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path: root/fs/lockd/host.c
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2010-12-16lockd: Add nlm_alloc_host()Chuck Lever
Refactor nlm_host allocation and initialization into a separate function. This will be the common piece of server and client nlm_host lookup logic after the nlm_host cache is split. Small change: use kmalloc() instead of kzalloc(), as we're overwriting almost all fields in the new nlm_host struct with non-zero values immediately after it is allocated. An added benefit is we now have an explicit reference to each field name where it is initialized (for all you cscope fans out there). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-12-16lockd: reorganize nlm_host_rebootedJ. Bruce Fields
Minor reorganization; no change in behavior. This will save some duplicated code after we split the client and server host caches. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> [ cel: Forward-ported to 2.6.37 ] Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-12-16lockd: define host_for_each{_safe} macrosJ. Bruce Fields
We've got a lot of loops like this, and I find them a little easier to read with the macros. More such loops are coming. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> [ cel: Forward-ported to 2.6.37 ] Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-11-15NLM: Fix a regression in lockdTrond Myklebust
Nick Bowler reports: There are no unusual messages on the client... but I just logged into the server and I see lots of messages of the following form: nfsd: request from insecure port (192.168.8.199:35766)! nfsd: request from insecure port (192.168.8.199:35766)! nfsd: request from insecure port (192.168.8.199:35766)! nfsd: request from insecure port (192.168.8.199:35766)! nfsd: request from insecure port (192.168.8.199:35766)! Bisected to commit 9247685088398cf21bcb513bd2832b4cd42516c4 (SUNRPC: Properly initialize sock_xprt.srcaddr in all cases) Apparently, removing the 'transport->srcaddr.ss_family = family' from xs_create_sock() triggers this due to nlmclnt_lookup_host() incorrectly initialising the srcaddr family to AF_UNSPEC. Reported-by: Nick Bowler <nbowler@elliptictech.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-10-01sunrpc: Add net to rpc_create_argsPavel Emelyanov
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2010-02-08lockd: release reference to nsm_handle in nlm_host_rebootedJeff Layton
nsm_reboot_lookup takes a reference to the nsm_handle that it returns, but nlm_host_rebooted never releases that reference. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-08-21sunrpc: add routine for comparing addressesJeff Layton
lockd needs these sort of routines, as does the NFSv4 callback code. Move lockd's routines into common code and rename them so that they can be used by others. Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-08-09lockd: Replace nlm_clear_port()Chuck Lever
Clean up: Use shared rpc_set_port() function instead of nlm_clear_port(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-01-06NSM: Remove include/linux/lockd/sm_inter.hChuck Lever
Clean up: The include/linux/lockd/sm_inter.h header is nearly empty now. Remove it. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NLM: Remove "create" argument from nsm_find()Chuck Lever
Clean up: nsm_find() now has only one caller, and that caller unconditionally sets the @create argument. Thus the @create argument is no longer needed. Since nsm_find() now has a more specific purpose, pick a more appropriate name for it. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NLM: Call nsm_reboot_lookup() instead of nsm_find()Chuck Lever
Invoke the newly introduced nsm_reboot_lookup() function in nlm_host_rebooted() instead of nsm_find(). This introduces just one behavioral change: debugging messages produced during reboot notification will now appear when the NLMDBG_MONITOR flag is set, but not when the NLMDBG_HOSTCACHE flag is set. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NLM: Decode "priv" argument of NLMPROC_SM_NOTIFY as an opaqueChuck Lever
The NLM XDR decoders for the NLMPROC_SM_NOTIFY procedure should treat their "priv" argument truly as an opaque, as defined by the protocol, and let the upper layers figure out what is in it. This will make it easier to modify the contents and interpretation of the "priv" argument, and keep knowledge about what's in "priv" local to fs/lockd/mon.c. For now, the NLM and NSM implementations should behave exactly as they did before. The formation of the address of the rebooted host in nlm_host_rebooted() may look a little strange, but it is the inverse of how nsm_init_private() forms the private cookie. Plus, it's going away soon anyway. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NLM: Change nlm_host_rebooted() to take a single nlm_reboot argumentChuck Lever
Pass the nlm_reboot data structure directly from the NLMPROC_SM_NOTIFY XDR decoders to nlm_host_rebooted(). This eliminates some packing and unpacking of the NLMPROC_SM_NOTIFY results, and prepares for passing these results, including the "priv" cookie, directly to a lookup routine in fs/lockd/mon.c. This patch changes code organization but should not cause any behavioral change. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Move nsm_find() to fs/lockd/mon.cChuck Lever
