The only time that a lock_context is not immediately available is in
setattr, and now that it has an open_context, it can easily find one
with nfs_get_lock_context.
This removes the need for the on-stack nfs_lockowner.
This change is preparation for correctly support flock stateids.
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the reply to a successful CLOSE call races with an OPEN to the same
file, we can end up scribbling over the stateid that represents the
new open state.
The race looks like:
Client Server
====== ======
CLOSE stateid A on file "foo"
CLOSE stateid A, return stateid C
OPEN file "foo"
OPEN "foo", return stateid B
Receive reply to OPEN
Reset open state for "foo"
Associate stateid B to "foo"
Receive CLOSE for A
Reset open state for "foo"
Replace stateid B with C
The fix is to examine the argument of the CLOSE, and check for a match
with the current stateid "other" field. If the two do not match, then
the above race occurred, and we should just ignore the CLOSE.
Reported-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
According to RFC5661, if any of the SEQUENCE status bits
SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED,
SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED, SEQ4_STATUS_ADMIN_STATE_REVOKED,
or SEQ4_STATUS_RECALLABLE_STATE_REVOKED are set, then we need to use
TEST_STATEID to figure out which stateids have been revoked, so we
can acknowledge the loss of state using FREE_STATEID.
While we already do this for open and lock state, we have not been doing
so for all the delegations.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
As described in RFC5661, section 18.46, some of the status flags exist
in order to tell the client when it needs to acknowledge the existence of
revoked state on the server and/or to recover state.
Those flags will then remain set until the recovery procedure is done.
In order to avoid looping, the client therefore needs to ignore
those particular flags while recovering.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
We want to handle the two cases differently, such that we poll more
aggressively when we don't expect a callback.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Try all multipath addresses for a data server. The first address that
successfully connects and creates a session is the DS mount address.
All subsequent addresses are tested for session trunking and
added as aliases.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Add support for the kernel parameter nfs.callback_nr_threads to set
the number of threads that will be assigned to the callback channel.
Add support for the kernel parameter nfs.nfs.max_session_cb_slots
to set the maximum size of the callback channel slot table.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Highlights include:
- Stable patch from Olga to fix RPCSEC_GSS upcalls when the same user needs
multiple different security services (e.g. krb5i and krb5p).
- Stable patch to fix a regression introduced by the use of SO_REUSEPORT,
and that prevented the use of multiple different NFS versions to the
same server.
- TCP socket reconnection timer fixes.
- Patch from Neil to disable the use of IPv6 temporary addresses.
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Merge tag 'nfs-for-4.8-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
"Highlights include:
- Stable patch from Olga to fix RPCSEC_GSS upcalls when the same user
needs multiple different security services (e.g. krb5i and krb5p).
- Stable patch to fix a regression introduced by the use of
SO_REUSEPORT, and that prevented the use of multiple different NFS
versions to the same server.
- TCP socket reconnection timer fixes.
- Patch from Neil to disable the use of IPv6 temporary addresses"
* tag 'nfs-for-4.8-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFSv4: Cap the transport reconnection timer at 1/2 lease period
NFSv4: Cleanup the setting of the nfs4 lease period
SUNRPC: Limit the reconnect backoff timer to the max RPC message timeout
SUNRPC: Fix reconnection timeouts
NFSv4.2: LAYOUTSTATS may return NFS4ERR_ADMIN/DELEG_REVOKED
SUNRPC: disable the use of IPv6 temporary addresses.
SUNRPC: allow for upcalls for same uid but different gss service
SUNRPC: Fix up socket autodisconnect
SUNRPC: Handle EADDRNOTAVAIL on connection failures
Pull qstr constification updates from Al Viro:
"Fairly self-contained bunch - surprising lot of places passes struct
qstr * as an argument when const struct qstr * would suffice; it
complicates analysis for no good reason.
