RDMA, core and ULPs: Declare ib_post_send() and ib_post_recv() argume…

…nts const

Since neither ib_post_send() nor ib_post_recv() modify the data structure
their second argument points at, declare that argument const. This change
makes it necessary to declare the 'bad_wr' argument const too and also to
modify all ULPs that call ib_post_send(), ib_post_recv() or
ib_post_srq_recv(). This patch does not change any functionality but makes
it possible for the compiler to verify whether the
ib_post_(send|recv|srq_recv) really do not modify the posted work request.

To make this possible, only one cast had to be introduce that casts away
constness, namely in rpcrdma_post_recvs(). The only way I can think of to
avoid that cast is to introduce an additional loop in that function or to
change the data type of bad_wr from struct ib_recv_wr ** into int
(an index that refers to an element in the work request list). However,
both approaches would require even more extensive changes than this
patch.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/core/uverbs_cmd.c

@@ -2155,7 +2155,8 @@ ssize_t ib_uverbs_post_send(struct ib_uverbs_file *file,
 	struct ib_uverbs_post_send      cmd;
 	struct ib_uverbs_post_send_resp resp;
 	struct ib_uverbs_send_wr       *user_wr;
-	struct ib_send_wr              *wr = NULL, *last, *next, *bad_wr;
+	struct ib_send_wr              *wr = NULL, *last, *next;
+	const struct ib_send_wr	       *bad_wr;
 	struct ib_qp                   *qp;
 	int                             i, sg_ind;
 	int				is_ud;
@@ -2434,7 +2435,8 @@ ssize_t ib_uverbs_post_recv(struct ib_uverbs_file *file,
 {
 	struct ib_uverbs_post_recv      cmd;
 	struct ib_uverbs_post_recv_resp resp;
-	struct ib_recv_wr              *wr, *next, *bad_wr;
+	struct ib_recv_wr              *wr, *next;
+	const struct ib_recv_wr	       *bad_wr;
 	struct ib_qp                   *qp;
 	ssize_t                         ret = -EINVAL;
 
@@ -2483,7 +2485,8 @@ ssize_t ib_uverbs_post_srq_recv(struct ib_uverbs_file *file,
 {
 	struct ib_uverbs_post_srq_recv      cmd;
 	struct ib_uverbs_post_srq_recv_resp resp;
-	struct ib_recv_wr                  *wr, *next, *bad_wr;
+	struct ib_recv_wr                  *wr, *next;
+	const struct ib_recv_wr		   *bad_wr;
 	struct ib_srq                      *srq;
 	ssize_t                             ret = -EINVAL;
 

drivers/infiniband/hw/bnxt_re/ib_verbs.c

@@ -1519,8 +1519,8 @@ int bnxt_re_query_srq(struct ib_srq *ib_srq, struct ib_srq_attr *srq_attr)
 	return 0;
 }
 
-int bnxt_re_post_srq_recv(struct ib_srq *ib_srq, struct ib_recv_wr *wr,
-			  struct ib_recv_wr **bad_wr)
+int bnxt_re_post_srq_recv(struct ib_srq *ib_srq, const struct ib_recv_wr *wr,
+			  const struct ib_recv_wr **bad_wr)
 {
 	struct bnxt_re_srq *srq = container_of(ib_srq, struct bnxt_re_srq,
 					       ib_srq);
@@ -2048,7 +2048,7 @@ static int bnxt_re_build_qp1_send_v2(struct bnxt_re_qp *qp,
  * and the MAD datagram out to the provided SGE.
  */
 static int bnxt_re_build_qp1_shadow_qp_recv(struct bnxt_re_qp *qp,
-					    struct ib_recv_wr *wr,
+					    const struct ib_recv_wr *wr,
 					    struct bnxt_qplib_swqe *wqe,
 					    int payload_size)
 {
@@ -2361,8 +2361,8 @@ static int bnxt_re_post_send_shadow_qp(struct bnxt_re_dev *rdev,
 	return rc;
 }
 
-int bnxt_re_post_send(struct ib_qp *ib_qp, struct ib_send_wr *wr,
-		      struct ib_send_wr **bad_wr)
+int bnxt_re_post_send(struct ib_qp *ib_qp, const struct ib_send_wr *wr,
+		      const struct ib_send_wr **bad_wr)
 {
 	struct bnxt_re_qp *qp = container_of(ib_qp, struct bnxt_re_qp, ib_qp);
 	struct bnxt_qplib_swqe wqe;
@@ -2461,7 +2461,7 @@ int bnxt_re_post_send(struct ib_qp *ib_qp, struct ib_send_wr *wr,
 
 static int bnxt_re_post_recv_shadow_qp(struct bnxt_re_dev *rdev,
 				       struct bnxt_re_qp *qp,
-				       struct ib_recv_wr *wr)
+				       const struct ib_recv_wr *wr)
 {
 	struct bnxt_qplib_swqe wqe;
 	int rc = 0;
@@ -2494,8 +2494,8 @@ static int bnxt_re_post_recv_shadow_qp(struct bnxt_re_dev *rdev,
 	return rc;
 }
 
