[PATCH net-next v2 07/10] mlx4: Register mlx4 devices to an auxiliary virtual bus

From: Petr Pavlu
Date: Sun Aug 13 2023 - 10:52:41 EST


Add an auxiliary virtual bus to model the mlx4 driver structure. The
code is added along the current custom device management logic.
Subsequent patches switch mlx4_en and mlx4_ib to the auxiliary bus and
the old interface is then removed.

Structure mlx4_priv gains a new adev dynamic array to keep track of its
auxiliary devices. Access to the array is protected by the global
mlx4_intf mutex.

Functions mlx4_register_device() and mlx4_unregister_device() are
updated to expose auxiliary devices on the bus in order to load mlx4_en
and/or mlx4_ib. Functions mlx4_register_auxiliary_driver() and
mlx4_unregister_auxiliary_driver() are added to substitute
mlx4_register_interface() and mlx4_unregister_interface(), respectively.
Function mlx4_do_bond() is adjusted to walk over the adev array and
re-adds a specific auxiliary device if its driver sets the
MLX4_INTFF_BONDING flag.

Signed-off-by: Petr Pavlu <petr.pavlu@xxxxxxxx>
Tested-by: Leon Romanovsky <leonro@xxxxxxxxxx>
Reviewed-by: Leon Romanovsky <leonro@xxxxxxxxxx>
Acked-by: Tariq Toukan <tariqt@xxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlx4/Kconfig | 1 +
drivers/net/ethernet/mellanox/mlx4/intf.c | 230 ++++++++++++++++++++-
drivers/net/ethernet/mellanox/mlx4/main.c | 17 +-
drivers/net/ethernet/mellanox/mlx4/mlx4.h | 6 +
include/linux/mlx4/device.h | 7 +
include/linux/mlx4/driver.h | 11 +
6 files changed, 268 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/Kconfig b/drivers/net/ethernet/mellanox/mlx4/Kconfig
index 1b4b1f642317..825e05fb8607 100644
--- a/drivers/net/ethernet/mellanox/mlx4/Kconfig
+++ b/drivers/net/ethernet/mellanox/mlx4/Kconfig
@@ -27,6 +27,7 @@ config MLX4_EN_DCB
config MLX4_CORE
tristate
depends on PCI
+ select AUXILIARY_BUS
select NET_DEVLINK
default n

diff --git a/drivers/net/ethernet/mellanox/mlx4/intf.c b/drivers/net/ethernet/mellanox/mlx4/intf.c
index 30aead34ce08..4b1e18e4a682 100644
--- a/drivers/net/ethernet/mellanox/mlx4/intf.c
+++ b/drivers/net/ethernet/mellanox/mlx4/intf.c
@@ -48,6 +48,89 @@ struct mlx4_device_context {
static LIST_HEAD(intf_list);
static LIST_HEAD(dev_list);
static DEFINE_MUTEX(intf_mutex);
+static DEFINE_IDA(mlx4_adev_ida);
+
+static const struct mlx4_adev_device {
+ const char *suffix;
+ bool (*is_supported)(struct mlx4_dev *dev);
+} mlx4_adev_devices[1] = {};
+
+int mlx4_adev_init(struct mlx4_dev *dev)
+{
+ struct mlx4_priv *priv = mlx4_priv(dev);
+
+ priv->adev_idx = ida_alloc(&mlx4_adev_ida, GFP_KERNEL);
+ if (priv->adev_idx < 0)
+ return priv->adev_idx;
+
+ priv->adev = kcalloc(ARRAY_SIZE(mlx4_adev_devices),
+ sizeof(struct mlx4_adev *), GFP_KERNEL);
+ if (!priv->adev) {
+ ida_free(&mlx4_adev_ida, priv->adev_idx);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+void mlx4_adev_cleanup(struct mlx4_dev *dev)
+{
+ struct mlx4_priv *priv = mlx4_priv(dev);
+
+ kfree(priv->adev);
+ ida_free(&mlx4_adev_ida, priv->adev_idx);
+}
+
+static void adev_release(struct device *dev)
+{
+ struct mlx4_adev *mlx4_adev =
+ container_of(dev, struct mlx4_adev, adev.dev);
+ struct mlx4_priv *priv = mlx4_priv(mlx4_adev->mdev);
+ int idx = mlx4_adev->idx;
+
+ kfree(mlx4_adev);
+ priv->adev[idx] = NULL;
+}
+
+static struct mlx4_adev *add_adev(struct mlx4_dev *dev, int idx)
+{
+ struct mlx4_priv *priv = mlx4_priv(dev);
+ const char *suffix = mlx4_adev_devices[idx].suffix;
+ struct auxiliary_device *adev;
+ struct mlx4_adev *madev;
+ int ret;
+
+ madev = kzalloc(sizeof(*madev), GFP_KERNEL);
+ if (!madev)
+ return ERR_PTR(-ENOMEM);
+
+ adev = &madev->adev;
+ adev->id = priv->adev_idx;
+ adev->name = suffix;
+ adev->dev.parent = &dev->persist->pdev->dev;
+ adev->dev.release = adev_release;
+ madev->mdev = dev;
+ madev->idx = idx;
+
+ ret = auxiliary_device_init(adev);
+ if (ret) {
+ kfree(madev);
+ return ERR_PTR(ret);
+ }
+
+ ret = auxiliary_device_add(adev);
+ if (ret) {
+ auxiliary_device_uninit(adev);
+ return ERR_PTR(ret);
+ }
+ return madev;
+}
+
+static void del_adev(struct auxiliary_device *adev)
+{
+ auxiliary_device_delete(adev);
+ auxiliary_device_uninit(adev);
+}