I'd prefer to feed that separately from the assorted fixes (those are
in #for-linus and with somewhat trickier topology)"
* 'work.const-qstr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
qstr: constify instances in adfs
qstr: constify instances in lustre
qstr: constify instances in f2fs
qstr: constify instances in ext2
qstr: constify instances in vfat
qstr: constify instances in procfs
qstr: constify instances in fuse
qstr constify instances in fs/dcache.c
qstr: constify instances in nfs
qstr: constify instances in ocfs2
qstr: constify instances in autofs4
qstr: constify instances in hfs
qstr: constify instances in hfsplus
qstr: constify instances in logfs
qstr: constify dentry_init_security
Make a helper function nfs4_set_lease_period() and have
nfs41_setup_state_renewal() and nfs4_do_fsinfo() use it.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Fix up nfs4_do_handle_exception() so that it can check if the operation
that received the NFS4ERR_BAD_STATEID was using a defunct delegation.
Apply that to the case of SETATTR, which will currently return EIO
in some cases where this happens.
Reported-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When we're using a delegation to represent our open state, we should
ensure that we use the stateid that was used to create that delegation.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
In order to more easily distinguish what kind of stateid we are dealing
with, introduce a type that can be used to label the stateid structure.
The label will be useful both for debugging, but also when dealing with
operations like SETATTR, READ and WRITE that can take several different
types of stateid as arguments.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
All these functions do is call nfs41_ping_server() without adding
anything. Let's remove them and give nfs41_ping_server() a better name
instead.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
* flexfiles: (53 commits)
pnfs: lookup new lseg at lseg boundary
nfs41: .init_read and .init_write can be called with valid pg_lseg
pnfs: Update documentation on the Layout Drivers
pnfs/flexfiles: Add the FlexFile Layout Driver
nfs: count DIO good bytes correctly with mirroring
nfs41: wait for LAYOUTRETURN before retrying LAYOUTGET
nfs: add a helper to set NFS_ODIRECT_RESCHED_WRITES to direct writes
nfs41: add NFS_LAYOUT_RETRY_LAYOUTGET to layout header flags
nfs/flexfiles: send layoutreturn before freeing lseg
nfs41: introduce NFS_LAYOUT_RETURN_BEFORE_CLOSE
nfs41: allow async version layoutreturn
nfs41: add range to layoutreturn args
pnfs: allow LD to ask to resend read through pnfs
nfs: add nfs_pgio_current_mirror helper
nfs: only reset desc->pg_mirror_idx when mirroring is supported
nfs41: add a debug warning if we destroy an unempty layout
pnfs: fail comparison when bucket verifier not set
nfs: mirroring support for direct io
nfs: add mirroring support to pgio layer
pnfs: pass ds_commit_idx through the commit path
...
Conflicts:
fs/nfs/pnfs.c
fs/nfs/pnfs.h
flexclient needs this as there is no nfs_server to DS connection.
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
Remove the serialisation of OPEN/OPEN_DOWNGRADE and CLOSE calls for the
case of NFSv4.1 and newer.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This patch adds support for using the NFS v4.2 operation ALLOCATE to
preallocate data in a file.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Merge NFSv4.2 client SEEK implementation from Anna
* client-4.2: (55 commits)
NFS: Implement SEEK
NFSD: Implement SEEK
NFSD: Add generic v4.2 infrastructure
svcrdma: advertise the correct max payload
nfsd: introduce nfsd4_callback_ops
nfsd: split nfsd4_callback initialization and use
nfsd: introduce a generic nfsd4_cb
nfsd: remove nfsd4_callback.cb_op
nfsd: do not clear rpc_resp in nfsd4_cb_done_sequence
nfsd: fix nfsd4_cb_recall_done error handling
nfsd4: clarify how grace period ends
nfsd4: stop grace_time update at end of grace period
nfsd: skip subsequent UMH "create" operations after the first one for v4.0 clients
nfsd: set and test NFSD4_CLIENT_STABLE bit to reduce nfsdcltrack upcalls
nfsd: serialize nfsdcltrack upcalls for a particular client
nfsd: pass extra info in env vars to upcalls to allow for early grace period end
nfsd: add a v4_end_grace file to /proc/fs/nfsd
lockd: add a /proc/fs/lockd/nlm_end_grace file
nfsd: reject reclaim request when client has already sent RECLAIM_COMPLETE
nfsd: remove redundant boot_time parm from grace_done client tracking op
...
