Commit Graph

1852 Commits

Author SHA1 Message Date
Eric W. Biederman
f025adf191 sunrpc: Properly decode kuids and kgids in RPC_AUTH_UNIX credentials
When reading kuids from the wire map them into the initial user
namespace, and validate the mapping succeded.

When reading kgids from the wire map them into the initial user
namespace, and validate the mapping succeded.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:15:26 -08:00
Eric W. Biederman
25da926371 sunrpc: Properly encode kuids and kgids in auth.unix.gid rpc pipe upcalls.
When a new rpc connection is established with an in-kernel server, the
traffic passes through svc_process_common, and svc_set_client and down
into svcauth_unix_set_client if it is of type RPC_AUTH_NULL or
RPC_AUTH_UNIX.

svcauth_unix_set_client then looks at the uid of the credential we
have assigned to the incomming client and if we don't have the groups
already cached makes an upcall to get a list of groups that the client
can use.

The upcall encodes send a rpc message to user space encoding the uid
of the user whose groups we want to know.  Encode the kuid of the user
in the initial user namespace as nfs mounts can only happen today in
the initial user namespace.

When a reply to an upcall comes in convert interpret the uid and gid values
from the rpc pipe as uids and gids in the initial user namespace and convert
them into kuids and kgids before processing them further.

When reading proc files listing the uid to gid list cache convert the
kuids and kgids from into uids and gids the initial user namespace.  As we are
displaying server internal details it makes sense to display these values
from the servers perspective.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:15:25 -08:00
Eric W. Biederman
a570abbb96 sunrpc: Properly encode kuids and kgids in RPC_AUTH_UNIX credentials
When writing kuids onto the wire first map them into the initial user
namespace.

When writing kgids onto the wire first map them into the initial user
namespace.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:15:24 -08:00
Eric W. Biederman
9e469e30d7 sunrpc: Hash uids by first computing their value in the initial userns
In svcauth_unix introduce a helper unix_gid_hash as otherwise the
expresion to generate the hash value is just too long.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:15:23 -08:00
Eric W. Biederman
683428fae8 sunrpc: Update svcgss xdr handle to rpsec_contect cache
For each received uid call make_kuid and validate the result.
For each received gid call make_kgid and validate the result.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:15:22 -08:00
Eric W. Biederman
90602c7b19 sunrpc: Update gss uid to security context mapping.
- Use from_kuid when generating the on the wire uid values.
- Use make_kuid when reading on the wire values.

In gss_encode_v0_msg, since the uid in gss_upcall_msg is now a kuid_t
generate the necessary uid_t value on the stack copy it into
gss_msg->databuf where it can safely live until the message is no
longer needed.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:15:21 -08:00
Eric W. Biederman
e572fc7398 sunrpc: Use gid_valid to test for gid != INVALID_GID
In auth unix there are a couple of places INVALID_GID is used a
sentinel to mark the end of uc_gids array.  Use gid_valid
as a type safe way to verify we have not hit the end of
valid data in the array.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:15:20 -08:00
Eric W. Biederman
cdba321e29 sunrpc: Convert kuids and kgids to uids and gids for printing
When printing kuids and kgids for debugging purpropses convert them
to ordinary integers so their values can be fed to the oridnary
print functions.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:15:19 -08:00
Eric W. Biederman
9132adb021 sunrpc: Simplify auth_unix now that everything is a kgid_t
In unx_create_cred directly assign gids from acred->group_info
to cred->uc_gids.

In unx_match directly compare uc_gids with group_info.

Now that both group_info and unx_cred gids are stored as kgids
this is valid and the extra layer of translation can be removed.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:15:18 -08:00
Eric W. Biederman
0b4d51b02a sunrpc: Use uid_eq and gid_eq where appropriate
When comparing uids use uid_eq instead of ==.
When comparing gids use gid_eq instead of ==.

And unfortunate cost of type safety.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:15:17 -08:00
Eric W. Biederman
7eaf040b72 sunrpc: Use kuid_t and kgid_t where appropriate
Convert variables that store uids and gids to be of type
kuid_t and kgid_t instead of type uid_t and gid_t.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:15:16 -08:00
Eric W. Biederman
bf37f79437 sunrpc: Use userns friendly constants.
Instead of (uid_t)0 use GLOBAL_ROOT_UID.
Instead of (gid_t)0 use GLOBAL_ROOT_GID.
Instead of (uid_t)-1 use INVALID_UID
Instead of (gid_t)-1 use INVALID_GID.
Instead of NOGROUP use INVALID_GID.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-02-13 06:15:15 -08:00
Linus Torvalds
982197277c Merge branch 'for-3.8' of git://linux-nfs.org/~bfields/linux
Pull nfsd update from Bruce Fields:
 "Included this time:

   - more nfsd containerization work from Stanislav Kinsbursky: we're
     not quite there yet, but should be by 3.9.

