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path: root/fs/nfs/nfs4proc.c
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2007-07-10NFSv4: Make sure unlock is really an unlock when cancelling a lockFrank Filz
I ran into a curious issue when a lock is being canceled. The cancellation results in a lock request to the vfs layer instead of an unlock request. This is particularly insidious when the process that owns the lock is exiting. In that case, sometimes the erroneous lock is applied AFTER the process has entered zombie state, preventing the lock from ever being released. Eventually other processes block on the lock causing a slow degredation of the system. In the 2.6.16 kernel this was investigated on, the problem is compounded by the fact that the cl_sem is held while blocking on the vfs lock, which results in most processes accessing the nfs file system in question hanging. In more detail, here is how the situation occurs: first _nfs4_do_setlk(): static int _nfs4_do_setlk(struct nfs4_state *state, int cmd, struct file_lock *fl, int reclaim) ... ret = nfs4_wait_for_completion_rpc_task(task); if (ret == 0) { ... } else data->cancelled = 1; then nfs4_lock_release(): static void nfs4_lock_release(void *calldata) ... if (data->cancelled != 0) { struct rpc_task *task; task = nfs4_do_unlck(&data->fl, data->ctx, data->lsp, data->arg.lock_seqid); The problem is the same file_lock that was passed in to _nfs4_do_setlk() gets passed to nfs4_do_unlck() from nfs4_lock_release(). So the type is still F_RDLCK or FWRLCK, not F_UNLCK. At some point, when cancelling the lock, the type needs to be changed to F_UNLCK. It seemed easiest to do that in nfs4_do_unlck(), but it could be done in nfs4_lock_release(). The concern I had with doing it there was if something still needed the original file_lock, though it turns out the original file_lock still needs to be modified by nfs4_do_unlck() because nfs4_do_unlck() uses the original file_lock to pass to the vfs layer, and a copy of the original file_lock for the RPC request. It seems like the simplest solution is to force all situations where nfs4_do_unlck() is being used to result in an unlock, so with that in mind, I made the following change: Signed-off-by: Frank Filz <ffilzlnx@us.ibm.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Fix up stateid locking...Trond Myklebust
We really don't need to grab both the state->so_owner and the inode->i_lock. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Clean up the callers of nfs4_open_recover_helper()Trond Myklebust
Rely on nfs4_try_open_cached() when appropriate. Also fix an RCU violation in _nfs4_do_open_reclaim() Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Don't call OPEN if we already have an open stateid for a fileTrond Myklebust
If we already have a stateid with the correct open mode for a given file, then we can reuse that stateid instead of re-issuing an OPEN call without violating the close-to-open caching semantics. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Check for the existence of a delegation in nfs4_open_prepare()Trond Myklebust
We should not be calling open() on an inode that has a delegation unless we're doing a reclaim. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Clean up _nfs4_proc_open()Trond Myklebust
Use a flag instead of the 'data->rpc_status = -ENOMEM hack. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Allow nfs4_opendata_to_nfs4_state to return errors.Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Improve the debugging of bad sequence id errors...Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Always use the delegation if we have oneTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Clean up confirmation of sequence ids...Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Support recalling delegations by stateid part 2Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Fix up a bug in nfs4_open_recover()Trond Myklebust
Don't clobber the delegation info... Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: set the delegation in nfs4_opendata_to_nfs4_stateTrond Myklebust
This ensures that nfs4_open_release() and nfs4_open_confirm_release() can now handle an eventual delegation that was returned with out open. As such, it fixes a delegation "leak" when the user breaks out of an open call. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Fix atomic open for execute...Trond Myklebust
Currently we do not check for the FMODE_EXEC flag as we should. For that particular case, we need to perform an ACCESS call to the server in order to check that the file is executable. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Reduce the chances of an open_owner identifier collisionTrond Myklebust
Currently we just use a 32-bit counter. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Clean up _nfs4_proc_lookup() vs _nfs4_proc_lookupfh()Trond Myklebust
