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

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>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Link: https://lore.kernel.org/r/20250627035256.1120740-1-rk0006818@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 54c57103715f9b1af25f513d13d2dc8a98bde71e..385aaaa2531b8f025a9dd6e7ff949cba46ca9508 100644 (file)
--- 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)
@@ -1415,7 +1415,7 @@ 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);
        }
 
@@ -1488,7 +1488,7 @@ 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),
@@ -1518,7 +1518,7 @@ 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),
@@ -1543,8 +1543,8 @@ 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)));
@@ -1562,7 +1562,7 @@ 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));
@@ -2810,7 +2810,7 @@ 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 =