mirror of https://github.com/acidanthera/audk.git
OvmfPkg/VirtioFsDxe: add a scatter-gather list data type
In preparation for the variously structured FUSE request/response exchanges that virtio-fs uses, introduce a scatter-gather list data type. This will let us express FUSE request-response pairs flexibly. Add a function for validating whether a (request buffer list, response buffer list) pair is well-formed, and supported by the Virtio Filesystem device's queue depth. Add another function for mapping and submitting a validated pair of scatter-gather lists to the Virtio Filesystem device. Cc: Ard Biesheuvel <ard.biesheuvel@arm.com> Cc: Jordan Justen <jordan.l.justen@intel.com> Cc: Philippe Mathieu-Daudé <philmd@redhat.com> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3097 Signed-off-by: Laszlo Ersek <lersek@redhat.com> Message-Id: <20201216211125.19496-6-lersek@redhat.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@arm.com> [lersek@redhat.com: suppress useless VS2019 warning about signed/unsigned comparison in VirtioFsSgListsValidate()]
This commit is contained in:
Laszlo Ersek
mergify[bot]
parent
eaa7115d60
commit
6578cacb46
|
|
@ -297,3 +297,404 @@ VirtioFsExitBoot (
|
|||
VirtioFsAsVoid, VirtioFs->Label));
|
||||
VirtioFs->Virtio->SetDeviceStatus (VirtioFs->Virtio, 0);
|
||||
}
|
||||
|
||||
/**
|
||||
Validate two VIRTIO_FS_SCATTER_GATHER_LIST objects -- list of request
|
||||
buffers, list of response buffers -- together.
|
||||
|
||||
On input, the caller is required to populate the following fields:
|
||||
- VIRTIO_FS_IO_VECTOR.Buffer,
|
||||
- VIRTIO_FS_IO_VECTOR.Size,
|
||||
- VIRTIO_FS_SCATTER_GATHER_LIST.IoVec,
|
||||
- VIRTIO_FS_SCATTER_GATHER_LIST.NumVec.
|
||||
|
||||
On output (on successful return), the following fields will be
|
||||
zero-initialized:
|
||||
- VIRTIO_FS_IO_VECTOR.Mapped,
|
||||
- VIRTIO_FS_IO_VECTOR.MappedAddress,
|
||||
- VIRTIO_FS_IO_VECTOR.Mapping,
|
||||
- VIRTIO_FS_IO_VECTOR.Transferred.
|
||||
|
||||
On output (on successful return), the following fields will be calculated:
|
||||
- VIRTIO_FS_SCATTER_GATHER_LIST.TotalSize.
|
||||
|
||||
The function may only be called after VirtioFsInit() returns successfully and
|
||||
before VirtioFsUninit() is called.
|
||||
|
||||
@param[in] VirtioFs The Virtio Filesystem device that the
|
||||
request-response exchange, expressed via
|
||||
RequestSgList and ResponseSgList, will be
|
||||
submitted to.
|
||||
|
||||
@param[in,out] RequestSgList The scatter-gather list that describes the
|
||||
request part of the exchange -- the buffers
|
||||
that should be sent to the Virtio Filesystem
|
||||
device in the virtio transfer.
|
||||
|
||||
@param[in,out] ResponseSgList The scatter-gather list that describes the
|
||||
response part of the exchange -- the buffers
|
||||
that the Virtio Filesystem device should
|
||||
populate in the virtio transfer. May be NULL
|
||||
if the exchange with the Virtio Filesystem
|
||||
device consists of a request only, with the
|
||||
response part omitted altogether.
|
||||
|
||||
@retval EFI_SUCCESS RequestSgList and ResponseSgList have been
|
||||
validated, output fields have been set.
|
||||
|
||||
@retval EFI_INVALID_PARAMETER RequestSgList is NULL.
|
||||
|
||||
@retval EFI_INVALID_PARAMETER On input, a
|
||||
VIRTIO_FS_SCATTER_GATHER_LIST.IoVec field is
|
||||
NULL, or a
|
||||
VIRTIO_FS_SCATTER_GATHER_LIST.NumVec field is
|
||||
zero.