They differ only slightly in the arguments they take. Why have they not been merged? Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Convert struct nfs4_opendata to use struct krefTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFS4: on a O_EXCL OPEN make sure SETATTR sets the fields holding the verifierJeff Layton
The Linux NFS4 client simply skips over the bitmask in an O_EXCL open call and so it doesn't bother to reset any fields that may be holding the verifier. This patch has us save the first two words of the bitmask (which is all the current client has #defines for). The client then later checks this bitmask and turns on the appropriate flags in the sattr->ia_verify field for the following SETATTR call. This patch only currently checks to see if the server used the atime and mtime slots for the verifier (which is what the Linux server uses for this). I'm not sure of what other fields the server could reasonably use, but adding checks for others should be trivial. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Clean up nfs4_call_async()Trond Myklebust
Use rpc_run_task() instead of doing it ourselves. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Ensure that nfs4_do_close() doesn't race with umountTrond Myklebust
nfs4_do_close() does not currently have any way to ensure that the user won't attempt to unmount the partition while the asynchronous RPC call is completing. This again may cause Oopses in nfs_update_inode(). Add a vfsmount argument to nfs4_close_state to ensure that the partition remains mounted while we're closing the file. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Ensure asynchronous open() calls always pin the mountpointTrond Myklebust
A number of race conditions may currently ensue if the user presses ^C and then unmounts the partition while an asynchronous open() is in progress. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFSv4: Cleanup: pass the nfs_open_context to open recovery codeTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-07-10NFS: Replace vfsmount and dentry in nfs_open_context with struct pathTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-05-14NFS: Fix some 'sparse' warnings...Trond Myklebust
- fs/nfs/dir.c:610:8: warning: symbol 'nfs_llseek_dir' was not declared. Should it be static? - fs/nfs/dir.c:636:5: warning: symbol 'nfs_fsync_dir' was not declared. Should it be static? - fs/nfs/write.c:925:19: warning: symbol 'req' shadows an earlier one - fs/nfs/write.c:61:6: warning: symbol 'nfs_commit_rcu_free' was not declared. Should it be static? - fs/nfs/nfs4proc.c:793:5: warning: symbol 'nfs4_recover_expired_lease' was not declared. Should it be static? Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-05-07Merge branch 'server-cluster-locking-api' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
* 'server-cluster-locking-api' of git://linux-nfs.org/~bfields/linux: gfs2: nfs lock support for gfs2 lockd: add code to handle deferred lock requests lockd: always preallocate block in nlmsvc_lock() lockd: handle test_lock deferrals lockd: pass cookie in nlmsvc_testlock lockd: handle fl_grant callbacks lockd: save lock state on deferral locks: add fl_grant callback for asynchronous lock return nfsd4: Convert NFSv4 to new lock interface locks: add lock cancel command locks: allow {vfs,posix}_lock_file to return conflicting lock locks: factor out generic/filesystem switch from setlock code locks: factor out generic/filesystem switch from test_lock locks: give posix_test_lock same interface as ->lock locks: make ->lock release private data before returning in GETLK case locks: create posix-to-flock helper functions locks: trivial removal of unnecessary parentheses
2007-05-06locks: make ->lock release private data before returning in GETLK caseJ. Bruce Fields
The file_lock argument to ->lock is used to return the conflicting lock when found. There's no reason for the filesystem to return any private information with this conflicting lock, but nfsv4 is. Fix nfsv4 client, and modify locks.c to stop calling fl_release_private for it in this case. Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu> Cc: "Trond Myklebust" <Trond.Myklebust@netapp.com>"
2007-05-02NFS4: invalidate cached acl on setaclJ. Bruce Fields
The ACL that the server sets may not be exactly the one we set--for example, it may silently turn off bits that it does not support. So we should remove any cached ACL so that any subsequent request for the ACL will go to the server. Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-02-12Merge branch 'master' of /home/trondmy/kernel/linux-2.6/Trond Myklebust
Conflicts: net/sunrpc/auth_gss/gss_krb5_crypto.c net/sunrpc/auth_gss/gss_spkm3_token.c net/sunrpc/clnt.c Merge with mainline and fix conflicts.
