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>
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>
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>
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>
Now that the writes will schedule a commit on their own, we don't
need nfs_write_inode() to schedule one if there are outstanding
writes, and we're being called in non-blocking mode.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If the page cache is being flushed, then we want to ensure that we
do start a commit once the pages are done being flushed.
If we just wait until all I/O is done to that file, we can end up
livelocking until the balance_dirty_pages() mechanism puts its
foot down and forces I/O to stop.
So instead we do more or less the same thing that O_DIRECT does,
and set up a counter to tell us when the flush is done,
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Highlights include:
Stable bugfixes:
- Fix use after free in write error path
- Use GFP_NOIO for two allocations in writeback
- Fix a hang in OPEN related to server reboot
- Check the result of nfs4_pnfs_ds_connect
- Fix an rcu lock leak
Features:
- Removal of the unmaintained and unused OSD pNFS layout
- Cleanup and removal of lots of unnecessary dprintk()s
- Cleanup and removal of some memory failure paths now that
GFP_NOFS is guaranteed to never fail.
- Remove the v3-only data server limitation on pNFS/flexfiles
Bugfixes:
- RPC/RDMA connection handling bugfixes
- Copy offload: fixes to ensure the copied data is COMMITed to disk.
- Readdir: switch back to using the ->iterate VFS interface
- File locking fixes from Ben Coddington
- Various use-after-free and deadlock issues in pNFS
- Write path bugfixes
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Merge tag 'nfs-for-4.12-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Stable bugfixes:
- Fix use after free in write error path
- Use GFP_NOIO for two allocations in writeback
- Fix a hang in OPEN related to server reboot
- Check the result of nfs4_pnfs_ds_connect
- Fix an rcu lock leak
Features:
- Removal of the unmaintained and unused OSD pNFS layout
- Cleanup and removal of lots of unnecessary dprintk()s
- Cleanup and removal of some memory failure paths now that GFP_NOFS
is guaranteed to never fail.
- Remove the v3-only data server limitation on pNFS/flexfiles
Bugfixes:
- RPC/RDMA connection handling bugfixes
- Copy offload: fixes to ensure the copied data is COMMITed to disk.
- Readdir: switch back to using the ->iterate VFS interface
- File locking fixes from Ben Coddington
- Various use-after-free and deadlock issues in pNFS
- Write path bugfixes"
* tag 'nfs-for-4.12-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (89 commits)
pNFS/flexfiles: Always attempt to call layoutstats when flexfiles is enabled
NFSv4.1: Work around a Linux server bug...
NFS append COMMIT after synchronous COPY
NFSv4: Fix exclusive create attributes encoding
NFSv4: Fix an rcu lock leak
nfs: use kmap/kunmap directly
NFS: always treat the invocation of nfs_getattr as cache hit when noac is on
Fix nfs_client refcounting if kmalloc fails in nfs4_proc_exchange_id and nfs4_proc_async_renew
NFSv4.1: RECLAIM_COMPLETE must handle NFS4ERR_CONN_NOT_BOUND_TO_SESSION
pNFS: Fix NULL dereference in pnfs_generic_alloc_ds_commits
pNFS: Fix a typo in pnfs_generic_alloc_ds_commits
pNFS: Fix a deadlock when coalescing writes and returning the layout
pNFS: Don't clear the layout return info if there are segments to return
pNFS: Ensure we commit the layout if it has been invalidated
pNFS: Don't send COMMITs to the DSes if the server invalidated our layout
pNFS/flexfiles: Fix up the ff_layout_write_pagelist failure path
pNFS: Ensure we check layout validity before marking it for return
NFS4.1 handle interrupted slot reuse from ERR_DELAY
NFSv4: check return value of xdr_inline_decode
nfs/filelayout: fix NULL pointer dereference in fl_pnfs_update_layout()
...
Instead of messing with the commit path which has been causing issues,
add a COMMIT op after the COPY and ask for stable copies in the first
space.
It saves a round trip, since after the COPY, the client sends a COMMIT
anyway.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the client receives a fatal server error from nfs_pageio_add_request(),
then we should always truncate the page on which the error occurred.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the server has already returned a fatal write error that the user
has not yet received on this file, then don't write back the other pages.
Instead, act as if they have been sent, and have returned with the same
error.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Allocate struct backing_dev_info separately instead of embedding it
inside the superblock. This unifies handling of bdi among users.
CC: Anna Schumaker <anna.schumaker@netapp.com>
CC: linux-nfs@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Let's try to have it in a cacheline in nfs4_proc_pgio_rpc_prepare().
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When passed GFP flags that allow sleeping (such as
GFP_NOIO), mempool_alloc() will never return NULL, it will
wait until memory is available.
This means that we don't need to handle failure, but that we
do need to ensure one thread doesn't call mempool_alloc()
twice on the one pool without queuing or freeing the first
allocation. If multiple threads did this during times of
high memory pressure, the pool could be exhausted and a
deadlock could result.
pnfs_generic_alloc_ds_commits() attempts to allocate from
the nfs_commit_mempool while already holding an allocation
from that pool. This is not safe. So change
nfs_commitdata_alloc() to take a flag that indicates whether
failure is acceptable.
