commit 06ea0bfe6e6043cb56a78935a19f6f8ebc636226 upstream.
When a send failure occurs due to the socket being out of buffer space,
we call xs_nospace() in order to have the RPC task wait until the
socket has drained enough to make it worth while trying again.
The current patch fixes a race in which the socket is drained before
we get round to setting up the machinery in xs_nospace(), and which
is reported to cause hangs.
Link: http://lkml.kernel.org/r/20140210170315.33dfc621@notabene.brown
Fixes: a9a6b52ee1 (SUNRPC: Don't start the retransmission timer...)
Reported-by: Neil Brown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a6b31d18b02ff9d7915c5898c9b5ca41a798cd73 upstream.
The following scenario can cause silent data corruption when doing
NFS writes. It has mainly been observed when doing database writes
using O_DIRECT.
1) The RPC client uses sendpage() to do zero-copy of the page data.
2) Due to networking issues, the reply from the server is delayed,
and so the RPC client times out.
3) The client issues a second sendpage of the page data as part of
an RPC call retransmission.
4) The reply to the first transmission arrives from the server
_before_ the client hardware has emptied the TCP socket send
buffer.
5) After processing the reply, the RPC state machine rules that
the call to be done, and triggers the completion callbacks.
6) The application notices the RPC call is done, and reuses the
pages to store something else (e.g. a new write).
7) The client NIC drains the TCP socket send buffer. Since the
page data has now changed, it reads a corrupted version of the
initial RPC call, and puts it on the wire.
This patch fixes the problem in the following manner:
The ordering guarantees of TCP ensure that when the server sends a
reply, then we know that the _first_ transmission has completed. Using
zero-copy in that situation is therefore safe.
If a time out occurs, we then send the retransmission using sendmsg()
(i.e. no zero-copy), We then know that the socket contains a full copy of
the data, and so it will retransmit a faithful reproduction even if the
RPC call completes, and the application reuses the O_DIRECT buffer in
the meantime.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the gss-proxy case, setup time is when I know I'll have the right
namespace for the connect.
In other cases, it might be useful to get any connection errors
earlier--though actually in practice it doesn't make any difference for
rpcbind.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Merging Trond's nfs-for-next branch, mainly to get
b7993cebb8 "SUNRPC: Allow rpc_create() to
request that TCP slots be unlimited", which a small piece of the
gss-proxy work depends on.
This is mainly for use by NFSv4.1, where the session negotiation
ultimately wants to decide how many RPC slots we can fill.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In the case of a SOFTCONN rpc task, we really want to ensure that it
reports errors like ENETUNREACH back to the caller. Currently, only
some of these errors are being reported back (connect errors are not),
and they are being converted by the RPC layer into EIO.
Reported-by: Jan Engelhardt <jengelh@inai.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Pull nfsd changes from J Bruce Fields:
"Miscellaneous bugfixes, plus:
- An overhaul of the DRC cache by Jeff Layton. The main effect is
just to make it larger. This decreases the chances of intermittent
errors especially in the UDP case. But we'll need to watch for any
reports of performance regressions.
- Containerized nfsd: with some limitations, we now support
per-container nfs-service, thanks to extensive work from Stanislav
Kinsbursky over the last year."
Some notes about conflicts, since there were *two* non-data semantic
conflicts here:
- idr_remove_all() had been added by a memory leak fix, but has since
become deprecated since idr_destroy() does it for us now.
- xs_local_connect() had been added by this branch to make AF_LOCAL
connections be synchronous, but in the meantime Trond had changed the
calling convention in order to avoid a RCU dereference.
There were a couple of more obvious actual source-level conflicts due to
the hlist traversal changes and one just due to code changes next to
each other, but those were trivial.