   - NFSv4.1 progress: implementation of basic backchannel security
     negotiation and the mandatory BACKCHANNEL_CTL operation.  See

       http://wiki.linux-nfs.org/wiki/index.php/Server_4.0_and_4.1_issues

     for remaining TODO's

   - Fixes for some bugs that could be triggered by unusual compounds.
     Our xdr code wasn't designed with v4 compounds in mind, and it
     shows.  A more thorough rewrite is still a todo.

   - If you've ever seen "RPC: multiple fragments per record not
     supported" logged while using some sort of odd userland NFS client,
     that should now be fixed.

   - Further work from Jeff Layton on our mechanism for storing
     information about NFSv4 clients across reboots.

   - Further work from Bryan Schumaker on his fault-injection mechanism
     (which allows us to discard selective NFSv4 state, to excercise
     rarely-taken recovery code paths in the client.)

   - The usual mix of miscellaneous bugs and cleanup.

  Thanks to everyone who tested or contributed this cycle."

* 'for-3.8' of git://linux-nfs.org/~bfields/linux: (111 commits)
  nfsd4: don't leave freed stateid hashed
  nfsd4: free_stateid can use the current stateid
  nfsd4: cleanup: replace rq_resused count by rq_next_page pointer
  nfsd: warn on odd reply state in nfsd_vfs_read
  nfsd4: fix oops on unusual readlike compound
  nfsd4: disable zero-copy on non-final read ops
  svcrpc: fix some printks
  NFSD: Correct the size calculation in fault_inject_write
  NFSD: Pass correct buffer size to rpc_ntop
  nfsd: pass proper net to nfsd_destroy() from NFSd kthreads
  nfsd: simplify service shutdown
  nfsd: replace boolean nfsd_up flag by users counter
  nfsd: simplify NFSv4 state init and shutdown
  nfsd: introduce helpers for generic resources init and shutdown
  nfsd: make NFSd service structure allocated per net
  nfsd: make NFSd service boot time per-net
  nfsd: per-net NFSd up flag introduced
  nfsd: move per-net startup code to separated function
  nfsd: pass net to __write_ports() and down
  nfsd: pass net to nfsd_set_nrthreads()
  ...
2012-12-20 14:04:11 -08:00
J. Bruce Fields
afc59400d6 nfsd4: cleanup: replace rq_resused count by rq_next_page pointer
It may be a matter of personal taste, but I find this makes the code
clearer.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-12-17 22:00:16 -05:00
J. Bruce Fields
3a28e33111 svcrpc: fix some printks
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-12-17 16:02:40 -05:00
Stanislav Kinsbursky
cd6c596858 SUNRPC: continue run over clients list on PipeFS event instead of break
There are SUNRPC clients, which program doesn't have pipe_dir_name. These
clients can be skipped on PipeFS events, because nothing have to be created or
destroyed. But instead of breaking in case of such a client was found, search
for suitable client over clients list have to be continued. Otherwise some
clients could not be covered by PipeFS event handler.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Cc: stable@vger.kernel.org [>= v3.4]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-17 12:19:16 -05:00
Trond Myklebust
1efc28780b SUNRPC: variable 'svsk' is unused in function bc_send_request
Silence a compile time warning.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-15 17:05:57 -05:00
Trond Myklebust
4a20a988f7 SUNRPC: Handle ECONNREFUSED in xs_local_setup_socket
Silence the unnecessary warning "unhandled error (111) connecting to..."
and convert it to a dprintk for debugging purposes.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-15 17:02:29 -05:00
Andy Adamson
eb96d5c97b SUNRPC handle EKEYEXPIRED in call_refreshresult
Currently, when an RPCSEC_GSS context has expired or is non-existent
and the users (Kerberos) credentials have also expired or are non-existent,
the client receives the -EKEYEXPIRED error and tries to refresh the context
forever.  If an application is performing I/O, or other work against the share,
the application hangs, and the user is not prompted to refresh/establish their
credentials. This can result in a denial of service for other users.