static void mlx4_add_device(struct mlx4_interface *intf, struct mlx4_priv *priv)
{
@@ -120,12 +203,24 @@ void mlx4_unregister_interface(struct mlx4_interface *intf)
}
EXPORT_SYMBOL_GPL(mlx4_unregister_interface);

+int mlx4_register_auxiliary_driver(struct mlx4_adrv *madrv)
+{
+ return auxiliary_driver_register(&madrv->adrv);
+}
+EXPORT_SYMBOL_GPL(mlx4_register_auxiliary_driver);
+
+void mlx4_unregister_auxiliary_driver(struct mlx4_adrv *madrv)
+{
+ auxiliary_driver_unregister(&madrv->adrv);
+}
+EXPORT_SYMBOL_GPL(mlx4_unregister_auxiliary_driver);
+
int mlx4_do_bond(struct mlx4_dev *dev, bool enable)
{
struct mlx4_priv *priv = mlx4_priv(dev);
struct mlx4_device_context *dev_ctx = NULL, *temp_dev_ctx;
unsigned long flags;
- int ret;
+ int i, ret;
LIST_HEAD(bond_list);

if (!(dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_PORT_REMAP))
@@ -177,6 +272,57 @@ int mlx4_do_bond(struct mlx4_dev *dev, bool enable)
dev_ctx->intf->protocol, enable ?
"enabled" : "disabled");
}
+
+ mutex_lock(&intf_mutex);
+
+ for (i = 0; i < ARRAY_SIZE(mlx4_adev_devices); i++) {
+ struct mlx4_adev *madev = priv->adev[i];
+ struct mlx4_adrv *madrv;
+ enum mlx4_protocol protocol;
+
+ if (!madev)
+ continue;
+
+ device_lock(&madev->adev.dev);
+ if (!madev->adev.dev.driver) {
+ device_unlock(&madev->adev.dev);
+ continue;
+ }
+
+ madrv = container_of(madev->adev.dev.driver, struct mlx4_adrv,
+ adrv.driver);
+ if (!(madrv->flags & MLX4_INTFF_BONDING)) {
+ device_unlock(&madev->adev.dev);
+ continue;
+ }
+
+ if (mlx4_is_mfunc(dev)) {
+ mlx4_dbg(dev,
+ "SRIOV, disabled HA mode for intf proto %d\n",
+ madrv->protocol);
+ device_unlock(&madev->adev.dev);
+ continue;
+ }
+
+ protocol = madrv->protocol;
+ device_unlock(&madev->adev.dev);
+
+ del_adev(&madev->adev);
+ priv->adev[i] = add_adev(dev, i);
+ if (IS_ERR(priv->adev[i])) {
+ mlx4_warn(dev, "Device[%d] (%s) failed to load\n", i,
+ mlx4_adev_devices[i].suffix);
+ priv->adev[i] = NULL;
+ continue;
+ }
+
+ mlx4_dbg(dev,
+ "Interface for protocol %d restarted with bonded mode %s\n",
+ protocol, enable ? "enabled" : "disabled");
+ }
+
+ mutex_unlock(&intf_mutex);
+
return 0;
}

@@ -206,10 +352,80 @@ int mlx4_unregister_event_notifier(struct mlx4_dev *dev,
}
EXPORT_SYMBOL(mlx4_unregister_event_notifier);

