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2013-10-28NFS: Export _nfs_display_fhandle()Chuck Lever
Allow code in nfsv4.ko to use _nfs_display_fhandle(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28NFS: Introduce a vector of migration recovery opsChuck Lever
The differences between minor version 0 and minor version 1 migration will be abstracted by the addition of a set of migration recovery ops. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28NFS: Add functions to swap transports during migration recoveryChuck Lever
Introduce functions that can walk through an array of returned fs_locations information and connect a transport to one of the destination servers listed therein. Note that NFS minor version 1 introduces "fs_locations_info" which extends the locations array sorting criteria available to clients. This is not supported yet. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28NFS: Add nfs4_update_serverChuck Lever
New function nfs4_update_server() moves an nfs_server to a different nfs_client. This is done as part of migration recovery. Though it may be appealing to think of them as the same thing, migration recovery is not the same as following a referral. For a referral, the client has not descended into the file system yet: it has no nfs_server, no super block, no inodes or open state. It is enough to simply instantiate the nfs_server and super block, and perform a referral mount. For a migration, however, we have all of those things already, and they have to be moved to a different nfs_client. No local namespace changes are needed here. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28NFSv4: don't reprocess cached open CLAIM_PREVIOUSWeston Andros Adamson
Cached opens have already been handled by _nfs4_opendata_reclaim_to_nfs4_state and can safely skip being reprocessed, but must still call update_open_stateid to make sure that all active fmodes are recovered. Signed-off-by: Weston Andros Adamson <dros@netapp.com> Cc: stable@vger.kernel.org # 3.7.x: f494a6071d3: NFSv4: fix NULL dereference Cc: stable@vger.kernel.org # 3.7.x: a43ec98b72a: NFSv4: don't fail on missin Cc: stable@vger.kernel.org # 3.7.x Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28NFSv4: Fix state reference counting in _nfs4_opendata_reclaim_to_nfs4_stateTrond Myklebust
Currently, if the call to nfs_refresh_inode fails, then we end up leaking a reference count, due to the call to nfs4_get_open_state. While we're at it, replace nfs4_get_open_state with a simple call to atomic_inc(); there is no need to do a full lookup of the struct nfs_state since it is passed as an argument in the struct nfs4_opendata, and is already assigned to the variable 'state'. Cc: stable@vger.kernel.org # 3.7.x: a43ec98b72a: NFSv4: don't fail on missing Cc: stable@vger.kernel.org # 3.7.x Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28NFSv4: don't fail on missing fattr in open recoverWeston Andros Adamson
This is an unneeded check that could cause the client to fail to recover opens. Signed-off-by: Weston Andros Adamson <dros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28NFSv4: fix NULL dereference in open recoverWeston Andros Adamson
_nfs4_opendata_reclaim_to_nfs4_state doesn't expect to see a cached open CLAIM_PREVIOUS, but this can happen. An example is when there are RDWR openers and RDONLY openers on a delegation stateid. The recovery path will first try an open CLAIM_PREVIOUS for the RDWR openers, this marks the delegation as not needing RECLAIM anymore, so the open CLAIM_PREVIOUS for the RDONLY openers will not actually send an rpc. The NULL dereference is due to _nfs4_opendata_reclaim_to_nfs4_state returning PTR_ERR(rpc_status) when !rpc_done. When the open is cached, rpc_done == 0 and rpc_status == 0, thus _nfs4_opendata_reclaim_to_nfs4_state returns NULL - this is unexpected by callers of nfs4_opendata_to_nfs4_state(). This can be reproduced easily by opening the same file two times on an NFSv4.0 mount with delegations