[PATCH v2 rdma-next] RDMA: Use ERR_CAST to return an error-valued pointer

[PATCH v2 rdma-next] RDMA: Use ERR_CAST to return an error-valued pointer

[Yu Jiaoliang]

Instead of directly casting and returning an error-valued pointer,
use ERR_CAST to make the error handling more explicit and improve
code clarity.

Signed-off-by: Yu Jiaoliang <yujiaoliang@vivo.com>
---
v2:
- Additional modifications in file /drivers/infiniband/hw/irdma/verbs.c
v1: https://lore.kernel.org/all/20240905110615.GU4026@unreal/
---
 drivers/infiniband/core/mad_rmpp.c   | 2 +-
 drivers/infiniband/core/uverbs_cmd.c | 2 +-
 drivers/infiniband/core/verbs.c      | 2 +-
 drivers/infiniband/hw/irdma/verbs.c  | 4 ++--
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/infiniband/core/mad_rmpp.c b/drivers/infiniband/core/mad_rmpp.c
index 8af0619a39cd..b4b10e8a6495 100644
--- a/drivers/infiniband/core/mad_rmpp.c
+++ b/drivers/infiniband/core/mad_rmpp.c
@@ -158,7 +158,7 @@ static struct ib_mad_send_buf *alloc_response_msg(struct ib_mad_agent *agent,
 	ah = ib_create_ah_from_wc(agent->qp->pd, recv_wc->wc,
 				  recv_wc->recv_buf.grh, agent->port_num);
 	if (IS_ERR(ah))
-		return (void *) ah;
+		return ERR_CAST(ah);
 
 	hdr_len = ib_get_mad_data_offset(recv_wc->recv_buf.mad->mad_hdr.mgmt_class);
 	msg = ib_create_send_mad(agent, recv_wc->wc->src_qp,
diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index 1b3ea71f2c33..35a83825f6ba 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -192,7 +192,7 @@ _ib_uverbs_lookup_comp_file(s32 fd, struct uverbs_attr_bundle *attrs)
 					       fd, attrs);
 
 	if (IS_ERR(uobj))
-		return (void *)uobj;
+		return ERR_CAST(uobj);
 
 	uverbs_uobject_get(uobj);
 	uobj_put_read(uobj);
diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index 473ee0831307..77268cce4d31 100644
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -572,7 +572,7 @@ struct ib_ah *rdma_create_ah(struct ib_pd *pd, struct rdma_ah_attr *ah_attr,
 					   GFP_KERNEL : GFP_ATOMIC);
 	if (IS_ERR(slave)) {
 		rdma_unfill_sgid_attr(ah_attr, old_sgid_attr);
-		return (void *)slave;
+		return ERR_CAST(slave);
 	}
 	ah = _rdma_create_ah(pd, ah_attr, flags, NULL, slave);
 	rdma_lag_put_ah_roce_slave(slave);
diff --git a/drivers/infiniband/hw/irdma/verbs.c b/drivers/infiniband/hw/irdma/verbs.c
index 6a107decb704..1ae336800c63 100644
--- a/drivers/infiniband/hw/irdma/verbs.c
+++ b/drivers/infiniband/hw/irdma/verbs.c
@@ -3037,7 +3037,7 @@ static struct ib_mr *irdma_reg_user_mr(struct ib_pd *pd, u64 start, u64 len,
 	if (IS_ERR(region)) {
 		ibdev_dbg(&iwdev->ibdev,
 			  "VERBS: Failed to create ib_umem region\n");
-		return (struct ib_mr *)region;
+		return ERR_CAST(region);
 	}
 
 	if (ib_copy_from_udata(&req, udata, min(sizeof(req), udata->inlen))) {
@@ -3048,7 +3048,7 @@ static struct ib_mr *irdma_reg_user_mr(struct ib_pd *pd, u64 start, u64 len,
 	iwmr = irdma_alloc_iwmr(region, pd, virt, req.reg_type);
 	if (IS_ERR(iwmr)) {
 		ib_umem_release(region);
-		return (struct ib_mr *)iwmr;
+		return ERR_CAST(iwmr);
 	}
 
 	switch (req.reg_type) {
-- 
2.34.1

Re: [PATCH v2 rdma-next] RDMA: Use ERR_CAST to return an error-valued pointer

[Leon Romanovsky]

On Fri, Sep 06, 2024 at 02:21:36PM +0800, Yu Jiaoliang wrote:
> Instead of directly casting and returning an error-valued pointer,
> use ERR_CAST to make the error handling more explicit and improve
> code clarity.
> 
> Signed-off-by: Yu Jiaoliang <yujiaoliang@vivo.com>
> ---
> v2:
> - Additional modifications in file /drivers/infiniband/hw/irdma/verbs.c
> v1: https://lore.kernel.org/all/20240905110615.GU4026@unreal/
> ---
>  drivers/infiniband/core/mad_rmpp.c   | 2 +-
>  drivers/infiniband/core/uverbs_cmd.c | 2 +-
>  drivers/infiniband/core/verbs.c      | 2 +-
>  drivers/infiniband/hw/irdma/verbs.c  | 4 ++--
>  4 files changed, 5 insertions(+), 5 deletions(-)

It is still incomplete.
Something like that will give you a better result:
➜  kernel git:(wip/leon-for-next) git grep "return (" drivers/infiniband/ | grep "\*"

Thanks