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2022-02-28SUNRPC: Rename svc_close_xprt()Chuck Lever1-1/+1
Clean up: Use the "svc_xprt_<task>" function naming convention as is used for other external APIs. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-22svcrdma: Normalize Send page handlingChuck Lever1-1/+7
Currently svc_rdma_sendto() migrates xdr_buf pages into a separate page list and NULLs out a bunch of entries in rq_pages while the pages are under I/O. The Send completion handler then frees those pages later. Instead, let's wait for the Send completion, then handle page releasing in the nfsd thread. I'd like to avoid the cost of 250+ put_page() calls in the Send completion handler, which is single- threaded. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-07svcrdma: disable timeouts on rdma backchannelTimo Rothenpieler1-3/+3
This brings it in line with the regular tcp backchannel, which also has all those timeouts disabled. Prevents the backchannel from timing out, getting some async operations like server side copying getting stuck indefinitely on the client side. Signed-off-by: Timo Rothenpieler <timo@rothenpieler.org> Fixes: 5d252f90a800 ("svcrdma: Add class for RDMA backwards direction transport") Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-02-05rpcrdma: Fix comments about reverse-direction operationChuck Lever1-2/+2
During the final stages of publication of RFC 8167, reviewers requested that we use the term "reverse direction" rather than "backwards direction". Update comments to reflect this preference. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Tom Talpey <tom@talpey.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2020-11-30svcrdma: Support multiple write chunks when pulling upChuck Lever1-4/+10
When counting the number of SGEs needed to construct a Send request, do not count result payloads. And, when copying the Reply message into the pull-up buffer, result payloads are not to be copied to the Send buffer. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-14svcrdma: Record send_ctxt completion ID in trace_svcrdma_post_send()Chuck Lever1-1/+1
First, refactor: Dereference the svc_rdma_send_ctxt inside svc_rdma_send() instead of at every call site. Then, it can be passed into trace_svcrdma_post_send() to get the proper completion ID. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-05-18svcrdma: Remove backchannel dprintk call sitesChuck Lever1-43/+5
Clean up. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-05-18svcrdma: Fix backchannel return codeChuck Lever1-28/+10
Way back when I was writing the RPC/RDMA server-side backchannel code, I misread the TCP backchannel reply handler logic. When svc_tcp_recvfrom() successfully receives a backchannel reply, it does not return -EAGAIN. It sets XPT_DATA and returns zero. Update svc_rdma_recvfrom() to return zero. Here, XPT_DATA doesn't need to be set again: it is set whenever a new message is received, behind a spin lock in a single threaded context. Also, if handling the cb reply is not successful, the message is simply dropped. There's no special message framing to deal with as there is in the TCP case. Now that the handle_bc_reply() return value is ignored, I've removed the dprintk call sites in the error exit of handle_bc_reply() in favor of trace points in other areas that already report the error cases. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-05-18SUNRPC: Move xpt_mutex into socket xpo_sendto methodsChuck Lever1-19/+16
It appears that the RPC/RDMA transport does not need serialization of calls to its xpo_sendto method. Move the mutex into the socket methods that still need that serialization. Tail latencies are unambiguously better with this patch applied. fio randrw 8KB 70/30 on NFSv3, smaller numbers are better: clat percentiles (usec): With xpt_mutex: r | 99.99th=[ 8848] w | 99.99th=[ 9634] Without xpt_mutex: r | 99.99th=[ 8586] w | 99.99th=[ 8979] Serializing the construction of RPC/RDMA transport headers is not really necessary at this point, because the Linux NFS server implementation never changes its credit grant on a connection. If that should change, then svc_rdma_sendto will need to serialize access to the transport's credit grant fields. Reported-by: kbuild test robot <lkp@intel.com> [ cel: fix uninitialized variable warning ] Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-04-17SUNRPC: Fix backchannel RPC soft lockupsChuck Lever1-0/+2
