diff --git a/arch/arm64/configs/openeuler_defconfig b/arch/arm64/configs/openeuler_defconfig
index 69ff0b64ba591d28b79da3a8b66c446b3dafecac..fe3b216e39d54b578bf9fa8d99984cac41e998c9 100644
--- a/arch/arm64/configs/openeuler_defconfig
+++ b/arch/arm64/configs/openeuler_defconfig
@@ -5663,6 +5663,7 @@ CONFIG_INFINIBAND_ON_DEMAND_PAGING=y
 CONFIG_INFINIBAND_ADDR_TRANS=y
 CONFIG_INFINIBAND_ADDR_TRANS_CONFIGFS=y
 CONFIG_INFINIBAND_VIRT_DMA=y
+CONFIG_INFINIBAND_PEER_MEMORY=y
 # CONFIG_INFINIBAND_MTHCA is not set
 CONFIG_INFINIBAND_CXGB4=m
 # CONFIG_INFINIBAND_EFA is not set
diff --git a/arch/x86/configs/openeuler_defconfig b/arch/x86/configs/openeuler_defconfig
index f3b810d0cf47c277830cac0708cb5e4e7df5350b..d3de89970c1f96b5f0b0b0507ff9350b92dc6b7b 100644
--- a/arch/x86/configs/openeuler_defconfig
+++ b/arch/x86/configs/openeuler_defconfig
@@ -6286,6 +6286,7 @@ CONFIG_INFINIBAND_ON_DEMAND_PAGING=y
 CONFIG_INFINIBAND_ADDR_TRANS=y
 CONFIG_INFINIBAND_ADDR_TRANS_CONFIGFS=y
 CONFIG_INFINIBAND_VIRT_DMA=y
+CONFIG_INFINIBAND_PEER_MEMORY=y
 # CONFIG_INFINIBAND_MTHCA is not set
 # CONFIG_INFINIBAND_QIB is not set
 CONFIG_INFINIBAND_CXGB4=m
diff --git a/drivers/infiniband/Kconfig b/drivers/infiniband/Kconfig
index 194e824832d6bc848187f768e9ba7f673c0cd0fc..1213a8c334005bb44cf1fe7ad720690b74b9f062 100644
--- a/drivers/infiniband/Kconfig
+++ b/drivers/infiniband/Kconfig
@@ -73,6 +73,16 @@ config INFINIBAND_ADDR_TRANS_CONFIGFS
 	  This allows the user to config the default GID type that the CM
 	  uses for each device, when initiaing new connections.
 
+config INFINIBAND_PEER_MEMORY
+	bool "InfiniBand peer memory support"
+	depends on INFINIBAND_USER_MEM
+	default n
+	help
+	  Peer memory support for the InfinBand subsystem. This
+	  enables GPU drivers to provide peer memory operations
+	  and allows InfiniBand hardware drivers to utilize GPU
+	  peer memory.
+
 config INFINIBAND_VIRT_DMA
 	def_bool !HIGHMEM
 
