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>
Anchor an nfs4_slot_table in the nfs_client for use with NFSv4.0
transport blocking. It is initialized only for NFSv4.0 nfs_client's.
Introduce appropriate minor version ops to handle nfs_client
initialization and shutdown requirements that differ for each minor
version.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Refactor nfs4_call_sync_sequence() so it is used for NFSv4.0 now.
The RPC callouts will house transport blocking logic similar to
NFSv4.1 sessions.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: Both the NFSv4.0 and NFSv4.1 version of
nfs4_setup_sequence() are used only in fs/nfs/nfs4proc.c. No need
to keep global header declarations for either version.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
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>
* labeled-nfs:
NFS: Apply v4.1 capabilities to v4.2
NFS: Add in v4.2 callback operation
NFS: Make callbacks minor version generic
Kconfig: Add Kconfig entry for Labeled NFS V4 client
NFS: Extend NFS xattr handlers to accept the security namespace
NFS: Client implementation of Labeled-NFS
NFS: Add label lifecycle management
NFS:Add labels to client function prototypes
NFSv4: Extend fattr bitmaps to support all 3 words
NFSv4: Introduce new label structure
NFSv4: Add label recommended attribute and NFSv4 flags
NFSv4.2: Added NFS v4.2 support to the NFS client
SELinux: Add new labeling type native labels
LSM: Add flags field to security_sb_set_mnt_opts for in kernel mount data.
Security: Add Hook to test if the particular xattr is part of a MAC model.
Security: Add hook to calculate context based on a negative dentry.
NFS: Add NFSv4.2 protocol constants
Conflicts:
fs/nfs/nfs4proc.c
The fattr handling bitmap code only uses the first two fattr words sofar. This
patch adds the 3rd word to being sent but doesn't populate it yet.
Signed-off-by: Miguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: Phua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: Khin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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>
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>
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>
Clean up the setting of the nfs_server->caps, by shoving it all
into nfs4_server_common_setup().
Then add an 'initial capabilities' field into struct nfs4_minor_version_ops.
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 we replay a READ or WRITE call, we should not be changing the
stateid. Currently, we may end up doing so, because the stateid
is only selected at xdr encode time.
This patch ensures that we select the stateid after we get an NFSv4.1
session slot, and that we keep that same stateid across retries.
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>
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>
We shouldn't need to pass the 'cache_reply' parameter if we
initialise the sequence_args/sequence_res in the caller.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Nobody calls nfs4_setup_sequence or nfs41_setup_sequence without
also calling rpc_call_start() on success. This commit therefore
folds the rpc_call_start call into nfs41_setup_sequence().
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>
Ensure that the NFSv4.1 CB_RECALL_SLOT callback updates the slot table
target max slotid safely.
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>
An optional boot parameter is introduced to allow client
administrators to specify a string that the Linux NFS client can
insert into its nfs_client_id4 id string, to make it both more
globally unique, and to ensure that it doesn't change even if the
client's nodename changes.
If this boot parameter is not specified, the client's nodename is
used, as before.
Client installation procedures can create a unique string (typically,
a UUID) which remains unchanged during the lifetime of that client
instance. This works just like creating a UUID for the label of the
system's root and boot volumes.
Signed-off-by: Chuck Lever <chuck.lever@oracle.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>
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>
Some systems have a modprobe.d/nfs.conf file that sets an nfs4 alias
pointing to nfs.ko, rather than nfs4.ko. This can prevent the v4 module
from loading on mount, since the kernel sees that something named "nfs4"
has already been loaded. To work around this, I've renamed the modules
to "nfsv2.ko" "nfsv3.ko" and "nfsv4.ko".
I also had to move the nfs4_fs_type back to nfs.ko to ensure that `mount
-t nfs4` still works.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This patch exports symbols needed by the v4 module. In addition, I also
switch over to using IS_ENABLED() to check if CONFIG_NFS_V4 or
CONFIG_NFS_V4_MODULE are set.
The module (nfs4.ko) will be created in the same directory as nfs.ko and
will be automatically loaded the first time you try to mount over NFS v4.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Somehow I missed this in my previous patch series, but these functions
are only needed by the v4 code and should be moved to a v4-only file. I
wasn't exactly sure where I should put these functions, so I moved them
into nfs4super.c where I could make them static.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
I'm already looking up the nfs subversion in nfs_fs_mount(), so I have
easy access to rpc_ops that used to be difficult to reach. This allows
me to set up a different mount path for NFS v2/3 and NFS v4.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This patch adds in the code to track multiple versions of the NFS
protocol. I created default structures for v2, v3 and v4 so that each
version can continue to work while I convert them into kernel modules.
