The current open/lock state recovery unfortunately does not handle errors
such as NFS4ERR_CONN_NOT_BOUND_TO_SESSION correctly. Instead of looping,
just proceeds as if the state manager is finished recovering.
This patch ensures that we loop back, handle higher priority errors
and complete the open/lock state recovery.
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If a NFSv4.x server returns NFS4ERR_STALE_CLIENTID in response to a
CREATE_SESSION or SETCLIENTID_CONFIRM in order to tell us that it rebooted
a second time, then the client will currently take this to mean that it must
declare all locks to be stale, and hence ineligible for reboot recovery.
RFC3530 and RFC5661 both suggest that the client should instead rely on the
server to respond to inelegible open share, lock and delegation reclaim
requests with NFS4ERR_NO_GRACE in this situation.
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Commit c9fdeb28 removed a 'continue' after checking if the lease needs
to be renewed. However, if client hasn't moved, the code falls down to
starting reboot recovery erroneously (ie., sends open reclaim and gets
back stale_clientid error) before recovering from getting stale_clientid
on the renew operation.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Fixes: c9fdeb280b (NFS: Add basic migration support to state manager thread)
Cc: stable@vger.kernel.org # 3.13+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Highlights include:
- Stable fix for a bug in nfs3_list_one_acl()
- Speed up NFS path walks by supporting LOOKUP_RCU
- More read/write code cleanups
- pNFS fixes for layout return on close
- Fixes for the RCU handling in the rpcsec_gss code
- More NFS/RDMA fixes
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=KE07
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-3.17-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
- stable fix for a bug in nfs3_list_one_acl()
- speed up NFS path walks by supporting LOOKUP_RCU
- more read/write code cleanups
- pNFS fixes for layout return on close
- fixes for the RCU handling in the rpcsec_gss code
- more NFS/RDMA fixes"
* tag 'nfs-for-3.17-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (79 commits)
nfs: reject changes to resvport and sharecache during remount
NFS: Avoid infinite loop when RELEASE_LOCKOWNER getting expired error
SUNRPC: remove all refcounting of groupinfo from rpcauth_lookupcred
NFS: fix two problems in lookup_revalidate in RCU-walk
NFS: allow lockless access to access_cache
NFS: teach nfs_lookup_verify_inode to handle LOOKUP_RCU
NFS: teach nfs_neg_need_reval to understand LOOKUP_RCU
NFS: support RCU_WALK in nfs_permission()
sunrpc/auth: allow lockless (rcu) lookup of credential cache.
NFS: prepare for RCU-walk support but pushing tests later in code.
NFS: nfs4_lookup_revalidate: only evaluate parent if it will be used.
NFS: add checks for returned value of try_module_get()
nfs: clear_request_commit while holding i_lock
pnfs: add pnfs_put_lseg_async
pnfs: find swapped pages on pnfs commit lists too
nfs: fix comment and add warn_on for PG_INODE_REF
nfs: check wait_on_bit_lock err in page_group_lock
sunrpc: remove "ec" argument from encrypt_v2 operation
sunrpc: clean up sparse endianness warnings in gss_krb5_wrap.c
sunrpc: clean up sparse endianness warnings in gss_krb5_seal.c
...
The current "wait_on_bit" interface requires an 'action'
function to be provided which does the actual waiting.
There are over 20 such functions, many of them identical.
Most cases can be satisfied by one of just two functions, one
which uses io_schedule() and one which just uses schedule().
So:
Rename wait_on_bit and wait_on_bit_lock to
wait_on_bit_action and wait_on_bit_lock_action
to make it explicit that they need an action function.
Introduce new wait_on_bit{,_lock} and wait_on_bit{,_lock}_io
which are *not* given an action function but implicitly use
a standard one.
The decision to error-out if a signal is pending is now made
based on the 'mode' argument rather than being encoded in the action
function.
All instances of the old wait_on_bit and wait_on_bit_lock which
can use the new version have been changed accordingly and their
action functions have been discarded.
wait_on_bit{_lock} does not return any specific error code in the
event of a signal so the caller must check for non-zero and
interpolate their own error code as appropriate.
The wait_on_bit() call in __fscache_wait_on_invalidate() was
ambiguous as it specified TASK_UNINTERRUPTIBLE but used
fscache_wait_bit_interruptible as an action function.
David Howells confirms this should be uniformly
"uninterruptible"
The main remaining user of wait_on_bit{,_lock}_action is NFS
which needs to use a freezer-aware schedule() call.
A comment in fs/gfs2/glock.c notes that having multiple 'action'
functions is useful as they display differently in the 'wchan'
field of 'ps'. (and /proc/$PID/wchan).
As the new bit_wait{,_io} functions are tagged "__sched", they
will not show up at all, but something higher in the stack. So
the distinction will still be visible, only with different
function names (gds2_glock_wait versus gfs2_glock_dq_wait in the
gfs2/glock.c case).
Since first version of this patch (against 3.15) two new action
functions appeared, on in NFS and one in CIFS. CIFS also now
uses an action function that makes the same freezer aware
schedule call as NFS.
