Move this out of a local variable into the nfs4_delegation object in
preparation for making this an async rpc call (at which point we'll need
any state like this in a common object that's preserved across function
calls).
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

There's no point in keeping this field around--it's always zero.

(Background: the protocol allows you to tell the client that the file is
about to be truncated, as an optimization to save the client from
writing back dirty pages that will just be discarded.  We don't
implement this hint.  If we do some day, adding this field back in will
be the least of the work involved.)
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

The nfs4_cb_recall struct is used only in nfs4_delegation, so its
pointer to the containing delegation is unnecessary--we could just use
container_of().

But there's no real reason to have this a separate struct at all--just
move these fields to nfs4_delegation.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

I want to use the name for a struct that actually does represent a
single callback.

(Actually, I've never been sure it helps to a separate struct for the
callback information.  Some day maybe those fields could just be dumped
into struct nfs4_client.  I don't know.)
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

We don't really need a synchronous rpc, and moving to an asynchronous
rpc allows us to do without this extra kthread.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Lookup the callback cred once and then use it for all subsequent
callbacks.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

The code is a little simpler, and it should be easier to avoid races, if
we just do all rpc client creation/destruction from nfsd or laundromat
threads and do only the rpc calls themselves asynchronously.  The rpc
creation doesn't involve any significant waiting (it doesn't call the
client, for example), so there's no reason not to do this.

Also don't bother destroying the client on failure of the rpc null
probe.  We may want to retry the probe later anyway.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

This is just a minor code simplification.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

We tried to do something overly complicated with the callback rpc
timeouts here.  And they're wrong--the result is that by the time a
single callback times out, it's already too late to tell the client
(using the cb_path_down return to RENEW) that the callback is down.

Use a much shorter, simpler timeout.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

This setclientid_confirm case should allow the client to change
callbacks, but it currently has a dummy implementation that just turns
off callbacks completely.  That dummy implementation isn't completely
correct either, though:

	- There's no need to remove any client recovery directory in
	  this case.
	- New clientid confirm verifiers should be generated (and
	  returned) in setclientid; there's no need to generate a new
	  one here.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Stephen Rothwell said:
"Today's linux-next build (powerpc ppc64_defconfig) produced this new
warning:

fs/nfsd/nfs4state.c: In function 'EXPIRED_STATEID':
fs/nfsd/nfs4state.c:2757: warning: comparison of distinct pointer types lacks a cast

Caused by commit 78155ed7 ("nfsd4:
distinguish expired from stale stateids")."
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>

ext4 supports a real NFSv4 change attribute, which is bumped whenever
the ctime would be updated, including times when two updates arrive
within a jiffy of each other.  (Note that although ext4 has space for
nanosecond-precision ctime, the real resolution is lower: it actually
uses jiffies as the time-source.)  This ensures clients will invalidate
their caches when they need to.

There is some fear that keeping the i_version up-to-date could have
performance drawbacks, so for now it's turned on only by a mount option.
We hope to do something better eventually.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Theodore Tso <tytso@mit.edu>

We don't need comments to tell us these macros are ugly.  And we're long
past trying to share any of this code with the BSD's.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

This macro doesn't serve any useful purpose.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Clean up: For consistency, handle output buffer size checking in a
other nfsctl functions the same way it's done for write_versions().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

While it's not likely today that there are enough NFS versions to
overflow the output buffer in write_versions(), we should be more
careful about detecting the end of the buffer.

The number of NFS versions will only increase as NFSv4 minor versions
are added.

Note that this API doesn't behave the same as portlist.  Here we
attempt to display as many versions as will fit in the buffer, and do
not provide any indication that an overflow would have occurred.  I
don't have any good rationale for that.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

While it's not likely a pathname will be longer than
SIMPLE_TRANSACTION_SIZE, we should be more careful about just
plopping it into the output buffer without bounds checking.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Clean up svc_one_sock_name() by setting up automatic variables for
frequently used expressions.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Add an arm to the switch statement in svc_one_sock_name() so it can
construct the name of PF_INET6 sockets properly.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aime Le Rouzic <aime.le-rouzic@bull.net>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Use snprintf() in one_sock_name() to prevent overflowing the output
buffer.  If the name doesn't fit in the buffer, the buffer is filled
in with an empty string, and -ENAMETOOLONG is returned.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Adjust the synopsis of svc_sock_names() to pass in the size of the
output buffer.  Add a documenting comment.

This is a cosmetic change for now.  A subsequent patch will make sure
the buffer length is passed to one_sock_name(), where the length will
actually be useful.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Adjust the synopsis of svc_addsock() to pass in the size of the output
buffer.  Add a documenting comment.

This is a cosmetic change for now.  A subsequent patch will make sure
the buffer length is passed to one_sock_name(), where the length will
actually be useful.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

The svc_xprt_names() function can overflow its buffer if it's so near
the end of the passed in buffer that the "name too long" string still
doesn't fit.  Of course, it could never tell if it was near the end
of the passed in buffer, since its only caller passes in zero as the
buffer length.