Currently, after the forward channel connection goes away, backchannel operations are causing soft lockups on the server because call_transmit_status's SOFTCONN logic ignores ENOTCONN. Such backchannel Calls are aggressively retried until the client reconnects. Backchannel Calls should use RPC_TASK_NOCONNECT rather than RPC_TASK_SOFTCONN. If there is no forward connection, the server is not capable of establishing a connection back to the client, thus that backchannel request should fail before the server attempts to send it. Commit 58255a4e3ce5 ("NFSD: NFSv4 callback client should use RPC_TASK_SOFTCONN") was merged several years before RPC_TASK_NOCONNECT was available. Because setup_callback_client() explicitly sets NOPING, the NFSv4.0 callback connection depends on the first callback RPC to initiate a connection to the client. Thus NFSv4.0 needs to continue to use RPC_TASK_SOFTCONN. Suggested-by: Trond Myklebust <trondmy@hammerspace.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Cc: <stable@vger.kernel.org> # v4.20+
2020-03-27svcrdma: Fix leak of transport addressesChuck Lever1-0/+1
Kernel memory leak detected: unreferenced object 0xffff888849cdf480 (size 8): comm "kworker/u8:3", pid 2086, jiffies 4297898756 (age 4269.856s) hex dump (first 8 bytes): 30 00 cd 49 88 88 ff ff 0..I.... backtrace: [<00000000acfc370b>] __kmalloc_track_caller+0x137/0x183 [<00000000a2724354>] kstrdup+0x2b/0x43 [<0000000082964f84>] xprt_rdma_format_addresses+0x114/0x17d [rpcrdma] [<00000000dfa6ed00>] xprt_setup_rdma_bc+0xc0/0x10c [rpcrdma] [<0000000073051a83>] xprt_create_transport+0x3f/0x1a0 [sunrpc] [<0000000053531a8e>] rpc_create+0x118/0x1cd [sunrpc] [<000000003a51b5f8>] setup_callback_client+0x1a5/0x27d [nfsd] [<000000001bd410af>] nfsd4_process_cb_update.isra.7+0x16c/0x1ac [nfsd] [<000000007f4bbd56>] nfsd4_run_cb_work+0x4c/0xbd [nfsd] [<0000000055c5586b>] process_one_work+0x1b2/0x2fe [<00000000b1e3e8ef>] worker_thread+0x1a6/0x25a [<000000005205fb78>] kthread+0xf6/0xfb [<000000006d2dc057>] ret_from_fork+0x3a/0x50 Introduce a call to xprt_rdma_free_addresses() similar to the way that the TCP backchannel releases a transport's peer address strings. Fixes: 5d252f90a800 ("svcrdma: Add class for RDMA backwards direction transport") Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16svcrdma: Fix double sync of transport header bufferChuck Lever1-1/+0
Performance optimization: Avoid syncing the transport buffer twice when Reply buffer pull-up is necessary. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16svcrdma: Refactor chunk list encodersChuck Lever1-6/+9
Same idea as the receive-side changes I did a while back: use xdr_stream helpers rather than open-coding the XDR chunk list encoders. This builds the Reply transport header from beginning to end without backtracking. As additional clean-ups, fill in documenting comments for the XDR encoders and sprinkle some trace points in the new encoding functions. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16svcrdma: Update synopsis of svc_rdma_map_reply_msg()Chuck Lever1-1/+1
Preparing for subsequent patches, no behavior change expected. Pass the RPC Call's svc_rdma_recv_ctxt deeper into the sendto() path. This enables passing more information about Requester- provided Write and Reply chunks into those lower-level functions. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2019-11-22SUNRPC: Fix backchannel latency metricsChuck Lever1-0/+1
I noticed that for callback requests, the reported backlog latency is always zero, and the rtt value is crazy big. The problem was that rqst->rq_xtime is never set for backchannel requests. Fixes: 78215759e20d ("SUNRPC: Make RTT measurement more ... ") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-07-06SUNRPC: Remove the bh-safe lock requirement on xprt->transport_lockTrond Myklebust1-2/+2
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-04-25SUNRPC: Refactor xprt_request_wait_receive()Trond Myklebust1-1/+1
Convert the transport callback to actually put the request to sleep instead of just setting a timeout. This is in preparation for rpc_sleep_on_timeout(). Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-02-13SUNRPC: Remove rpc_xprt::tsh_sizeChuck Lever1-1/+0