2007-02-12[PATCH] mark struct inode_operations const 2Arjan van de Ven
Many struct inode_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-03NFSv4: Add lockdep checks to nfs4_wait_clnt_recover()Trond Myklebust
Attempt to detect deadlocks due to caller holding locks on clp->cl_sem Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-02-03NFSv4: Don't start state recovery in nfs4_close_done()Trond Myklebust
We might not even have any open files at this point... Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-02-03NFS: Remove nfs_readpage_sync()Trond Myklebust
It makes no sense to maintain 2 parallel systems for reading in pages. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-02-03NFSv4: Cleanups for fs_locations code.Trond Myklebust
Start long arduous project... What the hell is struct dentry = {}; all about? Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-12-13[PATCH] getting rid of all casts of k[cmz]alloc() callsRobert P. J. Day
Run this: #!/bin/sh for f in $(grep -Erl "\([^\)]*\) *k[cmz]alloc" *) ; do echo "De-casting $f..." perl -pi -e "s/ ?= ?\([^\)]*\) *(k[cmz]alloc) *\(/ = \1\(/" $f done And then go through and reinstate those cases where code is casting pointers to non-pointers. And then drop a few hunks which conflicted with outstanding work. Cc: Russell King <rmk@arm.linux.org.uk>, Ian Molton <spyro@f2s.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Greg KH <greg@kroah.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Paul Fulghum <paulkf@microgate.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Karsten Keil <kkeil@suse.de> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Jeff Garzik <jeff@garzik.org> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Ian Kent <raven@themaw.net> Cc: Steven French <sfrench@us.ibm.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Neil Brown <neilb@cse.unsw.edu.au> Cc: Jaroslav Kysela <perex@suse.cz> Cc: Takashi Iwai <tiwai@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-06NFS: Remove nfs_writepage_sync()Trond Myklebust
Maintaining two parallel ways of doing synchronous writes is rather pointless. This patch gets rid of the legacy nfs_writepage_sync(), and replaces it with the faster asynchronous writes. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-12-06NFS: Remove use of the Big Kernel Lock around calls to rpc_call_syncFrank Filz
Remove use of the Big Kernel Lock around calls to rpc_call_sync. Signed-off-by: Frank Filz <ffilz@us.ibm.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-12-06Fix a second potential rpc_wakeup race...Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-10-20[PATCH] nfs: verifier is network-endianAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no> Acked-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20[PATCH] xdr annotations: NFS readdir entriesAl Viro
on-the-wire data is big-endian [in large part pulled from Alexey's patch] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no> Acked-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20[PATCH] NFS: remove unused check in nfs4_open_revalidateChuck Lever
Coverity spotted a superfluous error check in nfs4_open_revalidate(). Remove it. Coverity: #cid 847 Test plan: Code inspection; another pass through Coverity. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-22NFSv4: Poll more aggressively when handling NFS4ERR_DELAYTrond Myklebust
Change the initial retry delay from 1s to 0.1s (and then back off exponentially). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22NFSv4: Handle the condition NFS4ERR_FILE_OPENTrond Myklebust
Retry a few times before we give up: the error is usually due to ordering issues with asynchronous RPC calls. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22NFSv4: Retry lease recovery if it failed during a synchronous operation.Trond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22NFS: Use cached page as buffer for NFS symlink requestsChuck Lever
Now that we have a copy of the symlink path in the page cache, we can pass a struct page down to the XDR routines instead of a string buffer. Test plan: Connectathon, all NFS versions. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22NFS: Fix double d_drop in nfs_instantiate() error pathChuck Lever
If the LOOKUP or GETATTR in nfs_instantiate fail, nfs_instantiate will do a d_drop before returning. But some callers already do a d_drop in the case of an error return. Make certain we do only one d_drop in all error paths. This issue was introduced because over time, the symlink proc API diverged slightly from the create/mkdir/mknod proc API. To prevent other coding mistakes of this type, change the symlink proc API to be more like create/mkdir/mknod and move the nfs_instantiate call into the symlink proc routines so it is used in exactly the same way for create, mkdir, mknod, and symlink. Test plan: Connectathon, all versions of NFS. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22NFS: Share NFS superblocks per-protocol per-server per-FSIDDavid Howells
The attached patch makes NFS share superblocks between mounts from the same server and FSID over the same protocol. It does this by creating each superblock with a false root and returning the real root dentry in the vfsmount presented by get_sb(). The root dentry set starts off as an anonymous dentry if we don't already have the dentry for its inode, otherwise it simply returns the dentry we already have. We may thus end up with several trees of dentries in the superblock, and if at some later point one of anonymous tree roots is discovered by normal filesystem activity to be located in another tree within the superblock, the anonymous root is named and materialises attached to the second tree at the appropriate point. Why do it this way? Why not pass an extra argument to the mount() syscall to indicate the subpath and then pathwalk from the server root to the desired directory? You can't guarantee this will work for two reasons: (1) The root and intervening nodes may not be accessible to the client. With NFS2 and NFS3, for instance, mountd is called on the server to get the filehandle for the tip of a path. mountd won't