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>
diff --git a/drivers/infiniband/hw/mlx5/mem.c b/drivers/infiniband/hw/mlx5/mem.c
index 5f7b301..b56e4c5 100644
--- a/drivers/infiniband/hw/mlx5/mem.c
+++ b/drivers/infiniband/hw/mlx5/mem.c
@@ -140,12 +140,16 @@
* dev - mlx5_ib device
* umem - umem to use to fill the pages
* page_shift - determines the page size used in the resulting array
+ * offset - offset into the umem to start from,
+ * only implemented for ODP umems
+ * num_pages - total number of pages to fill
* pas - bus addresses array to fill
* access_flags - access flags to set on all present pages.
use enum mlx5_ib_mtt_access_flags for this.
*/
-void mlx5_ib_populate_pas(struct mlx5_ib_dev *dev, struct ib_umem *umem,
- int page_shift, __be64 *pas, int access_flags)
+void __mlx5_ib_populate_pas(struct mlx5_ib_dev *dev, struct ib_umem *umem,
+ int page_shift, size_t offset, size_t num_pages,
+ __be64 *pas, int access_flags)
{
unsigned long umem_page_shift = ilog2(umem->page_size);
int shift = page_shift - umem_page_shift;
@@ -160,13 +164,11 @@
const bool odp = umem->odp_data != NULL;
if (odp) {
- int num_pages = ib_umem_num_pages(umem);
-
WARN_ON(shift != 0);
WARN_ON(access_flags != (MLX5_IB_MTT_READ | MLX5_IB_MTT_WRITE));
for (i = 0; i < num_pages; ++i) {
- dma_addr_t pa = umem->odp_data->dma_list[i];
+ dma_addr_t pa = umem->odp_data->dma_list[offset + i];
pas[i] = cpu_to_be64(umem_dma_to_mtt(pa));
}
@@ -194,6 +196,13 @@
}
}
+void mlx5_ib_populate_pas(struct mlx5_ib_dev *dev, struct ib_umem *umem,
+ int page_shift, __be64 *pas, int access_flags)
+{
+ return __mlx5_ib_populate_pas(dev, umem, page_shift, 0,
+ ib_umem_num_pages(umem), pas,
+ access_flags);
+}
int mlx5_ib_get_buf_offset(u64 addr, int page_shift, u32 *offset)
{
u64 page_size;