* 'for-3.9' of git://linux-nfs.org/~bfields/linux: (49 commits)
SUNRPC: make AF_LOCAL connect synchronous
nfsd: fix compiler warning about ambiguous types in nfsd_cache_csum
svcrpc: fix rpc server shutdown races
svcrpc: make svc_age_temp_xprts enqueue under sv_lock
lockd: nlmclnt_reclaim(): avoid stack overflow
nfsd: enable NFSv4 state in containers
nfsd: disable usermode helper client tracker in container
nfsd: use proper net while reading "exports" file
nfsd: containerize NFSd filesystem
nfsd: fix comments on nfsd_cache_lookup
SUNRPC: move cache_detail->cache_request callback call to cache_read()
SUNRPC: remove "cache_request" argument in sunrpc_cache_pipe_upcall() function
SUNRPC: rework cache upcall logic
SUNRPC: introduce cache_detail->cache_request callback
NFS: simplify and clean cache library
NFS: use SUNRPC cache creation and destruction helper for DNS cache
nfsd4: free_stid can be static
nfsd: keep a checksum of the first 256 bytes of request
sunrpc: trim off trailing checksum before returning decrypted or integrity authenticated buffer
sunrpc: fix comment in struct xdr_buf definition
...
It doesn't appear that anyone actually needs to connect asynchronously.
Also, using a workqueue for the connect means we lose the namespace
information from the original process. This is a problem since there's
no way to explicitly pass in a filesystem namespace for resolution of an
AF_LOCAL address.
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
These routines are used by server and client code, so having them in a
separate header would be best.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
tk_xprt is just a shortcut for tk_client->cl_xprt, however cl_xprt is
defined as an __rcu variable. Replace dereferences of tk_xprt with
non-rcu dereferences where it is safe to do so.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Silence the unnecessary warning "unhandled error (111) connecting to..."
and convert it to a dprintk for debugging purposes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Replace BUG_ON() with WARN_ON_ONCE() and NULL return - the caller will handle
this like a memory allocation failure.
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Replace multiple BUG_ON() calls with WARN_ON_ONCE() and early return when
sanity checking socket ownership (lock). The bind call will fail if the
socket was unsuccessfully reclassified.
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Chris Perl reports that we're seeing races between the wakeup call in
xs_error_report and the connect attempts. Basically, Chris has shown
that in certain circumstances, the call to xs_error_report causes the
rpc_task that is responsible for reconnecting to wake up early, thus
triggering a disconnect and retry.
Since the sk->sk_error_report() calls in the socket layer are always
followed by a tcp_done() in the cases where we care about waking up
the rpc_tasks, just let the state_change callbacks take responsibility
for those wake ups.
Reported-by: Chris Perl <chris.perl@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
Tested-by: Chris Perl <chris.perl@gmail.com>
The call to xprt_disconnect_done() that is triggered by a successful
connection reset will trigger another automatic wakeup of all tasks
on the xprt->pending rpc_wait_queue. In particular it will cause an
early wake up of the task that called xprt_connect().
All we really want to do here is clear all the socket-specific state
flags, so we split that functionality out of xs_sock_mark_closed()
into a helper that can be called by xs_abort_connection()
Reported-by: Chris Perl <chris.perl@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
Tested-by: Chris Perl <chris.perl@gmail.com>
This reverts commit 55420c24a0.
Now that we clear the connected flag when entering TCP_CLOSE_WAIT,
the deadlock described in this commit is no longer possible.
Instead, the resulting call to xs_tcp_shutdown() can interfere
with pending reconnection attempts.
Reported-by: Chris Perl <chris.perl@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
Tested-by: Chris Perl <chris.perl@gmail.com>
This is needed to ensure that we call xprt_connect() upon the next
call to call_connect().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
Tested-by: Chris Perl <chris.perl@gmail.com>
It is only set after everyone has dereferenced the transport,
and serves no useful purpose: setting it is racy, so all the
socket code, etc still needs to be able to cope with the cases
where they miss reading it.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Instead of doing a shutdown() call, we need to do an actual close().
Ditto if/when the server is sending us junk RPC headers.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Simon Kirby <sim@hostway.ca>
Cc: stable@vger.kernel.org
Commit 43cedbf0e8 (SUNRPC: Ensure that
we grab the XPRT_LOCK before calling xprt_alloc_slot) is causing
hangs in the case of NFS over UDP mounts.
Since neither the UDP or the RDMA transport mechanism use dynamic slot
allocation, we can skip grabbing the socket lock for those transports.
Add a new rpc_xprt_op to allow switching between the TCP and UDP/RDMA
case.
Note that the NFSv4.1 back channel assigns the slot directly
through rpc_run_bc_task, so we can ignore that case.
