user/sven/linux.git/include/linux/sunrpc/xprt.h, branch v4.9.296

SUNRPC: xprt_load_transport() needs to support the netid "rdma6"

2020-12-29T12:44:57Z

[ Upstream commit d5aa6b22e2258f05317313ecc02efbb988ed6d38 ] According to RFC5666, the correct netid for an IPv6 addressed RDMA transport is "rdma6", which we've supported as a mount option since Linux-4.7. The problem is when we try to load the module "xprtrdma6", that will fail, since there is no modulealias of that name. Fixes: 181342c5ebe8 ("xprtrdma: Add rdma6 option to support NFS/RDMA IPv6") Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin

SUNRPC: Add a transport-specific private field in rpc_rqst

2016-09-19T17:08:37Z

Currently there's a hidden and indirect mechanism for finding the rpcrdma_req that goes with an rpc_rqst. It depends on getting from the rq_buffer pointer in struct rpc_rqst to the struct rpcrdma_regbuf that controls that buffer, and then to the struct rpcrdma_req it goes with. This was done back in the day to avoid the need to add a per-rqst pointer or to alter the buf_free API when support for RPC-over-RDMA was introduced. I'm about to change the way regbuf's work to support larger inline thresholds. Now is a good time to replace this indirect mechanism with something that is more straightforward. I guess this should be considered a clean up. Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker

SUNRPC: Separate buffer pointers for RPC Call and Reply messages

2016-09-19T17:08:37Z

For xprtrdma, the RPC Call and Reply buffers are involved in real I/O operations. To start with, the DMA direction of the I/O for a Call is opposite that of a Reply. In the current arrangement, the Reply buffer address is on a four-byte alignment just past the call buffer. Would be friendlier on some platforms if that was at a DMA cache alignment instead. Because the current arrangement allocates a single memory region which contains both buffers, the RPC Reply buffer often contains a page boundary in it when the Call buffer is large enough (which is frequent). It would be a little nicer for setting up DMA operations (and possible registration of the Reply buffer) if the two buffers were separated, well-aligned, and contained as few page boundaries as possible. Now, I could just pad out the single memory region used for the pair of buffers. But frequently that would mean a lot of unused space to ensure the Reply buffer did not have a page boundary. Add a separate pointer to rpc_rqst that points right to the RPC Reply buffer. This makes no difference to xprtsock, but it will help xprtrdma in subsequent patches. Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker

SUNRPC: Generalize the RPC buffer release API

2016-09-19T17:08:37Z

xprtrdma needs to allocate the Call and Reply buffers separately. TBH, the reliance on using a single buffer for the pair of XDR buffers is transport implementation-specific. Instead of passing just the rq_buffer into the buf_free method, pass the task structure and let buf_free take care of freeing both XDR buffers at once. There's a micro-optimization here. In the common case, both xprt_release and the transport's buf_free method were checking if rq_buffer was NULL. Now the check is done only once per RPC. Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker

SUNRPC: Generalize the RPC buffer allocation API

2016-09-19T17:08:37Z

xprtrdma needs to allocate the Call and Reply buffers separately. TBH, the reliance on using a single buffer for the pair of XDR buffers is transport implementation-specific. Transports that want to allocate separate Call and Reply buffers will ignore the "size" argument anyway. Don't bother passing it. The buf_alloc method can't return two pointers. Instead, make the method's return value an error code, and set the rq_buffer pointer in the method itself. This gives call_allocate an opportunity to terminate an RPC instead of looping forever when a permanent problem occurs. If a request is just bogus, or the transport is in a state where it can't allocate resources for any request, there needs to be a way to kill the RPC right there and not loop. This immediately fixes a rare problem in the backchannel send path, which loops if the server happens to send a CB request whose call+reply size is larger than a page (which it shouldn't do yet). One more issue: looks like xprt_inject_disconnect was incorrectly placed in the failure path in call_allocate. It needs to be in the success path, as it is for other call-sites. Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker

SUNRPC: Refactor rpc_xdr_buf_init()

2016-09-19T17:08:37Z

Clean up: there is some XDR initialization logic that is common to the forward channel and backchannel. Move it to an XDR header so it can be shared. rpc_rqst::rq_buffer points to a buffer containing big-endian data. Update its annotation as part of the clean up. Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker

SUNRPC: Limit the reconnect backoff timer to the max RPC message timeout

2016-08-05T18:12:09Z

...and ensure that we propagate it to new transports on the same client. Signed-off-by: Trond Myklebust

rpc: share one xps between all backchannels

2016-06-15T14:32:25Z

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 Acked-by: Trond Myklebust

sunrpc: Advertise maximum backchannel payload size

2016-05-17T19:47:57Z

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 Tested-by: Steve Wise Signed-off-by: Anna Schumaker

SUNRPC: Add a structure to track multiple transports

2016-02-05T23:48:54Z

In order to support multipathing/trunking we will need the ability to track multiple transports. This patch sets up a basic structure for doing so. Signed-off-by: Trond Myklebust