/*
 * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved.
 * Copyright (c) 2020, Intel Corporation. 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 <linux/delay.h>
#include <linux/dma-buf.h>
#include <linux/dma-resv.h>
#include <rdma/ib_umem.h>
#include <rdma/ib_umem_odp.h>
#include <rdma/ib_verbs.h>
#include "dm.h"
#include "mlx5_ib.h"

/*
 * We can't use an array for xlt_emergency_page because dma_map_single doesn't
 * work on kernel modules memory
 */
void *xlt_emergency_page;
static DEFINE_MUTEX(xlt_emergency_page_mutex);

enum {
        MAX_PENDING_REG_MR = 8,
};

#define MLX5_UMR_ALIGN 2048

static void
create_mkey_callback(int status, struct mlx5_async_work *context);
static struct mlx5_ib_mr *reg_create(struct ib_pd *pd, struct ib_umem *umem,
                                     u64 iova, int access_flags,
                                     unsigned int page_size, bool populate);

static void set_mkc_access_pd_addr_fields(void *mkc, int acc, u64 start_addr,
                                          struct ib_pd *pd)
{
        struct mlx5_ib_dev *dev = to_mdev(pd->device);
        bool ro_pci_enabled = pcie_relaxed_ordering_enabled(dev->mdev->pdev);

        MLX5_SET(mkc, mkc, a, !!(acc & IB_ACCESS_REMOTE_ATOMIC));
        MLX5_SET(mkc, mkc, rw, !!(acc & IB_ACCESS_REMOTE_WRITE));
        MLX5_SET(mkc, mkc, rr, !!(acc & IB_ACCESS_REMOTE_READ));
        MLX5_SET(mkc, mkc, lw, !!(acc & IB_ACCESS_LOCAL_WRITE));
        MLX5_SET(mkc, mkc, lr, 1);

        if (MLX5_CAP_GEN(dev->mdev, relaxed_ordering_write))
                MLX5_SET(mkc, mkc, relaxed_ordering_write,
                         (acc & IB_ACCESS_RELAXED_ORDERING) && ro_pci_enabled);
        if (MLX5_CAP_GEN(dev->mdev, relaxed_ordering_read))
                MLX5_SET(mkc, mkc, relaxed_ordering_read,
                         (acc & IB_ACCESS_RELAXED_ORDERING) && ro_pci_enabled);

        MLX5_SET(mkc, mkc, pd, to_mpd(pd)->pdn);
        MLX5_SET(mkc, mkc, qpn, 0xffffff);
        MLX5_SET64(mkc, mkc, start_addr, start_addr);
}

static void
assign_mkey_variant(struct mlx5_ib_dev *dev, struct mlx5_core_mkey *mkey,
                    u32 *in)
{
        u8 key = atomic_inc_return(&dev->mkey_var);
        void *mkc;

        mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);
        MLX5_SET(mkc, mkc, mkey_7_0, key);
        mkey->key = key;
}

static int
mlx5_ib_create_mkey(struct mlx5_ib_dev *dev, struct mlx5_core_mkey *mkey,
                    u32 *in, int inlen)
{
        assign_mkey_variant(dev, mkey, in);
        return mlx5_core_create_mkey(dev->mdev, mkey, in, inlen);
}

static int
mlx5_ib_create_mkey_cb(struct mlx5_ib_dev *dev,
                       struct mlx5_core_mkey *mkey,
                       struct mlx5_async_ctx *async_ctx,
                       u32 *in, int inlen, u32 *out, int outlen,
                       struct mlx5_async_work *context)
{
        MLX5_SET(create_mkey_in, in, opcode, MLX5_CMD_OP_CREATE_MKEY);
        assign_mkey_variant(dev, mkey, in);
        return mlx5_cmd_exec_cb(async_ctx, in, inlen, out, outlen,
                                create_mkey_callback, context);
}

static int mr_cache_max_order(struct mlx5_ib_dev *dev);
static void queue_adjust_cache_locked(struct mlx5_cache_ent *ent);

static bool umr_can_use_indirect_mkey(struct mlx5_ib_dev *dev)
{
        return !MLX5_CAP_GEN(dev->mdev, umr_indirect_mkey_disabled);
}

static int destroy_mkey(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr)
{
        WARN_ON(xa_load(&dev->odp_mkeys, mlx5_base_mkey(mr->mmkey.key)));

        return mlx5_core_destroy_mkey(dev->mdev, &mr->mmkey);
}

static void create_mkey_callback(int status, struct mlx5_async_work *context)
{
        struct mlx5_ib_mr *mr =
                container_of(context, struct mlx5_ib_mr, cb_work);
        struct mlx5_cache_ent *ent = mr->cache_ent;
        struct mlx5_ib_dev *dev = ent->dev;
        unsigned long flags;

        if (status) {
                mlx5_ib_warn(dev, "async reg mr failed. status %d\n", status);
                kfree(mr);
                spin_lock_irqsave(&ent->lock, flags);
                ent->pending--;
                WRITE_ONCE(dev->fill_delay, 1);
                spin_unlock_irqrestore(&ent->lock, flags);
                mod_timer(&dev->delay_timer, jiffies + HZ);
                return;
        }

        mr->mmkey.type = MLX5_MKEY_MR;
        mr->mmkey.key |= mlx5_idx_to_mkey(
                MLX5_GET(create_mkey_out, mr->out, mkey_index));
        init_waitqueue_head(&mr->mmkey.wait);

        WRITE_ONCE(dev->cache.last_add, jiffies);

        spin_lock_irqsave(&ent->lock, flags);
        list_add_tail(&mr->list, &ent->head);
        ent->available_mrs++;
        ent->total_mrs++;
        /* If we are doing fill_to_high_water then keep going. */
        queue_adjust_cache_locked(ent);
        ent->pending--;
        spin_unlock_irqrestore(&ent->lock, flags);
}

static struct mlx5_ib_mr *alloc_cache_mr(struct mlx5_cache_ent *ent, void *mkc)
{
        struct mlx5_ib_mr *mr;

        mr = kzalloc(sizeof(*mr), GFP_KERNEL);
        if (!mr)
                return NULL;
        mr->cache_ent = ent;

        set_mkc_access_pd_addr_fields(mkc, 0, 0, ent->dev->umrc.pd);
        MLX5_SET(mkc, mkc, free, 1);
        MLX5_SET(mkc, mkc, umr_en, 1);
        MLX5_SET(mkc, mkc, access_mode_1_0, ent->access_mode & 0x3);
        MLX5_SET(mkc, mkc, access_mode_4_2, (ent->access_mode >> 2) & 0x7);

        MLX5_SET(mkc, mkc, translations_octword_size, ent->xlt);
        MLX5_SET(mkc, mkc, log_page_size, ent->page);
        return mr;
}

/* Asynchronously schedule new MRs to be populated in the cache. */
static int add_keys(struct mlx5_cache_ent *ent, unsigned int num)
{
        size_t inlen = MLX5_ST_SZ_BYTES(create_mkey_in);
        struct mlx5_ib_mr *mr;
        void *mkc;
        u32 *in;
        int err = 0;
        int i;

        in = kzalloc(inlen, GFP_KERNEL);
        if (!in)
                return -ENOMEM;

        mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);
        for (i = 0; i < num; i++) {
                mr = alloc_cache_mr(ent, mkc);
                if (!mr) {
                        err = -ENOMEM;
                        break;
                }
                spin_lock_irq(&ent->lock);
                if (ent->pending >= MAX_PENDING_REG_MR) {
                        err = -EAGAIN;
                        spin_unlock_irq(&ent->lock);
                        kfree(mr);
                        break;
                }
                ent->pending++;
                spin_unlock_irq(&ent->lock);
                err = mlx5_ib_create_mkey_cb(ent->dev, &mr->mmkey,
                                             &ent->dev->async_ctx, in, inlen,
                                             mr->out, sizeof(mr->out),
                                             &mr->cb_work);
                if (err) {
                        spin_lock_irq(&ent->lock);
                        ent->pending--;
                        spin_unlock_irq(&ent->lock);
                        mlx5_ib_warn(ent->dev, "create mkey failed %d\n", err);
                        kfree(mr);
                        break;
                }
        }

        kfree(in);
        return err;
}

/* Synchronously create a MR in the cache */
static struct mlx5_ib_mr *create_cache_mr(struct mlx5_cache_ent *ent)
{
        size_t inlen = MLX5_ST_SZ_BYTES(create_mkey_in);
        struct mlx5_ib_mr *mr;
        void *mkc;
        u32 *in;
        int err;

        in = kzalloc(inlen, GFP_KERNEL);
        if (!in)
                return ERR_PTR(-ENOMEM);
        mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);

        mr = alloc_cache_mr(ent, mkc);
        if (!mr) {
                err = -ENOMEM;
                goto free_in;
        }

        err = mlx5_core_create_mkey(ent->dev->mdev, &mr->mmkey, in, inlen);
        if (err)
                goto free_mr;

        mr->mmkey.type = MLX5_MKEY_MR;
        WRITE_ONCE(ent->dev->cache.last_add, jiffies);
        spin_lock_irq(&ent->lock);
        ent->total_mrs++;
        spin_unlock_irq(&ent->lock);
        kfree(in);
        return mr;
free_mr:
        kfree(mr);
free_in:
        kfree(in);
        return ERR_PTR(err);
}

static void remove_cache_mr_locked(struct mlx5_cache_ent *ent)
{
        struct mlx5_ib_mr *mr;

        lockdep_assert_held(&ent->lock);
        if (list_empty(&ent->head))
                return;
        mr = list_first_entry(&ent->head, struct mlx5_ib_mr, list);
        list_del(&mr->list);
        ent->available_mrs--;
        ent->total_mrs--;
        spin_unlock_irq(&ent->lock);
        mlx5_core_destroy_mkey(ent->dev->mdev, &mr->mmkey);
        kfree(mr);
        spin_lock_irq(&ent->lock);
}

static int resize_available_mrs(struct mlx5_cache_ent *ent, unsigned int target,
                                bool limit_fill)
{
        int err;

        lockdep_assert_held(&ent->lock);

        while (true) {
                if (limit_fill)
                        target = ent->limit * 2;
                if (target == ent->available_mrs + ent->pending)
                        return 0;
                if (target > ent->available_mrs + ent->pending) {
                        u32 todo = target - (ent->available_mrs + ent->pending);

                        spin_unlock_irq(&ent->lock);
                        err = add_keys(ent, todo);
                        if (err == -EAGAIN)
                                usleep_range(3000, 5000);
                        spin_lock_irq(&ent->lock);
                        if (err) {
                                if (err != -EAGAIN)
                                        return err;
                        } else
                                return 0;
                } else {
                        remove_cache_mr_locked(ent);
                }
        }
}

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;
        u32 target;
        int err;

        err = kstrtou32_from_user(buf, count, 0, &target);
        if (err)
                return err;

        /*
         * Target is the new value of total_mrs the user requests, however we
         * cannot free MRs that are in use. Compute the target value for
         * available_mrs.
         */
        spin_lock_irq(&ent->lock);
        if (target < ent->total_mrs - ent->available_mrs) {
                err = -EINVAL;
                goto err_unlock;
        }
        target = target - (ent->total_mrs - ent->available_mrs);
        if (target < ent->limit || target > ent->limit*2) {
                err = -EINVAL;
                goto err_unlock;
        }
        err = resize_available_mrs(ent, target, false);
        if (err)
                goto err_unlock;
        spin_unlock_irq(&ent->lock);

        return count;

err_unlock:
        spin_unlock_irq(&ent->lock);
        return err;
}

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;

        err = snprintf(lbuf, sizeof(lbuf), "%d\n", ent->total_mrs);
        if (err < 0)
                return err;

        return simple_read_from_buffer(buf, count, pos, lbuf, 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;
        u32 var;
        int err;

        err = kstrtou32_from_user(buf, count, 0, &var);
        if (err)
                return err;

