This patch adds readdir plus support to the cache array.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If we're going through the loop in nfs_readdir() more than once, we usually
do not want to restart searching from the beginning of the pages cache.
We only want to do that if the previous search failed...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This patch adds the readdir cache array and functions to retreive the array
stored on a cache page, clear the array by freeing allocated memory, add an
entry to the array, and search the array for a given cookie.
It then modifies readdir to make use of the new cache array.
With the new cache array method, we no longer need some of this code.
Finally, nfs_llseek_dir() will set file->f_pos to a value greater than 0 and
desc->dir_cookie to zero. When we see this, readdir needs to find the file
at position file->f_pos from the start of the directory.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If nfs_intent_set_file() returns an error, we usually want to pass that
back up the stack.
Also ensure that nfs_open_revalidate() returns '1' on success.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
...since that's where most of the sillyrenaming code lives. A comment
block is added to the beginning as well to clarify how sillyrenaming
works. Also, make nfs_async_unlink static as nfs_sillyrename is the only
caller.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Remove all remaining references to the struct nameidata from the low level
NFS layers. Again pass down a partially initialised struct nfs_open_context
when we want to do atomic open+create.
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>
To obey NFS cache semantics, the client must verify the cached
attributes when a file is opened. In most cases this is done by a call to
d_validate as one of the last steps in path_walk.
However for the root of a filesystem, d_validate is only ever called
on the mounted-on filesystem (except when the path ends '.' or '..').
So NFS has no chance to validate the attributes.
So, in nfs_opendir, we revalidate the attributes if the opened
directory is the mountpoint. This may cause double-validation for "."
and ".." lookups, but that is better than missing regular /path/name
lookups completely.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* 'nfs-for-2.6.36' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (42 commits)
NFS: NFSv4.1 is no longer a "developer only" feature
NFS: NFS_V4 is no longer an EXPERIMENTAL feature
NFS: Fix /proc/mount for legacy binary interface
NFS: Fix the locking in nfs4_callback_getattr
SUNRPC: Defer deleting the security context until gss_do_free_ctx()
SUNRPC: prevent task_cleanup running on freed xprt
SUNRPC: Reduce asynchronous RPC task stack usage
SUNRPC: Move the bound cred to struct rpc_rqst
SUNRPC: Clean up of rpc_bindcred()
SUNRPC: Move remaining RPC client related task initialisation into clnt.c
SUNRPC: Ensure that rpc_exit() always wakes up a sleeping task
SUNRPC: Make the credential cache hashtable size configurable
SUNRPC: Store the hashtable size in struct rpc_cred_cache
NFS: Ensure the AUTH_UNIX credcache is allocated dynamically
NFS: Fix the NFS users of rpc_restart_call()
SUNRPC: The function rpc_restart_call() should return success/failure
NFSv4: Get rid of the bogus RPC_ASSASSINATED(task) checks
NFSv4: Clean up the process of renewing the NFSv4 lease
NFSv4.1: Handle NFS4ERR_DELAY on SEQUENCE correctly
NFS: nfs_rename() should not have to flush out writebacks
...
We don't really support nfs servers that invalidate the file handle after a
rename, so precautions such as flushing out dirty data before renaming the
file are superfluous.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently MAY_ACCESS means that filesystems must check the permissions
right then and not rely on cached results or the results of future
operations on the object. This can be because of a call to sys_access() or
because of a call to chdir() which needs to check search without relying on
any future operations inside that dir. I plan to use MAY_ACCESS for other
purposes in the security system, so I split the MAY_ACCESS and the
MAY_CHDIR cases.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
The current shrinker implementation requires the registered callback
to have global state to work from. This makes it difficult to shrink
caches that are not global (e.g. per-filesystem caches). Pass the shrinker
structure to the callback so that users can embed the shrinker structure
in the context the shrinker needs to operate on and get back to it in the
callback via container_of().
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Commit 9c7e7e2337 (NFS: Don't call iput() in
nfs_access_cache_shrinker) unintentionally removed the spin unlock for the
inode->i_lock.
Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
iput() can potentially attempt to allocate memory, so we should avoid
calling it in a memory shrinker. Instead, rely on the fact that iput() will
call nfs_access_zap_cache().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Both iput() and put_rpccred() might allocate memory under certain
circumstances, so make sure that we don't recurse and deadlock...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* '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
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>
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
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>
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>
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>
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>
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>
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>
* 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>
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>
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>
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=12557https://bugs.launchpad.net/ubuntu/+source/linux/+bug/269954http://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>
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>
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>
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>
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>
Bryan Schumaker