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2012-02-27SUNRPC: move waitq from RPC pipe to RPC inodeStanislav Kinsbursky1-1/+1
Currently, wait queue, used for polling of RPC pipe changes from user-space, is a part of RPC pipe. But the pipe data itself can be released on NFS umount prior to dentry-inode pair, connected to it (is case of this pair is open by some process). This is not a problem for almost all pipe users, because all PipeFS file operations checks pipe reference prior to using it. Except evenfd. This thing registers itself with "poll" file operation and thus has a reference to pipe wait queue. This leads to oopses on destroying eventfd after NFS umount (like rpc_idmapd do) since not pipe data left to the point already. The solution is to wait queue from pipe data to internal RPC inode data. This looks more logical, because this wiat queue used only for user-space processes, which already holds inode reference. Note: upcalls have to get pipe->dentry prior to dereferecing wait queue to make sure, that mount point won't disappear from underneath us. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-17NFS: include filelayout DS rpc stats in mountstatsWeston Andros Adamson2-2/+5
Include RPC statistics from all data servers in /proc/self/mountstats for pNFS filelayout mounts. Signed-off-by: Weston Andros Adamson <dros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-16SUNRPC: Use KERN_DEFAULT for debugging printk'sChuck Lever1-1/+5
Our dprintk() debugging facility doesn't specify any verbosity level for it's printk() calls, but it should. The default verbosity for printk's is KERN_DEFAULT. You might argue that these are debugging printk's and thus the verbosity should be KERN_DEBUG. That would mean that to see NFS and SUNRPC debugging output an admin would also have to boost the syslog verbosity, which would be insufferably noisy. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-16SUNRPC: add sending,pending queue and max slot to xprt statsAndy Adamson2-3/+6
With static RPC slots, the xprt backlog queue stats were useful in showing when the transport (TCP) was starved by lack of RPC slots. The new dynamic RPC slot code, commit d9ba131d8f58c0d2ff5029e7002ab43f913b36f9, always provides an RPC slot and so only uses the xprt backlog queue when the tcp_max_slot_table_entries value has been hit or when an allocation error occurs. All requests are now placed on the xprt sending or pending queue which need to be monitored for debugging. The max_slot stat shows the maximum number of dynamic RPC slots reached which is useful when debugging performance issues. Add the new fields at the end of the mountstats xprt stanza so that mountstats outputs the previous correct values and ignores the new fields. Bump NFS_IOSTATS_VERS. Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-15SUNRPC: Ensure that we can trace waitqueues when !defined(CONFIG_SYSCTL)Trond Myklebust2-2/+16
The tracepoint code relies on the queue->name being defined in order to be able to display the name of the waitqueue on which an RPC task is sleeping. Reported-by: Randy Dunlap <rdunlap@xenotime.net> Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Randy Dunlap <rdunlap@xenotime.net>
2012-02-15Lockd: shutdown NLM hosts in network namespace contextStanislav Kinsbursky1-0/+1
Lockd now managed in network namespace context. And this patch introduces network namespace related NLM hosts shutdown in case of releasing per-net Lockd resources. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-15LockD: make nlm hosts network namespace awareStanislav Kinsbursky2-1/+4
This object depends on RPC client, and thus on network namespace. So let's make it's allocation and lookup in network namespace context. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-15Lockd: per-net up and down routines introducedStanislav Kinsbursky1-0/+2
This patch introduces per-net Lockd initialization and destruction routines. The logic is the same as in global Lockd up and down routines. Probably the solution is not the best one. But at least it looks clear. So per-net "up" routine are called only in case of lockd is running already. If per-net resources are not allocated yet, then service is being registered with local portmapper and lockd sockets created. Per-net "down" routine is called on every lockd_down() call in case of global users counter is not zero. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-15SUNRPC: service destruction in network namespace contextStanislav Kinsbursky1-1/+1
v2: Added comment to BUG_ON's in svc_destroy() to make code looks clearer. This patch introduces network namespace filter for service destruction function. Nothing special here - just do exactly the same operations, but only for tranports in passed networks namespace context. BTW, BUG_ON() checks for empty service transports lists were returned into svc_destroy() function. This is because of swithing generic svc_close_all() to networks namespace dependable svc_close_net(). Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-15NFSv4.1: Add a module parameter to set the number of session slotsTrond Myklebust1-2/+3
Add the module parameter 'max_session_slots' to set the initial number of slots that the NFSv4.1 client will attempt to negotiate with the server. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-15NFSv4.1: Convert slotid from u8 to u32Trond Myklebust2-4/+5
