Create a file to house all the rpc_pipefs boilerplate code instead of
sprinkling it over a few files.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Factor out a helper for all per-extent work, and merge the now trivial
functions for lseg allocation and parsing.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This isn't device(id) related, so move it into the main file. Simple move
for now, the next commit will clean it up a bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Instead of overflowing the XDR send buffer with our extent list allocate
pages and pre-encode the layoutupdate payload into them. We optimistically
allocate a single page use alloc_page and only switch to vmalloc when we
have more extents outstanding. Currently there is only a single testcase
(xfstests generic/113) which can reproduce large enough extent lists for
this to occur.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The current GETDEVICELIST implementation is buggy in that it doesn't handle
cursors correctly, and in that it returns an error if the server returns
NFSERR_NOTSUPP. Given that there is no actual need for GETDEVICELIST,
it has various issues and might get removed for NFSv4.2 stop using it in
the blocklayout driver, and thus the Linux NFS client as whole.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The kbuild test robot complained about a new sparse warning in
objio_alloc_deviceid_node, but it turns out that this was just a moved
reference to an existing variable. Fix it to have the right big endian
annotated type.
Note that there are some other endianess issues in this file that I didn't
bother to sort out as they involve global headers.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The kbuild test robot complained that we got the printk format wrong.
Let's just kill these printks instead of fixing them as there is not
point after the initial tree algorithm debugging.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
sparse says:
fs/nfs/file.c:543:60: warning: incorrect type in argument 1 (different address spaces)
fs/nfs/file.c:543:60: expected struct rpc_xprt *xprt
fs/nfs/file.c:543:60: got struct rpc_xprt [noderef] <asn:4>*cl_xprt
fs/nfs/file.c:548:53: warning: incorrect type in argument 1 (different address spaces)
fs/nfs/file.c:548:53: expected struct rpc_xprt *xprt
fs/nfs/file.c:548:53: got struct rpc_xprt [noderef] <asn:4>*cl_xprt
cl_xprt is RCU-managed, so we need to take care to dereference and use
it while holding the RCU read lock.
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The VFS never calls setattr with ATTR_SIZE on anything but regular
files. Remove the if check and turn it into an assert similar to
what some other file systems do.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This will be used by the block layout driver when splitting extents.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
At a simple helper to issue a GETDEVICELIST operation and pre-load
the device id cache based on the result.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Add support to the common pNFS core to issue GETDEVICEINFO calls on
a device ID cache miss. The code is taken from the well debugged
file layout implementation and calls out to the layoutdriver through
a new alloc_deviceid_node method. The calling conventions for
nfs4_find_get_deviceid are changed so that all information needed to
send a GETDEVICEINFO request is passed to the common code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This speads up truncate-heavy workloads like fsx by multiple orders of
magnitude.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This allows removing extents from the extent tree especially on truncate
operations, and thus fixing reads from truncated and re-extended that
previously returned stale data.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Currently the block layout driver tracks extents in three separate
data structures:
- the two list of pnfs_block_extent structures returned by the server
- the list of sectors that were in invalid state but have been written to
- a list of pnfs_block_short_extent structures for LAYOUTCOMMIT
All of these share the property that they are not only highly inefficient
data structures, but also that operations on them are even more inefficient
than nessecary.
In addition there are various implementation defects like:
- using an int to track sectors, causing corruption for large offsets
- incorrect normalization of page or block granularity ranges
- insufficient error handling
- incorrect synchronization as extents can be modified while they are in
use
This patch replace all three data with a single unified rbtree structure
tracking all extents, as well as their in-memory state, although we still
need to instance for read-only and read-write extent due to the arcane
client side COW feature in the block layouts spec.
To fix the problem of extent possibly being modified while in use we make
sure to return a copy of the extent for use in the write path - the
extent can only be invalidated by a layout recall or return which has
to wait until the I/O operations finished due to refcounts on the layout
segment.
