Merge tag 'for-next-dma_ops' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma

Pull rdma DMA mapping updates from Doug Ledford:
 "Drop IB DMA mapping code and use core DMA code instead.

  Bart Van Assche noted that the ib DMA mapping code was significantly
  similar enough to the core DMA mapping code that with a few changes it
  was possible to remove the IB DMA mapping code entirely and switch the
  RDMA stack to use the core DMA mapping code.

  This resulted in a nice set of cleanups, but touched the entire tree
  and has been kept separate for that reason."

* tag 'for-next-dma_ops' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (37 commits)
  IB/rxe, IB/rdmavt: Use dma_virt_ops instead of duplicating it
  IB/core: Remove ib_device.dma_device
  nvme-rdma: Switch from dma_device to dev.parent
  RDS: net: Switch from dma_device to dev.parent
  IB/srpt: Modify a debug statement
  IB/srp: Switch from dma_device to dev.parent
  IB/iser: Switch from dma_device to dev.parent
  IB/IPoIB: Switch from dma_device to dev.parent
  IB/rxe: Switch from dma_device to dev.parent
  IB/vmw_pvrdma: Switch from dma_device to dev.parent
  IB/usnic: Switch from dma_device to dev.parent
  IB/qib: Switch from dma_device to dev.parent
  IB/qedr: Switch from dma_device to dev.parent
  IB/ocrdma: Switch from dma_device to dev.parent
  IB/nes: Remove a superfluous assignment statement
  IB/mthca: Switch from dma_device to dev.parent
  IB/mlx5: Switch from dma_device to dev.parent
  IB/mlx4: Switch from dma_device to dev.parent
  IB/i40iw: Remove a superfluous assignment statement
  IB/hns: Switch from dma_device to dev.parent
  ...

1 files changed, 72 insertions, 0 deletions

diff --git a/lib/dma-virt.c b/lib/dma-virt.c
new file mode 100644
index 000000000000..dcd4df1f7174
--- /dev/null
+++ b/lib/dma-virt.c
@@ -0,0 +1,72 @@
+/*
+ *	lib/dma-virt.c
+ *
+ * DMA operations that map to virtual addresses without flushing memory.
+ */
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/dma-mapping.h>
+#include <linux/scatterlist.h>
+
+static void *dma_virt_alloc(struct device *dev, size_t size,
+			    dma_addr_t *dma_handle, gfp_t gfp,
+			    unsigned long attrs)
+{
+	void *ret;
+
+	ret = (void *)__get_free_pages(gfp, get_order(size));
+	if (ret)
+		*dma_handle = (uintptr_t)ret;
+	return ret;
+}
+
+static void dma_virt_free(struct device *dev, size_t size,
+			  void *cpu_addr, dma_addr_t dma_addr,
+			  unsigned long attrs)
+{
+	free_pages((unsigned long)cpu_addr, get_order(size));
+}
+
+static dma_addr_t dma_virt_map_page(struct device *dev, struct page *page,
+				    unsigned long offset, size_t size,
+				    enum dma_data_direction dir,
+				    unsigned long attrs)
+{
+	return (uintptr_t)(page_address(page) + offset);
+}
+
+static int dma_virt_map_sg(struct device *dev, struct scatterlist *sgl,
+			   int nents, enum dma_data_direction dir,
+			   unsigned long attrs)
+{
+	int i;
+	struct scatterlist *sg;
+
+	for_each_sg(sgl, sg, nents, i) {
+		BUG_ON(!sg_page(sg));
+		sg_dma_address(sg) = (uintptr_t)sg_virt(sg);
+		sg_dma_len(sg) = sg->length;
+	}
+
+	return nents;
+}
+
+static int dma_virt_mapping_error(struct device *dev, dma_addr_t dma_addr)
+{
+	return false;
+}
+
+static int dma_virt_supported(struct device *dev, u64 mask)
+{
+	return true;
+}
+
+const struct dma_map_ops dma_virt_ops = {
+	.alloc			= dma_virt_alloc,
+	.free			= dma_virt_free,
+	.map_page		= dma_virt_map_page,
+	.map_sg			= dma_virt_map_sg,
+	.mapping_error		= dma_virt_mapping_error,
+	.dma_supported		= dma_virt_supported,
+};
+EXPORT_SYMBOL(dma_virt_ops);