[PATCH] block: zram: replace scnprintf() with sysfs_emit() in *_show() functions

Rahul Kumar
2025-06-27T03:53:25Z

Replace scnprintf() with sysfs_emit() or sysfs_emit_at() in sysfs
*_show() functions in zram_drv.c to follow the kernel's guidelines
from Documentation/filesystems/sysfs.rst.

This improves consistency, safety, and makes the code easier to
maintain and update in the future.

Signed-off-by: Rahul Kumar <rk0006818@gmail.com>
---
drivers/block/zram/zram_drv.c | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index fda7d8624889..a1f2f45d4b99 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -373,7 +373,7 @@ static ssize_t initstate_show(struct device *dev,
val = init_done(zram);
up_read(&zram->init_lock);

- return scnprintf(buf, PAGE_SIZE, "%u\n", val);
+ return sysfs_emit(buf, "%u\n", val);
}

static ssize_t disksize_show(struct device *dev,
@@ -381,7 +381,7 @@ static ssize_t disksize_show(struct device *dev,
{
struct zram *zram = dev_to_zram(dev);

- return scnprintf(buf, PAGE_SIZE, "%llu\n", zram->disksize);
+ return sysfs_emit(buf, "%llu\n", zram->disksize);
}

static ssize_t mem_limit_store(struct device *dev,
@@ -532,7 +532,7 @@ static ssize_t writeback_limit_enable_show(struct device *dev,
spin_unlock(&zram->wb_limit_lock);
up_read(&zram->init_lock);

- return scnprintf(buf, PAGE_SIZE, "%d\n", val);
+ return sysfs_emit(buf, "%d\n", val);
}

static ssize_t writeback_limit_store(struct device *dev,
@@ -567,7 +567,7 @@ static ssize_t writeback_limit_show(struct device *dev,
spin_unlock(&zram->wb_limit_lock);
up_read(&zram->init_lock);

- return scnprintf(buf, PAGE_SIZE, "%llu\n", val);
+ return sysfs_emit(buf, "%llu\n", val);
}

static void reset_bdev(struct zram *zram)
@@ -1292,7 +1292,7 @@ static ssize_t recomp_algorithm_show(struct device *dev,
if (!zram->comp_algs[prio])
continue;

- sz += scnprintf(buf + sz, PAGE_SIZE - sz - 2, "#%d: ", prio);
+ sz += sysfs_emit_at(buf, sz, "#%d: ", prio);
sz += __comp_algorithm_show(zram, prio, buf + sz);
}

@@ -1365,7 +1365,7 @@ static ssize_t io_stat_show(struct device *dev,
ssize_t ret;

down_read(&zram->init_lock);
- ret = scnprintf(buf, PAGE_SIZE,
+ ret = sysfs_emit(buf,
"%8llu %8llu 0 %8llu\n",
(u64)atomic64_read(&zram->stats.failed_reads),
(u64)atomic64_read(&zram->stats.failed_writes),
@@ -1395,7 +1395,7 @@ static ssize_t mm_stat_show(struct device *dev,
orig_size = atomic64_read(&zram->stats.pages_stored);
max_used = atomic_long_read(&zram->stats.max_used_pages);

- ret = scnprintf(buf, PAGE_SIZE,
+ ret = sysfs_emit(buf,
"%8llu %8llu %8llu %8lu %8ld %8llu %8lu %8llu %8llu\n",
orig_size << PAGE_SHIFT,
(u64)atomic64_read(&zram->stats.compr_data_size),
@@ -1420,8 +1420,8 @@ static ssize_t bd_stat_show(struct device *dev,
ssize_t ret;

down_read(&zram->init_lock);
- ret = scnprintf(buf, PAGE_SIZE,
- "%8llu %8llu %8llu\n",
+ ret = sysfs_emit(buf,
+ "%8llu %8llu %8llu\n",
FOUR_K((u64)atomic64_read(&zram->stats.bd_count)),
FOUR_K((u64)atomic64_read(&zram->stats.bd_reads)),
FOUR_K((u64)atomic64_read(&zram->stats.bd_writes)));
@@ -1439,7 +1439,7 @@ static ssize_t debug_stat_show(struct device *dev,
ssize_t ret;

down_read(&zram->init_lock);
- ret = scnprintf(buf, PAGE_SIZE,
+ ret = sysfs_emit(buf,
"version: %d\n0 %8llu\n",
version,
(u64)atomic64_read(&zram->stats.miss_free));
@@ -2682,7 +2682,7 @@ static ssize_t hot_add_show(const struct class *class,

if (ret < 0)
return ret;
- return scnprintf(buf, PAGE_SIZE, "%d\n", ret);
+ return sysfs_emit(buf, "%d\n", ret);
}
/* This attribute must be set to 0400, so CLASS_ATTR_RO() can not be used */
static struct class_attribute class_attr_hot_add =
--
2.43.0