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2024-07-08nfs: move nfs_wait_on_request to write.cChristoph Hellwig
nfs_wait_on_request is now only used in write.c. Move it there and mark it static. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2024-07-08nfs: fold nfs_page_group_lock_subrequests into nfs_lock_and_join_requestsChristoph Hellwig
Fold nfs_page_group_lock_subrequests into nfs_lock_and_join_requests to prepare for future changes to this code, and move the helpers to write.c as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2024-07-08nfs: simplify nfs_folio_find_and_lock_requestChristoph Hellwig
nfs_folio_find_and_lock_request and the nfs_page_group_lock_head helper called by it spend quite some effort to deal with head vs subrequests. But given that only the head request can be stashed in the folio private data, non of that is required. Fold the locking logic from nfs_page_group_lock_head into nfs_folio_find_and_lock_request and simplify the result based on the invariant that we always find the head request in the folio private data. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2024-07-08nfs: remove dead code for the old swap over NFS implementationChristoph Hellwig
Remove the code testing folio_test_swapcache either explicitly or implicitly in pagemap.h headers, as is now handled using the direct I/O path and not the buffered I/O path that these helpers are located in. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2024-05-24nfs: Avoid flushing many pages with NFS_FILE_SYNCJan Kara
When we are doing WB_SYNC_ALL writeback, nfs submits write requests with NFS_FILE_SYNC flag to the server (which then generally treats it as an O_SYNC write). This helps to reduce latency for single requests but when submitting more requests, additional fsyncs on the server side hurt latency. NFS generally avoids this additional overhead by not setting NFS_FILE_SYNC if desc->pg_moreio is set. However this logic doesn't always work. When we do random 4k writes to a huge file and then call fsync(2), each page writeback is going to be sent with NFS_FILE_SYNC because after preparing one page for writeback, we start writing back next, nfs_do_writepage() will call nfs_pageio_cond_complete() which finds the page is not contiguous with previously prepared IO and submits is *without* setting desc->pg_moreio. Hence NFS_FILE_SYNC is used resulting in poor performance. Fix the problem by setting desc->pg_moreio in nfs_pageio_cond_complete() before submitting outstanding IO. This improves throughput of fsync-after-random-writes on my test SSD from ~70MB/s to ~250MB/s. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2023-04-11NFS: Convert buffered read paths to use netfs when fscache is enabledDave Wysochanski
Convert the NFS buffered read code paths to corresponding netfs APIs, but only when fscache is configured and enabled. The netfs API defines struct netfs_request_ops which must be filled in by the network filesystem. For NFS, we only need to define 5 of the functions, the main one being the issue_read() function. The issue_read() function is called by the netfs layer when a read cannot be fulfilled locally, and must be sent to the server (either the cache is not active, or it is active but the data is not available). Once the read from the server is complete, netfs requires a call to netfs_subreq_terminated() which conveys either how many bytes were read successfully, or an error. Note that issue_read() is called with a structure, netfs_io_subrequest, which defines the IO requested, and contains a start and a length (both in bytes), and assumes the underlying netfs will return a either an error on the whole region, or the number of bytes successfully read. The NFS IO path is page based and the main APIs are the pgio APIs defined in pagelist.c. For the pgio APIs, there is no way for the caller to know how many RPCs will be sent and how the pages will be broken up into underlying RPCs, each of which will have their own completion and return code. In contrast, netfs is subrequest based, a single subrequest may contain multiple pages, and a single subrequest is initiated with issue_read() and terminated with netfs_subreq_terminated(). Thus, to utilze the netfs APIs, NFS needs some way to accommodate the netfs API requirement on the single response to the whole subrequest, while also minimizing disruptive changes to the NFS pgio layer. The approach taken with this patch is to allocate a small structure for each nfs_netfs_issue_read() call, store the final error and number of bytes successfully transferred in the structure, and update these values as each RPC completes. The refcount on the structure is used as a marker for the last RPC completion, is incremented in nfs_netfs_read_initiate(), and decremented inside nfs_netfs_read_completion(), when a nfs_pgio_header contains a valid pointer to the data. On the final put (which signals the final outstanding RPC is complete) in nfs_netfs_read_completion(), call netfs_subreq_terminated() with either the final error value (if one or more READs complete with an error) or the number of bytes successfully transferred (if all RPCs complete successfully). Note that when all RPCs complete successfully, the number of bytes transferred is capped to the length of the subrequest. Capping the transferred length to the subrequest length prevents "Subreq overread" warnings from netfs. This is due to the "aligned_len" in nfs_pageio_add_page(), and the corner case where NFS requests a full page at the end of the file, even when i_size reflects only a partial page (NFS overread). Signed-off-by: Dave Wysochanski <dwysocha@redhat.com> Tested-by: Daire Byrne <daire@dneg.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2023-02-22Merge tag 'nfs-for-6.3-1' of git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds
