Commit Graph

4639 Commits

Author SHA1 Message Date
Benjamin Coddington
920b4530fb NFS: nfs_rename() handle -ERESTARTSYS dentry left behind
An interrupted rename will leave the old dentry behind if the rename
succeeds.  Fix this by moving the final local work of the rename to
rpc_call_done so that the results of the RENAME can always be handled,
even if the original process has already returned with -ERESTARTSYS.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-02-08 17:02:44 -05:00
Wei Yongjun
68e33bd6bb NFSv4: Fix warning for using 0 as NULL
Fixes the following sparse warning:

fs/nfs/nfs4state.c:862:60: warning: Using plain integer as NULL pointer

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:51 -05:00
Wei Yongjun
2e54b9b1b0 pNFS/flexfiles: Make local symbol layoutreturn_ops static
Fixes the following sparse warning:

fs/nfs/flexfilelayout/flexfilelayout.c:2114:34: warning:
 symbol 'layoutreturn_ops' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:51 -05:00
Anna Schumaker
045c551947 NFS: Return the comparison result directly in nfs41_match_stateid()
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
49ad0145c3 NFS: Clean up nfs41_same_server_scope()
The function is cleaner this way, since we can use the result of
memcmp() directly

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
81b68de493 NFS: No need to set and return status in nfs41_lock_expired()
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
9df1336ca4 NFS: Remove unnecessary goto in nfs4_lookup_root_sec()
Once again, it's easier and cleaner just to return the error directly.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
334f87dd11 NFS: Remove nfs4_recover_expired_lease()
This function doesn't add much, since all it does is access the server's
nfs_client variable.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
d7e9825848 NFS: Remove an extra if in _nfs4_recover_proc_open()
It's simpler just to return the status unconditionally

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
37a8484aef NFS: Return errors directly in _nfs4_opendata_reclaim_to_nfs4_state()
There is no need for a goto just to return an error code without any
cleanup.  Returning the error directly helps to clean up the code.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
820bf85ce2 NFS: Remove nfs4_wait_for_completion_rpc_task()
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
eeea536163 NFS: Clean up _nfs4_is_integrity_protected()
We can cut out the if statement and return the results of the comparison
directly.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
d9b67e1e49 NFS: Fix inconsistent indentation in nfs4proc.c
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
ad05cc0f04 NFS: Make trace_nfs4_setup_sequence() available to NFS v4.0
This tracepoint displays information about the slot that was chosen for
the RPC, in addition to session information.  This could be useful
information for debugging, and we can set the session id hash to 0 to
indicate that there is no session.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
3d35808b1d NFS: Merge the remaining setup_sequence functions
This creates a single place for all the work to happen, using the
presence of a session to determine if extra values need to be set.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
76ee03540f NFS: Check if the slot table is draining from nfs4_setup_sequence()
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
0dcee8bb74 NFS: Handle setup sequence task rescheduling in a single place
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
6994cdd798 NFS: Lock the slot table from a single place during setup sequence
Rather than implementing this twice for NFS v4.0 and v4.1

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
9dd9107f33 NFS: Move slot-already-allocated check into nfs_setup_sequence()
This puts the check in a single place, rather than needing to implement
it twice for v4.0 and v4.1.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
7981c8a659 NFS: Create a single nfs4_setup_sequence() function
The inline ifdef lets us put everything in a single place, rather than
having two (very similar) versions of this function.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
6de7e12f53 NFS: Use nfs4_setup_sequence() everywhere
This does the right thing depending on if we have a session, rather than
needing to handle this manually in multiple places.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
42e1cca7e9 NFS: Change nfs4_setup_sequence() to take an nfs_client structure
I want to have all callers use this function, rather than calling the
NFS v4.0 and v4.1 versions directly.  This includes pNFS, which only has
access to the nfs_client structure in some places.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
172d9de15a NFS: Change nfs4_get_session() to take an nfs_client structure
pNFS only has access to the nfs_client structure, and not the
nfs_server, so we need to make this change so the function can be used
by pNFS as well.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Anna Schumaker
efc6f4aa74 NFS: Move nfs4_get_session() into nfs4_session.h
This puts session related functions together in the same space.  I only
keep one version of this function, since this variable will always be
NULL when using NFS v4.0.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
NeilBrown
6f6e3c09c0 NFS: tidy up nfs_show_mountd_netid
This function is a bit clumsy, incorrectly producing
",mountproto=" if mountd_protocol is 0 and !showdefaults,
and duplicating the code for reporting "auto".

