block: Replace sprintf() with sysfs_emit()

Per Documentation/filesystems/sysfs.rst, show() should only use
sysfs_emit() or sysfs_emit_at() when formatting the value to be
returned to user space.

No functional change intended.

Signed-off-by: zhangguopeng <zhangguopeng@kylinos.cn>
Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20241107104258.29742-1-zhangguopeng@kylinos.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/blk-sysfs.c

@@ -30,7 +30,7 @@ struct queue_sysfs_entry {
 static ssize_t
 queue_var_show(unsigned long var, char *page)
 {
-	return sprintf(page, "%lu\n", var);
+	return sysfs_emit(page, "%lu\n", var);
 }
 
 static ssize_t
@@ -121,7 +121,7 @@ QUEUE_SYSFS_LIMIT_SHOW(atomic_write_unit_max)
 #define QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_BYTES(_field)			\
 static ssize_t queue_##_field##_show(struct gendisk *disk, char *page)	\
 {									\
-	return sprintf(page, "%llu\n",					\
+	return sysfs_emit(page, "%llu\n",				\
 		(unsigned long long)disk->queue->limits._field <<	\
 			SECTOR_SHIFT);					\
 }
@@ -144,7 +144,7 @@ QUEUE_SYSFS_LIMIT_SHOW_SECTORS_TO_KB(max_hw_sectors)
 #define QUEUE_SYSFS_SHOW_CONST(_name, _val)				\
 static ssize_t queue_##_name##_show(struct gendisk *disk, char *page)	\
 {									\
-	return sprintf(page, "%d\n", _val);				\
+	return sysfs_emit(page, "%d\n", _val);				\
 }
 
 /* deprecated fields */
@@ -235,7 +235,7 @@ static ssize_t queue_feature_store(struct gendisk *disk, const char *page,
 #define QUEUE_SYSFS_FEATURE(_name, _feature)				\
 static ssize_t queue_##_name##_show(struct gendisk *disk, char *page)	\
 {									\
-	return sprintf(page, "%u\n",					\
+	return sysfs_emit(page, "%u\n",					\
 		!!(disk->queue->limits.features & _feature));		\
 }									\
 static ssize_t queue_##_name##_store(struct gendisk *disk,		\
@@ -252,7 +252,7 @@ QUEUE_SYSFS_FEATURE(stable_writes, BLK_FEAT_STABLE_WRITES);
 #define QUEUE_SYSFS_FEATURE_SHOW(_name, _feature)			\
 static ssize_t queue_##_name##_show(struct gendisk *disk, char *page)	\
 {									\
-	return sprintf(page, "%u\n",					\
+	return sysfs_emit(page, "%u\n",					\
 		!!(disk->queue->limits.features & _feature));		\
 }
 
@@ -263,8 +263,8 @@ QUEUE_SYSFS_FEATURE_SHOW(dax, BLK_FEAT_DAX);
 static ssize_t queue_zoned_show(struct gendisk *disk, char *page)
 {
 	if (blk_queue_is_zoned(disk->queue))
-		return sprintf(page, "host-managed\n");
+		return sysfs_emit(page, "host-managed\n");
-	return sprintf(page, "none\n");
+	return sysfs_emit(page, "none\n");
 }
 
 static ssize_t queue_nr_zones_show(struct gendisk *disk, char *page)
@@ -377,7 +377,7 @@ static ssize_t queue_poll_store(struct gendisk *disk, const char *page,
 
 static ssize_t queue_io_timeout_show(struct gendisk *disk, char *page)
 {
-	return sprintf(page, "%u\n", jiffies_to_msecs(disk->queue->rq_timeout));
+	return sysfs_emit(page, "%u\n", jiffies_to_msecs(disk->queue->rq_timeout));
 }
 
 static ssize_t queue_io_timeout_store(struct gendisk *disk, const char *page,
@@ -398,8 +398,8 @@ static ssize_t queue_io_timeout_store(struct gendisk *disk, const char *page,
 static ssize_t queue_wc_show(struct gendisk *disk, char *page)
 {
 	if (blk_queue_write_cache(disk->queue))
-		return sprintf(page, "write back\n");
+		return sysfs_emit(page, "write back\n");
-	return sprintf(page, "write through\n");
+	return sysfs_emit(page, "write through\n");
 }
 
 static ssize_t queue_wc_store(struct gendisk *disk, const char *page,
@@ -530,9 +530,9 @@ static ssize_t queue_wb_lat_show(struct gendisk *disk, char *page)
 		return -EINVAL;
 
 	if (wbt_disabled(disk->queue))
-		return sprintf(page, "0\n");
+		return sysfs_emit(page, "0\n");
 
-	return sprintf(page, "%llu\n",
+	return sysfs_emit(page, "%llu\n",
 		div_u64(wbt_get_min_lat(disk->queue), 1000));
 }
 

block/genhd.c

@@ -783,7 +783,7 @@ static ssize_t disk_badblocks_show(struct device *dev,
 	struct gendisk *disk = dev_to_disk(dev);
 
 	if (!disk->bb)
-		return sprintf(page, "\n");
+		return sysfs_emit(page, "\n");
 
 	return badblocks_show(disk->bb, page, 0);
 }
@@ -931,7 +931,7 @@ static ssize_t disk_range_show(struct device *dev,
 {
 	struct gendisk *disk = dev_to_disk(dev);
 