enabled, once as RDWR and once as RDONLY then sleeping for a long time. While the files are held open, kick off state recovery and this NULL dereference will be hit every time. An example OOPS: [ 65.003602] BUG: unable to handle kernel NULL pointer dereference at 00000000 00000030 [ 65.005312] IP: [<ffffffffa037d6ee>] __nfs4_close+0x1e/0x160 [nfsv4] [ 65.006820] PGD 7b0ea067 PUD 791ff067 PMD 0 [ 65.008075] Oops: 0000 [#1] SMP [ 65.008802] Modules linked in: rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache snd_ens1371 gameport nfsd snd_rawmidi snd_ac97_codec ac97_bus btusb snd_seq snd _seq_device snd_pcm ppdev bluetooth auth_rpcgss coretemp snd_page_alloc crc32_pc lmul crc32c_intel ghash_clmulni_intel microcode rfkill nfs_acl vmw_balloon serio _raw snd_timer lockd parport_pc e1000 snd soundcore parport i2c_piix4 shpchp vmw _vmci sunrpc ata_generic mperf pata_acpi mptspi vmwgfx ttm scsi_transport_spi dr m mptscsih mptbase i2c_core [ 65.018684] CPU: 0 PID: 473 Comm: 192.168.10.85-m Not tainted 3.11.2-201.fc19 .x86_64 #1 [ 65.020113] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/31/2013 [ 65.022012] task: ffff88003707e320 ti: ffff88007b906000 task.ti: ffff88007b906000 [ 65.023414] RIP: 0010:[<ffffffffa037d6ee>] [<ffffffffa037d6ee>] __nfs4_close+0x1e/0x160 [nfsv4] [ 65.025079] RSP: 0018:ffff88007b907d10 EFLAGS: 00010246 [ 65.026042] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 65.027321] RDX: 0000000000000050 RSI: 0000000000000001 RDI: 0000000000000000 [ 65.028691] RBP: ffff88007b907d38 R08: 0000000000016f60 R09: 0000000000000000 [ 65.029990] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 [ 65.031295] R13: 0000000000000050 R14: 0000000000000000 R15: 0000000000000001 [ 65.032527] FS: 0000000000000000(0000) GS:ffff88007f600000(0000) knlGS:0000000000000000 [ 65.033981] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 65.035177] CR2: 0000000000000030 CR3: 000000007b27f000 CR4: 00000000000407f0 [ 65.036568] Stack: [ 65.037011] 0000000000000000 0000000000000001 ffff88007b907d90 ffff88007a880220 [ 65.038472] ffff88007b768de8 ffff88007b907d48 ffffffffa037e4a5 ffff88007b907d80 [ 65.039935] ffffffffa036a6c8 ffff880037020e40 ffff88007a880000 ffff880037020e40 [ 65.041468] Call Trace: [ 65.042050] [<ffffffffa037e4a5>] nfs4_close_state+0x15/0x20 [nfsv4] [ 65.043209] [<ffffffffa036a6c8>] nfs4_open_recover_helper+0x148/0x1f0 [nfsv4] [ 65.044529] [<ffffffffa036a886>] nfs4_open_recover+0x116/0x150 [nfsv4] [ 65.045730] [<ffffffffa036d98d>] nfs4_open_reclaim+0xad/0x150 [nfsv4] [ 65.046905] [<ffffffffa037d979>] nfs4_do_reclaim+0x149/0x5f0 [nfsv4] [ 65.048071] [<ffffffffa037e1dc>] nfs4_run_state_manager+0x3bc/0x670 [nfsv4] [ 65.049436] [<ffffffffa037de20>] ? nfs4_do_reclaim+0x5f0/0x5f0 [nfsv4] [ 65.050686] [<ffffffffa037de20>] ? nfs4_do_reclaim+0x5f0/0x5f0 [nfsv4] [ 65.051943] [<ffffffff81088640>] kthread+0xc0/0xd0 [ 65.052831] [<ffffffff81088580>] ? insert_kthread_work+0x40/0x40 [ 65.054697] [<ffffffff8165686c>] ret_from_fork+0x7c/0xb0 [ 65.056396] [<ffffffff81088580>] ? insert_kthread_work+0x40/0x40 [ 65.058208] Code: 5c 41 5d 5d c3 0f 1f 84 00 00 00 00 00 66 66 66 66 90 55 48 89 e5 41 57 41 89 f7 41 56 41 89 ce 41 55 41 89 d5 41 54 53 48 89 fb <4c> 8b 67 30 f0 41 ff 44 24 44 49 8d 7c 24 40 e8 0e 0a 2d e1 44 [ 65.065225] RIP [<ffffffffa037d6ee>] __nfs4_close+0x1e/0x160 [nfsv4] [ 65.067175] RSP <ffff88007b907d10> [ 65.068570] CR2: 0000000000000030 [ 65.070098] ---[ end trace 0d1fe4f5c7dd6f8b ]--- Cc: <stable@vger.kernel.org> #3.7+ Signed-off-by: Weston Andros Adamson <dros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28NFSv4.1: Don't change the security label as part of open reclaim.Trond Myklebust
The current caching model calls for the security label to be set on first lookup and/or on any subsequent label changes. There is no need to do it as part of an open reclaim. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28nfs: fix handling of invalid mount options in nfs_remountJeff Layton
