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2017-11-17NFS: Fix typo in nomigration mount optionJoshua Watt
The option was incorrectly masking off all other options. Signed-off-by: Joshua Watt <JPEWhacker@gmail.com> Cc: stable@vger.kernel.org #3.7 Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17nfs: Fix ugly referral attributesChuck Lever
Before traversing a referral and performing a mount, the mounted-on directory looks strange: dr-xr-xr-x. 2 4294967294 4294967294 0 Dec 31 1969 dir.0 nfs4_get_referral is wiping out any cached attributes with what was returned via GETATTR(fs_locations), but the bit mask for that operation does not request any file attributes. Retrieve owner and timestamp information so that the memcpy in nfs4_get_referral fills in more attributes. Changes since v1: - Don't request attributes that the client unconditionally replaces - Request only MOUNTED_ON_FILEID or FILEID attribute, not both - encode_fs_locations() doesn't use the third bitmask word Fixes: 6b97fd3da1ea ("NFSv4: Follow a referral") Suggested-by: Pradeep Thomas <pradeepthomas@gmail.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFS: super: mark expected switch fall-throughsGustavo A. R. Silva
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Addresses-Coverity-ID: 703509 Addresses-Coverity-ID: 703510 Addresses-Coverity-ID: 703511 Addresses-Coverity-ID: 703512 Addresses-Coverity-ID: 703513 Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17sunrpc: remove net pointer from messagesVasily Averin
Publishing of net pointer is not safe, use net->ns.inum as net ID [ 171.391947] RPC: created new rpcb local clients (rpcb_local_clnt: ..., rpcb_local_clnt4: ...) for net f00001e7 [ 171.767188] NFSD: starting 90-second grace period (net f00001e7) Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17nfs: remove net pointer from messagesVasily Averin
Publishing of net pointer is not safe, use net->ns.inum instead Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17sunrpc: exit_net cleanup check addedVasily Averin
Be sure that all_clients list initialized in net_init hook was return to initial state. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17nfs client: exit_net cleanup check addedVasily Averin
Be sure that nfs_client_list and nfs_volume_list lists initialized in net_init hook were return to initial state in net_exit hook. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17nfs/write: Use common error handling code in nfs_lock_and_join_requests()Markus Elfring
Add a jump target so that a bit of exception handling can be better reused at the end of this function. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFSv4: Replace closed stateids with the "invalid special stateid"Trond Myklebust
When decoding a CLOSE, replace the stateid returned by the server with the "invalid special stateid" described in RFC5661, Section 8.2.3. In nfs_set_open_stateid_locked, ignore stateids from closed state. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFSv4: nfs_set_open_stateid must not trigger state recovery for closed stateTrond Myklebust
In nfs_set_open_stateid_locked, we must ignore stateids from closed state. Reported-by: Andrew W Elble <aweits@rit.edu> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFSv4: Check the open stateid when searching for expired stateTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFSv4: Clean up nfs4_delegreturn_doneTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFSv4: cleanup nfs4_close_doneTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFSv4: Retry NFS4ERR_OLD_STATEID errors in layoutreturnTrond Myklebust
If our layoutreturn returns an NFS4ERR_OLD_STATEID, then try to update the stateid and retry. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17pNFS: Retry NFS4ERR_OLD_STATEID errors in layoutreturn-on-closeTrond Myklebust
If our layoutreturn on close operation returns an NFS4ERR_OLD_STATEID, then try to update the stateid and retry. We know that there should be no further LAYOUTGET requests being launched. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFSv4: Don't try to CLOSE if the stateid 'other' field has changedTrond Myklebust
If the stateid is no longer recognised on the server, either due to a restart, or due to a competing CLOSE call, then we do not have to retry. Any open contexts that triggered a reopen of the file, will also act as triggers for any CLOSE for the updated stateids. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFSv4: Retry CLOSE and DELEGRETURN on NFS4ERR_OLD_STATEID.Trond Myklebust
If we're racing with an OPEN, then retry the operation instead of declaring it a success. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> [Andrew W Elble: Fix a typo in nfs4_refresh_open_stateid] Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFS: Fix a typo in nfs_rename()Trond Myklebust
On successful rename, the "old_dentry" is retained and is attached to the "new_dir", so we need to call nfs_set_verifier() accordingly. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFSv4: Fix open create exclusive when the server rebootsTrond Myklebust