Users are expected to manage their Kerberos credential lifetimes to mitigate
this issue.

Move the -EKEYEXPIRED handling into the RPC layer. Try tk_cred_retry number
of times to refresh the gss_context, and then return -EACCES to the application.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-12 15:36:02 -05:00
Andy Adamson
620038f6d2 SUNRPC set gss gc_expiry to full lifetime
Only use the default GSSD_MIN_TIMEOUT if the gss downcall timeout is zero.
Store the full lifetime in gc_expiry (not 3/4 of the lifetime) as subsequent
patches will use the gc_expiry to determine buffered WRITE behavior in the
face of expired or soon to be expired gss credentials.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-12 15:35:59 -05:00
Trond Myklebust
7ce0171d4f Merge branch 'bugfixes' into nfs-for-next 2012-12-11 09:16:26 -05:00
Stanislav Kinsbursky
756933ee8a SUNRPC: remove redundant "linux/nsproxy.h" includes
This is a cleanup patch.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-12-10 16:25:30 -05:00
Trond Myklebust
c05eecf636 SUNRPC: Don't allow low priority tasks to pre-empt higher priority ones
Currently, the priority queues attempt to be 'fair' to lower priority
tasks by scheduling them after a certain number of higher priority tasks
have run. The problem is that both the transport send queue and
the NFSv4.1 session slot queue have strong ordering requirements.

This patch therefore removes the fairness code in favour of strong
ordering of task priorities.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:53 +01:00
Trond Myklebust
1e1093c7fd NFSv4.1: Don't mess with task priorities in nfs41_setup_sequence
We want to preserve the rpc_task priority for things like writebacks,
that may have differing levels of urgency.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:51 +01:00
J. Bruce Fields
836fbadb96 svcrpc: support multiple-fragment rpc's
Over TCP, RPC's are preceded by a single 4-byte field telling you how
long the rpc is (in bytes).  The spec also allows you to send an RPC in
multiple such records (the high bit of the length field is used to tell
you whether this is the final record).

We've survived for years without supporting this because in practice the
clients we care about don't use it.  But the userland rpc libraries do,
and every now and then an experimental client will run into this.  (Most
recently I noticed it while trying to write a pynfs check.)  And we're
really on the wrong side of the spec here--let's fix this.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-12-04 07:49:24 -05:00
J. Bruce Fields
8af345f58a svcrpc: track rpc data length separately from sk_tcplen
Keep a separate field, sk_datalen, that tracks only the data contained
in a fragment, not including the fragment header.

For now, this is always just max(0, sk_tcplen - 4), but after we allow
multiple fragments sk_datalen will accumulate the total rpc data size
while sk_tcplen only tracks progress receiving the current fragment.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-12-04 07:49:14 -05:00
J. Bruce Fields
6a72ae2e23 svcrpc: fix off-by-4 error in "incomplete TCP record" dprintk
The full reclen doesn't include the fragment header, but sk_tcplen does.
Fix this to make it an apples-to-apples comparison.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-12-04 07:49:06 -05:00
J. Bruce Fields
ad46ccf094 svcrpc: delay minimum-rpc-size check till later
Soon we want to support multiple fragments, in which case it may be
legal for a single fragment to be smaller than 8 bytes, so we'll want to
delay this check till we've reached the last fragment.

Also fix an outdated comment.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-12-04 07:47:58 -05:00
J. Bruce Fields
cc248d4b1d svcrpc: don't byte-swap sk_reclen in place
Byte-swapping in place is always a little dubious.

Let's instead define this field to always be big-endian, and do the
swapping on demand where we need it.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-12-04 07:47:23 -05:00
Trond Myklebust
642fe4d00d SUNRPC: Fix validity issues with rpc_pipefs sb->s_fs_info
rpc_kill_sb() must defer calling put_net() until after the notifier
has been called, since most (all?) of the notifier callbacks assume
that sb->s_fs_info points to a valid net namespace. It also must not
call put_net() if the call to rpc_fill_super was unsuccessful.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=48421

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>
Cc: stable@vger.kernel.org [>= v3.4]
2012-11-08 14:53:28 -05:00
J. Bruce Fields
7032a3dd92 svcrpc: demote some printks to a dprintk
In general I'd rather random bad behavior on the network won't trigger a
printk.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-11-07 19:31:32 -05:00
Trond Myklebust
f994c43d19 SUNRPC: Clean up rpc_bind_new_program
We can and should use the rpc_create_args and __rpc_clone_client()
to change the program and version number on the resulting rpc_client.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:43 -05:00
Weston Andros Adamson
50d2bdb197 SUNRPC: remove BUG_ON from rpc_call_sync
Use WARN_ON_ONCE instead of calling BUG_ON and return -EINVAL when
RPC_TASK_ASYNC flag is passed to rpc_call_sync.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:43 -05:00
Weston Andros Adamson
0a0c2a57bc SUNRPC: remove BUG_ON in rpc_release_task
Replace BUG_ON() with WARN_ON_ONCE().