diff --git a/drivers/infiniband/core/Makefile b/drivers/infiniband/core/Makefile
index ccf2670ef45efe83c4b1d88806ff23e4de2add63..3cc7c1837170a1cc68d0082018043646984cc76e 100644
--- a/drivers/infiniband/core/Makefile
+++ b/drivers/infiniband/core/Makefile
@@ -41,4 +41,5 @@ ib_uverbs-y :=			uverbs_main.o uverbs_cmd.o uverbs_marshall.o \
 				uverbs_std_types_wq.o \
 				uverbs_std_types_qp.o
 ib_uverbs-$(CONFIG_INFINIBAND_USER_MEM) += umem.o
+ib_uverbs-$(CONFIG_INFINIBAND_PEER_MEMORY) += peer_mem.o
 ib_uverbs-$(CONFIG_INFINIBAND_ON_DEMAND_PAGING) += umem_odp.o
diff --git a/drivers/infiniband/core/ib_peer_mem.h b/drivers/infiniband/core/ib_peer_mem.h
new file mode 100644
index 0000000000000000000000000000000000000000..248530a7f931a561727fbfb5f36a045ac07915f6
--- /dev/null
+++ b/drivers/infiniband/core/ib_peer_mem.h
@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/*
+ * Copyright (c) 2014-2020,  Mellanox Technologies. All rights reserved.
+ */
+#ifndef RDMA_IB_PEER_MEM_H
+#define RDMA_IB_PEER_MEM_H
+
+#include <rdma/peer_mem.h>
+#include <linux/kobject.h>
+#include <linux/xarray.h>
+#include <rdma/ib_umem.h>
+
+struct ib_peer_memory_statistics {
+	atomic64_t num_alloc_mrs;
+	atomic64_t num_dealloc_mrs;
+	atomic64_t num_reg_pages;
+	atomic64_t num_dereg_pages;
+	atomic64_t num_reg_bytes;
+	atomic64_t num_dereg_bytes;
+	unsigned long num_free_callbacks;
+};
+
+struct ib_peer_memory_client {
+	struct kobject kobj;
+	refcount_t usecnt;
+	struct completion usecnt_zero;
+	const struct peer_memory_client *peer_mem;
+	struct list_head core_peer_list;
+	struct ib_peer_memory_statistics stats;
+	struct xarray umem_xa;
+	u32 xa_cyclic_next;
+	bool invalidation_required;
+};
+
+enum ib_umem_mapped_state {
+	UMEM_PEER_UNMAPPED,
+	UMEM_PEER_MAPPED,
+	UMEM_PEER_INVALIDATED,
+};
+
+struct ib_umem_peer {
+	struct ib_umem umem;
+	struct kref kref;
+	/* peer memory that manages this umem */
+	struct ib_peer_memory_client *ib_peer_client;
+	void *peer_client_context;
+	umem_invalidate_func_t invalidation_func;
+	void *invalidation_private;
+	struct mutex mapping_lock;
+	enum ib_umem_mapped_state mapped_state;
+	u32 xa_id;
+	struct scatterlist *first_sg;
+	dma_addr_t first_dma_address;
+	unsigned int first_dma_length;
+	unsigned int first_length;
+	struct scatterlist *last_sg;
+	unsigned int last_dma_length;
+	unsigned int last_length;
+};
+
+struct ib_umem *ib_peer_umem_get(struct ib_umem *old_umem, int old_ret,
+				 unsigned long peer_mem_flags);
+void ib_peer_umem_release(struct ib_umem *umem);
+
+#endif
diff --git a/drivers/infiniband/core/peer_mem.c b/drivers/infiniband/core/peer_mem.c
new file mode 100644
index 0000000000000000000000000000000000000000..0108e6134979d028f7cb02b9f567cdf12009100d
--- /dev/null
+++ b/drivers/infiniband/core/peer_mem.c
@@ -0,0 +1,682 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/*
+ * Copyright (c) 2014-2020,  Mellanox Technologies. All rights reserved.
+ */
+
+#include <rdma/ib_verbs.h>
+#include <rdma/ib_umem.h>
+#include <linux/sched/mm.h>
+#include "ib_peer_mem.h"
+
+static DEFINE_MUTEX(peer_memory_mutex);
+static LIST_HEAD(peer_memory_list);
+static struct kobject *peers_kobj;
+#define PEER_NO_INVALIDATION_ID U32_MAX
+
+static int ib_invalidate_peer_memory(void *reg_handle, u64 core_context);
+
+struct peer_mem_attribute {
+	struct attribute attr;
+	ssize_t (*show)(struct ib_peer_memory_client *ib_peer_client,
+			struct peer_mem_attribute *attr, char *buf);
+	ssize_t (*store)(struct ib_peer_memory_client *ib_peer_client,
+			 struct peer_mem_attribute *attr, const char *buf,
+			 size_t count);
+};
+
+#define PEER_ATTR_RO(_name)                                                    \
+	struct peer_mem_attribute peer_attr_ ## _name = __ATTR_RO(_name)
+
+static ssize_t version_show(struct ib_peer_memory_client *ib_peer_client,
+			    struct peer_mem_attribute *attr, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%s\n",
+			 ib_peer_client->peer_mem->version);
+}
+static PEER_ATTR_RO(version);
+
+static ssize_t num_alloc_mrs_show(struct ib_peer_memory_client *ib_peer_client,
+				  struct peer_mem_attribute *attr, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%llu\n",
+			 (u64)atomic64_read(&ib_peer_client->stats.num_alloc_mrs));
+}
+static PEER_ATTR_RO(num_alloc_mrs);
+
+static ssize_t
+num_dealloc_mrs_show(struct ib_peer_memory_client *ib_peer_client,
+		     struct peer_mem_attribute *attr, char *buf)
+
+{
+	return scnprintf(buf, PAGE_SIZE, "%llu\n",
+			 (u64)atomic64_read(&ib_peer_client->stats.num_dealloc_mrs));
+}
+static PEER_ATTR_RO(num_dealloc_mrs);
+
+static ssize_t num_reg_pages_show(struct ib_peer_memory_client *ib_peer_client,
+				  struct peer_mem_attribute *attr, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%llu\n",
+			 (u64)atomic64_read(&ib_peer_client->stats.num_reg_pages));
+}
+static PEER_ATTR_RO(num_reg_pages);
+
+static ssize_t
+num_dereg_pages_show(struct ib_peer_memory_client *ib_peer_client,
+		     struct peer_mem_attribute *attr, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%llu\n",
+			 (u64)atomic64_read(&ib_peer_client->stats.num_dereg_pages));
+}
+static PEER_ATTR_RO(num_dereg_pages);
+
+static ssize_t num_reg_bytes_show(struct ib_peer_memory_client *ib_peer_client,
+				  struct peer_mem_attribute *attr, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%llu\n",
+			 (u64)atomic64_read(&ib_peer_client->stats.num_reg_bytes));
+}
+static PEER_ATTR_RO(num_reg_bytes);
+
+static ssize_t
+num_dereg_bytes_show(struct ib_peer_memory_client *ib_peer_client,
+		     struct peer_mem_attribute *attr, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%llu\n",
+			 (u64)atomic64_read(&ib_peer_client->stats.num_dereg_bytes));
+}
+static PEER_ATTR_RO(num_dereg_bytes);
+
+static ssize_t
+num_free_callbacks_show(struct ib_peer_memory_client *ib_peer_client,
+			struct peer_mem_attribute *attr, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%lu\n",
+			 ib_peer_client->stats.num_free_callbacks);
+}
+static PEER_ATTR_RO(num_free_callbacks);
+
+static struct attribute *peer_mem_attrs[] = {
