We want to use the nfsd4_compound_state to cache the nfs4_client in
order to optimise away extra lookups of the clid.

In the v4.0 case, we use this to ensure that we only have to look up the
client at most once per compound for each call into lookup_clientid. For
v4.1+ we set the pointer in the cstate during SEQUENCE processing so we
should never need to do a search for it.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

I saw this pop up with some pynfs testing:

    [  123.609992] nfsd: non-standard errno: -7

...and -7 is -E2BIG. I think what happened is that XFS returned -E2BIG
due to some xattr operations with the ACL10 pynfs TEST (I guess it has
limited xattr size?).

Add a better mapping for that error since it's possible that we'll need
it. How about we convert it to NFSERR_FBIG? As Bruce points out, they
both have "BIG" in the name so it must be good.

Also, turn the printk in this function into a WARN() so that we can get
a bit more information about situations that don't have proper mappings.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Commit 2a7420c03e504 (nfsd: Ensure that nfsd_create_setattr commits
files to stable storage), added a couple of calls to commit_metadata,
but doesn't convert their return codes to __be32 in the appropriate
places.

Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The cstate already holds information about the session, and hence
the client id, so it makes more sense to pass that information
rather than the current practice of passing a 'minor version' number.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

If the client were to disappear from underneath us while we're holding
a session reference, things would be bad. This cleanup helps ensure
that it cannot, which will be a possibility when the client_mutex is
removed.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Now that we know that we won't have several lockowners with the same,
owner->data, we can simplify nfsd4_release_lockowner and get rid of
the lo_list in the process.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Just like open-owners, lock-owners are associated with a name, a clientid
and, in the case of minor version 0, a sequence id. There is no association
to a file.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

A lockowner can have more than one lock stateid. For instance, if a
process has more than one file open and has locks on both, then the same
lockowner has more than one stateid associated with it. Change it so
that this reality is better reflected by the objects that nfsd uses.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

In the NFSv4 spec, lock stateids are per-file objects. Lockowners are not.
This patch replaces the current list of lock owners in the open stateids
with a list of lock stateids.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Minor cleanup that should introduce no behavioral changes.

Currently this function just unhashes the stateid and leaves the caller
to do the work of the CLOSE processing.

Change nfsd4_close_open_stateid so that it handles doing all of the work
of closing a stateid. Move the handling of the unhashed stateid into it
instead of doing that work in nfsd4_close. This will help isolate some
coming changes to stateid handling from nfsd4_close.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

There's no need to confirm an openowner in v4.1 and above, so we can
go ahead and set NFS4_OO_CONFIRMED when we create openowners in
those versions. This will also be necessary when we remove the
client_mutex, as it'll be possible for two concurrent opens to race
in versions >4.0.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Move the slot return, put session etc into a helper in fs/nfsd/nfs4state.c
instead of open coding in nfs4svc_encode_compoundres.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Not technically a bugfix, since nothing tries to use the return pointer
if this function doesn't return success, but it could be a problem
with some coming changes.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Currently, the maximum number of connections that nfsd will allow
is based on the number of threads spawned. While this is fine for a
default, there really isn't a clear relationship between the two.

The number of threads corresponds to the number of concurrent requests
that we want to allow the server to process at any given time. The
connection limit corresponds to the maximum number of clients that we
want to allow the server to handle. These are two entirely different
quantities.

Break the dependency on increasing threads in order to allow for more
connections, by adding a new per-net parameter that can be set to a
non-zero value. The default is still to base it on the number of threads,
so there should be no behavior change for anyone who doesn't use it.

Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Since nfsd_create_setattr strips the mode from the struct iattr, it
is quite possible that it will optimise away the call to nfsd_setattr
altogether.
If this is the case, then we never call commit_metadata() on the
newly created file.

Also ensure that both nfsd_setattr() and nfsd_create_setattr() fail
when the call to commit_metadata fails.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Commit db2e747b (vfs: remove mode parameter from vfs_symlink())
have remove mode parameter from vfs_symlink.
So that, iattr isn't needed by nfsd_symlink now, just remove it.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Current code depends on the client_mutex to guarantee a single struct
nfs4_file per inode in the file_hashtbl and make addition atomic with
respect to lookup.  Rely instead on the state_Lock, to make it easier to
stop taking the client_mutex here later.

To prevent an i_lock/state_lock inversion, change nfsd4_init_file to
use ihold instead if igrab. That's also more efficient anyway as we
definitely hold a reference to the inode at that point.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

nfsd4_process_open2 will currently will get access to the file, and then
call nfsd4_truncate to (possibly) truncate it. If that operation fails
though, then the access references will never be released as the
nfs4_ol_stateid is never initialized.

Fix by moving the nfsd4_truncate call into nfs4_get_vfs_file, ensuring
that the refcounts are properly put if the truncate fails.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

fs/nfsd/nfs4xdr.c: In function 'nfsd4_encode_readv':
>> fs/nfsd/nfs4xdr.c:3137:148: warning: comparison of distinct pointer types lacks a cast [enabled by default]
thislen = min(len, ((void *)xdr->end - (void *)xdr->p));
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Avoid an extra allocation for the tmpbuf struct itself, and stop
ignoring some allocation failures.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

This is a not-that-useful kmalloc wrapper.  And I'd like one of the
callers to actually use something other than kmalloc.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

28e05dd8 "knfsd: nfsd4: represent nfsv4 acl with array instead of
linked list" removed the last user that wanted a custom free function.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The name of a link is currently stored in cr_name and cr_namelen, and
the content in cr_linkname and cr_linklen.  That's confusing.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Currently nfsd_symlink has a weird hack to serve callers who don't
null-terminate symlink data: it looks ahead at the next byte to see if
it's zero, and copies it to a new buffer to null-terminate if not.

