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Diffstat (limited to 'src/seastar/dpdk/lib/librte_vhost/vhost.c')
-rw-r--r--src/seastar/dpdk/lib/librte_vhost/vhost.c814
1 files changed, 814 insertions, 0 deletions
diff --git a/src/seastar/dpdk/lib/librte_vhost/vhost.c b/src/seastar/dpdk/lib/librte_vhost/vhost.c
new file mode 100644
index 000000000..163f4595e
--- /dev/null
+++ b/src/seastar/dpdk/lib/librte_vhost/vhost.c
@@ -0,0 +1,814 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2010-2017 Intel Corporation
+ */
+
+#include <linux/vhost.h>
+#include <linux/virtio_net.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#ifdef RTE_LIBRTE_VHOST_NUMA
+#include <numa.h>
+#include <numaif.h>
+#endif
+
+#include <rte_errno.h>
+#include <rte_ethdev.h>
+#include <rte_log.h>
+#include <rte_string_fns.h>
+#include <rte_memory.h>
+#include <rte_malloc.h>
+#include <rte_vhost.h>
+#include <rte_rwlock.h>
+
+#include "iotlb.h"
+#include "vhost.h"
+#include "vhost_user.h"
+
+struct virtio_net *vhost_devices[MAX_VHOST_DEVICE];
+
+/* Called with iotlb_lock read-locked */
+uint64_t
+__vhost_iova_to_vva(struct virtio_net *dev, struct vhost_virtqueue *vq,
+ uint64_t iova, uint64_t *size, uint8_t perm)
+{
+ uint64_t vva, tmp_size;
+
+ if (unlikely(!*size))
+ return 0;
+
+ tmp_size = *size;
+
+ vva = vhost_user_iotlb_cache_find(vq, iova, &tmp_size, perm);
+ if (tmp_size == *size)
+ return vva;
+
+ iova += tmp_size;
+
+ if (!vhost_user_iotlb_pending_miss(vq, iova, perm)) {
+ /*
+ * iotlb_lock is read-locked for a full burst,
+ * but it only protects the iotlb cache.
+ * In case of IOTLB miss, we might block on the socket,
+ * which could cause a deadlock with QEMU if an IOTLB update
+ * is being handled. We can safely unlock here to avoid it.
+ */
+ vhost_user_iotlb_rd_unlock(vq);
+
+ vhost_user_iotlb_pending_insert(vq, iova, perm);
+ if (vhost_user_iotlb_miss(dev, iova, perm)) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "IOTLB miss req failed for IOVA 0x%" PRIx64 "\n",
+ iova);
+ vhost_user_iotlb_pending_remove(vq, iova, 1, perm);
+ }
+
+ vhost_user_iotlb_rd_lock(vq);
+ }
+
+ return 0;
+}
+
+void
+cleanup_vq(struct vhost_virtqueue *vq, int destroy)
+{
+ if ((vq->callfd >= 0) && (destroy != 0))
+ close(vq->callfd);
+ if (vq->kickfd >= 0)
+ close(vq->kickfd);
+}
+
+/*
+ * Unmap any memory, close any file descriptors and
+ * free any memory owned by a device.
+ */
+void
+cleanup_device(struct virtio_net *dev, int destroy)
+{
+ uint32_t i;
+
+ vhost_backend_cleanup(dev);
+
+ for (i = 0; i < dev->nr_vring; i++)
+ cleanup_vq(dev->virtqueue[i], destroy);
+}
+
+void
+free_vq(struct virtio_net *dev, struct vhost_virtqueue *vq)
+{
+ if (vq_is_packed(dev))
+ rte_free(vq->shadow_used_packed);
+ else
+ rte_free(vq->shadow_used_split);
+ rte_free(vq->batch_copy_elems);
+ rte_mempool_free(vq->iotlb_pool);
+ rte_free(vq);
+}
+
+/*
+ * Release virtqueues and device memory.
