/*- * SPDX-License-Identifier: BSD-2-Clause * * Copyright (C) 2011-2014 Matteo Landi, Luigi Rizzo. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``S IS''AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * * Definitions of constants and the structures used by the netmap * framework, for the part visible to both kernel and userspace. * Detailed info on netmap is available with "man netmap" or at * * http://info.iet.unipi.it/~luigi/netmap/ * * This API is also used to communicate with the VALE software switch */ #ifndef _NET_NETMAP_H_ #define _NET_NETMAP_H_ #define NETMAP_API 14 /* current API version */ #define NETMAP_MIN_API 14 /* min and max versions accepted */ #define NETMAP_MAX_API 15 /* * Some fields should be cache-aligned to reduce contention. * The alignment is architecture and OS dependent, but rather than * digging into OS headers to find the exact value we use an estimate * that should cover most architectures. */ #define NM_CACHE_ALIGN 128 /* * --- Netmap data structures --- * * The userspace data structures used by netmap are shown below. * They are allocated by the kernel and mmap()ed by userspace threads. * Pointers are implemented as memory offsets or indexes, * so that they can be easily dereferenced in kernel and userspace. KERNEL (opaque, obviously) ==================================================================== | USERSPACE | struct netmap_ring +---->+---------------+ / | head,cur,tail | struct netmap_if (nifp, 1 per fd) / | buf_ofs | +----------------+ / | other fields | | ni_tx_rings | / +===============+ | ni_rx_rings | / | buf_idx, len | slot[0] | | / | flags, ptr | | | / +---------------+ +================+ / | buf_idx, len | slot[1] | txring_ofs[0] | (rel.to nifp)--' | flags, ptr | | txring_ofs[1] | +---------------+ (tx+htx entries) (num_slots entries) | txring_ofs[t] | | buf_idx, len | slot[n-1] +----------------+ | flags, ptr | | rxring_ofs[0] | +---------------+ | rxring_ofs[1] | (rx+hrx entries) | rxring_ofs[r] | +----------------+ * For each "interface" (NIC, host stack, PIPE, VALE switch port) bound to * a file descriptor, the mmap()ed region contains a (logically readonly) * struct netmap_if pointing to struct netmap_ring's. * * There is one netmap_ring per physical NIC ring, plus at least one tx/rx ring * pair attached to the host stack (these pairs are unused for non-NIC ports). * * All physical/host stack ports share the same memory region, * so that zero-copy can be implemented between them. * VALE switch ports instead have separate memory regions. * * The netmap_ring is the userspace-visible replica of the NIC ring. * Each slot has the index of a buffer (MTU-sized and residing in the * mmapped region), its length and some flags. An extra 64-bit pointer * is provided for user-supplied buffers in the tx path. * * In user space, the buffer address is computed as * (char *)ring + buf_ofs + index * NETMAP_BUF_SIZE * * Added in NETMAP_API 11: * * + NIOCREGIF can request the allocation of extra spare buffers from * the same memory pool. The desired number of buffers must be in * nr_arg3. The ioctl may return fewer buffers, depending on memory * availability. nr_arg3 will return the actual value, and, once * mapped, nifp->ni_bufs_head will be the index of the first buffer. * * The buffers are linked to each other using the first uint32_t * as the index. On close, ni_bufs_head must point to the list of * buffers to be released. * * + NIOCREGIF can attach to PIPE rings sharing the same memory * space with a parent device. The ifname indicates the parent device, * which must already exist. Flags in nr_flags indicate if we want to * bind the master or slave side, the index (from nr_ringid) * is just a cookie and does not need to be sequential. * * + NIOCREGIF can also attach to 'monitor' rings that replicate * the content of specific rings, also from the same memory space. * * Extra flags in nr_flags support the above functions. * Application libraries may use the following naming scheme: * netmap:foo all NIC rings pairs * netmap:foo^ only host rings