OvmfPkg/VirtioMmioDeviceLib: Implement VIRTIO_DEVICE_PROTOCOL for VirtIo Devices...

[mirror_edk2.git] / OvmfPkg / VirtioBlkDxe / VirtioBlk.c

diff --git a/OvmfPkg/VirtioBlkDxe/VirtioBlk.c b/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
index 01a562d1655e1d9a5525cef83fef8d0c31ae9dff..17b9f71d63beadcb434ea4bda2a0bf632a5e729f 100644 (file)
--- a/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
+++ b/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
@@ -11,6 +11,7 @@
     synchronous requests and EFI_BLOCK_IO_PROTOCOL for now.\r
 \r
   Copyright (C) 2012, Red Hat, Inc.\r
     synchronous requests and EFI_BLOCK_IO_PROTOCOL for now.\r
 \r
   Copyright (C) 2012, Red Hat, Inc.\r

+  Copyright (c) 2012, Intel Corporation. All rights reserved.<BR>\r

 \r
   This program and the accompanying materials are licensed and made available\r
   under the terms and conditions of the BSD License which accompanies this\r
 \r
   This program and the accompanying materials are licensed and made available\r
   under the terms and conditions of the BSD License which accompanies this\r


@@ -23,151 +24,16 @@
 **/\r
 \r
 #include <IndustryStandard/Pci.h>\r
 **/\r
 \r
 #include <IndustryStandard/Pci.h>\r

+#include <IndustryStandard/VirtioBlk.h>\r

 #include <Library/BaseMemoryLib.h>\r
 #include <Library/DebugLib.h>\r
 #include <Library/MemoryAllocationLib.h>\r
 #include <Library/UefiBootServicesTableLib.h>\r
 #include <Library/UefiLib.h>\r
 #include <Library/BaseMemoryLib.h>\r
 #include <Library/DebugLib.h>\r
 #include <Library/MemoryAllocationLib.h>\r
 #include <Library/UefiBootServicesTableLib.h>\r
 #include <Library/UefiLib.h>\r

