xref: /freebsd/sys/dev/netmap/if_re_netmap.h (revision f05cddf9) 
1 /*
2  * Copyright (C) 2011 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  *
29  * netmap support for "re"
30  * For details on netmap support please see ixgbe_netmap.h
31  */
32 
33 
34 #include <net/netmap.h>
35 #include <sys/selinfo.h>
36 #include <vm/vm.h>
37 #include <vm/pmap.h>    /* vtophys ? */
38 #include <dev/netmap/netmap_kern.h>
39 
40 
41 /*
42  * wrapper to export locks to the generic code
43  * We should not use the tx/rx locks
44  */
45 static void
46 re_netmap_lock_wrapper(struct ifnet *ifp, int what, u_int queueid)
47 {
48 	struct rl_softc *adapter = ifp->if_softc;
49 
50 	switch (what) {
51 	case NETMAP_CORE_LOCK:
52 		RL_LOCK(adapter);
53 		break;
54 	case NETMAP_CORE_UNLOCK:
55 		RL_UNLOCK(adapter);
56 		break;
57 
58 	case NETMAP_TX_LOCK:
59 	case NETMAP_RX_LOCK:
60 	case NETMAP_TX_UNLOCK:
61 	case NETMAP_RX_UNLOCK:
62 		D("invalid lock call %d, no tx/rx locks here", what);
63 		break;
64 	}
65 }
66 
67 
68 /*
69  * support for netmap register/unregisted. We are already under core lock.
70  * only called on the first register or the last unregister.
71  */
72 static int
73 re_netmap_reg(struct ifnet *ifp, int onoff)
74 {
75 	struct rl_softc *adapter = ifp->if_softc;
76 	struct netmap_adapter *na = NA(ifp);
77 	int error = 0;
78 
79 	if (na == NULL)
80 		return EINVAL;
81 	/* Tell the stack that the interface is no longer active */
82 	ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
83 
84 	re_stop(adapter);
85 
86 	if (onoff) {
87 		ifp->if_capenable |= IFCAP_NETMAP;
88 
89 		/* save if_transmit to restore it later */
90 		na->if_transmit = ifp->if_transmit;
91 		ifp->if_transmit = netmap_start;
92 
93 		re_init_locked(adapter);
94 
95 		if ((ifp->if_drv_flags & (IFF_DRV_RUNNING | IFF_DRV_OACTIVE)) == 0) {
96 			error = ENOMEM;
97 			goto fail;
98 		}
99 	} else {
100 fail:
101 		/* restore if_transmit */
102 		ifp->if_transmit = na->if_transmit;
103 		ifp->if_capenable &= ~IFCAP_NETMAP;
104 		re_init_locked(adapter);	/* also enables intr */
105 	}
106 	return (error);
107 }
108 
109 
110 /*
111  * Reconcile kernel and user view of the transmit ring.
112  */
113 static int
114 re_netmap_txsync(struct ifnet *ifp, u_int ring_nr, int do_lock)
115 {
116 	struct rl_softc *sc = ifp->if_softc;
117 	struct rl_txdesc *txd = sc->rl_ldata.rl_tx_desc;
118 	struct netmap_adapter *na = NA(sc->rl_ifp);
119 	struct netmap_kring *kring = &na->tx_rings[ring_nr];
120 	struct netmap_ring *ring = kring->ring;
121 	int j, k, l, n, lim = kring->nkr_num_slots - 1;
122 
123 	k = ring->cur;
124 	if (k > lim)
125 		return netmap_ring_reinit(kring);
126 
127 	if (do_lock)
128 		RL_LOCK(sc);
129 
130 	/* Sync the TX descriptor list */
131 	bus_dmamap_sync(sc->rl_ldata.rl_tx_list_tag,
132             sc->rl_ldata.rl_tx_list_map,
133             BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
134 
135 	/* XXX move after the transmissions */
136 	/* record completed transmissions */
137         for (n = 0, l = sc->rl_ldata.rl_tx_considx;
138 	    l != sc->rl_ldata.rl_tx_prodidx;
139 	    n++, l = RL_TX_DESC_NXT(sc, l)) {
140 		uint32_t cmdstat =
141 			le32toh(sc->rl_ldata.rl_tx_list[l].rl_cmdstat);
142 		if (cmdstat & RL_TDESC_STAT_OWN)
143 			break;
144 	}
145 	if (n > 0) {
146 		sc->rl_ldata.rl_tx_considx = l;
147 		sc->rl_ldata.rl_tx_free += n;
148 		kring->nr_hwavail += n;
149 	}
150 
151 	/* update avail to what the kernel knows */
152 	ring->avail = kring->nr_hwavail;
153 
154 	j = kring->nr_hwcur;
155 	if (j != k) {	/* we have new packets to send */
156 		l = sc->rl_ldata.rl_tx_prodidx;
157 		for (n = 0; j != k; n++) {
158 			struct netmap_slot *slot = &ring->slot[j];
159 			struct rl_desc *desc = &sc->rl_ldata.rl_tx_list[l];
160 			int cmd = slot->len | RL_TDESC_CMD_EOF |
161 				RL_TDESC_CMD_OWN | RL_TDESC_CMD_SOF ;
162 			uint64_t paddr;
163 			void *addr = PNMB(slot, &paddr);
164 			int len = slot->len;
165 
166 			if (addr == netmap_buffer_base || len > NETMAP_BUF_SIZE) {
167 				if (do_lock)
168 					RL_UNLOCK(sc);
169 				// XXX what about prodidx ?
