3 This driver produces Block I/O Protocol instances for virtio-blk devices.
5 The implementation is basic:
7 - No attach/detach (ie. removable media).
9 - Although the non-blocking interfaces of EFI_BLOCK_IO2_PROTOCOL could be a
10 good match for multiple in-flight virtio-blk requests, we stick to
11 synchronous requests and EFI_BLOCK_IO_PROTOCOL for now.
13 Copyright (C) 2012, Red Hat, Inc.
14 Copyright (c) 2012 - 2016, Intel Corporation. All rights reserved.<BR>
15 Copyright (c) 2017, AMD Inc, All rights reserved.<BR>
17 This program and the accompanying materials are licensed and made available
18 under the terms and conditions of the BSD License which accompanies this
19 distribution. The full text of the license may be found at
20 http://opensource.org/licenses/bsd-license.php
22 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT
23 WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
27 #include <IndustryStandard/VirtioBlk.h>
28 #include <Library/BaseMemoryLib.h>
29 #include <Library/DebugLib.h>
30 #include <Library/MemoryAllocationLib.h>
31 #include <Library/UefiBootServicesTableLib.h>
32 #include <Library/UefiLib.h>
33 #include <Library/VirtioLib.h>
35 #include "VirtioBlk.h"
39 Convenience macros to read and write region 0 IO space elements of the
40 virtio-blk device, for configuration purposes.
42 The following macros make it possible to specify only the "core parameters"
43 for such accesses and to derive the rest. By the time VIRTIO_CFG_WRITE()
44 returns, the transaction will have been completed.
46 @param[in] Dev Pointer to the VBLK_DEV structure whose VirtIo space
47 we're accessing. Dev->VirtIo must be valid.
49 @param[in] Field A field name from VBLK_HDR, identifying the virtio-blk
50 configuration item to access.
52 @param[in] Value (VIRTIO_CFG_WRITE() only.) The value to write to the
53 selected configuration item.
55 @param[out] Pointer (VIRTIO_CFG_READ() only.) The object to receive the
56 value read from the configuration item. Its type must be
57 one of UINT8, UINT16, UINT32, UINT64.
60 @return Status code returned by Virtio->WriteDevice() /
65 #define VIRTIO_CFG_WRITE(Dev, Field, Value) ((Dev)->VirtIo->WriteDevice ( \
67 OFFSET_OF_VBLK (Field), \
68 SIZE_OF_VBLK (Field), \
72 #define VIRTIO_CFG_READ(Dev, Field, Pointer) ((Dev)->VirtIo->ReadDevice ( \
74 OFFSET_OF_VBLK (Field), \
75 SIZE_OF_VBLK (Field), \
82 // UEFI Spec 2.3.1 + Errata C, 12.8 EFI Block I/O Protocol
83 // Driver Writer's Guide for UEFI 2.3.1 v1.01,
84 // 24.2 Block I/O Protocol Implementations
89 IN EFI_BLOCK_IO_PROTOCOL
*This
,
90 IN BOOLEAN ExtendedVerification
94 // If we managed to initialize and install the driver, then the device is
102 Verify correctness of the read/write (not flush) request submitted to the
103 EFI_BLOCK_IO_PROTOCOL instance.
105 This function provides most verification steps described in:
107 UEFI Spec 2.3.1 + Errata C, 12.8 EFI Block I/O Protocol, 12.8 EFI Block I/O
109 - EFI_BLOCK_IO_PROTOCOL.ReadBlocks()
110 - EFI_BLOCK_IO_PROTOCOL.WriteBlocks()
112 Driver Writer's Guide for UEFI 2.3.1 v1.01,
113 - 24.2.2. ReadBlocks() and ReadBlocksEx() Implementation
114 - 24.2.3 WriteBlocks() and WriteBlockEx() Implementation
116 Request sizes are limited to 1 GB (checked). This is not a practical
117 limitation, just conformance to virtio-0.9.5, 2.3.2 Descriptor Table: "no
118 descriptor chain may be more than 2^32 bytes long in total".
120 Some Media characteristics are hardcoded in VirtioBlkInit() below (like
121 non-removable media, no restriction on buffer alignment etc); we rely on
122 those here without explicit mention.
