IB/core: Introduce protected memory regions

This commit introduces verbs for creating/destoying memory
regions which will allow new types of memory key operations such
as protected memory registration.

Indirect memory registration is registering several (one
of more) pre-registered memory regions in a specific layout.
The Indirect region may potentialy describe several regions
and some repitition format between them.

Protected Memory registration is registering a memory region
with various data integrity attributes which will describe protection
schemes that will be handled by the HCA in an offloaded manner.
These memory regions will be applicable for a new REG_SIG_MR
work request introduced later in this patchset.

In the future these routines may replace or implement current memory
regions creation routines existing today:
- ib_reg_user_mr
- ib_alloc_fast_reg_mr
- ib_get_dma_mr
- ib_dereg_mr

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 39 insertions, 0 deletions

diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index 3ac795115438..ca8ce7d097e3 100644
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -1169,6 +1169,45 @@ int ib_dereg_mr(struct ib_mr *mr)
 }
 EXPORT_SYMBOL(ib_dereg_mr);
 
+struct ib_mr *ib_create_mr(struct ib_pd *pd,
+			   struct ib_mr_init_attr *mr_init_attr)
+{
+	struct ib_mr *mr;
+
+	if (!pd->device->create_mr)
+		return ERR_PTR(-ENOSYS);
+
+	mr = pd->device->create_mr(pd, mr_init_attr);
+
+	if (!IS_ERR(mr)) {
+		mr->device  = pd->device;
+		mr->pd      = pd;
+		mr->uobject = NULL;
+		atomic_inc(&pd->usecnt);
+		atomic_set(&mr->usecnt, 0);
+	}
+
+	return mr;
+}
+EXPORT_SYMBOL(ib_create_mr);
+
+int ib_destroy_mr(struct ib_mr *mr)
+{
+	struct ib_pd *pd;
+	int ret;
+
+	if (atomic_read(&mr->usecnt))
+		return -EBUSY;
+
+	pd = mr->pd;
+	ret = mr->device->destroy_mr(mr);
+	if (!ret)
+		atomic_dec(&pd->usecnt);
+
+	return ret;
+}
+EXPORT_SYMBOL(ib_destroy_mr);
+
 struct ib_mr *ib_alloc_fast_reg_mr(struct ib_pd *pd, int max_page_list_len)
 {
 	struct ib_mr *mr;