Lines Matching +full:rx +full:- +full:shared
1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
4 * Copyright (C) 2011-2014 Matteo Landi, Luigi Rizzo. All rights reserved.
48 * Some fields should be cache-aligned to reduce contention.
56 * --- Netmap data structures ---
68 +---->+---------------+
71 +----------------+ / | other fields |
75 | | / +---------------+
77 | txring_ofs[0] | (rel.to nifp)--' | flags, ptr |
78 | txring_ofs[1] | +---------------+
80 | txring_ofs[t] | | buf_idx, len | slot[n-1]
81 +----------------+ | flags, ptr |
82 | rxring_ofs[0] | +---------------+
84 (rx+hrx entries)
86 +----------------+
92 * There is one netmap_ring per physical NIC ring, plus at least one tx/rx ring
93 * pair attached to the host stack (these pairs are unused for non-NIC ports).
96 * so that zero-copy can be implemented between them.
99 * The netmap_ring is the userspace-visible replica of the NIC ring.
100 * Each slot has the index of a buffer (MTU-sized and residing in the
101 * mmapped region), its length and some flags. An extra 64-bit pointer
102 * is provided for user-supplied buffers in the tx path.
113 * mapped, nifp->ni_bufs_head will be the index of the first buffer.
132 * netmap:foo^k the k-th host rings pair
134 * netmap:foo-k the k-th NIC rings pair
140 * + The RX host rings are used to store those packets that the host network
145 * mbufs in the RX host rings; the netmap port should be registered with
152 * ifconfig on FreeBSD or ethtool -K on Linux) for an interface that is being
154 * unchecksummed packets may be dropped immediately or end up in the host RX
194 * (Only for physical ports, rx rings with NR_FORWARD set).
195 * Slot released to the kernel (i.e. before ring->head) with
197 * thus restoring the host-NIC connection for these slots.
217 * Set on all but the last slot of a multi-segment packet.
234 #define NS_RFRAGS(_slot) ( ((_slot)->flags >> 8) & 0xff)
236 * (VALE rx rings only) the high 8 bits
246 * Netmap representation of a TX or RX ring (also known as "queue").
247 * This is a queue implemented as a fixed-size circular array.
257 * [head .. tail-1] can be used for new packets to send;
261 * for new transmissions. XXX todo (2014-03-12)
263 * In RX rings:
270 * [head .. tail-1] contain received packets;
278 * [head .. tail-1] are owned by the user program;
294 const uint16_t dir; /* 0: tx, 1: rx */
313 * account when specifying buffer-offsets in TX slots.
349 * Check if space is available in the ring. We use ring->head, which
351 * possible that the applications moves ring->cur ahead of ring->tail
352 * (e.g., by setting ring->cur <== ring->tail), if it wants more slots
359 return (ring->head == ring->tail); in nm_ring_empty()
381 * Physical NICs can have different numbers of tx and rx rings.
387 const uint32_t ni_rx_rings; /* number of HW rx rings */
391 const uint32_t ni_host_rx_rings; /* number of SW rx rings */
396 * - NIC tx rings (ni_tx_rings);
397 * - host tx rings (ni_host_tx_rings);
398 * - NIC rx rings (ni_rx_rings);
399 * - host rx ring (ni_host_rx_rings);
431 * Pointer to a command-specific struct, described by one
444 * On input, non-zero values may be used to reconfigure the port
454 * If nr_mode == NR_REG_ONE_NIC (only a single couple of TX/RX
455 * rings), indicate which NIC TX and/or RX ring is to be bound
456 * (0..nr_*x_rings-1).
461 * NR_NO_TX_POLL can be OR-ed to make select()/poll() push
465 * NR_DO_RX_POLL can be OR-ed to make select()/poll() release
466 * packets on rx rings also when POLLIN is NOT set.
467 * The default is to touch the rx ring only with POLLIN.
480 * Region '1' is the global allocator, normally shared
482 * If two ports the same region zero-copy is possible.
506 * (e.g. because they contain arrays). For fixed-size options this
519 uint64_t nr_options; /* command-specific options */
534 /* Set the port header length (was virtio-net header length). */
536 /* Get the port header length (was virtio-net header length). */
548 /* Start an in-kernel loop that syncs the rings periodically or
552 /* Stops the thread executing the in-kernel loop. The thread
561 * from user-space allocated memory pools (e.g. hugepages).
565 /* ON NETMAP_REQ_SYNC_KLOOP_START, ask netmap to use eventfd-based
572 * struct netmap_ring header, but rather using an user-provided
578 * if the TX and/or RX rings are synced in the context of the VM exit.
599 uint64_t nr_offset; /* nifp offset in the shared region */
600 uint64_t nr_memsize; /* size of the shared region */
602 uint32_t nr_rx_slots; /* slots in rx rings */
604 uint16_t nr_rx_rings; /* number of rx rings */
606 uint16_t nr_host_rx_rings; /* number of host rx rings */
623 /* Applications set this flag if they are able to deal with virtio-net headers,
624 * that is send/receive frames that start with a virtio-net header.
647 /* A single ioctl number is shared by all the new API command.
654 /* The ioctl commands to sync TX/RX netmap rings.
655 * NIOCTXSYNC, NIOCRXSYNC synchronize tx or rx queues,
659 #define NIOCRXSYNC _IO('i', 149) /* sync rx queues */
669 uint64_t nr_memsize; /* size of the shared region */
671 uint32_t nr_rx_slots; /* slots in rx rings */
673 uint16_t nr_rx_rings; /* number of rx rings */
675 uint16_t nr_host_rx_rings; /* number of host rx rings */
734 uint32_t nr_rx_slots; /* slots in rx rings */
736 uint16_t nr_rx_rings; /* number of rx rings */
778 * Start an in-kernel loop that syncs the rings periodically or on
792 /* A CSB entry for the application --> kernel direction. */
796 uint32_t appl_need_kick; /* AW+ KR+ kern --> appl notification enable */
797 uint32_t sync_flags; /* AW+ KR+ the flags of the appl [tx|rx]sync() */
801 /* A CSB entry for the application <-- kernel direction. */
805 uint32_t kern_need_kick; /* AR+ KW+ appl-->kern notification enable */
819 * effect of a store-store barrier and a load-store barrier, in nm_stst_barrier()
826 * effect of a load-load barrier and a store-load barrier, in nm_ldld_barrier()
863 /* Application side of sync-kloop: Write ring pointers (cur, head) to the CSB.
869 /* Issue a first store-store barrier to make sure writes to the in nm_sync_kloop_appl_write()
870 * netmap ring do not overcome updates on atok->cur and atok->head. */ in nm_sync_kloop_appl_write()
890 * wmb() <-----------> rmb() in nm_sync_kloop_appl_write()
894 atok->cur = cur; in nm_sync_kloop_appl_write()
896 atok->head = head; in nm_sync_kloop_appl_write()
899 /* Application side of sync-kloop: Read kring pointers (hwcur, hwtail) from
910 *hwtail = ktoa->hwtail; in nm_sync_kloop_appl_read()
912 *hwcur = ktoa->hwcur; in nm_sync_kloop_appl_read()
914 /* Make sure that loads from ktoa->hwtail and ktoa->hwcur are not delayed in nm_sync_kloop_appl_read()
938 /* Notifier for the application --> kernel loop direction. */
940 /* Notifier for the kernel loop --> application direction. */
961 /* Array of CSB entries for application --> kernel communication
965 /* Array of CSB entries for kernel --> application communication
974 * going to put into the offset slot-fields. Any larger value