124 @param[in] Media The EFI_BLOCK_IO_MEDIA characteristics for
125 this driver instance, extracted from the
126 underlying virtio-blk device at initialization
127 time. We validate the request against this set
131 @param[in] Lba Logical Block Address: number of logical
132 blocks to skip from the beginning of the
135 @param[in] PositiveBufferSize Size of buffer to transfer, in bytes. The
136 caller is responsible to ensure this parameter
139 @param[in] RequestIsWrite TRUE iff data transfer goes from guest to
143 @@return Validation result to be forwarded outwards by
144 ReadBlocks() and WriteBlocks, as required by
151 VerifyReadWriteRequest (
152 IN EFI_BLOCK_IO_MEDIA
*Media
,
154 IN UINTN PositiveBufferSize
,
155 IN BOOLEAN RequestIsWrite
160 ASSERT (PositiveBufferSize
> 0);
162 if (PositiveBufferSize
> SIZE_1GB
||
163 PositiveBufferSize
% Media
->BlockSize
> 0) {
164 return EFI_BAD_BUFFER_SIZE
;
166 BlockCount
= PositiveBufferSize
/ Media
->BlockSize
;
169 // Avoid unsigned wraparound on either side in the second comparison.
171 if (Lba
> Media
->LastBlock
|| BlockCount
- 1 > Media
->LastBlock
- Lba
) {
172 return EFI_INVALID_PARAMETER
;
175 if (RequestIsWrite
&& Media
->ReadOnly
) {
176 return EFI_WRITE_PROTECTED
;
187 Format a read / write / flush request as three consecutive virtio
188 descriptors, push them to the host, and poll for the response.
190 This is the main workhorse function. Two use cases are supported, read/write
191 and flush. The function may only be called after the request parameters have
193 - specific checks in ReadBlocks() / WriteBlocks() / FlushBlocks(), and
194 - VerifyReadWriteRequest() (for read/write only).
196 Parameters handled commonly:
198 @param[in] Dev The virtio-blk device the request is targeted
203 @param[in] Lba Must be zero.
205 @param[in] BufferSize Must be zero.
207 @param[in out] Buffer Ignored by the function.
209 @param[in] RequestIsWrite Must be TRUE.
213 @param[in] Lba Logical Block Address: number of logical blocks
214 to skip from the beginning of the device.
216 @param[in] BufferSize Size of buffer to transfer, in bytes. The caller
217 is responsible to ensure this parameter is
220 @param[in out] Buffer The guest side area to read data from the device
221 into, or write data to the device from.
223 @param[in] RequestIsWrite TRUE iff data transfer goes from guest to
226 Return values are common to both use cases, and are appropriate to be
227 forwarded by the EFI_BLOCK_IO_PROTOCOL functions (ReadBlocks(),
228 WriteBlocks(), FlushBlocks()).
231 @retval EFI_SUCCESS Transfer complete.
233 @retval EFI_DEVICE_ERROR Failed to notify host side via VirtIo write, or
234 unable to parse host response, or host response
235 is not VIRTIO_BLK_S_OK.
246 IN OUT
volatile VOID
*Buffer
,
247 IN BOOLEAN RequestIsWrite
251 volatile VIRTIO_BLK_REQ Request
;
252 volatile UINT8 HostStatus
;
253 DESC_INDICES Indices
;
255 BlockSize
= Dev
->BlockIoMedia
.BlockSize
;
258 // ensured by VirtioBlkInit()
260 ASSERT (BlockSize
> 0);
261 ASSERT (BlockSize
% 512 == 0);
264 // ensured by contract above, plus VerifyReadWriteRequest()
266 ASSERT (BufferSize
% BlockSize
== 0);
269 // Prepare virtio-blk request header, setting zero size for flush.
270 // IO Priority is homogeneously 0.
272 Request
.Type
= RequestIsWrite
?
273 (BufferSize
== 0 ? VIRTIO_BLK_T_FLUSH
: VIRTIO_BLK_T_OUT
) :
276 Request
.Sector
= MultU64x32(Lba
, BlockSize
/ 512);
278 VirtioPrepare (&Dev
->Ring
, &Indices
);
281 // preset a host status for ourselves that we do not accept as success
283 HostStatus
= VIRTIO_BLK_S_IOERR
;
286 // ensured by VirtioBlkInit() -- this predicate, in combination with the
287 // lock-step progress, ensures we don't have to track free descriptors.
289 ASSERT (Dev
->Ring
.QueueSize
>= 3);
292 // virtio-blk header in first desc
294 VirtioAppendDesc (&Dev
->Ring
, (UINTN
) &Request
, sizeof Request
,
295 VRING_DESC_F_NEXT
, &Indices
);
298 // data buffer for read/write in second desc
300 if (BufferSize
> 0) {
302 // From virtio-0.9.5, 2.3.2 Descriptor Table:
303 // "no descriptor chain may be more than 2^32 bytes long in total".
