diff options
| -rw-r--r-- | drivers/infiniband/core/core_priv.h | 1 | ||||
| -rw-r--r-- | drivers/infiniband/core/device.c | 13 | ||||
| -rw-r--r-- | include/rdma/ib_verbs.h | 24 |
3 files changed, 32 insertions, 6 deletions
diff --git a/drivers/infiniband/core/core_priv.h b/drivers/infiniband/core/core_priv.h index 3cd830d52967..616734313f0c 100644 --- a/drivers/infiniband/core/core_priv.h +++ b/drivers/infiniband/core/core_priv.h @@ -267,7 +267,6 @@ static inline int ib_mad_enforce_security(struct ib_mad_agent_private *map, #endif struct ib_device *ib_device_get_by_index(u32 ifindex); -void ib_device_put(struct ib_device *device); /* RDMA device netlink */ void nldev_init(void); void nldev_exit(void); diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c index 8872453e26c0..238ec42778ef 100644 --- a/drivers/infiniband/core/device.c +++ b/drivers/infiniband/core/device.c @@ -156,19 +156,26 @@ struct ib_device *ib_device_get_by_index(u32 index) down_read(&lists_rwsem); device = __ib_device_get_by_index(index); if (device) { - /* Do not return a device if unregistration has started. */ - if (!refcount_inc_not_zero(&device->refcount)) + if (!ib_device_try_get(device)) device = NULL; } up_read(&lists_rwsem); return device; } +/** + * ib_device_put - Release IB device reference + * @device: device whose reference to be released + * + * ib_device_put() releases reference to the IB device to allow it to be + * unregistered and eventually free. + */ void ib_device_put(struct ib_device *device) { if (refcount_dec_and_test(&device->refcount)) complete(&device->unreg_completion); } +EXPORT_SYMBOL(ib_device_put); static struct ib_device *__ib_device_get_by_name(const char *name) { @@ -303,7 +310,6 @@ struct ib_device *ib_alloc_device(size_t size) rwlock_init(&device->client_data_lock); INIT_LIST_HEAD(&device->client_data_list); INIT_LIST_HEAD(&device->port_list); - refcount_set(&device->refcount, 1); init_completion(&device->unreg_completion); return device; @@ -620,6 +626,7 @@ int ib_register_device(struct ib_device *device, const char *name, goto cg_cleanup; } + refcount_set(&device->refcount, 1); device->reg_state = IB_DEV_REGISTERED; list_for_each_entry(client, &client_list, list) diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h index a3ceed3a040a..80debf5982ac 100644 --- a/include/rdma/ib_verbs.h +++ b/include/rdma/ib_verbs.h @@ -2579,9 +2579,10 @@ struct ib_device { const struct uapi_definition *driver_def; enum rdma_driver_id driver_id; + /* - * Provides synchronization between device unregistration and netlink - * commands on a device. To be used only by core. + * Positive refcount indicates that the device is currently + * registered and cannot be unregistered. */ refcount_t refcount; struct completion unreg_completion; @@ -3926,6 +3927,25 @@ static inline bool ib_access_writable(int access_flags) int ib_check_mr_status(struct ib_mr *mr, u32 check_mask, struct ib_mr_status *mr_status); +/** + * ib_device_try_get: Hold a registration lock + * device: The device to lock + * + * A device under an active registration lock cannot become unregistered. It + * is only possible to obtain a registration lock on a device that is fully + * registered, otherwise this function returns false. + * + * The registration lock is only necessary for actions which require the + * device to still be registered. Uses that only require the device pointer to + * be valid should use get_device(&ibdev->dev) to hold the memory. + * + */ +static inline bool ib_device_try_get(struct ib_device *dev) +{ + return refcount_inc_not_zero(&dev->refcount); +} + +void ib_device_put(struct ib_device *device); struct net_device *ib_get_net_dev_by_params(struct ib_device *dev, u8 port, u16 pkey, const union ib_gid *gid, const struct sockaddr *addr); |