-int bnxt_re_post_recv(struct ib_qp *ib_qp, struct ib_recv_wr *wr,
-		      struct ib_recv_wr **bad_wr)
+int bnxt_re_post_recv(struct ib_qp *ib_qp, const struct ib_recv_wr *wr,
+		      const struct ib_recv_wr **bad_wr)
 {
 	struct bnxt_re_qp *qp = container_of(ib_qp, struct bnxt_re_qp, ib_qp);
 	struct bnxt_qplib_swqe wqe;

drivers/infiniband/hw/bnxt_re/ib_verbs.h

@@ -181,8 +181,8 @@ int bnxt_re_modify_srq(struct ib_srq *srq, struct ib_srq_attr *srq_attr,
 		       struct ib_udata *udata);
 int bnxt_re_query_srq(struct ib_srq *srq, struct ib_srq_attr *srq_attr);
 int bnxt_re_destroy_srq(struct ib_srq *srq);
-int bnxt_re_post_srq_recv(struct ib_srq *srq, struct ib_recv_wr *recv_wr,
-			  struct ib_recv_wr **bad_recv_wr);
+int bnxt_re_post_srq_recv(struct ib_srq *srq, const struct ib_recv_wr *recv_wr,
+			  const struct ib_recv_wr **bad_recv_wr);
 struct ib_qp *bnxt_re_create_qp(struct ib_pd *pd,
 				struct ib_qp_init_attr *qp_init_attr,
 				struct ib_udata *udata);
@@ -191,10 +191,10 @@ int bnxt_re_modify_qp(struct ib_qp *qp, struct ib_qp_attr *qp_attr,
 int bnxt_re_query_qp(struct ib_qp *qp, struct ib_qp_attr *qp_attr,
 		     int qp_attr_mask, struct ib_qp_init_attr *qp_init_attr);
 int bnxt_re_destroy_qp(struct ib_qp *qp);
-int bnxt_re_post_send(struct ib_qp *qp, struct ib_send_wr *send_wr,
-		      struct ib_send_wr **bad_send_wr);
-int bnxt_re_post_recv(struct ib_qp *qp, struct ib_recv_wr *recv_wr,
-		      struct ib_recv_wr **bad_recv_wr);
+int bnxt_re_post_send(struct ib_qp *qp, const struct ib_send_wr *send_wr,
+		      const struct ib_send_wr **bad_send_wr);
+int bnxt_re_post_recv(struct ib_qp *qp, const struct ib_recv_wr *recv_wr,
+		      const struct ib_recv_wr **bad_recv_wr);
 struct ib_cq *bnxt_re_create_cq(struct ib_device *ibdev,
 				const struct ib_cq_init_attr *attr,
 				struct ib_ucontext *context,

drivers/infiniband/hw/cxgb3/iwch_provider.h

@@ -326,10 +326,10 @@ enum iwch_qp_query_flags {
 };
 
 u16 iwch_rqes_posted(struct iwch_qp *qhp);
-int iwch_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
-		      struct ib_send_wr **bad_wr);
-int iwch_post_receive(struct ib_qp *ibqp, struct ib_recv_wr *wr,
-		      struct ib_recv_wr **bad_wr);
+int iwch_post_send(struct ib_qp *ibqp, const struct ib_send_wr *wr,
+		   const struct ib_send_wr **bad_wr);
+int iwch_post_receive(struct ib_qp *ibqp, const struct ib_recv_wr *wr,
+		      const struct ib_recv_wr **bad_wr);
 int iwch_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *wc);
 int iwch_post_terminate(struct iwch_qp *qhp, struct respQ_msg_t *rsp_msg);
 int iwch_post_zb_read(struct iwch_ep *ep);

drivers/infiniband/hw/cxgb3/iwch_qp.c

@@ -246,7 +246,7 @@ static int iwch_sgl2pbl_map(struct iwch_dev *rhp, struct ib_sge *sg_list,
 }
 
