diff mbox series

[net-next,2/2] devlink: Allocate devlink directly in requested net namespace

Message ID ca29973a59c9c128ab960e3cbff8dfa95280b6b0.1627545799.git.leonro@nvidia.com
State New
Headers show
Series None | expand

Commit Message

Leon Romanovsky July 29, 2021, 8:15 a.m. UTC 
From: Leon Romanovsky <leonro@nvidia.com>

There is no need in extra call indirection and check from impossible
flow where someone tries to set namespace without prior call
to devlink_alloc().

Instead of this extra logic and additional EXPORT_SYMBOL, use specialized
devlink allocation function that receives net namespace as an argument.

Such specialized API allows clear view when devlink initialized in wrong
net namespace and/or kernel users don't try to change devlink namespace
under the hood.

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
---
 drivers/net/netdevsim/dev.c |  4 ++--
 include/net/devlink.h       | 14 ++++++++++++--
 net/core/devlink.c          | 26 ++++++++------------------
 3 files changed, 22 insertions(+), 22 deletions(-)

Comments

Jiri Pirko July 29, 2021, 11:55 a.m. UTC | #1 
Thu, Jul 29, 2021 at 10:15:26AM CEST, leon@kernel.org wrote:
>From: Leon Romanovsky <leonro@nvidia.com>
>
>There is no need in extra call indirection and check from impossible
>flow where someone tries to set namespace without prior call
>to devlink_alloc().
>
>Instead of this extra logic and additional EXPORT_SYMBOL, use specialized
>devlink allocation function that receives net namespace as an argument.
>
>Such specialized API allows clear view when devlink initialized in wrong
>net namespace and/or kernel users don't try to change devlink namespace
>under the hood.
>
>Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
>---
> drivers/net/netdevsim/dev.c |  4 ++--
> include/net/devlink.h       | 14 ++++++++++++--
> net/core/devlink.c          | 26 ++++++++------------------
> 3 files changed, 22 insertions(+), 22 deletions(-)
>
>diff --git a/drivers/net/netdevsim/dev.c b/drivers/net/netdevsim/dev.c
>index 6348307bfa84..d538a39d4225 100644
>--- a/drivers/net/netdevsim/dev.c
>+++ b/drivers/net/netdevsim/dev.c
>@@ -1431,10 +1431,10 @@ int nsim_dev_probe(struct nsim_bus_dev *nsim_bus_dev)
> 	struct devlink *devlink;
> 	int err;
> 
>-	devlink = devlink_alloc(&nsim_dev_devlink_ops, sizeof(*nsim_dev));
>+	devlink = devlink_alloc_ns(&nsim_dev_devlink_ops, sizeof(*nsim_dev),
>+				   nsim_bus_dev->initial_net);
> 	if (!devlink)
> 		return -ENOMEM;
>-	devlink_net_set(devlink, nsim_bus_dev->initial_net);
> 	nsim_dev = devlink_priv(devlink);
> 	nsim_dev->nsim_bus_dev = nsim_bus_dev;
> 	nsim_dev->switch_id.id_len = sizeof(nsim_dev->switch_id.id);
>diff --git a/include/net/devlink.h b/include/net/devlink.h
>index e48a62320407..b4691c40320f 100644
>--- a/include/net/devlink.h
>+++ b/include/net/devlink.h
>@@ -1540,8 +1540,18 @@ static inline struct devlink *netdev_to_devlink(struct net_device *dev)
> struct ib_device;
> 
> struct net *devlink_net(const struct devlink *devlink);
>-void devlink_net_set(struct devlink *devlink, struct net *net);
>-struct devlink *devlink_alloc(const struct devlink_ops *ops, size_t priv_size);
>+/* This RAW call is intended for software devices that can

Not sure what "RAW call" is, perhaps you can just avoid this here.

