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2009-03-04ext4: Use struct flex_groups to calculate get_orlov_stats()Theodore Ts'o
Instead of looping over all of the block groups in a flex group summing their summary statistics, start tracking used_dirs in struct flex_groups, and use struct flex_groups instead. This should save a bit of CPU for mkdir-heavy workloads. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-04ext4: Use atomic_t's in struct flex_groupsTheodore Ts'o
Reduce pressure on the sb_bgl_lock family of locks by using atomic_t's to track the number of free blocks and inodes in each flex_group. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-31ext4: remove /proc tuning knobsTheodore Ts'o
Remove tuning knobs in /proc/fs/ext4/<dev/* since they have been replaced by knobs in sysfs at /sys/fs/ext4/<dev>/*. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-31ext4: Add sysfs supportTheodore Ts'o
Add basic sysfs support so that information about the mounted filesystem and various tuning parameters can be accessed via /sys/fs/ext4/<dev>/*. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-28ext4: Track lifetime disk writesTheodore Ts'o
Add a new superblock value which tracks the lifetime amount of writes to the filesystem. This is useful in estimating the amount of wear on solid state drives (SSD's) caused by writes to the filesystem. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-27ext4: Fix discard of inode prealloc space with delayed allocation.Aneesh Kumar K.V
With delayed allocation we should not/cannot discard inode prealloc space during file close. We would still have dirty pages for which we haven't allocated blocks yet. With this fix after each get_blocks request we check whether we have zero reserved blocks and if yes and we don't have any writers on the file we discard inode prealloc space. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-23ext4: Automatically allocate delay allocated blocks on renameTheodore Ts'o
When renaming a file such that a link to another inode is overwritten, force any delay allocated blocks that to be allocated so that if the filesystem is mounted with data=ordered, the data blocks will be pushed out to disk along with the journal commit. Many application programs expect this, so we do this to avoid zero length files if the system crashes unexpectedly. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-24ext4: Automatically allocate delay allocated blocks on closeTheodore Ts'o
When closing a file that had been previously truncated, force any delay allocated blocks that to be allocated so that if the filesystem is mounted with data=ordered, the data blocks will be pushed out to disk along with the journal commit. Many application programs expect this, so we do this to avoid zero length files if the system crashes unexpectedly. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-26ext4: add EXT4_IOC_ALLOC_DA_BLKS ioctlTheodore Ts'o
Add an ioctl which forces all of the delay allocated blocks to be allocated. This also provides a function ext4_alloc_da_blocks() which will be used by the following commits to force files to be fully allocated to preserve application-expected ext3 behaviour. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-23ext4: Simplify delalloc code by removing mpage_da_writepages()Theodore Ts'o
The mpage_da_writepages() function is only used in one place, so inline it to simplify the call stack and make the code easier to understand. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-23ext4: Save stack space by removing fake buffer headsTheodore Ts'o
Struct mpage_da_data and mpage_add_bh_to_extent() use a fake struct buffer_head which is 104 bytes on an x86_64 system, but only use 24 bytes of the structure. On systems that use a spinlock for atomic_t, the stack savings will be even greater. It turns out that using a fake struct buffer_head doesn't even save that much code, and it makes the code more confusing since it's not used as a "real" buffer head. So just store pass b_size and b_state in mpage_add_bh_to_extent(), and store b_size, b_state, and b_block_nr in the mpage_da_data structure. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-23ext4: Simplify delalloc implementation by removing mpd.get_blockTheodore Ts'o
This parameter was always set to ext4_da_get_block_write(). Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-27ext4: Validate extent details only when read from the diskAneesh Kumar K.V
Make sure we validate extent details only when read from the disk. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Thiemo Nagel <thiemo.nagel@ph.tum.de> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-12ext4: Add checks to validate extent entries.Aneesh Kumar K.V
This patch adds checks to validate the extent entries along with extent headers, to avoid crashes caused by corrupt filesystems. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-22ext4: return -EIO not -ESTALE on directory traversal through deleted inodeBryan Donlan