305 // The predicate is ensured by the call contract above (for flush), or
306 // VerifyReadWriteRequest() (for read/write). It also implies that
307 // converting BufferSize to UINT32 will not truncate it.
309 ASSERT (BufferSize
<= SIZE_1GB
);
312 // VRING_DESC_F_WRITE is interpreted from the host's point of view.
314 VirtioAppendDesc (&Dev
->Ring
, (UINTN
) Buffer
, (UINT32
) BufferSize
,
315 VRING_DESC_F_NEXT
| (RequestIsWrite
? 0 : VRING_DESC_F_WRITE
),
320 // host status in last (second or third) desc
322 VirtioAppendDesc (&Dev
->Ring
, (UINTN
) &HostStatus
, sizeof HostStatus
,
323 VRING_DESC_F_WRITE
, &Indices
);
326 // virtio-blk's only virtqueue is #0, called "requestq" (see Appendix D).
328 if (VirtioFlush (Dev
->VirtIo
, 0, &Dev
->Ring
, &Indices
,
329 NULL
) == EFI_SUCCESS
&&
330 HostStatus
== VIRTIO_BLK_S_OK
) {
334 return EFI_DEVICE_ERROR
;
340 ReadBlocks() operation for virtio-blk.
343 - UEFI Spec 2.3.1 + Errata C, 12.8 EFI Block I/O Protocol, 12.8 EFI Block I/O
344 Protocol, EFI_BLOCK_IO_PROTOCOL.ReadBlocks().
345 - Driver Writer's Guide for UEFI 2.3.1 v1.01, 24.2.2. ReadBlocks() and
346 ReadBlocksEx() Implementation.
348 Parameter checks and conformant return values are implemented in
349 VerifyReadWriteRequest() and SynchronousRequest().
351 A zero BufferSize doesn't seem to be prohibited, so do nothing in that case,
358 VirtioBlkReadBlocks (
359 IN EFI_BLOCK_IO_PROTOCOL
*This
,
369 if (BufferSize
== 0) {
373 Dev
= VIRTIO_BLK_FROM_BLOCK_IO (This
);
374 Status
= VerifyReadWriteRequest (
378 FALSE
// RequestIsWrite
380 if (EFI_ERROR (Status
)) {
384 return SynchronousRequest (
389 FALSE
// RequestIsWrite
395 WriteBlocks() operation for virtio-blk.
398 - UEFI Spec 2.3.1 + Errata C, 12.8 EFI Block I/O Protocol, 12.8 EFI Block I/O
399 Protocol, EFI_BLOCK_IO_PROTOCOL.WriteBlocks().
400 - Driver Writer's Guide for UEFI 2.3.1 v1.01, 24.2.3 WriteBlocks() and
401 WriteBlockEx() Implementation.
403 Parameter checks and conformant return values are implemented in
404 VerifyReadWriteRequest() and SynchronousRequest().
406 A zero BufferSize doesn't seem to be prohibited, so do nothing in that case,
413 VirtioBlkWriteBlocks (
414 IN EFI_BLOCK_IO_PROTOCOL
*This
,
424 if (BufferSize
== 0) {
428 Dev
= VIRTIO_BLK_FROM_BLOCK_IO (This
);
429 Status
= VerifyReadWriteRequest (
433 TRUE
// RequestIsWrite
435 if (EFI_ERROR (Status
)) {
439 return SynchronousRequest (
444 TRUE
// RequestIsWrite
451 FlushBlocks() operation for virtio-blk.
454 - UEFI Spec 2.3.1 + Errata C, 12.8 EFI Block I/O Protocol, 12.8 EFI Block I/O
455 Protocol, EFI_BLOCK_IO_PROTOCOL.FlushBlocks().
456 - Driver Writer's Guide for UEFI 2.3.1 v1.01, 24.2.4 FlushBlocks() and
457 FlushBlocksEx() Implementation.
459 If the underlying virtio-blk device doesn't support flushing (ie.
460 write-caching), then this function should not be called by higher layers,
461 according to EFI_BLOCK_IO_MEDIA characteristics set in VirtioBlkInit().
462 Should they do nonetheless, we do nothing, successfully.
468 VirtioBlkFlushBlocks (
469 IN EFI_BLOCK_IO_PROTOCOL
*This
474 Dev
= VIRTIO_BLK_FROM_BLOCK_IO (This
);
475 return Dev
->BlockIoMedia
.WriteCaching
?