If the server that does not implement NFSv4.1 persistent session semantics reboots while we are performing an exclusive create, then the return value of NFS4ERR_DELAY when we replay the open during the grace period causes us to lose the verifier. When the grace period expires, and we present a new verifier, the server will then correctly reply NFS4ERR_EXIST. This commit ensures that we always present the same verifier when replaying the OPEN. Reported-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFSv4: Add a tracepoint to document open stateid updatesTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFSv4: Fix OPEN / CLOSE raceTrond Myklebust
Ben Coddington has noted the following race between OPEN and CLOSE on a single client. Process 1 Process 2 Server ========= ========= ====== 1) OPEN file 2) OPEN file 3) Process OPEN (1) seqid=1 4) Process OPEN (2) seqid=2 5) Reply OPEN (2) 6) Receive reply (2) 7) new stateid, seqid=2 8) CLOSE file, using stateid w/ seqid=2 9) Reply OPEN (1) 10( Process CLOSE (8) 11) Reply CLOSE (8) 12) Forget stateid file closed 13) Receive reply (7) 14) Forget stateid file closed. 15) Receive reply (1). 16) New stateid seqid=1 is really the same stateid that was closed. IOW: the reply to the first OPEN is delayed. Since "Process 2" does not wait before closing the file, and it does not cache the closed stateid, then when the delayed reply is finally received, it is treated as setting up a new stateid by the client. The fix is to ensure that the client processes the OPEN and CLOSE calls in the same order in which the server processed them. This commit ensures that we examine the seqid of the stateid returned by OPEN. If it is a new stateid, we assume the seqid must be equal to the value 1, and that each state transition increments the seqid value by 1 (See RFC7530, Section 9.1.4.2, and RFC5661, Section 8.2.2). If the tracker sees that an OPEN returns with a seqid that is greater than the cached seqid + 1, then it bumps a flag to ensure that the caller waits for the RPCs carrying the missing seqids to complete. Note that there can still be pathologies where the server crashes before it can even send us the missing seqids. Since the OPEN call is still holding a slot when it waits here, that could cause the recovery to stall forever. To avoid that, we time out after a 5 second wait. Reported-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17sunrpc: Add rpc_request static trace pointChuck Lever
Display information about the RPC procedure being requested in the trace log. This sometimes critical information cannot always be derived from other RPC trace entries. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17sunrpc: Fix rpc_task_begin trace pointChuck Lever
The rpc_task_begin trace point always display a task ID of zero. Move the trace point call site so that it picks up the new task ID. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17SUNRPC: Fix parsing failure in trace points with XIDsChuck Lever
mount.nf-11159 8.... 905.248380: xprt_transmit: [FAILED TO PARSE] xid=351291440 status=0 addr=192.168.2.5 port=20049 mount.nf-11159 8.... 905.248381: rpc_task_sleep: task:6210@1 flags=0e80 state=0005 status=0 timeout=60000 queue=xprt_pending kworker/-1591 1.... 905.248419: xprt_lookup_rqst: [FAILED TO PARSE] xid=351291440 status=0 addr=192.168.2.5 port=20049 kworker/-1591 1.... 905.248423: xprt_complete_rqst: [FAILED TO PARSE] xid=351291440 status=24 addr=192.168.2.5 port=20049 Byte swapping is not available during trace-cmd report. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17net: sunrpc: mark expected switch fall-throughsGustavo A. R. Silva
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFS: Fix bool initialization/comparisonThomas Meyer
Bool initializations should use true and false. Bool tests don't need comparisons. Signed-off-by: Thomas Meyer <thomas@m3y3r.de> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFS: Avoid RCU usage in tracepointsAnna Schumaker
There isn't an obvious way to acquire and release the RCU lock during a tracepoint, so we can't use the rpc_peeraddr2str() function here. Instead, rely on the client's cl_hostname, which should have similar enough information without needing an rcu_dereference(). Reported-by: Dave Jones <davej@codemonkey.org.uk> Cc: stable@vger.kernel.org # v3.12 Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17xprtrdma: Update copyright noticesChuck Lever
Credit work contributed by Oracle engineers since 2014. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17xprtrdma: Remove include for linux/prefetch.hChuck Lever
Clean up. This include should have been removed by commit 23826c7aeac7 ("xprtrdma: Serialize credit accounting again"). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Devesh Sharma <devesh.sharma@broadcom.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17rpcrdma: Remove C structure definitions of XDR data itemsChuck Lever
Clean up: C-structure style XDR encoding and decoding logic has been replaced over the past several merge windows on both the client and server. These data structures are no longer used. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Devesh Sharma <devesh.sharma@broadcom.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17xprtrdma: Put Send CQ in IB_POLL_WORKQUEUE modeChuck Lever
