mlx5: Add driver for Mellanox Connect-IB adapters

The driver is comprised of two kernel modules: mlx5_ib and mlx5_core.
This partitioning resembles what we have for mlx4, except that mlx5_ib
is the pci device driver and not mlx5_core.

mlx5_core is essentially a library that provides general functionality
that is intended to be used by other Mellanox devices that will be
introduced in the future.  mlx5_ib has a similar role as any hardware
device under drivers/infiniband/hw.

Signed-off-by: Eli Cohen <eli@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>

[ Merge in coccinelle fixes from Fengguang Wu <fengguang.wu@intel.com>.
  - Roland ]

Signed-off-by: Roland Dreier <roland@purestorage.com>
diff --git a/drivers/infiniband/hw/mlx5/mr.c b/drivers/infiniband/hw/mlx5/mr.c
new file mode 100644
index 0000000..e2daa8f
--- /dev/null
+++ b/drivers/infiniband/hw/mlx5/mr.c
@@ -0,0 +1,1007 @@
+/*
+ * Copyright (c) 2013, Mellanox Technologies inc.  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/kref.h>
+#include <linux/random.h>
+#include <linux/debugfs.h>
+#include <linux/export.h>
+#include <rdma/ib_umem.h>
+#include "mlx5_ib.h"
+
+enum {
+	DEF_CACHE_SIZE	= 10,
+};
+
+static __be64 *mr_align(__be64 *ptr, int align)
+{
+	unsigned long mask = align - 1;
+
+	return (__be64 *)(((unsigned long)ptr + mask) & ~mask);
+}
+
+static int order2idx(struct mlx5_ib_dev *dev, int order)
+{
+	struct mlx5_mr_cache *cache = &dev->cache;
+
+	if (order < cache->ent[0].order)
+		return 0;
+	else
+		return order - cache->ent[0].order;
+}
+
+static int add_keys(struct mlx5_ib_dev *dev, int c, int num)
+{
+	struct device *ddev = dev->ib_dev.dma_device;
+	struct mlx5_mr_cache *cache = &dev->cache;
+	struct mlx5_cache_ent *ent = &cache->ent[c];
+	struct mlx5_create_mkey_mbox_in *in;
+	struct mlx5_ib_mr *mr;
+	int npages = 1 << ent->order;
+	int size = sizeof(u64) * npages;
+	int err = 0;
+	int i;
+
+	in = kzalloc(sizeof(*in), GFP_KERNEL);
+	if (!in)
+		return -ENOMEM;
+
+	for (i = 0; i < num; i++) {
+		mr = kzalloc(sizeof(*mr), GFP_KERNEL);
+		if (!mr) {
+			err = -ENOMEM;
+			goto out;
+		}
+		mr->order = ent->order;
+		mr->umred = 1;
+		mr->pas = kmalloc(size + 0x3f, GFP_KERNEL);
+		if (!mr->pas) {
+			kfree(mr);
+			err = -ENOMEM;
+			goto out;
+		}
+		mr->dma = dma_map_single(ddev, mr_align(mr->pas, 0x40), size,
+					 DMA_TO_DEVICE);
+		if (dma_mapping_error(ddev, mr->dma)) {
+			kfree(mr->pas);
+			kfree(mr);
+			err = -ENOMEM;
+			goto out;
+		}
+
+		in->seg.status = 1 << 6;
+		in->seg.xlt_oct_size = cpu_to_be32((npages + 1) / 2);
+		in->seg.qpn_mkey7_0 = cpu_to_be32(0xffffff << 8);
+		in->seg.flags = MLX5_ACCESS_MODE_MTT | MLX5_PERM_UMR_EN;
+		in->seg.log2_page_size = 12;
+
+		err = mlx5_core_create_mkey(&dev->mdev, &mr->mmr, in,
+					    sizeof(*in));
+		if (err) {
+			mlx5_ib_warn(dev, "create mkey failed %d\n", err);
+			dma_unmap_single(ddev, mr->dma, size, DMA_TO_DEVICE);
+			kfree(mr->pas);
+			kfree(mr);
