IB/rdmavt: Always return ERR_PTR from rvt_create_mmap_info()

The commit below modified rvt_create_mmap_info() to return ERR_PTR's but
didn't update the callers to handle them. Modify rvt_create_mmap_info() to
only return ERR_PTR and fix all error checking after
rvt_create_mmap_info() was called.

Fixes: ff23dfa1 ("IB: Pass only ib_udata in function prototypes")
Link: https://lore.kernel.org/r/20200424173146.10970-1-sudipm.mukherjee@gmail.com
Cc: stable@vger.kernel.org [5.4+]
Tested-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Acked-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/sw/rdmavt/cq.c

@@ -248,8 +248,8 @@ int rvt_create_cq(struct ib_cq *ibcq, const struct ib_cq_init_attr *attr,
 	 */
 	if (udata && udata->outlen >= sizeof(__u64)) {
 		cq->ip = rvt_create_mmap_info(rdi, sz, udata, u_wc);
-		if (!cq->ip) {
-			err = -ENOMEM;
+		if (IS_ERR(cq->ip)) {
+			err = PTR_ERR(cq->ip);
 			goto bail_wc;
 		}
 

drivers/infiniband/sw/rdmavt/mmap.c

@@ -154,7 +154,7 @@ int rvt_mmap(struct ib_ucontext *context, struct vm_area_struct *vma)
  * @udata: user data (must be valid!)
  * @obj: opaque pointer to a cq, wq etc
  *
- * Return: rvt_mmap struct on success
+ * Return: rvt_mmap struct on success, ERR_PTR on failure
  */
 struct rvt_mmap_info *rvt_create_mmap_info(struct rvt_dev_info *rdi, u32 size,
 					   struct ib_udata *udata, void *obj)
@@ -166,7 +166,7 @@ struct rvt_mmap_info *rvt_create_mmap_info(struct rvt_dev_info *rdi, u32 size,
 
 	ip = kmalloc_node(sizeof(*ip), GFP_KERNEL, rdi->dparms.node);
 	if (!ip)
-		return ip;
+		return ERR_PTR(-ENOMEM);
 
 	size = PAGE_ALIGN(size);
 

drivers/infiniband/sw/rdmavt/qp.c

@@ -1244,8 +1244,8 @@ struct ib_qp *rvt_create_qp(struct ib_pd *ibpd,
 
 			qp->ip = rvt_create_mmap_info(rdi, s, udata,
 						      qp->r_rq.wq);
-			if (!qp->ip) {
-				ret = ERR_PTR(-ENOMEM);
+			if (IS_ERR(qp->ip)) {
+				ret = ERR_CAST(qp->ip);
 				goto bail_qpn;
 			}
 

drivers/infiniband/sw/rdmavt/srq.c

@@ -111,8 +111,8 @@ int rvt_create_srq(struct ib_srq *ibsrq, struct ib_srq_init_attr *srq_init_attr,
 		u32 s = sizeof(struct rvt_rwq) + srq->rq.size * sz;
 
 		srq->ip = rvt_create_mmap_info(dev, s, udata, srq->rq.wq);
-		if (!srq->ip) {
-			ret = -ENOMEM;
+		if (IS_ERR(srq->ip)) {
+			ret = PTR_ERR(srq->ip);
 			goto bail_wq;
 		}