Tidy it up so that it only makes a single seq_printf() call,
and more obviously does the right thing.

Fixes: ee671b016f ("NFS: convert proto= option to use netids rather than a protoname")
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-01-30 13:14:50 -05:00
Joe Perches
ddeaa6379d sunrpc & nfs: Add and use dprintk_cont macros
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>
2017-01-30 13:14:50 -05:00
Trond Myklebust
ee6625a948 pNFS: Fix a reference leak in _pnfs_return_layout
IF NFS_LAYOUT_RETURN_REQUESTED is not set, then we currently exit
without freeing the list of invalidated layout segments, leading
to a reference leak.

Reported-by: Olga Kornievskaia <aglo@umich.edu>
Fixes: 24408f5282 ("pNFS: Fix bugs in _pnfs_return_layout")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-01-26 15:50:41 -05:00
Chuck Lever
406dab8450 nfs: Fix "Don't increment lock sequence ID after NFS4ERR_MOVED"
Lock sequence IDs are bumped in decode_lock by calling
nfs_increment_seqid(). nfs_increment_sequid() does not use the
seqid_mutating_err() function fixed in commit 059aa73482 ("Don't
increment lock sequence ID after NFS4ERR_MOVED").

Fixes: 059aa73482 ("Don't increment lock sequence ID after ...")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Xuan Qi <xuan.qi@oracle.com>
Cc: stable@vger.kernel.org # v3.7+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-01-26 15:25:03 -05:00
Benjamin Coddington
a430607b2e NFSv4.0: always send mode in SETATTR after EXCLUSIVE4
Some nfsv4.0 servers may return a mode for the verifier following an open
with EXCLUSIVE4 createmode, but this does not mean the client should skip
setting the mode in the following SETATTR.  It should only do that for
EXCLUSIVE4_1 or UNGAURDED createmode.

Fixes: 5334c5bdac ("NFS: Send attributes in OPEN request for NFS4_CREATE_EXCLUSIVE4_1")
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Cc: stable@vger.kernel.org # v4.3+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-01-24 12:52:34 -05:00
Trond Myklebust
8ac092519a NFSv4.1: Fix a deadlock in layoutget
We cannot call nfs4_handle_exception() without first ensuring that the
slot has been freed. If not, we end up deadlocking with the process
waiting for recovery to complete, and recovery waiting for the slot
table to drain.

Fixes: 2e80dbe7ac ("NFSv4.1: Close callback races for OPEN, LAYOUTGET...")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-01-23 22:44:12 -05:00
Trond Myklebust
c6180a6237 NFSv4: Fix client recovery when server reboots multiple times
If the server reboots multiple times, the client should rely on the
server to tell it that it cannot reclaim state as per section 9.6.3.4
in RFC7530 and section 8.4.2.1 in RFC5661.
Currently, the client is being to conservative, and is assuming that
if the server reboots while state recovery is in progress, then it must
ignore state that was not recovered before the reboot.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-01-13 13:31:32 -05:00
Trond Myklebust
d3129ef672 NFSv4: update_changeattr should update the attribute timestamp
Otherwise, the attribute cache remains marked as being expired.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-01-12 15:51:19 -05:00
Trond Myklebust
c40d52fe1c NFSv4: Don't call update_changeattr() unless the unlink is successful
If the unlink wasn't successful, then the directory has presumably not
changed.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-01-12 15:51:18 -05:00
Trond Myklebust
c733c49c32 NFSv4: Don't apply change_info4 twice on rename within a directory
If a file is renamed, but stays in the same directory, we will still receive
2 change_info4 structures describing the change to that directory, but we
only want to apply it once.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-01-12 15:51:18 -05:00
Trond Myklebust
2dfc617364 NFSv4: Call update_changeattr() from _nfs4_proc_open only if a file was created
We don't want to invalidate the directory attribute and data cache unless we
know that a file was created, or the change attribute differs from the one
in our cache.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-01-12 15:51:17 -05:00
Benjamin Coddington
4b09ec4b14 nfs: Don't take a reference on fl->fl_file for LOCK operation
I have reports of a crash that look like __fput() was called twice for
a NFSv4.0 file.  It seems possible that the state manager could try to
reclaim a lock and take a reference on the fl->fl_file at the same time the
file is being released if, during the close(), a signal interrupts the wait
for outstanding IO while removing locks which then skips the removal
of that lock.