nfs_parse_mount_options returns 0 on error, not -errno. Reported-by: Karel Zak <kzak@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28nfs: reject version and minorversion changes on remount attemptsJeff Layton
Reported-by: Eric Doutreleau <edoutreleau@genoscope.cns.fr> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28NFSv4 Remove zeroing state kern warningsAndy Adamson
As of commit 5d422301f97b821301efcdb6fc9d1a83a5c102d6 we no longer zero the state. Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2013-10-28cifs: Remove redundant multiplex identifier check from check_smb_hdr()Tim Gardner
The only call site for check_smb_header() assigns 'mid' from the SMB packet, which is then checked again in check_smb_header(). This seems like redundant redundancy. Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Tim Gardner <timg@tpi.com> Signed-off-by: Steve French <smfrench@gmail.com>
2013-10-28Query file system attributes from server on SMB2, not just cifs, mountsSteve French
Currently SMB2 and SMB3 mounts do not query the file system attributes from the server at mount time as is done for cifs. These can be useful for debugging. Signed-off-by: Steve French <smfrench@gmail.com>
2013-10-28Allow setting per-file compression via SMB2/3Steve French
Allow cifs/smb2/smb3 to return whether or not a file is compressed via lsattr, and allow SMB2/SMB3 to set the per-file compression flag ("chattr +c filename" on an smb3 mount). Windows users often set the compressed flag (it can be done from the desktop and file manager). David Disseldorp has patches to Samba server to support this (at least on btrfs) which are complementary to this Signed-off-by: Steve French <smfrench@gmail.com>
2013-10-28Fix corrupt SMB2 ioctl requestsSteve French
We were off by one calculating the length of ioctls in some cases because the protocol specification for SMB2 ioctl includes a mininum one byte payload but not all SMB2 ioctl requests actually have a data buffer to send. We were also not zeroing out the return buffer (in case of error this is helpful). Signed-off-by: Steve French <smfrench@gmail.com>
2013-10-28f2fs: fix a deadlock during init_acl procedureJaegeuk Kim
The deadlock is found through the following scenario. sys_mkdir() -> f2fs_add_link() -> __f2fs_add_link() -> init_inode_metadata() : lock_page(inode); -> f2fs_init_acl() -> f2fs_set_acl() -> f2fs_setxattr(..., NULL) : This NULL page incurs a deadlock at update_inode_page(). So, likewise f2fs_init_security(), this patch adds a parameter to transfer the locked inode page to f2fs_setxattr(). Found by Linux File System Verification project (linuxtesting.org). Reported-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-28f2fs: clean up acl flow for better readabilityJaegeuk Kim
This patch cleans up a couple of acl codes. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-28f2fs: remove unnecessary segment bitmap updatesChangman Lee
Only one dirty type is set in __locate_dirty_segment and we can know dirty type of segment. So we don't need to check other dirty types. Signed-off-by: Changman Lee <cm224.lee@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-27jffs2: do not support the MLC nandHuang Shijie
We should not support the MLC nand for jffs2. So if the nand type is MLC, we quit immediatly. Signed-off-by: Huang Shijie <b32955@freescale.com> Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-10-26nfsd: fix Kconfig syntaxChristoph Hellwig
The description text for CONFIG_NFSD_V4_SECURITY_LABEL has an unpaired quote sign which breaks syntax highlighting for the nfsd Kconfig file. Remove it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-10-26UBIFS: correct data corruption rangeMats Kärrman
With power-cut emulation, it is possible that sometimes no data at all is corrupted and that confusing messages are printed due to errors in the computation of data corruption range. [1] The start of the range should be [0..len-1], not [0..len]. [2] The end of the range should always be at least 1 greater than the start. Signed-off-by: Mats Karrman <mats.karrman@tritech.se> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2013-10-26UBIFS: fix return codeWei Yongjun
