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2015-09-19SUNRPC: xs_sock_mark_closed() does not need to trigger socket autocloseTrond Myklebust1-1/+0
Under all conditions, it should be quite sufficient just to mark the socket as disconnected. It will then be closed by the transport shutdown or reconnect code. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-09-17SUNRPC: Ensure that we wait for connections to complete before retryingTrond Myklebust1-3/+8
Commit 718ba5b87343, moved the responsibility for unlocking the socket to xs_tcp_setup_socket, meaning that the socket will be unlocked before we know that it has finished trying to connect. The following patch is based on an initial patch by Russell King to ensure that we delay clearing the XPRT_CONNECTING flag until we either know that we failed to initiate a connection attempt, or the connection attempt itself failed. Fixes: 718ba5b87343 ("SUNRPC: Add helpers to prevent socket create from racing") Reported-by: Russell King <linux@arm.linux.org.uk> Reported-by: Russell King <rmk+kernel@arm.linux.org.uk> Tested-by: Russell King <rmk+kernel@arm.linux.org.uk> Tested-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-09-17SUNRPC: Fix races between socket connection and destroy codeTrond Myklebust1-0/+3
When we're destroying the socket transport, we need to ensure that we cancel any existing delayed connection attempts, and order them w.r.t. the call to xs_close(). Reported-by:"Suzuki K. Poulose" <suzuki.poulose@arm.com> Acked-by: Jeff Layton <jlayton@poochiereds.net> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-08-29SUNRPC: Prevent SYN+SYNACK+RST stormsTrond Myklebust1-0/+2
Add a shutdown() call before we release the socket in order to ensure the reset is sent before we try to reconnect. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-08-29SUNRPC: xs_reset_transport must mark the connection as disconnectedTrond Myklebust1-0/+1
In case the reconnection attempt fails. Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-08-19SUNRPC: Allow sockets to do GFP_NOIO allocationsTrond Myklebust1-3/+3
Follow up to commit c4a7ca774949 ("SUNRPC: Allow waiting on memory allocation"). Allows the RPC socket code to do non-IO blocking. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-08-17SUNRPC: Fix a thinko in xs_connect()Trond Myklebust1-4/+5
It is rather pointless to test the value of transport->inet after calling xs_reset_transport(), since it will always be zero, and so we will never see any exponential back off behaviour. Also don't force early connections for SOFTCONN tasks. If the server disconnects us, we should respect the exponential backoff. Cc: stable@vger.kernel.org # 4.0+ Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-28Merge tag 'nfs-for-4.2-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds1-8/+17
Pull NFS client bugfixes from Trond Myklebust: "Highlights include: Stable patches: - Fix a situation where the client uses the wrong (zero) stateid. - Fix a memory leak in nfs_do_recoalesce Bugfixes: - Plug a memory leak when ->prepare_layoutcommit fails - Fix an Oops in the NFSv4 open code - Fix a backchannel deadlock - Fix a livelock in sunrpc when sendmsg fails due to low memory availability - Don't revalidate the mapping if both size and change attr are up to date - Ensure we don't miss a file extension when doing pNFS - Several fixes to handle NFSv4.1 sequence operation status bits correctly - Several pNFS layout return bugfixes" * tag 'nfs-for-4.2-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (28 commits) nfs: Fix an oops caused by using other thread's stack space in ASYNC mode nfs: plug memory leak when ->prepare_layoutcommit fails SUNRPC: Report TCP errors to the caller sunrpc: translate -EAGAIN to -ENOBUFS when socket is writable. NFSv4.2: handle NFS-specific llseek errors NFS: Don't clear desc->pg_moreio in nfs_do_recoalesce() NFS: Fix a memory leak in nfs_do_recoalesce NFS: nfs_mark_for_revalidate should always set NFS_INO_REVAL_PAGECACHE NFS: Remove the "NFS_CAP_CHANGE_ATTR" capability NFS: Set NFS_INO_REVAL_PAGECACHE if the change attribute is uninitialised NFS: Don't revalidate the mapping if both size and change attr are up to date NFSv4/pnfs: Ensure we don't miss a file extension NFSv4: We must set NFS_OPEN_STATE flag in nfs_resync_open_stateid_locked SUNRPC: xprt_complete_bc_request must also decrement the free slot count SUNRPC: Fix a backchannel deadlock pNFS: Don't throw out valid layout segments pNFS: pnfs_roc_drain() fix a race with open pNFS: Fix races between return-on-close and layoutreturn. pNFS: pnfs_roc_drain should return 'true' when sleeping pNFS: Layoutreturn must invalidate all existing layout segments. ...
