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2009-06-11Push BKL down into ->remount_fs()Alessio Igor Bogani
[xfs, btrfs, capifs, shmem don't need BKL, exempt] Signed-off-by: Alessio Igor Bogani <abogani@texware.it> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11push BKL down into ->put_superChristoph Hellwig
Move BKL into ->put_super from the only caller. A couple of filesystems had trivial enough ->put_super (only kfree and NULLing of s_fs_info + stuff in there) to not get any locking: coda, cramfs, efs, hugetlbfs, omfs, qnx4, shmem, all others got the full treatment. Most of them probably don't need it, but I'd rather sort that out individually. Preferably after all the other BKL pushdowns in that area. [AV: original used to move lock_super() down as well; these changes are removed since we don't do lock_super() at all in generic_shutdown_super() now] [AV: fuse, btrfs and xfs are known to need no damn BKL, exempt] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11ocfs2: remove ->write_super and stop maintaining ->s_dirtChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-22block: Do away with the notion of hardsect_sizeMartin K. Petersen
Until now we have had a 1:1 mapping between storage device physical block size and the logical block sized used when addressing the device. With SATA 4KB drives coming out that will no longer be the case. The sector size will be 4KB but the logical block size will remain 512-bytes. Hence we need to distinguish between the physical block size and the logical ditto. This patch renames hardsect_size to logical_block_size. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-09ocfs2: Use nd_set_link().Joel Becker
ocfs2 was hand-calling vfs_follow_link(), but there's no point to that. Let's use page_follow_link_light() and nd_set_link(). Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-02Merge branch 'upstream-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2 * 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2: ocfs2: Change repository in MAINTAINERS. ocfs2: Fix a missing credit when deleting from indexed directories. ocfs2/trivial: Remove unused variable in ocfs2_rename. ocfs2: Add missing iput() during error handling in ocfs2_dentry_attach_lock() ocfs2: Fix some printk() warnings. ocfs2: Fix 2 warning during ocfs2 make. ocfs2: Reserve 1 more cluster in expanding_inline_dir for indexed dir.
2009-04-30ocfs2: Fix a missing credit when deleting from indexed directories.Joel Becker
The ocfs2 directory index updates two blocks when we remove an entry - the dx root and the dx leaf. OCFS2_DELETE_INODE_CREDITS was only accounting for the dx leaf. This shows up when ocfs2_delete_inode() runs out of credits in jbd2_journal_dirty_metadata() at "J_ASSERT_JH(jh, handle->h_buffer_credits > 0);". The test that caught this was running dirop_file_racer from the ocfs2-test suite with a 250-character filename PREFIX. Run on a 512B blocksize, it forces the orphan dir index to grow large enough to trigger. Signed-off-by: Joel Becker <joel.becker@oracle.com>
2009-04-29ocfs2/trivial: Remove unused variable in ocfs2_rename.Tao Ma
With indexed dir enabled, now we use ocfs2_dir_lookup_result to wrap all the bh used for dir. So remove the 2 unused variables. Signed-off-by: Tao Ma <tao.ma@oracle.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
2009-04-23ocfs2: Add missing iput() during error handling in ocfs2_dentry_attach_lock()Sunil Mushran
In ocfs2_dentry_attach_lock(), if unable to get the dentry lock, we need to call iput(inode) because a failure here means no d_instantiate(), which means the normally matching iput() will not be called during dput(dentry). This patch fixes the oops that accompanies the following message: (3996,1):dlm_empty_lockres:2708 ERROR: lockres W00000000000000000a1046b06a4382 still has local locks! kernel BUG in dlm_empty_lockres at /rpmbuild/smushran/BUILD/ocfs2-1.4.2/fs/ocfs2/dlm/dlmmaster.c:2709! Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
2009-04-21ocfs2: Fix some printk() warnings.Joel Becker
The old %llu vs u64 battle. Cast them correctly. Signed-off-by: Joel Becker <joel.becker@oracle.com>
2009-04-21ocfs2: Fix 2 warning during ocfs2 make.Tao Ma
fs/ocfs2/dir.c: In function ‘ocfs2_extend_dir’: fs/ocfs2/dir.c:2700: warning: ‘ret’ may be used uninitialized in this function fs/ocfs2/suballoc.c: In function ‘ocfs2_get_suballoc_slot_bit’: fs/ocfs2/suballoc.c:2216: warning: comparison is always true due to limited range of data type Signed-off-by: Tao Ma <tao.ma@oracle.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
2009-04-15ocfs2: fix i_mutex locking in ocfs2_splice_to_file()Miklos Szeredi
Rearrange locking of i_mutex on destination and call to ocfs2_rw_lock() so locks are only held while buffers are copied with the pipe_to_file() actor, and not while waiting for more data on the pipe. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-07ocfs2: Reserve 1 more cluster in expanding_inline_dir for indexed dir.Tao Ma
In ocfs2_expand_inline_dir, we calculate whether we need 1 extra cluster if we can't store the dx inline the root and save it in dx_alloc. So add it when we call ocfs2_reserve_clusters. Signed-off-by: Tao Ma <tao.ma@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-07splice: fix deadlock in splicing to fileMiklos Szeredi