The new extent tree work similar to the schemes used by block based
filesystems like XFS or ext4.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The core nfs code handles setting pages uptodate on reads, no need to mess
with the pageflags outselves. Also remove a debug function to dump page
flags.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Use the new PNFS_READ_WHOLE_PAGE flag to offload read-modify-write
handling to core nfs code, and remove a huge chunk of deadlock prone
mess from the block layout writeback path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If a layout driver keeps per-inode state outside of the layout segments it
needs to be notified of any layout returns or recalls on an inode, and not
just about the freeing of layout segments. Add a method to acomplish this,
which will allow the block layout driver to handle the case of truncated
and re-expanded files properly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Like all block based filesystems, the pNFS block layout driver can't read
or write at a byte granularity and thus has to perform read-modify-write
cycles on writes smaller than this granularity.
Add a flag so that the core NFS code always reads a whole page when
starting a smaller write, so that we can do it in the place where the VFS
expects it instead of doing in very deadlock prone way in the writeback
handler.
Note that in theory we could do less than page size reads here for disks
that have a smaller sector size which are served by a server with a smaller
pnfs block size. But so far that doesn't seem like a worthwhile
optimization.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Expedite layout recall processing by forcing a layout commit when
we see busy segments. Without it the layout recall might have to wait
until the VM decided to start writeback for the file, which can introduce
long delays.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
gcc reports:
linux/fs/nfs/write.c: In function ‘nfs_page_find_head_request_locked.isra.17’:
linux/fs/nfs/write.c:121:64: warning: ‘cinfo.mds’ may be used uninitialized in this function [-Wmaybe-uninitialized]
list_for_each_entry_safe(freq, t, &cinfo.mds->list, wb_list) {
^
linux/fs/nfs/write.c:110:25: note: ‘cinfo.mds’ was declared here
struct nfs_commit_info cinfo;
Reported-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Cc: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When we do non-page sized reads we can underflow the extent_length variable
and read incorrect data. Fix the extent_length calculation and change to
defensive <= checks for the extent length in the read and write path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Make sure the block queue is plugged when performing pNFS blocklayout I/O.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tell userspace what stage of GETDEVICEINFO failed so that there is a chance
to debug it, especially with the userspace daemon clusterf***k in the block
layout driver.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The Linux VM subsystem can't support block sizes larger than page size
for block based filesystems very well. While this can be hacked around
to some extent for simple filesystems the read-modify-write cycles
required for pnfs block invalid extents are extremly deadlock prone
when operating on multiple pages. Reject this case early on instead
of pretending to support it (badly).
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Currently there is no XDR buffer space allocated for the per-layout driver
layoutcommit payload, which leads to server buffer overflows in the
blocklayout driver even under simple workloads. As we can't do per-layout
sizes for XDR operations we'll have to splice a previously encoded list
of pages into the XDR stream, similar to how we handle ACL buffers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
After we issued a layoutreturn operations the may free the layout stateid
and will thus cause bad stateid error when the client uses it again.
We currently try to avoid this case by chosing the open stateid if not
lsegs are present for this inode. But various places can hold refererence
on lsegs and thus cause the list not to be empty shortly after a layout
return. Add an explicit flag to mark the current layout stateid invalid
and force usage of the openstateid after we did a full file layoutreturn.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Currently we fall through to nfs4_async_handle_error when we get
a bad stateid error back from layoutget. nfs4_async_handle_error
with a NULL state argument will never retry the operations but return
the error to higher layer, causing an avoiable fallback to MDS I/O.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When layoutget returns an entirely new layout stateid it should not
check the generation counter as the new stateid will start with a new
counter entirely unrelated to old one.
The current behavior causes constant layoutget failures against a block
server which allocates a new stateid after an recall that removed all
outstanding layouts.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Ensure the lsegs are initialized early so that we don't pass an unitialized
one back to ->free_lseg during error processing.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
pNFS servers may return arbitrarily large layouts. Trim back the I/O size
to one that we can at least allocate the page array for.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Following http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
Don't set layoutcommit for commit_through_mds case.
For FILE_SYNC writes, don't set layoutcommit.
For DATA_SYNC wirtes, set layout commit right after wirtes done.
For UNSTABLE writes, set layout commit when commit done.
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Track lwb in nfs_commit_data so that we can use it to setup
layoutcommit in commit_done callback.
