[patch net-next v2 0/7] devlink: sanitize per-port region creation/destruction

[patch net-next v2 0/7] devlink: sanitize per-port region creation/destruction

[Jiri Pirko]

From: Jiri Pirko <jiri@nvidia.com>

Currently the only user of per-port devlink regions is DSA. All drivers
that use regions register them before devlink registration. For DSA,
this was not possible as the internals of struct devlink_port needed for
region creation are initialized during port registration.

This introduced a mismatch in creation flow of devlink and devlink port
regions. As you can see, it causes the DSA driver to make the port
init/exit flow a bit cumbersome.

Fix this by introducing port_init/fini() which could be optionally
called by drivers like DSA, to prepare struct devlink_port to be used
for region creation purposes before devlink port register is called.

Tested by Vladimir on his setup.

---
v1->v2:
- Netdevsim patch removed and also the patch forcing region creation
  before register was removed.
- Two Vladimir's patches were added.

Jiri Pirko (5):
  net: devlink: introduce port registered assert helper and use it
  net: devlink: introduce a flag to indicate devlink port being
    registered
  net: devlink: add port_init/fini() helpers to allow
    pre-register/post-unregister functions
  net: dsa: move port_setup/teardown to be called outside devlink port
    registered area
  net: dsa: don't do devlink port setup early

Vladimir Oltean (2):
  net: dsa: don't leave dangling pointers in dp->pl when failing
  net: dsa: remove bool devlink_port_setup

 include/net/devlink.h |   7 +-
 include/net/dsa.h     |   2 -
 net/core/devlink.c    |  80 ++++++++++++++----
 net/dsa/dsa2.c        | 184 ++++++++++++++++++------------------------
 net/dsa/dsa_priv.h    |   1 +
 net/dsa/port.c        |  22 +++--
 net/dsa/slave.c       |   6 +-
 7 files changed, 166 insertions(+), 136 deletions(-)

-- 
2.37.1

[patch net-next v2 1/7] net: devlink: introduce port registered assert helper and use it

[Jiri Pirko]

From: Jiri Pirko <jiri@nvidia.com>

Instead of checking devlink_port->devlink pointer for not being NULL
which indicates that devlink port is registered, put this check to new
pair of helpers similar to what we have for devlink and use them in
other functions.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
---
 net/core/devlink.c | 32 +++++++++++++++++++-------------
 1 file changed, 19 insertions(+), 13 deletions(-)

diff --git a/net/core/devlink.c b/net/core/devlink.c
index 7776dc82f88d..f5bfbdb0301e 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -371,6 +371,11 @@ static struct devlink *devlink_get_from_attrs(struct net *net,
 	return ERR_PTR(-ENODEV);
 }
 
+#define ASSERT_DEVLINK_PORT_REGISTERED(devlink_port)				\
+	WARN_ON_ONCE(!(devlink_port)->devlink)
+#define ASSERT_DEVLINK_PORT_NOT_REGISTERED(devlink_port)			\
+	WARN_ON_ONCE((devlink_port)->devlink)
+
 static struct devlink_port *devlink_port_get_by_index(struct devlink *devlink,
 						      unsigned int port_index)
 {
@@ -9869,7 +9874,8 @@ int devl_port_register(struct devlink *devlink,
 	if (devlink_port_index_exists(devlink, port_index))
 		return -EEXIST;
 
-	WARN_ON(devlink_port->devlink);
+	ASSERT_DEVLINK_PORT_NOT_REGISTERED(devlink_port);
+
 	devlink_port->devlink = devlink;
 	devlink_port->index = port_index;
 	spin_lock_init(&devlink_port->type_lock);
@@ -9952,8 +9958,8 @@ static void __devlink_port_type_set(struct devlink_port *devlink_port,
 				    enum devlink_port_type type,
 				    void *type_dev)
 {
-	if (WARN_ON(!devlink_port->devlink))
-		return;
+	ASSERT_DEVLINK_PORT_REGISTERED(devlink_port);
+
 	devlink_port_type_warn_cancel(devlink_port);
 	spin_lock_bh(&devlink_port->type_lock);
 	devlink_port->type = type;
@@ -10072,8 +10078,8 @@ void devlink_port_attrs_set(struct devlink_port *devlink_port,
 {
 	int ret;
 
-	if (WARN_ON(devlink_port->devlink))
-		return;
+	ASSERT_DEVLINK_PORT_NOT_REGISTERED(devlink_port);
+
 	devlink_port->attrs = *attrs;
 	ret = __devlink_port_attrs_set(devlink_port, attrs->flavour);
 	if (ret)
@@ -10096,8 +10102,8 @@ void devlink_port_attrs_pci_pf_set(struct devlink_port *devlink_port, u32 contro
 	struct devlink_port_attrs *attrs = &devlink_port->attrs;
 	int ret;
 
-	if (WARN_ON(devlink_port->devlink))
-		return;
+	ASSERT_DEVLINK_PORT_NOT_REGISTERED(devlink_port);
+
 	ret = __devlink_port_attrs_set(devlink_port,
 				       DEVLINK_PORT_FLAVOUR_PCI_PF);
 	if (ret)
@@ -10123,8 +10129,8 @@ void devlink_port_attrs_pci_vf_set(struct devlink_port *devlink_port, u32 contro
 	struct devlink_port_attrs *attrs = &devlink_port->attrs;
 	int ret;
 