pairs * netmap:foo^k the k-th host rings pair * netmap:foo+ all NIC rings + host rings pairs * netmap:foo-k the k-th NIC rings pair * netmap:foo{k PIPE rings pair k, master side * netmap:foo}k PIPE rings pair k, slave side * * Some notes about host rings: * * + The RX host rings are used to store those packets that the host network * stack is trying to transmit through a NIC queue, but only if that queue * is currently in netmap mode. Netmap will not intercept host stack mbufs * designated to NIC queues that are not in netmap mode. As a consequence, * registering a netmap port with netmap:foo^ is not enough to intercept * mbufs in the RX host rings; the netmap port should be registered with * netmap:foo*, or another registration should be done to open at least a * NIC TX queue in netmap mode. * * + Netmap is not currently able to deal with intercepted transmit mbufs which * require offloadings like TSO, UFO, checksumming offloadings, etc. It is * responsibility of the user to disable those offloadings (e.g. using * ifconfig on FreeBSD or ethtool -K on Linux) for an interface that is being * used in netmap mode. If the offloadings are not disabled, GSO and/or * unchecksummed packets may be dropped immediately or end up in the host RX * rings, and will be dropped as soon as the packet reaches another netmap * adapter. */ /* * struct netmap_slot is a buffer descriptor */ struct netmap_slot { uint32_t buf_idx; /* buffer index */ uint16_t len; /* length for this slot */ uint16_t flags; /* buf changed, etc. */ uint64_t ptr; /* pointer for indirect buffers */ }; /* * The following flags control how the slot is used */ #define NS_BUF_CHANGED 0x0001 /* buf_idx changed */ /* * must be set whenever buf_idx is changed (as it might be * necessary to recompute the physical address and mapping) * * It is also set by the kernel whenever the buf_idx is * changed internally (e.g., by pipes). Applications may * use this information to know when they can reuse the * contents of previously prepared buffers. */ #define NS_REPORT 0x0002 /* ask the hardware to report results */ /* * Request notification when slot is used by the hardware. * Normally transmit completions are handled lazily and * may be unreported. This flag lets us know when a slot * has been sent (e.g. to terminate the sender). */ #define NS_FORWARD 0x0004 /* pass packet 'forward' */ /* * (Only for physical ports, rx rings with NR_FORWARD set). * Slot released to the kernel (i.e. before ring->head) with * this flag set are passed to the peer ring (host/NIC), * thus restoring the host-NIC connection for these slots. * This supports efficient traffic monitoring or firewalling. */ #define NS_NO_LEARN 0x0008 /* disable bridge learning */ /* * On a VALE switch, do not 'learn' the source port for * this buffer. */ #define NS_INDIRECT 0x0010 /* userspace buffer */ /* * (VALE tx rings only) data is in a userspace buffer, * whose address is in the 'ptr' field in the slot. */ #define NS_MOREFRAG 0x0020 /* packet has more fragments */ /* * (VALE ports, ptnetmap ports and some NIC ports, e.g. * ixgbe and i40e on Linux) * Set on all but the last slot of a multi-segment packet. * The 'len' field refers to the individual fragment. */ #define NS_TXMON 0x0040 /* (monitor ports only) the packet comes from the TX * ring of the monitored port */ #define NS_PORT_SHIFT 8 #define NS_PORT_MASK (0xff << NS_PORT_SHIFT) /* * The high 8 bits of the flag, if not zero, indicate the * destination port for the VALE switch, overriding * the lookup table. */ #define NS_RFRAGS(_slot) ( ((_slot)->flags >> 8) & 0xff) /* * (VALE rx rings only) the high 8 bits * are the number of fragments. */ #define NETMAP_MAX_FRAGS 64 /* max number of fragments */ /* * struct netmap_ring * * Netmap representation of a TX or RX ring (also known as "queue"). * This is a queue implemented as a fixed-size circular array. * At the software level the important fields are: head, cur, tail. * * In TX rings: * * head first slot available for transmission. * cur wakeup point. select() and poll() will unblock * when 