-	return sprintf(buf, "%d\n", disk->minors);
+	return sysfs_emit(buf, "%d\n", disk->minors);
 }
 
 static ssize_t disk_ext_range_show(struct device *dev,
@@ -939,7 +939,7 @@ static ssize_t disk_ext_range_show(struct device *dev,
 {
 	struct gendisk *disk = dev_to_disk(dev);
 
-	return sprintf(buf, "%d\n",
+	return sysfs_emit(buf, "%d\n",
 		(disk->flags & GENHD_FL_NO_PART) ? 1 : DISK_MAX_PARTS);
 }
 
@@ -948,7 +948,7 @@ static ssize_t disk_removable_show(struct device *dev,
 {
 	struct gendisk *disk = dev_to_disk(dev);
 
-	return sprintf(buf, "%d\n",
+	return sysfs_emit(buf, "%d\n",
 		       (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
 }
 
@@ -957,7 +957,7 @@ static ssize_t disk_hidden_show(struct device *dev,
 {
 	struct gendisk *disk = dev_to_disk(dev);
 
-	return sprintf(buf, "%d\n",
+	return sysfs_emit(buf, "%d\n",
 		       (disk->flags & GENHD_FL_HIDDEN ? 1 : 0));
 }
 
@@ -966,13 +966,13 @@ static ssize_t disk_ro_show(struct device *dev,
 {
 	struct gendisk *disk = dev_to_disk(dev);
 
-	return sprintf(buf, "%d\n", get_disk_ro(disk) ? 1 : 0);
+	return sysfs_emit(buf, "%d\n", get_disk_ro(disk) ? 1 : 0);
 }
 
 ssize_t part_size_show(struct device *dev,
 		       struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%llu\n", bdev_nr_sectors(dev_to_bdev(dev)));
+	return sysfs_emit(buf, "%llu\n", bdev_nr_sectors(dev_to_bdev(dev)));
 }
 
 ssize_t part_stat_show(struct device *dev,
@@ -989,7 +989,7 @@ ssize_t part_stat_show(struct device *dev,
 		part_stat_unlock();
 	}
 	part_stat_read_all(bdev, &stat);
-	return sprintf(buf,
+	return sysfs_emit(buf,
 		"%8lu %8lu %8llu %8u "
 		"%8lu %8lu %8llu %8u "
 		"%8u %8u %8u "
@@ -1031,14 +1031,14 @@ ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr,
 	else
 		part_in_flight_rw(bdev, inflight);
 
-	return sprintf(buf, "%8u %8u\n", inflight[0], inflight[1]);
+	return sysfs_emit(buf, "%8u %8u\n", inflight[0], inflight[1]);
 }
 
 static ssize_t disk_capability_show(struct device *dev,
 				    struct device_attribute *attr, char *buf)
 {
 	dev_warn_once(dev, "the capability attribute has been deprecated.\n");
-	return sprintf(buf, "0\n");
+	return sysfs_emit(buf, "0\n");
 }
 
 static ssize_t disk_alignment_offset_show(struct device *dev,
@@ -1047,7 +1047,7 @@ static ssize_t disk_alignment_offset_show(struct device *dev,
 {
 	struct gendisk *disk = dev_to_disk(dev);
 
-	return sprintf(buf, "%d\n", bdev_alignment_offset(disk->part0));
+	return sysfs_emit(buf, "%d\n", bdev_alignment_offset(disk->part0));
 }
 
 static ssize_t disk_discard_alignment_show(struct device *dev,
@@ -1056,7 +1056,7 @@ static ssize_t disk_discard_alignment_show(struct device *dev,
 {
 	struct gendisk *disk = dev_to_disk(dev);
 
-	return sprintf(buf, "%d\n", bdev_alignment_offset(disk->part0));
+	return sysfs_emit(buf, "%d\n", bdev_alignment_offset(disk->part0));
 }
 
 static ssize_t diskseq_show(struct device *dev,
@@ -1064,13 +1064,13 @@ static ssize_t diskseq_show(struct device *dev,
 {
 	struct gendisk *disk = dev_to_disk(dev);
 
-	return sprintf(buf, "%llu\n", disk->diskseq);
+	return sysfs_emit(buf, "%llu\n", disk->diskseq);
 }
 
 static ssize_t partscan_show(struct device *dev,
 		struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%u\n", disk_has_partscan(dev_to_disk(dev)));
+	return sysfs_emit(buf, "%u\n", disk_has_partscan(dev_to_disk(dev)));
 }
 
 static DEVICE_ATTR(range, 0444, disk_range_show, NULL);
@@ -1092,7 +1092,7 @@ static DEVICE_ATTR(partscan, 0444, partscan_show, NULL);
 ssize_t part_fail_show(struct device *dev,
 		       struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%d\n",
+	return sysfs_emit(buf, "%d\n",
 		       bdev_test_flag(dev_to_bdev(dev), BD_MAKE_IT_FAIL));
 }