-	if (WARN_ON(devlink_port->devlink))
-		return;
+	ASSERT_DEVLINK_PORT_NOT_REGISTERED(devlink_port);
+
 	ret = __devlink_port_attrs_set(devlink_port,
 				       DEVLINK_PORT_FLAVOUR_PCI_VF);
 	if (ret)
@@ -10151,8 +10157,8 @@ void devlink_port_attrs_pci_sf_set(struct devlink_port *devlink_port, u32 contro
 	struct devlink_port_attrs *attrs = &devlink_port->attrs;
 	int ret;
 
-	if (WARN_ON(devlink_port->devlink))
-		return;
+	ASSERT_DEVLINK_PORT_NOT_REGISTERED(devlink_port);
+
 	ret = __devlink_port_attrs_set(devlink_port,
 				       DEVLINK_PORT_FLAVOUR_PCI_SF);
 	if (ret)
@@ -10267,8 +10273,8 @@ EXPORT_SYMBOL_GPL(devl_rate_nodes_destroy);
 void devlink_port_linecard_set(struct devlink_port *devlink_port,
 			       struct devlink_linecard *linecard)
 {
-	if (WARN_ON(devlink_port->devlink))
-		return;
+	ASSERT_DEVLINK_PORT_NOT_REGISTERED(devlink_port);
+
 	devlink_port->linecard = linecard;
 }
 EXPORT_SYMBOL_GPL(devlink_port_linecard_set);
-- 
2.37.1

[patch net-next v2 2/7] net: devlink: introduce a flag to indicate devlink port being registered

[Jiri Pirko]

From: Jiri Pirko <jiri@nvidia.com>

Instead of relying on devlink pointer not being initialized, introduce
an extra flag to indicate if devlink port is registered. This is needed
as later on devlink pointer is going to be initialized even in case
devlink port is not registered yet.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
---
 include/net/devlink.h | 3 ++-
 net/core/devlink.c    | 6 ++++--
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/include/net/devlink.h b/include/net/devlink.h
index 264aa98e6da6..bcacd8dab297 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -129,7 +129,8 @@ struct devlink_port {
 	void *type_dev;
 	struct devlink_port_attrs attrs;
 	u8 attrs_set:1,
-	   switch_port:1;
+	   switch_port:1,
+	   registered:1;
 	struct delayed_work type_warn_dw;
 	struct list_head reporter_list;
 	struct mutex reporters_lock; /* Protects reporter_list */
diff --git a/net/core/devlink.c b/net/core/devlink.c
index f5bfbdb0301e..17529e6b2bbf 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -372,9 +372,9 @@ static struct devlink *devlink_get_from_attrs(struct net *net,
 }
 
 #define ASSERT_DEVLINK_PORT_REGISTERED(devlink_port)				\
-	WARN_ON_ONCE(!(devlink_port)->devlink)
+	WARN_ON_ONCE(!(devlink_port)->registered)
 #define ASSERT_DEVLINK_PORT_NOT_REGISTERED(devlink_port)			\
-	WARN_ON_ONCE((devlink_port)->devlink)
+	WARN_ON_ONCE((devlink_port)->registered)
 
 static struct devlink_port *devlink_port_get_by_index(struct devlink *devlink,
 						      unsigned int port_index)
@@ -9876,6 +9876,7 @@ int devl_port_register(struct devlink *devlink,
 
 	ASSERT_DEVLINK_PORT_NOT_REGISTERED(devlink_port);
 
+	devlink_port->registered = true;
 	devlink_port->devlink = devlink;
 	devlink_port->index = port_index;
 	spin_lock_init(&devlink_port->type_lock);
@@ -9934,6 +9935,7 @@ void devl_port_unregister(struct devlink_port *devlink_port)
 	WARN_ON(!list_empty(&devlink_port->reporter_list));
 	WARN_ON(!list_empty(&devlink_port->region_list));
 	mutex_destroy(&devlink_port->reporters_lock);
+	devlink_port->registered = false;
 }
 EXPORT_SYMBOL_GPL(devl_port_unregister);
 
-- 
2.37.1

[patch net-next v2 3/7] net: devlink: add port_init/fini() helpers to allow pre-register/post-unregister functions

[Jiri Pirko]

