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2017-07-06Merge branch 'work.read_write' of ↵Linus Torvalds1-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull read/write updates from Al Viro: "Christoph's fs/read_write.c series - consolidation and cleanups" * 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: nfsd: remove nfsd_vfs_read nfsd: use vfs_iter_read/write fs: implement vfs_iter_write using do_iter_write fs: implement vfs_iter_read using do_iter_read fs: move more code into do_iter_read/do_iter_write fs: remove __do_readv_writev fs: remove do_compat_readv_writev fs: remove do_readv_writev
2017-06-30fs: implement vfs_iter_write using do_iter_writeChristoph Hellwig1-1/+1
De-dupliate some code and allow for passing the flags argument to vfs_iter_write. Additionally it now properly updates timestamps. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-30fs: implement vfs_iter_read using do_iter_readChristoph Hellwig1-2/+2
De-dupliate some code and allow for passing the flags argument to vfs_iter_read. Additional it properly updates atime now. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-18loop: Add PF_LESS_THROTTLE to block/loop device thread.NeilBrown1-1/+7
When a filesystem is mounted from a loop device, writes are throttled by balance_dirty_pages() twice: once when writing to the filesystem and once when the loop_handle_cmd() writes to the backing file. This double-throttling can trigger positive feedback loops that create significant delays. The throttling at the lower level is seen by the upper level as a slow device, so it throttles extra hard. The PF_LESS_THROTTLE flag was created to handle exactly this circumstance, though with an NFS filesystem mounted from a local NFS server. It reduces the throttling on the lower layer so that it can proceed largely unthrottled. To demonstrate this, create a filesystem on a loop device and write (e.g. with dd) several large files which combine to consume significantly more than the limit set by /proc/sys/vm/dirty_ratio or dirty_bytes. Measure the total time taken. When I do this directly on a device (no loop device) the total time for several runs (mkfs, mount, write 200 files, umount) is fairly stable: 28-35 seconds. When I do this over a loop device the times are much worse and less stable. 52-460 seconds. Half below 100seconds, half above. When I apply this patch, the times become stable again, though not as fast as the no-loop-back case: 53-72 seconds. There may be room for further improvement as the total overhead still seems too high, but this is a big improvement. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <tom.leiming@gmail.com> Suggested-by: Michal Hocko <mhocko@suse.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-12Merge tag 'v4.12-rc5' into for-4.13/blockJens Axboe1-0/+3
We've already got a few conflicts and upcoming work depends on some of the changes that have gone into mainline as regression fixes for this series. Pull in 4.12-rc5 to resolve these conflicts and make it easier on down stream trees to continue working on 4.13 changes. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-09blk-mq: switch ->queue_rq return value to blk_status_tChristoph Hellwig1-3/+3
Use the same values for use for request completion errors as the return value from ->queue_rq. BLK_STS_RESOURCE is special cased to cause a requeue, and all the others are completed as-is. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-09block: introduce new block status code typeChristoph Hellwig1-1/+1
Currently we use nornal Linux errno values in the block layer, and while we accept any error a few have overloaded magic meanings. This patch instead introduces a new blk_status_t value that holds block layer specific status codes and explicitly explains their meaning. Helpers to convert from and to the previous special meanings are provided for now, but I suspect we want to get rid of them in the long run - those drivers that have a errno input (e.g. networking) usually get errnos that don't know about the special block layer overloads, and similarly returning them to userspace will usually return somethings that strictly speaking isn't correct for file system operations, but that's left as an exercise for later. For now the set of errors is a very limited set that closely corresponds to the previous overloaded errno values, but there is some low hanging fruite to improve it. blk_status_t (ab)uses the sparse __bitwise annotations to allow for sparse typechecking, so that we can easily catch places passing the wrong values. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-09loop: fix error handling regressionArnd Bergmann1-1/+2
gcc points out an unusual indentation: drivers/block/loop.c: In function 'loop_set_status': drivers/block/loop.c:1149:3: error: this 'if' clause does not guard... [-Werror=misleading-indentation] if (figure_loop_size(lo, info->lo_offset, info->lo_sizelimit, ^~ drivers/block/loop.c:1152:4: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if' goto exit; This was introduced by a new feature that accidentally moved the opening braces from one condition to another. Adding a second pair of braces makes it work correctly again and also more readable. Fixes: f2c6df7dbf9a ("loop: support 4k physical blocksize") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-08loop: support 4k physical blocksizeHannes Reinecke1-6/+37
When generating bootable VM images certain systems (most notably s390x) require devices with 4k blocksize. This patch implements a new flag 'LO_FLAGS_BLOCKSIZE' which will set the physical blocksize to that of the underlying device, and allow to change the logical blocksize for up to the physical blocksize. Signed-off-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-08loop: Remove unused 'bdev' argument from loop_set_capacityHannes Reinecke1-2/+2
Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-08Fix loop device flush before configure v3James Wang1-0/+3
While installing SLES-12 (based on v4.4), I found that the installer will stall for 60+ seconds during LVM disk scan. The root cause was determined to be the removal of a bound device check in loop_flush() by commit b5dd2f6047ca ("block: loop: improve performance via blk-mq"). Restoring this check, examining ->lo_state as set by loop_set_fd() eliminates the bad behavior. Test method: modprobe loop max_loop=64 dd if=/dev/zero of=disk bs=512 count=200K for((i=0;i<4;i++))do losetup -f disk; done mkfs.ext4 -F /dev/loop0 for((i=0;i<4;i++))do mkdir t$i; mount /dev/loop$i t$i;done for f in `ls /dev/loop[0-9]*|sort`; do \ echo $f; dd if=$f of=/dev/null bs=512 count=1; \ done Test output: stock patched /dev/loop0 18.1217e-05 8.3842e-05 /dev/loop1 6.1114e-05 0.000147979 /dev/loop10 0.414701 0.000116564 /dev/loop11 0.7474 6.7942e-05 /dev/loop12 0.747986 8.9082e-05 /dev/loop13 0.746532 7.4799e-05 /dev/loop14 0.480041 9.3926e-05 /dev/loop15 1.26453 7.2522e-05 Note that from loop10 onward, the device is not mounted, yet the stock kernel consumes several orders of magnitude more wall time than it does for a mounted device. (Thanks for Mike Galbraith <efault@gmx.de>, give a changelog review.) Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: James Wang <jnwang@suse.com> Fixes: b5dd2f6047ca ("block: loop: improve performance via blk-mq") Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-02blk-mq: update ->init_request and ->exit_request prototypesChristoph Hellwig1-3/+2
Remove the request_idx parameter, which can't be used safely now that we support I/O schedulers with blk-mq. Except for a superflous check in mtip32xx it was unused anyway. Also pass the tag_set instead of just the driver data - this allows drivers to avoid some code duplication in a follow on cleanup. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20blk-mq: remove the error argument to blk_mq_complete_requestChristoph Hellwig1-2/+2
Now that all drivers that call blk_mq_complete_requests have a ->complete callback we can remove the direct call to blk_mq_end_request, as well as the error argument to blk_mq_complete_request. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20loop: zero-fill bio on the submitting cpuChristoph Hellwig1-16/+14
In thruth I've just audited which blk-mq drivers don't currently have a complete callback, but I think this change is at least borderline useful. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-08block: remove the discard_zeroes_data flagChristoph Hellwig1-2/+0
Now that we use the proper REQ_OP_WRITE_ZEROES operation everywhere we can kill this hack. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-08loop: implement REQ_OP_WRITE_ZEROESChristoph Hellwig1-0/+4
It's identical to discard as hole punches will always leave us with zeroes on reads. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-31blk-mq: constify struct blk_mq_opsEric Biggers1-1/+1
Constify all instances of blk_mq_ops, as they are never modified. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-03Merge branch 'rebased-statx' of ↵Linus Torvalds1-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs 'statx()' update from Al Viro. This adds the new extended stat() interface that internally subsumes our previous stat interfaces, and allows user mode to specify in more detail what kind of information it wants. It also allows for some explicit synchronization information to be passed to the filesystem, which can be relevant for network filesystems: is the cached value ok, or do you need open/close consistency, or what? From David Howells. Andreas Dilger points out that the first version of the extended statx interface was posted June 29, 2010: https://www.spinics.net/lists/linux-fsdevel/msg33831.html * 'rebased-statx' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: statx: Add a system call to make enhanced file info available
2017-03-03Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds1-7/+8
Pull block layer fixes from Jens Axboe: "A collection of fixes for this merge window, either fixes for existing issues, or parts that were waiting for acks to come in. This pull request contains: - Allocation of nvme queues on the right node from Shaohua. This was ready long before the merge window, but waiting on an ack from Bjorn on the PCI bit. Now that we have that, the three patches can go in. - Two fixes for blk-mq-sched with nvmeof, which uses hctx specific request allocations. This caused an oops. One part from Sagi, one part from Omar. - A loop partition scan deadlock fix from Omar, fixing a regression in this merge window. - A three-patch series from Keith, closing up a hole on clearing out requests on shutdown/resume. - A stable fix for nbd from Josef, fixing a leak of sockets. - Two fixes for a regression in this window from Jan, fixing a problem with one of his earlier patches dealing with queue vs bdi life times. - A fix for a regression with virtio-blk, causing an IO stall if scheduling is used. From me. - A fix for an io context lock ordering problem. From me" * 'for-linus' of git://git.kernel.dk/linux-block: block: Move bdi_unregister() to del_gendisk() blk-mq: ensure that bd->last is always set correctly block: don't call ioc_exit_icq() with the queue lock held for blk-mq block: Initialize bd_bdi on inode initialization loop: fix LO_FLAGS_PARTSCAN hang nvme: Complete all stuck requests blk-mq: Provide freeze queue timeout blk-mq: Export blk_mq_freeze_queue_wait nbd: stop leaking sockets blk-mq: move update of tags->rqs to __blk_mq_alloc_request() blk-mq: kill blk_mq_set_alloc_data() blk-mq: make blk_mq_alloc_request_hctx() allocate a scheduler request blk-mq-sched: Allocate sched reserved tags as specified in the original queue tagset nvme: allocate nvme_queue in correct node PCI: add an API to get node from vector blk-mq: allocate blk_mq_tags and requests in correct node