|
||||
|
||||
@retval EFI_INVALID_PARAMETER On input, a VIRTIO_FS_IO_VECTOR.Buffer field
|
||||
is NULL, or a VIRTIO_FS_IO_VECTOR.Size field
|
||||
is zero.
|
||||
|
||||
@retval EFI_UNSUPPORTED (RequestSgList->NumVec +
|
||||
ResponseSgList->NumVec) exceeds
|
||||
VirtioFs->QueueSize, meaning that the total
|
||||
list of buffers cannot be placed on the virtio
|
||||
queue in a single descriptor chain (with one
|
||||
descriptor per buffer).
|
||||
|
||||
@retval EFI_UNSUPPORTED One of the
|
||||
VIRTIO_FS_SCATTER_GATHER_LIST.TotalSize fields
|
||||
would exceed MAX_UINT32.
|
||||
**/
|
||||
EFI_STATUS
|
||||
VirtioFsSgListsValidate (
|
||||
IN VIRTIO_FS *VirtioFs,
|
||||
IN OUT VIRTIO_FS_SCATTER_GATHER_LIST *RequestSgList,
|
||||
IN OUT VIRTIO_FS_SCATTER_GATHER_LIST *ResponseSgList OPTIONAL
|
||||
)
|
||||
{
|
||||
VIRTIO_FS_SCATTER_GATHER_LIST *SgListParam[2];
|
||||
UINT16 DescriptorsNeeded;
|
||||
UINTN ListId;
|
||||
|
||||
if (RequestSgList == NULL) {
|
||||
return EFI_INVALID_PARAMETER;
|
||||
}
|
||||
|
||||
SgListParam[0] = RequestSgList;
|
||||
SgListParam[1] = ResponseSgList;
|
||||
|
||||
DescriptorsNeeded = 0;
|
||||
for (ListId = 0; ListId < ARRAY_SIZE (SgListParam); ListId++) {
|
||||
VIRTIO_FS_SCATTER_GATHER_LIST *SgList;
|
||||
UINT32 SgListTotalSize;
|
||||
UINTN IoVecIdx;
|
||||
|
||||
SgList = SgListParam[ListId];
|
||||
if (SgList == NULL) {
|
||||
continue;
|
||||
}
|
||||
//
|
||||
// Sanity-check SgList -- it must provide at least one IO Vector.
|
||||
//
|
||||
if (SgList->IoVec == NULL || SgList->NumVec == 0) {
|
||||
return EFI_INVALID_PARAMETER;
|
||||
}
|
||||
//
|
||||
// Make sure that, for each IO Vector in this SgList, a virtio descriptor
|
||||
// can be added to the virtio queue, after the other descriptors added
|
||||
// previously.
|
||||
//
|
||||
if (SgList->NumVec > (UINTN)(MAX_UINT16 - DescriptorsNeeded) ||
|
||||
DescriptorsNeeded + SgList->NumVec > VirtioFs->QueueSize) {
|
||||
return EFI_UNSUPPORTED;
|
||||
}
|
||||
DescriptorsNeeded += (UINT16)SgList->NumVec;
|
||||
|
||||
SgListTotalSize = 0;
|
||||
for (IoVecIdx = 0; IoVecIdx < SgList->NumVec; IoVecIdx++) {
|
||||
VIRTIO_FS_IO_VECTOR *IoVec;
|
||||
|
||||
IoVec = &SgList->IoVec[IoVecIdx];
|
||||
//
|
||||
// Sanity-check this IoVec -- it must describe a non-empty buffer.
|
||||
//
|
||||
if (IoVec->Buffer == NULL || IoVec->Size == 0) {
|
||||
return EFI_INVALID_PARAMETER;
|
||||
}
|
||||
//
|
||||
// Make sure the cumulative size of all IO Vectors in this SgList remains
|
||||
// expressible as a UINT32.