+#include <Library/VirtioLib.h>\r

 \r
 #include "VirtioBlk.h"\r
 \r
 \r
 #include "VirtioBlk.h"\r
 \r

-/**\r
-\r
-  Write a word into Region 0 of the device specified by PciIo.\r
-\r
-  Region 0 must be an iomem region. This is an internal function for the\r
-  VIRTIO_CFG_WRITE() macro below.\r
-\r
-  @param[in] PciIo        Target PCI device.\r
-\r
-  @param[in] FieldOffset  Destination offset.\r
-\r
-  @param[in] FieldSize    Destination field size, must be in { 1, 2, 4, 8 }.\r
-\r
-  @param[in] Value        Little endian value to write, converted to UINT64.\r
-                          The least significant FieldSize bytes will be used.\r
-\r
-\r
-  @return  Status code returned by PciIo->Io.Write().\r
-\r
-**/\r
-STATIC\r
-EFIAPI\r
-EFI_STATUS\r
-VirtioWrite (\r
-  IN EFI_PCI_IO_PROTOCOL *PciIo,\r
-  IN UINTN               FieldOffset,\r
-  IN UINTN               FieldSize,\r
-  IN UINT64              Value\r
-  )\r
-{\r
-  UINTN                     Count;\r
-  EFI_PCI_IO_PROTOCOL_WIDTH Width;\r
-\r
-  Count = 1;\r
-  switch (FieldSize) {\r
-    case 1:\r
-      Width = EfiPciIoWidthUint8;\r
-      break;\r
-\r
-    case 2:\r
-      Width = EfiPciIoWidthUint16;\r
-      break;\r
-\r
-    case 8:\r
-      Count = 2;\r
-      // fall through\r
-\r
-    case 4:\r
-      Width = EfiPciIoWidthUint32;\r
-      break;\r
-\r
-    default:\r
-      ASSERT (FALSE);\r
-  }\r
-\r
-  return PciIo->Io.Write (\r
-                     PciIo,\r
-                     Width,\r
-                     PCI_BAR_IDX0,\r
-                     FieldOffset,\r
-                     Count,\r
-                     &Value\r
-                     );\r
-}\r
-\r
-\r
-/**\r
-\r
-  Read a word from Region 0 of the device specified by PciIo.\r
-\r
-  Region 0 must be an iomem region. This is an internal function for the\r
-  VIRTIO_CFG_READ() macro below.\r
-\r
-  @param[in] PciIo        Source PCI device.\r
-\r
-  @param[in] FieldOffset  Source offset.\r
-\r
-  @param[in] FieldSize    Source field size, must be in { 1, 2, 4, 8 }.\r
-\r
-  @param[in] BufferSize   Number of bytes available in the target buffer. Must\r
-                          equal FieldSize.\r
-\r
-  @param[out] Buffer      Target buffer.\r
-\r
-\r
-  @return  Status code returned by PciIo->Io.Read().\r
-\r
-**/\r
-STATIC\r
-EFIAPI\r
-EFI_STATUS\r
-VirtioRead (\r
-  IN  EFI_PCI_IO_PROTOCOL *PciIo,\r
-  IN  UINTN               FieldOffset,\r
-  IN  UINTN               FieldSize,\r
-  IN  UINTN               BufferSize,\r
-  OUT VOID                *Buffer\r
-  )\r
-{\r
-  UINTN                     Count;\r
-  EFI_PCI_IO_PROTOCOL_WIDTH Width;\r
-\r
-  ASSERT (FieldSize == BufferSize);\r
-\r
-  Count = 1;\r
-  switch (FieldSize) {\r
-    case 1:\r
-      Width = EfiPciIoWidthUint8;\r
-      break;\r
-\r
-    case 2:\r
-      Width = EfiPciIoWidthUint16;\r
-      break;\r
-\r
-    case 8:\r
-      Count = 2;\r
-      // fall through\r
-\r
-    case 4:\r
-      Width = EfiPciIoWidthUint32;\r
-      break;\r
-\r
-    default:\r
-      ASSERT (FALSE);\r
-  }\r
-\r
-  return PciIo->Io.Read (\r
-                     PciIo,\r
-                     Width,\r
-                     PCI_BAR_IDX0,\r
-                     FieldOffset,\r
-                     Count,\r
-                     Buffer\r
-                     );\r
-}\r
-\r
-\r

 /**\r
 \r
   Convenience macros to read and write region 0 IO space elements of the\r
 /**\r
 \r
   Convenience macros to read and write region 0 IO space elements of the\r


@@ -313,66 +179,6 @@ VerifyReadWriteRequest (
 }\r
 \r
 \r
 }\r
 \r
 \r

-/**\r
-\r
-  Append a contiguous buffer for transmission / reception via the virtio ring.\r
-\r
-  This function implements the following sections from virtio-0.9.5:\r
-  - 2.4.1.1 Placing Buffers into the Descriptor Table\r
-  - 2.4.1.2 Updating the Available Ring\r
-\r
-  Free space is taken as granted, since this driver supports only synchronous\r
-  requests and host side status is processed in lock-step with request\r
-  submission. VirtioBlkInit() verifies the ring size in advance.\r
-\r
-  @param[in out] Ring           The virtio ring to append the buffer to, as a\r
-                                descriptor.\r
-\r
-  @param [in] BufferPhysAddr    (Guest pseudo-physical) start address of the\r
-                                transmit / receive buffer\r
-\r
-  @param [in] BufferSize        Number of bytes to transmit or receive.\r
-\r
-  @param [in] Flags             A bitmask of VRING_DESC_F_* flags. The caller\r
-                                computes this mask dependent on further buffers\r
-                                to append and transfer direction.\r
-                                VRING_DESC_F_INDIRECT is unsupported. The\r
-                                VRING_DESC.Next field is always set, but the\r
-                                host only interprets it dependent on\r
-                                VRING_DESC_F_NEXT.\r
-\r
-  @param [in] HeadIdx           The index identifying the head buffer (first\r
-                                buffer appended) belonging to this same\r
-                                request.\r
-\r
-  @param [in out] NextAvailIdx  On input, the index identifying the next\r
-                                descriptor available to carry the buffer. On\r
-                                output, incremented by one, modulo 2^16.\r
-\r
-**/\r
-\r
-STATIC\r
-VOID\r
-EFIAPI\r
-AppendDesc (\r
-  IN OUT          VRING  *Ring,\r
-  IN              UINTN  BufferPhysAddr,\r
-  IN              UINT32 BufferSize,\r
-  IN              UINT16 Flags,\r
-  IN              UINT16 HeadIdx,\r
-  IN OUT          UINT16 *NextAvailIdx\r
-  )\r
-{\r
-  volatile VRING_DESC *Desc;\r
-\r
-  Desc        = &Ring->Desc[*NextAvailIdx % Ring->QueueSize];\r
-  Desc->Addr  = BufferPhysAddr;\r
-  Desc->Len   = BufferSize;\r
-  Desc->Flags = Flags;\r
-  Ring->Avail.Ring[(*NextAvailIdx)++ % Ring->QueueSize] =\r
-    HeadIdx % Ring->QueueSize;\r
-  Desc->Next  = *NextAvailIdx % Ring->QueueSize;\r
-}\r

