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path: root/fs/nfs/dir.c
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2012-11-30nfs_lookup_revalidate(): fix a leakAl Viro
We are leaking fattr and fhandle if we decide that dentry is not to be invalidated, after all (e.g. happens to be a mountpoint). Just free both before that... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-30don't do blind d_drop() in nfs_prime_dcache()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-01NFSv4: Add ACCESS operation to OPEN compoundWeston Andros Adamson
The OPEN operation has no way to differentiate an open for read and an open for execution - both look like read to the server. This allowed users to read files that didn't have READ access but did have EXEC access, which is obviously wrong. This patch adds an ACCESS call to the OPEN compound to handle the difference between OPENs for reading and execution. Since we're going through the trouble of calling ACCESS, we check all possible access bits and cache the results hopefully avoiding an ACCESS call in the future. Signed-off-by: Weston Andros Adamson <dros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-07-30NFS: Convert v4 into a moduleBryan Schumaker
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>
2012-07-30NFS: Convert v3 into a moduleBryan Schumaker
This patch exports symbols and moves over the final structures needed by the v3 module. In addition, I also switch over to using IS_ENABLED() to check if CONFIG_NFS_V3 or CONFIG_NFS_V3_MODULE are set. The module (nfs3.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 v3. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-07-30NFS: Convert v2 into a moduleBryan Schumaker
The module (nfs2.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 v2. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-07-17NFS: Split out NFS v4 inode operationsBryan Schumaker
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>
2012-07-17NFS: Split out NFS v3 inode operationsBryan Schumaker
This patch moves the NFS v3 file and directory inode functions into files that are only compiled whet CONFIG_NFS_V3 is enabled. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-07-17NFS: Split out NFS v2 inode operationsBryan Schumaker
This patch moves the NFS v2 file and directory inode functions into files that are only compiled whet CONFIG_NFS_V2 is enabled. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-07-16Merge commit '9249e17fe094d853d1ef7475dd559a2cc7e23d42' into nfs-for-3.6Trond Myklebust
Resolve conflicts with the VFS atomic open and sget changes. Conflicts: fs/nfs/nfs4proc.c
2012-07-14don't pass nameidata to ->create()Al Viro
boolean "does it have to be exclusive?" flag is passed instead; Local filesystem should just ignore it - the object is guaranteed not to be there yet. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14stop passing nameidata to ->lookup()Al Viro
Just the flags; only NFS cares even about that, but there are legitimate uses for such argument. And getting rid of that completely would require splitting ->lookup() into a couple of methods (at least), so let's leave that alone for now... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14stop passing nameidata * to ->d_revalidate()Al Viro
Just the lookup flags. Die, bastard, die... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14fs/nfs/dir.c: switch to passing nd->flags instead of nd wherever possibleAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14nfs_lookup_verify_inode() - nd is *always* non-NULL hereAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14switch nfs_lookup_check_intent() away from nameidataAl Viro
just pass the flags Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14make finish_no_open() return intAl Viro
namely, 1 ;-) That's what we want to return from ->atomic_open() instances after finish_no_open(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14kill struct opendataAl Viro
Just pass struct file *. Methods are happier that way... There's no need to return struct file * from finish_open() now, so let it return int. Next: saner prototypes for parts in namei.c Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14make ->atomic_open() return intAl Viro
Change of calling conventions: old new NULL 1 file 0 ERR_PTR(-ve) -ve Caller *knows* that struct file *; no need to return it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14->atomic_open() prototype change - pass int * instead of bool *Al Viro
... and let finish_open() report having opened the file via that sucker. Next step: don't modify od->filp at all. [AV: FILE_CREATE was already used by cifs; Miklos' fix folded] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14nfs: don't use intents for checking atomic openMiklos Szeredi
is_atomic_open() is now only used by nfs4_lookup_revalidate() to check whether it's okay to skip normal revalidation. It does a racy check for mount read-onlyness and falls back to normal revalidation if the open would fail. This makes little sense now that this function isn't used for determining whether to actually open the file or not. The d_mountpoint() check still makes sense since it is an indication that we might be following a mount and so open may not revalidate the dentry. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14nfs: don't use nd->intent.open.flagsMiklos Szeredi