Fix to return -ENOMEM in the kmalloc() and d_make_root() error handling case instead of 0, as done elsewhere in those functions. Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2013-10-25Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs fixes (try two) from Al Viro: "nfsd performance regression fix + seq_file lseek(2) fix" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: seq_file: always update file->f_pos in seq_lseek() nfsd regression since delayed fput()
2013-10-25seq_file: always update file->f_pos in seq_lseek()Gu Zheng
This issue was first pointed out by Jiaxing Wang several months ago, but no further comments: https://lkml.org/lkml/2013/6/29/41 As we know pread() does not change f_pos, so after pread(), file->f_pos and m->read_pos become different. And seq_lseek() does not update file->f_pos if offset equals to m->read_pos, so after pread() and seq_lseek()(lseek to m->read_pos), then a subsequent read may read from a wrong position, the following program produces the problem: char str1[32] = { 0 }; char str2[32] = { 0 }; int poffset = 10; int count = 20; /*open any seq file*/ int fd = open("/proc/modules", O_RDONLY); pread(fd, str1, count, poffset); printf("pread:%s\n", str1); /*seek to where m->read_pos is*/ lseek(fd, poffset+count, SEEK_SET); /*supposed to read from poffset+count, but this read from position 0*/ read(fd, str2, count); printf("read:%s\n", str2); out put: pread: ck_netbios_ns 12665 read: nf_conntrack_netbios /proc/modules: nf_conntrack_netbios_ns 12665 0 - Live 0xffffffffa038b000 nf_conntrack_broadcast 12589 1 nf_conntrack_netbios_ns, Live 0xffffffffa0386000 So we always update file->f_pos to offset in seq_lseek() to fix this issue. Signed-off-by: Jiaxing Wang <hello.wjx@gmail.com> Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-25f2fs: add tracepoint for vm_page_mkwriteJaegeuk Kim
This patch adds a tracepoint for f2fs_vm_page_mkwrite. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25f2fs: add tracepoint for set_page_dirtyJaegeuk Kim
This patch adds a tracepoint for set_page_dirty. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25f2fs: remove redundant set_page_dirty from write_compacted_summariesChao Yu
Previously, set_page_dirty is called every time after writting one summary info into compacted summary page, To avoid redundant set_page_dirty, we only call set_page_dirty before release page. Signed-off-by: Yu Chao <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25f2fs: add reclaiming control by sysfsJaegeuk Kim
This patch adds a control method in sysfs to reclaim prefree segments. Signed-off-by: Changman Lee <cm224.lee@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25f2fs: introduce f2fs_balance_fs_bg for some background jobsJaegeuk Kim
This patch merges some background jobs into this new function. Signed-off-by: Changman Lee <cm224.lee@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25f2fs: reclaim prefree segments periodicallyJaegeuk Kim
Previously, f2fs postpones reclaiming prefree segments into free segments as much as possible. However, if user writes and deletes a bunch of data without any sync or fsync calls, some flash storages can suffer from garbage collections. So, this patch adds the reclaiming codes to f2fs_write_node_pages and background GC thread. If there are a lot of prefree segments, let's do checkpoint so that f2fs submits discard commands for the prefree regions to the flash storage. Signed-off-by: Changman Lee <cm224.lee@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25f2fs: use bool for booleansHaicheng Li
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25f2fs: clean up several status-related operationsJaegeuk Kim
