IB/core: Introduce GID attribute get, put and hold APIs

This patch introduces three APIs, rdma_get_gid_attr(),
rdma_put_gid_attr(), and rdma_hold_gid_attr() which expose the reference
counting for GID table entries to the entire stack. The kref counting is
based on the struct ib_gid_attr pointer

Later patches will convert more cache query function to return struct
ib_gid_attrs.

Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This commit is contained in:
Parav Pandit 2018-06-05 08:40:17 +03:00 committed by Jason Gunthorpe
parent f4df9a7c34
commit bf399c2cad
2 changed files with 90 additions and 0 deletions

View File

@ -286,6 +286,11 @@ static void store_gid_entry(struct ib_gid_table *table,
write_unlock_irq(&table->rwlock); write_unlock_irq(&table->rwlock);
} }
static void get_gid_entry(struct ib_gid_table_entry *entry)
{
kref_get(&entry->kref);
}
static void put_gid_entry(struct ib_gid_table_entry *entry) static void put_gid_entry(struct ib_gid_table_entry *entry)
{ {
kref_put(&entry->kref, schedule_free_gid); kref_put(&entry->kref, schedule_free_gid);
@ -1208,6 +1213,87 @@ int ib_get_cached_port_state(struct ib_device *device,
} }
EXPORT_SYMBOL(ib_get_cached_port_state); EXPORT_SYMBOL(ib_get_cached_port_state);
/**
* rdma_get_gid_attr - Returns GID attributes for a port of a device
* at a requested gid_index, if a valid GID entry exists.
* @device: The device to query.
* @port_num: The port number on the device where the GID value
* is to be queried.
* @index: Index of the GID table entry whose attributes are to
* be queried.
*
* rdma_get_gid_attr() acquires reference count of gid attributes from the
* cached GID table. Caller must invoke rdma_put_gid_attr() to release
* reference to gid attribute regardless of link layer.
*
* Returns pointer to valid gid attribute or ERR_PTR for the appropriate error
* code.
*/
const struct ib_gid_attr *
rdma_get_gid_attr(struct ib_device *device, u8 port_num, int index)
{
const struct ib_gid_attr *attr = ERR_PTR(-EINVAL);
struct ib_gid_table *table;
unsigned long flags;
if (!rdma_is_port_valid(device, port_num))
return ERR_PTR(-EINVAL);
table = rdma_gid_table(device, port_num);
if (index < 0 || index >= table->sz)
return ERR_PTR(-EINVAL);
read_lock_irqsave(&table->rwlock, flags);
if (!is_gid_entry_valid(table->data_vec[index]))
goto done;
get_gid_entry(table->data_vec[index]);
attr = &table->data_vec[index]->attr;
done:
read_unlock_irqrestore(&table->rwlock, flags);
return attr;
}
EXPORT_SYMBOL(rdma_get_gid_attr);
/**
* rdma_put_gid_attr - Release reference to the GID attribute
* @attr: Pointer to the GID attribute whose reference
* needs to be released.
*
* rdma_put_gid_attr() must be used to release reference whose
* reference is acquired using rdma_get_gid_attr() or any APIs
* which returns a pointer to the ib_gid_attr regardless of link layer
* of IB or RoCE.
*
*/
void rdma_put_gid_attr(const struct ib_gid_attr *attr)
{
struct ib_gid_table_entry *entry =
container_of(attr, struct ib_gid_table_entry, attr);
put_gid_entry(entry);
}
EXPORT_SYMBOL(rdma_put_gid_attr);
/**
* rdma_hold_gid_attr - Get reference to existing GID attribute
*
* @attr: Pointer to the GID attribute whose reference
* needs to be taken.
*
* Increase the reference count to a GID attribute to keep it from being
* freed. Callers are required to already be holding a reference to attribute.
*
*/
void rdma_hold_gid_attr(const struct ib_gid_attr *attr)
{
struct ib_gid_table_entry *entry =
container_of(attr, struct ib_gid_table_entry, attr);
get_gid_entry(entry);
}
EXPORT_SYMBOL(rdma_hold_gid_attr);
static int config_non_roce_gid_cache(struct ib_device *device, static int config_non_roce_gid_cache(struct ib_device *device,
u8 port, int gid_tbl_len) u8 port, int gid_tbl_len)
{ {

View File

@ -150,4 +150,8 @@ int ib_get_cached_port_state(struct ib_device *device,
enum ib_port_state *port_active); enum ib_port_state *port_active);
bool rdma_is_zero_gid(const union ib_gid *gid); bool rdma_is_zero_gid(const union ib_gid *gid);
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);
#endif /* _IB_CACHE_H */ #endif /* _IB_CACHE_H */