netmap_kern.h revision 231594
1/* 2 * Copyright (C) 2011-2012 Matteo Landi, Luigi Rizzo. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 */ 25 26/* 27 * $FreeBSD: head/sys/dev/netmap/netmap_kern.h 231594 2012-02-13 18:56:34Z luigi $ 28 * $Id: netmap_kern.h 9795 2011-12-02 11:39:08Z luigi $ 29 * 30 * The header contains the definitions of constants and function 31 * prototypes used only in kernelspace. 32 */ 33 34#ifndef _NET_NETMAP_KERN_H_ 35#define _NET_NETMAP_KERN_H_ 36 37#if defined(__FreeBSD__) 38#define NM_LOCK_T struct mtx 39#define NM_SELINFO_T struct selinfo 40#define MBUF_LEN(m) ((m)->m_pkthdr.len) 41#define NM_SEND_UP(ifp, m) ((ifp)->if_input)(ifp, m) 42#elif defined (__linux__) 43#define NM_LOCK_T spinlock_t 44#define NM_SELINFO_T wait_queue_head_t 45#define MBUF_LEN(m) ((m)->len) 46#define NM_SEND_UP(ifp, m) netif_rx(m) 47#else 48#error unsupported platform 49#endif 50 51#ifdef MALLOC_DECLARE 52MALLOC_DECLARE(M_NETMAP); 53#endif 54 55#define ND(format, ...) 56#define D(format, ...) \ 57 do { \ 58 struct timeval __xxts; \ 59 microtime(&__xxts); \ 60 printf("%03d.%06d %s [%d] " format "\n", \ 61 (int)__xxts.tv_sec % 1000, (int)__xxts.tv_usec, \ 62 __FUNCTION__, __LINE__, ##__VA_ARGS__); \ 63 } while (0) 64 65struct netmap_adapter; 66 67/* 68 * private, kernel view of a ring. 69 * 70 * The indexes in the NIC and netmap rings are offset by nkr_hwofs slots. 71 * This is so that, on a reset, buffers owned by userspace are not 72 * modified by the kernel. In particular: 73 * RX rings: the next empty buffer (hwcur + hwavail + hwofs) coincides with 74 * the next empty buffer as known by the hardware (next_to_check or so). 75 * TX rings: hwcur + hwofs coincides with next_to_send 76 */ 77struct netmap_kring { 78 struct netmap_ring *ring; 79 u_int nr_hwcur; 80 int nr_hwavail; 81 u_int nr_kflags; /* private driver flags */ 82#define NKR_PENDINTR 0x1 // Pending interrupt. 83 u_int nkr_num_slots; 84 85 int nkr_hwofs; /* offset between NIC and netmap ring */ 86 struct netmap_adapter *na; 87 NM_SELINFO_T si; /* poll/select wait queue */ 88 NM_LOCK_T q_lock; /* used if no device lock available */ 89} __attribute__((__aligned__(64))); 90 91/* 92 * This struct extends the 'struct adapter' (or 93 * equivalent) device descriptor. It contains all fields needed to 94 * support netmap operation. 95 */ 96struct netmap_adapter { 97 int refcount; /* number of user-space descriptors using this 98 interface, which is equal to the number of 99 struct netmap_if objs in the mapped region. */ 100 101 int separate_locks; /* set if the interface suports different 102 locks for rx, tx and core. */ 103 104 u_int num_queues; /* number of tx/rx queue pairs: this is 105 a duplicate field needed to simplify the 106 signature of ``netmap_detach``. */ 107 108 u_int num_tx_desc; /* number of descriptor in each queue */ 109 u_int num_rx_desc; 110 u_int buff_size; 111 112 //u_int flags; // XXX unused 113 /* tx_rings and rx_rings are private but allocated 114 * as a contiguous chunk of memory. Each array has 115 * N+1 entries, for the adapter queues and for the host queue. 116 */ 117 struct netmap_kring *tx_rings; /* array of TX rings. */ 118 struct netmap_kring *rx_rings; /* array of RX rings. */ 119 120 /* copy of if_qflush and if_transmit pointers, to intercept 121 * packets from the network stack when netmap is active. 122 * XXX probably if_qflush is not necessary. 123 */ 124 //void (*if_qflush)(struct ifnet *); // XXX unused 125 int (*if_transmit)(struct ifnet *, struct mbuf *); 126 127 /* references to the ifnet and device routines, used by 128 * the generic netmap functions. 129 */ 130 struct ifnet *ifp; /* adapter is ifp->if_softc */ 131 132 NM_LOCK_T core_lock; /* used if no device lock available */ 133 134 int (*nm_register)(struct ifnet *, int onoff); 135 void (*nm_lock)(struct ifnet *, int what, u_int ringid); 136 int (*nm_txsync)(struct ifnet *, u_int ring, int lock); 137 int (*nm_rxsync)(struct ifnet *, u_int ring, int lock); 138}; 139 140/* 141 * The combination of "enable" (ifp->if_capabilities &IFCAP_NETMAP) 142 * and refcount gives the status of the interface, namely: 143 * 144 * enable refcount Status 145 * 146 * FALSE 0 normal operation 147 * FALSE != 0 -- (impossible) 148 * TRUE 1 netmap mode 149 * TRUE 0 being deleted. 