+			goto out;
+		}
+		cache->last_add = jiffies;
+
+		spin_lock(&ent->lock);
+		list_add_tail(&mr->list, &ent->head);
+		ent->cur++;
+		ent->size++;
+		spin_unlock(&ent->lock);
+	}
+
+out:
+	kfree(in);
+	return err;
+}
+
+static void remove_keys(struct mlx5_ib_dev *dev, int c, int num)
+{
+	struct device *ddev = dev->ib_dev.dma_device;
+	struct mlx5_mr_cache *cache = &dev->cache;
+	struct mlx5_cache_ent *ent = &cache->ent[c];
+	struct mlx5_ib_mr *mr;
+	int size;
+	int err;
+	int i;
+
+	for (i = 0; i < num; i++) {
+		spin_lock(&ent->lock);
+		if (list_empty(&ent->head)) {
+			spin_unlock(&ent->lock);
+			return;
+		}
+		mr = list_first_entry(&ent->head, struct mlx5_ib_mr, list);
+		list_del(&mr->list);
+		ent->cur--;
+		ent->size--;
+		spin_unlock(&ent->lock);
+		err = mlx5_core_destroy_mkey(&dev->mdev, &mr->mmr);
+		if (err) {
+			mlx5_ib_warn(dev, "failed destroy mkey\n");
+		} else {
+			size = ALIGN(sizeof(u64) * (1 << mr->order), 0x40);
+			dma_unmap_single(ddev, mr->dma, size, DMA_TO_DEVICE);
+			kfree(mr->pas);
+			kfree(mr);
+		}
+	}
+}
+
+static ssize_t size_write(struct file *filp, const char __user *buf,
+			  size_t count, loff_t *pos)
+{
+	struct mlx5_cache_ent *ent = filp->private_data;
+	struct mlx5_ib_dev *dev = ent->dev;
+	char lbuf[20];
+	u32 var;
+	int err;
+	int c;
+
+	if (copy_from_user(lbuf, buf, sizeof(lbuf)))
+		return -EPERM;
+
+	c = order2idx(dev, ent->order);
+	lbuf[sizeof(lbuf) - 1] = 0;
+
+	if (sscanf(lbuf, "%u", &var) != 1)
+		return -EINVAL;
+
+	if (var < ent->limit)
+		return -EINVAL;
+
+	if (var > ent->size) {
+		err = add_keys(dev, c, var - ent->size);
+		if (err)
+			return err;
+	} else if (var < ent->size) {
+		remove_keys(dev, c, ent->size - var);
+	}
+
+	return count;
+}
+
+static ssize_t size_read(struct file *filp, char __user *buf, size_t count,
+			 loff_t *pos)
+{
+	struct mlx5_cache_ent *ent = filp->private_data;
+	char lbuf[20];
+	int err;
+
+	if (*pos)
+		return 0;
+
+	err = snprintf(lbuf, sizeof(lbuf), "%d\n", ent->size);
+	if (err < 0)
+		return err;
+
+	if (copy_to_user(buf, lbuf, err))
+		return -EPERM;
+
+	*pos += err;
+
+	return err;
+}
+
+static const struct file_operations size_fops = {
+	.owner	= THIS_MODULE,
+	.open	= simple_open,
+	.write	= size_write,
+	.read	= size_read,
+};
+
+static ssize_t limit_write(struct file *filp, const char __user *buf,
+			   size_t count, loff_t *pos)
+{
+	struct mlx5_cache_ent *ent = filp->private_data;
+	struct mlx5_ib_dev *dev = ent->dev;
+	char lbuf[20];
+	u32 var;
+	int err;
+	int c;
+
+	if (copy_from_user(lbuf, buf, sizeof(lbuf)))
+		return -EPERM;
+
+	c = order2idx(dev, ent->order);
+	lbuf[sizeof(lbuf) - 1] = 0;
+
+	if (sscanf(lbuf, "%u", &var) != 1)
+		return -EINVAL;
+
+	if (var > ent->size)
+		return -EINVAL;
+
+	ent->limit = var;
+
+	if (ent->cur < ent->limit) {
+		err = add_keys(dev, c, 2 * ent->limit - ent->cur);
+		if (err)
+			return err;
+	}
+
+	return count;
+}
+
