wireguard-linux/include/net/xsk_buff_pool.h, branch jd/bump-compilers

xsk: use generic DMA sync shortcut instead of a custom one

2024-05-08T06:51:20Z

XSk infra's been using its own DMA sync shortcut to try avoiding redundant function calls. Now that there is a generic one, remove the custom implementation and rely on the generic helpers. xsk_buff_dma_sync_for_cpu() doesn't need the second argument anymore, remove it. Signed-off-by: Alexander Lobakin Signed-off-by: Christoph Hellwig

xsk: add functions to fill control buffer

2023-12-14T00:16:40Z

Commit 94ecc5ca4dbf ("xsk: Add cb area to struct xdp_buff_xsk") has added a buffer for custom data to xdp_buff_xsk. Particularly, this memory is used for data, consumed by XDP hints kfuncs. It does not always change on a per-packet basis and some parts can be set for example, at the same time as RX queue info. Add functions to fill all cbs in xsk_buff_pool with the same metadata. Signed-off-by: Maciej Fijalkowski Signed-off-by: Larysa Zaremba Acked-by: Magnus Karlsson Link: https://lore.kernel.org/r/20231205210847.28460-8-larysa.zaremba@intel.com Signed-off-by: Alexei Starovoitov

xsk: Add option to calculate TX checksum in SW

2023-11-29T22:59:40Z

For XDP_COPY mode, add a UMEM option XDP_UMEM_TX_SW_CSUM to call skb_checksum_help in transmit path. Might be useful to debugging issues with real hardware. I also use this mode in the selftests. Signed-off-by: Stanislav Fomichev Link: https://lore.kernel.org/r/20231127190319.1190813-9-sdf@google.com Signed-off-by: Alexei Starovoitov

xsk: Add TX timestamp and TX checksum offload support

2023-11-29T22:59:40Z

This change actually defines the (initial) metadata layout that should be used by AF_XDP userspace (xsk_tx_metadata). The first field is flags which requests appropriate offloads, followed by the offload-specific fields. The supported per-device offloads are exported via netlink (new xsk-flags). The offloads themselves are still implemented in a bit of a framework-y fashion that's left from my initial kfunc attempt. I'm introducing new xsk_tx_metadata_ops which drivers are supposed to implement. The drivers are also supposed to call xsk_tx_metadata_request/xsk_tx_metadata_complete in the right places. Since xsk_tx_metadata_{request,_complete} are static inline, we don't incur any extra overhead doing indirect calls. The benefit of this scheme is as follows: - keeps all metadata layout parsing away from driver code - makes it easy to grep and see which drivers implement what - don't need any extra flags to maintain to keep track of what offloads are implemented; if the callback is implemented - the offload is supported (used by netlink reporting code) Two offloads are defined right now: 1. XDP_TXMD_FLAGS_CHECKSUM: skb-style csum_start+csum_offset 2. XDP_TXMD_FLAGS_TIMESTAMP: writes TX timestamp back into metadata area upon completion (tx_timestamp field) XDP_TXMD_FLAGS_TIMESTAMP is also implemented for XDP_COPY mode: it writes SW timestamp from the skb destructor (note I'm reusing hwtstamps to pass metadata pointer). The struct is forward-compatible and can be extended in the future by appending more fields. Reviewed-by: Song Yoong Siang Signed-off-by: Stanislav Fomichev Acked-by: Jakub Kicinski Link: https://lore.kernel.org/r/20231127190319.1190813-3-sdf@google.com Signed-off-by: Alexei Starovoitov

xsk: Support tx_metadata_len

2023-11-29T22:59:40Z

For zerocopy mode, tx_desc->addr can point to an arbitrary offset and carry some TX metadata in the headroom. For copy mode, there is no way currently to populate skb metadata. Introduce new tx_metadata_len umem config option that indicates how many bytes to treat as metadata. Metadata bytes come prior to tx_desc address (same as in RX case). The size of the metadata has mostly the same constraints as XDP: - less than 256 bytes - 8-byte aligned (compared to 4-byte alignment on xdp, due to 8-byte timestamp in the completion) - non-zero This data is not interpreted in any way right now. Reviewed-by: Song Yoong Siang Signed-off-by: Stanislav Fomichev Reviewed-by: Jakub Kicinski Link: https://lore.kernel.org/r/20231127190319.1190813-2-sdf@google.com Signed-off-by: Alexei Starovoitov