+ */
+static void
+free_device(struct virtio_net *dev)
+{
+ uint32_t i;
+
+ for (i = 0; i < dev->nr_vring; i++)
+ free_vq(dev, dev->virtqueue[i]);
+
+ rte_free(dev);
+}
+
+static int
+vring_translate_split(struct virtio_net *dev, struct vhost_virtqueue *vq)
+{
+ uint64_t req_size, size;
+
+ req_size = sizeof(struct vring_desc) * vq->size;
+ size = req_size;
+ vq->desc = (struct vring_desc *)(uintptr_t)vhost_iova_to_vva(dev, vq,
+ vq->ring_addrs.desc_user_addr,
+ &size, VHOST_ACCESS_RW);
+ if (!vq->desc || size != req_size)
+ return -1;
+
+ req_size = sizeof(struct vring_avail);
+ req_size += sizeof(uint16_t) * vq->size;
+ if (dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX))
+ req_size += sizeof(uint16_t);
+ size = req_size;
+ vq->avail = (struct vring_avail *)(uintptr_t)vhost_iova_to_vva(dev, vq,
+ vq->ring_addrs.avail_user_addr,
+ &size, VHOST_ACCESS_RW);
+ if (!vq->avail || size != req_size)
+ return -1;
+
+ req_size = sizeof(struct vring_used);
+ req_size += sizeof(struct vring_used_elem) * vq->size;
+ if (dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX))
+ req_size += sizeof(uint16_t);
+ size = req_size;
+ vq->used = (struct vring_used *)(uintptr_t)vhost_iova_to_vva(dev, vq,
+ vq->ring_addrs.used_user_addr,
+ &size, VHOST_ACCESS_RW);
+ if (!vq->used || size != req_size)
+ return -1;
+
+ return 0;
+}
+
+static int
+vring_translate_packed(struct virtio_net *dev, struct vhost_virtqueue *vq)
+{
+ uint64_t req_size, size;
+
+ req_size = sizeof(struct vring_packed_desc) * vq->size;
+ size = req_size;
+ vq->desc_packed = (struct vring_packed_desc *)(uintptr_t)
+ vhost_iova_to_vva(dev, vq, vq->ring_addrs.desc_user_addr,
+ &size, VHOST_ACCESS_RW);
+ if (!vq->desc_packed || size != req_size)
+ return -1;
+
+ req_size = sizeof(struct vring_packed_desc_event);
+ size = req_size;
+ vq->driver_event = (struct vring_packed_desc_event *)(uintptr_t)
+ vhost_iova_to_vva(dev, vq, vq->ring_addrs.avail_user_addr,
+ &size, VHOST_ACCESS_RW);
+ if (!vq->driver_event || size != req_size)
+ return -1;
+
+ req_size = sizeof(struct vring_packed_desc_event);
+ size = req_size;
+ vq->device_event = (struct vring_packed_desc_event *)(uintptr_t)
+ vhost_iova_to_vva(dev, vq, vq->ring_addrs.used_user_addr,
+ &size, VHOST_ACCESS_RW);
+ if (!vq->device_event || size != req_size)
+ return -1;
+
+ return 0;
+}
+
+int
+vring_translate(struct virtio_net *dev, struct vhost_virtqueue *vq)
+{
+
+ if (!(dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM)))
+ goto out;
+
+ if (vq_is_packed(dev)) {
+ if (vring_translate_packed(dev, vq) < 0)
+ return -1;
+ } else {
+ if (vring_translate_split(dev, vq) < 0)
+ return -1;
+ }
+out:
+ vq->access_ok = 1;
+
+ return 0;
+}
+
+void
+vring_invalidate(struct virtio_net *dev, struct vhost_virtqueue *vq)
+{
+ if (dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))
+ vhost_user_iotlb_wr_lock(vq);
+
+ vq->access_ok = 0;
+ vq->desc = NULL;
+ vq->avail = NULL;
+ vq->used = NULL;
+
+ if (dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))
+ vhost_user_iotlb_wr_unlock(vq);
+}
+
+static void
+init_vring_queue(struct virtio_net *dev, uint32_t vring_idx)
+{
+ struct vhost_virtqueue *vq;
+
