1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2014 Intel Corporation
10 #include <rte_atomic.h>
11 #include <rte_memory.h>
12 #include <rte_mempool.h>
14 #include "virtio_pci.h"
15 #include "virtio_ring.h"
16 #include "virtio_logs.h"
17 #include "virtio_rxtx.h"
22 * Per virtio_ring.h in Linux.
23 * For virtio_pci on SMP, we don't need to order with respect to MMIO
24 * accesses through relaxed memory I/O windows, so smp_mb() et al are
27 * For using virtio to talk to real devices (eg. vDPA) we do need real
31 virtio_mb(uint8_t weak_barriers)
40 virtio_rmb(uint8_t weak_barriers)
49 virtio_wmb(uint8_t weak_barriers)
57 #ifdef RTE_PMD_PACKET_PREFETCH
58 #define rte_packet_prefetch(p) rte_prefetch1(p)
60 #define rte_packet_prefetch(p) do {} while(0)
63 #define VIRTQUEUE_MAX_NAME_SZ 32
65 #ifdef RTE_VIRTIO_USER
67 * Return the physical address (or virtual address in case of
68 * virtio-user) of mbuf data buffer.
70 * The address is firstly casted to the word size (sizeof(uintptr_t))
71 * before casting it to uint64_t. This is to make it work with different
72 * combination of word size (64 bit and 32 bit) and virtio device
73 * (virtio-pci and virtio-user).
75 #define VIRTIO_MBUF_ADDR(mb, vq) \
76 ((uint64_t)(*(uintptr_t *)((uintptr_t)(mb) + (vq)->offset)))
78 #define VIRTIO_MBUF_ADDR(mb, vq) ((mb)->buf_iova)
82 * Return the physical address (or virtual address in case of
83 * virtio-user) of mbuf data buffer, taking care of mbuf data offset
85 #define VIRTIO_MBUF_DATA_DMA_ADDR(mb, vq) \
86 (VIRTIO_MBUF_ADDR(mb, vq) + (mb)->data_off)
88 #define VTNET_SQ_RQ_QUEUE_IDX 0
89 #define VTNET_SQ_TQ_QUEUE_IDX 1
90 #define VTNET_SQ_CQ_QUEUE_IDX 2
92 enum { VTNET_RQ = 0, VTNET_TQ = 1, VTNET_CQ = 2 };
94 * The maximum virtqueue size is 2^15. Use that value as the end of
95 * descriptor chain terminator since it will never be a valid index
96 * in the descriptor table. This is used to verify we are correctly
97 * handling vq_free_cnt.
99 #define VQ_RING_DESC_CHAIN_END 32768
102 * Control the RX mode, ie. promiscuous, allmulti, etc...
103 * All commands require an "out" sg entry containing a 1 byte
104 * state value, zero = disable, non-zero = enable. Commands
105 * 0 and 1 are supported with the VIRTIO_NET_F_CTRL_RX feature.
106 * Commands 2-5 are added with VIRTIO_NET_F_CTRL_RX_EXTRA.
108 #define VIRTIO_NET_CTRL_RX 0
109 #define VIRTIO_NET_CTRL_RX_PROMISC 0
110 #define VIRTIO_NET_CTRL_RX_ALLMULTI 1
111 #define VIRTIO_NET_CTRL_RX_ALLUNI 2
112 #define VIRTIO_NET_CTRL_RX_NOMULTI 3
113 #define VIRTIO_NET_CTRL_RX_NOUNI 4
114 #define VIRTIO_NET_CTRL_RX_NOBCAST 5
119 * The MAC filter table is managed by the hypervisor, the guest should
120 * assume the size is infinite. Filtering should be considered
121 * non-perfect, ie. based on hypervisor resources, the guest may
122 * received packets from sources not specified in the filter list.
124 * In addition to the class/cmd header, the TABLE_SET command requires
125 * two out scatterlists. Each contains a 4 byte count of entries followed
126 * by a concatenated byte stream of the ETH_ALEN MAC addresses. The
127 * first sg list contains unicast addresses, the second is for multicast.
128 * This functionality is present if the VIRTIO_NET_F_CTRL_RX feature
131 * The ADDR_SET command requests one out scatterlist, it contains a
132 * 6 bytes MAC address. This functionality is present if the
133 * VIRTIO_NET_F_CTRL_MAC_ADDR feature is available.