give us handles for anything we don't have permission to access, and so we can't set up NFS inodes for such nodes, and so can't easily set up dentries (we'd have to have ghost inodes or something). With this patch we don't actually create dentries until we get handles from the server that we can use to set up their inodes, and we don't actually bind them into the tree until we know for sure where they go. (2) Inaccessible symbolic links. If we're asked to mount two exports from the server, eg: mount warthog:/warthog/aaa/xxx /mmm mount warthog:/warthog/bbb/yyy /nnn We may not be able to access anything nearer the root than xxx and yyy, but we may find out later that /mmm/www/yyy, say, is actually the same directory as the one mounted on /nnn. What we might then find out, for example, is that /warthog/bbb was actually a symbolic link to /warthog/aaa/xxx/www, but we can't actually determine that by talking to the server until /warthog is made available by NFS. This would lead to having constructed an errneous dentry tree which we can't easily fix. We can end up with a dentry marked as a directory when it should actually be a symlink, or we could end up with an apparently hardlinked directory. With this patch we need not make assumptions about the type of a dentry for which we can't retrieve information, nor need we assume we know its place in the grand scheme of things until we actually see that place. This patch reduces the possibility of aliasing in the inode and page caches for inodes that may be accessed by more than one NFS export. It also reduces the number of superblocks required for NFS where there are many NFS exports being used from a server (home directory server + autofs for example). This in turn makes it simpler to do local caching of network filesystems, as it can then be guaranteed that there won't be links from multiple inodes in separate superblocks to the same cache file. Obviously, cache aliasing between different levels of NFS protocol could still be a problem, but at least that gives us another key to use when indexing the cache. This patch makes the following changes: (1) The server record construction/destruction has been abstracted out into its own set of functions to make things easier to get right. These have been moved into fs/nfs/client.c. All the code in fs/nfs/client.c has to do with the management of connections to servers, and doesn't touch superblocks in any way; the remaining code in fs/nfs/super.c has to do with VFS superblock management. (2) The sequence of events undertaken by NFS mount is now reordered: (a) A volume representation (struct nfs_server) is allocated. (b) A server representation (struct nfs_client) is acquired. This may be allocated or shared, and is keyed on server address, port and NFS version. (c) If allocated, the client representation is initialised. The state member variable of nfs_client is used to prevent a race during initialisation from two mounts. (d) For NFS4 a simple pathwalk is performed, walking from FH to FH to find the root filehandle for the mount (fs/nfs/getroot.c). For NFS2/3 we are given the root FH in advance. (e) The volume FSID is probed for on the root FH. (f) The volume representation is initialised from the FSINFO record retrieved on the root FH. (g) sget() is called to acquire a superblock. This may be allocated or shared, keyed on client pointer and FSID. (h) If allocated, the superblock is initialised. (i) If the superblock is shared, then the new nfs_server record is discarded. (j) The root dentry for this mount is looked up from the root FH. (k) The root dentry for this mount is assigned to the vfsmount. (3) nfs_readdir_lookup() creates dentries for each of the entries readdir() returns; this function now attaches disconnected trees from alternate roots that happen to be discovered attached to a directory being read (in the same way nfs_lookup() is made to do for lookup ops). The new d_materialise_unique() function is now used to do this, thus permitting the whole thing to be done under one set of locks, and thus avoiding any race between mount and lookup operations on the same directory. (4) The client management code uses a new debug facility: NFSDBG_CLIENT which is set by echoing 1024 to /proc/net/sunrpc/nfs_debug. (5) Clone mounts are now called xdev mounts. (6) Use the dentry passed to the statfs() op as the handle for retrieving fs statistics rather than the root dentry of the superblock (which is now a dummy). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22NFS: Move rpc_ops from nfs_server to nfs_clientDavid Howells
Move the rpc_ops from the nfs_server struct to the nfs_client struct as they're common to all server records of a particular NFS protocol version. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22NFS: Make better use of inode* dereferencing macrosDavid Howells
Make better use of inode* dereferencing macros to hide dereferencing chains (including NFS_PROTO and NFS_CLIENT). Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22NFS: Add extra const qualifiersDavid Howells
Add some extra const qualifiers into NFS. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22NFS: Generalise the nfs_client structureDavid Howells
Generalise the nfs_client structure by: (1) Moving nfs_client to a more general place (nfs_fs_sb.h). (2) Renaming its maintenance routines to be non-NFS4 specific. (3) Move those maintenance routines to a new non-NFS4 specific file (client.c) and move the declarations to internal.h. (4) Make nfs_find/get_client() take a full sockaddr_in to include the port number (will be required for NFS2/3). (5) Make nfs_find/get_client() take the NFS protocol version (again will be required to differentiate NFS2, 3 & 4 client records). Also: (6) Make nfs_client construction proceed akin to inodes, marking them as under construction and providing a function to indicate completion. (7) Make nfs_get_client() wait interruptibly if it finds a client that it can share, but that client is currently being constructed. (8) Make nfs4_create_client() use (6) and (7) instead of locking cl_sem. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>