kernel/include/linux/sunrpc/svc_rdma.h, branch linux-5.11.y

svcrdma: Use the new parsed chunk list when pulling Read chunks

2020-11-30T18:00:23Z

As a pre-requisite for handling multiple Read chunks in each Read list, convert svc_rdma_recv_read_chunk() to use the new parsed Read chunk list. Signed-off-by: Chuck Lever

svcrdma: Remove chunk list pointers

2020-11-30T18:00:23Z

Clean up: These pointers are no longer used. Signed-off-by: Chuck Lever

svcrdma: Support multiple Write chunks in svc_rdma_send_reply_chunk

2020-11-30T18:00:23Z

Refactor svc_rdma_send_reply_chunk() so that it Sends only the parts of rq_res that do not contain a result payload. Signed-off-by: Chuck Lever

svcrdma: Support multiple Write chunks in svc_rdma_map_reply_msg()

2020-11-30T18:00:23Z

Refactor: svc_rdma_map_reply_msg() is restructured to DMA map only the parts of rq_res that do not contain a result payload. This change has been tested to confirm that it does not cause a regression in the no Write chunk and single Write chunk cases. Multiple Write chunks have not been tested. Signed-off-by: Chuck Lever

svcrdma: Support multiple write chunks when pulling up

2020-11-30T18:00:22Z

When counting the number of SGEs needed to construct a Send request, do not count result payloads. And, when copying the Reply message into the pull-up buffer, result payloads are not to be copied to the Send buffer. Signed-off-by: Chuck Lever

svcrdma: Use parsed chunk lists to construct RDMA Writes

2020-11-30T18:00:22Z

Refactor: Instead of re-parsing the ingress RPC Call transport header when constructing RDMA Writes, use the new parsed chunk lists for the Write list and Reply chunk, which are version-agnostic and already XDR-decoded. Signed-off-by: Chuck Lever

svcrdma: Use parsed chunk lists to detect reverse direction replies

2020-11-30T18:00:22Z

Refactor: Don't duplicate header decoding smarts here. Instead, use the new parsed chunk lists. Note that the XID sanity test is also removed. The XID is already looked up by the cb handler, and is rejected if it's not recognized. Signed-off-by: Chuck Lever

svcrdma: Add a "parsed chunk list" data structure

2020-11-30T18:00:22Z

This simple data structure binds the location of each data payload inside of an RPC message to the chunk that will be used to push it to or pull it from the client. There are several benefits to this small additional overhead: * It enables support for more than one chunk in incoming Read and Write lists. * It translates the version-specific on-the-wire format into a generic in-memory structure, enabling support for multiple versions of the RPC/RDMA transport protocol. * It enables the server to re-organize a chunk list if it needs to adjust where Read chunk data lands in server memory without altering the contents of the XDR-encoded Receive buffer. Construction of these lists is done while sanity checking each incoming RPC/RDMA header. Subsequent patches will make use of the generated data structures. Signed-off-by: Chuck Lever

svcrdma: Post RDMA Writes while XDR encoding replies

2020-11-30T18:00:22Z

The only RPC/RDMA ordering requirement between RDMA Writes and RDMA Sends is that the responder must post the Writes on the Send queue before posting the Send that conveys the RPC Reply for that Write payload. The Linux NFS server implementation now has a transport method that can post result Payload Writes earlier than svc_rdma_sendto: ->xpo_result_payload() This gets RDMA Writes going earlier so they are more likely to be complete at the remote end before the Send completes. Some care must be taken with pulled-up Replies. We don't want to push the Write chunk and then send the same payload data via Send. Signed-off-by: Chuck Lever

SUNRPC: Rename svc_encode_read_payload()

2020-11-30T18:00:21Z

Clean up: "result payload" is a less confusing name for these payloads. "READ payload" reflects only the NFS usage. Signed-off-by: Chuck Lever