9a0f2079ca
Most of code used for Rx ring initialization could be reused in NETMAP. Reset of NETMAP ring and new alloc method was added. Driver decides if use kernels mbufs or NETMAPs slots based on IFCAP_NETMAP flag. It allows to reuse ena_refill_rx_bufs, which provides proper handling of Rx out of order completion. ena_netmap_alloc_rx_slot takes exactly the same arguments as ena_alloc_rx_mbuf, but instead of allocating one mbuf it takes one slot from NETMAP ring. Based on queue id proper netmap_ring is found. As NETMAP provides the "partial opening" feature not all of the rings are avaiable. Not used points to invalid ring. If there is available slot, it is taken from the ring. Its buffer is mapped to DMA and its index is stored in ena_rx_buffer field in ena_rx_buffer structure. Then ena_buf is filled with addresses and ring state is updated. Cleanup is handled by ena_netmap_free_rx_slot. It unmaps DMA and returns buffer to ring. As we could not return more bufs than we have taken and we should not override occupied slots, buf_index should be 0. It is being checked by assertion. ena_netmap_rxsync callback puts received packets back to NETMAP ring and passes them to user space by updating ring pointers. First it fills ena_netmap_ctx. Then it performs two actions: * ena_netmap_rx_frames moves received frames from NIC to NETMAP ring, * ena_netmap_rx_cleanup fills NIC ring with slots released by userspace app. In case of Rx error that could be handled by NIC driver (for example by performing reset) rx sync should return 0. ena_netmap_rx_frames first checks if NETMAP ring is in consistent state and then in the loop receives new frames. When all available frames are taken nr_hwtail is updated. Receiving one frame is handled by ena_netmap_rx_frame. If no error occurrs, each Descriptor is loaded by ena_netmap_rx_load_desc function. If packets take more than one segments NS_MOREFRAG flag must be set in all, but not last slot. In case of wrong req_id packet is removed from NETMAP ring. If packet is successful received counters are updated. Refiling of NIC ring is performed by ena_netmap_rx_cleanup function. It calculates number of available slots and call ena_refill_rx_bufs with proper number. Differential Revision: https://reviews.freebsd.org/D21935 Submitted by: Rafal Kozik <rk@semihalf.com> Michal Krawczyk <mk@semihalf.com> Obtained from: Semihalf Sponsored by: Amazon, Inc. |
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| .. | ||
| ena_datapath.c | ||
| ena_datapath.h | ||
| ena_netmap.c | ||
| ena_netmap.h | ||
| ena_sysctl.c | ||
| ena_sysctl.h | ||
| ena.c | ||
| ena.h | ||