This patch addresses a compatibility issue with a Linux NFS server and
AIX NFS client.

I have exported /export as fsid=0 with sec=krb5:krb5i
I have mount --bind /home onto /export/home
I have exported /export/home with sec=krb5i

The AIX client mounts / -o sec=krb5:krb5i onto /mnt

If I do an ls /mnt, the AIX client gets a permission error. Looking at
the network traceIwe see a READDIR looking for attributes
FATTR4_RDATTR_ERROR and FATTR4_MOUNTED_ON_FILEID. The response gives a
NFS4ERR_WRONGSEC which the AIX client is not expecting.

Since the AIX client is only asking for an attribute that is an
attribute of the parent file system (pseudo root in my example), it
seems reasonable that there should not be an error.

In discussing this issue with Bruce Fields, I initially proposed
ignoring the error in nfsd4_encode_dirent_fattr() if all that was being
asked for was FATTR4_RDATTR_ERROR and FATTR4_MOUNTED_ON_FILEID, however,
Bruce suggested that we avoid calling cross_mnt() if only these
attributes are requested.

The following patch implements bypassing cross_mnt() if only
FATTR4_RDATTR_ERROR and FATTR4_MOUNTED_ON_FILEID are called. Since there
is some complexity in the code in nfsd4_encode_fattr(), I didn't want to
duplicate code (and introduce a maintenance nightmare), so I added a
parameter to nfsd4_encode_fattr() that indicates whether it should
ignore cross mounts and simply fill in the attribute using the passed in
dentry as opposed to it's parent.
Signed-off-by: NFrank Filz <ffilzlnx@us.ibm.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

This header is used only in a few places in fs/nfsd, so there seems to
be little point to having it in include/.  (Thanks to Robert Day for
pointing this out.)

Cc: Robert P. J. Day <rpjday@crashcourse.ca>
Acked-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Newer server features such as nfsv4 and gss depend on proc to work, so a
failure to initialize the proc files they need should be treated as
fatal.

Thanks to Andrew Morton for style fix and compile fix in case where
CONFIG_NFSD_V4 is undefined.

Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

If the reply cache initialization fails due to a kmalloc failure,
currently we try to soldier on with a reduced (or nonexistant) reply
cache.

Better to just fail immediately: the failure is then much easier to
understand and debug, and it could save us complexity in some later
code.  (But actually, it doesn't help currently because the cache is
also turned off in some odd failure cases; we should probably find a
better way to handle those failure cases some day.)

Fix some minor style problems while we're at it, and rename
nfsd_cache_init() to remove the need for a comment describing it.
Acked-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Clean up: For consistency, store the length of path name strings in nfsd
argument structures as unsigned integers.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Acked-By: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Clean up: adjust the sign of the length argument of nfsd_lookup and
nfsd_lookup_dentry, for consistency with recent changes.  NFSD version
4 callers already pass an unsigned file name length.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Acked-By: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Clean up: For consistency, store the length of file name strings in nfsd
argument structures as unsigned integers.  This matches the XDR routines
and client argument structures for the same operation types.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Acked-By: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

This patch makes the following needlessly global functions static:
- exp_get_by_name()
- exp_parent()
- exp_find()
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Cc: Neil Brown <neilb@suse.de>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Modify the NFS server code to support 64 bit ino's, as
appropriate for the system and the NFS protocol version.

The gist of the changes is to query the underlying file system
for attributes and not just to use the cached attributes in the
inode.  For this specific purpose, the inode only contains an
ino field which unsigned long, which is large enough on 64 bit
platforms, but is not large enough on 32 bit platforms.

I haven't been able to find any reason why ->getattr can't be called
while i_mutex.  The specification indicates that i_mutex is not
required to be held in order to invoke ->getattr, but it doesn't say
that i_mutex can't be held while invoking ->getattr.

I also haven't come to any conclusions regarding the value of
lease_get_mtime() and whether it should or should not be invoked
by fill_post_wcc() too.  I chose not to change this because I
thought that it was safer to leave well enough alone.  If we
decide to make a change, it can be done separately.
Signed-off-by: NPeter Staubach <staubach@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Acked-by: NNeil Brown <neilb@suse.de>

We have some slabs that the nfs4 server uses to store state objects.
We're currently creating and destroying those slabs whenever the server
is brought up or down.  That seems excessive; may as well just do that
in module initialization and exit.

Also add some minor header cleanup.  (Thanks to Andrew Morton for that
and a compile fix.)
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Acked-by: NNeil Brown <neilb@suse.de>

Share a little common code, reverse the arguments for consistency, drop the
unnecessary "inline", and lowercase the name.
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

EX_RDONLY is only called in one place; just put it there.
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Allow root squashing to vary per-pseudoflavor, so that you can (for example)
allow root access only when sufficiently strong security is in use.
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Implement the secinfo operation.

(Thanks to Usha Ketineni wrote an earlier version of this support.)

Cc: Usha Ketineni <uketinen@us.ibm.com>
Signed-off-by: NAndy Adamson <andros@citi.umich.edu>
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Allow readonly access to vary depending on the pseudoflavor, using the flag
passed with each pseudoflavor in the export downcall.  The rest of the flags
are ignored for now, though some day we might also allow id squashing to vary
based on the flavor.
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make the first actual use of the secinfo information by using it to return
nfserr_wrongsec when an export is found that doesn't allow the flavor used on
this request.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NAndy Adamson <andros@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Split the callers of exp_get_by_name(), exp_find(), and exp_parent() into
those that are processing requests and those that are doing other stuff (like
looking up filehandles for mountd).

