[PATCH] fs/sysv/: doc cleanup
Remove two different changelog files from fs/sysv/ and merges the INTRO file into Documentation/filesystems/sysv-fs.txt Signed-off-by: Adrian Bunk <bunk@stusta.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Adrian Bunk
committed by
Linus Torvalds
Linus Torvalds
parent
f1a60dbf68
commit
3982cd99c3
@@ -1,11 +1,8 @@
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This is the implementation of the SystemV/Coherent filesystem for Linux.
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It implements all of
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It implements all of
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- Xenix FS,
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- Xenix FS,
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- SystemV/386 FS,
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- SystemV/386 FS,
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- Coherent FS.
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- Coherent FS.
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This is version beta 4.
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To install:
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To install:
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* Answer the 'System V and Coherent filesystem support' question with 'y'
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* Answer the 'System V and Coherent filesystem support' question with 'y'
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when configuring the kernel.
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when configuring the kernel.
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@@ -28,11 +25,173 @@ Bugs in the present implementation:
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for this FS on hard disk yet.
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for this FS on hard disk yet.
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Please report any bugs and suggestions to
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These filesystems are rather similar. Here is a comparison with Minix FS:
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Bruno Haible <haible@ma2s2.mathematik.uni-karlsruhe.de>
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Pascal Haible <haible@izfm.uni-stuttgart.de>
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Krzysztof G. Baranowski <kgb@manjak.knm.org.pl>
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Bruno Haible
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* Linux fdisk reports on partitions
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<haible@ma2s2.mathematik.uni-karlsruhe.de>
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- Minix FS 0x81 Linux/Minix
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- Xenix FS ??
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- SystemV FS ??
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- Coherent FS 0x08 AIX bootable
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* Size of a block or zone (data allocation unit on disk)
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- Minix FS 1024
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- Xenix FS 1024 (also 512 ??)
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- SystemV FS 1024 (also 512 and 2048)
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- Coherent FS 512
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* General layout: all have one boot block, one super block and
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separate areas for inodes and for directories/data.
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On SystemV Release 2 FS (e.g. Microport) the first track is reserved and
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all the block numbers (including the super block) are offset by one track.
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* Byte ordering of "short" (16 bit entities) on disk:
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- Minix FS little endian 0 1
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- Xenix FS little endian 0 1
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- SystemV FS little endian 0 1
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- Coherent FS little endian 0 1
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Of course, this affects only the file system, not the data of files on it!
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* Byte ordering of "long" (32 bit entities) on disk:
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- Minix FS little endian 0 1 2 3
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- Xenix FS little endian 0 1 2 3
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- SystemV FS little endian 0 1 2 3
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- Coherent FS PDP-11 2 3 0 1
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Of course, this affects only the file system, not the data of files on it!
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* Inode on disk: "short", 0 means non-existent, the root dir ino is:
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- Minix FS 1
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- Xenix FS, SystemV FS, Coherent FS 2
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* Maximum number of hard links to a file:
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- Minix FS 250
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- Xenix FS ??
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- SystemV FS ??
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- Coherent FS >=10000
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* Free inode management:
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- Minix FS a bitmap
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- Xenix FS, SystemV FS, Coherent FS
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There is a cache of a certain number of free inodes in the super-block.
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When it is exhausted, new free inodes are found using a linear search.
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* Free block management:
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- Minix FS a bitmap
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- Xenix FS, SystemV FS, Coherent FS
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Free blocks are organized in a "free list". Maybe a misleading term,
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since it is not true that every free block contains a pointer to
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the next free block. Rather, the free blocks are organized in chunks
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of limited size, and every now and then a free block contains pointers
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to the free blocks pertaining to the next chunk; the first of these
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contains pointers and so on. The list terminates with a "block number"
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0 on Xenix FS and SystemV FS, with a block zeroed out on Coherent FS.
