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authorLogan Gunthorpe <logang@deltatee.com>2019-08-12 11:30:43 -0600
committerBjorn Helgaas <bhelgaas@google.com>2019-08-16 08:41:26 -0500
commit7f73eac3a7137eabfb0c005c7ba55eb7994b9673 (patch)
tree71b1700c9f04a1a35c9abdc59a4b7104dff03901 /drivers/pci/p2pdma.c
parent2b9f4bb2a4fb77da4862f9ddf5209de2bcdaa0c0 (diff)
PCI/P2PDMA: Introduce pci_p2pdma_unmap_sg()
Add pci_p2pdma_unmap_sg() to the two places that call pci_p2pdma_map_sg(). This is a prep patch to introduce correct mappings for p2pdma transactions that go through the root complex. Link: https://lore.kernel.org/r/20190730163545.4915-10-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-10-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'drivers/pci/p2pdma.c')
-rw-r--r--drivers/pci/p2pdma.c18
1 files changed, 17 insertions, 1 deletions
diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c
index 94fbacbcbbd0..1eec7a5ec27e 100644
--- a/drivers/pci/p2pdma.c
+++ b/drivers/pci/p2pdma.c
@@ -800,7 +800,8 @@ EXPORT_SYMBOL_GPL(pci_p2pmem_publish);
* @dir: DMA direction
* @attrs: DMA attributes passed to dma_map_sg() (if called)
*
- * Scatterlists mapped with this function should not be unmapped in any way.
+ * Scatterlists mapped with this function should be unmapped using
+ * pci_p2pdma_unmap_sg_attrs().
*
* Returns the number of SG entries mapped or 0 on error.
*/
@@ -835,6 +836,21 @@ int pci_p2pdma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
EXPORT_SYMBOL_GPL(pci_p2pdma_map_sg_attrs);
/**
+ * pci_p2pdma_unmap_sg - unmap a PCI peer-to-peer scatterlist that was
+ * mapped with pci_p2pdma_map_sg()
+ * @dev: device doing the DMA request
+ * @sg: scatter list to map
+ * @nents: number of elements returned by pci_p2pdma_map_sg()
+ * @dir: DMA direction
+ * @attrs: DMA attributes passed to dma_unmap_sg() (if called)
+ */
+void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir, unsigned long attrs)
+{
+}
+EXPORT_SYMBOL_GPL(pci_p2pdma_unmap_sg_attrs);
+
+/**
* pci_p2pdma_enable_store - parse a configfs/sysfs attribute store
* to enable p2pdma
* @page: contents of the value to be stored