There's a possible deadlock in generic_file_splice_write(), splice_from_pipe() and ocfs2_file_splice_write(): - task A calls generic_file_splice_write() - this calls inode_double_lock(), which locks i_mutex on both pipe->inode and target inode - ordering depends on inode pointers, can happen that pipe->inode is locked first - __splice_from_pipe() needs more data, calls pipe_wait() - this releases lock on pipe->inode, goes to interruptible sleep - task B calls generic_file_splice_write(), similarly to the first - this locks pipe->inode, then tries to lock inode, but that is already held by task A - task A is interrupted, it tries to lock pipe->inode, but fails, as it is already held by task B - ABBA deadlock Fix this by explicitly ordering locks: the outer lock must be on target inode and the inner lock (which is later unlocked and relocked) must be on pipe->inode. This is OK, pipe inodes and target inodes form two nonoverlapping sets, generic_file_splice_write() and friends are not called with a target which is a pipe. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Acked-by: Mark Fasheh <mfasheh@suse.com> Acked-by: Jens Axboe <jens.axboe@oracle.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-03ocfs2: recover orphans in offline slots during recovery and mountSrinivas Eeda
During recovery, a node recovers orphans in it's slot and the dead node(s). But if the dead nodes were holding orphans in offline slots, they will be left unrecovered. If the dead node is the last one to die and is holding orphans in other slots and is the first one to mount, then it only recovers it's own slot, which leaves orphans in offline slots. This patch queues complete_recovery to clean orphans for all offline slots during mount and node recovery. Signed-off-by: Srinivas Eeda <srinivas.eeda@oracle.com> Acked-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2: Pagecache usage optimization on ocfs2Hisashi Hifumi
A page can have multiple buffers and even if a page is not uptodate, some buffers can be uptodate on pagesize != blocksize environment. This aops checks that all buffers which correspond to a part of a file that we want to read are uptodate. If so, we do not have to issue actual read IO to HDD even if a page is not uptodate because the portion we want to read are uptodate. "block_is_partially_uptodate" function is already used by ext2/3/4. With the following patch random read/write mixed workloads or random read after random write workloads can be optimized and we can get performance improvement. Signed-off-by: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2: fix rare stale inode errors when exporting via nfswengang wang
For nfs exporting, ocfs2_get_dentry() returns the dentry for fh. ocfs2_get_dentry() may read from disk when the inode is not in memory, without any cross cluster lock. this leads to the file system loading a stale inode. This patch fixes above problem. Solution is that in case of inode is not in memory, we get the cluster lock(PR) of alloc inode where the inode in question is allocated from (this causes node on which deletion is done sync the alloc inode) before reading out the inode itsself. then we check the bitmap in the group (the inode in question allcated from) to see if the bit is clear. if it's clear then it's stale. if the bit is set, we then check generation as the existing code does. We have to read out the inode in question from disk first to know its alloc slot and allot bit. And if its not stale we read it out using ocfs2_iget(). The second read should then be from cache. And also we have to add a per superblock nfs_sync_lock to cover the lock for alloc inode and that for inode in question. this is because ocfs2_get_dentry() and ocfs2_delete_inode() lock on them in reverse order. nfs_sync_lock is locked in EX mode in ocfs2_get_dentry() and in PR mode in ocfs2_delete_inode(). so that mutliple ocfs2_delete_inode() can run concurrently in normal case. [mfasheh@suse.com: build warning fixes and comment cleanups] Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com> Acked-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2/dlm: Tweak mle_state outputSunil Mushran
The debugfs file, mle_state, now prints the number of largest number of mles in one hash link. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2/dlm: Do not purge lockres that is being migrated dlm_purge_lockres()Sunil Mushran
This patch attempts to fix a fine race between purging and migration. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2/dlm: Remove struct dlm_lock_name in struct dlm_master_list_entrySunil Mushran
This patch removes struct dlm_lock_name and adds the entries directly to struct dlm_master_list_entry. Under the new scheme, both mles that are backed by a lockres or not, will have the name populated in mle->mname. This allows us to get rid of code that was figuring out the location of the mle name. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2/dlm: Show the number of lockres/mles in dlm_stateSunil Mushran
This patch shows the number of lockres' and mles in the debugfs file, dlm_state. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2/dlm: dlm_set_lockres_owner() and dlm_change_lockres_owner() inlinedSunil Mushran
This patch inlines dlm_set_lockres_owner() and dlm_change_lockres_owner(). Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2/dlm: Improve lockres countsSunil Mushran
