scsi: 3w-xxxx: Remove snprintf() from sysfs call-backs and replace with sysfs_emit()

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: KSPP/linux#105
Cc: Adam Radford <[email protected]>
Cc: Joel Jacobson <[email protected]>
Cc: de Melo <[email protected]>
Cc: Andre Hedrick <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Martin K. Petersen <[email protected]>

Author: lag-linaro

drivers/scsi/3w-xxxx.c

@@ -496,28 +496,28 @@ static ssize_t tw_show_stats(struct device *dev, struct device_attribute *attr,
 	ssize_t len;
 
 	spin_lock_irqsave(tw_dev->host->host_lock, flags);
-	len = snprintf(buf, PAGE_SIZE, "3w-xxxx Driver version: %s\n"
-		       "Current commands posted:   %4d\n"
-		       "Max commands posted:       %4d\n"
-		       "Current pending commands:  %4d\n"
-		       "Max pending commands:      %4d\n"
-		       "Last sgl length:           %4d\n"
-		       "Max sgl length:            %4d\n"
-		       "Last sector count:         %4d\n"
-		       "Max sector count:          %4d\n"
-		       "SCSI Host Resets:          %4d\n"
-		       "AEN's:                     %4d\n", 
-		       TW_DRIVER_VERSION,
-		       tw_dev->posted_request_count,
-		       tw_dev->max_posted_request_count,
-		       tw_dev->pending_request_count,
-		       tw_dev->max_pending_request_count,
-		       tw_dev->sgl_entries,
-		       tw_dev->max_sgl_entries,
-		       tw_dev->sector_count,
-		       tw_dev->max_sector_count,
-		       tw_dev->num_resets,
-		       tw_dev->aen_count);
+	len = sysfs_emit(buf, "3w-xxxx Driver version: %s\n"
+			 "Current commands posted:   %4d\n"
+			 "Max commands posted:       %4d\n"
+			 "Current pending commands:  %4d\n"
+			 "Max pending commands:      %4d\n"
+			 "Last sgl length:           %4d\n"
+			 "Max sgl length:            %4d\n"
+			 "Last sector count:         %4d\n"
+			 "Max sector count:          %4d\n"
+			 "SCSI Host Resets:          %4d\n"
+			 "AEN's:                     %4d\n",
+			 TW_DRIVER_VERSION,
+			 tw_dev->posted_request_count,
+			 tw_dev->max_posted_request_count,
+			 tw_dev->pending_request_count,
+			 tw_dev->max_pending_request_count,
+			 tw_dev->sgl_entries,
+			 tw_dev->max_sgl_entries,
+			 tw_dev->sector_count,
+			 tw_dev->max_sector_count,
+			 tw_dev->num_resets,
+			 tw_dev->aen_count);
 	spin_unlock_irqrestore(tw_dev->host->host_lock, flags);
 	return len;
 } /* End tw_show_stats() */