linux.git/net/sunrpc, branch v4.20

SUNRPC: Remove xprt_connect_status()

2018-12-18T16:04:10+00:00

Over the years, xprt_connect_status() has been superseded by
call_connect_status(), which now handles all the errors that
xprt_connect_status() does and more. Since the latter converts
all errors that it doesn't recognise to EIO, then it is time
for it to be retired.

Reported-by: Chuck Lever 
Signed-off-by: Trond Myklebust 
Tested-by: Chuck Lever

SUNRPC: Fix a race with XPRT_CONNECTING

2018-12-18T16:04:03+00:00

Ensure that we clear XPRT_CONNECTING before releasing the XPRT_LOCK so that
we don't have races between the (asynchronous) socket setup code and
tasks in xprt_connect().

Signed-off-by: Trond Myklebust 
Tested-by: Chuck Lever

SUNRPC: Fix disconnection races

2018-12-18T16:03:57+00:00

When the socket is closed, we need to call xprt_disconnect_done() in order
to clean up the XPRT_WRITE_SPACE flag, and wake up the sleeping tasks.

However, we also want to ensure that we don't wake them up before the socket
is closed, since that would cause thundering herd issues with everyone
piling up to retransmit before the TCP shutdown dance has completed.
Only the task that holds XPRT_LOCKED needs to wake up early in order to
allow the close to complete.

Reported-by: Dave Wysochanski 
Reported-by: Scott Mayhew 
Cc: Chuck Lever 
Signed-off-by: Trond Myklebust 
Tested-by: Chuck Lever

SUNRPC: Don't force a redundant disconnection in xs_read_stream()

2018-12-05T12:11:12+00:00

If the connection is broken, then xs_tcp_state_change() will take care
of scheduling the socket close as soon as appropriate. xs_read_stream()
just needs to report the error.

Signed-off-by: Trond Myklebust

SUNRPC: Fix up socket polling

2018-12-05T12:11:12+00:00

Ensure that we do not exit the socket read callback without clearing
XPRT_SOCK_DATA_READY.

Signed-off-by: Trond Myklebust

SUNRPC: Use the discard iterator rather than MSG_TRUNC

2018-12-05T12:11:12+00:00

When discarding message data from the stream, we're better off using
the discard iterator, since that will work with non-TCP streams.

Signed-off-by: Trond Myklebust

SUNRPC: Treat EFAULT as a truncated message in xs_read_stream_request()

2018-12-05T12:11:12+00:00

Signed-off-by: Trond Myklebust

SUNRPC: Fix up handling of the XDRBUF_SPARSE_PAGES flag

2018-12-05T12:11:12+00:00

If the allocator fails before it has reached the target number of pages,
then we need to recheck that we're not seeking past the page buffer.

Signed-off-by: Trond Myklebust

SUNRPC: Fix RPC receive hangs

2018-12-05T12:10:06+00:00

The RPC code is occasionally hanging when the receive code fails to
empty the socket buffer due to a partial read of the data. When we
convert that to an EAGAIN, it appears we occasionally leave data in the
socket. The fix is to just keep reading until the socket returns
EAGAIN/EWOULDBLOCK.

Reported-by: Catalin Marinas 
Reported-by: Cristian Marussi 
Reported-by: Chuck Lever 
Signed-off-by: Trond Myklebust 
Tested-by: Catalin Marinas 
Tested-by: Cristian Marussi

SUNRPC: Fix a potential race in xprt_connect()

2018-12-02T14:43:57+00:00

If an asynchronous connection attempt completes while another task is
in xprt_connect(), then the call to rpc_sleep_on() could end up
racing with the call to xprt_wake_pending_tasks().
So add a second test of the connection state after we've put the
task to sleep and set the XPRT_CONNECTING flag, when we know that there
can be no asynchronous connection attempts still in progress.

Fixes: 0b9e79431377d ("SUNRPC: Move the test for XPRT_CONNECTING into...")
Signed-off-by: Trond Myklebust