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
can_open_cached() reads values out of the state structure, meaning that
we need the so_lock to have a correct return value. As a bonus, this
helps clear up some potentially confusing code.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
filelayout_retry_commit was recently split out from alloc_ds_commits,
but was done in such a way that the bucket pointer always starts at
index 0 no matter what the @idx argument is set to.
The intention of the @idx argument is to retry commits starting at
bucket @idx. This is called when alloc_ds_commits fails for a bucket.
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Pull filesystem fixes from Al Viro:
"Several bugfixes (all of them -stable fodder).
Alexey's one deals with double mutex_lock() in UFS (apparently, nobody
has tried to test "ufs: sb mutex merge + mutex_destroy" on something
like file creation/removal on ufs). Mine deal with two kinds of
umount bugs, in umount propagation and in handling of automounted
submounts, both resulting in bogus transient EBUSY from umount"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ufs: fix deadlocks introduced by sb mutex merge
fix EBUSY on umount() from MNT_SHRINKABLE
get rid of propagate_umount() mistakenly treating slaves as busy.
Commit 0244756edc ("ufs: sb mutex merge + mutex_destroy") introduces
deadlocks in ufs_new_inode() and ufs_free_inode().
Most callers of that functions acqure the mutex by themselves and
ufs_{new,free}_inode() do that via lock_ufs(),
i.e we have an unavoidable double lock.
The patch proposes to resolve the issue by making sure that
ufs_{new,free}_inode() are not called with the mutex held.
Found by Linux Driver Verification project (linuxtesting.org).
Cc: stable@vger.kernel.org # 3.16
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Fix:
- a direct IO read/buffered read data corruption
- the associated fallout from the DIO data corruption fix
- collapse range bugs that are potential data corruption issues.
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Merge tag 'xfs-for-linus-3.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
Pull xfs fixes from Dave Chinner:
"The fixes all address recently discovered data corruption issues.
The original Direct IO issue was discovered by Chris Mason @ Facebook
on a production workload which mixed buffered reads with direct reads
and writes IO to the same file. The fix for that exposed other issues
with page invalidation (exposed by millions of fsx operations) failing
due to dirty buffers beyond EOF.
Finally, the collapse_range code could also cause problems due to
racing writeback changing the extent map while it was being shifted
around. The commits for that problem are simple mitigation fixes that
prevent the problem from occuring. A more robust fix for 3.18 that
addresses the underlying problem is currently being worked on by
Brian.
Summary of fixes:
- a direct IO read/buffered read data corruption
- the associated fallout from the DIO data corruption fix
- collapse range bugs that are potential data corruption issues"
* tag 'xfs-for-linus-3.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs:
xfs: trim eofblocks before collapse range
xfs: xfs_file_collapse_range is delalloc challenged
xfs: don't log inode unless extent shift makes extent modifications
xfs: use ranged writeback and invalidation for direct IO
xfs: don't zero partial page cache pages during O_DIRECT writes
xfs: don't zero partial page cache pages during O_DIRECT writes
xfs: don't dirty buffers beyond EOF
This patch changes sync_filesystem() to be EXPORT_SYMBOL().
The reason this is needed is that starting with 3.15 kernel, due to
Theodore Ts'o's commit 02b9984d64 ("fs: push sync_filesystem() down to
the file system's remount_fs()"), all file systems that have dirty data
to be written out need to call sync_filesystem() from their
->remount_fs() method when remounting read-only.
As this is now a generically required function rather than an internal
only function it should be EXPORT_SYMBOL() so that all file systems can
call it.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull aio bugfixes from Ben LaHaise:
"Two small fixes"
* git://git.kvack.org/~bcrl/aio-fixes:
aio: block exit_aio() until all context requests are completed
aio: add missing smp_rmb() in read_events_ring
It seems that exit_aio() also needs to wait for all iocbs to complete (like
io_destroy), but we missed the wait step in current implemention, so fix
it in the same way as we did in io_destroy.