+static int add_drivers(struct mlx4_dev *dev)
+{
+ struct mlx4_priv *priv = mlx4_priv(dev);
+ int i, ret = 0;
+
+ for (i = 0; i < ARRAY_SIZE(mlx4_adev_devices); i++) {
+ bool is_supported = false;
+
+ if (priv->adev[i])
+ continue;
+
+ if (mlx4_adev_devices[i].is_supported)
+ is_supported = mlx4_adev_devices[i].is_supported(dev);
+
+ if (!is_supported)
+ continue;
+
+ priv->adev[i] = add_adev(dev, i);
+ if (IS_ERR(priv->adev[i])) {
+ mlx4_warn(dev, "Device[%d] (%s) failed to load\n", i,
+ mlx4_adev_devices[i].suffix);
+ /* We continue to rescan drivers and leave to the caller
+ * to make decision if to release everything or
+ * continue. */
+ ret = PTR_ERR(priv->adev[i]);
+ priv->adev[i] = NULL;
+ }
+ }
+ return ret;
+}
+
+static void delete_drivers(struct mlx4_dev *dev)
+{
+ struct mlx4_priv *priv = mlx4_priv(dev);
+ bool delete_all;
+ int i;
+
+ delete_all = !(dev->persist->interface_state & MLX4_INTERFACE_STATE_UP);
+
+ for (i = ARRAY_SIZE(mlx4_adev_devices) - 1; i >= 0; i--) {
+ bool is_supported = false;
+
+ if (!priv->adev[i])
+ continue;
+
+ if (mlx4_adev_devices[i].is_supported && !delete_all)
+ is_supported = mlx4_adev_devices[i].is_supported(dev);
+
+ if (is_supported)
+ continue;
+
+ del_adev(&priv->adev[i]->adev);
+ priv->adev[i] = NULL;
+ }
+}
+
+/* This function is used after mlx4_dev is reconfigured.
+ */
+static int rescan_drivers_locked(struct mlx4_dev *dev)
+{
+ lockdep_assert_held(&intf_mutex);
+
+ delete_drivers(dev);
+ if (!(dev->persist->interface_state & MLX4_INTERFACE_STATE_UP))
+ return 0;
+
+ return add_drivers(dev);
+}
+
int mlx4_register_device(struct mlx4_dev *dev)
{
struct mlx4_priv *priv = mlx4_priv(dev);
struct mlx4_interface *intf;
+ int ret;

mutex_lock(&intf_mutex);

@@ -218,10 +434,18 @@ int mlx4_register_device(struct mlx4_dev *dev)
list_for_each_entry(intf, &intf_list, list)
mlx4_add_device(intf, priv);

+ ret = rescan_drivers_locked(dev);
+
mutex_unlock(&intf_mutex);
+
+ if (ret) {
+ mlx4_unregister_device(dev);
+ return ret;
+ }
+
mlx4_start_catas_poll(dev);

- return 0;
+ return ret;
}

void mlx4_unregister_device(struct mlx4_dev *dev)
@@ -253,6 +477,8 @@ void mlx4_unregister_device(struct mlx4_dev *dev)
list_del(&priv->dev_list);
dev->persist->interface_state &= ~MLX4_INTERFACE_STATE_UP;

+ rescan_drivers_locked(dev);
+
mutex_unlock(&intf_mutex);
}

diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index 0ed490b99163..c4ec7377aa71 100644
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -3429,6 +3429,10 @@ static int mlx4_load_one(struct pci_dev *pdev, int pci_dev_data,
INIT_LIST_HEAD(&priv->ctx_list);
spin_lock_init(&priv->ctx_lock);

+ err = mlx4_adev_init(dev);
+ if (err)
+ return err;
+
ATOMIC_INIT_NOTIFIER_HEAD(&priv->event_nh);

mutex_init(&priv->port_mutex);
@@ -3455,10 +3459,11 @@ static int mlx4_load_one(struct pci_dev *pdev, int pci_dev_data,
err = mlx4_get_ownership(dev);
if (err) {
if (err < 0)
- return err;
+ goto err_adev;
else {
mlx4_warn(dev, "Multiple PFs not yet supported - Skipping PF\n");
- return -EINVAL;
+ err = -EINVAL;
+ goto err_adev;
}
}

