On 08/08, Breno Leitao wrote: > This patchset adds support for getsockopt (SOCKET_URING_OP_GETSOCKOPT) > and setsockopt (SOCKET_URING_OP_SETSOCKOPT) in io_uring commands. > SOCKET_URING_OP_SETSOCKOPT implements generic case, covering all levels > nad optnames. On the other hand, SOCKET_URING_OP_GETSOCKOPT just > implements level SOL_SOCKET case, which seems to be the > most common level parameter for get/setsockopt(2). > > struct proto_ops->setsockopt() uses sockptr instead of userspace > pointers, which makes it easy to bind to io_uring. Unfortunately > proto_ops->getsockopt() callback uses userspace pointers, except for > SOL_SOCKET, which is handled by sk_getsockopt(). Thus, this patchset > leverages sk_getsockopt() to imlpement the SOCKET_URING_OP_GETSOCKOPT > case. > > In order to support BPF hooks, I modified the hooks to use sockptr, so, > it is flexible enough to accept user or kernel pointers for > optval/optlen. > > PS1: For getsockopt command, the optlen field is not a userspace > pointers, but an absolute value, so this is slightly different from > getsockopt(2) behaviour. The new optlen value is returned in cqe->res. > > PS2: The userspace pointers need to be alive until the operation is > completed. > > These changes were tested with a new test[1] in liburing. On the BPF > side, I tested that no regression was introduced by running "test_progs" > self test using "sockopt" test case. > > [1] Link: https://github.com/leitao/liburing/blob/getsock/test/socket-getsetsock-cmd.c > > RFC -> V1: > * Copy user memory at io_uring subsystem, and call proto_ops > callbacks using kernel memory > * Implement all the cases for SOCKET_URING_OP_SETSOCKOPT I did a quick pass, will take a close look later today. So far everything makes sense to me. Should we properly test it as well? We have tools/testing/selftests/bpf/prog_tests/sockopt.c which does most of the sanity checks, but it uses regular socket/{g,s}etsockopt syscalls. Seems like it should be pretty easy to extend this with io_uring path? tools/testing/selftests/net/io_uring_zerocopy_tx.c already implements minimal wrappers which we can most likely borrow.
