Commit c4b4d548 authored by Avihai Horon's avatar Avihai Horon Committed by Jason Gunthorpe
Browse files

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: default avatarAvihai Horon <avihaih@nvidia.com>
Signed-off-by: default avatarLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 1c15b4f2

drivers/infiniband/core/cache.c

+63 −3
Original line number Diff line number Diff line
@@ -1247,6 +1247,67 @@ done: 
}

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
@@ -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);

include/rdma/ib_cache.h

+3 −0
Original line number Diff line number Diff line
@@ -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 */

include/uapi/rdma/ib_user_ioctl_verbs.h

+8 −0
Original line number Diff line number Diff line
@@ -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

CRA Git | Maintained and supported by SUSTech CRA and CCSE