2017-03-03statx: Add a system call to make enhanced file info availableDavid Howells1-1/+2
Add a system call to make extended file information available, including file creation and some attribute flags where available through the underlying filesystem. The getattr inode operation is altered to take two additional arguments: a u32 request_mask and an unsigned int flags that indicate the synchronisation mode. This change is propagated to the vfs_getattr*() function. Functions like vfs_stat() are now inline wrappers around new functions vfs_statx() and vfs_statx_fd() to reduce stack usage. ======== OVERVIEW ======== The idea was initially proposed as a set of xattrs that could be retrieved with getxattr(), but the general preference proved to be for a new syscall with an extended stat structure. A number of requests were gathered for features to be included. The following have been included: (1) Make the fields a consistent size on all arches and make them large. (2) Spare space, request flags and information flags are provided for future expansion. (3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an __s64). (4) Creation time: The SMB protocol carries the creation time, which could be exported by Samba, which will in turn help CIFS make use of FS-Cache as that can be used for coherency data (stx_btime). This is also specified in NFSv4 as a recommended attribute and could be exported by NFSD [Steve French]. (5) Lightweight stat: Ask for just those details of interest, and allow a netfs (such as NFS) to approximate anything not of interest, possibly without going to the server [Trond Myklebust, Ulrich Drepper, Andreas Dilger] (AT_STATX_DONT_SYNC). (6) Heavyweight stat: Force a netfs to go to the server, even if it thinks its cached attributes are up to date [Trond Myklebust] (AT_STATX_FORCE_SYNC). And the following have been left out for future extension: (7) Data version number: Could be used by userspace NFS servers [Aneesh Kumar]. Can also be used to modify fill_post_wcc() in NFSD which retrieves i_version directly, but has just called vfs_getattr(). It could get it from the kstat struct if it used vfs_xgetattr() instead. (There's disagreement on the exact semantics of a single field, since not all filesystems do this the same way). (8) BSD stat compatibility: Including more fields from the BSD stat such as creation time (st_btime) and inode generation number (st_gen) [Jeremy Allison, Bernd Schubert]. (9) Inode generation number: Useful for FUSE and userspace NFS servers [Bernd Schubert]. (This was asked for but later deemed unnecessary with the open-by-handle capability available and caused disagreement as to whether it's a security hole or not). (10) Extra coherency data may be useful in making backups [Andreas Dilger]. (No particular data were offered, but things like last backup timestamp, the data version number and the DOS archive bit would come into this category). (11) Allow the filesystem to indicate what it can/cannot provide: A filesystem can now say it doesn't support a standard stat feature if that isn't available, so if, for instance, inode numbers or UIDs don't exist or are fabricated locally... (This requires a separate system call - I have an fsinfo() call idea for this). (12) Store a 16-byte volume ID in the superblock that can be returned in struct xstat [Steve French]. (Deferred to fsinfo). (13) Include granularity fields in the time data to indicate the granularity of each of the times (NFSv4 time_delta) [Steve French]. (Deferred to fsinfo). (14) FS_IOC_GETFLAGS value. These could be translated to BSD's st_flags. Note that the Linux IOC flags are a mess and filesystems such as Ext4 define flags that aren't in linux/fs.h, so translation in the kernel may be a necessity (or, possibly, we provide the filesystem type too). (Some attributes are made available in stx_attributes, but the general feeling was that the IOC flags were to ext[234]-specific and shouldn't be exposed through statx this way). (15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer, Michael Kerrisk]. (Deferred, probably to fsinfo. Finding out if there's an ACL or seclabal might require extra filesystem operations). (16) Femtosecond-resolution timestamps [Dave Chinner]. (A __reserved field has been left in the statx_timestamp struct for this - if there proves to be a need). (17) A set multiple attributes syscall to go with this. =============== NEW SYSTEM CALL =============== The new system call is: int ret = statx(int dfd, const char *filename, unsigned int flags, unsigned int mask, struct statx *buffer); The dfd, filename and flags parameters indicate the file to query, in a similar way to fstatat(). There is no equivalent of lstat() as that can be emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags. There is also no equivalent of fstat() as that can be emulated by passing a NULL filename to statx() with the fd of interest in dfd. Whether or not statx() synchronises the attributes with the backing store can be controlled by OR'ing a value into the flags argument (this typically only affects network filesystems): (1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this