kernel.git/net/xdp/xsk_queue.h, branch linux-4.18.y

xsk: fix poll/POLLIN premature returns

2018-07-26T00:53:10Z

Polling for the ingress queues relies on reading the producer/consumer pointers of the Rx queue. Prior this commit, a cached consumer pointer could be used, instead of the actual consumer pointer and therefore report POLLIN prematurely. This patch makes sure that the non-cached consumer pointer is used instead. Reported-by: Qi Zhang Tested-by: Qi Zhang Fixes: c497176cb2e4 ("xsk: add Rx receive functions and poll support") Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann

xsk: fix potential lost completion message in SKB path

2018-07-03T01:37:11Z

The code in xskq_produce_addr erroneously checked if there was up to LAZY_UPDATE_THRESHOLD amount of space in the completion queue. It only needs to check if there is one slot left in the queue. This bug could under some circumstances lead to a WARN_ON_ONCE being triggered and the completion message to user space being lost. Fixes: 35fcde7f8deb ("xsk: support for Tx") Signed-off-by: Magnus Karlsson Reported-by: Pavel Odintsov Signed-off-by: Alexei Starovoitov

xsk: wire upp Tx zero-copy functions

2018-06-05T13:48:34Z

Here we add the functionality required to support zero-copy Tx, and also exposes various zero-copy related functions for the netdevs. Signed-off-by: Magnus Karlsson Signed-off-by: Daniel Borkmann

xsk: moved struct xdp_umem definition

2018-06-05T13:45:17Z

Moved struct xdp_umem to xdp_sock.h, in order to prepare for zero-copy support. Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann

xsk: new descriptor addressing scheme

2018-06-04T15:21:02Z

Currently, AF_XDP only supports a fixed frame-size memory scheme where each frame is referenced via an index (idx). A user passes the frame index to the kernel, and the kernel acts upon the data. Some NICs, however, do not have a fixed frame-size model, instead they have a model where a memory window is passed to the hardware and multiple frames are filled into that window (referred to as the "type-writer" model). By changing the descriptor format from the current frame index addressing scheme, AF_XDP can in the future be extended to support these kinds of NICs. In the index-based model, an idx refers to a frame of size frame_size. Addressing a frame in the UMEM is done by offseting the UMEM starting address by a global offset, idx * frame_size + offset. Communicating via the fill- and completion-rings are done by means of idx. In this commit, the idx is removed in favor of an address (addr), which is a relative address ranging over the UMEM. To convert an idx-based address to the new addr is simply: addr = idx * frame_size + offset. We also stop referring to the UMEM "frame" as a frame. Instead it is simply called a chunk. To transfer ownership of a chunk to the kernel, the addr of the chunk is passed in the fill-ring. Note, that the kernel will mask addr to make it chunk aligned, so there is no need for userspace to do that. E.g., for a chunk size of 2k, passing an addr of 2048, 2050 or 3000 to the fill-ring will refer to the same chunk. On the completion-ring, the addr will match that of the Tx descriptor, passed to the kernel. Changing the descriptor format to use chunks/addr will allow for future changes to move to a type-writer based model, where multiple frames can reside in one chunk. In this model passing one single chunk into the fill-ring, would potentially result in multiple Rx descriptors. This commit changes the uapi of AF_XDP sockets, and updates the documentation. Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann

xsk: proper fill queue descriptor validation

2018-06-04T15:21:02Z

Previously the fill queue descriptor was not copied to kernel space prior validating it, making it possible for userland to change the descriptor post-kernel-validation. Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann

xsk: remove explicit ring structure from uapi

2018-05-22T08:25:06Z

In this commit we remove the explicit ring structure from the the uapi. It is tricky for an uapi to depend on a certain L1 cache line size, since it can differ for variants of the same architecture. Now, we let the user application determine the offsets of the producer, consumer and descriptors by asking the socket via getsockopt. A typical flow would be (Rx ring): struct xdp_mmap_offsets off; struct xdp_desc *ring; u32 *prod, *cons; void *map; ... getsockopt(fd, SOL_XDP, XDP_MMAP_OFFSETS, &off, &optlen); map = mmap(NULL, off.rx.desc + NUM_DESCS * sizeof(struct xdp_desc), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, sfd, XDP_PGOFF_RX_RING); prod = map + off.rx.producer; cons = map + off.rx.consumer; ring = map + off.rx.desc; Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann

xsk: fixed some cases of unnecessary parentheses

2018-05-18T14:07:03Z

Removed some cases of unnecessary parentheses. Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann

xsk: clean up SPDX headers

2018-05-18T14:07:02Z

Clean up SPDX-License-Identifier and removing licensing leftovers. Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann

xsk: statistics support

2018-05-03T22:55:25Z

In this commit, a new getsockopt is added: XDP_STATISTICS. This is used to obtain stats from the sockets. v2: getsockopt now returns size of stats structure. Signed-off-by: Magnus Karlsson Signed-off-by: Alexei Starovoitov