Since 83bfff23e9 ("nfs4: have do_vfs_lock take an inode pointer") has
removed the need to traverse fl->fl_file->f_inode in nfs4_lock_done(),
taking that reference is no longer necessary.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-01-12 12:51:29 -05:00
Thomas Gleixner
1f3a8e49d8 ktime: Get rid of ktime_equal()
No point in going through loops and hoops instead of just comparing the
values.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
2016-12-25 17:21:23 +01:00
Thomas Gleixner
2456e85535 ktime: Get rid of the union
ktime is a union because the initial implementation stored the time in
scalar nanoseconds on 64 bit machine and in a endianess optimized timespec
variant for 32bit machines. The Y2038 cleanup removed the timespec variant
and switched everything to scalar nanoseconds. The union remained, but
become completely pointless.

Get rid of the union and just keep ktime_t as simple typedef of type s64.

The conversion was done with coccinelle and some manual mopping up.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
2016-12-25 17:21:22 +01:00
Linus Torvalds
7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
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>
2016-12-24 11:46:01 -08:00
Linus Torvalds
bc1ecd626b NFS client updates for Linux 4.10
Highlights include:
 
 - Further attribute cache improvements to make revalidation more fine grained
 - NFSv4 locking improvements
 
 Bugfixes:
 - nfs4_fl_prepare_ds must be careful about reporting success in files layout
 - pNFS/flexfiles: Instead of marking a device inactive, remove it from the cache
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Merge tag 'nfs-for-4.10-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull more NFS client updates from Trond Myklebust:
 "Highlights include:

   - further attribute cache improvements to make revalidation more fine
     grained

   - NFSv4 locking improvements

  Bugfixes:

   - nfs4_fl_prepare_ds must be careful about reporting success in files
     layout

   - pNFS/flexfiles: Instead of marking a device inactive, remove it
     from the cache"

* tag 'nfs-for-4.10-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFSv4: Retry the DELEGRETURN if the embedded GETATTR is rejected with EACCES
  NFS: Retry the CLOSE if the embedded GETATTR is rejected with EACCES
  NFSv4: Place the GETATTR operation before the CLOSE
  NFSv4: Also ask for attributes when downgrading to a READ-only state
  NFS: Don't abuse NFS_INO_REVAL_FORCED in nfs_post_op_update_inode_locked()
  pNFS: Return RW layouts on OPEN_DOWNGRADE
  NFSv4: Add encode/decode of the layoutreturn op in OPEN_DOWNGRADE
  NFS: Don't disconnect open-owner on NFS4ERR_BAD_SEQID
  NFSv4: ensure __nfs4_find_lock_state returns consistent result.
  NFSv4.1: nfs4_fl_prepare_ds must be careful about reporting success.
  pNFS/flexfiles: delete deviceid, don't mark inactive
  NFS: Clean up nfs_attribute_timeout()
  NFS: Remove unused function nfs_revalidate_inode_rcu()
  NFS: Fix and clean up the access cache validity checking
  NFS: Only look at the change attribute cache state in nfs_weak_revalidate()
  NFS: Clean up cache validity checking
  NFS: Don't revalidate the file on close if we hold a delegation
  NFSv4: Don't discard the attributes returned by asynchronous DELEGRETURN
  NFSv4: Update the attribute cache info in update_changeattr
2016-12-21 10:40:30 -08:00
Trond Myklebust
8ac2b42238 NFSv4: Retry the DELEGRETURN if the embedded GETATTR is rejected with EACCES
If our DELEGRETURN RPC call is rejected with an EACCES call, then we should
remove the GETATTR call from the compound RPC and retry.
This could potentially happen when there is a conflict between an
ACL denying attribute reads and our use of SP4_MACH_CRED.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-19 17:30:03 -05:00
Trond Myklebust
f07d4a31cc NFS: Retry the CLOSE if the embedded GETATTR is rejected with EACCES
If our CLOSE RPC call is rejected with an EACCES call, then we should
remove the GETATTR call from the compound RPC and retry.
This could potentially happen when there is a conflict between an
ACL denying attribute reads and our use of SP4_MACH_CRED.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-19 17:30:01 -05:00
Trond Myklebust
d8d849835e NFSv4: Place the GETATTR operation before the CLOSE
In order to benefit from the DENY share lock protection, we should
put the GETATTR operation before the CLOSE. Otherwise, we might race
with a Windows machine that thinks it is now safe to modify the file.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-19 17:30:00 -05:00
Trond Myklebust
9413a1a1bf NFSv4: Also ask for attributes when downgrading to a READ-only state
If we're downgrading from a READ+WRITE mode to a READ-only mode, then
ask for cache consistency attributes so that we avoid the revalidation
in nfs_close_context()