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: David Howells <dhowells@redhat.com> (fscache, keys)
Acked-by: Steven Whitehouse <swhiteho@redhat.com> (gfs2)
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steve French <sfrench@samba.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140707051603.28027.72349.stgit@notabene.brown
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We got a report of the following warning in Fedora:
BUG: sleeping function called from invalid context at mm/slub.c:969
in_atomic(): 1, irqs_disabled(): 0, pid: 533, name: bash
3 locks held by bash/533:
#0: (&sp->so_delegreturn_mutex){+.+...}, at: [<ffffffffa033da62>] nfs4_proc_lock+0x262/0x910 [nfsv4]
#1: (&nfsi->rwsem){.+.+.+}, at: [<ffffffffa033da6a>] nfs4_proc_lock+0x26a/0x910 [nfsv4]
#2: (&sb->s_type->i_lock_key#23){+.+...}, at: [<ffffffff812998dc>] flock_lock_file_wait+0x8c/0x3a0
CPU: 0 PID: 533 Comm: bash Not tainted 3.15.0-0.rc1.git1.1.fc21.x86_64 #1
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
0000000000000000 00000000d664ff3c ffff880078b69a70 ffffffff817e82e0
0000000000000000 ffff880078b69a98 ffffffff810cf1a4 0000000000000050
0000000000000050 ffff88007cc01a00 ffff880078b69ad8 ffffffff8121449e
Call Trace:
[<ffffffff817e82e0>] dump_stack+0x4d/0x66
[<ffffffff810cf1a4>] __might_sleep+0x184/0x240
[<ffffffff8121449e>] kmem_cache_alloc_trace+0x4e/0x330
[<ffffffffa0331124>] ? nfs4_release_lockowner+0x74/0x110 [nfsv4]
[<ffffffffa0331124>] nfs4_release_lockowner+0x74/0x110 [nfsv4]
[<ffffffffa0352340>] nfs4_put_lock_state+0x90/0xb0 [nfsv4]
[<ffffffffa0352375>] nfs4_fl_release_lock+0x15/0x20 [nfsv4]
[<ffffffff81297515>] locks_free_lock+0x45/0x90
[<ffffffff8129996c>] flock_lock_file_wait+0x11c/0x3a0
[<ffffffffa033da6a>] ? nfs4_proc_lock+0x26a/0x910 [nfsv4]
[<ffffffffa033301e>] do_vfs_lock+0x1e/0x30 [nfsv4]
[<ffffffffa033da79>] nfs4_proc_lock+0x279/0x910 [nfsv4]
[<ffffffff810dbb26>] ? local_clock+0x16/0x30
[<ffffffff810f5a3f>] ? lock_release_holdtime.part.28+0xf/0x200
[<ffffffffa02f820c>] do_unlk+0x8c/0xc0 [nfs]
[<ffffffffa02f85c5>] nfs_flock+0xa5/0xf0 [nfs]
[<ffffffff8129a6f6>] locks_remove_file+0xb6/0x1e0
[<ffffffff812159d8>] ? kfree+0xd8/0x2d0
[<ffffffff8123bc63>] __fput+0xd3/0x210
[<ffffffff8123bdee>] ____fput+0xe/0x10
[<ffffffff810bfb6d>] task_work_run+0xcd/0xf0
[<ffffffff81019cd1>] do_notify_resume+0x61/0x90
[<ffffffff817fbea2>] int_signal+0x12/0x17
The problem is that NFSv4 is trying to do an allocation from
fl_release_private (in order to send a RELEASE_LOCKOWNER call). That
function can be called while holding the inode->i_lock, and it's
currently set up to do __GFP_WAIT allocations. v4.1 code has a
similar problem.
This patch adds a work_struct to the nfs4_lock_state and has the code
queue the free_lock_state operation to nfsiod.
Reported-by: Josh Stone <jistone@redhat.com>
Signed-off-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Do the following set of ops with a file on a NFSv4 mount:
exec 3>>/file/on/nfsv4
flock -x 3
exec 3>&-
You'll see the LOCK request go across the wire, but no LOCKU when the
file is closed.
What happens is that the fd is passed across a fork, and the final close
is done in a different process than the opener. That makes
__nfs4_find_lock_state miss finding the correct lock state because it
uses the fl_pid as a search key. A new one is created, and the locking
code treats it as a delegation stateid (because NFS_LOCK_INITIALIZED
isn't set).
The root cause of this breakage seems to be commit 77041ed9b4
(NFSv4: Ensure the lockowners are labelled using the fl_owner and/or
fl_pid).
That changed it so that flock lockowners are allocated based on the
fl_pid. I think this is incorrect. flock locks should be "owned" by the
struct file, and that is already accounted for in the fl_owner field of
the lock request when it comes through nfs_flock.
This patch basically reverts the above commit and with it, a LOCKU is
sent in the above reproducer.
Signed-off-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Highlights include:
- Massive cleanup of the NFS read/write code by Anna and Dros
- Support multiple NFS read/write requests per page in order to deal with
non-page aligned pNFS striping. Also cleans up the r/wsize < page size
code nicely.
- stable fix for ensuring inode is declared uptodate only after all the
attributes have been checked.
- stable fix for a kernel Oops when remounting
- NFS over RDMA client fixes
- move the pNFS files layout driver into its own subdirectory
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=OyXR
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-3.16-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
- massive cleanup of the NFS read/write code by Anna and Dros
- support multiple NFS read/write requests per page in order to deal
with non-page aligned pNFS striping. Also cleans up the r/wsize <
page size code nicely.