Pull NFS client updates from Anna Schumaker: "New Features: - Convert the read and write paths to use folios Bugfixes and Cleanups: - Fix tracepoint state manager flag printing - Fix disabling swap files - Fix NFSv4 client identifier sysfs path in the documentation - Don't clear NFS_CAP_COPY if server returns NFS4ERR_OFFLOAD_DENIED - Treat GETDEVICEINFO errors as a layout failure - Replace kmap_atomic() calls with kmap_local_page() - Constify sunrpc sysfs kobj_type structures" * tag 'nfs-for-6.3-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (25 commits) fs/nfs: Replace kmap_atomic() with kmap_local_page() in dir.c pNFS/filelayout: treat GETDEVICEINFO errors as layout failure Documentation: Fix sysfs path for the NFSv4 client identifier nfs42: do not fail with EIO if ssc returns NFS4ERR_OFFLOAD_DENIED NFS: fix disabling of swap SUNRPC: make kobj_type structures constant nfs4trace: fix state manager flag printing NFS: Remove unnecessary check in nfs_read_folio() NFS: Improve tracing of nfs_wb_folio() NFS: Enable tracing of nfs_invalidate_folio() and nfs_launder_folio() NFS: fix up nfs_release_folio() to try to release the page NFS: Clean up O_DIRECT request allocation NFS: Fix up nfs_vm_page_mkwrite() for folios NFS: Convert nfs_write_begin/end to use folios NFS: Remove unused function nfs_wb_page() NFS: Convert buffered writes to use folios NFS: Convert the function nfs_wb_page() to use folios NFS: Convert buffered reads to use folios NFS: Add a helper nfs_wb_folio() NFS: Convert the remaining pagelist helper functions to support folios ...
2023-02-14NFS: Clean up O_DIRECT request allocationTrond Myklebust
Rather than adjusting the index+offset after the call to nfs_create_request(), add a function nfs_page_create_from_page() that takes an offset. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2023-02-14NFS: Convert buffered reads to use foliosTrond Myklebust
Perform a largely mechanical conversion of references to struct page and page-specific functions to use the folio equivalents. Note that the fscache functionality remains untouched. Instead we just pass in the folio page. This should be OK, as long as we use order 0 folios together with fscache. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2023-02-14NFS: Convert the remaining pagelist helper functions to support foliosTrond Myklebust
Allow creation of subrequests from a request that is carrying a folio. Add helpers to set up and tear down requests carrying folios. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2023-02-14NFS: Add a helper to convert a struct nfs_page into an inodeTrond Myklebust
Replace all the open coded calls to page_file_mapping(req->wb_page)->host. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2023-02-14NFS: Fix nfs_coalesce_size() to work with foliosTrond Myklebust
Use the helper folio_size() where appropriate. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2023-02-14NFS: Support folios in nfs_generic_pgio()Trond Myklebust
Add support for multi-page folios in the generic NFS i/o engine. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2023-02-14NFS: Add basic functionality for tracking folios in struct nfs_pageTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2023-02-14NFS: Fix for xfstests generic/208Trond Myklebust
If the same page and data is being used for multiple requests, then ignore that when the request indicates we're reading from the start of the page. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2023-01-11filelock: move file locking definitions to separate header fileJeff Layton
The file locking definitions have lived in fs.h since the dawn of time, but they are only used by a small subset of the source files that include it. Move the file locking definitions to a new header file, and add the appropriate #include directives to the source files that need them. By doing this we trim down fs.h a bit and limit the amount of rebuilding that has to be done when we make changes to the file locking APIs. Reviewed-by: Xiubo Li <xiubli@redhat.com> Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Howells <dhowells@redhat.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Acked-by: Chuck Lever <chuck.lever@oracle.com> Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com> Acked-by: Steve French <stfrench@microsoft.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2022-11-30nfs: use locks_inode_context helperJeff Layton
nfs currently doesn't access i_flctx safely. This requires a smp_load_acquire, as the pointer is set via cmpxchg (a release operation). Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Anna Schumaker <anna@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2022-05-31NFSv4.1 mark qualified async operations as MOVEABLE tasksOlga Kornievskaia