+			&peer_attr_version.attr,
+			&peer_attr_num_alloc_mrs.attr,
+			&peer_attr_num_dealloc_mrs.attr,
+			&peer_attr_num_reg_pages.attr,
+			&peer_attr_num_dereg_pages.attr,
+			&peer_attr_num_reg_bytes.attr,
+			&peer_attr_num_dereg_bytes.attr,
+			&peer_attr_num_free_callbacks.attr,
+			NULL,
+};
+
+static const struct attribute_group peer_mem_attr_group = {
+	.attrs = peer_mem_attrs,
+};
+
+static ssize_t peer_attr_show(struct kobject *kobj, struct attribute *attr,
+			      char *buf)
+{
+	struct peer_mem_attribute *peer_attr =
+		container_of(attr, struct peer_mem_attribute, attr);
+
+	if (!peer_attr->show)
+		return -EIO;
+	return peer_attr->show(container_of(kobj, struct ib_peer_memory_client,
+					    kobj),
+			       peer_attr, buf);
+}
+
+static const struct sysfs_ops peer_mem_sysfs_ops = {
+	.show = peer_attr_show,
+};
+
+static void ib_peer_memory_client_release(struct kobject *kobj)
+{
+	struct ib_peer_memory_client *ib_peer_client =
+		container_of(kobj, struct ib_peer_memory_client, kobj);
+
+	kfree(ib_peer_client);
+}
+
+static struct kobj_type peer_mem_type = {
+	.sysfs_ops = &peer_mem_sysfs_ops,
+	.release = ib_peer_memory_client_release,
+};
+
+static int ib_memory_peer_check_mandatory(const struct peer_memory_client
+						     *peer_client)
+{
+#define PEER_MEM_MANDATORY_FUNC(x) {offsetof(struct peer_memory_client, x), #x}
+	int i;
+	static const struct {
+		size_t offset;
+		char *name;
+	} mandatory_table[] = {
+		PEER_MEM_MANDATORY_FUNC(acquire),
+		PEER_MEM_MANDATORY_FUNC(get_pages),
+		PEER_MEM_MANDATORY_FUNC(put_pages),
+		PEER_MEM_MANDATORY_FUNC(dma_map),
+		PEER_MEM_MANDATORY_FUNC(dma_unmap),
+	};
+
+	for (i = 0; i < ARRAY_SIZE(mandatory_table); ++i) {
+		if (!*(void **)((void *)peer_client +
+				mandatory_table[i].offset)) {
+			pr_err("Peer memory %s is missing mandatory function %s\n",
+			       peer_client->name, mandatory_table[i].name);
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+void *
+ib_register_peer_memory_client(const struct peer_memory_client *peer_client,
+			       invalidate_peer_memory *invalidate_callback)
+{
+	struct ib_peer_memory_client *ib_peer_client;
+	int ret;
+
+	if (ib_memory_peer_check_mandatory(peer_client))
+		return NULL;
+
+	ib_peer_client = kzalloc(sizeof(*ib_peer_client), GFP_KERNEL);
+	if (!ib_peer_client)
+		return NULL;
+	kobject_init(&ib_peer_client->kobj, &peer_mem_type);
+	refcount_set(&ib_peer_client->usecnt, 1);
+	init_completion(&ib_peer_client->usecnt_zero);
+	ib_peer_client->peer_mem = peer_client;
+	xa_init_flags(&ib_peer_client->umem_xa, XA_FLAGS_ALLOC);
+
+	/*
+	 * If the peer wants the invalidation_callback then all memory users
+	 * linked to that peer must support invalidation.
+	 */
+	if (invalidate_callback) {
+		*invalidate_callback = ib_invalidate_peer_memory;
+		ib_peer_client->invalidation_required = true;
+	}
+
+	mutex_lock(&peer_memory_mutex);
+	if (!peers_kobj) {
+		/* Created under /sys/kernel/mm */
+		peers_kobj = kobject_create_and_add("memory_peers", mm_kobj);
+		if (!peers_kobj)
+			goto err_unlock;
+	}
+
+	ret = kobject_add(&ib_peer_client->kobj, peers_kobj, peer_client->name);
+	if (ret)
+		goto err_parent;
+
+	ret = sysfs_create_group(&ib_peer_client->kobj,
+				 &peer_mem_attr_group);
+	if (ret)
+		goto err_parent;
+	list_add_tail(&ib_peer_client->core_peer_list, &peer_memory_list);
+	mutex_unlock(&peer_memory_mutex);
+	return ib_peer_client;
+
+err_parent:
+	if (list_empty(&peer_memory_list)) {
+		kobject_put(peers_kobj);
+		peers_kobj = NULL;
+	}
+err_unlock:
+	mutex_unlock(&peer_memory_mutex);
+	kobject_put(&ib_peer_client->kobj);
+	return NULL;
+}
+EXPORT_SYMBOL(ib_register_peer_memory_client);
+
+void ib_unregister_peer_memory_client(void *reg_handle)
+{
+	struct ib_peer_memory_client *ib_peer_client = reg_handle;
+
+	mutex_lock(&peer_memory_mutex);
+	list_del(&ib_peer_client->core_peer_list);
+	if (list_empty(&peer_memory_list)) {
+		kobject_put(peers_kobj);
+		peers_kobj = NULL;
+	}
+	mutex_unlock(&peer_memory_mutex);
+
+	/*
+	 * Wait for all umems to be destroyed before returning. Once
+	 * ib_unregister_peer_memory_client() returns no umems will call any
+	 * peer_mem ops.
+	 */
+	if (refcount_dec_and_test(&ib_peer_client->usecnt))
+		complete(&ib_peer_client->usecnt_zero);
+	wait_for_completion(&ib_peer_client->usecnt_zero);
+
+	kobject_put(&ib_peer_client->kobj);
+}
+EXPORT_SYMBOL(ib_unregister_peer_memory_client);
+
+static struct ib_peer_memory_client *
+ib_get_peer_client(unsigned long addr, size_t size,
+		   unsigned long peer_mem_flags, void **peer_client_context)
+{
+	struct ib_peer_memory_client *ib_peer_client;
+	int ret = 0;
+
+	mutex_lock(&peer_memory_mutex);
+	list_for_each_entry(ib_peer_client, &peer_memory_list,
+			    core_peer_list) {
+		if (ib_peer_client->invalidation_required &&
+		    (!(peer_mem_flags & IB_PEER_MEM_INVAL_SUPP)))
+			continue;
+		ret = ib_peer_client->peer_mem->acquire(addr, size, NULL, NULL,
+							peer_client_context);
+		if (ret > 0) {
+			refcount_inc(&ib_peer_client->usecnt);
+			mutex_unlock(&peer_memory_mutex);
+			return ib_peer_client;
+		}
+	}
+	mutex_unlock(&peer_memory_mutex);
+	return NULL;
+}
+
+static void ib_put_peer_client(struct ib_peer_memory_client *ib_peer_client,
+			       void *peer_client_context)
+{
+	if (ib_peer_client->peer_mem->release)
+		ib_peer_client->peer_mem->release(peer_client_context);
+	if (refcount_dec_and_test(&ib_peer_client->usecnt))
+		complete(&ib_peer_client->usecnt_zero);
+}
+
+static void ib_peer_umem_kref_release(struct kref *kref)
+{
+	struct ib_umem_peer *umem_p =
+		container_of(kref, struct ib_umem_peer, kref);
+
+	mutex_destroy(&umem_p->mapping_lock);
+	kfree(umem_p);
+}
+
+static void ib_unmap_peer_client(struct ib_umem_peer *umem_p,
+				 enum ib_umem_mapped_state cur_state,
+				 enum ib_umem_mapped_state to_state)
+{
+	struct ib_peer_memory_client *ib_peer_client = umem_p->ib_peer_client;
+	const struct peer_memory_client *peer_mem = ib_peer_client->peer_mem;
+	struct ib_umem *umem = &umem_p->umem;
+
+	if (cur_state == UMEM_PEER_MAPPED &&
