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* NFS: Don't drop CB requests with invalid principalsChuck Lever2016-07-111-0/+5
| | | | | | | | | | | | | | Before commit 778be232a207 ("NFS do not find client in NFSv4 pg_authenticate"), the Linux callback server replied with RPC_AUTH_ERROR / RPC_AUTH_BADCRED, instead of dropping the CB request. Let's restore that behavior so the server has a chance to do something useful about it, and provide a warning that helps admins correct the problem. Fixes: 778be232a207 ("NFS do not find client in NFSv4 ...") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* svc: Avoid garbage replies when pc_func() returns rpc_drop_replyChuck Lever2016-07-111-1/+2
| | | | | | | | | | | | If an RPC program does not set vs_dispatch and pc_func() returns rpc_drop_reply, the server sends a reply anyway containing a single word containing the value RPC_DROP_REPLY (in network byte-order, of course). This is a nonsense RPC message. Fixes: 9e701c610923 ("svcrpc: simpler request dropping") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: No direct data placement with krb5i and krb5pChuck Lever2016-07-114-2/+26
| | | | | | | | | | | | | | | | | | | | Direct data placement is not allowed when using flavors that guarantee integrity or privacy. When such security flavors are in effect, don't allow the use of Read and Write chunks for moving individual data items. All messages larger than the inline threshold are sent via Long Call or Long Reply. On my systems (CX-3 Pro on FDR), for small I/O operations, the use of Long messages adds only around 5 usecs of latency in each direction. Note that when integrity or encryption is used, the host CPU touches every byte in these messages. Even if it could be used, data movement offload doesn't buy much in this case. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Clean up fixup_copy_count accountingChuck Lever2016-07-111-13/+13
| | | | | | | | | | | | | | fixup_copy_count should count only the number of bytes copied to the page list. The head and tail are now always handled without a data copy. And the debugging at the end of rpcrdma_inline_fixup() is also no longer necessary, since copy_len will be non-zero when there is reply data in the tail (a normal and valid case). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Update only specific fields in private receive bufferChuck Lever2016-07-111-4/+9
| | | | | | | | | | | Now that rpcrdma_inline_fixup() updates only two fields in rq_rcv_buf, a full memcpy of that structure to rq_private_buf is unwarranted. Updating rq_private_buf fields only where needed also better documents what is going on. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Do not update {head, tail}.iov_len in rpcrdma_inline_fixup()Chuck Lever2016-07-111-28/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While trying NFSv4.0/RDMA with sec=krb5p, I noticed small NFS READ operations failed. After the client unwrapped the NFS READ reply message, the NFS READ XDR decoder was not able to decode the reply. The message was "Server cheating in reply", with the reported number of received payload bytes being zero. Applications reported a read(2) that returned -1/EIO. The problem is rpcrdma_inline_fixup() sets the tail.iov_len to zero when the incoming reply fits entirely in the head iovec. The zero tail.iov_len confused xdr_buf_trim(), which then mangled the actual reply data instead of simply removing the trailing GSS checksum. As near as I can tell, RPC transports are not supposed to update the head.iov_len, page_len, or tail.iov_len fields in the receive XDR buffer when handling an incoming RPC reply message. These fields contain the length of each component of the XDR buffer, and hence the maximum number of bytes of reply data that can be stored in each XDR buffer component. I've concluded this because: - This is how xdr_partial_copy_from_skb() appears to behave - rpcrdma_inline_fixup() already does not alter page_len - call_decode() compares rq_private_buf and rq_rcv_buf and WARNs if they are not exactly the same Unfortunately, as soon as I tried the simple fix to just remove the line that sets tail.iov_len to zero, I saw that the logic that appends the implicit Write chunk pad inline depends on inline_fixup setting tail.iov_len to zero. To address this, re-organize the tail iovec handling logic to use the same approach as with the head iovec: simply point tail.iov_base to the correct bytes in the receive buffer. While I remember all this, write down the conclusion in documenting comments. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: rpcrdma_inline_fixup() overruns the receive page listChuck Lever2016-07-111-5/+11