 \r
 \r
 /**\r
 \r
 \r
 /**\r


@@ -443,9 +249,7 @@ SynchronousRequest (
   UINT32                  BlockSize;\r
   volatile VIRTIO_BLK_REQ Request;\r
   volatile UINT8          HostStatus;\r
   UINT32                  BlockSize;\r
   volatile VIRTIO_BLK_REQ Request;\r
   volatile UINT8          HostStatus;\r

-  UINT16                  FirstAvailIdx;\r
-  UINT16                  NextAvailIdx;\r
-  UINTN                   PollPeriodUsecs;\r
+  DESC_INDICES            Indices;\r

 \r
   BlockSize = Dev->BlockIoMedia.BlockSize;\r
 \r
 \r
   BlockSize = Dev->BlockIoMedia.BlockSize;\r
 \r


@@ -468,13 +272,9 @@ SynchronousRequest (
                    (BufferSize == 0 ? VIRTIO_BLK_T_FLUSH : VIRTIO_BLK_T_OUT) :\r
                    VIRTIO_BLK_T_IN;\r
   Request.IoPrio = 0;\r
                    (BufferSize == 0 ? VIRTIO_BLK_T_FLUSH : VIRTIO_BLK_T_OUT) :\r
                    VIRTIO_BLK_T_IN;\r
   Request.IoPrio = 0;\r

-  Request.Sector = Lba * (BlockSize / 512);\r
+  Request.Sector = MultU64x32(Lba, BlockSize / 512);\r

 \r
 \r

-  //\r
-  // Prepare for virtio-0.9.5, 2.4.2 Receiving Used Buffers From the Device.\r
-  // We're going to poll the answer, the host should not send an interrupt.\r
-  //\r
-  *Dev->Ring.Avail.Flags = (UINT16) VRING_AVAIL_F_NO_INTERRUPT;\r
+  VirtioPrepare (&Dev->Ring, &Indices);\r

 \r
   //\r
   // preset a host status for ourselves that we do not accept as success\r
 \r
   //\r
   // preset a host status for ourselves that we do not accept as success\r


@@ -487,17 +287,11 @@ SynchronousRequest (
   //\r
   ASSERT (Dev->Ring.QueueSize >= 3);\r
 \r
   //\r
   ASSERT (Dev->Ring.QueueSize >= 3);\r
 \r

-  //\r
-  // Implement virtio-0.9.5, 2.4.1 Supplying Buffers to the Device.\r
-  //\r
-  FirstAvailIdx = *Dev->Ring.Avail.Idx;\r
-  NextAvailIdx  = FirstAvailIdx;\r
-\r

   //\r
   // virtio-blk header in first desc\r
   //\r
   //\r
   // virtio-blk header in first desc\r
   //\r

-  AppendDesc (&Dev->Ring, (UINTN) &Request, sizeof Request, VRING_DESC_F_NEXT,\r
-    FirstAvailIdx, &NextAvailIdx);\r
+  VirtioAppendDesc (&Dev->Ring, (UINTN) &Request, sizeof Request,\r
+    VRING_DESC_F_NEXT, &Indices);\r

 \r
   //\r
   // data buffer for read/write in second desc\r
 \r
   //\r
   // data buffer for read/write in second desc\r


