v4.19.13 snapshot.
diff --git a/drivers/infiniband/hw/mlx5/mem.c b/drivers/infiniband/hw/mlx5/mem.c
new file mode 100644
index 0000000..f3dbd75
--- /dev/null
+++ b/drivers/infiniband/hw/mlx5/mem.c
@@ -0,0 +1,234 @@
+/*
+ * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/module.h>
+#include <rdma/ib_umem.h>
+#include <rdma/ib_umem_odp.h>
+#include "mlx5_ib.h"
+
+/* @umem: umem object to scan
+ * @addr: ib virtual address requested by the user
+ * @max_page_shift: high limit for page_shift - 0 means no limit
+ * @count: number of PAGE_SIZE pages covered by umem
+ * @shift: page shift for the compound pages found in the region
+ * @ncont: number of compund pages
+ * @order: log2 of the number of compound pages
+ */
+void mlx5_ib_cont_pages(struct ib_umem *umem, u64 addr,
+			unsigned long max_page_shift,
+			int *count, int *shift,
+			int *ncont, int *order)
+{
+	unsigned long tmp;
+	unsigned long m;
+	u64 base = ~0, p = 0;
+	u64 len, pfn;
+	int i = 0;
+	struct scatterlist *sg;
+	int entry;
+	unsigned long page_shift = umem->page_shift;
+
+	if (umem->odp_data) {
+		*ncont = ib_umem_page_count(umem);
+		*count = *ncont << (page_shift - PAGE_SHIFT);
+		*shift = page_shift;
+		if (order)
+			*order = ilog2(roundup_pow_of_two(*ncont));
+
+		return;
+	}
+
+	addr = addr >> page_shift;
+	tmp = (unsigned long)addr;
+	m = find_first_bit(&tmp, BITS_PER_LONG);
+	if (max_page_shift)
+		m = min_t(unsigned long, max_page_shift - page_shift, m);
+
+	for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry) {
+		len = sg_dma_len(sg) >> page_shift;
+		pfn = sg_dma_address(sg) >> page_shift;
+		if (base + p != pfn) {
+			/* If either the offset or the new
+			 * base are unaligned update m
+			 */
+			tmp = (unsigned long)(pfn | p);
+			if (!IS_ALIGNED(tmp, 1 << m))
+				m = find_first_bit(&tmp, BITS_PER_LONG);
+
+			base = pfn;
+			p = 0;
+		}
+
+		p += len;
+		i += len;
+	}
+
+	if (i) {
+		m = min_t(unsigned long, ilog2(roundup_pow_of_two(i)), m);
+
+		if (order)
+			*order = ilog2(roundup_pow_of_two(i) >> m);
+
+		*ncont = DIV_ROUND_UP(i, (1 << m));
+	} else {
+		m  = 0;
+
+		if (order)
+			*order = 0;
+
+		*ncont = 0;
+	}
+	*shift = page_shift + m;
+	*count = i;
+}
+
+#ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
+static u64 umem_dma_to_mtt(dma_addr_t umem_dma)
+{
+	u64 mtt_entry = umem_dma & ODP_DMA_ADDR_MASK;
+
+	if (umem_dma & ODP_READ_ALLOWED_BIT)
+		mtt_entry |= MLX5_IB_MTT_READ;
+	if (umem_dma & ODP_WRITE_ALLOWED_BIT)
+		mtt_entry |= MLX5_IB_MTT_WRITE;
+
+	return mtt_entry;
+}
+#endif
+
+/*
+ * Populate the given array with bus addresses from the umem.
+ *
+ * dev - mlx5_ib device
+ * umem - umem to use to fill the pages
+ * page_shift - determines the page size used in the resulting array
+ * offset - offset into the umem to start from,
+ *          only implemented for ODP umems
+ * num_pages - total number of pages to fill
+ * pas - bus addresses array to fill
+ * access_flags - access flags to set on all present pages.
+		  use enum mlx5_ib_mtt_access_flags for this.
+ */
+void __mlx5_ib_populate_pas(struct mlx5_ib_dev *dev, struct ib_umem *umem,
+			    int page_shift, size_t offset, size_t num_pages,
+			    __be64 *pas, int access_flags)
+{
+	unsigned long umem_page_shift = umem->page_shift;
+	int shift = page_shift - umem_page_shift;
+	int mask = (1 << shift) - 1;
+	int i, k, idx;
+	u64 cur = 0;
+	u64 base;
+	int len;
+	struct scatterlist *sg;
+	int entry;
+#ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
+	const bool odp = umem->odp_data != NULL;
+
+	if (odp) {
+		WARN_ON(shift != 0);
+		WARN_ON(access_flags != (MLX5_IB_MTT_READ | MLX5_IB_MTT_WRITE));
+
+		for (i = 0; i < num_pages; ++i) {
+			dma_addr_t pa = umem->odp_data->dma_list[offset + i];
+
+			pas[i] = cpu_to_be64(umem_dma_to_mtt(pa));
+		}
+		return;
+	}
+#endif
+
+	i = 0;
+	for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry) {
+		len = sg_dma_len(sg) >> umem_page_shift;
+		base = sg_dma_address(sg);
+
+		/* Skip elements below offset */
+		if (i + len < offset << shift) {
+			i += len;
+			continue;
+		}
+
+		/* Skip pages below offset */
+		if (i < offset << shift) {
+			k = (offset << shift) - i;
+			i = offset << shift;
+		} else {
+			k = 0;
+		}
+
+		for (; k < len; k++) {
+			if (!(i & mask)) {
+				cur = base + (k << umem_page_shift);
+				cur |= access_flags;
+				idx = (i >> shift) - offset;
+
+				pas[idx] = cpu_to_be64(cur);
+				mlx5_ib_dbg(dev, "pas[%d] 0x%llx\n",
+					    i >> shift, be64_to_cpu(pas[idx]));
+			}
+			i++;
+
+			/* Stop after num_pages reached */
+			if (i >> shift >= offset + num_pages)
+				return;
+		}
+	}
+}
+
+void mlx5_ib_populate_pas(struct mlx5_ib_dev *dev, struct ib_umem *umem,
+			  int page_shift, __be64 *pas, int access_flags)
+{
+	return __mlx5_ib_populate_pas(dev, umem, page_shift, 0,
+				      ib_umem_num_pages(umem), pas,
+				      access_flags);
+}
+int mlx5_ib_get_buf_offset(u64 addr, int page_shift, u32 *offset)
+{
+	u64 page_size;
+	u64 page_mask;
+	u64 off_size;
+	u64 off_mask;
+	u64 buf_off;
+
+	page_size = (u64)1 << page_shift;
+	page_mask = page_size - 1;
+	buf_off = addr & page_mask;
+	off_size = page_size >> 6;
+	off_mask = off_size - 1;
+
+	if (buf_off & off_mask)
+		return -EINVAL;
+
+	*offset = buf_off >> ilog2(off_size);
+	return 0;
+}