        /*
         * Upon set we immediately fill the cache to high water mark implied by
         * the limit.
         */
        spin_lock_irq(&ent->lock);
        ent->limit = var;
        err = resize_available_mrs(ent, 0, true);
        spin_unlock_irq(&ent->lock);
        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;

        err = snprintf(lbuf, sizeof(lbuf), "%d\n", ent->limit);
        if (err < 0)
                return err;

        return simple_read_from_buffer(buf, count, pos, lbuf, err);
}

static const struct file_operations limit_fops = {
        .owner  = THIS_MODULE,
        .open   = simple_open,
        .write  = limit_write,
        .read   = limit_read,
};

static bool someone_adding(struct mlx5_mr_cache *cache)
{
        unsigned int i;

        for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++) {
                struct mlx5_cache_ent *ent = &cache->ent[i];
                bool ret;

                spin_lock_irq(&ent->lock);
                ret = ent->available_mrs < ent->limit;
                spin_unlock_irq(&ent->lock);
                if (ret)
                        return true;
        }
        return false;
}

/*
 * Check if the bucket is outside the high/low water mark and schedule an async
 * update. The cache refill has hysteresis, once the low water mark is hit it is
 * refilled up to the high mark.
 */
static void queue_adjust_cache_locked(struct mlx5_cache_ent *ent)
{
        lockdep_assert_held(&ent->lock);

        if (ent->disabled || READ_ONCE(ent->dev->fill_delay))
                return;
        if (ent->available_mrs < ent->limit) {
                ent->fill_to_high_water = true;
                queue_work(ent->dev->cache.wq, &ent->work);
        } else if (ent->fill_to_high_water &&
                   ent->available_mrs + ent->pending < 2 * ent->limit) {
                /*
                 * Once we start populating due to hitting a low water mark
                 * continue until we pass the high water mark.
                 */
                queue_work(ent->dev->cache.wq, &ent->work);
        } else if (ent->available_mrs == 2 * ent->limit) {
                ent->fill_to_high_water = false;
        } else if (ent->available_mrs > 2 * ent->limit) {
                /* Queue deletion of excess entries */
                ent->fill_to_high_water = false;
                if (ent->pending)
                        queue_delayed_work(ent->dev->cache.wq, &ent->dwork,
                                           msecs_to_jiffies(1000));
                else
                        queue_work(ent->dev->cache.wq, &ent->work);
        }
}

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 err;

        spin_lock_irq(&ent->lock);
        if (ent->disabled)
                goto out;

        if (ent->fill_to_high_water &&
            ent->available_mrs + ent->pending < 2 * ent->limit &&
            !READ_ONCE(dev->fill_delay)) {
                spin_unlock_irq(&ent->lock);
                err = add_keys(ent, 1);
                spin_lock_irq(&ent->lock);
                if (ent->disabled)
                        goto out;
                if (err) {
                        /*
                         * EAGAIN only happens if pending is positive, so we
                         * will be rescheduled from reg_mr_callback(). The only
                         * failure path here is ENOMEM.
                         */
                        if (err != -EAGAIN) {
                                mlx5_ib_warn(
                                        dev,
                                        "command failed order %d, err %d\n",
                                        ent->order, err);
                                queue_delayed_work(cache->wq, &ent->dwork,
                                                   msecs_to_jiffies(1000));
                        }
                }
        } else if (ent->available_mrs > 2 * ent->limit) {
                bool need_delay;

                /*
                 * The remove_cache_mr() logic is performed as garbage
                 * collection task. Such task is intended to be run when no
                 * other active processes are running.
                 *
                 * The need_resched() will return TRUE if there are user tasks
                 * to be activated in near future.
                 *
                 * In such case, we don't execute remove_cache_mr() and postpone
                 * the garbage collection work to try to run in next cycle, in
                 * order to free CPU resources to other tasks.
                 */
                spin_unlock_irq(&ent->lock);
                need_delay = need_resched() || someone_adding(cache) ||
                             !time_after(jiffies,
                                         READ_ONCE(cache->last_add) + 300 * HZ);
                spin_lock_irq(&ent->lock);
                if (ent->disabled)
                        goto out;
                if (need_delay)
                        queue_delayed_work(cache->wq, &ent->dwork, 300 * HZ);
                remove_cache_mr_locked(ent);
                queue_adjust_cache_locked(ent);
        }
out:
        spin_unlock_irq(&ent->lock);
}

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);
}

/* Allocate a special entry from the cache */
struct mlx5_ib_mr *mlx5_mr_cache_alloc(struct mlx5_ib_dev *dev,
                                       unsigned int entry, int access_flags)
{
        struct mlx5_mr_cache *cache = &dev->cache;
        struct mlx5_cache_ent *ent;
        struct mlx5_ib_mr *mr;

        if (WARN_ON(entry <= MR_CACHE_LAST_STD_ENTRY ||
                    entry >= ARRAY_SIZE(cache->ent)))
                return ERR_PTR(-EINVAL);

        /* Matches access in alloc_cache_mr() */
        if (!mlx5_ib_can_reconfig_with_umr(dev, 0, access_flags))
                return ERR_PTR(-EOPNOTSUPP);

        ent = &cache->ent[entry];
        spin_lock_irq(&ent->lock);
        if (list_empty(&ent->head)) {
                spin_unlock_irq(&ent->lock);
                mr = create_cache_mr(ent);
                if (IS_ERR(mr))
                        return mr;
        } else {
                mr = list_first_entry(&ent->head, struct mlx5_ib_mr, list);
                list_del(&mr->list);
                ent->available_mrs--;
                queue_adjust_cache_locked(ent);
                spin_unlock_irq(&ent->lock);

                mlx5_clear_mr(mr);
        }
        mr->access_flags = access_flags;
        return mr;
}

/* Return a MR already available in the cache */
static struct mlx5_ib_mr *get_cache_mr(struct mlx5_cache_ent *req_ent)
{
        struct mlx5_ib_dev *dev = req_ent->dev;
        struct mlx5_ib_mr *mr = NULL;
        struct mlx5_cache_ent *ent = req_ent;

        /* Try larger MR pools from the cache to satisfy the allocation */
        for (; ent != &dev->cache.ent[MR_CACHE_LAST_STD_ENTRY + 1]; ent++) {
                mlx5_ib_dbg(dev, "order %u, cache index %zu\n", ent->order,
                            ent - dev->cache.ent);

                spin_lock_irq(&ent->lock);
                if (!list_empty(&ent->head)) {
                        mr = list_first_entry(&ent->head, struct mlx5_ib_mr,
                                              list);
                        list_del(&mr->list);
                        ent->available_mrs--;
                        queue_adjust_cache_locked(ent);
                        spin_unlock_irq(&ent->lock);
                        mlx5_clear_mr(mr);
                        return mr;
                }
                queue_adjust_cache_locked(ent);
                spin_unlock_irq(&ent->lock);
        }
        req_ent->miss++;
        return NULL;
}

static void mlx5_mr_cache_free(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr)
{
        struct mlx5_cache_ent *ent = mr->cache_ent;

        spin_lock_irq(&ent->lock);
        list_add_tail(&mr->list, &ent->head);
        ent->available_mrs++;
        queue_adjust_cache_locked(ent);
        spin_unlock_irq(&ent->lock);
}

static void clean_keys(struct mlx5_ib_dev *dev, int c)
{
        struct mlx5_mr_cache *cache = &dev->cache;
        struct mlx5_cache_ent *ent = &cache->ent[c];
        struct mlx5_ib_mr *tmp_mr;
        struct mlx5_ib_mr *mr;
        LIST_HEAD(del_list);

        cancel_delayed_work(&ent->dwork);
        while (1) {
                spin_lock_irq(&ent->lock);
                if (list_empty(&ent->head)) {
                        spin_unlock_irq(&ent->lock);
                        break;
                }
                mr = list_first_entry(&ent->head, struct mlx5_ib_mr, list);
                list_move(&mr->list, &del_list);
                ent->available_mrs--;
                ent->total_mrs--;
                spin_unlock_irq(&ent->lock);
                mlx5_core_destroy_mkey(dev->mdev, &mr->mmkey);
        }

        list_for_each_entry_safe(mr, tmp_mr, &del_list, list) {
                list_del(&mr->list);
                kfree(mr);
        }
}

static void mlx5_mr_cache_debugfs_cleanup(struct mlx5_ib_dev *dev)
{
        if (!mlx5_debugfs_root || dev->is_rep)
                return;

        debugfs_remove_recursive(dev->cache.root);
        dev->cache.root = NULL;
}

static void mlx5_mr_cache_debugfs_init(struct mlx5_ib_dev *dev)
{
        struct mlx5_mr_cache *cache = &dev->cache;
        struct mlx5_cache_ent *ent;
        struct dentry *dir;
        int i;

        if (!mlx5_debugfs_root || dev->is_rep)
                return;

        cache->root = debugfs_create_dir("mr_cache", dev->mdev->priv.dbg_root);

        for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++) {
                ent = &cache->ent[i];
                sprintf(ent->name, "%d", ent->order);
                dir = debugfs_create_dir(ent->name, cache->root);
                debugfs_create_file("size", 0600, dir, ent, &size_fops);
                debugfs_create_file("limit", 0600, dir, ent, &limit_fops);
                debugfs_create_u32("cur", 0400, dir, &ent->available_mrs);
                debugfs_create_u32("miss", 0600, dir, &ent->miss);
        }
}

static void delay_time_func(struct timer_list *t)
{
        struct mlx5_ib_dev *dev = from_timer(dev, t, delay_timer);

        WRITE_ONCE(dev->fill_delay, 0);
}

int mlx5_mr_cache_init(struct mlx5_ib_dev *dev)
{
        struct mlx5_mr_cache *cache = &dev->cache;
        struct mlx5_cache_ent *ent;
        int i;

        mutex_init(&dev->slow_path_mutex);
        cache->wq = alloc_ordered_workqueue("mkey_cache", WQ_MEM_RECLAIM);
        if (!cache->wq) {
                mlx5_ib_warn(dev, "failed to create work queue\n");
                return -ENOMEM;
        }

        mlx5_cmd_init_async_ctx(dev->mdev, &dev->async_ctx);
        timer_setup(&dev->delay_timer, delay_time_func, 0);
        for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++) {
                ent = &cache->ent[i];
                INIT_LIST_HEAD(&ent->head);
                spin_lock_init(&ent->lock);
                ent->order = i + 2;
                ent->dev = dev;
                ent->limit = 0;

                INIT_WORK(&ent->work, cache_work_func);
                INIT_DELAYED_WORK(&ent->dwork, delayed_cache_work_func);

                if (i > MR_CACHE_LAST_STD_ENTRY) {
                        mlx5_odp_init_mr_cache_entry(ent);
                        continue;
                }

                if (ent->order > mr_cache_max_order(dev))
                        continue;

                ent->page = PAGE_SHIFT;
                ent->xlt = (1 << ent->order) * sizeof(struct mlx5_mtt) /
                           MLX5_IB_UMR_OCTOWORD;
                ent->access_mode = MLX5_MKC_ACCESS_MODE_MTT;
                if ((dev->mdev->profile.mask & MLX5_PROF_MASK_MR_CACHE) &&
                    !dev->is_rep && mlx5_core_is_pf(dev->mdev) &&
                    mlx5_ib_can_load_pas_with_umr(dev, 0))
                        ent->limit = dev->mdev->profile.mr_cache[i].limit;
                else
                        ent->limit = 0;
                spin_lock_irq(&ent->lock);
                queue_adjust_cache_locked(ent);
                spin_unlock_irq(&ent->lock);
        }

        mlx5_mr_cache_debugfs_init(dev);

        return 0;
}

int mlx5_mr_cache_cleanup(struct mlx5_ib_dev *dev)
{
        unsigned int i;

        if (!dev->cache.wq)
                return 0;

        for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++) {
                struct mlx5_cache_ent *ent = &dev->cache.ent[i];

                spin_lock_irq(&ent->lock);
                ent->disabled = true;
                spin_unlock_irq(&ent->lock);
                cancel_work_sync(&ent->work);
                cancel_delayed_work_sync(&ent->dwork);
        }

        mlx5_mr_cache_debugfs_cleanup(dev);
        mlx5_cmd_cleanup_async_ctx(&dev->async_ctx);

        for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++)
                clean_keys(dev, i);

        destroy_workqueue(dev->cache.wq);
        del_timer_sync(&dev->delay_timer);

