aboutsummaryrefslogtreecommitdiff
path: root/include/linux/sunrpc
AgeCommit message (Collapse)Author
2009-03-28SUNRPC: Clean up svc_find_xprt() calling sequenceChuck Lever
Clean up: add documentating comment and use appropriate data types for svc_find_xprt()'s arguments. This also eliminates a mixed sign comparison: @port was an int, while the return value of svc_xprt_local_port() is an unsigned short. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-03-28SUNRPC: Clean up static inline functions in svc_xprt.hChuck Lever
Clean up: Enable the use of const arguments in higher level svc_ APIs by adding const to the arguments of the helper functions in svc_xprt.h Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-03-19SUNRPC: Add the equivalent of the linger and linger2 timeouts to RPC socketsTrond Myklebust
This fixes a regression against FreeBSD servers as reported by Tomas Kasparek. Apparently when using RPC over a TCP socket, the FreeBSD servers don't ever react to the client closing the socket, and so commit e06799f958bf7f9f8fae15f0c6f519953fb0257c (SUNRPC: Use shutdown() instead of close() when disconnecting a TCP socket) causes the setup to hang forever whenever the client attempts to close and then reconnect. We break the deadlock by adding a 'linger2' style timeout to the socket, after which, the client will abort the connection using a TCP 'RST'. The default timeout is set to 15 seconds. A subsequent patch will put it under user control by means of a systctl. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-03-18SUNRPC: Clean up static inline functions in svc_xprt.hChuck Lever
Clean up: Enable the use of const arguments in higher level svc_ APIs by adding const to the arguments of the helper functions in svc_xprt.h Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18knfsd: add file to export stats about nfsd poolsGreg Banks
Add /proc/fs/nfsd/pool_stats to export to userspace various statistics about the operation of rpc server thread pools. This patch is based on a forward-ported version of knfsd-add-pool-thread-stats which has been shipping in the SGI "Enhanced NFS" product since 2006 and which was previously posted: http://article.gmane.org/gmane.linux.nfs/10375 It has also been updated thus: * moved EXPORT_SYMBOL() to near the function it exports * made the new struct struct seq_operations const * used SEQ_START_TOKEN instead of ((void *)1) * merged fix from SGI PV 990526 "sunrpc: use dprintk instead of printk in svc_pool_stats_*()" by Harshula Jayasuriya. * merged fix from SGI PV 964001 "Crash reading pool_stats before nfsds are started". Signed-off-by: Greg Banks <gnb@sgi.com> Signed-off-by: Harshula Jayasuriya <harshula@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18knfsd: avoid overloading the CPU scheduler with enormous load averagesGreg Banks
Avoid overloading the CPU scheduler with enormous load averages when handling high call-rate NFS loads. When the knfsd bottom half is made aware of an incoming call by the socket layer, it tries to choose an nfsd thread and wake it up. As long as there are idle threads, one will be woken up. If there are lot of nfsd threads (a sensible configuration when the server is disk-bound or is running an HSM), there will be many more nfsd threads than CPUs to run them. Under a high call-rate low service-time workload, the result is that almost every nfsd is runnable, but only a handful are actually able to run. This situation causes two significant problems: 1. The CPU scheduler takes over 10% of each CPU, which is robbing the nfsd threads of valuable CPU time. 2. At a high enough load, the nfsd threads starve userspace threads of CPU time, to the point where daemons like portmap and rpc.mountd do not schedule for tens of seconds at a time. Clients attempting to mount an NFS filesystem timeout at the very first step (opening a TCP connection to portmap) because portmap cannot wake up from select() and call accept() in time. Disclaimer: these effects were observed on a SLES9 kernel, modern kernels' schedulers may behave more gracefully. The solution is simple: keep in each svc_pool a counter of the number of threads which have been woken but have not yet run, and do not wake any more if that count reaches an arbitrary small threshold. Testing was on a 4 CPU 4 NIC Altix using 4 IRIX clients, each