- stable fix for ensuring inode is declared uptodate only after all
the attributes have been checked.
- stable fix for a kernel Oops when remounting
- NFS over RDMA client fixes
- move the pNFS files layout driver into its own subdirectory"
* tag 'nfs-for-3.16-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (79 commits)
NFS: populate ->net in mount data when remounting
pnfs: fix lockup caused by pnfs_generic_pg_test
NFSv4.1: Fix typo in dprintk
NFSv4.1: Comment is now wrong and redundant to code
NFS: Use raw_write_seqcount_begin/end int nfs4_reclaim_open_state
xprtrdma: Disconnect on registration failure
xprtrdma: Remove BUG_ON() call sites
xprtrdma: Avoid deadlock when credit window is reset
SUNRPC: Move congestion window constants to header file
xprtrdma: Reset connection timeout after successful reconnect
xprtrdma: Use macros for reconnection timeout constants
xprtrdma: Allocate missing pagelist
xprtrdma: Remove Tavor MTU setting
xprtrdma: Ensure ia->ri_id->qp is not NULL when reconnecting
xprtrdma: Reduce the number of hardway buffer allocations
xprtrdma: Limit work done by completion handler
xprtrmda: Reduce calls to ib_poll_cq() in completion handlers
xprtrmda: Reduce lock contention in completion handlers
xprtrdma: Split the completion queue
xprtrdma: Make rpcrdma_ep_destroy() return void
...
The addition of lockdep code to write_seqcount_begin/end has lead to
a bunch of false positive claims of ABBA deadlocks with the so_lock
spinlock. Audits show that this simply cannot happen because the
read side code does not spin while holding so_lock.
Cc: <stable@vger.kernel.org> # 3.13.x
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
In commit 5521abfdcf (NFSv4: Resend the READ/WRITE RPC call
if a stateid change causes an error), we overloaded the return value of
nfs4_select_rw_stateid() to cause it to return -EWOULDBLOCK if an RPC
call is outstanding that would cause the NFSv4 lock or open stateid
to change.
That is all redundant when we actually copy the stateid used in the
read/write RPC call that failed, and check that against the current
stateid. It is doubly so, when we consider that in the NFSv4.1 case,
we also set the stateid's seqid to the special value '0', which means
'match the current valid stateid'.
Reported-by: Andy Adamson <andros@netapp.com>
Link: http://lkml.kernel.org/r/1393954269-3974-1-git-send-email-andros@netapp.com
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
RFC3530 and RFC5661 both prescribe that the 'opaque' field of the
open stateid returned by new OPEN/OPEN_DOWNGRADE/CLOSE calls for
the same file and open owner should match.
If this is not the case, assume that the open state has been lost,
and that we need to recover it.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
- Stable fix for data corruption when retransmitting O_DIRECT writes
- Stable fix for a deep recursion/stack overflow bug in rpc_release_client
- Stable fix for infinite looping when mounting a NFSv4.x volume
- Fix a typo in the nfs mount option parser
- Allow pNFS layouts to be compiled into the kernel when NFSv4.1 is
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.15 (GNU/Linux)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=uOIM
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-3.13-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes:
- Stable fix for data corruption when retransmitting O_DIRECT writes
- Stable fix for a deep recursion/stack overflow bug in rpc_release_client
- Stable fix for infinite looping when mounting a NFSv4.x volume
- Fix a typo in the nfs mount option parser
- Allow pNFS layouts to be compiled into the kernel when NFSv4.1 is
* tag 'nfs-for-3.13-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
nfs: fix pnfs Kconfig defaults
NFS: correctly report misuse of "migration" mount option.
nfs: don't retry detect_trunking with RPC_AUTH_UNIX more than once
SUNRPC: Avoid deep recursion in rpc_release_client
SUNRPC: Fix a data corruption issue when retransmitting RPC calls
Use this new function to make code more comprehensible, since we are
reinitialzing the completion, not initializing.
[akpm@linux-foundation.org: linux-next resyncs]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, when we try to mount and get back NFS4ERR_CLID_IN_USE or
NFS4ERR_WRONGSEC, we create a new rpc_clnt and then try the call again.
There is no guarantee that doing so will work however, so we can end up
retrying the call in an infinite loop.
Worse yet, we create the new client using rpc_clone_client_set_auth,
which creates the new client as a child of the old one. Thus, we can end
up with a *very* long lineage of rpc_clnts. When we go to put all of the
references to them, we can end up with a long call chain that can smash
the stack as each rpc_free_client() call can recurse back into itself.
This patch fixes this by simply ensuring that the SETCLIENTID call will
only be retried in this situation if the last attempt did not use
RPC_AUTH_UNIX.
Note too that with this change, we don't need the (i > 2) check in the
-EACCES case since we now have a more reliable test as to whether we
should reattempt.
Cc: stable@vger.kernel.org # v3.10+
Cc: Chuck Lever <chuck.lever@oracle.com>
Tested-by/Acked-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
commit 6686390bab (NFS: remove incorrect "Lock reclaim failed!"
warning.) added a test for a delegation before checking to see if any
reclaimed locks failed. The test however is backward and is only doing
that check when a delegation is held instead of when one isn't.
Cc: NeilBrown <neilb@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Fixes: 6686390bab: NFS: remove incorrect "Lock reclaim failed!" warning.
