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 * $FreeBSD$ 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 52 MALLOC_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 65 struct 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 */ 77 struct 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 */ 96 struct 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 */ 158 enum { 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 */ 189 int netmap_attach(struct netmap_adapter *, int); 190 void netmap_detach(struct ifnet *); 191 int netmap_start(struct ifnet *, struct mbuf *); 192 enum txrx { NR_RX = 0, NR_TX = 1 }; 193 struct netmap_slot *netmap_reset(struct netmap_adapter *na, 194 enum txrx tx, int n, u_int new_cur); 195 int netmap_ring_reinit(struct netmap_kring *); 196 197 extern int netmap_buf_size; 198 #define NETMAP_BUF_SIZE netmap_buf_size 199 extern int netmap_mitigate; 200 extern int netmap_no_pendintr; 201 extern u_int netmap_total_buffers; 202 extern char *netmap_buffer_base; 203 extern int netmap_verbose; // XXX debugging 204 enum { /* 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 */ 226 static 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 */ 234 static inline void 235 netmap_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. */ 243 static inline void 244 netmap_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 * functions to map NIC to KRING indexes (n2k) and vice versa (k2n) 255 */ 256 static inline int 257 netmap_ridx_n2k(struct netmap_adapter *na, int ring, int nic_idx) 258 { 259 int kring_idx = nic_idx + na->rx_rings[ring].nkr_hwofs; 260 if (kring_idx < 0) 261 return kring_idx + na->num_rx_desc; 262 else if (kring_idx < na->num_rx_desc) 263 return kring_idx; 264 else 265 return kring_idx - na->num_rx_desc; 266 } 267 268 static inline int 269 netmap_tidx_n2k(struct netmap_adapter *na, int ring, int nic_idx) 270 { 271 int kring_idx = nic_idx + na->tx_rings[ring].nkr_hwofs; 272 if (kring_idx < 0) 273 return kring_idx + na->num_tx_desc; 274 else if (kring_idx < na->num_tx_desc) 275 return kring_idx; 276 else 277 return kring_idx - na->num_tx_desc; 278 } 279 280 281 static inline int 282 netmap_ridx_k2n(struct netmap_adapter *na, int ring, int kring_idx) 283 { 284 int nic_idx = kring_idx - na->rx_rings[ring].nkr_hwofs; 285 if (nic_idx < 0) 286 return nic_idx + na->num_rx_desc; 287 else if (nic_idx < na->num_rx_desc) 288 return nic_idx; 289 else 290 return nic_idx - na->num_rx_desc; 291 } 292 293 294 static inline int 295 netmap_tidx_k2n(struct netmap_adapter *na, int ring, int kring_idx) 296 { 297 int nic_idx = kring_idx - na->tx_rings[ring].nkr_hwofs; 298 if (nic_idx < 0) 299 return nic_idx + na->num_tx_desc; 300 else if (nic_idx < na->num_tx_desc) 301 return nic_idx; 302 else 303 return nic_idx - na->num_tx_desc; 304 } 305 306 /* 307 * NMB return the virtual address of a buffer (buffer 0 on bad index) 308 * PNMB also fills the physical address 309 */ 310 static inline void * 311 NMB(struct netmap_slot *slot) 312 { 313 uint32_t i = slot->buf_idx; 314 return (i >= netmap_total_buffers) ? netmap_buffer_base : 315 netmap_buffer_base + (i *NETMAP_BUF_SIZE); 316 } 317 318 static inline void * 319 PNMB(struct netmap_slot *slot, uint64_t *pp) 320 { 321 uint32_t i = slot->buf_idx; 322 void *ret = (i >= netmap_total_buffers) ? netmap_buffer_base : 323 netmap_buffer_base + (i *NETMAP_BUF_SIZE); 324 *pp = vtophys(ret); 325 return ret; 326 } 327 328 /* default functions to handle rx/tx interrupts */ 329 int netmap_rx_irq(struct ifnet *, int, int *); 330 #define netmap_tx_irq(_n, _q) netmap_rx_irq(_n, _q, NULL) 331 #ifdef __linux__ 332 #define bus_dmamap_sync(_a, _b, _c) // wmb() or rmb() ? 333 netdev_tx_t netmap_start_linux(struct sk_buff *skb, struct net_device *dev); 334 #endif 335 #endif /* _NET_NETMAP_KERN_H_ */ 336