[PATCH 09/10] scsi: aic94xx: Remove snprintf() from sysfs call-backs and replace with sysfs_emit()

Lee Jones
2024-02-08T08:45:37Z

Since snprintf() has the documented, but still rather strange trait of
returning the length of the data that *would have been* written to the
array if space were available, rather than the arguably more useful
length of data *actually* written, it is usually considered wise to use
something else instead in order to avoid confusion.

In the case of sysfs call-backs, new wrappers exist that do just that.

Link: https://lwn.net/Articles/69419/
Link: https://github.com/KSPP/linux/issues/105
Signed-off-by: Lee Jones <lee@kernel.org>
---
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Luben Tuikov <luben_tuikov@adaptec.com>
Cc: linux-scsi@vger.kernel.org
---
drivers/scsi/aic94xx/aic94xx_init.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/scsi/aic94xx/aic94xx_init.c b/drivers/scsi/aic94xx/aic94xx_init.c
index 8a3340d8d7ad4..c976e4b77c71e 100644
--- a/drivers/scsi/aic94xx/aic94xx_init.c
+++ b/drivers/scsi/aic94xx/aic94xx_init.c
@@ -264,8 +264,7 @@ static ssize_t asd_show_dev_rev(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct asd_ha_struct *asd_ha = dev_to_asd_ha(dev);
- return snprintf(buf, PAGE_SIZE, "%s\n",
- asd_dev_rev[asd_ha->revision_id]);
+ return sysfs_emit(buf, "%s\n", asd_dev_rev[asd_ha->revision_id]);
}
static DEVICE_ATTR(aic_revision, S_IRUGO, asd_show_dev_rev, NULL);

@@ -273,7 +272,7 @@ static ssize_t asd_show_dev_bios_build(struct device *dev,
struct device_attribute *attr,char *buf)
{
struct asd_ha_struct *asd_ha = dev_to_asd_ha(dev);
- return snprintf(buf, PAGE_SIZE, "%d\n", asd_ha->hw_prof.bios.bld);
+ return sysfs_emit(buf, "%d\n", asd_ha->hw_prof.bios.bld);
}
static DEVICE_ATTR(bios_build, S_IRUGO, asd_show_dev_bios_build, NULL);

@@ -281,7 +280,7 @@ static ssize_t asd_show_dev_pcba_sn(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct asd_ha_struct *asd_ha = dev_to_asd_ha(dev);
- return snprintf(buf, PAGE_SIZE, "%s\n", asd_ha->hw_prof.pcba_sn);
+ return sysfs_emit(buf, "%s\n", asd_ha->hw_prof.pcba_sn);
}
static DEVICE_ATTR(pcba_sn, S_IRUGO, asd_show_dev_pcba_sn, NULL);

@@ -452,7 +451,7 @@ static ssize_t asd_show_update_bios(struct device *dev,
if (asd_ha->bios_status != FLASH_IN_PROGRESS)
asd_ha->bios_status = FLASH_OK;

- return snprintf(buf, PAGE_SIZE, "status=%x %s\n",
+ return sysfs_emit(buf, "status=%x %s\n",
flash_error_table[i].err_code,
flash_error_table[i].reason);
}
@@ -937,7 +936,7 @@ static int asd_scan_finished(struct Scsi_Host *shost, unsigned long time)

static ssize_t version_show(struct device_driver *driver, char *buf)
{
- return snprintf(buf, PAGE_SIZE, "%s\n", ASD_DRIVER_VERSION);
+ return sysfs_emit(buf, "%s\n", ASD_DRIVER_VERSION);
}
static DRIVER_ATTR_RO(version);

--
2.43.0.594.gd9cf4e227d-goog