Let's make this API a little safer.

Change svc_xprt_names() so it *always* checks for a buffer overflow,
and change its only caller to pass in the correct buffer length.

If svc_xprt_names() does overflow its buffer, it now fails with an
ENAMETOOLONG errno, instead of trying to write a message at the end
of the buffer.  I don't like this much, but I can't figure out a clean
way that's always safe to return some of the names, *and* an
indication that the buffer was not long enough.

The displayed error when doing a 'cat /proc/fs/nfsd/portlist' is
"File name too long".
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Clean up.

A couple of years ago, a series of commits, finishing with commit
5680c446, swapped the order of the lockd_up() and svc_addsock() calls
in __write_ports().  At that time lockd_up() needed to know the
transport protocol of the passed-in socket to start a listener on the
same transport protocol.

These days, lockd_up() doesn't take a protocol argument; it always
starts both a UDP and TCP listener.  It's now more straightforward to
try the lockd_up() first, then do a lockd_down() if the svc_addsock()
fails.

Careful review of this code shows that the svc_sock_names() call is
used only to close the just-opened socket in case lockd_up() fails.
So it is no longer needed if lockd_up() is done first.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Clean up: Refactor transport name listing out of __write_ports() to
make it easier to understand and maintain.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

User space must call listen(3) on SOCK_STREAM sockets passed into
/proc/fs/nfsd/portlist, otherwise that listener is ignored.  Document
this.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Clean up: Refactor the socket creation logic out of __write_ports() to
make it easier to understand and maintain.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Clean up: Refactor the socket closing logic out of __write_ports() to
make it easier to understand and maintain.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Clean up: Refactor transport addition out of __write_ports() to make
it easier to understand and maintain.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Clean up: Refactor transport removal out of __write_ports() to make it
easier to understand and maintain.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

The svc_addr_len() helper function returns -EAFNOSUPPORT if it doesn't
recognize the address family of the passed-in socket address.  However,
the return type of this function is size_t, which means -EAFNOSUPPORT
is turned into a very large positive value in this case.

The check in svc_udp_recvfrom() to see if the return value is less
than zero therefore won't work at all.

Additionally, handle_connect_req() passes this value directly to
memset().  This could cause memset() to clobber a large chunk of memory
if svc_addr_len() has returned an error.  Currently the address family
of these addresses, however, is known to be supported long before
handle_connect_req() is called, so this isn't a real risk.

Change the error return value of svc_addr_len() to zero, which fits in
the range of size_t, and is safer to pass to memset() directly.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Fix the following sparse warnings in net/sunrpc/svc_xprt.c.

  warning: symbol 'svc_recv' was not declared. Should it be static?
  warning: symbol 'svc_drop' was not declared. Should it be static?
  warning: symbol 'svc_send' was not declared. Should it be static?
  warning: symbol 'svc_close_all' was not declared. Should it be static?
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Cc: James Lentini <jlentini@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

If we encode the time of client creation into the stateid instead of the
time of server boot, then we can determine whether that stateid is from
a previous instance of the a server, or from a client that has expired,
and return an appropriate error to the client.
Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

For every lock request lockd creates a new file_lock object
in nlmsvc_setgrantargs() by copying the passed in file_lock with
locks_copy_lock(). A filesystem can attach it's own lock_operations
vector to the file_lock. It has to be cleaned up at the end of the
file_lock's life. However, lockd doesn't do it today, yet it
asserts in nlmclnt_release_lockargs() that the per-filesystem
state is clean.
This patch fixes it by exporting locks_release_private() and adding
it to nlmsvc_freegrantargs(), to be symmetrical to creating a
file_lock in nlmsvc_setgrantargs().
Signed-off-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

There is currently only one way for userspace to say "wait for my storage
device to get ready for the modules I just loaded": to load the
scsi_wait_scan module. Expectations of userspace are that once this
module is loaded, all the (storage) devices for which the drivers
were loaded before the module load are present.

Now, there are some issues with the implementation, and the async
stuff got caught in the middle of this: The existing code only
waits for the scsy async probing to finish, but it did not take
into account at all that probing might not have begun yet.
(Russell ran into this problem on his computer and the fix works for him)

This patch fixes this more thoroughly than the previous "fix", which
had some bad side effects (namely, for kernel code that wanted to wait for
the scsi scan it would also do an async sync, which would deadlock if you did
it from async context already.. there's a report about that on lkml):
The patch makes the module first wait for all device driver probes, and then it
will wait for the scsi parallel scan to finish.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Tested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix a comment typo in slow-work.h

...a trivial mistake, but it will mess up kerneldoc if nothing else.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Collect the DECLARE/DEFINE declarations together in linux/percpu-defs.h so
that they're in one place, and give them descriptive comments, particularly
the SHARED_ALIGNED variant.

It would be nice to collect these in linux/percpu.h, but that's not possible
without sorting out the severe #include recursion between the x86 arch headers
and the general headers (and possibly other arches too).
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>