The nsm_find() function sets up fresh nsm_handle entries. This is where we will store the "priv" cookie used to lookup nsm_handles during reboot recovery. The cookie will be constructed when nsm_find() creates a new nsm_handle. As much as possible, I would like to keep everything that handles a "priv" cookie in fs/lockd/mon.c so that all the smarts are in one source file. That organization should make it pretty simple to see how all this works. To me, it makes more sense than the current arrangement to keep nsm_find() with nsm_monitor() and nsm_unmonitor(). So, start reorganizing by moving nsm_find() into fs/lockd/mon.c. The nsm_release() function comes along too, since it shares the nsm_lock global variable. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NSM: Release nsmhandle in nlm_destroy_hostChuck Lever
The nsm_handle's reference count is bumped in nlm_lookup_host(). It should be decremented in nlm_destroy_host() to make it easier to see the balance of these two operations. Move the nsm_release() call to fs/lockd/host.c. The h_nsmhandle pointer is set in nlm_lookup_host(), and never cleared. The nlm_destroy_host() function is never called for the same nlm_host twice, so h_nsmhandle won't ever be NULL when nsm_unmonitor() is called. All references to the nlm_host are gone before it is freed. We can skip making h_nsmhandle NULL just before the nlm_host is deallocated. It's also likely we can remove the h_nsmhandle NULL check in nlmsvc_is_client() as well, but we can do that later when rearchitect- ing the nlm_host cache. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NLM: Add helper to handle IPv4 addressesChuck Lever
Clean up: introduce a helper function to generate IPv4 addresses using the same style as the IPv6 helper function we just added. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NLM: Support IPv6 scope IDs in nlm_display_address()Chuck Lever
Scope ID support is needed since the kernel's NSM implementation is about to use these displayed addresses as a mon_name in some cases. When nsm_use_hostnames is zero, without scope ID support NSM will fail to handle peers that contact us via a link-local address. Link-local addresses do not work without an interface ID, which is stored in the sockaddr's sin6_scope_id field. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NLM: Remove AF_UNSPEC arm in nlm_display_address()Chuck Lever
AF_UNSPEC support is no longer needed in nlm_display_address() now that a presentation address is no longer generated for the h_srcaddr field. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06NLM: Remove address eye-catcher buffers from nlm_hostChuck Lever
The h_name field in struct nlm_host is a just copy of h_nsmhandle->sm_name. Likewise, the contents of the h_addrbuf field should be identical to the sm_addrbuf field. The h_srcaddrbuf field is used only in one place for debugging. We can live without this until we get %pI formatting for printk(). Currently these buffers are 48 bytes, but we need to support scope IDs in IPv6 presentation addresses, which means making the buffers even larger. Instead, let's find ways to eliminate them to save space. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-12-30Merge branch 'devel' into nextTrond Myklebust
2008-12-23NLM: allow lockd requests from an unprivileged portChuck Lever
If the admin has specified the "noresvport" option for an NFS mount point, the kernel's NFS client uses an unprivileged source port for the main NFS transport. The kernel's lockd client should use an unprivileged port in this case as well. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-12-15Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/e1000e/ich8lan.c
2008-11-24NLM: client-side nlm_lookup_host() should avoid matching on srcaddrChuck Lever
Since commit c98451bd, the loop in nlm_lookup_host() unconditionally compares the host's h_srcaddr field to the incoming source address. For client-side nlm_host entries, both are always AF_UNSPEC, so this check is unnecessary. Since commit 781b61a6, which added support for AF_INET6 addresses to nlm_cmp_addr(), nlm_cmp_addr() now returns FALSE for AF_UNSPEC addresses, which causes nlm_lookup_host() to create a fresh nlm_host entry every time it is called on the client. These extra entries will eventually expire once the server is unmounted, so the impact of this regression, introduced with lockd IPv6 support in 2.6.28, should be minor. We could fix this by adding an arm in nlm_cmp_addr() for AF_UNSPEC addresses, but really, nlm_lookup_host() shouldn't be matching on the srcaddr field for client-side nlm_host lookups. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-10-31fs: replace NIPQUAD()Harvey Harrison
Using NIPQUAD() with NIPQUAD_FMT, %d.%d.%d.%d or %u.%u.%u.%u can be replaced with %pI4 Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-29net: replace %p6 with %pI6Harvey Harrison
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-28misc: replace NIP6_FMT with %p6 format specifierHarvey Harrison
The iscsi_ibft.c changes are almost certainly a bugfix as the pointer 'ip' is a u8 *, so they never print the last 8 bytes of the IPv6 address, and the eight bytes they do print have a zero byte with them in each 16-bit word. Other than that, this should cause no difference in functionality. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-03lockd: Adjust nlmsvc_lookup_host() to accomodate AF_INET6 addressesChuck Lever
