Hightlights include:
Stable bugfixes:
- Fix mirror allocation in the writeback code to avoid a use after free
- Fix the O_DSYNC writes to use the correct byte range
- Fix 2 use after free issues in the I/O code
Features:
- Writeback fixes to split up the inode->i_lock in order to reduce contention
- RPC client receive fixes to reduce the amount of time the
xprt->transport_lock is held when receiving data from a socket into am
XDR buffer.
- Ditto fixes to reduce contention between call side users of the rdma
rb_lock, and its use in rpcrdma_reply_handler.
- Re-arrange rdma stats to reduce false cacheline sharing.
- Various rdma cleanups and optimisations.
- Refactor the NFSv4.1 exchange id code and clean up the code.
- Const-ify all instances of struct rpc_xprt_ops
Bugfixes:
- Fix the NFSv2 'sec=' mount option.
- NFSv4.1: don't use machine credentials for CLOSE when using 'sec=sys'
- Fix the NFSv3 GRANT callback when the port changes on the server.
- Fix livelock issues with COMMIT
- NFSv4: Use correct inode in _nfs4_opendata_to_nfs4_state() when doing
and NFSv4.1 open by filehandle.
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Merge tag 'nfs-for-4.14-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Hightlights include:
Stable bugfixes:
- Fix mirror allocation in the writeback code to avoid a use after
free
- Fix the O_DSYNC writes to use the correct byte range
- Fix 2 use after free issues in the I/O code
Features:
- Writeback fixes to split up the inode->i_lock in order to reduce
contention
- RPC client receive fixes to reduce the amount of time the
xprt->transport_lock is held when receiving data from a socket into
am XDR buffer.
- Ditto fixes to reduce contention between call side users of the
rdma rb_lock, and its use in rpcrdma_reply_handler.
- Re-arrange rdma stats to reduce false cacheline sharing.
- Various rdma cleanups and optimisations.
- Refactor the NFSv4.1 exchange id code and clean up the code.
- Const-ify all instances of struct rpc_xprt_ops
Bugfixes:
- Fix the NFSv2 'sec=' mount option.
- NFSv4.1: don't use machine credentials for CLOSE when using
'sec=sys'
- Fix the NFSv3 GRANT callback when the port changes on the server.
- Fix livelock issues with COMMIT
- NFSv4: Use correct inode in _nfs4_opendata_to_nfs4_state() when
doing and NFSv4.1 open by filehandle"
* tag 'nfs-for-4.14-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (69 commits)
NFS: Count the bytes of skipped subrequests in nfs_lock_and_join_requests()
NFS: Don't hold the group lock when calling nfs_release_request()
NFS: Remove pnfs_generic_transfer_commit_list()
NFS: nfs_lock_and_join_requests and nfs_scan_commit_list can deadlock
NFS: Fix 2 use after free issues in the I/O code
NFS: Sync the correct byte range during synchronous writes
lockd: Delete an error message for a failed memory allocation in reclaimer()
NFS: remove jiffies field from access cache
NFS: flush data when locking a file to ensure cache coherence for mmap.
SUNRPC: remove some dead code.
NFS: don't expect errors from mempool_alloc().
xprtrdma: Use xprt_pin_rqst in rpcrdma_reply_handler
xprtrdma: Re-arrange struct rx_stats
NFS: Fix NFSv2 security settings
NFSv4.1: don't use machine credentials for CLOSE when using 'sec=sys'
SUNRPC: ECONNREFUSED should cause a rebind.
NFS: Remove unused parameter gfp_flags from nfs_pageio_init()
NFSv4: Fix up mirror allocation
SUNRPC: Add a separate spinlock to protect the RPC request receive list
SUNRPC: Cleanup xs_tcp_read_common()
...
If we skip a subrequest due to a zero refcount, we should still count
the byte range that it covered so that we accurately reconstruct the
original request size.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
and a small cleanup to our xdr encoding.
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Merge tag 'nfsd-4.14' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"More RDMA work and some op-structure constification from Chuck Lever,
and a small cleanup to our xdr encoding"
* tag 'nfsd-4.14' of git://linux-nfs.org/~bfields/linux:
svcrdma: Estimate Send Queue depth properly
rdma core: Add rdma_rw_mr_payload()
svcrdma: Limit RQ depth
svcrdma: Populate tail iovec when receiving
nfsd: Incoming xdr_bufs may have content in tail buffer
svcrdma: Clean up svc_rdma_build_read_chunk()
sunrpc: Const-ify struct sv_serv_ops
nfsd: Const-ify NFSv4 encoding and decoding ops arrays
sunrpc: Const-ify instances of struct svc_xprt_ops
nfsd4: individual encoders no longer see error cases
nfsd4: skip encoder in trivial error cases
nfsd4: define ->op_release for compound ops
nfsd4: opdesc will be useful outside nfs4proc.c
nfsd4: move some nfsd4 op definitions to xdr4.h
That can deadlock if this is the last reference since
nfs_page_group_destroy() calls nfs_page_group_sync_on_bit().