Cc: stable@vger.kernel.org # 3.12
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In nfs4_wait_clnt_recover(), hold a reference to the clp being
waited on. The state manager can reduce clp->cl_count to 1, in
which case the nfs_put_client() in nfs4_run_state_manager() can
free *clp before wait_on_bit() returns and allows
nfs4_wait_clnt_recover() to run again.
The behavior at that point is non-deterministic. If the waited-on
bit still happens to be zero, wait_on_bit() will wake the waiter as
expected. If the bit is set again (say, if the memory was poisoned
when freed) wait_on_bit() can leave the waiter asleep.
This is a narrow fix which ensures the safety of accessing *clp in
nfs4_wait_clnt_recover(), but does not address the continued use
of a possibly freed *clp after nfs4_wait_clnt_recover() returns
(see nfs_end_delegation_return(), for example).
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
With the advent of NFSv4 sessions in NFSv4.1 and following, a "lease
moved" condition is reported differently than it is in NFSv4.0.
NFSv4 minor version 0 servers return an error status code,
NFS4ERR_LEASE_MOVED, to signal that a lease has moved. This error
causes the whole compound operation to fail. Normal compounds
against this server continue to fail until the client performs
migration recovery on the migrated share.
Minor version 1 and later servers assert a bit flag in the reply to
a compound's SEQUENCE operation to signal LEASE_MOVED. This is not
a fatal condition: operations against this server continue normally.
The server asserts this flag until the client performs migration
recovery on the migrated share.
Note that servers MUST NOT return NFS4ERR_LEASE_MOVED to NFSv4
clients not using NFSv4.0.
After the server asserts any of the sr_status_flags in the SEQUENCE
operation in a typical compound, our client initiates standard lease
recovery. For NFSv4.1+, a stand-alone SEQUENCE operation is
performed to discover what recovery is needed.
If SEQ4_STATUS_LEASE_MOVED is asserted in this stand-alone SEQUENCE
operation, our client attempts to discover which FSIDs have been
migrated, and then performs migration recovery on each.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
A migration on the FSID in play for the current NFS operation
is reported via the error status code NFS4ERR_MOVED.
"Lease moved" means that a migration has occurred on some other
FSID than the one for the current operation. It's a signal that
the client should take action immediately to handle a migration
that it may not have noticed otherwise. This is so that the
client's lease does not expire unnoticed on the destination server.
In NFSv4.0, a moved lease is reported with the NFS4ERR_LEASE_MOVED
error status code.
To recover from NFS4ERR_LEASE_MOVED, check each FSID for that server
to see if it is still present. Invoke nfs4_try_migration() if the
FSID is no longer present on the server.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Migration recovery and state recovery must be serialized, so handle
both in the state manager thread.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
As of commit 5d422301f9 we no longer zero the
state.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When an NFSv4 client loses contact with the server it can lose any
locks that it holds.
Currently when it reconnects to the server it simply tries to reclaim
those locks. This might succeed even though some other client has
held and released a lock in the mean time. So the first client might
think the file is unchanged, but it isn't. This isn't good.
If, when recovery happens, the locks cannot be claimed because some
other client still holds the lock, then we get a message in the kernel
logs, but the client can still write. So two clients can both think
they have a lock and can both write at the same time. This is equally
not good.
There was a patch a while ago
http://comments.gmane.org/gmane.linux.nfs/41917
which tried to address some of this, but it didn't seem to go
anywhere. That patch would also send a signal to the process. That
might be useful but for now this patch just causes writes to fail.
For NFSv4 (unlike v2/v3) there is a strong link between the lock and
the write request so we can fairly easily fail any IO of the lock is
gone. While some applications might not expect this, it is still
safer than allowing the write to succeed.
Because this is a fairly big change in behaviour a module parameter,
"recover_locks", is introduced which defaults to true (the current
behaviour) but can be set to "false" to tell the client not to try to
recover things that were lost.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When CONFIG_NFS_V4_1 is not enabled, gcc emits this warning:
linux/fs/nfs/nfs4state.c:255:12: warning:
‘nfs4_begin_drain_session’ defined but not used [-Wunused-function]
static int nfs4_begin_drain_session(struct nfs_client *clp)
^
Eventually NFSv4.0 migration recovery will invoke this function, but
that has not yet been merged. Hide nfs4_begin_drain_session()
behind CONFIG_NFS_V4_1 for now.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
I'd like to re-use NFSv4.1's slot table machinery for NFSv4.0
transport blocking. Re-organize some of nfs4session.c so the slot
table code is built even when NFS_V4_1 is disabled.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
After reclaiming state that was lost, the NFS client tries to reclaim
any locks, and then checks that each one has NFS_LOCK_INITIALIZED set
(which means that the server has confirmed the lock).
However if the client holds a delegation, nfs_reclaim_locks() simply aborts
(or more accurately it called nfs_lock_reclaim() and that returns without
doing anything).
This is because when a delegation is held, the server doesn't need to
know about locks.
So if a delegation is held, NFS_LOCK_INITIALIZED is not expected, and
its absence is certainly not an error.
So don't print the warnings if NFS_DELGATED_STATE is set.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Never try to use a non-UID 0 user credential for lease management,
as that credential can change out from under us. The server will
block NFSv4 lease recovery with NFS4ERR_CLID_INUSE.