'tail' moves past 'cur' * tail (readonly) first slot reserved to the kernel * * [head .. tail-1] can be used for new packets to send; * 'head' and 'cur' must be incremented as slots are filled * with new packets to be sent; * 'cur' can be moved further ahead if we need more space * for new transmissions. XXX todo (2014-03-12) * * In RX rings: * * head first valid received packet * cur wakeup point. select() and poll() will unblock * when 'tail' moves past 'cur' * tail (readonly) first slot reserved to the kernel * * [head .. tail-1] contain received packets; * 'head' and 'cur' must be incremented as slots are consumed * and can be returned to the kernel; * 'cur' can be moved further ahead if we want to wait for * new packets without returning the previous ones. * * DATA OWNERSHIP/LOCKING: * The netmap_ring, and all slots and buffers in the range * [head .. tail-1] are owned by the user program; * the kernel only accesses them during a netmap system call * and in the user thread context. * * Other slots and buffers are reserved for use by the kernel */ struct netmap_ring { /* * buf_ofs is meant to be used through macros. * It contains the offset of the buffer region from this * descriptor. */ const int64_t buf_ofs; const uint32_t num_slots; /* number of slots in the ring. */ const uint32_t nr_buf_size; const uint16_t ringid; const uint16_t dir; /* 0: tx, 1: rx */ uint32_t head; /* (u) first user slot */ uint32_t cur; /* (u) wakeup point */ uint32_t tail; /* (k) first kernel slot */ uint32_t flags; struct timeval ts; /* (k) time of last *sync() */ /* offset_mask is used to isolate the part of the ptr field * in the slots used to contain an offset in the buffer. * It is zero if the ring has not be opened using the * NETMAP_REQ_OPT_OFFSETS option. */ const uint64_t offset_mask; /* the alignment requirement, in bytes, for the start * of the packets inside the buffers. * User programs should take this alignment into * account when specifying buffer-offsets in TX slots. */ const uint64_t buf_align; /* opaque room for a mutex or similar object */ #if !defined(_WIN32) || defined(__CYGWIN__) uint8_t __attribute__((__aligned__(NM_CACHE_ALIGN))) sem[128]; #else uint8_t __declspec(align(NM_CACHE_ALIGN)) sem[128]; #endif /* the slots follow. This struct has variable size */ struct netmap_slot slot[0]; /* array of slots. */ }; /* * RING FLAGS */ #define NR_TIMESTAMP 0x0002 /* set timestamp on *sync() */ /* * updates the 'ts' field on each netmap syscall. This saves * saves a separate gettimeofday(), and is not much worse than * software timestamps generated in the interrupt handler. */ #define NR_FORWARD 0x0004 /* enable NS_FORWARD for ring */ /* * Enables the NS_FORWARD slot flag for the ring. */ /* * Helper functions for kernel and userspace */ /* * Check if space is available in the ring. We use ring->head, which * points to the next netmap slot to be published to netmap. It is * possible that the applications moves ring->cur ahead of ring->tail * (e.g., by setting ring->cur <== ring->tail), if it wants more slots * than the ones currently available, and it wants to be notified when * more arrive. See netmap(4) for more details and examples. */ static inline int nm_ring_empty(struct netmap_ring *ring) { return (ring->head == ring->tail); } /* * Netmap representation of an interface and its queue(s). * This is initialized by the kernel when binding a file * descriptor to a port, and should be considered as readonly * by user programs. The kernel never uses it. * * There is one netmap_if for each file descriptor on which we want * to select/poll. * select/poll operates on one or all pairs depending on the value of * nmr_queueid passed on the ioctl. */ struct netmap_if { char ni_name[IFNAMSIZ]; /* name of the interface. */ const uint32_t ni_version; /* API version, currently unused */ const uint32_t ni_flags; /* properties */ #define NI_PRIV_MEM 0x1 /* private memory region */ /* * The number of packet rings available in netmap mode. * Physical NICs can have different numbers of tx and rx rings. * Physical