From: Jiri Pirko <jiri@nvidia.com>

To be consistent with devlink regions, devlink port regions are going to
be forbidden to be created once devlink port is registered. Prepare for
this and introduce new set of helpers to allow driver to initialize
devlink pointer and region list before devlink_register() is called
That allows port regions to be created before devlink port registration
and destroyed after devlink port unregistration.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
---
 include/net/devlink.h |  6 +++++-
 net/core/devlink.c    | 46 ++++++++++++++++++++++++++++++++++++++++---
 2 files changed, 48 insertions(+), 4 deletions(-)

diff --git a/include/net/devlink.h b/include/net/devlink.h
index bcacd8dab297..ba6b8b094943 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -130,7 +130,8 @@ struct devlink_port {
 	struct devlink_port_attrs attrs;
 	u8 attrs_set:1,
 	   switch_port:1,
-	   registered:1;
+	   registered:1,
+	   initialized:1;
 	struct delayed_work type_warn_dw;
 	struct list_head reporter_list;
 	struct mutex reporters_lock; /* Protects reporter_list */
@@ -1563,6 +1564,9 @@ void devlink_set_features(struct devlink *devlink, u64 features);
 void devlink_register(struct devlink *devlink);
 void devlink_unregister(struct devlink *devlink);
 void devlink_free(struct devlink *devlink);
+void devlink_port_init(struct devlink *devlink,
+		       struct devlink_port *devlink_port);
+void devlink_port_fini(struct devlink_port *devlink_port);
 int devl_port_register(struct devlink *devlink,
 		       struct devlink_port *devlink_port,
 		       unsigned int port_index);
diff --git a/net/core/devlink.c b/net/core/devlink.c
index 17529e6b2bbf..89baa7c0938b 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -375,6 +375,8 @@ static struct devlink *devlink_get_from_attrs(struct net *net,
 	WARN_ON_ONCE(!(devlink_port)->registered)
 #define ASSERT_DEVLINK_PORT_NOT_REGISTERED(devlink_port)			\
 	WARN_ON_ONCE((devlink_port)->registered)
+#define ASSERT_DEVLINK_PORT_INITIALIZED(devlink_port)				\
+	WARN_ON_ONCE(!(devlink_port)->initialized)
 
 static struct devlink_port *devlink_port_get_by_index(struct devlink *devlink,
 						      unsigned int port_index)
@@ -9852,6 +9854,44 @@ static void devlink_port_type_warn_cancel(struct devlink_port *devlink_port)
 	cancel_delayed_work_sync(&devlink_port->type_warn_dw);
 }
 
+/**
+ * devlink_port_init() - Init devlink port
+ *
+ * @devlink: devlink
+ * @devlink_port: devlink port
+ *
+ * Initialize essencial stuff that is needed for functions
+ * that may be called before devlink port registration.
+ * Call to this function is optional and not needed
+ * in case the driver does not use such functions.
+ */
+void devlink_port_init(struct devlink *devlink,
+		       struct devlink_port *devlink_port)
+{
+	if (devlink_port->initialized)
+		return;
+	devlink_port->devlink = devlink;
+	INIT_LIST_HEAD(&devlink_port->region_list);
+	devlink_port->initialized = true;
+}
+EXPORT_SYMBOL_GPL(devlink_port_init);
+
+/**
+ * devlink_port_fini() - Deinitialize devlink port
+ *
+ * @devlink_port: devlink port
+ *
+ * Deinitialize essencial stuff that is in use for functions
+ * that may be called after devlink port unregistration.
+ * Call to this function is optional and not needed
+ * in case the driver does not use such functions.
+ */
+void devlink_port_fini(struct devlink_port *devlink_port)
+{
+	WARN_ON(!list_empty(&devlink_port->region_list));
+}
+EXPORT_SYMBOL_GPL(devlink_port_fini);
+
 /**
  * devl_port_register() - Register devlink port
  *
@@ -9876,14 +9916,13 @@ int devl_port_register(struct devlink *devlink,
 
 	ASSERT_DEVLINK_PORT_NOT_REGISTERED(devlink_port);
 
+	devlink_port_init(devlink, devlink_port);
 	devlink_port->registered = true;
-	devlink_port->devlink = devlink;
 	devlink_port->index = port_index;
 	spin_lock_init(&devlink_port->type_lock);
 	INIT_LIST_HEAD(&devlink_port->reporter_list);
 	mutex_init(&devlink_port->reporters_lock);
 	list_add_tail(&devlink_port->list, &devlink->port_list);
-	INIT_LIST_HEAD(&devlink_port->region_list);
 
 	INIT_DELAYED_WORK(&devlink_port->type_warn_dw, &devlink_port_type_warn);
 	devlink_port_type_warn_schedule(devlink_port);
@@ -9933,7 +9972,6 @@ void devl_port_unregister(struct devlink_port *devlink_port)
 	devlink_port_notify(devlink_port, DEVLINK_CMD_PORT_DEL);
 	list_del(&devlink_port->list);
 	WARN_ON(!list_empty(&devlink_port->reporter_list));
-	WARN_ON(!list_empty(&devlink_port->region_list));
 	mutex_destroy(&devlink_port->reporters_lock);
 	devlink_port->registered = false;
 }
@@ -11347,6 +11385,8 @@ devlink_port_region_create(struct devlink_port *port,
 	struct devlink_region *region;
 	int err = 0;
 
+	ASSERT_DEVLINK_PORT_INITIALIZED(port);
+
 	if (WARN_ON(!ops) || WARN_ON(!ops->destructor))
 		return ERR_PTR(-EINVAL);
 
-- 
2.37.1

Re: [patch net-next v2 3/7] net: devlink: add port_init/fini() helpers to allow pre-register/post-unregister functions

[Jakub Kicinski]

On Tue, 27 Sep 2022 09:56:41 +0200 Jiri Pirko wrote:
> To be consistent with devlink regions, devlink port regions are going to
> be forbidden to be created once devlink port is registered. Prepare for
> this and introduce new set of helpers to allow driver to initialize
> devlink pointer and region list before devlink_register() is called
> That allows port regions to be created before devlink port registration
> and destroyed after devlink port unregistration.