tsh_size was added to accommodate transports that send a pre-amble before each RPC message. However, this assumes the pre-amble is fixed in size, which isn't true for some transports. That makes tsh_size not very generic. Also I'd like to make the estimation of RPC send and receive buffer sizes more precise. tsh_size doesn't currently appear to be accounted for at all by call_allocate. Therefore let's just remove the tsh_size concept, and make the only transports that have a non-zero tsh_size employ a direct approach. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2019-01-02xprtrdma: Don't wake pending tasks until disconnect is doneChuck Lever1-3/+5
Transport disconnect processing does a "wake pending tasks" at various points. Suppose an RPC Reply is being processed. The RPC task that Reply goes with is waiting on the pending queue. If a disconnect wake-up happens before reply processing is done, that reply, even if it is good, is thrown away, and the RPC has to be sent again. This window apparently does not exist for socket transports because there is a lock held while a reply is being received which prevents the wake-up call until after reply processing is done. To resolve this, all RPC replies being processed on an RPC-over-RDMA transport have to complete before pending tasks are awoken due to a transport disconnect. Callers that already hold the transport write lock may invoke ->ops->close directly. Others use a generic helper that schedules a close when the write lock can be taken safely. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-10-30Merge tag 'nfsd-4.20' of git://linux-nfs.org/~bfields/linuxLinus Torvalds1-19/+4
Pull nfsd updates from Bruce Fields: "Olga added support for the NFSv4.2 asynchronous copy protocol. We already supported COPY, by copying a limited amount of data and then returning a short result, letting the client resend. The asynchronous protocol should offer better performance at the expense of some complexity. The other highlight is Trond's work to convert the duplicate reply cache to a red-black tree, and to move it and some other server caches to RCU. (Previously these have meant taking global spinlocks on every RPC) Otherwise, some RDMA work and miscellaneous bugfixes" * tag 'nfsd-4.20' of git://linux-nfs.org/~bfields/linux: (30 commits) lockd: fix access beyond unterminated strings in prints nfsd: Fix an Oops in free_session() nfsd: correctly decrement odstate refcount in error path svcrdma: Increase the default connection credit limit svcrdma: Remove try_module_get from backchannel svcrdma: Remove ->release_rqst call in bc reply handler svcrdma: Reduce max_send_sges nfsd: fix fall-through annotations knfsd: Improve lookup performance in the duplicate reply cache using an rbtree knfsd: Further simplify the cache lookup knfsd: Simplify NFS duplicate replay cache knfsd: Remove dead code from nfsd_cache_lookup SUNRPC: Simplify TCP receive code SUNRPC: Replace the cache_detail->hash_lock with a regular spinlock SUNRPC: Remove non-RCU protected lookup NFS: Fix up a typo in nfs_dns_ent_put NFS: Lockless DNS lookups knfsd: Lockless lookup of NFSv4 identities. SUNRPC: Lockless server RPCSEC_GSS context lookup knfsd: Allow lockless lookups of the exports ...
2018-10-29svcrdma: Remove try_module_get from backchannelChuck Lever1-14/+0
Since commit ffe1f0df5862 ("rpcrdma: Merge svcrdma and xprtrdma modules into one"), the forward and backchannel components are part of the same kernel module. A separate try_module_get() call in the backchannel code is no longer necessary. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-10-29svcrdma: Remove ->release_rqst call in bc reply handlerChuck Lever1-5/+4
Similar to a change made in the client's forward channel reply handler: The xprt_release_rqst_cong() call is not necessary. Also, release xprt->recv_lock when taking xprt->transport_lock to avoid disabling and enabling BH's while holding another spin lock. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-10-19Merge tag 'nfs-rdma-for-4.20-1' of ↵Trond Myklebust1-0/+1
git://git.linux-nfs.org/projects/anna/linux-nfs NFS RDMA client updates for Linux 4.20 Stable bugfixes: - Reset credit grant properly after a disconnect Other bugfixes and cleanups: - xprt_release_rqst_cong is called outside of transport_lock - Create more MRs at a time and toss out old ones during recovery - Various improvements to the RDMA connection and disconnection code: - Improve naming of trace events, functions, and variables - Add documenting comments - Fix metrics and stats reporting - Fix a tracepoint sparse warning Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-10-02xprtrdma: Reset credit grant properly after a disconnectChuck Lever1-0/+1