Since the mechanism to acquire a credential for lease management
is now the same for all minor versions, replace the minor version-
specific callout with a single function.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Commit 05f4c350 "NFS: Discover NFSv4 server trunking when mounting"
Fri Sep 14 17:24:32 2012 introduced Uniform Client String support,
which forces our NFS client to establish a client ID immediately
during a mount operation rather than waiting until a user wants to
open a file.
Normally machine credentials (eg. from a keytab) are used to perform
a mount operation that is protected by Kerberos. Before 05fc350,
SETCLIENTID used a machine credential, or fell back to a regular
user's credential if no keytab is available.
On clients that don't have a keytab, performing SETCLIENTID early
means there's no user credential to fall back on, since no regular
user has kinit'd yet. 05f4c350 seems to have broken the ability
to mount with sec=krb5 on clients that don't have a keytab in
kernels 3.7 - 3.10.
To address this regression, commit 4edaa308 (NFS: Use "krb5i" to
establish NFSv4 state whenever possible), Sat Mar 16 15:56:20 2013,
was merged in 3.10. This commit forces the NFS client to fall back
to AUTH_SYS for lease management operations if no keytab is
available.
Neil Brown noticed that, since root is required to kinit to do a
sec=krb5 mount when a client doesn't have a keytab, we can try to
use root's Kerberos credential before AUTH_SYS.
Now, when determining a principal and flavor to use for lease
management, the NFS client tries in this order:
1. Flavor: AUTH_GSS, krb5i
Principal: service principal (via keytab)
2. Flavor: AUTH_GSS, krb5i
Principal: user principal established for UID 0 (via kinit)
3. Flavor: AUTH_SYS
Principal: UID 0 / GID 0
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: when NFSv4.1 support is compiled out,
nfs4_end_drain_session() becomes a stub. Make the synopsis of the
stub match the synopsis of the real version of the function.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Feature highlights include:
- Add basic client support for NFSv4.2
- Add basic client support for Labeled NFS (selinux for NFSv4.2)
- Fix the use of credentials in NFSv4.1 stateful operations, and
add support for NFSv4.1 state protection.
Bugfix highlights:
- Fix another NFSv4 open state recovery race
- Fix an NFSv4.1 back channel session regression
- Various rpc_pipefs races
- Fix another issue with NFSv3 auth negotiation
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.13 (GNU/Linux)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=wGjn
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-3.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Feature highlights include:
- Add basic client support for NFSv4.2
- Add basic client support for Labeled NFS (selinux for NFSv4.2)
- Fix the use of credentials in NFSv4.1 stateful operations, and add
support for NFSv4.1 state protection.
Bugfix highlights:
- Fix another NFSv4 open state recovery race
- Fix an NFSv4.1 back channel session regression
- Various rpc_pipefs races
- Fix another issue with NFSv3 auth negotiation
Please note that Labeled NFS does require some additional support from
the security subsystem. The relevant changesets have all been
reviewed and acked by James Morris."
* tag 'nfs-for-3.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (54 commits)
NFS: Set NFS_CS_MIGRATION for NFSv4 mounts
NFSv4.1 Refactor nfs4_init_session and nfs4_init_channel_attrs
nfs: have NFSv3 try server-specified auth flavors in turn
nfs: have nfs_mount fake up a auth_flavs list when the server didn't provide it
nfs: move server_authlist into nfs_try_mount_request
nfs: refactor "need_mount" code out of nfs_try_mount
SUNRPC: PipeFS MOUNT notification optimization for dying clients
SUNRPC: split client creation routine into setup and registration
SUNRPC: fix races on PipeFS UMOUNT notifications
SUNRPC: fix races on PipeFS MOUNT notifications
NFSv4.1 use pnfs_device maxcount for the objectlayout gdia_maxcount
NFSv4.1 use pnfs_device maxcount for the blocklayout gdia_maxcount
NFSv4.1 Fix gdia_maxcount calculation to fit in ca_maxresponsesize
NFS: Improve legacy idmapping fallback
NFSv4.1 end back channel session draining
NFS: Apply v4.1 capabilities to v4.2
NFSv4.1: Clean up layout segment comparison helper names
NFSv4.1: layout segment comparison helpers should take 'const' parameters
NFSv4: Move the DNS resolver into the NFSv4 module
rpc_pipefs: only set rpc_dentry_ops if d_op isn't already set
...
Calling kthread_run with a single name parameter causes it to be handled
as a format string. Many callers are passing potentially dynamic string
content, so use "%s" in those cases to avoid any potential accidents.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Having a global lock that protects all of this code is a clear
scalability problem. Instead of doing that, move most of the code to be
protected by the i_lock instead. The exceptions are the global lists
that the ->fl_link sits on, and the ->fl_block list.
->fl_link is what connects these structures to the
global lists, so we must ensure that we hold those locks when iterating
over or updating these lists.
Furthermore, sound deadlock detection requires that we hold the
blocked_list state steady while checking for loops. We also must ensure
that the search and update to the list are atomic.
For the checking and insertion side of the blocked_list, push the
acquisition of the global lock into __posix_lock_file and ensure that
checking and update of the blocked_list is done without dropping the
lock in between.
On the removal side, when waking up blocked lock waiters, take the
global lock before walking the blocked list and dequeue the waiters from
the global list prior to removal from the fl_block list.