ext4_iget() returns -ESTALE if invoked on a deleted inode, in order to report errors to NFS properly. However, in ext4_lookup(), this -ESTALE can be propagated to userspace if the filesystem is corrupted such that a directory entry references a deleted inode. This leads to a misleading error message - "Stale NFS file handle" - and confusion on the part of the admin. The bug can be easily reproduced by creating a new filesystem, making a link to an unused inode using debugfs, then mounting and attempting to ls -l said link. This patch thus changes ext4_lookup to return -EIO if it receives -ESTALE from ext4_iget(), as ext4 does for other filesystem metadata corruption; and also invokes the appropriate ext*_error functions when this case is detected. Signed-off-by: Bryan Donlan <bdonlan@gmail.com> Cc: <linux-ext4@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-12ext4: New inode/block allocation algorithms for flex_bg filesystemsTheodore Ts'o
The find_group_flex() inode allocator is now only used if the filesystem is mounted using the "oldalloc" mount option. It is replaced with the original Orlov allocator that has been updated for flex_bg filesystems (it should behave the same way if flex_bg is disabled). The inode allocator now functions by taking into account each flex_bg group, instead of each block group, when deciding whether or not it's time to allocate a new directory into a fresh flex_bg. The block allocator has also been changed so that the first block group in each flex_bg is preferred for use for storing directory blocks. This keeps directory blocks close together, which is good for speeding up e2fsck since large directories are more likely to look like this: debugfs: stat /home/tytso/Maildir/cur Inode: 1844562 Type: directory Mode: 0700 Flags: 0x81000 Generation: 1132745781 Version: 0x00000000:0000ad71 User: 15806 Group: 15806 Size: 1060864 File ACL: 0 Directory ACL: 0 Links: 2 Blockcount: 2072 Fragment: Address: 0 Number: 0 Size: 0 ctime: 0x499c0ff4:164961f4 -- Wed Feb 18 08:41:08 2009 atime: 0x499c0ff4:00000000 -- Wed Feb 18 08:41:08 2009 mtime: 0x49957f51:00000000 -- Fri Feb 13 09:10:25 2009 crtime: 0x499c0f57:00d51440 -- Wed Feb 18 08:38:31 2009 Size of extra inode fields: 28 BLOCKS: (0):7348651, (1-258):7348654-7348911 TOTAL: 259 Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-15ext4: tighten restrictions on inode flagsDuane Griffin
At the moment there are few restrictions on which flags may be set on which inodes. Specifically DIRSYNC may only be set on directories and IMMUTABLE and APPEND may not be set on links. Tighten that to disallow TOPDIR being set on non-directories and only NODUMP and NOATIME to be set on non-regular file, non-directories. Introduces a flags masking function which masks flags based on mode and use it during inode creation and when flags are set via the ioctl to facilitate future consistency. Signed-off-by: Duane Griffin <duaneg@dghda.com> Acked-by: Andreas Dilger <adilger@sun.com> Cc: <linux-ext4@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-15ext4: don't inherit inappropriate inode flags from parentDuane Griffin
At present INDEX and EXTENTS are the only flags that new ext4 inodes do NOT inherit from their parent. In addition prevent the flags DIRTY, ECOMPR, IMAGIC, TOPDIR, HUGE_FILE and EXT_MIGRATE from being inherited. List inheritable flags explicitly to prevent future flags from accidentally being inherited. This fixes the TOPDIR flag inheritance bug reported at http://bugzilla.kernel.org/show_bug.cgi?id=9866. Signed-off-by: Duane Griffin <duaneg@dghda.com> Acked-by: Andreas Dilger <adilger@sun.com> Cc: <linux-ext4@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-15ext4: allocate ->s_blockgroup_lock separatelyPekka Enberg
As spotted by kmemtrace, struct ext4_sb_info is 17664 bytes on 64-bit which makes it a very bad fit for SLAB allocators. The culprit of the wasted memory is ->s_blockgroup_lock which can be as big as 16 KB when NR_CPUS >= 32. To fix that, allocate ->s_blockgroup_lock, which fits nicely in a order 2 page in the worst case, separately. This shinks down struct ext4_sb_info enough to fit a 2 KB slab cache so now we allocate 16 KB + 2 KB instead of 32 KB saving 14 KB of memory. Acked-by: Andreas Dilger <adilger@sun.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Cc: <linux-ext4@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-14ext4: New rec_len encoding for very large blocksizesWei Yongjun
The rec_len field in the directory entry is 16 bits, so to encode blocksizes larger than 64k becomes problematic. This patch allows us to supprot block sizes up to 256k, by using the low 2 bits to extend the range of rec_len to 2**18-1 (since valid rec_len sizes must be a multiple of 4). We use the convention that a rec_len of 0 or 65535 means the filesystem block size, for compatibility with older kernels. It's unlikely we'll see VM pages of up to 256k, but at some point we might find that the Linux VM has been enhanced to support filesystem block sizes > than the VM page size, at which point it might be useful for some applications to allow very large filesystem block sizes. Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-14ext4: Use unsigned int for blocksize in dx_make_map() and dx_pack_dirents()Theodore Ts'o