The patches look good but I think the commit message needs an update,
no?  We no longer plan to forbid the late registration IIRC.

Re: [patch net-next v2 3/7] net: devlink: add port_init/fini() helpers to allow pre-register/post-unregister functions

[Jiri Pirko]

Wed, Sep 28, 2022 at 03:10:41AM CEST, kuba@kernel.org wrote:
>On Tue, 27 Sep 2022 09:56:41 +0200 Jiri Pirko wrote:
>> To be consistent with devlink regions, devlink port regions are going to
>> be forbidden to be created once devlink port is registered. Prepare for
>> this and introduce new set of helpers to allow driver to initialize
>> devlink pointer and region list before devlink_register() is called
>> That allows port regions to be created before devlink port registration
>> and destroyed after devlink port unregistration.
>
>The patches look good but I think the commit message needs an update,
>no?  We no longer plan to forbid the late registration IIRC.

Ah, yeah, leftover. Let me send v3 with this fixed.

[patch net-next v2 4/7] net: dsa: move port_setup/teardown to be called outside devlink port registered area

[Jiri Pirko]

From: Jiri Pirko <jiri@nvidia.com>

Move port_setup() op to be called before devlink_port_register() and
port_teardown() after devlink_port_unregister().

Note it makes sense to move this alongside the rest of the devlink port
code, the reinit() function also gets much nicer, as clearly the fact that
port_setup()->devlink_port_region_create() was called in dsa_port_setup
did not fit the flow.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
---
 net/dsa/dsa2.c | 68 +++++++++++++++++++-------------------------------
 1 file changed, 26 insertions(+), 42 deletions(-)

diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index 7024e2120de1..6f555b1bb483 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -472,12 +472,6 @@ static int dsa_port_setup(struct dsa_port *dp)
 	if (dp->setup)
 		return 0;
 
-	if (ds->ops->port_setup) {
-		err = ds->ops->port_setup(ds, dp->index);
-		if (err)
-			return err;
-	}
-
 	switch (dp->type) {
 	case DSA_PORT_TYPE_UNUSED:
 		dsa_port_disable(dp);
@@ -532,11 +526,8 @@ static int dsa_port_setup(struct dsa_port *dp)
 		dsa_port_disable(dp);
 	if (err && dsa_port_link_registered)
 		dsa_shared_port_link_unregister_of(dp);
-	if (err) {
-		if (ds->ops->port_teardown)
-			ds->ops->port_teardown(ds, dp->index);
+	if (err)
 		return err;
-	}
 
 	dp->setup = true;
 
@@ -549,17 +540,26 @@ static int dsa_port_devlink_setup(struct dsa_port *dp)
 	struct dsa_switch_tree *dst = dp->ds->dst;
 	struct devlink_port_attrs attrs = {};
 	struct devlink *dl = dp->ds->devlink;
+	struct dsa_switch *ds = dp->ds;
 	const unsigned char *id;
 	unsigned char len;
 	int err;
 
+	memset(dlp, 0, sizeof(*dlp));
+	devlink_port_init(dl, dlp);
+
+	if (ds->ops->port_setup) {
+		err = ds->ops->port_setup(ds, dp->index);
+		if (err)
+			return err;
+	}
+
 	id = (const unsigned char *)&dst->index;
 	len = sizeof(dst->index);
 
 	attrs.phys.port_number = dp->index;
 	memcpy(attrs.switch_id.id, id, len);
 	attrs.switch_id.id_len = len;
-	memset(dlp, 0, sizeof(*dlp));
 
 	switch (dp->type) {
 	case DSA_PORT_TYPE_UNUSED:
@@ -578,24 +578,23 @@ static int dsa_port_devlink_setup(struct dsa_port *dp)
 
 	devlink_port_attrs_set(dlp, &attrs);
 	err = devlink_port_register(dl, dlp, dp->index);
+	if (err) {
+		if (ds->ops->port_teardown)
+			ds->ops->port_teardown(ds, dp->index);
+		return err;
+	}
+	dp->devlink_port_setup = true;
 
-	if (!err)
-		dp->devlink_port_setup = true;
-
-	return err;
+	return 0;
 }
 
 static void dsa_port_teardown(struct dsa_port *dp)
 {
 	struct devlink_port *dlp = &dp->devlink_port;
-	struct dsa_switch *ds = dp->ds;
 
 	if (!dp->setup)
 		return;
 
-	if (ds->ops->port_teardown)
-		ds->ops->port_teardown(ds, dp->index);
-
 	devlink_port_type_clear(dlp);
 
 	switch (dp->type) {
@@ -625,40 +624,25 @@ static void dsa_port_teardown(struct dsa_port *dp)
 static void dsa_port_devlink_teardown(struct dsa_port *dp)
 {
 	struct devlink_port *dlp = &dp->devlink_port;
+	struct dsa_switch *ds = dp->ds;
 
