1 /*-
2  * Copyright (c) 2011, Bryan Venteicher <bryanv@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice unmodified, this list of conditions, and the following
10  *    disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #ifndef _IF_VTNETVAR_H
28 #define _IF_VTNETVAR_H
29 
30 struct vtnet_statistics {
31 	uint64_t	mbuf_alloc_failed;
32 
33 	uint64_t	rx_frame_too_large;
34 	uint64_t	rx_enq_replacement_failed;
35 	uint64_t	rx_mergeable_failed;
36 	uint64_t	rx_csum_bad_ethtype;
37 	uint64_t	rx_csum_bad_ipproto;
38 	uint64_t	rx_csum_bad_offset;
39 	uint64_t	rx_csum_failed;
40 	uint64_t	rx_csum_offloaded;
41 	uint64_t	rx_task_rescheduled;
42 
43 	uint64_t	tx_csum_offloaded;
44 	uint64_t	tx_tso_offloaded;
45 	uint64_t	tx_csum_bad_ethtype;
46 	uint64_t	tx_tso_bad_ethtype;
47 	uint64_t	tx_defragged;
48 	uint64_t	tx_defrag_failed;
49 	uint64_t	tx_task_rescheduled;
50 };
51 
52 struct irqmap {
53 	int irq;
54 	driver_intr_t *handler;
55 };
56 
57 struct vtnet_softc {
58 	device_t		vtnet_dev;
59 	struct ifnet		*vtnet_ifp;
60 	struct lwkt_serialize	vtnet_slz;
61 	struct lwkt_serialize	vtnet_rx_slz;
62 	struct lwkt_serialize	vtnet_tx_slz;
63 	struct lwkt_serialize	*serializes[3];
64 
65 	uint32_t		vtnet_flags;
66 #define VTNET_FLAG_LINK		0x0001
67 #define VTNET_FLAG_SUSPENDED	0x0002
68 #define VTNET_FLAG_MAC		0x0004
69 #define VTNET_FLAG_CTRL_VQ	0x0008
70 #define VTNET_FLAG_CTRL_RX	0x0010
71 #define VTNET_FLAG_CTRL_MAC	0x0020
72 #define VTNET_FLAG_VLAN_FILTER	0x0040
73 #define VTNET_FLAG_TSO_ECN	0x0080
74 #define VTNET_FLAG_MRG_RXBUFS	0x0100
75 #define VTNET_FLAG_LRO_NOMRG	0x0200
76 #define VTNET_FLAG_INDIRECT	0x0400
77 
78 	struct virtqueue	*vtnet_rx_vq;
79 	struct virtqueue	*vtnet_tx_vq;
80 	struct virtqueue	*vtnet_ctrl_vq;
81 
82 	/* controlq, rx, tx and config_change */
83 	int			vtnet_cpus[4];
84 	int			vtnet_nintr;
85 
86 	struct irqmap		vtnet_irqmap[2];
87 	struct lwkt_serialize	*vtnet_intr_slz[3];
88 
89 	int			vtnet_txhdrcount;
90 	struct vtnet_tx_header	*vtnet_txhdrarea;
91 	SLIST_HEAD(, vtnet_tx_header)
92 				vtnet_txhdr_free;
93 	struct vtnet_mac_filter *vtnet_macfilter;
94 
95 	int			vtnet_hdr_size;
96 	int			vtnet_tx_size;
97 	int			vtnet_tx_nsegs;
98 	int			vtnet_rx_process_limit;
99 	int			vtnet_rx_nsegs;
100 	int			vtnet_rx_mbuf_size;
101 	int			vtnet_rx_mbuf_count;
102 	int			vtnet_if_flags;
103 	struct ifsubq_watchdog	vtnet_tx_watchdog;
104 	uint64_t		vtnet_features;
105 
106 	struct vtnet_statistics	vtnet_stats;
107 
108 	eventhandler_tag	vtnet_vlan_attach;
109 	eventhandler_tag	vtnet_vlan_detach;
110 
111 	struct ifmedia		vtnet_media;
112 	/*
113 	 * Fake media type; the host does not provide us with
114 	 * any real media information.
115 	 */
116 #define VTNET_MEDIATYPE		(IFM_ETHER | IFM_1000_T | IFM_FDX)
117 	char			vtnet_hwaddr[ETHER_ADDR_LEN];
118 
119 	/*
120 	 * During reset, the host's VLAN filtering table is lost. The
121 	 * array below is used to restore all the VLANs configured on
122 	 * this interface after a reset.
123 	 */
124 #define VTNET_VLAN_SHADOW_SIZE	(4096 / 32)
125 	int			vtnet_nvlans;
126 	uint32_t		vtnet_vlan_shadow[VTNET_VLAN_SHADOW_SIZE];
127 };
128 
129 /*
130  * When mergeable buffers are not negotiated, the vtnet_rx_header structure
131  * below is placed at the beginning of the mbuf data. Use 2 bytes of pad to
132  * both keep the VirtIO header and the data non-contiguous and to keep the
133  * frame's payload 4 byte aligned.
134  *
135  * When mergeable buffers are negotiated, the host puts the VirtIO header in
136  * the beginning of the first mbuf's data.
137  */
138 #define VTNET_RX_HEADER_PAD	2
139 struct vtnet_rx_header {
140 	struct virtio_net_hdr	vrh_hdr;
141 	char			vrh_pad[VTNET_RX_HEADER_PAD];
142 } __packed;
143 
144 /*
145  * For each outgoing frame, the vtnet_tx_header below is allocated from
146  * a free-list.
