kernel/include/uapi/linux/if_xdp.h, branch linux-5.1.y

xsk: Fix umem fill/completion queue mmap on 32-bit

2018-06-07T22:18:02Z

With gcc-4.1.2 on 32-bit: net/xdp/xsk.c:663: warning: integer constant is too large for ‘long’ type net/xdp/xsk.c:665: warning: integer constant is too large for ‘long’ type Add the missing "ULL" suffixes to the large XDP_UMEM_PGOFF_*_RING values to fix this. net/xdp/xsk.c:663: warning: comparison is always false due to limited range of data type net/xdp/xsk.c:665: warning: comparison is always false due to limited range of data type "unsigned long" is 32-bit on 32-bit systems, hence the offset is truncated, and can never be equal to any of the XDP_UMEM_PGOFF_*_RING values. Use loff_t (and the required cast) to fix this. Fixes: 423f38329d267969 ("xsk: add umem fill queue support and mmap") Fixes: fe2308328cd2f26e ("xsk: add umem completion queue support and mmap") Signed-off-by: Geert Uytterhoeven Acked-by: Björn Töpel Signed-off-by: Daniel Borkmann

xsk: add zero-copy support for Rx

2018-06-05T13:46:55Z

Extend the xsk_rcv to support the new MEM_TYPE_ZERO_COPY memory, and wireup ndo_bpf call in bind. 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: 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: fill hole in struct sockaddr_xdp

2018-05-22T08:25:06Z

Move the sxdp_flags up, avoiding a hole in the uapi structure. 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

xsk: add Tx queue setup and mmap support

2018-05-03T22:55:24Z

Another setsockopt (XDP_TX_QUEUE) is added to let the process allocate a queue, where the user process can pass frames to be transmitted by the kernel. The mmapping of the queue is done using the XDP_PGOFF_TX_QUEUE offset. Signed-off-by: Magnus Karlsson Signed-off-by: Alexei Starovoitov

xsk: add umem completion queue support and mmap

2018-05-03T22:55:24Z

Here, we add another setsockopt for registered user memory (umem) called XDP_UMEM_COMPLETION_QUEUE. Using this socket option, the process can ask the kernel to allocate a queue (ring buffer) and also mmap it (XDP_UMEM_PGOFF_COMPLETION_QUEUE) into the process. The queue is used to explicitly pass ownership of umem frames from the kernel to user process. This will be used by the TX path to tell user space that a certain frame has been transmitted and user space can use it for something else, if it wishes. Signed-off-by: Magnus Karlsson Signed-off-by: Alexei Starovoitov

xsk: add support for bind for Rx

2018-05-03T22:55:23Z

Here, the bind syscall is added. Binding an AF_XDP socket, means associating the socket to an umem, a netdev and a queue index. This can be done in two ways. The first way, creating a "socket from scratch". Create the umem using the XDP_UMEM_REG setsockopt and an associated fill queue with XDP_UMEM_FILL_QUEUE. Create the Rx queue using the XDP_RX_QUEUE setsockopt. Call bind passing ifindex and queue index ("channel" in ethtool speak). The second way to bind a socket, is simply skipping the umem/netdev/queue index, and passing another already setup AF_XDP socket. The new socket will then have the same umem/netdev/queue index as the parent so it will share the same umem. You must also set the flags field in the socket address to XDP_SHARED_UMEM. v2: Use PTR_ERR instead of passing error variable explicitly. Signed-off-by: Magnus Karlsson Signed-off-by: Alexei Starovoitov