Reported-by: Dick Streefland <dick.streefland@altium.nl>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org [>= 3.1]
Merge Andrew's second set of patches:
- MM
- a few random fixes
- a couple of RTC leftovers
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (120 commits)
rtc/rtc-88pm80x: remove unneed devm_kfree
rtc/rtc-88pm80x: assign ret only when rtc_register_driver fails
mm: hugetlbfs: close race during teardown of hugetlbfs shared page tables
tmpfs: distribute interleave better across nodes
mm: remove redundant initialization
mm: warn if pg_data_t isn't initialized with zero
mips: zero out pg_data_t when it's allocated
memcg: gix memory accounting scalability in shrink_page_list
mm/sparse: remove index_init_lock
mm/sparse: more checks on mem_section number
mm/sparse: optimize sparse_index_alloc
memcg: add mem_cgroup_from_css() helper
memcg: further prevent OOM with too many dirty pages
memcg: prevent OOM with too many dirty pages
mm: mmu_notifier: fix freed page still mapped in secondary MMU
mm: memcg: only check anon swapin page charges for swap cache
mm: memcg: only check swap cache pages for repeated charging
mm: memcg: split swapin charge function into private and public part
mm: memcg: remove needless !mm fixup to init_mm when charging
mm: memcg: remove unneeded shmem charge type
...
Features include:
- Patches from Bryan to allow splitting of the NFSv2/v3/v4 code into
separate modules.
- Fix Oopses in the NFSv4 idmapper
- Fix a deadlock whereby rpciod tries to allocate a new socket and
ends up recursing into the NFS code due to memory reclaim.
- Increase the number of permitted callback connections.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)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=KSix
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-3.6-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull second wave of NFS client updates from Trond Myklebust:
- Patches from Bryan to allow splitting of the NFSv2/v3/v4 code into
separate modules.
- Fix Oopses in the NFSv4 idmapper
- Fix a deadlock whereby rpciod tries to allocate a new socket and ends
up recursing into the NFS code due to memory reclaim.
- Increase the number of permitted callback connections.
* tag 'nfs-for-3.6-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
nfs: explicitly reject LOCK_MAND flock() requests
nfs: increase number of permitted callback connections.
SUNRPC: return negative value in case rpcbind client creation error
NFS: Convert v4 into a module
NFS: Convert v3 into a module
NFS: Convert v2 into a module
NFS: Keep module parameters in the generic NFS client
NFS: Split out remaining NFS v4 inode functions
NFS: Pass super operations and xattr handlers in the nfs_subversion
NFS: Only initialize the ACL client in the v3 case
NFS: Create a try_mount rpc op
NFS: Remove the NFS v4 xdev mount function
NFS: Add version registering framework
NFS: Fix a number of bugs in the idmapper
nfs: skip commit in releasepage if we're freeing memory for fs-related reasons
sunrpc: clarify comments on rpc_make_runnable
pnfsblock: bail out partial page IO
Implement the new swapfile a_ops for NFS and hook up ->direct_IO. This
will set the NFS socket to SOCK_MEMALLOC and run socket reconnect under
PF_MEMALLOC as well as reset SOCK_MEMALLOC before engaging the protocol
->connect() method.
PF_MEMALLOC should allow the allocation of struct socket and related
objects and the early (re)setting of SOCK_MEMALLOC should allow us to
receive the packets required for the TCP connection buildup.