-	if (dp->devlink_port_setup)
+	if (dp->devlink_port_setup) {
 		devlink_port_unregister(dlp);
+		if (ds->ops->port_teardown)
+			ds->ops->port_teardown(ds, dp->index);
+		devlink_port_fini(dlp);
+	}
 	dp->devlink_port_setup = false;
 }
 
 /* Destroy the current devlink port, and create a new one which has the UNUSED
- * flavour. At this point, any call to ds->ops->port_setup has been already
- * balanced out by a call to ds->ops->port_teardown, so we know that any
- * devlink port regions the driver had are now unregistered. We then call its
- * ds->ops->port_setup again, in order for the driver to re-create them on the
- * new devlink port.
+ * flavour.
  */
 static int dsa_port_reinit_as_unused(struct dsa_port *dp)
 {
-	struct dsa_switch *ds = dp->ds;
-	int err;
-
 	dsa_port_devlink_teardown(dp);
 	dp->type = DSA_PORT_TYPE_UNUSED;
-	err = dsa_port_devlink_setup(dp);
-	if (err)
-		return err;
-
-	if (ds->ops->port_setup) {
-		/* On error, leave the devlink port registered,
-		 * dsa_switch_teardown will clean it up later.
-		 */
-		err = ds->ops->port_setup(ds, dp->index);
-		if (err)
-			return err;
-	}
-
-	return 0;
+	return dsa_port_devlink_setup(dp);
 }
 
 static int dsa_devlink_info_get(struct devlink *dl,
-- 
2.37.1

[patch net-next v2 5/7] net: dsa: don't leave dangling pointers in dp->pl when failing

[Jiri Pirko]

From: Vladimir Oltean <vladimir.oltean@nxp.com>

There is a desire to simplify the dsa_port registration path with
devlink, and this involves reworking a bit how user ports which fail to
connect to their PHY (because it's missing) get reinitialized as UNUSED
devlink ports.

The desire is for the change to look something like this; basically
dsa_port_setup() has failed, we just change dp->type and call
dsa_port_setup() again.

-/* Destroy the current devlink port, and create a new one which has the UNUSED
- * flavour.
- */
-static int dsa_port_reinit_as_unused(struct dsa_port *dp)
+static int dsa_port_setup_as_unused(struct dsa_port *dp)
 {
-	dsa_port_devlink_teardown(dp);
 	dp->type = DSA_PORT_TYPE_UNUSED;
-	return dsa_port_devlink_setup(dp);
+	return dsa_port_setup(dp);
 }

For an UNUSED port, dsa_port_setup() mostly only calls dsa_port_devlink_setup()
anyway, so we could get away with calling just that. But if we call the
full blown dsa_port_setup(dp) (which will be needed to properly set
dp->setup = true), the callee will have the tendency to go through this
code block too, and call dsa_port_disable(dp):

	switch (dp->type) {
	case DSA_PORT_TYPE_UNUSED:
		dsa_port_disable(dp);
		break;

That is not very good, because dsa_port_disable() has this hidden inside
of it:

	if (dp->pl)
		phylink_stop(dp->pl);

Fact is, we are not prepared to handle a call to dsa_port_disable() with
a struct dsa_port that came from a previous (and failed) call to
dsa_port_setup(). We do not clean up dp->pl, and this will make the
second call to dsa_port_setup() call phylink_stop() on a dangling dp->pl
pointer.

Solve this by creating an API for phylink destruction which is symmetric
to the phylink creation, and never leave dp->pl set to anything except
NULL or a valid phylink structure.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
---
 net/dsa/dsa_priv.h |  1 +
 net/dsa/port.c     | 22 +++++++++++++++-------
 net/dsa/slave.c    |  6 +++---
 3 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index 129e4a649c7e..6e65c7ffd6f3 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -294,6 +294,7 @@ int dsa_port_mrp_add_ring_role(const struct dsa_port *dp,
 int dsa_port_mrp_del_ring_role(const struct dsa_port *dp,
 			       const struct switchdev_obj_ring_role_mrp *mrp);
 int dsa_port_phylink_create(struct dsa_port *dp);
+void dsa_port_phylink_destroy(struct dsa_port *dp);
 int dsa_shared_port_link_register_of(struct dsa_port *dp);
 void dsa_shared_port_link_unregister_of(struct dsa_port *dp);
 int dsa_port_hsr_join(struct dsa_port *dp, struct net_device *hsr);
diff --git a/net/dsa/port.c b/net/dsa/port.c
index e6289a1db0a0..e4a0513816bb 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -1661,6 +1661,7 @@ int dsa_port_phylink_create(struct dsa_port *dp)
 {
 	struct dsa_switch *ds = dp->ds;
 	phy_interface_t mode;
+	struct phylink *pl;
 	int err;
 
 	err = of_get_phy_mode(dp->dn, &mode);
@@ -1677,16 +1678,24 @@ int dsa_port_phylink_create(struct dsa_port *dp)
 	if (ds->ops->phylink_get_caps)
 		ds->ops->phylink_get_caps(ds, dp->index, &dp->pl_config);
 