respect. (2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise its attributes with the server - which might require data writeback to occur to get the timestamps correct. (3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a network filesystem. The resulting values should be considered approximate. mask is a bitmask indicating the fields in struct statx that are of interest to the caller. The user should set this to STATX_BASIC_STATS to get the basic set returned by stat(). It should be noted that asking for more information may entail extra I/O operations. buffer points to the destination for the data. This must be 256 bytes in size. ====================== MAIN ATTRIBUTES RECORD ====================== The following structures are defined in which to return the main attribute set: struct statx_timestamp { __s64 tv_sec; __s32 tv_nsec; __s32 __reserved; }; struct statx { __u32 stx_mask; __u32 stx_blksize; __u64 stx_attributes; __u32 stx_nlink; __u32 stx_uid; __u32 stx_gid; __u16 stx_mode; __u16 __spare0[1]; __u64 stx_ino; __u64 stx_size; __u64 stx_blocks; __u64 __spare1[1]; struct statx_timestamp stx_atime; struct statx_timestamp stx_btime; struct statx_timestamp stx_ctime; struct statx_timestamp stx_mtime; __u32 stx_rdev_major; __u32 stx_rdev_minor; __u32 stx_dev_major; __u32 stx_dev_minor; __u64 __spare2[14]; }; The defined bits in request_mask and stx_mask are: STATX_TYPE Want/got stx_mode & S_IFMT STATX_MODE Want/got stx_mode & ~S_IFMT STATX_NLINK Want/got stx_nlink STATX_UID Want/got stx_uid STATX_GID Want/got stx_gid STATX_ATIME Want/got stx_atime{,_ns} STATX_MTIME Want/got stx_mtime{,_ns} STATX_CTIME Want/got stx_ctime{,_ns} STATX_INO Want/got stx_ino STATX_SIZE Want/got stx_size STATX_BLOCKS Want/got stx_blocks STATX_BASIC_STATS [The stuff in the normal stat struct] STATX_BTIME Want/got stx_btime{,_ns} STATX_ALL [All currently available stuff] stx_btime is the file creation time, stx_mask is a bitmask indicating the data provided and __spares*[] are where as-yet undefined fields can be placed. Time fields are structures with separate seconds and nanoseconds fields plus a reserved field in case we want to add even finer resolution. Note that times will be negative if before 1970; in such a case, the nanosecond fields will also be negative if not zero. The bits defined in the stx_attributes field convey information about a file, how it is accessed, where it is and what it does. The following attributes map to FS_*_FL flags and are the same numerical value: STATX_ATTR_COMPRESSED File is compressed by the fs STATX_ATTR_IMMUTABLE File is marked immutable STATX_ATTR_APPEND File is append-only STATX_ATTR_NODUMP File is not to be dumped STATX_ATTR_ENCRYPTED File requires key to decrypt in fs Within the kernel, the supported flags are listed by: KSTAT_ATTR_FS_IOC_FLAGS [Are any other IOC flags of sufficient general interest to be exposed through this interface?] New flags include: STATX_ATTR_AUTOMOUNT Object is an automount trigger These are for the use of GUI tools that might want to mark files specially, depending on what they are. Fields in struct statx come in a number of classes: (0) stx_dev_*, stx_blksize. These are local system information and are always available. (1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino, stx_size, stx_blocks. These will be returned whether the caller asks for them or not. The corresponding bits in stx_mask will be set to indicate whether they actually have valid values. If the caller didn't ask for them, then they may be approximated. For example, NFS won't waste any time updating them from the server, unless as a byproduct of updating something requested. If the values don't actually exist for the underlying object (such as UID or GID on a DOS file), then the bit won't be set in the stx_mask, even if the caller asked for the value. In such a case, the returned value will be a fabrication. Note that there are instances where the type might not be valid, for instance Windows reparse points. (2) stx_rdev_*. This will be set only if stx_mode indicates we're looking at a blockdev or a chardev, otherwise will be 0. (3) stx_btime. Similar to (1), except this will be set to 0 if it doesn't exist. ======= TESTING ======= The following test program can be used to test the statx system call: samples/statx/test-statx.c Just compile and run, passing it paths to the files you want to examine. The file is built automatically if CONFIG_SAMPLES is enabled. Here's some example output. Firstly, an NFS directory that crosses to another FSID. Note that the AUTOMOUNT attribute is set because transiting this directory will cause d_automount to be invoked by the VFS. [root@andromeda ~]# /tmp/test-statx -A /warthog/data statx(/warthog/data) = 0 results=7ff Size: 4096 Blocks: 8 IO Block: 1048576 directory Device: 00:26 Inode: 1703937 Links: 125 Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041 Access: 2016-11-24 09:02:12.219699527+0000 Modify: 2016-11-17 10:44:36.225653653+0000 Change: 2016-11-17 10:44:36.225653653+0000 Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------) Secondly, the result of automounting on that directory. [root@andromeda ~]# /tmp/test-statx /warthog/data statx(/warthog/data) = 0 results=7ff Size: 4096 Blocks: 8 IO Block: 1048576 directory Device: 00:27 Inode: 2 Links: 125 Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041 Access: 2016-11-24 09:02:12.219699527+0000 Modify: 2016-11-17 10:44:36.225653653+0000 Change: 2016-11-17 10:44:36.225653653+0000 Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-03-03Merge branch 'for-linus' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile two from Al Viro: - orangefs fix - series of fs/namei.c cleanups from me - VFS stuff coming from overlayfs tree * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: orangefs: Use RCU for destroy_inode vfs: use helper for calling f_op->fsync() mm: use helper for calling f_op->mmap() vfs: use helpers for calling f_op->{read,write}_iter() vfs: pass type instead of fn to do_{loop,iter}_readv_writev() vfs: extract common parts of {compat_,}do_readv_writev() vfs: wrap write f_ops with file_{start,end}_write() vfs: deny copy_file_range() for non regular files vfs: deny fallocate() on directory vfs: create vfs helper vfs_tmpfile() namei.c: split unlazy_walk() namei.c: fold the check for DCACHE_OP_REVALIDATE into d_revalidate() lookup_fast(): clean up the logics around the fallback to non-rcu mode namei: fold unlazy_link() into its sole caller