+	    (to_state == UMEM_PEER_UNMAPPED ||
+	     to_state == UMEM_PEER_INVALIDATED)) {
+		/*
+		 * In the invalidated state we will never touch the sg again,
+		 * but the client might, so fix it anyhow.
+		 */
+		if (umem_p->last_sg) {
+			umem_p->last_sg->length = umem_p->last_length;
+			sg_dma_len(umem_p->last_sg) = umem_p->last_dma_length;
+		}
+
+		if (umem_p->first_sg) {
+			umem_p->first_sg->dma_address =
+				umem_p->first_dma_address;
+			umem_p->first_sg->length = umem_p->first_length;
+			sg_dma_len(umem_p->first_sg) = umem_p->first_dma_length;
+		}
+
+		if (to_state == UMEM_PEER_UNMAPPED) {
+			peer_mem->dma_unmap(&umem_p->umem.sg_head,
+					    umem_p->peer_client_context,
+					    umem_p->umem.ibdev->dma_device);
+			peer_mem->put_pages(&umem_p->umem.sg_head,
+					    umem_p->peer_client_context);
+		}
+
+		memset(&umem->sg_head, 0, sizeof(umem->sg_head));
+		atomic64_inc(&ib_peer_client->stats.num_dealloc_mrs);
+	}
+
+	if ((cur_state == UMEM_PEER_MAPPED && to_state == UMEM_PEER_UNMAPPED) ||
+	    (cur_state == UMEM_PEER_INVALIDATED &&
+	     to_state == UMEM_PEER_UNMAPPED)) {
+		atomic64_add(umem->sg_head.nents,
+			     &ib_peer_client->stats.num_dereg_pages);
+		atomic64_add(umem->length,
+			     &ib_peer_client->stats.num_dereg_bytes);
+	}
+	umem_p->mapped_state = to_state;
+}
+
+/*
+ * True if the client should do unmap itself after the invalidate callback
+ * returns. Clients operating in this mode need to use this locking pattern:
+ *
+ * client_invalidate:
+ *    mutex_lock(&client_lock)
+ *     invalidate_callback():
+ *       mutex_lock(mapping_lock)
+ *       mutex_unlock(mapping_lock)
+ *     client_dma_unmap()
+ *     client_put_pages()
+ *    mutex_unlock(&client_lock)
+ *
+ * ib_umem_stop_invalidation_notifier():
+ *  mutex_lock(mapping_lock)
+ *  mutex_unlock(mapping_lock)
+ *  peer_mem->dma_unmap():
+ *    mutex_lock(&client_lock)
+ *     client_dma_unmap()
+ *    mutex_unlock(&client_lock)
+ *  peer_mem->put_pages():
+ *    mutex_lock(&client_lock)
+ *     client_put_pages()
+ *    mutex_unlock(&client_lock)
+ *
+ * ib_peer_umem_release():
+ *  peer_mem->release():
+ *    mutex_lock(&client_lock)
+ *    mutex_unlock(&client_lock)
+ *
+ * Noting that dma_unmap/put_pages can be called even though invalidate has
+ * already done the unmap, and release() can be called concurrently with
+ * invalidate. The client must protect itself against these races.
+ */
+static bool ib_peer_unmap_on_invalidate(struct ib_umem_peer *umem_p)
+{
+	const struct peer_memory_client *peer_mem =
+		umem_p->ib_peer_client->peer_mem;
+	const struct peer_memory_client_ex *peer_mem_ex;
+
+	if (peer_mem->version[IB_PEER_MEMORY_VER_MAX - 1] == 0)
+		return false;
+	peer_mem_ex = container_of(peer_mem, const struct peer_memory_client_ex,
+				   client);
+	if (peer_mem_ex->ex_size <
+	    offsetofend(struct peer_memory_client_ex, flags))
+		return false;
+	return peer_mem_ex->flags & PEER_MEM_INVALIDATE_UNMAPS;
+}
+
+static int ib_invalidate_peer_memory(void *reg_handle, u64 core_context)
+{
+	struct ib_peer_memory_client *ib_peer_client = reg_handle;
+	struct ib_umem_peer *umem_p;
+
+	/*
+	 * The client is not required to fence against invalidation during
+	 * put_pages() as that would deadlock when we call put_pages() here.
+	 * Thus the core_context cannot be a umem pointer as we have no control
+	 * over the lifetime. Since we won't change the kABI for this to add a
+	 * proper kref, an xarray is used.
+	 */
+	xa_lock(&ib_peer_client->umem_xa);
+	ib_peer_client->stats.num_free_callbacks += 1;
+	umem_p = xa_load(&ib_peer_client->umem_xa, core_context);
+	if (!umem_p)
+		goto out_unlock;
+	kref_get(&umem_p->kref);
+	xa_unlock(&ib_peer_client->umem_xa);
+
+	mutex_lock(&umem_p->mapping_lock);
+	/*
+	 * For flows that require invalidation the invalidation_func should not
+	 * be NULL while the device can be doing DMA. The mapping_lock ensures
+	 * that the device is ready to receive an invalidation before one is
+	 * triggered here.
+	 */
+	if (umem_p->mapped_state == UMEM_PEER_MAPPED &&
+	    umem_p->invalidation_func)
+		umem_p->invalidation_func(&umem_p->umem,
+					  umem_p->invalidation_private);
+	if (ib_peer_unmap_on_invalidate(umem_p))
+		ib_unmap_peer_client(umem_p, umem_p->mapped_state,
+				     UMEM_PEER_INVALIDATED);
+	else
+		ib_unmap_peer_client(umem_p, umem_p->mapped_state,
+				     UMEM_PEER_UNMAPPED);
+	mutex_unlock(&umem_p->mapping_lock);
+	kref_put(&umem_p->kref, ib_peer_umem_kref_release);
+	return 0;
+
+out_unlock:
+	xa_unlock(&ib_peer_client->umem_xa);
+	return 0;
+}
+
+void ib_umem_activate_invalidation_notifier(struct ib_umem *umem,
+					    umem_invalidate_func_t func,
+					    void *priv)
+{
+	struct ib_umem_peer *umem_p =
+		container_of(umem, struct ib_umem_peer, umem);
+
+	if (WARN_ON(!umem->is_peer))
+		return;
+	if (umem_p->xa_id == PEER_NO_INVALIDATION_ID)
+		return;
+
+	umem_p->invalidation_func = func;
+	umem_p->invalidation_private = priv;
+	/* Pairs with the lock in ib_peer_umem_get() */
+	mutex_unlock(&umem_p->mapping_lock);
+
+	/* At this point func can be called asynchronously */
+}
+EXPORT_SYMBOL(ib_umem_activate_invalidation_notifier);
+
+/*
+ * Caller has blocked DMA and will no longer be able to handle invalidate
+ * callbacks. Callers using invalidation must call this function before calling
+ * ib_peer_umem_release(). ib_umem_activate_invalidation_notifier() is optional
+ * before doing this.
+ */
+void ib_umem_stop_invalidation_notifier(struct ib_umem *umem)
+{
+	struct ib_umem_peer *umem_p =
+		container_of(umem, struct ib_umem_peer, umem);
+	bool unmap_on_invalidate = ib_peer_unmap_on_invalidate(umem_p);
+	enum ib_umem_mapped_state cur_state;
+
+	if (umem_p->invalidation_func) {
+		mutex_lock(&umem_p->mapping_lock);
+		umem_p->invalidation_func = NULL;
+	} else if (umem_p->xa_id != PEER_NO_INVALIDATION_ID) {
+		mutex_lock(&umem_p->mapping_lock);
+	} else {
+		/*
+		 * Haven't called ib_umem_activate_invalidation_notifier() yet,
+		 * still have the lock
+		 */
+	}
+
+	if (!unmap_on_invalidate) {
+		ib_unmap_peer_client(umem_p, umem_p->mapped_state,