Mark async operations such as RENAME, REMOVE, COMMIT MOVEABLE for the nfsv4.1+ sessions. Fixes: 85e39feead948 ("NFSv4.1 identify and mark RPC tasks that can move between transports") Signed-off-by: Olga Kornievskaia <kolga@netapp.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2022-03-25NFS: Don't loop forever in nfs_do_recoalesce()Trond Myklebust
If __nfs_pageio_add_request() fails to add the request, it will return with either desc->pg_error < 0, or mirror->pg_recoalesce will be set, so we are guaranteed either to exit the function altogether, or to loop. However if there is nothing left in mirror->pg_list to coalesce, we must exit, so make sure that we clear mirror->pg_recoalesce every time we loop. Reported-by: Olga Kornievskaia <aglo@umich.edu> Fixes: 70536bf4eb07 ("NFS: Clean up reset of the mirror accounting variables") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-22NFS: Avoid writeback threads getting stuck in mempool_alloc()Trond Myklebust
In a low memory situation, allow the NFS writeback code to fail without getting stuck in infinite loops in mempool_alloc(). Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-10-20SUNRPC: Trace calls to .rpc_call_doneChuck Lever
Introduce a single tracepoint that can replace simple dprintk call sites in upper layer "rpc_call_done" callbacks. Example: kworker/u24:2-1254 [001] 771.026677: rpc_stats_latency: task:00000001@00000002 xid=0x16a6f3c0 rpcbindv2 GETPORT backlog=446 rtt=101 execute=555 kworker/u24:2-1254 [001] 771.026677: rpc_task_call_done: task:00000001@00000002 flags=ASYNC|DYNAMIC|SOFT|SOFTCONN|SENT runstate=RUNNING|ACTIVE status=0 action=rpcb_getport_done kworker/u24:2-1254 [001] 771.026678: rpcb_setport: task:00000001@00000002 status=0 port=20048 Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-10-03NFS: Fix a few more clear_bit() instances that need release semanticsTrond Myklebust
All these bits are being used as bit locks. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-07-08NFSv4.1 identify and mark RPC tasks that can move between transportsOlga Kornievskaia
In preparation for when we can re-try a task on a different transport, identify and mark such RPC tasks as moveable. Only 4.1+ operarations can be re-tried on a different transport. Signed-off-by: Olga Kornievskaia <kolga@netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-05-26NFS: Clean up reset of the mirror accounting variablesTrond Myklebust
Now that nfs_pageio_do_add_request() resets the pg_count, we don't need these other inlined resets. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-05-26NFS: Don't corrupt the value of pg_bytes_written in nfs_do_recoalesce()Trond Myklebust
The value of mirror->pg_bytes_written should only be updated after a successful attempt to flush out the requests on the list. Fixes: a7d42ddb3099 ("nfs: add mirroring support to pgio layer") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-05-26NFS: Fix an Oopsable condition in __nfs_pageio_add_request()Trond Myklebust
Ensure that nfs_pageio_error_cleanup() resets the mirror array contents, so that the structure reflects the fact that it is now empty. Also change the test in nfs_pageio_do_add_request() to be more robust by checking whether or not the list is empty rather than relying on the value of pg_count. Fixes: a7d42ddb3099 ("nfs: add mirroring support to pgio layer") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-04-05NFS: Fix up incorrect documentationTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-11-30pNFS/flexfiles: Fix array overflow when flexfiles mirroring is enabledTrond Myklebust
If the flexfiles mirroring is enabled, then the read code expects to be able to set pgio->pg_mirror_idx to point to the data server that is being used for this particular read. However it does not change the pg_mirror_count because we only need to send a single read. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-08-23treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-06-11NFS: Add a tracepoint in nfs_set_pgio_error()Chuck Lever
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-05-13NFS/pnfs: Don't use RPC_TASK_CRED_NOREF with pnfsTrond Myklebust
When we're doing pnfs then the credential being used for the RPC call is not necessarily the same as the one used in the open context, so don't use RPC_TASK_CRED_NOREF. Fixes: 612965072020 ("NFSv4: Avoid referencing the cred unnecessarily during NFSv4 I/O") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-01NFS: Refactor nfs_lock_and_join_requests()Trond Myklebust
Refactor nfs_lock_and_join_requests() in order to separate out the subrequest merging into its own function nfs_lock_and_join_group() that can be used by O_DIRECT. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-01NFS: Reverse the submission order of requests in __nfs_pageio_add_request()Trond Myklebust
If we have to split the request up into subrequests, we have to submit the request pointed to by the function call parameter last, in case there is an error or other issue that causes us to exit before the last request is submitted. The reason is that the caller is expected to perform cleanup in those cases. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-01NFS: Clean up nfs_lock_and_join_requests()Trond Myklebust