Lift the Send and LocalInv completion handlers out of soft IRQ mode to make room for other work. Also, move the Send CQ to a different CPU than the CPU where the Receive CQ is running, for improved scalability. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Devesh Sharma <devesh.sharma@broadcom.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17fs, nfs: convert nfs_client.cl_count from atomic_t to refcount_tElena Reshetova
atomic_t variables are currently used to implement reference counters with the following properties: - counter is initialized to 1 using atomic_set() - a resource is freed upon counter reaching zero - once counter reaches zero, its further increments aren't allowed - counter schema uses basic atomic operations (set, inc, inc_not_zero, dec_and_test, etc.) Such atomic variables should be converted to a newly provided refcount_t type and API that prevents accidental counter overflows and underflows. This is important since overflows and underflows can lead to use-after-free situation and be exploitable. The variable nfs_client.cl_count is used as pure reference counter. Convert it to refcount_t and fix up the operations. Suggested-by: Kees Cook <keescook@chromium.org> Reviewed-by: David Windsor <dwindsor@gmail.com> Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17fs, nfs: convert nfs_lock_context.count from atomic_t to refcount_tElena Reshetova
atomic_t variables are currently used to implement reference counters with the following properties: - counter is initialized to 1 using atomic_set() - a resource is freed upon counter reaching zero - once counter reaches zero, its further increments aren't allowed - counter schema uses basic atomic operations (set, inc, inc_not_zero, dec_and_test, etc.) Such atomic variables should be converted to a newly provided refcount_t type and API that prevents accidental counter overflows and underflows. This is important since overflows and underflows can lead to use-after-free situation and be exploitable. The variable nfs_lock_context.count is used as pure reference counter. Convert it to refcount_t and fix up the operations. Suggested-by: Kees Cook <keescook@chromium.org> Reviewed-by: David Windsor <dwindsor@gmail.com> Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17fs, nfs: convert nfs4_lock_state.ls_count from atomic_t to refcount_tElena Reshetova
atomic_t variables are currently used to implement reference counters with the following properties: - counter is initialized to 1 using atomic_set() - a resource is freed upon counter reaching zero - once counter reaches zero, its further increments aren't allowed - counter schema uses basic atomic operations (set, inc, inc_not_zero, dec_and_test, etc.) Such atomic variables should be converted to a newly provided refcount_t type and API that prevents accidental counter overflows and underflows. This is important since overflows and underflows can lead to use-after-free situation and be exploitable. The variable nfs4_lock_state.ls_count is used as pure reference counter. Convert it to refcount_t and fix up the operations. Suggested-by: Kees Cook <keescook@chromium.org> Reviewed-by: David Windsor <dwindsor@gmail.com> Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17fs, nfs: convert nfs_cache_defer_req.count from atomic_t to refcount_tElena Reshetova
atomic_t variables are currently used to implement reference counters with the following properties: - counter is initialized to 1 using atomic_set() - a resource is freed upon counter reaching zero - once counter reaches zero, its further increments aren't allowed - counter schema uses basic atomic operations (set, inc, inc_not_zero, dec_and_test, etc.) Such atomic variables should be converted to a newly provided refcount_t type and API that prevents accidental counter overflows and underflows. This is important since overflows and underflows can lead to use-after-free situation and be exploitable. The variable nfs_cache_defer_req.count is used as pure reference counter. Convert it to refcount_t and fix up the operations. Suggested-by: Kees Cook <keescook@chromium.org> Reviewed-by: David Windsor <dwindsor@gmail.com> Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17fs, nfs: convert nfs4_ff_layout_mirror.ref from atomic_t to refcount_tElena Reshetova
atomic_t variables are currently used to implement reference counters with the following properties: - counter is initialized to 1 using atomic_set() - a resource is freed upon counter reaching zero - once counter reaches zero, its further increments aren't allowed - counter schema uses basic atomic operations (set, inc, inc_not_zero, dec_and_test, etc.) Such atomic variables should be converted to a newly provided refcount_t type and API that prevents accidental counter overflows and underflows. This is important since overflows and underflows can lead to use-after-free situation and be exploitable. The variable nfs4_ff_layout_mirror.ref is used as pure reference counter. Convert it to refcount_t and fix up the operations. Suggested-by: Kees Cook <keescook@chromium.org> Reviewed-by: David Windsor <dwindsor@gmail.com> Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17fs, nfs: convert pnfs_layout_hdr.plh_refcount from atomic_t to refcount_tElena Reshetova