481 TRUE
// RequestIsWrite
489 Device probe function for this driver.
491 The DXE core calls this function for any given device in order to see if the
492 driver can drive the device.
494 Specs relevant in the general sense:
496 - UEFI Spec 2.3.1 + Errata C:
497 - 6.3 Protocol Handler Services -- for accessing the underlying device
498 - 10.1 EFI Driver Binding Protocol -- for exporting ourselves
500 - Driver Writer's Guide for UEFI 2.3.1 v1.01:
501 - 5.1.3.4 OpenProtocol() and CloseProtocol() -- for accessing the
503 - 9 Driver Binding Protocol -- for exporting ourselves
505 @param[in] This The EFI_DRIVER_BINDING_PROTOCOL object
506 incorporating this driver (independently of
509 @param[in] DeviceHandle The device to probe.
511 @param[in] RemainingDevicePath Relevant only for bus drivers, ignored.
514 @retval EFI_SUCCESS The driver supports the device being probed.
516 @retval EFI_UNSUPPORTED Based on virtio-blk discovery, we do not support
519 @return Error codes from the OpenProtocol() boot service or
526 VirtioBlkDriverBindingSupported (
527 IN EFI_DRIVER_BINDING_PROTOCOL
*This
,
528 IN EFI_HANDLE DeviceHandle
,
529 IN EFI_DEVICE_PATH_PROTOCOL
*RemainingDevicePath
533 VIRTIO_DEVICE_PROTOCOL
*VirtIo
;
536 // Attempt to open the device with the VirtIo set of interfaces. On success,
537 // the protocol is "instantiated" for the VirtIo device. Covers duplicate
538 // open attempts (EFI_ALREADY_STARTED).
540 Status
= gBS
->OpenProtocol (
541 DeviceHandle
, // candidate device
542 &gVirtioDeviceProtocolGuid
, // for generic VirtIo access
543 (VOID
**)&VirtIo
, // handle to instantiate
544 This
->DriverBindingHandle
, // requestor driver identity
545 DeviceHandle
, // ControllerHandle, according to
546 // the UEFI Driver Model
547 EFI_OPEN_PROTOCOL_BY_DRIVER
// get exclusive VirtIo access to
548 // the device; to be released
550 if (EFI_ERROR (Status
)) {
554 if (VirtIo
->SubSystemDeviceId
!= VIRTIO_SUBSYSTEM_BLOCK_DEVICE
) {
555 Status
= EFI_UNSUPPORTED
;
559 // We needed VirtIo access only transitorily, to see whether we support the
562 gBS
->CloseProtocol (DeviceHandle
, &gVirtioDeviceProtocolGuid
,
563 This
->DriverBindingHandle
, DeviceHandle
);
570 Set up all BlockIo and virtio-blk aspects of this driver for the specified
573 @param[in out] Dev The driver instance to configure. The caller is
574 responsible for Dev->VirtIo's validity (ie. working IO
575 access to the underlying virtio-blk device).
577 @retval EFI_SUCCESS Setup complete.
579 @retval EFI_UNSUPPORTED The driver is unable to work with the virtio ring or
580 virtio-blk attributes the host provides.
582 @return Error codes from VirtioRingInit() or
583 VIRTIO_CFG_READ() / VIRTIO_CFG_WRITE().
600 UINT8 PhysicalBlockExp
;
601 UINT8 AlignmentOffset
;
605 PhysicalBlockExp
= 0;
610 // Execute virtio-0.9.5, 2.2.1 Device Initialization Sequence.
