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* NFS: Avoid memcpy() run-time warning for struct sockaddr overflowsKees Cook2022-10-271-3/+4
| | | | | | | | | | | | | | | | | | | | | | | The 'nfs_server' and 'mount_server' structures include a union of 'struct sockaddr' (with the older 16 bytes max address size) and 'struct sockaddr_storage' which is large enough to hold all the supported sa_family types (128 bytes max size). The runtime memcpy() buffer overflow checker is seeing attempts to write beyond the 16 bytes as an overflow, but the actual expected size is that of 'struct sockaddr_storage'. Plumb the use of 'struct sockaddr_storage' more completely through-out NFS, which results in adjusting the memcpy() buffers to the correct union members. Avoids this false positive run-time warning under CONFIG_FORTIFY_SOURCE: memcpy: detected field-spanning write (size 28) of single field "&ctx->nfs_server.address" at fs/nfs/namespace.c:178 (size 16) Reported-by: kernel test robot <yujie.liu@intel.com> Link: https://lore.kernel.org/all/202210110948.26b43120-yujie.liu@intel.com Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Anna Schumaker <anna@kernel.org> Cc: linux-nfs@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* NFS: remove duplicate headersChen Zhou2020-05-271-1/+0
| | | | | | | Remove duplicate headers which are included twice. Signed-off-by: Chen Zhou <chenzhou10@huawei.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* nfsd: export upcalls must not return ESTALE when mountd is downTrond Myklebust2020-03-161-5/+6
| | | | | | | | | | If the rpc.mountd daemon goes down, then that should not cause all exports to start failing with ESTALE errors. Let's explicitly distinguish between the cache upcall cases that need to time out, and those that do not. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
* NFS: Replace various occurrences of kstrndup() with kmemdup_nul()Trond Myklebust2020-02-031-1/+1
| | | | | | | | | When we already know the string length, it is more efficient to use kmemdup_nul(). Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> [Anna - Changes to super.c were already made during fscontext conversion] Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* keys: Pass the network namespace into request_key mechanismDavid Howells2019-06-271-1/+2
| | | | | | | | | | | | Create a request_key_net() function and use it to pass the network namespace domain tag into DNS revolver keys and rxrpc/AFS keys so that keys for different domains can coexist in the same keyring. Signed-off-by: David Howells <dhowells@redhat.com> cc: netdev@vger.kernel.org cc: linux-nfs@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: linux-afs@lists.infradead.org
* dns_resolver: Allow used keys to be invalidatedDavid Howells2019-05-151-1/+1
| | | | | | | | | | | | | Allow used DNS resolver keys to be invalidated after use if the caller is doing its own caching of the results. This reduces the amount of resources required. Fix AFS to invalidate DNS results to kill off permanent failure records that get lodged in the resolver keyring and prevent future lookups from happening. Fixes: 0a5143f2f89c ("afs: Implement VL server rotation") Signed-off-by: David Howells <dhowells@redhat.com>
* NFS: Fix up a typo in nfs_dns_ent_putTrond Myklebust2018-10-291-1/+1
| | | | | | | | call_rcu() needs to take a first argument of type (struct rcu_head *). Fixes: fd497f1e40d9 ("NFS: Lockless DNS lookups") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* NFS: Lockless DNS lookupsTrond Myklebust2018-10-291-3/+12
| | | | | | | Enable RCU protected lookup in the legacy DNS resolver. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* NFS: Enabling v4.2 should not recompile nfsd and lockdAnna Schumaker2013-11-191-0/+2
| | | | | | | | | When CONFIG_NFS_V4_2 is toggled nfsd and lockd will be recompiled, instead of only the nfs client. This patch moves a small amount of code into the client directory to avoid unnecessary recompiles. Signed-off-by: Anna Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFSv4: Move the DNS resolver into the NFSv4 moduleTrond Myklebust2013-06-181-3/+29
| | | | | | | | | | The other protocols don't use it, so make it local to NFSv4, and remove the EXPORT. Also ensure that we only compile in cache_lib.o if we're using the legacy DNS resolver. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Bryan Schumaker <bjschuma@netapp.com>
* SUNRPC: remove "cache_request" argument in sunrpc_cache_pipe_upcall() functionStanislav Kinsbursky2013-02-151-1/+1
| | | | | | | | Passing this pointer is redundant since it's stored on cache_detail structure, which is also passed to sunrpc_cache_pipe_upcall () function. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* SUNRPC: introduce cache_detail->cache_request callbackStanislav Kinsbursky2013-02-151-1/+2
| | | | | | | | This callback will allow to simplify upcalls in further patches in this series. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* NFS: simplify and clean cache libraryStanislav Kinsbursky2013-02-151-5/+1
| | | | | | | | | | | | | This is a cleanup patch. Such helpers like nfs_cache_init() and nfs_cache_destroy() are redundant, because they are just a wrappers around sunrpc_init_cache_detail() and sunrpc_destroy_cache_detail() respectively. So let's remove them completely and move corresponding logic to nfs_cache_register_net() and nfs_cache_unregister_net() respectively (since they are called together anyway). Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* NFS: use SUNRPC cache creation and destruction helper for DNS cacheStanislav Kinsbursky2013-02-151-35/+25
| | | | | | | | | | This cache was the first containerized and doesn't use net-aware cache creation and destruction helpers. This is a cleanup patch which just makes code looks clearer and reduce amount of lines of code. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* sunrpc: move address copy/cmp/convert routines and prototypes from clnt.h to ↵Jeff Layton2013-02-051-0/+2