2017-03-02loop: fix LO_FLAGS_PARTSCAN hangOmar Sandoval1-7/+8
loop_reread_partitions() needs to do I/O, but we just froze the queue, so we end up waiting forever. This can easily be reproduced with losetup -P. Fix it by moving the reread to after we unfreeze the queue. Fixes: ecdd09597a57 ("block/loop: fix race between I/O and set_status") Reported-by: Tejun Heo <tj@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-02Merge remote-tracking branch 'ovl/for-viro' into for-linusAl Viro1-2/+2
Overlayfs-related series from Miklos and Amir
2017-02-28scripts/spelling.txt: add "algined" pattern and fix typo instancesMasahiro Yamada1-1/+1
Fix typos and add the following to the scripts/spelling.txt: algined||aligned While we are here, fix the "appplication" in the touched line in drivers/block/loop.c. Also, fix the "may not naturally ..." to "may not be naturally ..." in the touched line in mm/page_alloc. Link: http://lkml.kernel.org/r/1481573103-11329-9-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-20vfs: use helpers for calling f_op->{read,write}_iter()Miklos Szeredi1-2/+2
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2017-02-13block/loop: fix race between I/O and set_statusMing Lei1-5/+12
Inside set_status, transfer need to setup again, so we have to drain IO before the transition, otherwise oops may be triggered like the following: divide error: 0000 [#1] SMP KASAN CPU: 0 PID: 2935 Comm: loop7 Not tainted 4.10.0-rc7+ #213 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 task: ffff88006ba1e840 task.stack: ffff880067338000 RIP: 0010:transfer_xor+0x1d1/0x440 drivers/block/loop.c:110 RSP: 0018:ffff88006733f108 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff8800688d7000 RCX: 0000000000000059 RDX: 0000000000000000 RSI: 1ffff1000d743f43 RDI: ffff880068891c08 RBP: ffff88006733f160 R08: ffff8800688d7001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8800688d7000 R13: ffff880067b7d000 R14: dffffc0000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88006d000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000006c17e0 CR3: 0000000066e3b000 CR4: 00000000001406f0 Call Trace: lo_do_transfer drivers/block/loop.c:251 [inline] lo_read_transfer drivers/block/loop.c:392 [inline] do_req_filebacked drivers/block/loop.c:541 [inline] loop_handle_cmd drivers/block/loop.c:1677 [inline] loop_queue_work+0xda0/0x49b0 drivers/block/loop.c:1689 kthread_worker_fn+0x4c3/0xa30 kernel/kthread.c:630 kthread+0x326/0x3f0 kernel/kthread.c:227 ret_from_fork+0x31/0x40 arch/x86/entry/entry_64.S:430 Code: 03 83 e2 07 41 29 df 42 0f b6 04 30 4d 8d 44 24 01 38 d0 7f 08 84 c0 0f 85 62 02 00 00 44 89 f8 41 0f b6 48 ff 25 ff 01 00 00 99 <f7> 7d c8 48 63 d2 48 03 55 d0 48 89 d0 48 89 d7 48 c1 e8 03 83 RIP: transfer_xor+0x1d1/0x440 drivers/block/loop.c:110 RSP: ffff88006733f108 ---[ end trace 0166f7bd3b0c0933 ]--- Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: stable@vger.kernel.org Signed-off-by: Ming Lei <tom.leiming@gmail.com> Tested-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-12-24Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds1-1/+1
This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-15loop: return proper error from loop_queue_rq()Omar Sandoval1-1/+1
->queue_rq() should return one of the BLK_MQ_RQ_QUEUE_* constants, not an errno. f4aa4c7bbac6 ("block: loop: convert to per-device workqueue") Signed-off-by: Omar Sandoval <osandov@fb.com> Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@fb.com>
2016-10-12kthread: kthread worker API cleanupPetr Mladek1-4/+4
A good practice is to prefix the names of functions by the name of the subsystem. The kthread worker API is a mix of classic kthreads and workqueues. Each worker has a dedicated kthread. It runs a generic function that process queued works. It is implemented as part of the kthread subsystem. This patch renames the existing kthread worker API to use the corresponding name from the workqueues API prefixed by kthread_: __init_kthread_worker() -> __kthread_init_worker() init_kthread_worker() -> kthread_init_worker() init_kthread_work() -> kthread_init_work() insert_kthread_work() -> kthread_insert_work() queue_kthread_work() -> kthread_queue_work() flush_kthread_work() -> kthread_flush_work() flush_kthread_worker() -> kthread_flush_worker() Note that the names of DEFINE_KTHREAD_WORK*() macros stay as they are. It is common that the "DEFINE_" prefix has precedence over the subsystem names. Note that INIT() macros and init() functions use different naming scheme. There is no good solution. There are several reasons for this solution: + "init" in the function names stands for the verb "initialize" aka "initialize worker". While "INIT" in the macro names stands for the noun "INITIALIZER" aka "worker initializer". + INIT() macros are used only in DEFINE() macros + init() functions are used close to the other