+static ssize_t limit_read(struct file *filp, char __user *buf, size_t count,
+			  loff_t *pos)
+{
+	struct mlx5_cache_ent *ent = filp->private_data;
+	char lbuf[20];
+	int err;
+
+	if (*pos)
+		return 0;
+
+	err = snprintf(lbuf, sizeof(lbuf), "%d\n", ent->limit);
+	if (err < 0)
+		return err;
+
+	if (copy_to_user(buf, lbuf, err))
+		return -EPERM;
+
+	*pos += err;
+
+	return err;
+}
+
+static const struct file_operations limit_fops = {
+	.owner	= THIS_MODULE,
+	.open	= simple_open,
+	.write	= limit_write,
+	.read	= limit_read,
+};
+
+static int someone_adding(struct mlx5_mr_cache *cache)
+{
+	int i;
+
+	for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++) {
+		if (cache->ent[i].cur < cache->ent[i].limit)
+			return 1;
+	}
+
+	return 0;
+}
+
+static void __cache_work_func(struct mlx5_cache_ent *ent)
+{
+	struct mlx5_ib_dev *dev = ent->dev;
+	struct mlx5_mr_cache *cache = &dev->cache;
+	int i = order2idx(dev, ent->order);
+
+	if (cache->stopped)
+		return;
+
+	ent = &dev->cache.ent[i];
+	if (ent->cur < 2 * ent->limit) {
+		add_keys(dev, i, 1);
+		if (ent->cur < 2 * ent->limit)
+			queue_work(cache->wq, &ent->work);
+	} else if (ent->cur > 2 * ent->limit) {
+		if (!someone_adding(cache) &&
+		    time_after(jiffies, cache->last_add + 60 * HZ)) {
+			remove_keys(dev, i, 1);
+			if (ent->cur > ent->limit)
+				queue_work(cache->wq, &ent->work);
+		} else {
+			queue_delayed_work(cache->wq, &ent->dwork, 60 * HZ);
+		}
+	}
+}
+
+static void delayed_cache_work_func(struct work_struct *work)
+{
+	struct mlx5_cache_ent *ent;
+
+	ent = container_of(work, struct mlx5_cache_ent, dwork.work);
+	__cache_work_func(ent);
+}
+
+static void cache_work_func(struct work_struct *work)
+{
+	struct mlx5_cache_ent *ent;
+
+	ent = container_of(work, struct mlx5_cache_ent, work);
+	__cache_work_func(ent);
+}
+
+static struct mlx5_ib_mr *alloc_cached_mr(struct mlx5_ib_dev *dev, int order)
+{
+	struct mlx5_mr_cache *cache = &dev->cache;
+	struct mlx5_ib_mr *mr = NULL;
+	struct mlx5_cache_ent *ent;
+	int c;
+	int i;
+
+	c = order2idx(dev, order);
+	if (c < 0 || c >= MAX_MR_CACHE_ENTRIES) {
+		mlx5_ib_warn(dev, "order %d, cache index %d\n", order, c);
+		return NULL;
+	}
+
+	for (i = c; i < MAX_MR_CACHE_ENTRIES; i++) {
+		ent = &cache->ent[i];
+
+		mlx5_ib_dbg(dev, "order %d, cache index %d\n", ent->order, i);
+
+		spin_lock(&ent->lock);
+		if (!list_empty(&ent->head)) {
+			mr = list_first_entry(&ent->head, struct mlx5_ib_mr,
+					      list);
+			list_del(&mr->list);
+			ent->cur--;
+			spin_unlock(&ent->lock);
+			if (ent->cur < ent->limit)
+				queue_work(cache->wq, &ent->work);
+			break;
+		}
+		spin_unlock(&ent->lock);
+
+		queue_work(cache->wq, &ent->work);
+
+		if (mr)
+			break;
+	}
+
+	if (!mr)
+		cache->ent[c].miss++;
+
+	return mr;
+}
+
+static void free_cached_mr(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr)
+{
+	struct mlx5_mr_cache *cache = &dev->cache;
+	struct mlx5_cache_ent *ent;
+	int shrink = 0;
+	int c;
+