@@ -516,52 +310,22 @@ SynchronousRequest (
     //\r
     // VRING_DESC_F_WRITE is interpreted from the host's point of view.\r
     //\r
     //\r
     // VRING_DESC_F_WRITE is interpreted from the host's point of view.\r
     //\r

-    AppendDesc (&Dev->Ring, (UINTN) Buffer, (UINT32) BufferSize,\r
+    VirtioAppendDesc (&Dev->Ring, (UINTN) Buffer, (UINT32) BufferSize,\r

       VRING_DESC_F_NEXT | (RequestIsWrite ? 0 : VRING_DESC_F_WRITE),\r
       VRING_DESC_F_NEXT | (RequestIsWrite ? 0 : VRING_DESC_F_WRITE),\r

-      FirstAvailIdx, &NextAvailIdx);\r
+      &Indices);\r

   }\r
 \r
   //\r
   // host status in last (second or third) desc\r
   //\r
   }\r
 \r
   //\r
   // host status in last (second or third) desc\r
   //\r

-  AppendDesc (&Dev->Ring, (UINTN) &HostStatus, sizeof HostStatus,\r
-    VRING_DESC_F_WRITE, FirstAvailIdx, &NextAvailIdx);\r
+  VirtioAppendDesc (&Dev->Ring, (UINTN) &HostStatus, sizeof HostStatus,\r
+    VRING_DESC_F_WRITE, &Indices);\r

 \r
   //\r
 \r
   //\r

-  // virtio-0.9.5, 2.4.1.3 Updating the Index Field\r
+  // virtio-blk's only virtqueue is #0, called "requestq" (see Appendix D).\r

   //\r
   //\r

-  MemoryFence();\r
-  *Dev->Ring.Avail.Idx = NextAvailIdx;\r
-\r
-  //\r
-  // virtio-0.9.5, 2.4.1.4 Notifying the Device -- gratuitous notifications are\r
-  // OK. virtio-blk's only virtqueue is #0, called "requestq" (see Appendix D).\r
-  //\r
-  MemoryFence();\r
-  if (EFI_ERROR (VIRTIO_CFG_WRITE (Dev, Generic.VhdrQueueNotify, 0))) {\r
-    return EFI_DEVICE_ERROR;\r
-  }\r
-\r
-  //\r
-  // virtio-0.9.5, 2.4.2 Receiving Used Buffers From the Device\r
-  // Wait until the host processes and acknowledges our 3-part descriptor\r
-  // chain. The condition we use for polling is greatly simplified and relies\r
-  // on synchronous, the lock-step progress.\r
-  //\r
-  // Keep slowing down until we reach a poll period of slightly above 1 ms.\r
-  //\r
-  PollPeriodUsecs = 1;\r
-  MemoryFence();\r
-  while (*Dev->Ring.Used.Idx != NextAvailIdx) {\r
-    gBS->Stall (PollPeriodUsecs); // calls AcpiTimerLib::MicroSecondDelay\r
-\r
-    if (PollPeriodUsecs < 1024) {\r
-      PollPeriodUsecs *= 2;\r
-    }\r
-    MemoryFence();\r
-  }\r
-\r
-  if (HostStatus == VIRTIO_BLK_S_OK) {\r
+  if (VirtioFlush (Dev->PciIo, 0, &Dev->Ring, &Indices) == EFI_SUCCESS &&\r
+      HostStatus == VIRTIO_BLK_S_OK) {\r

     return EFI_SUCCESS;\r
   }\r
 \r
     return EFI_SUCCESS;\r
   }\r
 \r


@@ -811,7 +575,7 @@ VirtioBlkDriverBindingSupported (
     Status = (Pci.Hdr.VendorId == 0x1AF4 &&\r
               Pci.Hdr.DeviceId >= 0x1000 && Pci.Hdr.DeviceId <= 0x103F &&\r
               Pci.Hdr.RevisionID == 0x00 &&\r
     Status = (Pci.Hdr.VendorId == 0x1AF4 &&\r
               Pci.Hdr.DeviceId >= 0x1000 && Pci.Hdr.DeviceId <= 0x103F &&\r
               Pci.Hdr.RevisionID == 0x00 &&\r

-              Pci.Device.SubsystemID == 0x02) ? EFI_SUCCESS : EFI_UNSUPPORTED;\r
+              Pci.Device.SubsystemID == VIRTIO_SUBSYSTEM_BLOCK_DEVICE) ? EFI_SUCCESS : EFI_UNSUPPORTED;\r