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Cc: stable@vger.kernel.org
Pull f2fs bug fixes from Jaegeuk Kim:
"This series includes patches to:
- fix recovery routines
- fix bugs related to inline_data/xattr
- fix when casting the dentry names
- handle EIO or ENOMEM correctly
- fix memory leak
- fix lock coverage"
* tag 'for-f2fs-3.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (28 commits)
f2fs: reposition unlock_new_inode to prevent accessing invalid inode
f2fs: fix wrong casting for dentry name
f2fs: simplify by using a literal
f2fs: truncate stale block for inline_data
f2fs: use macro for code readability
f2fs: introduce need_do_checkpoint for readability
f2fs: fix incorrect calculation with total/free inode num
f2fs: remove rename and use rename2
f2fs: skip if inline_data was converted already
f2fs: remove rewrite_node_page
f2fs: avoid double lock in truncate_blocks
f2fs: prevent checkpoint during roll-forward
f2fs: add WARN_ON in f2fs_bug_on
f2fs: handle EIO not to break fs consistency
f2fs: check s_dirty under cp_mutex
f2fs: unlock_page when node page is redirtied out
f2fs: introduce f2fs_cp_error for readability
f2fs: give a chance to mount again when encountering errors
f2fs: trigger release_dirty_inode in f2fs_put_super
f2fs: don't skip checkpoint if there is no dirty node pages
...
We ran into a case on ppc64 running mariadb where io_getevents would
return zeroed out I/O events. After adding instrumentation, it became
clear that there was some missing synchronization between reading the
tail pointer and the events themselves. This small patch fixes the
problem in testing.
Thanks to Zach for helping to look into this, and suggesting the fix.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Cc: stable@vger.kernel.org
As the race condition on the inode cache, following scenario can appear:
[Thread a] [Thread b]
->f2fs_mkdir
->f2fs_add_link
->__f2fs_add_link
->init_inode_metadata failed here
->gc_thread_func
->f2fs_gc
->do_garbage_collect
->gc_data_segment
->f2fs_iget
->iget_locked
->wait_on_inode
->unlock_new_inode
->move_data_page
->make_bad_inode
->iput
When we fail in create/symlink/mkdir/mknod/tmpfile, the new allocated inode
should be set as bad to avoid being accessed by other thread. But in above
scenario, it allows f2fs to access the invalid inode before this inode was set
as bad.
This patch fix the potential problem, and this issue was found by code review.
change log from v1:
o Add condition judgment in gc_data_segment() suggested by Changman Lee.
o use iget_failed to simplify code.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
xfs_collapse_file_space() currently writes back the entire file
undergoing collapse range to settle things down for the extent shift
algorithm. While this prevents changes to the extent list during the
collapse operation, the writeback itself is not enough to prevent
unnecessary collapse failures.
The current shift algorithm uses the extent index to iterate the in-core
extent list. If a post-eof delalloc extent persists after the writeback
(e.g., a prior zero range op where the end of the range aligns with eof
can separate the post-eof blocks such that they are not written back and
converted), xfs_bmap_shift_extents() becomes confused over the encoded
br_startblock value and fails the collapse.
As with the full writeback, this is a temporary fix until the algorithm
is improved to cope with a volatile extent list and avoid attempts to
shift post-eof extents.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
If we have delalloc extents on a file before we run a collapse range
opertaion, we sync the range that we are going to collapse to
convert delalloc extents in that region to real extents to simplify
the shift operation.
However, the shift operation then assumes that the extent list is
not going to change as it iterates over the extent list moving
things about. Unfortunately, this isn't true because we can't hold
the ILOCK over all the operations. We can prevent new IO from
modifying the extent list by holding the IOLOCK, but that doesn't
prevent writeback from running....
And when writeback runs, it can convert delalloc extents is the
range of the file prior to the region being collapsed, and this
changes the indexes of all the extents in the file. That causes the
collapse range operation to Go Bad.
The right fix is to rewrite the extent shift operation not to be
dependent on the extent list not changing across the entire
operation, but this is a fairly significant piece of work to do.
Hence, as a short-term workaround for the problem, sync the entire
file before starting a collapse operation to remove all delalloc
ranges from the file and so avoid the problem of concurrent
writeback changing the extent list.
Diagnosed-and-Reported-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
