-- LabelTransfer.mesa (last edited by: Luniewski on: January 9, 1981 10:14 AM)

DIRECTORY

DiskChannel USING [Address, CompletionStatus, Drive],

Environment USING [PageNumber],

File USING [PageCount, PageNumber],

FileInternal USING [Descriptor, Operation, PageGroup],

PilotDisk USING [Label],

VolumeInternal USING [PageNumber];

LabelTransfer: DEFINITIONS =

BEGIN

Operation: TYPE = FileInternal.Operation[readLabel..writeLabelsAndData];

ReadLabel: PROCEDURE [
file: FileInternal.Descriptor,
filePage: File.PageNumber,
volumePage: VolumeInternal.PageNumber,
handleErrors: BOOLEAN ← TRUE]

RETURNS [label: PilotDisk.Label, status: DiskChannel.CompletionStatus];

ReadRootLabel: PROCEDURE [
drive: DiskChannel.Drive,
rootPage: VolumeInternal.PageNumber]
RETURNS [label: PilotDisk.Label, status: DiskChannel.CompletionStatus];

WriteLabels: PROCEDURE [
file: FileInternal.Descriptor,
pageGroup: FileInternal.PageGroup,
handleErrors: BOOLEAN ← TRUE]

RETURNS [status: DiskChannel.CompletionStatus];

VerifyLabels: PROCEDURE [
file: FileInternal.Descriptor,
pageGroup: FileInternal.PageGroup,
expectErrorAfterFirstPage: BOOLEAN ← FALSE,
handleErrors: BOOLEAN ← TRUE]
-- mainly for scavenger; TRUE inhibits low level retries if labels don’t match AFTER first page of run
RETURNS [countValid: File.PageCount, status: DiskChannel.CompletionStatus];

ReadLabelAndData: PROCEDURE [
file: FileInternal.Descriptor,
filePage: File.PageNumber,
volumePage: VolumeInternal.PageNumber,
memoryPage: Environment.PageNumber,
handleErrors: BOOLEAN ← TRUE]

RETURNS [label: PilotDisk.Label, status: DiskChannel.CompletionStatus];

WriteLabelAndData: PROCEDURE [
file: FileInternal.Descriptor,
filePage: File.PageNumber,
volumePage: VolumeInternal.PageNumber,
memoryPage: Environment.PageNumber,
bootChainLink: DiskChannel.Address ← NULL,
handleErrors: BOOLEAN ← TRUE]

RETURNS [status: DiskChannel.CompletionStatus];

LabelStatus: TYPE = {valid, invalid, diskError};

DiskStatusToLabelStatus: PROCEDURE [status: DiskChannel.CompletionStatus]

RETURNS [labelStatus: LabelStatus] = INLINE

{RETURN[SELECT status FROM

goodCompletion => valid,

hardwareError, notReady => diskError,

ENDCASE => invalid]};

END.

LOG

Time: June 15, 1978 11:03 PMBy: RedellAction: Create file

Time: March 13, 1979 7:28 PMBy: RedellAction: Add ReadRootLabel

Time: August 1, 1979 12:13 PMBy: RedellAction: Use FilePageLabel

Time: August 13, 1979 3:18 PMBy: RedellAction: Change WriteLabelAndData to do runs of pages with optional chaining; don’t loophole drive

Time: September 17, 1979 4:36 PMBy: ForrestAction: Add LabelStatus, and caused ReadRootLabel to return it. Should other label procs use this also?

Time: January 9, 1980 2:24 PMBy: GobbelAction: Add countValid to RETURNS of VerifyLabels

Time: August 14, 1980 9:50 AMBy: McJonesAction: WriteLabelsAndData=>WriteLabelAndData; FilePageLabel=>PilotDisk

Time: October 11, 1980 7:40 PMBy: ForrestAction: add crock (for scavenger) that causes VerifyLabels to not retry if at least the first page of the run is OK.

Time: January 9, 1981 10:14 AMBy: LuniewskiAction: Add option of not having lower levels handle disk errors and to return disk status instead (for Scavenger).