-	dp->pl = phylink_create(&dp->pl_config, of_fwnode_handle(dp->dn),
-				mode, &dsa_port_phylink_mac_ops);
-	if (IS_ERR(dp->pl)) {
+	pl = phylink_create(&dp->pl_config, of_fwnode_handle(dp->dn),
+			    mode, &dsa_port_phylink_mac_ops);
+	if (IS_ERR(pl)) {
 		pr_err("error creating PHYLINK: %ld\n", PTR_ERR(dp->pl));
-		return PTR_ERR(dp->pl);
+		return PTR_ERR(pl);
 	}
 
+	dp->pl = pl;
+
 	return 0;
 }
 
+void dsa_port_phylink_destroy(struct dsa_port *dp)
+{
+	phylink_destroy(dp->pl);
+	dp->pl = NULL;
+}
+
 static int dsa_shared_port_setup_phy_of(struct dsa_port *dp, bool enable)
 {
 	struct dsa_switch *ds = dp->ds;
@@ -1781,7 +1790,7 @@ static int dsa_shared_port_phylink_register(struct dsa_port *dp)
 	return 0;
 
 err_phy_connect:
-	phylink_destroy(dp->pl);
+	dsa_port_phylink_destroy(dp);
 	return err;
 }
 
@@ -1983,8 +1992,7 @@ void dsa_shared_port_link_unregister_of(struct dsa_port *dp)
 		rtnl_lock();
 		phylink_disconnect_phy(dp->pl);
 		rtnl_unlock();
-		phylink_destroy(dp->pl);
-		dp->pl = NULL;
+		dsa_port_phylink_destroy(dp);
 		return;
 	}
 
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index aa47ddc19fdf..1a59918d3b30 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -2304,7 +2304,7 @@ static int dsa_slave_phy_setup(struct net_device *slave_dev)
 	if (ret) {
 		netdev_err(slave_dev, "failed to connect to PHY: %pe\n",
 			   ERR_PTR(ret));
-		phylink_destroy(dp->pl);
+		dsa_port_phylink_destroy(dp);
 	}
 
 	return ret;
@@ -2476,7 +2476,7 @@ int dsa_slave_create(struct dsa_port *port)
 	rtnl_lock();
 	phylink_disconnect_phy(p->dp->pl);
 	rtnl_unlock();
-	phylink_destroy(p->dp->pl);
+	dsa_port_phylink_destroy(p->dp);
 out_gcells:
 	gro_cells_destroy(&p->gcells);
 out_free:
@@ -2499,7 +2499,7 @@ void dsa_slave_destroy(struct net_device *slave_dev)
 	phylink_disconnect_phy(dp->pl);
 	rtnl_unlock();
 
-	phylink_destroy(dp->pl);
+	dsa_port_phylink_destroy(dp);
 	gro_cells_destroy(&p->gcells);
 	free_percpu(slave_dev->tstats);
 	free_netdev(slave_dev);
-- 
2.37.1

[patch net-next v2 6/7] net: dsa: don't do devlink port setup early

[Jiri Pirko]

From: Jiri Pirko <jiri@nvidia.com>

Commit 3122433eb533 ("net: dsa: Register devlink ports before calling DSA driver setup()")
moved devlink port setup to be done early before driver setup()
was called. That is no longer needed, so move the devlink port
initialization back to dsa_port_setup(), as the first thing done there.

Note there is no longer needed to reinit port as unused if
dsa_port_setup() fails, as it unregisters the devlink port instance on
the error path.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
---
v1->v2:
- added back the reinit as unused in case port setup fails
---
 net/dsa/dsa2.c | 176 +++++++++++++++++++++++--------------------------
 1 file changed, 82 insertions(+), 94 deletions(-)

diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index 6f555b1bb483..747c0364fb0f 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -461,6 +461,74 @@ static void dsa_tree_teardown_cpu_ports(struct dsa_switch_tree *dst)
 			dp->cpu_dp = NULL;
 }
 