| | | | | | | | | | When the remaining length of an incoming reply is longer than the XDR buf's page_len, switch over to the tail iovec instead of copying more than page_len bytes into the page list. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Chunk list encoders no longer share one rl_segments arrayChuck Lever2016-07-112-53/+44Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, all three chunk list encoders each use a portion of the one rl_segments array in rpcrdma_req. This is because the MWs for each chunk list were preserved in rl_segments so that ro_unmap could find and invalidate them after the RPC was complete. However, now that MWs are placed on a per-req linked list as they are registered, there is no longer any information in rpcrdma_mr_seg that is shared between ro_map and ro_unmap_{sync,safe}, and thus nothing in rl_segments needs to be preserved after rpcrdma_marshal_req is complete. Thus the rl_segments array can be used now just for the needs of each rpcrdma_convert_iovs call. Once each chunk list is encoded, the next chunk list encoder is free to re-use all of rl_segments. This means all three chunk lists in one RPC request can now each encode a full size data payload with no increase in the size of rl_segments. This is a key requirement for Kerberos support, since both the Call and Reply for a single RPC transaction are conveyed via Long messages (RDMA Read/Write). Both can be large. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Place registered MWs on a per-req listChuck Lever2016-07-116-139/+94Star
| | | | | | | | | | | | | | | | | | | Instead of placing registered MWs sparsely into the rl_segments array, place these MWs on a per-req list. ro_unmap_{sync,safe} can then simply pull those MWs off the list instead of walking through the array. This change significantly reduces the size of struct rpcrdma_req by removing nsegs and rl_mw from every array element. As an additional clean-up, chunk co-ordinates are returned in the "*mw" output argument so they are no longer needed in every array element. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Release orphaned MRs immediatelyChuck Lever2016-07-112-12/+26
| | | | | | | | | | Instead of leaving orphaned MRs to be released when the transport is destroyed, release them immediately. The MR free list can now be replenished if it becomes exhausted. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Allocate MRs on demandChuck Lever2016-07-115-124/+114Star
| | | | | | | | | | | | | | | | | | | | | | | | | Frequent MR list exhaustion can impact I/O throughput, so enough MRs are always created during transport set-up to prevent running out. This means more MRs are created than most workloads need. Commit 94f58c58c0b4 ("xprtrdma: Allow Read list and Reply chunk simultaneously") introduced support for sending two chunk lists per RPC, which consumes more MRs per RPC. Instead of trying to provision more MRs, introduce a mechanism for allocating MRs on demand. A few MRs are allocated during transport set-up to kick things off. This significantly reduces the average number of MRs per transport while allowing the MR count to grow for workloads or devices that need more MRs. FRWR with mlx4 allocated almost 400 MRs per transport before this patch. Now it starts with 32. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Chunk list encoders must not return zeroChuck Lever2016-07-113-3/+7
| | | | | | | | | | Clean up, based on code audit: Remove the possibility that the chunk list XDR encoders can return zero, which would be interpreted as a NULL. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Honor ->send_request API contractChuck Lever2016-07-115-24/+39
| | | | | | | | | | | | | | | | | | | | | Commit c93c62231cf5 ("xprtrdma: Disconnect on registration failure") added a disconnect for some RPC marshaling failures. This is needed only in a handful of cases, but it was triggering for simple stuff like temporary resource shortages. Try to straighten this out. Fix up the lower layers so they don't return -ENOMEM or other error codes that the RPC client's FSM doesn't explicitly recognize. Also fix up the places in the send_request path that do want a disconnect. For example, when ib_post_send or ib_post_recv fail, this is a sign that there is a send or receive queue resource miscalculation. That should be rare, and is a sign of a software bug. But xprtrdma can recover: disconnect to reset the transport and start over. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Reply buffer exhaustion can be catastrophicChuck Lever2016-07-111-7/+5Star