NICs also have at least a 'host' rings pair. * Additionally, clients can request additional ring pairs to * be used for internal communication. */ const uint32_t ni_tx_rings; /* number of HW tx rings */ const uint32_t ni_rx_rings; /* number of HW rx rings */ uint32_t ni_bufs_head; /* head index for extra bufs */ const uint32_t ni_host_tx_rings; /* number of SW tx rings */ const uint32_t ni_host_rx_rings; /* number of SW rx rings */ uint32_t ni_spare1[3]; /* * The following array contains the offset of each netmap ring * from this structure, in the following order: * - NIC tx rings (ni_tx_rings); * - host tx rings (ni_host_tx_rings); * - NIC rx rings (ni_rx_rings); * - host rx ring (ni_host_rx_rings); * * The area is filled up by the kernel on NETMAP_REQ_REGISTER, * and then only read by userspace code. */ const ssize_t ring_ofs[0]; }; /* Legacy interface to interact with a netmap control device. * Included for backward compatibility. The user should not include this * file directly. */ #include "netmap_legacy.h" /* * New API to control netmap control devices. New applications should only use * nmreq_xyz structs with the NIOCCTRL ioctl() command. * * NIOCCTRL takes a nmreq_header struct, which contains the required * API version, the name of a netmap port, a command type, and pointers * to request body and options. * * nr_name (in) * The name of the port (em0, valeXXX:YYY, eth0{pn1 etc.) * * nr_version (in/out) * Must match NETMAP_API as used in the kernel, error otherwise. * Always returns the desired value on output. * * nr_reqtype (in) * One of the NETMAP_REQ_* command types below * * nr_body (in) * Pointer to a command-specific struct, described by one * of the struct nmreq_xyz below. * * nr_options (in) * Command specific options, if any. * * A NETMAP_REQ_REGISTER command activates netmap mode on the netmap * port (e.g. physical interface) specified by nmreq_header.nr_name. * The request body (struct nmreq_register) has several arguments to * specify how the port is to be registered. * * nr_tx_slots, nr_tx_slots, nr_tx_rings, nr_rx_rings, * nr_host_tx_rings, nr_host_rx_rings (in/out) * On input, non-zero values may be used to reconfigure the port * according to the requested values, but this is not guaranteed. * On output the actual values in use are reported. * * nr_mode (in) * Indicate what set of rings must be bound to the netmap * device (e.g. all NIC rings, host rings only, NIC and * host rings, ...). Values are in NR_REG_*. * * nr_ringid (in) * If nr_mode == NR_REG_ONE_NIC (only a single couple of TX/RX * rings), indicate which NIC TX and/or RX ring is to be bound * (0..nr_*x_rings-1). * * nr_flags (in) * Indicate special options for how to open the port. * * NR_NO_TX_POLL can be OR-ed to make select()/poll() push * packets on tx rings only if POLLOUT is set. * The default is to push any pending packet. * * NR_DO_RX_POLL can be OR-ed to make select()/poll() release * packets on rx rings also when POLLIN is NOT set. * The default is to touch the rx ring only with POLLIN. * Note that this is the opposite of TX because it * reflects the common usage. * * Other options are NR_MONITOR_TX, NR_MONITOR_RX, NR_ZCOPY_MON, * NR_EXCLUSIVE, NR_RX_RINGS_ONLY, NR_TX_RINGS_ONLY and * NR_ACCEPT_VNET_HDR. * * nr_mem_id (in/out) * The identity of the memory region used. * On input, 0 means the system decides autonomously, * other values may try to select a specific region. * On return the actual value is reported. * Region '1' is the global allocator, normally shared * by all interfaces. Other values are private regions. * If two ports the same region zero-copy is possible. * * nr_extra_bufs (in/out) * Number of extra buffers to be allocated. * * The other NETMAP_REQ_* commands are described below. * */ /* maximum size of a request, including all options */ #define NETMAP_REQ_MAXSIZE 4096 /* Header common to all request options. */ struct nmreq_option { /* Pointer to the next option. */ uint64_t nro_next; /* Option type. */ uint32_t nro_reqtype; /* (out) status of the option: * 0: recognized and processed * !