linux/net/sunrpc
Chuck Lever 4757d90b15 svcrdma: Report Write/Reply chunk overruns
Observed at Connectathon 2017.

If a client has underestimated the size of a Write or Reply chunk,
the Linux server writes as much payload data as it can, then it
recognizes there was a problem and closes the connection without
sending the transport header.

This creates a couple of problems:

<> The client never receives indication of the server-side failure,
   so it continues to retransmit the bad RPC. Forward progress on
   the transport is blocked.

<> The reply payload pages are not moved out of the svc_rqst, thus
   they can be released by the RPC server before the RDMA Writes
   have completed.

The new rdma_rw-ized helpers return a distinct error code when a
Write/Reply chunk overrun occurs, so it's now easy for the caller
(svc_rdma_sendto) to recognize this case.

Instead of dropping the connection, post an RDMA_ERROR message. The
client now sees an RDMA_ERROR and can properly terminate the RPC
transaction.

As part of the new logic, set up the same delayed release for these
payload pages as would have occurred in the normal case.

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>
2017-04-25 17:25:55 -04:00
..
auth_gss The nfsd update this round is mainly a lot of miscellaneous cleanups and 2017-02-28 15:39:09 -08:00
xprtrdma svcrdma: Report Write/Reply chunk overruns 2017-04-25 17:25:55 -04:00
addr.c replace strict_strto calls 2014-07-12 18:45:49 -04:00
auth_generic.c NFS client updates for Linux 4.9 2016-10-13 21:28:20 -07:00
auth_null.c sunrpc: remove dead codes of cr_magic in rpc_cred 2017-02-08 17:02:46 -05:00
auth_unix.c sunrpc: rename NFS_NGROUPS to UNX_NGROUPS for auth unix 2017-02-08 17:02:45 -05:00
auth.c sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h> 2017-03-02 08:42:31 +01:00
backchannel_rqst.c SUNRPC: Refactor rpc_xdr_buf_init() 2016-09-19 13:08:37 -04:00
cache.c NFS client updates for Linux 4.11 2017-03-01 16:10:30 -08:00
clnt.c NFSv4: Set the connection timeout to match the lease period 2017-02-09 14:15:16 -05:00
debugfs.c sunrpc: record rpc client pointer in seq->private directly 2017-02-08 17:02:47 -05:00
Kconfig svcrdma: Introduce local rdma_rw API helpers 2017-04-25 17:25:55 -04:00
Makefile SUNRPC: Add a structure to track multiple transports 2016-02-05 18:48:54 -05:00
netns.h netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
rpc_pipe.c fs: Replace CURRENT_TIME with current_time() for inode timestamps 2016-09-27 21:06:21 -04:00
rpcb_clnt.c SUNRPC: Use the multipath iterator to assign a transport to each task 2016-02-05 18:48:55 -05:00
sched.c SUNRPC: Separate buffer pointers for RPC Call and Reply messages 2016-09-19 13:08:37 -04:00
socklib.c sunrpc: do not pull udp headers on receive 2016-04-11 15:31:33 -04:00
stats.c SUNRPC: Proper metric accounting when RPC is not transmitted 2016-11-29 16:45:44 -05:00
sunrpc_syms.c SUNRPC: cleanup ida information when removing sunrpc module 2017-01-24 15:29:24 -05:00
sunrpc.h SUNRPC: track whether a request is coming from a loop-back interface. 2014-05-22 15:59:18 -04:00
svc_xprt.c Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-02-20 13:23:30 -08:00
svc.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h> 2017-03-02 08:42:29 +01:00
svcauth_unix.c sunrpc: rename NFS_NGROUPS to UNX_NGROUPS for auth unix 2017-02-08 17:02:45 -05:00
svcauth.c locking/atomic, kref: Implement kref_put_lock() 2017-01-18 10:03:29 +01:00
svcsock.c SUNRPC/backchanel: set XPT_CONG_CTRL flag for bc xprt 2017-03-09 15:20:46 -05:00
sysctl.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
timer.c
xdr.c SUNRPC: Add a helper function xdr_stream_decode_string_dup() 2017-02-21 16:56:16 -05:00
xprt.c sunrpc: Allow xprt->ops->timer method to sleep 2017-02-10 14:02:37 -05:00
xprtmultipath.c SUNRPC search xprt switch for sockaddr 2016-09-19 13:08:36 -04:00
xprtsock.c NFS client updates for Linux 4.11 2017-03-01 16:10:30 -08:00