+	c = order2idx(dev, mr->order);
+	if (c < 0 || c >= MAX_MR_CACHE_ENTRIES) {
+		mlx5_ib_warn(dev, "order %d, cache index %d\n", mr->order, c);
+		return;
+	}
+	ent = &cache->ent[c];
+	spin_lock(&ent->lock);
+	list_add_tail(&mr->list, &ent->head);
+	ent->cur++;
+	if (ent->cur > 2 * ent->limit)
+		shrink = 1;
+	spin_unlock(&ent->lock);
+
+	if (shrink)
+		queue_work(cache->wq, &ent->work);
+}
+
+static void clean_keys(struct mlx5_ib_dev *dev, int c)
+{
+	struct device *ddev = dev->ib_dev.dma_device;
+	struct mlx5_mr_cache *cache = &dev->cache;
+	struct mlx5_cache_ent *ent = &cache->ent[c];
+	struct mlx5_ib_mr *mr;
+	int size;
+	int err;
+
+	while (1) {
+		spin_lock(&ent->lock);
+		if (list_empty(&ent->head)) {
+			spin_unlock(&ent->lock);
+			return;
+		}
+		mr = list_first_entry(&ent->head, struct mlx5_ib_mr, list);
+		list_del(&mr->list);
+		ent->cur--;
+		ent->size--;
+		spin_unlock(&ent->lock);
+		err = mlx5_core_destroy_mkey(&dev->mdev, &mr->mmr);
+		if (err) {
+			mlx5_ib_warn(dev, "failed destroy mkey\n");
+		} else {
+			size = ALIGN(sizeof(u64) * (1 << mr->order), 0x40);
+			dma_unmap_single(ddev, mr->dma, size, DMA_TO_DEVICE);
+			kfree(mr->pas);
+			kfree(mr);
+		}
+	}
+}
+
+static int mlx5_mr_cache_debugfs_init(struct mlx5_ib_dev *dev)
+{
+	struct mlx5_mr_cache *cache = &dev->cache;
+	struct mlx5_cache_ent *ent;
+	int i;
+
+	if (!mlx5_debugfs_root)
+		return 0;
+
+	cache->root = debugfs_create_dir("mr_cache", dev->mdev.priv.dbg_root);
+	if (!cache->root)
+		return -ENOMEM;
+
+	for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++) {
+		ent = &cache->ent[i];
+		sprintf(ent->name, "%d", ent->order);
+		ent->dir = debugfs_create_dir(ent->name,  cache->root);
+		if (!ent->dir)
+			return -ENOMEM;
+
+		ent->fsize = debugfs_create_file("size", 0600, ent->dir, ent,
+						 &size_fops);
+		if (!ent->fsize)
+			return -ENOMEM;
+
+		ent->flimit = debugfs_create_file("limit", 0600, ent->dir, ent,
+						  &limit_fops);
+		if (!ent->flimit)
+			return -ENOMEM;
+
+		ent->fcur = debugfs_create_u32("cur", 0400, ent->dir,
+					       &ent->cur);
+		if (!ent->fcur)
+			return -ENOMEM;
+
+		ent->fmiss = debugfs_create_u32("miss", 0600, ent->dir,
+						&ent->miss);
+		if (!ent->fmiss)
+			return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void mlx5_mr_cache_debugfs_cleanup(struct mlx5_ib_dev *dev)
+{
+	if (!mlx5_debugfs_root)
+		return;
+
+	debugfs_remove_recursive(dev->cache.root);
+}
+
+int mlx5_mr_cache_init(struct mlx5_ib_dev *dev)
+{
+	struct mlx5_mr_cache *cache = &dev->cache;
+	struct mlx5_cache_ent *ent;
+	int limit;
+	int size;
+	int err;
+	int i;
+
+	cache->wq = create_singlethread_workqueue("mkey_cache");
+	if (!cache->wq) {
+		mlx5_ib_warn(dev, "failed to create work queue\n");
+		return -ENOMEM;
+	}
+
+	for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++) {
+		INIT_LIST_HEAD(&cache->ent[i].head);
+		spin_lock_init(&cache->ent[i].lock);
+
+		ent = &cache->ent[i];