612 NextDevStat
= 0; // step 1 -- reset device
613 Status
= Dev
->VirtIo
->SetDeviceStatus (Dev
->VirtIo
, NextDevStat
);
614 if (EFI_ERROR (Status
)) {
618 NextDevStat
|= VSTAT_ACK
; // step 2 -- acknowledge device presence
619 Status
= Dev
->VirtIo
->SetDeviceStatus (Dev
->VirtIo
, NextDevStat
);
620 if (EFI_ERROR (Status
)) {
624 NextDevStat
|= VSTAT_DRIVER
; // step 3 -- we know how to drive it
625 Status
= Dev
->VirtIo
->SetDeviceStatus (Dev
->VirtIo
, NextDevStat
);
626 if (EFI_ERROR (Status
)) {
631 // Set Page Size - MMIO VirtIo Specific
633 Status
= Dev
->VirtIo
->SetPageSize (Dev
->VirtIo
, EFI_PAGE_SIZE
);
634 if (EFI_ERROR (Status
)) {
639 // step 4a -- retrieve and validate features
641 Status
= Dev
->VirtIo
->GetDeviceFeatures (Dev
->VirtIo
, &Features
);
642 if (EFI_ERROR (Status
)) {
646 Status
= VIRTIO_CFG_READ (Dev
, Capacity
, &NumSectors
);
647 if (EFI_ERROR (Status
)) {
650 if (NumSectors
== 0) {
651 Status
= EFI_UNSUPPORTED
;
655 if (Features
& VIRTIO_BLK_F_BLK_SIZE
) {
656 Status
= VIRTIO_CFG_READ (Dev
, BlkSize
, &BlockSize
);
657 if (EFI_ERROR (Status
)) {
660 if (BlockSize
== 0 || BlockSize
% 512 != 0 ||
661 ModU64x32 (NumSectors
, BlockSize
/ 512) != 0) {
663 // We can only handle a logical block consisting of whole sectors,
664 // and only a disk composed of whole logical blocks.
666 Status
= EFI_UNSUPPORTED
;
674 if (Features
& VIRTIO_BLK_F_TOPOLOGY
) {
675 Status
= VIRTIO_CFG_READ (Dev
, Topology
.PhysicalBlockExp
,
677 if (EFI_ERROR (Status
)) {
680 if (PhysicalBlockExp
>= 32) {
681 Status
= EFI_UNSUPPORTED
;
685 Status
= VIRTIO_CFG_READ (Dev
, Topology
.AlignmentOffset
, &AlignmentOffset
);
686 if (EFI_ERROR (Status
)) {
690 Status
= VIRTIO_CFG_READ (Dev
, Topology
.OptIoSize
, &OptIoSize
);
691 if (EFI_ERROR (Status
)) {
696 Features
&= VIRTIO_BLK_F_BLK_SIZE
| VIRTIO_BLK_F_TOPOLOGY
| VIRTIO_BLK_F_RO
|
697 VIRTIO_BLK_F_FLUSH
| VIRTIO_F_VERSION_1
;
700 // In virtio-1.0, feature negotiation is expected to complete before queue
701 // discovery, and the device can also reject the selected set of features.
703 if (Dev
->VirtIo
->Revision
>= VIRTIO_SPEC_REVISION (1, 0, 0)) {
704 Status
= Virtio10WriteFeatures (Dev
->VirtIo
, Features
, &NextDevStat
);
705 if (EFI_ERROR (Status
)) {
711 // step 4b -- allocate virtqueue
713 Status
= Dev
->VirtIo
->SetQueueSel (Dev
->VirtIo
, 0);
714 if (EFI_ERROR (Status
)) {
717 Status
= Dev
->VirtIo
->GetQueueNumMax (Dev
->VirtIo
, &QueueSize
);
718 if (EFI_ERROR (Status
)) {
721 if (QueueSize
< 3) { // SynchronousRequest() uses at most three descriptors
722 Status
= EFI_UNSUPPORTED
;
726 Status
= VirtioRingInit (Dev
->VirtIo
, QueueSize
, &Dev
->Ring
);
727 if (EFI_ERROR (Status
)) {
732 // Additional steps for MMIO: align the queue appropriately, and set the
733 // size. If anything fails from here on, we must release the ring resources.
735 Status
= Dev
->VirtIo
->SetQueueNum (Dev
->VirtIo
, QueueSize
);
736 if (EFI_ERROR (Status
)) {
740 Status
= Dev
->VirtIo
->SetQueueAlign (Dev
->VirtIo
, EFI_PAGE_SIZE
);
741 if (EFI_ERROR (Status
)) {
746 // step 4c -- Report GPFN (guest-physical frame number) of queue.
748 Status
= Dev
->VirtIo
->SetQueueAddress (Dev
->VirtIo
, &Dev
->Ring
, 0);
749 if (EFI_ERROR (Status
)) {
755 // step 5 -- Report understood features.
757 if (Dev
->VirtIo
->Revision
< VIRTIO_SPEC_REVISION (1, 0, 0)) {
758 Features
&= ~(UINT64
)VIRTIO_F_VERSION_1
;
759 Status
= Dev
->VirtIo
->SetGuestFeatures (Dev
->VirtIo
, Features
);
760 if (EFI_ERROR (Status
)) {
766 // step 6 -- initialization complete
768 NextDevStat
|= VSTAT_DRIVER_OK
;
769 Status
= Dev
->VirtIo
->SetDeviceStatus (Dev
->VirtIo
, NextDevStat
);
770 if (EFI_ERROR (Status
)) {
775 // Populate the exported interface's attributes; see UEFI spec v2.4, 12.9 EFI
776 // Block I/O Protocol.