atomic_t variables are currently used to implement reference counters with the following properties: - counter is initialized to 1 using atomic_set() - a resource is freed upon counter reaching zero - once counter reaches zero, its further increments aren't allowed - counter schema uses basic atomic operations (set, inc, inc_not_zero, dec_and_test, etc.) Such atomic variables should be converted to a newly provided refcount_t type and API that prevents accidental counter overflows and underflows. This is important since overflows and underflows can lead to use-after-free situation and be exploitable. The variable pnfs_layout_hdr.plh_refcount is used as pure reference counter. Convert it to refcount_t and fix up the operations. Suggested-by: Kees Cook <keescook@chromium.org> Reviewed-by: David Windsor <dwindsor@gmail.com> Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17fs, nfs: convert pnfs_layout_segment.pls_refcount from atomic_t to refcount_tElena Reshetova
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17fs, nfs: convert nfs4_pnfs_ds.ds_count from atomic_t to refcount_tElena Reshetova
atomic_t variables are currently used to implement reference counters with the following properties: - counter is initialized to 1 using atomic_set() - a resource is freed upon counter reaching zero - once counter reaches zero, its further increments aren't allowed - counter schema uses basic atomic operations (set, inc, inc_not_zero, dec_and_test, etc.) Such atomic variables should be converted to a newly provided refcount_t type and API that prevents accidental counter overflows and underflows. This is important since overflows and underflows can lead to use-after-free situation and be exploitable. The variable nfs4_pnfs_ds.ds_count is used as pure reference counter. Convert it to refcount_t and fix up the operations. Suggested-by: Kees Cook <keescook@chromium.org> Reviewed-by: David Windsor <dwindsor@gmail.com> Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17NFSv4.1: Fix up replays of interrupted requestsTrond Myklebust
If the previous request on a slot was interrupted before it was processed by the server, then our slot sequence number may be out of whack, and so we try the next operation using the old sequence number. The problem with this, is that not all servers check to see that the client is replaying the same operations as previously when they decide to go to the replay cache, and so instead of the expected error of NFS4ERR_SEQ_FALSE_RETRY, we get a replay of the old reply, which could (if the operations match up) be mistaken by the client for a new reply. To fix this, we attempt to send a COMPOUND containing only the SEQUENCE op in order to resync our slot sequence number. Cc: Olga Kornievskaia <olga.kornievskaia@gmail.com> [olga.kornievskaia@gmail.com: fix an Oops] Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17xprtrdma: Remove atomic send completion countingChuck Lever
The sendctx circular queue now guarantees that xprtrdma cannot overflow the Send Queue, so remove the remaining bits of the original Send WQE counting mechanism. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17xprtrdma: RPC completion should wait for Send completionChuck Lever
When an RPC Call includes a file data payload, that payload can come from pages in the page cache, or a user buffer (for direct I/O). If the payload can fit inline, xprtrdma includes it in the Send using a scatter-gather technique. xprtrdma mustn't allow the RPC consumer to re-use the memory where that payload resides before the Send completes. Otherwise, the new contents of that memory would be exposed by an HCA retransmit of the Send operation. So, block RPC completion on Send completion, but only in the case where a separate file data payload is part of the Send. This prevents the reuse of that memory while it is still part of a Send operation without an undue cost to other cases. Waiting is avoided in the common case because typically the Send will have completed long before the RPC Reply arrives. These days, an RPC timeout will trigger a disconnect, which tears down the QP. The disconnect flushes all waiting Sends. This bounds the amount of time the reply handler has to wait for a Send completion. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17xprtrdma: Refactor rpcrdma_deferred_completionChuck Lever
Invoke a common routine for releasing hardware resources (for example, invalidating MRs). This needs to be done whether an RPC Reply has arrived or the RPC was terminated early. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17xprtrdma: Add a field of bit flags to struct rpcrdma_reqChuck Lever
We have one boolean flag in rpcrdma_req today. I'd like to add more flags, so convert that boolean to a bit flag. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17xprtrdma: Add data structure to manage RDMA Send argumentsChuck Lever