|
||||
//
|
||||
if (IoVec->Size > MAX_UINT32 - SgListTotalSize) {
|
||||
return EFI_UNSUPPORTED;
|
||||
}
|
||||
SgListTotalSize += (UINT32)IoVec->Size;
|
||||
|
||||
//
|
||||
// Initialize those fields in this IO Vector that will be updated in
|
||||
// relation to mapping / transfer.
|
||||
//
|
||||
IoVec->Mapped = FALSE;
|
||||
IoVec->MappedAddress = 0;
|
||||
IoVec->Mapping = NULL;
|
||||
IoVec->Transferred = 0;
|
||||
}
|
||||
|
||||
//
|
||||
// Store the cumulative size of all IO Vectors that we have calculated in
|
||||
// this SgList.
|
||||
//
|
||||
SgList->TotalSize = SgListTotalSize;
|
||||
}
|
||||
|
||||
return EFI_SUCCESS;
|
||||
}
|
||||
|
||||
/**
|
||||
Submit a validated pair of (request buffer list, response buffer list) to the
|
||||
Virtio Filesystem device.
|
||||
|
||||
On input, the pair of VIRTIO_FS_SCATTER_GATHER_LIST objects must have been
|
||||
validated together, using the VirtioFsSgListsValidate() function.
|
||||
|
||||
On output (on successful return), the following fields will be re-initialized
|
||||
to zero (after temporarily setting them to different values):
|
||||
- VIRTIO_FS_IO_VECTOR.Mapped,
|
||||
- VIRTIO_FS_IO_VECTOR.MappedAddress,
|
||||
- VIRTIO_FS_IO_VECTOR.Mapping.
|
||||
|
||||
On output (on successful return), the following fields will be calculated:
|
||||
- VIRTIO_FS_IO_VECTOR.Transferred.
|
||||
|
||||
The function may only be called after VirtioFsInit() returns successfully and
|
||||
before VirtioFsUninit() is called.
|
||||
|
||||
@param[in,out] VirtioFs The Virtio Filesystem device that the
|
||||
request-response exchange, expressed via
|
||||
RequestSgList and ResponseSgList, should now
|
||||
be submitted to.
|
||||
|
||||
@param[in,out] RequestSgList The scatter-gather list that describes the
|
||||
request part of the exchange -- the buffers
|
||||
that should be sent to the Virtio Filesystem
|
||||
device in the virtio transfer.
|
||||
|
||||
@param[in,out] ResponseSgList The scatter-gather list that describes the
|
||||
response part of the exchange -- the buffers
|
||||
that the Virtio Filesystem device should
|
||||
populate in the virtio transfer. May be NULL
|
||||
if and only if NULL was passed to
|
||||
VirtioFsSgListsValidate() as ResponseSgList.
|
||||
|
||||
@retval EFI_SUCCESS Transfer complete. The caller should investigate
|
||||
the VIRTIO_FS_IO_VECTOR.Transferred fields in
|
||||
ResponseSgList, to ensure coverage of the relevant
|
||||
response buffers. Subsequently, the caller should
|
||||
investigate the contents of those buffers.
|
||||
|
||||
@retval EFI_DEVICE_ERROR The Virtio Filesystem device reported populating
|
||||
more response bytes than ResponseSgList->TotalSize.
|
||||
|
||||
@return Error codes propagated from
|
||||
VirtioMapAllBytesInSharedBuffer(), VirtioFlush(),
|
||||
or VirtioFs->Virtio->UnmapSharedBuffer().