170 				return netmap_ring_reinit(kring);
171 			}
172 
173 			if (l == lim)	/* mark end of ring */
174 				cmd |= RL_TDESC_CMD_EOR;
175 
176 			if (slot->flags & NS_BUF_CHANGED) {
177 				desc->rl_bufaddr_lo = htole32(RL_ADDR_LO(paddr));
178 				desc->rl_bufaddr_hi = htole32(RL_ADDR_HI(paddr));
179 				/* buffer has changed, unload and reload map */
180 				netmap_reload_map(sc->rl_ldata.rl_tx_mtag,
181 					txd[l].tx_dmamap, addr);
182 				slot->flags &= ~NS_BUF_CHANGED;
183 			}
184 			slot->flags &= ~NS_REPORT;
185 			desc->rl_cmdstat = htole32(cmd);
186 			bus_dmamap_sync(sc->rl_ldata.rl_tx_mtag,
187 				txd[l].tx_dmamap, BUS_DMASYNC_PREWRITE);
188 			j = (j == lim) ? 0 : j + 1;
189 			l = (l == lim) ? 0 : l + 1;
190 		}
191 		sc->rl_ldata.rl_tx_prodidx = l;
192 		kring->nr_hwcur = k; /* the saved ring->cur */
193 		ring->avail -= n; // XXX see others
194 		kring->nr_hwavail = ring->avail;
195 
196 		bus_dmamap_sync(sc->rl_ldata.rl_tx_list_tag,
197 		    sc->rl_ldata.rl_tx_list_map,
198 		    BUS_DMASYNC_PREWRITE|BUS_DMASYNC_PREREAD);
199 
200 		/* start ? */
201 		CSR_WRITE_1(sc, sc->rl_txstart, RL_TXSTART_START);
202 	}
203 	if (do_lock)
204 		RL_UNLOCK(sc);
205 	return 0;
206 }
207 
208 
209 /*
210  * Reconcile kernel and user view of the receive ring.
211  */
212 static int
213 re_netmap_rxsync(struct ifnet *ifp, u_int ring_nr, int do_lock)
214 {
215 	struct rl_softc *sc = ifp->if_softc;
216 	struct rl_rxdesc *rxd = sc->rl_ldata.rl_rx_desc;
217 	struct netmap_adapter *na = NA(sc->rl_ifp);
218 	struct netmap_kring *kring = &na->rx_rings[ring_nr];
219 	struct netmap_ring *ring = kring->ring;
220 	int j, l, n, lim = kring->nkr_num_slots - 1;
221 	int force_update = do_lock || kring->nr_kflags & NKR_PENDINTR;
222 	u_int k = ring->cur, resvd = ring->reserved;
223 
224 	k = ring->cur;
225 	if (k > lim)
226 		return netmap_ring_reinit(kring);
227 
228 	if (do_lock)
229 		RL_LOCK(sc);
230 	/* XXX check sync modes */
231 	bus_dmamap_sync(sc->rl_ldata.rl_rx_list_tag,
232 	    sc->rl_ldata.rl_rx_list_map,
233 	    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
234 
235 	/*
236 	 * Import newly received packets into the netmap ring.
237 	 * j is an index in the netmap ring, l in the NIC ring.