kthread() functions. It looks much better if all the functions use the same scheme. + There will be also kthread_destroy_worker() that will be used close to kthread_cancel_work(). It is related to the init() function. Again it looks better if all functions use the same naming scheme. + there are several precedents for such init() function names, e.g. amd_iommu_init_device(), free_area_init_node(), jump_label_init_type(), regmap_init_mmio_clk(), + It is not an argument but it was inconsistent even before. [arnd@arndb.de: fix linux-next merge conflict] Link: http://lkml.kernel.org/r/20160908135724.1311726-1-arnd@arndb.de Link: http://lkml.kernel.org/r/1470754545-17632-3-git-send-email-pmladek@suse.com Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Petr Mladek <pmladek@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Borislav Petkov <bp@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-15blk-mq: remove ->map_queueChristoph Hellwig1-1/+0
All drivers use the default, so provide an inline version of it. If we ever need other queue mapping we can add an optional method back, although supporting will also require major changes to the queue setup code. This provides better code generation, and better debugability as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-04loop: make do_req_filebacked more robustChristoph Hellwig1-33/+22
Use a switch statement to iterate over the possible operations and error out if it's an incorrect one. Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-04loop: don't try to use AIO for discardsChristoph Hellwig1-4/+8
Fix a fat-fingered conversion to the req_op accessors, and also use a switch statement to make it more obvious what is being checked. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Dave Chinner <david@fromorbit.com> Fixes: c2df40 ("drivers: use req op accessor"); Reviewed-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-07-13loop: Make user notify for adding loop device failedMinfei Huang1-0/+1
There is no error number returned if loop driver fails in function alloc_disk to add new loop device. Add a correct error number to make user notify in this case. Signed-off-by: Minfei Huang <mnghuan@gmail.com> Reviewed-by: Ming Lei <tom.leiming@gmail.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-07block, drivers: add REQ_OP_FLUSH operationMike Christie1-2/+2
This adds a REQ_OP_FLUSH operation that is sent to request_fn based drivers by the block layer's flush code, instead of sending requests with the request->cmd_flags REQ_FLUSH bit set. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-07drivers: use req op accessorMike Christie1-3/+3
The req operation REQ_OP is separated from the rq_flag_bits definition. This converts the block layer drivers to use req_op to get the op from the request struct. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-07block, drivers, cgroup: use op_is_write helper instead of checking for REQ_WRITEMike Christie1-3/+3
We currently set REQ_WRITE/WRITE for all non READ IOs like discard, flush, writesame, etc. In the next patches where we no longer set up the op as a bitmap, we will not be able to detect a operation direction like writesame by testing if REQ_WRITE is set. This patch converts the drivers and cgroup to use the op_is_write helper. This should just cover the simple cases. I did dm, md and bcache in their own patches because they were more involved. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-18Merge branch 'for-4.7/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+1
Pull block driver updates from Jens Axboe: "On top of the core pull request, this is the drivers pull request for this merge window. This contains: - Switch drivers to the new write back cache API, and kill off the flush flags. From me. - Kill the discard support for the STEC pci-e flash driver. It's trivially broken, and apparently unmaintained, so it's safer to just remove it. From Jeff Moyer. - A set of lightnvm updates from the usual suspects (Matias/Javier, and Simon), and fixes from Arnd, Jeff Mahoney, Sagi, and Wenwei Tao. - A set of updates for NVMe: - Turn the controller state management into a proper state machine. From Christoph. - Shuffling of code in preparation for NVMe-over-fabrics, also from Christoph. - Cleanup of the command prep part from Ming Lin. - Rewrite of the discard support from Ming Lin. - Deadlock fix for namespace removal from Ming Lin. - Use the now exported blk-mq tag helper for IO termination. From Sagi. - Various little fixes from Christoph, Guilherme, Keith, Ming Lin, Wang Sheng-Hui. - Convert mtip32xx to use the now exported blk-mq tag iter function, from Keith" * 'for-4.7/drivers' of git://git.kernel.dk/linux-block: (74 commits) lightnvm: reserved space calculation incorrect lightnvm: rename nr_pages to nr_ppas on nvm_rq lightnvm: add is_cached entry to struct ppa_addr lightnvm: expose gennvm_mark_blk to targets lightnvm: remove mgt targets on mgt removal lightnvm: pass dma address to hardware rather than pointer lightnvm: do not assume sequential lun alloc. nvme/lightnvm: Log using the ctrl named device lightnvm: rename dma helper functions lightnvm: enable metadata to be sent to device lightnvm: do not free unused metadata on rrpc lightnvm: fix out of bound ppa lun id on bb tbl lightnvm: refactor set_bb_tbl for accepting ppa list lightnvm: move responsibility for bad blk mgmt to target lightnvm: make nvm_set_rqd_ppalist() aware of vblks lightnvm: remove struct factory_blks lightnvm: refactor device ops->get_bb_tbl() lightnvm: introduce nvm_for_each_lun_ppa() macro lightnvm: refactor dev->online_target to global nvm_targets lightnvm: rename nvm_targets to nvm_tgt_type ...
