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>
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>
Omit an extra message for a memory allocation failure in this function.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
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>
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>
Stable fix:
- Fix leaking nfs4_ff_ds_version array
Other fixes:
- Improve TEST_STATEID OLD_STATEID handling to prevent recovery loop
- Require 64-bit sector_t for pNFS blocklayout to prevent 32-bit compile
errors
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Merge tag 'nfs-for-4.13-5' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client fixes from Anna Schumaker:
"A few more NFS client bugfixes from me for rc5.
Dros has a stable fix for flexfiles to prevent leaking the
nfs4_ff_ds_version arrays when freeing a layout, Trond fixed a
potential recovery loop situation with the TEST_STATEID operation, and
Christoph fixed up the pNFS blocklayout Kconfig options to prevent
unsafe use with kernels that don't have large block device support.
Summary:
Stable fix:
- fix leaking nfs4_ff_ds_version array
Other fixes:
- improve TEST_STATEID OLD_STATEID handling to prevent recovery loop
- require 64-bit sector_t for pNFS blocklayout to prevent 32-bit
compile errors"
* tag 'nfs-for-4.13-5' of git://git.linux-nfs.org/projects/anna/linux-nfs:
pnfs/blocklayout: require 64-bit sector_t
NFSv4: Ignore NFS4ERR_OLD_STATEID in nfs41_check_open_stateid()
nfs/flexfiles: fix leak of nfs4_ff_ds_version arrays
Pull fuse fixes from Miklos Szeredi:
"Fix a few bugs in fuse"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
fuse: set mapping error in writepage_locked when it fails
fuse: Dont call set_page_dirty_lock() for ITER_BVEC pages for async_dio
fuse: initialize the flock flag in fuse_file on allocation
The blocklayout code does not compile cleanly for a 32-bit sector_t,
and also has no reliable checks for devices sizes, which makes it
unsafe to use with a kernel that doesn't support large block devices.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 5c83746a0c ("pnfs/blocklayout: in-kernel GETDEVICEINFO XDR parsing")
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This ensures that we see errors on fsync when writeback fails.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
When the process exit races with outstanding mcopy_atomic, it would be
better to return ESRCH error. When such race occurs the process and
it's mm are going away and returning "no such process" to the uffd
monitor seems better fit than ENOSPC.
Link: http://lkml.kernel.org/r/1502111545-32305-1-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nadav reported KSM can corrupt the user data by the TLB batching
race[1]. That means data user written can be lost.
Quote from Nadav Amit:
"For this race we need 4 CPUs:
CPU0: Caches a writable and dirty PTE entry, and uses the stale value
for write later.
CPU1: Runs madvise_free on the range that includes the PTE. It would
clear the dirty-bit. It batches TLB flushes.
CPU2: Writes 4 to /proc/PID/clear_refs , clearing the PTEs soft-dirty.
We care about the fact that it clears the PTE write-bit, and of
course, batches TLB flushes.
CPU3: Runs KSM. Our purpose is to pass the following test in
write_protect_page():
if (pte_write(*pvmw.pte) || pte_dirty(*pvmw.pte) ||
(pte_protnone(*pvmw.pte) && pte_savedwrite(*pvmw.pte)))
Since it will avoid TLB flush. And we want to do it while the PTE is
stale. Later, and before replacing the page, we would be able to
change the page.
Note that all the operations the CPU1-3 perform canhappen in parallel
since they only acquire mmap_sem for read.
We start with two identical pages. Everything below regards the same
page/PTE.
CPU0 CPU1 CPU2 CPU3
---- ---- ---- ----
Write the same
value on page
[cache PTE as
dirty in TLB]
MADV_FREE
pte_mkclean()
4 > clear_refs
pte_wrprotect()
write_protect_page()
[ success, no flush ]
pages_indentical()
[ ok ]
Write to page
different value
[Ok, using stale
PTE]
replace_page()
Later, CPU1, CPU2 and CPU3 would flush the TLB, but that is too late.
CPU0 already wrote on the page, but KSM ignored this write, and it got
lost"
In above scenario, MADV_FREE is fixed by changing TLB batching API
including [set|clear]_tlb_flush_pending. Remained thing is soft-dirty
part.
This patch changes soft-dirty uses TLB batching API instead of
flush_tlb_mm and KSM checks pending TLB flush by using
mm_tlb_flush_pending so that it will flush TLB to avoid data lost if
there are other parallel threads pending TLB flush.
[1] http://lkml.kernel.org/r/BD3A0EBE-ECF4-41D4-87FA-C755EA9AB6BD@gmail.com
Link: http://lkml.kernel.org/r/20170802000818.4760-8-namit@vmware.com
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Nadav Amit <namit@vmware.com>
Reported-by: Nadav Amit <namit@vmware.com>
Tested-by: Nadav Amit <namit@vmware.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As Tetsuo points out:
"Commit 385386cff4 ("mm: vmstat: move slab statistics from zone to
node counters") broke "Slab:" field of /proc/meminfo . It shows nearly
0kB"
In addition to /proc/meminfo, this problem also affects the slab
counters OOM/allocation failure info dumps, can cause early -ENOMEM from
overcommit protection, and miscalculate image size requirements during
suspend-to-disk.
This is because the patch in question switched the slab counters from
the zone level to the node level, but forgot to update the global
accessor functions to read the aggregate node data instead of the
aggregate zone data.
Use global_node_page_state() to access the global slab counters.
Fixes: 385386cff4 ("mm: vmstat: move slab statistics from zone to node counters")
Link: http://lkml.kernel.org/r/20170801134256.5400-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Stefan Agner <stefan@agner.ch>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the call to TEST_STATEID returns NFS4ERR_OLD_STATEID, then it just
means we raced with other calls to OPEN.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The client was freeing the nfs4_ff_layout_ds, but not the contained
nfs4_ff_ds_version array.
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Trond Myklebust