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>
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>
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>
The error field in nfs_readdir_descriptor_t is never used outside of the
function in which it is set. Remove the field and change the place that
does use it to use an existing local variable.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Otherwise, there is a potential deadlock if the last dput() from an NFSv4
close() or other asynchronous operation leads to nfs_clear_inode calling
the synchronous delegreturn.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the server returns an ENOENT error, we still need to do a d_delete() in
order to ensure that the dentry is deleted.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Ensure that readdir revalidates its data cache after blocking on
sillyrename.
Also fix a typo in nfs_do_call_unlink(): swap the ^= for an |=. The result
is the same, since we've already checked that the flag is unset, but it
makes the code more readable.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Every file should include the headers containing the prototypes for its global
functions (in this case nfs_access_cache_shrinker()).
Signed-off-by: Adrian Bunk <bunk@kernel.org>
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>
lookup() and sillyrename() can race one another because the sillyrename()
completion cannot take the parent directory's inode->i_mutex since the
latter may be held by whoever is calling dput().
We therefore have little option but to add extra locking to ensure that
nfs_lookup() and nfs_atomic_open() do not race with the sillyrename
completion.
If somebody has looked up the sillyrenamed file in the meantime, we just
transfer the sillydelete information to the new dentry.
Please refer to the bug-report at
http://bugzilla.linux-nfs.org/show_bug.cgi?id=150
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This boot parameter will allow legacy 32-bit applications which call stat()
to continue to function even if the NFSv3/v4 server uses 64-bit inode
numbers.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
- NFS_READTIME, NFS_CHANGE_ATTR are completely unused.
- Inline the few remaining uses of NFS_ATTRTIMEO, and remove.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We don't need to call nfs_revalidate_inode() on the directory if we already
know that the verifiers don't match.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The lower level routines in fs/nfs/proc.c, fs/nfs/nfs3proc.c and
fs/nfs/nfs4proc.c should already be dealing with the revalidation issues.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The fact that we're in the process of modifying the inode does not mean
that we should not invalidate the attribute and data caches. The defensive
thing is to always invalidate when we're confronted with inode
mtime/ctime or change_attribute updates that we do not immediately
recognise.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the ->lookup() call causes the directory verifier to change, then there
is still no need to use the old verifier, since our dentry has been
verified.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We don't want to leave an unverified hashed negative dentry if the
exclusive create fails to complete.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
That will also allow us to remove the calls in mknod and mkdir.
In addition it will ensure that symlinks set it correctly.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We don't care about whether or not some other process on our client is
changing the directory while we're in nfs_lookup_revalidate(), because the
dcache will take care of ensuring local atomicity.
We can therefore remove the test for nfs_caches_unstable().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFSv3 will correctly update atime on a readdir call, so there is no need to
set the NFS_INO_INVALID_ATIME flag unless the call to nfs_refresh_inode()
fails.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We don't need to force a dentry lookup just because we're making changes to
the directory.
Don't update nfsi->cache_change_attribute in nfs_end_data_update: that
overrides the NFSv3/v4 weak consistency checking that tells us our update
was the only one, and that tells us the dcache is still valid.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, _nfs4_do_access() is just a copy of nfs_do_access() with added
conversion of the open flags into an access mask. This patch merges the
duplicate functionality.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
nfs_set_verifier() and nfs_refresh_verifier() do exactly the same thing, so
replace one with the other.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The nfs_renew_times() function plants the current time in jiffies in
dentry->d_time. But a call to nfs_renew_times() is always followed by
another call that overwrites dentry->d_time. Get rid of the
nfs_renew_times() calls.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Negative dentries need to be reverified after an asynchronous unlink.
Quoth Trond:
"Unfortunately I don't think that we can avoid revalidating the
resulting negative dentry since the UNLINK call is asynchronous,
and so the new verifier on the directory will only be known a
posteriori."
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
I would like to discuss the idea that the current checks for attribute
timeout using time_after are inadequate for 32bit architectures, since
time_after works correctly only when the two timestamps being compared
are within 2^31 jiffies of each other. The signed overflow caused by
comparing values more than 2^31 jiffies apart will flip the result,
causing incorrect assumptions of validity.