Fix up nlmsvc_lookup_host() to pass AF_INET6 source addresses to nlm_lookup_host(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-10-03lockd: Adjust nlmclnt_lookup_host() signature to accomodate non-AF_INETChuck Lever
Pass a struct sockaddr * and a length to nlmclnt_lookup_host() to accomodate non-AF_INET family addresses. As a side benefit, eliminate the hostname_len argument, as the hostname is always NUL-terminated. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-10-03lockd: Support non-AF_INET addresses in nlm_lookup_host()Chuck Lever
Use struct sockaddr * and length in nlm_lookup_host_info to all callers to pass in either AF_INET or AF_INET6 addresses. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-10-03NLM: Convert nlm_lookup_host() to use a single argumentChuck Lever
The nlm_lookup_host() function already has a large number of arguments, and I'm about to add a few more. As a clean up, convert the function to use a single data structure argument. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29lockd: Update nsm_find() to support non-AF_INET addressesChuck Lever
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29lockd: Combine __nsm_find() and nsm_find().Chuck Lever
Clean up: Having two separate functions doesn't add clarity, so eliminate one of them. Use contemporary kernel coding conventions where appropriate. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29lockd: Support AF_INET6 when hashing addresses in nlm_lookup_hostChuck Lever
Adopt an approach similar to the RPC server's auth cache (from Aurelien Charbon and Brian Haley). Note nlm_lookup_host()'s existing IP address hash function has the same issue with correctness on little-endian systems as the original IPv4 auth cache hash function, so I've also updated it with a hash function similar to the new auth cache hash function. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29lockd: Teach nlm_cmp_addr() to support AF_INET6 addressesChuck Lever
Update the nlm_cmp_addr() helper to support AF_INET6 as well as AF_INET addresses. New version takes two "struct sockaddr *" arguments instead of "struct sockaddr_in *" arguments. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29NSM: Use sockaddr_storage for sm_addr fieldChuck Lever
To store larger addresses in the nsm_handle structure, make sm_addr a sockaddr_storage. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29lockd: Use sockaddr_storage for h_saddr fieldChuck Lever
To store larger addresses in the nlm_host structure, make h_saddr a sockaddr_storage. And let's call it something more self-explanatory: "saddr" could easily be mistaken for "server address". Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29lockd: Use sockaddr_storage + length for h_addr fieldChuck Lever
To store larger addresses in the nlm_host structure, make h_addr a sockaddr_storage, and add an address length field. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29lockd: Add address family-agnostic helper for zeroing the port numberChuck Lever
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29lockd: Specify address family for source addressChuck Lever
Make sure an address family is specified for source addresses passed to nlm_lookup_host(). nlm_lookup_host() will need this when it becomes capable of dealing with AF_INET6 addresses. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29lockd: address-family independent printable addressesChuck Lever
Knowing which source address is used for communicating with remote NLM services can be helpful for debugging configuration problems on hosts with multiple addresses. Keep the dprintk debugging here, but adapt it so it displays AF_INET6 addresses properly. There are also a couple of dprintk clean-ups as well. At some point we will aggregate the helpers that display presentation format addresses into a single set of shared helpers. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29NLM: Clean up before introducing new debugging messagesChuck Lever
We're about to introduce some extra debugging messages in nlm_lookup_host(). Bring the coding style up to date first so we can cleanly introduce the new debugging messages. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-04-24Merge git://git.linux-nfs.org/projects/trondmy/nfs-2.6Linus Torvalds
* git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (80 commits) SUNRPC: Invalidate the RPCSEC_GSS session if the server dropped the request make nfs_automount_list static NFS: remove duplicate flags assignment from nfs_validate_mount_data NFS - fix potential NULL pointer dereference v2 SUNRPC: Don't change the RPCSEC_GSS context on a credential that is in use SUNRPC: Fix a race in gss_refresh_upcall() SUNRPC: Don't disconnect more than once if retransmitting NFSv4 requests SUNRPC: Remove the unused export of xprt_force_disconnect SUNRPC: remove XS_SENDMSG_RETRY SUNRPC: Protect creds against early garbage collection NFSv4: Attempt to use machine credentials in SETCLIENTID calls NFSv4: Reintroduce machine creds NFSv4: Don't use cred->cr_ops->cr_name in nfs4_proc_setclientid() nfs: fix printout of multiword bitfields nfs: return negative error value from nfs{,4}_stat_to_errno NLM/lockd: Ensure client locking calls use correct credentials NFS: Remove the buggy lock-if-signalled case from do_setlk() NLM/lockd: Fix a race when cancelling a blocking lock NLM/lockd: Ensure that nlmclnt_cancel() returns results of the CANCEL call NLM: Remove the signal masking in nlmclnt_proc/nlmclnt_cancel ...