Instead check LOOKUP_EXCL in nd->flags, which is basically what the open intent flags were used for. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14nfs: clean up ->create in nfs_rpc_opsMiklos Szeredi
Don't pass nfs_open_context() to ->create(). Only the NFS4 implementation needed that and only because it wanted to return an open file using open intents. That task has been replaced by ->atomic_open so it is not necessary anymore to pass the context to the create rpc operation. Despite nfs4_proc_create apparently being okay with a NULL context it Oopses somewhere down the call chain. So allocate a context here. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14nfs: implement i_op->atomic_open()Miklos Szeredi
Replace NFS4 specific ->lookup implementation with ->atomic_open impelementation and use the generic nfs_lookup for other lookups. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-29NFS: Create a return_delegation rpc opBryan Schumaker
Delegations are a v4 feature, so push return_delegation out of the generic client by creating a new rpc_op and renaming the old function to be in the nfs v4 "namespace" Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-06-29NFS: Create a have_delegation rpc_opBryan Schumaker
Delegations are a v4 feature, so push them out of the generic code. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-06-01nfs: don't open in ->d_revalidateMiklos Szeredi
NFSv4 can't do reliable opens in d_revalidate, since it cannot know whether a mount needs to be followed or not. It does check d_mountpoint() on the dentry, which can result in a weird error if the VFS found that the mount does not in fact need to be followed, e.g.: # mount --bind /mnt/nfs /mnt/nfs-clone # echo something > /mnt/nfs/tmp/bar # echo x > /tmp/file # mount --bind /tmp/file /mnt/nfs-clone/tmp/bar # cat /mnt/nfs/tmp/bar cat: /mnt/nfs/tmp/bar: Not a directory Which should, by any sane filesystem, result in "something" being printed. So instead do the open in f_op->open() and in the unlikely case that the cached dentry turned out to be invalid, drop the dentry and return EOPENSTALE to let the VFS retry. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> CC: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-29Merge tag 'nfs-for-3.5-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
Pull NFS client updates from Trond Myklebust: "New features include: - Rewrite the O_DIRECT code so that it can share the same coalescing and pNFS functionality as the page cache code. - Allow the server to provide hints as to when we should use pNFS, and when it is more efficient to read and write through the metadata server. - NFS cache consistency updates: * Use the ctime to emulate a change attribute for NFSv2/v3 so that all NFS versions can share the same cache management code. * New cache management code will only look at the change attribute and size attribute when deciding whether or not our cached data is still valid or not. * Don't request NFSv4 post-op attributes on writes in cases such as O_DIRECT, where we don't care about data cache consistency, or when we have a write delegation, and know that our cache is still consistent. * Don't request NFSv4 post-op attributes on operations such as COMMIT, where there are no expected metadata updates. * Don't request NFSv4 directory post-op attributes in cases where the operations themselves already return change attribute updates: i.e. operations such as OPEN, CREATE, REMOVE, LINK and RENAME. - Speed up 'ls' and friends by using READDIR rather than READDIRPLUS if we detect no attempts to lookup filenames. - Improve the code sharing between NFSv2/v3 and v4 mounts - NFSv4.1 state management efficiency improvements - More patches in preparation for NFSv4/v4.1 migration functionality." Fix trivial conflict in fs/nfs/nfs4proc.c that was due to the dcache qstr name initialization changes (that made the length/hash a 64-bit union) * tag 'nfs-for-3.5-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (146 commits) NFSv4: Add debugging printks to state manager NFSv4: Map NFS4ERR_SHARE_DENIED into an EACCES error instead of EIO NFSv4: update_changeattr does not need to set NFS_INO_REVAL_PAGECACHE NFSv4.1: nfs4_reset_session should use nfs4_handle_reclaim_lease_error NFSv4.1: Handle other occurrences of NFS4ERR_CONN_NOT_BOUND_TO_SESSION NFSv4.1: Handle NFS4ERR_CONN_NOT_BOUND_TO_SESSION in the state manager NFSv4.1: Handle errors in nfs4_bind_conn_to_session NFSv4.1: nfs4_bind_conn_to_session should drain the session NFSv4.1: Don't clobber the seqid if exchange_id returns a confirmed clientid NFSv4.1: Add DESTROY_CLIENTID NFSv4.1: Ensure we use the correct credentials for bind_conn_to_session NFSv4.1: Ensure we use the correct credentials for session create/destroy NFSv4.1: Move NFSPROC4_CLNT_BIND_CONN_TO_SESSION to the end of the operations NFSv4.1: Handle NFS4ERR_SEQ_MISORDERED when confirming the lease NFSv4: When purging the lease, we must clear NFS4CLNT_LEASE_CONFIRM NFSv4: Clean up the error handling for nfs4_reclaim_lease NFSv4.1: Exchange ID must use GFP_NOFS allocation mode nfs41: Use BIND_CONN_TO_SESSION for CB_PATH_DOWN* nfs4.1: add BIND_CONN_TO_SESSION operation NFSv4.1 test the mdsthreshold hint parameters ...
