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>
This commit is contained in:
Avihai Horon 2020-09-23 19:50:14 +03:00 committed by Jason Gunthorpe
parent 1c15b4f2a4
commit c4b4d548fa
3 changed files with 74 additions and 3 deletions

View File

@ -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);

View File

@ -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 */

View File

@ -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