778 Dev
->BlockIo
.Revision
= 0;
779 Dev
->BlockIo
.Media
= &Dev
->BlockIoMedia
;
780 Dev
->BlockIo
.Reset
= &VirtioBlkReset
;
781 Dev
->BlockIo
.ReadBlocks
= &VirtioBlkReadBlocks
;
782 Dev
->BlockIo
.WriteBlocks
= &VirtioBlkWriteBlocks
;
783 Dev
->BlockIo
.FlushBlocks
= &VirtioBlkFlushBlocks
;
784 Dev
->BlockIoMedia
.MediaId
= 0;
785 Dev
->BlockIoMedia
.RemovableMedia
= FALSE
;
786 Dev
->BlockIoMedia
.MediaPresent
= TRUE
;
787 Dev
->BlockIoMedia
.LogicalPartition
= FALSE
;
788 Dev
->BlockIoMedia
.ReadOnly
= (BOOLEAN
) ((Features
& VIRTIO_BLK_F_RO
) != 0);
789 Dev
->BlockIoMedia
.WriteCaching
= (BOOLEAN
) ((Features
& VIRTIO_BLK_F_FLUSH
) != 0);
790 Dev
->BlockIoMedia
.BlockSize
= BlockSize
;
791 Dev
->BlockIoMedia
.IoAlign
= 0;
792 Dev
->BlockIoMedia
.LastBlock
= DivU64x32 (NumSectors
,
793 BlockSize
/ 512) - 1;
795 DEBUG ((DEBUG_INFO
, "%a: LbaSize=0x%x[B] NumBlocks=0x%Lx[Lba]\n",
796 __FUNCTION__
, Dev
->BlockIoMedia
.BlockSize
,
797 Dev
->BlockIoMedia
.LastBlock
+ 1));
799 if (Features
& VIRTIO_BLK_F_TOPOLOGY
) {
800 Dev
->BlockIo
.Revision
= EFI_BLOCK_IO_PROTOCOL_REVISION3
;
802 Dev
->BlockIoMedia
.LowestAlignedLba
= AlignmentOffset
;
803 Dev
->BlockIoMedia
.LogicalBlocksPerPhysicalBlock
= 1u << PhysicalBlockExp
;
804 Dev
->BlockIoMedia
.OptimalTransferLengthGranularity
= OptIoSize
;
806 DEBUG ((DEBUG_INFO
, "%a: FirstAligned=0x%Lx[Lba] PhysBlkSize=0x%x[Lba]\n",
807 __FUNCTION__
, Dev
->BlockIoMedia
.LowestAlignedLba
,
808 Dev
->BlockIoMedia
.LogicalBlocksPerPhysicalBlock
));
809 DEBUG ((DEBUG_INFO
, "%a: OptimalTransferLengthGranularity=0x%x[Lba]\n",
810 __FUNCTION__
, Dev
->BlockIoMedia
.OptimalTransferLengthGranularity
));
815 VirtioRingUninit (Dev
->VirtIo
, &Dev
->Ring
);
819 // Notify the host about our failure to setup: virtio-0.9.5, 2.2.2.1 Device
820 // Status. VirtIo access failure here should not mask the original error.
822 NextDevStat
|= VSTAT_FAILED
;
823 Dev
->VirtIo
->SetDeviceStatus (Dev
->VirtIo
, NextDevStat
);
825 return Status
; // reached only via Failed above
831 Uninitialize the internals of a virtio-blk device that has been successfully
832 set up with VirtioBlkInit().
834 @param[in out] Dev The device to clean up.
846 // Reset the virtual device -- see virtio-0.9.5, 2.2.2.1 Device Status. When
847 // VIRTIO_CFG_WRITE() returns, the host will have learned to stay away from
848 // the old comms area.
850 Dev
->VirtIo
->SetDeviceStatus (Dev
->VirtIo
, 0);
852 VirtioRingUninit (Dev
->VirtIo
, &Dev
->Ring
);
854 SetMem (&Dev
->BlockIo
, sizeof Dev
->BlockIo
, 0x00);
855 SetMem (&Dev
->BlockIoMedia
, sizeof Dev
->BlockIoMedia
, 0x00);
861 Event notification function enqueued by ExitBootServices().
863 @param[in] Event Event whose notification function is being invoked.