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-06ext4: remove call to ext4_group_desc() in ext4_group_used_meta_blocks()Theodore Ts'o
The static function ext4_group_used_meta_blocks() only has one caller, who already has access to the block group's group descriptor. So it's better to have ext4_init_block_bitmap() pass the group descriptor to ext4_group_used_meta_blocks(), so it doesn't need to call ext4_group_desc(). Previously this function did not check if ext4_group_desc() returned NULL due to an error, potentially causing a kernel OOPS report. This avoids the issue entirely. Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-06ext4: Remove stale block allocator references from ext4.hMike Snitzer
Remove some leftovers from when the old block allocator was removed (c2ea3fde). ext4_sb_info is now a bit lighter. Also remove a dangling read_block_bitmap() prototype. Signed-off-by: Mike Snitzer <snitzer@gmail.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-28fix setuid sometimes wouldn'tHugh Dickins
check_unsafe_exec() also notes whether the fs_struct is being shared by more threads than will get killed by the exec, and if so sets LSM_UNSAFE_SHARE to make bprm_set_creds() careful about euid. But /proc/<pid>/cwd and /proc/<pid>/root lookups make transient use of get_fs_struct(), which also raises that sharing count. This might occasionally cause a setuid program not to change euid, in the same way as happened with files->count (check_unsafe_exec also looks at sighand->count, but /proc doesn't raise that one). We'd prefer exec not to unshare fs_struct: so fix this in procfs, replacing get_fs_struct() by get_fs_path(), which does path_get while still holding task_lock, instead of raising fs->count. Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: stable@kernel.org ___ fs/proc/base.c | 50 +++++++++++++++-------------------------------- 1 file changed, 16 insertions(+), 34 deletions(-) Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-28fix setuid sometimes doesn'tHugh Dickins
Joe Malicki reports that setuid sometimes doesn't: very rarely, a setuid root program does not get root euid; and, by the way, they have a health check running lsof every few minutes. Right, check_unsafe_exec() notes whether the files_struct is being shared by more threads than will get killed by the exec, and if so sets LSM_UNSAFE_SHARE to make bprm_set_creds() careful about euid. But /proc/<pid>/fd and /proc/<pid>/fdinfo lookups make transient use of get_files_struct(), which also raises that sharing count. There's a rather simple fix for this: exec's check on files->count has been redundant ever since 2.6.1 made it unshare_files() (except while compat_do_execve() omitted to do so) - just remove that check. [Note to -stable: this patch will not apply before 2.6.29: earlier releases should just remove the files->count line from unsafe_exec().] Reported-by: Joe Malicki <jmalicki@metacarta.com> Narrowed-down-by: Michael Itz <mitz@metacarta.com> Tested-by: Joe Malicki <jmalicki@metacarta.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-28compat_do_execve should unshare_filesHugh Dickins
2.6.26's commit fd8328be874f4190a811c58cd4778ec2c74d2c05 "sanitize handling of shared descriptor tables in failing execve()" moved the unshare_files() from flush_old_exec() and several binfmts to the head of do_execve(); but forgot to make the same change to compat_do_execve(), leaving a CLONE_FILES files_struct shared across exec from a 32-bit process on a 64-bit kernel. It's arguable whether the files_struct really ought to be unshared across exec; but 2.6.1 made that so to stop the loading binary's fd leaking into other threads, and a 32-bit process on a 64-bit kernel ought to behave in the same way as 32 on 32 and 64 on 64. Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-27Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (37 commits) fs: avoid I_NEW inodes Merge code for single and multiple-instance mounts Remove get_init_pts_sb() Move common mknod_ptmx() calls into caller Parse mount options just once and copy them to super block Unroll essentials of do_remount_sb() into devpts vfs: simple_set_mnt() should return void fs: move bdev code out of buffer.c constify dentry_operations: rest constify dentry_operations: configfs constify dentry_operations: sysfs constify dentry_operations: JFS constify dentry_operations: OCFS2 constify dentry_operations: GFS2 constify dentry_operations: FAT constify dentry_operations: FUSE constify dentry_operations: procfs constify dentry_operations: ecryptfs constify dentry_operations: CIFS constify dentry_operations: AFS ...