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* Super-block location:
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- Minix FS block 1 = bytes 1024..2047
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- Xenix FS block 1 = bytes 1024..2047
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- SystemV FS bytes 512..1023
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- Coherent FS block 1 = bytes 512..1023
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* Super-block layout:
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- Minix FS
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unsigned short s_ninodes;
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unsigned short s_nzones;
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unsigned short s_imap_blocks;
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unsigned short s_zmap_blocks;
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unsigned short s_firstdatazone;
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unsigned short s_log_zone_size;
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unsigned long s_max_size;
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unsigned short s_magic;
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- Xenix FS, SystemV FS, Coherent FS
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unsigned short s_firstdatazone;
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unsigned long s_nzones;
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unsigned short s_fzone_count;
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unsigned long s_fzones[NICFREE];
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unsigned short s_finode_count;
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unsigned short s_finodes[NICINOD];
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char s_flock;
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char s_ilock;
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char s_modified;
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char s_rdonly;
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unsigned long s_time;
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short s_dinfo[4]; -- SystemV FS only
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unsigned long s_free_zones;
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unsigned short s_free_inodes;
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short s_dinfo[4]; -- Xenix FS only
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unsigned short s_interleave_m,s_interleave_n; -- Coherent FS only
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char s_fname[6];
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char s_fpack[6];
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then they differ considerably:
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Xenix FS
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char s_clean;
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char s_fill[371];
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long s_magic;
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long s_type;
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SystemV FS
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long s_fill[12 or 14];
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long s_state;
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long s_magic;
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long s_type;
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Coherent FS
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unsigned long s_unique;
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Note that Coherent FS has no magic.
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* Inode layout:
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- Minix FS
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unsigned short i_mode;
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unsigned short i_uid;
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unsigned long i_size;
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unsigned long i_time;
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unsigned char i_gid;
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unsigned char i_nlinks;
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unsigned short i_zone[7+1+1];
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- Xenix FS, SystemV FS, Coherent FS
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unsigned short i_mode;
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unsigned short i_nlink;
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unsigned short i_uid;
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unsigned short i_gid;
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unsigned long i_size;
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unsigned char i_zone[3*(10+1+1+1)];
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unsigned long i_atime;
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unsigned long i_mtime;
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unsigned long i_ctime;
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* Regular file data blocks are organized as
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- Minix FS
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7 direct blocks
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1 indirect block (pointers to blocks)
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1 double-indirect block (pointer to pointers to blocks)
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- Xenix FS, SystemV FS, Coherent FS
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10 direct blocks
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1 indirect block (pointers to blocks)
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1 double-indirect block (pointer to pointers to blocks)
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1 triple-indirect block (pointer to pointers to pointers to blocks)
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* Inode size, inodes per block
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- Minix FS 32 32
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- Xenix FS 64 16
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- SystemV FS 64 16
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- Coherent FS 64 8
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* Directory entry on disk
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- Minix FS
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unsigned short inode;
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char name[14/30];
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- Xenix FS, SystemV FS, Coherent FS
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unsigned short inode;
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char name[14];
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* Dir entry size, dir entries per block
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- Minix FS 16/32 64/32
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- Xenix FS 16 64
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- SystemV FS 16 64
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- Coherent FS 16 32
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* How to implement symbolic links such that the host fsck doesn't scream:
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- Minix FS normal
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- Xenix FS kludge: as regular files with chmod 1000
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- SystemV FS ??
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- Coherent FS kludge: as regular files with chmod 1000
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Notation: We often speak of a "block" but mean a zone (the allocation unit)
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and not the disk driver's notion of "block".
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@@ -1,60 +0,0 @@
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Mon, 15 Dec 1997 Krzysztof G. Baranowski <kgb@manjak.knm.org.pl>
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* namei.c: struct sysv_dir_inode_operations updated to use dentries.
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Fri, 23 Jan 1998 Krzysztof G. Baranowski <kgb@manjak.knm.org.pl>
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* inode.c: corrected 1 track offset setting (in sb->sv_block_base).
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Originally it was overridden (by setting to zero)
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in detected_[xenix,sysv4,sysv2,coherent]. Thanks
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to Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
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for identifying the problem.
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Tue, 27 Jan 1998 Krzysztof G. Baranowski <kgb@manjak.knm.org.pl>
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* inode.c: added 2048-byte block support to SystemV FS.
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Merged detected_bs[512,1024,2048]() into one function:
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void detected_bs (u_char type, struct super_block *sb).
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Thanks to Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
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for the patch.