Note that even if the page was removed from the subpage list,
the req->wb_head could still be pointing to the old head.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
It's pretty much a duplicate of nfs_scan_commit_list() that also
clears the PG_COMMIT_TO_DS flag.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Since the commit list is not ordered, it is possible for nfs_scan_commit_list
to hold a request that nfs_lock_and_join_requests() is waiting for, while
at the same time trying to grab a request that nfs_lock_and_join_requests
already holds.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The writeback code wants to send a commit after processing the pages,
which is why we want to delay releasing the struct path until after
that's done.
Also, the layout code expects that we do not free the inode before
we've put the layout segments in pnfs_writehdr_free() and
pnfs_readhdr_free()
Fixes: 919e3bd9a8 ("NFS: Ensure we commit after writeback is complete")
Fixes: 4714fb51fd ("nfs: remove pgio_header refcount, related cleanup")
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Pull block layer updates from Jens Axboe:
"This is the first pull request for 4.14, containing most of the code
changes. It's a quiet series this round, which I think we needed after
the churn of the last few series. This contains:
- Fix for a registration race in loop, from Anton Volkov.
- Overflow complaint fix from Arnd for DAC960.
- Series of drbd changes from the usual suspects.
- Conversion of the stec/skd driver to blk-mq. From Bart.
- A few BFQ improvements/fixes from Paolo.
- CFQ improvement from Ritesh, allowing idling for group idle.
- A few fixes found by Dan's smatch, courtesy of Dan.
- A warning fixup for a race between changing the IO scheduler and
device remova. From David Jeffery.
- A few nbd fixes from Josef.
- Support for cgroup info in blktrace, from Shaohua.
- Also from Shaohua, new features in the null_blk driver to allow it
to actually hold data, among other things.
- Various corner cases and error handling fixes from Weiping Zhang.
- Improvements to the IO stats tracking for blk-mq from me. Can
drastically improve performance for fast devices and/or big
machines.
- Series from Christoph removing bi_bdev as being needed for IO
submission, in preparation for nvme multipathing code.
- Series from Bart, including various cleanups and fixes for switch
fall through case complaints"
* 'for-4.14/block' of git://git.kernel.dk/linux-block: (162 commits)
kernfs: checking for IS_ERR() instead of NULL
drbd: remove BIOSET_NEED_RESCUER flag from drbd_{md_,}io_bio_set
drbd: Fix allyesconfig build, fix recent commit
drbd: switch from kmalloc() to kmalloc_array()
drbd: abort drbd_start_resync if there is no connection
drbd: move global variables to drbd namespace and make some static
drbd: rename "usermode_helper" to "drbd_usermode_helper"
drbd: fix race between handshake and admin disconnect/down
drbd: fix potential deadlock when trying to detach during handshake
drbd: A single dot should be put into a sequence.
drbd: fix rmmod cleanup, remove _all_ debugfs entries
drbd: Use setup_timer() instead of init_timer() to simplify the code.
drbd: fix potential get_ldev/put_ldev refcount imbalance during attach
drbd: new disk-option disable-write-same
drbd: Fix resource role for newly created resources in events2
drbd: mark symbols static where possible
drbd: Send P_NEG_ACK upon write error in protocol != C
drbd: add explicit plugging when submitting batches
drbd: change list_for_each_safe to while(list_first_entry_or_null)
drbd: introduce drbd_recv_header_maybe_unplug
...
Since commit 18290650b1 ("NFS: Move buffered I/O locking into
nfs_file_write()") nfs_file_write() has not flushed the correct byte
range during synchronous writes. generic_write_sync() expects that
iocb->ki_pos points to the right edge of the range rather than the
left edge.
To replicate the problem, open a file with O_DSYNC, have the client
write at increasing offsets, and then print the successful offsets.
Block port 2049 partway through that sequence, and observe that the
client application indicates successful writes in advance of what the
server received.