=0: errno value */ uint32_t nro_status; /* Option size, used only for options that can have variable size * (e.g. because they contain arrays). For fixed-size options this * field should be set to zero. */ uint64_t nro_size; }; /* Header common to all requests. Do not reorder these fields, as we need * the second one (nr_reqtype) to know how much to copy from/to userspace. */ struct nmreq_header { uint16_t nr_version; /* API version */ uint16_t nr_reqtype; /* nmreq type (NETMAP_REQ_*) */ uint32_t nr_reserved; /* must be zero */ #define NETMAP_REQ_IFNAMSIZ 64 char nr_name[NETMAP_REQ_IFNAMSIZ]; /* port name */ uint64_t nr_options; /* command-specific options */ uint64_t nr_body; /* ptr to nmreq_xyz struct */ }; enum { /* Register a netmap port with the device. */ NETMAP_REQ_REGISTER = 1, /* Get information from a netmap port. */ NETMAP_REQ_PORT_INFO_GET, /* Attach a netmap port to a VALE switch. */ NETMAP_REQ_VALE_ATTACH, /* Detach a netmap port from a VALE switch. */ NETMAP_REQ_VALE_DETACH, /* List the ports attached to a VALE switch. */ NETMAP_REQ_VALE_LIST, /* Set the port header length (was virtio-net header length). */ NETMAP_REQ_PORT_HDR_SET, /* Get the port header length (was virtio-net header length). */ NETMAP_REQ_PORT_HDR_GET, /* Create a new persistent VALE port. */ NETMAP_REQ_VALE_NEWIF, /* Delete a persistent VALE port. */ NETMAP_REQ_VALE_DELIF, /* Enable polling kernel thread(s) on an attached VALE port. */ NETMAP_REQ_VALE_POLLING_ENABLE, /* Disable polling kernel thread(s) on an attached VALE port. */ NETMAP_REQ_VALE_POLLING_DISABLE, /* Get info about the pools of a memory allocator. */ NETMAP_REQ_POOLS_INFO_GET, /* Start an in-kernel loop that syncs the rings periodically or * on notifications. The loop runs in the context of the ioctl * syscall, and only stops on NETMAP_REQ_SYNC_KLOOP_STOP. */ NETMAP_REQ_SYNC_KLOOP_START, /* Stops the thread executing the in-kernel loop. The thread * returns from the ioctl syscall. */ NETMAP_REQ_SYNC_KLOOP_STOP, /* Enable CSB mode on a registered netmap control device. */ NETMAP_REQ_CSB_ENABLE, }; enum { /* On NETMAP_REQ_REGISTER, ask netmap to use memory allocated * from user-space allocated memory pools (e.g. hugepages). */ NETMAP_REQ_OPT_EXTMEM = 1, /* ON NETMAP_REQ_SYNC_KLOOP_START, ask netmap to use eventfd-based * notifications to synchronize the kernel loop with the application. */ NETMAP_REQ_OPT_SYNC_KLOOP_EVENTFDS, /* On NETMAP_REQ_REGISTER, ask netmap to work in CSB mode, where * head, cur and tail pointers are not exchanged through the * struct netmap_ring header, but rather using an user-provided * memory area (see struct nm_csb_atok and struct nm_csb_ktoa). */ NETMAP_REQ_OPT_CSB, /* An extension to NETMAP_REQ_OPT_SYNC_KLOOP_EVENTFDS, which specifies * if the TX and/or RX rings are synced in the context of the VM exit. * This requires the 'ioeventfd' fields to be valid (cannot be < 0). */ NETMAP_REQ_OPT_SYNC_KLOOP_MODE, /* On NETMAP_REQ_REGISTER, ask for (part of) the ptr field in the * slots of the registered rings to be used as an offset field * for the start of the packets inside the netmap buffer. */ NETMAP_REQ_OPT_OFFSETS, /* This is a marker to count the number of available options. * New options must be added above it. */ NETMAP_REQ_OPT_MAX, }; /* * nr_reqtype: NETMAP_REQ_REGISTER * Bind (register) a netmap port to this control device. */ struct nmreq_register { uint64_t nr_offset; /* nifp offset in the shared region */ uint64_t nr_memsize; /* size of the shared region */ uint32_t nr_tx_slots; /* slots in tx rings */ uint32_t nr_rx_slots; /* slots in rx rings */ uint16_t nr_tx_rings; /* number of tx rings */ uint16_t nr_rx_rings; /* number of rx rings */ uint16_t nr_host_tx_rings; /* number of host tx rings */ uint16_t nr_host_rx_rings; /* number of host rx rings */ uint16_t nr_mem_id; /* id of the memory allocator */ uint16_t nr_ringid; /* ring(s) we care about */ uint32_t nr_mode; /* specify NR_REG_* modes */ uint32_t nr_extra_bufs; /* number of requested extra buffers */ uint64_t nr_flags; /* additional flags (see