+ if (vring_idx >= VHOST_MAX_VRING) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "Failed not init vring, out of bound (%d)\n",
+ vring_idx);
+ return;
+ }
+
+ vq = dev->virtqueue[vring_idx];
+
+ memset(vq, 0, sizeof(struct vhost_virtqueue));
+
+ vq->kickfd = VIRTIO_UNINITIALIZED_EVENTFD;
+ vq->callfd = VIRTIO_UNINITIALIZED_EVENTFD;
+
+ vhost_user_iotlb_init(dev, vring_idx);
+ /* Backends are set to -1 indicating an inactive device. */
+ vq->backend = -1;
+
+ TAILQ_INIT(&vq->zmbuf_list);
+}
+
+static void
+reset_vring_queue(struct virtio_net *dev, uint32_t vring_idx)
+{
+ struct vhost_virtqueue *vq;
+ int callfd;
+
+ if (vring_idx >= VHOST_MAX_VRING) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "Failed not init vring, out of bound (%d)\n",
+ vring_idx);
+ return;
+ }
+
+ vq = dev->virtqueue[vring_idx];
+ callfd = vq->callfd;
+ init_vring_queue(dev, vring_idx);
+ vq->callfd = callfd;
+}
+
+int
+alloc_vring_queue(struct virtio_net *dev, uint32_t vring_idx)
+{
+ struct vhost_virtqueue *vq;
+
+ vq = rte_malloc(NULL, sizeof(struct vhost_virtqueue), 0);
+ if (vq == NULL) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "Failed to allocate memory for vring:%u.\n", vring_idx);
+ return -1;
+ }
+
+ dev->virtqueue[vring_idx] = vq;
+ init_vring_queue(dev, vring_idx);
+ rte_spinlock_init(&vq->access_lock);
+ vq->avail_wrap_counter = 1;
+ vq->used_wrap_counter = 1;
+ vq->signalled_used_valid = false;
+
+ dev->nr_vring += 1;
+
+ return 0;
+}
+
+/*
+ * Reset some variables in device structure, while keeping few
+ * others untouched, such as vid, ifname, nr_vring: they
+ * should be same unless the device is removed.
+ */
+void
+reset_device(struct virtio_net *dev)
+{
+ uint32_t i;
+
+ dev->features = 0;
+ dev->protocol_features = 0;
+ dev->flags &= VIRTIO_DEV_BUILTIN_VIRTIO_NET;
+
+ for (i = 0; i < dev->nr_vring; i++)
+ reset_vring_queue(dev, i);
+}
+
+/*
+ * Invoked when there is a new vhost-user connection established (when
+ * there is a new virtio device being attached).
+ */
+int
+vhost_new_device(void)
+{
+ struct virtio_net *dev;
+ int i;
+
+ for (i = 0; i < MAX_VHOST_DEVICE; i++) {
+ if (vhost_devices[i] == NULL)
+ break;
+ }
+
+ if (i == MAX_VHOST_DEVICE) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "Failed to find a free slot for new device.\n");
+ return -1;
+ }
+
+ dev = rte_zmalloc(NULL, sizeof(struct virtio_net), 0);
+ if (dev == NULL) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "Failed to allocate memory for new dev.\n");
+ return -1;
+ }
+
+ vhost_devices[i] = dev;
+ dev->vid = i;
+ dev->flags = VIRTIO_DEV_BUILTIN_VIRTIO_NET;
+ dev->slave_req_fd = -1;
+ dev->vdpa_dev_id = -1;
+ dev->postcopy_ufd = -1;
+ rte_spinlock_init(&dev->slave_req_lock);
+
+ return i;
+}
+
+void
+vhost_destroy_device_notify(struct virtio_net *dev)
+{
+ struct rte_vdpa_device *vdpa_dev;
+ int did;
+
+ if (dev->flags & VIRTIO_DEV_RUNNING) {
+ did = dev->vdpa_dev_id;
+ vdpa_dev = rte_vdpa_get_device(did);
+ if (vdpa_dev && vdpa_dev->ops->dev_close)
+ vdpa_dev->ops->dev_close(dev->vid);
+ dev->flags &= ~VIRTIO_DEV_RUNNING;
+ dev->notify_ops->destroy_device(dev->vid);
+ }
+}
+
+/*
+ * Invoked when there is the vhost-user connection is broken (when
+ * the virtio device is being detached).