+static int dsa_port_devlink_setup(struct dsa_port *dp)
+{
+	struct devlink_port *dlp = &dp->devlink_port;
+	struct dsa_switch_tree *dst = dp->ds->dst;
+	struct devlink_port_attrs attrs = {};
+	struct devlink *dl = dp->ds->devlink;
+	struct dsa_switch *ds = dp->ds;
+	const unsigned char *id;
+	unsigned char len;
+	int err;
+
+	memset(dlp, 0, sizeof(*dlp));
+	devlink_port_init(dl, dlp);
+
+	if (ds->ops->port_setup) {
+		err = ds->ops->port_setup(ds, dp->index);
+		if (err)
+			return err;
+	}
+
+	id = (const unsigned char *)&dst->index;
+	len = sizeof(dst->index);
+
+	attrs.phys.port_number = dp->index;
+	memcpy(attrs.switch_id.id, id, len);
+	attrs.switch_id.id_len = len;
+
+	switch (dp->type) {
+	case DSA_PORT_TYPE_UNUSED:
+		attrs.flavour = DEVLINK_PORT_FLAVOUR_UNUSED;
+		break;
+	case DSA_PORT_TYPE_CPU:
+		attrs.flavour = DEVLINK_PORT_FLAVOUR_CPU;
+		break;
+	case DSA_PORT_TYPE_DSA:
+		attrs.flavour = DEVLINK_PORT_FLAVOUR_DSA;
+		break;
+	case DSA_PORT_TYPE_USER:
+		attrs.flavour = DEVLINK_PORT_FLAVOUR_PHYSICAL;
+		break;
+	}
+
+	devlink_port_attrs_set(dlp, &attrs);
+	err = devlink_port_register(dl, dlp, dp->index);
+	if (err) {
+		if (ds->ops->port_teardown)
+			ds->ops->port_teardown(ds, dp->index);
+		return err;
+	}
+	dp->devlink_port_setup = true;
+
+	return 0;
+}
+
+static void dsa_port_devlink_teardown(struct dsa_port *dp)
+{
+	struct devlink_port *dlp = &dp->devlink_port;
+	struct dsa_switch *ds = dp->ds;
+
+	if (dp->devlink_port_setup) {
+		devlink_port_unregister(dlp);
+		if (ds->ops->port_teardown)
+			ds->ops->port_teardown(ds, dp->index);
+		devlink_port_fini(dlp);
+	}
+	dp->devlink_port_setup = false;
+}
+
 static int dsa_port_setup(struct dsa_port *dp)
 {
 	struct devlink_port *dlp = &dp->devlink_port;
@@ -472,6 +540,10 @@ static int dsa_port_setup(struct dsa_port *dp)
 	if (dp->setup)
 		return 0;
 
+	err = dsa_port_devlink_setup(dp);
+	if (err)
+		return err;
+
 	switch (dp->type) {
 	case DSA_PORT_TYPE_UNUSED:
 		dsa_port_disable(dp);
@@ -526,64 +598,12 @@ static int dsa_port_setup(struct dsa_port *dp)
 		dsa_port_disable(dp);
 	if (err && dsa_port_link_registered)
 		dsa_shared_port_link_unregister_of(dp);
-	if (err)
-		return err;
-
-	dp->setup = true;
-
-	return 0;
-}
-
-static int dsa_port_devlink_setup(struct dsa_port *dp)
-{
-	struct devlink_port *dlp = &dp->devlink_port;
-	struct dsa_switch_tree *dst = dp->ds->dst;
-	struct devlink_port_attrs attrs = {};
-	struct devlink *dl = dp->ds->devlink;
-	struct dsa_switch *ds = dp->ds;
-	const unsigned char *id;
-	unsigned char len;
-	int err;
-
-	memset(dlp, 0, sizeof(*dlp));
-	devlink_port_init(dl, dlp);
-
-	if (ds->ops->port_setup) {
-		err = ds->ops->port_setup(ds, dp->index);
-		if (err)
-			return err;
-	}
-
-	id = (const unsigned char *)&dst->index;
-	len = sizeof(dst->index);
-
-	attrs.phys.port_number = dp->index;
-	memcpy(attrs.switch_id.id, id, len);
-	attrs.switch_id.id_len = len;
-
-	switch (dp->type) {
-	case DSA_PORT_TYPE_UNUSED:
-		attrs.flavour = DEVLINK_PORT_FLAVOUR_UNUSED;
-		break;
-	case DSA_PORT_TYPE_CPU:
-		attrs.flavour = DEVLINK_PORT_FLAVOUR_CPU;
-		break;
-	case DSA_PORT_TYPE_DSA:
-		attrs.flavour = DEVLINK_PORT_FLAVOUR_DSA;
-		break;
-	case DSA_PORT_TYPE_USER:
-		attrs.flavour = DEVLINK_PORT_FLAVOUR_PHYSICAL;
-		break;
-	}
-
-	devlink_port_attrs_set(dlp, &attrs);
-	err = devlink_port_register(dl, dlp, dp->index);
 	if (err) {
-		if (ds->ops->port_teardown)
-			ds->ops->port_teardown(ds, dp->index);
+		dsa_port_devlink_teardown(dp);
 		return err;
 	}
-	dp->devlink_port_setup = true;
+
+	dp->setup = true;
 
 	return 0;
 }
@@ -618,31 +638,15 @@ static void dsa_port_teardown(struct dsa_port *dp)
 		break;
 	}
 
-	dp->setup = false;
-}
-
-static void dsa_port_devlink_teardown(struct dsa_port *dp)
-{
-	struct devlink_port *dlp = &dp->devlink_port;
-	struct dsa_switch *ds = dp->ds;
+	dsa_port_devlink_teardown(dp);
 
-	if (dp->devlink_port_setup) {
-		devlink_port_unregister(dlp);
-		if (ds->ops->port_teardown)
-			ds->ops->port_teardown(ds, dp->index);
-		devlink_port_fini(dlp);
-	}
-	dp->devlink_port_setup = false;
+	dp->setup = false;
 }
 