+				     UMEM_PEER_UNMAPPED);
+	} else {
+		/* Block ib_invalidate_peer_memory() */
+		cur_state = umem_p->mapped_state;
+		umem_p->mapped_state = UMEM_PEER_UNMAPPED;
+	}
+	mutex_unlock(&umem_p->mapping_lock);
+
+	if (unmap_on_invalidate)
+		ib_unmap_peer_client(umem_p, cur_state, UMEM_PEER_UNMAPPED);
+}
+EXPORT_SYMBOL(ib_umem_stop_invalidation_notifier);
+
+static void fix_peer_sgls(struct ib_umem_peer *umem_p, unsigned long peer_page_size)
+{
+	struct ib_umem *umem = &umem_p->umem;
+	struct scatterlist *sg;
+	int i;
+
+	for_each_sg(umem_p->umem.sg_head.sgl, sg, umem_p->umem.nmap, i) {
+		if (i == 0) {
+			unsigned long offset;
+
+			umem_p->first_sg = sg;
+			umem_p->first_dma_address = sg->dma_address;
+			umem_p->first_dma_length = sg_dma_len(sg);
+			umem_p->first_length = sg->length;
+
+			offset = ALIGN_DOWN(umem->address, PAGE_SIZE) -
+				 ALIGN_DOWN(umem->address, peer_page_size);
+			sg->dma_address += offset;
+			sg_dma_len(sg) -= offset;
+			sg->length -= offset;
+		}
+
+		if (i == umem_p->umem.nmap - 1) {
+			unsigned long trim;
+
+			umem_p->last_sg = sg;
+			umem_p->last_dma_length = sg_dma_len(sg);
+			umem_p->last_length = sg->length;
+
+			trim = ALIGN(umem->address + umem->length,
+				     peer_page_size) -
+			       ALIGN(umem->address + umem->length, PAGE_SIZE);
+			sg_dma_len(sg) -= trim;
+			sg->length -= trim;
+		}
+	}
+}
+
+struct ib_umem *ib_peer_umem_get(struct ib_umem *old_umem, int old_ret,
+				 unsigned long peer_mem_flags)
+{
+	struct ib_peer_memory_client *ib_peer_client;
+	unsigned long peer_page_size;
+	void *peer_client_context;
+	struct ib_umem_peer *umem_p;
+	int ret;
+
+	ib_peer_client =
+		ib_get_peer_client(old_umem->address, old_umem->length,
+				   peer_mem_flags, &peer_client_context);
+	if (!ib_peer_client)
+		return ERR_PTR(old_ret);
+
+	umem_p = kzalloc(sizeof(*umem_p), GFP_KERNEL);
+	if (!umem_p) {
+		ret = -ENOMEM;
+		goto err_client;
+	}
+
+	kref_init(&umem_p->kref);
+	umem_p->umem = *old_umem;
+	memset(&umem_p->umem.sg_head, 0, sizeof(umem_p->umem.sg_head));
+	umem_p->umem.is_peer = 1;
+	umem_p->ib_peer_client = ib_peer_client;
+	umem_p->peer_client_context = peer_client_context;
+	mutex_init(&umem_p->mapping_lock);
+	umem_p->xa_id = PEER_NO_INVALIDATION_ID;
+
+	mutex_lock(&umem_p->mapping_lock);
+	if (ib_peer_client->invalidation_required) {
+		ret = xa_alloc_cyclic(&ib_peer_client->umem_xa, &umem_p->xa_id,
+				      umem_p,
+				      XA_LIMIT(0, PEER_NO_INVALIDATION_ID - 1),
+				      &ib_peer_client->xa_cyclic_next,
+				      GFP_KERNEL);
+		if (ret < 0)
+			goto err_umem;
+	}
+
+	/*
+	 * We always request write permissions to the pages, to force breaking
+	 * of any CoW during the registration of the MR. For read-only MRs we
+	 * use the "force" flag to indicate that CoW breaking is required but
+	 * the registration should not fail if referencing read-only areas.
+	 */
+	ret = ib_peer_client->peer_mem->get_pages(umem_p->umem.address,
+						  umem_p->umem.length, 1,
+						  !umem_p->umem.writable, NULL,
+						  peer_client_context,
+						  umem_p->xa_id);
+	if (ret)
+		goto err_xa;
+
+	ret = ib_peer_client->peer_mem->dma_map(&umem_p->umem.sg_head,
+						peer_client_context,
+						umem_p->umem.ibdev->dma_device,
+						0, &umem_p->umem.nmap);
+	if (ret)
+		goto err_pages;
+
+	peer_page_size = ib_peer_client->peer_mem->get_page_size(peer_client_context);
+	if (peer_page_size != PAGE_SIZE)
+		fix_peer_sgls(umem_p, peer_page_size);
+
+	umem_p->mapped_state = UMEM_PEER_MAPPED;
+	atomic64_add(umem_p->umem.nmap, &ib_peer_client->stats.num_reg_pages);
+	atomic64_add(umem_p->umem.length, &ib_peer_client->stats.num_reg_bytes);
+	atomic64_inc(&ib_peer_client->stats.num_alloc_mrs);
+
+	/*
+	 * If invalidation is allowed then the caller must call
+	 * ib_umem_activate_invalidation_notifier() or ib_peer_umem_release() to
+	 * unlock this mutex. This call should be done after the last read to
+	 * sg_head, once the caller is ready for the invalidation function to be
+	 * called.
+	 */
+	if (umem_p->xa_id == PEER_NO_INVALIDATION_ID)
+		mutex_unlock(&umem_p->mapping_lock);
+
+	/*
+	 * On success the old umem is replaced with the new, larger, allocation
+	 */
+	kfree(old_umem);
+	return &umem_p->umem;
+
+err_pages:
+	ib_peer_client->peer_mem->put_pages(&umem_p->umem.sg_head,
+					    umem_p->peer_client_context);
+err_xa:
+	if (umem_p->xa_id != PEER_NO_INVALIDATION_ID)
+		xa_erase(&umem_p->ib_peer_client->umem_xa, umem_p->xa_id);
+err_umem:
+	mutex_unlock(&umem_p->mapping_lock);
+	kref_put(&umem_p->kref, ib_peer_umem_kref_release);
+err_client:
+	ib_put_peer_client(ib_peer_client, peer_client_context);
+	return ERR_PTR(ret);
+}
+
+void ib_peer_umem_release(struct ib_umem *umem)
+{
+	struct ib_umem_peer *umem_p =
+		container_of(umem, struct ib_umem_peer, umem);
+
+	/*
+	 * If ib_umem_activate_invalidation_notifier() is called then
+	 * ib_umem_stop_invalidation_notifier() must be called before release.
+	 */
+	WARN_ON(umem_p->invalidation_func);
+
+	/* For no invalidation cases, make sure it is unmapped */
+	ib_unmap_peer_client(umem_p, umem_p->mapped_state, UMEM_PEER_UNMAPPED);
+
+	if (umem_p->xa_id != PEER_NO_INVALIDATION_ID)
+		xa_erase(&umem_p->ib_peer_client->umem_xa, umem_p->xa_id);
+	ib_put_peer_client(umem_p->ib_peer_client, umem_p->peer_client_context);
+	umem_p->ib_peer_client = NULL;
+
+	/* Must match ib_umem_release() */
+	atomic64_sub(ib_umem_num_pages(umem), &umem->owning_mm->pinned_vm);
+	mmdrop(umem->owning_mm);
+
+	kref_put(&umem_p->kref, ib_peer_umem_kref_release);
+}
+
+/* Use it like this:
+ * struct peer_memory_client_ex peer_memory_test = {
+ *	.client = {
+ *		.version = "1.0",
+ *		.version[IB_PEER_MEMORY_VER_MAX-1] = 1,
+ *	},
+ *	.ex_size = sizeof(struct peer_memory_client_ex),
+ *	.flags = PEER_MEM_INVALIDATE_UNMAPS,
+ * };
+ */
diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c
index deda9eef5bd62928d8fd31189f2f23ffd44cab70..2ed282cd2940e5e48a7502d2bc3ae0596a454e66 100644
--- a/drivers/infiniband/core/umem.c
+++ b/drivers/infiniband/core/umem.c
@@ -44,6 +44,10 @@
 