2008-04-23lockd: convert nsm_mutex to a spinlockJ. Bruce Fields
There's no reason for a mutex here, except to allow an allocation under the lock, which we can avoid with the usual trick of preallocating memory for the new object and freeing it if it turns out to be unnecessary. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-04-23lockd: clean up __nsm_find()J. Bruce Fields
Use list_for_each_entry(). Also, in keeping with kernel style, make the normal case (kzalloc succeeds) unindented and handle the abnormal case with a goto. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-04-23lockd: fix race in nlm_release()J. Bruce Fields
The sm_count is decremented to zero but left on the nsm_handles list. So in the space between decrementing sm_count and acquiring nsm_mutex, it is possible for another task to find this nsm_handle, increment the use count and then enter nsm_release itself. Thus there's nothing to prevent the nsm being freed before we acquire nsm_mutex here. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-04-23knfsd: Remove NLM_HOST_MAX and associated logic.NeilBrown
Lockd caches information about hosts that have recently held locks to expedite the taking of further locks. It periodically discards this information for hosts that have not been used for a few minutes. lockd currently has a value NLM_HOST_MAX, and changes the 'garbage collection' behaviour when the number of hosts exceeds this threshold. However its behaviour is strange, and likely not what was intended. When the number of hosts exceeds the max, it scans *less* often (every 2 minutes vs every minute) and allows unused host information to remain around longer (5 minutes instead of 2). Having this limit is of dubious value anyway, and we have not suffered from the code not getting the limit right, so remove the limit altogether. We go with the larger values (discard 5 minute old hosts every 2 minutes) as they are probably safer. Maybe the periodic garbage collection should be replace to with 'shrinker' handler so we just respond to memory pressure.... Acked-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-03-19NLM: NLM protocol version numbers are u32Chuck Lever
Clean up: RPC protocol version numbers are u32. Make sure we use an appropriate type for NLM version numbers when calling nlm_lookup_host(). Eliminates a harmless mixed sign comparison in nlm_host_lookup(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-10NLM: have server-side RPC clients default to soft RPC tasksJeff Layton
Now that it no longer does an RPC ping, lockd always ends up queueing an RPC task for the GRANT_MSG callback. But, it also requeues the block for later attempts. Since these are hard RPC tasks, if the client we're calling back goes unresponsive the GRANT_MSG callbacks can stack up in the RPC queue. Fix this by making server-side RPC clients default to soft RPC tasks. lockd requeues the block anyway, so this should be OK. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-10NLM: set RPC_CLNT_CREATE_NOPING for NLM RPC clientsJeff Layton
It's currently possible for an unresponsive NLM client to completely lock up a server's lockd. The scenario is something like this: 1) client1 (or a process on the server) takes a lock on a file 2) client2 tries to take a blocking lock on the same file and awaits the callback 3) client2 goes unresponsive (plug pulled, network partition, etc) 4) client1 releases the lock ...at that point the server's lockd will try to queue up a GRANT_MSG callback for client2, but first it requeues the block with a timeout of 30s. nlm_async_call will attempt to bind the RPC client to client2 and will call rpc_ping. rpc_ping entails a sync RPC call and if client2 is unresponsive it will take around 60s for that to time out. Once it times out, it's already time to retry the block and the whole process repeats. Once in this situation, nlmsvc_retry_blocked will never return until the host starts responding again. lockd won't service new calls. Fix this by skipping the RPC ping on NLM RPC clients. This makes nlm_async_call return quickly when called. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01NLM: tear down RPC clients in nlm_shutdown_hostsJeff Layton
It's possible for a RPC to outlive the lockd daemon that created it, so we need to make sure that all RPC's are killed when lockd is coming down. When nlm_shutdown_hosts is called, kill off all RPC tasks associated with the host. Since we need to wait until they have all gone away, we might as well just shut down the RPC client altogether. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>