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>
If the client is using NFS v4.1, then we can use SECINFO_NO_NAME to find
the secflavor for the initial mount. If the server doesn't support
SECINFO_NO_NAME then I fall back on the "guess and check" method used
for v4.0 mounts.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
can be skipped if the "eir_server_scope" from the exchange_id proc differs from
previous calls.
Also, in the future server_scope will be useful for determining whether client
trunking is available
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If a server for some reason keeps sending NFS4ERR_DELAY errors, we can end
up looping forever inside nfs4_proc_create_session, and so the usual
mechanisms for detecting if the nfs_client is dead don't work.
Fix this by ensuring that we loop inside the nfs4_state_manager thread
instead.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
A later patch will need to perform a lookup using an
alternate client with a different security flavor.
This patch adds support for doing that on NFS v4.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The filelayout driver sends LAYOUTCOMMIT only when COMMIT goes to
the data server (as opposed to the MDS) and the data server WRITE
is not NFS_FILE_SYNC.
Only whole file layout support means that there is only one IOMODE_RW layout
segment.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Mingyang Guo <guomingyang@nrchpc.ac.cn>
Signed-off-by: Tao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: Zhang Jingwang <zhangjingwang@nrchpc.ac.cn>
Tested-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Attempt a pNFS file layout read by setting up the nfs_read_data struct and
calling nfs_initiate_read with the data server rpc client and the
filelayout rpc call ops.
Error handling is implemented in a subsequent patch.
Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Mingyang Guo <guomingyang@nrchpc.ac.cn>
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Tested-by: Guo Mingyang <guomingyang@nrchpc.ac.cn>
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Introduce a data server set_client and init session following the
nfs4_set_client and nfs4_init_session convention.
Once a new nfs_client is on the nfs_client_list, the nfs_client cl_cons_state
serializes access to creating an nfs_client struct with matching properties.
Use the new nfs_get_client() that initializes new clients.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
There are no more external users of nfs4_state_mark_reclaim_nograce() or
nfs4_state_mark_reclaim_reboot(), so mark them as static.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
nfs4_schedule_state_recovery() should only be used when we need to force
the state manager to check the lease. If we just want to start the
state manager in order to handle a state recovery situation, we should be
using nfs4_schedule_state_manager().
This patch fixes the abuses of nfs4_schedule_state_recovery() by replacing
its use with a set of helper functions that do the right thing.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFSv4 migration needs to reassociate state owners from the source to
the destination nfs_server data structures. To make that easier, move
the cl_state_owners field to the nfs_server struct. cl_openowner_id
and cl_lockowner_id accompany this move, as they are used in
conjunction with cl_state_owners.
The cl_lock field in the parent nfs_client continues to protect all
three of these fields.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
A layout can request return-on-close. How this interacts with the
forgetful model of never sending LAYOUTRETURNS is a bit ambiguous.
We forget any layouts marked roc, and wait for them to be completely
forgotten before continuing with the close. In addition, to compensate
for races with any inflight LAYOUTGETs, and the fact that we do not get
any layout stateid back from the server, we set the barrier to the worst
case scenario of current_seqid + number of outstanding LAYOUTGETS.
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This is the heart of the wave 2 submission. Add the code to trigger
drain and forget of any afected layouts. In addition, we set a
"barrier", below which any LAYOUTGET reply is ignored. This is to
compensate for the fact that we do not wait for outstanding LAYOUTGETs
to complete as per section 12.5.5.2.1 of RFC 5661.
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This patch make nfsv4 use the generic xattr handling code
to get the nfsv4 acl. This will help us to add richacl
support to nfsv4 in later patches
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up.
The pointer returned by ->decode_dirent() is no longer used as a
pointer. The only call site (xdr_decode() in fs/nfs/dir.c) simply
extracts the errno value encoded in the pointer. Replace the
returned pointer with a standard integer errno return value.
Also, pass the "server" argument as part of the nfs_entry instead of
as a separate parameter. It's faster to derive "server" in
nfs_readdir_xdr_to_array() since we already have the directory's inode
handy. "server" ought to be invariant for a set of entries in the
same directory, right?
The legacy versions of decode_dirent() don't use "server" anyway, so
it's wasted work for them to derive and pass "server" for each entry.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Convert nfs*xdr.c to use an xdr stream in decode_dirent. This will prevent a
kernel oops that has been occuring when reading a vmapped page.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Remove references to 'struct nameidata' from the low-level open_revalidate
code, and replace them with a struct nfs_open_context which will be
correctly initialised upon success.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Start moving the 'struct nameidata' dependent code out of the lower level
NFS code in preparation for the removal of open intents.
Instead of the struct nameidata, we pass down a partially initialised
struct nfs_open_context that will be fully initialised by the atomic open
upon success.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
flock locks want to be labelled using the process pid, while posix locks
want to be labelled using the fl_owner.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This is needed by NFSv4.0 servers in order to keep the number of locking
stateids at a manageable level.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The 'so_delegations' list appears to be unused.
Also eliminate so_client. If we already have so_server, we can get to the
nfs_client structure.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In anticipation of the day when we have per-filesystem sessions, and also
in order to allow the session to change in the event of a filesystem
migration event.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We do not want to have the state recovery thread kick off and wait for a
memory reclaim, since that may deadlock when the writebacks end up
waiting for the state recovery thread to complete.
The safe thing is therefore to use GFP_NOFS in all open, close,
delegation return, lock, etc. operations that may be called by the
state recovery thread.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Drain the fore channel and reset the max_slots to the new value.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Even if the server is crazy, we should be able to mark the stateid as being
bad, to ensure it gets recovered.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
If the CLOSE or OPEN_DOWNGRADE call triggers a state recovery, and has
to be resent, then we must release the seqid. Otherwise the open
recovery will wait for the close to finish, which causes a deadlock.
This is mainly a NFSv4.1 problem, although it can theoretically happen
with NFSv4.0 too, in a OPEN_DOWNGRADE situation.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Move call to get the lease time and the setup of the state
renewal out of nfs4_create_session so that it can be called
after clearing the DRAINING flag. We use the getattr RPC
to obtain the lease time, which requires a sequence slot.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