| | | | | | | | | | | | | | | Not having an rpcrdma_rep at call_allocate time can be a problem. It means that send_request can't post a receive buffer to catch the RPC's reply. Possible consequences are RPC timeouts or even transport deadlock. Instead of allowing an RPC to proceed if an rpcrdma_rep is not available, return NULL to force call_allocate to wait and try again. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Clean up device capability detectionChuck Lever2016-07-114-29/+44
| | | | | | | | | Clean up: Move device capability detection into memreg-specific source files. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Remove rpcrdma_map_one() and friendsChuck Lever2016-07-112-44/+0Star
| | | | | | | | | | | | | Clean up: ALLPHYSICAL is gone and FMR has been converted to use scatterlists. There are no more users of these functions. This patch shrinks the size of struct rpcrdma_req by about 3500 bytes on x86_64. There is one of these structs for each RPC credit (128 credits per transport connection). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Remove ALLPHYSICAL memory registration modeChuck Lever2016-07-114-142/+2Star
| | | | | | | | | | | | | | | | | | | | | | | | | | No HCA or RNIC in the kernel tree requires the use of ALLPHYSICAL. ALLPHYSICAL advertises in the clear on the network fabric an R_key that is good for all of the client's memory. No known exploit exists, but theoretically any user on the server can use that R_key on the client's QP to read or update any part of the client's memory. ALLPHYSICAL exposes the client to server bugs, including: o base/bounds errors causing data outside the i/o buffer to be accessed o RDMA access after reply causing data corruption and/or integrity fail ALLPHYSICAL can't protect application memory regions from server update after a local signal or soft timeout has terminated an RPC. ALLPHYSICAL chunks are no larger than a page. Special cases to handle small chunks and long chunk lists have been a source of implementation complexity and bugs. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Do not leak an MW during a DMA map failureChuck Lever2016-07-112-0/+2
| | | | | | | | Based on code audit. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Refactor MR recovery work queuesChuck Lever2016-07-115-166/+135Star
| | | | | | | | | | | | | | | | I found that commit ead3f26e359e ("xprtrdma: Add ro_unmap_safe memreg method"), which introduces ro_unmap_safe, never wired up the FMR recovery worker. The FMR and FRWR recovery work queues both do the same thing. Instead of setting up separate individual work queues for this, schedule a delayed worker to deal with them, since recovering MRs is not performance-critical. Fixes: ead3f26e359e ("xprtrdma: Add ro_unmap_safe memreg method") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Use scatterlist for DMA mapping and unmapping under FMRChuck Lever2016-07-111-39/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The use of a scatterlist for handling DMA mapping and unmapping was recently introduced in frwr_ops.c in commit 4143f34e01e9 ("xprtrdma: Port to new memory registration API"). That commit did not make a similar update to xprtrdma's FMR support because the core ib_map_phys_fmr() and ib_unmap_fmr() APIs have not been changed to take a scatterlist argument. However, FMR still needs to do DMA mapping and unmapping. It appears that RDS, for example, uses a scatterlist for this, then builds the DMA addr array for the ib_map_phys_fmr call separately. I see that SRP also utilizes a scatterlist for DMA mapping. xprtrdma can do something similar. This modernization is used immediately to properly defer DMA unmapping during fmr_unmap_safe (a FIXME). It separates the DMA unmapping coordinates from the rl_segments array. This array, being part of an rpcrdma_req, is always re-used immediately when an RPC exits. A scatterlist is allocated in memory independent of the rl_segments array, so it can be preserved indefinitely (ie, until the MR invalidation and DMA unmapping can actually be done by a worker thread). The FRWR and FMR DMA mapping code are slightly different from each other now, and will diverge further when the "Check for holes" logic can be removed from FRWR (support for SG_GAP MRs). So I chose not to create helpers for the common-looking code. Fixes: ead3f26e359e ("xprtrdma: Add ro_unmap_safe memreg method") Suggested-by: Sagi Grimberg <sagi@lightbits.io> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Rename fields in rpcrdma_fmrChuck Lever2016-07-112-19/+19
| | | | | | | | | Clean up: Use the same naming convention used in other RPC/RDMA-related data structures. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Move init and release helpersChuck Lever2016-07-112-89/+119