   }\r
 \r
   //\r
   }\r
 \r
   //\r


@@ -824,128 +588,6 @@ VirtioBlkDriverBindingSupported (
 }\r
 \r
 \r
 }\r
 \r
 \r

-/**\r
-\r
-  Configure a virtio ring.\r
-\r
-  This function sets up internal storage (the guest-host communication area)\r
-  and lays out several "navigation" (ie. no-ownership) pointers to parts of\r
-  that storage.\r
-\r
-  Relevant sections from the virtio-0.9.5 spec:\r
-  - 1.1 Virtqueues,\r
-  - 2.3 Virtqueue Configuration.\r
-\r
-  @param[in]                    The number of descriptors to allocate for the\r
-                                virtio ring, as requested by the host.\r
-\r
-  @param[out] Ring              The virtio ring to set up.\r
-\r
-  @retval EFI_OUT_OF_RESOURCES  AllocatePages() failed to allocate contiguous\r
-                                pages for the requested QueueSize. Fields of\r
-                                Ring have indeterminate value.\r
-\r
-  @retval EFI_SUCCESS           Allocation and setup successful. Ring->Base\r
-                                (and nothing else) is responsible for\r
-                                deallocation.\r
-\r
-**/\r
-\r
-STATIC\r
-EFI_STATUS\r
-EFIAPI\r
-VirtioRingInit (\r
-  IN  UINT16 QueueSize,\r
-  OUT VRING  *Ring\r
-  )\r
-{\r
-  UINTN          RingSize;\r
-  volatile UINT8 *RingPagesPtr;\r
-\r
-  RingSize = ALIGN_VALUE (\r
-               sizeof *Ring->Desc            * QueueSize +\r
-               sizeof *Ring->Avail.Flags                 +\r
-               sizeof *Ring->Avail.Idx                   +\r
-               sizeof *Ring->Avail.Ring      * QueueSize +\r
-               sizeof *Ring->Avail.UsedEvent,\r
-               EFI_PAGE_SIZE);\r
-\r
-  RingSize += ALIGN_VALUE (\r
-                sizeof *Ring->Used.Flags                  +\r
-                sizeof *Ring->Used.Idx                    +\r
-                sizeof *Ring->Used.UsedElem   * QueueSize +\r
-                sizeof *Ring->Used.AvailEvent,\r
-                EFI_PAGE_SIZE);\r
-\r
-  Ring->NumPages = EFI_SIZE_TO_PAGES (RingSize);\r
-  Ring->Base = AllocatePages (Ring->NumPages);\r
-  if (Ring->Base == NULL) {\r
-    return EFI_OUT_OF_RESOURCES;\r
-  }\r
-  SetMem (Ring->Base, RingSize, 0x00);\r
-  RingPagesPtr = Ring->Base;\r
-\r
-  Ring->Desc = (volatile VOID *) RingPagesPtr;\r
-  RingPagesPtr += sizeof *Ring->Desc * QueueSize;\r
-\r
-  Ring->Avail.Flags = (volatile VOID *) RingPagesPtr;\r
-  RingPagesPtr += sizeof *Ring->Avail.Flags;\r
-\r
-  Ring->Avail.Idx = (volatile VOID *) RingPagesPtr;\r
-  RingPagesPtr += sizeof *Ring->Avail.Idx;\r
-\r
-  Ring->Avail.Ring = (volatile VOID *) RingPagesPtr;\r
-  RingPagesPtr += sizeof *Ring->Avail.Ring * QueueSize;\r
-\r
-  Ring->Avail.UsedEvent = (volatile VOID *) RingPagesPtr;\r
-  RingPagesPtr += sizeof *Ring->Avail.UsedEvent;\r
-\r
-  RingPagesPtr = (volatile UINT8 *) Ring->Base +\r
-                 ALIGN_VALUE (RingPagesPtr - (volatile UINT8 *) Ring->Base,\r
-                   EFI_PAGE_SIZE);\r
-\r
-  Ring->Used.Flags = (volatile VOID *) RingPagesPtr;\r
-  RingPagesPtr += sizeof *Ring->Used.Flags;\r
-\r
-  Ring->Used.Idx = (volatile VOID *) RingPagesPtr;\r
-  RingPagesPtr += sizeof *Ring->Used.Idx;\r
-\r
-  Ring->Used.UsedElem = (volatile VOID *) RingPagesPtr;\r
-  RingPagesPtr += sizeof *Ring->Used.UsedElem * QueueSize;\r
-\r
-  Ring->Used.AvailEvent = (volatile VOID *) RingPagesPtr;\r
-  RingPagesPtr += sizeof *Ring->Used.AvailEvent;\r
-\r
-  Ring->QueueSize = QueueSize;\r
-  return EFI_SUCCESS;\r
-}\r
-\r
-\r
-/**\r
-\r
-  Tear down the internal resources of a configured virtio ring.\r
-\r
-  The caller is responsible to stop the host from using this ring before\r
-  invoking this function: the VSTAT_DRIVER_OK bit must be clear in\r
-  VhdrDeviceStatus.\r
-\r
-  @param[out] Ring  The virtio ring to clean up.\r
-\r
-**/\r
-\r
-\r
-STATIC\r
-VOID\r
-EFIAPI\r
-VirtioRingUninit (\r
-  IN OUT VRING *Ring\r
-  )\r
-{\r
-  FreePages (Ring->Base, Ring->NumPages);\r
-  SetMem (Ring, sizeof *Ring, 0x00);\r
-}\r
-\r
-\r