+		INIT_LIST_HEAD(&ent->head);
+		spin_lock_init(&ent->lock);
+		ent->order = i + 2;
+		ent->dev = dev;
+
+		if (dev->mdev.profile->mask & MLX5_PROF_MASK_MR_CACHE) {
+			size = dev->mdev.profile->mr_cache[i].size;
+			limit = dev->mdev.profile->mr_cache[i].limit;
+		} else {
+			size = DEF_CACHE_SIZE;
+			limit = 0;
+		}
+		INIT_WORK(&ent->work, cache_work_func);
+		INIT_DELAYED_WORK(&ent->dwork, delayed_cache_work_func);
+		ent->limit = limit;
+		queue_work(cache->wq, &ent->work);
+	}
+
+	err = mlx5_mr_cache_debugfs_init(dev);
+	if (err)
+		mlx5_ib_warn(dev, "cache debugfs failure\n");
+
+	return 0;
+}
+
+int mlx5_mr_cache_cleanup(struct mlx5_ib_dev *dev)
+{
+	int i;
+
+	dev->cache.stopped = 1;
+	destroy_workqueue(dev->cache.wq);
+
+	mlx5_mr_cache_debugfs_cleanup(dev);
+
+	for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++)
+		clean_keys(dev, i);
+
+	return 0;
+}
+
+struct ib_mr *mlx5_ib_get_dma_mr(struct ib_pd *pd, int acc)
+{
+	struct mlx5_ib_dev *dev = to_mdev(pd->device);
+	struct mlx5_core_dev *mdev = &dev->mdev;
+	struct mlx5_create_mkey_mbox_in *in;
+	struct mlx5_mkey_seg *seg;
+	struct mlx5_ib_mr *mr;
+	int err;
+
+	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
+	if (!mr)
+		return ERR_PTR(-ENOMEM);
+
+	in = kzalloc(sizeof(*in), GFP_KERNEL);
+	if (!in) {
+		err = -ENOMEM;
+		goto err_free;
+	}
+
+	seg = &in->seg;
+	seg->flags = convert_access(acc) | MLX5_ACCESS_MODE_PA;
+	seg->flags_pd = cpu_to_be32(to_mpd(pd)->pdn | MLX5_MKEY_LEN64);
+	seg->qpn_mkey7_0 = cpu_to_be32(0xffffff << 8);
+	seg->start_addr = 0;
+
+	err = mlx5_core_create_mkey(mdev, &mr->mmr, in, sizeof(*in));
+	if (err)
+		goto err_in;
+
+	kfree(in);
+	mr->ibmr.lkey = mr->mmr.key;
+	mr->ibmr.rkey = mr->mmr.key;
+	mr->umem = NULL;
+
+	return &mr->ibmr;
+
+err_in:
+	kfree(in);
+
+err_free:
+	kfree(mr);
+
+	return ERR_PTR(err);
+}
+
+static int get_octo_len(u64 addr, u64 len, int page_size)
+{
+	u64 offset;
+	int npages;
+
+	offset = addr & (page_size - 1);
+	npages = ALIGN(len + offset, page_size) >> ilog2(page_size);
+	return (npages + 1) / 2;
+}
+
+static int use_umr(int order)
+{
+	return order <= 17;
+}
+
+static void prep_umr_reg_wqe(struct ib_pd *pd, struct ib_send_wr *wr,
+			     struct ib_sge *sg, u64 dma, int n, u32 key,
+			     int page_shift, u64 virt_addr, u64 len,
+			     int access_flags)
+{
+	struct mlx5_ib_dev *dev = to_mdev(pd->device);
+	struct ib_mr *mr = dev->umrc.mr;
+
+	sg->addr = dma;
+	sg->length = ALIGN(sizeof(u64) * n, 64);
+	sg->lkey = mr->lkey;
+
+	wr->next = NULL;
+	wr->send_flags = 0;
+	wr->sg_list = sg;
+	if (n)
+		wr->num_sge = 1;
+	else
+		wr->num_sge = 0;
+
+	wr->opcode = MLX5_IB_WR_UMR;
+	wr->wr.fast_reg.page_list_len = n;
+	wr->wr.fast_reg.page_shift = page_shift;
+	wr->wr.fast_reg.rkey = key;
+	wr->wr.fast_reg.iova_start = virt_addr;
+	wr->wr.fast_reg.length = len;
+	wr->wr.fast_reg.access_flags = access_flags;
+	wr->wr.fast_reg.page_list = (struct ib_fast_reg_page_list *)pd;
+}
+