 static int build_rdma_recv(struct iwch_qp *qhp, union t3_wr *wqe,
-				struct ib_recv_wr *wr)
+			   const struct ib_recv_wr *wr)
 {
 	int i, err = 0;
 	u32 pbl_addr[T3_MAX_SGE];
@@ -286,7 +286,7 @@ static int build_rdma_recv(struct iwch_qp *qhp, union t3_wr *wqe,
 }
 
 static int build_zero_stag_recv(struct iwch_qp *qhp, union t3_wr *wqe,
-				struct ib_recv_wr *wr)
+				const struct ib_recv_wr *wr)
 {
 	int i;
 	u32 pbl_addr;
@@ -348,8 +348,8 @@ static int build_zero_stag_recv(struct iwch_qp *qhp, union t3_wr *wqe,
 	return 0;
 }
 
-int iwch_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
-		      struct ib_send_wr **bad_wr)
+int iwch_post_send(struct ib_qp *ibqp, const struct ib_send_wr *wr,
+		   const struct ib_send_wr **bad_wr)
 {
 	int err = 0;
 	u8 uninitialized_var(t3_wr_flit_cnt);
@@ -463,8 +463,8 @@ int iwch_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
 	return err;
 }
 
-int iwch_post_receive(struct ib_qp *ibqp, struct ib_recv_wr *wr,
-		      struct ib_recv_wr **bad_wr)
+int iwch_post_receive(struct ib_qp *ibqp, const struct ib_recv_wr *wr,
+		      const struct ib_recv_wr **bad_wr)
 {
 	int err = 0;
 	struct iwch_qp *qhp;

drivers/infiniband/hw/cxgb4/iw_cxgb4.h

@@ -1033,10 +1033,10 @@ void c4iw_release_dev_ucontext(struct c4iw_rdev *rdev,
 void c4iw_init_dev_ucontext(struct c4iw_rdev *rdev,
 			    struct c4iw_dev_ucontext *uctx);
 int c4iw_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *wc);
-int c4iw_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
-		      struct ib_send_wr **bad_wr);
-int c4iw_post_receive(struct ib_qp *ibqp, struct ib_recv_wr *wr,
-		      struct ib_recv_wr **bad_wr);
+int c4iw_post_send(struct ib_qp *ibqp, const struct ib_send_wr *wr,
+		   const struct ib_send_wr **bad_wr);
+int c4iw_post_receive(struct ib_qp *ibqp, const struct ib_recv_wr *wr,
+		      const struct ib_recv_wr **bad_wr);
 int c4iw_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *conn_param);
 int c4iw_create_listen(struct iw_cm_id *cm_id, int backlog);
 int c4iw_destroy_listen(struct iw_cm_id *cm_id);
@@ -1119,8 +1119,8 @@ void c4iw_invalidate_mr(struct c4iw_dev *rhp, u32 rkey);
 void c4iw_dispatch_srq_limit_reached_event(struct c4iw_srq *srq);
 void c4iw_copy_wr_to_srq(struct t4_srq *srq, union t4_recv_wr *wqe, u8 len16);
 void c4iw_flush_srqidx(struct c4iw_qp *qhp, u32 srqidx);
-int c4iw_post_srq_recv(struct ib_srq *ibsrq, struct ib_recv_wr *wr,
-		       struct ib_recv_wr **bad_wr);
+int c4iw_post_srq_recv(struct ib_srq *ibsrq, const struct ib_recv_wr *wr,
+		       const struct ib_recv_wr **bad_wr);
 struct c4iw_wr_wait *c4iw_alloc_wr_wait(gfp_t gfp);
 
 typedef int c4iw_restrack_func(struct sk_buff *msg,

drivers/infiniband/hw/cxgb4/qp.c

@@ -620,7 +620,7 @@ static int build_rdma_read(union t4_wr *wqe, const struct ib_send_wr *wr,
 }
 
 static int build_rdma_recv(struct c4iw_qp *qhp, union t4_recv_wr *wqe,
-			   struct ib_recv_wr *wr, u8 *len16)
+			   const struct ib_recv_wr *wr, u8 *len16)
 {
 	int ret;
 
@@ -634,7 +634,7 @@ static int build_rdma_recv(struct c4iw_qp *qhp, union t4_recv_wr *wqe,
 	return 0;
 }
 
-static int build_srq_recv(union t4_recv_wr *wqe, struct ib_recv_wr *wr,
+static int build_srq_recv(union t4_recv_wr *wqe, const struct ib_recv_wr *wr,
 			  u8 *len16)
 {
 	int ret;
@@ -903,8 +903,9 @@ static int complete_sq_drain_wr(struct c4iw_qp *qhp,
 	return 0;
 }
 
