Le 25/04/2025 à 22:47, Mina Almasry a écrit :
Augment dmabuf binding to be able to handle TX. Additional to all the RX binding, we also create tx_vec needed for the TX path.
Provide API for sendmsg to be able to send dmabufs bound to this device:
- Provide a new dmabuf_tx_cmsg which includes the dmabuf to send from.
- MSG_ZEROCOPY with SCM_DEVMEM_DMABUF cmsg indicates send from dma-buf.
Devmem is uncopyable, so piggyback off the existing MSG_ZEROCOPY implementation, while disabling instances where MSG_ZEROCOPY falls back to copying.
...
@@ -270,24 +284,34 @@ net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd, niov->owner = &owner->area; page_pool_set_dma_addr_netmem(net_iov_to_netmem(niov), net_devmem_get_dma_addr(niov));
if (direction == DMA_TO_DEVICE)binding->tx_vec[owner->area.base_virtual / PAGE_SIZE + i] = niov;virtual += len; }
- err = xa_alloc_cyclic(&net_devmem_dmabuf_bindings, &binding->id,
binding, xa_limit_32b, &id_alloc_next,GFP_KERNEL);- if (err < 0)
goto err_free_id;- return binding;
+err_free_id:
- xa_erase(&net_devmem_dmabuf_bindings, binding->id);
Not sure this is correct now that xa_alloc_cyclic() is the last function which is called. I guess that that the last goto should be to err_free_chunks.
err_free_chunks: gen_pool_for_each_chunk(binding->chunk_pool, net_devmem_dmabuf_free_chunk_owner, NULL); gen_pool_destroy(binding->chunk_pool); +err_tx_vec:
- kvfree(binding->tx_vec); err_unmap: dma_buf_unmap_attachment_unlocked(binding->attachment, binding->sgt, DMA_FROM_DEVICE); err_detach: dma_buf_detach(dmabuf, binding->attachment);
-err_free_id:
- xa_erase(&net_devmem_dmabuf_bindings, binding->id); err_free_binding: kfree(binding); err_put_dmabuf:
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diff --git a/net/core/sock.c b/net/core/sock.c index b64df2463300b..9dd2989040357 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -3017,6 +3017,12 @@ int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg, if (!sk_set_prio_allowed(sk, *(u32 *)CMSG_DATA(cmsg))) return -EPERM; sockc->priority = *(u32 *)CMSG_DATA(cmsg);
break;- case SCM_DEVMEM_DMABUF:
if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))return -EINVAL;sockc->dmabuf_id = *(u32 *)CMSG_DATA(cmsg);
Nitpick: Unneeded newline, to be consistent with the surrounding code.
break;default: return -EINVAL;
...
CJ