below) */ /* monitors use nr_ringid and nr_mode to select the rings to monitor */ #define NR_MONITOR_TX 0x100 #define NR_MONITOR_RX 0x200 #define NR_ZCOPY_MON 0x400 /* request exclusive access to the selected rings */ #define NR_EXCLUSIVE 0x800 /* 0x1000 unused */ #define NR_RX_RINGS_ONLY 0x2000 #define NR_TX_RINGS_ONLY 0x4000 /* Applications set this flag if they are able to deal with virtio-net headers, * that is send/receive frames that start with a virtio-net header. * If not set, NETMAP_REQ_REGISTER will fail with netmap ports that require * applications to use those headers. If the flag is set, the application can * use the NETMAP_VNET_HDR_GET command to figure out the header length. */ #define NR_ACCEPT_VNET_HDR 0x8000 /* The following two have the same meaning of NETMAP_NO_TX_POLL and * NETMAP_DO_RX_POLL. */ #define NR_DO_RX_POLL 0x10000 #define NR_NO_TX_POLL 0x20000 }; /* Valid values for nmreq_register.nr_mode (see above). */ enum { NR_REG_DEFAULT = 0, /* backward compat, should not be used. */ NR_REG_ALL_NIC = 1, NR_REG_SW = 2, NR_REG_NIC_SW = 3, NR_REG_ONE_NIC = 4, NR_REG_PIPE_MASTER = 5, /* deprecated, use "x{y" port name syntax */ NR_REG_PIPE_SLAVE = 6, /* deprecated, use "x}y" port name syntax */ NR_REG_NULL = 7, NR_REG_ONE_SW = 8, }; /* A single ioctl number is shared by all the new API command. * Demultiplexing is done using the hdr.nr_reqtype field. * FreeBSD uses the size value embedded in the _IOWR to determine * how much to copy in/out, so we define the ioctl() command * specifying only nmreq_header, and copyin/copyout the rest. */ #define NIOCCTRL _IOWR('i', 151, struct nmreq_header) /* The ioctl commands to sync TX/RX netmap rings. * NIOCTXSYNC, NIOCRXSYNC synchronize tx or rx queues, * whose identity is set in NETMAP_REQ_REGISTER through nr_ringid. * These are non blocking and take no argument. */ #define NIOCTXSYNC _IO('i', 148) /* sync tx queues */ #define NIOCRXSYNC _IO('i', 149) /* sync rx queues */ /* * nr_reqtype: NETMAP_REQ_PORT_INFO_GET * Get information about a netmap port, including number of rings. * slots per ring, id of the memory allocator, etc. The netmap * control device used for this operation does not need to be bound * to a netmap port. */ struct nmreq_port_info_get { uint64_t nr_memsize; /* size of the shared region */ uint32_t nr_tx_slots; /* slots in tx rings */ uint32_t nr_rx_slots; /* slots in rx rings */ uint16_t nr_tx_rings; /* number of tx rings */ uint16_t nr_rx_rings; /* number of rx rings */ uint16_t nr_host_tx_rings; /* number of host tx rings */ uint16_t nr_host_rx_rings; /* number of host rx rings */ uint16_t nr_mem_id; /* memory allocator id (in/out) */ uint16_t pad[3]; }; #define NM_BDG_NAME "vale" /* prefix for bridge port name */ /* * nr_reqtype: NETMAP_REQ_VALE_ATTACH * Attach a netmap port to a VALE switch. Both the name of the netmap * port and the VALE switch are specified through the nr_name argument. * The attach operation could need to register a port, so at least * the same arguments are available. * port_index will contain the index where the port has been attached. */ struct nmreq_vale_attach { struct nmreq_register reg; uint32_t port_index; uint32_t pad1; }; /* * nr_reqtype: NETMAP_REQ_VALE_DETACH * Detach a netmap port from a VALE switch. Both the name of the netmap * port and the VALE switch are specified through the nr_name argument. * port_index will contain the index where the port was attached. */ struct nmreq_vale_detach { uint32_t port_index; uint32_t pad1; }; /* * nr_reqtype: NETMAP_REQ_VALE_LIST * List the ports of a VALE switch. */ struct nmreq_vale_list { /* Name of the VALE port (valeXXX:YYY) or empty. */ uint16_t nr_bridge_idx; uint16_t pad1; uint32_t nr_port_idx; }; /* * nr_reqtype: NETMAP_REQ_PORT_HDR_SET or NETMAP_REQ_PORT_HDR_GET * Set or get the port header length of the port identified by hdr.nr_name. * The control device does not need to be bound to a netmap port. */ struct nmreq_port_hdr { uint32_t nr_hdr_len; uint32_t pad1; }; /* * nr_reqtype: NETMAP_REQ_VALE_NEWIF * Create a new persistent VALE