-static int complete_sq_drain_wrs(struct c4iw_qp *qhp, struct ib_send_wr *wr,
-				struct ib_send_wr **bad_wr)
+static int complete_sq_drain_wrs(struct c4iw_qp *qhp,
+				 const struct ib_send_wr *wr,
+				 const struct ib_send_wr **bad_wr)
 {
 	int ret = 0;
 
@@ -919,7 +920,8 @@ static int complete_sq_drain_wrs(struct c4iw_qp *qhp, struct ib_send_wr *wr,
 	return ret;
 }
 
-static void complete_rq_drain_wr(struct c4iw_qp *qhp, struct ib_recv_wr *wr)
+static void complete_rq_drain_wr(struct c4iw_qp *qhp,
+				 const struct ib_recv_wr *wr)
 {
 	struct t4_cqe cqe = {};
 	struct c4iw_cq *rchp;
@@ -951,16 +953,17 @@ static void complete_rq_drain_wr(struct c4iw_qp *qhp, struct ib_recv_wr *wr)
 	}
 }
 
-static void complete_rq_drain_wrs(struct c4iw_qp *qhp, struct ib_recv_wr *wr)
+static void complete_rq_drain_wrs(struct c4iw_qp *qhp,
+				  const struct ib_recv_wr *wr)
 {
 	while (wr) {
 		complete_rq_drain_wr(qhp, wr);
 		wr = wr->next;
 	}
 }
 
-int c4iw_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
-		   struct ib_send_wr **bad_wr)
+int c4iw_post_send(struct ib_qp *ibqp, const struct ib_send_wr *wr,
+		   const struct ib_send_wr **bad_wr)
 {
 	int err = 0;
 	u8 len16 = 0;
@@ -1110,8 +1113,8 @@ int c4iw_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
 	return err;
 }
 
-int c4iw_post_receive(struct ib_qp *ibqp, struct ib_recv_wr *wr,
-		      struct ib_recv_wr **bad_wr)
+int c4iw_post_receive(struct ib_qp *ibqp, const struct ib_recv_wr *wr,
+		      const struct ib_recv_wr **bad_wr)
 {
 	int err = 0;
 	struct c4iw_qp *qhp;
@@ -1206,8 +1209,8 @@ static void defer_srq_wr(struct t4_srq *srq, union t4_recv_wr *wqe,
 	t4_srq_produce_pending_wr(srq);
 }
 
-int c4iw_post_srq_recv(struct ib_srq *ibsrq, struct ib_recv_wr *wr,
-		       struct ib_recv_wr **bad_wr)
+int c4iw_post_srq_recv(struct ib_srq *ibsrq, const struct ib_recv_wr *wr,
+		       const struct ib_recv_wr **bad_wr)
 {
 	union t4_recv_wr *wqe, lwqe;
 	struct c4iw_srq *srq;

drivers/infiniband/hw/hns/hns_roce_device.h

@@ -763,10 +763,10 @@ struct hns_roce_hw {
 			 int attr_mask, enum ib_qp_state cur_state,
 			 enum ib_qp_state new_state);
 	int (*destroy_qp)(struct ib_qp *ibqp);
-	int (*post_send)(struct ib_qp *ibqp, struct ib_send_wr *wr,
-			 struct ib_send_wr **bad_wr);
-	int (*post_recv)(struct ib_qp *qp, struct ib_recv_wr *recv_wr,
-			 struct ib_recv_wr **bad_recv_wr);
+	int (*post_send)(struct ib_qp *ibqp, const struct ib_send_wr *wr,
+			 const struct ib_send_wr **bad_wr);
+	int (*post_recv)(struct ib_qp *qp, const struct ib_recv_wr *recv_wr,
+			 const struct ib_recv_wr **bad_recv_wr);
 	int (*req_notify_cq)(struct ib_cq *ibcq, enum ib_cq_notify_flags flags);
 	int (*poll_cq)(struct ib_cq *ibcq, int num_entries, struct ib_wc *wc);
 	int (*dereg_mr)(struct hns_roce_dev *hr_dev, struct hns_roce_mr *mr);

drivers/infiniband/hw/hns/hns_roce_hw_v1.c

@@ -58,8 +58,9 @@ static void set_raddr_seg(struct hns_roce_wqe_raddr_seg *rseg, u64 remote_addr,
 	rseg->len   = 0;
 }
 