Fixes: 3947b74d0f ("NFSv4: Don't request a GETATTR on open_downgrade.")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-19 17:29:58 -05:00
Trond Myklebust
a5f925bccc NFS: Don't abuse NFS_INO_REVAL_FORCED in nfs_post_op_update_inode_locked()
The NFS_INO_REVAL_FORCED flag now really only has meaning for the
case when we've just been handed a delegation for a file that was already
cached, and we're unsure about that cache.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-19 17:29:56 -05:00
Trond Myklebust
e71708d4df pNFS: Return RW layouts on OPEN_DOWNGRADE
If the client holds no more writeable open state, and does not hold a
write delegation, then send a layoutreturn as part of the OPEN_DOWNGRADE.

We do this only for writes, since some layout drivers may require you to
also hold a read layout if you are doing a R/W workload.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-19 17:29:55 -05:00
Trond Myklebust
b6808145ad NFSv4: Add encode/decode of the layoutreturn op in OPEN_DOWNGRADE
While we do not need to return the RW layout when downgrading from a
read/write open state to read-only, we might want to do so in order
to reduce the burden on the metadataserver so that it does not need
to check for changed data when responding to GETATTR requests.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-19 17:29:52 -05:00
NeilBrown
86cfb04185 NFS: Don't disconnect open-owner on NFS4ERR_BAD_SEQID
When an NFS4ERR_BAD_SEQID is received the open-owner is removed from
the ->state_owners rbtree so that it will no longer be used.

If any stateids attached to this open-owner are still in use, and if a
request using one gets an NFS4ERR_BAD_STATEID reply, this can for bad.

The state is marked as needing recovery and the nfs4_state_manager()
is scheduled to clean up.  nfs4_state_manager() finds states to be
recovered by walking the state_owners rbtree.  As the open-owner is
not in the rbtree, the bad state is not found so nfs4_state_manager()
completes having done nothing.  The request is then retried, with a
predicatable result (indefinite retries).

If the stateid is for a delegation, this open_owner will be used
to open files when the delegation is returned.  For that to work,
a new open-owner needs to be presented to the server.

This patch changes NFS4ERR_BAD_SEQID handling to leave the open-owner
in the rbtree but updates the 'create_time' so it looks like a new
open-owner.  With this the indefinite retries no longer happen.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-19 17:29:51 -05:00
NeilBrown
3f8f25489f NFSv4: ensure __nfs4_find_lock_state returns consistent result.
If a file has both flock locks and OFD locks, then it is possible that
two different nfs4 lock states could apply to file accesses from a
single process.

It is not possible to know, efficiently, which one is "correct".
Presumably the state which represents a lock that covers the region
undergoing IO would be the "correct" one to use, but finding that has
a non-trivial cost and would provide miniscule value.

Currently we just return whichever is first in the list, which could
result in inconsistent behaviour if an application ever put it self in
this position.  As consistent behaviour is preferable (when perfectly
correct behaviour is not available), change the search to return a
consistent result in this circumstance.
Specifically: if there is both a flock and OFD lock state, always return
the flock one.

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-19 17:29:50 -05:00
NeilBrown
cfd278c280 NFSv4.1: nfs4_fl_prepare_ds must be careful about reporting success.
Various places assume that if nfs4_fl_prepare_ds() turns a non-NULL 'ds',
then ds->ds_clp will also be non-NULL.

This is not necessasrily true in the case when the process received a fatal signal
while nfs4_pnfs_ds_connect is waiting in nfs4_wait_ds_connect().
In that case ->ds_clp may not be set, and the devid may not recently have been marked
unavailable.

So add a test for ds_clp == NULL and return NULL in that case.

Fixes: c23266d532 ("NFS4.1 Fix data server connection race")
Signed-off-by: NeilBrown <neilb@suse.com>
Acked-by: Olga Kornievskaia <aglo@umich.edu>
Acked-by: Adamson, Andy <William.Adamson@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-12-19 17:29:48 -05:00