| | | | | | | | | Clean up: Moving these helpers in a separate patch makes later patches more readable. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Create common scatterlist fields in rpcrdma_mwChuck Lever2016-07-112-47/+46Star
| | | | | | | | | | | | | | Clean up: FMR is about to replace the rpcrdma_map_one code with scatterlists. Move the scatterlist fields out of the FRWR-specific union and into the generic part of rpcrdma_mw. One minor change: -EIO is now returned if FRWR registration fails. The RPC is terminated immediately, since the problem is likely due to a software bug, thus retrying likely won't help. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* xprtrdma: Remove FMRs from the unmap list after unmappingChuck Lever2016-07-111-2/+7
| | | | | | | | | | | | | | | | | | | | | | ib_unmap_fmr() takes a list of FMRs to unmap. However, it does not remove the FMRs from this list as it processes them. Other ib_unmap_fmr() call sites are careful to remove FMRs from the list after ib_unmap_fmr() returns. Since commit 7c7a5390dc6c8 ("xprtrdma: Add ro_unmap_sync method for FMR") fmr_op_unmap_sync passes more than one FMR to ib_unmap_fmr(), but it didn't bother to remove the FMRs from that list once the call was complete. I've noticed some instability that could be related to list tangling by the new fmr_op_unmap_sync() logic. In an abundance of caution, add some defensive logic to clean up properly after ib_unmap_fmr(). Fixes: 7c7a5390dc6c8 ("xprtrdma: Add ro_unmap_sync method for FMR") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* rpc: share one xps between all backchannelsJ. Bruce Fields2016-06-153-4/+17
| | | | | | | | | | | | The spec allows backchannels for multiple clients to share the same tcp connection. When that happens, we need to use the same xprt for all of them. Similarly, we need the same xps. This fixes list corruption introduced by the multipath code. Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com> Acked-by: Trond Myklebust <trondmy@primarydata.com>
* nfsd4/rpc: move backchannel create logic into rpc codeJ. Bruce Fields2016-06-151-2/+10
| | | | | | | | Also simplify the logic a bit. Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com> Acked-by: Trond Myklebust <trondmy@primarydata.com>
* SUNRPC: fix xprt leak on xps allocation failureJ. Bruce Fields2016-06-151-2/+3
| | | | | | | | | Callers of rpc_create_xprt expect it to put the xprt on success and failure. Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com> Acked-by: Trond Myklebust <trondmy@primarydata.com>
* Merge tag 'nfs-for-4.7-1' of git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds2016-05-2615-444/+676
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull NFS client updates from Anna Schumaker: "Highlights include: Features: - Add support for the NFS v4.2 COPY operation - Add support for NFS/RDMA over IPv6 Bugfixes and cleanups: - Avoid race that crashes nfs_init_commit() - Fix oops in callback path - Fix LOCK/OPEN race when unlinking an open file - Choose correct stateids when using delegations in setattr, read and write - Don't send empty SETATTR after OPEN_CREATE - xprtrdma: Prevent server from writing a reply into memory client has released - xprtrdma: Support using Read list and Reply chunk in one RPC call" * tag 'nfs-for-4.7-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (61 commits) pnfs: pnfs_update_layout needs to consider if strict iomode checking is on nfs/flexfiles: Use the layout segment for reading unless it a IOMODE_RW and reading is disabled nfs/flexfiles: Helper function to detect FF_FLAGS_NO_READ_IO nfs: avoid race that crashes nfs_init_commit NFS: checking for NULL instead of IS_ERR() in nfs_commit_file() pnfs: make pnfs_layout_process more robust pnfs: rework LAYOUTGET retry handling pnfs: lift retry logic from send_layoutget to pnfs_update_layout pnfs: fix bad error handling in send_layoutget flexfiles: add kerneldoc header to nfs4_ff_layout_prepare_ds flexfiles: remove pointless setting of NFS_LAYOUT_RETURN_REQUESTED pnfs: only tear down lsegs that precede seqid in LAYOUTRETURN args pnfs: keep track of the return sequence number in pnfs_layout_hdr pnfs: record sequence in pnfs_layout_segment when it's created pnfs: don't merge new ff lsegs with ones that have LAYOUTRETURN bit set pNFS/flexfiles: When initing reads or writes, we might have to retry connecting to DSes pNFS/flexfiles: When checking for available DSes, conditionally check for MDS io pNFS/flexfile: Fix erroneous fall back to read/write through the MDS NFS: Reclaim writes via writepage are opportunistic NFSv4: Use the right stateid for delegations in setattr, read and write ...