150 */ 151 152#define NETMAP_DELETING(_na) ( ((_na)->refcount == 0) && \ 153 ( (_na)->ifp->if_capenable & IFCAP_NETMAP) ) 154 155/* 156 * parameters for (*nm_lock)(adapter, what, index) 157 */ 158enum { 159 NETMAP_NO_LOCK = 0, 160 NETMAP_CORE_LOCK, NETMAP_CORE_UNLOCK, 161 NETMAP_TX_LOCK, NETMAP_TX_UNLOCK, 162 NETMAP_RX_LOCK, NETMAP_RX_UNLOCK, 163#ifdef __FreeBSD__ 164#define NETMAP_REG_LOCK NETMAP_CORE_LOCK 165#define NETMAP_REG_UNLOCK NETMAP_CORE_UNLOCK 166#else 167 NETMAP_REG_LOCK, NETMAP_REG_UNLOCK 168#endif 169}; 170 171/* 172 * The following are support routines used by individual drivers to 173 * support netmap operation. 174 * 175 * netmap_attach() initializes a struct netmap_adapter, allocating the 176 * struct netmap_ring's and the struct selinfo. 177 * 178 * netmap_detach() frees the memory allocated by netmap_attach(). 179 * 180 * netmap_start() replaces the if_transmit routine of the interface, 181 * and is used to intercept packets coming from the stack. 182 * 183 * netmap_load_map/netmap_reload_map are helper routines to set/reset 184 * the dmamap for a packet buffer 185 * 186 * netmap_reset() is a helper routine to be called in the driver 187 * when reinitializing a ring. 188 */ 189int netmap_attach(struct netmap_adapter *, int); 190void netmap_detach(struct ifnet *); 191int netmap_start(struct ifnet *, struct mbuf *); 192enum txrx { NR_RX = 0, NR_TX = 1 }; 193struct netmap_slot *netmap_reset(struct netmap_adapter *na, 194 enum txrx tx, int n, u_int new_cur); 195int netmap_ring_reinit(struct netmap_kring *); 196 197extern int netmap_buf_size; 198#define NETMAP_BUF_SIZE netmap_buf_size 199extern int netmap_mitigate; 200extern int netmap_no_pendintr; 201extern u_int netmap_total_buffers; 202extern char *netmap_buffer_base; 203extern int netmap_verbose; // XXX debugging 204enum { /* verbose flags */ 205 NM_VERB_ON = 1, /* generic verbose */ 206 NM_VERB_HOST = 0x2, /* verbose host stack */ 207 NM_VERB_RXSYNC = 0x10, /* verbose on rxsync/txsync */ 208 NM_VERB_TXSYNC = 0x20, 209 NM_VERB_RXINTR = 0x100, /* verbose on rx/tx intr (driver) */ 210 NM_VERB_TXINTR = 0x200, 211 NM_VERB_NIC_RXSYNC = 0x1000, /* verbose on rx/tx intr (driver) */ 212 NM_VERB_NIC_TXSYNC = 0x2000, 213}; 214 215/* 216 * NA returns a pointer to the struct netmap adapter from the ifp, 217 * WNA is used to write it. 218 */ 219#ifndef WNA 220#define WNA(_ifp) (_ifp)->if_pspare[0] 221#endif 222#define NA(_ifp) ((struct netmap_adapter *)WNA(_ifp)) 223 224 225/* Callback invoked by the dma machinery after a successfull dmamap_load */ 226static void netmap_dmamap_cb(__unused void *arg, 227 __unused bus_dma_segment_t * segs, __unused int nseg, __unused int error) 228{ 229} 230 231/* bus_dmamap_load wrapper: call aforementioned function if map != NULL. 232 * XXX can we do it without a callback ? 233 */ 234static inline void 235netmap_load_map(bus_dma_tag_t tag, bus_dmamap_t map, void *buf) 236{ 237 if (map) 238 bus_dmamap_load(tag, map, buf, NETMAP_BUF_SIZE, 239 netmap_dmamap_cb, NULL, BUS_DMA_NOWAIT); 240} 241 242/* update the map when a buffer changes. */ 243static inline void 244netmap_reload_map(bus_dma_tag_t tag, bus_dmamap_t map, void *buf) 245{ 246 if (map) { 247 bus_dmamap_unload(tag, map); 248 bus_dmamap_load(tag, map, buf, NETMAP_BUF_SIZE, 249 netmap_dmamap_cb, NULL, BUS_DMA_NOWAIT); 250 } 251} 252 253 254/* 255 * NMB return the virtual address of a buffer (buffer 0 on bad index) 256 * PNMB also fills the physical address 257 */ 258static inline void * 259NMB(struct netmap_slot *slot) 260{ 261 uint32_t i = slot->buf_idx; 262 return (i >= netmap_total_buffers) ? netmap_buffer_base : 263 netmap_buffer_base + (i *NETMAP_BUF_SIZE); 264} 265 266static inline void * 267PNMB(struct netmap_slot *slot, uint64_t *pp) 268{ 269 uint32_t i = slot->buf_idx; 270 void *ret = (i >= netmap_total_buffers) ? netmap_buffer_base : 271 netmap_buffer_base + (i *NETMAP_BUF_SIZE); 272 *pp = vtophys(ret); 273 return ret; 274} 275 276/* default functions to handle rx/tx interrupts */ 277int netmap_rx_irq(struct ifnet *, int, int *); 278#define netmap_tx_irq(_n, _q) netmap_rx_irq(_n, _q, NULL) 279#ifdef __linux__ 280#define bus_dmamap_sync(_a, _b, _c) // wmb() or rmb() ? 281netdev_tx_t netmap_start_linux(struct sk_buff *skb, struct net_device *dev); 282#endif 283#endif /* _NET_NETMAP_KERN_H_ */ 284