@@ -3806,6 +3811,9 @@ static int mlx4_load_one(struct pci_dev *pdev, int pci_dev_data,
mlx4_free_ownership(dev);

kfree(dev_cap);
+
+err_adev:
+ mlx4_adev_cleanup(dev);
return err;
}

@@ -4186,6 +4194,8 @@ static void mlx4_unload_one(struct pci_dev *pdev)
mlx4_slave_destroy_special_qp_cap(dev);
kfree(dev->dev_vfs);

+ mlx4_adev_cleanup(dev);
+
mlx4_clean_dev(dev);
priv->pci_dev_data = pci_dev_data;
priv->removed = 1;
@@ -4573,6 +4583,9 @@ static int __init mlx4_init(void)
{
int ret;

+ WARN_ONCE(strcmp(MLX4_ADEV_NAME, KBUILD_MODNAME),
+ "mlx4_core name not in sync with kernel module name");
+
if (mlx4_verify_params())
return -EINVAL;

diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4.h b/drivers/net/ethernet/mellanox/mlx4/mlx4.h
index ece9acb6a869..d5050bfb342f 100644
--- a/drivers/net/ethernet/mellanox/mlx4/mlx4.h
+++ b/drivers/net/ethernet/mellanox/mlx4/mlx4.h
@@ -47,6 +47,7 @@
#include <linux/spinlock.h>
#include <net/devlink.h>
#include <linux/rwsem.h>
+#include <linux/auxiliary_bus.h>
#include <linux/notifier.h>

#include <linux/mlx4/device.h>
@@ -884,6 +885,8 @@ struct mlx4_priv {
struct list_head dev_list;
struct list_head ctx_list;
spinlock_t ctx_lock;
+ struct mlx4_adev **adev;
+ int adev_idx;
struct atomic_notifier_head event_nh;

int pci_dev_data;
@@ -1052,6 +1055,9 @@ void mlx4_catas_end(struct mlx4_dev *dev);
int mlx4_crdump_init(struct mlx4_dev *dev);
void mlx4_crdump_end(struct mlx4_dev *dev);
int mlx4_restart_one(struct pci_dev *pdev);
+
+int mlx4_adev_init(struct mlx4_dev *dev);
+void mlx4_adev_cleanup(struct mlx4_dev *dev);
int mlx4_register_device(struct mlx4_dev *dev);
void mlx4_unregister_device(struct mlx4_dev *dev);
void mlx4_dispatch_event(struct mlx4_dev *dev, enum mlx4_dev_event type,
diff --git a/include/linux/mlx4/device.h b/include/linux/mlx4/device.h
index 049d8a4b044d..27f42f713c89 100644
--- a/include/linux/mlx4/device.h
+++ b/include/linux/mlx4/device.h
@@ -33,6 +33,7 @@
#ifndef MLX4_DEVICE_H
#define MLX4_DEVICE_H

+#include <linux/auxiliary_bus.h>
#include <linux/if_ether.h>
#include <linux/pci.h>
#include <linux/completion.h>
@@ -889,6 +890,12 @@ struct mlx4_dev {
u8 uar_page_shift;
};

+struct mlx4_adev {
+ struct auxiliary_device adev;
+ struct mlx4_dev *mdev;
+ int idx;
+};
+
struct mlx4_clock_params {
u64 offset;
u8 bar;
diff --git a/include/linux/mlx4/driver.h b/include/linux/mlx4/driver.h
index 781d5a0c2faa..9cf157d381c6 100644
--- a/include/linux/mlx4/driver.h
+++ b/include/linux/mlx4/driver.h
@@ -34,9 +34,12 @@
#define MLX4_DRIVER_H

#include <net/devlink.h>
+#include <linux/auxiliary_bus.h>
#include <linux/notifier.h>
#include <linux/mlx4/device.h>

+#define MLX4_ADEV_NAME "mlx4_core"
+
struct mlx4_dev;

#define MLX4_MAC_MASK 0xffffffffffffULL
@@ -63,8 +66,16 @@ struct mlx4_interface {
int flags;
};

+struct mlx4_adrv {
+ struct auxiliary_driver adrv;
+ enum mlx4_protocol protocol;
+ int flags;
+};
+
int mlx4_register_interface(struct mlx4_interface *intf);
void mlx4_unregister_interface(struct mlx4_interface *intf);
+int mlx4_register_auxiliary_driver(struct mlx4_adrv *madrv);
+void mlx4_unregister_auxiliary_driver(struct mlx4_adrv *madrv);

int mlx4_register_event_notifier(struct mlx4_dev *dev,
struct notifier_block *nb);
--
2.35.3