// IFS.decl - Commonly-needed runtime structures // This is presently a hodge-podge. It is due for reorganization. // Copyright Xerox Corporation 1979, 1980, 1981 // Last modified November 14, 1981 10:34 AM by Taft //---------------------------------------------------------------------------- manifest // file system declarations //---------------------------------------------------------------------------- [ nDrives = 8 // maximum number of drives nDisks = 2*nDrives // maximum number of 'disk' objects ifsSwapPages = 150 // pages to preallocate for IFS.Swap ifsErrorPages = 10 // pages to preallocate for IFS.Errors ifsSymsPages = 50 // pages to preallocate for IFS.Syms systemInfoPages = 10 // pages to preallocate for Info logStdPageLength = 10 // log standard page length -- // unit of core page allocation // Error codes returned by OpenIFS ecDupLUnit = 18 // Duplicate logical unit ecNoLUnit0 = 19 // No logical unit 0 ecNumUnits = 20 // can't find numUnits packs ec2LUnit0s = 21 // two logical unit 0s with same id ecNoIFSDir = 22 // can't open ifs.dir // some other useful error codes ecDiabloFile = 6 // OpenFile (Alto OS version) failed ecTridentFile = 7 // OpenFile (Alto OS version) failed ] //---------------------------------------------------------------------------- structure Lock: //---------------------------------------------------------------------------- [ ctx word // last context to set this lock count word // 0 means not locked // + read lock count, -1 write locked ] manifest lenLock = size Lock/16 //---------------------------------------------------------------------------- structure ECB: // Event Control Block //---------------------------------------------------------------------------- [ link word timer word // 5.46 minutes (32767 x 10 ms) max proc word // called when timer has expired ] manifest lenECB = size ECB/16 //---------------------------------------------------------------------------- structure DTE: // Drive Table Entry //---------------------------------------------------------------------------- [ ifs word // -> IFS structure. 0 => not part of an IFS disk^0,1 word // -> TFSDSK structure(s) for this drive ] //---------------------------------------------------------------------------- structure DriveTab^0, nDrives-1 @DTE // Drive Table //---------------------------------------------------------------------------- manifest lenDriveTab = size DriveTab/16 //---------------------------------------------------------------------------- structure IFS: // Interim File System //---------------------------------------------------------------------------- [ link word // IFSs are linked together on fsQ // configuration information lpdt^0,nDisks-1 word // logical to physical disk table logPageLength word // size of pages in this file system pageLength word numUnits word // # of units in this ifs type word // primary, backup etc id word // -> id string name word // -> name string created word 2 // unique id for file system // directory information dirLock @Lock // lock for IFS.Dir dirLockConflict word // true if lock conflict has occurred dirVersion word // directory version number, incremented // each time the directory is modified dirBTree word // -> B-Tree structure for IFS.Dir oft word // -> Open File Table ] manifest lenIFS = size IFS/16 //---------------------------------------------------------------------------- structure CPar: // Parameters passed to CreateIFS //---------------------------------------------------------------------------- [ id word // -> id string name word // -> name string type word // ifs type numUnits word // number of logical units lpMap^0,nDrives-1 word // log-phys map. Entries are PUnit #s blank word nDrives // reserved for "fake" units (see CreateIFS) dirSize word // number of pages to preallocate for IFS.dir ] manifest lenCPar = size CPar/16 // everyone needs this! but it's also defined in Pup1.decl. compileif newname String then [ structure String: [ length byte; char^1,1 byte ] ]