That means callers don't have to null-terminate, but they *do* have to
ensure that the byte following the end of the data is theirs to read.

That's a bit subtle, and the NFSv4 code actually got this wrong.

So let's just throw out that code and let callers pass null-terminated
strings; we've already fixed them to do that.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

It's simple enough for NFSv2 to null-terminate the symlink data.

A bit weird (it depends on knowing that we've already read the following
byte, which is either padding or part of the mode), but no worse than
the conditional kstrdup it otherwise relies on in nfsd_symlink().
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

An NFS operation that creates a new symlink includes the symlink data,
which is xdr-encoded as a length followed by the data plus 0 to 3 bytes
of zero-padding as required to reach a 4-byte boundary.

The vfs, on the other hand, wants null-terminated data.

The simple way to handle this would be by copying the data into a newly
allocated buffer with space for the final null.

The current nfsd_symlink code tries to be more clever by skipping that
step in the (likely) case where the byte following the string is already
0.

But that assumes that the byte following the string is ours to look at.
In fact, it might be the first byte of a page that we can't read, or of
some object that another task might modify.

Worse, the NFSv4 code tries to fix the problem by actually writing to
that byte.

In the NFSv2/v3 cases this actually appears to be safe:

	- nfs3svc_decode_symlinkargs explicitly null-terminates the data
	  (after first checking its length and copying it to a new
	  page).
	- NFSv2 limits symlinks to 1k.  The buffer holding the rpc
	  request is always at least a page, and the link data (and
	  previous fields) have maximum lengths that prevent the request
	  from reaching the end of a page.

In the NFSv4 case the CREATE op is potentially just one part of a long
compound so can end up on the end of a page if you're unlucky.

The minimal fix here is to copy and null-terminate in the NFSv4 case.
The nfsd_symlink() interface here seems too fragile, though.  It should
really either do the copy itself every time or just require a
null-terminated string.
Reported-by: Jeff Layton <jlayton@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Currently rpc_pton() fails to handle the case where you echo an address
into the file, as it barfs on the newline. Ensure that we NULL out the
first occurrence of any newline.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

AFAICT, the only way to hit this error is to pass this function a bogus
"who" value. In that case, we probably don't want to return -1 as that
could get sent back to the client. Turn this into nfserr_serverfault,
which is a more appropriate error for a server bug like this.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The filehandle structs all use host-endian values, but will sometimes
stuff big-endian values into those fields. This is OK since these
values are opaque to the client, but it confuses sparse. Add __force to
make it clear that we are doing this intentionally.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The callers expect a __be32 return and the functions they call return
__be32, so having these return int is just wrong. Also, nfsd_finish_read
can be made static.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

We currently hash the XID to determine a hash bucket to use for the
reply cache entry, which is fed into hash_32 without byte-swapping it.
Add __force to make sparse happy, and add some comments to explain
why.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

sparse complains that we're stuffing non-byte-swapped values into
__be32's here. Since they're supposed to be opaque, it doesn't matter
much. Just add __force to make sparse happy.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Don't using cache_get besides export.h, using exp_get for export.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

rq_usedeferral and rq_splice_ok are used as 0 and 1, just defined to bool.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Pull i2c new drivers from Wolfram Sang:
 "Here is a pull request from i2c hoping for the "new driver" rule.

  Originally, I wanted to send this request during the merge window, but
  code checkers with very recent additions complained, so a few fixups
  were needed.  So, some more time went by and I merged rc1 to get a
  stable base"

So the "new driver" rule is really about drivers that people absolutely
need for the kernel to work on new hardware, which is not so much the
case for i2c.  So I considered not pulling this, but eventually
relented.

Just for FYI: the whole (and only) point of "new drivers" is not that
new drivers cannot regress things (they can, and they have - by
triggering badly tested code on machines that never triggered that code
before), but because they can bring to life machines that otherwise
wouldn't be useful at all without the drivers.

So the new driver rule is for essential things that actual consumers
would care about, ie devices like networking or disk drivers that matter
to normal people (not server people - they run old kernels anyway, so
mainlining new drivers is irrelevant for them).

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: sun6-p2wi: fix call to snprintf
  i2c: rk3x: add NULL entry to the end of_device_id array
  i2c: sun6i-p2wi: use proper return value in probe
  i2c: sunxi: add P2WI (Push/Pull 2 Wire Interface) controller support
  i2c: sunxi: add P2WI DT bindings documentation
  i2c: rk3x: add driver for Rockchip RK3xxx SoC I2C adapter

Pull file locking fixes from Jeff Layton:
 "File locking related bugfixes

  Nothing too earth-shattering here.  A fix for a potential regression
  due to a patch in pile #1, and the addition of a memory barrier to
  prevent a race condition between break_deleg and generic_add_lease"

* tag 'locks-v3.16-2' of git://git.samba.org/jlayton/linux:
  locks: set fl_owner for leases back to current->files
  locks: add missing memory barrier in break_deleg