| | | | | | | | | | | addr.h These routines are used by server and client code, so having them in a separate header would be best. Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* NFS: fix bug in legacy DNS resolver.NeilBrown2012-10-311-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | The DNS resolver's use of the sunrpc cache involves a 'ttl' number (relative) rather that a timeout (absolute). This confused me when I wrote commit c5b29f885afe890f953f7f23424045cdad31d3e4 "sunrpc: use seconds since boot in expiry cache" and I managed to break it. The effect is that any TTL is interpreted as 0, and nothing useful gets into the cache. This patch removes the use of get_expiry() - which really expects an expiry time - and uses get_uint() instead, treating the int correctly as a ttl. This fixes a regression that has been present since 2.6.37, causing certain NFS accesses in certain environments to incorrectly fail. Reported-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Chuck Lever <chuck.lever@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Convert v4 into a moduleBryan Schumaker2012-07-301-0/+4
| | | | | | | | | | | | This patch exports symbols needed by the v4 module. In addition, I also switch over to using IS_ENABLED() to check if CONFIG_NFS_V4 or CONFIG_NFS_V4_MODULE are set. The module (nfs4.ko) will be created in the same directory as nfs.ko and will be automatically loaded the first time you try to mount over NFS v4. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Fix a number of sparse warningsTrond Myklebust2012-03-111-0/+1
| | | | | | | | | | | | | Fix a number of "warning: symbol 'foo' was not declared. Should it be static?" conditions. Fix 2 cases of "warning: Using plain integer as NULL pointer" fs/nfs/delegation.c:263:31: warning: restricted fmode_t degrades to integer - We want to allow upgrades to a WRITE delegation, but should otherwise consider servers that hand out duplicate delegations to be borken. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: pass proper net rpc_pton() in nfs_dns_resolve_name()Stanislav Kinsbursky2012-02-061-1/+1
| | | | | Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: parse DNS cache in proper network namespace contextStanislav Kinsbursky2012-01-311-1/+1
| | | | | | | This patch replaces "init_net" with cache's owner net in rpc_pton() call. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* SUNRPC: parametrize rpc_pton() by network contextStanislav Kinsbursky2012-01-311-2/+2
| | | | | | | | 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>
* NFS: DNS resolver PipeFS notifier introducedStanislav Kinsbursky2012-01-311-1/+37
| | | | | | | | | | | | This patch subscribes DNS resolver caches to RPC pipefs notifications. Notifier is registering on NFS module load. This notifier callback is responsible for creation/destruction of PipeFS DNS resolver cache directory. 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>
* NFS: DNS resolver cache per network namespace context introducedStanislav Kinsbursky2012-01-311-33/+63
| | | | | | | | | | | | | | | | | | | This patch implements DNS resolver cache creation and registration for each alive network namespace context. This was done by registering NFS per-net operations, responsible for DNS cache allocation/register and unregister/destructioning instead of initialization and destruction of static "nfs_dns_resolve" cache detail (this one was removed). Pointer to network dns resolver cache is stored in new per-net "nfs_net" structure. This patch also changes nfs_dns_resolve_name() function prototype (and it's calls) by adding network pointer parameter, which is used to get proper DNS resolver cache pointer for do_cache_lookup_wait() call. Note: empty nfs_dns_resolver_init() and nfs_dns_resolver_destroy() functions will be used in next patch in the series. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: handle NFS caches dentries by network namespace aware routinesStanislav Kinsbursky2012-01-311-2/+2
| | | | | | | | This patch makes NFS caches PipeFS dentries allocated and destroyed in network namespace context by PipeFS network namespace aware routines. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: split cache creation and PipeFS registrationStanislav Kinsbursky2012-01-311-1/+10
| | | | | | | | | | This precursor patch splits NFS 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>
* sunrpc: use seconds since boot in expiry cacheNeilBrown2010-09-071-3/+3
| | | | | | | | | | | | This protects us from confusion when the wallclock time changes. We convert to and from wallclock when setting or reading expiry times. Also use seconds since boot for last_clost time. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* NFS: Use kernel DNS resolver [ver #2]Bryan Schumaker2010-08-111-0/+24
| | | | | | | | | | | Use the kernel DNS resolver to translate hostnames to IP addresses. Create a new config option to choose between the legacy DNS resolver and the new resolver. Signed-off-by: Bryan Schumaker <bjschuma@netapp.com> Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* NFS: Fix an allocation-under-spinlock bugTrond Myklebust2010-03-021-3/+15
| | | | | | | | sunrpc_cache_update() will always call detail->update() from inside the detail->hash_lock, so it cannot allocate memory. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: stable@kernel.org
* NFSv4: Ensure nfs_dns_lookup() and nfs_dns_update() are declared staticTrond Myklebust2009-12-031-2/+2
| | | | | | Fix two 'sparse' warnings in fs/nfs/dns_resolve.c Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* NFS: Add a dns resolver for use with NFSv4 referrals and migrationTrond Myklebust2009-08-191-0/+335
The NFSv4 and NFSv4.1 protocols both allow for the redirection of a client from one server to another in order to support filesystem migration and replication. For full protocol support, we need to add the ability to convert a DNS host name into an IP address that we can feed to the RPC client. We'll reuse the sunrpc cache, now that it has been converted to work with rpc_pipefs. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>