xref: /trueos/sys/dev/netmap/if_em_netmap.h (revision 7a1ab70b9590c4c122be3d913b579be45424f95a)
1 /*
2  * Copyright (C) 2011-2014 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  *
29  * netmap support for: em.
30  *
31  * For more details on netmap support please see ixgbe_netmap.h
32  */
33 
34 
35 #include <net/netmap.h>
36 #include <sys/selinfo.h>
37 #include <vm/vm.h>
38 #include <vm/pmap.h>    /* vtophys ? */
39 #include <dev/netmap/netmap_kern.h>
40 
41 
42 // XXX do we need to block/unblock the tasks ?
43 static void
em_netmap_block_tasks(struct adapter * adapter)44 em_netmap_block_tasks(struct adapter *adapter)
45 {
46 	if (adapter->msix > 1) { /* MSIX */
47 		int i;
48 		struct tx_ring *txr = adapter->tx_rings;
49 		struct rx_ring *rxr = adapter->rx_rings;
50 
51 		for (i = 0; i < adapter->num_queues; i++, txr++, rxr++) {
52 			taskqueue_block(txr->tq);
53 			taskqueue_drain(txr->tq, &txr->tx_task);
54 			taskqueue_block(rxr->tq);
55 			taskqueue_drain(rxr->tq, &rxr->rx_task);
56 		}
57 	} else {	/* legacy */
58 		taskqueue_block(adapter->tq);
59 		taskqueue_drain(adapter->tq, &adapter->link_task);
60 		taskqueue_drain(adapter->tq, &adapter->que_task);
61 	}
62 }
63 
64 
65 static void
em_netmap_unblock_tasks(struct adapter * adapter)66 em_netmap_unblock_tasks(struct adapter *adapter)
67 {
68 	if (adapter->msix > 1) {
69 		struct tx_ring *txr = adapter->tx_rings;
70 		struct rx_ring *rxr = adapter->rx_rings;
71 		int i;
72 
73 		for (i = 0; i < adapter->num_queues; i++) {
74 			taskqueue_unblock(txr->tq);
75 			taskqueue_unblock(rxr->tq);
76 		}
77 	} else { /* legacy */
78 		taskqueue_unblock(adapter->tq);
79 	}
80 }
81 
82 
83 /*
84  * Register/unregister. We are already under netmap lock.
85  */
86 static int
em_netmap_reg(struct netmap_adapter * na,int onoff)87 em_netmap_reg(struct netmap_adapter *na, int onoff)
88 {
89 	struct ifnet *ifp = na->ifp;
90 	struct adapter *adapter = ifp->if_softc;
91 
92 	EM_CORE_LOCK(adapter);
93 	em_disable_intr(adapter);
94 
95 	/* Tell the stack that the interface is no longer active */
96 	ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
97 
98 	em_netmap_block_tasks(adapter);
99 	/* enable or disable flags and callbacks in na and ifp */
100 	if (onoff) {
101 		nm_set_native_flags(na);
102 	} else {
103 		nm_clear_native_flags(na);
104 	}
105 	em_init_locked(adapter);	/* also enable intr */
106 	em_netmap_unblock_tasks(adapter);
107 	EM_CORE_UNLOCK(adapter);
108 	return (ifp->if_drv_flags & IFF_DRV_RUNNING ? 0 : 1);
109 }
110 
111 
112 /*
113  * Reconcile kernel and user view of the transmit ring.
114  */
115 static int
em_netmap_txsync(struct netmap_kring * kring,int flags)116 em_netmap_txsync(struct netmap_kring *kring, int flags)
117 {
118 	struct netmap_adapter *na = kring->na;
119 	struct ifnet *ifp = na->ifp;
120 	struct netmap_ring *ring = kring->ring;
121 	u_int nm_i;	/* index into the netmap ring */
122 	u_int nic_i;	/* index into the NIC ring */
123 	u_int n;
124 	u_int const lim = kring->nkr_num_slots - 1;
125 	u_int const head = kring->rhead;
126 	/* generate an interrupt approximately every half ring */
127 	u_int report_frequency = kring->nkr_num_slots >> 1;
128 
129 	/* device-specific */
130 	struct adapter *adapter = ifp->if_softc;
131 	struct tx_ring *txr = &adapter->tx_rings[kring->ring_id];
132 
133 	bus_dmamap_sync(txr->txdma.dma_tag, txr->txdma.dma_map,
134 			BUS_DMASYNC_POSTREAD);
135 
136 	/*
137 	 * First part: process new packets to send.
