RDMA/restrack: Count references to the verbs objects

Refactor the restrack code to make sure the kref inside the restrack entry
properly kref's the object in which it is embedded. This slight change is
needed for future conversions of MR and QP which are refcounted before the
release and kfree.

The ideal flow from ib_core perspective as follows:
* Allocate ib_* structure with rdma_zalloc_*.
* Set everything that is known to ib_core to that newly created object.
* Initialize kref with restrack help
* Call to driver specific allocation functions.
* Insert into restrack DB
....
* Return and release restrack with restrack_put.

Largely this means a rdma_restrack_new() should be called near allocating
the containing structure.

Link: https://lore.kernel.org/r/20200922091106.2152715-4-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

1 files changed, 11 insertions, 7 deletions

diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index d0c3767b0f9f..2607c410b09f 100644
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -272,11 +272,12 @@ struct ib_pd *__ib_alloc_pd(struct ib_device *device, unsigned int flags,
 	atomic_set(&pd->usecnt, 0);
 	pd->flags = flags;
 
-	pd->res.type = RDMA_RESTRACK_PD;
+	rdma_restrack_new(&pd->res, RDMA_RESTRACK_PD);
 	rdma_restrack_set_task(&pd->res, caller);
 
 	ret = device->ops.alloc_pd(pd, NULL);
 	if (ret) {
+		rdma_restrack_put(&pd->res);
 		kfree(pd);
 		return ERR_PTR(ret);
 	}
@@ -1996,11 +1997,13 @@ struct ib_cq *__ib_create_cq(struct ib_device *device,
 	cq->event_handler = event_handler;
 	cq->cq_context = cq_context;
 	atomic_set(&cq->usecnt, 0);
-	cq->res.type = RDMA_RESTRACK_CQ;
+
+	rdma_restrack_new(&cq->res, RDMA_RESTRACK_CQ);
 	rdma_restrack_set_task(&cq->res, caller);
 
 	ret = device->ops.create_cq(cq, cq_attr, NULL);
 	if (ret) {
+		rdma_restrack_put(&cq->res);
 		kfree(cq);
 		return ERR_PTR(ret);
 	}
@@ -2076,7 +2079,8 @@ struct ib_mr *ib_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
 	mr->pd = pd;
 	mr->dm = NULL;
 	atomic_inc(&pd->usecnt);
-	mr->res.type = RDMA_RESTRACK_MR;
+
+	rdma_restrack_new(&mr->res, RDMA_RESTRACK_MR);
 	rdma_restrack_kadd(&mr->res);
 
 	return mr;
@@ -2156,11 +2160,11 @@ struct ib_mr *ib_alloc_mr(struct ib_pd *pd, enum ib_mr_type mr_type,
 	mr->uobject = NULL;
 	atomic_inc(&pd->usecnt);
 	mr->need_inval = false;
-	mr->res.type = RDMA_RESTRACK_MR;
-	rdma_restrack_kadd(&mr->res);
 	mr->type = mr_type;
 	mr->sig_attrs = NULL;
 
+	rdma_restrack_new(&mr->res, RDMA_RESTRACK_MR);
+	rdma_restrack_kadd(&mr->res);
 out:
 	trace_mr_alloc(pd, mr_type, max_num_sg, mr);
 	return mr;
@@ -2216,11 +2220,11 @@ struct ib_mr *ib_alloc_mr_integrity(struct ib_pd *pd,
 	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;
 	mr->sig_attrs = sig_attrs;
 
+	rdma_restrack_new(&mr->res, RDMA_RESTRACK_MR);
+	rdma_restrack_kadd(&mr->res);
 out:
 	trace_mr_integ_alloc(pd, max_num_data_sg, max_num_meta_sg, mr);
 	return mr;