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Wed, 4 Feb 1998 Krzysztof G. Baranowski <kgb@manjak.knm.org.pl>
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* namei.c: removed static subdir(); is_subdir() from dcache.c
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is used instead. Cosmetic changes.
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Thu, 3 Dec 1998 Al Viro (viro@parcelfarce.linux.theplanet.co.uk)
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* namei.c (sysv_rmdir):
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Bugectomy: old check for victim being busy
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(inode->i_count) wasn't replaced (with checking
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dentry->d_count) and escaped Linus in the last round
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of changes. Shot and buried.
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Wed, 9 Dec 1998 AV
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* namei.c (do_sysv_rename):
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Fixed incorrect check for other owners + race.
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Removed checks that went to VFS.
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* namei.c (sysv_unlink):
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Removed checks that went to VFS.
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Thu, 10 Dec 1998 AV
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* namei.c (do_mknod):
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Removed dead code - mknod is never asked to
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create a symlink or directory. Incidentially,
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it wouldn't do it right if it would be called.
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Sat, 26 Dec 1998 KGB
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* inode.c (detect_sysv4):
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Added detection of expanded s_type field (0x10,
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0x20 and 0x30). Forced read-only access in this case.
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Sun, 21 Mar 1999 AV
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* namei.c (sysv_link):
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Fixed i_count usage that resulted in dcache corruption.
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* inode.c:
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Filled ->delete_inode() method with sysv_delete_inode().
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sysv_put_inode() is gone, as it tried to do ->delete_
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_inode()'s job.
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* ialloc.c: (sysv_free_inode):
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Fixed race.
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Sun, 30 Apr 1999 AV
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* namei.c (sysv_mknod):
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Removed dead code (S_IFREG case is now passed to
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->create() by VFS).
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@@ -1,106 +0,0 @@
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Thu Feb 14 2002 Andrew Morton <akpm@zip.com.au>
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* dir_commit_chunk(): call writeout_one_page() as well as
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waitfor_one_page() for IS_SYNC directories, so that we
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actually do sync the directory. (forward-port from 2.4).
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Thu Feb 7 2002 Alexander Viro <viro@parcelfarce.linux.theplanet.co.uk>
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* super.c: switched to ->get_sb()
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* ChangeLog: fixed dates ;-)
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2002-01-24 David S. Miller <davem@redhat.com>
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* inode.c: Include linux/init.h
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Mon Jan 21 2002 Alexander Viro <viro@parcelfarce.linux.theplanet.co.uk>
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* ialloc.c (sysv_new_inode): zero SYSV_I(inode)->i_data out.
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* i_vnode renamed to vfs_inode. Sorry, but let's keep that
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consistent.
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Sat Jan 19 2002 Christoph Hellwig <hch@infradead.org>
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* include/linux/sysv_fs.h (SYSV_I): Get fs-private inode data using
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list_entry() instead of inode->u.
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* include/linux/sysv_fs_i.h: Add 'struct inode i_vnode' field to
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sysv_inode_info structure.
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* inode.c: Include <linux/slab.h>, implement alloc_inode/destroy_inode
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sop methods, add infrastructure for per-fs inode slab cache.
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* super.c (init_sysv_fs): Initialize inode cache, recover properly
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in the case of failed register_filesystem for V7.
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(exit_sysv_fs): Destroy inode cache.
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Sat Jan 19 2002 Christoph Hellwig <hch@infradead.org>
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* include/linux/sysv_fs.h: Include <linux/sysv_fs_i.h>, declare SYSV_I().
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* dir.c (sysv_find_entry): Use SYSV_I() instead of ->u.sysv_i to
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access fs-private inode data.
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* ialloc.c (sysv_new_inode): Likewise.
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* inode.c (sysv_read_inode): Likewise.
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(sysv_update_inode): Likewise.
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* itree.c (get_branch): Likewise.
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(sysv_truncate): Likewise.
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* symlink.c (sysv_readlink): Likewise.
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(sysv_follow_link): Likewise.
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Fri Jan 4 2002 Alexander Viro <viro@parcelfarce.linux.theplanet.co.uk>
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* ialloc.c (sysv_free_inode): Use sb->s_id instead of bdevname().
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* inode.c (sysv_read_inode): Likewise.