138 	 */
139 
140 	nm_i = kring->nr_hwcur;
141 	if (nm_i != head) {	/* we have new packets to send */
142 		nic_i = netmap_idx_k2n(kring, nm_i);
143 		for (n = 0; nm_i != head; n++) {
144 			struct netmap_slot *slot = &ring->slot[nm_i];
145 			u_int len = slot->len;
146 			uint64_t paddr;
147 			void *addr = PNMB(na, slot, &paddr);
148 
149 			/* device-specific */
150 			struct e1000_tx_desc *curr = &txr->tx_base[nic_i];
151 			struct em_buffer *txbuf = &txr->tx_buffers[nic_i];
152 			int flags = (slot->flags & NS_REPORT ||
153 				nic_i == 0 || nic_i == report_frequency) ?
154 				E1000_TXD_CMD_RS : 0;
155 
156 			NM_CHECK_ADDR_LEN(na, addr, len);
157 
158 			if (slot->flags & NS_BUF_CHANGED) {
159 				curr->buffer_addr = htole64(paddr);
160 				/* buffer has changed, reload map */
161 				netmap_reload_map(na, txr->txtag, txbuf->map, addr);
162 			}
163 			slot->flags &= ~(NS_REPORT | NS_BUF_CHANGED);
164 
165 			/* Fill the slot in the NIC ring. */
166 			curr->upper.data = 0;
167 			curr->lower.data = htole32(adapter->txd_cmd | len |
168 				(E1000_TXD_CMD_EOP | flags) );
169 			bus_dmamap_sync(txr->txtag, txbuf->map,
170 				BUS_DMASYNC_PREWRITE);
171 
172 			nm_i = nm_next(nm_i, lim);
173 			nic_i = nm_next(nic_i, lim);
174 		}
175 		kring->nr_hwcur = head;
176 
177 		/* synchronize the NIC ring */
178 		bus_dmamap_sync(txr->txdma.dma_tag, txr->txdma.dma_map,
179 			BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
180 
181 		/* (re)start the tx unit up to slot nic_i (excluded) */
182 		E1000_WRITE_REG(&adapter->hw, E1000_TDT(txr->me), nic_i);
183 	}
184 
185 	/*
186 	 * Second part: reclaim buffers for completed transmissions.
187 	 */
188 	if (flags & NAF_FORCE_RECLAIM || nm_kr_txempty(kring)) {
189 		/* record completed transmissions using TDH */
190 		nic_i = E1000_READ_REG(&adapter->hw, E1000_TDH(kring->ring_id));
191 		if (nic_i >= kring->nkr_num_slots) { /* XXX can it happen ? */
192 			D("TDH wrap %d", nic_i);
193 			nic_i -= kring->nkr_num_slots;
194 		}
195 		if (nic_i != txr->next_to_clean) {
196 			txr->next_to_clean = nic_i;
197 			kring->nr_hwtail = nm_prev(netmap_idx_n2k(kring, nic_i), lim);
198 		}
199 	}
200 
201 	nm_txsync_finalize(kring);
202 
203 	return 0;
204 }
205 
206 
207 /*
208  * Reconcile kernel and user view of the receive ring.
209  */
210 static int
em_netmap_rxsync(struct netmap_kring * kring,int flags)211 em_netmap_rxsync(struct netmap_kring *kring, int flags)
212 {
213 	struct netmap_adapter *na = kring->na;
214 	struct ifnet *ifp = na->ifp;
215 	struct netmap_ring *ring = kring->ring;
216 	u_int nm_i;	/* index into the netmap ring */
217 	u_int nic_i;	/* index into the NIC ring */
218 	u_int n;
219 	u_int const lim = kring->nkr_num_slots - 1;
220 	u_int const head = nm_rxsync_prologue(kring);
221 	int force_update = (flags & NAF_FORCE_READ) || kring->nr_kflags & NKR_PENDINTR;
222 
223 	/* device-specific */
224 	struct adapter *adapter = ifp->if_softc;
225 	struct rx_ring *rxr = &adapter->rx_rings[kring->ring_id];
226 
227 	if (head > lim)
228 		return netmap_ring_reinit(kring);
229 
230 	/* XXX check sync modes */
231 	bus_dmamap_sync(rxr->rxdma.dma_tag, rxr->rxdma.dma_map,
232 			BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
233 
234 	/*
235 	 * First part: import newly received packets.
