v4.19.13 snapshot.
diff --git a/net/rds/ib_fmr.c b/net/rds/ib_fmr.c
new file mode 100644
index 0000000..e0f70c4
--- /dev/null
+++ b/net/rds/ib_fmr.c
@@ -0,0 +1,258 @@
+/*
+ * Copyright (c) 2016 Oracle.  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 "ib_mr.h"
+
+struct rds_ib_mr *rds_ib_alloc_fmr(struct rds_ib_device *rds_ibdev, int npages)
+{
+	struct rds_ib_mr_pool *pool;
+	struct rds_ib_mr *ibmr = NULL;
+	struct rds_ib_fmr *fmr;
+	int err = 0;
+
+	if (npages <= RDS_MR_8K_MSG_SIZE)
+		pool = rds_ibdev->mr_8k_pool;
+	else
+		pool = rds_ibdev->mr_1m_pool;
+
+	ibmr = rds_ib_try_reuse_ibmr(pool);
+	if (ibmr)
+		return ibmr;
+
+	ibmr = kzalloc_node(sizeof(*ibmr), GFP_KERNEL,
+			    rdsibdev_to_node(rds_ibdev));
+	if (!ibmr) {
+		err = -ENOMEM;
+		goto out_no_cigar;
+	}
+
+	fmr = &ibmr->u.fmr;
+	fmr->fmr = ib_alloc_fmr(rds_ibdev->pd,
+			(IB_ACCESS_LOCAL_WRITE |
+			 IB_ACCESS_REMOTE_READ |
+			 IB_ACCESS_REMOTE_WRITE |
+			 IB_ACCESS_REMOTE_ATOMIC),
+			&pool->fmr_attr);
+	if (IS_ERR(fmr->fmr)) {
+		err = PTR_ERR(fmr->fmr);
+		fmr->fmr = NULL;
+		pr_warn("RDS/IB: %s failed (err=%d)\n", __func__, err);
+		goto out_no_cigar;
+	}
+
+	ibmr->pool = pool;
+	if (pool->pool_type == RDS_IB_MR_8K_POOL)
+		rds_ib_stats_inc(s_ib_rdma_mr_8k_alloc);
+	else
+		rds_ib_stats_inc(s_ib_rdma_mr_1m_alloc);
+
+	return ibmr;
+
+out_no_cigar:
+	kfree(ibmr);
+	atomic_dec(&pool->item_count);
+
+	return ERR_PTR(err);
+}
+
+static int rds_ib_map_fmr(struct rds_ib_device *rds_ibdev,
+			  struct rds_ib_mr *ibmr, struct scatterlist *sg,
+			  unsigned int nents)
+{
+	struct ib_device *dev = rds_ibdev->dev;
+	struct rds_ib_fmr *fmr = &ibmr->u.fmr;
+	struct scatterlist *scat = sg;
+	u64 io_addr = 0;
+	u64 *dma_pages;
+	u32 len;
+	int page_cnt, sg_dma_len;
+	int i, j;
+	int ret;
+
+	sg_dma_len = ib_dma_map_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
+	if (unlikely(!sg_dma_len)) {
+		pr_warn("RDS/IB: %s failed!\n", __func__);
+		return -EBUSY;
+	}
+
+	len = 0;
+	page_cnt = 0;
+
+	for (i = 0; i < sg_dma_len; ++i) {
+		unsigned int dma_len = ib_sg_dma_len(dev, &scat[i]);
+		u64 dma_addr = ib_sg_dma_address(dev, &scat[i]);
+
+		if (dma_addr & ~PAGE_MASK) {
+			if (i > 0) {
+				ib_dma_unmap_sg(dev, sg, nents,
+						DMA_BIDIRECTIONAL);
+				return -EINVAL;
+			} else {
+				++page_cnt;
+			}
+		}
+		if ((dma_addr + dma_len) & ~PAGE_MASK) {
+			if (i < sg_dma_len - 1) {
+				ib_dma_unmap_sg(dev, sg, nents,
+						DMA_BIDIRECTIONAL);
+				return -EINVAL;
+			} else {
+				++page_cnt;
+			}
+		}
+
+		len += dma_len;
+	}
+
+	page_cnt += len >> PAGE_SHIFT;
+	if (page_cnt > ibmr->pool->fmr_attr.max_pages) {
+		ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
+		return -EINVAL;
+	}
+
+	dma_pages = kmalloc_array_node(sizeof(u64), page_cnt, GFP_ATOMIC,
+				       rdsibdev_to_node(rds_ibdev));
+	if (!dma_pages) {
+		ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
+		return -ENOMEM;
+	}
+
+	page_cnt = 0;
+	for (i = 0; i < sg_dma_len; ++i) {
+		unsigned int dma_len = ib_sg_dma_len(dev, &scat[i]);
+		u64 dma_addr = ib_sg_dma_address(dev, &scat[i]);
+
+		for (j = 0; j < dma_len; j += PAGE_SIZE)
+			dma_pages[page_cnt++] =
+				(dma_addr & PAGE_MASK) + j;
+	}
+
+	ret = ib_map_phys_fmr(fmr->fmr, dma_pages, page_cnt, io_addr);
+	if (ret) {
+		ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
+		goto out;
+	}
+
+	/* Success - we successfully remapped the MR, so we can
+	 * safely tear down the old mapping.