2015-07-27SUNRPC: Report TCP errors to the callerTrond Myklebust1-7/+6
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-27sunrpc: translate -EAGAIN to -ENOBUFS when socket is writable.NeilBrown1-0/+9
The networking layer does not reliably report the distinction between a non-block write failing because: 1/ the queue is too full already and 2/ a memory allocation attempt failed. The distinction is important because in the first case it is appropriate to retry as soon as the socket reports that it is writable, and in the second case a small delay is required as the socket will most likely report as writable but kmalloc could still fail. sk_stream_wait_memory() exhibits this distinction nicely, setting 'vm_wait' if a small wait is needed. However in the non-blocking case it always returns -EAGAIN no matter the cause of the failure. This -EAGAIN call get all the way to sunrpc. The sunrpc layer expects EAGAIN to indicate the first cause, and ENOBUFS to indicate the second. Various documentation suggests that this is not unreasonable, but does not guarantee the desired error codes. The result of getting -EAGAIN when -ENOBUFS is expected is that the send is tried again in a tight loop and soft lockups are reported. so: add tests after calls to xs_sendpages() to translate -EAGAIN into -ENOBUFS if the socket is writable. This cannot happen inside xs_sendpages() as the test for "is socket writable" is different between TCP and UDP. With this change, the tight loop retrying xs_sendpages() becomes a loop which only retries every 250ms, and so will not trigger a soft-lockup warning. It is possible that the write did fail because the queue was too full and by the time xs_sendpages() completed, the queue was writable again. In this case an extra 250ms delay is inserted that isn't really needed. This circumstance suggests a degree of congestion so a delay is not necessarily a bad thing, and it can only cause a single 250ms delay, not a series of them. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-03SUNRPC: Don't confuse ENOBUFS with a write_space issueTrond Myklebust1-1/+2
ENOBUFS means that memory allocations are failing due to an actual low memory situation. It should not be confused with being out of socket buffer space. Handle the problem by just punting to the delay in call_status. Reported-by: Neil Brown <neilb@suse.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-07-02Merge tag 'nfs-for-4.2-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds1-43/+108
Pull NFS client updates from Trond Myklebust: "Highlights include: Stable patches: - Fix a crash in the NFSv4 file locking code. - Fix an fsync() regression, where we were failing to retry I/O in some circumstances. - Fix an infinite loop in NFSv4.0 OPEN stateid recovery - Fix a memory leak when an attempted pnfs fails. - Fix a memory leak in the backchannel code - Large hostnames were not supported correctly in NFSv4.1 - Fix a pNFS/flexfiles bug that was impeding error reporting on I/O. - Fix a couple of credential issues in pNFS/flexfiles Bugfixes + cleanups: - Open flag sanity checks in the NFSv4 atomic open codepath - More NFSv4 delegation related bugfixes - Various NFSv4.1 backchannel bugfixes and cleanups - Fix the NFS swap socket code - Various cleanups of the NFSv4 SETCLIENTID and EXCHANGE_ID code - Fix a UDP transport deadlock issue Features: - More RDMA client transport improvements - NFSv4.2 LAYOUTSTATS functionality for pnfs flexfiles" * tag 'nfs-for-4.2-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (87 commits) nfs: Remove invalid tk_pid from debug message nfs: Remove invalid NFS_ATTR_FATTR_V4_REFERRAL checking in nfs4_get_rootfh nfs: Drop bad comment in nfs41_walk_client_list() nfs: Remove unneeded micro checking of CONFIG_PROC_FS nfs: Don't setting FILE_CREATED flags always nfs: Use remove_proc_subtree() instead remove_proc_entry() nfs: Remove unused argument in nfs_server_set_fsinfo() nfs: Fix a memory leak when meeting an unsupported state protect nfs: take extra reference to fl->fl_file when running a LOCKU operation NFSv4: When returning a delegation, don't reclaim an incompatible open mode. NFSv4.2: LAYOUTSTATS is optional to implement NFSv4.2: Fix up a decoding error in layoutstats pNFS/flexfiles: Fix the reset of struct pgio_header when resending pNFS/flexfiles: Turn off layoutcommit for servers that don't need it pnfs/flexfiles: protect ktime manipulation with mirror lock nfs: provide pnfs_report_layoutstat when NFS42 is disabled nfs: verify open flags before allowing open nfs: always update creds in mirror, even when we have an already connected ds nfs: fix potential credential leak in ff_layout_update_mirror_cred pnfs/flexfiles: report layoutstat regularly ...