Fixes: 18290650b1 ("NFS: Move buffered I/O locking into nfs_file_write()")
Signed-off-by: Jacob Strauss <jsstraus@amazon.com>
Signed-off-by: Tarang Gupta <tarangg@amazon.com>
Tested-by: Tarang Gupta <tarangg@amazon.com>
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Patch series "Ranged pagevec lookup", v2.
In this series I make pagevec_lookup() update the index (to be
consistent with pagevec_lookup_tag() and also as a preparation for
ranged lookups), provide ranged variant of pagevec_lookup() and use it
in places where it makes sense. This not only removes some common code
but is also a measurable performance win for some use cases (see patch
4/10) where radix tree is sparse and searching & grabing of a page after
the end of the range has measurable overhead.
This patch (of 10):
The callback doesn't ever get called. Remove it.
Link: http://lkml.kernel.org/r/20170726114704.7626-2-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This field hasn't been used since commit 57b691819e ("NFS: Cache
access checks more aggressively").
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When a byte range lock (or flock) is taken out on an NFS file, the
validity of the cached data is checked and the inode is marked
NFS_INODE_INVALID_DATA. However the cached data isn't flushed from
the page cache.
This is sufficient for future read() requests or mmap() requests as
they call nfs_revalidate_mapping() which performs the flush if
necessary.
However an existing mapping is not affected. Accessing data through
that mapping will continue to return old data even though the inode is
marked NFS_INODE_INVALID_DATA.
This can easily be confirmed using the 'nfs' tool in
git://github.com/okirch/twopence-nfs.git
and running
nfs coherence FILENAME
on one client, and
nfs coherence -r FILENAME
on another client.
It appears that prior to Linux 2.6.0 this worked correctly.
However commit:
http://git.kernel.org/cgit/linux/kernel/git/history/history.git/commit/?id=ca9268fe3ddd075714005adecd4afbd7f9ab87d0
removed the call to inode_invalidate_pages() from nfs_zap_caches(). I
haven't tested this code, but inspection suggests that prior to this
commit, file locking would invalidate all inode pages.
This patch adds a call to nfs_revalidate_mapping() after a
successful SETLK so that invalid data is flushed. With this patch the
above test passes. To minimize impact (and possibly avoid a GETATTR
call) this only happens if the mapping might be mapped into
userspace.
Cc: Olaf Kirch <okir@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Close an attack vector by moving the arrays of per-server methods to
read-only memory.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This way we don't need a block_device structure to submit I/O. The
block_device has different life time rules from the gendisk and
request_queue and is usually only available when the block device node
is open. Other callers need to explicitly create one (e.g. the lightnvm
passthrough code, or the new nvme multipathing code).
For the actual I/O path all that we need is the gendisk, which exists
once per block device. But given that the block layer also does
partition remapping we additionally need a partition index, which is
used for said remapping in generic_make_request.
Note that all the block drivers generally want request_queue or
sometimes the gendisk, so this removes a layer of indirection all
over the stack.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For a while now any NFSv2 mount where sec= is specified uses
AUTH_NULL. If sec= is not specified, the mount uses AUTH_UNIX.
Commit e68fd7c807 ("mount: use sec= that was specified on the
command line") attempted to address a very similar problem with
NFSv3, and should have fixed this too, but it has a bug.
The MNTv1 MNT procedure does not return a list of security flavors,
so our client makes up a list containing just AUTH_NULL. This should
enable nfs_verify_authflavors() to assign the sec= specified flavor,
but instead, it incorrectly sets it to AUTH_NULL.
I expect this would also be a problem for any NFSv3 server whose
MNTv3 MNT procedure returned a security flavor list containing only
AUTH_NULL.
Fixes: e68fd7c807 ("mount: use sec= that was specified on ... ")
BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=310
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
An NFSv4.1 client might close a file after the user who opened it has
logged off. In this case the user's credentials may no longer be
valid, if they are e.g. kerberos credentials that have expired.
NFSv4.1 has a mechanism to allow the client to use machine credentials
to close a file. However due to a short-coming in the RFC, a CLOSE
with those credentials may not be possible if the file in question
isn't exported to the same security flavor - the required PUTFH must
be rejected when this is the case.
Specifically if a server and client support kerberos in general and
have used it to form a machine credential, but the file is only
exported to "sec=sys", a PUTFH with the machine credentials will fail,
so CLOSE is not possible.
As RPC_AUTH_UNIX (used by sec=sys) credentials can never expire, there
is no value in using the machine credential in place of them.
