1 files changed, 107 insertions, 0 deletions
diff --git a/include/rdma/ib_umem.h b/include/rdma/ib_umem.h
new file mode 100644
index 000000000..70597508c
--- /dev/null
+++ b/include/rdma/ib_umem.h
@@ -0,0 +1,107 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/*
+ * Copyright (c) 2007 Cisco Systems.  All rights reserved.
+ */
+
+#ifndef IB_UMEM_H
+#define IB_UMEM_H
+
+#include <linux/list.h>
+#include <linux/scatterlist.h>
+#include <linux/workqueue.h>
+#include <rdma/ib_verbs.h>
+
+struct ib_ucontext;
+struct ib_umem_odp;
+
+struct ib_umem {
+	struct ib_device       *ibdev;
+	struct mm_struct       *owning_mm;
+	u64 iova;
+	size_t			length;
+	unsigned long		address;
+	u32 writable : 1;
+	u32 is_odp : 1;
+	struct work_struct	work;
+	struct sg_table sg_head;
+	int             nmap;
+	unsigned int    sg_nents;
+};
+
+/* Returns the offset of the umem start relative to the first page. */
+static inline int ib_umem_offset(struct ib_umem *umem)
+{
+	return umem->address & ~PAGE_MASK;
+}
+
+static inline size_t ib_umem_num_dma_blocks(struct ib_umem *umem,
+					    unsigned long pgsz)
+{
+	return (size_t)((ALIGN(umem->iova + umem->length, pgsz) -
+			 ALIGN_DOWN(umem->iova, pgsz))) /
+	       pgsz;
+}
+
+static inline size_t ib_umem_num_pages(struct ib_umem *umem)
+{
+	return ib_umem_num_dma_blocks(umem, PAGE_SIZE);
+}
+
+static inline void __rdma_umem_block_iter_start(struct ib_block_iter *biter,
+						struct ib_umem *umem,
+						unsigned long pgsz)
+{
+	__rdma_block_iter_start(biter, umem->sg_head.sgl, umem->nmap, pgsz);
+}
+
+/**
+ * rdma_umem_for_each_dma_block - iterate over contiguous DMA blocks of the umem
+ * @umem: umem to iterate over
+ * @pgsz: Page size to split the list into
+ *
+ * pgsz must be <= PAGE_SIZE or computed by ib_umem_find_best_pgsz(). The
+ * returned DMA blocks will be aligned to pgsz and span the range:
+ * ALIGN_DOWN(umem->address, pgsz) to ALIGN(umem->address + umem->length, pgsz)
+ *
+ * Performs exactly ib_umem_num_dma_blocks() iterations.
+ */
+#define rdma_umem_for_each_dma_block(umem, biter, pgsz)                        \
+	for (__rdma_umem_block_iter_start(biter, umem, pgsz);                  \
+	     __rdma_block_iter_next(biter);)
+
+#ifdef CONFIG_INFINIBAND_USER_MEM
+
+struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
+			    size_t size, int access);
+void ib_umem_release(struct ib_umem *umem);
+int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
+		      size_t length);
+unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
+				     unsigned long pgsz_bitmap,
+				     unsigned long virt);
+
+#else /* CONFIG_INFINIBAND_USER_MEM */
+
+#include <linux/err.h>
+
+static inline struct ib_umem *ib_umem_get(struct ib_device *device,
+					  unsigned long addr, size_t size,
+					  int access)
+{
+	return ERR_PTR(-EINVAL);
+}
+static inline void ib_umem_release(struct ib_umem *umem) { }
+static inline int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
+		      		    size_t length) {
+	return -EINVAL;
+}
+static inline unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
+						   unsigned long pgsz_bitmap,
+						   unsigned long virt)
+{
+	return 0;
+}
+
+#endif /* CONFIG_INFINIBAND_USER_MEM */
+
+#endif /* IB_UMEM_H */