It is perfectly legal to negotiate up to 2^32-1 slots in the protocol, and with 10GigE, we are already seeing that 255 slots is far too limiting. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-06NFS: Fall back on old idmapper if request_key() failsBryan Schumaker1-15/+0
This patch removes the CONFIG_NFS_USE_NEW_IDMAPPER compile option. First, the idmapper will attempt to map the id using /sbin/request-key and nfsidmap. If this fails (if /etc/request-key.conf is not configured properly) then the idmapper will call the legacy code to perform the mapping. I left a comment stating where the legacy code begins to make it easier for somebody to remove in the future. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-06SUNRPC: Change the default limit to the number of TCP slotsTrond Myklebust2-2/+2
Since the scheme of limiting the number of TCP slots to whatever will fit in the current TCP window seems to be working well (Andy reports getting within 20% of the 'iperf' send performance on a 10GigE link) we should just let that be the default mode of operation. Users may still set their own limits using the tcp_max_slot_table_entries parameter if they need to. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-06SUNRPC: Adding status trace pointsSteve Dickson1-0/+53
This patch adds three trace points to the status routines in the sunrpc state machine. The goal of these trace points is to give an Admin the ability to check on binding status or connection status to see if there is a potential problem. Signed-off-by: Steve Dickson <steved@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-06SUNRPC: Fix up sunrpc trace eventsTrond Myklebust1-3/+3
The reporting of the RPC queue name needs to use the __string() event interface. Reported-by: Neil Horman <nhorman@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: Add trace events to the sunrpc subsystemTrond Myklebust2-1/+125
Add declarations to allow tracing of RPC call creation, running, sleeping, and destruction. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: constify the rpc_programTrond Myklebust5-14/+14
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: constify rpc_program->nameTrond Myklebust1-2/+2
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: constify rpc_clnt fields cl_server and cl_protnameTrond Myklebust1-5/+4
...and get rid of the superfluous cl_inline_name. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: search for service transports in network namespace contextStanislav Kinsbursky1-1/+2
Service transports are parametrized by network namespace. And thus lookup of transport instance have to take network namespace into account. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Acked-by: J. Bruce Fields <bfields@redhat.com>
2012-01-31SUNRPC: register service stats /proc entries in passed network namespace contextStanislav Kinsbursky1-4/+4
This patch makes it possible to create NFSd program entry ("/proc/net/rpc/nfsd") in passed network namespace context instead of hard-coded "init_net". Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31sunrpc: fix stats.h for CONFIG_PROC_FS not enabledRandy Dunlap1-2/+2
Fix build errors in linux/sunrpc/stats.h when CONFIG_PROC_FS is not enabled: - add parameter names to inline functions - fix placement of '(' in rpc_proc_unregister() Fixes these errors: include/linux/sunrpc/stats.h:72:63: error: parameter name omitted include/linux/sunrpc/stats.h:73:46: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'net' Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: register RPC stats /proc entries in passed network namespace contextStanislav Kinsbursky1-4/+4
This patch makes it possible to create NFS program entry ("/proc/net/rpc/nfs") in passed network namespace context instead of hard-coded "init_net". Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: generic cache register routines removedStanislav Kinsbursky1-2/+0
All cache users now uses network-namespace-aware routines, so generic ones are obsolete. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Acked-by: J. Bruce Fields <bfields@redhat.com>
2012-01-31SUNRPC: create GSS auth cache per network namespaceStanislav Kinsbursky1-0/+2
This patch makes GSS auth cache details allocated and registered per network namespace context. Thus with this patch rsi_cache and rsc_cache contents for network namespace "X" are controlled from proc file system mount for the same network namespace "X". Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Acked-by: J. Bruce Fields <bfields@redhat.com>
2012-01-31SUNRPC: cache creation and destruction routines introducedStanislav Kinsbursky1-0/+4
This patch prepares infrastructure for network namespace aware cache detail allocation. One note about adding network namespace link to cache structure. It's going to be used later in NFS DNS cache parsing routine (nfs_dns_parse for rpc_pton() call). Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Acked-by: J. Bruce Fields <bfields@redhat.com>
2012-01-31SUNRPC: unregister service on creation in current network namespaceStanislav Kinsbursky1-4/+5
On service shutdown we can be sure, that no more users of it left except current. Thus it looks like using current network namespace context is safe in this case. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: pass network namespace to service registering routinesStanislav Kinsbursky1-1/+1