Problem statement: Recently Sagi Grimberg <sagi@grimberg.me> observed that kernel RDMA- enabled storage initiators don't handle delayed Send completion correctly. If Send completion is delayed beyond the end of a ULP transaction, the ULP may release resources that are still being used by the HCA to complete a long-running Send operation. This is a common design trait amongst our initiators. Most Send operations are faster than the ULP transaction they are part of. Waiting for a completion for these is typically unnecessary. Infrequently, a network partition or some other problem crops up where an ordering problem can occur. In NFS parlance, the RPC Reply arrives and completes the RPC, but the HCA is still retrying the Send WR that conveyed the RPC Call. In this case, the HCA can try to use memory that has been invalidated or DMA unmapped, and the connection is lost. If that memory has been re-used for something else (possibly not related to NFS), and the Send retransmission exposes that data on the wire. Thus we cannot assume that it is safe to release Send-related resources just because a ULP reply has arrived. After some analysis, we have determined that the completion housekeeping will not be difficult for xprtrdma: - Inline Send buffers are registered via the local DMA key, and are already left DMA mapped for the lifetime of a transport connection, thus no additional handling is necessary for those - Gathered Sends involving page cache pages _will_ need to DMA unmap those pages after the Send completes. But like inline send buffers, they are registered via the local DMA key, and thus will not need to be invalidated In addition, RPC completion will need to wait for Send completion in the latter case. However, nearly always, the Send that conveys the RPC Call will have completed long before the RPC Reply arrives, and thus no additional latency will be accrued. Design notes: In this patch, the rpcrdma_sendctx object is introduced, and a lock-free circular queue is added to manage a set of them per transport. The RPC client's send path already prevents sending more than one RPC Call at the same time. This allows us to treat the consumer side of the queue (rpcrdma_sendctx_get_locked) as if there is a single consumer thread. The producer side of the queue (rpcrdma_sendctx_put_locked) is invoked only from the Send completion handler, which is a single thread of execution (soft IRQ). The only care that needs to be taken is with the tail index, which is shared between the producer and consumer. Only the producer updates the tail index. The consumer compares the head with the tail to ensure that the a sendctx that is in use is never handed out again (or, expressed more conventionally, the queue is empty). When the sendctx queue empties completely, there are enough Sends outstanding that posting more Send operations can result in a Send Queue overflow. In this case, the ULP is told to wait and try again. This introduces strong Send Queue accounting to xprtrdma. As a final touch, Jason Gunthorpe <jgunthorpe@obsidianresearch.com> suggested a mechanism that does not require signaling every Send. We signal once every N Sends, and perform SGE unmapping of N Send operations during that one completion. Reported-by: Sagi Grimberg <sagi@grimberg.me> Suggested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17xprtrdma: "Unoptimize" rpcrdma_prepare_hdr_sge()Chuck Lever
Commit 655fec6987be ("xprtrdma: Use gathered Send for large inline messages") assumed that, since the zeroeth element of the Send SGE array always pointed to req->rl_rdmabuf, it needed to be initialized just once. This was a valid assumption because the Send SGE array and rl_rdmabuf both live in the same rpcrdma_req. In a subsequent patch, the Send SGE array will be separated from the rpcrdma_req, so the zeroeth element of the SGE array needs to be initialized every time. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17xprtrdma: Change return value of rpcrdma_prepare_send_sges()Chuck Lever
Clean up: Make rpcrdma_prepare_send_sges() return a negative errno instead of a bool. Soon callers will want distinct treatments of different types of failures. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17xprtrdma: Fix error handling in rpcrdma_prepare_msg_sges()Chuck Lever
When this function fails, it needs to undo the DMA mappings it's done so far. Otherwise these are leaked. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17xprtrdma: Clean up SGE accounting in rpcrdma_prepare_msg_sges()Chuck Lever
Clean up. rpcrdma_prepare_hdr_sge() sets num_sge to one, then rpcrdma_prepare_msg_sges() sets num_sge again to the count of SGEs it added, plus one for the header SGE just mapped in rpcrdma_prepare_hdr_sge(). This is confusing, and nails in an assumption about when these functions are called. Instead, maintain a running count that both functions can update with just the number of SGEs they have added to the SGE array. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-11-17xprtrdma: Decode credits field in rpcrdma_reply_handlerChuck Lever
We need to decode and save the incoming rdma_credits field _after_ we know that the direction of the message is "forward direction Reply". Otherwise, the credits value in reverse direction Calls is also used to update the forward direction credits. It is safe to decode the rdma_credits field in rpcrdma_reply_handler now that rpcrdma_reply_handler is single-threaded. Receives complete in the same order as they were sent on the NFS server. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>