| * SUNRPC: Ensure get_rpccred() and put_rpccred() can take NULL argumentsTrond Myklebust2016-05-171-2/+3
| | | | | | | | | | Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Remove qplockChuck Lever2016-05-172-4/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | Clean up. After "xprtrdma: Remove ro_unmap() from all registration modes", there are no longer any sites that take rpcrdma_ia::qplock for read. The one site that takes it for write is always single-threaded. It is safe to remove it. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Faster server reboot recoveryChuck Lever2016-05-171-1/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In a cluster failover scenario, it is desirable for the client to attempt to reconnect quickly, as an alternate NFS server is already waiting to take over for the down server. The client can't see that a server IP address has moved to a new server until the existing connection is gone. For fabrics and devices where it is meaningful, set a definite upper bound on the amount of time before it is determined that a connection is no longer valid. This allows the RPC client to detect connection loss in a timely matter, then perform a fresh resolution of the server GUID in case it has changed (cluster failover). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Remove ro_unmap() from all registration modesChuck Lever2016-05-174-88/+0Star
| | | | | | | | | | | | | | | | | | Clean up: The ro_unmap method is no longer used. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Add ro_unmap_safe memreg methodChuck Lever2016-05-176-19/+150
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There needs to be a safe method of releasing registered memory resources when an RPC terminates. Safe can mean a number of things: + Doesn't have to sleep + Doesn't rely on having a QP in RTS ro_unmap_safe will be that safe method. It can be used in cases where synchronous memory invalidation can deadlock, or needs to have an active QP. The important case is fencing an RPC's memory regions after it is signaled (^C) and before it exits. If this is not done, there is a window where the server can write an RPC reply into memory that the client has released and re-used for some other purpose. Note that this is a full solution for FRWR, but FMR and physical still have some gaps where a particularly bad server can wreak some havoc on the client. These gaps are not made worse by this patch and are expected to be exceptionally rare and timing-based. They are noted in documenting comments. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Refactor __fmr_dma_unmap()Chuck Lever2016-05-171-5/+2Star
| | | | | | | | | | | | | | | | | | | | | | | | Separate the DMA unmap operation from freeing the MW. In a subsequent patch they will not always be done at the same time, and they are not related operations (except by order; freeing the MW must be the last step during invalidation). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Move fr_xprt and fr_worker to struct rpcrdma_mwChuck Lever2016-05-172-7/+7
| | | | | | | | | | | | | | | | | | | | | | In a subsequent patch, the fr_xprt and fr_worker fields will be needed by another memory registration mode. Move them into the generic rpcrdma_mw structure that wraps struct rpcrdma_frmr. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Refactor the FRWR recovery workerChuck Lever2016-05-171-9/+16
| | | | | | | | | | | | | | | | | | | | Maintain the order of invalidation and DMA unmapping when doing a background MR reset. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Reset MRs in frwr_op_unmap_sync()Chuck Lever2016-05-171-38/+60
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | frwr_op_unmap_sync() is now invoked in a workqueue context, the same as __frwr_queue_recovery(). There's no need to defer MR reset if posting LOCAL_INV MRs fails. This means that even when ib_post_send() fails (which should occur very rarely) the invalidation and DMA unmapping steps are still done in the correct order. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Save I/O direction in struct rpcrdma_frwrChuck Lever2016-05-172-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the the I/O direction field from rpcrdma_mr_seg into the rpcrdma_frmr. This makes it possible to DMA-unmap the frwr long after an RPC has exited and its rpcrdma_mr_seg array has been released and re-used. This might occur if an RPC times out while waiting for a new connection to be established. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Rename rpcrdma_frwr::sg and sg_nentsChuck Lever2016-05-172-20/+20
