Author: wmb Date: 2010-01-10 11:49:32 +0100 (Sun, 10 Jan 2010) New Revision: 1657
Modified: ofw/fs/ext2fs/bitmap.fth ofw/fs/ext2fs/dir.fth ofw/fs/ext2fs/sb.fth Log: OLPC trac 9972 - fixed ext2 filesystem corruption that happened in certain cases. The problem was with the sparse superblock feature. You must not write backup copies of the superblock and group descriptors in every group when that feature is enabled.
Modified: ofw/fs/ext2fs/bitmap.fth =================================================================== --- ofw/fs/ext2fs/bitmap.fth 2010-01-09 08:12:32 UTC (rev 1656) +++ ofw/fs/ext2fs/bitmap.fth 2010-01-10 10:49:32 UTC (rev 1657) @@ -164,10 +164,19 @@ : update-gds ( -- ) gd-modified? if \ Copy group descriptors to backup locations + \ XXX if SPARSE_SUPER, then write only to groups 0,1, and powers of 3,5,7 + \ One way to find out, other than checking the numbers, is to inspect + \ the block bitmap number in the group descriptor. If it is larger than + \ the calculated block number, do the backup. #groups 1 do - 0 group-desc ( gd0-adr ) - i bpg * 2+ block ( gd0-adr gdn-adr ) - bsize move update ( ) + i bpg * 2+ ( possible-gn ) + dup i block-bitmap < if ( possible-gn ) + block ( gdn-adr ) + 0 group-desc ( gdn-adr gd0-adr ) + swap bsize move update ( ) + else ( possible-gn ) + drop ( ) + then ( ) loop false to gd-modified? update-sb
Modified: ofw/fs/ext2fs/dir.fth =================================================================== --- ofw/fs/ext2fs/dir.fth 2010-01-09 08:12:32 UTC (rev 1656) +++ ofw/fs/ext2fs/dir.fth 2010-01-10 10:49:32 UTC (rev 1657) @@ -75,14 +75,13 @@ : +link-count ( increment -- ) link-count + link-count! ;
: new-inode ( mode -- inode# ) - alloc-inode set-inode - 0 +i /inode erase ( mode ) + alloc-inode set-inode ( mode ) \ alloc-inode erases the inode file-attr! ( ) time&date >unix-seconds ( time ) dup atime! ( time ) \ set access time dup ctime! ( time ) \ set creation time mtime! ( ) \ set modification time - 1 link-count! ( ) \ set links_count to 1 + 0 link-count! ( ) \ link count will be incremented by new-dirent inode# ( inode# ) ;
Modified: ofw/fs/ext2fs/sb.fth =================================================================== --- ofw/fs/ext2fs/sb.fth 2010-01-09 08:12:32 UTC (rev 1656) +++ ofw/fs/ext2fs/sb.fth 2010-01-10 10:49:32 UTC (rev 1657) @@ -28,6 +28,8 @@ : fpg ( -- n ) 9 +sbl ; \ h#2000 frags_per_group : ipg ( -- n ) 10 +sbl ; \ h#790 inodes_per_group : magic ( -- n ) 28 +sbw ; +: state@ ( -- n ) 29 +sbw ; \ for fsck: 0 for dirty, 1 for clean, 2 for known errors +: state! ( n -- ) super-block 29 wa+ short! ; : revlevel ( -- n ) 19 +sbl ; : /inode ( -- n ) revlevel 1 = if 44 +sbw else h# 80 then ; \ : bsize ( -- n )