[jlayton@redhat.com: Restore PF_MEMALLOC task flags in all cases]
[dfeng@redhat.com: Fix handling of multiple swap files]
[a.p.zijlstra@chello.nl: Original patch]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Eric Paris <eparis@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: Neil Brown <neilb@suse.de>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Xiaotian Feng <dfeng@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We've had some reports of a deadlock where rpciod ends up with a stack
trace like this:
PID: 2507 TASK: ffff88103691ab40 CPU: 14 COMMAND: "rpciod/14"
#0 [ffff8810343bf2f0] schedule at ffffffff814dabd9
#1 [ffff8810343bf3b8] nfs_wait_bit_killable at ffffffffa038fc04 [nfs]
#2 [ffff8810343bf3c8] __wait_on_bit at ffffffff814dbc2f
#3 [ffff8810343bf418] out_of_line_wait_on_bit at ffffffff814dbcd8
#4 [ffff8810343bf488] nfs_commit_inode at ffffffffa039e0c1 [nfs]
#5 [ffff8810343bf4f8] nfs_release_page at ffffffffa038bef6 [nfs]
#6 [ffff8810343bf528] try_to_release_page at ffffffff8110c670
#7 [ffff8810343bf538] shrink_page_list.clone.0 at ffffffff81126271
#8 [ffff8810343bf668] shrink_inactive_list at ffffffff81126638
#9 [ffff8810343bf818] shrink_zone at ffffffff8112788f
#10 [ffff8810343bf8c8] do_try_to_free_pages at ffffffff81127b1e
#11 [ffff8810343bf958] try_to_free_pages at ffffffff8112812f
#12 [ffff8810343bfa08] __alloc_pages_nodemask at ffffffff8111fdad
#13 [ffff8810343bfb28] kmem_getpages at ffffffff81159942
#14 [ffff8810343bfb58] fallback_alloc at ffffffff8115a55a
#15 [ffff8810343bfbd8] ____cache_alloc_node at ffffffff8115a2d9
#16 [ffff8810343bfc38] kmem_cache_alloc at ffffffff8115b09b
#17 [ffff8810343bfc78] sk_prot_alloc at ffffffff81411808
#18 [ffff8810343bfcb8] sk_alloc at ffffffff8141197c
#19 [ffff8810343bfce8] inet_create at ffffffff81483ba6
#20 [ffff8810343bfd38] __sock_create at ffffffff8140b4a7
#21 [ffff8810343bfd98] xs_create_sock at ffffffffa01f649b [sunrpc]
#22 [ffff8810343bfdd8] xs_tcp_setup_socket at ffffffffa01f6965 [sunrpc]
#23 [ffff8810343bfe38] worker_thread at ffffffff810887d0
#24 [ffff8810343bfee8] kthread at ffffffff8108dd96
#25 [ffff8810343bff48] kernel_thread at ffffffff8100c1ca
rpciod is trying to allocate memory for a new socket to talk to the
server. The VM ends up calling ->releasepage to get more memory, and it
tries to do a blocking commit. That commit can't succeed however without
a connected socket, so we deadlock.
Fix this by setting PF_FSTRANS on the workqueue task prior to doing the
socket allocation, and having nfs_release_page check for that flag when
deciding whether to do a commit call. Also, set PF_FSTRANS
unconditionally in rpc_async_schedule since that function can also do
allocations sometimes.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
xs_udp_data_ready() is operating on received packets, and tries to
do a dst_confirm() on the dst attached to the SKB.
This isn't right, dst confirmation is for output routes, not input
rights. It's for resetting the timers on the nexthop neighbour entry
for the route, indicating that we've got good evidence that we've
successfully reached it.
Signed-off-by: David S. Miller <davem@davemloft.net>
net/sunrpc/svcsock.c:412:22: warning: incorrect type in assignment
(different address spaces)
- svc_partial_recvfrom now takes a struct kvec, so the variable
save_iovbase needs to be an ordinary (void *)
Make a bunch of variables in net/sunrpc/xprtsock.c static
Fix a couple of "warning: symbol 'foo' was not declared. Should it be
static?" reports.
Fix a couple of conflicting function declarations.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
With static RPC slots, the xprt backlog queue stats were useful in showing
when the transport (TCP) was starved by lack of RPC slots. The new dynamic
RPC slot code, commit d9ba131d8f, always
provides an RPC slot and so only uses the xprt backlog queue when the
tcp_max_slot_table_entries value has been hit or when an allocation error
occurs. All requests are now placed on the xprt sending or pending queue which
need to be monitored for debugging.
The max_slot stat shows the maximum number of dynamic RPC slots reached which is
useful when debugging performance issues.
Add the new fields at the end of the mountstats xprt stanza so that mountstats
outputs the previous correct values and ignores the new fields. Bump
NFS_IOSTATS_VERS.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
By returning '0' instead of 'EAGAIN' when the tests in xs_nospace() fail
to find evidence of socket congestion, we are making the RPC engine believe
that the message was incorrectly sent and so it disconnects the socket
instead of just retrying.
The bug appears to have been introduced by commit
5e3771ce2d (SUNRPC: Ensure that xs_nospace
return values are propagated).