| | | | | | | | | | | | | | | | | | | | Clean up: Follow same naming convention as other fields in struct rpcrdma_frwr. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Use core ib_drain_qp() APIChuck Lever2016-05-171-35/+6Star
| | | | | | | | | | | | | | | | | | | | | | Clean up: Replace rpcrdma_flush_cqs() and rpcrdma_clean_cqs() with the new ib_drain_qp() API. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-By: Leon Romanovsky <leonro@mellanox.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Remove rpcrdma_create_chunks()Chuck Lever2016-05-171-151/+0Star
| | | | | | | | | | | | | | | | | | rpcrdma_create_chunks() has been replaced, and can be removed. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Allow Read list and Reply chunk simultaneouslyChuck Lever2016-05-172-60/+272
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | rpcrdma_marshal_req() makes a simplifying assumption: that NFS operations with large Call messages have small Reply messages, and vice versa. Therefore with RPC-over-RDMA, only one chunk type is ever needed for each Call/Reply pair, because one direction needs chunks, the other direction will always fit inline. In fact, this assumption is asserted in the code: if (rtype != rpcrdma_noch && wtype != rpcrdma_noch) { dprintk("RPC: %s: cannot marshal multiple chunk lists\n", __func__); return -EIO; } But RPCGSS_SEC breaks this assumption. Because krb5i and krb5p perform data transformation on RPC messages before they are transmitted, direct data placement techniques cannot be used, thus RPC messages must be sent via a Long call in both directions. All such calls are sent with a Position Zero Read chunk, and all such replies are handled with a Reply chunk. Thus the client must provide every Call/Reply pair with both a Read list and a Reply chunk. Without any special security in effect, NFSv4 WRITEs may now also use the Read list and provide a Reply chunk. The marshal_req logic was preventing that, meaning an NFSv4 WRITE with a large payload that included a GETATTR result larger than the inline threshold would fail. The code that encodes each chunk list is now completely contained in its own function. There is some code duplication, but the trade-off is that the overall logic should be more clear. Note that all three chunk lists now share the rl_segments array. Some additional per-req accounting is necessary to track this usage. For the same reasons that the above simplifying assumption has held true for so long, I don't expect more array elements are needed at this time. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Update comments in rpcrdma_marshal_req()Chuck Lever2016-05-171-14/+4Star
| | | | | | | | | | | | | | | | | | | | Update documenting comments to reflect code changes over the past year. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Avoid using Write list for small NFS READ requestsChuck Lever2016-05-171-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Avoid the latency and interrupt overhead of registering a Write chunk when handling NFS READ requests of a few hundred bytes or less. This change does not interoperate with Linux NFS/RDMA servers that do not have commit 9d11b51ce7c1 ('svcrdma: Fix send_reply() scatter/gather set-up'). Commit 9d11b51ce7c1 was introduced in v4.3, and is included in 4.2.y, 4.1.y, and 3.18.y. Oracle bug 22925946 has been filed to request that the above fix be included in the Oracle Linux UEK4 NFS/RDMA server. Red Hat bugzillas 1327280 and 1327554 have been filed to request that RHEL NFS/RDMA server backports include the above fix. Workaround: Replace the "proto=rdma,port=20049" mount options with "proto=tcp" until commit 9d11b51ce7c1 is applied to your NFS server. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Prevent inline overflowChuck Lever2016-05-175-11/+90