 #include "uverbs.h"
 
+#ifdef CONFIG_INFINIBAND_PEER_MEMORY
+#include "ib_peer_mem.h"
+#endif
+
 static void __ib_umem_release(struct ib_device *dev, struct ib_umem *umem, int dirty)
 {
 	bool make_dirty = umem->writable && dirty;
@@ -131,15 +135,17 @@ unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
 EXPORT_SYMBOL(ib_umem_find_best_pgsz);
 
 /**
- * ib_umem_get - Pin and DMA map userspace memory.
+ * __ib_umem_get - Pin and DMA map userspace memory.
  *
  * @device: IB device to connect UMEM
  * @addr: userspace virtual address to start at
  * @size: length of region to pin
  * @access: IB_ACCESS_xxx flags for memory being pinned
+ * @peer_mem_flags: IB_PEER_MEM_xxx flags for memory being used
  */
-struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
-			    size_t size, int access)
+static struct ib_umem *__ib_umem_get(struct ib_device *device,
+				     unsigned long addr, size_t size, int access,
+				     unsigned long peer_mem_flags)
 {
 	struct ib_umem *umem;
 	struct page **page_list;
@@ -249,6 +255,26 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
 
 umem_release:
 	__ib_umem_release(device, umem, 0);
+#ifdef CONFIG_INFINIBAND_PEER_MEMORY
+	/*
+	 * If the address belongs to peer memory client, then the first
+	 * call to get_user_pages will fail. In this case, try to get
+	 * these pages from the peers.
+	 */
+	if (ret < 0 && peer_mem_flags & IB_PEER_MEM_ALLOW) {
+		struct ib_umem *new_umem;
+
+		new_umem = ib_peer_umem_get(umem, ret, peer_mem_flags);
+		if (IS_ERR(new_umem)) {
+			ret = PTR_ERR(new_umem);
+			goto vma;
+		}
+		umem = new_umem;
+		ret = 0;
+		goto out;
+	}
+vma:
+#endif
 	atomic64_sub(ib_umem_num_pages(umem), &mm->pinned_vm);
 out:
 	free_page((unsigned long) page_list);
@@ -259,8 +285,25 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
 	}
 	return ret ? ERR_PTR(ret) : umem;
 }
+
+struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
+			    size_t size, int access)
+{
+	return __ib_umem_get(device, addr, size, access, 0);
+}
 EXPORT_SYMBOL(ib_umem_get);
 
+#ifdef CONFIG_INFINIBAND_PEER_MEMORY
+struct ib_umem *ib_umem_get_peer(struct ib_device *device, unsigned long addr,
+				 size_t size, int access,
+				 unsigned long peer_mem_flags)
+{
+	return __ib_umem_get(device, addr, size, access,
+			     IB_PEER_MEM_ALLOW | peer_mem_flags);
+}
+EXPORT_SYMBOL(ib_umem_get_peer);
+#endif
+
 /**
  * ib_umem_release - release memory pinned with ib_umem_get
  * @umem: umem struct to release
@@ -272,6 +315,10 @@ void ib_umem_release(struct ib_umem *umem)
 	if (umem->is_odp)
 		return ib_umem_odp_release(to_ib_umem_odp(umem));
 
+#ifdef CONFIG_INFINIBAND_PEER_MEMORY
+	if (umem->is_peer)
+		return ib_peer_umem_release(umem);
+#endif
 	__ib_umem_release(umem->ibdev, umem, 1);
 
 	atomic64_sub(ib_umem_num_pages(umem), &umem->owning_mm->pinned_vm);
diff --git a/drivers/infiniband/hw/xsc/ib_umem_ex.c b/drivers/infiniband/hw/xsc/ib_umem_ex.c
index 71c823bdc0f6e6e8fa41cefcee3259d4648a0263..c60afbc0270ce8963f2b4018c9e4a9db70458ba5 100644
--- a/drivers/infiniband/hw/xsc/ib_umem_ex.c
+++ b/drivers/infiniband/hw/xsc/ib_umem_ex.c
@@ -5,11 +5,11 @@
  */
 
 #include <linux/sched/mm.h>
-
-#include "ib_peer_mem.h"
-
 #include <rdma/ib_verbs.h>
 #include "ib_umem_ex.h"
+#ifndef CONFIG_INFINIBAND_PEER_MEMORY
+#include "ib_peer_mem.h"
+#endif
 
 #if defined(IB_CORE_UMEM_EX_V1)
 #define get_mm(umem_ctx) ((umem_ctx)->mm)
@@ -88,12 +88,16 @@ struct ib_umem_ex *ib_umem_ex(struct ib_umem *umem)
 	if (!umem)
 		return ERR_PTR(-EINVAL);
 
+#ifdef CONFIG_INFINIBAND_PEER_MEMORY
+	ret_umem = (struct ib_umem_ex *)umem;
+#else
 	ret_umem =  kzalloc(sizeof(*ret_umem), GFP_KERNEL);
 	if (!ret_umem)
 		return ERR_PTR(-ENOMEM);
 
 	ret_umem->umem = *umem;
 	kfree(umem);
+#endif
 	return ret_umem;
 }
 
diff --git a/drivers/infiniband/hw/xsc/ib_umem_ex.h b/drivers/infiniband/hw/xsc/ib_umem_ex.h
index b73eecf3cd90280c120767a253299e0eb803a89b..034d1c55e5aa647a8f50a4e06b032d074e451143 100644
--- a/drivers/infiniband/hw/xsc/ib_umem_ex.h
+++ b/drivers/infiniband/hw/xsc/ib_umem_ex.h
@@ -15,14 +15,17 @@ struct invalidation_ctx;
 // ib umem ex ib_umem add peer memory support
 struct ib_umem_ex {
 	struct ib_umem umem;
+#ifndef CONFIG_INFINIBAND_PEER_MEMORY
 	struct ib_peer_memory_client *ib_peer_mem;
 	struct invalidation_ctx *invalidation_ctx;
 	void *peer_mem_client_context;
+#endif
 };
 
 // expand ib_umem to ib_umem_ex by reallocate
 struct ib_umem_ex *ib_umem_ex(struct ib_umem *umem);
 