236 	 */
237 	if (netmap_no_pendintr || force_update) {
238 		uint16_t slot_flags = kring->nkr_slot_flags;
239 
240 		nic_i = rxr->next_to_check;
241 		nm_i = netmap_idx_n2k(kring, nic_i);
242 
243 		for (n = 0; ; n++) { // XXX no need to count
244 			struct e1000_rx_desc *curr = &rxr->rx_base[nic_i];
245 			uint32_t staterr = le32toh(curr->status);
246 
247 			if ((staterr & E1000_RXD_STAT_DD) == 0)
248 				break;
249 			ring->slot[nm_i].len = le16toh(curr->length);
250 			ring->slot[nm_i].flags = slot_flags;
251 			bus_dmamap_sync(rxr->rxtag, rxr->rx_buffers[nic_i].map,
252 				BUS_DMASYNC_POSTREAD);
253 			nm_i = nm_next(nm_i, lim);
254 			/* make sure next_to_refresh follows next_to_check */
255 			rxr->next_to_refresh = nic_i;	// XXX
256 			nic_i = nm_next(nic_i, lim);
257 		}
258 		if (n) { /* update the state variables */
259 			rxr->next_to_check = nic_i;
260 			kring->nr_hwtail = nm_i;
261 		}
262 		kring->nr_kflags &= ~NKR_PENDINTR;
263 	}
264 
265 	/*
266 	 * Second part: skip past packets that userspace has released.
267 	 */
268 	nm_i = kring->nr_hwcur;
269 	if (nm_i != head) {
270 		nic_i = netmap_idx_k2n(kring, nm_i);
271 		for (n = 0; nm_i != head; n++) {
272 			struct netmap_slot *slot = &ring->slot[nm_i];
273 			uint64_t paddr;
274 			void *addr = PNMB(na, slot, &paddr);
275 
276 			struct e1000_rx_desc *curr = &rxr->rx_base[nic_i];
277 			struct em_buffer *rxbuf = &rxr->rx_buffers[nic_i];
278 
279 			if (addr == NETMAP_BUF_BASE(na)) /* bad buf */
280 				goto ring_reset;
281 
282 			if (slot->flags & NS_BUF_CHANGED) {
283 				/* buffer has changed, reload map */
284 				curr->buffer_addr = htole64(paddr);
285 				netmap_reload_map(na, rxr->rxtag, rxbuf->map, addr);
286 				slot->flags &= ~NS_BUF_CHANGED;
287 			}
288 			curr->status = 0;
289 			bus_dmamap_sync(rxr->rxtag, rxbuf->map,
290 			    BUS_DMASYNC_PREREAD);
291 			nm_i = nm_next(nm_i, lim);
292 			nic_i = nm_next(nic_i, lim);
293 		}
294 		kring->nr_hwcur = head;
295 
296 		bus_dmamap_sync(rxr->rxdma.dma_tag, rxr->rxdma.dma_map,
297 		    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
298 		/*
299 		 * IMPORTANT: we must leave one free slot in the ring,
300 		 * so move nic_i back by one unit
301 		 */
302 		nic_i = nm_prev(nic_i, lim);
303 		E1000_WRITE_REG(&adapter->hw, E1000_RDT(rxr->me), nic_i);
304 	}
305 
306 	/* tell userspace that there might be new packets */
307 	nm_rxsync_finalize(kring);
308 
309 	return 0;
310 
311 ring_reset:
312 	return netmap_ring_reinit(kring);
313 }
314 
315 
316 static void
em_netmap_attach(struct adapter * adapter)317 em_netmap_attach(struct adapter *adapter)
318 {
319 	struct netmap_adapter na;
320 
321 	bzero(&na, sizeof(na));
322 
323 	na.ifp = adapter->ifp;
324 	na.na_flags = NAF_BDG_MAYSLEEP;
325 	na.num_tx_desc = adapter->num_tx_desc;
326 	na.num_rx_desc = adapter->num_rx_desc;
327 	na.nm_txsync = em_netmap_txsync;
328 	na.nm_rxsync = em_netmap_rxsync;
329 	na.nm_register = em_netmap_reg;
330 	na.num_tx_rings = na.num_rx_rings = adapter->num_queues;
331 	netmap_attach(&na);
332 }
333 
334 /* end of file */
335