 /**\r
 \r
   Set up all BlockIo and virtio-blk aspects of this driver for the specified\r
 /**\r
 \r
   Set up all BlockIo and virtio-blk aspects of this driver for the specified\r


@@ -1023,7 +665,7 @@ VirtioBlkInit (
       goto Failed;\r
     }\r
     if (BlockSize == 0 || BlockSize % 512 != 0 ||\r
       goto Failed;\r
     }\r
     if (BlockSize == 0 || BlockSize % 512 != 0 ||\r

-        NumSectors % (BlockSize / 512) != 0) {\r
+        ModU64x32 (NumSectors, BlockSize / 512) != 0) {\r

       //\r
       // We can only handle a logical block consisting of whole sectors,\r
       // and only a disk composed of whole logical blocks.\r
       //\r
       // We can only handle a logical block consisting of whole sectors,\r
       // and only a disk composed of whole logical blocks.\r


@@ -1106,7 +748,8 @@ VirtioBlkInit (
   Dev->BlockIoMedia.WriteCaching     = !!(Features & VIRTIO_BLK_F_FLUSH);\r
   Dev->BlockIoMedia.BlockSize        = BlockSize;\r
   Dev->BlockIoMedia.IoAlign          = 0;\r
   Dev->BlockIoMedia.WriteCaching     = !!(Features & VIRTIO_BLK_F_FLUSH);\r
   Dev->BlockIoMedia.BlockSize        = BlockSize;\r
   Dev->BlockIoMedia.IoAlign          = 0;\r

-  Dev->BlockIoMedia.LastBlock        = NumSectors / (BlockSize / 512) - 1;\r
+  Dev->BlockIoMedia.LastBlock        = DivU64x32 (NumSectors,\r
+                                         BlockSize / 512) - 1;\r

   return EFI_SUCCESS;\r
 \r
 ReleaseQueue:\r
   return EFI_SUCCESS;\r
 \r
 ReleaseQueue:\r


@@ -1301,18 +944,32 @@ VirtioBlkDriverBindingStop (
   IN EFI_HANDLE                  *ChildHandleBuffer\r
   )\r
 {\r
   IN EFI_HANDLE                  *ChildHandleBuffer\r
   )\r
 {\r

-  VBLK_DEV   *Dev;\r
-  EFI_STATUS Status;\r
+  EFI_STATUS            Status;\r
+  EFI_BLOCK_IO_PROTOCOL *BlockIo;\r
+  VBLK_DEV              *Dev;\r