On a fresh connection, an RPC/RDMA client is supposed to send only one RPC Call until it gets a credit grant in the first RPC Reply from the server [RFC 8166, Section 3.3.3]. There is a bug in the Linux client's credit accounting mechanism introduced by commit e7ce710a8802 ("xprtrdma: Avoid deadlock when credit window is reset"). On connect, it simply dumps all pending RPC Calls onto the new connection. Servers have been tolerant of this bad behavior. Currently no server implementation ever changes its credit grant over reconnects, and servers always repost enough Receives before connections are fully established. To correct this issue, ensure that the client resets both the credit grant _and_ the congestion window when handling a reconnect. Fixes: e7ce710a8802 ("xprtrdma: Avoid deadlock when credit ... ") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Cc: stable@kernel.org Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-09-30SUNRPC: Cleanup: remove the unused 'task' argument from the request_send()Trond Myklebust1-1/+1
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30SUNRPC: Clean up transport write space handlingTrond Myklebust1-6/+1
Treat socket write space handling in the same way we now treat transport congestion: by denying the XPRT_LOCK until the transport signals that it has free buffer space. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30SUNRPC: Treat the task and request as separate in the xprt_ops->send_request()Trond Myklebust1-2/+1
When we shift to using the transmit queue, then the task that holds the write lock will not necessarily be the same as the one being transmitted. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-09-30SUNRPC: Rename xprt->recv_lock to xprt->queue_lockTrond Myklebust1-2/+2
We will use the same lock to protect both the transmit and receive queues. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-06-12Merge tag 'nfs-for-4.18-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds1-0/+1
Pull NFS client updates from Trond Myklebust: "Highlights include: Stable fixes: - Fix a 1-byte stack overflow in nfs_idmap_read_and_verify_message - Fix a hang due to incorrect error returns in rpcrdma_convert_iovs() - Revert an incorrect change to the NFSv4.1 callback channel - Fix a bug in the NFSv4.1 sequence error handling Features and optimisations: - Support for piggybacking a LAYOUTGET operation to the OPEN compound - RDMA performance enhancements to deal with transport congestion - Add proper SPDX tags for NetApp-contributed RDMA source - Do not request delegated file attributes (size+change) from the server - Optimise away a GETATTR in the lookup revalidate code when doing NFSv4 OPEN - Optimise away unnecessary lookups for rename targets - Misc performance improvements when freeing NFSv4 delegations Bugfixes and cleanups: - Try to fail quickly if proto=rdma - Clean up RDMA receive trace points - Fix sillyrename to return the delegation when appropriate - Misc attribute revalidation fixes - Immediately clear the pNFS layout on a file when the server returns ESTALE - Return NFS4ERR_DELAY when delegation/layout recalls fail due to igrab() - Fix the client behaviour on NFS4ERR_SEQ_FALSE_RETRY" * tag 'nfs-for-4.18-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (80 commits) skip LAYOUTRETURN if layout is invalid NFSv4.1: Fix the client behaviour on NFS4ERR_SEQ_FALSE_RETRY NFSv4: Fix a typo in nfs41_sequence_process NFSv4: Revert commit 5f83d86cf531d ("NFSv4.x: Fix wraparound issues..") NFSv4: Return NFS4ERR_DELAY when a layout recall fails due to igrab() NFSv4: Return NFS4ERR_DELAY when a delegation recall fails due to igrab() NFSv4.0: Remove transport protocol name from non-UCS client ID NFSv4.0: Remove cl_ipaddr from non-UCS client ID NFSv4: Fix a compiler warning when CONFIG_NFS_V4_1 is undefined NFS: Filter cache invalidation when holding a delegation NFS: Ignore NFS_INO_REVAL_FORCED in nfs_check_inode_attributes() NFS: Improve caching while holding a delegation NFS: Fix attribute revalidation NFS: fix up nfs_setattr_update_inode NFSv4: Ensure the inode is clean when we set a delegation NFSv4: Ignore NFS_INO_REVAL_FORCED in nfs4_proc_access NFSv4: Don't ask for delegated attributes when adding a hard link NFSv4: Don't ask for delegated attributes when revalidating the inode NFS: Pass the inode down to the getattr() callback NFSv4: Don't request size+change attribute if they are delegated to us ...
