smcd_buf_free() calls smc_ism_unregister_dmb(lgr->smcd, buf_desc) and
then unconditionally frees buf_desc.

Remove the cleaning up of fields of buf_desc in
smc_ism_unregister_dmb(), because it is not helpful.

This removes the only usage of ISM_ERROR from the smc module. So move it
to drivers/s390/net/ism.h.

Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Mahanta Jambigi <mjambigi@linux.ibm.com>
---
 drivers/s390/net/ism.h |  1 +
 include/net/smc.h      |  2 --
 net/smc/smc_ism.c      | 14 +++++---------
 net/smc/smc_ism.h      |  3 ++-
 4 files changed, 8 insertions(+), 12 deletions(-)

diff --git a/drivers/s390/net/ism.h b/drivers/s390/net/ism.h
index 047fa6101555..b5b03db52fce 100644
--- a/drivers/s390/net/ism.h
+++ b/drivers/s390/net/ism.h
@@ -10,6 +10,7 @@
 #include <asm/pci_insn.h>
 
 #define UTIL_STR_LEN	16
+#define ISM_ERROR	0xFFFF
 
 /*
  * Do not use the first word of the DMB bits to ensure 8 byte aligned access.
diff --git a/include/net/smc.h b/include/net/smc.h
index db84e4e35080..a9c023dd1380 100644
--- a/include/net/smc.h
+++ b/include/net/smc.h
@@ -44,8 +44,6 @@ struct smcd_dmb {
 
 #define ISM_RESERVED_VLANID	0x1FFF
 
-#define ISM_ERROR	0xFFFF
-
 struct smcd_dev;
 
 struct smcd_gid {
diff --git a/net/smc/smc_ism.c b/net/smc/smc_ism.c
index a58ffb7a0610..fca01b95b65a 100644
--- a/net/smc/smc_ism.c
+++ b/net/smc/smc_ism.c
@@ -205,13 +205,13 @@ int smc_ism_put_vlan(struct smcd_dev *smcd, unsigned short vlanid)
 	return rc;
 }
 
-int smc_ism_unregister_dmb(struct smcd_dev *smcd, struct smc_buf_desc *dmb_desc)
+void smc_ism_unregister_dmb(struct smcd_dev *smcd,
+			    struct smc_buf_desc *dmb_desc)
 {
 	struct smcd_dmb dmb;
-	int rc = 0;
 
 	if (!dmb_desc->dma_addr)
-		return rc;
+		return;
 
 	memset(&dmb, 0, sizeof(dmb));
 	dmb.dmb_tok = dmb_desc->token;
@@ -219,13 +219,9 @@ int smc_ism_unregister_dmb(struct smcd_dev *smcd, struct smc_buf_desc *dmb_desc)
 	dmb.cpu_addr = dmb_desc->cpu_addr;
 	dmb.dma_addr = dmb_desc->dma_addr;
 	dmb.dmb_len = dmb_desc->len;
-	rc = smcd->ops->unregister_dmb(smcd, &dmb);
-	if (!rc || rc == ISM_ERROR) {
-		dmb_desc->cpu_addr = NULL;
-		dmb_desc->dma_addr = 0;
-	}
+	smcd->ops->unregister_dmb(smcd, &dmb);
 
-	return rc;
+	return;
 }
 
 int smc_ism_register_dmb(struct smc_link_group *lgr, int dmb_len,
diff --git a/net/smc/smc_ism.h b/net/smc/smc_ism.h
index 6763133dd8d0..765aa8fae6fa 100644
--- a/net/smc/smc_ism.h
+++ b/net/smc/smc_ism.h
@@ -47,7 +47,8 @@ int smc_ism_get_vlan(struct smcd_dev *dev, unsigned short vlan_id);
 int smc_ism_put_vlan(struct smcd_dev *dev, unsigned short vlan_id);
 int smc_ism_register_dmb(struct smc_link_group *lgr, int buf_size,
 			 struct smc_buf_desc *dmb_desc);
-int smc_ism_unregister_dmb(struct smcd_dev *dev, struct smc_buf_desc *dmb_desc);
+void smc_ism_unregister_dmb(struct smcd_dev *dev,
+			    struct smc_buf_desc *dmb_desc);
 bool smc_ism_support_dmb_nocopy(struct smcd_dev *smcd);
 int smc_ism_attach_dmb(struct smcd_dev *dev, u64 token,
 		       struct smc_buf_desc *dmb_desc);
-- 
2.48.1