2015-06-20SUNRPC: Set the TCP user timeout option on client socketsTrond Myklebust1-0/+7
Use the TCP_USER_TIMEOUT socket option to advertise to the server how long we will keep the connection open if there is unacknowledged data. See RFC5482. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-19SUNRPC: Ensure we release the TCP socket once it has been closedTrond Myklebust1-18/+22
This fixes a regression introduced by commit caf4ccd4e88cf2 ("SUNRPC: Make xs_tcp_close() do a socket shutdown rather than a sock_release"). Prior to that commit, the autoclose feature would ensure that an idle connection would result in the socket being both disconnected and released, whereas now only gets disconnected. While the current behaviour is harmless, it does leave the port bound until either RPC traffic resumes or the RPC client is shut down. Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10SUNRPC: Transport fault injectionChuck Lever1-0/+10
It has been exceptionally useful to exercise the logic that handles local immediate errors and RDMA connection loss. To enable developers to test this regularly and repeatably, add logic to simulate connection loss every so often. Fault injection is disabled by default. It is enabled with $ sudo echo xxx > /sys/kernel/debug/sunrpc/inject_fault/disconnect where "xxx" is a large positive number of transport method calls before a disconnect. A value of several thousand is usually a good number that allows reasonable forward progress while still causing a lot of connection drops. These hooks are disabled when SUNRPC_DEBUG is turned off. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10sunrpc: turn swapper_enable/disable functions into rpc_xprt_opsJeff Layton1-6/+25
RDMA xprts don't have a sock_xprt, but an rdma_xprt, so the xs_swapper_enable/disable functions will likely oops when fed an RDMA xprt. Turn these functions into rpc_xprt_ops so that that doesn't occur. For now the RDMA versions are no-ops that just return -EINVAL on an attempt to swapon. Cc: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Jeff Layton <jeff.layton@primarydata.com> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10sunrpc: lock xprt before trying to set memalloc on the socketsJeff Layton1-8/+27
It's possible that we could race with a call to xs_reset_transport, in which case the xprt->inet pointer could be zeroed out while we're accessing it. Lock the xprt before we try to set memalloc on it. Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Jeff Layton <jeff.layton@primarydata.com> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10sunrpc: if we're closing down a socket, clear memalloc on it firstJeff Layton1-0/+3
We currently increment the memalloc_socks counter if we have a xprt that is associated with a swapfile. That socket can be replaced however during a reconnect event, and the memalloc_socks counter is never decremented if that occurs. When tearing down a xprt socket, check to see if the xprt is set up for swapping and sk_clear_memalloc before releasing the socket if so. Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Jeff Layton <jeff.layton@primarydata.com> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10sunrpc: make xprt->swapper an atomic_tJeff Layton1-13/+25
Split xs_swapper into enable/disable functions and eliminate the "enable" flag. Currently, it's racy if you have multiple swapon/swapoff operations running in parallel over the same xprt. Also fix it so that we only set it to a memalloc socket on a 0->1 transition and only clear it on a 1->0 transition. Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Jeff Layton <jeff.layton@primarydata.com> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10sunrpc: keep a count of swapfiles associated with the rpc_clntJeff Layton1-2/+1