        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);
        int inlen = MLX5_ST_SZ_BYTES(create_mkey_in);
        struct mlx5_ib_mr *mr;
        void *mkc;
        u32 *in;
        int err;

        mr = kzalloc(sizeof(*mr), GFP_KERNEL);
        if (!mr)
                return ERR_PTR(-ENOMEM);

        in = kzalloc(inlen, GFP_KERNEL);
        if (!in) {
                err = -ENOMEM;
                goto err_free;
        }

        mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);

        MLX5_SET(mkc, mkc, access_mode_1_0, MLX5_MKC_ACCESS_MODE_PA);
        MLX5_SET(mkc, mkc, length64, 1);
        set_mkc_access_pd_addr_fields(mkc, acc | IB_ACCESS_RELAXED_ORDERING, 0,
                                      pd);

        err = mlx5_ib_create_mkey(dev, &mr->mmkey, in, inlen);
        if (err)
                goto err_in;

        kfree(in);
        mr->mmkey.type = MLX5_MKEY_MR;
        mr->ibmr.lkey = mr->mmkey.key;
        mr->ibmr.rkey = mr->mmkey.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_shift)
{
        u64 page_size = 1ULL << page_shift;
        u64 offset;
        int npages;

        offset = addr & (page_size - 1);
        npages = ALIGN(len + offset, page_size) >> page_shift;
        return (npages + 1) / 2;
}

static int mr_cache_max_order(struct mlx5_ib_dev *dev)
{
        if (MLX5_CAP_GEN(dev->mdev, umr_extended_translation_offset))
                return MR_CACHE_LAST_STD_ENTRY + 2;
        return MLX5_MAX_UMR_SHIFT;
}

static void mlx5_ib_umr_done(struct ib_cq *cq, struct ib_wc *wc)
{
        struct mlx5_ib_umr_context *context =
                container_of(wc->wr_cqe, struct mlx5_ib_umr_context, cqe);

        context->status = wc->status;
        complete(&context->done);
}

static inline void mlx5_ib_init_umr_context(struct mlx5_ib_umr_context *context)
{
        context->cqe.done = mlx5_ib_umr_done;
        context->status = -1;
        init_completion(&context->done);
}

static int mlx5_ib_post_send_wait(struct mlx5_ib_dev *dev,
                                  struct mlx5_umr_wr *umrwr)
{
        struct umr_common *umrc = &dev->umrc;
        const struct ib_send_wr *bad;
        int err;
        struct mlx5_ib_umr_context umr_context;

        mlx5_ib_init_umr_context(&umr_context);
        umrwr->wr.wr_cqe = &umr_context.cqe;

        down(&umrc->sem);
        err = ib_post_send(umrc->qp, &umrwr->wr, &bad);
        if (err) {
                mlx5_ib_warn(dev, "UMR post send failed, err %d\n", err);
        } else {
                wait_for_completion(&umr_context.done);
                if (umr_context.status != IB_WC_SUCCESS) {
                        mlx5_ib_warn(dev, "reg umr failed (%u)\n",
                                     umr_context.status);
                        err = -EFAULT;
                }
        }
        up(&umrc->sem);
        return err;
}

static struct mlx5_cache_ent *mr_cache_ent_from_order(struct mlx5_ib_dev *dev,
                                                      unsigned int order)
{
        struct mlx5_mr_cache *cache = &dev->cache;

        if (order < cache->ent[0].order)
                return &cache->ent[0];
        order = order - cache->ent[0].order;
        if (order > MR_CACHE_LAST_STD_ENTRY)
                return NULL;
        return &cache->ent[order];
}

static void set_mr_fields(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr,
                          u64 length, int access_flags)
{
        mr->ibmr.lkey = mr->mmkey.key;
        mr->ibmr.rkey = mr->mmkey.key;
        mr->ibmr.length = length;
        mr->ibmr.device = &dev->ib_dev;
        mr->access_flags = access_flags;
}

static unsigned int mlx5_umem_dmabuf_default_pgsz(struct ib_umem *umem,
                                                  u64 iova)
{
        /*
         * The alignment of iova has already been checked upon entering
         * UVERBS_METHOD_REG_DMABUF_MR
         */
        umem->iova = iova;
        return PAGE_SIZE;
}

static struct mlx5_ib_mr *alloc_cacheable_mr(struct ib_pd *pd,
                                             struct ib_umem *umem, u64 iova,
                                             int access_flags)
{
        struct mlx5_ib_dev *dev = to_mdev(pd->device);
        struct mlx5_cache_ent *ent;
        struct mlx5_ib_mr *mr;
        unsigned int page_size;

        if (umem->is_dmabuf)
                page_size = mlx5_umem_dmabuf_default_pgsz(umem, iova);
        else
                page_size = mlx5_umem_find_best_pgsz(umem, mkc, log_page_size,
                                                     0, iova);
        if (WARN_ON(!page_size))
                return ERR_PTR(-EINVAL);
        ent = mr_cache_ent_from_order(
                dev, order_base_2(ib_umem_num_dma_blocks(umem, page_size)));
        /*
         * Matches access in alloc_cache_mr(). If the MR can't come from the
         * cache then synchronously create an uncached one.
         */
        if (!ent || ent->limit == 0 ||
            !mlx5_ib_can_reconfig_with_umr(dev, 0, access_flags)) {
                mutex_lock(&dev->slow_path_mutex);
                mr = reg_create(pd, umem, iova, access_flags, page_size, false);
                mutex_unlock(&dev->slow_path_mutex);
                return mr;
        }

        mr = get_cache_mr(ent);
        if (!mr) {
                mr = create_cache_mr(ent);
                /*
                 * The above already tried to do the same stuff as reg_create(),
                 * no reason to try it again.
                 */
                if (IS_ERR(mr))
                        return mr;
        }

        mr->ibmr.pd = pd;
        mr->umem = umem;
        mr->mmkey.iova = iova;
        mr->mmkey.size = umem->length;
        mr->mmkey.pd = to_mpd(pd)->pdn;
        mr->page_shift = order_base_2(page_size);
        set_mr_fields(dev, mr, umem->length, access_flags);

        return mr;
}

#define MLX5_MAX_UMR_CHUNK ((1 << (MLX5_MAX_UMR_SHIFT + 4)) - \
                            MLX5_UMR_MTT_ALIGNMENT)
#define MLX5_SPARE_UMR_CHUNK 0x10000

/*
 * Allocate a temporary buffer to hold the per-page information to transfer to
 * HW. For efficiency this should be as large as it can be, but buffer
 * allocation failure is not allowed, so try smaller sizes.
 */
static void *mlx5_ib_alloc_xlt(size_t *nents, size_t ent_size, gfp_t gfp_mask)
{
        const size_t xlt_chunk_align =
                MLX5_UMR_MTT_ALIGNMENT / ent_size;
        size_t size;
        void *res = NULL;

        static_assert(PAGE_SIZE % MLX5_UMR_MTT_ALIGNMENT == 0);

        /*
         * MLX5_IB_UPD_XLT_ATOMIC doesn't signal an atomic context just that the
         * allocation can't trigger any kind of reclaim.
         */
        might_sleep();

        gfp_mask |= __GFP_ZERO | __GFP_NORETRY;

        /*
         * If the system already has a suitable high order page then just use
         * that, but don't try hard to create one. This max is about 1M, so a
         * free x86 huge page will satisfy it.
         */
        size = min_t(size_t, ent_size * ALIGN(*nents, xlt_chunk_align),
                     MLX5_MAX_UMR_CHUNK);
        *nents = size / ent_size;
        res = (void *)__get_free_pages(gfp_mask | __GFP_NOWARN,
                                       get_order(size));
        if (res)
                return res;

        if (size > MLX5_SPARE_UMR_CHUNK) {
                size = MLX5_SPARE_UMR_CHUNK;
                *nents = size / ent_size;
                res = (void *)__get_free_pages(gfp_mask | __GFP_NOWARN,
                                               get_order(size));
                if (res)
                        return res;
        }

        *nents = PAGE_SIZE / ent_size;
        res = (void *)__get_free_page(gfp_mask);
        if (res)
                return res;

        mutex_lock(&xlt_emergency_page_mutex);
        memset(xlt_emergency_page, 0, PAGE_SIZE);
        return xlt_emergency_page;
}

static void mlx5_ib_free_xlt(void *xlt, size_t length)
{
        if (xlt == xlt_emergency_page) {
                mutex_unlock(&xlt_emergency_page_mutex);
                return;
        }

        free_pages((unsigned long)xlt, get_order(length));
}

/*
 * Create a MLX5_IB_SEND_UMR_UPDATE_XLT work request and XLT buffer ready for
 * submission.
 */
static void *mlx5_ib_create_xlt_wr(struct mlx5_ib_mr *mr,
                                   struct mlx5_umr_wr *wr, struct ib_sge *sg,
                                   size_t nents, size_t ent_size,
                                   unsigned int flags)
{
        struct mlx5_ib_dev *dev = mr_to_mdev(mr);
        struct device *ddev = &dev->mdev->pdev->dev;
        dma_addr_t dma;
        void *xlt;

        xlt = mlx5_ib_alloc_xlt(&nents, ent_size,
                                flags & MLX5_IB_UPD_XLT_ATOMIC ? GFP_ATOMIC :
                                                                 GFP_KERNEL);
        sg->length = nents * ent_size;
        dma = dma_map_single(ddev, xlt, sg->length, DMA_TO_DEVICE);
        if (dma_mapping_error(ddev, dma)) {
                mlx5_ib_err(dev, "unable to map DMA during XLT update.\n");
                mlx5_ib_free_xlt(xlt, sg->length);
                return NULL;
        }
        sg->addr = dma;
        sg->lkey = dev->umrc.pd->local_dma_lkey;

        memset(wr, 0, sizeof(*wr));
        wr->wr.send_flags = MLX5_IB_SEND_UMR_UPDATE_XLT;
        if (!(flags & MLX5_IB_UPD_XLT_ENABLE))
                wr->wr.send_flags |= MLX5_IB_SEND_UMR_FAIL_IF_FREE;
        wr->wr.sg_list = sg;
        wr->wr.num_sge = 1;
        wr->wr.opcode = MLX5_IB_WR_UMR;
        wr->pd = mr->ibmr.pd;
        wr->mkey = mr->mmkey.key;
        wr->length = mr->mmkey.size;
        wr->virt_addr = mr->mmkey.iova;
        wr->access_flags = mr->access_flags;
        wr->page_shift = mr->page_shift;
        wr->xlt_size = sg->length;
        return xlt;
}

static void mlx5_ib_unmap_free_xlt(struct mlx5_ib_dev *dev, void *xlt,
                                   struct ib_sge *sg)
{
        struct device *ddev = &dev->mdev->pdev->dev;

        dma_unmap_single(ddev, sg->addr, sg->length, DMA_TO_DEVICE);
        mlx5_ib_free_xlt(xlt, sg->length);
}

static unsigned int xlt_wr_final_send_flags(unsigned int flags)
{
        unsigned int res = 0;

        if (flags & MLX5_IB_UPD_XLT_ENABLE)
                res |= MLX5_IB_SEND_UMR_ENABLE_MR |
                       MLX5_IB_SEND_UMR_UPDATE_PD_ACCESS |
                       MLX5_IB_SEND_UMR_UPDATE_TRANSLATION;
        if (flags & MLX5_IB_UPD_XLT_PD || flags & MLX5_IB_UPD_XLT_ACCESS)
                res |= MLX5_IB_SEND_UMR_UPDATE_PD_ACCESS;
        if (flags & MLX5_IB_UPD_XLT_ADDR)
                res |= MLX5_IB_SEND_UMR_UPDATE_TRANSLATION;
        return res;
}

int mlx5_ib_update_xlt(struct mlx5_ib_mr *mr, u64 idx, int npages,
                       int page_shift, int flags)
{
        struct mlx5_ib_dev *dev = mr_to_mdev(mr);
        struct device *ddev = &dev->mdev->pdev->dev;
        void *xlt;
        struct mlx5_umr_wr wr;
        struct ib_sge sg;
        int err = 0;
        int desc_size = (flags & MLX5_IB_UPD_XLT_INDIRECT)
                               ? sizeof(struct mlx5_klm)
                               : sizeof(struct mlx5_mtt);
        const int page_align = MLX5_UMR_MTT_ALIGNMENT / desc_size;
        const int page_mask = page_align - 1;
        size_t pages_mapped = 0;
        size_t pages_to_map = 0;
        size_t pages_iter;
        size_t size_to_map = 0;
        size_t orig_sg_length;

        if ((flags & MLX5_IB_UPD_XLT_INDIRECT) &&
            !umr_can_use_indirect_mkey(dev))
                return -EPERM;

        if (WARN_ON(!mr->umem->is_odp))
                return -EINVAL;

