diff options
| author | Jakub Kicinski <kuba@kernel.org> | 2021-10-30 19:18:50 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-11-01 14:26:07 +0100 |
| commit | 46db1b77cd4f082c4e908c8f8086a2f7aae28b62 (patch) | |
| tree | 7d43077c2639337ffdd30b8430dcdc13e51ac3b2 | |
| parent | ethtool: handle info/flash data copying outside rtnl_lock (diff) | |
| download | linux-46db1b77cd4f082c4e908c8f8086a2f7aae28b62.tar.xz linux-46db1b77cd4f082c4e908c8f8086a2f7aae28b62.zip | |
devlink: expose get/put functions
Allow those who hold implicit reference on a devlink instance
to try to take a full ref on it. This will be used from netdev
code which has an implicit ref because of driver call ordering.
Note that after recent changes devlink_unregister() may happen
before netdev unregister, but devlink_free() should still happen
after, so we are safe to try, but we can't just refcount_inc()
and assume it's not zero.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/net/devlink.h | 12 | ||||
| -rw-r--r-- | net/core/devlink.c | 8 |
2 files changed, 17 insertions, 3 deletions
diff --git a/include/net/devlink.h b/include/net/devlink.h index 1b1317d378de..991ce48f77ca 100644 --- a/include/net/devlink.h +++ b/include/net/devlink.h @@ -1726,6 +1726,9 @@ devlink_trap_policers_unregister(struct devlink *devlink, #if IS_ENABLED(CONFIG_NET_DEVLINK) +struct devlink *__must_check devlink_try_get(struct devlink *devlink); +void devlink_put(struct devlink *devlink); + void devlink_compat_running_version(struct net_device *dev, char *buf, size_t len); int devlink_compat_flash_update(struct net_device *dev, const char *file_name); @@ -1736,6 +1739,15 @@ int devlink_compat_switch_id_get(struct net_device *dev, #else +static inline struct devlink *devlink_try_get(struct devlink *devlink) +{ + return NULL; +} + +static inline void devlink_put(struct devlink *devlink) +{ +} + static inline void devlink_compat_running_version(struct net_device *dev, char *buf, size_t len) { diff --git a/net/core/devlink.c b/net/core/devlink.c index 2d8abe88c673..100d87fd3f65 100644 --- a/net/core/devlink.c +++ b/net/core/devlink.c @@ -182,15 +182,17 @@ struct net *devlink_net(const struct devlink *devlink) } EXPORT_SYMBOL_GPL(devlink_net); -static void devlink_put(struct devlink *devlink) +void devlink_put(struct devlink *devlink) { if (refcount_dec_and_test(&devlink->refcount)) complete(&devlink->comp); } -static bool __must_check devlink_try_get(struct devlink *devlink) +struct devlink *__must_check devlink_try_get(struct devlink *devlink) { - return refcount_inc_not_zero(&devlink->refcount); + if (refcount_inc_not_zero(&devlink->refcount)) + return devlink; + return NULL; } static struct devlink *devlink_get_from_attrs(struct net *net, |