From: Jakub Kicinski Date: Fri, 1 Aug 2025 01:13:35 +0000 (-0700) Subject: net: devmem: fix DMA direction on unmapping X-Git-Tag: io_uring-6.17-20250815~26^2~15 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=fa516c0d8bf90da9d5b168757162205aafe5d0e1;p=linux-block.git net: devmem: fix DMA direction on unmapping Looks like we always unmap the DMA_BUF with DMA_FROM_DEVICE direction. While at it unexport __net_devmem_dmabuf_binding_free(), it's internal. Found by code inspection. Fixes: bd61848900bf ("net: devmem: Implement TX path") Acked-by: Stanislav Fomichev Reviewed-by: Mina Almasry Link: https://patch.msgid.link/20250801011335.2267515-1-kuba@kernel.org Signed-off-by: Jakub Kicinski --- diff --git a/net/core/devmem.c b/net/core/devmem.c index b3a62ca0df65..24c591ab38ae 100644 --- a/net/core/devmem.c +++ b/net/core/devmem.c @@ -70,14 +70,13 @@ void __net_devmem_dmabuf_binding_free(struct work_struct *wq) gen_pool_destroy(binding->chunk_pool); dma_buf_unmap_attachment_unlocked(binding->attachment, binding->sgt, - DMA_FROM_DEVICE); + binding->direction); dma_buf_detach(binding->dmabuf, binding->attachment); dma_buf_put(binding->dmabuf); xa_destroy(&binding->bound_rxqs); kvfree(binding->tx_vec); kfree(binding); } -EXPORT_SYMBOL(__net_devmem_dmabuf_binding_free); struct net_iov * net_devmem_alloc_dmabuf(struct net_devmem_dmabuf_binding *binding) @@ -208,6 +207,7 @@ net_devmem_bind_dmabuf(struct net_device *dev, mutex_init(&binding->lock); binding->dmabuf = dmabuf; + binding->direction = direction; binding->attachment = dma_buf_attach(binding->dmabuf, dev->dev.parent); if (IS_ERR(binding->attachment)) { @@ -312,7 +312,7 @@ err_tx_vec: kvfree(binding->tx_vec); err_unmap: dma_buf_unmap_attachment_unlocked(binding->attachment, binding->sgt, - DMA_FROM_DEVICE); + direction); err_detach: dma_buf_detach(dmabuf, binding->attachment); err_free_binding: diff --git a/net/core/devmem.h b/net/core/devmem.h index 0a3b28ba5c13..41cd6e1c9141 100644 --- a/net/core/devmem.h +++ b/net/core/devmem.h @@ -56,6 +56,9 @@ struct net_devmem_dmabuf_binding { */ u32 id; + /* DMA direction, FROM_DEVICE for Rx binding, TO_DEVICE for Tx. */ + enum dma_data_direction direction; + /* Array of net_iov pointers for this binding, sorted by virtual * address. This array is convenient to map the virtual addresses to * net_iovs in the TX path. @@ -165,10 +168,6 @@ static inline void net_devmem_put_net_iov(struct net_iov *niov) { } -static inline void __net_devmem_dmabuf_binding_free(struct work_struct *wq) -{ -} - static inline struct net_devmem_dmabuf_binding * net_devmem_bind_dmabuf(struct net_device *dev, enum dma_data_direction direction,