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(sysv_update_inode): Likewise.
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(sysv_sync_inode): Likewise.
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* super.c (detect_sysv): Likewise.
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(complete_read_super): Likewise.
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(sysv_read_super): Likewise.
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(v7_read_super): Likewise.
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Sun Dec 30 2001 Manfred Spraul <manfred@colorfullife.com>
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* dir.c (dir_commit_chunk): Do not set dir->i_version.
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(sysv_readdir): Likewise.
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Thu Dec 27 2001 Alexander Viro <viro@parcelfarce.linux.theplanet.co.uk>
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* itree.c (get_block): Use map_bh() to fill out bh_result.
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Tue Dec 25 2001 Alexander Viro <viro@parcelfarce.linux.theplanet.co.uk>
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* super.c (sysv_read_super): Use sb_set_blocksize() to set blocksize.
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(v7_read_super): Likewise.
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Tue Nov 27 2001 Alexander Viro <viro@parcelfarce.linux.theplanet.co.uk>
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* itree.c (get_block): Change type for iblock argument to sector_t.
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* super.c (sysv_read_super): Set s_blocksize early.
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(v7_read_super): Likewise.
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* balloc.c (sysv_new_block): Use sb_bread(). instead of bread().
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(sysv_count_free_blocks): Likewise.
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* ialloc.c (sysv_raw_inode): Likewise.
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* itree.c (get_branch): Likewise.
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(free_branches): Likewise.
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* super.c (sysv_read_super): Likewise.
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(v7_read_super): Likewise.
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Sat Dec 15 2001 Christoph Hellwig <hch@infradead.org>
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* inode.c (sysv_read_inode): Mark inode as bad in case of failure.
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* super.c (complete_read_super): Check for bad root inode.
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Wed Nov 21 2001 Andrew Morton <andrewm@uow.edu.au>
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* file.c (sysv_sync_file): Call fsync_inode_data_buffers.
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Fri Oct 26 2001 Christoph Hellwig <hch@infradead.org>
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* dir.c, ialloc.c, namei.c, include/linux/sysv_fs_i.h:
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Implement per-Inode lookup offset cache.
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Modelled after Ted's ext2 patch.
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|
||||||
Fri Oct 26 2001 Christoph Hellwig <hch@infradead.org>
|
|
||||||
|
|
||||||
* inode.c, super.c, include/linux/sysv_fs.h,
|
|
||||||
include/linux/sysv_fs_sb.h:
|
|
||||||
Remove symlink faking. Noone really wants to use these as
|
|
||||||
linux filesystems and native OSes don't support it anyway.
|
|
||||||
|
|
||||||
|
|
||||||
182
fs/sysv/INTRO
182
fs/sysv/INTRO
@@ -1,182 +0,0 @@
|
|||||||
This is the implementation of the SystemV/Coherent filesystem for Linux.
|
|
||||||
It grew out of separate filesystem implementations
|
|
||||||
|
|
||||||
Xenix FS Doug Evans <dje@cygnus.com> June 1992
|
|
||||||
SystemV FS Paul B. Monday <pmonday@eecs.wsu.edu> March-June 1993
|
|
||||||
Coherent FS B. Haible <haible@ma2s2.mathematik.uni-karlsruhe.de> June 1993
|
|
||||||
|
|
||||||
and was merged together in July 1993.
|
|
||||||
|
|
||||||
These filesystems are rather similar. Here is a comparison with Minix FS:
|
|
||||||
|
|
||||||
* Linux fdisk reports on partitions
|
|
||||||
- Minix FS 0x81 Linux/Minix
|
|
||||||
- Xenix FS ??
|
|
||||||
- SystemV FS ??
|
|
||||||
- Coherent FS 0x08 AIX bootable
|
|
||||||
|
|
||||||
* Size of a block or zone (data allocation unit on disk)
|
|
||||||
- Minix FS 1024
|
|
||||||
- Xenix FS 1024 (also 512 ??)
|
|
||||||
- SystemV FS 1024 (also 512 and 2048)
|
|
||||||
- Coherent FS 512
|
|
||||||
|
|
||||||
* General layout: all have one boot block, one super block and
|
|
||||||
separate areas for inodes and for directories/data.