port. */ struct nmreq_vale_newif { uint32_t nr_tx_slots; /* slots in tx rings */ uint32_t nr_rx_slots; /* slots in rx rings */ uint16_t nr_tx_rings; /* number of tx rings */ uint16_t nr_rx_rings; /* number of rx rings */ uint16_t nr_mem_id; /* id of the memory allocator */ uint16_t pad1; }; /* * nr_reqtype: NETMAP_REQ_VALE_POLLING_ENABLE or NETMAP_REQ_VALE_POLLING_DISABLE * Enable or disable polling kthreads on a VALE port. */ struct nmreq_vale_polling { uint32_t nr_mode; #define NETMAP_POLLING_MODE_SINGLE_CPU 1 #define NETMAP_POLLING_MODE_MULTI_CPU 2 uint32_t nr_first_cpu_id; uint32_t nr_num_polling_cpus; uint32_t pad1; }; /* * nr_reqtype: NETMAP_REQ_POOLS_INFO_GET * Get info about the pools of the memory allocator of the netmap * port specified by hdr.nr_name and nr_mem_id. The netmap control * device used for this operation does not need to be bound to a netmap * port. */ struct nmreq_pools_info { uint64_t nr_memsize; uint16_t nr_mem_id; /* in/out argument */ uint16_t pad1[3]; uint64_t nr_if_pool_offset; uint32_t nr_if_pool_objtotal; uint32_t nr_if_pool_objsize; uint64_t nr_ring_pool_offset; uint32_t nr_ring_pool_objtotal; uint32_t nr_ring_pool_objsize; uint64_t nr_buf_pool_offset; uint32_t nr_buf_pool_objtotal; uint32_t nr_buf_pool_objsize; }; /* * nr_reqtype: NETMAP_REQ_SYNC_KLOOP_START * Start an in-kernel loop that syncs the rings periodically or on * notifications. The loop runs in the context of the ioctl syscall, * and only stops on NETMAP_REQ_SYNC_KLOOP_STOP. * The registered netmap port must be open in CSB mode. */ struct nmreq_sync_kloop_start { /* Sleeping is the default synchronization method for the kloop. * The 'sleep_us' field specifies how many microseconds to sleep for * when there is no work to do, before doing another kloop iteration. */ uint32_t sleep_us; uint32_t pad1; }; /* A CSB entry for the application --> kernel direction. */ struct nm_csb_atok { uint32_t head; /* AW+ KR+ the head of the appl netmap_ring */ uint32_t cur; /* AW+ KR+ the cur of the appl netmap_ring */ uint32_t appl_need_kick; /* AW+ KR+ kern --> appl notification enable */ uint32_t sync_flags; /* AW+ KR+ the flags of the appl [tx|rx]sync() */ uint32_t pad[12]; /* pad to a 64 bytes cacheline */ }; /* A CSB entry for the application <-- kernel direction. */ struct nm_csb_ktoa { uint32_t hwcur; /* AR+ KW+ the hwcur of the kern netmap_kring */ uint32_t hwtail; /* AR+ KW+ the hwtail of the kern netmap_kring */ uint32_t kern_need_kick; /* AR+ KW+ appl-->kern notification enable */ uint32_t pad[13]; }; #ifdef __linux__ #ifdef __KERNEL__ #define nm_stst_barrier smp_wmb #define nm_ldld_barrier smp_rmb #define nm_stld_barrier smp_mb #else /* !__KERNEL__ */ static inline void nm_stst_barrier(void) { /* A memory barrier with release semantic has the combined * effect of a store-store barrier and a load-store barrier, * which is fine for us. */ __atomic_thread_fence(__ATOMIC_RELEASE); } static inline void nm_ldld_barrier(void) { /* A memory barrier with acquire semantic has the combined * effect of a load-load barrier and a store-load barrier, * which is fine for us. */ __atomic_thread_fence(__ATOMIC_ACQUIRE); } #endif /* !__KERNEL__ */ #elif defined(__FreeBSD__) #ifdef _KERNEL #define nm_stst_barrier atomic_thread_fence_rel #define nm_ldld_barrier atomic_thread_fence_acq #define nm_stld_barrier atomic_thread_fence_seq_cst #else /* !_KERNEL */ #ifdef __cplusplus #include <atomic> using std::memory_order_release; using std::memory_order_acquire; #else /* __cplusplus */ #include <stdatomic.h> #endif /* __cplusplus */ static inline void nm_stst_barrier(void) { atomic_thread_fence(memory_order_release); } static inline void nm_ldld_barrier(void) { atomic_thread_fence(memory_order_acquire); } #endif /* !_KERNEL */ #else /* !__linux__ && !__FreeBSD__ */ #error "OS not supported" #endif /* !__linux__ && !