static NTSTATUS
PvfsDoZctMemoryReadIo(
IN PPVFS_ZCT_CONTEXT pZctContext,
OUT PLW_ZCT_VECTOR pZct,
IN ULONG BufferLength,
IN LONG64 Offset,
OUT PULONG pBytesRead
)
{
NTSTATUS ntError = STATUS_UNSUCCESSFUL;
ULONG totalBytesRead = 0;
LW_ZCT_ENTRY entry = { 0 };
ntError = PvfsDoReadIo(pZctContext->pCcb,
pZctContext->pBuffer,
BufferLength,
Offset,
&totalBytesRead);
BAIL_ON_NT_STATUS(ntError);
if (totalBytesRead > 0)
{
entry.Type = LW_ZCT_ENTRY_TYPE_MEMORY;
entry.Length = totalBytesRead;
entry.Data.Memory.Buffer = pZctContext->pBuffer;
ntError = LwZctAppend(pZct, &entry, 1);
BAIL_ON_NT_STATUS(ntError);
}
cleanup:
*pBytesRead = totalBytesRead;
return ntError;
error:
totalBytesRead = 0;
goto cleanup;
}
static
NTSTATUS
PvfsReadFileWithContext(
PVOID pContext
)
{
NTSTATUS ntError = STATUS_UNSUCCESSFUL;
PPVFS_PENDING_READ pReadCtx = (PPVFS_PENDING_READ)pContext;
PIRP pIrp = pReadCtx->pIrpContext->pIrp;
PPVFS_CCB pCcb = pReadCtx->pCcb;
ULONG bufLen = pIrp->Args.ReadWrite.Length;
ULONG Key = pIrp->Args.ReadWrite.Key ? *pIrp->Args.ReadWrite.Key : 0;
ULONG totalBytesRead = 0;
ULONG64 Offset = 0;
BOOLEAN bMutexLocked = FALSE;
/* Enter critical region - ReadFile() needs to fill
the buffer atomically while it may take several read()
calls */
LWIO_LOCK_MUTEX(bMutexLocked, &pCcb->ControlBlock);
if (pIrp->Args.ReadWrite.ByteOffset) {
Offset = *pIrp->Args.ReadWrite.ByteOffset;
} else {
off_t offset = 0;
ntError = PvfsSysLseek(pCcb->fd, 0, SEEK_CUR, &offset);
BAIL_ON_NT_STATUS(ntError);
Offset = offset;
}
ntError = PvfsCheckLockedRegion(
pCcb,
PVFS_OPERATION_READ,
Key,
Offset,
bufLen);
BAIL_ON_NT_STATUS(ntError);
if (pReadCtx->pZctContext)
{
ntError = PvfsDoZctReadIo(pReadCtx->pZctContext,
pIrp->Args.ReadWrite.Zct,
bufLen,
Offset,
&totalBytesRead);
BAIL_ON_NT_STATUS(ntError);
}
else
{
ntError = PvfsDoReadIo(pCcb,
pIrp->Args.ReadWrite.Buffer,
bufLen,
Offset,
&totalBytesRead);
BAIL_ON_NT_STATUS(ntError);
}
/* Can only get here is the I/O was completed successfully */
pIrp->IoStatusBlock.BytesTransferred = totalBytesRead;
if (bufLen == 0)
{
ntError = STATUS_SUCCESS;
}
else
{
ntError = (totalBytesRead > 0) ?
STATUS_SUCCESS :
STATUS_END_OF_FILE;
}
if (pReadCtx->pZctContext && (STATUS_SUCCESS == ntError))
{
/* Save the ZCT context for complete */
pIrp->Args.ReadWrite.ZctCompletionContext = pReadCtx->pZctContext;
/* Cannot fail */
ntError = PvfsListAddTail(
pCcb->pZctContextList,
&pReadCtx->pZctContext->CcbLinks);
BAIL_ON_NT_STATUS(ntError);
pReadCtx->pZctContext = NULL;
}
pCcb->ChangeEvent |= FILE_NOTIFY_CHANGE_LAST_ACCESS;
cleanup:
LWIO_UNLOCK_MUTEX(bMutexLocked, &pCcb->ControlBlock);
return ntError;
error:
goto cleanup;
}