|
|
||||||
On SystemV Release 2 FS (e.g. Microport) the first track is reserved and
|
|
||||||
all the block numbers (including the super block) are offset by one track.
|
|
||||||
|
|
||||||
* Byte ordering of "short" (16 bit entities) on disk:
|
|
||||||
- Minix FS little endian 0 1
|
|
||||||
- Xenix FS little endian 0 1
|
|
||||||
- SystemV FS little endian 0 1
|
|
||||||
- Coherent FS little endian 0 1
|
|
||||||
Of course, this affects only the file system, not the data of files on it!
|
|
||||||
|
|
||||||
* Byte ordering of "long" (32 bit entities) on disk:
|
|
||||||
- Minix FS little endian 0 1 2 3
|
|
||||||
- Xenix FS little endian 0 1 2 3
|
|
||||||
- SystemV FS little endian 0 1 2 3
|
|
||||||
- Coherent FS PDP-11 2 3 0 1
|
|
||||||
Of course, this affects only the file system, not the data of files on it!
|
|
||||||
|
|
||||||
* Inode on disk: "short", 0 means non-existent, the root dir ino is:
|
|
||||||
- Minix FS 1
|
|
||||||
- Xenix FS, SystemV FS, Coherent FS 2
|
|
||||||
|
|
||||||
* Maximum number of hard links to a file:
|
|
||||||
- Minix FS 250
|
|
||||||
- Xenix FS ??
|
|
||||||
- SystemV FS ??
|
|
||||||
- Coherent FS >=10000
|
|
||||||
|
|
||||||
* Free inode management:
|
|
||||||
- Minix FS a bitmap
|
|
||||||
- Xenix FS, SystemV FS, Coherent FS
|
|
||||||
There is a cache of a certain number of free inodes in the super-block.
|
|
||||||
When it is exhausted, new free inodes are found using a linear search.
|
|
||||||
|
|
||||||
* Free block management:
|
|
||||||
- Minix FS a bitmap
|
|
||||||
- Xenix FS, SystemV FS, Coherent FS
|
|
||||||
Free blocks are organized in a "free list". Maybe a misleading term,
|
|
||||||
since it is not true that every free block contains a pointer to
|
|
||||||
the next free block. Rather, the free blocks are organized in chunks
|
|
||||||
of limited size, and every now and then a free block contains pointers
|
|
||||||
to the free blocks pertaining to the next chunk; the first of these
|
|
||||||
contains pointers and so on. The list terminates with a "block number"
|
|
||||||
0 on Xenix FS and SystemV FS, with a block zeroed out on Coherent FS.
|
|
||||||
|
|
||||||
* Super-block location:
|
|
||||||
- Minix FS block 1 = bytes 1024..2047
|
|
||||||
- Xenix FS block 1 = bytes 1024..2047
|
|
||||||
- SystemV FS bytes 512..1023
|
|
||||||
- Coherent FS block 1 = bytes 512..1023
|
|
||||||
|
|
||||||
* Super-block layout:
|
|
||||||
- Minix FS
|
|
||||||
unsigned short s_ninodes;
|
|
||||||
unsigned short s_nzones;
|
|
||||||
unsigned short s_imap_blocks;
|
|
||||||
unsigned short s_zmap_blocks;
|
|
||||||
unsigned short s_firstdatazone;
|
|
||||||
unsigned short s_log_zone_size;
|
|
||||||
unsigned long s_max_size;
|
|
||||||
unsigned short s_magic;
|
|
||||||
- Xenix FS, SystemV FS, Coherent FS
|
|
||||||
unsigned short s_firstdatazone;
|
|
||||||
unsigned long s_nzones;
|
|
||||||
unsigned short s_fzone_count;
|
|
||||||
unsigned long s_fzones[NICFREE];
|
|
||||||
unsigned short s_finode_count;
|
|
||||||
unsigned short s_finodes[NICINOD];
|
|
||||||
char s_flock;
|
|
||||||
char s_ilock;
|
|
||||||
char s_modified;
|
|
||||||
char s_rdonly;
|
|
||||||
unsigned long s_time;
|
|
||||||
short s_dinfo[4]; -- SystemV FS only
|
|
||||||
unsigned long s_free_zones;
|
|
||||||
unsigned short s_free_inodes;
|
|
||||||
short s_dinfo[4]; -- Xenix FS only
|
|
||||||
unsigned short s_interleave_m,s_interleave_n; -- Coherent FS only
|
|
||||||
char s_fname[6];
|
|
||||||
char s_fpack[6];
|
|
||||||
then they differ considerably:
|
|
||||||
Xenix FS
|
|
||||||
char s_clean;
|
|
||||||
char s_fill[371];
|
|
||||||
long s_magic;
|
|
||||||
long s_type;
|
|
||||||
SystemV FS
|
|
||||||
long s_fill[12 or 14];
|
|
||||||
long s_state;
|
|
||||||
long s_magic;
|
|
||||||
long s_type;
|
|
||||||
Coherent FS
|
|
||||||
unsigned long s_unique;
|
|
||||||
Note that Coherent FS has no magic.
