net/mlx5: Use bulk allocation for fast update encryption key

net/mlx5: Use bulk allocation for fast update encryption key

We create a pool for each key type. For the pool, there is a struct
to store the info for all DEK objects of one bulk allocation. As we
use crypto->log_dek_obj_range, which is set to 12 in previous patch,
for the log_obj_range of bulk allocation, 4096 DEKs are allocated in
one time.

To trace the state of all the keys in a bulk, two bitmaps are created.
The need_sync bitmap is used to indicate the available state of the
corresponding key. If the bit is 0, it can be used (available) as it
either is newly created by FW, or SYNC_CRYPTO is executed and bit is
reset after it is freed by upper layer user (this is the case to be
handled in later patch). Otherwise, the key need to be synced. The
in_use bitmap is used to indicate the key is being used, and reset
when user free it.

When ktls, ipsec or macsec need a key from a bulk, it get one with
need_sync bit 0, then set both need_sync and in_used bit to 1. When
user free a key, only in_use bit is reset to 0. So, for the
combinations of (need_sync, in_use) of one DEK object,
   - (0,0) means the key is ready for use,
   - (1,1) means the key is currently being used by a user,
   - (1,0) means the key is freed, and waiting for being synced,
   - (0,1) is invalid state.

There are two lists in each pool, partial_list and full_list,
according to the number for available DEKs in a bulk. When user need a
key, it get a bulk, either from partial list, or create new one from
FW. Then the bulk is put in the different pool's lists according to
the num of avail deks it has. If there is no avail deks, and all of
them are be freed by users, for now, the bulk is destroyed.

To speed up the bitmap search, a variable (avail_start) is added to
indicate where to start to search need_sync bitmap for available key.

Signed-off-by: Jianbo Liu <jianbol@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>