238 	 *
239 	 * The device uses all the buffers in the ring, so we need
240 	 * another termination condition in addition to RL_RDESC_STAT_OWN
241 	 * cleared (all buffers could have it cleared. The easiest one
242 	 * is to limit the amount of data reported up to 'lim'
243 	 */
244 	l = sc->rl_ldata.rl_rx_prodidx; /* next pkt to check */
245 	j = netmap_idx_n2k(kring, l); /* the kring index */
246 	if (netmap_no_pendintr || force_update) {
247 		uint16_t slot_flags = kring->nkr_slot_flags;
248 
249 		for (n = kring->nr_hwavail; n < lim ; n++) {
250 			struct rl_desc *cur_rx = &sc->rl_ldata.rl_rx_list[l];
251 			uint32_t rxstat = le32toh(cur_rx->rl_cmdstat);
252 			uint32_t total_len;
253 
254 			if ((rxstat & RL_RDESC_STAT_OWN) != 0)
255 				break;
256 			total_len = rxstat & sc->rl_rxlenmask;
257 			/* XXX subtract crc */
258 			total_len = (total_len < 4) ? 0 : total_len - 4;
259 			kring->ring->slot[j].len = total_len;
260 			kring->ring->slot[j].flags = slot_flags;
261 			/*  sync was in re_newbuf() */
262 			bus_dmamap_sync(sc->rl_ldata.rl_rx_mtag,
263 			    rxd[l].rx_dmamap, BUS_DMASYNC_POSTREAD);
264 			j = (j == lim) ? 0 : j + 1;
265 			l = (l == lim) ? 0 : l + 1;
266 		}
267 		if (n != kring->nr_hwavail) {
268 			sc->rl_ldata.rl_rx_prodidx = l;
269 			sc->rl_ifp->if_ipackets += n - kring->nr_hwavail;
270 			kring->nr_hwavail = n;
271 		}
272 		kring->nr_kflags &= ~NKR_PENDINTR;
273 	}
274 
275 	/* skip past packets that userspace has released */
276 	j = kring->nr_hwcur;
277 	if (resvd > 0) {
278 		if (resvd + ring->avail >= lim + 1) {
279 			D("XXX invalid reserve/avail %d %d", resvd, ring->avail);
280 			ring->reserved = resvd = 0; // XXX panic...
281 		}
282 		k = (k >= resvd) ? k - resvd : k + lim + 1 - resvd;
283 	}
284 	if (j != k) { /* userspace has released some packets. */
285 		l = netmap_idx_k2n(kring, j); /* the NIC index */
286 		for (n = 0; j != k; n++) {
287 			struct netmap_slot *slot = ring->slot + j;
288 			struct rl_desc *desc = &sc->rl_ldata.rl_rx_list[l];
289 			int cmd = NETMAP_BUF_SIZE | RL_RDESC_CMD_OWN;
290 			uint64_t paddr;
291 			void *addr = PNMB(slot, &paddr);
292 
293 			if (addr == netmap_buffer_base) { /* bad buf */
294 				if (do_lock)
295 					RL_UNLOCK(sc);
296 				return netmap_ring_reinit(kring);
297 			}
298 
299 			if (l == lim)	/* mark end of ring */
300 				cmd |= RL_RDESC_CMD_EOR;
301 
302 			slot->flags &= ~NS_REPORT;
303 			if (slot->flags & NS_BUF_CHANGED) {
304 				netmap_reload_map(sc->rl_ldata.rl_rx_mtag,
305 					rxd[l].rx_dmamap, addr);
306 				desc->rl_bufaddr_lo = htole32(RL_ADDR_LO(paddr));
307 				desc->rl_bufaddr_hi = htole32(RL_ADDR_HI(paddr));
308 				slot->flags &= ~NS_BUF_CHANGED;
309 			}
310 			desc->rl_cmdstat = htole32(cmd);
311 			bus_dmamap_sync(sc->rl_ldata.rl_rx_mtag,
312 				rxd[l].rx_dmamap, BUS_DMASYNC_PREREAD);
313 			j = (j == lim) ? 0 : j + 1;
314 			l = (l == lim) ? 0 : l + 1;
315 		}
316 		kring->nr_hwavail -= n;
317 		kring->nr_hwcur = k;
318 		/* Flush the RX DMA ring */
319 
320 		bus_dmamap_sync(sc->rl_ldata.rl_rx_list_tag,
321 		    sc->rl_ldata.rl_rx_list_map,
322 		    BUS_DMASYNC_PREWRITE|BUS_DMASYNC_PREREAD);
323 	}
324 	/* tell userspace that there are new packets */
325 	ring->avail = kring->nr_hwavail - resvd;
326 	if (do_lock)
327 		RL_UNLOCK(sc);
328 	return 0;
329 }
330 
331 /*
332  * Additional routines to init the tx and rx rings.
