[PATCH mlx5-next 01/10] RDMA/mlx5: Notify data direct users via a notifier chain on unbind
From: Tariq Toukan
Date: Thu Sep 17 2026 - 07:24:41 EST
From: Dragos Tatulea <dtatulea@xxxxxxxxxx>
Currently during unbind, data direct code calls
mlx5_ib_data_direct_unbind() directly. To make the unbind notification
generic and support multiple users, deliver an MLX5_DATA_DIRECT_UNBIND
event through a blocking_notifier chain kept per registration.
Users register a notifier_block via mlx5_data_direct_ib_reg(); mlx5_ib
embeds one in struct mlx5_ib_dev and, from its notifier callback, runs
the existing mlx5_ib_data_direct_unbind() teardown.
This patch doesn't introduce any functional changes.
Signed-off-by: Dragos Tatulea <dtatulea@xxxxxxxxxx>
Reviewed-by: Cosmin Ratiu <cratiu@xxxxxxxxxx>
Reviewed-by: Leon Romanovsky <leonro@xxxxxxxxxx>
Signed-off-by: Tariq Toukan <tariqt@xxxxxxxxxx>
---
drivers/infiniband/hw/mlx5/data_direct.c | 17 ++++++++++++++---
drivers/infiniband/hw/mlx5/data_direct.h | 12 ++++++++++--
drivers/infiniband/hw/mlx5/main.c | 17 +++++++++++++++--
drivers/infiniband/hw/mlx5/mlx5_ib.h | 1 +
4 files changed, 40 insertions(+), 7 deletions(-)
diff --git a/drivers/infiniband/hw/mlx5/data_direct.c b/drivers/infiniband/hw/mlx5/data_direct.c
index d57484245c38..04affdbdcb12 100644
--- a/drivers/infiniband/hw/mlx5/data_direct.c
+++ b/drivers/infiniband/hw/mlx5/data_direct.c
@@ -4,6 +4,9 @@
*/
#include "mlx5_ib.h"
+
+#include <linux/notifier.h>
+
#include "data_direct.h"
static LIST_HEAD(mlx5_data_direct_dev_list);
@@ -18,6 +21,7 @@ struct mlx5_data_direct_registration {
struct mlx5_ib_dev *ibdev;
char vuid[MLX5_ST_SZ_BYTES(array1024_auto) + 1];
struct list_head list;
+ struct blocking_notifier_head users;
};
static const struct pci_device_id mlx5_data_direct_pci_table[] = {
@@ -78,7 +82,8 @@ static int mlx5_data_direct_set_dma_caps(struct pci_dev *pdev)
return 0;
}
-int mlx5_data_direct_ib_reg(struct mlx5_ib_dev *ibdev, char *vuid)
+int mlx5_data_direct_ib_reg(struct mlx5_ib_dev *ibdev, char *vuid,
+ struct notifier_block *nb)
{
struct mlx5_data_direct_registration *reg;
struct mlx5_data_direct_dev *dev;
@@ -89,6 +94,8 @@ int mlx5_data_direct_ib_reg(struct mlx5_ib_dev *ibdev, char *vuid)
reg->ibdev = ibdev;
strscpy(reg->vuid, vuid);
+ BLOCKING_INIT_NOTIFIER_HEAD(®->users);
+ blocking_notifier_chain_register(®->users, nb);
mutex_lock(&mlx5_data_direct_mutex);
list_for_each_entry(dev, &mlx5_data_direct_dev_list, list) {
@@ -106,13 +113,15 @@ int mlx5_data_direct_ib_reg(struct mlx5_ib_dev *ibdev, char *vuid)
return 0;
}
-void mlx5_data_direct_ib_unreg(struct mlx5_ib_dev *ibdev)
+void mlx5_data_direct_ib_unreg(struct mlx5_ib_dev *ibdev,
+ struct notifier_block *nb)
{
struct mlx5_data_direct_registration *reg;
mutex_lock(&mlx5_data_direct_mutex);
list_for_each_entry(reg, &mlx5_data_direct_reg_list, list) {
if (reg->ibdev == ibdev) {
+ blocking_notifier_chain_unregister(®->users, nb);
list_del(®->list);
kfree(reg);
goto end;
