RDMA/core: Introduce new GID table query API
Introduce rdma_query_gid_table which enables querying all the GID tables
of a given device and copying the attributes of all valid GID entries to a
provided buffer.
This API provides a faster way to query a GID table using single call and
will be used in libibverbs to improve current approach that requires
multiple calls to open, close and read multiple sysfs files for a single
GID table entry.
Link: https://lore.kernel.org/r/20200923165015.2491894-4-leon@kernel.org
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
diff --git a/drivers/infiniband/core/cache.c b/drivers/infiniband/core/cache.c
index cf49ac0..3a86a10 100644
--- a/drivers/infiniband/core/cache.c
+++ b/drivers/infiniband/core/cache.c
@@ -1248,6 +1248,67 @@ rdma_get_gid_attr(struct ib_device *device, u8 port_num, int index)
EXPORT_SYMBOL(rdma_get_gid_attr);
/**
+ * rdma_query_gid_table - Reads GID table entries of all the ports of a device up to max_entries.
+ * @device: The device to query.
+ * @entries: Entries where GID entries are returned.
+ * @max_entries: Maximum number of entries that can be returned.
+ * Entries array must be allocated to hold max_entries number of entries.
+ * @num_entries: Updated to the number of entries that were successfully read.
+ *
+ * Returns number of entries on success or appropriate error code.
+ */
+ssize_t rdma_query_gid_table(struct ib_device *device,
+ struct ib_uverbs_gid_entry *entries,
+ size_t max_entries)
+{
+ const struct ib_gid_attr *gid_attr;
+ ssize_t num_entries = 0, ret;
+ struct ib_gid_table *table;
+ unsigned int port_num, i;
+ struct net_device *ndev;
+ unsigned long flags;
+
+ rdma_for_each_port(device, port_num) {
+ if (!rdma_ib_or_roce(device, port_num))
+ continue;
+
+ table = rdma_gid_table(device, port_num);
+ read_lock_irqsave(&table->rwlock, flags);
+ for (i = 0; i < table->sz; i++) {
+ if (!is_gid_entry_valid(table->data_vec[i]))
+ continue;
+ if (num_entries >= max_entries) {
+ ret = -EINVAL;
+ goto err;
+ }
+
+ gid_attr = &table->data_vec[i]->attr;
+
+ memcpy(&entries->gid, &gid_attr->gid,
+ sizeof(gid_attr->gid));
+ entries->gid_index = gid_attr->index;
+ entries->port_num = gid_attr->port_num;
+ entries->gid_type = gid_attr->gid_type;
+ ndev = rcu_dereference_protected(
+ gid_attr->ndev,
+ lockdep_is_held(&table->rwlock));
+ if (ndev)
+ entries->netdev_ifindex = ndev->ifindex;
+
+ num_entries++;
+ entries++;
+ }
+ read_unlock_irqrestore(&table->rwlock, flags);
+ }
+
+ return num_entries;
+err:
+ read_unlock_irqrestore(&table->rwlock, flags);
+ return ret;
+}
+EXPORT_SYMBOL(rdma_query_gid_table);
+
+/**
* rdma_put_gid_attr - Release reference to the GID attribute
* @attr: Pointer to the GID attribute whose reference
* needs to be released.
@@ -1303,7 +1364,7 @@ struct net_device *rdma_read_gid_attr_ndev_rcu(const struct ib_gid_attr *attr)
struct ib_gid_table_entry *entry =
container_of(attr, struct ib_gid_table_entry, attr);
struct ib_device *device = entry->attr.device;
- struct net_device *ndev = ERR_PTR(-ENODEV);
+ struct net_device *ndev = ERR_PTR(-EINVAL);
u8 port_num = entry->attr.port_num;
struct ib_gid_table *table;
unsigned long flags;
@@ -1315,8 +1376,7 @@ struct net_device *rdma_read_gid_attr_ndev_rcu(const struct ib_gid_attr *attr)
valid = is_gid_entry_valid(table->data_vec[attr->index]);
if (valid) {
ndev = rcu_dereference(attr->ndev);
- if (!ndev ||
- (ndev && ((READ_ONCE(ndev->flags) & IFF_UP) == 0)))
+ if (!ndev)
ndev = ERR_PTR(-ENODEV);
}
read_unlock_irqrestore(&table->rwlock, flags);
diff --git a/include/rdma/ib_cache.h b/include/rdma/ib_cache.h
index 66a8f36..bae29f5 100644
--- a/include/rdma/ib_cache.h
+++ b/include/rdma/ib_cache.h
@@ -110,5 +110,8 @@ const struct ib_gid_attr *rdma_get_gid_attr(struct ib_device *device,
u8 port_num, int index);
void rdma_put_gid_attr(const struct ib_gid_attr *attr);
void rdma_hold_gid_attr(const struct ib_gid_attr *attr);
+ssize_t rdma_query_gid_table(struct ib_device *device,
+ struct ib_uverbs_gid_entry *entries,
+ size_t max_entries);
#endif /* _IB_CACHE_H */
diff --git a/include/uapi/rdma/ib_user_ioctl_verbs.h b/include/uapi/rdma/ib_user_ioctl_verbs.h
index fb8cdb3..1482008 100644
--- a/include/uapi/rdma/ib_user_ioctl_verbs.h
+++ b/include/uapi/rdma/ib_user_ioctl_verbs.h
@@ -251,4 +251,12 @@ enum rdma_driver_id {
RDMA_DRIVER_SIW,
};
+struct ib_uverbs_gid_entry {
+ __aligned_u64 gid[2];
+ __u32 gid_index;
+ __u32 port_num;
+ __u32 gid_type;
+ __u32 netdev_ifindex; /* It is 0 if there is no netdev associated with it */
+};
+
#endif