With this, deadlock detection should be race free while we minimize
excessive file_lock_lock thrashing.
Finally, in order to avoid a lock inversion problem when handling
/proc/locks output we must ensure that manipulations of the fl_block
list are also protected by the file_lock_lock.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We need to ensure that we clear NFS4_SLOT_TBL_DRAINING on the back
channel when we're done recovering the session.
Regression introduced by commit 774d5f14e (NFSv4.1 Fix a pNFS session
draining deadlock)
Signed-off-by: Andy Adamson <andros@netapp.com>
[Trond: Changed order to start back-channel first. Minor code cleanup]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org [>=3.10]
We want to use the same credential for reclaim_complete as we used
for the exchange_id call.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
On a CB_RECALL the callback service thread flushes the inode using
filemap_flush prior to scheduling the state manager thread to return the
delegation. When pNFS is used and I/O has not yet gone to the data server
servicing the inode, a LAYOUTGET can preceed the I/O. Unlike the async
filemap_flush call, the LAYOUTGET must proceed to completion.
If the state manager starts to recover data while the inode flush is sending
the LAYOUTGET, a deadlock occurs as the callback service thread holds the
single callback session slot until the flushing is done which blocks the state
manager thread, and the state manager thread has set the session draining bit
which puts the inode flush LAYOUTGET RPC to sleep on the forechannel slot
table waitq.
Separate the draining of the back channel from the draining of the fore channel
by moving the NFS4_SESSION_DRAINING bit from session scope into the fore
and back slot tables. Drain the back channel first allowing the LAYOUTGET
call to proceed (and fail) so the callback service thread frees the callback
slot. Then proceed with draining the forechannel.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This ensures that the server doesn't need to keep huge numbers of
lock stateids waiting around for the final CLOSE.
See section 8.2.4 in RFC5661.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* rpcsec_gss-from_cel: (21 commits)
NFS: Retry SETCLIENTID with AUTH_SYS instead of AUTH_NONE
NFSv4: Don't clear the machine cred when client establish returns EACCES
NFSv4: Fix issues in nfs4_discover_server_trunking
NFSv4: Fix the fallback to AUTH_NULL if krb5i is not available
NFS: Use server-recommended security flavor by default (NFSv3)
SUNRPC: Don't recognize RPC_AUTH_MAXFLAVOR
NFS: Use "krb5i" to establish NFSv4 state whenever possible
NFS: Try AUTH_UNIX when PUTROOTFH gets NFS4ERR_WRONGSEC
NFS: Use static list of security flavors during root FH lookup recovery
NFS: Avoid PUTROOTFH when managing leases
NFS: Clean up nfs4_proc_get_rootfh
NFS: Handle missing rpc.gssd when looking up root FH
SUNRPC: Remove EXPORT_SYMBOL_GPL() from GSS mech switch
SUNRPC: Make gss_mech_get() static
SUNRPC: Refactor nfsd4_do_encode_secinfo()
SUNRPC: Consider qop when looking up pseudoflavors
SUNRPC: Load GSS kernel module by OID
SUNRPC: Introduce rpcauth_get_pseudoflavor()
SUNRPC: Define rpcsec_gss_info structure
NFS: Remove unneeded forward declaration
...
Recently I changed the SETCLIENTID code to use AUTH_GSS(krb5i), and
then retry with AUTH_NONE if that didn't work. This was to enable
Kerberos NFS mounts to work without forcing Linux NFS clients to
have a keytab on hand.
Rick Macklem reports that the FreeBSD server accepts AUTH_NONE only
for NULL operations (thus certainly not for SETCLIENTID). Falling
back to AUTH_NONE means our proposed 3.10 NFS client will not
interoperate with FreeBSD servers over NFSv4 unless Kerberos is
fully configured on both ends.
If the Linux client falls back to using AUTH_SYS instead for
SETCLIENTID, all should work fine as long as the NFS server is
configured to allow AUTH_SYS for SETCLIENTID.
This may still prevent access to Kerberos-only FreeBSD servers by
Linux clients with no keytab. Rick is of the opinion that the
security settings the server applies to its pseudo-fs should also
apply to the SETCLIENTID operation.
Linux and Solaris NFS servers do not place that limitation on
SETCLIENTID. The security settings for the server's pseudo-fs are
determined automatically as the union of security flavors allowed on
real exports, as recommended by RFC 3530bis; and the flavors allowed
for SETCLIENTID are all flavors supported by the respective server
implementation.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Fix nfs4_select_rw_stateid() so that it chooses the open stateid
(or an all-zero stateid) if the delegation does not match the selected
read/write mode.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When we send a RENEW or SEQUENCE operation in order to probe if the
lease is still valid, we want it to be able to time out since the
lease we are probing is likely to time out too. Currently, because
we use soft mount semantics for these RPC calls, the return value
is EIO, which causes the state manager to exit with an "unhandled
error" message.
This patch changes the call semantics, so that the RPC layer returns
ETIMEDOUT instead of EIO. We then have the state manager default to
a simple retry instead of exiting.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When we assign a new rpc_client to clp->cl_rpcclient, we need to destroy
the old one.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org [>=3.7]
The expected behaviour is that the client will decide at mount time
whether or not to use a krb5i machine cred, or AUTH_NULL.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Bryan Schumaker <bjschuma@netapp.com>
- Ensure that we exit with ENOENT if the call to ops->get_clid_cred()
fails.