865 @param[in] Context Pointer to the VBLK_DEV structure.
880 // Reset the device. This causes the hypervisor to forget about the virtio
883 // We allocated said ring in EfiBootServicesData type memory, and code
884 // executing after ExitBootServices() is permitted to overwrite it.
887 Dev
->VirtIo
->SetDeviceStatus (Dev
->VirtIo
, 0);
892 After we've pronounced support for a specific device in
893 DriverBindingSupported(), we start managing said device (passed in by the
894 Driver Execution Environment) with the following service.
896 See DriverBindingSupported() for specification references.
898 @param[in] This The EFI_DRIVER_BINDING_PROTOCOL object
899 incorporating this driver (independently of
902 @param[in] DeviceHandle The supported device to drive.
904 @param[in] RemainingDevicePath Relevant only for bus drivers, ignored.
907 @retval EFI_SUCCESS Driver instance has been created and
908 initialized for the virtio-blk device, it
909 is now accessible via EFI_BLOCK_IO_PROTOCOL.
911 @retval EFI_OUT_OF_RESOURCES Memory allocation failed.
913 @return Error codes from the OpenProtocol() boot
914 service, the VirtIo protocol, VirtioBlkInit(),
915 or the InstallProtocolInterface() boot service.
921 VirtioBlkDriverBindingStart (
922 IN EFI_DRIVER_BINDING_PROTOCOL
*This
,
923 IN EFI_HANDLE DeviceHandle
,
924 IN EFI_DEVICE_PATH_PROTOCOL
*RemainingDevicePath
930 Dev
= (VBLK_DEV
*) AllocateZeroPool (sizeof *Dev
);
932 return EFI_OUT_OF_RESOURCES
;
935 Status
= gBS
->OpenProtocol (DeviceHandle
, &gVirtioDeviceProtocolGuid
,
936 (VOID
**)&Dev
->VirtIo
, This
->DriverBindingHandle
,
937 DeviceHandle
, EFI_OPEN_PROTOCOL_BY_DRIVER
);
938 if (EFI_ERROR (Status
)) {
943 // VirtIo access granted, configure virtio-blk device.
945 Status
= VirtioBlkInit (Dev
);
946 if (EFI_ERROR (Status
)) {
950 Status
= gBS
->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES
, TPL_CALLBACK
,
951 &VirtioBlkExitBoot
, Dev
, &Dev
->ExitBoot
);
952 if (EFI_ERROR (Status
)) {
957 // Setup complete, attempt to export the driver instance's BlockIo interface.
959 Dev
->Signature
= VBLK_SIG
;
960 Status
= gBS
->InstallProtocolInterface (&DeviceHandle
,
961 &gEfiBlockIoProtocolGuid
, EFI_NATIVE_INTERFACE
,
963 if (EFI_ERROR (Status
)) {
970 gBS
->CloseEvent (Dev
->ExitBoot
);
973 VirtioBlkUninit (Dev
);
976 gBS
->CloseProtocol (DeviceHandle
, &gVirtioDeviceProtocolGuid
,
977 This
->DriverBindingHandle
, DeviceHandle
);
988 Stop driving a virtio-blk device and remove its BlockIo interface.
990 This function replays the success path of DriverBindingStart() in reverse.
991 The host side virtio-blk device is reset, so that the OS boot loader or the
992 OS may reinitialize it.
994 @param[in] This The EFI_DRIVER_BINDING_PROTOCOL object
995 incorporating this driver (independently of any
998 @param[in] DeviceHandle Stop driving this device.
1000 @param[in] NumberOfChildren Since this function belongs to a device driver
1001 only (as opposed to a bus driver), the caller
1002 environment sets NumberOfChildren to zero, and
1005 @param[in] ChildHandleBuffer Ignored (corresponding to NumberOfChildren).
1011 VirtioBlkDriverBindingStop (
1012 IN EFI_DRIVER_BINDING_PROTOCOL
*This
,
1013 IN EFI_HANDLE DeviceHandle
,
1014 IN UINTN NumberOfChildren
,
1015 IN EFI_HANDLE
*ChildHandleBuffer
1019 EFI_BLOCK_IO_PROTOCOL
*BlockIo
;
1022 Status
= gBS
->OpenProtocol (
1023 DeviceHandle
, // candidate device
1024 &gEfiBlockIoProtocolGuid
, // retrieve the BlockIo iface
1025 (VOID
**)&BlockIo
, // target pointer
1026 This
->DriverBindingHandle
, // requestor driver identity
1027 DeviceHandle
, // requesting lookup for dev.