135 struct virtio_net_ctrl_mac {
137 uint8_t macs[][ETHER_ADDR_LEN];
138 } __attribute__((__packed__));
140 #define VIRTIO_NET_CTRL_MAC 1
141 #define VIRTIO_NET_CTRL_MAC_TABLE_SET 0
142 #define VIRTIO_NET_CTRL_MAC_ADDR_SET 1
145 * Control VLAN filtering
147 * The VLAN filter table is controlled via a simple ADD/DEL interface.
148 * VLAN IDs not added may be filtered by the hypervisor. Del is the
149 * opposite of add. Both commands expect an out entry containing a 2
150 * byte VLAN ID. VLAN filtering is available with the
151 * VIRTIO_NET_F_CTRL_VLAN feature bit.
153 #define VIRTIO_NET_CTRL_VLAN 2
154 #define VIRTIO_NET_CTRL_VLAN_ADD 0
155 #define VIRTIO_NET_CTRL_VLAN_DEL 1
158 * Control link announce acknowledgement
160 * The command VIRTIO_NET_CTRL_ANNOUNCE_ACK is used to indicate that
161 * driver has recevied the notification; device would clear the
162 * VIRTIO_NET_S_ANNOUNCE bit in the status field after it receives
165 #define VIRTIO_NET_CTRL_ANNOUNCE 3
166 #define VIRTIO_NET_CTRL_ANNOUNCE_ACK 0
168 struct virtio_net_ctrl_hdr {
171 } __attribute__((packed));
173 typedef uint8_t virtio_net_ctrl_ack;
175 #define VIRTIO_NET_OK 0
176 #define VIRTIO_NET_ERR 1
178 #define VIRTIO_MAX_CTRL_DATA 2048
180 struct virtio_pmd_ctrl {
181 struct virtio_net_ctrl_hdr hdr;
182 virtio_net_ctrl_ack status;
183 uint8_t data[VIRTIO_MAX_CTRL_DATA];
186 struct vq_desc_extra {
193 struct virtio_hw *hw; /**< virtio_hw structure pointer. */
194 struct vring vq_ring; /**< vring keeping desc, used and avail */
195 struct vring_packed ring_packed; /**< vring keeping descs */
196 bool avail_wrap_counter;
197 bool used_wrap_counter;
198 uint16_t event_flags_shadow;
199 uint16_t avail_used_flags;
201 * Last consumed descriptor in the used table,
202 * trails vq_ring.used->idx.
204 uint16_t vq_used_cons_idx;
205 uint16_t vq_nentries; /**< vring desc numbers */
206 uint16_t vq_free_cnt; /**< num of desc available */
207 uint16_t vq_avail_idx; /**< sync until needed */
208 uint16_t vq_free_thresh; /**< free threshold */
210 void *vq_ring_virt_mem; /**< linear address of vring*/
211 unsigned int vq_ring_size;
214 struct virtnet_rx rxq;
215 struct virtnet_tx txq;
216 struct virtnet_ctl cq;
219 rte_iova_t vq_ring_mem; /**< physical address of vring,
220 * or virtual address for virtio_user. */
223 * Head of the free chain in the descriptor table. If
224 * there are no free descriptors, this will be set to
225 * VQ_RING_DESC_CHAIN_END.
227 uint16_t vq_desc_head_idx;
228 uint16_t vq_desc_tail_idx;
229 uint16_t vq_queue_index; /**< PCI queue index */
230 uint16_t offset; /**< relative offset to obtain addr in mbuf */
231 uint16_t *notify_addr;
232 struct rte_mbuf **sw_ring; /**< RX software ring. */
233 struct vq_desc_extra vq_descx[0];
236 /* If multiqueue is provided by host, then we suppport it. */
237 #define VIRTIO_NET_CTRL_MQ 4
238 #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET 0
239 #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN 1
240 #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX 0x8000
243 * This is the first element of the scatter-gather list. If you don't
244 * specify GSO or CSUM features, you can simply ignore the header.