xsk: support mbuf on ZC RX

2023-07-19T16:56:49Z

Given that skb_shared_info relies on skb_frag_t, in order to support xskb chaining, introduce xdp_buff_xsk::xskb_list_node and xsk_buff_pool::xskb_list. This is needed so ZC drivers can add frags as xskb nodes which will make it possible to handle it both when producing AF_XDP Rx descriptors as well as freeing/recycling all the frags that a single frame carries. Speaking of latter, update xsk_buff_free() to take care of list nodes. For the former (adding as frags), introduce xsk_buff_add_frag() for ZC drivers usage that is going to be used to add a frag to xskb list from pool. xsk_buff_get_frag() will be utilized by XDP_TX and, on contrary, will return xdp_buff. One of the previous patches added a wrapper for ZC Rx so implement xskb list walk and production of Rx descriptors there. On bind() path, bail out if socket wants to use ZC multi-buffer but underlying netdev does not support it. Signed-off-by: Maciej Fijalkowski Link: https://lore.kernel.org/r/20230719132421.584801-12-maciej.fijalkowski@intel.com Signed-off-by: Alexei Starovoitov

xsk: allow core/drivers to test EOP bit

2023-07-19T16:56:49Z

Drivers are used to check for EOP bit whereas AF_XDP operates on inverted logic - user space indicates that current frag is not the last one and packet continues. For AF_XDP core needs, add xp_mb_desc() that will simply test XDP_PKT_CONTD from xdp_desc::options, but in order to preserve drivers default behavior, introduce an interface for ZC drivers that will negate xp_mb_desc() result and therefore make it easier to test EOP bit from during production of HW Tx descriptors. Signed-off-by: Maciej Fijalkowski Link: https://lore.kernel.org/r/20230719132421.584801-8-maciej.fijalkowski@intel.com Signed-off-by: Alexei Starovoitov

xsk: Use pool->dma_pages to check for DMA

2023-04-27T20:24:51Z

Compare pool->dma_pages instead of pool->dma_pages_cnt to check for an active DMA mapping. pool->dma_pages needs to be read anyway to access the map so this compiles to more efficient code. Signed-off-by: Kal Conley Signed-off-by: Daniel Borkmann Reviewed-by: Xuan Zhuo Acked-by: Magnus Karlsson Link: https://lore.kernel.org/bpf/20230423180157.93559-1-kal.conley@dectris.com

xsk: Fix unaligned descriptor validation

2023-04-06T16:53:05Z

Make sure unaligned descriptors that straddle the end of the UMEM are considered invalid. Currently, descriptor validation is broken for zero-copy mode which only checks descriptors at page granularity. For example, descriptors in zero-copy mode that overrun the end of the UMEM but not a page boundary are (incorrectly) considered valid. The UMEM boundary check needs to happen before the page boundary and contiguity checks in xp_desc_crosses_non_contig_pg(). Do this check in xp_unaligned_validate_desc() instead like xp_check_unaligned() already does. Fixes: 2b43470add8c ("xsk: Introduce AF_XDP buffer allocation API") Signed-off-by: Kal Conley Acked-by: Magnus Karlsson Link: https://lore.kernel.org/r/20230405235920.7305-2-kal.conley@dectris.com Signed-off-by: Martin KaFai Lau

xsk: Add cb area to struct xdp_buff_xsk

2023-01-23T17:58:23Z

Add an area after the xdp_buff in struct xdp_buff_xsk that drivers can use to stash extra information to use in metadata kfuncs. The maximum size of 24 bytes means the full xdp_buff_xsk structure will take up exactly two cache lines (with the cb field spanning both). Also add a macro drivers can use to check their own wrapping structs against the available size. Cc: John Fastabend Cc: David Ahern Cc: Martin KaFai Lau Cc: Jakub Kicinski Cc: Willem de Bruijn Cc: Jesper Dangaard Brouer Cc: Anatoly Burakov Cc: Alexander Lobakin Cc: Magnus Karlsson Cc: Maryam Tahhan Cc: xdp-hints@xdp-project.net Cc: netdev@vger.kernel.org Suggested-by: Jakub Kicinski Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Stanislav Fomichev Link: https://lore.kernel.org/r/20230119221536.3349901-15-sdf@google.com Signed-off-by: Martin KaFai Lau