Jerome reported seeing a warning pop when working with a swapfile on NFS. The nfs_swap_activate can end up calling sk_set_memalloc while holding the rcu_read_lock and that function can sleep. To fix that, we need to take a reference to the xprt while holding the rcu_read_lock, set the socket up for swapping and then drop that reference. But, xprt_put is not exported and having NFS deal with the underlying xprt is a bit of layering violation anyway. Fix this by adding a set of activate/deactivate functions that take a rpc_clnt pointer instead of an rpc_xprt, and have nfs_swap_activate and nfs_swap_deactivate call those. Also, add a per-rpc_clnt atomic counter to keep track of the number of active swapfiles associated with it. When the counter does a 0->1 transition, we enable swapping on the xprt, when we do a 1->0 transition we disable swapping on it. This also allows us to be a bit more selective with the RPC_TASK_SWAPPER flag. If non-swapper and swapper clnts are sharing a xprt, then we only need to flag the tasks from the swapper clnt with that flag. Acked-by: Mel Gorman <mgorman@suse.de> Reported-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Jeff Layton <jeff.layton@primarydata.com> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-02SUNRPC: drop stale doc comments in xprtsock.cStefan Hajnoczi1-8/+0
Several functions have outdated arguments listed in the doc comments. Drop documentation for arguments that no longer exist. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-05-28kernel/params: constify struct kernel_param_ops usesLuis R. Rodriguez1-3/+3
Most code already uses consts for the struct kernel_param_ops, sweep the kernel for the last offending stragglers. Other than include/linux/moduleparam.h and kernel/params.c all other changes were generated with the following Coccinelle SmPL patch. Merge conflicts between trees can be handled with Coccinelle. In the future git could get Coccinelle merge support to deal with patch --> fail --> grammar --> Coccinelle --> new patch conflicts automatically for us on patches where the grammar is available and the patch is of high confidence. Consider this a feature request. Test compiled on x86_64 against: * allnoconfig * allmodconfig * allyesconfig @ const_found @ identifier ops; @@ const struct kernel_param_ops ops = { }; @ const_not_found depends on !const_found @ identifier ops; @@ -struct kernel_param_ops ops = { +const struct kernel_param_ops ops = { }; Generated-by: Coccinelle SmPL Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Junio C Hamano <gitster@pobox.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Kees Cook <keescook@chromium.org> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: cocci@systeme.lip6.fr Cc: linux-kernel@vger.kernel.org Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-02-10SUNRPC: Cleanup to remove xs_tcp_close()Trond Myklebust1-6/+1
xs_tcp_close() is now just a call to xs_tcp_shutdown(), so remove it, and replace the entry in xs_tcp_ops. Suggested-by: Anna Schumaker <anna.schumaker@netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09SUNRPC: Fix stupid typo in xs_sock_set_reuseportTrond Myklebust1-2/+3
Yes, kernel_setsockopt() hates you for using a char argument. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09SUNRPC: Define xs_tcp_fin_timeout only if CONFIG_SUNRPC_DEBUGTrond Myklebust1-2/+2
Now that the linger code is gone, the xs_tcp_fin_timeout variable has no real function. Keep it for now, since it is part of the /proc interface, but only define it if that /proc interface is enabled. Suggested-by: Anna Schumaker <Anna.Schumaker@netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09SUNRPC: Handle connection reset more efficiently.Trond Myklebust1-16/+18
If the connection reset is due to an active call on our side, then the state change is sometimes not reported. Catch those instances using xs_error_report() instead. Also remove the xs_tcp_shutdown() call in xs_tcp_send_request() as the change in behaviour makes it redundant. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09SUNRPC: Remove the redundant XPRT_CONNECTION_CLOSE flagTrond Myklebust1-1/+0