333  * In other drivers we do that inline in the main code.
334  */
335 static void
336 re_netmap_tx_init(struct rl_softc *sc)
337 {
338 	struct rl_txdesc *txd;
339 	struct rl_desc *desc;
340 	int i, n;
341 	struct netmap_adapter *na = NA(sc->rl_ifp);
342 	struct netmap_slot *slot = netmap_reset(na, NR_TX, 0, 0);
343 
344 	/* slot is NULL if we are not in netmap mode */
345 	if (!slot)
346 		return;
347 	/* in netmap mode, overwrite addresses and maps */
348 	txd = sc->rl_ldata.rl_tx_desc;
349 	desc = sc->rl_ldata.rl_tx_list;
350 	n = sc->rl_ldata.rl_tx_desc_cnt;
351 
352 	/* l points in the netmap ring, i points in the NIC ring */
353 	for (i = 0; i < n; i++) {
354 		uint64_t paddr;
355 		int l = netmap_idx_n2k(&na->tx_rings[0], i);
356 		void *addr = PNMB(slot + l, &paddr);
357 
358 		desc[i].rl_bufaddr_lo = htole32(RL_ADDR_LO(paddr));
359 		desc[i].rl_bufaddr_hi = htole32(RL_ADDR_HI(paddr));
360 		netmap_load_map(sc->rl_ldata.rl_tx_mtag,
361 			txd[i].tx_dmamap, addr);
362 	}
363 }
364 
365 static void
366 re_netmap_rx_init(struct rl_softc *sc)
367 {
368 	struct netmap_adapter *na = NA(sc->rl_ifp);
369 	struct netmap_slot *slot = netmap_reset(na, NR_RX, 0, 0);
370 	struct rl_desc *desc = sc->rl_ldata.rl_rx_list;
371 	uint32_t cmdstat;
372 	int i, n, max_avail;
373 
374 	if (!slot)
375 		return;
376 	n = sc->rl_ldata.rl_rx_desc_cnt;
377 	/*
378 	 * Userspace owned hwavail packets before the reset,
379 	 * so the NIC that last hwavail descriptors of the ring
380 	 * are still owned by the driver (and keep one empty).
381 	 */
382 	max_avail = n - 1 - na->rx_rings[0].nr_hwavail;
383 	for (i = 0; i < n; i++) {
384 		void *addr;
385 		uint64_t paddr;
386 		int l = netmap_idx_n2k(&na->rx_rings[0], i);
387 
388 		addr = PNMB(slot + l, &paddr);
389 
390 		netmap_reload_map(sc->rl_ldata.rl_rx_mtag,
391 		    sc->rl_ldata.rl_rx_desc[i].rx_dmamap, addr);
392 		bus_dmamap_sync(sc->rl_ldata.rl_rx_mtag,
393 		    sc->rl_ldata.rl_rx_desc[i].rx_dmamap, BUS_DMASYNC_PREREAD);
394 		desc[i].rl_bufaddr_lo = htole32(RL_ADDR_LO(paddr));
395 		desc[i].rl_bufaddr_hi = htole32(RL_ADDR_HI(paddr));
396 		cmdstat = NETMAP_BUF_SIZE;
397 		if (i == n - 1) /* mark the end of ring */
398 			cmdstat |= RL_RDESC_CMD_EOR;
399 		if (i < max_avail)
400 			cmdstat |= RL_RDESC_CMD_OWN;
401 		desc[i].rl_cmdstat = htole32(cmdstat);
402 	}
403 }
404 
405 
406 static void
407 re_netmap_attach(struct rl_softc *sc)
408 {
409 	struct netmap_adapter na;
410 
411 	bzero(&na, sizeof(na));
412 
413 	na.ifp = sc->rl_ifp;
414 	na.separate_locks = 0;
415 	na.num_tx_desc = sc->rl_ldata.rl_tx_desc_cnt;
416 	na.num_rx_desc = sc->rl_ldata.rl_rx_desc_cnt;
417 	na.nm_txsync = re_netmap_txsync;
418 	na.nm_rxsync = re_netmap_rxsync;
419 	na.nm_lock = re_netmap_lock_wrapper;
420 	na.nm_register = re_netmap_reg;
421 	netmap_attach(&na, 1);
422 }
423 /* end of file */
424