- Handle the case where ops->detect_trunking() exits with an
unexpected error, and return EIO.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently our client uses AUTH_UNIX for state management on Kerberos
NFS mounts in some cases. For example, if the first mount of a
server specifies "sec=sys," the SETCLIENTID operation is performed
with AUTH_UNIX. Subsequent mounts using stronger security flavors
can not change the flavor used for lease establishment. This might
be less security than an administrator was expecting.
Dave Noveck's migration issues draft recommends the use of an
integrity-protecting security flavor for the SETCLIENTID operation.
Let's ignore the mount's sec= setting and use krb5i as the default
security flavor for SETCLIENTID.
If our client can't establish a GSS context (eg. because it doesn't
have a keytab or the server doesn't support Kerberos) we fall back
to using AUTH_NULL. For an operation that requires a
machine credential (which never represents a particular user)
AUTH_NULL is as secure as AUTH_UNIX.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the open_context for the file is not yet fully initialised,
then open recovery cannot succeed, and since nfs4_state_find_open_context
returns an ENOENT, we end up treating the file as being irrecoverable.
What we really want to do, is just defer the recovery until later.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Follow the practice described in section 8.2.2 of RFC5661: When sending a
read/write or setattr stateid, set the seqid field to zero in order to
signal that the NFS server should apply the most recent locking state.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Adds logic to ensure that if the server returns a BAD_STATEID,
or other state related error, then we check if the stateid has
already changed. If it has, then rather than start state recovery,
we should just resend the failed RPC call with the new stateid.
Allow nfs4_select_rw_stateid to notify that the stateid is unstable by
having it return -EWOULDBLOCK if an RPC is underway that might change the
stateid.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the state recovery failed, we want to ensure that the application
doesn't try to use the same file descriptor for more reads or writes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If state recovery fails with an ESTALE or a ENOENT, then we shouldn't
keep retrying. Instead, mark the stateid as being invalid and
fail the I/O with an EIO error.
For other operations such as POSIX and BSD file locking, truncate
etc, fail with an EBADF to indicate that this file descriptor is no
longer valid.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Add a mutex to the struct nfs4_state_owner to ensure that delegation
recall doesn't conflict with byte range lock removal.
Note that we nest the new mutex _outside_ the state manager reclaim
protection (nfsi->rwsem) in order to avoid deadlocks.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This patch adds a seqcount_t lock for use by the state manager to
signal that an open owner has been recovered. This mechanism will be
used by the delegation, open and byte range lock code in order to
figure out if they need to replay requests due to collisions with
lock recovery.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFS4ERR_DELAY is a legal reply when we call DESTROY_SESSION. It
usually means that the server is busy handling an unfinished RPC
request. Just sleep for a second and then retry.
We also need to be able to handle the NFS4ERR_BACK_CHAN_BUSY return
value. If the NFS server has outstanding callbacks, we just want to
similarly sleep & retry.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
If walking the list in nfs4[01]_walk_client_list fails, then the most
likely explanation is that the server dropped the clientid before we
actually managed to confirm it. As long as our nfs_client is the very
last one in the list to be tested, the caller can be assured that this
is the case when the final return value is NFS4ERR_STALE_CLIENTID.
Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org [>=3.7]
Tested-by: Ben Greear <greearb@candelatech.com>
This list was designed to store struct nfs4_client in the client side.
But nfs4_client was obsolete and has been removed from the source code.
So remove the unused list.
Signed-off-by: Yanchuan Nian <ycnian@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, when an RPCSEC_GSS context has expired or is non-existent
and the users (Kerberos) credentials have also expired or are non-existent,
the client receives the -EKEYEXPIRED error and tries to refresh the context
forever. If an application is performing I/O, or other work against the share,
the application hangs, and the user is not prompted to refresh/establish their
credentials. This can result in a denial of service for other users.
Users are expected to manage their Kerberos credential lifetimes to mitigate
this issue.
Move the -EKEYEXPIRED handling into the RPC layer. Try tk_cred_retry number
of times to refresh the gss_context, and then return -EACCES to the application.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, we see a lot of bouncing for the value of highest_used_slotid
due to the fact that slots are getting freed, instead of getting instantly
transmitted to the next waiting task.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It is more important to preserve the task priority behaviour, which ensures
that things like reclaim writes take precedence over background and kupdate
writes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the server requests a lower target_highest_slotid, then ensure
that we ping it with at least one RPC call containing an
appropriate SEQUENCE op. This ensures that the server won't need to
send a recall callback in order to shrink the slot table.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
nfs4_wait_clnt_recover and nfs4_client_recover_expired_lease are both
generic state related functions. As such, they belong in nfs4state.c,
and not nfs4proc.c
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Coalesce nfs4_check_drain_bc_complete and nfs4_check_drain_fc_complete
into a single function that can be called when the slot table is known
to be empty, then change nfs4_callback_free_slot() and nfs4_free_slot()
to use it.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
RFC5661 requires us to make sure that the server knows we've updated
our slot table size by sending at least one SEQUENCE op containing the
new 'highest_slotid' value.