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09SUNRPC: Make xs_tcp_close() do a socket shutdown rather than a sock_releaseTrond Myklebust1-5/+1
Use of socket shutdown() means that we monitor the shutdown process through the xs_tcp_state_change() callback, so it is preferable to a full close in all cases unless we're destroying the transport. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09SUNRPC: Ensure xs_tcp_shutdown() requests a full close of the connectionTrond Myklebust1-2/+2
The previous behaviour left the connection half-open in order to try to scrape the last replies from the socket. Now that we have more reliable reconnection, change the behaviour to close down the socket faster. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09SUNRPC: Cleanup to remove remaining uses of XPRT_CONNECTION_ABORTTrond Myklebust1-3/+0
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-09SUNRPC: Remove TCP socket linger codeTrond Myklebust1-35/+0
Now that we no longer use the partial shutdown code when closing the socket, we no longer need to worry about the TCP linger2 state. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08SUNRPC: Remove TCP client connection reset hackTrond Myklebust1-66/+1
Instead we rely on SO_REUSEPORT to provide the reconnection semantics that we need for NFSv2/v3. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08SUNRPC: TCP/UDP always close the old socket before reconnectingTrond Myklebust1-2/+3
It is not safe to call xs_reset_transport() from inside xs_udp_setup_socket() or xs_tcp_setup_socket(), since they do not own the correct locks. Instead, do it in xs_connect(). Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08SUNRPC: Add helpers to prevent socket create from racingTrond Myklebust1-2/+5
The socket lock is currently held by the task that is requesting the connection be established. While that is efficient in the case where the connection happens quickly, it is racy in the case where it doesn't. What we really want is for the connect helper to be able to block access to the socket while it is being set up. This patch does so by arranging to transfer the socket lock from the task that is requesting the connect attempt, and then releasing that lock once everything is done. This scheme also gives us automatic protection against collisions with the RPC close code, so we can kill the cancel_delayed_work_sync() call in xs_close(). Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08SUNRPC: Ensure xs_reset_transport() resets the close connection flagsTrond Myklebust1-16/+13
Otherwise, we may end up looping. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08SUNRPC: Do not clear the source port in xs_reset_transportTrond Myklebust1-2/+0
Now that we can reuse bound ports after a close, we never really want to clear the transport's source port after it has been set. Doing so really messes up the NFSv3 DRC on the server. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08SUNRPC: Handle EADDRINUSE on connectTrond Myklebust1-0/+2
Now that we're setting SO_REUSEPORT, we still need to handle the case where a connect() is attempted, but the old socket is still lingering. Essentially, all we want to do here is handle the error by waiting a few seconds and then retrying. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-08SUNRPC: Set SO_REUSEPORT socket option for TCP connectionsTrond Myklebust1-4/+49
When using TCP, we need the ability to reuse port numbers after a disconnection, so that the NFSv3 server knows that we're the same client. Currently we use a hack to work around the TCP socket's TIME_WAIT: we send an RST instead of closing, which doesn't always work... The SO_REUSEPORT option added in Linux 3.9 allows us to bind multiple TCP connections to the same source address+port combination, and thus to use ordinary TCP close() instead of the current hack. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-24sunrpc: eliminate RPC_DEBUGJeff Layton1-4/+4
It's always set to whatever CONFIG_SUNRPC_DEBUG is, so just use that. Signed-off-by: Jeff Layton <jlayton@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-24sunrpc: add tracepoints in xs_tcp_data_recvJeff Layton1-59/+2
