scsi: lpfc: avoid harmless comparison warning

When building with -Wextra, we get a lot of warnings for the lpfc driver
concerning expressions that are always true, starting with:

drivers/scsi/lpfc/lpfc_attr.c: In function 'lpfc_enable_npiv_init':
drivers/scsi/lpfc/lpfc_attr.c:2786:77: error: comparison of unsigned expression >= 0 is always true [-Werror=type-limits]
drivers/scsi/lpfc/lpfc_attr.c: In function 'lpfc_enable_rrq_init':
drivers/scsi/lpfc/lpfc_attr.c:2802:76: error: comparison of unsigned expression >= 0 is always true [-Werror=type-limits]
drivers/scsi/lpfc/lpfc_attr.c: In function 'lpfc_suppress_link_up_init':
drivers/scsi/lpfc/lpfc_attr.c:2812:2050: error: comparison of unsigned expression >= 0 is always true [-Werror=type-limits]
drivers/scsi/lpfc/lpfc_attr.c: In function 'lpfc_log_verbose_init':
drivers/scsi/lpfc/lpfc_attr.c:3064:1930: error: comparison of unsigned expression >= 0 is always true [-Werror=type-limits]

The code works as intended, but it would be nice to shut up the warning
so we don't clutter up build logs with this. Using a separate inline
function for it makes it clear to the compiler that the comparison is
necessary in the caller but still lets it do the constant-folding.

[mkp: fix typo]

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Acked-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/lpfc/lpfc_attr.c b/drivers/scsi/lpfc/lpfc_attr.c
index 6793df8..f101990 100644 (file)
--- a/drivers/scsi/lpfc/lpfc_attr.c
+++ b/drivers/scsi/lpfc/lpfc_attr.c
@@ -1621,6 +1621,11 @@ lpfc_sriov_hw_max_virtfn_show(struct device *dev,
        return snprintf(buf, PAGE_SIZE, "%d\n", max_nr_virtfn);
 }
 
+static inline bool lpfc_rangecheck(uint val, uint min, uint max)
+{
+       return val >= min && val <= max;
+}
+
 /**
  * lpfc_param_show - Return a cfg attribute value in decimal
  *
@@ -1698,7 +1703,7 @@ lpfc_##attr##_show(struct device *dev, struct device_attribute *attr, \
 static int \
 lpfc_##attr##_init(struct lpfc_hba *phba, uint val) \
 { \
-       if (val >= minval && val <= maxval) {\
+       if (lpfc_rangecheck(val, minval, maxval)) {\
                phba->cfg_##attr = val;\
                return 0;\
        }\
@@ -1733,7 +1738,7 @@ lpfc_##attr##_init(struct lpfc_hba *phba, uint val) \
 static int \
 lpfc_##attr##_set(struct lpfc_hba *phba, uint val) \
 { \
-       if (val >= minval && val <= maxval) {\
+       if (lpfc_rangecheck(val, minval, maxval)) {\
                lpfc_printf_log(phba, KERN_ERR, LOG_INIT, \
                        "3052 lpfc_" #attr " changed from %d to %d\n", \
                        phba->cfg_##attr, val); \
@@ -1857,7 +1862,7 @@ lpfc_##attr##_show(struct device *dev, struct device_attribute *attr, \
 static int \
 lpfc_##attr##_init(struct lpfc_vport *vport, uint val) \
 { \
-       if (val >= minval && val <= maxval) {\
+       if (lpfc_rangecheck(val, minval, maxval)) {\
                vport->cfg_##attr = val;\
                return 0;\
        }\
@@ -1889,7 +1894,7 @@ lpfc_##attr##_init(struct lpfc_vport *vport, uint val) \
 static int \
 lpfc_##attr##_set(struct lpfc_vport *vport, uint val) \
 { \
-       if (val >= minval && val <= maxval) {\
+       if (lpfc_rangecheck(val, minval, maxval)) {\
                lpfc_printf_vlog(vport, KERN_ERR, LOG_INIT, \
                        "3053 lpfc_" #attr \
                        " changed from %d (x%x) to %d (x%x)\n", \