-static int hns_roce_v1_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
-				 struct ib_send_wr **bad_wr)
+static int hns_roce_v1_post_send(struct ib_qp *ibqp,
+				 const struct ib_send_wr *wr,
+				 const struct ib_send_wr **bad_wr)
 {
 	struct hns_roce_dev *hr_dev = to_hr_dev(ibqp->device);
 	struct hns_roce_ah *ah = to_hr_ah(ud_wr(wr)->ah);
@@ -342,8 +343,9 @@ static int hns_roce_v1_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
 	return ret;
 }
 
-static int hns_roce_v1_post_recv(struct ib_qp *ibqp, struct ib_recv_wr *wr,
-				 struct ib_recv_wr **bad_wr)
+static int hns_roce_v1_post_recv(struct ib_qp *ibqp,
+				 const struct ib_recv_wr *wr,
+				 const struct ib_recv_wr **bad_wr)
 {
 	int ret = 0;
 	int nreq = 0;
@@ -993,7 +995,8 @@ static int hns_roce_v1_send_lp_wqe(struct hns_roce_qp *hr_qp)
 {
 	struct hns_roce_dev *hr_dev = to_hr_dev(hr_qp->ibqp.device);
 	struct device *dev = &hr_dev->pdev->dev;
-	struct ib_send_wr send_wr, *bad_wr;
+	struct ib_send_wr send_wr;
+	const struct ib_send_wr *bad_wr;
 	int ret;
 
 	memset(&send_wr, 0, sizeof(send_wr));

drivers/infiniband/hw/hns/hns_roce_hw_v2.c

@@ -103,7 +103,7 @@ static void set_extend_sge(struct hns_roce_qp *qp, const struct ib_send_wr *wr,
 static int set_rwqe_data_seg(struct ib_qp *ibqp, const struct ib_send_wr *wr,
 			     struct hns_roce_v2_rc_send_wqe *rc_sq_wqe,
 			     void *wqe, unsigned int *sge_ind,
-			     struct ib_send_wr **bad_wr)
+			     const struct ib_send_wr **bad_wr)
 {
 	struct hns_roce_dev *hr_dev = to_hr_dev(ibqp->device);
 	struct hns_roce_v2_wqe_data_seg *dseg = wqe;
@@ -164,8 +164,9 @@ static int set_rwqe_data_seg(struct ib_qp *ibqp, const struct ib_send_wr *wr,
 	return 0;
 }
 
-static int hns_roce_v2_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
-				 struct ib_send_wr **bad_wr)
+static int hns_roce_v2_post_send(struct ib_qp *ibqp,
+				 const struct ib_send_wr *wr,
+				 const struct ib_send_wr **bad_wr)
 {
 	struct hns_roce_dev *hr_dev = to_hr_dev(ibqp->device);
 	struct hns_roce_ah *ah = to_hr_ah(ud_wr(wr)->ah);
@@ -530,8 +531,9 @@ static int hns_roce_v2_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
 	return ret;
 }
 
-static int hns_roce_v2_post_recv(struct ib_qp *ibqp, struct ib_recv_wr *wr,
-				 struct ib_recv_wr **bad_wr)
+static int hns_roce_v2_post_recv(struct ib_qp *ibqp,
+				 const struct ib_recv_wr *wr,
+				 const struct ib_recv_wr **bad_wr)
 {
 	struct hns_roce_dev *hr_dev = to_hr_dev(ibqp->device);
 	struct hns_roce_qp *hr_qp = to_hr_qp(ibqp);

drivers/infiniband/hw/i40iw/i40iw_verbs.c

@@ -2201,8 +2201,8 @@ static void i40iw_copy_sg_list(struct i40iw_sge *sg_list, struct ib_sge *sgl, in
  * @bad_wr: return of bad wr if err
  */
 static int i40iw_post_send(struct ib_qp *ibqp,
-			   struct ib_send_wr *ib_wr,
-			   struct ib_send_wr **bad_wr)
+			   const struct ib_send_wr *ib_wr,
+			   const struct ib_send_wr **bad_wr)
 {
 	struct i40iw_qp *iwqp;
 	struct i40iw_qp_uk *ukqp;
@@ -2377,9 +2377,8 @@ static int i40iw_post_send(struct ib_qp *ibqp,
  * @ib_wr: work request for receive
  * @bad_wr: bad wr caused an error
  */
-static int i40iw_post_recv(struct ib_qp *ibqp,
-			   struct ib_recv_wr *ib_wr,
-			   struct ib_recv_wr **bad_wr)
+static int i40iw_post_recv(struct ib_qp *ibqp, const struct ib_recv_wr *ib_wr,
+			   const struct ib_recv_wr **bad_wr)
 {
 	struct i40iw_qp *iwqp;
 	struct i40iw_qp_uk *ukqp;