No change in behavior, just a (fairly pointless, on its own) cleanup.

(Note this has the effect of making nfsd_cross_mnt() pass rqstp->rq_client
instead of exp->ex_client into exp_find_by_name().  However, the two should
have the same value at this point.)
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We're passing three arguments to exp_pseudoroot, two of which are just fields
of the svc_rqst.  Soon we'll want to pass in a third field as well.  So let's
just give up and pass in the whole struct svc_rqst.

Also sneak in some minor style cleanups while we're at it.
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We add a list of pseudoflavors to each export downcall, which will be used
both as a list of security flavors allowed on that export, and (in the order
given) as the list of pseudoflavors to return on secinfo calls.

This patch parses the new downcall information and adds it to the export
structure, but doesn't use it for anything yet.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NAndy Adamson <andros@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

One more incremental delegation policy improvement: don't give out a
delegation on a file if conflicting access has previously required that a
delegation be revoked on that file.  (In practice we'll forget about the
conflict when the struct nfs4_file is removed on close, so this is of limited
use for now, though it should at least solve a temporary problem with
self-conflicts on write opens from the same client.)
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Our original NFSv4 delegation policy was to give out a read delegation on any
open when it was possible to.

Since the lifetime of a delegation isn't limited to that of an open, a client
may quite reasonably hang on to a delegation as long as it has the inode
cached.  This becomes an obvious problem the first time a client's inode cache
approaches the size of the server's total memory.

Our first quick solution was to add a hard-coded limit.  This patch makes a
mild incremental improvement by varying that limit according to the server's
total memory size, allowing at most 4 delegations per megabyte of RAM.

My quick back-of-the-envelope calculation finds that in the worst case (where
every delegation is for a different inode), a delegation could take about
1.5K, which would make the worst case usage about 6% of memory.  The new limit
works out to be about the same as the old on a 1-gig server.

[akpm@linux-foundation.org: Don't needlessly bloat vmlinux]
[akpm@linux-foundation.org: Make it right for highmem machines]
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It looks like Al Viro gutted this header file five years ago and it hasn't
been touched since.
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

NFS4_FHSIZE is measured in bytes, not 4-byte words, so much more space than
necessary is being allocated for struct nfs4_cb_recall.

I should have wondered why this structure was so much larger than it needed to
be!
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add support for using a filesystem UUID to identify and export point in the
filehandle.

For NFSv2, this UUID is xor-ed down to 4 or 8 bytes so that it doesn't take up
too much room.  For NFSv3+, we use the full 16 bytes, and possibly also a
64bit inode number for exports beneath the root of a filesystem.

When generating an fsid to return in 'stat' information, use the UUID (hashed
down to size) if it is available and a small 'fsid' was not specifically
provided.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

NFS_SUPER_MAGIC is already defined in include/linux/magic.h
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

nfsd defines a type 'encode_dent_fn' which is much like 'filldir_t' except
that the first pointer is 'struct readdir_cd *' rather than 'void *'.  It
then casts encode_dent_fn points to 'filldir_t' as needed.  This hides any
other type mismatches between the two such as the fact that the 'ino' arg
recently changed from ino_t to u64.

So: get rid of 'encode_dent_fn', get rid of the cast of the function type,
change the first arg of various functions from 'struct readdir_cd *' to
'void *', and live with the fact that we have a little less type checking
on the calling of these functions now.  Less internal (to nfsd) checking
offset by more external checking, which is more important.

Thanks to Gabriel Paubert <paubert@iram.es> for discovering this and
providing an initial patch.
Signed-off-by: NGabriel Paubert <paubert@iram.es>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A couple of the warnings will be followed by an Oops if they ever fire, so may
as well be BUG_ON.  Another isn't obviously fatal but has never been known to
fire, so make it a WARN_ON.

Cc: Adrian Bunk <bunk@stusta.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Define an op descriptor struct, use it to simplify nfsd4_proc_compound().
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Tuck away the replay_owner in the cstate while we're at it.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Pass the saved and current filehandles together into all the nfsd4 compound
operations.

I want a unified interface to these operations so we can just call them by
pointer and throw out the huge switch statement.

Also I'll eventually want a structure like this--that holds the state used
during compound processing--for deferral.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

A comment here incorrectly states that "slack_space" is measured in words, not
bytes.  Remove the comment, and adjust a variable name and a few comments to
clarify the situation.

This is pure cleanup; there should be no change in functionality.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

In the case where an open creates the file, we shouldn't be rechecking
permissions to open the file; the open succeeds regardless of what the new
file's mode bits say.

This patch fixes the problem, but only by introducing yet another parameter
to nfsd_create_v3.  This is ugly.  This will be fixed by later patches.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Acked-by: NNeil Brown <neilb@suse.de>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We are using NFS_REPLAY_ME as a special error value that is never leaked to
clients.  That works fine; the only problem is mixing host- and network-
endian values in the same objects.  Network-endian equivalent would work just
as fine; switch to it.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

don't use the same variable to store NFS and host error values
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>