mlx5: Support fast teardown over vfio

Add vfio fast teardown support; If it fails then do regular teardown. Signed-off-by: Mark Zhang <[email protected]> Signed-off-by: Yishai Hadas <[email protected]>
linux-rdma · Jul 29, 2021 · 00a5b51 · 00a5b51
1 parent 7ea5d01
commit 00a5b51
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diff --git a/providers/mlx5/mlx5_ifc.h b/providers/mlx5/mlx5_ifc.h
@@ -4289,6 +4289,10 @@ struct mlx5_ifc_manage_pages_in_bits {
  u8 pas[][0x40];
 };
 
+enum {
+ MLX5_TEARDOWN_HCA_OUT_FORCE_STATE_FAIL = 0x1,
+};
+
 struct mlx5_ifc_teardown_hca_out_bits {
  u8 status[0x8];
  u8 reserved_at_8[0x18];
@@ -4302,6 +4306,7 @@ struct mlx5_ifc_teardown_hca_out_bits {
 
 enum {
  MLX5_TEARDOWN_HCA_IN_PROFILE_GRACEFUL_CLOSE = 0x0,
+ MLX5_TEARDOWN_HCA_IN_PROFILE_PREPARE_FAST_TEARDOWN = 0x2,
 };
 
 struct mlx5_ifc_teardown_hca_in_bits {

diff --git a/providers/mlx5/mlx5_vfio.c b/providers/mlx5/mlx5_vfio.c
@@ -1351,7 +1351,7 @@ static int wait_fw_init(struct mlx5_init_seg *init_seg, uint32_t max_wait_mili)
  return 0;
 }
 
-static int mlx5_vfio_teardown_hca(struct mlx5_vfio_context *ctx)
+static int mlx5_vfio_teardown_hca_regular(struct mlx5_vfio_context *ctx)
 {
  uint32_t in[DEVX_ST_SZ_DW(teardown_hca_in)] = {};
  uint32_t out[DEVX_ST_SZ_DW(teardown_hca_out)] = {};
@@ -1361,6 +1361,80 @@ static int mlx5_vfio_teardown_hca(struct mlx5_vfio_context *ctx)
  return mlx5_vfio_cmd_exec(ctx, in, sizeof(in), out, sizeof(out), 0);
 }
 
+enum mlx5_cmd_addr_l_sz_offset {
+ MLX5_NIC_IFC_OFFSET = 8,
+};
+
+enum {
+ MLX5_NIC_IFC_DISABLED = 1,
+};
+
+static uint8_t mlx5_vfio_get_nic_state(struct mlx5_vfio_context *ctx)
+{
+ return (be32toh(mmio_read32_be(&ctx->bar_map->cmdq_addr_l_sz)) >> 8) & 7;
+}
+
+static void mlx5_vfio_set_nic_state(struct mlx5_vfio_context *ctx, uint8_t state)
+{
+ uint32_t cur_cmdq_addr_l_sz;
+
+ cur_cmdq_addr_l_sz = be32toh(mmio_read32_be(&ctx->bar_map->cmdq_addr_l_sz));
+ mmio_write32_be(&ctx->bar_map->cmdq_addr_l_sz,
+ htobe32((cur_cmdq_addr_l_sz & 0xFFFFF000) |
+ state << MLX5_NIC_IFC_OFFSET));
+}
+
+#define MLX5_FAST_TEARDOWN_WAIT_MS 3000
+#define MLX5_FAST_TEARDOWN_WAIT_ONCE_MS 1
+static int mlx5_vfio_teardown_hca_fast(struct mlx5_vfio_context *ctx)
+{
+ uint32_t out[DEVX_ST_SZ_DW(teardown_hca_out)] = {};
+ uint32_t in[DEVX_ST_SZ_DW(teardown_hca_in)] = {};
+ int waited = 0, state, ret;
+
+ DEVX_SET(teardown_hca_in, in, opcode, MLX5_CMD_OP_TEARDOWN_HCA);
+ DEVX_SET(teardown_hca_in, in, profile,
+ MLX5_TEARDOWN_HCA_IN_PROFILE_PREPARE_FAST_TEARDOWN);
+ ret = mlx5_vfio_cmd_exec(ctx, in, sizeof(in), out, sizeof(out), 0);
+ if (ret)
+ return ret;
+
+ state = DEVX_GET(teardown_hca_out, out, state);
+ if (state == MLX5_TEARDOWN_HCA_OUT_FORCE_STATE_FAIL) {
+ mlx5_err(ctx->dbg_fp, "teardown with fast mode failed\n");
+ return EIO;
+ }
+
+ mlx5_vfio_set_nic_state(ctx, MLX5_NIC_IFC_DISABLED);
+ do {
+ if (mlx5_vfio_get_nic_state(ctx) == MLX5_NIC_IFC_DISABLED)
+ break;
+ usleep(MLX5_FAST_TEARDOWN_WAIT_ONCE_MS * 1000);
+ waited += MLX5_FAST_TEARDOWN_WAIT_ONCE_MS;
+ } while (waited < MLX5_FAST_TEARDOWN_WAIT_MS);
+
+ if (mlx5_vfio_get_nic_state(ctx) != MLX5_NIC_IFC_DISABLED) {
+ mlx5_err(ctx->dbg_fp, "NIC IFC still %d after %ums.\n",
+ mlx5_vfio_get_nic_state(ctx), waited);
+ return EIO;
+ }
+
+ return 0;
+}
+
+static int mlx5_vfio_teardown_hca(struct mlx5_vfio_context *ctx)
+{
+ int err;
+
+ if (MLX5_VFIO_CAP_GEN(ctx, fast_teardown)) {
+ err = mlx5_vfio_teardown_hca_fast(ctx);
+ if (!err)
+ return 0;
+ }
+
+ return mlx5_vfio_teardown_hca_regular(ctx);
+}
+
 static int mlx5_vfio_setup_function(struct mlx5_vfio_context *ctx)
 {
  int err;