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:43 -05:00
Weston Andros Adamson
0104729807 SUNRPC: remove BUG_ON in svc_delete_xprt
Replace BUG_ON() with WARN_ON_ONCE().

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:42 -05:00
Weston Andros Adamson
2bd4eef87b SUNRPC: remove BUG_ONs checking RPC_IS_QUEUED
Replace two BUG_ON() calls with WARN_ON_ONCE() and early returns.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:42 -05:00
Weston Andros Adamson
f50ad42837 SUNRPC: remove BUG_ON from __rpc_sleep_on_priority
Replace BUG_ON() with WARN_ON_ONCE().

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:42 -05:00
Weston Andros Adamson
0af39507f6 SUNRPC: remove BUG_ON in svc_register
Instead of calling BUG_ON(), do a WARN_ON_ONCE() and return -EINVAL.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:42 -05:00
Weston Andros Adamson
332e008a44 SUNRPC: remove BUG_ON from encode_rpcb_string
Replace BUG_ON() with WARN_ON_ONCE() and truncate the encoded string if
len > max.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:42 -05:00
Weston Andros Adamson
b8a13d039c SUNRPC: remove BUG_ON from bc_malloc
Replace BUG_ON() with WARN_ON_ONCE() and NULL return - the caller will handle
this like a memory allocation failure.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:42 -05:00
Weston Andros Adamson
18e624ad03 SUNRPC: remove BUG_ON in xdr_shrink_bufhead
Replace bounds checking BUG_ON() with a WARN_ON_ONCE() and resetting
the requested len to the max.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:42 -05:00
Weston Andros Adamson
b25cd058f2 SUNRPC: remove BUG_ONs checking RPCSVC_MAXPAGES
Replace two bounds checking BUG_ON() calls with WARN_ON_ONCE() and resetting
the requested size to RPCSVC_MAXPAGES.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:41 -05:00
Weston Andros Adamson
ff1fdb9b80 SUNRPC: remove BUG_ON in svc_xprt_received
Replace BUG_ON() with a WARN_ON_ONCE() and early return.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:41 -05:00
Weston Andros Adamson
1b7a181907 SUNRPC: remove BUG_ONs from *_reclassify_socket*
Replace multiple BUG_ON() calls with WARN_ON_ONCE() and early return when
sanity checking socket ownership (lock). The bind call will fail if the
socket was unsuccessfully reclassified.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:41 -05:00
Weston Andros Adamson
1bd58aaff4 SUNRPC: remove BUG_ON from svc_pool_map_set_cpumask
Replace BUG_ON() with a WARN() and early return.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:41 -05:00
Weston Andros Adamson
f30dfbba16 SUNRPC: remove two BUG_ON asserts
Replace two BUG_ON() calls checking the RPC_BC_PA_IN_USE flag with
WARN_ON_ONCE().

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:41 -05:00
Weston Andros Adamson
749386e906 SUNRPC: remove BUG_ON in rpc_put_sb_net
Replace BUG_ON() with WARN_ON() - the condition is definitely a misuse
of the API, but shouldn't cause a crash.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:41 -05:00
Weston Andros Adamson
0db74d9a2d SUNRPC: remove BUG_ON calls from cache_read
Replace BUG_ON() with WARN_ON_ONCE() in two parts of cache_read().

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:41 -05:00
Weston Andros Adamson
4c9c52e479 SUNRPC: remove BUG_ON from bc_send
Replace BUG_ON() with WARN_ON_ONCE(). The error condition is a simple
ref counting sanity check and the following code will not free anything
until final put.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:41 -05:00
Weston Andros Adamson
c4ded8d977 SUNRPC: remove BUG_ON from xprt_destroy_backchannel
If max_reqs is 0, do nothing besides the usual dprintks.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:40 -05:00