+ */
+void
+vhost_destroy_device(int vid)
+{
+ struct virtio_net *dev = get_device(vid);
+
+ if (dev == NULL)
+ return;
+
+ vhost_destroy_device_notify(dev);
+
+ cleanup_device(dev, 1);
+ free_device(dev);
+
+ vhost_devices[vid] = NULL;
+}
+
+void
+vhost_attach_vdpa_device(int vid, int did)
+{
+ struct virtio_net *dev = get_device(vid);
+
+ if (dev == NULL)
+ return;
+
+ if (rte_vdpa_get_device(did) == NULL)
+ return;
+
+ dev->vdpa_dev_id = did;
+}
+
+void
+vhost_set_ifname(int vid, const char *if_name, unsigned int if_len)
+{
+ struct virtio_net *dev;
+ unsigned int len;
+
+ dev = get_device(vid);
+ if (dev == NULL)
+ return;
+
+ len = if_len > sizeof(dev->ifname) ?
+ sizeof(dev->ifname) : if_len;
+
+ strncpy(dev->ifname, if_name, len);
+ dev->ifname[sizeof(dev->ifname) - 1] = '\0';
+}
+
+void
+vhost_enable_dequeue_zero_copy(int vid)
+{
+ struct virtio_net *dev = get_device(vid);
+
+ if (dev == NULL)
+ return;
+
+ dev->dequeue_zero_copy = 1;
+}
+
+void
+vhost_set_builtin_virtio_net(int vid, bool enable)
+{
+ struct virtio_net *dev = get_device(vid);
+
+ if (dev == NULL)
+ return;
+
+ if (enable)
+ dev->flags |= VIRTIO_DEV_BUILTIN_VIRTIO_NET;
+ else
+ dev->flags &= ~VIRTIO_DEV_BUILTIN_VIRTIO_NET;
+}
+
+int
+rte_vhost_get_mtu(int vid, uint16_t *mtu)
+{
+ struct virtio_net *dev = get_device(vid);
+
+ if (dev == NULL || mtu == NULL)
+ return -ENODEV;
+
+ if (!(dev->flags & VIRTIO_DEV_READY))
+ return -EAGAIN;
+
+ if (!(dev->features & (1ULL << VIRTIO_NET_F_MTU)))
+ return -ENOTSUP;
+
+ *mtu = dev->mtu;
+
+ return 0;
+}
+
+int
+rte_vhost_get_numa_node(int vid)
+{
+#ifdef RTE_LIBRTE_VHOST_NUMA
+ struct virtio_net *dev = get_device(vid);
+ int numa_node;
+ int ret;
+
+ if (dev == NULL || numa_available() != 0)
+ return -1;
+
+ ret = get_mempolicy(&numa_node, NULL, 0, dev,
+ MPOL_F_NODE | MPOL_F_ADDR);
+ if (ret < 0) {
+ RTE_LOG(ERR, VHOST_CONFIG,
+ "(%d) failed to query numa node: %s\n",
+ vid, rte_strerror(errno));
+ return -1;
+ }
+
+ return numa_node;
+#else
+ RTE_SET_USED(vid);
+ return -1;
+#endif
+}
+
+uint32_t
+rte_vhost_get_queue_num(int vid)
+{
+ struct virtio_net *dev = get_device(vid);
+
+ if (dev == NULL)
+ return 0;
+
+ return dev->nr_vring / 2;
+}
+
+uint16_t
+rte_vhost_get_vring_num(int vid)
+{
+ struct virtio_net *dev = get_device(vid);
+
+ if (dev == NULL)
+ return 0;
+
+ return dev->nr_vring;
+}
+
+int
+rte_vhost_get_ifname(int vid, char *buf, size_t len)
+{
+ struct virtio_net *dev = get_device(vid);
+
+ if (dev == NULL || buf == NULL)
+ return -1;
+
+ len = RTE_MIN(len, sizeof(dev->ifname));
+
+ strncpy(buf, dev->ifname, len);
+ buf[len - 1] = '\0';
+
+ return 0;
+}
+
+int
+rte_vhost_get_negotiated_features(int vid, uint64_t *features)
+{
+ struct virtio_net *dev;
+
+ dev = get_device(vid);
+ if (dev == NULL || features == NULL)