246 struct virtio_net_hdr {
247 #define VIRTIO_NET_HDR_F_NEEDS_CSUM 1 /**< Use csum_start,csum_offset*/
248 #define VIRTIO_NET_HDR_F_DATA_VALID 2 /**< Checksum is valid */
250 #define VIRTIO_NET_HDR_GSO_NONE 0 /**< Not a GSO frame */
251 #define VIRTIO_NET_HDR_GSO_TCPV4 1 /**< GSO frame, IPv4 TCP (TSO) */
252 #define VIRTIO_NET_HDR_GSO_UDP 3 /**< GSO frame, IPv4 UDP (UFO) */
253 #define VIRTIO_NET_HDR_GSO_TCPV6 4 /**< GSO frame, IPv6 TCP */
254 #define VIRTIO_NET_HDR_GSO_ECN 0x80 /**< TCP has ECN set */
256 uint16_t hdr_len; /**< Ethernet + IP + tcp/udp hdrs */
257 uint16_t gso_size; /**< Bytes to append to hdr_len per frame */
258 uint16_t csum_start; /**< Position to start checksumming from */
259 uint16_t csum_offset; /**< Offset after that to place checksum */
263 * This is the version of the header to use when the MRG_RXBUF
264 * feature has been negotiated.
266 struct virtio_net_hdr_mrg_rxbuf {
267 struct virtio_net_hdr hdr;
268 uint16_t num_buffers; /**< Number of merged rx buffers */
271 /* Region reserved to allow for transmit header and indirect ring */
272 #define VIRTIO_MAX_TX_INDIRECT 8
273 struct virtio_tx_region {
274 struct virtio_net_hdr_mrg_rxbuf tx_hdr;
276 struct vring_desc tx_indir[VIRTIO_MAX_TX_INDIRECT]
277 __attribute__((__aligned__(16)));
278 struct vring_packed_desc tx_indir_pq[VIRTIO_MAX_TX_INDIRECT]
279 __attribute__((__aligned__(16)));
284 __desc_is_used(struct vring_packed_desc *desc, bool wrap_counter)
286 uint16_t used, avail, flags;
289 used = !!(flags & VRING_DESC_F_USED(1));
290 avail = !!(flags & VRING_DESC_F_AVAIL(1));
292 return avail == used && used == wrap_counter;
296 desc_is_used(struct vring_packed_desc *desc, struct virtqueue *vq)
298 return __desc_is_used(desc, vq->used_wrap_counter);
303 vring_desc_init_packed(struct virtqueue *vq, int n)
306 for (i = 0; i < n - 1; i++) {
307 vq->ring_packed.desc_packed[i].id = i;
308 vq->vq_descx[i].next = i + 1;
310 vq->ring_packed.desc_packed[i].id = i;
311 vq->vq_descx[i].next = VQ_RING_DESC_CHAIN_END;
314 /* Chain all the descriptors in the ring with an END */
316 vring_desc_init_split(struct vring_desc *dp, uint16_t n)
320 for (i = 0; i < n - 1; i++)
321 dp[i].next = (uint16_t)(i + 1);
322 dp[i].next = VQ_RING_DESC_CHAIN_END;
326 * Tell the backend not to interrupt us.
329 virtqueue_disable_intr_packed(struct virtqueue *vq)
331 uint16_t *event_flags = &vq->ring_packed.driver_event->desc_event_flags;
333 *event_flags = RING_EVENT_FLAGS_DISABLE;
338 * Tell the backend not to interrupt us.
341 virtqueue_disable_intr(struct virtqueue *vq)
343 if (vtpci_packed_queue(vq->hw))
344 virtqueue_disable_intr_packed(vq);
346 vq->vq_ring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
350 * Tell the backend to interrupt. Implementation for packed virtqueues.
353 virtqueue_enable_intr_packed(struct virtqueue *vq)
355 uint16_t *event_flags = &vq->ring_packed.driver_event->desc_event_flags;
358 if (vq->event_flags_shadow == RING_EVENT_FLAGS_DISABLE) {
359 virtio_wmb(vq->hw->weak_barriers);
360 vq->event_flags_shadow = RING_EVENT_FLAGS_ENABLE;
361 *event_flags = vq->event_flags_shadow;
366 * Tell the backend to interrupt. Implementation for split virtqueues.
369 virtqueue_enable_intr_split(struct virtqueue *vq)
371 vq->vq_ring.avail->flags &= (~VRING_AVAIL_F_NO_INTERRUPT);
375 * Tell the backend to interrupt us.
378 virtqueue_enable_intr(struct virtqueue *vq)
380 if (vtpci_packed_queue(vq->hw))
381 virtqueue_enable_intr_packed(vq);
383 virtqueue_enable_intr_split(vq);
387 * Dump virtqueue internal structures, for debug purpose only.
389 void virtqueue_dump(struct virtqueue *vq);
391 * Get all mbufs to be freed.