Otherwise, this patch looks fine to me:
Reviewed-by: Jiri Pirko <jiri@nvidia.com>

[...]
Leon Romanovsky July 29, 2021, 12:06 p.m. UTC | #2 
On Thu, Jul 29, 2021 at 01:55:29PM +0200, Jiri Pirko wrote:
> Thu, Jul 29, 2021 at 10:15:26AM CEST, leon@kernel.org wrote:
> >From: Leon Romanovsky <leonro@nvidia.com>
> >
> >There is no need in extra call indirection and check from impossible
> >flow where someone tries to set namespace without prior call
> >to devlink_alloc().
> >
> >Instead of this extra logic and additional EXPORT_SYMBOL, use specialized
> >devlink allocation function that receives net namespace as an argument.
> >
> >Such specialized API allows clear view when devlink initialized in wrong
> >net namespace and/or kernel users don't try to change devlink namespace
> >under the hood.
> >
> >Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
> >---
> > drivers/net/netdevsim/dev.c |  4 ++--
> > include/net/devlink.h       | 14 ++++++++++++--
> > net/core/devlink.c          | 26 ++++++++------------------
> > 3 files changed, 22 insertions(+), 22 deletions(-)
> >
> >diff --git a/drivers/net/netdevsim/dev.c b/drivers/net/netdevsim/dev.c
> >index 6348307bfa84..d538a39d4225 100644
> >--- a/drivers/net/netdevsim/dev.c
> >+++ b/drivers/net/netdevsim/dev.c
> >@@ -1431,10 +1431,10 @@ int nsim_dev_probe(struct nsim_bus_dev *nsim_bus_dev)
> > 	struct devlink *devlink;
> > 	int err;
> > 
> >-	devlink = devlink_alloc(&nsim_dev_devlink_ops, sizeof(*nsim_dev));
> >+	devlink = devlink_alloc_ns(&nsim_dev_devlink_ops, sizeof(*nsim_dev),
> >+				   nsim_bus_dev->initial_net);
> > 	if (!devlink)
> > 		return -ENOMEM;
> >-	devlink_net_set(devlink, nsim_bus_dev->initial_net);
> > 	nsim_dev = devlink_priv(devlink);
> > 	nsim_dev->nsim_bus_dev = nsim_bus_dev;
> > 	nsim_dev->switch_id.id_len = sizeof(nsim_dev->switch_id.id);
> >diff --git a/include/net/devlink.h b/include/net/devlink.h
> >index e48a62320407..b4691c40320f 100644
> >--- a/include/net/devlink.h
> >+++ b/include/net/devlink.h
> >@@ -1540,8 +1540,18 @@ static inline struct devlink *netdev_to_devlink(struct net_device *dev)
> > struct ib_device;
> > 
> > struct net *devlink_net(const struct devlink *devlink);
> >-void devlink_net_set(struct devlink *devlink, struct net *net);
> >-struct devlink *devlink_alloc(const struct devlink_ops *ops, size_t priv_size);
> >+/* This RAW call is intended for software devices that can
> 
> Not sure what "RAW call" is, perhaps you can just avoid this here.

I wanted to emphasize the message that we shouldn't see this call in
regular drivers and it is very specific to SW drivers.

I'll drop "RAW".

> 
> Otherwise, this patch looks fine to me:
> Reviewed-by: Jiri Pirko <jiri@nvidia.com>

Thanks

> 
> [...]
diff mbox series

Patch

diff --git a/drivers/net/netdevsim/dev.c b/drivers/net/netdevsim/dev.c
index 6348307bfa84..d538a39d4225 100644
--- a/drivers/net/netdevsim/dev.c
+++ b/drivers/net/netdevsim/dev.c
@@ -1431,10 +1431,10 @@  int nsim_dev_probe(struct nsim_bus_dev *nsim_bus_dev)
 	struct devlink *devlink;
 	int err;
 
-	devlink = devlink_alloc(&nsim_dev_devlink_ops, sizeof(*nsim_dev));
+	devlink = devlink_alloc_ns(&nsim_dev_devlink_ops, sizeof(*nsim_dev),
+				   nsim_bus_dev->initial_net);
 	if (!devlink)
 		return -ENOMEM;
-	devlink_net_set(devlink, nsim_bus_dev->initial_net);
 	nsim_dev = devlink_priv(devlink);
 	nsim_dev->nsim_bus_dev = nsim_bus_dev;
 	nsim_dev->switch_id.id_len = sizeof(nsim_dev->switch_id.id);
diff --git a/include/net/devlink.h b/include/net/devlink.h
index e48a62320407..b4691c40320f 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -1540,8 +1540,18 @@  static inline struct devlink *netdev_to_devlink(struct net_device *dev)
 struct ib_device;
 