Clean up nfs_lock_and_join_requests() to simplify the calculation of the range covered by the page group, taking into account the presence of mirrors. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-01NFS: Remove the redundant function nfs_pgio_has_mirroring()Trond Myklebust
We need to trust that desc->pg_mirror_idx is set correctly, whether or not mirroring is enabled. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-01NFS: Fix memory leaks in nfs_pageio_stop_mirroring()Trond Myklebust
If we just set the mirror count to 1 without first clearing out the mirrors, we can leak queued up requests. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-01NFS: Fix use-after-free issues in nfs_pageio_add_request()Trond Myklebust
We need to ensure that we create the mirror requests before calling nfs_pageio_add_request_mirror() on the request we are adding. Otherwise, we can end up with a use-after-free if the call to nfs_pageio_add_request_mirror() triggers I/O. Fixes: c917cfaf9bbe ("NFS: Fix up NFS I/O subrequest creation") Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-04-01NFS: Fix races nfs_page_group_destroy() vs nfs_destroy_unlinked_subrequests()Trond Myklebust
When a subrequest is being detached from the subgroup, we want to ensure that it is not holding the group lock, or in the process of waiting for the group lock. Fixes: 5b2b5187fa85 ("NFS: Fix nfs_page_group_destroy() and nfs_lock_and_join_requests() race cases") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-28NFS: Remove unused FLUSH_SYNC support in nfs_initiate_pgio()Trond Myklebust
If the FLUSH_SYNC flag is set, nfs_initiate_pgio() will currently wait for completion, and then return the status of the I/O operation. What we actually want to report in nfs_pageio_doio() is whether or not the RPC call was launched successfully, whereas actual I/O status is intended handled in the reply callbacks. Since FLUSH_SYNC is never set by any of the callers anyway, let's just remove that code altogether. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-16NFS: Assume cred is pinned by open context in I/O requestsTrond Myklebust
In read/write/commit, we should be able to assume that the cred is pinned by the open context. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-08-19NFS: Fix initialisation of I/O result struct in nfs_pgio_rpcsetupTrond Myklebust
Initialise the result count to 0 rather than initialising it to the argument count. The reason is that we want to ensure we record the I/O stats correctly in the case where an error is returned (for instance in the layoutstats). Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-08-19NFS: Ensure O_DIRECT reports an error if the bytes read/written is 0Trond Myklebust
If the attempt to resend the I/O results in no bytes being read/written, we must ensure that we report the error. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Fixes: 0a00b77b331a ("nfs: mirroring support for direct io") Cc: stable@vger.kernel.org # v3.20+
2019-08-19NFSv4/pnfs: Fix a page lock leak in nfs_pageio_resend()Trond Myklebust
If the attempt to resend the pages fails, we need to ensure that we clean up those pages that were not transmitted. Fixes: d600ad1f2bdb ("NFS41: pop some layoutget errors to application") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: stable@vger.kernel.org # v4.5+
2019-07-06NFS: Clean up writeback codeTrond Myklebust
Now that the VM promises never to recurse back into the filesystem layer on writeback, remove all the GFP_NOFS references etc from the generic writeback code. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-05-21treewide: Add SPDX license identifier for missed filesThomas Gleixner
Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25NFS: Remove redundant open context from nfs_pageTrond Myklebust
The lock context already references and tracks the open context, so take the opportunity to save some space in struct nfs_page. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-04-25NFS: Add a helper to return a pointer to the open context of a struct nfs_pageTrond Myklebust
Add a helper for when we remove the explicit pointer to the open context. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-04-25pNFS: Add tracking to limit the number of pNFS retriesTrond Myklebust
When the client is reading or writing using pNFS, and hits an error on the DS, then it typically sends a LAYOUTERROR and/or LAYOUTRETURN to the MDS, before redirtying the failed pages, and going for a new round of reads/writebacks. The problem is that if the server has no way to fix the DS, then we may need a way to interrupt this loop after a set number of attempts have been made. This patch adds an optional module parameter that allows the admin to specify how many times to retry the read/writeback process before failing with a fatal error. The default behaviour is to retry forever. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-04-25NFS: Remove unused argument from nfs_create_request()Trond Myklebust
All the callers of nfs_create_request() are now creating page group heads, so we can remove the redundant 'last' page argument. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-04-25NFS: Fix up NFS I/O subrequest creationTrond Myklebust
We require all NFS I/O subrequests to duplicate the lock context as well as the open context. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>