1028 EFI_OPEN_PROTOCOL_GET_PROTOCOL
// lookup only, no ref. added
1030 if (EFI_ERROR (Status
)) {
1034 Dev
= VIRTIO_BLK_FROM_BLOCK_IO (BlockIo
);
1037 // Handle Stop() requests for in-use driver instances gracefully.
1039 Status
= gBS
->UninstallProtocolInterface (DeviceHandle
,
1040 &gEfiBlockIoProtocolGuid
, &Dev
->BlockIo
);
1041 if (EFI_ERROR (Status
)) {
1045 gBS
->CloseEvent (Dev
->ExitBoot
);
1047 VirtioBlkUninit (Dev
);
1049 gBS
->CloseProtocol (DeviceHandle
, &gVirtioDeviceProtocolGuid
,
1050 This
->DriverBindingHandle
, DeviceHandle
);
1059 // The static object that groups the Supported() (ie. probe), Start() and
1060 // Stop() functions of the driver together. Refer to UEFI Spec 2.3.1 + Errata
1061 // C, 10.1 EFI Driver Binding Protocol.
1063 STATIC EFI_DRIVER_BINDING_PROTOCOL gDriverBinding
= {
1064 &VirtioBlkDriverBindingSupported
,
1065 &VirtioBlkDriverBindingStart
,
1066 &VirtioBlkDriverBindingStop
,
1067 0x10, // Version, must be in [0x10 .. 0xFFFFFFEF] for IHV-developed drivers
1068 NULL
, // ImageHandle, to be overwritten by
1069 // EfiLibInstallDriverBindingComponentName2() in VirtioBlkEntryPoint()
1070 NULL
// DriverBindingHandle, ditto
1075 // The purpose of the following scaffolding (EFI_COMPONENT_NAME_PROTOCOL and
1076 // EFI_COMPONENT_NAME2_PROTOCOL implementation) is to format the driver's name
1077 // in English, for display on standard console devices. This is recommended for
1078 // UEFI drivers that follow the UEFI Driver Model. Refer to the Driver Writer's
1079 // Guide for UEFI 2.3.1 v1.01, 11 UEFI Driver and Controller Names.
1081 // Device type names ("Virtio Block Device") are not formatted because the
1082 // driver supports only that device type. Therefore the driver name suffices
1083 // for unambiguous identification.
1087 EFI_UNICODE_STRING_TABLE mDriverNameTable
[] = {
1088 { "eng;en", L
"Virtio Block Driver" },
1093 EFI_COMPONENT_NAME_PROTOCOL gComponentName
;
1097 VirtioBlkGetDriverName (
1098 IN EFI_COMPONENT_NAME_PROTOCOL
*This
,
1100 OUT CHAR16
**DriverName
1103 return LookupUnicodeString2 (
1105 This
->SupportedLanguages
,
1108 (BOOLEAN
)(This
== &gComponentName
) // Iso639Language
1114 VirtioBlkGetDeviceName (
1115 IN EFI_COMPONENT_NAME_PROTOCOL
*This
,
1116 IN EFI_HANDLE DeviceHandle
,
1117 IN EFI_HANDLE ChildHandle
,
1119 OUT CHAR16
**ControllerName
1122 return EFI_UNSUPPORTED
;
1126 EFI_COMPONENT_NAME_PROTOCOL gComponentName
= {
1127 &VirtioBlkGetDriverName
,
1128 &VirtioBlkGetDeviceName
,
1129 "eng" // SupportedLanguages, ISO 639-2 language codes
1133 EFI_COMPONENT_NAME2_PROTOCOL gComponentName2
= {
1134 (EFI_COMPONENT_NAME2_GET_DRIVER_NAME
) &VirtioBlkGetDriverName
,
1135 (EFI_COMPONENT_NAME2_GET_CONTROLLER_NAME
) &VirtioBlkGetDeviceName
,
1136 "en" // SupportedLanguages, RFC 4646 language codes
1141 // Entry point of this driver.
1145 VirtioBlkEntryPoint (
1146 IN EFI_HANDLE ImageHandle
,
1147 IN EFI_SYSTEM_TABLE
*SystemTable
1150 return EfiLibInstallDriverBindingComponentName2 (