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When deciding whether to send a Call inline, rpcrdma_marshal_req doesn't take into account header bytes consumed by chunk lists. This results in Call messages on the wire that are sometimes larger than the inline threshold. Likewise, when a Write list or Reply chunk is in play, the server's reply has to emit an RDMA Send that includes a larger-than-minimal RPC-over-RDMA header. The actual size of a Call message cannot be estimated until after the chunk lists have been registered. Thus the size of each RPC-over-RDMA header can be estimated only after chunks are registered; but the decision to register chunks is based on the size of that header. Chicken, meet egg. The best a client can do is estimate header size based on the largest header that might occur, and then ensure that inline content is always smaller than that. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Limit number of RDMA segments in RPC-over-RDMA headersChuck Lever2016-05-175-26/+23Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Send buffer space is shared between the RPC-over-RDMA header and an RPC message. A large RPC-over-RDMA header means less space is available for the associated RPC message, which then has to be moved via an RDMA Read or Write. As more segments are added to the chunk lists, the header increases in size. Typical modern hardware needs only a few segments to convey the maximum payload size, but some devices and registration modes may need a lot of segments to convey data payload. Sometimes so many are needed that the remaining space in the Send buffer is not enough for the RPC message. Sending such a message usually fails. To ensure a transport can always make forward progress, cap the number of RDMA segments that are allowed in chunk lists. This prevents less-capable devices and memory registrations from consuming a large portion of the Send buffer by reducing the maximum data payload that can be conveyed with such devices. For now I choose an arbitrary maximum of 8 RDMA segments. This allows a maximum size RPC-over-RDMA header to fit nicely in the current 1024 byte inline threshold with over 700 bytes remaining for an inline RPC message. The current maximum data payload of NFS READ or WRITE requests is one megabyte. To convey that payload on a client with 4KB pages, each chunk segment would need to handle 32 or more data pages. This is well within the capabilities of FMR. For physical registration, the maximum payload size on platforms with 4KB pages is reduced to 32KB. For FRWR, a device's maximum page list depth would need to be at least 34 to support the maximum 1MB payload. A device with a smaller maximum page list depth means the maximum data payload is reduced when using that device. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * xprtrdma: Bound the inline threshold valuesChuck Lever2016-05-171-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the sysctls that allow setting the inline threshold allow any value to be set. Small values only make the transport run slower. The default 1KB setting is as low as is reasonable. And the logic that decides how to divide a Send buffer between RPC-over-RDMA header and RPC message assumes (but does not check) that the lower bound is not crazy (say, 57 bytes). Send and receive buffers share a page with some control information. Values larger than about 3KB can't be supported, currently. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * sunrpc: Advertise maximum backchannel payload sizeChuck Lever2016-05-175-0/+41
| | | | | | | | | | | | | | | | | | | | RPC-over-RDMA transports have a limit on how large a backward direction (backchannel) RPC message can be. Ensure that the NFSv4.x CREATE_SESSION operation advertises this limit to servers. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * sunrpc: add rpc_lookup_generic_credWeston Andros Adamson2016-05-091-0/+7
| | | | | | | | | | | | | | | | | | | | Add function rpc_lookup_generic_cred, which allows lookups of a generic credential that's not current_cred(). [jlayton: add gfp_t parm] Signed-off-by: Jeff Layton <jeff.layton@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * sunrpc: plumb gfp_t parm into crcreate operationJeff Layton2016-05-094-11/+11
| | | | | | | | | | | | | | | | | | | | We need to be able to call the generic_cred creator from different contexts. Add a gfp_t parm to the crcreate operation and to rpcauth_lookup_credcache. For now, we just push the gfp_t parms up one level to the *_lookup_cred functions. Signed-off-by: Jeff Layton <jeff.layton@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>