|
||||
**/
|
||||
EFI_STATUS
|
||||
VirtioFsSgListsSubmit (
|
||||
IN OUT VIRTIO_FS *VirtioFs,
|
||||
IN OUT VIRTIO_FS_SCATTER_GATHER_LIST *RequestSgList,
|
||||
IN OUT VIRTIO_FS_SCATTER_GATHER_LIST *ResponseSgList OPTIONAL
|
||||
)
|
||||
{
|
||||
VIRTIO_FS_SCATTER_GATHER_LIST *SgListParam[2];
|
||||
VIRTIO_MAP_OPERATION SgListVirtioMapOp[ARRAY_SIZE (SgListParam)];
|
||||
UINT16 SgListDescriptorFlag[ARRAY_SIZE (SgListParam)];
|
||||
UINTN ListId;
|
||||
VIRTIO_FS_SCATTER_GATHER_LIST *SgList;
|
||||
UINTN IoVecIdx;
|
||||
VIRTIO_FS_IO_VECTOR *IoVec;
|
||||
EFI_STATUS Status;
|
||||
DESC_INDICES Indices;
|
||||
UINT32 TotalBytesWrittenByDevice;
|
||||
UINT32 BytesPermittedForWrite;
|
||||
|
||||
SgListParam[0] = RequestSgList;
|
||||
SgListVirtioMapOp[0] = VirtioOperationBusMasterRead;
|
||||
SgListDescriptorFlag[0] = 0;
|
||||
|
||||
SgListParam[1] = ResponseSgList;
|
||||
SgListVirtioMapOp[1] = VirtioOperationBusMasterWrite;
|
||||
SgListDescriptorFlag[1] = VRING_DESC_F_WRITE;
|
||||
|
||||
//
|
||||
// Map all IO Vectors.
|
||||
//
|
||||
for (ListId = 0; ListId < ARRAY_SIZE (SgListParam); ListId++) {
|
||||
SgList = SgListParam[ListId];
|
||||
if (SgList == NULL) {
|
||||
continue;
|
||||
}
|
||||
for (IoVecIdx = 0; IoVecIdx < SgList->NumVec; IoVecIdx++) {
|
||||
IoVec = &SgList->IoVec[IoVecIdx];
|
||||
//
|
||||
// Map this IO Vector.
|
||||
//
|
||||
Status = VirtioMapAllBytesInSharedBuffer (
|
||||
VirtioFs->Virtio,
|
||||
SgListVirtioMapOp[ListId],
|
||||
IoVec->Buffer,
|
||||
IoVec->Size,
|
||||
&IoVec->MappedAddress,
|
||||
&IoVec->Mapping
|
||||
);
|
||||
if (EFI_ERROR (Status)) {
|
||||
goto Unmap;
|
||||
}
|
||||
IoVec->Mapped = TRUE;
|
||||
}
|
||||
}
|
||||
|
||||
//
|
||||
// Compose the descriptor chain.
|
||||
//
|
||||
VirtioPrepare (&VirtioFs->Ring, &Indices);
|
||||
for (ListId = 0; ListId < ARRAY_SIZE (SgListParam); ListId++) {
|
||||
SgList = SgListParam[ListId];
|
||||
if (SgList == NULL) {
|
||||
continue;
|
||||
}
|
||||
for (IoVecIdx = 0; IoVecIdx < SgList->NumVec; IoVecIdx++) {
|
||||
UINT16 NextFlag;
|
||||
|
||||
IoVec = &SgList->IoVec[IoVecIdx];
|
||||
//
|
||||
// Set VRING_DESC_F_NEXT on all except the very last descriptor.
|
||||
//
|
||||
NextFlag = VRING_DESC_F_NEXT;
|
||||
if (ListId == ARRAY_SIZE (SgListParam) - 1 &&
|
||||
IoVecIdx == SgList->NumVec - 1) {
|
||||
NextFlag = 0;
|
||||
}
|
||||
VirtioAppendDesc (
|
||||
&VirtioFs->Ring,
|
||||
IoVec->MappedAddress,
|
||||
(UINT32)IoVec->Size,
|
||||
SgListDescriptorFlag[ListId] | NextFlag,
|
||||
&Indices
|
||||
);
|
||||
}
|
||||
}
|
||||
|
||||
//
|
||||
// Submit the descriptor chain.
|
||||
//
|
||||
Status = VirtioFlush (VirtioFs->Virtio, VIRTIO_FS_REQUEST_QUEUE,
|
||||
&VirtioFs->Ring, &Indices, &TotalBytesWrittenByDevice);
|
||||
if (EFI_ERROR (Status)) {
|
||||
goto Unmap;
|
||||
}
|
||||
|
||||
//
|
||||
// Sanity-check: the Virtio Filesystem device should not have written more
|
||||
// bytes than what we offered buffers for.