with 16 synthetic client threads simulating an rsync (i.e. recursive directory listing) workload reading from an i386 RH9 install image (161480 regular files in 10841 directories) on the server. That tree is small enough to fill in the server's RAM so no disk traffic was involved. This setup gives a sustained call rate in excess of 60000 calls/sec before being CPU-bound on the server. The server was running 128 nfsds. Profiling showed schedule() taking 6.7% of every CPU, and __wake_up() taking 5.2%. This patch drops those contributions to 3.0% and 2.2%. Load average was over 120 before the patch, and 20.9 after. This patch is a forward-ported version of knfsd-avoid-nfsd-overload which has been shipping in the SGI "Enhanced NFS" product since 2006. It has been posted before: http://article.gmane.org/gmane.linux.nfs/10374 Signed-off-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18nfs: replace uses of __constant_{endian}Harvey Harrison
The base versions handle constant folding now, none of these headers are exported to userspace, so the __ prefixed versions are not necessary. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Reviewed-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-11SUNRPC: dynamically load RPC transport modules on-demandTom Talpey
Provide an api to attempt to load any necessary kernel RPC client transport module automatically. By convention, the desired module name is "xprt"+"transport name". For example, when NFS mounting with "-o proto=rdma", attempt to load the "xprtrdma" module. Signed-off-by: Tom Talpey <tmtalpey@gmail.com> Cc: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-01-06sunrpc: add sv_maxconn field to svc_serv (try #3)Jeff Layton
svc_check_conn_limits() attempts to prevent denial of service attacks by having the service close old connections once it reaches a threshold. This threshold is based on the number of threads in the service: (serv->sv_nrthreads + 3) * 20 Once we reach this, we drop the oldest connections and a printk pops to warn the admin that they should increase the number of threads. Increasing the number of threads isn't an option however for services like lockd. We don't want to eliminate this check entirely for such services but we need some way to increase this limit. This patch adds a sv_maxconn field to the svc_serv struct. When it's set to 0, we use the current method to calculate the max number of connections. RPC services can then set this on an as-needed basis. Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Neil Brown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-12-30Merge branch 'devel' into nextTrond Myklebust
2008-12-23rpc: pass target name down to rpc level on callbacksOlga Kornievskaia
The rpc client needs to know the principal that the setclientid was done as, so it can tell gssd who to authenticate to. Signed-off-by: Olga Kornievskaia <aglo@citi.umich.edu> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-12-23nfsd: pass client principal name in rsc downcallOlga Kornievskaia
Two principals are involved in krb5 authentication: the target, who we authenticate *to* (normally the name of the server, like nfs/server.citi.umich.edu@CITI.UMICH.EDU), and the source, we we authenticate *as* (normally a user, like bfields@UMICH.EDU) In the case of NFSv4 callbacks, the target of the callback should be the source of the client's setclientid call, and the source should be the nfs server's own principal. Therefore we allow svcgssd to pass down the name of the principal that just authenticated, so that on setclientid we can store that principal name with the new client, to be used later on callbacks. Signed-off-by: Olga Kornievskaia <aglo@citi.umich.edu> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-12-23rpc: add an rpc_pipe_open method\"J. Bruce Fields\