2018-05-11svcrdma: Persistently allocate and DMA-map Send buffersChuck Lever1-34/+17
While sending each RPC Reply, svc_rdma_sendto allocates and DMA- maps a separate buffer where the RPC/RDMA transport header is constructed. The buffer is unmapped and released in the Send completion handler. This is significant per-RPC overhead, especially for small RPCs. Instead, allocate and DMA-map a buffer, and cache it in each svc_rdma_send_ctxt. This buffer and its mapping can be re-used for each RPC, saving the cost of memory allocation and DMA mapping. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-05-11svcrdma: Remove post_send_wrChuck Lever1-1/+2
Clean up: Now that the send_wr is part of the svc_rdma_send_ctxt, svc_rdma_post_send_wr is nearly empty. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-05-11svcrdma: Introduce svc_rdma_send_ctxtChuck Lever1-5/+8
svc_rdma_op_ctxt's are pre-allocated and maintained on a per-xprt free list. This eliminates the overhead of calling kmalloc / kfree, both of which grab a globally shared lock that disables interrupts. Introduce a replacement to svc_rdma_op_ctxt's that is built especially for the svcrdma Send path. Subsequent patches will take advantage of this new structure by allocating real resources which are then cached in these objects. The allocations are freed when the transport is torn down. I've renamed the structure so that static type checking can be used to ensure that uses of op_ctxt and send_ctxt are not confused. As an additional clean up, structure fields are renamed to conform with kernel coding conventions. Additional clean ups: - Handle svc_rdma_send_ctxt_get allocation failure at each call site, rather than pre-allocating and hoping we guessed correctly - All send_ctxt_put call-sites request page freeing, so remove the @free_pages argument - All send_ctxt_put call-sites unmap SGEs, so fold that into svc_rdma_send_ctxt_put Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-05-11svcrdma: Clean up Send SGE accountingChuck Lever1-1/+1
Clean up: Since there's already a svc_rdma_op_ctxt being passed around with the running count of mapped SGEs, drop unneeded parameters to svc_rdma_post_send_wr(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-05-11svcrdma: Trace key RDMA API eventsChuck Lever1-0/+3
This includes: * Posting on the Send and Receive queues * Send, Receive, Read, and Write completion * Connect upcalls * QP errors Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-05-07SUNRPC: Add a ->free_slot transport calloutChuck Lever1-0/+1
Refactor: xprtrdma needs to have better control over when RPCs are awoken from the backlog queue, so replace xprt_free_slot with a transport op callout. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-01-18svcrdma: Post Receives in the Receive completion handlerChuck Lever1-5/+0
This change improves Receive efficiency by posting Receives only on the same CPU that handles Receive completion. Improved latency and throughput has been noted with this change. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-11-18Merge tag 'nfsd-4.15' of git://linux-nfs.org/~bfields/linuxLinus Torvalds1-1/+5
Pull nfsd updates from Bruce Fields: "Lots of good bugfixes, including: - fix a number of races in the NFSv4+ state code - fix some shutdown crashes in multiple-network-namespace cases - relax our 4.1 session limits; if you've an artificially low limit to the number of 4.1 clients that can mount simultaneously, try upgrading" * tag 'nfsd-4.15' of git://linux-nfs.org/~bfields/linux: (22 commits) SUNRPC: Improve ordering of transport processing nfsd: deal with revoked delegations appropriately svcrdma: Enqueue after setting XPT_CLOSE in completion handlers nfsd: use nfs->ns.inum as net ID rpc: remove some BUG()s svcrdma: Preserve CB send buffer across retransmits nfds: avoid gettimeofday for nfssvc_boot time fs, nfsd: convert nfs4_file.fi_ref from atomic_t to refcount_t fs, nfsd: convert nfs4_cntl_odstate.co_odcount from atomic_t to refcount_t fs, nfsd: convert nfs4_stid.sc_count from atomic_t to refcount_t lockd: double unregister of inetaddr notifiers nfsd4: catch some false session retries nfsd4: fix cached replies to solo SEQUENCE compounds sunrcp: make function _svc_create_xprt static SUNRPC: Fix tracepoint storage issues with svc_recv and svc_rqst_status nfsd: use ARRAY_SIZE nfsd: give out fewer session slots as limit approaches nfsd: increase DRC cache limit nfsd: remove unnecessary nofilehandle checks nfs_common: convert int to bool ...