2^31 jiffies is a fairly large period of time (~25 days) when compared
to the lifetime of most kernel data structures, but for long lived NFS
mounts that can sit idle for months (think that for some reason autofs
cannot be used), it is easy to compare inode attribute timestamps with
very disparate or even bogus values (as in when jiffies have wrapped
many times, where the comparison doesn't even make sense).
Currently the code tests for attribute timeout by simply adding the
desired amount of jiffies to the stored timestamp and comparing that
with the current timestamp of obtained attribute data with time_after.
This is incorrect, as it returns true for the desired timeout period
and another full 2^31 range of jiffies.
In testing with artificial jumps (several small jumps, not one big
crank) of the jiffies I was able to reproduce a problem found in a
server with very long lived NFS mounts, where attributes would not be
refreshed even after touching files and directories in the server:
Initial uptime:
03:42:01 up 6 min, 0 users, load average: 0.01, 0.12, 0.07
NFS volume is mounted and time is advanced:
03:38:09 up 25 days, 2 min, 0 users, load average: 1.22, 1.05, 1.08
# ls -l /local/A/foo/bar /nfs/A/foo/bar
-rw-r--r-- 1 root root 0 Dec 17 03:38 /local/A/foo/bar
-rw-r--r-- 1 root root 0 Nov 22 00:36 /nfs/A/foo/bar
# touch /local/A/foo/bar
# ls -l /local/A/foo/bar /nfs/A/foo/bar
-rw-r--r-- 1 root root 0 Dec 17 03:47 /local/A/foo/bar
-rw-r--r-- 1 root root 0 Nov 22 00:36 /nfs/A/foo/bar
We can see the local mtime is updated, but the NFS mount still shows
the old value. The patch below makes it work:
Initial setup...
07:11:02 up 25 days, 1 min, 0 users, load average: 0.15, 0.03, 0.04
# ls -l /local/A/foo/bar /nfs/A/foo/bar
-rw-r--r-- 1 root root 0 Jan 11 07:11 /local/A/foo/bar
-rw-r--r-- 1 root root 0 Jan 11 07:11 /nfs/A/foo/bar
# touch /local/A/foo/bar
# ls -l /local/A/foo/bar /nfs/A/foo/bar
-rw-r--r-- 1 root root 0 Jan 11 07:14 /local/A/foo/bar
-rw-r--r-- 1 root root 0 Jan 11 07:14 /nfs/A/foo/bar
Signed-off-by: Fabio Olive Leite <fleite@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Hi.
Attached is a patch to modify the NFS client code to support
64 bit ino's, as appropriate for the system and the NFS
protocol version.
The code basically just expand the NFS interfaces for routines
which handle ino's from using ino_t to u64 and then uses the
fileid in the nfs_inode instead of i_ino in the inode. The
code paths that were updated are in the getattr method and
the readdir methods.
This should be no real change on 64 bit platforms. Since
the ino_t is an unsigned long, it would already be 64 bits
wide.
Thanx...
ps
Signed-off-by: Peter Staubach <staubach@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It doesn't look as if the NFS file name limit is being initialised correctly
in the struct nfs_server. Make sure that we limit whatever is being set in
nfs_probe_fsinfo() and nfs_init_server().
Also ensure that readdirplus and nfs4_path_walk respect our file name
limits.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix a couple of bugs:
- Don't rely on the parent dentry still being valid when the call completes.
Fixes a race with shrink_dcache_for_umount_subtree()
- Don't remove the file if the filehandle has been labelled as stale.
Fix a couple of inefficiencies
- Remove the global list of sillyrenamed files. Instead we can cache the
sillyrename information in the dentry->d_fsdata
- Move common code from unlink_setup/unlink_done into fs/nfs/unlink.c
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
nfs_symlink() allocates a GFP_KERNEL page for the pagecache. Most
pagecache pages are allocated using GFP_HIGHUSER, and there's no reason
not to do that in nfs_symlink() as well.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