2012-05-11vfs: make it possible to access the dentry hash/len as one 64-bit entryLinus Torvalds
This allows comparing hash and len in one operation on 64-bit architectures. Right now only __d_lookup_rcu() takes advantage of this, since that is the case we care most about. The use of anonymous struct/unions hides the alternate 64-bit approach from most users, the exception being a few cases where we initialize a 'struct qstr' with a static initializer. This makes the problematic cases use a new QSTR_INIT() helper function for that (but initializing just the name pointer with a "{ .name = xyzzy }" initializer remains valid, as does just copying another qstr structure). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-01NFS: Adapt readdirplus to application usage patternsTrond Myklebust
While the use of READDIRPLUS is significantly more efficient than READDIR followed by many LOOKUP calls, it is still less efficient than just READDIR if the attributes are not required. This patch tracks when lookups are attempted on the directory, and uses that information to selectively disable READDIRPLUS on that directory. The first 'readdir' call is always served using READDIRPLUS. Subsequent calls only use READDIRPLUS if there was a successful lookup or revalidation on a child in the mean time. Credit for the original idea should go to Neil Brown. See: http://www.spinics.net/lists/linux-nfs/msg19996.html However, the implementation in this patch differs from Neil's in that it focuses on tracking lookups rather than calls to stat(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Neil Brown <neilb@suse.de>
2012-04-27NFS: Remove extra rpc_clnt argument to proc_lookupBryan Schumaker
Now that I'm doing secinfo automatically in the v4 code this extra argument isn't needed. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-04-19NFSv4: Fix open(O_TRUNC) and ftruncate() error handlingTrond Myklebust
If the file wasn't opened for writing, then truncate and ftruncate need to report the appropriate errors. Reported-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: stable@vger.kernel.org
2012-03-23Merge tag 'nfs-for-3.4-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds
Pull NFS client updates for Linux 3.4 from Trond Myklebust: "New features include: - Add NFS client support for containers. This should enable most of the necessary functionality, including lockd support, and support for rpc.statd, NFSv4 idmapper and RPCSEC_GSS upcalls into the correct network namespace from which the mount system call was issued. - NFSv4 idmapper scalability improvements Base the idmapper cache on the keyring interface to allow concurrent access to idmapper entries. Start the process of migrating users from the single-threaded daemon-based approach to the multi-threaded request-key based approach. - NFSv4.1 implementation id. Allows the NFSv4.1 client and server to mutually identify each other for logging and debugging purposes. - Support the 'vers=4.1' mount option for mounting NFSv4.1 instead of having to use the more counterintuitive 'vers=4,minorversion=1'. - SUNRPC tracepoints. Start the process of adding tracepoints in order to improve debugging of the RPC layer. - pNFS object layout support for autologin. Important bugfixes include: - Fix a bug in rpc_wake_up/rpc_wake_up_status that caused them to fail to wake up all tasks when applied to priority waitqueues. - Ensure that we handle read delegations correctly, when we try to truncate a file. - A number of fixes for NFSv4 state manager loops (mostly to do with delegation recovery)." * tag 'nfs-for-3.4-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (224 commits) NFS: fix sb->s_id in nfs debug prints xprtrdma: Remove assumption that each segment is <= PAGE_SIZE xprtrdma: The transport should not bug-check when a dup reply is received pnfs-obj: autologin: Add support for protocol autologin NFS: Remove nfs4_setup_sequence from generic rename code NFS: Remove nfs4_setup_sequence from generic unlink code NFS: Remove nfs4_setup_sequence from generic read code NFS: Remove nfs4_setup_sequence from generic write code NFS: Fix more NFS debug related build warnings SUNRPC/LOCKD: Fix build warnings when CONFIG_SUNRPC_DEBUG is undefined nfs: non void functions must return a value SUNRPC: Kill compiler warning when RPC_DEBUG is unset SUNRPC/NFS: Add Kbuild dependencies for NFS_DEBUG/RPC_DEBUG NFS: Use cond_resched_lock() to reduce latencies in the commit scans NFSv4: It is not safe to dereference lsp->ls_state in release_lockowner NFS: ncommit count is being double decremented SUNRPC: We must not use list_for_each_entry_safe() in rpc_wake_up() Try using machine credentials for RENEW calls NFSv4.1: Fix a few issues in filelayout_commit_pagelist NFSv4.1: Clean ups and bugfixes for the pNFS read/writeback/commit code ...