We can do so using the 'CHECK_LEASE' functionality of the state
manager.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The state manager no longer needs any special machinery to stop the
session flow and resize the slot table. It is all done on the fly by
the SEQUENCE op code now.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Instead of an array of slots, use a singly linked list of slots that
can be dynamically appended to or shrunk.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Allow the server to control the size of the session slot table
by adjusting the value of sr_target_max_slots in the reply to the
SEQUENCE operation.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Dynamic slot allocation in NFSv4.1 depends on the client being able to
track the server's target value for the highest slotid in the
slot table. See the reference in Section 2.10.6.1 of RFC5661.
To avoid ordering problems in the case where 2 SEQUENCE replies contain
conflicting updates to this target value, we also introduce a generation
counter, to track whether or not an RPC containing a SEQUENCE operation
was launched before or after the last update.
Also rename the nfs4_slot_table target_max_slots field to
'target_highest_slotid' to avoid confusion with a slot
table size or number of slots.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Move the session pointer into the slot table, then have struct nfs4_slot
point to that slot table.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We can't send a SEQUENCE op unless the session is OK, so it is pointless
to handle the CHECK_LEASE state before we've dealt with SESSION_RESET
and BIND_CONN_TO_SESSION.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Since the addition of NFSv4 server trunking detection the mount context
calls nfs4_proc_exchange_id then schedules the state manager, which also
calls nfs4_proc_exchange_id. Setting the NFS4CLNT_LEASE_CONFIRM bit
makes the state manager skip the unneeded EXCHANGE_ID and continue on
with session creation.
Reported-by: Jorge Mora <mora@netapp.com>
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We should reclaim reboot state when the clientid is stale.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
"Server trunking" is a fancy named for a multi-homed NFS server.
Trunking might occur if a client sends NFS requests for a single
workload to multiple network interfaces on the same server. There
are some implications for NFSv4 state management that make it useful
for a client to know if a single NFSv4 server instance is
multi-homed. (Note this is only a consideration for NFSv4, not for
legacy versions of NFS, which are stateless).
If a client cares about server trunking, no NFSv4 operations can
proceed until that client determines who it is talking to. Thus
server IP trunking discovery must be done when the client first
encounters an unfamiliar server IP address.
The nfs_get_client() function walks the nfs_client_list and matches
on server IP address. The outcome of that walk tells us immediately
if we have an unfamiliar server IP address. It invokes
nfs_init_client() in this case. Thus, nfs4_init_client() is a good
spot to perform trunking discovery.
Discovery requires a client to establish a fresh client ID, so our
client will now send SETCLIENTID or EXCHANGE_ID as the first NFS
operation after a successful ping, rather than waiting for an
application to perform an operation that requires NFSv4 state.
The exact process for detecting trunking is different for NFSv4.0 and
NFSv4.1, so a minorversion-specific init_client callout method is
introduced.
CLID_INUSE recovery is important for the trunking discovery process.
CLID_INUSE is a sign the server recognizes the client's nfs_client_id4
id string, but the client is using the wrong principal this time for
the SETCLIENTID operation. The SETCLIENTID must be retried with a
series of different principals until one works, and then the rest of
trunking discovery can proceed.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the state manager thread is not actually able to fully recover from
some situation, it wakes up waiters, who kick off a new state manager
thread. Quite often the fresh invocation of the state manager is just
as successful.
This results in a livelock as the client dumps thousands of NFS
requests a second on the network in a vain attempt to recover. Not
very friendly.
To mitigate this situation, add a delay in the state manager after
an unhandled error, so that the client sends just a few requests
every second in this case.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We want to be able to pass on the information that the page was not
dirtied under a lock. Instead of adding a flag parameter, do this
by passing a pointer to a 'struct nfs_lock_owner' that may be NULL.
Also reuse this structure in struct nfs_lock_context to carry the
fl_owner_t and pid_t.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
For NFSv4 minor version 0, currently the cl_id_uniquifier allows the
Linux client to generate a unique nfs_client_id4 string whenever a
server replies with NFS4ERR_CLID_INUSE.
This implementation seems to be based on a flawed reading of RFC
3530. NFS4ERR_CLID_INUSE actually means that the client has presented
this nfs_client_id4 string with a different principal at some time in
the past, and that lease is still in use on the server.
For a Linux client this might be rather difficult to achieve: the
authentication flavor is named right in the nfs_client_id4.id
string. If we change flavors, we change strings automatically.
So, practically speaking, NFS4ERR_CLID_INUSE means there is some other
client using our string. There is not much that can be done to
recover automatically. Let's make it a permanent error.
Remove the recovery logic in nfs4_proc_setclientid(), and remove the
cl_id_uniquifier field from the nfs_client data structure. And,
remove the authentication flavor from the nfs_client_id4 string.
Keeping the authentication flavor in the nfs_client_id4.id string
means that we could have a separate lease for each authentication
flavor used by mounts on the client. But we want just one lease for
all the mounts on this client.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Handling a slot recall situation should always takes precedence over
state recovery to allow the server to manage its resources.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Both nfs4_reset_session and nfs41_init_clientid need to clear all the
session related state flags on success.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The results from a call to nfs4_proc_create_session() should always
be fed into nfs4_handle_reclaim_lease_error, so that we can
handle errors such as NFS4ERR_SEQ_MISORDERED correctly.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Let nfs4_schedule_session_recovery() handle the details of choosing
between resetting the session, and other session related recovery.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