-/* Destroy the current devlink port, and create a new one which has the UNUSED
- * flavour.
- */
-static int dsa_port_reinit_as_unused(struct dsa_port *dp)
+static int dsa_port_setup_as_unused(struct dsa_port *dp)
 {
-	dsa_port_devlink_teardown(dp);
 	dp->type = DSA_PORT_TYPE_UNUSED;
-	return dsa_port_devlink_setup(dp);
+	return dsa_port_setup(dp);
 }
 
 static int dsa_devlink_info_get(struct devlink *dl,
@@ -866,7 +870,6 @@ static int dsa_switch_setup(struct dsa_switch *ds)
 {
 	struct dsa_devlink_priv *dl_priv;
 	struct device_node *dn;
-	struct dsa_port *dp;
 	int err;
 
 	if (ds->setup)
@@ -889,18 +892,9 @@ static int dsa_switch_setup(struct dsa_switch *ds)
 	dl_priv = devlink_priv(ds->devlink);
 	dl_priv->ds = ds;
 
-	/* Setup devlink port instances now, so that the switch
-	 * setup() can register regions etc, against the ports
-	 */
-	dsa_switch_for_each_port(dp, ds) {
-		err = dsa_port_devlink_setup(dp);
-		if (err)
-			goto unregister_devlink_ports;
-	}
-
 	err = dsa_switch_register_notifier(ds);
 	if (err)
-		goto unregister_devlink_ports;
+		goto devlink_free;
 
 	ds->configure_vlan_while_not_filtering = true;
 
@@ -941,9 +935,7 @@ static int dsa_switch_setup(struct dsa_switch *ds)
 		ds->ops->teardown(ds);
 unregister_notifier:
 	dsa_switch_unregister_notifier(ds);
-unregister_devlink_ports:
-	dsa_switch_for_each_port(dp, ds)
-		dsa_port_devlink_teardown(dp);
+devlink_free:
 	devlink_free(ds->devlink);
 	ds->devlink = NULL;
 	return err;
@@ -951,8 +943,6 @@ static int dsa_switch_setup(struct dsa_switch *ds)
 
 static void dsa_switch_teardown(struct dsa_switch *ds)
 {
-	struct dsa_port *dp;
-
 	if (!ds->setup)
 		return;
 
@@ -971,8 +961,6 @@ static void dsa_switch_teardown(struct dsa_switch *ds)
 	dsa_switch_unregister_notifier(ds);
 
 	if (ds->devlink) {
-		dsa_switch_for_each_port(dp, ds)
-			dsa_port_devlink_teardown(dp);
 		devlink_free(ds->devlink);
 		ds->devlink = NULL;
 	}
@@ -1025,7 +1013,7 @@ static int dsa_tree_setup_ports(struct dsa_switch_tree *dst)
 		if (dsa_port_is_user(dp) || dsa_port_is_unused(dp)) {
 			err = dsa_port_setup(dp);
 			if (err) {
-				err = dsa_port_reinit_as_unused(dp);
+				err = dsa_port_setup_as_unused(dp);
 				if (err)
 					goto teardown;
 			}
-- 
2.37.1

[patch net-next v2 7/7] net: dsa: remove bool devlink_port_setup

[Jiri Pirko]

From: Vladimir Oltean <vladimir.oltean@nxp.com>

Since dsa_port_devlink_setup() and dsa_port_devlink_teardown() are
already called from code paths which only execute once per port (due to
the existing bool dp->setup), keeping another dp->devlink_port_setup is
redundant, because we can already manage to balance the calls properly
(and not call teardown when setup was never called, or call setup twice,
or things like that).

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
---
 include/net/dsa.h |  2 --
 net/dsa/dsa2.c    | 14 ++++++--------
 2 files changed, 6 insertions(+), 10 deletions(-)

diff --git a/include/net/dsa.h b/include/net/dsa.h
index d777eac5694f..ee369670e20e 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -294,8 +294,6 @@ struct dsa_port {
 
 	u8			lag_tx_enabled:1;
 
-	u8			devlink_port_setup:1;
-
 	/* Master state bits, valid only on CPU ports */
 	u8			master_admin_up:1;
 	u8			master_oper_up:1;
diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index 747c0364fb0f..af0e2c0394ac 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -510,7 +510,6 @@ static int dsa_port_devlink_setup(struct dsa_port *dp)
 			ds->ops->port_teardown(ds, dp->index);
 		return err;
 	}
-	dp->devlink_port_setup = true;
 
 	return 0;
 }
@@ -520,13 +519,12 @@ static void dsa_port_devlink_teardown(struct dsa_port *dp)
 	struct devlink_port *dlp = &dp->devlink_port;
 	struct dsa_switch *ds = dp->ds;
 
-	if (dp->devlink_port_setup) {
-		devlink_port_unregister(dlp);
-		if (ds->ops->port_teardown)
-			ds->ops->port_teardown(ds, dp->index);
-		devlink_port_fini(dlp);
-	}
-	dp->devlink_port_setup = false;
+	devlink_port_unregister(dlp);
+
+	if (ds->ops->port_teardown)
+		ds->ops->port_teardown(ds, dp->index);
+
+	devlink_port_fini(dlp);
 }
 
 static int dsa_port_setup(struct dsa_port *dp)
-- 
2.37.1