2016-04-15block: loop: fix filesystem corruption in case of aio/dioMing Lei1-0/+6
Starting from commit e36f620428(block: split bios to max possible length), block core starts to split bio in the middle of bvec. Unfortunately loop dio/aio doesn't consider this situation, and always treat 'iter.iov_offset' as zero. Then filesystem corruption is observed. This patch figures out the offset of the base bvevc via 'bio->bi_iter.bi_bvec_done' and fixes the issue by passing the offset to iov iterator. Fixes: e36f6204288088f (block: split bios to max possible length) Cc: Keith Busch <keith.busch@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: stable@vger.kernel.org (4.5) Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-04-13loop: switch to using blk_queue_write_cache()Jens Axboe1-1/+1
Signed-off-by: Jens Axboe <axboe@fb.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2015-10-09Merge branch 'for-4.4/core' into for-4.4/driversJens Axboe1-8/+6
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-10-01blk-mq: fix racy updates of rq->errorsChristoph Hellwig1-6/+5
blk_mq_complete_request may be a no-op if the request has already been completed by others means (e.g. a timeout or cancellation), but currently drivers have to set rq->errors before calling blk_mq_complete_request, which might leave us with the wrong error value. Add an error parameter to blk_mq_complete_request so that we can defer setting rq->errors until we known we won the race to complete the request. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-09-23block: loop: support DIO & AIOMing Lei1-3/+95
There are at least 3 advantages to use direct I/O and AIO on read/write loop's backing file: 1) double cache can be avoided, then memory usage gets decreased a lot 2) not like user space direct I/O, there isn't cost of pinning pages 3) avoid context switch for obtaining good throughput - in buffered file read, random I/O top throughput is often obtained only if they are submitted concurrently from lots of tasks; but for sequential I/O, most of times they can be hit from page cache, so concurrent submissions often introduce unnecessary context switch and can't improve throughput much. There was such discussion[1] to use non-blocking I/O to improve the problem for application. - with direct I/O and AIO, concurrent submissions can be avoided and random read throughput can't be affected meantime xfstests(-g auto, ext4) is basically passed when running with direct I/O(aio), one exception is generic/232, but it failed in loop buffered I/O(4.2-rc6-next-20150814) too. Follows the fio test result for performance purpose: 4 jobs fio test inside ext4 file system over loop block 1) How to run - KVM: 4 VCPUs, 2G RAM - linux kernel: 4.2-rc6-next-20150814(base) with the patchset - the loop block is over one image on SSD. - linux psync, 4 jobs, size 1500M, ext4 over loop block - test result: IOPS from fio output 2) Throughput(IOPS) becomes a bit better with direct I/O(aio) ------------------------------------------------------------- test cases |randread |read |randwrite |write | ------------------------------------------------------------- base |8015 |113811 |67442 |106978 ------------------------------------------------------------- base+loop aio |8136 |125040 |67811 |111376 ------------------------------------------------------------- - somehow, it should be caused by more page cache avaiable for application or one extra page copy is avoided in case of direct I/O 3) context switch - context switch decreased by ~50% with loop direct I/O(aio) compared with loop buffered I/O(4.2-rc6-next-20150814) 4) memory usage from /proc/meminfo ------------------------------------------------------------- | Buffers | Cached ------------------------------------------------------------- base | > 760MB | ~950MB ------------------------------------------------------------- base+loop direct I/O(aio) | < 5MB | ~1.6GB ------------------------------------------------------------- - so there are much more page caches available for application with direct I/O [1] https://lwn.net/Articles/612483/ Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-09-23block: loop: introduce ioctl command of LOOP_SET_DIRECT_IOMing Lei1-0/+19
If loop block is mounted via 'mount -o loop', it isn't easy to pass file descriptor opened as O_DIRECT, so this patch introduces a new command to support direct IO for this case. Cc: linux-api@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-09-23block: loop: prepare for supporing direct IOMing Lei1-0/+77
This patches provides one interface for enabling direct IO from user space: - userspace(such as losetup) can pass 'file' which is opened/fcntl as O_DIRECT Also __loop_update_dio() is introduced to check if direct I/O can be used on current loop setting. The last big change is to introduce LO_FLAGS_DIRECT_IO flag for userspace to know if direct IO is used to access backing file. Cc: linux-api@vger.kernel.org Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-09-23block: loop: use kthread_workMing Lei1-55/+24