393 struct rte_mbuf *virtqueue_detach_unused(struct virtqueue *vq);
395 /* Flush the elements in the used ring. */
396 void virtqueue_rxvq_flush(struct virtqueue *vq);
399 virtqueue_full(const struct virtqueue *vq)
401 return vq->vq_free_cnt == 0;
405 virtio_get_queue_type(struct virtio_hw *hw, uint16_t vtpci_queue_idx)
407 if (vtpci_queue_idx == hw->max_queue_pairs * 2)
409 else if (vtpci_queue_idx % 2 == 0)
415 #define VIRTQUEUE_NUSED(vq) ((uint16_t)((vq)->vq_ring.used->idx - (vq)->vq_used_cons_idx))
417 void vq_ring_free_chain(struct virtqueue *vq, uint16_t desc_idx);
418 void vq_ring_free_chain_packed(struct virtqueue *vq, uint16_t used_idx);
419 void vq_ring_free_inorder(struct virtqueue *vq, uint16_t desc_idx,
423 vq_update_avail_idx(struct virtqueue *vq)
425 virtio_wmb(vq->hw->weak_barriers);
426 vq->vq_ring.avail->idx = vq->vq_avail_idx;
430 vq_update_avail_ring(struct virtqueue *vq, uint16_t desc_idx)
434 * Place the head of the descriptor chain into the next slot and make
435 * it usable to the host. The chain is made available now rather than
436 * deferring to virtqueue_notify() in the hopes that if the host is
437 * currently running on another CPU, we can keep it processing the new
440 avail_idx = (uint16_t)(vq->vq_avail_idx & (vq->vq_nentries - 1));
441 if (unlikely(vq->vq_ring.avail->ring[avail_idx] != desc_idx))
442 vq->vq_ring.avail->ring[avail_idx] = desc_idx;
447 virtqueue_kick_prepare(struct virtqueue *vq)
450 * Ensure updated avail->idx is visible to vhost before reading
453 virtio_mb(vq->hw->weak_barriers);
454 return !(vq->vq_ring.used->flags & VRING_USED_F_NO_NOTIFY);
458 virtqueue_kick_prepare_packed(struct virtqueue *vq)
463 * Ensure updated data is visible to vhost before reading the flags.
465 virtio_mb(vq->hw->weak_barriers);
466 flags = vq->ring_packed.device_event->desc_event_flags;
468 return flags != RING_EVENT_FLAGS_DISABLE;
472 * virtqueue_kick_prepare*() or the virtio_wmb() should be called
473 * before this function to be sure that all the data is visible to vhost.
476 virtqueue_notify(struct virtqueue *vq)
478 VTPCI_OPS(vq->hw)->notify_queue(vq->hw, vq);
481 #ifdef RTE_LIBRTE_VIRTIO_DEBUG_DUMP
482 #define VIRTQUEUE_DUMP(vq) do { \
483 uint16_t used_idx, nused; \
484 used_idx = (vq)->vq_ring.used->idx; \
485 nused = (uint16_t)(used_idx - (vq)->vq_used_cons_idx); \
486 if (vtpci_packed_queue((vq)->hw)) { \
487 PMD_INIT_LOG(DEBUG, \
488 "VQ: - size=%d; free=%d; used_cons_idx=%d; avail_idx=%d;" \
489 "VQ: - avail_wrap_counter=%d; used_wrap_counter=%d", \
490 (vq)->vq_nentries, (vq)->vq_free_cnt, (vq)->vq_used_cons_idx, \
491 (vq)->vq_avail_idx, (vq)->avail_wrap_counter, \
492 (vq)->used_wrap_counter); \
495 PMD_INIT_LOG(DEBUG, \
496 "VQ: - size=%d; free=%d; used=%d; desc_head_idx=%d;" \
497 " avail.idx=%d; used_cons_idx=%d; used.idx=%d;" \
498 " avail.flags=0x%x; used.flags=0x%x", \
499 (vq)->vq_nentries, (vq)->vq_free_cnt, nused, \
500 (vq)->vq_desc_head_idx, (vq)->vq_ring.avail->idx, \
501 (vq)->vq_used_cons_idx, (vq)->vq_ring.used->idx, \
502 (vq)->vq_ring.avail->flags, (vq)->vq_ring.used->flags); \
505 #define VIRTQUEUE_DUMP(vq) do { } while (0)
508 #endif /* _VIRTQUEUE_H_ */