__FreeBSD__ */ /* Application side of sync-kloop: Write ring pointers (cur, head) to the CSB. * This routine is coupled with sync_kloop_kernel_read(). */ static inline void nm_sync_kloop_appl_write(struct nm_csb_atok *atok, uint32_t cur, uint32_t head) { /* Issue a first store-store barrier to make sure writes to the * netmap ring do not overcome updates on atok->cur and atok->head. */ nm_stst_barrier(); /* * We need to write cur and head to the CSB but we cannot do it atomically. * There is no way we can prevent the host from reading the updated value * of one of the two and the old value of the other. However, if we make * sure that the host never reads a value of head more recent than the * value of cur we are safe. We can allow the host to read a value of cur * more recent than the value of head, since in the netmap ring cur can be * ahead of head and cur cannot wrap around head because it must be behind * tail. Inverting the order of writes below could instead result into the * host to think head went ahead of cur, which would cause the sync * prologue to fail. * * The following memory barrier scheme is used to make this happen: * * Guest Host * * STORE(cur) LOAD(head) * wmb() <-----------> rmb() * STORE(head) LOAD(cur) * */ atok->cur = cur; nm_stst_barrier(); atok->head = head; } /* Application side of sync-kloop: Read kring pointers (hwcur, hwtail) from * the CSB. This routine is coupled with sync_kloop_kernel_write(). */ static inline void nm_sync_kloop_appl_read(struct nm_csb_ktoa *ktoa, uint32_t *hwtail, uint32_t *hwcur) { /* * We place a memory barrier to make sure that the update of hwtail never * overtakes the update of hwcur. * (see explanation in sync_kloop_kernel_write). */ *hwtail = ktoa->hwtail; nm_ldld_barrier(); *hwcur = ktoa->hwcur; /* Make sure that loads from ktoa->hwtail and ktoa->hwcur are not delayed * after the loads from the netmap ring. */ nm_ldld_barrier(); } /* * data for NETMAP_REQ_OPT_* options */ struct nmreq_opt_sync_kloop_eventfds { struct nmreq_option nro_opt; /* common header */ /* An array of N entries for bidirectional notifications between * the kernel loop and the application. The number of entries and * their order must agree with the CSB arrays passed in the * NETMAP_REQ_OPT_CSB option. Each entry contains a file descriptor * backed by an eventfd. * * If any of the 'ioeventfd' entries is < 0, the event loop uses * the sleeping synchronization strategy (according to sleep_us), * and keeps kern_need_kick always disabled. * Each 'irqfd' can be < 0, and in that case the corresponding queue * is never notified. */ struct { /* Notifier for the application --> kernel loop direction. */ int32_t ioeventfd; /* Notifier for the kernel loop --> application direction. */ int32_t irqfd; } eventfds[0]; }; struct nmreq_opt_sync_kloop_mode { struct nmreq_option nro_opt; /* common header */ #define NM_OPT_SYNC_KLOOP_DIRECT_TX (1 << 0) #define NM_OPT_SYNC_KLOOP_DIRECT_RX (1 << 1) uint32_t mode; }; struct nmreq_opt_extmem { struct nmreq_option nro_opt; /* common header */ uint64_t nro_usrptr; /* (in) ptr to usr memory */ struct nmreq_pools_info nro_info; /* (in/out) */ }; struct nmreq_opt_csb { struct nmreq_option nro_opt; /* Array of CSB entries for application --> kernel communication * (N entries). */ uint64_t csb_atok; /* Array of CSB entries for kernel --> application communication * (N entries). */ uint64_t csb_ktoa; }; /* option NETMAP_REQ_OPT_OFFSETS */ struct nmreq_opt_offsets { struct nmreq_option nro_opt; /* the user must declare the maximum offset value that she is * going to put into the offset slot-fields. Any larger value * found at runtime will be cropped. On output the (possibly * higher) effective max value is returned. */ uint64_t nro_max_offset; /* optional initial offset value, to be set in all slots. */ uint64_t nro_initial_offset; /* number of bits in the lower part of the 'ptr' field to be * used as the offset field. On output the (possibly larger) * effective number of bits is returned. * 0 means: use the whole ptr field. */ uint32_t nro_offset_bits; /* required alignment for the beginning of the packets * (base of the buffer plus offset) in the TX slots. */ uint32_t nro_tx_align; /* Reserved: set to zero. */ uint64_t nro_min_gap; }; #endif /* _NET_NETMAP_H_ */
