[PATCH v4] scsi: libfc: Fix passing zero to 'PTR_ERR' warning

[YueHaibing]

drivers/scsi/libfc/fc_disc.c:304
 fc_disc_error() warn: passing zero to 'PTR_ERR'

fp maybe NULL in fc_disc_error(), use PTR_ERR_OR_ZERO to handle this.

Signed-off-by: YueHaibing <yuehaib...@huawei.com>
---
v4: fix error print type 
v3: use PTR_ERR_OR_ZERO
v2: use use IS_ERR in fc_disc_error()
---
 drivers/scsi/libfc/fc_disc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/libfc/fc_disc.c b/drivers/scsi/libfc/fc_disc.c
index e67abb184a8a..942fc60f7c21 100644
--- a/drivers/scsi/libfc/fc_disc.c
+++ b/drivers/scsi/libfc/fc_disc.c
@@ -301,8 +301,8 @@ static void fc_disc_error(struct fc_disc *disc, struct 
fc_frame *fp)
        struct fc_lport *lport = fc_disc_lport(disc);
        unsigned long delay = 0;
 
-       FC_DISC_DBG(disc, "Error %ld, retries %d/%d\n",
-                   PTR_ERR(fp), disc->retry_count,
+       FC_DISC_DBG(disc, "Error %d, retries %d/%d\n",
+                   PTR_ERR_OR_ZERO(fp), disc->retry_count,
                    FC_DISC_RETRY_LIMIT);
 
        if (!fp || PTR_ERR(fp) == -FC_EX_TIMEOUT) {
-- 
2.17.1