+ return -1;
+
+ *features = dev->features;
+ return 0;
+}
+
+int
+rte_vhost_get_mem_table(int vid, struct rte_vhost_memory **mem)
+{
+ struct virtio_net *dev;
+ struct rte_vhost_memory *m;
+ size_t size;
+
+ dev = get_device(vid);
+ if (dev == NULL || mem == NULL)
+ return -1;
+
+ size = dev->mem->nregions * sizeof(struct rte_vhost_mem_region);
+ m = malloc(sizeof(struct rte_vhost_memory) + size);
+ if (!m)
+ return -1;
+
+ m->nregions = dev->mem->nregions;
+ memcpy(m->regions, dev->mem->regions, size);
+ *mem = m;
+
+ return 0;
+}
+
+int
+rte_vhost_get_vhost_vring(int vid, uint16_t vring_idx,
+ struct rte_vhost_vring *vring)
+{
+ struct virtio_net *dev;
+ struct vhost_virtqueue *vq;
+
+ dev = get_device(vid);
+ if (dev == NULL || vring == NULL)
+ return -1;
+
+ if (vring_idx >= VHOST_MAX_VRING)
+ return -1;
+
+ vq = dev->virtqueue[vring_idx];
+ if (!vq)
+ return -1;
+
+ vring->desc = vq->desc;
+ vring->avail = vq->avail;
+ vring->used = vq->used;
+ vring->log_guest_addr = vq->log_guest_addr;
+
+ vring->callfd = vq->callfd;
+ vring->kickfd = vq->kickfd;
+ vring->size = vq->size;
+
+ return 0;
+}
+
+int
+rte_vhost_vring_call(int vid, uint16_t vring_idx)
+{
+ struct virtio_net *dev;
+ struct vhost_virtqueue *vq;
+
+ dev = get_device(vid);
+ if (!dev)
+ return -1;
+
+ if (vring_idx >= VHOST_MAX_VRING)
+ return -1;
+
+ vq = dev->virtqueue[vring_idx];
+ if (!vq)
+ return -1;
+
+ if (vq_is_packed(dev))
+ vhost_vring_call_packed(dev, vq);
+ else
+ vhost_vring_call_split(dev, vq);
+
+ return 0;
+}
+
+uint16_t
+rte_vhost_avail_entries(int vid, uint16_t queue_id)
+{
+ struct virtio_net *dev;
+ struct vhost_virtqueue *vq;
+
+ dev = get_device(vid);
+ if (!dev)
+ return 0;
+
+ vq = dev->virtqueue[queue_id];
+ if (!vq->enabled)
+ return 0;
+
+ return *(volatile uint16_t *)&vq->avail->idx - vq->last_used_idx;
+}
+
+static inline void
+vhost_enable_notify_split(struct virtio_net *dev,
+ struct vhost_virtqueue *vq, int enable)
+{
+ if (!(dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX))) {
+ if (enable)
+ vq->used->flags &= ~VRING_USED_F_NO_NOTIFY;
+ else
+ vq->used->flags |= VRING_USED_F_NO_NOTIFY;
+ } else {
+ if (enable)
+ vhost_avail_event(vq) = vq->last_avail_idx;
+ }
+}
+
+static inline void
+vhost_enable_notify_packed(struct virtio_net *dev,
+ struct vhost_virtqueue *vq, int enable)
+{
+ uint16_t flags;
+
+ if (!enable) {
+ vq->device_event->flags = VRING_EVENT_F_DISABLE;
+ return;
+ }
+
+ flags = VRING_EVENT_F_ENABLE;
+ if (dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX)) {
+ flags = VRING_EVENT_F_DESC;
+ vq->device_event->off_wrap = vq->last_avail_idx |
+ vq->avail_wrap_counter << 15;
+ }
+
+ rte_smp_wmb();
+
+ vq->device_event->flags = flags;
+}
+
+int
+rte_vhost_enable_guest_notification(int vid, uint16_t queue_id, int enable)
+{