        /* UMR copies MTTs in units of MLX5_UMR_MTT_ALIGNMENT bytes,
         * so we need to align the offset and length accordingly
         */
        if (idx & page_mask) {
                npages += idx & page_mask;
                idx &= ~page_mask;
        }
        pages_to_map = ALIGN(npages, page_align);

        xlt = mlx5_ib_create_xlt_wr(mr, &wr, &sg, npages, desc_size, flags);
        if (!xlt)
                return -ENOMEM;
        pages_iter = sg.length / desc_size;
        orig_sg_length = sg.length;

        if (!(flags & MLX5_IB_UPD_XLT_INDIRECT)) {
                struct ib_umem_odp *odp = to_ib_umem_odp(mr->umem);
                size_t max_pages = ib_umem_odp_num_pages(odp) - idx;

                pages_to_map = min_t(size_t, pages_to_map, max_pages);
        }

        wr.page_shift = page_shift;

        for (pages_mapped = 0;
             pages_mapped < pages_to_map && !err;
             pages_mapped += pages_iter, idx += pages_iter) {
                npages = min_t(int, pages_iter, pages_to_map - pages_mapped);
                size_to_map = npages * desc_size;
                dma_sync_single_for_cpu(ddev, sg.addr, sg.length,
                                        DMA_TO_DEVICE);
                mlx5_odp_populate_xlt(xlt, idx, npages, mr, flags);
                dma_sync_single_for_device(ddev, sg.addr, sg.length,
                                           DMA_TO_DEVICE);

                sg.length = ALIGN(size_to_map, MLX5_UMR_MTT_ALIGNMENT);

                if (pages_mapped + pages_iter >= pages_to_map)
                        wr.wr.send_flags |= xlt_wr_final_send_flags(flags);

                wr.offset = idx * desc_size;
                wr.xlt_size = sg.length;

                err = mlx5_ib_post_send_wait(dev, &wr);
        }
        sg.length = orig_sg_length;
        mlx5_ib_unmap_free_xlt(dev, xlt, &sg);
        return err;
}

/*
 * Send the DMA list to the HW for a normal MR using UMR.
 * Dmabuf MR is handled in a similar way, except that the MLX5_IB_UPD_XLT_ZAP
 * flag may be used.
 */
int mlx5_ib_update_mr_pas(struct mlx5_ib_mr *mr, unsigned int flags)
{
        struct mlx5_ib_dev *dev = mr_to_mdev(mr);
        struct device *ddev = &dev->mdev->pdev->dev;
        struct ib_block_iter biter;
        struct mlx5_mtt *cur_mtt;
        struct mlx5_umr_wr wr;
        size_t orig_sg_length;
        struct mlx5_mtt *mtt;
        size_t final_size;
        struct ib_sge sg;
        int err = 0;

        if (WARN_ON(mr->umem->is_odp))
                return -EINVAL;

        mtt = mlx5_ib_create_xlt_wr(mr, &wr, &sg,
                                    ib_umem_num_dma_blocks(mr->umem,
                                                           1 << mr->page_shift),
                                    sizeof(*mtt), flags);
        if (!mtt)
                return -ENOMEM;
        orig_sg_length = sg.length;

        cur_mtt = mtt;
        rdma_for_each_block (mr->umem->sgt_append.sgt.sgl, &biter,
                             mr->umem->sgt_append.sgt.nents,
                             BIT(mr->page_shift)) {
                if (cur_mtt == (void *)mtt + sg.length) {
                        dma_sync_single_for_device(ddev, sg.addr, sg.length,
                                                   DMA_TO_DEVICE);
                        err = mlx5_ib_post_send_wait(dev, &wr);
                        if (err)
                                goto err;
                        dma_sync_single_for_cpu(ddev, sg.addr, sg.length,
                                                DMA_TO_DEVICE);
                        wr.offset += sg.length;
                        cur_mtt = mtt;
                }

                cur_mtt->ptag =
                        cpu_to_be64(rdma_block_iter_dma_address(&biter) |
                                    MLX5_IB_MTT_PRESENT);

                if (mr->umem->is_dmabuf && (flags & MLX5_IB_UPD_XLT_ZAP))
                        cur_mtt->ptag = 0;

                cur_mtt++;
        }

        final_size = (void *)cur_mtt - (void *)mtt;
        sg.length = ALIGN(final_size, MLX5_UMR_MTT_ALIGNMENT);
        memset(cur_mtt, 0, sg.length - final_size);
        wr.wr.send_flags |= xlt_wr_final_send_flags(flags);
        wr.xlt_size = sg.length;

        dma_sync_single_for_device(ddev, sg.addr, sg.length, DMA_TO_DEVICE);
        err = mlx5_ib_post_send_wait(dev, &wr);

err:
        sg.length = orig_sg_length;
        mlx5_ib_unmap_free_xlt(dev, mtt, &sg);
        return err;
}

/*
 * If ibmr is NULL it will be allocated by reg_create.
 * Else, the given ibmr will be used.
 */
static struct mlx5_ib_mr *reg_create(struct ib_pd *pd, struct ib_umem *umem,
                                     u64 iova, int access_flags,
                                     unsigned int page_size, bool populate)
{
        struct mlx5_ib_dev *dev = to_mdev(pd->device);
        struct mlx5_ib_mr *mr;
        __be64 *pas;
        void *mkc;
        int inlen;
        u32 *in;
        int err;
        bool pg_cap = !!(MLX5_CAP_GEN(dev->mdev, pg));

        if (!page_size)
                return ERR_PTR(-EINVAL);
        mr = kzalloc(sizeof(*mr), GFP_KERNEL);
        if (!mr)
                return ERR_PTR(-ENOMEM);

        mr->ibmr.pd = pd;
        mr->access_flags = access_flags;
        mr->page_shift = order_base_2(page_size);

        inlen = MLX5_ST_SZ_BYTES(create_mkey_in);
        if (populate)
                inlen += sizeof(*pas) *
                         roundup(ib_umem_num_dma_blocks(umem, page_size), 2);
        in = kvzalloc(inlen, GFP_KERNEL);
        if (!in) {
                err = -ENOMEM;
                goto err_1;
        }
        pas = (__be64 *)MLX5_ADDR_OF(create_mkey_in, in, klm_pas_mtt);
        if (populate) {
                if (WARN_ON(access_flags & IB_ACCESS_ON_DEMAND)) {
                        err = -EINVAL;
                        goto err_2;
                }
                mlx5_ib_populate_pas(umem, 1UL << mr->page_shift, pas,
                                     pg_cap ? MLX5_IB_MTT_PRESENT : 0);
        }

        /* The pg_access bit allows setting the access flags
         * in the page list submitted with the command. */
        MLX5_SET(create_mkey_in, in, pg_access, !!(pg_cap));

        mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);
        set_mkc_access_pd_addr_fields(mkc, access_flags, iova,
                                      populate ? pd : dev->umrc.pd);
        MLX5_SET(mkc, mkc, free, !populate);
        MLX5_SET(mkc, mkc, access_mode_1_0, MLX5_MKC_ACCESS_MODE_MTT);
        MLX5_SET(mkc, mkc, umr_en, 1);

        MLX5_SET64(mkc, mkc, len, umem->length);
        MLX5_SET(mkc, mkc, bsf_octword_size, 0);
        MLX5_SET(mkc, mkc, translations_octword_size,
                 get_octo_len(iova, umem->length, mr->page_shift));
        MLX5_SET(mkc, mkc, log_page_size, mr->page_shift);
        if (populate) {
                MLX5_SET(create_mkey_in, in, translations_octword_actual_size,
                         get_octo_len(iova, umem->length, mr->page_shift));
        }

        err = mlx5_ib_create_mkey(dev, &mr->mmkey, in, inlen);
        if (err) {
                mlx5_ib_warn(dev, "create mkey failed\n");
                goto err_2;
        }
        mr->mmkey.type = MLX5_MKEY_MR;
        mr->umem = umem;
        set_mr_fields(dev, mr, umem->length, access_flags);
        kvfree(in);

        mlx5_ib_dbg(dev, "mkey = 0x%x\n", mr->mmkey.key);

        return mr;

err_2:
        kvfree(in);
err_1:
        kfree(mr);
        return ERR_PTR(err);
}

static struct ib_mr *mlx5_ib_get_dm_mr(struct ib_pd *pd, u64 start_addr,
                                       u64 length, int acc, int mode)
{
        struct mlx5_ib_dev *dev = to_mdev(pd->device);
        int inlen = MLX5_ST_SZ_BYTES(create_mkey_in);
        struct mlx5_ib_mr *mr;
        void *mkc;
        u32 *in;
        int err;

        mr = kzalloc(sizeof(*mr), GFP_KERNEL);
        if (!mr)
                return ERR_PTR(-ENOMEM);

        in = kzalloc(inlen, GFP_KERNEL);
        if (!in) {
                err = -ENOMEM;
                goto err_free;
        }

        mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);

        MLX5_SET(mkc, mkc, access_mode_1_0, mode & 0x3);
        MLX5_SET(mkc, mkc, access_mode_4_2, (mode >> 2) & 0x7);
        MLX5_SET64(mkc, mkc, len, length);
        set_mkc_access_pd_addr_fields(mkc, acc, start_addr, pd);

        err = mlx5_ib_create_mkey(dev, &mr->mmkey, in, inlen);
        if (err)
                goto err_in;

        kfree(in);

        set_mr_fields(dev, mr, length, acc);

        return &mr->ibmr;

err_in:
        kfree(in);

err_free:
        kfree(mr);

        return ERR_PTR(err);
}

int mlx5_ib_advise_mr(struct ib_pd *pd,
                      enum ib_uverbs_advise_mr_advice advice,
                      u32 flags,
                      struct ib_sge *sg_list,
                      u32 num_sge,
                      struct uverbs_attr_bundle *attrs)
{
        if (advice != IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH &&
            advice != IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH_WRITE &&
            advice != IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH_NO_FAULT)
                return -EOPNOTSUPP;

        return mlx5_ib_advise_mr_prefetch(pd, advice, flags,
                                         sg_list, num_sge);
}

struct ib_mr *mlx5_ib_reg_dm_mr(struct ib_pd *pd, struct ib_dm *dm,
                                struct ib_dm_mr_attr *attr,
                                struct uverbs_attr_bundle *attrs)
{
        struct mlx5_ib_dm *mdm = to_mdm(dm);
        struct mlx5_core_dev *dev = to_mdev(dm->device)->mdev;
        u64 start_addr = mdm->dev_addr + attr->offset;
        int mode;

        switch (mdm->type) {
        case MLX5_IB_UAPI_DM_TYPE_MEMIC:
                if (attr->access_flags & ~MLX5_IB_DM_MEMIC_ALLOWED_ACCESS)
                        return ERR_PTR(-EINVAL);

                mode = MLX5_MKC_ACCESS_MODE_MEMIC;
                start_addr -= pci_resource_start(dev->pdev, 0);
                break;
        case MLX5_IB_UAPI_DM_TYPE_STEERING_SW_ICM:
        case MLX5_IB_UAPI_DM_TYPE_HEADER_MODIFY_SW_ICM:
                if (attr->access_flags & ~MLX5_IB_DM_SW_ICM_ALLOWED_ACCESS)
                        return ERR_PTR(-EINVAL);