We want to transition to a new gssd upcall which is text-based and more easily extensible. To simplify upgrades, as well as testing and debugging, it will help if we can upgrade gssd (to a version which understands the new upcall) without having to choose at boot (or module-load) time whether we want the new or the old upcall. We will do this by providing two different pipes: one named, as currently, after the mechanism (normally "krb5"), and supporting the old upcall. One named "gssd" and supporting the new upcall version. We allow gssd to indicate which version it supports by its choice of which pipe to open. As we have no interest in supporting *simultaneous* use of both versions, we'll forbid opening both pipes at the same time. So, add a new pipe_open callback to the rpc_pipefs api, which the gss code can use to track which pipes have been open, and to refuse opens of incompatible pipes. We only need this to be called on the first open of a given pipe. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-12-23sunrpc: get rid of rpc_rqst.rq_bufsizeBenny Halevy
rq_bufsize is not used. Signed-off-by: Mike Sager <Mike.Sager@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-12-23SUNRPC: Remove the last remnant of the BKL...Trond Myklebust
Somehow, this escaped the previous purge. There should be no need to keep any extra locks in the XDR callbacks. The NFS client XDR code only writes into private objects, whereas all reads of shared objects are confined to fields that do not change, such as filehandles... Ditto for lockd, the NFSv2/v3 client mount code, and rpcbind. The nfsd XDR code may require the BKL, but since it does a synchronous RPC call from a thread that already holds the lock, that issue is moot. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-31misc: 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>
2008-10-28net: replace uses of NIP6_FMT with %p6Harvey Harrison
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-15Merge branch 'next'Trond Myklebust
2008-10-10RPC/RDMA: harden connection logic against missing/late rdma_cm upcalls.Tom Talpey
Add defensive timeouts to wait_for_completion() calls in RDMA address resolution, and make them interruptible. Fix the timeout units to milliseconds (formerly jiffies) and move to private header. Signed-off-by: Tom Talpey <talpey@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-10RPC/RDMA: add data types and new FRMR memory registration enum.Tom Talpey
Internal RPC/RDMA structure updates in preparation for FRMR support. Signed-off-by: Tom Talpey <talpey@netapp.com> Acked-by: Tom Tucker <tom@opengridcomputing.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-10-08Merge branch 'from-tomtucker' into for-2.6.28J. Bruce Fields
2008-10-06svcrdma: Modify the RPC recv path to use FRMR when availableTom Tucker
RPCRDMA requests that specify a read-list are fetched with RDMA_READ. Using an FRMR to map the data sink improves NFSRDMA security on transports that place the RDMA_READ data sink LKEY on the wire because the valid lifetime of the MR is only the duration of the RDMA_READ. The LKEY is invalidated when the last RDMA_READ WR completes. Mapping the data sink also allows for very large amounts to data to be fetched with a single WR, so if the client is also using FRMR, the entire RPC read-list can be fetched with a single WR. Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
2008-10-06svcrdma: Add a service to register a Fast Reg MR with the deviceTom Tucker
Fast Reg MR introduces a new WR type. Add a service to register the region with the adapter and update the completion handling to support completions with a NULL WR context. Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
2008-10-06svcrdma: Add FRMR get/put servicesTom Tucker
Add services for the allocating, freeing, and unmapping Fast Reg MR. These services will be used by the transport connection setup, send and receive routines. Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
2008-10-04NLM: Remove unused argument from svc_addsock() functionChuck Lever
Clean up: The svc_addsock() function no longer uses its "proto" argument, so remove it. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-10-03svcrdma: Add Fast Reg MR Data TypesTom Tucker
Add data types to track Fast Reg Memory Regions. The core data type is svc_rdma_fastreg_mr that associates a device MR with a host kva and page list. A field is added to the WR context to keep track of the FRMR used to map the local memory for an RPC. An FRMR list and spin lock are added to the transport instance to keep track of all FRMR allocated for the transport. Also added are device capability flags to indicate what the memory registration capabilities are for the underlying device and whether or not fast memory registration is supported. Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