So in that case, just use the users credentials for CLOSE etc, as you would
in NFSv4.0
Signed-off-by: Neil Brown <neilb@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Now that the mirror allocation has been moved, the parameter can go.
Also remove the redundant symbol export.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
There are a number of callers of nfs_pageio_complete() that want to
continue using the nfs_pageio_descriptor without needing to call
nfs_pageio_init() again. Examples include nfs_pageio_resend() and
nfs_pageio_cond_complete().
The problem is that nfs_pageio_complete() also calls
nfs_pageio_cleanup_mirroring(), which frees up the array of mirrors.
This can lead to writeback errors, in the next call to
nfs_pageio_setup_mirroring().
Fix by simply moving the allocation of the mirrors to
nfs_pageio_setup_mirroring().
Link: https://bugzilla.kernel.org/show_bug.cgi?id=196709
Reported-by: JianhongYin <yin-jianhong@163.com>
Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If a request is on the commit list, but is locked, we will currently skip
it, which can lead to livelocking when the commit count doesn't reduce
to zero.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Now that we no longer hold the inode->i_lock when manipulating the
commit lists, it is safe to call pnfs_put_lseg() again.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Switch from using the inode->i_lock for this to avoid contention with
other metadata manipulation.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The commit lists can get very large, so using the inode->i_lock can
end up affecting general metadata performance.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Split out the 2 cases so that we can treat the locking differently.
The issue is that the locking in the pageswapcache cache is highly
linked to the commit list locking.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Hide the locking from nfs_lock_and_join_requests() so that we can
separate out the requirements for swapcache pages.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Fix up the test in nfs_page_group_covers_page(). The simplest implementation
is to check that we have a set of intersecting or contiguous subrequests
that connect page offset 0 to nfs_page_length(req->wb_page).
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
nfs_page_group_lock() is now always called with the 'nonblock'
parameter set to 'false'.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
At this point, we only expect ever to potentially see PG_REMOVE and
PG_TEARDOWN being set on the subrequests.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Since nfs_page_group_destroy() does not take any locks on the requests
to be freed, we need to ensure that we don't inadvertently free the
request in nfs_destroy_unlinked_subrequests() while the last reference
is being released elsewhere.
Do this by:
1) Taking a reference to the request unless it is already being freed
2) Checking (under the page group lock) if PG_TEARDOWN is already set before
freeing an unreferenced request in nfs_destroy_unlinked_subrequests()
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When locking the entire group in order to remove subrequests,
the locks are always taken in order, and with the page group
lock being taken after the page head is locked. The intention
is that:
1) The lock on the group head guarantees that requests may not
be removed from the group (although new entries could be appended
if we're not holding the group lock).
2) It is safe to drop and retake the page group lock while iterating
through the list, in particular when waiting for a subrequest lock.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
We should no longer need the inode->i_lock, now that we've
straightened out the request locking. The locking schema is now:
1) Lock page head request
2) Lock the page group
3) Lock the subrequests one by one
Note that there is a subtle race with nfs_inode_remove_request() due
to the fact that the latter does not lock the page head, when removing
it from the struct page. Only the last subrequest is locked, hence
we need to re-check that the PagePrivate(page) is still set after
we've locked all the subrequests.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Both nfs_destroy_unlinked_subrequests() and nfs_lock_and_join_requests()
manipulate the inode flags adjusting the NFS_I(inode)->nrequests.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
We don't want nfs_lock_and_join_requests() to start fiddling with
the request before the call to nfs_page_group_sync_on_bit().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Request offsets and sizes are not guaranteed to be stable unless you
are holding the request locked.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
All other callers of nfs_page_group_lock() appear to already hold the
page lock on the head page, so doing it in the opposite order here
is inefficient, although not deadlock prone since we roll back all
locks on contention.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Yes, this is a situation that should never happen (hence the WARN_ON)
but we should still ensure that we free up the locks and references to
the faulty pages.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This fixes a race with nfs_page_group_sync_on_bit() whereby the
call to wake_up_bit() in nfs_page_group_unlock() could occur after
the page header had been freed.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Add a lockless check for whether or not the page might be carrying
an existing writeback before we grab the inode->i_lock.
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
We don't expect the page header lock to ever be held across I/O, so
it should always be safe to wait for it, even if we're doing nonblocking
writebacks.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If we're recovering a nfs4_state, then we should try to use that instead
of looking up a new stateid. Only do that if the inodes match, though.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When doing open by filehandle we don't really want to lookup a new inode,
but rather update the one we've got. Add a helper which does this for us.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>