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* Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6Linus Torvalds2010-04-291-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | * 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: nfs: fix memory leak in nfs_get_sb with CONFIG_NFS_V4 nfs: fix some issues in nfs41_proc_reclaim_complete() NFS: Ensure that nfs_wb_page() waits for Pg_writeback to clear NFS: Fix an unstable write data integrity race nfs: testing for null instead of ERR_PTR() NFS: rsize and wsize settings ignored on v4 mounts NFSv4: Don't attempt an atomic open if the file is a mountpoint SUNRPC: Fix a bug in rpcauth_prune_expired
| * NFSv4: Don't attempt an atomic open if the file is a mountpointTrond Myklebust2010-04-221-1/+1
| | | | | | | | | | | | Fix https://bugzilla.kernel.org/show_bug.cgi?id=15789 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* | nfs d_revalidate() is too trigger-happy with d_drop()Al Viro2010-04-281-0/+2
|/ | | | | | | | | | | | | | | If dentry found stale happens to be a root of disconnected tree, we can't d_drop() it; its d_hash is actually part of s_anon and d_drop() would simply hide it from shrink_dcache_for_umount(), leading to all sorts of fun, including busy inodes on umount and oopsen after that. Bug had been there since at least 2006 (commit c636eb already has it), so it's definitely -stable fodder. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* NFSv4: Fall back to ordinary lookup if nfs4_atomic_open() returns EISDIRTrond Myklebust2010-04-091-1/+1
| | | | | Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: stable@kernel.org
* NFSv4: Don't ignore the NFS_INO_REVAL_FORCED flag in nfs_revalidate_inode()Trond Myklebust2010-03-101-1/+1
| | | | | | | | | If the NFS_INO_REVAL_FORCED flag is set, that means that we don't yet have an up to date attribute cache. Even if we hold a delegation, we must put a GETATTR on the wire. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: stable@kernel.org
* NFS: Remove requirement for inode->i_mutex from nfs_invalidate_mappingTrond Myklebust2010-03-051-1/+1
| | | | Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* nfs: fix oops in nfs_rename()OGAWA Hirofumi2010-01-061-0/+1
| | | | | | | | | | | | | | Recent change is missing to update "rehash". With that change, it will become the cause of adding dentry to hash twice. This explains the reason of Oops (dereference the freed dentry in __d_lookup()) on my machine. Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Reported-by: Marvin <marvin24@gmx.de> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* nfs: clean up sillyrenaming in nfs_rename()Miklos Szeredi2009-12-031-7/+4
| | | | | | | | | | | | The d_instantiate(new_dentry, NULL) is superfluous, the dentry is already negative. Rehashing this dummy dentry isn't needed either, d_move() works fine on an unhashed target. The re-checking for busy after a failed nfs_sillyrename() is bogus too: new_dentry->d_count < 2 would be a bug here. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* nfs: dont unhash target if renaming a directoryMiklos Szeredi2009-12-031-27/+29
| | | | | | | | | | | | Move unhashing the target to after the check for existence and being a non-directory. If renaming a directory then the VFS already unhashes the target if it is not busy. If it's busy then acquiring more references during the rename makes no difference. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* nfs: fix comments in nfs_rename()Miklos Szeredi2009-12-031-7/+5
| | | | | | | | | Comments are wrong or out of date. In particular d_drop() doesn't free the inode it just unhashes the dentry. And if target is a directory then it is not checked for being busy. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* nfs: remove unnecessary check from nfs_rename()Miklos Szeredi2009-12-031-8/+2
| | | | | | | VFS already checks if both source and target are directories. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFSv4: The link() operation should return any delegation on the fileTrond Myklebust2009-10-261-0/+2
| | | | | | Otherwise, we have to wait for the server to recall it. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFSv4: Fix a problem whereby a buggy server can oops the kernelTrond Myklebust2009-07-211-1/+1
| | | | | | | | | | | | | | | | | | We just had a case in which a buggy server occasionally returns the wrong attributes during an OPEN call. While the client does catch this sort of condition in nfs4_open_done(), and causes the nfs4_atomic_open() to return -EISDIR, the logic in nfs_atomic_lookup() is broken, since it causes a fallback to an ordinary lookup instead of just returning the error. When the buggy server then returns a regular file for the fallback lookup, the VFS allows the open, and bad things start to happen, since the open file doesn't have any associated NFSv4 state. The fix is firstly to return the EISDIR/ENOTDIR errors immediately, and secondly to ensure that we are always careful when dereferencing the nfs_open_context state pointer. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* headers: smp_lock.h reduxAlexey Dobriyan2009-07-121-1/+0