This patch replaces the lockres counts that tracked the number number of locally and remotely mastered lockres' with a current and total count. The total count is the number of lockres' that have been created since the dlm domain was created. The number of locally and remotely mastered counts can be computed using the locking_state output. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2/dlm: Track number of mlesSunil Mushran
The lifetime of a mle is limited to the duration of the lockres mastery process. While typically this lifetime is fairly short, we have noticed the number of mles explode under certain circumstances. This patch tracks the number of each different types of mles and should help us determine how best to speed up the mastery process. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2/dlm: Indent dlm_cleanup_master_list()Sunil Mushran
The previous patch explicitly did not indent dlm_cleanup_master_list() so as to make the patch readable. This patch properly indents the function. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2/dlm: Activate dlm->master_hash for master list entriesSunil Mushran
With this patch, the mles are stored in a hash and not a simple list. This should improve the mle lookup time when the number of outstanding masteries is large. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2/dlm: Create and destroy the dlm->master_hashSunil Mushran
This patch adds code to create and destroy the dlm->master_hash. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2/dlm: Refactor dlm_clean_master_list()Sunil Mushran
This patch refactors dlm_clean_master_list() so as to make it easier to convert the mle list to a hash. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2/dlm: Clean up struct dlm_lock_nameSunil Mushran
For master mle, the name it stored in the attached lockres in struct qstr. For block and migration mle, the name is stored inline in struct dlm_lock_name. This patch attempts to make struct dlm_lock_name look like a struct qstr. While we could use struct qstr, we don't because we want to avoid having to malloc and free the lockname string as the mle's lifetime is fairly short. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2/dlm: Encapsulate adding and removing of mle from dlm->master_listSunil Mushran
This patch encapsulates adding and removing of the mle from the dlm->master_list. This patch is part of the series of patches that converts the mle list to a mle hash. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2: Optimize inode group allocation by recording last used group.Tao Ma
In ocfs2, the block group search looks for the "emptiest" group to allocate from. So if the allocator has many equally(or almost equally) empty groups, new block group will tend to get spread out amongst them. So we add osb_inode_alloc_group in ocfs2_super to record the last used inode allocation group. For more details, please see http://oss.oracle.com/osswiki/OCFS2/DesignDocs/InodeAllocationStrategy. I have done some basic test and the results are a ten times improvement on some cold-cache stat workloads. Signed-off-by: Tao Ma <tao.ma@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2: Allocate inode groups from global_bitmap.Tao Ma
Inode groups used to be allocated from local alloc file, but since we want all inodes to be contiguous enough, we will try to allocate them directly from global_bitmap. Signed-off-by: Tao Ma <tao.ma@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2: Optimize inode allocation by remembering last groupTao Ma
In ocfs2, the inode block search looks for the "emptiest" inode group to allocate from. So if an inode alloc file has many equally (or almost equally) empty groups, new inodes will tend to get spread out amongst them, which in turn can put them all over the disk. This is undesirable because directory operations on conceptually "nearby" inodes force a large number of seeks. So we add ip_last_used_group in core directory inodes which records the last used allocation group. Another field named ip_last_used_slot is also added in case inode stealing happens. When claiming new inode, we passed in directory's inode so that the allocation can use this information. For more details, please see http://oss.oracle.com/osswiki/OCFS2/DesignDocs/InodeAllocationStrategy. Signed-off-by: Tao Ma <tao.ma@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2: fix leaf start calculation in ocfs2_dx_dir_rebalance()Mark Fasheh
ocfs2_dx_dir_rebalance() is passed the block offset of a dx leaf which needs rebalancing. Since we rebalance an entire cluster at a time however, this function needs to calculate the beginning of that cluster, in blocks. The calculation was wrong, which would result in a read of non-leaf blocks. Fix the calculation by adding ocfs2_block_to_cluster_start() which is a more straight-forward way of determining this. Reported-by: Tristan Ye <tristan.ye@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2: re-order ocfs2_empty_dir checksMark Fasheh
ocfs2_empty_dir() is far more expensive than checking link count. Since both need to be checked at the same time, we can improve performance by checking link count first. Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2: Enable indexed directoriesMark Fasheh
Since the disk format is finalized, we can set this feature bit in the supported mask. Signed-off-by: Mark Fasheh <mfasheh@suse.com> Acked-by: Joel Becker <Joel.Becker@oracle.com>
2009-04-03ocfs2: Add total entry count to dx_root_blockMark Fasheh