@@ -150,7 +159,9 @@ static void mlx5_data_direct_dev_unreg(struct mlx5_data_direct_dev *dev)
list_del(&dev->list);
list_for_each_entry(reg, &mlx5_data_direct_reg_list, list) {
if (strcmp(dev->vuid, reg->vuid) == 0)
- mlx5_ib_data_direct_unbind(reg->ibdev);
+ blocking_notifier_call_chain(®->users,
+ MLX5_DATA_DIRECT_UNBIND,
+ NULL);
}
mutex_unlock(&mlx5_data_direct_mutex);
}
diff --git a/drivers/infiniband/hw/mlx5/data_direct.h b/drivers/infiniband/hw/mlx5/data_direct.h
index 2fd2bdbe8f69..a9bb471949e2 100644
--- a/drivers/infiniband/hw/mlx5/data_direct.h
+++ b/drivers/infiniband/hw/mlx5/data_direct.h
@@ -6,8 +6,14 @@
#ifndef _MLX5_IB_DATA_DIRECT_H
#define _MLX5_IB_DATA_DIRECT_H
+#include <linux/notifier.h>
+
struct mlx5_ib_dev;
+enum mlx5_data_direct_event {
+ MLX5_DATA_DIRECT_UNBIND,
+};
+
struct mlx5_data_direct_dev {
struct device *device;
struct pci_dev *pdev;
@@ -15,8 +21,10 @@ struct mlx5_data_direct_dev {
struct list_head list;
};
-int mlx5_data_direct_ib_reg(struct mlx5_ib_dev *ibdev, char *vuid);
-void mlx5_data_direct_ib_unreg(struct mlx5_ib_dev *ibdev);
+int mlx5_data_direct_ib_reg(struct mlx5_ib_dev *ibdev, char *vuid,
+ struct notifier_block *nb);
+void mlx5_data_direct_ib_unreg(struct mlx5_ib_dev *ibdev,
+ struct notifier_block *nb);
int mlx5_data_direct_driver_register(void);
void mlx5_data_direct_driver_unregister(void);
diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index 02809114fc79..547275dfa40e 100644
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -4019,6 +4019,18 @@ static bool mlx5_ib_bind_slave_port(struct mlx5_ib_dev *ibdev,
return false;
}
+static int mlx5_ib_data_direct_event(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct mlx5_ib_dev *dev =
+ container_of(nb, struct mlx5_ib_dev, data_direct_nb);
+
+ if (action == MLX5_DATA_DIRECT_UNBIND)
+ mlx5_ib_data_direct_unbind(dev);
+
+ return NOTIFY_OK;
+}
+
static int mlx5_ib_data_direct_init(struct mlx5_ib_dev *dev)
{
char vuid[MLX5_ST_SZ_BYTES(array1024_auto) + 1] = {};
@@ -4037,7 +4049,8 @@ static int mlx5_ib_data_direct_init(struct mlx5_ib_dev *dev)
return ret;
INIT_LIST_HEAD(&dev->data_direct_mr_list);
- ret = mlx5_data_direct_ib_reg(dev, vuid);
+ dev->data_direct_nb.notifier_call = mlx5_ib_data_direct_event;
+ ret = mlx5_data_direct_ib_reg(dev, vuid, &dev->data_direct_nb);
if (ret)
mlx5_ib_free_data_direct_resources(dev);
@@ -4050,7 +4063,7 @@ static void mlx5_ib_data_direct_cleanup(struct mlx5_ib_dev *dev)
!MLX5_CAP_GEN_2(dev->mdev, query_vuid))
return;
- mlx5_data_direct_ib_unreg(dev);
+ mlx5_data_direct_ib_unreg(dev, &dev->data_direct_nb);
mlx5_ib_free_data_direct_resources(dev);
}
diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h
index 522984d958bb..97d2aa79e95d 100644
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -1131,6 +1131,7 @@ struct mlx5_ib_dev {
spinlock_t reset_flow_resource_lock;
struct list_head qp_list;
struct list_head data_direct_mr_list;
+ struct notifier_block data_direct_nb;
/* Array with num_ports elements */
struct mlx5_ib_port *port;
struct mlx5_sq_bfreg bfreg;
--
2.44.0