linux/fs/jfs
Takashi Sato c4be0c1dc4 filesystem freeze: add error handling of write_super_lockfs/unlockfs
Currently, ext3 in mainline Linux doesn't have the freeze feature which
suspends write requests.  So, we cannot take a backup which keeps the
filesystem's consistency with the storage device's features (snapshot and
replication) while it is mounted.

In many case, a commercial filesystem (e.g.  VxFS) has the freeze feature
and it would be used to get the consistent backup.

If Linux's standard filesystem ext3 has the freeze feature, we can do it
without a commercial filesystem.

So I have implemented the ioctls of the freeze feature.
I think we can take the consistent backup with the following steps.
1. Freeze the filesystem with the freeze ioctl.
2. Separate the replication volume or create the snapshot
   with the storage device's feature.
3. Unfreeze the filesystem with the unfreeze ioctl.
4. Take the backup from the separated replication volume
   or the snapshot.

This patch:

VFS:
Changed the type of write_super_lockfs and unlockfs from "void"
to "int" so that they can return an error.
Rename write_super_lockfs and unlockfs of the super block operation
freeze_fs and unfreeze_fs to avoid a confusion.

ext3, ext4, xfs, gfs2, jfs:
Changed the type of write_super_lockfs and unlockfs from "void"
to "int" so that write_super_lockfs returns an error if needed,
and unlockfs always returns 0.

reiserfs:
Changed the type of write_super_lockfs and unlockfs from "void"
to "int" so that they always return 0 (success) to keep a current behavior.

Signed-off-by: Takashi Sato <t-sato@yk.jp.nec.com>
Signed-off-by: Masayuki Hamaguchi <m-hamaguchi@ys.jp.nec.com>
Cc: <xfs-masters@oss.sgi.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-09 16:54:42 -08:00
..
acl.c [PATCH] sanitize ->permission() prototype 2008-07-26 20:53:14 -04:00
endian24.h JFS: Whitespace cleanup and remove some dead code 2007-06-06 15:28:35 -05:00
file.c BKL-removal: Implement a compat_ioctl handler for JFS 2008-02-07 13:45:29 -06:00
inode.c jfs: ensure symlinks are NUL-terminated 2008-12-16 10:21:34 -06:00
ioctl.c [PATCH] r/o bind mounts: elevate write count for ioctls() 2008-04-19 00:29:24 -04:00
jfs_acl.h [PATCH] sanitize ->permission() prototype 2008-07-26 20:53:14 -04:00
jfs_btree.h JFS: White space cleanup 2006-10-02 09:55:27 -05:00
jfs_debug.c JFS: switch to seq_files 2008-05-13 08:22:10 -05:00
jfs_debug.h JFS: switch to seq_files 2008-05-13 08:22:10 -05:00
jfs_dinode.h BKL-removal: Implement a compat_ioctl handler for JFS 2008-02-07 13:45:29 -06:00
jfs_dmap.c jfs: le*_add_cpu conversion 2008-02-13 15:34:20 -06:00
jfs_dmap.h jfs: replace __inline with inline 2008-03-05 14:38:22 -06:00
jfs_dtree.c JFS: Remove defconfig ptr comparison to 0 2008-01-03 13:12:10 -06:00
jfs_dtree.h jfs: remove DIRENTSIZ 2008-06-10 15:12:58 -05:00
jfs_extent.c JFS: Whitespace cleanup and remove some dead code 2007-06-06 15:28:35 -05:00
jfs_extent.h JFS: White space cleanup 2006-10-02 09:55:27 -05:00
jfs_filsys.h JFS: Whitespace cleanup and remove some dead code 2007-06-06 15:28:35 -05:00
jfs_imap.c fix the treatment of jfs special inodes 2009-01-05 11:54:29 -05:00
jfs_imap.h JFS: Whitespace cleanup and remove some dead code 2007-06-06 15:28:35 -05:00
jfs_incore.h more low-hanging fruits - kernel, fs, lib signedness 2007-10-14 12:41:52 -07:00
jfs_inode.c nfsd race fixes: jfs 2008-12-31 18:07:44 -05:00
jfs_inode.h BKL-removal: Implement a compat_ioctl handler for JFS 2008-02-07 13:45:29 -06:00
jfs_lock.h JFS: use __set_current_state() 2007-04-26 07:30:29 -05:00
jfs_logmgr.c [PATCH] pass fmode_t to blkdev_put() 2008-10-21 07:48:58 -04:00
jfs_logmgr.h more low-hanging fruits - kernel, fs, lib signedness 2007-10-14 12:41:52 -07:00
jfs_metapage.c SL*B: drop kmem cache argument from constructor 2008-07-26 12:00:07 -07:00
jfs_metapage.h JFS: White space cleanup 2006-10-02 09:55:27 -05:00
jfs_mount.c JFS: Remove defconfig ptr comparison to 0 2008-01-03 13:12:10 -06:00
jfs_superblock.h JFS: White space cleanup 2006-10-02 09:55:27 -05:00
jfs_txnmgr.c JFS: switch to seq_files 2008-05-13 08:22:10 -05:00
jfs_txnmgr.h JFS: Whitespace cleanup and remove some dead code 2007-06-06 15:28:35 -05:00
jfs_types.h JFS: Whitespace cleanup and remove some dead code 2007-06-06 15:28:35 -05:00
jfs_umount.c JFS: Make sure special inode data is written after journal is flushed 2008-01-03 13:11:37 -06:00
jfs_unicode.c JFS: White space cleanup 2006-10-02 09:55:27 -05:00
jfs_unicode.h JFS: White space cleanup 2006-10-02 09:55:27 -05:00
jfs_uniupr.c JFS: White space cleanup 2006-10-02 09:55:27 -05:00
jfs_xattr.h JFS: White space cleanup 2006-10-02 09:55:27 -05:00
jfs_xtree.c JFS: switch to seq_files 2008-05-13 08:22:10 -05:00
jfs_xtree.h JFS: Whitespace cleanup and remove some dead code 2007-06-06 15:28:35 -05:00
Makefile JFS: ext2 inode attributes for jfs 2006-02-09 09:09:16 -06:00
namei.c nfsd race fixes: jfs 2008-12-31 18:07:44 -05:00
resize.c JFS: use DIV_ROUND_UP where appropriate 2008-01-03 13:11:59 -06:00
super.c filesystem freeze: add error handling of write_super_lockfs/unlockfs 2009-01-09 16:54:42 -08:00
symlink.c [PATCH] mark struct inode_operations const 2 2007-02-12 09:48:46 -08:00
xattr.c Introduce is_owner_or_cap() to wrap CAP_FOWNER use with fsuid check 2007-07-17 12:00:03 -07:00