+ struct virtio_net *dev = get_device(vid);
+ struct vhost_virtqueue *vq;
+
+ if (!dev)
+ return -1;
+
+ vq = dev->virtqueue[queue_id];
+
+ if (vq_is_packed(dev))
+ vhost_enable_notify_packed(dev, vq, enable);
+ else
+ vhost_enable_notify_split(dev, vq, enable);
+
+ return 0;
+}
+
+void
+rte_vhost_log_write(int vid, uint64_t addr, uint64_t len)
+{
+ struct virtio_net *dev = get_device(vid);
+
+ if (dev == NULL)
+ return;
+
+ vhost_log_write(dev, addr, len);
+}
+
+void
+rte_vhost_log_used_vring(int vid, uint16_t vring_idx,
+ uint64_t offset, uint64_t len)
+{
+ struct virtio_net *dev;
+ struct vhost_virtqueue *vq;
+
+ dev = get_device(vid);
+ if (dev == NULL)
+ return;
+
+ if (vring_idx >= VHOST_MAX_VRING)
+ return;
+ vq = dev->virtqueue[vring_idx];
+ if (!vq)
+ return;
+
+ vhost_log_used_vring(dev, vq, offset, len);
+}
+
+uint32_t
+rte_vhost_rx_queue_count(int vid, uint16_t qid)
+{
+ struct virtio_net *dev;
+ struct vhost_virtqueue *vq;
+
+ dev = get_device(vid);
+ if (dev == NULL)
+ return 0;
+
+ if (unlikely(qid >= dev->nr_vring || (qid & 1) == 0)) {
+ RTE_LOG(ERR, VHOST_DATA, "(%d) %s: invalid virtqueue idx %d.\n",
+ dev->vid, __func__, qid);
+ return 0;
+ }
+
+ vq = dev->virtqueue[qid];
+ if (vq == NULL)
+ return 0;
+
+ if (unlikely(vq->enabled == 0 || vq->avail == NULL))
+ return 0;
+
+ return *((volatile uint16_t *)&vq->avail->idx) - vq->last_avail_idx;
+}
+
+int rte_vhost_get_vdpa_device_id(int vid)
+{
+ struct virtio_net *dev = get_device(vid);
+
+ if (dev == NULL)
+ return -1;
+
+ return dev->vdpa_dev_id;
+}
+
+int rte_vhost_get_log_base(int vid, uint64_t *log_base,
+ uint64_t *log_size)
+{
+ struct virtio_net *dev = get_device(vid);
+
+ if (dev == NULL || log_base == NULL || log_size == NULL)
+ return -1;
+
+ *log_base = dev->log_base;
+ *log_size = dev->log_size;
+
+ return 0;
+}
+
+int rte_vhost_get_vring_base(int vid, uint16_t queue_id,
+ uint16_t *last_avail_idx, uint16_t *last_used_idx)
+{
+ struct virtio_net *dev = get_device(vid);
+
+ if (dev == NULL || last_avail_idx == NULL || last_used_idx == NULL)
+ return -1;
+
+ *last_avail_idx = dev->virtqueue[queue_id]->last_avail_idx;
+ *last_used_idx = dev->virtqueue[queue_id]->last_used_idx;
+
+ return 0;
+}
+
+int rte_vhost_set_vring_base(int vid, uint16_t queue_id,
+ uint16_t last_avail_idx, uint16_t last_used_idx)
+{
+ struct virtio_net *dev = get_device(vid);
+
+ if (!dev)
+ return -1;
+
+ dev->virtqueue[queue_id]->last_avail_idx = last_avail_idx;
+ dev->virtqueue[queue_id]->last_used_idx = last_used_idx;
+
+ return 0;
+}
+
+int rte_vhost_extern_callback_register(int vid,
+ struct rte_vhost_user_extern_ops const * const ops, void *ctx)
+{
+ struct virtio_net *dev = get_device(vid);
+
+ if (dev == NULL || ops == NULL)
+ return -1;
+
+ dev->extern_ops = *ops;
+ dev->extern_data = ctx;
+ return 0;
+}