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org [>= 2.6.30]
Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Otherwise we will leak xprt structure and struct net reference.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This throttles the allocation of new slots when the socket is busy
reconnecting and/or is out of buffer space.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Change explicit references to CONFIG_NFS_V4_1 to implicit ones
Get rid of the unnecessary defines in backchannel_rqst.c and
bc_svc.c: the Makefile takes care of those dependency.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
TI-RPC introduces the capability of performing RPC over AF_LOCAL
sockets. It uses this mainly for registering and unregistering
local RPC services securely with the local rpcbind, but we could
also conceivably use it as a generic upcall mechanism.
This patch provides a client-side only implementation for the moment.
We might also consider a server-side implementation to provide
AF_LOCAL access to NLM (for statd downcalls, and such like).
Autobinding is not supported on kernel AF_LOCAL transports at this
time. Kernel ULPs must specify the pathname of the remote endpoint
when an AF_LOCAL transport is created. rpcbind supports registering
services available via AF_LOCAL, so the kernel could handle it with
some adjustment to ->rpcbind and ->set_port. But we don't need this
feature for doing upcalls via well-known named sockets.
This has not been tested with ULPs that move a substantial amount of
data. Thus, I can't attest to how robust the write_space and
congestion management logic is.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: Use a more generic name for xs_encode_tcp_fragment_header();
it's appropriate to use for all stream transport types. We're about
to add new stream transport.
Also, move it to a place where it is more easily shared amongst the
various send_request methods. And finally, replace the "htonl" macro
invocation with its modern equivalent.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The TCP connection state code depends on the state_change() callback
being called when the SYN_SENT state is set. However the networking layer
doesn't actually call us back in that case.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
If we call xs_close(), we're in one of two situations:
- Autoclose, which means we don't expect to resend a request
- bind+connect failed, which probably means the port is in use
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
xs_create_sock() is supposed to return a pointer or an ERR_PTR-encoded
error, but it currently returns 0 if xs_bind() fails.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Cc: stable@kernel.org [v2.6.37]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* 'for-2.6.38' of git://linux-nfs.org/~bfields/linux: (62 commits)
nfsd4: fix callback restarting
nfsd: break lease on unlink, link, and rename
nfsd4: break lease on nfsd setattr
nfsd: don't support msnfs export option
nfsd4: initialize cb_per_client
nfsd4: allow restarting callbacks
nfsd4: simplify nfsd4_cb_prepare
nfsd4: give out delegations more quickly in 4.1 case
nfsd4: add helper function to run callbacks
nfsd4: make sure sequence flags are set after destroy_session
nfsd4: re-probe callback on connection loss
nfsd4: set sequence flag when backchannel is down
nfsd4: keep finer-grained callback status
rpc: allow xprt_class->setup to return a preexisting xprt
rpc: keep backchannel xprt as long as server connection
rpc: move sk_bc_xprt to svc_xprt
nfsd4: allow backchannel recovery
nfsd4: support BIND_CONN_TO_SESSION
nfsd4: modify session list under cl_lock
Documentation: fl_mylease no longer exists
...
Fix up conflicts in fs/nfsd/vfs.c with the vfs-scale work. The
vfs-scale work touched some msnfs cases, and this merge removes support
for that entirely, so the conflict was trivial to resolve.
This allows us to reuse the xprt associated with a server connection if
one has already been set up.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Multiple backchannels can share the same tcp connection; from rfc 5661 section
2.10.3.1:
A connection's association with a session is not exclusive. A
connection associated with the channel(s) of one session may be
simultaneously associated with the channel(s) of other sessions
including sessions associated with other client IDs.
However, multiple backchannels share a connection, they must all share
the same xid stream (hence the same rpc_xprt); the only way we have to
match replies with calls at the rpc layer is using the xid.
So, keep the rpc_xprt around as long as the connection lasts, in case
we're asked to use the connection as a backchannel again.
Requests to create new backchannel clients over a given server
connection should results in creating new clients that reuse the
existing rpc_xprt.
But to start, just reject attempts to associate multiple rpc_xprt's with
the same underlying bc_xprt.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This seems obviously transport-level information even if it's currently
used only by the server socket code.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Peter Zijlstra
Trond Myklebust
Trond Myklebust
J. Bruce Fields
Linus Torvalds
Jeff Layton
Weston Andros Adamson
Bryan Schumaker
Mel Gorman
David S. Miller
Andy Adamson
Stanislav Kinsbursky
Chuck Lever
Lucas De Marchi
Ben Hutchings