Add tracepoints inside the main loop on xs_tcp_data_recv that allow us to keep an eye on what's happening during each phase of it. Signed-off-by: Jeff Layton <jlayton@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-24sunrpc: add new tracepoints in xprt handling codeJeff Layton1-1/+7
...so we can keep track of when calls are sent and replies received. Signed-off-by: Jeff Layton <jlayton@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-25NFS/SUNRPC: Remove other deadlock-avoidance mechanisms in nfs_release_page()NeilBrown1-10/+0
Now that nfs_release_page() doesn't block indefinitely, other deadlock avoidance mechanisms aren't needed. - it doesn't hurt for kswapd to block occasionally. If it doesn't want to block it would clear __GFP_WAIT. The current_is_kswapd() was only added to avoid deadlocks and we have a new approach for that. - memory allocation in the SUNRPC layer can very rarely try to ->releasepage() a page it is trying to handle. The deadlock is removed as nfs_release_page() doesn't block indefinitely. So we don't need to set PF_FSTRANS for sunrpc network operations any more. Signed-off-by: NeilBrown <neilb@suse.de> Acked-by: Jeff Layton <jlayton@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-24rpc: Add -EPERM processing for xs_udp_send_request()Jason Baron1-0/+6
If an iptables drop rule is added for an nfs server, the client can end up in a softlockup. Because of the way that xs_sendpages() is structured, the -EPERM is ignored since the prior bits of the packet may have been successfully queued and thus xs_sendpages() returns a non-zero value. Then, xs_udp_send_request() thinks that because some bits were queued it should return -EAGAIN. We then try the request again and again, resulting in cpu spinning. Reproducer: 1) open a file on the nfs server '/nfs/foo' (mounted using udp) 2) iptables -A OUTPUT -d <nfs server ip> -j DROP 3) write to /nfs/foo 4) close /nfs/foo 5) iptables -D OUTPUT -d <nfs server ip> -j DROP The softlockup occurs in step 4 above. The previous patch, allows xs_sendpages() to return both a sent count and any error values that may have occurred. Thus, if we get an -EPERM, return that to the higher level code. With this patch in place we can successfully abort the above sequence and avoid the softlockup. I also tried the above test case on an nfs mount on tcp and although the system does not softlockup, I still ended up with the 'hung_task' firing after 120 seconds, due to the i/o being stuck. The tcp case appears a bit harder to fix, since -EPERM appears to get ignored much lower down in the stack and does not propogate up to xs_sendpages(). This case is not quite as insidious as the softlockup and it is not addressed here. Reported-by: Yigong Lou <ylou@akamai.com> Signed-off-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-24rpc: return sent and err from xs_sendpages()Jason Baron1-39/+42
If an error is returned after the first bits of a packet have already been successfully queued, xs_sendpages() will return a positive 'int' value indicating success. Callers seem to treat this as -EAGAIN. However, there are cases where its not a question of waiting for the write queue to drain. For example, when there is an iptables rule dropping packets to the destination, the lower level code can return -EPERM only after parts of the packet have been successfully queued. In this case, we can end up continuously retrying resulting in a kernel softlockup. This patch is intended to make no changes in behavior but is in preparation for subsequent patches that can make decisions based on both on the number of bytes sent by xs_sendpages() and any errors that may have be returned. Signed-off-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-24SUNRPC: Don't wake tasks during connection abortBenjamin Coddington1-0/+4
When aborting a connection to preserve source ports, don't wake the task in xs_error_report. This allows tasks with RPC_TASK_SOFTCONN to succeed if the connection needs to be re-established since it preserves the task's status instead of setting it to the status of the aborting kernel_connect(). This may also avoid a potential conflict on the socket's lock. Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Cc: stable@vger.kernel.org # 3.14+ Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-10rpc: xs_bind - do not bind when requesting a random ephemeral portChris Perl1-2/+18