147  */
148 struct vtnet_tx_header {
149 	union {
150 		struct virtio_net_hdr		hdr;
151 		struct virtio_net_hdr_mrg_rxbuf	mhdr;
152 	} vth_uhdr;
153 
154 	struct mbuf *vth_mbuf;
155 	SLIST_ENTRY(vtnet_tx_header) link;
156 };
157 
158 /*
159  * The VirtIO specification does not place a limit on the number of MAC
160  * addresses the guest driver may request to be filtered. In practice,
161  * the host is constrained by available resources. To simplify this driver,
162  * impose a reasonably high limit of MAC addresses we will filter before
163  * falling back to promiscuous or all-multicast modes.
164  */
165 #define VTNET_MAX_MAC_ENTRIES	128
166 
167 struct vtnet_mac_table {
168 	uint32_t	nentries;
169 	uint8_t		macs[VTNET_MAX_MAC_ENTRIES][ETHER_ADDR_LEN];
170 } __packed;
171 
172 struct vtnet_mac_filter {
173 	struct vtnet_mac_table	vmf_unicast;
174 	uint32_t		vmf_pad; /* Make tables non-contiguous. */
175 	struct vtnet_mac_table	vmf_multicast;
176 };
177 
178 #define VTNET_WATCHDOG_TIMEOUT	5
179 #define VTNET_CSUM_OFFLOAD	(CSUM_TCP | CSUM_UDP)
180 
181 /* Features desired/implemented by this driver. */
182 #define VTNET_FEATURES 		\
183     (VIRTIO_NET_F_MAC		| \
184      VIRTIO_NET_F_STATUS	| \
185      VIRTIO_NET_F_CTRL_VQ	| \
186      VIRTIO_NET_F_CTRL_RX	| \
187      VIRTIO_NET_F_CTRL_MAC_ADDR	| \
188      VIRTIO_NET_F_CTRL_VLAN	| \
189      VIRTIO_NET_F_CSUM		| \
190      VIRTIO_NET_F_HOST_TSO4	| \
191      VIRTIO_NET_F_HOST_TSO6	| \
192      VIRTIO_NET_F_HOST_ECN	| \
193      VIRTIO_NET_F_GUEST_CSUM	| \
194      VIRTIO_NET_F_GUEST_TSO4	| \
195      VIRTIO_NET_F_GUEST_TSO6	| \
196      VIRTIO_NET_F_GUEST_ECN	| \
197      VIRTIO_NET_F_MRG_RXBUF	| \
198      VIRTIO_RING_F_INDIRECT_DESC)
199 
200 /*
201  * The VIRTIO_NET_F_GUEST_TSO[46] features permit the host to send us
202  * frames larger than 1514 bytes. We do not yet support software LRO
203  * via tcp_lro_rx().
204  */
205 #define VTNET_LRO_FEATURES (VIRTIO_NET_F_GUEST_TSO4 | \
206 			    VIRTIO_NET_F_GUEST_TSO6 | VIRTIO_NET_F_GUEST_ECN)
207 
208 #define VTNET_MAX_MTU		65536
209 #define VTNET_MAX_RX_SIZE	65550
210 
211 /*
212  * Used to preallocate the Vq indirect descriptors. The first segment
213  * is reserved for the header.
214  */
215 #define VTNET_MRG_RX_SEGS	1
216 #define VTNET_MIN_RX_SEGS	2
217 #define VTNET_MAX_RX_SEGS	34
218 #define VTNET_MIN_TX_SEGS	4
219 #define VTNET_MAX_TX_SEGS	64
220 
221 #if 0	/* Copied from FreeBSD's net/if.h at some time, but not usable. */
222 #define IFCAP_LRO               0x00400 /* can do Large Receive Offload */
223 #define IFCAP_VLAN_HWFILTER     0x10000 /* interface hw can filter vlan tag */
224 #define IFCAP_VLAN_HWTSO        0x40000 /* can do IFCAP_TSO on VLANs */
225 #endif
226 
227 /*
228  * This allows lots of code to at least build, even if it's never executed
229  * at the moment.
230  */
231 #ifndef IFCAP_VLAN_HWFILTER
232 #define IFCAP_VLAN_HWFILTER	0
233 #endif
234 #ifndef IFCAP_VLAN_HWTSO
235 #define IFCAP_VLAN_HWTSO	0
236 #endif
237 
238 /*
239  * Assert we can receive and transmit the maximum with regular
240  * size clusters.
241  */
242 CTASSERT(((VTNET_MAX_RX_SEGS - 1) * MCLBYTES) >= VTNET_MAX_RX_SIZE);
243 CTASSERT(((VTNET_MAX_TX_SEGS - 1) * MCLBYTES) >= VTNET_MAX_MTU);
244 
245 /*
246  * Determine how many mbufs are in each receive buffer. For LRO without
247  * mergeable buffers, we must allocate an mbuf chain large enough to
248  * hold both the vtnet_rx_header and the maximum receivable data.
249  */
250 #define VTNET_NEEDED_RX_MBUFS(_sc)					\
251 	((_sc)->vtnet_flags & VTNET_FLAG_LRO_NOMRG) == 0 ? 1 :		\
252 	howmany(sizeof(struct vtnet_rx_header) + VTNET_MAX_RX_SIZE,	\
253 	(_sc)->vtnet_rx_mbuf_size)
254 
255 #endif /* _IF_VTNETVAR_H */
256