2009-03-27Merge branch 'for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-quota-2.6 * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-quota-2.6: (27 commits) ext2: Zero our b_size in ext2_quota_read() trivial: fix typos/grammar errors in fs/Kconfig quota: Coding style fixes quota: Remove superfluous inlines quota: Remove uppercase aliases for quota functions. nfsd: Use lowercase names of quota functions jfs: Use lowercase names of quota functions udf: Use lowercase names of quota functions ufs: Use lowercase names of quota functions reiserfs: Use lowercase names of quota functions ext4: Use lowercase names of quota functions ext3: Use lowercase names of quota functions ext2: Use lowercase names of quota functions ramfs: Remove quota call vfs: Use lowercase names of quota functions quota: Remove dqbuf_t and other cleanups quota: Remove NODQUOT macro quota: Make global quota locks cacheline aligned quota: Move quota files into separate directory ext4: quota reservation for delayed allocation ...
2009-03-27Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm: dlm: fix length calculation in compat code dlm: ignore cancel on granted lock dlm: clear defunct cancel state dlm: replace idr with hash table for connections dlm: comment typo fixes dlm: use ipv6_addr_copy dlm: Change rwlock which is only used in write mode to a spinlock
2009-03-27fs: avoid I_NEW inodesNick Piggin
To be on the safe side, it should be less fragile to exclude I_NEW inodes from inode list scans by default (unless there is an important reason to have them). Normally they will get excluded (eg. by zero refcount or writecount etc), however it is a bit fragile for list walkers to know exactly what parts of the inode state is set up and valid to test when in I_NEW. So along these lines, move I_NEW checks upward as well (sometimes taking I_FREEING etc checks with them too -- this shouldn't be a problem should it?) Signed-off-by: Nick Piggin <npiggin@suse.de> Acked-by: Jan Kara <jack@suse.cz> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27Merge code for single and multiple-instance mountsSukadev Bhattiprolu
new_pts_mount() (including the get_sb_nodev()), shares a lot of code with init_pts_mount(). The only difference between them is the 'test-super' function passed into sget(). Move all common code into devpts_get_sb() and remove the new_pts_mount() and init_pts_mount() functions, Changelog[v3]: [Serge Hallyn]: Remove unnecessary printk()s Changelog[v2]: (Christoph Hellwig): Merge code in 'do_pts_mount()' into devpts_get_sb() Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Tested-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27Remove get_init_pts_sb()Sukadev Bhattiprolu
With mknod_ptmx() moved to devpts_get_sb(), init_pts_mount() becomes a wrapper around get_init_pts_sb(). Remove get_init_pts_sb() and fold code into init_pts_mount(). Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27Move common mknod_ptmx() calls into callerSukadev Bhattiprolu
We create 'ptmx' node in both single-instance and multiple-instance mounts. So devpts_get_sb() can call mknod_ptmx() once rather than have both modes calling mknod_ptmx() separately. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27Parse mount options just once and copy them to super blockSukadev Bhattiprolu
Since all the mount option parsing is done in devpts, we could do it just once and pass it around in devpts functions and eventually store it in the super block. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27Unroll essentials of do_remount_sb() into devptsSukadev Bhattiprolu
On remount, devpts fs only needs to parse the mount options. Users cannot directly create/dirty files in /dev/pts so the MS_RDONLY flag and shrinking the dcache does not really apply to devpts. So effectively on remount, devpts only parses the mount options and updates these options in its super block. As such, we could replace do_remount_sb() call with a direct parse_mount_options(). Doing so enables subsequent patches to avoid parsing the mount options twice and simplify the code. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27vfs: simple_set_mnt() should return voidSukadev Bhattiprolu
simple_set_mnt() is defined as returning 'int' but always returns 0. Callers assume simple_set_mnt() never fails and don't properly cleanup if it were to _ever_ fail. For instance, get_sb_single() and get_sb_nodev() should: up_write(sb->s_unmount); deactivate_super(sb); if simple_set_mnt() fails. Since simple_set_mnt() never fails, would be cleaner if it did not return anything. [akpm@linux-foundation.org: fix build] Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27fs: move bdev code out of buffer.cNick Piggin
Move some block device related code out from buffer.c and put it in block_dev.c. I'm trying to move non-buffer_head code out of buffer.c Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27constify dentry_operations: restAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27constify dentry_operations: configfsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27constify dentry_operations: sysfsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27constify dentry_operations: JFSAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27constify dentry_operations: OCFS2Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27constify dentry_operations: GFS2Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27constify dentry_operations: FATAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27constify dentry_operations: FUSEAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27constify dentry_operations: procfsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27constify dentry_operations: ecryptfsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27constify dentry_operations: CIFSAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27constify dentry_operations: AFSAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27constify dentry_operations: autofs, autofs4Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>