 struct net *devlink_net(const struct devlink *devlink);
-void devlink_net_set(struct devlink *devlink, struct net *net);
-struct devlink *devlink_alloc(const struct devlink_ops *ops, size_t priv_size);
+/* This RAW call is intended for software devices that can
+ * create devlink instance in other namespaces than init_net.
+ *
+ * Drivers that operate on real HW must use devlink_alloc() instead.
+ */
+struct devlink *devlink_alloc_ns(const struct devlink_ops *ops,
+				 size_t priv_size, struct net *net);
+static inline struct devlink *devlink_alloc(const struct devlink_ops *ops,
+					    size_t priv_size)
+{
+	return devlink_alloc_ns(ops, priv_size, &init_net);
+}
 int devlink_register(struct devlink *devlink, struct device *dev);
 void devlink_unregister(struct devlink *devlink);
 void devlink_reload_enable(struct devlink *devlink);
diff --git a/net/core/devlink.c b/net/core/devlink.c
index 54e2a0375539..b419b7a6ec40 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -108,19 +108,6 @@  struct net *devlink_net(const struct devlink *devlink)
 }
 EXPORT_SYMBOL_GPL(devlink_net);
 
-static void __devlink_net_set(struct devlink *devlink, struct net *net)
-{
-	write_pnet(&devlink->_net, net);
-}
-
-void devlink_net_set(struct devlink *devlink, struct net *net)
-{
-	if (WARN_ON(devlink->dev))
-		return;
-	__devlink_net_set(devlink, net);
-}
-EXPORT_SYMBOL_GPL(devlink_net_set);
-
 static struct devlink *devlink_get_from_attrs(struct net *net,
 					      struct nlattr **attrs)
 {
@@ -3920,7 +3907,7 @@  static int devlink_reload(struct devlink *devlink, struct net *dest_net,
 		return err;
 
 	if (dest_net && !net_eq(dest_net, curr_net))
-		__devlink_net_set(devlink, dest_net);
+		write_pnet(&devlink->_net, dest_net);
 
 	err = devlink->ops->reload_up(devlink, action, limit, actions_performed, extack);
 	devlink_reload_failed_set(devlink, !!err);
@@ -8776,15 +8763,18 @@  static bool devlink_reload_actions_valid(const struct devlink_ops *ops)
 }
 
 /**
- *	devlink_alloc - Allocate new devlink instance resources
+ *	devlink_alloc_ns - Allocate new devlink instance resources
+ *	in specific namespace
  *
  *	@ops: ops
  *	@priv_size: size of user private data
+ *	@net: net namespace
  *
  *	Allocate new devlink instance resources, including devlink index
  *	and name.
  */
-struct devlink *devlink_alloc(const struct devlink_ops *ops, size_t priv_size)
+struct devlink *devlink_alloc_ns(const struct devlink_ops *ops,
+				 size_t priv_size, struct net *net)
 {
 	struct devlink *devlink;
 
@@ -8799,7 +8789,7 @@  struct devlink *devlink_alloc(const struct devlink_ops *ops, size_t priv_size)
 		return NULL;
 	devlink->ops = ops;
 	xa_init_flags(&devlink->snapshot_ids, XA_FLAGS_ALLOC);
-	__devlink_net_set(devlink, &init_net);
+	write_pnet(&devlink->_net, net);
 	INIT_LIST_HEAD(&devlink->port_list);
 	INIT_LIST_HEAD(&devlink->rate_list);
 	INIT_LIST_HEAD(&devlink->sb_list);
@@ -8815,7 +8805,7 @@  struct devlink *devlink_alloc(const struct devlink_ops *ops, size_t priv_size)
 	mutex_init(&devlink->reporters_lock);
 	return devlink;
 }
-EXPORT_SYMBOL_GPL(devlink_alloc);
+EXPORT_SYMBOL_GPL(devlink_alloc_ns);
 
 /**
  *	devlink_register - Register devlink instance