                mode = MLX5_MKC_ACCESS_MODE_SW_ICM;
                break;
        default:
                return ERR_PTR(-EINVAL);
        }

        return mlx5_ib_get_dm_mr(pd, start_addr, attr->length,
                                 attr->access_flags, mode);
}

static struct ib_mr *create_real_mr(struct ib_pd *pd, struct ib_umem *umem,
                                    u64 iova, int access_flags)
{
        struct mlx5_ib_dev *dev = to_mdev(pd->device);
        struct mlx5_ib_mr *mr = NULL;
        bool xlt_with_umr;
        int err;

        xlt_with_umr = mlx5_ib_can_load_pas_with_umr(dev, umem->length);
        if (xlt_with_umr) {
                mr = alloc_cacheable_mr(pd, umem, iova, access_flags);
        } else {
                unsigned int page_size = mlx5_umem_find_best_pgsz(
                        umem, mkc, log_page_size, 0, iova);

                mutex_lock(&dev->slow_path_mutex);
                mr = reg_create(pd, umem, iova, access_flags, page_size, true);
                mutex_unlock(&dev->slow_path_mutex);
        }
        if (IS_ERR(mr)) {
                ib_umem_release(umem);
                return ERR_CAST(mr);
        }

        mlx5_ib_dbg(dev, "mkey 0x%x\n", mr->mmkey.key);

        atomic_add(ib_umem_num_pages(umem), &dev->mdev->priv.reg_pages);

        if (xlt_with_umr) {
                /*
                 * If the MR was created with reg_create then it will be
                 * configured properly but left disabled. It is safe to go ahead
                 * and configure it again via UMR while enabling it.
                 */
                err = mlx5_ib_update_mr_pas(mr, MLX5_IB_UPD_XLT_ENABLE);
                if (err) {
                        mlx5_ib_dereg_mr(&mr->ibmr, NULL);
                        return ERR_PTR(err);
                }
        }
        return &mr->ibmr;
}

static struct ib_mr *create_user_odp_mr(struct ib_pd *pd, u64 start, u64 length,
                                        u64 iova, int access_flags,
                                        struct ib_udata *udata)
{
        struct mlx5_ib_dev *dev = to_mdev(pd->device);
        struct ib_umem_odp *odp;
        struct mlx5_ib_mr *mr;
        int err;

        if (!IS_ENABLED(CONFIG_INFINIBAND_ON_DEMAND_PAGING))
                return ERR_PTR(-EOPNOTSUPP);

        err = mlx5r_odp_create_eq(dev, &dev->odp_pf_eq);
        if (err)
                return ERR_PTR(err);
        if (!start && length == U64_MAX) {
                if (iova != 0)
                        return ERR_PTR(-EINVAL);
                if (!(dev->odp_caps.general_caps & IB_ODP_SUPPORT_IMPLICIT))
                        return ERR_PTR(-EINVAL);

                mr = mlx5_ib_alloc_implicit_mr(to_mpd(pd), access_flags);
                if (IS_ERR(mr))
                        return ERR_CAST(mr);
                return &mr->ibmr;
        }

        /* ODP requires xlt update via umr to work. */
        if (!mlx5_ib_can_load_pas_with_umr(dev, length))
                return ERR_PTR(-EINVAL);

        odp = ib_umem_odp_get(&dev->ib_dev, start, length, access_flags,
                              &mlx5_mn_ops);
        if (IS_ERR(odp))
                return ERR_CAST(odp);

        mr = alloc_cacheable_mr(pd, &odp->umem, iova, access_flags);
        if (IS_ERR(mr)) {
                ib_umem_release(&odp->umem);
                return ERR_CAST(mr);
        }
        xa_init(&mr->implicit_children);

        odp->private = mr;
        err = mlx5r_store_odp_mkey(dev, &mr->mmkey);
        if (err)
                goto err_dereg_mr;

        err = mlx5_ib_init_odp_mr(mr);
        if (err)
                goto err_dereg_mr;
        return &mr->ibmr;

err_dereg_mr:
        mlx5_ib_dereg_mr(&mr->ibmr, NULL);
        return ERR_PTR(err);
}

struct ib_mr *mlx5_ib_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
                                  u64 iova, int access_flags,
                                  struct ib_udata *udata)
{
        struct mlx5_ib_dev *dev = to_mdev(pd->device);
        struct ib_umem *umem;

        if (!IS_ENABLED(CONFIG_INFINIBAND_USER_MEM))
                return ERR_PTR(-EOPNOTSUPP);

        mlx5_ib_dbg(dev, "start 0x%llx, iova 0x%llx, length 0x%llx, access_flags 0x%x\n",
                    start, iova, length, access_flags);

        if (access_flags & IB_ACCESS_ON_DEMAND)
                return create_user_odp_mr(pd, start, length, iova, access_flags,
                                          udata);
        umem = ib_umem_get(&dev->ib_dev, start, length, access_flags);
        if (IS_ERR(umem))
                return ERR_CAST(umem);
        return create_real_mr(pd, umem, iova, access_flags);
}

static void mlx5_ib_dmabuf_invalidate_cb(struct dma_buf_attachment *attach)
{
        struct ib_umem_dmabuf *umem_dmabuf = attach->importer_priv;
        struct mlx5_ib_mr *mr = umem_dmabuf->private;

        dma_resv_assert_held(umem_dmabuf->attach->dmabuf->resv);

        if (!umem_dmabuf->sgt)
                return;

        mlx5_ib_update_mr_pas(mr, MLX5_IB_UPD_XLT_ZAP);
        ib_umem_dmabuf_unmap_pages(umem_dmabuf);
}

static struct dma_buf_attach_ops mlx5_ib_dmabuf_attach_ops = {
        .allow_peer2peer = 1,
        .move_notify = mlx5_ib_dmabuf_invalidate_cb,
};

struct ib_mr *mlx5_ib_reg_user_mr_dmabuf(struct ib_pd *pd, u64 offset,
                                         u64 length, u64 virt_addr,
                                         int fd, 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_dmabuf *umem_dmabuf;
        int err;

        if (!IS_ENABLED(CONFIG_INFINIBAND_USER_MEM) ||
            !IS_ENABLED(CONFIG_INFINIBAND_ON_DEMAND_PAGING))
                return ERR_PTR(-EOPNOTSUPP);

        mlx5_ib_dbg(dev,
                    "offset 0x%llx, virt_addr 0x%llx, length 0x%llx, fd %d, access_flags 0x%x\n",
                    offset, virt_addr, length, fd, access_flags);

        /* dmabuf requires xlt update via umr to work. */
        if (!mlx5_ib_can_load_pas_with_umr(dev, length))
                return ERR_PTR(-EINVAL);

        umem_dmabuf = ib_umem_dmabuf_get(&dev->ib_dev, offset, length, fd,
                                         access_flags,
                                         &mlx5_ib_dmabuf_attach_ops);
        if (IS_ERR(umem_dmabuf)) {
                mlx5_ib_dbg(dev, "umem_dmabuf get failed (%ld)\n",
                            PTR_ERR(umem_dmabuf));
                return ERR_CAST(umem_dmabuf);
        }

        mr = alloc_cacheable_mr(pd, &umem_dmabuf->umem, virt_addr,
                                access_flags);
        if (IS_ERR(mr)) {
                ib_umem_release(&umem_dmabuf->umem);
                return ERR_CAST(mr);
        }

        mlx5_ib_dbg(dev, "mkey 0x%x\n", mr->mmkey.key);

        atomic_add(ib_umem_num_pages(mr->umem), &dev->mdev->priv.reg_pages);
        umem_dmabuf->private = mr;
        err = mlx5r_store_odp_mkey(dev, &mr->mmkey);
        if (err)
                goto err_dereg_mr;

        err = mlx5_ib_init_dmabuf_mr(mr);
        if (err)
                goto err_dereg_mr;
        return &mr->ibmr;

err_dereg_mr:
        mlx5_ib_dereg_mr(&mr->ibmr, NULL);
        return ERR_PTR(err);
}

/**
 * revoke_mr - Fence all DMA on the MR
 * @mr: The MR to fence
 *
 * Upon return the NIC will not be doing any DMA to the pages under the MR,
 * and any DMA in progress will be completed. Failure of this function
 * indicates the HW has failed catastrophically.
 */
static int revoke_mr(struct mlx5_ib_mr *mr)
{
        struct mlx5_umr_wr umrwr = {};

        if (mr_to_mdev(mr)->mdev->state == MLX5_DEVICE_STATE_INTERNAL_ERROR)
                return 0;

        umrwr.wr.send_flags = MLX5_IB_SEND_UMR_DISABLE_MR |
                              MLX5_IB_SEND_UMR_UPDATE_PD_ACCESS;
        umrwr.wr.opcode = MLX5_IB_WR_UMR;
        umrwr.pd = mr_to_mdev(mr)->umrc.pd;
        umrwr.mkey = mr->mmkey.key;
        umrwr.ignore_free_state = 1;

        return mlx5_ib_post_send_wait(mr_to_mdev(mr), &umrwr);
}

/*
 * True if the change in access flags can be done via UMR, only some access
 * flags can be updated.
 */
static bool can_use_umr_rereg_access(struct mlx5_ib_dev *dev,
                                     unsigned int current_access_flags,
                                     unsigned int target_access_flags)
{
        unsigned int diffs = current_access_flags ^ target_access_flags;

        if (diffs & ~(IB_ACCESS_LOCAL_WRITE | IB_ACCESS_REMOTE_WRITE |
                      IB_ACCESS_REMOTE_READ | IB_ACCESS_RELAXED_ORDERING))
                return false;
        return mlx5_ib_can_reconfig_with_umr(dev, current_access_flags,
                                             target_access_flags);
}

static int umr_rereg_pd_access(struct mlx5_ib_mr *mr, struct ib_pd *pd,
                               int access_flags)
{
        struct mlx5_ib_dev *dev = to_mdev(mr->ibmr.device);
        struct mlx5_umr_wr umrwr = {
                .wr = {
                        .send_flags = MLX5_IB_SEND_UMR_FAIL_IF_FREE |
                                      MLX5_IB_SEND_UMR_UPDATE_PD_ACCESS,
                        .opcode = MLX5_IB_WR_UMR,
                },
                .mkey = mr->mmkey.key,
                .pd = pd,
                .access_flags = access_flags,
        };
        int err;

        err = mlx5_ib_post_send_wait(dev, &umrwr);
        if (err)
                return err;

        mr->access_flags = access_flags;
        mr->mmkey.pd = to_mpd(pd)->pdn;
        return 0;
}

static bool can_use_umr_rereg_pas(struct mlx5_ib_mr *mr,
                                  struct ib_umem *new_umem,
                                  int new_access_flags, u64 iova,
                                  unsigned long *page_size)
{
        struct mlx5_ib_dev *dev = to_mdev(mr->ibmr.device);

        /* We only track the allocated sizes of MRs from the cache */
        if (!mr->cache_ent)
                return false;
        if (!mlx5_ib_can_load_pas_with_umr(dev, new_umem->length))
                return false;

        *page_size =
                mlx5_umem_find_best_pgsz(new_umem, mkc, log_page_size, 0, iova);
        if (WARN_ON(!*page_size))
                return false;
        return (1ULL << mr->cache_ent->order) >=
               ib_umem_num_dma_blocks(new_umem, *page_size);
}

static int umr_rereg_pas(struct mlx5_ib_mr *mr, struct ib_pd *pd,
                         int access_flags, int flags, struct ib_umem *new_umem,
                         u64 iova, unsigned long page_size)
{
        struct mlx5_ib_dev *dev = to_mdev(mr->ibmr.device);
        int upd_flags = MLX5_IB_UPD_XLT_ADDR | MLX5_IB_UPD_XLT_ENABLE;
        struct ib_umem *old_umem = mr->umem;
        int err;

