net/mlx5: Free IRQs in shutdown path

Some platforms require IRQs to be free'd in the shutdown path. Otherwise
they will fail to be reallocated after a kexec.

Fixes: 8812c24 ("net/mlx5: Add fast unload support in shutdown flow")
Signed-off-by: Daniel Jurgens <[email protected]>
Signed-off-by: Saeed Mahameed <[email protected]>

Author: Daniel Jurgens

drivers/net/ethernet/mellanox/mlx5/core/eq.c

@@ -34,6 +34,9 @@
 #include <linux/module.h>
 #include <linux/mlx5/driver.h>
 #include <linux/mlx5/cmd.h>
+#ifdef CONFIG_RFS_ACCEL
+#include <linux/cpu_rmap.h>
+#endif
 #include "mlx5_core.h"
 #include "fpga/core.h"
 #include "eswitch.h"
@@ -923,3 +926,28 @@ int mlx5_core_eq_query(struct mlx5_core_dev *dev, struct mlx5_eq *eq,
 	MLX5_SET(query_eq_in, in, eq_number, eq->eqn);
 	return mlx5_cmd_exec(dev, in, sizeof(in), out, outlen);
 }
+
+/* This function should only be called after mlx5_cmd_force_teardown_hca */
+void mlx5_core_eq_free_irqs(struct mlx5_core_dev *dev)
+{
+	struct mlx5_eq_table *table = &dev->priv.eq_table;
+	struct mlx5_eq *eq;
+
+#ifdef CONFIG_RFS_ACCEL
+	if (dev->rmap) {
+		free_irq_cpu_rmap(dev->rmap);
+		dev->rmap = NULL;
+	}
+#endif
+	list_for_each_entry(eq, &table->comp_eqs_list, list)
+		free_irq(eq->irqn, eq);
+
+	free_irq(table->pages_eq.irqn, &table->pages_eq);
+	free_irq(table->async_eq.irqn, &table->async_eq);
+	free_irq(table->cmd_eq.irqn, &table->cmd_eq);
+#ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
+	if (MLX5_CAP_GEN(dev, pg))
+		free_irq(table->pfault_eq.irqn, &table->pfault_eq);
+#endif
+	pci_free_irq_vectors(dev->pdev);
+}

drivers/net/ethernet/mellanox/mlx5/core/main.c

@@ -1587,6 +1587,14 @@ static int mlx5_try_fast_unload(struct mlx5_core_dev *dev)
 
 	mlx5_enter_error_state(dev, true);
 
+	/* Some platforms requiring freeing the IRQ's in the shutdown
+	 * flow. If they aren't freed they can't be allocated after
+	 * kexec. There is no need to cleanup the mlx5_core software
+	 * contexts.
+	 */
+	mlx5_irq_clear_affinity_hints(dev);
+	mlx5_core_eq_free_irqs(dev);
+
 	return 0;
 }
 

drivers/net/ethernet/mellanox/mlx5/core/mlx5_core.h

@@ -128,6 +128,8 @@ int mlx5_core_eq_query(struct mlx5_core_dev *dev, struct mlx5_eq *eq,
 		       u32 *out, int outlen);
 int mlx5_start_eqs(struct mlx5_core_dev *dev);
 void mlx5_stop_eqs(struct mlx5_core_dev *dev);
+/* This function should only be called after mlx5_cmd_force_teardown_hca */
+void mlx5_core_eq_free_irqs(struct mlx5_core_dev *dev);
 struct mlx5_eq *mlx5_eqn2eq(struct mlx5_core_dev *dev, int eqn);
 u32 mlx5_eq_poll_irq_disabled(struct mlx5_eq *eq);
 void mlx5_cq_tasklet_cb(unsigned long data);