBindingSupported (
 

 /**

 

-  Configure a virtio ring.

-

-  This function sets up internal storage (the guest-host communication area)

-  and lays out several "navigation" (ie. no-ownership) pointers to parts of

-  that storage.

-

-  Relevant sections from the virtio-0.9.5 spec:

-  - 1.1 Virtqueues,

-  - 2.3 Virtqueue Configuration.

-

-  @param[in]                    The number of descriptors to allocate for the

-                                virtio ring, as requested by the host.

-

-  @param[out] Ring              The virtio ring to set up.

-

-  @retval EFI_OUT_OF_RESOURCES  AllocatePages() failed to allocate contiguous

-                                pages for the requested QueueSize. Fields of

-                                Ring have indeterminate value.

-

-  @retval EFI_SUCCESS           Allocation and setup successful. Ring->Base

-                                (and nothing else) is responsible for

-                                deallocation.

-

-**/

-

-STATIC

-EFI_STATUS

-EFIAPI

-VirtioRingInit (

-  IN  UINT16 QueueSize,

-  OUT VRING  *Ring

-  )

-{

-  UINTN          RingSize;

-  volatile UINT8 *RingPagesPtr;

-

-  RingSize = ALIGN_VALUE (

-               sizeof *Ring->Desc            * QueueSize +

-               sizeof *Ring->Avail.Flags                 +

-               sizeof *Ring->Avail.Idx                   +

-               sizeof *Ring->Avail.Ring      * QueueSize +

-               sizeof *Ring->Avail.UsedEvent,

-               EFI_PAGE_SIZE);

-

-  RingSize += ALIGN_VALUE (

-                sizeof *Ring->Used.Flags                  +

-                sizeof *Ring->Used.Idx                    +

-                sizeof *Ring->Used.UsedElem   * QueueSize +

-                sizeof *Ring->Used.AvailEvent,

-                EFI_PAGE_SIZE);

-

-  Ring->NumPages = EFI_SIZE_TO_PAGES (RingSize);

-  Ring->Base = AllocatePages (Ring->NumPages);

-  if (Ring->Base == NULL) {

-    return EFI_OUT_OF_RESOURCES;

-  }

-  SetMem (Ring->Base, RingSize, 0x00);

-  RingPagesPtr = Ring->Base;

-

-  Ring->Desc = (volatile VOID *) RingPagesPtr;

-  RingPagesPtr += sizeof *Ring->Desc * QueueSize;

-

-  Ring->Avail.Flags = (volatile VOID *) RingPagesPtr;

-  RingPagesPtr += sizeof *Ring->Avail.Flags;

-

-  Ring->Avail.Idx = (volatile VOID *) RingPagesPtr;

-  RingPagesPtr += sizeof *Ring->Avail.Idx;

-

-  Ring->Avail.Ring = (volatile VOID *) RingPagesPtr;

-  RingPagesPtr += sizeof *Ring->Avail.Ring * QueueSize;

-

-  Ring->Avail.UsedEvent = (volatile VOID *) RingPagesPtr;

-  RingPagesPtr += sizeof *Ring->Avail.UsedEvent;

-

-  RingPagesPtr = (volatile UINT8 *) Ring->Base +

-                 ALIGN_VALUE (RingPagesPtr - (volatile UINT8 *) Ring->Base,

-                   EFI_PAGE_SIZE);

-

-  Ring->Used.Flags = (volatile VOID *) RingPagesPtr;

-  RingPagesPtr += sizeof *Ring->Used.Flags;

-

-  Ring->Used.Idx = (volatile VOID *) RingPagesPtr;

-  RingPagesPtr += sizeof *Ring->Used.Idx;

-

-  Ring->Used.UsedElem = (volatile VOID *) RingPagesPtr;

-  RingPagesPtr += sizeof *Ring->Used.UsedElem * QueueSize;

-

-  Ring->Used.AvailEvent = (volatile VOID *) RingPagesPtr;

-  RingPagesPtr += sizeof *Ring->Used.AvailEvent;

-

-  Ring->QueueSize = QueueSize;

-  return EFI_SUCCESS;

-}

-

-

-/**

-

-  Tear down the internal resources of a configured virtio ring.

-

-  The caller is responsible to stop the host from using this ring before

-  invoking this function: the VSTAT_DRIVER_OK bit must be clear in

-  VhdrDeviceStatus.

-

-  @param[out] Ring  The virtio ring to clean up.

-

-**/

-

-

-STATIC

-VOID

-EFIAPI

-VirtioRingUninit (

-  IN OUT VRING *Ring

-  )

-{

-  FreePages (Ring->Base, Ring->NumPages);

-  SetMem (Ring, sizeof *Ring, 0x00);

-}

-

-

-/**

-

   Set up all BlockIo and virtio-blk aspects of this driver for the specified

   device.

 

diff --git a/OvmfPkg/VirtioBlkDxe/VirtioBlk.inf b/OvmfPkg/VirtioBlkDxe/VirtioBlk.inf
index 730903d55e..6dffc3a22a 100644
--- a/OvmfPkg/VirtioBlkDxe/VirtioBlk.inf
+++ b/OvmfPkg/VirtioBlkDxe/VirtioBlk.inf
@@ -35,6 +35,7 @@
   UefiBootServicesTableLib

   UefiDriverEntryPoint

   UefiLib

+  VirtioLib

 

 [Protocols]

   gEfiBlockIoProtocolGuid  ## BY_START