        /*
         * To keep everything simple the MR is revoked before we start to mess
         * with it. This ensure the change is atomic relative to any use of the
         * MR.
         */
        err = revoke_mr(mr);
        if (err)
                return err;

        if (flags & IB_MR_REREG_PD) {
                mr->ibmr.pd = pd;
                mr->mmkey.pd = to_mpd(pd)->pdn;
                upd_flags |= MLX5_IB_UPD_XLT_PD;
        }
        if (flags & IB_MR_REREG_ACCESS) {
                mr->access_flags = access_flags;
                upd_flags |= MLX5_IB_UPD_XLT_ACCESS;
        }

        mr->ibmr.length = new_umem->length;
        mr->mmkey.iova = iova;
        mr->mmkey.size = new_umem->length;
        mr->page_shift = order_base_2(page_size);
        mr->umem = new_umem;
        err = mlx5_ib_update_mr_pas(mr, upd_flags);
        if (err) {
                /*
                 * The MR is revoked at this point so there is no issue to free
                 * new_umem.
                 */
                mr->umem = old_umem;
                return err;
        }

        atomic_sub(ib_umem_num_pages(old_umem), &dev->mdev->priv.reg_pages);
        ib_umem_release(old_umem);
        atomic_add(ib_umem_num_pages(new_umem), &dev->mdev->priv.reg_pages);
        return 0;
}

struct ib_mr *mlx5_ib_rereg_user_mr(struct ib_mr *ib_mr, int flags, u64 start,
                                    u64 length, u64 iova, int new_access_flags,
                                    struct ib_pd *new_pd,
                                    struct ib_udata *udata)
{
        struct mlx5_ib_dev *dev = to_mdev(ib_mr->device);
        struct mlx5_ib_mr *mr = to_mmr(ib_mr);
        int err;

        if (!IS_ENABLED(CONFIG_INFINIBAND_USER_MEM))
                return ERR_PTR(-EOPNOTSUPP);

        mlx5_ib_dbg(
                dev,
                "start 0x%llx, iova 0x%llx, length 0x%llx, access_flags 0x%x\n",
                start, iova, length, new_access_flags);

        if (flags & ~(IB_MR_REREG_TRANS | IB_MR_REREG_PD | IB_MR_REREG_ACCESS))
                return ERR_PTR(-EOPNOTSUPP);

        if (!(flags & IB_MR_REREG_ACCESS))
                new_access_flags = mr->access_flags;
        if (!(flags & IB_MR_REREG_PD))
                new_pd = ib_mr->pd;

        if (!(flags & IB_MR_REREG_TRANS)) {
                struct ib_umem *umem;

                /* Fast path for PD/access change */
                if (can_use_umr_rereg_access(dev, mr->access_flags,
                                             new_access_flags)) {
                        err = umr_rereg_pd_access(mr, new_pd, new_access_flags);
                        if (err)
                                return ERR_PTR(err);
                        return NULL;
                }
                /* DM or ODP MR's don't have a normal umem so we can't re-use it */
                if (!mr->umem || is_odp_mr(mr) || is_dmabuf_mr(mr))
                        goto recreate;

                /*
                 * Only one active MR can refer to a umem at one time, revoke
                 * the old MR before assigning the umem to the new one.
                 */
                err = revoke_mr(mr);
                if (err)
                        return ERR_PTR(err);
                umem = mr->umem;
                mr->umem = NULL;
                atomic_sub(ib_umem_num_pages(umem), &dev->mdev->priv.reg_pages);

                return create_real_mr(new_pd, umem, mr->mmkey.iova,
                                      new_access_flags);
        }

        /*
         * DM doesn't have a PAS list so we can't re-use it, odp/dmabuf does
         * but the logic around releasing the umem is different
         */
        if (!mr->umem || is_odp_mr(mr) || is_dmabuf_mr(mr))
                goto recreate;

        if (!(new_access_flags & IB_ACCESS_ON_DEMAND) &&
            can_use_umr_rereg_access(dev, mr->access_flags, new_access_flags)) {
                struct ib_umem *new_umem;
                unsigned long page_size;

                new_umem = ib_umem_get(&dev->ib_dev, start, length,
                                       new_access_flags);
                if (IS_ERR(new_umem))
                        return ERR_CAST(new_umem);

                /* Fast path for PAS change */
                if (can_use_umr_rereg_pas(mr, new_umem, new_access_flags, iova,
                                          &page_size)) {
                        err = umr_rereg_pas(mr, new_pd, new_access_flags, flags,
                                            new_umem, iova, page_size);
                        if (err) {
                                ib_umem_release(new_umem);
                                return ERR_PTR(err);
                        }
                        return NULL;
                }
                return create_real_mr(new_pd, new_umem, iova, new_access_flags);
        }

        /*
         * Everything else has no state we can preserve, just create a new MR
         * from scratch
         */
recreate:
        return mlx5_ib_reg_user_mr(new_pd, start, length, iova,
                                   new_access_flags, udata);
}

static int
mlx5_alloc_priv_descs(struct ib_device *device,
                      struct mlx5_ib_mr *mr,
                      int ndescs,
                      int desc_size)
{
        struct mlx5_ib_dev *dev = to_mdev(device);
        struct device *ddev = &dev->mdev->pdev->dev;
        int size = ndescs * desc_size;
        int add_size;
        int ret;

        add_size = max_t(int, MLX5_UMR_ALIGN - ARCH_KMALLOC_MINALIGN, 0);

        mr->descs_alloc = kzalloc(size + add_size, GFP_KERNEL);
        if (!mr->descs_alloc)
                return -ENOMEM;

        mr->descs = PTR_ALIGN(mr->descs_alloc, MLX5_UMR_ALIGN);

        mr->desc_map = dma_map_single(ddev, mr->descs, size, DMA_TO_DEVICE);
        if (dma_mapping_error(ddev, mr->desc_map)) {
                ret = -ENOMEM;
                goto err;
        }

        return 0;
err:
        kfree(mr->descs_alloc);

        return ret;
}

static void
mlx5_free_priv_descs(struct mlx5_ib_mr *mr)
{
        if (!mr->umem && mr->descs) {
                struct ib_device *device = mr->ibmr.device;
                int size = mr->max_descs * mr->desc_size;
                struct mlx5_ib_dev *dev = to_mdev(device);

                dma_unmap_single(&dev->mdev->pdev->dev, mr->desc_map, size,
                                 DMA_TO_DEVICE);
                kfree(mr->descs_alloc);
                mr->descs = NULL;
        }
}

int mlx5_ib_dereg_mr(struct ib_mr *ibmr, struct ib_udata *udata)
{
        struct mlx5_ib_mr *mr = to_mmr(ibmr);
        struct mlx5_ib_dev *dev = to_mdev(ibmr->device);
        int rc;

        /*
         * Any async use of the mr must hold the refcount, once the refcount
         * goes to zero no other thread, such as ODP page faults, prefetch, any
         * UMR activity, etc can touch the mkey. Thus it is safe to destroy it.
         */
        if (IS_ENABLED(CONFIG_INFINIBAND_ON_DEMAND_PAGING) &&
            refcount_read(&mr->mmkey.usecount) != 0 &&
            xa_erase(&mr_to_mdev(mr)->odp_mkeys, mlx5_base_mkey(mr->mmkey.key)))
                mlx5r_deref_wait_odp_mkey(&mr->mmkey);

        if (ibmr->type == IB_MR_TYPE_INTEGRITY) {
                xa_cmpxchg(&dev->sig_mrs, mlx5_base_mkey(mr->mmkey.key),
                           mr->sig, NULL, GFP_KERNEL);

                if (mr->mtt_mr) {
                        rc = mlx5_ib_dereg_mr(&mr->mtt_mr->ibmr, NULL);
                        if (rc)
                                return rc;
                        mr->mtt_mr = NULL;
                }
                if (mr->klm_mr) {
                        rc = mlx5_ib_dereg_mr(&mr->klm_mr->ibmr, NULL);
                        if (rc)
                                return rc;
                        mr->klm_mr = NULL;
                }

                if (mlx5_core_destroy_psv(dev->mdev,
                                          mr->sig->psv_memory.psv_idx))
                        mlx5_ib_warn(dev, "failed to destroy mem psv %d\n",
                                     mr->sig->psv_memory.psv_idx);
                if (mlx5_core_destroy_psv(dev->mdev, mr->sig->psv_wire.psv_idx))
                        mlx5_ib_warn(dev, "failed to destroy wire psv %d\n",
                                     mr->sig->psv_wire.psv_idx);
                kfree(mr->sig);
                mr->sig = NULL;
        }

        /* Stop DMA */
        if (mr->cache_ent) {
                if (revoke_mr(mr)) {
                        spin_lock_irq(&mr->cache_ent->lock);
                        mr->cache_ent->total_mrs--;
                        spin_unlock_irq(&mr->cache_ent->lock);
                        mr->cache_ent = NULL;
                }
        }
        if (!mr->cache_ent) {
                rc = destroy_mkey(to_mdev(mr->ibmr.device), mr);
                if (rc)
                        return rc;
        }

        if (mr->umem) {
                bool is_odp = is_odp_mr(mr);

                if (!is_odp)
                        atomic_sub(ib_umem_num_pages(mr->umem),
                                   &dev->mdev->priv.reg_pages);
                ib_umem_release(mr->umem);
                if (is_odp)
                        mlx5_ib_free_odp_mr(mr);
        }

        if (mr->cache_ent) {
                mlx5_mr_cache_free(dev, mr);

        } else {
                mlx5_free_priv_descs(mr);
                kfree(mr);
        }
        return 0;
}

static void mlx5_set_umr_free_mkey(struct ib_pd *pd, u32 *in, int ndescs,
                                   int access_mode, int page_shift)
{
        void *mkc;

        mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);

        /* This is only used from the kernel, so setting the PD is OK. */
        set_mkc_access_pd_addr_fields(mkc, IB_ACCESS_RELAXED_ORDERING, 0, pd);
        MLX5_SET(mkc, mkc, free, 1);
        MLX5_SET(mkc, mkc, translations_octword_size, ndescs);
        MLX5_SET(mkc, mkc, access_mode_1_0, access_mode & 0x3);
        MLX5_SET(mkc, mkc, access_mode_4_2, (access_mode >> 2) & 0x7);
        MLX5_SET(mkc, mkc, umr_en, 1);
        MLX5_SET(mkc, mkc, log_page_size, page_shift);
}

static int _mlx5_alloc_mkey_descs(struct ib_pd *pd, struct mlx5_ib_mr *mr,
                                  int ndescs, int desc_size, int page_shift,
                                  int access_mode, u32 *in, int inlen)
{
        struct mlx5_ib_dev *dev = to_mdev(pd->device);
        int err;

        mr->access_mode = access_mode;
        mr->desc_size = desc_size;
        mr->max_descs = ndescs;

        err = mlx5_alloc_priv_descs(pd->device, mr, ndescs, desc_size);
        if (err)
                return err;

        mlx5_set_umr_free_mkey(pd, in, ndescs, access_mode, page_shift);

        err = mlx5_ib_create_mkey(dev, &mr->mmkey, in, inlen);
        if (err)
                goto err_free_descs;

        mr->mmkey.type = MLX5_MKEY_MR;
        mr->ibmr.lkey = mr->mmkey.key;
        mr->ibmr.rkey = mr->mmkey.key;

        return 0;

err_free_descs:
        mlx5_free_priv_descs(mr);
        return err;
}

static struct mlx5_ib_mr *mlx5_ib_alloc_pi_mr(struct ib_pd *pd,
                                u32 max_num_sg, u32 max_num_meta_sg,
                                int desc_size, int access_mode)
{
        int inlen = MLX5_ST_SZ_BYTES(create_mkey_in);
        int ndescs = ALIGN(max_num_sg + max_num_meta_sg, 4);
        int page_shift = 0;
        struct mlx5_ib_mr *mr;
        u32 *in;
        int err;

        mr = kzalloc(sizeof(*mr), GFP_KERNEL);
        if (!mr)
                return ERR_PTR(-ENOMEM);

        mr->ibmr.pd = pd;
        mr->ibmr.device = pd->device;

