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authorJason Gunthorpe <jgg@nvidia.com>2023-04-14 15:58:29 +0200
committerLeon Romanovsky <leon@kernel.org>2023-04-16 10:08:07 +0200
commit8d7c7c0eeb74281c846ef9231ce20536c79a99b4 (patch)
treeb80b6fee2ff23604fd054ea29593ec8b6ece33c7 /include/rdma
parentRDMA/rxe: Fix the error "trying to register non-static key in rxe_cleanup_task" (diff)
downloadlinux-8d7c7c0eeb74281c846ef9231ce20536c79a99b4.tar.xz
linux-8d7c7c0eeb74281c846ef9231ce20536c79a99b4.zip
RDMA: Add ib_virt_dma_to_page()
Make it clearer what is going on by adding a function to go back from the "virtual" dma_addr to a kva and another to a struct page. This is used in the ib_uses_virt_dma() style drivers (siw, rxe, hfi, qib). Call them instead of a naked casting and virt_to_page() when working with dma_addr values encoded by the various ib_map functions. This also fixes the virt_to_page() casting problem Linus Walleij has been chasing. Cc: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/0-v2-05ea785520ed+10-ib_virt_page_jgg@nvidia.com Signed-off-by: Leon Romanovsky <leon@kernel.org>
Diffstat (limited to 'include/rdma')
-rw-r--r--include/rdma/ib_verbs.h25
1 files changed, 25 insertions, 0 deletions
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 949cf4ffc536..1e7774ac808f 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -4036,6 +4036,31 @@ static inline bool ib_dma_pci_p2p_dma_supported(struct ib_device *dev)
}
/**
+ * ib_virt_dma_to_ptr - Convert a dma_addr to a kernel pointer
+ * @dma_addr: The DMA address
+ *
+ * Used by ib_uses_virt_dma() devices to get back to the kernel pointer after
+ * going through the dma_addr marshalling.
+ */
+static inline void *ib_virt_dma_to_ptr(u64 dma_addr)
+{
+ /* virt_dma mode maps the kvs's directly into the dma addr */
+ return (void *)(uintptr_t)dma_addr;
+}
+
+/**
+ * ib_virt_dma_to_page - Convert a dma_addr to a struct page
+ * @dma_addr: The DMA address
+ *
+ * Used by ib_uses_virt_dma() device to get back to the struct page after going
+ * through the dma_addr marshalling.
+ */
+static inline struct page *ib_virt_dma_to_page(u64 dma_addr)
+{
+ return virt_to_page(ib_virt_dma_to_ptr(dma_addr));
+}
+
+/**
* ib_dma_mapping_error - check a DMA addr for error
* @dev: The device for which the dma_addr was created
* @dma_addr: The DMA address to check