In pnfs_generic_alloc_ds_commits(), accept failure and
handle it as we currently do. Else where, do not accept
failure, and do not handle it.
Even when failure is acceptable, we want to succeed if
possible. That means both
- using an entry from the pool if there is one
- waiting for direct reclaim is there isn't.
We call mempool_alloc(GFP_NOWAIT) to achieve the first, then
kmem_cache_alloc(GFP_NOIO|__GFP_NORETRY) to achieve the
second. Each of these can fail, but together they do the
best they can without blocking indefinitely.
The objects returned by kmem_cache_alloc() will still be freed
by mempool_free(). This is safe as mempool_alloc() uses
exactly the same function to allocate objects (since the mempool
was created with mempool_create_slab_pool()). The object returned
by mempool_alloc() and kmem_cache_alloc() are indistinguishable
so mempool_free() will handle both identically, either adding to the
pool or calling kmem_cache_free().
Also, don't test for failure when allocating from
nfs_wdata_mempool.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Since commit 4f52b6bb ("NFS: Don't call COMMIT in ->releasepage()"),
no tasks wait on PagePrivate, so the wake introduced in commit 95905446
("NFS: avoid deadlocks with loop-back mounted NFS filesystems.") can
be removed.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Allow line continuations to work properly with KERN_CONT.
Signed-off-by: Joe Perches <joe@perches.com>
[Anna: Add fallback dprintk_cont() for when CONFIG_SUNRPC_DEBUG=n]
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
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>
It now has only one field and is only used in one structure.
So replaced it in that structure by the field it contains.
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
this field is not used in any important way and probably should
have been removed by
Commit: 8003d3c4aa ("nfs4: treat lock owners as opaque values")
which removed the pid argument from nfs4_get_lock_state.
Except in unusual and uninteresting cases, two threads with the same
->tgid will have the same ->files pointer, so keeping them both
for comparison brings no benefit.
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
After using the offset of the swap entry as the key of the swap cache,
the page_index() becomes exactly same as page_file_index(). So the
page_file_index() is removed and the callers are changed to use
page_index() instead.
Link: http://lkml.kernel.org/r/1473270649-27229-2-git-send-email-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Highlights include:
Stable bugfixes:
- nfs: don't create zero-length requests
- Several LAYOUTGET bugfixes
Features:
- Several performance related features
- More aggressive caching when we can rely on close-to-open cache
consistency
- Remove serialisation of O_DIRECT reads and writes
- Optimise several code paths to not flush to disk unnecessarily. However
allow for the idiosyncracies of pNFS for those layout types that need
to issue a LAYOUTCOMMIT before the metadata can be updated on the server.
- SUNRPC updates to the client data receive path
- pNFS/SCSI support RH/Fedora dm-mpath device nodes
- pNFS files/flexfiles can now use unprivileged ports when the generic NFS
mount options allow it.
Bugfixes:
- Don't use RDMA direct data placement together with data integrity or
privacy security flavours
- Remove the RDMA ALLPHYSICAL memory registration mode as it has potential
security holes.
- Several layout recall fixes to improve NFSv4.1 protocol compliance.
- Fix an Oops in the pNFS files and flexfiles connection setup to the DS
- Allow retry of operations that used a returned delegation stateid
- Don't mark the inode as revalidated if a LAYOUTCOMMIT is outstanding
- Fix writeback races in nfs4_copy_range() and nfs42_proc_deallocate()
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Merge tag 'nfs-for-4.8-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Stable bugfixes:
- nfs: don't create zero-length requests
- several LAYOUTGET bugfixes
Features:
- several performance related features
- more aggressive caching when we can rely on close-to-open
cache consistency
- remove serialisation of O_DIRECT reads and writes
- optimise several code paths to not flush to disk unnecessarily.
However allow for the idiosyncracies of pNFS for those layout
types that need to issue a LAYOUTCOMMIT before the metadata can
be updated on the server.
- SUNRPC updates to the client data receive path
- pNFS/SCSI support RH/Fedora dm-mpath device nodes
- pNFS files/flexfiles can now use unprivileged ports when
the generic NFS mount options allow it.
Bugfixes:
- Don't use RDMA direct data placement together with data
integrity or privacy security flavours
- Remove the RDMA ALLPHYSICAL memory registration mode as
it has potential security holes.
- Several layout recall fixes to improve NFSv4.1 protocol
compliance.