2012-03-20nfs: remove the second argument of k[un]map_atomic()Cong Wang
Signed-off-by: Cong Wang <amwang@redhat.com>
2012-03-02NFS: Make nfs_cache_array.size a signed integerChuck Lever
Eliminate a number of implicit type casts in comparisons, and these compiler warnings: fs/nfs/dir.c: In function ‘nfs_readdir_clear_array’: fs/nfs/dir.c:264:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] fs/nfs/dir.c: In function ‘nfs_readdir_search_for_cookie’: fs/nfs/dir.c:352:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] fs/nfs/dir.c: In function ‘nfs_do_filldir’: fs/nfs/dir.c:769:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] fs/nfs/dir.c:780:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-01NFS: Optimise away unnecessary setattrs for open(O_TRUNC);Trond Myklebust
Currently, we will correctly optimise away a truncate that doesn't change the file size. However, in the case of open(O_TRUNC), we also want to optimise away the time changes. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-04switch ->mknod() to umode_tAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-04switch ->create() to umode_tAl Viro
vfs_create() ignores everything outside of 16bit subset of its mode argument; switching it to umode_t is obviously equivalent and it's the only caller of the method Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-04switch vfs_mkdir() and ->mkdir() to umode_tAl Viro
vfs_mkdir() gets int, but immediately drops everything that might not fit into umode_t and that's the only caller of ->mkdir()... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-04pull manipulations of rpc_cred inside alloc_nfs_open_context()Al Viro
No need to duplicate them in both callers; make it return ERR_PTR(-ENOMEM) on allocation failure instead of NULL and it'll be able to report rpc_lookup_cred() failures just fine. Callers are much happier that way... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-11-04nfs: when attempting to open a directory, fall back on normal lookup (try #5)Jeff Layton
commit d953126 changed how nfs_atomic_lookup handles an -EISDIR return from an OPEN call. Prior to that patch, that caused the client to fall back to doing a normal lookup. When that patch went in, the code began returning that error to userspace. The d_revalidate codepath however never had the corresponding change, so it was still possible to end up with a NULL ctx->state pointer after that. That patch caused a regression. When we attempt to open a directory that does not have a cached dentry, that open now errors out with EISDIR. If you attempt the same open with a cached dentry, it will succeed. Fix this by reverting the change in nfs_atomic_lookup and allowing attempts to open directories to fall back to a normal lookup Also, add a NFSv4-specific f_ops->open routine that just returns -ENOTDIR. This should never be called if things are working properly, but if it ever is, then the dprintk may help in debugging. To facilitate this, a new file_operations field is also added to the nfs_rpc_ops struct. Cc: stable@kernel.org Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-30Additional readdir cookie loop informationBryan Schumaker
Print out the name of the file that triggers the cookie loop message to make it slightly easier to track down the cause. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-30NFS: Fix spurious readdir cookie loop messagesTrond Myklebust
If the directory contents change, then we have to accept that the file->f_pos value may shrink if we do a 'search-by-cookie'. In that case, we should turn off the loop detection and let the NFS client try to recover. The patch also fixes a second loop detection bug by ensuring that after turning on the ctx->duped flag, we read at least one new cookie into ctx->dir_cookie before attempting to match with ctx->dup_cookie. Reported-by: Petr Vandrovec <petr@vandrovec.name> Cc: stable@kernel.org [2.6.39+] Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-21fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlersJosef Bacik
Btrfs needs to be able to control how filemap_write_and_wait_range() is called in fsync to make it less of a painful operation, so push down taking i_mutex and the calling of filemap_write_and_wait() down into the ->fsync() handlers. Some file systems can drop taking the i_mutex altogether it seems, like ext3 and ocfs2. For correctness sake I just pushed everything down in all cases to make sure that we keep the current behavior the same for everybody, and then each individual fs maintainer can make up their mind about what to do from there. Thanks, Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20nfs: LOOKUP_{OPEN,CREATE,EXCL} is set only on the last stepAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20no need to check for LOOKUP_OPEN in ->create() instancesAl Viro
... it will be set in nd->flag for all cases with non-NULL nd (i.e. when called from do_last()). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20don't transliterate lower bits of ->intent.open.flags to FMODE_...Al Viro
->create() instances are much happier that way... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20fix mknod() on nfs4 (hopefully)Al Viro
a) check the right flags in ->create() (LOOKUP_OPEN, not LOOKUP_CREATE) b) default (!LOOKUP_OPEN) open_flags is O_CREAT|O_EXCL|FMODE_READ, not 0 c) lookup_instantiate_filp() should be done only with LOOKUP_OPEN; otherwise we need to issue CLOSE, lest we leak stateid on server. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20nameidata_to_nfs_open_context() doesn't need nameidata, actually...Al Viro
just open flags; switched to passing just those and renamed to create_nfs_open_context() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20nfs_open_context doesn't need struct path eitherAl Viro
just dentry, please... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>