| | | | | | | | | | | | | * Remove smp_lock.h from files which don't need it (including some headers!) * Add smp_lock.h to files which do need it * Make smp_lock.h include conditional in hardirq.h It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT This will make hardirq.h inclusion cheaper for every PREEMPT=n config (which includes allmodconfig/allyesconfig, BTW) Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* nfs: Fix NFS v4 client handling of MAY_EXEC in nfs_permission.Frank Filz2009-05-181-1/+2
| | | | | | | | | | | | | | | | | | | The problem is that permission checking is skipped if atomic open is possible, but when exec opens a file, it just opens it O_READONLY which means EXEC permission will not be checked at that time. This problem is observed by the following sequence (executed as root): mount -t nfs4 server:/ /mnt4 echo "ls" >/mnt4/foo chmod 744 /mnt4/foo su guest -c "mnt4/foo" Signed-off-by: Frank Filz <ffilzlnx@us.ibm.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: stable@kernel.org Tested-by: Eugene Teo <eugeneteo@kernel.sg> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'devel' into for-linusTrond Myklebust2009-04-011-5/+4
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| * NFS: Fix the notifications when renaming onto an existing fileTrond Myklebust2009-03-191-5/+4
| | | | | | | | | | | | | | | | | | | | | | NFS appears to be returning an unnecessary "delete" notification when we're doing an atomic rename. See http://bugzilla.gnome.org/show_bug.cgi?id=575684 The fix is to get rid of the redundant call to d_delete(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* | constify dentry_operations: NFSAl Viro2009-03-271-2/+2
|/ | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* NFS: Handle -ESTALE error in access()Suresh Jayaraman2009-03-101-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Hi Trond, I have been looking at a bugreport where trying to open applications on KDE on a NFS mounted home fails temporarily. There have been multiple reports on different kernel versions pointing to this common issue: http://bugzilla.kernel.org/show_bug.cgi?id=12557 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/269954 http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=508866.html This issue can be reproducible consistently by doing this on a NFS mounted home (KDE): 1. Open 2 xterm sessions 2. From one of the xterm session, do "ssh -X <remote host>" 3. "stat ~/.Xauthority" on the remote SSH session 4. Close the two xterm sessions 5. On the server do a "stat ~/.Xauthority" 6. Now on the client, try to open xterm This will fail. Even if the filehandle had become stale, the NFS client should invalidate the cache/inode and should repeat LOOKUP. Looking at the packet capture when the failure occurs shows that there were two subsequent ACCESS() calls with the same filehandle and both fails with -ESTALE error. I have tested the fix below. Now the client issue a LOOKUP after the ACCESS() call fails with -ESTALE. If all this makes sense to you, can you consider this for inclusion? Thanks, If the server returns an -ESTALE error due to stale filehandle in response to an ACCESS() call, we need to invalidate the cache and inode so that LOOKUP() can be retried. Without this change, the nfs client retries ACCESS() with the same filehandle, fails again and could lead to temporary failure of applications running on nfs mounted home. Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* optimize attribute timeouts for "noac" and "actimeo=0"Peter Staubach2008-12-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Hi. I've been looking at a bugzilla which describes a problem where a customer was advised to use either the "noac" or "actimeo=0" mount options to solve a consistency problem that they were seeing in the file attributes. It turned out that this solution did not work reliably for them because sometimes, the local attribute cache was believed to be valid and not timed out. (With an attribute cache timeout of 0, the cache should always appear to be timed out.) In looking at this situation, it appears to me that the problem is that the attribute cache timeout code has an off-by-one error in it. It is assuming that the cache is valid in the region, [read_cache_jiffies, read_cache_jiffies + attrtimeo]. The cache should be considered valid only in the region, [read_cache_jiffies, read_cache_jiffies + attrtimeo). With this change, the options, "noac" and "actimeo=0", work as originally expected. This problem was previously addressed by special casing the attrtimeo == 0 case. However, since the problem is only an off- by-one error, the cleaner solution is address the off-by-one error and thus, not require the special case. Thanx... ps Signed-off-by: Peter Staubach <staubach@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Use delegations to optimise ACCESS callsTrond Myklebust2008-12-231-1/+2
| | | | Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFSv4: Ensure that we set the verifier when revalidating delegated dentriesTrond Myklebust2008-12-231-2/+4
| | | | | | | This ensures that we don't have to look up the dentry again after we return the delegation if we know that the directory didn't change. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFSv4: Clean up is_atomic_open()Trond Myklebust2008-12-231-7/+8
| | | | Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* [PATCH] move executable checking into ->permission()Miklos Szeredi2008-10-231-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | For execute permission on a regular files we need to check if file has any execute bits at all, regardless of capabilites. This check is normally performed by generic_permission() but was also added to the case when the filesystem defines its own ->permission() method. In the latter case the filesystem should be responsible for performing this check. Move the check from inode_permission() inside filesystems which are not calling generic_permission(). Create a helper function execute_ok() that returns true if the inode is a directory or if any execute bits are present in i_mode. Also fix up the following code: - coda control file is never executable - sysctl files are never executable - hfs_permission seems broken on MAY_EXEC, remove - hfsplus_permission is eqivalent to generic_permission(), remove Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* [PATCH] make O_EXCL in nd->intent.flags visible in nd->flagsAl Viro2008-10-231-4/+2
| | | | | | | New flag: LOOKUP_EXCL. Set before doing the final step of pathname resolution on the paths that have LOOKUP_CREATE and O_EXCL. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vmscan: split LRU lists into anon & file setsRik van Riel2008-10-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Split the LRU lists in two, one set for pages that are backed by real file systems ("file") and one for pages that are backed by memory and swap ("anon"). The latter includes tmpfs. The advantage of doing this is that the VM will not have to scan over lots of anonymous pages (which we generally do not want to swap out), just to find the page cache pages that it should evict. This patch has the infrastructure and a basic policy to balance how much we scan the anon lists and how much we scan the file lists. The big policy changes are in separate patches. [lee.schermerhorn@hp.com: collect lru meminfo statistics from correct offset] [kosaki.motohiro@jp.fujitsu.com: prevent incorrect oom under split_lru] [kosaki.motohiro@jp.fujitsu.com: fix pagevec_move_tail() doesn't treat unevictable page] [hugh@veritas.com: memcg swapbacked pages active] [hugh@veritas.com: splitlru: BDI_CAP_SWAP_BACKED] [akpm@linux-foundation.org: fix /proc/vmstat units] [nishimura@mxp.nes.nec.co.jp: memcg: fix handling of shmem migration] [kosaki.motohiro@jp.fujitsu.com: adjust Quicklists field of /proc/meminfo] [kosaki.motohiro@jp.fujitsu.com: fix style issue of get_scan_ratio()] Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* NFS: Fix a resolution problem with nfs_inode->cache_change_attributeTrond Myklebust2008-10-141-1/+1
| | | | | | | | | | | The cache_change_attribute is used to decide whether or not a directory has changed, in which case we may need to look it up again. Again, the use of 'jiffies' leads to an issue of resolution. Once again, the fix is to change nfs_inode->cache_change_attribute, and just make it a simple counter. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Fix the resolution problem with nfs_inode_attrs_need_update()Trond Myklebust2008-10-141-4/+10
| | | | | | | | | | | | It appears that 'jiffies' timestamps do not have high enough resolution for nfs_inode_attrs_need_update(). One problem is that a GETATTR can be launched within < 1 jiffy of the last operation that updated the attribute. Another problem is that RPC calls can take < 1 jiffy to execute. We can fix this by switching the variables to use a simple global counter that gets incremented every time we start another GETATTR call. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Add options for finer control of the lookup cacheTrond Myklebust2008-10-071-0/+4
| | | | | | | | | | | | Add the flag NFS_MOUNT_LOOKUP_CACHE_NONEG to turn off the caching of negative dentries. In reality what we do is to force nfs_lookup_revalidate() to always discard negative dentries. Add the flag NFS_MOUNT_LOOKUP_CACHE_NONE for enforcing stricter revalidation of dentries. It forces the revalidate code to always do a lookup instead of just checking the cached mtime of the parent directory. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* [PATCH] sanitize ->permission() prototypeAl Viro2008-07-261-6/+5
| | | | | | | | | | | | | | | * kill nameidata * argument; map the 3 bits in ->flags anybody cares about to new MAY_... ones and pass with the mask. * kill redundant gfs2_iop_permission() * sanitize ecryptfs_permission() * fix remaining places where ->permission() instances might barf on new MAY_... found in mask. The obvious next target in that direction is permission(9) folded fix for nfs_permission() breakage from Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* NFS: Remove BKL from the readdir codeTrond Myklebust2008-07-151-3/+0
| | | | | | | Page accesses are serialised using the page locks, whereas all attribute updates are serialised using the inode->i_lock. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Remove BKL from the symlink codeTrond Myklebust2008-07-151-7/+1
| | | | | | | Page cache accesses are serialised using page locks, whereas attribute updates are serialised using inode->i_lock. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Remove BKL from the sillydelete operationsTrond Myklebust2008-07-151-6/+0
| | | | Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Remove the BKL from the rename, rmdir and unlink operationsTrond Myklebust2008-07-151-6/+3
