io_uring/zcrx: extract netdev+area init into a helper

In preparation to following patches, add a function that is responsibly
for looking up a netdev, creating an area, DMA mapping it and opening a
queue.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://patch.msgid.link/88cb6f746ecb496a9030756125419df273d0b003.1774261953.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/zcrx.c b/io_uring/zcrx.c
index a6a08ee48b34f1d9c630725349b7932ba0b7f5e1..b0f889b11b7300a6b3d95dcbe2f2112c4138298b 100644 (file)
--- a/io_uring/zcrx.c
+++ b/io_uring/zcrx.c
@@ -751,10 +751,50 @@ err:
        return ret;
 }
 
+static int zcrx_register_netdev(struct io_zcrx_ifq *ifq,
+                               struct io_uring_zcrx_ifq_reg *reg,
+                               struct io_uring_zcrx_area_reg *area)
+{
+       struct pp_memory_provider_params mp_param = {};
+       unsigned if_rxq = reg->if_rxq;
+       int ret;
+
+       ifq->netdev = netdev_get_by_index_lock(current->nsproxy->net_ns,
+                                               reg->if_idx);
+       if (!ifq->netdev)
+               return -ENODEV;
+
+       netdev_hold(ifq->netdev, &ifq->netdev_tracker, GFP_KERNEL);
+
+       ifq->dev = netdev_queue_get_dma_dev(ifq->netdev, if_rxq);
+       if (!ifq->dev) {
+               ret = -EOPNOTSUPP;
+               goto netdev_put_unlock;
+       }
+       get_device(ifq->dev);
+
+       ret = io_zcrx_create_area(ifq, area, reg);
+       if (ret)
+               goto netdev_put_unlock;
+
+       if (reg->rx_buf_len)
+               mp_param.rx_page_size = 1U << ifq->niov_shift;
+       mp_param.mp_ops = &io_uring_pp_zc_ops;
+       mp_param.mp_priv = ifq;
+       ret = __net_mp_open_rxq(ifq->netdev, if_rxq, &mp_param, NULL);
+       if (ret)
+               goto netdev_put_unlock;
+
+       ifq->if_rxq = if_rxq;
+       ret = 0;
+netdev_put_unlock:
+       netdev_unlock(ifq->netdev);
+       return ret;
+}
+
 int io_register_zcrx_ifq(struct io_ring_ctx *ctx,
                          struct io_uring_zcrx_ifq_reg __user *arg)
 {
-       struct pp_memory_provider_params mp_param = {};
        struct io_uring_zcrx_area_reg area;
        struct io_uring_zcrx_ifq_reg reg;
        struct io_uring_region_desc rd;
@@ -821,33 +861,9 @@ int io_register_zcrx_ifq(struct io_ring_ctx *ctx,
        if (ret)
                goto err;
 
-       ifq->netdev = netdev_get_by_index_lock(current->nsproxy->net_ns, reg.if_idx);
-       if (!ifq->netdev) {
-               ret = -ENODEV;
-               goto err;
-       }
-       netdev_hold(ifq->netdev, &ifq->netdev_tracker, GFP_KERNEL);
-
-       ifq->dev = netdev_queue_get_dma_dev(ifq->netdev, reg.if_rxq);
-       if (!ifq->dev) {
-               ret = -EOPNOTSUPP;
-               goto netdev_put_unlock;
-       }
-       get_device(ifq->dev);
-
-       ret = io_zcrx_create_area(ifq, &area, &reg);
-       if (ret)
-               goto netdev_put_unlock;
-
-       if (reg.rx_buf_len)
-               mp_param.rx_page_size = 1U << ifq->niov_shift;
-       mp_param.mp_ops = &io_uring_pp_zc_ops;
-       mp_param.mp_priv = ifq;
-       ret = __net_mp_open_rxq(ifq->netdev, reg.if_rxq, &mp_param, NULL);
+       ret = zcrx_register_netdev(ifq, &reg, &area);
        if (ret)
-               goto netdev_put_unlock;
-       netdev_unlock(ifq->netdev);
-       ifq->if_rxq = reg.if_rxq;
+               goto err;
 
        reg.zcrx_id = id;
 
@@ -867,8 +883,6 @@ int io_register_zcrx_ifq(struct io_ring_ctx *ctx,
                goto err;
        }
        return 0;
-netdev_put_unlock:
-       netdev_unlock(ifq->netdev);
 err:
        scoped_guard(mutex, &ctx->mmap_lock)
                xa_erase(&ctx->zcrx_ctxs, id);