+#ifndef CONFIG_INFINIBAND_PEER_MEMORY
 typedef void (*umem_invalidate_func_t)(void *invalidation_cookie,
 	struct ib_umem_ex *umem_ex, unsigned long addr, size_t size);
 
@@ -36,6 +39,7 @@ struct invalidation_ctx {
 	int peer_invalidated;
 	struct completion comp;
 };
+#endif
 
 struct ib_umem_ex *ib_client_umem_get(struct ib_ucontext *context,
 				      unsigned long addr, size_t size, int access,
diff --git a/drivers/infiniband/hw/xsc/mr.c b/drivers/infiniband/hw/xsc/mr.c
index 8b716392a964c8fcc5b25784bbb84c2a21a34719..013f470e0f940131b1488e388ccfb97ac1eb675a 100644
--- a/drivers/infiniband/hw/xsc/mr.c
+++ b/drivers/infiniband/hw/xsc/mr.c
@@ -14,9 +14,11 @@
 #include "ib_umem_ex.h"
 #include "xsc_ib.h"
 
+#ifndef CONFIG_INFINIBAND_PEER_MEMORY
 static void xsc_invalidate_umem(void *invalidation_cookie,
 				struct ib_umem_ex *umem,
 				unsigned long addr, size_t size);
+#endif
 
 enum {
 	DEF_CACHE_SIZE	= 10,
@@ -164,8 +166,16 @@ struct ib_mr *xsc_ib_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
 	xsc_ib_dbg(dev, "start 0x%llx, virt_addr 0x%llx, length 0x%llx\n",
 		   start, virt_addr, length);
 
+#ifdef CONFIG_INFINIBAND_PEER_MEMORY
+	umem = ib_umem_get_peer(&dev->ib_dev, start, length,
+				access_flags, IB_PEER_MEM_INVAL_SUPP);
+#else
 	umem = ib_umem_get(&dev->ib_dev, start, length, access_flags);
+#endif
 	if (IS_ERR(umem)) {
+#ifdef CONFIG_INFINIBAND_PEER_MEMORY
+		return (void *)umem;
+#else
 		// check client peer memory
 		u8 peer_exists = 0;
 
@@ -188,13 +198,17 @@ struct ib_mr *xsc_ib_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
 		if (err)
 			goto error;
 		using_peer_mem = 1;
-
+#endif
 	} else {
 		umem_ex = ib_umem_ex(umem);
 		if (IS_ERR(umem_ex)) {
 			err = -ENOMEM;
 			goto error;
 		}
+#ifdef CONFIG_INFINIBAND_PEER_MEMORY
+		if (umem->is_peer)
+			using_peer_mem = 1;
+#endif
 	}
 	umem = &umem_ex->umem;
 
@@ -294,6 +308,7 @@ xsc_ib_dereg_mr_def()
 	return 0;
 }
 
+#ifndef CONFIG_INFINIBAND_PEER_MEMORY
 static void xsc_invalidate_umem(void *invalidation_cookie,
 				struct ib_umem_ex *umem,
 				unsigned long addr,
@@ -320,6 +335,7 @@ static void xsc_invalidate_umem(void *invalidation_cookie,
 	xsc_core_dereg_mr(dev->xdev, &mr->mmr);
 	complete(&mr->invalidation_comp);
 }
+#endif
 
 xsc_ib_alloc_mr_def()
 {
diff --git a/include/rdma/ib_umem.h b/include/rdma/ib_umem.h
index 70597508c7656b6dbd30626000e4521f0c04e6e1..164fa0bfacbe3432b3fdc7ff6f3cca433b9013eb 100644
--- a/include/rdma/ib_umem.h
+++ b/include/rdma/ib_umem.h
@@ -22,12 +22,26 @@ struct ib_umem {
 	unsigned long		address;
 	u32 writable : 1;
 	u32 is_odp : 1;
+#ifdef CONFIG_INFINIBAND_PEER_MEMORY
+#ifndef __GENKSYMS__
+	/* Placing at the end of the bitfield list is ABI preserving on LE */
+	u32 is_peer : 1;
+#endif
+#endif
 	struct work_struct	work;
 	struct sg_table sg_head;
 	int             nmap;
 	unsigned int    sg_nents;
 };
 
+#ifdef CONFIG_INFINIBAND_PEER_MEMORY
+typedef void (*umem_invalidate_func_t)(struct ib_umem *umem, void *priv);
+enum ib_peer_mem_flags {
+	IB_PEER_MEM_ALLOW = 1 << 0,
+	IB_PEER_MEM_INVAL_SUPP = 1 << 1,
+};
+#endif
+
 /* Returns the offset of the umem start relative to the first page. */
 static inline int ib_umem_offset(struct ib_umem *umem)
 {
@@ -79,6 +93,15 @@ int ib_umem_copy_from(void *dst, struct ib_umem *umem, size_t offset,
 unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
 				     unsigned long pgsz_bitmap,
 				     unsigned long virt);
+#ifdef CONFIG_INFINIBAND_PEER_MEMORY
+struct ib_umem *ib_umem_get_peer(struct ib_device *device, unsigned long addr,
+				 size_t size, int access,
+				 unsigned long peer_mem_flags);
+void ib_umem_activate_invalidation_notifier(struct ib_umem *umem,
+					    umem_invalidate_func_t func,
+					    void *cookie);
+void ib_umem_stop_invalidation_notifier(struct ib_umem *umem);
+#endif /* CONFIG_INFINIBAND_PEER_MEMORY */
 
 #else /* CONFIG_INFINIBAND_USER_MEM */
 
@@ -102,6 +125,26 @@ static inline unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
 	return 0;
 }
 
+#ifdef CONFIG_INFINIBAND_PEER_MEMORY
+static inline struct ib_umem *ib_umem_get_peer(struct ib_device *device,
+					       unsigned long addr, size_t size,
+					       int access,
+					       unsigned long peer_mem_flags)
+{
+	return ERR_PTR(-EINVAL);
+}
+
+static inline void ib_umem_activate_invalidation_notifier(struct ib_umem *umem,
+							  umem_invalidate_func_t func,
+							  void *cookie)
+{
+}
+
+static inline void ib_umem_stop_invalidation_notifier(struct ib_umem *umem)
+{
+}
+#endif /* CONFIG_INFINIBAND_PEER_MEMORY */
+
 #endif /* CONFIG_INFINIBAND_USER_MEM */
 