Lockd and NFSd services will handle requests from and to many network nsamespaces. And thus have to be registered and unregistered per network namespace. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: parametrize rpc_uaddr2sockaddr() by network contextStanislav Kinsbursky1-1/+1
Parametrize rpc_uaddr2sockaddr() by network context and thus force it's callers to pass in network context instead of using hard-coded "init_net". Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: parametrize rpc_pton() by network contextStanislav Kinsbursky1-1/+1
Parametrize rpc_pton() by network context and thus force it's callers to pass in network context instead of using hard-coded "init_net". Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: parametrize local rpcbind clients creation with net nsStanislav Kinsbursky1-2/+2
These client are per network namespace and thus can be created for different network namespaces. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: register rpcbind programs in passed network namespase contextStanislav Kinsbursky1-2/+3
Registering rpcbind program requires rpcbind clients, which are per network namespace context. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: Fix potential races in xprt_lock_write_next()Trond Myklebust1-0/+3
We have to ensure that the wake up from the waitqueue and the assignment of xprt->snd_task are atomic. We can do this by assigning the snd_task while under the waitqueue spinlock. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31NFSv4: Replace lock_owner->ld_id with an ida based allocatorTrond Myklebust1-1/+1
Again, We're unlikely to ever need more than 2^31 simultaneous lock owners, so let's replace the custom allocator. Now that there are no more users, we can also get rid of the custom allocator code. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31NFSv4: Replace state_owner->so_owner_id with an ida based allocatorTrond Myklebust1-1/+2
We're unlikely to ever need more than 2^31 simultaneous open owners, so let's replace the custom allocator with the generic ida allocator. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31NFS: Remove unnecessary includes from linux/nfs_fs_i.hTrond Myklebust2-5/+0
Also from linux/nfs_xdr.h. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: kernel PipeFS mount point creation routines removedStanislav Kinsbursky1-2/+0
This patch removes static rpc_mnt variable and its creation and destruction routines, because they are not used anymore. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31NFS: idmap PipeFS notifier introducedStanislav Kinsbursky2-10/+18
v2: 1) Added "nfs_idmap_init" and "nfs_idmap_quit" definitions for kernels built without CONFIG_NFS_V4 option set. This patch subscribes NFS clients to RPC pipefs notifications. Idmap notifier is registering on NFS module load. This notifier callback is responsible for creation/destruction of PipeFS idmap pipe dentry for NFS4 clients. Since ipdmap pipe is created in rpc client pipefs directory, we have make sure, that this directory has been created already. IOW RPC client notifier callback has been called already. To achive this, PipeFS notifier priorities has been introduced (RPC clients notifier priority is greater than NFS idmap one). But this approach gives another problem: unlink for RPC client directory will be called before NFS idmap pipe unlink on UMOUNT event and will fail, because directory is not empty. The solution, introduced in this patch, is to try to remove client directory once again after idmap pipe was unlinked. This looks like ugly hack, so probably it should be replaced in some more elegant way. Note that no locking required in notifier callback because PipeFS superblock pointer is passed as an argument from it's creation or destruction routine and thus we can be sure about it's validity. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31NFS: make NFS client allocated per network namespace contextStanislav Kinsbursky1-0/+1
This patch adds new net variable to nfs_client structure. This variable is set on NFS client creation and cheched during matching NFS client search. Initially current->nsproxy->net_ns is used as network namespace owner for new NFS client to create. This network namespace pointer is set during mount options parsing and thus can be passed from user-spave utils in future if will be necessary. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: split cache creation and PipeFS registrationStanislav Kinsbursky1-0/+2
This precursor patch splits SUNRPC cache creation and PipeFS registartion. It's required for latter split of NFS DNS resolver cache creation per network namespace context and PipeFS registration/unregistration on MOUNT/UMOUNT events. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: remove RPC PipeFS mount point reference from RPC clientStanislav Kinsbursky1-1/+1
This is a cleanup patch. We don't need this reference anymore. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: subscribe RPC clients to pipefs notificationsStanislav Kinsbursky1-0/+2