2017-11-08svcrdma: Preserve CB send buffer across retransmitsChuck Lever1-1/+5
During each NFSv4 callback Call, an RDMA Send completion frees the page that contains the RPC Call message. If the upper layer determines that a retransmit is necessary, this is too soon. One possible symptom: after a GARBAGE_ARGS response an NFSv4.1 callback request, the following BUG fires on the NFS server: kernel: BUG: Bad page state in process kworker/0:2H pfn:7d3ce2 kernel: page:ffffea001f4f3880 count:-2 mapcount:0 mapping: (null) index:0x0 kernel: flags: 0x2fffff80000000() kernel: raw: 002fffff80000000 0000000000000000 0000000000000000 fffffffeffffffff kernel: raw: dead000000000100 dead000000000200 0000000000000000 0000000000000000 kernel: page dumped because: nonzero _refcount kernel: Modules linked in: cts rpcsec_gss_krb5 ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue rpcrdm a ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass crct10dif_pc lmul crc32_pclmul ghash_clmulni_intel pcbc iTCO_wdt iTCO_vendor_support aesni_intel crypto_simd glue_helper cryptd pcspkr lpc_ich i2c_i801 mei_me mf d_core mei raid0 sg wmi ioatdma ipmi_si ipmi_devintf ipmi_msghandler shpchp acpi_power_meter acpi_pad nfsd nfs_acl lockd auth_rpcgss grace sunrpc ip_tables xfs libcrc32c mlx4_en mlx4_ib mlx5_ib ib_core sd_mod sr_mod cdrom ast drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm ahci crc32c_intel libahci drm mlx5_core igb libata mlx4_core dca i2c_algo_bit i2c_core nvme kernel: ptp nvme_core pps_core dm_mirror dm_region_hash dm_log dm_mod dax kernel: CPU: 0 PID: 11495 Comm: kworker/0:2H Not tainted 4.14.0-rc3-00001-g577ce48 #811 kernel: Hardware name: Supermicro Super Server/X10SRL-F, BIOS 1.0c 09/09/2015 kernel: Workqueue: ib-comp-wq ib_cq_poll_work [ib_core] kernel: Call Trace: kernel: dump_stack+0x62/0x80 kernel: bad_page+0xfe/0x11a kernel: free_pages_check_bad+0x76/0x78 kernel: free_pcppages_bulk+0x364/0x441 kernel: ? ttwu_do_activate.isra.61+0x71/0x78 kernel: free_hot_cold_page+0x1c5/0x202 kernel: __put_page+0x2c/0x36 kernel: svc_rdma_put_context+0xd9/0xe4 [rpcrdma] kernel: svc_rdma_wc_send+0x50/0x98 [rpcrdma] This issue exists all the way back to v4.5, but refactoring and code re-organization prevents this simple patch from applying to kernels older than v4.12. The fix is the same, however, if someone needs to backport it. Reported-by: Ben Coddington <bcodding@redhat.com> BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=314 Fixes: 5d252f90a800 ('svcrdma: Add class for RDMA backwards ... ') Cc: stable@vger.kernel.org # v4.12 Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+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>
2017-09-05Merge tag 'nfs-rdma-for-4.14-1' of ↵Trond Myklebust1-1/+1
git://git.linux-nfs.org/projects/anna/linux-nfs into linux-next NFS-over-RDMA client updates for Linux 4.14 Bugfixes and cleanups: - Constify rpc_xprt_ops - Harden RPC call encoding and decoding - Clean up rpc call decoding to use xdr_streams - Remove unused variables from various structures - Refactor code to remove imul instructions - Rearrange rx_stats structure for better cacheline sharing
2017-08-18SUNRPC: Add a separate spinlock to protect the RPC request receive listTrond Myklebust1-2/+5
This further reduces contention with the transport_lock, and allows us to convert to using a non-bh-safe spinlock, since the list is now never accessed from a bh context. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-01sunrpc: Const-ify all instances of struct rpc_xprt_opsChuck Lever1-1/+1
After transport instance creation, these function pointers never change. Mark them as constant to prevent their use as an attack vector for code injections. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-04-26svcrdma: Clean up RPC-over-RDMA backchannel reply processingChuck Lever1-4/+14
Replace C structure-based XDR decoding with pointer arithmetic. Pointer arithmetic is considered more portable. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-04-26svcrdma: Use rdma_rw API in RPC reply pathChuck Lever1-3/+3