| | | | | | | | Attribute updates are safe, and dentry operations are protected using VFS level locks. Defer removing the BKL from sillyrename until a separate patch. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Remove BKL from NFS lookup codeTrond Myklebust2008-07-151-8/+1
| | | | | | | | | | | | | All dentry-related operations are already BKL-safe, since they are protected by the VFS locking. No extra locks should be needed in the NFS code. In the case of nfs_revalidate_inode(), we're only doing an attribute update (protected by the inode->i_lock). In the case of nfs_lookup(), we're instantiating a new dentry, so there should be no contention possible until after we call d_materialise_unique. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Remove the BKL from nfs_link()Trond Myklebust2008-07-151-2/+0
| | | | Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Remove the BKL from the inode creation operationsTrond Myklebust2008-07-151-9/+0
| | | | | | | nfs_instantiate() does not require the BKL, neither do the attribute updates or the RPC code. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Remove BKL usage from open()Trond Myklebust2008-07-151-6/+0
| | | | | | | All the NFSv4 stateful operations are already protected by other locks (in particular by the rpc_sequence locks. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Remove the BKL from the permission checking codeTrond Myklebust2008-07-151-4/+0
| | | | Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Protect inode->i_nlink updates using inode->i_lockTrond Myklebust2008-07-151-2/+10
| | | | Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Use NFSDBG_FILE for all fopsChuck Lever2008-07-091-5/+5
| | | | | | | | | Clean up: some fops use NFSDBG_FILE, some use NFSDBG_VFS. Let's use NFSDBG_FILE for all fops, and consistently report file names instead of inode numbers. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Make nfs_open methods consistentChuck Lever2008-07-091-2/+5
| | | | | | | | Clean up: Report the same debugging info and count function calls the same for files and directories in nfs_opendir() and nfs_file_open(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Make nfs_llseek methods consistentChuck Lever2008-07-091-2/+10
| | | | | | | | Clean up: Report the same debugging info in nfs_llseek_dir() and nfs_llseek_file(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Make nfs_fsync methods consistentChuck Lever2008-07-091-1/+2
| | | | | | | | Clean up: Report the same debugging info, count function calls the same, and use similar function naming in nfs_fsync_dir() and nfs_fsync(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Fix readdir cache invalidationTrond Myklebust2008-07-081-1/+1
| | | | | | | | | | | | | | invalidate_inode_pages2_range() takes page offset arguments, not byte ranges. Another thought is that individual pages might perhaps get evicted by VM pressure, in which case we might perhaps want to re-read not only the evicted page, but all subsequent pages too (in case the server returns more/less data per page so that the alignment of the next entry changes). We should therefore remove the condition that we only do this on page->index==0. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* nfs: replace remaining __FUNCTION__ occurrencesHarvey Harrison2008-05-161-9/+9
| | | | | | | | | | __FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* Merge branch 'devel'Trond Myklebust2008-04-241-1/+1
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| * SUNRPC: Add a helper rpcauth_lookup_generic_cred()Trond Myklebust2008-03-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The NFSv4 protocol allows clients to negotiate security protocols on the fly in the case where an administrator on the server changes the export settings and/or in the case where we may have a filesystem migration event. Instead of having the NFS client code cache credentials that are tied to a particular AUTH method it is therefore preferable to have a generic credential that can be converted into whatever AUTH is in use by the RPC client when the read/write/sillyrename/... is put on the wire. We do this by means of the new "generic" credential, which basically just caches the minimal information that is needed to look up an RPCSEC_GSS, AUTH_SYS, or AUTH_NULL credential. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* | [PATCH] r/o bind mounts: check mnt instead of superblock directlyDave Hansen2008-04-191-1/+2
|/ | | | | | | | | | | | | | | | | | | If we depend on the inodes for writeability, we will not catch the r/o mounts when implemented. This patches uses __mnt_want_write(). It does not guarantee that the mount will stay writeable after the check. But, this is OK for one of the checks because it is just for a printk(). The other two are probably unnecessary and duplicate existing checks in the VFS. This won't make them better checks than before, but it will make them detect r/o mounts. Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* NFS: Fix dentry revalidation for NFSv4 referrals and mountpoint crossingsTrond Myklebust2008-03-071-0/+2
| | | | | | | | | | As long as the directory contents haven't changed, we should just let the path walk proceed to cross the mountpoint. Apart from being an optimisation in the case of 'nohide' mountpoint traversals, it also fixes an issue with referrals: referral inodes don't have valid filehandles, so calling nfs_revalidate_inode() on them is a bug. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>