+static void prep_umr_unreg_wqe(struct mlx5_ib_dev *dev,
+			       struct ib_send_wr *wr, u32 key)
+{
+	wr->send_flags = MLX5_IB_SEND_UMR_UNREG;
+	wr->opcode = MLX5_IB_WR_UMR;
+	wr->wr.fast_reg.rkey = key;
+}
+
+void mlx5_umr_cq_handler(struct ib_cq *cq, void *cq_context)
+{
+	struct mlx5_ib_mr *mr;
+	struct ib_wc wc;
+	int err;
+
+	while (1) {
+		err = ib_poll_cq(cq, 1, &wc);
+		if (err < 0) {
+			pr_warn("poll cq error %d\n", err);
+			return;
+		}
+		if (err == 0)
+			break;
+
+		mr = (struct mlx5_ib_mr *)(unsigned long)wc.wr_id;
+		mr->status = wc.status;
+		complete(&mr->done);
+	}
+	ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
+}
+
+static struct mlx5_ib_mr *reg_umr(struct ib_pd *pd, struct ib_umem *umem,
+				  u64 virt_addr, u64 len, int npages,
+				  int page_shift, int order, int access_flags)
+{
+	struct mlx5_ib_dev *dev = to_mdev(pd->device);
+	struct umr_common *umrc = &dev->umrc;
+	struct ib_send_wr wr, *bad;
+	struct mlx5_ib_mr *mr;
+	struct ib_sge sg;
+	int err;
+	int i;
+
+	for (i = 0; i < 10; i++) {
+		mr = alloc_cached_mr(dev, order);
+		if (mr)
+			break;
+
+		err = add_keys(dev, order2idx(dev, order), 1);
+		if (err) {
+			mlx5_ib_warn(dev, "add_keys failed\n");
+			break;
+		}
+	}
+
+	if (!mr)
+		return ERR_PTR(-EAGAIN);
+
+	mlx5_ib_populate_pas(dev, umem, page_shift, mr_align(mr->pas, 0x40), 1);
+
+	memset(&wr, 0, sizeof(wr));
+	wr.wr_id = (u64)(unsigned long)mr;
+	prep_umr_reg_wqe(pd, &wr, &sg, mr->dma, npages, mr->mmr.key, page_shift, virt_addr, len, access_flags);
+
+	/* We serialize polls so one process does not kidnap another's
+	 * completion. This is not a problem since wr is completed in
+	 * around 1 usec
+	 */
+	down(&umrc->sem);
+	init_completion(&mr->done);
+	err = ib_post_send(umrc->qp, &wr, &bad);
+	if (err) {
+		mlx5_ib_warn(dev, "post send failed, err %d\n", err);
+		up(&umrc->sem);
+		goto error;
+	}
+	wait_for_completion(&mr->done);
+	up(&umrc->sem);
+
+	if (mr->status != IB_WC_SUCCESS) {
+		mlx5_ib_warn(dev, "reg umr failed\n");
+		err = -EFAULT;
+		goto error;
+	}
+
+	return mr;
+
+error:
+	free_cached_mr(dev, mr);
+	return ERR_PTR(err);
+}
+
+static struct mlx5_ib_mr *reg_create(struct ib_pd *pd, u64 virt_addr,
+				     u64 length, struct ib_umem *umem,
+				     int npages, int page_shift,
+				     int access_flags)
+{
+	struct mlx5_ib_dev *dev = to_mdev(pd->device);
+	struct mlx5_create_mkey_mbox_in *in;
+	struct mlx5_ib_mr *mr;
+	int inlen;
+	int err;
+
+	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
+	if (!mr)
+		return ERR_PTR(-ENOMEM);
+
+	inlen = sizeof(*in) + sizeof(*in->pas) * ((npages + 1) / 2) * 2;
+	in = mlx5_vzalloc(inlen);
+	if (!in) {
+		err = -ENOMEM;
+		goto err_1;
+	}
+	mlx5_ib_populate_pas(dev, umem, page_shift, in->pas, 0);
+
+	in->seg.flags = convert_access(access_flags) |
+		MLX5_ACCESS_MODE_MTT;
+	in->seg.flags_pd = cpu_to_be32(to_mpd(pd)->pdn);
+	in->seg.start_addr = cpu_to_be64(virt_addr);
+	in->seg.len = cpu_to_be64(length);