The current svcrdma sendto code path posts one RDMA Write WR at a time. Each of these Writes typically carries a small number of pages (for instance, up to 30 pages for mlx4 devices). That means a 1MB NFS READ reply requires 9 ib_post_send() calls for the Write WRs, and one for the Send WR carrying the actual RPC Reply message. Instead, use the new rdma_rw API. The details of Write WR chain construction and memory registration are taken care of in the RDMA core. svcrdma can focus on the details of the RPC-over-RDMA protocol. This gives three main benefits: 1. All Write WRs for one RDMA segment are posted in a single chain. As few as one ib_post_send() for each Write chunk. 2. The Write path can now use FRWR to register the Write buffers. If the device's maximum page list depth is large, this means a single Write WR is needed for each RPC's Write chunk data. 3. The new code introduces support for RPCs that carry both a Write list and a Reply chunk. This combination can be used for an NFSv4 READ where the data payload is large, and thus is removed from the Payload Stream, but the Payload Stream is still larger than the inline threshold. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-04-26svcrdma: Add svc_rdma_map_reply_hdr()Chuck Lever1-25/+11
Introduce a helper to DMA-map a reply's transport header before sending it. This will in part replace the map vector cache. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-04-26svcrdma: Move send_wr to svc_rdma_op_ctxtChuck Lever1-10/+1
Clean up: Move the ib_send_wr off the stack, and move common code to post a Send Work Request into a helper. This is a refactoring change only. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-03-01Merge tag 'nfsd-4.11' of git://linux-nfs.org/~bfields/linuxLinus Torvalds1-8/+9
Pull nfsd updates from Bruce Fields: "The nfsd update this round is mainly a lot of miscellaneous cleanups and bugfixes. A couple changes could theoretically break working setups on upgrade. I don't expect complaints in practice, but they seem worth calling out just in case: - NFS security labels are now off by default; a new security_label export flag reenables it per export. But, having them on by default is a disaster, as it generally only makes sense if all your clients and servers have similar enough selinux policies. Thanks to Jason Tibbitts for pointing this out. - NFSv4/UDP support is off. It was never really supported, and the spec explicitly forbids it. We only ever left it on out of laziness; thanks to Jeff Layton for finally fixing that" * tag 'nfsd-4.11' of git://linux-nfs.org/~bfields/linux: (34 commits) nfsd: Fix display of the version string nfsd: fix configuration of supported minor versions sunrpc: don't register UDP port with rpcbind when version needs congestion control nfs/nfsd/sunrpc: enforce transport requirements for NFSv4 sunrpc: flag transports as having congestion control sunrpc: turn bitfield flags in svc_version into bools nfsd: remove superfluous KERN_INFO nfsd: special case truncates some more nfsd: minor nfsd_setattr cleanup NFSD: Reserve adequate space for LOCKT operation NFSD: Get response size before operation for all RPCs nfsd/callback: Drop a useless data copy when comparing sessionid nfsd/callback: skip the callback tag nfsd/callback: Cleanup callback cred on shutdown nfsd/idmap: return nfserr_inval for 0-length names SUNRPC/Cache: Always treat the invalid cache as unexpired SUNRPC: Drop all entries from cache_detail when cache_purge() svcrdma: Poll CQs in "workqueue" mode svcrdma: Combine list fields in struct svc_rdma_op_ctxt svcrdma: Remove unused sc_dto_q field ...
2017-02-10net: sunrpc: fix build errors when linux/phy*.h is removed from net/dsa.hRussell King1-0/+1
Removing linux/phy.h from net/dsa.h reveals a build error in the sunrpc code: net/sunrpc/xprtrdma/svc_rdma_backchannel.c: In function 'xprt_rdma_bc_put': net/sunrpc/xprtrdma/svc_rdma_backchannel.c:277:2: error: implicit declaration of function 'module_put' [-Werror=implicit-function-declaration] net/sunrpc/xprtrdma/svc_rdma_backchannel.c: In function 'xprt_setup_rdma_bc': net/sunrpc/xprtrdma/svc_rdma_backchannel.c:348:7: error: implicit declaration of function 'try_module_get' [-Werror=implicit-function-declaration] Fix this by adding linux/module.h to svc_rdma_backchannel.c Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-08svcrdma: Clean up backchannel send header encodingChuck Lever1-8/+9
Replace C structure-based XDR decoding with pointer arithmetic. Pointer arithmetic is considered more portable. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-12-01svcrdma: Remove unused variables in xprt_rdma_bc_allocate()Chuck Lever1-4/+0
Clean up. /linux-2.6/net/sunrpc/xprtrdma/svc_rdma_backchannel.c: In function ‘xprt_rdma_bc_allocate’: linux-2.6/net/sunrpc/xprtrdma/svc_rdma_backchannel.c:169:23: warning: variable ‘rdma’ set but not used [-Wunused-but-set-variable] struct svcxprt_rdma *rdma; ^ Fixes: 5d252f90a800 ("svcrdma: Add class for RDMA backwards ...") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>