This patch subscribes RPC clients to RPC pipefs notifications. RPC clients notifier block is registering with pipefs initialization during SUNRPC module init. This notifier callback is responsible for RPC client PipeFS directory and GSS pipes creation. For pipes creation and destruction two additional callbacks were added to struct rpc_authops. Note that no locking required in notifier callback because PipeFS superblock pointer is passed as an argument from it's creation or destruction routine and thus we can be sure about it's validity. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: make SUNPRC clients list per network namespace contextStanislav Kinsbursky1-1/+2
This patch moves static SUNRPC clients list and it's lock to sunrpc_net structure. Currently this list is used only for debug purposes. But later it will be used also for selecting clients by networks namespace on PipeFS mount/umount events. Per-network namespace lists will make this faster and simplier. Note: client list is taken from "init_net" network namespace context in rpc_show_tasks(). This will be changed some day later with making SUNRPC sysctl's per network namespace context. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: handle RPC client pipefs dentries by network namespace aware routinesStanislav Kinsbursky1-1/+1
v2: 1) "Over-put" of PipeFS mount point fixed. Fix is ugly, but allows to bisect the patch set. And it will be removed later in the series. This patch makes RPC clients PipeFs dentries allocations in it's owner network namespace context. RPC client pipefs dentries creation logic has been changed: 1) Pipefs dentries creation by sb was moved to separated function, which will be used for handling PipeFS mount notification. 2) Initial value of RPC client PipeFS dir dentry is set no NULL now. RPC client pipefs dentries cleanup logic has been changed: 1) Cleanup is done now in separated rpc_remove_pipedir() function, which takes care about pipefs superblock locking. Also this patch removes slashes from cb_program.pipe_dir_name and from NFS_PIPE_DIRNAME to make rpc_d_lookup_sb() work. This doesn't affect vfs_path_lookup() results in nfs4blocklayout_init() since this slash is cutted off anyway in link_path_walk(). Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: split SUNPRC PipeFS dentry and private pipe data creationStanislav Kinsbursky1-2/+5
This patch is a final step towards to removing PipeFS inode references from kernel code other than PipeFS itself. It makes all kernel SUNRPC PipeFS users depends on pipe private data, which state depend on their specific operations, etc. This patch completes SUNRPC PipeFS preparations and allows to create pipe private data and PipeFS dentries independently. Next step will be making SUNPRC PipeFS dentries allocated by SUNRPC PipeFS network namespace aware routines. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNPRC: cleanup RPC PipeFS pipes upcall interfaceStanislav Kinsbursky1-1/+1
RPC pipe upcall doesn't requires only private pipe data. Thus RPC inode references in this code can be removed. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: split SUNPRC PipeFS pipe data and inode creationStanislav Kinsbursky1-3/+7
Generally, pipe data is used only for pipes, and thus allocating space for it on every RPC inode allocation is redundant. This patch splits private SUNRPC PipeFS pipe data and inode, makes pipe data allocated only for pipe inodes. This patch is also is a next step towards to to removing PipeFS inode references from kernel code other than PipeFS itself. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: replace inode lock with pipe lock for RPC PipeFS operationsStanislav Kinsbursky1-0/+1
Currenly, inode i_lock is used to provide concurrent access to SUNPRC PipeFS pipes. It looks redundant, since now other use of inode is present in most of these places and thus can be easely replaced, which will allow to remove most of inode references from PipeFS code. This is a first step towards to removing PipeFS inode references from kernel code other than PipeFS itself. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: pipefs per-net operations helper introducedStanislav Kinsbursky1-0/+3
During per-net pipes creation and destruction we have to make sure, that pipefs sb exists for the whole creation/destruction cycle. This is done by using special mutex which controls pipefs sb reference on network namespace context. Helper consists of two parts: first of them (rpc_get_dentry_net) searches for dentry with specified name and returns with mutex taken on success. When pipe creation or destructions is completed, caller should release this mutex by rpc_put_dentry_net call. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31SUNRPC: pipefs dentry lookup helper introducedStanislav Kinsbursky1-0/+3
In all places, where pipefs dentries are created, only directory inode is actually required to create new dentry. And all this directories has root pipefs dentry as their parent. So we actually don't need this pipefs mount point at all if some pipefs lookup method will be provided. IOW, all we really need is just superblock and simple lookup method to find root's child dentry with appropriate name. And this patch introduces this method. Note, that no locking implemented in rpc_d_lookup_sb(). So it can be used only in case of assurance, that pipefs superblock still exist. IOW, we can use this method only in pipefs mount-umount notification subscribers callbacks. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>