+	in->seg.bsfs_octo_size = 0;
+	in->seg.xlt_oct_size = cpu_to_be32(get_octo_len(virt_addr, length, 1 << page_shift));
+	in->seg.log2_page_size = page_shift;
+	in->seg.qpn_mkey7_0 = cpu_to_be32(0xffffff << 8);
+	in->xlat_oct_act_size = cpu_to_be32(get_octo_len(virt_addr, length, 1 << page_shift));
+	err = mlx5_core_create_mkey(&dev->mdev, &mr->mmr, in, inlen);
+	if (err) {
+		mlx5_ib_warn(dev, "create mkey failed\n");
+		goto err_2;
+	}
+	mr->umem = umem;
+	mlx5_vfree(in);
+
+	mlx5_ib_dbg(dev, "mkey = 0x%x\n", mr->mmr.key);
+
+	return mr;
+
+err_2:
+	mlx5_vfree(in);
+
+err_1:
+	kfree(mr);
+
+	return ERR_PTR(err);
+}
+
+struct ib_mr *mlx5_ib_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
+				  u64 virt_addr, int access_flags,
+				  struct ib_udata *udata)
+{
+	struct mlx5_ib_dev *dev = to_mdev(pd->device);
+	struct mlx5_ib_mr *mr = NULL;
+	struct ib_umem *umem;
+	int page_shift;
+	int npages;
+	int ncont;
+	int order;
+	int err;
+
+	mlx5_ib_dbg(dev, "start 0x%llx, virt_addr 0x%llx, length 0x%llx\n",
+		    start, virt_addr, length);
+	umem = ib_umem_get(pd->uobject->context, start, length, access_flags,
+			   0);
+	if (IS_ERR(umem)) {
+		mlx5_ib_dbg(dev, "umem get failed\n");
+		return (void *)umem;
+	}
+
+	mlx5_ib_cont_pages(umem, start, &npages, &page_shift, &ncont, &order);
+	if (!npages) {
+		mlx5_ib_warn(dev, "avoid zero region\n");
+		err = -EINVAL;
+		goto error;
+	}
+
+	mlx5_ib_dbg(dev, "npages %d, ncont %d, order %d, page_shift %d\n",
+		    npages, ncont, order, page_shift);
+
+	if (use_umr(order)) {
+		mr = reg_umr(pd, umem, virt_addr, length, ncont, page_shift,
+			     order, access_flags);
+		if (PTR_ERR(mr) == -EAGAIN) {
+			mlx5_ib_dbg(dev, "cache empty for order %d", order);
+			mr = NULL;
+		}
+	}
+
+	if (!mr)
+		mr = reg_create(pd, virt_addr, length, umem, ncont, page_shift,
+				access_flags);
+
+	if (IS_ERR(mr)) {
+		err = PTR_ERR(mr);
+		goto error;
+	}
+
+	mlx5_ib_dbg(dev, "mkey 0x%x\n", mr->mmr.key);
+
+	mr->umem = umem;
+	mr->npages = npages;
+	spin_lock(&dev->mr_lock);
+	dev->mdev.priv.reg_pages += npages;
+	spin_unlock(&dev->mr_lock);
+	mr->ibmr.lkey = mr->mmr.key;
+	mr->ibmr.rkey = mr->mmr.key;
+
+	return &mr->ibmr;
+
+error:
+	ib_umem_release(umem);
+	return ERR_PTR(err);
+}
+
+static int unreg_umr(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr)
+{
+	struct umr_common *umrc = &dev->umrc;
+	struct ib_send_wr wr, *bad;
+	int err;
+
+	memset(&wr, 0, sizeof(wr));
+	wr.wr_id = (u64)(unsigned long)mr;
+	prep_umr_unreg_wqe(dev, &wr, mr->mmr.key);
+
+	down(&umrc->sem);
+	init_completion(&mr->done);
+	err = ib_post_send(umrc->qp, &wr, &bad);
+	if (err) {
+		up(&umrc->sem);
+		mlx5_ib_dbg(dev, "err %d\n", err);
+		goto error;
+	}
+	wait_for_completion(&mr->done);
+	up(&umrc->sem);
+	if (mr->status != IB_WC_SUCCESS) {
+		mlx5_ib_warn(dev, "unreg umr failed\n");
+		err = -EFAULT;
+		goto error;
+	}
+	return 0;
+
+error:
+	return err;
+}
+