|
||||
//
|
||||
if (ResponseSgList == NULL) {
|
||||
BytesPermittedForWrite = 0;
|
||||
} else {
|
||||
BytesPermittedForWrite = ResponseSgList->TotalSize;
|
||||
}
|
||||
if (TotalBytesWrittenByDevice > BytesPermittedForWrite) {
|
||||
Status = EFI_DEVICE_ERROR;
|
||||
goto Unmap;
|
||||
}
|
||||
|
||||
//
|
||||
// Update the transfer sizes in the IO Vectors.
|
||||
//
|
||||
for (ListId = 0; ListId < ARRAY_SIZE (SgListParam); ListId++) {
|
||||
SgList = SgListParam[ListId];
|
||||
if (SgList == NULL) {
|
||||
continue;
|
||||
}
|
||||
for (IoVecIdx = 0; IoVecIdx < SgList->NumVec; IoVecIdx++) {
|
||||
IoVec = &SgList->IoVec[IoVecIdx];
|
||||
if (SgListVirtioMapOp[ListId] == VirtioOperationBusMasterRead) {
|
||||
//
|
||||
// We report that the Virtio Filesystem device has read all buffers in
|
||||
// the request.
|
||||
//
|
||||
IoVec->Transferred = IoVec->Size;
|
||||
} else {
|
||||
//
|
||||
// Regarding the response, calculate how much of the current IO Vector
|
||||
// has been populated by the Virtio Filesystem device. In
|
||||
// "TotalBytesWrittenByDevice", VirtioFlush() reported the total count
|
||||
// across all device-writeable descriptors, in the order they were
|
||||
// chained on the ring.
|
||||
//
|
||||
IoVec->Transferred = MIN ((UINTN)TotalBytesWrittenByDevice,
|
||||
IoVec->Size);
|
||||
TotalBytesWrittenByDevice -= (UINT32)IoVec->Transferred;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
//
|
||||
// By now, "TotalBytesWrittenByDevice" has been exhausted.
|
||||
//
|
||||
ASSERT (TotalBytesWrittenByDevice == 0);
|
||||
|
||||
//
|
||||
// We've succeeded; fall through.
|
||||
//
|
||||
Unmap:
|
||||
//
|
||||
// Unmap all mapped IO Vectors on both the success and the error paths. The
|
||||
// unmapping occurs in reverse order of mapping, in an attempt to avoid
|
||||
// memory fragmentation.
|
||||
//
|
||||
ListId = ARRAY_SIZE (SgListParam);
|
||||
while (ListId > 0) {
|
||||
--ListId;
|
||||
SgList = SgListParam[ListId];
|
||||
if (SgList == NULL) {
|
||||
continue;
|
||||
}
|
||||
IoVecIdx = SgList->NumVec;
|
||||
while (IoVecIdx > 0) {
|
||||
EFI_STATUS UnmapStatus;
|
||||
|
||||
--IoVecIdx;
|
||||
IoVec = &SgList->IoVec[IoVecIdx];
|
||||
//
|
||||
// Unmap this IO Vector, if it has been mapped.
|
||||
//
|
||||
if (!IoVec->Mapped) {
|
||||
continue;
|
||||
}
|
||||
UnmapStatus = VirtioFs->Virtio->UnmapSharedBuffer (VirtioFs->Virtio,
|
||||
IoVec->Mapping);
|
||||
//
|
||||
// Re-set the following fields to the values they initially got from
|
||||
// VirtioFsSgListsValidate() -- the above unmapping attempt is considered
|
||||
// final, even if it fails.
|
||||
//
|
||||
IoVec->Mapped = FALSE;
|
||||
IoVec->MappedAddress = 0;
|
||||
IoVec->Mapping = NULL;
|
||||
|
||||
//
|
||||
// If we are on the success path, but the unmapping failed, we need to
|
||||
// transparently flip to the failure path -- the caller must learn they
|
||||
// should not consult the response buffers.