 #endif /* IB_UMEM_H */
diff --git a/include/rdma/peer_mem.h b/include/rdma/peer_mem.h
new file mode 100644
index 0000000000000000000000000000000000000000..e3dc2ca630d65727d2975ef5679ac8d6b8a247e0
--- /dev/null
+++ b/include/rdma/peer_mem.h
@@ -0,0 +1,175 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/*
+ * Copyright (c) 2014-2020,  Mellanox Technologies. All rights reserved.
+ */
+#ifndef RDMA_PEER_MEM_H
+#define RDMA_PEER_MEM_H
+
+#include <linux/scatterlist.h>
+
+#define IB_PEER_MEMORY_NAME_MAX 64
+#define IB_PEER_MEMORY_VER_MAX 16
+
+/*
+ * Prior versions used a void * for core_context, at some point this was
+ * switched to use u64. Be careful if compiling this as 32 bit. To help the
+ * value of core_context is limited to u32 so it should work OK despite the
+ * type change.
+ */
+#define PEER_MEM_U64_CORE_CONTEXT
+
+struct device;
+
+/**
+ *  struct peer_memory_client - registration information for user virtual
+ *                              memory handlers
+ *
+ * The peer_memory_client scheme allows a driver to register with the ib_umem
+ * system that it has the ability to understand user virtual address ranges
+ * that are not compatible with get_user_pages(). For instance VMAs created
+ * with io_remap_pfn_range(), or other driver special VMA.
+ *
+ * For ranges the interface understands it can provide a DMA mapped sg_table
+ * for use by the ib_umem, allowing user virtual ranges that cannot be
+ * supported by get_user_pages() to be used as umems.
+ */
+struct peer_memory_client {
+	char name[IB_PEER_MEMORY_NAME_MAX];
+	char version[IB_PEER_MEMORY_VER_MAX];
+
+	/**
+	 * acquire - Begin working with a user space virtual address range
+	 *
+	 * @addr - Virtual address to be checked whether belongs to peer.
+	 * @size - Length of the virtual memory area starting at addr.
+	 * @peer_mem_private_data - Obsolete, always NULL
+	 * @peer_mem_name - Obsolete, always NULL
+	 * @client_context - Returns an opaque value for this acquire use in
+	 *                   other APIs
+	 *
+	 * Returns 1 if the peer_memory_client supports the entire virtual
+	 * address range, 0 or -ERRNO otherwise.  If 1 is returned then
+	 * release() will be called to release the acquire().
+	 */
+	int (*acquire)(unsigned long addr, size_t size,
+		       void *peer_mem_private_data, char *peer_mem_name,
+		       void **client_context);
+	/**
+	 * get_pages - Fill in the first part of a sg_table for a virtual
+	 *             address range
+	 *
+	 * @addr - Virtual address to be checked whether belongs to peer.
+	 * @size - Length of the virtual memory area starting at addr.
+	 * @write - Always 1
+	 * @force - 1 if write is required
+	 * @sg_head - Obsolete, always NULL
+	 * @client_context - Value returned by acquire()
+	 * @core_context - Value to be passed to invalidate_peer_memory for
+	 *                 this get
+	 *
+	 * addr/size are passed as the raw virtual address range requested by
+	 * the user, it is not aligned to any page size. get_pages() is always
+	 * followed by dma_map().
+	 *
+	 * Upon return the caller can call the invalidate_callback().
+	 *
+	 * Returns 0 on success, -ERRNO on failure. After success put_pages()
+	 * will be called to return the pages.
+	 */
+	int (*get_pages)(unsigned long addr, size_t size, int write, int force,
+			 struct sg_table *sg_head, void *client_context,
+			 u64 core_context);
+	/**
+	 * dma_map - Create a DMA mapped sg_table
+	 *
+	 * @sg_head - The sg_table to allocate
+	 * @client_context - Value returned by acquire()
+	 * @dma_device - The device that will be doing DMA from these addresses
+	 * @dmasync - Obsolete, always 0
+	 * @nmap - Returns the number of dma mapped entries in the sg_head
+	 *
+	 * Must be called after get_pages(). This must fill in the sg_head with
+	 * DMA mapped SGLs for dma_device. Each SGL start and end must meet a
+	 * minimum alignment of at least PAGE_SIZE, though individual sgls can
+	 * be multiples of PAGE_SIZE, in any mixture. Since the user virtual
+	 * address/size are not page aligned, the implementation must increase
+	 * it to the logical alignment when building the SGLs.
+	 *
+	 * Returns 0 on success, -ERRNO on failure. After success dma_unmap()
+	 * will be called to unmap the pages. On failure sg_head must be left
+	 * untouched or point to a valid sg_table.
+	 */
+	int (*dma_map)(struct sg_table *sg_head, void *client_context,
+		       struct device *dma_device, int dmasync, int *nmap);
+	/**
+	 * dma_unmap - Unmap a DMA mapped sg_table
+	 *
+	 * @sg_head - The sg_table to unmap
+	 * @client_context - Value returned by acquire()
+	 * @dma_device - The device that will be doing DMA from these addresses
+	 *
+	 * sg_head will not be touched after this function returns.
+	 *
+	 * Must return 0.
+	 */
+	int (*dma_unmap)(struct sg_table *sg_head, void *client_context,
+			 struct device *dma_device);
+	/**
+	 * put_pages - Unpin a SGL
+	 *
+	 * @sg_head - The sg_table to unpin
+	 * @client_context - Value returned by acquire()
+	 *
+	 * sg_head must be freed on return.
+	 */
+	void (*put_pages)(struct sg_table *sg_head, void *client_context);
+	/* Client should always return PAGE_SIZE */
+	unsigned long (*get_page_size)(void *client_context);
+	/**
+	 * release - Undo acquire
+	 *
+	 * @client_context - Value returned by acquire()
+	 *
+	 * If acquire() returns 1 then release() must be called. All
+	 * get_pages() and dma_map()'s must be undone before calling this
+	 * function.
+	 */
+	void (*release)(void *client_context);
+};
+
+enum {
+	PEER_MEM_INVALIDATE_UNMAPS = 1 << 0,
+};
+
+struct peer_memory_client_ex {
+	struct peer_memory_client client;
+	size_t ex_size;
+	u32 flags;
+};
+
+/*
+ * If invalidate_callback() is non-NULL then the client will only support
+ * umems which can be invalidated. The caller may call the
+ * invalidate_callback() after acquire() on return the range will no longer
+ * have DMA active, and release() will have been called.
+ *
+ * Note: The implementation locking must ensure that get_pages(), and
+ * dma_map() do not have locking dependencies with invalidate_callback(). The
+ * ib_core will wait until any concurrent get_pages() or dma_map() completes
+ * before returning.
+ *
+ * Similarly, this can call dma_unmap(), put_pages() and release() from within
+ * the callback, or will wait for another thread doing those operations to
+ * complete.
+ *
+ * For these reasons the user of invalidate_callback() must be careful with
+ * locking.
+ */
+typedef int (*invalidate_peer_memory)(void *reg_handle, u64 core_context);
+
+void *
+ib_register_peer_memory_client(const struct peer_memory_client *peer_client,
+			       invalidate_peer_memory *invalidate_callback);
+void ib_unregister_peer_memory_client(void *reg_handle);
+
+#endif