RDMA/core: Introduce IB_MR_TYPE_INTEGRITY and ib_alloc_mr_integrity API

This is a preparation for signature verbs API re-design. In the new
design a single MR with IB_MR_TYPE_INTEGRITY type will be used to perform
the needed mapping for data integrity operations.
Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/core/device.c

@@ -2437,6 +2437,7 @@ void ib_set_device_ops(struct ib_device *dev, const struct ib_device_ops *ops)
 	SET_DEVICE_OP(dev_ops, alloc_fmr);
 	SET_DEVICE_OP(dev_ops, alloc_hw_stats);
 	SET_DEVICE_OP(dev_ops, alloc_mr);
+	SET_DEVICE_OP(dev_ops, alloc_mr_integrity);
 	SET_DEVICE_OP(dev_ops, alloc_mw);
 	SET_DEVICE_OP(dev_ops, alloc_pd);
 	SET_DEVICE_OP(dev_ops, alloc_rdma_netdev);

drivers/infiniband/core/verbs.c

@@ -2011,6 +2011,9 @@ struct ib_mr *ib_alloc_mr_user(struct ib_pd *pd, enum ib_mr_type mr_type,
 	if (!pd->device->ops.alloc_mr)
 		return ERR_PTR(-EOPNOTSUPP);
 
+	if (WARN_ON_ONCE(mr_type == IB_MR_TYPE_INTEGRITY))
+		return ERR_PTR(-EINVAL);
+
 	mr = pd->device->ops.alloc_mr(pd, mr_type, max_num_sg, udata);
 	if (!IS_ERR(mr)) {
 		mr->device  = pd->device;
@@ -2028,6 +2031,49 @@ struct ib_mr *ib_alloc_mr_user(struct ib_pd *pd, enum ib_mr_type mr_type,
 }
 EXPORT_SYMBOL(ib_alloc_mr_user);
 
+/**
+ * ib_alloc_mr_integrity() - Allocates an integrity memory region
+ * @pd:                      protection domain associated with the region
+ * @max_num_data_sg:         maximum data sg entries available for registration
+ * @max_num_meta_sg:         maximum metadata sg entries available for
+ *                           registration
+ *
+ * Notes:
+ * Memory registration page/sg lists must not exceed max_num_sg,
+ * also the integrity page/sg lists must not exceed max_num_meta_sg.
+ *
+ */
+struct ib_mr *ib_alloc_mr_integrity(struct ib_pd *pd,
+				    u32 max_num_data_sg,
+				    u32 max_num_meta_sg)
+{
+	struct ib_mr *mr;
+
+	if (!pd->device->ops.alloc_mr_integrity)
+		return ERR_PTR(-EOPNOTSUPP);
+
+	if (!max_num_meta_sg)
+		return ERR_PTR(-EINVAL);
+
+	mr = pd->device->ops.alloc_mr_integrity(pd, max_num_data_sg,
+						max_num_meta_sg);
+	if (IS_ERR(mr))
+		return mr;
+
+	mr->device = pd->device;
+	mr->pd = pd;
+	mr->dm = NULL;
+	mr->uobject = NULL;
+	atomic_inc(&pd->usecnt);
+	mr->need_inval = false;
+	mr->res.type = RDMA_RESTRACK_MR;
+	rdma_restrack_kadd(&mr->res);
+	mr->type = IB_MR_TYPE_INTEGRITY;
+
+	return mr;
+}
+EXPORT_SYMBOL(ib_alloc_mr_integrity);
+
 /* "Fast" memory regions */
 
 struct ib_fmr *ib_alloc_fmr(struct ib_pd *pd,

include/rdma/ib_verbs.h

@@ -788,6 +788,8 @@ __attribute_const__ int ib_rate_to_mbps(enum ib_rate rate);
  *                            application
  * @IB_MR_TYPE_DMA:           memory region that is used for DMA operations
  *                            without address translations (VA=PA)
+ * @IB_MR_TYPE_INTEGRITY:     memory region that is used for
+ *                            data integrity operations
  */
 enum ib_mr_type {
 	IB_MR_TYPE_MEM_REG,
@@ -796,6 +798,7 @@ enum ib_mr_type {
 	IB_MR_TYPE_DM,
 	IB_MR_TYPE_USER,
 	IB_MR_TYPE_DMA,
+	IB_MR_TYPE_INTEGRITY,
 };
 
 enum ib_mr_status_check {
@@ -2363,6 +2366,9 @@ struct ib_device_ops {
 	int (*dereg_mr)(struct ib_mr *mr, struct ib_udata *udata);
 	struct ib_mr *(*alloc_mr)(struct ib_pd *pd, enum ib_mr_type mr_type,
 				  u32 max_num_sg, struct ib_udata *udata);
+	struct ib_mr *(*alloc_mr_integrity)(struct ib_pd *pd,
+					    u32 max_num_data_sg,
+					    u32 max_num_meta_sg);
 	int (*advise_mr)(struct ib_pd *pd,
 			 enum ib_uverbs_advise_mr_advice advice, u32 flags,
 			 struct ib_sge *sg_list, u32 num_sge,
@@ -4042,6 +4048,10 @@ static inline struct ib_mr *ib_alloc_mr(struct ib_pd *pd,
 	return ib_alloc_mr_user(pd, mr_type, max_num_sg, NULL);
 }
 
+struct ib_mr *ib_alloc_mr_integrity(struct ib_pd *pd,
+				    u32 max_num_data_sg,
+				    u32 max_num_meta_sg);
+
 /**
  * ib_update_fast_reg_key - updates the key portion of the fast_reg MR
  *   R_Key and L_Key.