        in = kzalloc(inlen, GFP_KERNEL);
        if (!in) {
                err = -ENOMEM;
                goto err_free;
        }

        if (access_mode == MLX5_MKC_ACCESS_MODE_MTT)
                page_shift = PAGE_SHIFT;

        err = _mlx5_alloc_mkey_descs(pd, mr, ndescs, desc_size, page_shift,
                                     access_mode, in, inlen);
        if (err)
                goto err_free_in;

        mr->umem = NULL;
        kfree(in);

        return mr;

err_free_in:
        kfree(in);
err_free:
        kfree(mr);
        return ERR_PTR(err);
}

static int mlx5_alloc_mem_reg_descs(struct ib_pd *pd, struct mlx5_ib_mr *mr,
                                    int ndescs, u32 *in, int inlen)
{
        return _mlx5_alloc_mkey_descs(pd, mr, ndescs, sizeof(struct mlx5_mtt),
                                      PAGE_SHIFT, MLX5_MKC_ACCESS_MODE_MTT, in,
                                      inlen);
}

static int mlx5_alloc_sg_gaps_descs(struct ib_pd *pd, struct mlx5_ib_mr *mr,
                                    int ndescs, u32 *in, int inlen)
{
        return _mlx5_alloc_mkey_descs(pd, mr, ndescs, sizeof(struct mlx5_klm),
                                      0, MLX5_MKC_ACCESS_MODE_KLMS, in, inlen);
}

static int mlx5_alloc_integrity_descs(struct ib_pd *pd, struct mlx5_ib_mr *mr,
                                      int max_num_sg, int max_num_meta_sg,
                                      u32 *in, int inlen)
{
        struct mlx5_ib_dev *dev = to_mdev(pd->device);
        u32 psv_index[2];
        void *mkc;
        int err;

        mr->sig = kzalloc(sizeof(*mr->sig), GFP_KERNEL);
        if (!mr->sig)
                return -ENOMEM;

        /* create mem & wire PSVs */
        err = mlx5_core_create_psv(dev->mdev, to_mpd(pd)->pdn, 2, psv_index);
        if (err)
                goto err_free_sig;

        mr->sig->psv_memory.psv_idx = psv_index[0];
        mr->sig->psv_wire.psv_idx = psv_index[1];

        mr->sig->sig_status_checked = true;
        mr->sig->sig_err_exists = false;
        /* Next UMR, Arm SIGERR */
        ++mr->sig->sigerr_count;
        mr->klm_mr = mlx5_ib_alloc_pi_mr(pd, max_num_sg, max_num_meta_sg,
                                         sizeof(struct mlx5_klm),
                                         MLX5_MKC_ACCESS_MODE_KLMS);
        if (IS_ERR(mr->klm_mr)) {
                err = PTR_ERR(mr->klm_mr);
                goto err_destroy_psv;
        }
        mr->mtt_mr = mlx5_ib_alloc_pi_mr(pd, max_num_sg, max_num_meta_sg,
                                         sizeof(struct mlx5_mtt),
                                         MLX5_MKC_ACCESS_MODE_MTT);
        if (IS_ERR(mr->mtt_mr)) {
                err = PTR_ERR(mr->mtt_mr);
                goto err_free_klm_mr;
        }

        /* Set bsf descriptors for mkey */
        mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);
        MLX5_SET(mkc, mkc, bsf_en, 1);
        MLX5_SET(mkc, mkc, bsf_octword_size, MLX5_MKEY_BSF_OCTO_SIZE);

        err = _mlx5_alloc_mkey_descs(pd, mr, 4, sizeof(struct mlx5_klm), 0,
                                     MLX5_MKC_ACCESS_MODE_KLMS, in, inlen);
        if (err)
                goto err_free_mtt_mr;

        err = xa_err(xa_store(&dev->sig_mrs, mlx5_base_mkey(mr->mmkey.key),
                              mr->sig, GFP_KERNEL));
        if (err)
                goto err_free_descs;
        return 0;

err_free_descs:
        destroy_mkey(dev, mr);
        mlx5_free_priv_descs(mr);
err_free_mtt_mr:
        mlx5_ib_dereg_mr(&mr->mtt_mr->ibmr, NULL);
        mr->mtt_mr = NULL;
err_free_klm_mr:
        mlx5_ib_dereg_mr(&mr->klm_mr->ibmr, NULL);
        mr->klm_mr = NULL;
err_destroy_psv:
        if (mlx5_core_destroy_psv(dev->mdev, mr->sig->psv_memory.psv_idx))
                mlx5_ib_warn(dev, "failed to destroy mem psv %d\n",
                             mr->sig->psv_memory.psv_idx);
        if (mlx5_core_destroy_psv(dev->mdev, mr->sig->psv_wire.psv_idx))
                mlx5_ib_warn(dev, "failed to destroy wire psv %d\n",
                             mr->sig->psv_wire.psv_idx);
err_free_sig:
        kfree(mr->sig);

        return err;
}

static struct ib_mr *__mlx5_ib_alloc_mr(struct ib_pd *pd,
                                        enum ib_mr_type mr_type, u32 max_num_sg,
                                        u32 max_num_meta_sg)
{
        struct mlx5_ib_dev *dev = to_mdev(pd->device);
        int inlen = MLX5_ST_SZ_BYTES(create_mkey_in);
        int ndescs = ALIGN(max_num_sg, 4);
        struct mlx5_ib_mr *mr;
        u32 *in;
        int err;

        mr = kzalloc(sizeof(*mr), GFP_KERNEL);
        if (!mr)
                return ERR_PTR(-ENOMEM);

        in = kzalloc(inlen, GFP_KERNEL);
        if (!in) {
                err = -ENOMEM;
                goto err_free;
        }

        mr->ibmr.device = pd->device;
        mr->umem = NULL;

        switch (mr_type) {
        case IB_MR_TYPE_MEM_REG:
                err = mlx5_alloc_mem_reg_descs(pd, mr, ndescs, in, inlen);
                break;
        case IB_MR_TYPE_SG_GAPS:
                err = mlx5_alloc_sg_gaps_descs(pd, mr, ndescs, in, inlen);
                break;
        case IB_MR_TYPE_INTEGRITY:
                err = mlx5_alloc_integrity_descs(pd, mr, max_num_sg,
                                                 max_num_meta_sg, in, inlen);
                break;
        default:
                mlx5_ib_warn(dev, "Invalid mr type %d\n", mr_type);
                err = -EINVAL;
        }

        if (err)
                goto err_free_in;

        kfree(in);

        return &mr->ibmr;

err_free_in:
        kfree(in);
err_free:
        kfree(mr);
        return ERR_PTR(err);
}

struct ib_mr *mlx5_ib_alloc_mr(struct ib_pd *pd, enum ib_mr_type mr_type,
                               u32 max_num_sg)
{
        return __mlx5_ib_alloc_mr(pd, mr_type, max_num_sg, 0);
}

struct ib_mr *mlx5_ib_alloc_mr_integrity(struct ib_pd *pd,
                                         u32 max_num_sg, u32 max_num_meta_sg)
{
        return __mlx5_ib_alloc_mr(pd, IB_MR_TYPE_INTEGRITY, max_num_sg,
                                  max_num_meta_sg);
}

int mlx5_ib_alloc_mw(struct ib_mw *ibmw, struct ib_udata *udata)
{
        struct mlx5_ib_dev *dev = to_mdev(ibmw->device);
        int inlen = MLX5_ST_SZ_BYTES(create_mkey_in);
        struct mlx5_ib_mw *mw = to_mmw(ibmw);
        u32 *in = NULL;
        void *mkc;
        int ndescs;
        int err;
        struct mlx5_ib_alloc_mw req = {};
        struct {
                __u32   comp_mask;
                __u32   response_length;
        } resp = {};

        err = ib_copy_from_udata(&req, udata, min(udata->inlen, sizeof(req)));
        if (err)
                return err;

        if (req.comp_mask || req.reserved1 || req.reserved2)
                return -EOPNOTSUPP;

        if (udata->inlen > sizeof(req) &&
            !ib_is_udata_cleared(udata, sizeof(req),
                                 udata->inlen - sizeof(req)))
                return -EOPNOTSUPP;

        ndescs = req.num_klms ? roundup(req.num_klms, 4) : roundup(1, 4);

        in = kzalloc(inlen, GFP_KERNEL);
        if (!in) {
                err = -ENOMEM;
                goto free;
        }

        mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);

        MLX5_SET(mkc, mkc, free, 1);
        MLX5_SET(mkc, mkc, translations_octword_size, ndescs);
        MLX5_SET(mkc, mkc, pd, to_mpd(ibmw->pd)->pdn);
        MLX5_SET(mkc, mkc, umr_en, 1);
        MLX5_SET(mkc, mkc, lr, 1);
        MLX5_SET(mkc, mkc, access_mode_1_0, MLX5_MKC_ACCESS_MODE_KLMS);
        MLX5_SET(mkc, mkc, en_rinval, !!((ibmw->type == IB_MW_TYPE_2)));
        MLX5_SET(mkc, mkc, qpn, 0xffffff);

        err = mlx5_ib_create_mkey(dev, &mw->mmkey, in, inlen);
        if (err)
                goto free;

        mw->mmkey.type = MLX5_MKEY_MW;
        ibmw->rkey = mw->mmkey.key;
        mw->ndescs = ndescs;

        resp.response_length =
                min(offsetofend(typeof(resp), response_length), udata->outlen);
        if (resp.response_length) {
                err = ib_copy_to_udata(udata, &resp, resp.response_length);
                if (err)
                        goto free_mkey;
        }

        if (IS_ENABLED(CONFIG_INFINIBAND_ON_DEMAND_PAGING)) {
                err = mlx5r_store_odp_mkey(dev, &mw->mmkey);
                if (err)
                        goto free_mkey;
        }

        kfree(in);
        return 0;

free_mkey:
        mlx5_core_destroy_mkey(dev->mdev, &mw->mmkey);
free:
        kfree(in);
        return err;
}

int mlx5_ib_dealloc_mw(struct ib_mw *mw)
{
        struct mlx5_ib_dev *dev = to_mdev(mw->device);
        struct mlx5_ib_mw *mmw = to_mmw(mw);

        if (IS_ENABLED(CONFIG_INFINIBAND_ON_DEMAND_PAGING) &&
            xa_erase(&dev->odp_mkeys, mlx5_base_mkey(mmw->mmkey.key)))
                /*
                 * pagefault_single_data_segment() may be accessing mmw
                 * if the user bound an ODP MR to this MW.
                 */
                mlx5r_deref_wait_odp_mkey(&mmw->mmkey);

        return mlx5_core_destroy_mkey(dev->mdev, &mmw->mmkey);
}

int mlx5_ib_check_mr_status(struct ib_mr *ibmr, u32 check_mask,
                            struct ib_mr_status *mr_status)
{
        struct mlx5_ib_mr *mmr = to_mmr(ibmr);
        int ret = 0;

        if (check_mask & ~IB_MR_CHECK_SIG_STATUS) {
                pr_err("Invalid status check mask\n");
                ret = -EINVAL;
                goto done;
        }

        mr_status->fail_status = 0;
        if (check_mask & IB_MR_CHECK_SIG_STATUS) {
                if (!mmr->sig) {
                        ret = -EINVAL;
                        pr_err("signature status check requested on a non-signature enabled MR\n");
                        goto done;
                }

                mmr->sig->sig_status_checked = true;
                if (!mmr->sig->sig_err_exists)
                        goto done;

                if (ibmr->lkey == mmr->sig->err_item.key)
                        memcpy(&mr_status->sig_err, &mmr->sig->err_item,
                               sizeof(mr_status->sig_err));
                else {
                        mr_status->sig_err.err_type = IB_SIG_BAD_GUARD;
                        mr_status->sig_err.sig_err_offset = 0;
                        mr_status->sig_err.key = mmr->sig->err_item.key;
                }

                mmr->sig->sig_err_exists = false;
                mr_status->fail_status |= IB_MR_CHECK_SIG_STATUS;
        }