+	 */
+	rds_ib_teardown_mr(ibmr);
+
+	ibmr->sg = scat;
+	ibmr->sg_len = nents;
+	ibmr->sg_dma_len = sg_dma_len;
+	ibmr->remap_count++;
+
+	if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
+		rds_ib_stats_inc(s_ib_rdma_mr_8k_used);
+	else
+		rds_ib_stats_inc(s_ib_rdma_mr_1m_used);
+	ret = 0;
+
+out:
+	kfree(dma_pages);
+
+	return ret;
+}
+
+struct rds_ib_mr *rds_ib_reg_fmr(struct rds_ib_device *rds_ibdev,
+				 struct scatterlist *sg,
+				 unsigned long nents,
+				 u32 *key)
+{
+	struct rds_ib_mr *ibmr = NULL;
+	struct rds_ib_fmr *fmr;
+	int ret;
+
+	ibmr = rds_ib_alloc_fmr(rds_ibdev, nents);
+	if (IS_ERR(ibmr))
+		return ibmr;
+
+	ibmr->device = rds_ibdev;
+	fmr = &ibmr->u.fmr;
+	ret = rds_ib_map_fmr(rds_ibdev, ibmr, sg, nents);
+	if (ret == 0)
+		*key = fmr->fmr->rkey;
+	else
+		rds_ib_free_mr(ibmr, 0);
+
+	return ibmr;
+}
+
+void rds_ib_unreg_fmr(struct list_head *list, unsigned int *nfreed,
+		      unsigned long *unpinned, unsigned int goal)
+{
+	struct rds_ib_mr *ibmr, *next;
+	struct rds_ib_fmr *fmr;
+	LIST_HEAD(fmr_list);
+	int ret = 0;
+	unsigned int freed = *nfreed;
+
+	/* String all ib_mr's onto one list and hand them to  ib_unmap_fmr */
+	list_for_each_entry(ibmr, list, unmap_list) {
+		fmr = &ibmr->u.fmr;
+		list_add(&fmr->fmr->list, &fmr_list);
+	}
+
+	ret = ib_unmap_fmr(&fmr_list);
+	if (ret)
+		pr_warn("RDS/IB: FMR invalidation failed (err=%d)\n", ret);
+
+	/* Now we can destroy the DMA mapping and unpin any pages */
+	list_for_each_entry_safe(ibmr, next, list, unmap_list) {
+		fmr = &ibmr->u.fmr;
+		*unpinned += ibmr->sg_len;
+		__rds_ib_teardown_mr(ibmr);
+		if (freed < goal ||
+		    ibmr->remap_count >= ibmr->pool->fmr_attr.max_maps) {
+			if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
+				rds_ib_stats_inc(s_ib_rdma_mr_8k_free);
+			else
+				rds_ib_stats_inc(s_ib_rdma_mr_1m_free);
+			list_del(&ibmr->unmap_list);
+			ib_dealloc_fmr(fmr->fmr);
+			kfree(ibmr);
+			freed++;
+		}
+	}
+	*nfreed = freed;
+}
+
+void rds_ib_free_fmr_list(struct rds_ib_mr *ibmr)
+{
+	struct rds_ib_mr_pool *pool = ibmr->pool;
+
+	if (ibmr->remap_count >= pool->fmr_attr.max_maps)
+		llist_add(&ibmr->llnode, &pool->drop_list);
+	else
+		llist_add(&ibmr->llnode, &pool->free_list);
+}