When attempting to establish a local ephemeral endpoint for a TCP or UDP socket, do not explicitly call bind, instead let it happen implicilty when the socket is first used. The main motivating factor for this change is when TCP runs out of unique ephemeral ports (i.e. cannot find any ephemeral ports which are not a part of *any* TCP connection). In this situation if you explicitly call bind, then the call will fail with EADDRINUSE. However, if you allow the allocation of an ephemeral port to happen implicitly as part of connect (or other functions), then ephemeral ports can be reused, so long as the combination of (local_ip, local_port, remote_ip, remote_port) is unique for TCP sockets on the system. This doesn't matter for UDP sockets, but it seemed easiest to treat TCP and UDP sockets the same. This can allow mount.nfs(8) to continue to function successfully, even in the face of misbehaving applications which are creating a large number of TCP connections. Signed-off-by: Chris Perl <chris.perl@gmail.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-07-12replace strict_strto callsDaniel Walter1-2/+2
Replace obsolete strict_strto calls with appropriate kstrto calls Signed-off-by: Daniel Walter <dwalter@google.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-06-30SUNRPC: Ensure that we handle ENOBUFS errors correctly.Trond Myklebust1-0/+5
Currently, an ENOBUFS error will result in a fatal error for the RPC call. Normally, we will just want to wait and then retry. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-06-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds1-3/+0
Pull networking updates from David Miller: 1) Seccomp BPF filters can now be JIT'd, from Alexei Starovoitov. 2) Multiqueue support in xen-netback and xen-netfront, from Andrew J Benniston. 3) Allow tweaking of aggregation settings in cdc_ncm driver, from Bjørn Mork. 4) BPF now has a "random" opcode, from Chema Gonzalez. 5) Add more BPF documentation and improve test framework, from Daniel Borkmann. 6) Support TCP fastopen over ipv6, from Daniel Lee. 7) Add software TSO helper functions and use them to support software TSO in mvneta and mv643xx_eth drivers. From Ezequiel Garcia. 8) Support software TSO in fec driver too, from Nimrod Andy. 9) Add Broadcom SYSTEMPORT driver, from Florian Fainelli. 10) Handle broadcasts more gracefully over macvlan when there are large numbers of interfaces configured, from Herbert Xu. 11) Allow more control over fwmark used for non-socket based responses, from Lorenzo Colitti. 12) Do TCP congestion window limiting based upon measurements, from Neal Cardwell. 13) Support busy polling in SCTP, from Neal Horman. 14) Allow RSS key to be configured via ethtool, from Venkata Duvvuru. 15) Bridge promisc mode handling improvements from Vlad Yasevich. 16) Don't use inetpeer entries to implement ID generation any more, it performs poorly, from Eric Dumazet. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1522 commits) rtnetlink: fix userspace API breakage for iproute2 < v3.9.0 tcp: fixing TLP's FIN recovery net: fec: Add software TSO support net: fec: Add Scatter/gather support net: fec: Increase buffer descriptor entry number net: fec: Factorize feature setting net: fec: Enable IP header hardware checksum net: fec: Factorize the .xmit transmit function bridge: fix compile error when compiling without IPv6 support bridge: fix smatch warning / potential null pointer dereference via-rhine: fix full-duplex with autoneg disable bnx2x: Enlarge the dorq threshold for VFs bnx2x: Check for UNDI in uncommon branch bnx2x: Fix 1G-baseT link bnx2x: Fix link for KR with swapped polarity lane sctp: Fix sk_ack_backlog wrap-around problem net/core: Add VF link state control policy net/fsl: xgmac_mdio is dependent on OF_MDIO net/fsl: Make xgmac_mdio read error message useful net_sched: drr: warn when qdisc is not work conserving ...
2014-05-23sunrpc: Remove sk_no_check settingTom Herbert1-3/+0
Setting sk_no_check to UDP_CSUM_NORCV seems to have no effect. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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