The following patch will use dio/aio to submit IO to backing file, then it needn't to schedule IO concurrently from work, so use kthread_work for decreasing context switch cost a lot. For non-AIO case, single thread has been used for long long time, and it was just converted to work in v4.0, which has caused performance regression for fedora live booting already. In discussion[1], even though submitting I/O via work concurrently can improve random read IO throughput, meantime it might hurt sequential read IO performance, so better to restore to single thread behaviour. For the following AIO support, it is better to use multi hw-queue with per-hwq kthread than current work approach suppose there is so high performance requirement for loop. [1] http://marc.info/?t=143082678400002&r=1&w=2 Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-09-23block: loop: set QUEUE_FLAG_NOMERGES for request queue of loopMing Lei1-0/+6
It doesn't make sense to enable merge because the I/O submitted to backing file is handled page by page. Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-17block: have drivers use blk_queue_max_discard_sectors()Jens Axboe1-2/+2
Some drivers use it now, others just set the limits field manually. But in preparation for splitting this into a hard and soft limit, ensure that they all call the proper function for setting the hw limit for discards. Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-05Merge branch 'for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more vfs updates from Al Viro: "Assorted VFS fixes and related cleanups (IMO the most interesting in that part are f_path-related things and Eric's descriptor-related stuff). UFS regression fixes (it got broken last cycle). 9P fixes. fs-cache series, DAX patches, Jan's file_remove_suid() work" [ I'd say this is much more than "fixes and related cleanups". The file_table locking rule change by Eric Dumazet is a rather big and fundamental update even if the patch isn't huge. - Linus ] * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits) 9p: cope with bogus responses from server in p9_client_{read,write} p9_client_write(): avoid double p9_free_req() 9p: forgetting to cancel request on interrupted zero-copy RPC dax: bdev_direct_access() may sleep block: Add support for DAX reads/writes to block devices dax: Use copy_from_iter_nocache dax: Add block size note to documentation fs/file.c: __fget() and dup2() atomicity rules fs/file.c: don't acquire files->file_lock in fd_install() fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation vfs: avoid creation of inode number 0 in get_next_ino namei: make set_root_rcu() return void make simple_positive() public ufs: use dir_pages instead of ufs_dir_pages() pagemap.h: move dir_pages() over there remove the pointless include of lglock.h fs: cleanup slight list_entry abuse xfs: Correctly lock inode when removing suid and file capabilities fs: Call security_ops->inode_killpriv on truncate fs: Provide function telling whether file_remove_privs() will do anything ...
2015-06-26Merge branch 'for-4.2/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds1-30/+52
Pull block driver updates from Jens Axboe: "This contains: - a few race fixes for null_blk, from Akinobu Mita. - a series of fixes for mtip32xx, from Asai Thambi and Selvan Mani at Micron. - NVMe: * Fix for missing error return on allocation failure, from Axel Lin. * Code consolidation and cleanups from Christoph. * Memory barrier addition, syncing queue count and queue pointers. From Jon Derrick. * Various fixes from Keith, an addition to support user issue reset from sysfs or ioctl, and automatic namespace rescan. * Fix from Matias, avoiding losing some request flags when marking the request failfast. - small cleanups and sparse fixups for ps3vram. From Geert Uytterhoeven and Geoff Lavand. - s390/dasd dead code removal, from Jarod Wilson. - a set of fixes and optimizations for loop, from Ming Lei. - conversion to blkdev_reread_part() of loop, dasd, ndb. From Ming Lei. - updates to cciss. From Tomas Henzl" * 'for-4.2/drivers' of git://git.kernel.dk/linux-block: (44 commits) mtip32xx: Fix accessing freed memory block: nvme-scsi: Catch kcalloc failure NVMe: Fix IO for extended metadata formats nvme: don't overwrite req->cmd_flags on sync cmd mtip32xx: increase wait time for hba reset mtip32xx: fix minor number mtip32xx: remove unnecessary sleep in mtip_ftl_rebuild_poll() mtip32xx: fix crash on surprise removal of the drive mtip32xx: Abort I/O during secure erase operation mtip32xx: fix incorrectly setting MTIP_DDF_SEC_LOCK_BIT mtip32xx: remove unused variable 'port->allocated' mtip32xx: fix rmmod issue MAINTAINERS: Update ps3vram block driver block/ps3vram: Remove obsolete reference to MTD block/ps3vram: Fix sparse warnings NVMe: Automatic namespace rescan NVMe: Memory barrier before queue_count is incremented NVMe: add sysfs and ioctl controller reset null_blk: restart request processing on completion handler null_blk: prevent timer handler running on a different CPU where started ...
2015-06-24vfs: add file_path() helperMiklos Szeredi1-1/+1
Turn d_path(&file->f_path, ...); into file_path(file, ...); Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>