PBL_BLOCK_DESCRIPTOR
MmBapFindBlockInformation (
ULONG BlockId
)
{
ULONG EntryId;
/* Find the block that matches */
EntryId = BlockId;
return BlTblFindEntry(MmBlockAllocatorTable,
MmBlockAllocatorTableEntries,
&EntryId,
MmBapCompareBlockAllocatorTableEntry,
UlongToPtr(EntryId),
NULL,
NULL,
NULL);
}
NTSTATUS
FileIoOpen (
_In_ ULONG DeviceId,
_In_ PWCHAR FileName,
_In_ ULONG Flags,
_In_ ULONG Unknown,
_In_ PBL_TBL_LOOKUP_ROUTINE CompareRoutine,
_Out_opt_ PBL_FILE_ENTRY *NewFileEntry
)
{
PWCHAR FileNameCopy, ParentFileName;
NTSTATUS Status;
PBL_DEVICE_ENTRY DeviceEntry;
PBL_FILE_SYSTEM_ENTRY FileSystem;
ULONG FileId, CheckFlags;
PBL_FILE_ENTRY DirectoryEntry, FileEntry;
PLIST_ENTRY NextEntry, ListHead;
/* Preinitialize variables for failure */
DirectoryEntry = NULL;
FileNameCopy = NULL;
ParentFileName = NULL;
Status = STATUS_SUCCESS;
/* Bail out if the device ID is invalid */
if (DmTableEntries <= DeviceId)
{
return STATUS_ACCESS_DENIED;
}
/* Bail out if there's no device entry */
DeviceEntry = DmDeviceTable[DeviceId];
if (!DeviceEntry)
{
return STATUS_ACCESS_DENIED;
}
/* Read access is always required for touching the device */
CheckFlags = Flags | BL_FILE_READ_ACCESS;
/* Check if the device is granting us read access */
if ((CheckFlags & BL_FILE_READ_ACCESS) &&
(!(DeviceEntry->Flags & BL_DEVICE_ENTRY_OPENED) ||
!(DeviceEntry->Flags & BL_DEVICE_ENTRY_READ_ACCESS)))
{
EfiPrintf(L"Access denied\r\n");
return STATUS_ACCESS_DENIED;
}
/* Check if the device is granting us write access */
if ((CheckFlags & BL_FILE_WRITE_ACCESS) &&
(!(DeviceEntry->Flags & BL_DEVICE_ENTRY_OPENED) ||
!(DeviceEntry->Flags & BL_DEVICE_ENTRY_WRITE_ACCESS)))
{
EfiPrintf(L"Access denied2\r\n");
return STATUS_ACCESS_DENIED;
}
/* Check if we already have this file open */
FileEntry = (PBL_FILE_ENTRY )BlTblFindEntry(FileTable,
FileEntries,
&FileId,
CompareRoutine,
&DeviceId,
FileName,
&Flags,
&Unknown);
if (FileEntry)
{
EfiPrintf(L"Entry exists: %p\n", FileEntry);
goto FileOpened;
}
/* Check if we are opening the root drive or an actual file/directory */
if ((*FileName != OBJ_NAME_PATH_SEPARATOR) || (FileName[1]))
{
/* Get the name of the directory */
ParentFileName = FileIoCopyParentDirectoryPath(FileName);
if (!ParentFileName)
{
Status = STATUS_NO_MEMORY;
goto Quickie;
}
/* Open it */
Status = FileIoOpen(DeviceId,
ParentFileName,
BL_FILE_READ_ACCESS | BL_DIRECTORY_ACCESS,
Unknown,
FileTableCompareWithSubsetAttributes,
&DirectoryEntry);
if (!NT_SUCCESS(Status))
{
goto Quickie;
}
/* Now get the the file name itself */
FileNameCopy = FileIoCopyFileName(FileName);
if (!FileNameCopy)
{
Status = STATUS_NO_MEMORY;
goto Quickie;
}
/* Open it */
Status = DirectoryEntry->Callbacks.Open(DirectoryEntry,
FileNameCopy,
Flags,
&FileEntry);
}
else
{
/* We're opening the root, scan through all the file systems */
Status = STATUS_UNSUCCESSFUL;
ListHead = &RegisteredFileSystems;
NextEntry = ListHead->Flink;
while (NextEntry != ListHead)
{
/* Try to mount this one */
FileSystem = CONTAINING_RECORD(NextEntry, BL_FILE_SYSTEM_ENTRY, ListEntry);
Status = FileSystem->MountCallback(DeviceId, Unknown, &FileEntry);
if (NT_SUCCESS(Status))
{
/* Mount successful */
break;
}
/* Try the next file system */
NextEntry = NextEntry->Flink;
}
/* Nothing to free on this path */
FileNameCopy = NULL;
}
/* Handle failure */
if (!NT_SUCCESS(Status))
{
EfiPrintf(L"Could not open file!: %lx\r\n", Status);
goto Quickie;
}
/* Save the unknown */
FileEntry->Unknown = Unknown;
/* Convert open flags into entry flags */
if (Flags & BL_FILE_READ_ACCESS)
{
FileEntry->Flags |= BL_FILE_ENTRY_READ_ACCESS;
}
if (Flags & BL_FILE_WRITE_ACCESS)
{
FileEntry->Flags |= BL_FILE_ENTRY_WRITE_ACCESS;
}
/* Save the file into the file table */
Status = BlTblSetEntry(&FileTable,
&FileEntries,
(PVOID)FileEntry,
&FileId,
FileTablePurgeEntry);
if (!NT_SUCCESS(Status))
{
/* Close it if that failed */
FileEntry->Callbacks.Close(FileEntry);
goto Quickie;
}
/* Add a reference on the device, and save our file ID */
++DeviceEntry->ReferenceCount;
Status = STATUS_SUCCESS;
FileEntry->FileId = FileId;
EfiPrintf(L"File %s opened with ID: %lx\r\n", FileEntry->FilePath, FileId);
FileOpened:
/* Add a reference to the file entry, and see if this is the first one */
if (++FileEntry->ReferenceCount == 1)
{
/* Reset unknowns */
FileEntry->TotalBytesRead = 0;
FileEntry->Unknown2 = 0;
}
/* Set the file as opened */
FileEntry->Flags |= BL_FILE_ENTRY_OPENED;
/* Not sure what this flag does */
if (Flags & BL_UNKNOWN_ACCESS)
{
FileEntry->Flags |= BL_FILE_ENTRY_UNKNOWN_ACCESS;
}
/* If the caller wanted the entry back, return it */
if (NewFileEntry)
{
*NewFileEntry = FileEntry;
}
Quickie:
/* Close the parent */
if (DirectoryEntry)
{
BlFileClose(DirectoryEntry->FileId);
}
/* Free the parent name copy */
if (ParentFileName)
{
BlMmFreeHeap(ParentFileName);
}
/* Free the file name copy */
if (FileNameCopy)
{
BlMmFreeHeap(FileNameCopy);
}
/* Return back to caller */
return Status;
}