- Fix an Oops in the pNFS files and flexfiles connection
setup to the DS
- Allow retry of operations that used a returned delegation
stateid
- Don't mark the inode as revalidated if a LAYOUTCOMMIT is
outstanding
- Fix writeback races in nfs4_copy_range() and
nfs42_proc_deallocate()"
* tag 'nfs-for-4.8-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (104 commits)
pNFS: Actively set attributes as invalid if LAYOUTCOMMIT is outstanding
NFSv4: Clean up lookup of SECINFO_NO_NAME
NFSv4.2: Fix warning "variable ‘stateids’ set but not used"
NFSv4: Fix warning "no previous prototype for ‘nfs4_listxattr’"
SUNRPC: Fix a compiler warning in fs/nfs/clnt.c
pNFS: Remove redundant smp_mb() from pnfs_init_lseg()
pNFS: Cleanup - do layout segment initialisation in one place
pNFS: Remove redundant stateid invalidation
pNFS: Remove redundant pnfs_mark_layout_returned_if_empty()
pNFS: Clear the layout metadata if the server changed the layout stateid
pNFS: Cleanup - don't open code pnfs_mark_layout_stateid_invalid()
NFS: pnfs_mark_matching_lsegs_return() should match the layout sequence id
pNFS: Do not set plh_return_seq for non-callback related layoutreturns
pNFS: Ensure layoutreturn acts as a completion for layout callbacks
pNFS: Fix CB_LAYOUTRECALL stateid verification
pNFS: Always update the layout barrier seqid on LAYOUTGET
pNFS: Always update the layout stateid if NFS_LAYOUT_INVALID_STID is set
pNFS: Clear the layout return tracking on layout reinitialisation
pNFS: LAYOUTRETURN should only update the stateid if the layout is valid
nfs: don't create zero-length requests
...
There are now a number of accounting oddities such as mapped file pages
being accounted for on the node while the total number of file pages are
accounted on the zone. This can be coped with to some extent but it's
confusing so this patch moves the relevant file-based accounted. Due to
throttling logic in the page allocator for reliable OOM detection, it is
still necessary to track dirty and writeback pages on a per-zone basis.
[mgorman@techsingularity.net: fix NR_ZONE_WRITE_PENDING accounting]
Link: http://lkml.kernel.org/r/1468404004-5085-5-git-send-email-mgorman@techsingularity.net
Link: http://lkml.kernel.org/r/1467970510-21195-20-git-send-email-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
NFS doesn't expect requests with wb_bytes set to zero and may make
unexpected decisions about how to handle that request at the page IO layer.
Skip request creation if we won't have any wb_bytes in the request.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Weston Andros Adamson <dros@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
A generic_cred can be used to look up a unx_cred or a gss_cred, so it's
not really safe to use the the generic_cred->acred->ac_flags to store
the NO_CRKEY_TIMEOUT flag. A lookup for a unx_cred triggered while the
KEY_EXPIRE_SOON flag is already set will cause both NO_CRKEY_TIMEOUT and
KEY_EXPIRE_SOON to be set in the ac_flags, leaving the user associated
with the auth_cred to be in a state where they're perpetually doing 4K
NFS_FILE_SYNC writes.
This can be reproduced as follows:
1. Mount two NFS filesystems, one with sec=krb5 and one with sec=sys.
They do not need to be the same export, nor do they even need to be from
the same NFS server. Also, v3 is fine.
$ sudo mount -o v3,sec=krb5 server1:/export /mnt/krb5
$ sudo mount -o v3,sec=sys server2:/export /mnt/sys
2. As the normal user, before accessing the kerberized mount, kinit with
a short lifetime (but not so short that renewing the ticket would leave
you within the 4-minute window again by the time the original ticket
expires), e.g.
$ kinit -l 10m -r 60m
3. Do some I/O to the kerberized mount and verify that the writes are
wsize, UNSTABLE:
$ dd if=/dev/zero of=/mnt/krb5/file bs=1M count=1
4. Wait until you're within 4 minutes of key expiry, then do some more
I/O to the kerberized mount to ensure that RPC_CRED_KEY_EXPIRE_SOON gets
set. Verify that the writes are 4K, FILE_SYNC:
$ dd if=/dev/zero of=/mnt/krb5/file bs=1M count=1
5. Now do some I/O to the sec=sys mount. This will cause
RPC_CRED_NO_CRKEY_TIMEOUT to be set:
$ dd if=/dev/zero of=/mnt/sys/file bs=1M count=1
6. Writes for that user will now be permanently 4K, FILE_SYNC for that
user, regardless of which mount is being written to, until you reboot
the client. Renewing the kerberos ticket (assuming it hasn't already
expired) will have no effect. Grabbing a new kerberos ticket at this
point will have no effect either.
Move the flag to the auth->au_flags field (which is currently unused)
and rename it slightly to reflect that it's no longer associated with
the auth_cred->ac_flags. Add the rpc_auth to the arg list of
rpcauth_cred_key_to_expire and check the au_flags there too. Finally,
add the inode to the arg list of nfs_ctx_key_to_expire so we can
determine the rpc_auth to pass to rpcauth_cred_key_to_expire.
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
We need to ensure that any writes to the destination file are serialised
with the copy, meaning that the writeback has to occur under the inode lock.
Also relax the writeback requirement on the source, and rely on the
stateid checking to tell us if the source rebooted. Add the helper
nfs_filemap_write_and_wait_range() to call pnfs_sync_inode() as
is appropriate for pNFS servers that may need a layoutcommit.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
We should not be interested in looking at the value of the stable field,
since that could take any value.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
NeilBrown