+int mlx5_ib_dereg_mr(struct ib_mr *ibmr)
+{
+	struct mlx5_ib_dev *dev = to_mdev(ibmr->device);
+	struct mlx5_ib_mr *mr = to_mmr(ibmr);
+	struct ib_umem *umem = mr->umem;
+	int npages = mr->npages;
+	int umred = mr->umred;
+	int err;
+
+	if (!umred) {
+		err = mlx5_core_destroy_mkey(&dev->mdev, &mr->mmr);
+		if (err) {
+			mlx5_ib_warn(dev, "failed to destroy mkey 0x%x (%d)\n",
+				     mr->mmr.key, err);
+			return err;
+		}
+	} else {
+		err = unreg_umr(dev, mr);
+		if (err) {
+			mlx5_ib_warn(dev, "failed unregister\n");
+			return err;
+		}
+		free_cached_mr(dev, mr);
+	}
+
+	if (umem) {
+		ib_umem_release(umem);
+		spin_lock(&dev->mr_lock);
+		dev->mdev.priv.reg_pages -= npages;
+		spin_unlock(&dev->mr_lock);
+	}
+
+	if (!umred)
+		kfree(mr);
+
+	return 0;
+}
+
+struct ib_mr *mlx5_ib_alloc_fast_reg_mr(struct ib_pd *pd,
+					int max_page_list_len)
+{
+	struct mlx5_ib_dev *dev = to_mdev(pd->device);
+	struct mlx5_create_mkey_mbox_in *in;
+	struct mlx5_ib_mr *mr;
+	int err;
+
+	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
+	if (!mr)
+		return ERR_PTR(-ENOMEM);
+
+	in = kzalloc(sizeof(*in), GFP_KERNEL);
+	if (!in) {
+		err = -ENOMEM;
+		goto err_free;
+	}
+
+	in->seg.status = 1 << 6; /* free */
+	in->seg.xlt_oct_size = cpu_to_be32((max_page_list_len + 1) / 2);
+	in->seg.qpn_mkey7_0 = cpu_to_be32(0xffffff << 8);
+	in->seg.flags = MLX5_PERM_UMR_EN | MLX5_ACCESS_MODE_MTT;
+	in->seg.flags_pd = cpu_to_be32(to_mpd(pd)->pdn);
+	/*
+	 * TBD not needed - issue 197292 */
+	in->seg.log2_page_size = PAGE_SHIFT;
+
+	err = mlx5_core_create_mkey(&dev->mdev, &mr->mmr, in, sizeof(*in));
+	kfree(in);
+	if (err)
+		goto err_free;
+
+	mr->ibmr.lkey = mr->mmr.key;
+	mr->ibmr.rkey = mr->mmr.key;
+	mr->umem = NULL;
+
+	return &mr->ibmr;
+
+err_free:
+	kfree(mr);
+	return ERR_PTR(err);
+}
+
+struct ib_fast_reg_page_list *mlx5_ib_alloc_fast_reg_page_list(struct ib_device *ibdev,
+							       int page_list_len)
+{
+	struct mlx5_ib_fast_reg_page_list *mfrpl;
+	int size = page_list_len * sizeof(u64);
+
+	mfrpl = kmalloc(sizeof(*mfrpl), GFP_KERNEL);
+	if (!mfrpl)
+		return ERR_PTR(-ENOMEM);
+
+	mfrpl->ibfrpl.page_list = kmalloc(size, GFP_KERNEL);
+	if (!mfrpl->ibfrpl.page_list)
+		goto err_free;
+
+	mfrpl->mapped_page_list = dma_alloc_coherent(ibdev->dma_device,
+						     size, &mfrpl->map,
+						     GFP_KERNEL);
+	if (!mfrpl->mapped_page_list)
+		goto err_free;
+
+	WARN_ON(mfrpl->map & 0x3f);
+
+	return &mfrpl->ibfrpl;
+
+err_free:
+	kfree(mfrpl->ibfrpl.page_list);
+	kfree(mfrpl);
+	return ERR_PTR(-ENOMEM);
+}
+
+void mlx5_ib_free_fast_reg_page_list(struct ib_fast_reg_page_list *page_list)
+{
+	struct mlx5_ib_fast_reg_page_list *mfrpl = to_mfrpl(page_list);
+	struct mlx5_ib_dev *dev = to_mdev(page_list->device);
+	int size = page_list->max_page_list_len * sizeof(u64);
+
+	dma_free_coherent(&dev->mdev.pdev->dev, size, mfrpl->mapped_page_list,
+			  mfrpl->map);
+	kfree(mfrpl->ibfrpl.page_list);
+	kfree(mfrpl);
+}