RDMA/mlx5: Add TLP VAR region support and infrastructure

Add support for TLP (Transaction Layer Packet) VAR regions used by
software-defined device emulation. TLP VAR provides dedicated response
gateways for sending TLP responses back to the host in TLP emulation
scenarios.

Signed-off-by: Maher Sanalla <msanalla@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>

diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index 487e162cd45773e44dd95f06b2656c3f77e6b522..64708a97f26c2e1ee3acc6b03926f62b53804afe 100644 (file)
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -2516,6 +2516,15 @@ mlx5_ib_pgoff_to_mmap_entry(struct ib_ucontext *ucontext, off_t pg_off)
        return rdma_user_mmap_entry_get_pgoff(ucontext, entry_pgoff);
 }
 
+static void mlx5_ib_free_var_mmap_entry(struct mlx5_user_mmap_entry *mentry,
+                                       struct mlx5_var_region *var_region)
+{
+       mutex_lock(&var_region->bitmap_lock);
+       clear_bit(mentry->page_idx, var_region->bitmap);
+       mutex_unlock(&var_region->bitmap_lock);
+       kfree(mentry);
+}
+
 static void mlx5_ib_mmap_free(struct rdma_user_mmap_entry *entry)
 {
        struct mlx5_user_mmap_entry *mentry = to_mmmap(entry);
@@ -2531,10 +2540,11 @@ static void mlx5_ib_mmap_free(struct rdma_user_mmap_entry *entry)
                break;
        case MLX5_IB_MMAP_TYPE_VAR:
                var_region = &var_table->var_region;
-               mutex_lock(&var_region->bitmap_lock);
-               clear_bit(mentry->page_idx, var_region->bitmap);
-               mutex_unlock(&var_region->bitmap_lock);
-               kfree(mentry);
+               mlx5_ib_free_var_mmap_entry(mentry, var_region);
+               break;
+       case MLX5_IB_MMAP_TYPE_TLP_VAR:
+               var_region = &var_table->tlp_var_region;
+               mlx5_ib_free_var_mmap_entry(mentry, var_region);
                break;
        case MLX5_IB_MMAP_TYPE_UAR_WC:
        case MLX5_IB_MMAP_TYPE_UAR_NC:
@@ -2685,6 +2695,7 @@ static int mlx5_ib_mmap_offset(struct mlx5_ib_dev *dev,
        mentry = to_mmmap(entry);
        pfn = (mentry->address >> PAGE_SHIFT);
        if (mentry->mmap_flag == MLX5_IB_MMAP_TYPE_VAR ||
+           mentry->mmap_flag == MLX5_IB_MMAP_TYPE_TLP_VAR ||
            mentry->mmap_flag == MLX5_IB_MMAP_TYPE_UAR_NC)
                prot = pgprot_noncached(vma->vm_page_prot);
        else
@@ -4637,6 +4648,28 @@ static int mlx5_ib_init_var_region(struct mlx5_ib_dev *dev)
        return (var_region->bitmap) ? 0 : -ENOMEM;
 }
 
+static int mlx5_ib_init_tlp_var_region(struct mlx5_ib_dev *dev)
+{
+       struct mlx5_var_region *var_region = &dev->var_table.tlp_var_region;
+       struct mlx5_core_dev *mdev = dev->mdev;
+       u8 log_tlp_var_stride;
+
+       log_tlp_var_stride =
+               MLX5_CAP_DEV_TLP_EMULATION(mdev, log_tlp_rsp_gw_page_stride);
+       var_region->hw_start_addr =
+               dev->mdev->bar_addr +
+               MLX5_CAP64_DEV_TLP_EMULATION(mdev, tlp_rsp_gw_pages_bar_offset);
+
+       var_region->stride_size = (1ULL << log_tlp_var_stride) * 4096;
+       var_region->num_var_hw_entries =
+               MLX5_CAP_DEV_TLP_EMULATION(mdev, tlp_rsp_gw_num_pages);
+
+       mutex_init(&var_region->bitmap_lock);
+       var_region->bitmap = bitmap_zalloc(var_region->num_var_hw_entries,
+                                          GFP_KERNEL);
+       return (var_region->bitmap) ? 0 : -ENOMEM;
+}
+
 static void mlx5_ib_cleanup_ucaps(struct mlx5_ib_dev *dev)
 {
        if (MLX5_CAP_GEN(dev->mdev, uctx_cap) & MLX5_UCTX_CAP_RDMA_CTRL)
@@ -4672,13 +4705,19 @@ remove_local:
        return ret;
 }
 
+static void mlx5_ib_cleanup_var_table(struct mlx5_ib_dev *dev)
+{
+       bitmap_free(dev->var_table.var_region.bitmap);
+       bitmap_free(dev->var_table.tlp_var_region.bitmap);
+}
+
 static void mlx5_ib_stage_caps_cleanup(struct mlx5_ib_dev *dev)
 {
        if (MLX5_CAP_GEN_2_64(dev->mdev, general_obj_types_127_64) &
            MLX5_HCA_CAP_2_GENERAL_OBJECT_TYPES_RDMA_CTRL)
                mlx5_ib_cleanup_ucaps(dev);
 
-       bitmap_free(dev->var_table.var_region.bitmap);
+       mlx5_ib_cleanup_var_table(dev);
 }
 
 static int mlx5_ib_stage_caps_init(struct mlx5_ib_dev *dev)
@@ -4738,10 +4777,18 @@ static int mlx5_ib_stage_caps_init(struct mlx5_ib_dev *dev)
                        goto err_ucaps;
        }
 
+       if (MLX5_CAP_GEN(dev->mdev, tlp_device_emulation_manager)) {
+               err = mlx5_ib_init_tlp_var_region(dev);
+               if (err)
+                       goto err_tlp_var;
+       }
+
        dev->ib_dev.use_cq_dim = true;
 
        return 0;
 
+err_tlp_var:
+       mlx5_ib_cleanup_ucaps(dev);
 err_ucaps:
        bitmap_free(dev->var_table.var_region.bitmap);
        return err;

diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h
index 2c4a3bdd84fc3e544f010c48c9beef4432d1e4d7..1396bbe45826ab329ad4a167505aae78c5bddca8 100644 (file)
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -162,6 +162,7 @@ enum mlx5_ib_mmap_type {
        MLX5_IB_MMAP_TYPE_UAR_WC = 3,
        MLX5_IB_MMAP_TYPE_UAR_NC = 4,
        MLX5_IB_MMAP_TYPE_MEMIC_OP = 5,
+       MLX5_IB_MMAP_TYPE_TLP_VAR = 6,
 };
 
 struct mlx5_bfreg_info {
@@ -1068,6 +1069,7 @@ struct mlx5_var_region {
 
 struct mlx5_var_table {
        struct mlx5_var_region var_region;
+       struct mlx5_var_region tlp_var_region;
 };
 
 struct mlx5_port_caps {