This little bit of extra accounting speeds up ocfs2_empty_dir() dramatically by allowing us to short-circuit the full directory scan. Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2: Increase max links countMark Fasheh
Since we've now got a directory format capable of handling a large number of entries, we can increase the maximum link count supported. This only gets increased if the directory indexing feature is turned on. Signed-off-by: Mark Fasheh <mfasheh@suse.com> Acked-by: Joel Becker <joel.becker@oracle.com>
2009-04-03ocfs2: Introduce dir free space listMark Fasheh
The only operation which doesn't get faster with directory indexing is insert, which still has to walk the entire unindexed directory portion to find a free block. This patch provides an improvement in directory insert performance by maintaining a singly linked list of directory leaf blocks which have space for additional dirents. Signed-off-by: Mark Fasheh <mfasheh@suse.com> Acked-by: Joel Becker <joel.becker@oracle.com>
2009-04-03ocfs2: Store dir index records inlineMark Fasheh
Allow us to store a small number of directory index records in the ocfs2_dx_root_block. This saves us a disk read on small to medium sized directories (less than about 250 entries). The inline root is automatically turned into a root block with extents if the directory size increases beyond it's capacity. Signed-off-by: Mark Fasheh <mfasheh@suse.com> Acked-by: Joel Becker <joel.becker@oracle.com>
2009-04-03ocfs2: Add a name indexed b-tree to directory inodesMark Fasheh
This patch makes use of Ocfs2's flexible btree code to add an additional tree to directory inodes. The new tree stores an array of small, fixed-length records in each leaf block. Each record stores a hash value, and pointer to a block in the traditional (unindexed) directory tree where a dirent with the given name hash resides. Lookup exclusively uses this tree to find dirents, thus providing us with constant time name lookups. Some of the hashing code was copied from ext3. Unfortunately, it has lots of unfixed checkpatch errors. I left that as-is so that tracking changes would be easier. Signed-off-by: Mark Fasheh <mfasheh@suse.com> Acked-by: Joel Becker <joel.becker@oracle.com>
2009-04-03ocfs2: Introduce dir lookup helper structMark Fasheh
Many directory manipulation calls pass around a tuple of dirent, and it's containing buffer_head. Dir indexing has a bit more state, but instead of adding yet more arguments to functions, we introduce 'struct ocfs2_dir_lookup_result'. In this patch, it simply holds the same tuple, but future patches will add more state. Signed-off-by: Mark Fasheh <mfasheh@suse.com> Acked-by: Joel Becker <joel.becker@oracle.com>
2009-04-03ocfs2: Remove debugfs file local_alloc_statsSunil Mushran
This patch removes the debugfs file local_alloc_stats as that information is now included in the fs_state debugfs file. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2: Expose the file system state via debugfsSunil Mushran
This patch creates a per mount debugfs file, fs_state, which exposes information like, cluster stack in use, states of the downconvert, recovery and commit threads, number of journal txns, some allocation stats, list of all slots, etc. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2: Move struct recovery_map to a header fileSunil Mushran
Move the definition of struct recovery_map from journal.c to journal.h. This is preparation for the next patch. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03ocfs2/hb: Expose the list of heartbeating nodes via debugfsSunil Mushran
This patch creates a debugfs file, o2hb/livesnodes, which exposes the aggregate list of heartbeating node across all heartbeat regions. Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-02Merge 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: Remove two unneeded exports and make two symbols static in fs/mpage.c Cleanup after commit 585d3bc06f4ca57f975a5a1f698f65a45ea66225 Trim includes of fdtable.h Don't crap into descriptor table in binfmt_som Trim includes in binfmt_elf Don't mess with descriptor table in load_elf_binary() Get rid of indirect include of fs_struct.h New helper - current_umask() check_unsafe_exec() doesn't care about signal handlers sharing New locking/refcounting for fs_struct Take fs_struct handling to new file (fs/fs_struct.c) Get rid of bumping fs_struct refcount in pivot_root(2) Kill unsharing fs_struct in __set_personality()
2009-04-01mm: page_mkwrite change prototype to match faultNick Piggin
Change the page_mkwrite prototype to take a struct vm_fault, and return VM_FAULT_xxx flags. There should be no functional change. This makes it possible to return much more detailed error information to the VM (and also can provide more information eg. virtual_address to the driver, which might be important in some special cases). This is required for a subsequent fix. And will also make it easier to merge page_mkwrite() with fault() in future. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Chris Mason <chris.mason@oracle.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <joel.becker@oracle.com> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Felix Blyakher <felixb@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-31New helper - current_umask()Al Viro
current->fs->umask is what most of fs_struct users are doing. Put that into a helper function. 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>