|
||||
//
|
||||
// The branch below can be taken at most once.
|
||||
//
|
||||
if (!EFI_ERROR (Status) && EFI_ERROR (UnmapStatus)) {
|
||||
Status = UnmapStatus;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return Status;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -51,6 +51,52 @@ typedef struct {
|
|||
#define VIRTIO_FS_FROM_SIMPLE_FS(SimpleFsReference) \
|
||||
CR (SimpleFsReference, VIRTIO_FS, SimpleFs, VIRTIO_FS_SIG);
|
||||
|
||||
//
|
||||
// Structure for describing a contiguous buffer, potentially mapped for Virtio
|
||||
// transfer.
|
||||
//
|
||||
typedef struct {
|
||||
//
|
||||
// The following fields originate from the owner of the buffer.
|
||||
//
|
||||
VOID *Buffer;
|
||||
UINTN Size;
|
||||
//
|
||||
// All of the fields below, until the end of the structure, are
|
||||
// zero-initialized when the structure is initially validated.
|
||||
//
|
||||
// Mapped, MappedAddress and Mapping are updated when the buffer is mapped
|
||||
// for VirtioOperationBusMasterRead or VirtioOperationBusMasterWrite. They
|
||||
// are again updated when the buffer is unmapped.
|
||||
//
|
||||
BOOLEAN Mapped;
|
||||
EFI_PHYSICAL_ADDRESS MappedAddress;
|
||||
VOID *Mapping;
|
||||
//
|
||||
// Transferred is updated after VirtioFlush() returns successfully:
|
||||
// - for VirtioOperationBusMasterRead, Transferred is set to Size;
|
||||
// - for VirtioOperationBusMasterWrite, Transferred is calculated from the
|
||||
// UsedLen output parameter of VirtioFlush().
|
||||
//
|
||||
UINTN Transferred;
|
||||
} VIRTIO_FS_IO_VECTOR;
|
||||
|
||||
//
|
||||
// Structure for describing a list of IO Vectors.
|
||||
//
|
||||
typedef struct {
|
||||
//
|
||||
// The following fields originate from the owner of the buffers.
|
||||
//
|
||||
VIRTIO_FS_IO_VECTOR *IoVec;
|
||||
UINTN NumVec;
|
||||
//
|
||||
// TotalSize is calculated when the scatter-gather list is initially
|
||||
// validated.
|
||||
//
|
||||
UINT32 TotalSize;
|
||||
} VIRTIO_FS_SCATTER_GATHER_LIST;
|
||||
|
||||
//
|
||||
// Initialization and helper routines for the Virtio Filesystem device.
|
||||
//
|
||||
|
|
@ -72,6 +118,20 @@ VirtioFsExitBoot (
|
|||
IN VOID *VirtioFsAsVoid
|
||||
);
|
||||
|
||||
EFI_STATUS
|
||||
VirtioFsSgListsValidate (
|
||||
IN VIRTIO_FS *VirtioFs,
|
||||
IN OUT VIRTIO_FS_SCATTER_GATHER_LIST *RequestSgList,
|
||||
IN OUT VIRTIO_FS_SCATTER_GATHER_LIST *ResponseSgList OPTIONAL
|
||||
);
|
||||
|
||||
EFI_STATUS
|
||||
VirtioFsSgListsSubmit (
|
||||
IN OUT VIRTIO_FS *VirtioFs,
|
||||
IN OUT VIRTIO_FS_SCATTER_GATHER_LIST *RequestSgList,
|
||||
IN OUT VIRTIO_FS_SCATTER_GATHER_LIST *ResponseSgList OPTIONAL
|
||||
);
|
||||
|
||||
//
|
||||
// EFI_SIMPLE_FILE_SYSTEM_PROTOCOL member functions for the Virtio Filesystem
|
||||
// driver.
|
||||
|
|
|
|||
Loading…
Reference in New Issue