 \r
 \r

-  Dev = VIRTIO_BLK_FROM_BLOCK_IO (This);\r
+  Status = gBS->OpenProtocol (\r
+                  DeviceHandle,                  // candidate device\r
+                  &gEfiBlockIoProtocolGuid,      // retrieve the BlockIo iface\r
+                  (VOID **)&BlockIo,             // target pointer\r
+                  This->DriverBindingHandle,     // requestor driver identity\r
+                  DeviceHandle,                  // requesting lookup for dev.\r
+                  EFI_OPEN_PROTOCOL_GET_PROTOCOL // lookup only, no ref. added\r
+                  );\r
+  if (EFI_ERROR (Status)) {\r
+    return Status;\r
+  }\r
+\r
+  Dev = VIRTIO_BLK_FROM_BLOCK_IO (BlockIo);\r

 \r
   //\r
 \r
   //\r

-  // If DriverBindingStop() is called with the driver instance still in use,\r
-  // or any of the parameters are invalid, we've caught a bug.\r
+  // Handle Stop() requests for in-use driver instances gracefully.\r

   //\r
   Status = gBS->UninstallProtocolInterface (DeviceHandle,\r
                   &gEfiBlockIoProtocolGuid, &Dev->BlockIo);\r
   //\r
   Status = gBS->UninstallProtocolInterface (DeviceHandle,\r
                   &gEfiBlockIoProtocolGuid, &Dev->BlockIo);\r

-  ASSERT (Status == EFI_SUCCESS);\r
+  if (EFI_ERROR (Status)) {\r
+    return Status;\r
+  }\r

 \r
   VirtioBlkUninit (Dev);\r
 \r
 \r
   VirtioBlkUninit (Dev);\r
 \r


@@ -1356,13 +1013,13 @@ STATIC EFI_DRIVER_BINDING_PROTOCOL gDriverBinding = {
 // for unambiguous identification.\r
 //\r
 \r
 // for unambiguous identification.\r
 //\r
 \r

-STATIC GLOBAL_REMOVE_IF_UNREFERENCED\r
+STATIC\r

 EFI_UNICODE_STRING_TABLE mDriverNameTable[] = {\r
   { "eng;en", L"Virtio Block Driver" },\r
   { NULL,     NULL                   }\r
 };\r
 \r
 EFI_UNICODE_STRING_TABLE mDriverNameTable[] = {\r
   { "eng;en", L"Virtio Block Driver" },\r
   { NULL,     NULL                   }\r
 };\r
 \r

-STATIC GLOBAL_REMOVE_IF_UNREFERENCED\r
+STATIC\r

 EFI_COMPONENT_NAME_PROTOCOL gComponentName;\r
 \r
 EFI_STATUS\r
 EFI_COMPONENT_NAME_PROTOCOL gComponentName;\r
 \r
 EFI_STATUS\r


@@ -1395,14 +1052,14 @@ VirtioBlkGetDeviceName (
   return EFI_UNSUPPORTED;\r
 }\r
 \r
   return EFI_UNSUPPORTED;\r
 }\r
 \r

-STATIC GLOBAL_REMOVE_IF_UNREFERENCED\r
+STATIC\r

 EFI_COMPONENT_NAME_PROTOCOL gComponentName = {\r
   &VirtioBlkGetDriverName,\r
   &VirtioBlkGetDeviceName,\r
   "eng" // SupportedLanguages, ISO 639-2 language codes\r
 };\r
 \r
 EFI_COMPONENT_NAME_PROTOCOL gComponentName = {\r
   &VirtioBlkGetDriverName,\r
   &VirtioBlkGetDeviceName,\r
   "eng" // SupportedLanguages, ISO 639-2 language codes\r
 };\r
 \r

-STATIC GLOBAL_REMOVE_IF_UNREFERENCED\r
+STATIC\r

 EFI_COMPONENT_NAME2_PROTOCOL gComponentName2 = {\r
   (EFI_COMPONENT_NAME2_GET_DRIVER_NAME)     &VirtioBlkGetDriverName,\r
   (EFI_COMPONENT_NAME2_GET_CONTROLLER_NAME) &VirtioBlkGetDeviceName,\r
 EFI_COMPONENT_NAME2_PROTOCOL gComponentName2 = {\r
   (EFI_COMPONENT_NAME2_GET_DRIVER_NAME)     &VirtioBlkGetDriverName,\r
   (EFI_COMPONENT_NAME2_GET_CONTROLLER_NAME) &VirtioBlkGetDeviceName,\r