The SEEK operation is used when an application makes an lseek call with
either the SEEK_HOLE or SEEK_DATA flags set. I fall back on
nfs_file_llseek() if the server does not have SEEK support.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
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>
struct nfs_pgio_data only exists as a member of nfs_pgio_header, but is
passed around everywhere, because there used to be multiple _data structs
per _header. Many of these functions then use the _data to find a pointer
to the _header. This patch cleans this up by merging the nfs_pgio_data
structure into nfs_pgio_header and passing nfs_pgio_header around instead.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Fix nfs4_negotiate_security to create an rpc_clnt used to test each SECINFO
returned pseudoflavor. Check credential creation (and gss_context creation)
which is important for RPC_AUTH_GSS pseudoflavors which can fail for multiple
reasons including mis-configuration.
Don't call nfs4_negotiate in nfs4_submount as it was just called by
nfs4_proc_lookup_mountpoint (nfs4_proc_lookup_common)
Signed-off-by: Andy Adamson <andros@netapp.com>
[Trond: fix corrupt return value from nfs_find_best_sec()]
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
At this point, the only difference between nfs_read_data and
nfs_write_data is the write verifier.
Signed-off-by: Anna Schumaker <Anna.Schumaker@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>
Fix a dynamic session slot leak where a slot is preallocated and I/O is
resent through the MDS.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When CONFIG_NFS_V4_2 is toggled nfsd and lockd will be recompiled,
instead of only the nfs client. This patch moves a small amount of code
into the client directory to avoid unnecessary recompiles.
Signed-off-by: Anna Schumaker <bjschuma@netapp.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>
Introduce a mechanism for probing a server to determine if an FSID
is present or absent.
The on-the-wire compound is different between minor version 0 and 1.
Minor version 0 appends a RENEW operation to identify which client
ID is probing. Minor version 1 has a SEQUENCE operation in the
compound which effectively carries the same information.
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>
The nfs4_proc_fs_locations() function is invoked during referral
processing to perform a GETATTR(fs_locations) on an object's parent
directory in order to discover the target of the referral. It
performs a LOOKUP in the compound, so the client needs to know the
parent's file handle a priori.
Unfortunately this function is not adequate for handling migration
recovery. We need to probe fs_locations information on an FSID, but
there's no parent directory available for many operations that
can return NFS4ERR_MOVED.
Another subtlety: recovering from NFS4ERR_LEASE_MOVED is a process
of walking over a list of known FSIDs that reside on the server, and
probing whether they have migrated. Once the server has detected
that the client has probed all migrated file systems, it stops
returning NFS4ERR_LEASE_MOVED.
A minor version zero server needs to know what client ID is
requesting fs_locations information so it can clear the flag that
forces it to continue returning NFS4ERR_LEASE_MOVED. This flag is
set per client ID and per FSID. However, the client ID is not an
argument of either the PUTFH or GETATTR operations. Later minor
versions have client ID information embedded in the compound's
SEQUENCE operation.
Therefore, by convention, minor version zero clients send a RENEW
operation in the same compound as the GETATTR(fs_locations), since
RENEW's one argument is a clientid4. This allows a minor version
zero server to identify correctly the client that is probing for a
migration.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The differences between minor version 0 and minor version 1
migration will be abstracted by the addition of a set of migration
recovery ops.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Introduce functions that can walk through an array of returned
fs_locations information and connect a transport to one of the
destination servers listed therein.
Note that NFS minor version 1 introduces "fs_locations_info" which
extends the locations array sorting criteria available to clients.
This is not supported yet.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The cl_machine_cred doesn't need to be reference counted here -
a reference is held is for the lifetime of the struct nfs_client.
Also, no need to put_rpccred the rpc_message.rpc_cred.
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFSv4 security auto-negotiation has been broken since
commit 4580a92d44 (NFS:
Use server-recommended security flavor by default (NFSv3))
because nfs4_try_mount() will automatically select AUTH_SYS
if it sees no auth flavours.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
WRITE and COMMIT can use the machine credential.
If WRITE is supported and COMMIT is not, make all (mach cred) writes FILE_SYNC4.
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Add nfs4_state_protect - the function responsible for switching to the machine
credential and the correct rpc client when SP4_MACH_CRED is in use.
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Rename the new 'recover_locks' kernel parameter to 'recover_lost_locks'
and change the default to 'false'. Document why in
Documentation/kernel-parameters.txt
Move the 'recover_lost_locks' kernel parameter to fs/nfs/super.c to
make it easy to backport to kernels prior to 3.6.x, which don't have
a separate NFSv4 module.
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>
NeilBrown