net/mlx4_core: Implement resource quota enforcement

Implements resource quota grant decision when resources are requested,
for the following resources:  QPs, CQs, SRQs, MPTs, MTTs, vlans, MACs,
and Counters.

When granting a resource, the quota system increases the allocated-count
for that slave.

When the slave later frees the resource, its allocated-count is reduced.

A spinlock is used to protect the integrity of each resource's free-pool counter.
(One slave may be in the process of being granted a resource while another
slave has crashed, initiating cleanup of that slave's resource quotas).

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx4/mlx4.h

@@ -505,6 +505,7 @@ struct slave_list {
 };
 
 struct resource_allocator {
+	spinlock_t alloc_lock; /* protect quotas */
 	union {
 		int res_reserved;
 		int res_port_rsvd[MLX4_MAX_PORTS];