|
|
||||||
|
|
||||||
* Inode layout:
|
|
||||||
- Minix FS
|
|
||||||
unsigned short i_mode;
|
|
||||||
unsigned short i_uid;
|
|
||||||
unsigned long i_size;
|
|
||||||
unsigned long i_time;
|
|
||||||
unsigned char i_gid;
|
|
||||||
unsigned char i_nlinks;
|
|
||||||
unsigned short i_zone[7+1+1];
|
|
||||||
- Xenix FS, SystemV FS, Coherent FS
|
|
||||||
unsigned short i_mode;
|
|
||||||
unsigned short i_nlink;
|
|
||||||
unsigned short i_uid;
|
|
||||||
unsigned short i_gid;
|
|
||||||
unsigned long i_size;
|
|
||||||
unsigned char i_zone[3*(10+1+1+1)];
|
|
||||||
unsigned long i_atime;
|
|
||||||
unsigned long i_mtime;
|
|
||||||
unsigned long i_ctime;
|
|
||||||
|
|
||||||
* Regular file data blocks are organized as
|
|
||||||
- Minix FS
|
|
||||||
7 direct blocks
|
|
||||||
1 indirect block (pointers to blocks)
|
|
||||||
1 double-indirect block (pointer to pointers to blocks)
|
|
||||||
- Xenix FS, SystemV FS, Coherent FS
|
|
||||||
10 direct blocks
|
|
||||||
1 indirect block (pointers to blocks)
|
|
||||||
1 double-indirect block (pointer to pointers to blocks)
|
|
||||||
1 triple-indirect block (pointer to pointers to pointers to blocks)
|
|
||||||
|
|
||||||
* Inode size, inodes per block
|
|
||||||
- Minix FS 32 32
|
|
||||||
- Xenix FS 64 16
|
|
||||||
- SystemV FS 64 16
|
|
||||||
- Coherent FS 64 8
|
|
||||||
|
|
||||||
* Directory entry on disk
|
|
||||||
- Minix FS
|
|
||||||
unsigned short inode;
|
|
||||||
char name[14/30];
|
|
||||||
- Xenix FS, SystemV FS, Coherent FS
|
|
||||||
unsigned short inode;
|
|
||||||
char name[14];
|
|
||||||
|
|
||||||
* Dir entry size, dir entries per block
|
|
||||||
- Minix FS 16/32 64/32
|
|
||||||
- Xenix FS 16 64
|
|
||||||
- SystemV FS 16 64
|
|
||||||
- Coherent FS 16 32
|
|
||||||
|
|
||||||
* How to implement symbolic links such that the host fsck doesn't scream:
|
|
||||||
- Minix FS normal
|
|
||||||
- Xenix FS kludge: as regular files with chmod 1000
|
|
||||||
- SystemV FS ??
|
|
||||||
- Coherent FS kludge: as regular files with chmod 1000
|
|
||||||
|
|
||||||
|
|
||||||
Notation: We often speak of a "block" but mean a zone (the allocation unit)
|
|
||||||
and not the disk driver's notion of "block".
|
|
||||||
|
|
||||||
|
|
||||||
Bruno Haible <haible@ma2s2.mathematik.uni-karlsruhe.de>
|
|
||||||
Reference in New Issue
Block a user