2008-09-29nfsd: use nfs client rpc callback programBenny Halevy
since commit ff7d9756b501744540be65e172d27ee321d86103 "nfsd: use static memory for callback program and stats" do_probe_callback uses a static callback program (NFS4_CALLBACK) rather than the one set in clp->cl_callback.cb_prog as passed in by the client in setclientid (4.0) or create_session (4.1). This patches introduces rpc_create_args.prognumber that allows overriding program->number when creating rpc_clnt. Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29SUNRPC: Make svc_addr's argument a constantChuck Lever
Clean up: Add extra type safety and squelch a few compiler complaints in upcoming patches. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29SUNRPC: Support IPv6 when registering kernel RPC servicesChuck Lever
In order to advertise NFS-related services on IPv6 interfaces via rpcbind, the kernel RPC server implementation must use rpcb_v4_register() instead of rpcb_register(). A new kernel build option allows distributions to use the legacy v2 call until they integrate an appropriate user-space rpcbind daemon that can support IPv6 RPC services. I tried adding some automatic logic to fall back if registering with a v4 protocol request failed, but there are too many corner cases. So I just made it a compile-time switch that distributions can throw when they've replaced portmapper with rpcbind. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29SUNRPC: Simplify rpcb_register() APIChuck Lever
Bruce suggested there's no need to expose the difference between an error sending the PMAP_SET request and an error reply from the portmapper to rpcb_register's callers. The user space equivalent of rpcb_register() is pmap_set(3), which returns a bool_t : either the PMAP set worked, or it didn't. Simple. So let's remove the "*okay" argument from rpcb_register() and rpcb_v4_register(), and simply return an error if any part of the call didn't work. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29SUNRPC: Add address family field to svc_serv data structureChuck Lever
Introduce and initialize an address family field in the svc_serv structure. This field will determine what family to use for the service's listener sockets and what families are advertised via the local rpcbind daemon. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-08-13svcrdma: Fix race between svc_rdma_recvfrom thread and the dto_taskletTom Tucker
RDMA_READ completions are kept on a separate queue from the general I/O request queue. Since a separate lock is used to protect the RDMA_READ completion queue, a race exists between the dto_tasklet and the svc_rdma_recvfrom thread where the dto_tasklet sets the XPT_DATA bit and adds I/O to the read-completion queue. Concurrently, the recvfrom thread checks the generic queue, finds it empty and resets the XPT_DATA bit. A subsequent svc_xprt_enqueue will fail to enqueue the transport for I/O and cause the transport to "stall". The fix is to protect both lists with the same lock and set the XPT_DATA bit with this lock held. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-20Merge branch 'for-2.6.27' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
* 'for-2.6.27' of git://linux-nfs.org/~bfields/linux: (51 commits) nfsd: nfs4xdr.c do-while is not a compound statement nfsd: Use C99 initializers in fs/nfsd/nfs4xdr.c lockd: Pass "struct sockaddr *" to new failover-by-IP function lockd: get host reference in nlmsvc_create_block() instead of callers lockd: minor svclock.c style fixes lockd: eliminate duplicate nlmsvc_lookup_host call from nlmsvc_lock lockd: eliminate duplicate nlmsvc_lookup_host call from nlmsvc_testlock lockd: nlm_release_host() checks for NULL, caller needn't file lock: reorder struct file_lock to save space on 64 bit builds nfsd: take file and mnt write in nfs4_upgrade_open nfsd: document open share bit tracking nfsd: tabulate nfs4 xdr encoding functions nfsd: dprint operation names svcrdma: Change WR context get/put to use the kmem cache svcrdma: Create a kmem cache for the WR contexts svcrdma: Add flush_scheduled_work to module exit function svcrdma: Limit ORD based on client's advertised IRD svcrdma: Remove unused wait q from svcrdma_xprt structure svcrdma: Remove unneeded spin locks from __svc_rdma_free svcrdma: Add dma map count and WARN_ON ...