I also removed the const parameter from the rpc_version array so that I
can change it at runtime.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Fix numerous repeated warnings by making the stub function
void instead of non-void:
fs/nfs/nfs4_fs.h: In function 'nfs4_unregister_sysctl':
fs/nfs/nfs4_fs.h:385:1: warning: no return statement in function returning non-void
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This allows me to move the v4 mounting and unmounting functions out of
the generic client and into a file that is only compiled when CONFIG_NFS_V4
is enabled.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
And split them out of the generic client into their own file.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
I want to initialize all of NFS v4 in a single function that will
eventually be used as the v4 module init function.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The NFS v4 file inode operations are already already in nfs4proc.c, so
this patch just needs to move the directory operations to the same file.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This gives pnfs a chance to do a layout commit inside the v4 code.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This gives NFS v4 a way to set up callbacks and sessions without v2 or
v3 having to do them as well.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFS v4 needs a way to shut down callbacks and sessions, but v2 and v3
don't.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The open recovery code does not need to request a new value for the
mdsthreshold, and so does not allocate a struct nfs4_threshold.
The problem is that encode_getfattr_open() will still request an
mdsthreshold, and so we end up Oopsing in decode_attr_mdsthreshold.
This patch fixes encode_getfattr_open so that it doesn't request an
mdsthreshold when the caller isn't asking for one. It also fixes
decode_attr_mdsthreshold so that it errors if the server returns
an mdsthreshold that we didn't ask for (instead of Oopsing).
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Andy Adamson <andros@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>
The state manager can handle SEQ4_STATUS_CB_PATH_DOWN* flags with a
BIND_CONN_TO_SESSION instead of destroying the session and creating a new one.
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This patch adds the BIND_CONN_TO_SESSION operation which is needed for
upcoming SP4_MACH_CRED work and useful for recovering from broken connections
without destroying the session.
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
nfs4_reset_all_state() refreshes the boot verifier a server sees to
trigger that server to wipe this client's state. This function is
invoked when an NFSv4.1 server reports that it has revoked some or
all of a client's NFSv4 state.
To facilitate server trunking discovery, we will eventually want to
move the cl_boot_time field to a more global structure. The Uniform
Client String model (and specifically, server trunking detection)
requires that all servers see the same boot verifier until the client
actually does reboot, and not a fresh verifier every time the client
unmounts and remounts the server.
Without the cl_boot_time field, however, nfs4_reset_all_state() will
have to find some other way to force the server to purge the client's
NFSv4 state.
Because these verifiers are opaque (ie, the server doesn't know or
care that they happen to be timestamps), we can force the server
to wipe NFSv4 state by updating the boot verifier as we do now, then
immediately afterwards establish a fresh client ID using the old boot
verifier again.
Hopefully there are no extra paranoid server implementations that keep
track of the client's boot verifiers and prevent clients from reusing
a previous one.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: When naming fields and data types, follow established
conventions to facilitate accurate grep/cscope searches.
Additionally, for consistency, move the scope field into the NFSv4-
specific part of the nfs_client, and free that memory in the logic
that shuts down NFSv4 nfs_clients.
Introduced by commit 99fe60d0 "nfs41: exchange_id operation", April
1 2009.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This function is really getting the root filehandle and not the root
dentry of the filesystem. I also removed the rpc_ops lookup from
nfs4_get_rootfh() under the assumption that if we reach this function
then we already know we are using NFS v4.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This simplifies the code for v2 and v3 and gives v4 a chance to decide
on referrals without needing to modify the generic client.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
I create a new proc_lookup_mountpoint() to use when submounting an NFS
v4 share. This function returns an rpc_clnt to use for performing an
fs_locations() call on a referral's mountpoint.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Whenever lookup sees wrongsec do a secinfo and retry the lookup to find
attributes of the file or directory, such as "is this a referral
mountpoint?". This also allows me to remove handling -NFS4ERR_WRONSEC
as part of getattr xdr decoding.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The NFSv4 spec is ambiguous about whether or not it is permissible
to reuse open owner names, so play it safe. This patch adds a timestamp
to the state_owner structure, and combines that with the IDA based
uniquifier.
Fixes a regression whereby the Linux server returns NFS4ERR_BAD_SEQID.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It is quite possible for the release_lockowner RPC call to race with the
close RPC call, in which case, we cannot dereference lsp->ls_state in
order to find the nfs_server.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Ensure that we select delegation stateids first, then
lock stateids and then open stateids.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If a setattr() fails because of an NFS4ERR_OPENMODE error, it is
probably due to us holding a read delegation. Ensure that the
recovery routines return that delegation in this case.
Reported-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
Otherwise we can end up with sequence id problems if the client reuses
the owner_id before the server has processed the release_lockowner
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Replace the union with the common struct stateid4 as defined in both
RFC3530 and RFC5661. This makes it easier to access the sequence id,
which will again make implementing support for parallel OPEN calls
easier.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It is really a function for selecting the correct stateid to use in a
read or write situation.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Change the name to reflect what we're really doing: testing two
stateids for whether or not they match according the the rules in
RFC3530 and RFC5661.