done:
        return ret;
}

static int
mlx5_ib_map_pa_mr_sg_pi(struct ib_mr *ibmr, struct scatterlist *data_sg,
                        int data_sg_nents, unsigned int *data_sg_offset,
                        struct scatterlist *meta_sg, int meta_sg_nents,
                        unsigned int *meta_sg_offset)
{
        struct mlx5_ib_mr *mr = to_mmr(ibmr);
        unsigned int sg_offset = 0;
        int n = 0;

        mr->meta_length = 0;
        if (data_sg_nents == 1) {
                n++;
                mr->ndescs = 1;
                if (data_sg_offset)
                        sg_offset = *data_sg_offset;
                mr->data_length = sg_dma_len(data_sg) - sg_offset;
                mr->data_iova = sg_dma_address(data_sg) + sg_offset;
                if (meta_sg_nents == 1) {
                        n++;
                        mr->meta_ndescs = 1;
                        if (meta_sg_offset)
                                sg_offset = *meta_sg_offset;
                        else
                                sg_offset = 0;
                        mr->meta_length = sg_dma_len(meta_sg) - sg_offset;
                        mr->pi_iova = sg_dma_address(meta_sg) + sg_offset;
                }
                ibmr->length = mr->data_length + mr->meta_length;
        }

        return n;
}

static int
mlx5_ib_sg_to_klms(struct mlx5_ib_mr *mr,
                   struct scatterlist *sgl,
                   unsigned short sg_nents,
                   unsigned int *sg_offset_p,
                   struct scatterlist *meta_sgl,
                   unsigned short meta_sg_nents,
                   unsigned int *meta_sg_offset_p)
{
        struct scatterlist *sg = sgl;
        struct mlx5_klm *klms = mr->descs;
        unsigned int sg_offset = sg_offset_p ? *sg_offset_p : 0;
        u32 lkey = mr->ibmr.pd->local_dma_lkey;
        int i, j = 0;

        mr->ibmr.iova = sg_dma_address(sg) + sg_offset;
        mr->ibmr.length = 0;

        for_each_sg(sgl, sg, sg_nents, i) {
                if (unlikely(i >= mr->max_descs))
                        break;
                klms[i].va = cpu_to_be64(sg_dma_address(sg) + sg_offset);
                klms[i].bcount = cpu_to_be32(sg_dma_len(sg) - sg_offset);
                klms[i].key = cpu_to_be32(lkey);
                mr->ibmr.length += sg_dma_len(sg) - sg_offset;

                sg_offset = 0;
        }

        if (sg_offset_p)
                *sg_offset_p = sg_offset;

        mr->ndescs = i;
        mr->data_length = mr->ibmr.length;

        if (meta_sg_nents) {
                sg = meta_sgl;
                sg_offset = meta_sg_offset_p ? *meta_sg_offset_p : 0;
                for_each_sg(meta_sgl, sg, meta_sg_nents, j) {
                        if (unlikely(i + j >= mr->max_descs))
                                break;
                        klms[i + j].va = cpu_to_be64(sg_dma_address(sg) +
                                                     sg_offset);
                        klms[i + j].bcount = cpu_to_be32(sg_dma_len(sg) -
                                                         sg_offset);
                        klms[i + j].key = cpu_to_be32(lkey);
                        mr->ibmr.length += sg_dma_len(sg) - sg_offset;

                        sg_offset = 0;
                }
                if (meta_sg_offset_p)
                        *meta_sg_offset_p = sg_offset;

                mr->meta_ndescs = j;
                mr->meta_length = mr->ibmr.length - mr->data_length;
        }

        return i + j;
}

static int mlx5_set_page(struct ib_mr *ibmr, u64 addr)
{
        struct mlx5_ib_mr *mr = to_mmr(ibmr);
        __be64 *descs;

        if (unlikely(mr->ndescs == mr->max_descs))
                return -ENOMEM;

        descs = mr->descs;
        descs[mr->ndescs++] = cpu_to_be64(addr | MLX5_EN_RD | MLX5_EN_WR);

        return 0;
}

static int mlx5_set_page_pi(struct ib_mr *ibmr, u64 addr)
{
        struct mlx5_ib_mr *mr = to_mmr(ibmr);
        __be64 *descs;

        if (unlikely(mr->ndescs + mr->meta_ndescs == mr->max_descs))
                return -ENOMEM;

        descs = mr->descs;
        descs[mr->ndescs + mr->meta_ndescs++] =
                cpu_to_be64(addr | MLX5_EN_RD | MLX5_EN_WR);

        return 0;
}

static int
mlx5_ib_map_mtt_mr_sg_pi(struct ib_mr *ibmr, struct scatterlist *data_sg,
                         int data_sg_nents, unsigned int *data_sg_offset,
                         struct scatterlist *meta_sg, int meta_sg_nents,
                         unsigned int *meta_sg_offset)
{
        struct mlx5_ib_mr *mr = to_mmr(ibmr);
        struct mlx5_ib_mr *pi_mr = mr->mtt_mr;
        int n;

        pi_mr->ndescs = 0;
        pi_mr->meta_ndescs = 0;
        pi_mr->meta_length = 0;

        ib_dma_sync_single_for_cpu(ibmr->device, pi_mr->desc_map,
                                   pi_mr->desc_size * pi_mr->max_descs,
                                   DMA_TO_DEVICE);

        pi_mr->ibmr.page_size = ibmr->page_size;
        n = ib_sg_to_pages(&pi_mr->ibmr, data_sg, data_sg_nents, data_sg_offset,
                           mlx5_set_page);
        if (n != data_sg_nents)
                return n;

        pi_mr->data_iova = pi_mr->ibmr.iova;
        pi_mr->data_length = pi_mr->ibmr.length;
        pi_mr->ibmr.length = pi_mr->data_length;
        ibmr->length = pi_mr->data_length;

        if (meta_sg_nents) {
                u64 page_mask = ~((u64)ibmr->page_size - 1);
                u64 iova = pi_mr->data_iova;

                n += ib_sg_to_pages(&pi_mr->ibmr, meta_sg, meta_sg_nents,
                                    meta_sg_offset, mlx5_set_page_pi);

                pi_mr->meta_length = pi_mr->ibmr.length;
                /*
                 * PI address for the HW is the offset of the metadata address
                 * relative to the first data page address.
                 * It equals to first data page address + size of data pages +
                 * metadata offset at the first metadata page
                 */
                pi_mr->pi_iova = (iova & page_mask) +
                                 pi_mr->ndescs * ibmr->page_size +
                                 (pi_mr->ibmr.iova & ~page_mask);
                /*
                 * In order to use one MTT MR for data and metadata, we register
                 * also the gaps between the end of the data and the start of
                 * the metadata (the sig MR will verify that the HW will access
                 * to right addresses). This mapping is safe because we use
                 * internal mkey for the registration.
                 */
                pi_mr->ibmr.length = pi_mr->pi_iova + pi_mr->meta_length - iova;
                pi_mr->ibmr.iova = iova;
                ibmr->length += pi_mr->meta_length;
        }

        ib_dma_sync_single_for_device(ibmr->device, pi_mr->desc_map,
                                      pi_mr->desc_size * pi_mr->max_descs,
                                      DMA_TO_DEVICE);

        return n;
}

static int
mlx5_ib_map_klm_mr_sg_pi(struct ib_mr *ibmr, struct scatterlist *data_sg,
                         int data_sg_nents, unsigned int *data_sg_offset,
                         struct scatterlist *meta_sg, int meta_sg_nents,
                         unsigned int *meta_sg_offset)
{
        struct mlx5_ib_mr *mr = to_mmr(ibmr);
        struct mlx5_ib_mr *pi_mr = mr->klm_mr;
        int n;

        pi_mr->ndescs = 0;
        pi_mr->meta_ndescs = 0;
        pi_mr->meta_length = 0;

        ib_dma_sync_single_for_cpu(ibmr->device, pi_mr->desc_map,
                                   pi_mr->desc_size * pi_mr->max_descs,
                                   DMA_TO_DEVICE);

        n = mlx5_ib_sg_to_klms(pi_mr, data_sg, data_sg_nents, data_sg_offset,
                               meta_sg, meta_sg_nents, meta_sg_offset);

        ib_dma_sync_single_for_device(ibmr->device, pi_mr->desc_map,
                                      pi_mr->desc_size * pi_mr->max_descs,
                                      DMA_TO_DEVICE);

        /* This is zero-based memory region */
        pi_mr->data_iova = 0;
        pi_mr->ibmr.iova = 0;
        pi_mr->pi_iova = pi_mr->data_length;
        ibmr->length = pi_mr->ibmr.length;

        return n;
}

int mlx5_ib_map_mr_sg_pi(struct ib_mr *ibmr, struct scatterlist *data_sg,
                         int data_sg_nents, unsigned int *data_sg_offset,
                         struct scatterlist *meta_sg, int meta_sg_nents,
                         unsigned int *meta_sg_offset)
{
        struct mlx5_ib_mr *mr = to_mmr(ibmr);
        struct mlx5_ib_mr *pi_mr = NULL;
        int n;

        WARN_ON(ibmr->type != IB_MR_TYPE_INTEGRITY);

        mr->ndescs = 0;
        mr->data_length = 0;
        mr->data_iova = 0;
        mr->meta_ndescs = 0;
        mr->pi_iova = 0;
        /*
         * As a performance optimization, if possible, there is no need to
         * perform UMR operation to register the data/metadata buffers.
         * First try to map the sg lists to PA descriptors with local_dma_lkey.
         * Fallback to UMR only in case of a failure.
         */
        n = mlx5_ib_map_pa_mr_sg_pi(ibmr, data_sg, data_sg_nents,
                                    data_sg_offset, meta_sg, meta_sg_nents,
                                    meta_sg_offset);
        if (n == data_sg_nents + meta_sg_nents)
                goto out;
        /*
         * As a performance optimization, if possible, there is no need to map
         * the sg lists to KLM descriptors. First try to map the sg lists to MTT
         * descriptors and fallback to KLM only in case of a failure.
         * It's more efficient for the HW to work with MTT descriptors
         * (especially in high load).
         * Use KLM (indirect access) only if it's mandatory.
         */
        pi_mr = mr->mtt_mr;
        n = mlx5_ib_map_mtt_mr_sg_pi(ibmr, data_sg, data_sg_nents,
                                     data_sg_offset, meta_sg, meta_sg_nents,
                                     meta_sg_offset);
        if (n == data_sg_nents + meta_sg_nents)
                goto out;

        pi_mr = mr->klm_mr;
        n = mlx5_ib_map_klm_mr_sg_pi(ibmr, data_sg, data_sg_nents,
                                     data_sg_offset, meta_sg, meta_sg_nents,
                                     meta_sg_offset);
        if (unlikely(n != data_sg_nents + meta_sg_nents))
                return -ENOMEM;

out:
        /* This is zero-based memory region */
        ibmr->iova = 0;
        mr->pi_mr = pi_mr;
        if (pi_mr)
                ibmr->sig_attrs->meta_length = pi_mr->meta_length;
        else
                ibmr->sig_attrs->meta_length = mr->meta_length;

        return 0;
}

int mlx5_ib_map_mr_sg(struct ib_mr *ibmr, struct scatterlist *sg, int sg_nents,
                      unsigned int *sg_offset)
{
        struct mlx5_ib_mr *mr = to_mmr(ibmr);
        int n;

        mr->ndescs = 0;

        ib_dma_sync_single_for_cpu(ibmr->device, mr->desc_map,
                                   mr->desc_size * mr->max_descs,
                                   DMA_TO_DEVICE);

        if (mr->access_mode == MLX5_MKC_ACCESS_MODE_KLMS)
                n = mlx5_ib_sg_to_klms(mr, sg, sg_nents, sg_offset, NULL, 0,
                                       NULL);
        else
                n = ib_sg_to_pages(ibmr, sg, sg_nents, sg_offset,
                                mlx5_set_page);

        ib_dma_sync_single_for_device(ibmr->device, mr->desc_map,
                                      mr->desc_size * mr->max_descs,
                                      DMA_TO_DEVICE);

        return n;
}