IB/mlx5: Add mlx5_ib_update_mtt to update page tables after creation

The new function allows updating the page tables of a memory region
after it was created. This can be used to handle page faults and page
invalidations.

Since mlx5_ib_update_mtt will need to work from within page invalidation,
so it must not block on memory allocation. It employs an atomic memory
allocation mechanism that is used as a fallback when kmalloc(GFP_ATOMIC) fails.

In order to reuse code from mlx5_ib_populate_pas, the patch splits
this function and add the needed parameters.

Signed-off-by: Haggai Eran <haggaie@mellanox.com>
Signed-off-by: Shachar Raindel <raindel@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/mlx5/device.h b/include/linux/mlx5/device.h
index 64512a7354cb..4e5bd813bb9a 100644
--- a/include/linux/mlx5/device.h
+++ b/include/linux/mlx5/device.h
@@ -200,6 +200,7 @@ enum {
 
 #define MLX5_UMR_MTT_ALIGNMENT 0x40
 #define MLX5_UMR_MTT_MASK      (MLX5_UMR_MTT_ALIGNMENT - 1)
+#define MLX5_UMR_MTT_MIN_CHUNK_SIZE MLX5_UMR_MTT_ALIGNMENT
 
 enum mlx5_event {
         MLX5_EVENT_TYPE_COMP               = 0x0,