Move the code from callback_proc.c to nfs4proc.c
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If we know that the delegation stateid is bad or revoked, we need to
remove that delegation as soon as possible, and then mark all the
stateids that relied on that delegation for recovery. We cannot use
the delegation as part of the recovery process.
Also note that NFSv4.1 uses a different error code (NFS4ERR_DELEG_REVOKED)
to indicate that the delegation was revoked.
Finally, ensure that setlk() and setattr() can both recover safely from
a revoked delegation.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
The NFS4CLNT_LAYOUTRECALL bit is a long-term impediment to scalability. It
basically stops all other recalls by a given server once any layout recall
is requested.
If the recall is for a different file, then we don't care.
If the recall applies to the same file, then we're in one of two situations:
Either we are in the case of a replay of an existing request, in which case
the session is supposed to deal with matters, or we are dealing with a
completely different request, in which case we should just try to process
it.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Store a pointer to the rpc_task in struct nfs_seqid so that we can wake up
only that request that is able to grab the lock after we've released it.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We have to ensure that the wake up from the waitqueue and the assignment
of xprt->snd_task are atomic. We can do this by assigning the snd_task
while under the waitqueue spinlock.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Again, We're unlikely to ever need more than 2^31 simultaneous lock
owners, so let's replace the custom allocator.
Now that there are no more users, we can also get rid of the custom
allocator code.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We're unlikely to ever need more than 2^31 simultaneous open owners,
so let's replace the custom allocator with the generic ida allocator.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Servers have a finite amount of memory to store NFSv4 open and lock
owners. Moreover, servers may have a difficult time determining when
they can reap their state owner table, thanks to gray areas in the
NFSv4 protocol specification. Thus clients should be careful to reuse
state owners when possible.
Currently Linux is not too careful. When a user has closed all her
files on one mount point, the state owner's reference count goes to
zero, and it is released. The next OPEN allocates a new one. A
workload that serially opens and closes files can run through a large
number of open owners this way.
When a state owner's reference count goes to zero, slap it onto a free
list for that nfs_server, with an expiry time. Garbage collect before
looking for a state owner. This makes state owners for active users
available for re-use.
Now that there can be unused state owners remaining at umount time,
purge the state owner free list when a server is destroyed. Also be
sure not to reclaim unused state owners during state recovery.
This change has benefits for the client as well. For some workloads,
this approach drops the number of OPEN_CONFIRM calls from the same as
the number of OPEN calls, down to just one. This reduces wire traffic
and thus open(2) latency. Before this patch, untarring a kernel
source tarball shows the OPEN_CONFIRM call counter steadily increasing
through the test. With the patch, the OPEN_CONFIRM count remains at 1
throughout the entire untar.
As long as the expiry time is kept short, I don't think garbage
collection should be terribly expensive, although it does bounce the
clp->cl_lock around a bit.
[ At some point we should rationalize the use of the nfs_server
->destroy method. ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
[Trond: Fixed a garbage collection race and a few efficiency issues]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* 'for-3.2' of git://linux-nfs.org/~bfields/linux: (103 commits)
nfs41: implement DESTROY_CLIENTID operation
nfsd4: typo logical vs bitwise negate for want_mask
nfsd4: allow NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL | NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED
nfsd4: seq->status_flags may be used unitialized
nfsd41: use SEQ4_STATUS_BACKCHANNEL_FAULT when cb_sequence is invalid
nfsd4: implement new 4.1 open reclaim types
nfsd4: remove unneeded CLAIM_DELEGATE_CUR workaround
nfsd4: warn on open failure after create
nfsd4: preallocate open stateid in process_open1()
nfsd4: do idr preallocation with stateid allocation
nfsd4: preallocate nfs4_file in process_open1()
nfsd4: clean up open owners on OPEN failure
nfsd4: simplify process_open1 logic
nfsd4: make is_open_owner boolean
nfsd4: centralize renew_client() calls
nfsd4: typo logical vs bitwise negate
nfs: fix bug about IPv6 address scope checking
nfsd4: more robust ignoring of WANT bits in OPEN
nfsd4: move name-length checks to xdr
nfsd4: move access/deny validity checks to xdr code
...
The NFSv4 spec does not specify that the server must repeat that error,
so in order to avoid having the delegations revoked, we should handle
it immediately.
Also note that NFS4ERR_CB_PATH_DOWN does in fact renew the lease...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
RFC3530 states that if the client holds a delegation, then it is obliged
to continue to send RENEW calls once every lease period in order to allow
the server to return NFS4ERR_CB_PATH_DOWN if the callback path is
unreachable.
This is not required for NFSv4.1, since the server can at any time set
the SEQ4_STATUS_CB_PATH_DOWN_SESSION in any SEQUENCE operation.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Weston Andros Adamson