-- VMMgr>Hierarchy.mesa (last edited by Knutsen on November 8, 1979 8:47 AM)

-- Definitions:
-- A handle is strict if handle.page is the first page of a space or swap unit.
-- A handle is relaxed if handle.page is any other page of a space or swap unit.

DIRECTORY

CachedSpace: FROM "CachedSpace" USING [Desc, Handle],

VM: FROM "VM" USING [Interval, PageCount];

Hierarchy: DEFINITIONS =

BEGIN

Delete: PROCEDURE [handle: CachedSpace.Handle];

FindFirstWithin: PROCEDURE [handle: CachedSpace.Handle, count: VM.PageCount] RETURNS [CachedSpace.Handle];

-- Returns first "n’th cousin" starting within count pages of beginning of space, handleNull if none.

GetDescriptor: PROCEDURE [pDescResult: POINTER TO CachedSpace.Desc, handle: CachedSpace.Handle]
RETURNS [validSpace: BOOLEAN, validSwapUnit: BOOLEAN];

-- Various argument handles produce various results, as follows:

--handlepDescResult↑ validSpacevalidSwapUnit

--strict space handledesc of space, state~=missingTRUEFALSE

--relaxed space handledesc of space, state~=missingFALSEFALSE

--strict swap unit handledesc of parent space, state~=missingFALSETRUE

--relaxed swap unit handledesc of parent space, state~=missingFALSEFALSE

--invaliddummy desc, state=missingFALSEFALSE

GetInterval: PROCEDURE [handle: CachedSpace.Handle] RETURNS [validSpace: BOOLEAN, validSwapUnit: BOOLEAN, interval: VM.Interval];

-- Various argument handles produce various results, as follows:

--handleinterval validSpacevalidSwapUnit

--strict space handleinterval of spaceTRUEFALSE

--relaxed space handleinterval of spaceFALSEFALSE

--strict swap unit handleinterval of swap unitFALSETRUE

--relaxed swap unit handleinterval of swap unitFALSEFALSE

--invalid[0,0]FALSEFALSE

ValidSpaceOrSwapUnit: PROCEDURE [handle: CachedSpace.Handle] RETURNS [BOOLEAN];

-- Returns TRUE iff handle is a strict space handle or a strict swap unit handle.

Insert: PROCEDURE [handle: CachedSpace.Handle, count: VM.PageCount];

-- Sets pinned←FALSE, state←unmapped.

Touch: PROCEDURE [handle: CachedSpace.Handle];

-- May raise NotFound.

Update: PROCEDURE [pDesc: POINTER TO CachedSpace.Desc];

-- Updates cached copy (and sets dDirty←TRUE) if one exists; else updates in stree.

NotFound: ERROR;

END.

Notes

Replace GetDescriptor, GetInterval, GetState by GetShort (3 words) and GetLong (11 words)

LOG

Time: April 25, 1978 5:20 PMBy: McJonesAction: Created file

Time: September 10, 1978 1:31 PMBy: McJonesAction: Merged ValidHandle with GetXXX, etc.

Time: November 8, 1979 8:48 AMBy: KnutsenAction: Procedures return validSpace and validSwapUnit instead of validHandle. GetState replaced by ValidSpaceOrSwapUnit.