2008-07-18Merge branch 'master' of ↵David S. Miller
master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 Conflicts: Documentation/powerpc/booting-without-of.txt drivers/atm/Makefile drivers/net/fs_enet/fs_enet-main.c drivers/pci/pci-acpi.c net/8021q/vlan.c net/iucv/iucv.c
2008-07-15SUNRPC: Support registering IPv6 interfaces with local rpcbind daemonChuck Lever
Introduce a new API to register RPC services on IPv6 interfaces to allow the NFS server and lockd to advertise on IPv6 networks. Unlike rpcb_register(), the new rpcb_v4_register() function uses rpcbind protocol version 4 to contact the local rpcbind daemon. The version 4 SET/UNSET procedures allow services to register address families besides AF_INET, register at specific network interfaces, and register transport protocols besides UDP and TCP. All of this functionality is exposed via the new rpcb_v4_register() kernel API. A user-space rpcbind daemon implementation that supports version 4 of the rpcbind protocol is required in order to make use of this new API. Note that rpcbind version 3 is sufficient to support the new rpcbind facilities listed above, but most extant implementations use version 4. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09rpc: minor cleanup of scheduler callback code\\\"J. Bruce Fields\\\
Try to make the comment here a little more clear and concise. Also, this macro definition seems unnecessary. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09rpc: bring back cl_chattyOlga Kornievskaia
The cl_chatty flag alows us to control whether a given rpc client leaves "server X not responding, timed out" messages in the syslog. Such messages make sense for ordinary nfs clients (where an unresponsive server means applications on the mountpoint are probably hanging), but not for the callback client (which can fail more commonly, with the only result just of disabling some optimizations). Previously cl_chatty was removed, do to lack of users; reinstate it, and use it for the nfsd's callback client. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-03Merge branch 'for-bfields' of git://linux-nfs.org/~tomtucker/xprt-switch-2.6 ↵J. Bruce Fields
into for-2.6.27
2008-07-02svcrdma: Change WR context get/put to use the kmem cacheTom Tucker
Change the WR context pool to be shared across mount points. This reduces the RDMA transport memory footprint significantly since idle mounts don't consume WR context memory. Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
2008-07-02svcrdma: Remove unused wait q from svcrdma_xprt structureTom Tucker
The sc_read_wait queue head is no longer used. Remove it. Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
2008-07-02svcrdma: Add dma map count and WARN_ONTom Tucker
Add a dma map count in order to verify that all DMA mapping resources have been freed when the transport is closed. Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
2008-07-02svcrdma: Use reply and chunk map for RDMA_READ processingTom Tucker
Modify the RDMA_READ processing to use the reply and chunk list mapping data types. Also add a special purpose 'hdr_count' field in in the context to hold the header page count instead of overloading the SGE length field and corrupting the DMA map length. Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
2008-07-02svcrdma: Add a type for keeping NFS RPC mappingTom Tucker
Create a new data structure to hold the remote client address space to local server address space mapping. Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
2008-06-23gss_krb5: create a define for token header size and clean up ptr locationKevin Coffman
cleanup: Document token header size with a #define instead of open-coding it. Don't needlessly increment "ptr" past the beginning of the header which makes the values passed to functions more understandable and eliminates the need for extra "krb5_hdr" pointer. Clean up some intersecting white-space issues flagged by checkpatch.pl. This leaves the checksum length hard-coded at 8 for DES. A later patch cleans that up. Signed-off-by: Kevin Coffman <kwc@citi.umich.edu> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-23sunrpc: remove sv_kill_signal field from svc_serv structJeff Layton
Since we no longer make any distinction between shutdown signals with nfsd, then it becomes easier to just standardize on a particular signal to use to bring it down (SIGINT, in this case). Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-23knfsd: convert knfsd to kthread APIJeff Layton
This patch is rather large, but I couldn't figure out a way to break it up that would remain bisectable. It does several things: - change svc_thread_fn typedef to better match what kthread_create expects - change svc_pool_map_set_cpumask to be more kthread friendly. Make it take a task arg and and get rid of the "oldmask" - have svc_set_num_threads call kthread_create directly - eliminate __svc_create_thread Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-11net: remove CVS keywordsAdrian Bunk
This patch removes CVS keywords that weren't updated for a long time from comments. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-05-19svcrdma: Change svc_rdma_send_error return type to voidTom Tucker
The svc_rdma_send_error function is called when an RPCRDMA protocol error is detected. This function attempts to post an error reply message. Since an error posting to a transport in error is ignored, change the return type to void. Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
2008-05-19svcrdma: Move destroy to kernel threadTom Tucker
Some providers may wait while destroying adapter resources. Since it is possible that the last reference is put on the dto_tasklet, the actual destroy must be scheduled as a work item. Signed-off-by: Tom Tucker <tom@opengridcomputing.com>