This patch cleans up improper definitions that update some status information. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25Merge tag 'ecryptfs-3.12-rc7-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs Pull ecryptfs fixes from Tyler Hicks: "Two important fixes - Fix long standing memory leak in the (rarely used) public key support - Fix large file corruption on 32 bit architectures" * tag 'ecryptfs-3.12-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs: eCryptfs: fix 32 bit corruption issue ecryptfs: Fix memory leakage in keystore.c
2013-10-25sysfs: fix sysfs_write_file for bin fileMing Lei
Before patch(sysfs: prepare path write for unified regular / bin file handling), when size of bin file is zero, writting still can continue, but this patch changes the behaviour. The worse thing is that firmware loader is broken by this patch, and user space application can't write to firmware bin file any more because both firmware loader and drivers can't know at advance how large the firmware file is and have to set its initialized size as zero. This patch fixes the problem and keeps behaviour of writting to bin as before. Reported-by: Lothar Waßmann <LW@karo-electronics.de> Tested-by: Lothar Waßmann <LW@karo-electronics.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-24fuse: rcu-delay freeing fuse_connAl Viro
makes ->permission() and ->d_revalidate() safety in RCU mode independent from vfsmount_lock. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24ncpfs: rcu-delay unload_nls() and freeing ncp_serverAl Viro
makes ->d_hash() and ->d_compare() safety in RCU mode independent from vfsmount_lock. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24fat: rcu-delay unloading nls and freeing sbiAl Viro
makes ->d_hash() and ->d_compare() safety in RCU mode independent from vfsmount_lock. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24cifs: rcu-delay unload_nls() and freeing sbiAl Viro
makes ->d_hash(), ->d_compare() and ->permission() safety in RCU mode independent from vfsmount_lock. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24autofs4: make freeing sbi rcu-delayedAl Viro
makes ->d_managed() safety in RCU mode independent from vfsmount_lock Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24adfs: delayed freeing of sbiAl Viro
makes ->d_hash() and ->d_compare() safety in RCU mode independent from vfsmount_lock. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24hpfs: make freeing sbi and codetables rcu-delayedAl Viro
makes ->d_hash() and ->d_compare() safety in RCU mode independent from vfsmount_lock Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24make freeing super_block rcu-delayedAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24vfs: introduce d_instantiate_no_diralias()Miklos Szeredi
...which just returns -EBUSY if a directory alias would be created. This is to be used by fuse mkdir to make sure that a buggy or malicious userspace filesystem doesn't do anything nasty. Previously fuse used a private mutex for this purpose, which can now go away. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-24move taking vfsmount_lock down into prepend_path()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24split __lookup_mnt() in two functionsAl Viro
Instead of passing the direction as argument (and checking it on every step through the hash chain), just have separate __lookup_mnt() and __lookup_mnt_last(). And use the standard iterators... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24uninline destroy_super(), consolidate alloc_super()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24isofs: don't pass dentry to isofs_hash{i,}_common()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24new helpers: lock_mount_hash/unlock_mount_hashAl Viro
aka br_write_{lock,unlock} of vfsmount_lock. Inlines in fs/mount.h, vfsmount_lock extern moved over there as well. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24don't bother with vfsmount_lock in mounts_poll()Al Viro
wake_up_interruptible/poll_wait provide sufficient barriers; just use ACCESS_ONCE() to fetch ns->event and that's it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>